diff --git a/ext/mbedtls-asn1/include/common.h b/ext/mbedtls-asn1/include/common.h
new file mode 100644
index 0000000..a2c8a1e
--- /dev/null
+++ b/ext/mbedtls-asn1/include/common.h
@@ -0,0 +1,56 @@
+/**
+ * \file common.h
+ *
+ * \brief Utility macros for internal use in the library
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#ifndef MBEDTLS_LIBRARY_COMMON_H
+#define MBEDTLS_LIBRARY_COMMON_H
+
+#include "mbedtls/build_info.h"
+
+/** Helper to define a function as static except when building invasive tests.
+ *
+ * If a function is only used inside its own source file and should be
+ * declared `static` to allow the compiler to optimize for code size,
+ * but that function has unit tests, define it with
+ * ```
+ * MBEDTLS_STATIC_TESTABLE int mbedtls_foo(...) { ... }
+ * ```
+ * and declare it in a header in the `library/` directory with
+ * ```
+ * #if defined(MBEDTLS_TEST_HOOKS)
+ * int mbedtls_foo(...);
+ * #endif
+ * ```
+ */
+#if defined(MBEDTLS_TEST_HOOKS)
+#define MBEDTLS_STATIC_TESTABLE
+#else
+#define MBEDTLS_STATIC_TESTABLE static
+#endif
+
+/** Allow library to access its structs' private members.
+ *
+ * Although structs defined in header files are publicly available,
+ * their members are private and should not be accessed by the user.
+ */
+#define MBEDTLS_ALLOW_PRIVATE_ACCESS
+
+#endif /* MBEDTLS_LIBRARY_COMMON_H */
diff --git a/ext/mbedtls-asn1/include/mbedtls/asn1.h b/ext/mbedtls-asn1/include/mbedtls/asn1.h
index 96c1c9a..4668581 100644
--- a/ext/mbedtls-asn1/include/mbedtls/asn1.h
+++ b/ext/mbedtls-asn1/include/mbedtls/asn1.h
@@ -4,7 +4,7 @@
  * \brief Generic ASN.1 parsing
  */
 /*
- *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -18,22 +18,17 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 #ifndef MBEDTLS_ASN1_H
 #define MBEDTLS_ASN1_H
+#include "mbedtls/private_access.h"
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
 #include <stddef.h>
 
 #if defined(MBEDTLS_BIGNUM_C)
-#include "bignum.h"
+#include "mbedtls/bignum.h"
 #endif
 
 /**
@@ -52,7 +47,7 @@
 #define MBEDTLS_ERR_ASN1_UNEXPECTED_TAG                   -0x0062  /**< ASN1 tag was of an unexpected value. */
 #define MBEDTLS_ERR_ASN1_INVALID_LENGTH                   -0x0064  /**< Error when trying to determine the length or invalid length. */
 #define MBEDTLS_ERR_ASN1_LENGTH_MISMATCH                  -0x0066  /**< Actual length differs from expected length. */
-#define MBEDTLS_ERR_ASN1_INVALID_DATA                     -0x0068  /**< Data is invalid. (not used) */
+#define MBEDTLS_ERR_ASN1_INVALID_DATA                     -0x0068  /**< Data is invalid. */
 #define MBEDTLS_ERR_ASN1_ALLOC_FAILED                     -0x006A  /**< Memory allocation failed */
 #define MBEDTLS_ERR_ASN1_BUF_TOO_SMALL                    -0x006C  /**< Buffer too small when writing ASN.1 data structure. */
 
@@ -75,6 +70,7 @@
 #define MBEDTLS_ASN1_OCTET_STRING            0x04
 #define MBEDTLS_ASN1_NULL                    0x05
 #define MBEDTLS_ASN1_OID                     0x06
+#define MBEDTLS_ASN1_ENUMERATED              0x0A
 #define MBEDTLS_ASN1_UTF8_STRING             0x0C
 #define MBEDTLS_ASN1_SEQUENCE                0x10
 #define MBEDTLS_ASN1_SET                     0x11
@@ -89,6 +85,18 @@
 #define MBEDTLS_ASN1_CONSTRUCTED             0x20
 #define MBEDTLS_ASN1_CONTEXT_SPECIFIC        0x80
 
+/* Slightly smaller way to check if tag is a string tag
+ * compared to canonical implementation. */
+#define MBEDTLS_ASN1_IS_STRING_TAG( tag )                                     \
+    ( ( tag ) < 32u && (                                                      \
+        ( ( 1u << ( tag ) ) & ( ( 1u << MBEDTLS_ASN1_BMP_STRING )       |     \
+                                ( 1u << MBEDTLS_ASN1_UTF8_STRING )      |     \
+                                ( 1u << MBEDTLS_ASN1_T61_STRING )       |     \
+                                ( 1u << MBEDTLS_ASN1_IA5_STRING )       |     \
+                                ( 1u << MBEDTLS_ASN1_UNIVERSAL_STRING ) |     \
+                                ( 1u << MBEDTLS_ASN1_PRINTABLE_STRING ) |     \
+                                ( 1u << MBEDTLS_ASN1_BIT_STRING ) ) ) != 0 ) )
+
 /*
  * Bit masks for each of the components of an ASN.1 tag as specified in
  * ITU X.690 (08/2015), section 8.1 "General rules for encoding",
@@ -119,6 +127,10 @@
         ( ( MBEDTLS_OID_SIZE(oid_str) != (oid_buf)->len ) ||                \
           memcmp( (oid_str), (oid_buf)->p, (oid_buf)->len) != 0 )
 
+#define MBEDTLS_OID_CMP_RAW(oid_str, oid_buf, oid_buf_len)              \
+        ( ( MBEDTLS_OID_SIZE(oid_str) != (oid_buf_len) ) ||             \
+          memcmp( (oid_str), (oid_buf), (oid_buf_len) ) != 0 )
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -133,9 +145,9 @@
  */
 typedef struct mbedtls_asn1_buf
 {
-    int tag;                /**< ASN1 type, e.g. MBEDTLS_ASN1_UTF8_STRING. */
-    size_t len;             /**< ASN1 length, in octets. */
-    unsigned char *p;       /**< ASN1 data, e.g. in ASCII. */
+    int MBEDTLS_PRIVATE(tag);                /**< ASN1 type, e.g. MBEDTLS_ASN1_UTF8_STRING. */
+    size_t MBEDTLS_PRIVATE(len);             /**< ASN1 length, in octets. */
+    unsigned char *MBEDTLS_PRIVATE(p);       /**< ASN1 data, e.g. in ASCII. */
 }
 mbedtls_asn1_buf;
 
@@ -144,9 +156,9 @@
  */
 typedef struct mbedtls_asn1_bitstring
 {
-    size_t len;                 /**< ASN1 length, in octets. */
-    unsigned char unused_bits;  /**< Number of unused bits at the end of the string */
-    unsigned char *p;           /**< Raw ASN1 data for the bit string */
+    size_t MBEDTLS_PRIVATE(len);                 /**< ASN1 length, in octets. */
+    unsigned char MBEDTLS_PRIVATE(unused_bits);  /**< Number of unused bits at the end of the string */
+    unsigned char *MBEDTLS_PRIVATE(p);           /**< Raw ASN1 data for the bit string */
 }
 mbedtls_asn1_bitstring;
 
@@ -155,8 +167,8 @@
  */
 typedef struct mbedtls_asn1_sequence
 {
-    mbedtls_asn1_buf buf;                   /**< Buffer containing the given ASN.1 item. */
-    struct mbedtls_asn1_sequence *next;    /**< The next entry in the sequence. */
+    mbedtls_asn1_buf MBEDTLS_PRIVATE(buf);                   /**< Buffer containing the given ASN.1 item. */
+    struct mbedtls_asn1_sequence *MBEDTLS_PRIVATE(next);    /**< The next entry in the sequence. */
 }
 mbedtls_asn1_sequence;
 
@@ -165,10 +177,10 @@
  */
 typedef struct mbedtls_asn1_named_data
 {
-    mbedtls_asn1_buf oid;                   /**< The object identifier. */
-    mbedtls_asn1_buf val;                   /**< The named value. */
-    struct mbedtls_asn1_named_data *next;  /**< The next entry in the sequence. */
-    unsigned char next_merged;      /**< Merge next item into the current one? */
+    mbedtls_asn1_buf MBEDTLS_PRIVATE(oid);                   /**< The object identifier. */
+    mbedtls_asn1_buf MBEDTLS_PRIVATE(val);                   /**< The named value. */
+    struct mbedtls_asn1_named_data *MBEDTLS_PRIVATE(next);  /**< The next entry in the sequence. */
+    unsigned char MBEDTLS_PRIVATE(next_merged);      /**< Merge next item into the current one? */
 }
 mbedtls_asn1_named_data;
 
@@ -176,119 +188,342 @@
  * \brief       Get the length of an ASN.1 element.
  *              Updates the pointer to immediately behind the length.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param len   The variable that will receive the value
+ * \param p     On entry, \c *p points to the first byte of the length,
+ *              i.e. immediately after the tag.
+ *              On successful completion, \c *p points to the first byte
+ *              after the length, i.e. the first byte of the content.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param len   On successful completion, \c *len contains the length
+ *              read from the ASN.1 input.
  *
- * \return      0 if successful, MBEDTLS_ERR_ASN1_OUT_OF_DATA on reaching
- *              end of data, MBEDTLS_ERR_ASN1_INVALID_LENGTH if length is
- *              unparseable.
+ * \return      0 if successful.
+ * \return      #MBEDTLS_ERR_ASN1_OUT_OF_DATA if the ASN.1 element
+ *              would end beyond \p end.
+ * \return      #MBEDTLS_ERR_ASN1_INVALID_LENGTH if the length is unparseable.
  */
 int mbedtls_asn1_get_len( unsigned char **p,
-                  const unsigned char *end,
-                  size_t *len );
+                          const unsigned char *end,
+                          size_t *len );
 
 /**
- * \brief       Get the tag and length of the tag. Check for the requested tag.
+ * \brief       Get the tag and length of the element.
+ *              Check for the requested tag.
  *              Updates the pointer to immediately behind the tag and length.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param len   The variable that will receive the length
- * \param tag   The expected tag
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              after the length, i.e. the first byte of the content.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param len   On successful completion, \c *len contains the length
+ *              read from the ASN.1 input.
+ * \param tag   The expected tag.
  *
- * \return      0 if successful, MBEDTLS_ERR_ASN1_UNEXPECTED_TAG if tag did
- *              not match requested tag, or another specific ASN.1 error code.
+ * \return      0 if successful.
+ * \return      #MBEDTLS_ERR_ASN1_UNEXPECTED_TAG if the data does not start
+ *              with the requested tag.
+ * \return      #MBEDTLS_ERR_ASN1_OUT_OF_DATA if the ASN.1 element
+ *              would end beyond \p end.
+ * \return      #MBEDTLS_ERR_ASN1_INVALID_LENGTH if the length is unparseable.
  */
 int mbedtls_asn1_get_tag( unsigned char **p,
-                  const unsigned char *end,
-                  size_t *len, int tag );
+                          const unsigned char *end,
+                          size_t *len, int tag );
 
 /**
  * \brief       Retrieve a boolean ASN.1 tag and its value.
  *              Updates the pointer to immediately behind the full tag.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param val   The variable that will receive the value
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              beyond the ASN.1 element.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param val   On success, the parsed value (\c 0 or \c 1).
  *
- * \return      0 if successful or a specific ASN.1 error code.
+ * \return      0 if successful.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 BOOLEAN.
  */
 int mbedtls_asn1_get_bool( unsigned char **p,
-                   const unsigned char *end,
-                   int *val );
+                           const unsigned char *end,
+                           int *val );
 
 /**
  * \brief       Retrieve an integer ASN.1 tag and its value.
  *              Updates the pointer to immediately behind the full tag.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param val   The variable that will receive the value
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              beyond the ASN.1 element.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param val   On success, the parsed value.
  *
- * \return      0 if successful or a specific ASN.1 error code.
+ * \return      0 if successful.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 INTEGER.
+ * \return      #MBEDTLS_ERR_ASN1_INVALID_LENGTH if the parsed value does
+ *              not fit in an \c int.
  */
 int mbedtls_asn1_get_int( unsigned char **p,
-                  const unsigned char *end,
-                  int *val );
+                          const unsigned char *end,
+                          int *val );
+
+/**
+ * \brief       Retrieve an enumerated ASN.1 tag and its value.
+ *              Updates the pointer to immediately behind the full tag.
+ *
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              beyond the ASN.1 element.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param val   On success, the parsed value.
+ *
+ * \return      0 if successful.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 ENUMERATED.
+ * \return      #MBEDTLS_ERR_ASN1_INVALID_LENGTH if the parsed value does
+ *              not fit in an \c int.
+ */
+int mbedtls_asn1_get_enum( unsigned char **p,
+                           const unsigned char *end,
+                           int *val );
 
 /**
  * \brief       Retrieve a bitstring ASN.1 tag and its value.
  *              Updates the pointer to immediately behind the full tag.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param bs    The variable that will receive the value
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p is equal to \p end.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param bs    On success, ::mbedtls_asn1_bitstring information about
+ *              the parsed value.
  *
- * \return      0 if successful or a specific ASN.1 error code.
+ * \return      0 if successful.
+ * \return      #MBEDTLS_ERR_ASN1_LENGTH_MISMATCH if the input contains
+ *              extra data after a valid BIT STRING.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 BIT STRING.
  */
 int mbedtls_asn1_get_bitstring( unsigned char **p, const unsigned char *end,
-                        mbedtls_asn1_bitstring *bs);
+                                mbedtls_asn1_bitstring *bs );
 
 /**
  * \brief       Retrieve a bitstring ASN.1 tag without unused bits and its
  *              value.
  *              Updates the pointer to the beginning of the bit/octet string.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param len   Length of the actual bit/octect string in bytes
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              of the content of the BIT STRING.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param len   On success, \c *len is the length of the content in bytes.
  *
- * \return      0 if successful or a specific ASN.1 error code.
+ * \return      0 if successful.
+ * \return      #MBEDTLS_ERR_ASN1_INVALID_DATA if the input starts with
+ *              a valid BIT STRING with a nonzero number of unused bits.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 BIT STRING.
  */
-int mbedtls_asn1_get_bitstring_null( unsigned char **p, const unsigned char *end,
-                             size_t *len );
+int mbedtls_asn1_get_bitstring_null( unsigned char **p,
+                                     const unsigned char *end,
+                                     size_t *len );
 
 /**
- * \brief       Parses and splits an ASN.1 "SEQUENCE OF <tag>"
- *              Updated the pointer to immediately behind the full sequence tag.
+ * \brief       Parses and splits an ASN.1 "SEQUENCE OF <tag>".
+ *              Updates the pointer to immediately behind the full sequence tag.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param cur   First variable in the chain to fill
- * \param tag   Type of sequence
+ * This function allocates memory for the sequence elements. You can free
+ * the allocated memory with mbedtls_asn1_sequence_free().
  *
- * \return      0 if successful or a specific ASN.1 error code.
+ * \note        On error, this function may return a partial list in \p cur.
+ *              You must set `cur->next = NULL` before calling this function!
+ *              Otherwise it is impossible to distinguish a previously non-null
+ *              pointer from a pointer to an object allocated by this function.
+ *
+ * \note        If the sequence is empty, this function does not modify
+ *              \c *cur. If the sequence is valid and non-empty, this
+ *              function sets `cur->buf.tag` to \p tag. This allows
+ *              callers to distinguish between an empty sequence and
+ *              a one-element sequence.
+ *
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p is equal to \p end.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param cur   A ::mbedtls_asn1_sequence which this function fills.
+ *              When this function returns, \c *cur is the head of a linked
+ *              list. Each node in this list is allocated with
+ *              mbedtls_calloc() apart from \p cur itself, and should
+ *              therefore be freed with mbedtls_free().
+ *              The list describes the content of the sequence.
+ *              The head of the list (i.e. \c *cur itself) describes the
+ *              first element, `*cur->next` describes the second element, etc.
+ *              For each element, `buf.tag == tag`, `buf.len` is the length
+ *              of the content of the content of the element, and `buf.p`
+ *              points to the first byte of the content (i.e. immediately
+ *              past the length of the element).
+ *              Note that list elements may be allocated even on error.
+ * \param tag   Each element of the sequence must have this tag.
+ *
+ * \return      0 if successful.
+ * \return      #MBEDTLS_ERR_ASN1_LENGTH_MISMATCH if the input contains
+ *              extra data after a valid SEQUENCE OF \p tag.
+ * \return      #MBEDTLS_ERR_ASN1_UNEXPECTED_TAG if the input starts with
+ *              an ASN.1 SEQUENCE in which an element has a tag that
+ *              is different from \p tag.
+ * \return      #MBEDTLS_ERR_ASN1_ALLOC_FAILED if a memory allocation failed.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 SEQUENCE.
  */
 int mbedtls_asn1_get_sequence_of( unsigned char **p,
-                          const unsigned char *end,
-                          mbedtls_asn1_sequence *cur,
-                          int tag);
+                                  const unsigned char *end,
+                                  mbedtls_asn1_sequence *cur,
+                                  int tag );
+/**
+ * \brief          Free a heap-allocated linked list presentation of
+ *                 an ASN.1 sequence, including the first element.
+ *
+ * There are two common ways to manage the memory used for the representation
+ * of a parsed ASN.1 sequence:
+ * - Allocate a head node `mbedtls_asn1_sequence *head` with mbedtls_calloc().
+ *   Pass this node as the `cur` argument to mbedtls_asn1_get_sequence_of().
+ *   When you have finished processing the sequence,
+ *   call mbedtls_asn1_sequence_free() on `head`.
+ * - Allocate a head node `mbedtls_asn1_sequence *head` in any manner,
+ *   for example on the stack. Make sure that `head->next == NULL`.
+ *   Pass `head` as the `cur` argument to mbedtls_asn1_get_sequence_of().
+ *   When you have finished processing the sequence,
+ *   call mbedtls_asn1_sequence_free() on `head->cur`,
+ *   then free `head` itself in the appropriate manner.
+ *
+ * \param seq      The address of the first sequence component. This may
+ *                 be \c NULL, in which case this functions returns
+ *                 immediately.
+ */
+void mbedtls_asn1_sequence_free( mbedtls_asn1_sequence *seq );
+
+/**
+ * \brief                Traverse an ASN.1 SEQUENCE container and
+ *                       call a callback for each entry.
+ *
+ * This function checks that the input is a SEQUENCE of elements that
+ * each have a "must" tag, and calls a callback function on the elements
+ * that have a "may" tag.
+ *
+ * For example, to validate that the input is a SEQUENCE of `tag1` and call
+ * `cb` on each element, use
+ * ```
+ * mbedtls_asn1_traverse_sequence_of(&p, end, 0xff, tag1, 0, 0, cb, ctx);
+ * ```
+ *
+ * To validate that the input is a SEQUENCE of ANY and call `cb` on
+ * each element, use
+ * ```
+ * mbedtls_asn1_traverse_sequence_of(&p, end, 0, 0, 0, 0, cb, ctx);
+ * ```
+ *
+ * To validate that the input is a SEQUENCE of CHOICE {NULL, OCTET STRING}
+ * and call `cb` on each element that is an OCTET STRING, use
+ * ```
+ * mbedtls_asn1_traverse_sequence_of(&p, end, 0xfe, 0x04, 0xff, 0x04, cb, ctx);
+ * ```
+ *
+ * The callback is called on the elements with a "may" tag from left to
+ * right. If the input is not a valid SEQUENCE of elements with a "must" tag,
+ * the callback is called on the elements up to the leftmost point where
+ * the input is invalid.
+ *
+ * \warning              This function is still experimental and may change
+ *                       at any time.
+ *
+ * \param p              The address of the pointer to the beginning of
+ *                       the ASN.1 SEQUENCE header. This is updated to
+ *                       point to the end of the ASN.1 SEQUENCE container
+ *                       on a successful invocation.
+ * \param end            The end of the ASN.1 SEQUENCE container.
+ * \param tag_must_mask  A mask to be applied to the ASN.1 tags found within
+ *                       the SEQUENCE before comparing to \p tag_must_value.
+ * \param tag_must_val   The required value of each ASN.1 tag found in the
+ *                       SEQUENCE, after masking with \p tag_must_mask.
+ *                       Mismatching tags lead to an error.
+ *                       For example, a value of \c 0 for both \p tag_must_mask
+ *                       and \p tag_must_val means that every tag is allowed,
+ *                       while a value of \c 0xFF for \p tag_must_mask means
+ *                       that \p tag_must_val is the only allowed tag.
+ * \param tag_may_mask   A mask to be applied to the ASN.1 tags found within
+ *                       the SEQUENCE before comparing to \p tag_may_value.
+ * \param tag_may_val    The desired value of each ASN.1 tag found in the
+ *                       SEQUENCE, after masking with \p tag_may_mask.
+ *                       Mismatching tags will be silently ignored.
+ *                       For example, a value of \c 0 for \p tag_may_mask and
+ *                       \p tag_may_val means that any tag will be considered,
+ *                       while a value of \c 0xFF for \p tag_may_mask means
+ *                       that all tags with value different from \p tag_may_val
+ *                       will be ignored.
+ * \param cb             The callback to trigger for each component
+ *                       in the ASN.1 SEQUENCE that matches \p tag_may_val.
+ *                       The callback function is called with the following
+ *                       parameters:
+ *                       - \p ctx.
+ *                       - The tag of the current element.
+ *                       - A pointer to the start of the current element's
+ *                         content inside the input.
+ *                       - The length of the content of the current element.
+ *                       If the callback returns a non-zero value,
+ *                       the function stops immediately,
+ *                       forwarding the callback's return value.
+ * \param ctx            The context to be passed to the callback \p cb.
+ *
+ * \return               \c 0 if successful the entire ASN.1 SEQUENCE
+ *                       was traversed without parsing or callback errors.
+ * \return               #MBEDTLS_ERR_ASN1_LENGTH_MISMATCH if the input
+ *                       contains extra data after a valid SEQUENCE
+ *                       of elements with an accepted tag.
+ * \return               #MBEDTLS_ERR_ASN1_UNEXPECTED_TAG if the input starts
+ *                       with an ASN.1 SEQUENCE in which an element has a tag
+ *                       that is not accepted.
+ * \return               An ASN.1 error code if the input does not start with
+ *                       a valid ASN.1 SEQUENCE.
+ * \return               A non-zero error code forwarded from the callback
+ *                       \p cb in case the latter returns a non-zero value.
+ */
+int mbedtls_asn1_traverse_sequence_of(
+    unsigned char **p,
+    const unsigned char *end,
+    unsigned char tag_must_mask, unsigned char tag_must_val,
+    unsigned char tag_may_mask, unsigned char tag_may_val,
+    int (*cb)( void *ctx, int tag,
+               unsigned char* start, size_t len ),
+    void *ctx );
 
 #if defined(MBEDTLS_BIGNUM_C)
 /**
- * \brief       Retrieve a MPI value from an integer ASN.1 tag.
+ * \brief       Retrieve an integer ASN.1 tag and its value.
  *              Updates the pointer to immediately behind the full tag.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param X     The MPI that will receive the value
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              beyond the ASN.1 element.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param X     On success, the parsed value.
  *
- * \return      0 if successful or a specific ASN.1 or MPI error code.
+ * \return      0 if successful.
+ * \return      An ASN.1 error code if the input does not start with
+ *              a valid ASN.1 INTEGER.
+ * \return      #MBEDTLS_ERR_ASN1_INVALID_LENGTH if the parsed value does
+ *              not fit in an \c int.
+ * \return      An MPI error code if the parsed value is too large.
  */
 int mbedtls_asn1_get_mpi( unsigned char **p,
-                  const unsigned char *end,
-                  mbedtls_mpi *X );
+                          const unsigned char *end,
+                          mbedtls_mpi *X );
 #endif /* MBEDTLS_BIGNUM_C */
 
 /**
@@ -296,10 +531,14 @@
  *              Updates the pointer to immediately behind the full
  *              AlgorithmIdentifier.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param alg   The buffer to receive the OID
- * \param params The buffer to receive the params (if any)
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              beyond the AlgorithmIdentifier element.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param alg   The buffer to receive the OID.
+ * \param params The buffer to receive the parameters.
+ *              This is zeroized if there are no parameters.
  *
  * \return      0 if successful or a specific ASN.1 or MPI error code.
  */
@@ -313,9 +552,12 @@
  *              Updates the pointer to immediately behind the full
  *              AlgorithmIdentifier.
  *
- * \param p     The position in the ASN.1 data
- * \param end   End of data
- * \param alg   The buffer to receive the OID
+ * \param p     On entry, \c *p points to the start of the ASN.1 element.
+ *              On successful completion, \c *p points to the first byte
+ *              beyond the AlgorithmIdentifier element.
+ *              On error, the value of \c *p is undefined.
+ * \param end   End of data.
+ * \param alg   The buffer to receive the OID.
  *
  * \return      0 if successful or a specific ASN.1 or MPI error code.
  */
@@ -333,21 +575,25 @@
  *
  * \return      NULL if not found, or a pointer to the existing entry.
  */
-mbedtls_asn1_named_data *mbedtls_asn1_find_named_data( mbedtls_asn1_named_data *list,
+const mbedtls_asn1_named_data *mbedtls_asn1_find_named_data( const mbedtls_asn1_named_data *list,
                                        const char *oid, size_t len );
 
 /**
  * \brief       Free a mbedtls_asn1_named_data entry
  *
- * \param entry The named data entry to free
+ * \param entry The named data entry to free.
+ *              This function calls mbedtls_free() on
+ *              `entry->oid.p` and `entry->val.p`.
  */
 void mbedtls_asn1_free_named_data( mbedtls_asn1_named_data *entry );
 
 /**
- * \brief       Free all entries in a mbedtls_asn1_named_data list
- *              Head will be set to NULL
+ * \brief       Free all entries in a mbedtls_asn1_named_data list.
  *
- * \param head  Pointer to the head of the list of named data entries to free
+ * \param head  Pointer to the head of the list of named data entries to free.
+ *              This function calls mbedtls_asn1_free_named_data() and
+ *              mbedtls_free() on each list element and
+ *              sets \c *head to \c NULL.
  */
 void mbedtls_asn1_free_named_data_list( mbedtls_asn1_named_data **head );
 
diff --git a/ext/mbedtls-asn1/include/mbedtls/bignum.h b/ext/mbedtls-asn1/include/mbedtls/bignum.h
index 40cfab4..5187d86 100644
--- a/ext/mbedtls-asn1/include/mbedtls/bignum.h
+++ b/ext/mbedtls-asn1/include/mbedtls/bignum.h
@@ -4,7 +4,7 @@
  * \brief Multi-precision integer library
  */
 /*
- *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -18,17 +18,12 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 #ifndef MBEDTLS_BIGNUM_H
 #define MBEDTLS_BIGNUM_H
+#include "mbedtls/private_access.h"
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
 #include <stddef.h>
 #include <stdint.h>
@@ -46,7 +41,12 @@
 #define MBEDTLS_ERR_MPI_NOT_ACCEPTABLE                    -0x000E  /**< The input arguments are not acceptable. */
 #define MBEDTLS_ERR_MPI_ALLOC_FAILED                      -0x0010  /**< Memory allocation failed. */
 
-#define MBEDTLS_MPI_CHK(f) do { if( ( ret = f ) != 0 ) goto cleanup; } while( 0 )
+#define MBEDTLS_MPI_CHK(f)       \
+    do                           \
+    {                            \
+        if( ( ret = (f) ) != 0 ) \
+            goto cleanup;        \
+    } while( 0 )
 
 /*
  * Maximum size MPIs are allowed to grow to in number of limbs.
@@ -58,12 +58,12 @@
  * Maximum window size used for modular exponentiation. Default: 6
  * Minimum value: 1. Maximum value: 6.
  *
- * Result is an array of ( 2 << MBEDTLS_MPI_WINDOW_SIZE ) MPIs used
+ * Result is an array of ( 2 ** MBEDTLS_MPI_WINDOW_SIZE ) MPIs used
  * for the sliding window calculation. (So 64 by default)
  *
  * Reduction in size, reduces speed.
  */
-#define MBEDTLS_MPI_WINDOW_SIZE                           6        /**< Maximum windows size used. */
+#define MBEDTLS_MPI_WINDOW_SIZE                           6        /**< Maximum window size used. */
 #endif /* !MBEDTLS_MPI_WINDOW_SIZE */
 
 #if !defined(MBEDTLS_MPI_MAX_SIZE)
@@ -124,7 +124,8 @@
         defined(__ppc64__) || defined(__powerpc64__)  || \
         defined(__ia64__)  || defined(__alpha__)      || \
         ( defined(__sparc__) && defined(__arch64__) ) || \
-        defined(__s390x__) || defined(__mips64) )
+        defined(__s390x__) || defined(__mips64)       || \
+        defined(__aarch64__) )
         #if !defined(MBEDTLS_HAVE_INT64)
             #define MBEDTLS_HAVE_INT64
         #endif /* MBEDTLS_HAVE_INT64 */
@@ -179,103 +180,122 @@
  */
 typedef struct mbedtls_mpi
 {
-    int s;              /*!<  integer sign      */
-    size_t n;           /*!<  total # of limbs  */
-    mbedtls_mpi_uint *p;          /*!<  pointer to limbs  */
+    int MBEDTLS_PRIVATE(s);              /*!<  Sign: -1 if the mpi is negative, 1 otherwise */
+    size_t MBEDTLS_PRIVATE(n);           /*!<  total # of limbs  */
+    mbedtls_mpi_uint *MBEDTLS_PRIVATE(p);          /*!<  pointer to limbs  */
 }
 mbedtls_mpi;
 
 /**
- * \brief           Initialize one MPI (make internal references valid)
- *                  This just makes it ready to be set or freed,
+ * \brief           Initialize an MPI context.
+ *
+ *                  This makes the MPI ready to be set or freed,
  *                  but does not define a value for the MPI.
  *
- * \param X         One MPI to initialize.
+ * \param X         The MPI context to initialize. This must not be \c NULL.
  */
 void mbedtls_mpi_init( mbedtls_mpi *X );
 
 /**
- * \brief          Unallocate one MPI
+ * \brief          This function frees the components of an MPI context.
  *
- * \param X        One MPI to unallocate.
+ * \param X        The MPI context to be cleared. This may be \c NULL,
+ *                 in which case this function is a no-op. If it is
+ *                 not \c NULL, it must point to an initialized MPI.
  */
 void mbedtls_mpi_free( mbedtls_mpi *X );
 
 /**
- * \brief          Enlarge to the specified number of limbs
+ * \brief          Enlarge an MPI to the specified number of limbs.
  *
- *                 This function does nothing if the MPI is already large enough.
+ * \note           This function does nothing if the MPI is
+ *                 already large enough.
  *
- * \param X        MPI to grow
- * \param nblimbs  The target number of limbs
+ * \param X        The MPI to grow. It must be initialized.
+ * \param nblimbs  The target number of limbs.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_grow( mbedtls_mpi *X, size_t nblimbs );
 
 /**
- * \brief          Resize down, keeping at least the specified number of limbs
+ * \brief          This function resizes an MPI downwards, keeping at least the
+ *                 specified number of limbs.
  *
  *                 If \c X is smaller than \c nblimbs, it is resized up
  *                 instead.
  *
- * \param X        MPI to shrink
- * \param nblimbs  The minimum number of limbs to keep
+ * \param X        The MPI to shrink. This must point to an initialized MPI.
+ * \param nblimbs  The minimum number of limbs to keep.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
  *                 (this can only happen when resizing up).
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_shrink( mbedtls_mpi *X, size_t nblimbs );
 
 /**
- * \brief          Copy the contents of Y into X
+ * \brief          Make a copy of an MPI.
  *
- * \param X        Destination MPI. It is enlarged if necessary.
- * \param Y        Source MPI.
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param Y        The source MPI. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \note           The limb-buffer in the destination MPI is enlarged
+ *                 if necessary to hold the value in the source MPI.
+ *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_copy( mbedtls_mpi *X, const mbedtls_mpi *Y );
 
 /**
- * \brief          Swap the contents of X and Y
+ * \brief          Swap the contents of two MPIs.
  *
- * \param X        First MPI value
- * \param Y        Second MPI value
+ * \param X        The first MPI. It must be initialized.
+ * \param Y        The second MPI. It must be initialized.
  */
 void mbedtls_mpi_swap( mbedtls_mpi *X, mbedtls_mpi *Y );
 
 /**
- * \brief          Safe conditional assignement X = Y if assign is 1
+ * \brief          Perform a safe conditional copy of MPI which doesn't
+ *                 reveal whether the condition was true or not.
  *
- * \param X        MPI to conditionally assign to
- * \param Y        Value to be assigned
- * \param assign   1: perform the assignment, 0: keep X's original value
- *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
+ * \param X        The MPI to conditionally assign to. This must point
+ *                 to an initialized MPI.
+ * \param Y        The MPI to be assigned from. This must point to an
+ *                 initialized MPI.
+ * \param assign   The condition deciding whether to perform the
+ *                 assignment or not. Possible values:
+ *                 * \c 1: Perform the assignment `X = Y`.
+ *                 * \c 0: Keep the original value of \p X.
  *
  * \note           This function is equivalent to
- *                      if( assign ) mbedtls_mpi_copy( X, Y );
+ *                      `if( assign ) mbedtls_mpi_copy( X, Y );`
  *                 except that it avoids leaking any information about whether
  *                 the assignment was done or not (the above code may leak
  *                 information through branch prediction and/or memory access
  *                 patterns analysis).
+ *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_safe_cond_assign( mbedtls_mpi *X, const mbedtls_mpi *Y, unsigned char assign );
 
 /**
- * \brief          Safe conditional swap X <-> Y if swap is 1
+ * \brief          Perform a safe conditional swap which doesn't
+ *                 reveal whether the condition was true or not.
  *
- * \param X        First mbedtls_mpi value
- * \param Y        Second mbedtls_mpi value
- * \param assign   1: perform the swap, 0: keep X and Y's original values
- *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
+ * \param X        The first MPI. This must be initialized.
+ * \param Y        The second MPI. This must be initialized.
+ * \param assign   The condition deciding whether to perform
+ *                 the swap or not. Possible values:
+ *                 * \c 1: Swap the values of \p X and \p Y.
+ *                 * \c 0: Keep the original values of \p X and \p Y.
  *
  * \note           This function is equivalent to
  *                      if( assign ) mbedtls_mpi_swap( X, Y );
@@ -283,415 +303,564 @@
  *                 the assignment was done or not (the above code may leak
  *                 information through branch prediction and/or memory access
  *                 patterns analysis).
+ *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on other kinds of failure.
+ *
  */
 int mbedtls_mpi_safe_cond_swap( mbedtls_mpi *X, mbedtls_mpi *Y, unsigned char assign );
 
 /**
- * \brief          Set value from integer
+ * \brief          Store integer value in MPI.
  *
- * \param X        MPI to set
- * \param z        Value to use
+ * \param X        The MPI to set. This must be initialized.
+ * \param z        The value to use.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_lset( mbedtls_mpi *X, mbedtls_mpi_sint z );
 
 /**
- * \brief          Get a specific bit from X
+ * \brief          Get a specific bit from an MPI.
  *
- * \param X        MPI to use
- * \param pos      Zero-based index of the bit in X
+ * \param X        The MPI to query. This must be initialized.
+ * \param pos      Zero-based index of the bit to query.
  *
- * \return         Either a 0 or a 1
+ * \return         \c 0 or \c 1 on success, depending on whether bit \c pos
+ *                 of \c X is unset or set.
+ * \return         A negative error code on failure.
  */
 int mbedtls_mpi_get_bit( const mbedtls_mpi *X, size_t pos );
 
 /**
- * \brief          Set a bit of X to a specific value of 0 or 1
+ * \brief          Modify a specific bit in an MPI.
  *
- * \note           Will grow X if necessary to set a bit to 1 in a not yet
- *                 existing limb. Will not grow if bit should be set to 0
+ * \note           This function will grow the target MPI if necessary to set a
+ *                 bit to \c 1 in a not yet existing limb. It will not grow if
+ *                 the bit should be set to \c 0.
  *
- * \param X        MPI to use
- * \param pos      Zero-based index of the bit in X
- * \param val      The value to set the bit to (0 or 1)
+ * \param X        The MPI to modify. This must be initialized.
+ * \param pos      Zero-based index of the bit to modify.
+ * \param val      The desired value of bit \c pos: \c 0 or \c 1.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_BAD_INPUT_DATA if val is not 0 or 1
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_set_bit( mbedtls_mpi *X, size_t pos, unsigned char val );
 
 /**
- * \brief          Return the number of zero-bits before the least significant
- *                 '1' bit
+ * \brief          Return the number of bits of value \c 0 before the
+ *                 least significant bit of value \c 1.
  *
- * Note: Thus also the zero-based index of the least significant '1' bit
+ * \note           This is the same as the zero-based index of
+ *                 the least significant bit of value \c 1.
  *
- * \param X        MPI to use
+ * \param X        The MPI to query.
+ *
+ * \return         The number of bits of value \c 0 before the least significant
+ *                 bit of value \c 1 in \p X.
  */
 size_t mbedtls_mpi_lsb( const mbedtls_mpi *X );
 
 /**
  * \brief          Return the number of bits up to and including the most
- *                 significant '1' bit'
+ *                 significant bit of value \c 1.
  *
- * Note: Thus also the one-based index of the most significant '1' bit
+ * * \note         This is same as the one-based index of the most
+ *                 significant bit of value \c 1.
  *
- * \param X        MPI to use
+ * \param X        The MPI to query. This must point to an initialized MPI.
+ *
+ * \return         The number of bits up to and including the most
+ *                 significant bit of value \c 1.
  */
 size_t mbedtls_mpi_bitlen( const mbedtls_mpi *X );
 
 /**
- * \brief          Return the total size in bytes
+ * \brief          Return the total size of an MPI value in bytes.
  *
- * \param X        MPI to use
+ * \param X        The MPI to use. This must point to an initialized MPI.
+ *
+ * \note           The value returned by this function may be less than
+ *                 the number of bytes used to store \p X internally.
+ *                 This happens if and only if there are trailing bytes
+ *                 of value zero.
+ *
+ * \return         The least number of bytes capable of storing
+ *                 the absolute value of \p X.
  */
 size_t mbedtls_mpi_size( const mbedtls_mpi *X );
 
 /**
- * \brief          Import from an ASCII string
+ * \brief          Import an MPI from an ASCII string.
  *
- * \param X        Destination MPI
- * \param radix    Input numeric base
- * \param s        Null-terminated string buffer
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param radix    The numeric base of the input string.
+ * \param s        Null-terminated string buffer.
  *
- * \return         0 if successful, or a MBEDTLS_ERR_MPI_XXX error code
+ * \return         \c 0 if successful.
+ * \return         A negative error code on failure.
  */
 int mbedtls_mpi_read_string( mbedtls_mpi *X, int radix, const char *s );
 
 /**
- * \brief          Export into an ASCII string
+ * \brief          Export an MPI to an ASCII string.
  *
- * \param X        Source MPI
- * \param radix    Output numeric base
- * \param buf      Buffer to write the string to
- * \param buflen   Length of buf
- * \param olen     Length of the string written, including final NUL byte
+ * \param X        The source MPI. This must point to an initialized MPI.
+ * \param radix    The numeric base of the output string.
+ * \param buf      The buffer to write the string to. This must be writable
+ *                 buffer of length \p buflen Bytes.
+ * \param buflen   The available size in Bytes of \p buf.
+ * \param olen     The address at which to store the length of the string
+ *                 written, including the  final \c NULL byte. This must
+ *                 not be \c NULL.
  *
- * \return         0 if successful, or a MBEDTLS_ERR_MPI_XXX error code.
- *                 *olen is always updated to reflect the amount
- *                 of data that has (or would have) been written.
+ * \note           You can call this function with `buflen == 0` to obtain the
+ *                 minimum required buffer size in `*olen`.
  *
- * \note           Call this function with buflen = 0 to obtain the
- *                 minimum required buffer size in *olen.
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if the target buffer \p buf
+ *                 is too small to hold the value of \p X in the desired base.
+ *                 In this case, `*olen` is nonetheless updated to contain the
+ *                 size of \p buf required for a successful call.
+ * \return         Another negative error code on different kinds of failure.
  */
 int mbedtls_mpi_write_string( const mbedtls_mpi *X, int radix,
                               char *buf, size_t buflen, size_t *olen );
 
 #if defined(MBEDTLS_FS_IO)
 /**
- * \brief          Read MPI from a line in an opened file
+ * \brief          Read an MPI from a line in an opened file.
  *
- * \param X        Destination MPI
- * \param radix    Input numeric base
- * \param fin      Input file handle
- *
- * \return         0 if successful, MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if
- *                 the file read buffer is too small or a
- *                 MBEDTLS_ERR_MPI_XXX error code
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param radix    The numeric base of the string representation used
+ *                 in the source line.
+ * \param fin      The input file handle to use. This must not be \c NULL.
  *
  * \note           On success, this function advances the file stream
  *                 to the end of the current line or to EOF.
  *
- *                 The function returns 0 on an empty line.
+ *                 The function returns \c 0 on an empty line.
  *
  *                 Leading whitespaces are ignored, as is a
- *                 '0x' prefix for radix 16.
+ *                 '0x' prefix for radix \c 16.
  *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if the file read buffer
+ *                 is too small.
+ * \return         Another negative error code on failure.
  */
 int mbedtls_mpi_read_file( mbedtls_mpi *X, int radix, FILE *fin );
 
 /**
- * \brief          Write X into an opened file, or stdout if fout is NULL
+ * \brief          Export an MPI into an opened file.
  *
- * \param p        Prefix, can be NULL
- * \param X        Source MPI
- * \param radix    Output numeric base
- * \param fout     Output file handle (can be NULL)
+ * \param p        A string prefix to emit prior to the MPI data.
+ *                 For example, this might be a label, or "0x" when
+ *                 printing in base \c 16. This may be \c NULL if no prefix
+ *                 is needed.
+ * \param X        The source MPI. This must point to an initialized MPI.
+ * \param radix    The numeric base to be used in the emitted string.
+ * \param fout     The output file handle. This may be \c NULL, in which case
+ *                 the output is written to \c stdout.
  *
- * \return         0 if successful, or a MBEDTLS_ERR_MPI_XXX error code
- *
- * \note           Set fout == NULL to print X on the console.
+ * \return         \c 0 if successful.
+ * \return         A negative error code on failure.
  */
-int mbedtls_mpi_write_file( const char *p, const mbedtls_mpi *X, int radix, FILE *fout );
+int mbedtls_mpi_write_file( const char *p, const mbedtls_mpi *X,
+                            int radix, FILE *fout );
 #endif /* MBEDTLS_FS_IO */
 
 /**
- * \brief          Import X from unsigned binary data, big endian
+ * \brief          Import an MPI from unsigned big endian binary data.
  *
- * \param X        Destination MPI
- * \param buf      Input buffer
- * \param buflen   Input buffer size
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param buf      The input buffer. This must be a readable buffer of length
+ *                 \p buflen Bytes.
+ * \param buflen   The length of the input buffer \p p in Bytes.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_read_binary( mbedtls_mpi *X, const unsigned char *buf, size_t buflen );
+int mbedtls_mpi_read_binary( mbedtls_mpi *X, const unsigned char *buf,
+                             size_t buflen );
+
+/**
+ * \brief          Import X from unsigned binary data, little endian
+ *
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param buf      The input buffer. This must be a readable buffer of length
+ *                 \p buflen Bytes.
+ * \param buflen   The length of the input buffer \p p in Bytes.
+ *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
+ */
+int mbedtls_mpi_read_binary_le( mbedtls_mpi *X,
+                                const unsigned char *buf, size_t buflen );
 
 /**
  * \brief          Export X into unsigned binary data, big endian.
  *                 Always fills the whole buffer, which will start with zeros
  *                 if the number is smaller.
  *
- * \param X        Source MPI
- * \param buf      Output buffer
- * \param buflen   Output buffer size
+ * \param X        The source MPI. This must point to an initialized MPI.
+ * \param buf      The output buffer. This must be a writable buffer of length
+ *                 \p buflen Bytes.
+ * \param buflen   The size of the output buffer \p buf in Bytes.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if buf isn't large enough
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if \p buf isn't
+ *                 large enough to hold the value of \p X.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_write_binary( const mbedtls_mpi *X, unsigned char *buf, size_t buflen );
+int mbedtls_mpi_write_binary( const mbedtls_mpi *X, unsigned char *buf,
+                              size_t buflen );
 
 /**
- * \brief          Left-shift: X <<= count
+ * \brief          Export X into unsigned binary data, little endian.
+ *                 Always fills the whole buffer, which will end with zeros
+ *                 if the number is smaller.
  *
- * \param X        MPI to shift
- * \param count    Amount to shift
+ * \param X        The source MPI. This must point to an initialized MPI.
+ * \param buf      The output buffer. This must be a writable buffer of length
+ *                 \p buflen Bytes.
+ * \param buflen   The size of the output buffer \p buf in Bytes.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if \p buf isn't
+ *                 large enough to hold the value of \p X.
+ * \return         Another negative error code on different kinds of failure.
+ */
+int mbedtls_mpi_write_binary_le( const mbedtls_mpi *X,
+                                 unsigned char *buf, size_t buflen );
+
+/**
+ * \brief          Perform a left-shift on an MPI: X <<= count
+ *
+ * \param X        The MPI to shift. This must point to an initialized MPI.
+ * \param count    The number of bits to shift by.
+ *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
 int mbedtls_mpi_shift_l( mbedtls_mpi *X, size_t count );
 
 /**
- * \brief          Right-shift: X >>= count
+ * \brief          Perform a right-shift on an MPI: X >>= count
  *
- * \param X        MPI to shift
- * \param count    Amount to shift
+ * \param X        The MPI to shift. This must point to an initialized MPI.
+ * \param count    The number of bits to shift by.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
 int mbedtls_mpi_shift_r( mbedtls_mpi *X, size_t count );
 
 /**
- * \brief          Compare unsigned values
+ * \brief          Compare the absolute values of two MPIs.
  *
- * \param X        Left-hand MPI
- * \param Y        Right-hand MPI
+ * \param X        The left-hand MPI. This must point to an initialized MPI.
+ * \param Y        The right-hand MPI. This must point to an initialized MPI.
  *
- * \return         1 if |X| is greater than |Y|,
- *                -1 if |X| is lesser  than |Y| or
- *                 0 if |X| is equal to |Y|
+ * \return         \c 1 if `|X|` is greater than `|Y|`.
+ * \return         \c -1 if `|X|` is lesser than `|Y|`.
+ * \return         \c 0 if `|X|` is equal to `|Y|`.
  */
 int mbedtls_mpi_cmp_abs( const mbedtls_mpi *X, const mbedtls_mpi *Y );
 
 /**
- * \brief          Compare signed values
+ * \brief          Compare two MPIs.
  *
- * \param X        Left-hand MPI
- * \param Y        Right-hand MPI
+ * \param X        The left-hand MPI. This must point to an initialized MPI.
+ * \param Y        The right-hand MPI. This must point to an initialized MPI.
  *
- * \return         1 if X is greater than Y,
- *                -1 if X is lesser  than Y or
- *                 0 if X is equal to Y
+ * \return         \c 1 if \p X is greater than \p Y.
+ * \return         \c -1 if \p X is lesser than \p Y.
+ * \return         \c 0 if \p X is equal to \p Y.
  */
 int mbedtls_mpi_cmp_mpi( const mbedtls_mpi *X, const mbedtls_mpi *Y );
 
 /**
- * \brief          Compare signed values
+ * \brief          Check if an MPI is less than the other in constant time.
  *
- * \param X        Left-hand MPI
- * \param z        The integer value to compare to
+ * \param X        The left-hand MPI. This must point to an initialized MPI
+ *                 with the same allocated length as Y.
+ * \param Y        The right-hand MPI. This must point to an initialized MPI
+ *                 with the same allocated length as X.
+ * \param ret      The result of the comparison:
+ *                 \c 1 if \p X is less than \p Y.
+ *                 \c 0 if \p X is greater than or equal to \p Y.
  *
- * \return         1 if X is greater than z,
- *                -1 if X is lesser  than z or
- *                 0 if X is equal to z
+ * \return         0 on success.
+ * \return         MBEDTLS_ERR_MPI_BAD_INPUT_DATA if the allocated length of
+ *                 the two input MPIs is not the same.
+ */
+int mbedtls_mpi_lt_mpi_ct( const mbedtls_mpi *X, const mbedtls_mpi *Y,
+        unsigned *ret );
+
+/**
+ * \brief          Compare an MPI with an integer.
+ *
+ * \param X        The left-hand MPI. This must point to an initialized MPI.
+ * \param z        The integer value to compare \p X to.
+ *
+ * \return         \c 1 if \p X is greater than \p z.
+ * \return         \c -1 if \p X is lesser than \p z.
+ * \return         \c 0 if \p X is equal to \p z.
  */
 int mbedtls_mpi_cmp_int( const mbedtls_mpi *X, mbedtls_mpi_sint z );
 
 /**
- * \brief          Unsigned addition: X = |A| + |B|
+ * \brief          Perform an unsigned addition of MPIs: X = |A| + |B|
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The first summand. This must point to an initialized MPI.
+ * \param B        The second summand. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_add_abs( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_add_abs( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Unsigned subtraction: X = |A| - |B|
+ * \brief          Perform an unsigned subtraction of MPIs: X = |A| - |B|
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The minuend. This must point to an initialized MPI.
+ * \param B        The subtrahend. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_NEGATIVE_VALUE if B is greater than A
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_NEGATIVE_VALUE if \p B is greater than \p A.
+ * \return         Another negative error code on different kinds of failure.
+ *
  */
-int mbedtls_mpi_sub_abs( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_sub_abs( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Signed addition: X = A + B
+ * \brief          Perform a signed addition of MPIs: X = A + B
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The first summand. This must point to an initialized MPI.
+ * \param B        The second summand. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_add_mpi( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_add_mpi( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Signed subtraction: X = A - B
+ * \brief          Perform a signed subtraction of MPIs: X = A - B
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The minuend. This must point to an initialized MPI.
+ * \param B        The subtrahend. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_sub_mpi( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_sub_mpi( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Signed addition: X = A + b
+ * \brief          Perform a signed addition of an MPI and an integer: X = A + b
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param b        The integer value to add
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The first summand. This must point to an initialized MPI.
+ * \param b        The second summand.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_add_int( mbedtls_mpi *X, const mbedtls_mpi *A, mbedtls_mpi_sint b );
+int mbedtls_mpi_add_int( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         mbedtls_mpi_sint b );
 
 /**
- * \brief          Signed subtraction: X = A - b
+ * \brief          Perform a signed subtraction of an MPI and an integer:
+ *                 X = A - b
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param b        The integer value to subtract
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The minuend. This must point to an initialized MPI.
+ * \param b        The subtrahend.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_sub_int( mbedtls_mpi *X, const mbedtls_mpi *A, mbedtls_mpi_sint b );
+int mbedtls_mpi_sub_int( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         mbedtls_mpi_sint b );
 
 /**
- * \brief          Baseline multiplication: X = A * B
+ * \brief          Perform a multiplication of two MPIs: X = A * B
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The first factor. This must point to an initialized MPI.
+ * \param B        The second factor. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
+ *
  */
-int mbedtls_mpi_mul_mpi( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_mul_mpi( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Baseline multiplication: X = A * b
+ * \brief          Perform a multiplication of an MPI with an unsigned integer:
+ *                 X = A * b
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param b        The unsigned integer value to multiply with
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The first factor. This must point to an initialized MPI.
+ * \param b        The second factor.
  *
- * \note           b is unsigned
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
  */
-int mbedtls_mpi_mul_int( mbedtls_mpi *X, const mbedtls_mpi *A, mbedtls_mpi_uint b );
+int mbedtls_mpi_mul_int( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         mbedtls_mpi_uint b );
 
 /**
- * \brief          Division by mbedtls_mpi: A = Q * B + R
+ * \brief          Perform a division with remainder of two MPIs:
+ *                 A = Q * B + R
  *
- * \param Q        Destination MPI for the quotient
- * \param R        Destination MPI for the rest value
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param Q        The destination MPI for the quotient.
+ *                 This may be \c NULL if the value of the
+ *                 quotient is not needed.
+ * \param R        The destination MPI for the remainder value.
+ *                 This may be \c NULL if the value of the
+ *                 remainder is not needed.
+ * \param A        The dividend. This must point to an initialized MPi.
+ * \param B        The divisor. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if B == 0
- *
- * \note           Either Q or R can be NULL.
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if \p B equals zero.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_div_mpi( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_div_mpi( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Division by int: A = Q * b + R
+ * \brief          Perform a division with remainder of an MPI by an integer:
+ *                 A = Q * b + R
  *
- * \param Q        Destination MPI for the quotient
- * \param R        Destination MPI for the rest value
- * \param A        Left-hand MPI
- * \param b        Integer to divide by
+ * \param Q        The destination MPI for the quotient.
+ *                 This may be \c NULL if the value of the
+ *                 quotient is not needed.
+ * \param R        The destination MPI for the remainder value.
+ *                 This may be \c NULL if the value of the
+ *                 remainder is not needed.
+ * \param A        The dividend. This must point to an initialized MPi.
+ * \param b        The divisor.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if b == 0
- *
- * \note           Either Q or R can be NULL.
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if \p b equals zero.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_div_int( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A, mbedtls_mpi_sint b );
+int mbedtls_mpi_div_int( mbedtls_mpi *Q, mbedtls_mpi *R, const mbedtls_mpi *A,
+                         mbedtls_mpi_sint b );
 
 /**
- * \brief          Modulo: R = A mod B
+ * \brief          Perform a modular reduction. R = A mod B
  *
- * \param R        Destination MPI for the rest value
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * \param R        The destination MPI for the residue value.
+ *                 This must point to an initialized MPI.
+ * \param A        The MPI to compute the residue of.
+ *                 This must point to an initialized MPI.
+ * \param B        The base of the modular reduction.
+ *                 This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if B == 0,
- *                 MBEDTLS_ERR_MPI_NEGATIVE_VALUE if B < 0
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if \p B equals zero.
+ * \return         #MBEDTLS_ERR_MPI_NEGATIVE_VALUE if \p B is negative.
+ * \return         Another negative error code on different kinds of failure.
+ *
  */
-int mbedtls_mpi_mod_mpi( mbedtls_mpi *R, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_mod_mpi( mbedtls_mpi *R, const mbedtls_mpi *A,
+                         const mbedtls_mpi *B );
 
 /**
- * \brief          Modulo: r = A mod b
+ * \brief          Perform a modular reduction with respect to an integer.
+ *                 r = A mod b
  *
- * \param r        Destination mbedtls_mpi_uint
- * \param A        Left-hand MPI
- * \param b        Integer to divide by
+ * \param r        The address at which to store the residue.
+ *                 This must not be \c NULL.
+ * \param A        The MPI to compute the residue of.
+ *                 This must point to an initialized MPi.
+ * \param b        The integer base of the modular reduction.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if b == 0,
- *                 MBEDTLS_ERR_MPI_NEGATIVE_VALUE if b < 0
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if \p b equals zero.
+ * \return         #MBEDTLS_ERR_MPI_NEGATIVE_VALUE if \p b is negative.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_mod_int( mbedtls_mpi_uint *r, const mbedtls_mpi *A, mbedtls_mpi_sint b );
+int mbedtls_mpi_mod_int( mbedtls_mpi_uint *r, const mbedtls_mpi *A,
+                         mbedtls_mpi_sint b );
 
 /**
- * \brief          Sliding-window exponentiation: X = A^E mod N
+ * \brief          Perform a sliding-window exponentiation: X = A^E mod N
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param E        Exponent MPI
- * \param N        Modular MPI
- * \param _RR      Speed-up MPI used for recalculations
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The base of the exponentiation.
+ *                 This must point to an initialized MPI.
+ * \param E        The exponent MPI. This must point to an initialized MPI.
+ * \param N        The base for the modular reduction. This must point to an
+ *                 initialized MPI.
+ * \param _RR      A helper MPI depending solely on \p N which can be used to
+ *                 speed-up multiple modular exponentiations for the same value
+ *                 of \p N. This may be \c NULL. If it is not \c NULL, it must
+ *                 point to an initialized MPI. If it hasn't been used after
+ *                 the call to mbedtls_mpi_init(), this function will compute
+ *                 the helper value and store it in \p _RR for reuse on
+ *                 subsequent calls to this function. Otherwise, the function
+ *                 will assume that \p _RR holds the helper value set by a
+ *                 previous call to mbedtls_mpi_exp_mod(), and reuse it.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_BAD_INPUT_DATA if N is negative or even or
- *                 if E is negative
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \c N is negative or
+ *                 even, or if \c E is negative.
+ * \return         Another negative error code on different kinds of failures.
  *
- * \note           _RR is used to avoid re-computing R*R mod N across
- *                 multiple calls, which speeds up things a bit. It can
- *                 be set to NULL if the extra performance is unneeded.
  */
-int mbedtls_mpi_exp_mod( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *E, const mbedtls_mpi *N, mbedtls_mpi *_RR );
+int mbedtls_mpi_exp_mod( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *E, const mbedtls_mpi *N,
+                         mbedtls_mpi *_RR );
 
 /**
- * \brief          Fill an MPI X with size bytes of random
+ * \brief          Fill an MPI with a number of random bytes.
  *
- * \param X        Destination MPI
- * \param size     Size in bytes
- * \param f_rng    RNG function
- * \param p_rng    RNG parameter
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param size     The number of random bytes to generate.
+ * \param f_rng    The RNG function to use. This must not be \c NULL.
+ * \param p_rng    The RNG parameter to be passed to \p f_rng. This may be
+ *                 \c NULL if \p f_rng doesn't need a context argument.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on failure.
  *
- * \note           The bytes obtained from the PRNG are interpreted
+ * \note           The bytes obtained from the RNG are interpreted
  *                 as a big-endian representation of an MPI; this can
  *                 be relevant in applications like deterministic ECDSA.
  */
@@ -699,58 +868,76 @@
                      int (*f_rng)(void *, unsigned char *, size_t),
                      void *p_rng );
 
-/**
- * \brief          Greatest common divisor: G = gcd(A, B)
+/** Generate a random number uniformly in a range.
  *
- * \param G        Destination MPI
- * \param A        Left-hand MPI
- * \param B        Right-hand MPI
+ * This function generates a random number between \p min inclusive and
+ * \p N exclusive.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
+ * The procedure complies with RFC 6979 §3.3 (deterministic ECDSA)
+ * when the RNG is a suitably parametrized instance of HMAC_DRBG
+ * and \p min is \c 1.
+ *
+ * \note           There are `N - min` possible outputs. The lower bound
+ *                 \p min can be reached, but the upper bound \p N cannot.
+ *
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param min      The minimum value to return.
+ *                 It must be nonnegative.
+ * \param N        The upper bound of the range, exclusive.
+ *                 In other words, this is one plus the maximum value to return.
+ *                 \p N must be strictly larger than \p min.
+ * \param f_rng    The RNG function to use. This must not be \c NULL.
+ * \param p_rng    The RNG parameter to be passed to \p f_rng.
+ *
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p min or \p N is invalid
+ *                 or if they are incompatible.
+ * \return         #MBEDTLS_ERR_MPI_NOT_ACCEPTABLE if the implementation was
+ *                 unable to find a suitable value within a limited number
+ *                 of attempts. This has a negligible probability if \p N
+ *                 is significantly larger than \p min, which is the case
+ *                 for all usual cryptographic applications.
+ * \return         Another negative error code on failure.
  */
-int mbedtls_mpi_gcd( mbedtls_mpi *G, const mbedtls_mpi *A, const mbedtls_mpi *B );
+int mbedtls_mpi_random( mbedtls_mpi *X,
+                        mbedtls_mpi_sint min,
+                        const mbedtls_mpi *N,
+                        int (*f_rng)(void *, unsigned char *, size_t),
+                        void *p_rng );
 
 /**
- * \brief          Modular inverse: X = A^-1 mod N
+ * \brief          Compute the greatest common divisor: G = gcd(A, B)
  *
- * \param X        Destination MPI
- * \param A        Left-hand MPI
- * \param N        Right-hand MPI
+ * \param G        The destination MPI. This must point to an initialized MPI.
+ * \param A        The first operand. This must point to an initialized MPI.
+ * \param B        The second operand. This must point to an initialized MPI.
  *
- * \return         0 if successful,
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_BAD_INPUT_DATA if N is <= 1,
-                   MBEDTLS_ERR_MPI_NOT_ACCEPTABLE if A has no inverse mod N.
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         Another negative error code on different kinds of failure.
  */
-int mbedtls_mpi_inv_mod( mbedtls_mpi *X, const mbedtls_mpi *A, const mbedtls_mpi *N );
+int mbedtls_mpi_gcd( mbedtls_mpi *G, const mbedtls_mpi *A,
+                     const mbedtls_mpi *B );
 
-#if !defined(MBEDTLS_DEPRECATED_REMOVED)
-#if defined(MBEDTLS_DEPRECATED_WARNING)
-#define MBEDTLS_DEPRECATED      __attribute__((deprecated))
-#else
-#define MBEDTLS_DEPRECATED
-#endif
 /**
- * \brief          Miller-Rabin primality test with error probability of
- *                 2<sup>-80</sup>
+ * \brief          Compute the modular inverse: X = A^-1 mod N
  *
- * \deprecated     Superseded by mbedtls_mpi_is_prime_ext() which allows
- *                 specifying the number of Miller-Rabin rounds.
+ * \param X        The destination MPI. This must point to an initialized MPI.
+ * \param A        The MPI to calculate the modular inverse of. This must point
+ *                 to an initialized MPI.
+ * \param N        The base of the modular inversion. This must point to an
+ *                 initialized MPI.
  *
- * \param X        MPI to check
- * \param f_rng    RNG function
- * \param p_rng    RNG parameter
- *
- * \return         0 if successful (probably prime),
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_NOT_ACCEPTABLE if X is not prime
+ * \return         \c 0 if successful.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p N is less than
+ *                 or equal to one.
+ * \return         #MBEDTLS_ERR_MPI_NOT_ACCEPTABLE if \p has no modular inverse
+ *                 with respect to \p N.
  */
-MBEDTLS_DEPRECATED int mbedtls_mpi_is_prime( const mbedtls_mpi *X,
-                          int (*f_rng)(void *, unsigned char *, size_t),
-                          void *p_rng );
-#undef MBEDTLS_DEPRECATED
-#endif /* !MBEDTLS_DEPRECATED_REMOVED */
+int mbedtls_mpi_inv_mod( mbedtls_mpi *X, const mbedtls_mpi *A,
+                         const mbedtls_mpi *N );
 
 /**
  * \brief          Miller-Rabin primality test.
@@ -764,16 +951,20 @@
  *                 case when mbedtls_mpi_gen_prime calls this function), then
  *                 \p rounds can be much lower.
  *
- * \param X        MPI to check
- * \param rounds   Number of bases to perform Miller-Rabin primality test for.
- *                 The probability of returning 0 on a composite is at most
- *                 2<sup>-2*\p rounds</sup>.
- * \param f_rng    RNG function
- * \param p_rng    RNG parameter
+ * \param X        The MPI to check for primality.
+ *                 This must point to an initialized MPI.
+ * \param rounds   The number of bases to perform the Miller-Rabin primality
+ *                 test for. The probability of returning 0 on a composite is
+ *                 at most 2<sup>-2*\p rounds</sup>.
+ * \param f_rng    The RNG function to use. This must not be \c NULL.
+ * \param p_rng    The RNG parameter to be passed to \p f_rng.
+ *                 This may be \c NULL if \p f_rng doesn't use
+ *                 a context parameter.
  *
- * \return         0 if successful (probably prime),
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_NOT_ACCEPTABLE if X is not prime
+ * \return         \c 0 if successful, i.e. \p X is probably prime.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_NOT_ACCEPTABLE if \p X is not prime.
+ * \return         Another negative error code on other kinds of failure.
  */
 int mbedtls_mpi_is_prime_ext( const mbedtls_mpi *X, int rounds,
                               int (*f_rng)(void *, unsigned char *, size_t),
@@ -790,23 +981,30 @@
 } mbedtls_mpi_gen_prime_flag_t;
 
 /**
- * \brief          Prime number generation
+ * \brief          Generate a prime number.
  *
- * \param X        Destination MPI
- * \param nbits    Required size of X in bits
- *                 ( 3 <= nbits <= MBEDTLS_MPI_MAX_BITS )
- * \param flags    Mask of flags of type #mbedtls_mpi_gen_prime_flag_t
- * \param f_rng    RNG function
- * \param p_rng    RNG parameter
+ * \param X        The destination MPI to store the generated prime in.
+ *                 This must point to an initialized MPi.
+ * \param nbits    The required size of the destination MPI in bits.
+ *                 This must be between \c 3 and #MBEDTLS_MPI_MAX_BITS.
+ * \param flags    A mask of flags of type #mbedtls_mpi_gen_prime_flag_t.
+ * \param f_rng    The RNG function to use. This must not be \c NULL.
+ * \param p_rng    The RNG parameter to be passed to \p f_rng.
+ *                 This may be \c NULL if \p f_rng doesn't use
+ *                 a context parameter.
  *
- * \return         0 if successful (probably prime),
- *                 MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
- *                 MBEDTLS_ERR_MPI_BAD_INPUT_DATA if nbits is < 3
+ * \return         \c 0 if successful, in which case \p X holds a
+ *                 probably prime number.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
+ * \return         #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if `nbits` is not between
+ *                 \c 3 and #MBEDTLS_MPI_MAX_BITS.
  */
 int mbedtls_mpi_gen_prime( mbedtls_mpi *X, size_t nbits, int flags,
                    int (*f_rng)(void *, unsigned char *, size_t),
                    void *p_rng );
 
+#if defined(MBEDTLS_SELF_TEST)
+
 /**
  * \brief          Checkup routine
  *
@@ -814,6 +1012,8 @@
  */
 int mbedtls_mpi_self_test( int verbose );
 
+#endif /* MBEDTLS_SELF_TEST */
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/ext/mbedtls-asn1/include/mbedtls/build_info.h b/ext/mbedtls-asn1/include/mbedtls/build_info.h
new file mode 100644
index 0000000..23f85ba
--- /dev/null
+++ b/ext/mbedtls-asn1/include/mbedtls/build_info.h
@@ -0,0 +1,83 @@
+/**
+ * \file build_info.h
+ *
+ * \brief Build-time configuration info
+ *
+ *  Include this file if you need to depend on the
+ *  configuration options defined in mbedtls_config.h or MBEDTLS_CONFIG_FILE
+ */
+ /*
+  *  Copyright The Mbed TLS Contributors
+  *  SPDX-License-Identifier: Apache-2.0
+  *
+  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+  *  not use this file except in compliance with the License.
+  *  You may obtain a copy of the License at
+  *
+  *  http://www.apache.org/licenses/LICENSE-2.0
+  *
+  *  Unless required by applicable law or agreed to in writing, software
+  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  *  See the License for the specific language governing permissions and
+  *  limitations under the License.
+  */
+
+#ifndef MBEDTLS_BUILD_INFO_H
+#define MBEDTLS_BUILD_INFO_H
+
+/*
+ * This set of compile-time defines can be used to determine the version number
+ * of the Mbed TLS library used. Run-time variables for the same can be found in
+ * version.h
+ */
+
+/**
+ * The version number x.y.z is split into three parts.
+ * Major, Minor, Patchlevel
+ */
+#define MBEDTLS_VERSION_MAJOR  3
+#define MBEDTLS_VERSION_MINOR  0
+#define MBEDTLS_VERSION_PATCH  0
+
+/**
+ * The single version number has the following structure:
+ *    MMNNPP00
+ *    Major version | Minor version | Patch version
+ */
+#define MBEDTLS_VERSION_NUMBER         0x03000000
+#define MBEDTLS_VERSION_STRING         "3.0.0"
+#define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 3.0.0"
+
+#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_DEPRECATE)
+#define _CRT_SECURE_NO_DEPRECATE 1
+#endif
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/mbedtls_config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_CONFIG_VERSION) && ( \
+    MBEDTLS_CONFIG_VERSION < 0x03000000 || \
+    MBEDTLS_CONFIG_VERSION > MBEDTLS_VERSION_NUMBER )
+#error "Invalid config version, defined value of MBEDTLS_CONFIG_VERSION is unsupported"
+#endif
+
+/* Target and application specific configurations
+ *
+ * Allow user to override any previous default.
+ *
+ */
+#if defined(MBEDTLS_USER_CONFIG_FILE)
+#include MBEDTLS_USER_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_PSA_CRYPTO_CONFIG)
+#include "mbedtls/config_psa.h"
+#endif
+
+#include "mbedtls/check_config.h"
+
+#endif /* MBEDTLS_BUILD_INFO_H */
diff --git a/ext/mbedtls-asn1/include/mbedtls/check_config.h b/ext/mbedtls-asn1/include/mbedtls/check_config.h
index 425e3ea..e38892d 100644
--- a/ext/mbedtls-asn1/include/mbedtls/check_config.h
+++ b/ext/mbedtls-asn1/include/mbedtls/check_config.h
@@ -4,7 +4,7 @@
  * \brief Consistency checks for configuration options
  */
 /*
- *  Copyright (C) 2006-2018, ARM Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -18,13 +18,6 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
- */
-
-/*
- * It is recommended to include this file from your config.h
- * in order to catch dependency issues early.
  */
 
 #ifndef MBEDTLS_CHECK_CONFIG_H
@@ -44,17 +37,21 @@
 #error "MBEDTLS_PLATFORM_C is required on Windows"
 #endif
 
-/* Fix the config here. Not convenient to put an #ifdef _WIN32 in config.h as
- * it would confuse config.pl. */
+/* Fix the config here. Not convenient to put an #ifdef _WIN32 in mbedtls_config.h as
+ * it would confuse config.py. */
 #if !defined(MBEDTLS_PLATFORM_SNPRINTF_ALT) && \
     !defined(MBEDTLS_PLATFORM_SNPRINTF_MACRO)
 #define MBEDTLS_PLATFORM_SNPRINTF_ALT
 #endif
+
+#if !defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT) && \
+    !defined(MBEDTLS_PLATFORM_VSNPRINTF_MACRO)
+#define MBEDTLS_PLATFORM_VSNPRINTF_ALT
+#endif
 #endif /* _WIN32 */
 
-#if defined(TARGET_LIKE_MBED) && \
-    ( defined(MBEDTLS_NET_C) || defined(MBEDTLS_TIMING_C) )
-#error "The NET and TIMING modules are not available for mbed OS - please use the network and timing functions provided by mbed OS"
+#if defined(TARGET_LIKE_MBED) && defined(MBEDTLS_NET_C)
+#error "The NET module is not available for mbed OS - please use the network functions provided by Mbed OS"
 #endif
 
 #if defined(MBEDTLS_DEPRECATED_WARNING) && \
@@ -78,10 +75,6 @@
 #error "MBEDTLS_DHM_C defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC_COMPAT) && !defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-#error "MBEDTLS_SSL_TRUNCATED_HMAC_COMPAT defined, but not all prerequisites"
-#endif
-
 #if defined(MBEDTLS_CMAC_C) && \
     !defined(MBEDTLS_AES_C) && !defined(MBEDTLS_DES_C)
 #error "MBEDTLS_CMAC_C defined, but not all prerequisites"
@@ -98,6 +91,17 @@
 
 #if defined(MBEDTLS_ECDSA_C) &&            \
     ( !defined(MBEDTLS_ECP_C) ||           \
+      !( defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) || \
+         defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) ||   \
+         defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) ||   \
+         defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) ) || \
       !defined(MBEDTLS_ASN1_PARSE_C) ||    \
       !defined(MBEDTLS_ASN1_WRITE_C) )
 #error "MBEDTLS_ECDSA_C defined, but not all prerequisites"
@@ -109,20 +113,22 @@
 #endif
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)           && \
-    ( defined(MBEDTLS_ECDH_COMPUTE_SHARED_ALT) || \
+    ( defined(MBEDTLS_USE_PSA_CRYPTO)          || \
+      defined(MBEDTLS_ECDH_COMPUTE_SHARED_ALT) || \
       defined(MBEDTLS_ECDH_GEN_PUBLIC_ALT)     || \
       defined(MBEDTLS_ECDSA_SIGN_ALT)          || \
       defined(MBEDTLS_ECDSA_VERIFY_ALT)        || \
       defined(MBEDTLS_ECDSA_GENKEY_ALT)        || \
+      defined(MBEDTLS_ECP_INTERNAL_ALT)        || \
       defined(MBEDTLS_ECP_ALT) )
-#error "MBEDTLS_ECP_RESTARTABLE defined, but it cannot coexist with an alternative ECP implementation"
+#error "MBEDTLS_ECP_RESTARTABLE defined, but it cannot coexist with an alternative or PSA-based ECP implementation"
 #endif
 
 #if defined(MBEDTLS_ECDSA_DETERMINISTIC) && !defined(MBEDTLS_HMAC_DRBG_C)
 #error "MBEDTLS_ECDSA_DETERMINISTIC defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_ECP_C) && ( !defined(MBEDTLS_BIGNUM_C) || (   \
+#if defined(MBEDTLS_ECP_C) && ( !defined(MBEDTLS_BIGNUM_C) || (    \
     !defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) &&                  \
     !defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) &&                  \
     !defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) &&                  \
@@ -133,10 +139,16 @@
     !defined(MBEDTLS_ECP_DP_BP512R1_ENABLED)   &&                  \
     !defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) &&                  \
     !defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) &&                  \
-    !defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) ) )
+    !defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) &&                  \
+    !defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) &&                 \
+    !defined(MBEDTLS_ECP_DP_CURVE448_ENABLED) ) )
 #error "MBEDTLS_ECP_C defined, but not all prerequisites"
 #endif
 
+#if defined(MBEDTLS_PK_PARSE_C) && !defined(MBEDTLS_ASN1_PARSE_C)
+#error "MBEDTLS_PK_PARSE_C defined, but not all prerequesites"
+#endif
+
 #if defined(MBEDTLS_ENTROPY_C) && (!defined(MBEDTLS_SHA512_C) &&      \
                                     !defined(MBEDTLS_SHA256_C))
 #error "MBEDTLS_ENTROPY_C defined, but not all prerequisites"
@@ -155,18 +167,18 @@
 #error "MBEDTLS_ENTROPY_FORCE_SHA256 defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_TEST_NULL_ENTROPY) && \
-    ( !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES) )
-#error "MBEDTLS_TEST_NULL_ENTROPY defined, but not all prerequisites"
+#if defined(__has_feature)
+#if __has_feature(memory_sanitizer)
+#define MBEDTLS_HAS_MEMSAN
 #endif
-#if defined(MBEDTLS_TEST_NULL_ENTROPY) && \
-     ( defined(MBEDTLS_ENTROPY_NV_SEED) || defined(MBEDTLS_ENTROPY_HARDWARE_ALT) || \
-    defined(MBEDTLS_HAVEGE_C) )
-#error "MBEDTLS_TEST_NULL_ENTROPY defined, but entropy sources too"
 #endif
+#if defined(MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN) &&  !defined(MBEDTLS_HAS_MEMSAN)
+#error "MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN requires building with MemorySanitizer"
+#endif
+#undef MBEDTLS_HAS_MEMSAN
 
 #if defined(MBEDTLS_GCM_C) && (                                        \
-        !defined(MBEDTLS_AES_C) && !defined(MBEDTLS_CAMELLIA_C) )
+        !defined(MBEDTLS_AES_C) && !defined(MBEDTLS_CAMELLIA_C) && !defined(MBEDTLS_ARIA_C) )
 #error "MBEDTLS_GCM_C defined, but not all prerequisites"
 #endif
 
@@ -202,8 +214,8 @@
 #error "MBEDTLS_ECP_NORMALIZE_MXZ_ALT defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_HAVEGE_C) && !defined(MBEDTLS_TIMING_C)
-#error "MBEDTLS_HAVEGE_C defined, but not all prerequisites"
+#if defined(MBEDTLS_ECP_NO_FALLBACK) && !defined(MBEDTLS_ECP_INTERNAL_ALT)
+#error "MBEDTLS_ECP_NO_FALLBACK defined, but no alternative implementation enabled"
 #endif
 
 #if defined(MBEDTLS_HKDF_C) && !defined(MBEDTLS_MD_C)
@@ -215,12 +227,14 @@
 #endif
 
 #if defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) &&                 \
-    ( !defined(MBEDTLS_ECDH_C) || !defined(MBEDTLS_X509_CRT_PARSE_C) )
+    ( !defined(MBEDTLS_ECDH_C) || !defined(MBEDTLS_ECDSA_C) ||          \
+      !defined(MBEDTLS_X509_CRT_PARSE_C) )
 #error "MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED defined, but not all prerequisites"
 #endif
 
 #if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) &&                 \
-    ( !defined(MBEDTLS_ECDH_C) || !defined(MBEDTLS_X509_CRT_PARSE_C) )
+    ( !defined(MBEDTLS_ECDH_C) || !defined(MBEDTLS_RSA_C) ||          \
+      !defined(MBEDTLS_X509_CRT_PARSE_C) )
 #error "MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED defined, but not all prerequisites"
 #endif
 
@@ -269,11 +283,27 @@
 #error "MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED defined, but not all prerequisites"
 #endif
 
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED) &&        \
+    !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) &&              \
+    ( !defined(MBEDTLS_SHA256_C) &&                             \
+      !defined(MBEDTLS_SHA512_C) &&                             \
+      !defined(MBEDTLS_SHA1_C) )
+#error "!MBEDTLS_SSL_KEEP_PEER_CERTIFICATE requires MBEDTLS_SHA512_C, MBEDTLS_SHA256_C or MBEDTLS_SHA1_C"
+#endif
+
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C) &&                          \
     ( !defined(MBEDTLS_PLATFORM_C) || !defined(MBEDTLS_PLATFORM_MEMORY) )
 #error "MBEDTLS_MEMORY_BUFFER_ALLOC_C defined, but not all prerequisites"
 #endif
 
+#if defined(MBEDTLS_MEMORY_BACKTRACE) && !defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+#error "MBEDTLS_MEMORY_BACKTRACE defined, but not all prerequesites"
+#endif
+
+#if defined(MBEDTLS_MEMORY_DEBUG) && !defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+#error "MBEDTLS_MEMORY_DEBUG defined, but not all prerequesites"
+#endif
+
 #if defined(MBEDTLS_PADLOCK_C) && !defined(MBEDTLS_HAVE_ASM)
 #error "MBEDTLS_PADLOCK_C defined, but not all prerequisites"
 #endif
@@ -299,10 +329,6 @@
 #error "MBEDTLS_PK_WRITE_C defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_PKCS11_C) && !defined(MBEDTLS_PK_C)
-#error "MBEDTLS_PKCS11_C defined, but not all prerequisites"
-#endif
-
 #if defined(MBEDTLS_PLATFORM_EXIT_ALT) && !defined(MBEDTLS_PLATFORM_C)
 #error "MBEDTLS_PLATFORM_EXIT_ALT defined, but not all prerequisites"
 #endif
@@ -496,6 +522,54 @@
 #error "MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO and MBEDTLS_PLATFORM_STD_NV_SEED_WRITE cannot be defined simultaneously"
 #endif
 
+#if defined(MBEDTLS_PSA_CRYPTO_C) &&                                    \
+    !( ( ( defined(MBEDTLS_CTR_DRBG_C) || defined(MBEDTLS_HMAC_DRBG_C) ) && \
+         defined(MBEDTLS_ENTROPY_C) ) ||                                \
+       defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) )
+#error "MBEDTLS_PSA_CRYPTO_C defined, but not all prerequisites (missing RNG)"
+#endif
+
+#if defined(MBEDTLS_PSA_CRYPTO_SPM) && !defined(MBEDTLS_PSA_CRYPTO_C)
+#error "MBEDTLS_PSA_CRYPTO_SPM defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PSA_CRYPTO_SE_C) &&    \
+    ! ( defined(MBEDTLS_PSA_CRYPTO_C) && \
+        defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) )
+#error "MBEDTLS_PSA_CRYPTO_SE_C defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) &&            \
+    ! defined(MBEDTLS_PSA_CRYPTO_C)
+#error "MBEDTLS_PSA_CRYPTO_STORAGE_C defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PSA_INJECT_ENTROPY) &&      \
+    !( defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) && \
+       defined(MBEDTLS_ENTROPY_NV_SEED) )
+#error "MBEDTLS_PSA_INJECT_ENTROPY defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PSA_INJECT_ENTROPY) &&              \
+    !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
+#error "MBEDTLS_PSA_INJECT_ENTROPY is not compatible with actual entropy sources"
+#endif
+
+#if defined(MBEDTLS_PSA_INJECT_ENTROPY) &&              \
+    defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
+#error "MBEDTLS_PSA_INJECT_ENTROPY is not compatible with MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG"
+#endif
+
+#if defined(MBEDTLS_PSA_ITS_FILE_C) && \
+    !defined(MBEDTLS_FS_IO)
+#error "MBEDTLS_PSA_ITS_FILE_C defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER) && \
+    defined(MBEDTLS_USE_PSA_CRYPTO)
+#error "MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER defined, but it cannot coexist with MBEDTLS_USE_PSA_CRYPTO."
+#endif
+
 #if defined(MBEDTLS_RSA_C) && ( !defined(MBEDTLS_BIGNUM_C) ||         \
     !defined(MBEDTLS_OID_C) )
 #error "MBEDTLS_RSA_C defined, but not all prerequisites"
@@ -511,19 +585,16 @@
 #error "MBEDTLS_X509_RSASSA_PSS_SUPPORT defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_PROTO_SSL3) && ( !defined(MBEDTLS_MD5_C) ||     \
-    !defined(MBEDTLS_SHA1_C) )
-#error "MBEDTLS_SSL_PROTO_SSL3 defined, but not all prerequisites"
+#if defined(MBEDTLS_SHA384_C) && !defined(MBEDTLS_SHA512_C)
+#error "MBEDTLS_SHA384_C defined without MBEDTLS_SHA512_C"
 #endif
 
-#if defined(MBEDTLS_SSL_PROTO_TLS1) && ( !defined(MBEDTLS_MD5_C) ||     \
-    !defined(MBEDTLS_SHA1_C) )
-#error "MBEDTLS_SSL_PROTO_TLS1 defined, but not all prerequisites"
+#if defined(MBEDTLS_SHA224_C) && !defined(MBEDTLS_SHA256_C)
+#error "MBEDTLS_SHA224_C defined without MBEDTLS_SHA256_C"
 #endif
 
-#if defined(MBEDTLS_SSL_PROTO_TLS1_1) && ( !defined(MBEDTLS_MD5_C) ||     \
-    !defined(MBEDTLS_SHA1_C) )
-#error "MBEDTLS_SSL_PROTO_TLS1_1 defined, but not all prerequisites"
+#if defined(MBEDTLS_SHA256_C) && !defined(MBEDTLS_SHA224_C)
+#error "MBEDTLS_SHA256_C defined without MBEDTLS_SHA224_C"
 #endif
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && ( !defined(MBEDTLS_SHA1_C) &&     \
@@ -531,8 +602,28 @@
 #error "MBEDTLS_SSL_PROTO_TLS1_2 defined, but not all prerequisites"
 #endif
 
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL) && ( !defined(MBEDTLS_HKDF_C) && \
+    !defined(MBEDTLS_SHA256_C) && !defined(MBEDTLS_SHA512_C) )
+#error "MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_SSL_PROTO_TLS1_2) &&                                    \
+    !(defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) ||                          \
+      defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) ||                      \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) ||                    \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) ||                  \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) ||                     \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) ||                   \
+      defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) ||                          \
+      defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED) ||                      \
+      defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED) ||                      \
+      defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) ||                    \
+      defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) )
+#error "One or more versions of the TLS protocol are enabled " \
+        "but no key exchange methods defined with MBEDTLS_KEY_EXCHANGE_xxxx"
+#endif
+
 #if defined(MBEDTLS_SSL_PROTO_DTLS)     && \
-    !defined(MBEDTLS_SSL_PROTO_TLS1_1)  && \
     !defined(MBEDTLS_SSL_PROTO_TLS1_2)
 #error "MBEDTLS_SSL_PROTO_DTLS defined, but not all prerequisites"
 #endif
@@ -550,28 +641,10 @@
 #error "MBEDTLS_SSL_SRV_C defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_TLS_C) && (!defined(MBEDTLS_SSL_PROTO_SSL3) && \
-    !defined(MBEDTLS_SSL_PROTO_TLS1) && !defined(MBEDTLS_SSL_PROTO_TLS1_1) && \
-    !defined(MBEDTLS_SSL_PROTO_TLS1_2))
+#if defined(MBEDTLS_SSL_TLS_C) && !defined(MBEDTLS_SSL_PROTO_TLS1_2)
 #error "MBEDTLS_SSL_TLS_C defined, but no protocols are active"
 #endif
 
-#if defined(MBEDTLS_SSL_TLS_C) && (defined(MBEDTLS_SSL_PROTO_SSL3) && \
-    defined(MBEDTLS_SSL_PROTO_TLS1_1) && !defined(MBEDTLS_SSL_PROTO_TLS1))
-#error "Illegal protocol selection"
-#endif
-
-#if defined(MBEDTLS_SSL_TLS_C) && (defined(MBEDTLS_SSL_PROTO_TLS1) && \
-    defined(MBEDTLS_SSL_PROTO_TLS1_2) && !defined(MBEDTLS_SSL_PROTO_TLS1_1))
-#error "Illegal protocol selection"
-#endif
-
-#if defined(MBEDTLS_SSL_TLS_C) && (defined(MBEDTLS_SSL_PROTO_SSL3) && \
-    defined(MBEDTLS_SSL_PROTO_TLS1_2) && (!defined(MBEDTLS_SSL_PROTO_TLS1) || \
-    !defined(MBEDTLS_SSL_PROTO_TLS1_1)))
-#error "Illegal protocol selection"
-#endif
-
 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && !defined(MBEDTLS_SSL_PROTO_DTLS)
 #error "MBEDTLS_SSL_DTLS_HELLO_VERIFY  defined, but not all prerequisites"
 #endif
@@ -586,21 +659,29 @@
 #error "MBEDTLS_SSL_DTLS_ANTI_REPLAY  defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_DTLS_BADMAC_LIMIT) &&                              \
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) &&                              \
     ( !defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_PROTO_DTLS) )
-#error "MBEDTLS_SSL_DTLS_BADMAC_LIMIT  defined, but not all prerequisites"
+#error "MBEDTLS_SSL_DTLS_CONNECTION_ID  defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)            &&                 \
+    defined(MBEDTLS_SSL_CID_IN_LEN_MAX) &&                 \
+    MBEDTLS_SSL_CID_IN_LEN_MAX > 255
+#error "MBEDTLS_SSL_CID_IN_LEN_MAX too large (max 255)"
+#endif
+
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)            &&                  \
+    defined(MBEDTLS_SSL_CID_OUT_LEN_MAX) &&                 \
+    MBEDTLS_SSL_CID_OUT_LEN_MAX > 255
+#error "MBEDTLS_SSL_CID_OUT_LEN_MAX too large (max 255)"
 #endif
 
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) &&   \
-    !defined(MBEDTLS_SSL_PROTO_TLS1)   &&      \
-    !defined(MBEDTLS_SSL_PROTO_TLS1_1) &&      \
     !defined(MBEDTLS_SSL_PROTO_TLS1_2)
 #error "MBEDTLS_SSL_ENCRYPT_THEN_MAC defined, but not all prerequsites"
 #endif
 
 #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) && \
-    !defined(MBEDTLS_SSL_PROTO_TLS1)   &&          \
-    !defined(MBEDTLS_SSL_PROTO_TLS1_1) &&          \
     !defined(MBEDTLS_SSL_PROTO_TLS1_2)
 #error "MBEDTLS_SSL_EXTENDED_MASTER_SECRET defined, but not all prerequsites"
 #endif
@@ -609,11 +690,6 @@
 #error "MBEDTLS_SSL_TICKET_C defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING) && \
-    !defined(MBEDTLS_SSL_PROTO_SSL3) && !defined(MBEDTLS_SSL_PROTO_TLS1)
-#error "MBEDTLS_SSL_CBC_RECORD_SPLITTING defined, but not all prerequisites"
-#endif
-
 #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION) && \
         !defined(MBEDTLS_X509_CRT_PARSE_C)
 #error "MBEDTLS_SSL_SERVER_NAME_INDICATION defined, but not all prerequisites"
@@ -638,6 +714,10 @@
 #endif
 #undef MBEDTLS_THREADING_IMPL
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_PSA_CRYPTO_C)
+#error "MBEDTLS_USE_PSA_CRYPTO defined, but not all prerequisites"
+#endif
+
 #if defined(MBEDTLS_VERSION_FEATURES) && !defined(MBEDTLS_VERSION_C)
 #error "MBEDTLS_VERSION_FEATURES defined, but not all prerequisites"
 #endif
@@ -683,10 +763,75 @@
 #error "MBEDTLS_HAVE_INT32/MBEDTLS_HAVE_INT64 and MBEDTLS_HAVE_ASM cannot be defined simultaneously"
 #endif /* (MBEDTLS_HAVE_INT32 || MBEDTLS_HAVE_INT64) && MBEDTLS_HAVE_ASM */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP) && ( !defined(MBEDTLS_SSL_PROTO_DTLS) )
+#error "MBEDTLS_SSL_DTLS_SRTP defined, but not all prerequisites"
+#endif
+
+#if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH) && ( !defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) )
+#error "MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH defined, but not all prerequisites"
+#endif
+
+
+
+/* Reject attempts to enable options that have been removed and that could
+ * cause a build to succeed but with features removed. */
+
+#if defined(MBEDTLS_HAVEGE_C) //no-check-names
+#error "MBEDTLS_HAVEGE_C was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/2599"
+#endif
+
+#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL) //no-check-names
+#error "MBEDTLS_SSL_HW_RECORD_ACCEL was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4031"
+#endif
+
+#if defined(MBEDTLS_SSL_PROTO_SSL3) //no-check-names
+#error "MBEDTLS_SSL_PROTO_SSL3 (SSL v3.0 support) was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4031"
+#endif
+
+#if defined(MBEDTLS_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO) //no-check-names
+#error "MBEDTLS_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO (SSL v2 ClientHello support) was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4031"
+#endif
+
+#if defined(MBEDTLS_SSL_TRUNCATED_HMAC_COMPAT) //no-check-names
+#error "MBEDTLS_SSL_TRUNCATED_HMAC_COMPAT (compatibility with the buggy implementation of truncated HMAC in Mbed TLS up to 2.7) was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4031"
+#endif
+
+#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES) //no-check-names
+#error "MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES was removed in Mbed TLS 3.0. See the ChangeLog entry if you really need SHA-1-signed certificates."
+#endif
+
+#if defined(MBEDTLS_ZLIB_SUPPORT) //no-check-names
+#error "MBEDTLS_ZLIB_SUPPORT was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4031"
+#endif
+
+#if defined(MBEDTLS_SSL_PROTO_TLS1) //no-check-names
+#error "MBEDTLS_SSL_PROTO_TLS1 (TLS v1.0 support) was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4286"
+#endif
+
+#if defined(MBEDTLS_SSL_PROTO_TLS1_1) //no-check-names
+#error "MBEDTLS_SSL_PROTO_TLS1_1 (TLS v1.1 support) was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4286"
+#endif
+
+#if defined(MBEDTLS_CHECK_PARAMS) //no-check-names
+#error "MBEDTLS_CHECK_PARAMS was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4313"
+#endif
+
+#if defined(MBEDTLS_SSL_CID_PADDING_GRANULARITY) //no-check-names
+#error "MBEDTLS_SSL_CID_PADDING_GRANULARITY was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4335"
+#endif
+
+#if defined(MBEDTLS_SSL_TLS1_3_PADDING_GRANULARITY) //no-check-names
+#error "MBEDTLS_SSL_TLS1_3_PADDING_GRANULARITY was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4335"
+#endif
+
+#if defined(MBEDTLS_SSL_TRUNCATED_HMAC) //no-check-names
+#error "MBEDTLS_SSL_TRUNCATED_HMAC was removed in Mbed TLS 3.0. See https://github.com/ARMmbed/mbedtls/issues/4341"
+#endif
+
 /*
  * Avoid warning from -pedantic. This is a convenient place for this
  * workaround since this is included by every single file before the
- * #if defined(MBEDTLS_xxx_C) that results in emtpy translation units.
+ * #if defined(MBEDTLS_xxx_C) that results in empty translation units.
  */
 typedef int mbedtls_iso_c_forbids_empty_translation_units;
 
diff --git a/ext/mbedtls-asn1/include/mbedtls/ecdsa.h b/ext/mbedtls-asn1/include/mbedtls/ecdsa.h
index 4057828..71b73ee 100644
--- a/ext/mbedtls-asn1/include/mbedtls/ecdsa.h
+++ b/ext/mbedtls-asn1/include/mbedtls/ecdsa.h
@@ -11,7 +11,7 @@
  *
  */
 /*
- *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -25,35 +25,41 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of Mbed TLS (https://tls.mbed.org)
  */
 
 #ifndef MBEDTLS_ECDSA_H
 #define MBEDTLS_ECDSA_H
+#include "mbedtls/private_access.h"
 
-#include "ecp.h"
-#include "md.h"
+#include "mbedtls/build_info.h"
 
-/*
- * RFC-4492 page 20:
+#include "mbedtls/ecp.h"
+#include "mbedtls/md.h"
+
+/**
+ * \brief           Maximum ECDSA signature size for a given curve bit size
  *
+ * \param bits      Curve size in bits
+ * \return          Maximum signature size in bytes
+ *
+ * \note            This macro returns a compile-time constant if its argument
+ *                  is one. It may evaluate its argument multiple times.
+ */
+/*
  *     Ecdsa-Sig-Value ::= SEQUENCE {
  *         r       INTEGER,
  *         s       INTEGER
  *     }
  *
- * Size is at most
- *    1 (tag) + 1 (len) + 1 (initial 0) + ECP_MAX_BYTES for each of r and s,
- *    twice that + 1 (tag) + 2 (len) for the sequence
- * (assuming ECP_MAX_BYTES is less than 126 for r and s,
- * and less than 124 (total len <= 255) for the sequence)
+ * For each of r and s, the value (V) may include an extra initial "0" bit.
  */
-#if MBEDTLS_ECP_MAX_BYTES > 124
-#error "MBEDTLS_ECP_MAX_BYTES bigger than expected, please fix MBEDTLS_ECDSA_MAX_LEN"
-#endif
+#define MBEDTLS_ECDSA_MAX_SIG_LEN( bits )                               \
+    ( /*T,L of SEQUENCE*/ ( ( bits ) >= 61 * 8 ? 3 : 2 ) +              \
+      /*T,L of r,s*/        2 * ( ( ( bits ) >= 127 * 8 ? 3 : 2 ) +     \
+      /*V of r,s*/                ( ( bits ) + 8 ) / 8 ) )
+
 /** The maximal size of an ECDSA signature in Bytes. */
-#define MBEDTLS_ECDSA_MAX_LEN  ( 3 + 2 * ( 3 + MBEDTLS_ECP_MAX_BYTES ) )
+#define MBEDTLS_ECDSA_MAX_LEN  MBEDTLS_ECDSA_MAX_SIG_LEN( MBEDTLS_ECP_MAX_BITS )
 
 #ifdef __cplusplus
 extern "C" {
@@ -98,12 +104,12 @@
  */
 typedef struct
 {
-    mbedtls_ecp_restart_ctx ecp;        /*!<  base context for ECP restart and
+    mbedtls_ecp_restart_ctx MBEDTLS_PRIVATE(ecp);        /*!<  base context for ECP restart and
                                               shared administrative info    */
-    mbedtls_ecdsa_restart_ver_ctx *ver; /*!<  ecdsa_verify() sub-context    */
-    mbedtls_ecdsa_restart_sig_ctx *sig; /*!<  ecdsa_sign() sub-context      */
+    mbedtls_ecdsa_restart_ver_ctx *MBEDTLS_PRIVATE(ver); /*!<  ecdsa_verify() sub-context    */
+    mbedtls_ecdsa_restart_sig_ctx *MBEDTLS_PRIVATE(sig); /*!<  ecdsa_sign() sub-context      */
 #if defined(MBEDTLS_ECDSA_DETERMINISTIC)
-    mbedtls_ecdsa_restart_det_ctx *det; /*!<  ecdsa_sign_det() sub-context  */
+    mbedtls_ecdsa_restart_det_ctx *MBEDTLS_PRIVATE(det); /*!<  ecdsa_sign_det() sub-context  */
 #endif
 } mbedtls_ecdsa_restart_ctx;
 
@@ -115,10 +121,21 @@
 #endif /* MBEDTLS_ECP_RESTARTABLE */
 
 /**
+ * \brief          This function checks whether a given group can be used
+ *                 for ECDSA.
+ *
+ * \param gid      The ECP group ID to check.
+ *
+ * \return         \c 1 if the group can be used, \c 0 otherwise
+ */
+int mbedtls_ecdsa_can_do( mbedtls_ecp_group_id gid );
+
+/**
  * \brief           This function computes the ECDSA signature of a
  *                  previously-hashed message.
  *
- * \note            The deterministic version is usually preferred.
+ * \note            The deterministic version implemented in
+ *                  mbedtls_ecdsa_sign_det_ext() is usually preferred.
  *
  * \note            If the bitlength of the message hash is larger than the
  *                  bitlength of the group order, then the hash is truncated
@@ -128,14 +145,22 @@
  *
  * \see             ecp.h
  *
- * \param grp       The ECP group.
- * \param r         The first output integer.
- * \param s         The second output integer.
- * \param d         The private signing key.
- * \param buf       The message hash.
- * \param blen      The length of \p buf.
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ * \param grp       The context for the elliptic curve to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param r         The MPI context in which to store the first part
+ *                  the signature. This must be initialized.
+ * \param s         The MPI context in which to store the second part
+ *                  the signature. This must be initialized.
+ * \param d         The private signing key. This must be initialized.
+ * \param buf       The content to be signed. This is usually the hash of
+ *                  the original data to be signed. This must be a readable
+ *                  buffer of length \p blen Bytes. It may be \c NULL if
+ *                  \p blen is zero.
+ * \param blen      The length of \p buf in Bytes.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may be
+ *                  \c NULL if \p f_rng doesn't need a context parameter.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX
@@ -162,21 +187,35 @@
  *
  * \see             ecp.h
  *
- * \param grp       The ECP group.
- * \param r         The first output integer.
- * \param s         The second output integer.
- * \param d         The private signing key.
- * \param buf       The message hash.
- * \param blen      The length of \p buf.
- * \param md_alg    The MD algorithm used to hash the message.
+ * \param grp           The context for the elliptic curve to use.
+ *                      This must be initialized and have group parameters
+ *                      set, for example through mbedtls_ecp_group_load().
+ * \param r             The MPI context in which to store the first part
+ *                      the signature. This must be initialized.
+ * \param s             The MPI context in which to store the second part
+ *                      the signature. This must be initialized.
+ * \param d             The private signing key. This must be initialized
+ *                      and setup, for example through mbedtls_ecp_gen_privkey().
+ * \param buf           The hashed content to be signed. This must be a readable
+ *                      buffer of length \p blen Bytes. It may be \c NULL if
+ *                      \p blen is zero.
+ * \param blen          The length of \p buf in Bytes.
+ * \param md_alg        The hash algorithm used to hash the original data.
+ * \param f_rng_blind   The RNG function used for blinding. This must not be
+ *                      \c NULL.
+ * \param p_rng_blind   The RNG context to be passed to \p f_rng. This may be
+ *                      \c NULL if \p f_rng doesn't need a context parameter.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX
  *                  error code on failure.
  */
-int mbedtls_ecdsa_sign_det( mbedtls_ecp_group *grp, mbedtls_mpi *r, mbedtls_mpi *s,
-                    const mbedtls_mpi *d, const unsigned char *buf, size_t blen,
-                    mbedtls_md_type_t md_alg );
+int mbedtls_ecdsa_sign_det_ext( mbedtls_ecp_group *grp, mbedtls_mpi *r,
+                            mbedtls_mpi *s, const mbedtls_mpi *d,
+                            const unsigned char *buf, size_t blen,
+                            mbedtls_md_type_t md_alg,
+                            int (*f_rng_blind)(void *, unsigned char *, size_t),
+                            void *p_rng_blind );
 #endif /* MBEDTLS_ECDSA_DETERMINISTIC */
 
 /**
@@ -191,12 +230,19 @@
  *
  * \see             ecp.h
  *
- * \param grp       The ECP group.
- * \param buf       The message hash.
- * \param blen      The length of \p buf.
- * \param Q         The public key to use for verification.
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param buf       The hashed content that was signed. This must be a readable
+ *                  buffer of length \p blen Bytes. It may be \c NULL if
+ *                  \p blen is zero.
+ * \param blen      The length of \p buf in Bytes.
+ * \param Q         The public key to use for verification. This must be
+ *                  initialized and setup.
  * \param r         The first integer of the signature.
+ *                  This must be initialized.
  * \param s         The second integer of the signature.
+ *                  This must be initialized.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the signature
@@ -205,8 +251,9 @@
  *                  error code on failure for any other reason.
  */
 int mbedtls_ecdsa_verify( mbedtls_ecp_group *grp,
-                  const unsigned char *buf, size_t blen,
-                  const mbedtls_ecp_point *Q, const mbedtls_mpi *r, const mbedtls_mpi *s);
+                          const unsigned char *buf, size_t blen,
+                          const mbedtls_ecp_point *Q, const mbedtls_mpi *r,
+                          const mbedtls_mpi *s);
 
 /**
  * \brief           This function computes the ECDSA signature and writes it
@@ -223,11 +270,6 @@
  *                  of the Digital Signature Algorithm (DSA) and Elliptic
  *                  Curve Digital Signature Algorithm (ECDSA)</em>.
  *
- * \note            The \p sig buffer must be at least twice as large as the
- *                  size of the curve used, plus 9. For example, 73 Bytes if
- *                  a 256-bit curve is used. A buffer length of
- *                  #MBEDTLS_ECDSA_MAX_LEN is always safe.
- *
  * \note            If the bitlength of the message hash is larger than the
  *                  bitlength of the group order, then the hash is truncated as
  *                  defined in <em>Standards for Efficient Cryptography Group
@@ -236,22 +278,36 @@
  *
  * \see             ecp.h
  *
- * \param ctx       The ECDSA context.
+ * \param ctx       The ECDSA context to use. This must be initialized
+ *                  and have a group and private key bound to it, for example
+ *                  via mbedtls_ecdsa_genkey() or mbedtls_ecdsa_from_keypair().
  * \param md_alg    The message digest that was used to hash the message.
- * \param hash      The message hash.
- * \param hlen      The length of the hash.
- * \param sig       The buffer that holds the signature.
- * \param slen      The length of the signature written.
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ * \param hash      The message hash to be signed. This must be a readable
+ *                  buffer of length \p blen Bytes.
+ * \param hlen      The length of the hash \p hash in Bytes.
+ * \param sig       The buffer to which to write the signature. This must be a
+ *                  writable buffer of length at least twice as large as the
+ *                  size of the curve used, plus 9. For example, 73 Bytes if
+ *                  a 256-bit curve is used. A buffer length of
+ *                  #MBEDTLS_ECDSA_MAX_LEN is always safe.
+ * \param sig_size  The size of the \p sig buffer in bytes.
+ * \param slen      The address at which to store the actual length of
+ *                  the signature written. Must not be \c NULL.
+ * \param f_rng     The RNG function. This must not be \c NULL if
+ *                  #MBEDTLS_ECDSA_DETERMINISTIC is unset. Otherwise,
+ *                  it is used only for blinding and may be set to \c NULL, but
+ *                  doing so is DEPRECATED.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may be
+ *                  \c NULL if \p f_rng is \c NULL or doesn't use a context.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX, \c MBEDTLS_ERR_MPI_XXX or
  *                  \c MBEDTLS_ERR_ASN1_XXX error code on failure.
  */
-int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx, mbedtls_md_type_t md_alg,
+int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx,
+                                   mbedtls_md_type_t md_alg,
                            const unsigned char *hash, size_t hlen,
-                           unsigned char *sig, size_t *slen,
+                           unsigned char *sig, size_t sig_size, size_t *slen,
                            int (*f_rng)(void *, unsigned char *, size_t),
                            void *p_rng );
 
@@ -265,15 +321,29 @@
  *                  but it can return early and restart according to the limit
  *                  set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
  *
- * \param ctx       The ECDSA context.
+ * \param ctx       The ECDSA context to use. This must be initialized
+ *                  and have a group and private key bound to it, for example
+ *                  via mbedtls_ecdsa_genkey() or mbedtls_ecdsa_from_keypair().
  * \param md_alg    The message digest that was used to hash the message.
- * \param hash      The message hash.
- * \param hlen      The length of the hash.
- * \param sig       The buffer that holds the signature.
- * \param slen      The length of the signature written.
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
- * \param rs_ctx    The restart context (NULL disables restart).
+ * \param hash      The message hash to be signed. This must be a readable
+ *                  buffer of length \p blen Bytes.
+ * \param hlen      The length of the hash \p hash in Bytes.
+ * \param sig       The buffer to which to write the signature. This must be a
+ *                  writable buffer of length at least twice as large as the
+ *                  size of the curve used, plus 9. For example, 73 Bytes if
+ *                  a 256-bit curve is used. A buffer length of
+ *                  #MBEDTLS_ECDSA_MAX_LEN is always safe.
+ * \param sig_size  The size of the \p sig buffer in bytes.
+ * \param slen      The address at which to store the actual length of
+ *                  the signature written. Must not be \c NULL.
+ * \param f_rng     The RNG function. This must not be \c NULL if
+ *                  #MBEDTLS_ECDSA_DETERMINISTIC is unset. Otherwise,
+ *                  it is unused and may be set to \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may be
+ *                  \c NULL if \p f_rng is \c NULL or doesn't use a context.
+ * \param rs_ctx    The restart context to use. This may be \c NULL to disable
+ *                  restarting. If it is not \c NULL, it must point to an
+ *                  initialized restart context.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
@@ -284,66 +354,11 @@
 int mbedtls_ecdsa_write_signature_restartable( mbedtls_ecdsa_context *ctx,
                            mbedtls_md_type_t md_alg,
                            const unsigned char *hash, size_t hlen,
-                           unsigned char *sig, size_t *slen,
+                           unsigned char *sig, size_t sig_size, size_t *slen,
                            int (*f_rng)(void *, unsigned char *, size_t),
                            void *p_rng,
                            mbedtls_ecdsa_restart_ctx *rs_ctx );
 
-#if defined(MBEDTLS_ECDSA_DETERMINISTIC)
-#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
-#if defined(MBEDTLS_DEPRECATED_WARNING)
-#define MBEDTLS_DEPRECATED    __attribute__((deprecated))
-#else
-#define MBEDTLS_DEPRECATED
-#endif
-/**
- * \brief           This function computes an ECDSA signature and writes
- *                  it to a buffer, serialized as defined in <em>RFC-4492:
- *                  Elliptic Curve Cryptography (ECC) Cipher Suites for
- *                  Transport Layer Security (TLS)</em>.
- *
- *                  The deterministic version is defined in <em>RFC-6979:
- *                  Deterministic Usage of the Digital Signature Algorithm (DSA)
- *                  and Elliptic Curve Digital Signature Algorithm (ECDSA)</em>.
- *
- * \warning         It is not thread-safe to use the same context in
- *                  multiple threads.
- *
- * \note            The \p sig buffer must be at least twice as large as the
- *                  size of the curve used, plus 9. For example, 73 Bytes if a
- *                  256-bit curve is used. A buffer length of
- *                  #MBEDTLS_ECDSA_MAX_LEN is always safe.
- *
- * \note            If the bitlength of the message hash is larger than the
- *                  bitlength of the group order, then the hash is truncated as
- *                  defined in <em>Standards for Efficient Cryptography Group
- *                  (SECG): SEC1 Elliptic Curve Cryptography</em>, section
- *                  4.1.3, step 5.
- *
- * \see             ecp.h
- *
- * \deprecated      Superseded by mbedtls_ecdsa_write_signature() in
- *                  Mbed TLS version 2.0 and later.
- *
- * \param ctx       The ECDSA context.
- * \param hash      The message hash.
- * \param hlen      The length of the hash.
- * \param sig       The buffer that holds the signature.
- * \param slen      The length of the signature written.
- * \param md_alg    The MD algorithm used to hash the message.
- *
- * \return          \c 0 on success.
- * \return          An \c MBEDTLS_ERR_ECP_XXX, \c MBEDTLS_ERR_MPI_XXX or
- *                  \c MBEDTLS_ERR_ASN1_XXX error code on failure.
- */
-int mbedtls_ecdsa_write_signature_det( mbedtls_ecdsa_context *ctx,
-                               const unsigned char *hash, size_t hlen,
-                               unsigned char *sig, size_t *slen,
-                               mbedtls_md_type_t md_alg ) MBEDTLS_DEPRECATED;
-#undef MBEDTLS_DEPRECATED
-#endif /* MBEDTLS_DEPRECATED_REMOVED */
-#endif /* MBEDTLS_ECDSA_DETERMINISTIC */
-
 /**
  * \brief           This function reads and verifies an ECDSA signature.
  *
@@ -355,11 +370,14 @@
  *
  * \see             ecp.h
  *
- * \param ctx       The ECDSA context.
- * \param hash      The message hash.
- * \param hlen      The size of the hash.
- * \param sig       The signature to read and verify.
- * \param slen      The size of \p sig.
+ * \param ctx       The ECDSA context to use. This must be initialized
+ *                  and have a group and public key bound to it.
+ * \param hash      The message hash that was signed. This must be a readable
+ *                  buffer of length \p size Bytes.
+ * \param hlen      The size of the hash \p hash.
+ * \param sig       The signature to read and verify. This must be a readable
+ *                  buffer of length \p slen Bytes.
+ * \param slen      The size of \p sig in Bytes.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if signature is invalid.
@@ -382,12 +400,17 @@
  *                  but it can return early and restart according to the limit
  *                  set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
  *
- * \param ctx       The ECDSA context.
- * \param hash      The message hash.
- * \param hlen      The size of the hash.
- * \param sig       The signature to read and verify.
- * \param slen      The size of \p sig.
- * \param rs_ctx    The restart context (NULL disables restart).
+ * \param ctx       The ECDSA context to use. This must be initialized
+ *                  and have a group and public key bound to it.
+ * \param hash      The message hash that was signed. This must be a readable
+ *                  buffer of length \p size Bytes.
+ * \param hlen      The size of the hash \p hash.
+ * \param sig       The signature to read and verify. This must be a readable
+ *                  buffer of length \p slen Bytes.
+ * \param slen      The size of \p sig in Bytes.
+ * \param rs_ctx    The restart context to use. This may be \c NULL to disable
+ *                  restarting. If it is not \c NULL, it must point to an
+ *                  initialized restart context.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if signature is invalid.
@@ -409,10 +432,12 @@
  * \see            ecp.h
  *
  * \param ctx      The ECDSA context to store the keypair in.
+ *                 This must be initialized.
  * \param gid      The elliptic curve to use. One of the various
  *                 \c MBEDTLS_ECP_DP_XXX macros depending on configuration.
- * \param f_rng    The RNG function.
- * \param p_rng    The RNG context.
+ * \param f_rng    The RNG function to use. This must not be \c NULL.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be
+ *                 \c NULL if \p f_rng doesn't need a context argument.
  *
  * \return         \c 0 on success.
  * \return         An \c MBEDTLS_ERR_ECP_XXX code on failure.
@@ -421,40 +446,55 @@
                   int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 /**
- * \brief           This function sets an ECDSA context from an EC key pair.
+ * \brief           This function sets up an ECDSA context from an EC key pair.
  *
  * \see             ecp.h
  *
- * \param ctx       The ECDSA context to set.
- * \param key       The EC key to use.
+ * \param ctx       The ECDSA context to setup. This must be initialized.
+ * \param key       The EC key to use. This must be initialized and hold
+ *                  a private-public key pair or a public key. In the former
+ *                  case, the ECDSA context may be used for signature creation
+ *                  and verification after this call. In the latter case, it
+ *                  may be used for signature verification.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX code on failure.
  */
-int mbedtls_ecdsa_from_keypair( mbedtls_ecdsa_context *ctx, const mbedtls_ecp_keypair *key );
+int mbedtls_ecdsa_from_keypair( mbedtls_ecdsa_context *ctx,
+                                const mbedtls_ecp_keypair *key );
 
 /**
  * \brief           This function initializes an ECDSA context.
  *
  * \param ctx       The ECDSA context to initialize.
+ *                  This must not be \c NULL.
  */
 void mbedtls_ecdsa_init( mbedtls_ecdsa_context *ctx );
 
 /**
  * \brief           This function frees an ECDSA context.
  *
- * \param ctx       The ECDSA context to free.
+ * \param ctx       The ECDSA context to free. This may be \c NULL,
+ *                  in which case this function does nothing. If it
+ *                  is not \c NULL, it must be initialized.
  */
 void mbedtls_ecdsa_free( mbedtls_ecdsa_context *ctx );
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)
 /**
- * \brief           Initialize a restart context
+ * \brief           Initialize a restart context.
+ *
+ * \param ctx       The restart context to initialize.
+ *                  This must not be \c NULL.
  */
 void mbedtls_ecdsa_restart_init( mbedtls_ecdsa_restart_ctx *ctx );
 
 /**
- * \brief           Free the components of a restart context
+ * \brief           Free the components of a restart context.
+ *
+ * \param ctx       The restart context to free. This may be \c NULL,
+ *                  in which case this function does nothing. If it
+ *                  is not \c NULL, it must be initialized.
  */
 void mbedtls_ecdsa_restart_free( mbedtls_ecdsa_restart_ctx *ctx );
 #endif /* MBEDTLS_ECP_RESTARTABLE */
diff --git a/ext/mbedtls-asn1/include/mbedtls/ecp.h b/ext/mbedtls-asn1/include/mbedtls/ecp.h
index 2fb1af4..b87114b 100644
--- a/ext/mbedtls-asn1/include/mbedtls/ecp.h
+++ b/ext/mbedtls-asn1/include/mbedtls/ecp.h
@@ -15,7 +15,7 @@
  */
 
 /*
- *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -29,14 +29,15 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of Mbed TLS (https://tls.mbed.org)
  */
 
 #ifndef MBEDTLS_ECP_H
 #define MBEDTLS_ECP_H
+#include "mbedtls/private_access.h"
 
-#include "bignum.h"
+#include "mbedtls/build_info.h"
+
+#include "mbedtls/bignum.h"
 
 /*
  * ECP error codes
@@ -49,12 +50,28 @@
 #define MBEDTLS_ERR_ECP_RANDOM_FAILED                     -0x4D00  /**< Generation of random value, such as ephemeral key, failed. */
 #define MBEDTLS_ERR_ECP_INVALID_KEY                       -0x4C80  /**< Invalid private or public key. */
 #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH                  -0x4C00  /**< The buffer contains a valid signature followed by more data. */
-
-/* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED                   -0x4B80  /**< The ECP hardware accelerator failed. */
-
 #define MBEDTLS_ERR_ECP_IN_PROGRESS                       -0x4B00  /**< Operation in progress, call again with the same parameters to continue. */
 
+/* Flags indicating whether to include code that is specific to certain
+ * types of curves. These flags are for internal library use only. */
+#if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
+#define MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED
+#endif
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) || \
+    defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+#define MBEDTLS_ECP_MONTGOMERY_ENABLED
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -68,6 +85,22 @@
  * parameters. Therefore, only standardized domain parameters from trusted
  * sources should be used. See mbedtls_ecp_group_load().
  */
+/* Note: when adding a new curve:
+ * - Add it at the end of this enum, otherwise you'll break the ABI by
+ *   changing the numerical value for existing curves.
+ * - Increment MBEDTLS_ECP_DP_MAX below if needed.
+ * - Update the calculation of MBEDTLS_ECP_MAX_BITS below.
+ * - Add the corresponding MBEDTLS_ECP_DP_xxx_ENABLED macro definition to
+ *   mbedtls_config.h.
+ * - List the curve as a dependency of MBEDTLS_ECP_C and
+ *   MBEDTLS_ECDSA_C if supported in check_config.h.
+ * - Add the curve to the appropriate curve type macro
+ *   MBEDTLS_ECP_yyy_ENABLED above.
+ * - Add the necessary definitions to ecp_curves.c.
+ * - Add the curve to the ecp_supported_curves array in ecp.c.
+ * - Add the curve to applicable profiles in x509_crt.c.
+ * - Add the curve to applicable presets in ssl_tls.c.
+ */
 typedef enum
 {
     MBEDTLS_ECP_DP_NONE = 0,       /*!< Curve not defined. */
@@ -93,15 +126,25 @@
  */
 #define MBEDTLS_ECP_DP_MAX     12
 
+/*
+ * Curve types
+ */
+typedef enum
+{
+    MBEDTLS_ECP_TYPE_NONE = 0,
+    MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS,    /* y^2 = x^3 + a x + b      */
+    MBEDTLS_ECP_TYPE_MONTGOMERY,           /* y^2 = x^3 + a x^2 + x    */
+} mbedtls_ecp_curve_type;
+
 /**
  * Curve information, for use by other modules.
  */
 typedef struct mbedtls_ecp_curve_info
 {
-    mbedtls_ecp_group_id grp_id;    /*!< An internal identifier. */
-    uint16_t tls_id;                /*!< The TLS NamedCurve identifier. */
-    uint16_t bit_size;              /*!< The curve size in bits. */
-    const char *name;               /*!< A human-friendly name. */
+    mbedtls_ecp_group_id MBEDTLS_PRIVATE(grp_id);    /*!< An internal identifier. */
+    uint16_t MBEDTLS_PRIVATE(tls_id);                /*!< The TLS NamedCurve identifier. */
+    uint16_t MBEDTLS_PRIVATE(bit_size);              /*!< The curve size in bits. */
+    const char *MBEDTLS_PRIVATE(name);               /*!< A human-friendly name. */
 } mbedtls_ecp_curve_info;
 
 /**
@@ -117,9 +160,9 @@
  */
 typedef struct mbedtls_ecp_point
 {
-    mbedtls_mpi X;          /*!< The X coordinate of the ECP point. */
-    mbedtls_mpi Y;          /*!< The Y coordinate of the ECP point. */
-    mbedtls_mpi Z;          /*!< The Z coordinate of the ECP point. */
+    mbedtls_mpi MBEDTLS_PRIVATE(X);          /*!< The X coordinate of the ECP point. */
+    mbedtls_mpi MBEDTLS_PRIVATE(Y);          /*!< The Y coordinate of the ECP point. */
+    mbedtls_mpi MBEDTLS_PRIVATE(Z);          /*!< The Z coordinate of the ECP point. */
 }
 mbedtls_ecp_point;
 
@@ -159,6 +202,16 @@
  * additions or subtractions. Therefore, it is only an approximative modular
  * reduction. It must return 0 on success and non-zero on failure.
  *
+ * \note        Alternative implementations of the ECP module must obey the
+ *              following constraints.
+ *              * Group IDs must be distinct: if two group structures have
+ *                the same ID, then they must be identical.
+ *              * The fields \c id, \c P, \c A, \c B, \c G, \c N,
+ *                \c pbits and \c nbits must have the same type and semantics
+ *                as in the built-in implementation.
+ *                They must be available for reading, but direct modification
+ *                of these fields does not need to be supported.
+ *                They do not need to be at the same offset in the structure.
  */
 typedef struct mbedtls_ecp_group
 {
@@ -174,17 +227,114 @@
     size_t nbits;               /*!< For Short Weierstrass: The number of bits in \p P.
                                      For Montgomery curves: the number of bits in the
                                      private keys. */
-    unsigned int h;             /*!< \internal 1 if the constants are static. */
-    int (*modp)(mbedtls_mpi *); /*!< The function for fast pseudo-reduction
+    /* End of public fields */
+
+    unsigned int MBEDTLS_PRIVATE(h);             /*!< \internal 1 if the constants are static. */
+    int (*MBEDTLS_PRIVATE(modp))(mbedtls_mpi *); /*!< The function for fast pseudo-reduction
                                      mod \p P (see above).*/
-    int (*t_pre)(mbedtls_ecp_point *, void *);  /*!< Unused. */
-    int (*t_post)(mbedtls_ecp_point *, void *); /*!< Unused. */
-    void *t_data;               /*!< Unused. */
-    mbedtls_ecp_point *T;       /*!< Pre-computed points for ecp_mul_comb(). */
-    size_t T_size;              /*!< The number of pre-computed points. */
+    int (*MBEDTLS_PRIVATE(t_pre))(mbedtls_ecp_point *, void *);  /*!< Unused. */
+    int (*MBEDTLS_PRIVATE(t_post))(mbedtls_ecp_point *, void *); /*!< Unused. */
+    void *MBEDTLS_PRIVATE(t_data);               /*!< Unused. */
+    mbedtls_ecp_point *MBEDTLS_PRIVATE(T);       /*!< Pre-computed points for ecp_mul_comb(). */
+    size_t MBEDTLS_PRIVATE(T_size);              /*!< The number of dynamic allocated pre-computed points. */
 }
 mbedtls_ecp_group;
 
+/**
+ * \name SECTION: Module settings
+ *
+ * The configuration options you can set for this module are in this section.
+ * Either change them in mbedtls_config.h, or define them using the compiler command line.
+ * \{
+ */
+
+#if !defined(MBEDTLS_ECP_WINDOW_SIZE)
+/*
+ * Maximum "window" size used for point multiplication.
+ * Default: a point where higher memory usage yields disminishing performance
+ *          returns.
+ * Minimum value: 2. Maximum value: 7.
+ *
+ * Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) )
+ * points used for point multiplication. This value is directly tied to EC
+ * peak memory usage, so decreasing it by one should roughly cut memory usage
+ * by two (if large curves are in use).
+ *
+ * Reduction in size may reduce speed, but larger curves are impacted first.
+ * Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1):
+ *      w-size:     6       5       4       3       2
+ *      521       145     141     135     120      97
+ *      384       214     209     198     177     146
+ *      256       320     320     303     262     226
+ *      224       475     475     453     398     342
+ *      192       640     640     633     587     476
+ */
+#define MBEDTLS_ECP_WINDOW_SIZE    4   /**< The maximum window size used. */
+#endif /* MBEDTLS_ECP_WINDOW_SIZE */
+
+#if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM)
+/*
+ * Trade code size for speed on fixed-point multiplication.
+ *
+ * This speeds up repeated multiplication of the generator (that is, the
+ * multiplication in ECDSA signatures, and half of the multiplications in
+ * ECDSA verification and ECDHE) by a factor roughly 3 to 4.
+ *
+ * For each n-bit Short Weierstrass curve that is enabled, this adds 4n bytes
+ * of code size if n < 384 and 8n otherwise.
+ *
+ * Change this value to 0 to reduce code size.
+ */
+#define MBEDTLS_ECP_FIXED_POINT_OPTIM  1   /**< Enable fixed-point speed-up. */
+#endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */
+
+/* \} name SECTION: Module settings */
+
+#else  /* MBEDTLS_ECP_ALT */
+#include "ecp_alt.h"
+#endif /* MBEDTLS_ECP_ALT */
+
+/**
+ * The maximum size of the groups, that is, of \c N and \c P.
+ */
+#if !defined(MBEDTLS_ECP_C)
+/* Dummy definition to help code that has optional ECP support and
+ * defines an MBEDTLS_ECP_MAX_BYTES-sized array unconditionally. */
+#define MBEDTLS_ECP_MAX_BITS 1
+/* Note: the curves must be listed in DECREASING size! */
+#elif defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 521
+#elif defined(MBEDTLS_ECP_DP_BP512R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 512
+#elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 448
+#elif defined(MBEDTLS_ECP_DP_BP384R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 384
+#elif defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 384
+#elif defined(MBEDTLS_ECP_DP_BP256R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 256
+#elif defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 256
+#elif defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 256
+#elif defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 255
+#elif defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 225 // n is slightly above 2^224
+#elif defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 224
+#elif defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 192
+#elif defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
+#define MBEDTLS_ECP_MAX_BITS 192
+#else
+#error "Missing definition of MBEDTLS_ECP_MAX_BITS"
+#endif
+
+#define MBEDTLS_ECP_MAX_BYTES    ( ( MBEDTLS_ECP_MAX_BITS + 7 ) / 8 )
+#define MBEDTLS_ECP_MAX_PT_LEN   ( 2 * MBEDTLS_ECP_MAX_BYTES + 1 )
+
 #if defined(MBEDTLS_ECP_RESTARTABLE)
 
 /**
@@ -206,10 +356,10 @@
  */
 typedef struct
 {
-    unsigned ops_done;                  /*!<  current ops count             */
-    unsigned depth;                     /*!<  call depth (0 = top-level)    */
-    mbedtls_ecp_restart_mul_ctx *rsm;   /*!<  ecp_mul_comb() sub-context    */
-    mbedtls_ecp_restart_muladd_ctx *ma; /*!<  ecp_muladd() sub-context      */
+    unsigned MBEDTLS_PRIVATE(ops_done);                  /*!<  current ops count             */
+    unsigned MBEDTLS_PRIVATE(depth);                     /*!<  call depth (0 = top-level)    */
+    mbedtls_ecp_restart_mul_ctx *MBEDTLS_PRIVATE(rsm);   /*!<  ecp_mul_comb() sub-context    */
+    mbedtls_ecp_restart_muladd_ctx *MBEDTLS_PRIVATE(ma); /*!<  ecp_muladd() sub-context      */
 } mbedtls_ecp_restart_ctx;
 
 /*
@@ -250,68 +400,6 @@
 #endif /* MBEDTLS_ECP_RESTARTABLE */
 
 /**
- * \name SECTION: Module settings
- *
- * The configuration options you can set for this module are in this section.
- * Either change them in config.h, or define them using the compiler command line.
- * \{
- */
-
-#if !defined(MBEDTLS_ECP_MAX_BITS)
-/**
- * The maximum size of the groups, that is, of \c N and \c P.
- */
-#define MBEDTLS_ECP_MAX_BITS     521   /**< The maximum size of groups, in bits. */
-#endif
-
-#define MBEDTLS_ECP_MAX_BYTES    ( ( MBEDTLS_ECP_MAX_BITS + 7 ) / 8 )
-#define MBEDTLS_ECP_MAX_PT_LEN   ( 2 * MBEDTLS_ECP_MAX_BYTES + 1 )
-
-#if !defined(MBEDTLS_ECP_WINDOW_SIZE)
-/*
- * Maximum "window" size used for point multiplication.
- * Default: 6.
- * Minimum value: 2. Maximum value: 7.
- *
- * Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) )
- * points used for point multiplication. This value is directly tied to EC
- * peak memory usage, so decreasing it by one should roughly cut memory usage
- * by two (if large curves are in use).
- *
- * Reduction in size may reduce speed, but larger curves are impacted first.
- * Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1):
- *      w-size:     6       5       4       3       2
- *      521       145     141     135     120      97
- *      384       214     209     198     177     146
- *      256       320     320     303     262     226
- *      224       475     475     453     398     342
- *      192       640     640     633     587     476
- */
-#define MBEDTLS_ECP_WINDOW_SIZE    6   /**< The maximum window size used. */
-#endif /* MBEDTLS_ECP_WINDOW_SIZE */
-
-#if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM)
-/*
- * Trade memory for speed on fixed-point multiplication.
- *
- * This speeds up repeated multiplication of the generator (that is, the
- * multiplication in ECDSA signatures, and half of the multiplications in
- * ECDSA verification and ECDHE) by a factor roughly 3 to 4.
- *
- * The cost is increasing EC peak memory usage by a factor roughly 2.
- *
- * Change this value to 0 to reduce peak memory usage.
- */
-#define MBEDTLS_ECP_FIXED_POINT_OPTIM  1   /**< Enable fixed-point speed-up. */
-#endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */
-
-/* \} name SECTION: Module settings */
-
-#else  /* MBEDTLS_ECP_ALT */
-#include "ecp_alt.h"
-#endif /* MBEDTLS_ECP_ALT */
-
-/**
  * \brief    The ECP key-pair structure.
  *
  * A generic key-pair that may be used for ECDSA and fixed ECDH, for example.
@@ -321,9 +409,9 @@
  */
 typedef struct mbedtls_ecp_keypair
 {
-    mbedtls_ecp_group grp;      /*!<  Elliptic curve and base point     */
-    mbedtls_mpi d;              /*!<  our secret value                  */
-    mbedtls_ecp_point Q;        /*!<  our public value                  */
+    mbedtls_ecp_group MBEDTLS_PRIVATE(grp);      /*!<  Elliptic curve and base point     */
+    mbedtls_mpi MBEDTLS_PRIVATE(d);              /*!<  our secret value                  */
+    mbedtls_ecp_point MBEDTLS_PRIVATE(Q);        /*!<  our public value                  */
 }
 mbedtls_ecp_keypair;
 
@@ -407,10 +495,20 @@
 int mbedtls_ecp_restart_is_enabled( void );
 #endif /* MBEDTLS_ECP_RESTARTABLE */
 
+/*
+ * Get the type of a curve
+ */
+mbedtls_ecp_curve_type mbedtls_ecp_get_type( const mbedtls_ecp_group *grp );
+
 /**
  * \brief           This function retrieves the information defined in
- *                  mbedtls_ecp_curve_info() for all supported curves in order
- *                  of preference.
+ *                  mbedtls_ecp_curve_info() for all supported curves.
+ *
+ * \note            This function returns information about all curves
+ *                  supported by the library. Some curves may not be
+ *                  supported for all algorithms. Call mbedtls_ecdh_can_do()
+ *                  or mbedtls_ecdsa_can_do() to check if a curve is
+ *                  supported for ECDH or ECDSA.
  *
  * \return          A statically allocated array. The last entry is 0.
  */
@@ -421,6 +519,12 @@
  *                  identifiers of all supported curves in the order of
  *                  preference.
  *
+ * \note            This function returns information about all curves
+ *                  supported by the library. Some curves may not be
+ *                  supported for all algorithms. Call mbedtls_ecdh_can_do()
+ *                  or mbedtls_ecdsa_can_do() to check if a curve is
+ *                  supported for ECDH or ECDSA.
+ *
  * \return          A statically allocated array,
  *                  terminated with MBEDTLS_ECP_DP_NONE.
  */
@@ -472,7 +576,7 @@
  *
  * \note            After this function is called, domain parameters
  *                  for various ECP groups can be loaded through the
- *                  mbedtls_ecp_load() or mbedtls_ecp_tls_read_group()
+ *                  mbedtls_ecp_group_load() or mbedtls_ecp_tls_read_group()
  *                  functions.
  */
 void mbedtls_ecp_group_init( mbedtls_ecp_group *grp );
@@ -493,24 +597,37 @@
 
 /**
  * \brief           This function frees the components of an ECP group.
- * \param grp       The group to free.
+ *
+ * \param grp       The group to free. This may be \c NULL, in which
+ *                  case this function returns immediately. If it is not
+ *                  \c NULL, it must point to an initialized ECP group.
  */
 void mbedtls_ecp_group_free( mbedtls_ecp_group *grp );
 
 /**
  * \brief           This function frees the components of a key pair.
- * \param key       The key pair to free.
+ *
+ * \param key       The key pair to free. This may be \c NULL, in which
+ *                  case this function returns immediately. If it is not
+ *                  \c NULL, it must point to an initialized ECP key pair.
  */
 void mbedtls_ecp_keypair_free( mbedtls_ecp_keypair *key );
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)
 /**
- * \brief           Initialize a restart context
+ * \brief           Initialize a restart context.
+ *
+ * \param ctx       The restart context to initialize. This must
+ *                  not be \c NULL.
  */
 void mbedtls_ecp_restart_init( mbedtls_ecp_restart_ctx *ctx );
 
 /**
- * \brief           Free the components of a restart context
+ * \brief           Free the components of a restart context.
+ *
+ * \param ctx       The restart context to free. This may be \c NULL, in which
+ *                  case this function returns immediately. If it is not
+ *                  \c NULL, it must point to an initialized restart context.
  */
 void mbedtls_ecp_restart_free( mbedtls_ecp_restart_ctx *ctx );
 #endif /* MBEDTLS_ECP_RESTARTABLE */
@@ -519,11 +636,12 @@
  * \brief           This function copies the contents of point \p Q into
  *                  point \p P.
  *
- * \param P         The destination point.
- * \param Q         The source point.
+ * \param P         The destination point. This must be initialized.
+ * \param Q         The source point. This must be initialized.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          Another negative error code for other kinds of failure.
  */
 int mbedtls_ecp_copy( mbedtls_ecp_point *P, const mbedtls_ecp_point *Q );
 
@@ -531,31 +649,35 @@
  * \brief           This function copies the contents of group \p src into
  *                  group \p dst.
  *
- * \param dst       The destination group.
- * \param src       The source group.
+ * \param dst       The destination group. This must be initialized.
+ * \param src       The source group. This must be initialized.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst, const mbedtls_ecp_group *src );
+int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst,
+                            const mbedtls_ecp_group *src );
 
 /**
- * \brief           This function sets a point to zero.
+ * \brief           This function sets a point to the point at infinity.
  *
- * \param pt        The point to set.
+ * \param pt        The point to set. This must be initialized.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          Another negative error code on other kinds of failure.
  */
 int mbedtls_ecp_set_zero( mbedtls_ecp_point *pt );
 
 /**
- * \brief           This function checks if a point is zero.
+ * \brief           This function checks if a point is the point at infinity.
  *
- * \param pt        The point to test.
+ * \param pt        The point to test. This must be initialized.
  *
  * \return          \c 1 if the point is zero.
  * \return          \c 0 if the point is non-zero.
+ * \return          A negative error code on failure.
  */
 int mbedtls_ecp_is_zero( mbedtls_ecp_point *pt );
 
@@ -565,8 +687,8 @@
  * \note            This assumes that the points are normalized. Otherwise,
  *                  they may compare as "not equal" even if they are.
  *
- * \param P         The first point to compare.
- * \param Q         The second point to compare.
+ * \param P         The first point to compare. This must be initialized.
+ * \param Q         The second point to compare. This must be initialized.
  *
  * \return          \c 0 if the points are equal.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the points are not equal.
@@ -578,7 +700,7 @@
  * \brief           This function imports a non-zero point from two ASCII
  *                  strings.
  *
- * \param P         The destination point.
+ * \param P         The destination point. This must be initialized.
  * \param radix     The numeric base of the input.
  * \param x         The first affine coordinate, as a null-terminated string.
  * \param y         The second affine coordinate, as a null-terminated string.
@@ -593,19 +715,31 @@
  * \brief           This function exports a point into unsigned binary data.
  *
  * \param grp       The group to which the point should belong.
- * \param P         The point to export.
- * \param format    The point format. Should be an \c MBEDTLS_ECP_PF_XXX macro.
- * \param olen      The length of the output.
- * \param buf       The output buffer.
- * \param buflen    The length of the output buffer.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param P         The point to export. This must be initialized.
+ * \param format    The point format. This must be either
+ *                  #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED.
+ *                  (For groups without these formats, this parameter is
+ *                  ignored. But it still has to be either of the above
+ *                  values.)
+ * \param olen      The address at which to store the length of
+ *                  the output in Bytes. This must not be \c NULL.
+ * \param buf       The output buffer. This must be a writable buffer
+ *                  of length \p buflen Bytes.
+ * \param buflen    The length of the output buffer \p buf in Bytes.
  *
  * \return          \c 0 on success.
- * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA
- *                  or #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
+ * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output buffer
+ *                  is too small to hold the point.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format
+ *                  or the export for the given group is not implemented.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_point_write_binary( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *P,
-                            int format, size_t *olen,
-                            unsigned char *buf, size_t buflen );
+int mbedtls_ecp_point_write_binary( const mbedtls_ecp_group *grp,
+                                    const mbedtls_ecp_point *P,
+                                    int format, size_t *olen,
+                                    unsigned char *buf, size_t buflen );
 
 /**
  * \brief           This function imports a point from unsigned binary data.
@@ -615,132 +749,183 @@
  *                  for that.
  *
  * \param grp       The group to which the point should belong.
- * \param P         The point to import.
- * \param buf       The input buffer.
- * \param ilen      The length of the input.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param P         The destination context to import the point to.
+ *                  This must be initialized.
+ * \param buf       The input buffer. This must be a readable buffer
+ *                  of length \p ilen Bytes.
+ * \param ilen      The length of the input buffer \p buf in Bytes.
  *
  * \return          \c 0 on success.
- * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
+ * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
- * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format
- *                  is not implemented.
- *
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the import for the
+ *                  given group is not implemented.
  */
-int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P,
-                           const unsigned char *buf, size_t ilen );
+int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp,
+                                   mbedtls_ecp_point *P,
+                                   const unsigned char *buf, size_t ilen );
 
 /**
  * \brief           This function imports a point from a TLS ECPoint record.
  *
- * \note            On function return, \p buf is updated to point to immediately
+ * \note            On function return, \p *buf is updated to point immediately
  *                  after the ECPoint record.
  *
- * \param grp       The ECP group used.
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
  * \param pt        The destination point.
  * \param buf       The address of the pointer to the start of the input buffer.
  * \param len       The length of the buffer.
  *
  * \return          \c 0 on success.
- * \return          An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
+ * \return          An \c MBEDTLS_ERR_MPI_XXX error code on initialization
+ *                  failure.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
  */
-int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt,
-                        const unsigned char **buf, size_t len );
+int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp,
+                                mbedtls_ecp_point *pt,
+                                const unsigned char **buf, size_t len );
 
 /**
- * \brief           This function exports a point as a TLS ECPoint record.
+ * \brief           This function exports a point as a TLS ECPoint record
+ *                  defined in RFC 4492, Section 5.4.
  *
- * \param grp       The ECP group used.
- * \param pt        The point format to export to. The point format is an
- *                  \c MBEDTLS_ECP_PF_XXX constant.
- * \param format    The export format.
- * \param olen      The length of the data written.
- * \param buf       The buffer to write to.
- * \param blen      The length of the buffer.
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param pt        The point to be exported. This must be initialized.
+ * \param format    The point format to use. This must be either
+ *                  #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED.
+ * \param olen      The address at which to store the length in Bytes
+ *                  of the data written.
+ * \param buf       The target buffer. This must be a writable buffer of
+ *                  length \p blen Bytes.
+ * \param blen      The length of the target buffer \p buf in Bytes.
  *
  * \return          \c 0 on success.
- * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA or
- *                  #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
+ * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid.
+ * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the target buffer
+ *                  is too small to hold the exported point.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_tls_write_point( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt,
-                         int format, size_t *olen,
-                         unsigned char *buf, size_t blen );
+int mbedtls_ecp_tls_write_point( const mbedtls_ecp_group *grp,
+                                 const mbedtls_ecp_point *pt,
+                                 int format, size_t *olen,
+                                 unsigned char *buf, size_t blen );
 
 /**
- * \brief           This function sets a group using standardized domain parameters.
+ * \brief           This function sets up an ECP group context
+ *                  from a standardized set of domain parameters.
  *
  * \note            The index should be a value of the NamedCurve enum,
  *                  as defined in <em>RFC-4492: Elliptic Curve Cryptography
  *                  (ECC) Cipher Suites for Transport Layer Security (TLS)</em>,
  *                  usually in the form of an \c MBEDTLS_ECP_DP_XXX macro.
  *
- * \param grp       The destination group.
+ * \param grp       The group context to setup. This must be initialized.
  * \param id        The identifier of the domain parameter set to load.
  *
- * \return          \c 0 on success,
- * \return          An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
- * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE for unkownn groups.
-
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p id doesn't
+ *                  correspond to a known group.
+ * \return          Another negative error code on other kinds of failure.
  */
 int mbedtls_ecp_group_load( mbedtls_ecp_group *grp, mbedtls_ecp_group_id id );
 
 /**
- * \brief           This function sets a group from a TLS ECParameters record.
+ * \brief           This function sets up an ECP group context from a TLS
+ *                  ECParameters record as defined in RFC 4492, Section 5.4.
  *
- * \note            \p buf is updated to point right after the ECParameters record
- *                  on exit.
+ * \note            The read pointer \p buf is updated to point right after
+ *                  the ECParameters record on exit.
  *
- * \param grp       The destination group.
+ * \param grp       The group context to setup. This must be initialized.
  * \param buf       The address of the pointer to the start of the input buffer.
- * \param len       The length of the buffer.
+ * \param len       The length of the input buffer \c *buf in Bytes.
  *
  * \return          \c 0 on success.
- * \return          An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not
+ *                  recognized.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp, const unsigned char **buf, size_t len );
+int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp,
+                                const unsigned char **buf, size_t len );
 
 /**
- * \brief           This function writes the TLS ECParameters record for a group.
+ * \brief           This function extracts an elliptic curve group ID from a
+ *                  TLS ECParameters record as defined in RFC 4492, Section 5.4.
  *
- * \param grp       The ECP group used.
- * \param olen      The number of Bytes written.
- * \param buf       The buffer to write to.
- * \param blen      The length of the buffer.
+ * \note            The read pointer \p buf is updated to point right after
+ *                  the ECParameters record on exit.
+ *
+ * \param grp       The address at which to store the group id.
+ *                  This must not be \c NULL.
+ * \param buf       The address of the pointer to the start of the input buffer.
+ * \param len       The length of the input buffer \c *buf in Bytes.
  *
  * \return          \c 0 on success.
- * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
+ * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not
+ *                  recognized.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp, size_t *olen,
-                         unsigned char *buf, size_t blen );
+int mbedtls_ecp_tls_read_group_id( mbedtls_ecp_group_id *grp,
+                                   const unsigned char **buf,
+                                   size_t len );
+/**
+ * \brief           This function exports an elliptic curve as a TLS
+ *                  ECParameters record as defined in RFC 4492, Section 5.4.
+ *
+ * \param grp       The ECP group to be exported.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param olen      The address at which to store the number of Bytes written.
+ *                  This must not be \c NULL.
+ * \param buf       The buffer to write to. This must be a writable buffer
+ *                  of length \p blen Bytes.
+ * \param blen      The length of the output buffer \p buf in Bytes.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output
+ *                  buffer is too small to hold the exported group.
+ * \return          Another negative error code on other kinds of failure.
+ */
+int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp,
+                                 size_t *olen,
+                                 unsigned char *buf, size_t blen );
 
 /**
- * \brief           This function performs multiplication of a point by
- *                  an integer: \p R = \p m * \p P.
+ * \brief           This function performs a scalar multiplication of a point
+ *                  by an integer: \p R = \p m * \p P.
  *
  *                  It is not thread-safe to use same group in multiple threads.
  *
  * \note            To prevent timing attacks, this function
  *                  executes the exact same sequence of base-field
  *                  operations for any valid \p m. It avoids any if-branch or
- *                  array index depending on the value of \p m.
+ *                  array index depending on the value of \p m. If also uses
+ *                  \p f_rng to randomize some intermediate results.
  *
- * \note            If \p f_rng is not NULL, it is used to randomize
- *                  intermediate results to prevent potential timing attacks
- *                  targeting these results. We recommend always providing
- *                  a non-NULL \p f_rng. The overhead is negligible.
- *
- * \param grp       The ECP group.
- * \param R         The destination point.
- * \param m         The integer by which to multiply.
- * \param P         The point to multiply.
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param R         The point in which to store the result of the calculation.
+ *                  This must be initialized.
+ * \param m         The integer by which to multiply. This must be initialized.
+ * \param P         The point to multiply. This must be initialized.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may be \c
+ *                  NULL if \p f_rng doesn't need a context.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_ECP_INVALID_KEY if \p m is not a valid private
  *                  key, or \p P is not a valid public key.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          Another negative error code on other kinds of failure.
  */
 int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
              const mbedtls_mpi *m, const mbedtls_ecp_point *P,
@@ -756,12 +941,16 @@
  *                  it can return early and restart according to the limit set
  *                  with \c mbedtls_ecp_set_max_ops() to reduce blocking.
  *
- * \param grp       The ECP group.
- * \param R         The destination point.
- * \param m         The integer by which to multiply.
- * \param P         The point to multiply.
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param R         The point in which to store the result of the calculation.
+ *                  This must be initialized.
+ * \param m         The integer by which to multiply. This must be initialized.
+ * \param P         The point to multiply. This must be initialized.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may be \c
+ *                  NULL if \p f_rng doesn't need a context.
  * \param rs_ctx    The restart context (NULL disables restart).
  *
  * \return          \c 0 on success.
@@ -770,12 +959,14 @@
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
  * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
  *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ * \return          Another negative error code on other kinds of failure.
  */
 int mbedtls_ecp_mul_restartable( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
              const mbedtls_mpi *m, const mbedtls_ecp_point *P,
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
              mbedtls_ecp_restart_ctx *rs_ctx );
 
+#if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED)
 /**
  * \brief           This function performs multiplication and addition of two
  *                  points by integers: \p R = \p m * \p P + \p n * \p Q
@@ -785,18 +976,31 @@
  * \note            In contrast to mbedtls_ecp_mul(), this function does not
  *                  guarantee a constant execution flow and timing.
  *
- * \param grp       The ECP group.
- * \param R         The destination point.
+ * \note            This function is only defined for short Weierstrass curves.
+ *                  It may not be included in builds without any short
+ *                  Weierstrass curve.
+ *
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param R         The point in which to store the result of the calculation.
+ *                  This must be initialized.
  * \param m         The integer by which to multiply \p P.
- * \param P         The point to multiply by \p m.
+ *                  This must be initialized.
+ * \param P         The point to multiply by \p m. This must be initialized.
  * \param n         The integer by which to multiply \p Q.
+ *                  This must be initialized.
  * \param Q         The point to be multiplied by \p n.
+ *                  This must be initialized.
  *
  * \return          \c 0 on success.
  * \return          #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not
  *                  valid private keys, or \p P or \p Q are not valid public
  *                  keys.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p grp does not
+ *                  designate a short Weierstrass curve.
+ * \return          Another negative error code on other kinds of failure.
  */
 int mbedtls_ecp_muladd( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
              const mbedtls_mpi *m, const mbedtls_ecp_point *P,
@@ -813,12 +1017,22 @@
  *                  but it can return early and restart according to the limit
  *                  set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
  *
- * \param grp       The ECP group.
- * \param R         The destination point.
+ * \note            This function is only defined for short Weierstrass curves.
+ *                  It may not be included in builds without any short
+ *                  Weierstrass curve.
+ *
+ * \param grp       The ECP group to use.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param R         The point in which to store the result of the calculation.
+ *                  This must be initialized.
  * \param m         The integer by which to multiply \p P.
- * \param P         The point to multiply by \p m.
+ *                  This must be initialized.
+ * \param P         The point to multiply by \p m. This must be initialized.
  * \param n         The integer by which to multiply \p Q.
+ *                  This must be initialized.
  * \param Q         The point to be multiplied by \p n.
+ *                  This must be initialized.
  * \param rs_ctx    The restart context (NULL disables restart).
  *
  * \return          \c 0 on success.
@@ -826,14 +1040,18 @@
  *                  valid private keys, or \p P or \p Q are not valid public
  *                  keys.
  * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p grp does not
+ *                  designate a short Weierstrass curve.
  * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
  *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
+ * \return          Another negative error code on other kinds of failure.
  */
 int mbedtls_ecp_muladd_restartable(
              mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
              const mbedtls_mpi *m, const mbedtls_ecp_point *P,
              const mbedtls_mpi *n, const mbedtls_ecp_point *Q,
              mbedtls_ecp_restart_ctx *rs_ctx );
+#endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */
 
 /**
  * \brief           This function checks that a point is a valid public key
@@ -852,38 +1070,51 @@
  *                  structures, such as ::mbedtls_ecdh_context or
  *                  ::mbedtls_ecdsa_context.
  *
- * \param grp       The curve the point should lie on.
- * \param pt        The point to check.
+ * \param grp       The ECP group the point should belong to.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param pt        The point to check. This must be initialized.
  *
  * \return          \c 0 if the point is a valid public key.
- * \return          #MBEDTLS_ERR_ECP_INVALID_KEY on failure.
+ * \return          #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not
+ *                  a valid public key for the given curve.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt );
+int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp,
+                              const mbedtls_ecp_point *pt );
 
 /**
- * \brief           This function checks that an \p mbedtls_mpi is a valid private
- *                  key for this curve.
+ * \brief           This function checks that an \p mbedtls_mpi is a
+ *                  valid private key for this curve.
  *
  * \note            This function uses bare components rather than an
  *                  ::mbedtls_ecp_keypair structure to ease use with other
  *                  structures, such as ::mbedtls_ecdh_context or
  *                  ::mbedtls_ecdsa_context.
  *
- * \param grp       The group used.
- * \param d         The integer to check.
+ * \param grp       The ECP group the private key should belong to.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param d         The integer to check. This must be initialized.
  *
  * \return          \c 0 if the point is a valid private key.
- * \return          #MBEDTLS_ERR_ECP_INVALID_KEY on failure.
+ * \return          #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not a valid
+ *                  private key for the given curve.
+ * \return          Another negative error code on other kinds of failure.
  */
-int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp, const mbedtls_mpi *d );
+int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp,
+                               const mbedtls_mpi *d );
 
 /**
  * \brief           This function generates a private key.
  *
- * \param grp       The ECP group.
- * \param d         The destination MPI (secret part).
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG parameter.
+ * \param grp       The ECP group to generate a private key for.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param d         The destination MPI (secret part). This must be initialized.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG parameter to be passed to \p f_rng. This may be
+ *                  \c NULL if \p f_rng doesn't need a context argument.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
@@ -903,22 +1134,29 @@
  *                  structures, such as ::mbedtls_ecdh_context or
  *                  ::mbedtls_ecdsa_context.
  *
- * \param grp       The ECP group.
- * \param G         The chosen base point.
+ * \param grp       The ECP group to generate a key pair for.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
+ * \param G         The base point to use. This must be initialized
+ *                  and belong to \p grp. It replaces the default base
+ *                  point \c grp->G used by mbedtls_ecp_gen_keypair().
  * \param d         The destination MPI (secret part).
+ *                  This must be initialized.
  * \param Q         The destination point (public part).
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ *                  This must be initialized.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may
+ *                  be \c NULL if \p f_rng doesn't need a context argument.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
  *                  on failure.
  */
 int mbedtls_ecp_gen_keypair_base( mbedtls_ecp_group *grp,
-                     const mbedtls_ecp_point *G,
-                     mbedtls_mpi *d, mbedtls_ecp_point *Q,
-                     int (*f_rng)(void *, unsigned char *, size_t),
-                     void *p_rng );
+                                  const mbedtls_ecp_point *G,
+                                  mbedtls_mpi *d, mbedtls_ecp_point *Q,
+                                  int (*f_rng)(void *, unsigned char *, size_t),
+                                  void *p_rng );
 
 /**
  * \brief           This function generates an ECP keypair.
@@ -928,34 +1166,82 @@
  *                  structures, such as ::mbedtls_ecdh_context or
  *                  ::mbedtls_ecdsa_context.
  *
- * \param grp       The ECP group.
+ * \param grp       The ECP group to generate a key pair for.
+ *                  This must be initialized and have group parameters
+ *                  set, for example through mbedtls_ecp_group_load().
  * \param d         The destination MPI (secret part).
+ *                  This must be initialized.
  * \param Q         The destination point (public part).
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ *                  This must be initialized.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may
+ *                  be \c NULL if \p f_rng doesn't need a context argument.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
  *                  on failure.
  */
-int mbedtls_ecp_gen_keypair( mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q,
-                     int (*f_rng)(void *, unsigned char *, size_t),
-                     void *p_rng );
+int mbedtls_ecp_gen_keypair( mbedtls_ecp_group *grp, mbedtls_mpi *d,
+                             mbedtls_ecp_point *Q,
+                             int (*f_rng)(void *, unsigned char *, size_t),
+                             void *p_rng );
 
 /**
  * \brief           This function generates an ECP key.
  *
  * \param grp_id    The ECP group identifier.
- * \param key       The destination key.
- * \param f_rng     The RNG function.
- * \param p_rng     The RNG context.
+ * \param key       The destination key. This must be initialized.
+ * \param f_rng     The RNG function to use. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may
+ *                  be \c NULL if \p f_rng doesn't need a context argument.
  *
  * \return          \c 0 on success.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
  *                  on failure.
  */
 int mbedtls_ecp_gen_key( mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key,
-                int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng );
+
+/**
+ * \brief           This function reads an elliptic curve private key.
+ *
+ * \param grp_id    The ECP group identifier.
+ * \param key       The destination key.
+ * \param buf       The buffer containing the binary representation of the
+ *                  key. (Big endian integer for Weierstrass curves, byte
+ *                  string for Montgomery curves.)
+ * \param buflen    The length of the buffer in bytes.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_ECP_INVALID_KEY error if the key is
+ *                  invalid.
+ * \return          #MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the operation for
+ *                  the group is not implemented.
+ * \return          Another negative error code on different kinds of failure.
+ */
+int mbedtls_ecp_read_key( mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key,
+                          const unsigned char *buf, size_t buflen );
+
+/**
+ * \brief           This function exports an elliptic curve private key.
+ *
+ * \param key       The private key.
+ * \param buf       The output buffer for containing the binary representation
+ *                  of the key. (Big endian integer for Weierstrass curves, byte
+ *                  string for Montgomery curves.)
+ * \param buflen    The total length of the buffer in bytes.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the \p key
+                    representation is larger than the available space in \p buf.
+ * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the operation for
+ *                  the group is not implemented.
+ * \return          Another negative error code on different kinds of failure.
+ */
+int mbedtls_ecp_write_key( mbedtls_ecp_keypair *key,
+                           unsigned char *buf, size_t buflen );
 
 /**
  * \brief           This function checks that the keypair objects
@@ -963,16 +1249,23 @@
  *                  same public point, and that the private key in
  *                  \p prv is consistent with the public key.
  *
- * \param pub       The keypair structure holding the public key.
- *                  If it contains a private key, that part is ignored.
+ * \param pub       The keypair structure holding the public key. This
+ *                  must be initialized. If it contains a private key, that
+ *                  part is ignored.
  * \param prv       The keypair structure holding the full keypair.
+ *                  This must be initialized.
+ * \param f_rng     The RNG function. This must not be \c NULL.
+ * \param p_rng     The RNG context to be passed to \p f_rng. This may be \c
+ *                  NULL if \p f_rng doesn't need a context.
  *
  * \return          \c 0 on success, meaning that the keys are valid and match.
  * \return          #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the keys are invalid or do not match.
  * \return          An \c MBEDTLS_ERR_ECP_XXX or an \c MBEDTLS_ERR_MPI_XXX
  *                  error code on calculation failure.
  */
-int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv );
+int mbedtls_ecp_check_pub_priv(
+        const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv,
+        int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 #if defined(MBEDTLS_SELF_TEST)
 
diff --git a/ext/mbedtls-asn1/include/mbedtls/error.h b/ext/mbedtls-asn1/include/mbedtls/error.h
new file mode 100644
index 0000000..9a8690d
--- /dev/null
+++ b/ext/mbedtls-asn1/include/mbedtls/error.h
@@ -0,0 +1,210 @@
+/**
+ * \file error.h
+ *
+ * \brief Error to string translation
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+#ifndef MBEDTLS_ERROR_H
+#define MBEDTLS_ERROR_H
+
+#include "mbedtls/build_info.h"
+
+#include <stddef.h>
+
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
+#define inline __inline
+#endif
+
+/**
+ * Error code layout.
+ *
+ * Currently we try to keep all error codes within the negative space of 16
+ * bits signed integers to support all platforms (-0x0001 - -0x7FFF). In
+ * addition we'd like to give two layers of information on the error if
+ * possible.
+ *
+ * For that purpose the error codes are segmented in the following manner:
+ *
+ * 16 bit error code bit-segmentation
+ *
+ * 1 bit  - Unused (sign bit)
+ * 3 bits - High level module ID
+ * 5 bits - Module-dependent error code
+ * 7 bits - Low level module errors
+ *
+ * For historical reasons, low-level error codes are divided in even and odd,
+ * even codes were assigned first, and -1 is reserved for other errors.
+ *
+ * Low-level module errors (0x0002-0x007E, 0x0001-0x007F)
+ *
+ * Module   Nr  Codes assigned
+ * ERROR     2  0x006E          0x0001
+ * MPI       7  0x0002-0x0010
+ * GCM       3  0x0012-0x0014   0x0013-0x0013
+ * THREADING 3  0x001A-0x001E
+ * AES       5  0x0020-0x0022   0x0021-0x0025
+ * CAMELLIA  3  0x0024-0x0026   0x0027-0x0027
+ * BASE64    2  0x002A-0x002C
+ * OID       1  0x002E-0x002E   0x000B-0x000B
+ * PADLOCK   1  0x0030-0x0030
+ * DES       2  0x0032-0x0032   0x0033-0x0033
+ * CTR_DBRG  4  0x0034-0x003A
+ * ENTROPY   3  0x003C-0x0040   0x003D-0x003F
+ * NET      13  0x0042-0x0052   0x0043-0x0049
+ * ARIA      4  0x0058-0x005E
+ * ASN1      7  0x0060-0x006C
+ * CMAC      1  0x007A-0x007A
+ * PBKDF2    1  0x007C-0x007C
+ * HMAC_DRBG 4                  0x0003-0x0009
+ * CCM       3                  0x000D-0x0011
+ * MD5       1                  0x002F-0x002F
+ * RIPEMD160 1                  0x0031-0x0031
+ * SHA1      1                  0x0035-0x0035 0x0073-0x0073
+ * SHA256    1                  0x0037-0x0037 0x0074-0x0074
+ * SHA512    1                  0x0039-0x0039 0x0075-0x0075
+ * CHACHA20  3                  0x0051-0x0055
+ * POLY1305  3                  0x0057-0x005B
+ * CHACHAPOLY 2 0x0054-0x0056
+ * PLATFORM  2  0x0070-0x0072
+ *
+ * High-level module nr (3 bits - 0x0...-0x7...)
+ * Name      ID  Nr of Errors
+ * PEM       1   9
+ * PKCS#12   1   4 (Started from top)
+ * X509      2   20
+ * PKCS5     2   4 (Started from top)
+ * DHM       3   11
+ * PK        3   15 (Started from top)
+ * RSA       4   11
+ * ECP       4   10 (Started from top)
+ * MD        5   5
+ * HKDF      5   1 (Started from top)
+ * SSL       5   2 (Started from 0x5F00)
+ * CIPHER    6   8 (Started from 0x6080)
+ * SSL       6   22 (Started from top, plus 0x6000)
+ * SSL       7   20 (Started from 0x7000, gaps at
+ *                   0x7380, 0x7900-0x7980, 0x7A80-0x7E80)
+ *
+ * Module dependent error code (5 bits 0x.00.-0x.F8.)
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define MBEDTLS_ERR_ERROR_GENERIC_ERROR       -0x0001  /**< Generic error */
+#define MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED -0x006E  /**< This is a bug in the library */
+
+#define MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED     -0x0070 /**< Hardware accelerator failed */
+#define MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED -0x0072 /**< The requested feature is not supported by the platform */
+
+/**
+ * \brief Combines a high-level and low-level error code together.
+ *
+ *        Wrapper macro for mbedtls_error_add(). See that function for
+ *        more details.
+ */
+#define MBEDTLS_ERROR_ADD( high, low ) \
+        mbedtls_error_add( high, low, __FILE__, __LINE__ )
+
+#if defined(MBEDTLS_TEST_HOOKS)
+/**
+ * \brief Testing hook called before adding/combining two error codes together.
+ *        Only used when invasive testing is enabled via MBEDTLS_TEST_HOOKS.
+ */
+extern void (*mbedtls_test_hook_error_add)( int, int, const char *, int );
+#endif
+
+/**
+ * \brief Combines a high-level and low-level error code together.
+ *
+ *        This function can be called directly however it is usually
+ *        called via the #MBEDTLS_ERROR_ADD macro.
+ *
+ *        While a value of zero is not a negative error code, it is still an
+ *        error code (that denotes success) and can be combined with both a
+ *        negative error code or another value of zero.
+ *
+ * \note  When invasive testing is enabled via #MBEDTLS_TEST_HOOKS, also try to
+ *        call \link mbedtls_test_hook_error_add \endlink.
+ *
+ * \param high      high-level error code. See error.h for more details.
+ * \param low       low-level error code. See error.h for more details.
+ * \param file      file where this error code addition occurred.
+ * \param line      line where this error code addition occurred.
+ */
+static inline int mbedtls_error_add( int high, int low,
+                                     const char *file, int line )
+{
+#if defined(MBEDTLS_TEST_HOOKS)
+    if( *mbedtls_test_hook_error_add != NULL )
+        ( *mbedtls_test_hook_error_add )( high, low, file, line );
+#endif
+    (void)file;
+    (void)line;
+
+    return( high + low );
+}
+
+/**
+ * \brief Translate a mbed TLS error code into a string representation,
+ *        Result is truncated if necessary and always includes a terminating
+ *        null byte.
+ *
+ * \param errnum    error code
+ * \param buffer    buffer to place representation in
+ * \param buflen    length of the buffer
+ */
+void mbedtls_strerror( int errnum, char *buffer, size_t buflen );
+
+/**
+ * \brief Translate the high-level part of an Mbed TLS error code into a string
+ *        representation.
+ *
+ * This function returns a const pointer to an un-modifiable string. The caller
+ * must not try to modify the string. It is intended to be used mostly for
+ * logging purposes.
+ *
+ * \param error_code    error code
+ *
+ * \return The string representation of the error code, or \c NULL if the error
+ *         code is unknown.
+ */
+const char * mbedtls_high_level_strerr( int error_code );
+
+/**
+ * \brief Translate the low-level part of an Mbed TLS error code into a string
+ *        representation.
+ *
+ * This function returns a const pointer to an un-modifiable string. The caller
+ * must not try to modify the string. It is intended to be used mostly for
+ * logging purposes.
+ *
+ * \param error_code    error code
+ *
+ * \return The string representation of the error code, or \c NULL if the error
+ *         code is unknown.
+ */
+const char * mbedtls_low_level_strerr( int error_code );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* error.h */
diff --git a/ext/mbedtls-asn1/include/mbedtls/config.h b/ext/mbedtls-asn1/include/mbedtls/mbedtls_config.h
similarity index 100%
rename from ext/mbedtls-asn1/include/mbedtls/config.h
rename to ext/mbedtls-asn1/include/mbedtls/mbedtls_config.h
diff --git a/ext/mbedtls-asn1/include/mbedtls/md.h b/ext/mbedtls-asn1/include/mbedtls/md.h
index 8bcf766..1170bc1 100644
--- a/ext/mbedtls-asn1/include/mbedtls/md.h
+++ b/ext/mbedtls-asn1/include/mbedtls/md.h
@@ -6,7 +6,7 @@
  * \author Adriaan de Jong <dejong@fox-it.com>
  */
 /*
- *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -20,29 +20,21 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of Mbed TLS (https://tls.mbed.org)
  */
 
 #ifndef MBEDTLS_MD_H
 #define MBEDTLS_MD_H
+#include "mbedtls/private_access.h"
 
 #include <stddef.h>
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
 #define MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE                -0x5080  /**< The selected feature is not available. */
 #define MBEDTLS_ERR_MD_BAD_INPUT_DATA                     -0x5100  /**< Bad input parameters to function. */
 #define MBEDTLS_ERR_MD_ALLOC_FAILED                       -0x5180  /**< Failed to allocate memory. */
 #define MBEDTLS_ERR_MD_FILE_IO_ERROR                      -0x5200  /**< Opening or reading of file failed. */
 
-/* MBEDTLS_ERR_MD_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_MD_HW_ACCEL_FAILED                    -0x5280  /**< MD hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -50,15 +42,13 @@
 /**
  * \brief     Supported message digests.
  *
- * \warning   MD2, MD4, MD5 and SHA-1 are considered weak message digests and
+ * \warning   MD5 and SHA-1 are considered weak message digests and
  *            their use constitutes a security risk. We recommend considering
  *            stronger message digests instead.
  *
  */
 typedef enum {
     MBEDTLS_MD_NONE=0,    /**< None. */
-    MBEDTLS_MD_MD2,       /**< The MD2 message digest. */
-    MBEDTLS_MD_MD4,       /**< The MD4 message digest. */
     MBEDTLS_MD_MD5,       /**< The MD5 message digest. */
     MBEDTLS_MD_SHA1,      /**< The SHA-1 message digest. */
     MBEDTLS_MD_SHA224,    /**< The SHA-224 message digest. */
@@ -74,9 +64,22 @@
 #define MBEDTLS_MD_MAX_SIZE         32  /* longest known is SHA256 or less */
 #endif
 
+#if defined(MBEDTLS_SHA512_C)
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         128
+#else
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         64
+#endif
+
 /**
- * Opaque struct defined in md_internal.h.
+ * Opaque struct.
+ *
+ * Constructed using either #mbedtls_md_info_from_string or
+ * #mbedtls_md_info_from_type.
+ *
+ * Fields can be accessed with #mbedtls_md_get_size,
+ * #mbedtls_md_get_type and #mbedtls_md_get_name.
  */
+/* Defined internally in library/md_wrap.h. */
 typedef struct mbedtls_md_info_t mbedtls_md_info_t;
 
 /**
@@ -85,19 +88,21 @@
 typedef struct mbedtls_md_context_t
 {
     /** Information about the associated message digest. */
-    const mbedtls_md_info_t *md_info;
+    const mbedtls_md_info_t *MBEDTLS_PRIVATE(md_info);
 
     /** The digest-specific context. */
-    void *md_ctx;
+    void *MBEDTLS_PRIVATE(md_ctx);
 
     /** The HMAC part of the context. */
-    void *hmac_ctx;
+    void *MBEDTLS_PRIVATE(hmac_ctx);
 } mbedtls_md_context_t;
 
 /**
  * \brief           This function returns the list of digests supported by the
  *                  generic digest module.
  *
+ * \note            The list starts with the strongest available hashes.
+ *
  * \return          A statically allocated array of digests. Each element
  *                  in the returned list is an integer belonging to the
  *                  message-digest enumeration #mbedtls_md_type_t.
@@ -152,33 +157,6 @@
  */
 void mbedtls_md_free( mbedtls_md_context_t *ctx );
 
-#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
-#if defined(MBEDTLS_DEPRECATED_WARNING)
-#define MBEDTLS_DEPRECATED    __attribute__((deprecated))
-#else
-#define MBEDTLS_DEPRECATED
-#endif
-/**
- * \brief           This function selects the message digest algorithm to use,
- *                  and allocates internal structures.
- *
- *                  It should be called after mbedtls_md_init() or mbedtls_md_free().
- *                  Makes it necessary to call mbedtls_md_free() later.
- *
- * \deprecated      Superseded by mbedtls_md_setup() in 2.0.0
- *
- * \param ctx       The context to set up.
- * \param md_info   The information structure of the message-digest algorithm
- *                  to use.
- *
- * \return          \c 0 on success.
- * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
- *                  failure.
- * \return          #MBEDTLS_ERR_MD_ALLOC_FAILED on memory-allocation failure.
- */
-int mbedtls_md_init_ctx( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info ) MBEDTLS_DEPRECATED;
-#undef MBEDTLS_DEPRECATED
-#endif /* MBEDTLS_DEPRECATED_REMOVED */
 
 /**
  * \brief           This function selects the message digest algorithm to use,
diff --git a/ext/mbedtls-asn1/include/mbedtls/oid.h b/ext/mbedtls-asn1/include/mbedtls/oid.h
index fcecdaf..9e68e91 100644
--- a/ext/mbedtls-asn1/include/mbedtls/oid.h
+++ b/ext/mbedtls-asn1/include/mbedtls/oid.h
@@ -2,8 +2,9 @@
  * \file oid.h
  *
  * \brief Object Identifier (OID) database
- *
- *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -17,38 +18,51 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 #ifndef MBEDTLS_OID_H
 #define MBEDTLS_OID_H
+#include "mbedtls/private_access.h"
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
-#include "asn1.h"
-#include "pk.h"
+#include "mbedtls/asn1.h"
+#include "mbedtls/pk.h"
 
 #include <stddef.h>
 
 #if defined(MBEDTLS_CIPHER_C)
-#include "cipher.h"
+#include "mbedtls/cipher.h"
 #endif
 
 #if defined(MBEDTLS_MD_C)
-#include "md.h"
-#endif
-
-#if defined(MBEDTLS_X509_USE_C) || defined(MBEDTLS_X509_CREATE_C)
-#include "x509.h"
+#include "mbedtls/md.h"
 #endif
 
 #define MBEDTLS_ERR_OID_NOT_FOUND                         -0x002E  /**< OID is not found. */
 #define MBEDTLS_ERR_OID_BUF_TOO_SMALL                     -0x000B  /**< output buffer is too small */
 
+/* This is for the benefit of X.509, but defined here in order to avoid
+ * having a "backwards" include of x.509.h here */
+/*
+ * X.509 extension types (internal, arbitrary values for bitsets)
+ */
+#define MBEDTLS_OID_X509_EXT_AUTHORITY_KEY_IDENTIFIER    (1 << 0)
+#define MBEDTLS_OID_X509_EXT_SUBJECT_KEY_IDENTIFIER      (1 << 1)
+#define MBEDTLS_OID_X509_EXT_KEY_USAGE                   (1 << 2)
+#define MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES        (1 << 3)
+#define MBEDTLS_OID_X509_EXT_POLICY_MAPPINGS             (1 << 4)
+#define MBEDTLS_OID_X509_EXT_SUBJECT_ALT_NAME            (1 << 5)
+#define MBEDTLS_OID_X509_EXT_ISSUER_ALT_NAME             (1 << 6)
+#define MBEDTLS_OID_X509_EXT_SUBJECT_DIRECTORY_ATTRS     (1 << 7)
+#define MBEDTLS_OID_X509_EXT_BASIC_CONSTRAINTS           (1 << 8)
+#define MBEDTLS_OID_X509_EXT_NAME_CONSTRAINTS            (1 << 9)
+#define MBEDTLS_OID_X509_EXT_POLICY_CONSTRAINTS          (1 << 10)
+#define MBEDTLS_OID_X509_EXT_EXTENDED_KEY_USAGE          (1 << 11)
+#define MBEDTLS_OID_X509_EXT_CRL_DISTRIBUTION_POINTS     (1 << 12)
+#define MBEDTLS_OID_X509_EXT_INIHIBIT_ANYPOLICY          (1 << 13)
+#define MBEDTLS_OID_X509_EXT_FRESHEST_CRL                (1 << 14)
+#define MBEDTLS_OID_X509_EXT_NS_CERT_TYPE                (1 << 16)
+
 /*
  * Top level OID tuples
  */
@@ -96,12 +110,15 @@
 /* ISO arc for standard certificate and CRL extensions */
 #define MBEDTLS_OID_ID_CE                       MBEDTLS_OID_ISO_CCITT_DS "\x1D" /**< id-ce OBJECT IDENTIFIER  ::=  {joint-iso-ccitt(2) ds(5) 29} */
 
+#define MBEDTLS_OID_NIST_ALG                    MBEDTLS_OID_GOV "\x03\x04" /** { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) */
+
 /**
  * Private Internet Extensions
  * { iso(1) identified-organization(3) dod(6) internet(1)
  *                      security(5) mechanisms(5) pkix(7) }
  */
-#define MBEDTLS_OID_PKIX                        MBEDTLS_OID_ISO_IDENTIFIED_ORG MBEDTLS_OID_ORG_DOD "\x01\x05\x05\x07"
+#define MBEDTLS_OID_INTERNET                    MBEDTLS_OID_ISO_IDENTIFIED_ORG MBEDTLS_OID_ORG_DOD "\x01"
+#define MBEDTLS_OID_PKIX                        MBEDTLS_OID_INTERNET "\x05\x05\x07"
 
 /*
  * Arc for standard naming attributes
@@ -125,6 +142,7 @@
 #define MBEDTLS_OID_AT_DN_QUALIFIER             MBEDTLS_OID_AT "\x2E" /**< id-at-dnQualifier AttributeType:= {id-at 46} */
 #define MBEDTLS_OID_AT_PSEUDONYM                MBEDTLS_OID_AT "\x41" /**< id-at-pseudonym AttributeType:= {id-at 65} */
 
+#define MBEDTLS_OID_UID                         "\x09\x92\x26\x89\x93\xF2\x2C\x64\x01\x01" /** id-domainComponent AttributeType:= {itu-t(0) data(9) pss(2342) ucl(19200300) pilot(100) pilotAttributeType(1) uid(1)} */
 #define MBEDTLS_OID_DOMAIN_COMPONENT            "\x09\x92\x26\x89\x93\xF2\x2C\x64\x01\x19" /** id-domainComponent AttributeType:= {itu-t(0) data(9) pss(2342) ucl(19200300) pilot(100) pilotAttributeType(1) domainComponent(25)} */
 
 /*
@@ -147,6 +165,11 @@
 #define MBEDTLS_OID_FRESHEST_CRL                MBEDTLS_OID_ID_CE "\x2E" /**< id-ce-freshestCRL OBJECT IDENTIFIER ::=  { id-ce 46 } */
 
 /*
+ * Certificate policies
+ */
+#define MBEDTLS_OID_ANY_POLICY              MBEDTLS_OID_CERTIFICATE_POLICIES "\x00" /**< anyPolicy OBJECT IDENTIFIER ::= { id-ce-certificatePolicies 0 } */
+
+/*
  * Netscape certificate extensions
  */
 #define MBEDTLS_OID_NS_CERT                 MBEDTLS_OID_NETSCAPE "\x01"
@@ -180,6 +203,16 @@
 #define MBEDTLS_OID_TIME_STAMPING               MBEDTLS_OID_KP "\x08" /**< id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 } */
 #define MBEDTLS_OID_OCSP_SIGNING                MBEDTLS_OID_KP "\x09" /**< id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 } */
 
+/**
+ * Wi-SUN Alliance Field Area Network
+ * { iso(1) identified-organization(3) dod(6) internet(1)
+ *                      private(4) enterprise(1) WiSUN(45605) FieldAreaNetwork(1) }
+ */
+#define MBEDTLS_OID_WISUN_FAN                   MBEDTLS_OID_INTERNET "\x04\x01\x82\xe4\x25\x01"
+
+#define MBEDTLS_OID_ON                          MBEDTLS_OID_PKIX "\x08" /**< id-on OBJECT IDENTIFIER ::= { id-pkix 8 } */
+#define MBEDTLS_OID_ON_HW_MODULE_NAME           MBEDTLS_OID_ON "\x04" /**< id-on-hardwareModuleName OBJECT IDENTIFIER ::= { id-on 4 } */
+
 /*
  * PKCS definition OIDs
  */
@@ -194,8 +227,6 @@
  * PKCS#1 OIDs
  */
 #define MBEDTLS_OID_PKCS1_RSA           MBEDTLS_OID_PKCS1 "\x01" /**< rsaEncryption OBJECT IDENTIFIER ::= { pkcs-1 1 } */
-#define MBEDTLS_OID_PKCS1_MD2           MBEDTLS_OID_PKCS1 "\x02" /**< md2WithRSAEncryption ::= { pkcs-1 2 } */
-#define MBEDTLS_OID_PKCS1_MD4           MBEDTLS_OID_PKCS1 "\x03" /**< md4WithRSAEncryption ::= { pkcs-1 3 } */
 #define MBEDTLS_OID_PKCS1_MD5           MBEDTLS_OID_PKCS1 "\x04" /**< md5WithRSAEncryption ::= { pkcs-1 4 } */
 #define MBEDTLS_OID_PKCS1_SHA1          MBEDTLS_OID_PKCS1 "\x05" /**< sha1WithRSAEncryption ::= { pkcs-1 5 } */
 #define MBEDTLS_OID_PKCS1_SHA224        MBEDTLS_OID_PKCS1 "\x0e" /**< sha224WithRSAEncryption ::= { pkcs-1 14 } */
@@ -214,26 +245,47 @@
 /*
  * Digest algorithms
  */
-#define MBEDTLS_OID_DIGEST_ALG_MD2              MBEDTLS_OID_RSA_COMPANY "\x02\x02" /**< id-mbedtls_md2 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 2 } */
-#define MBEDTLS_OID_DIGEST_ALG_MD4              MBEDTLS_OID_RSA_COMPANY "\x02\x04" /**< id-mbedtls_md4 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 4 } */
 #define MBEDTLS_OID_DIGEST_ALG_MD5              MBEDTLS_OID_RSA_COMPANY "\x02\x05" /**< id-mbedtls_md5 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 5 } */
 #define MBEDTLS_OID_DIGEST_ALG_SHA1             MBEDTLS_OID_ISO_IDENTIFIED_ORG MBEDTLS_OID_OIW_SECSIG_SHA1 /**< id-mbedtls_sha1 OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) oiw(14) secsig(3) algorithms(2) 26 } */
-#define MBEDTLS_OID_DIGEST_ALG_SHA224           MBEDTLS_OID_GOV "\x03\x04\x02\x04" /**< id-sha224 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 4 } */
-#define MBEDTLS_OID_DIGEST_ALG_SHA256           MBEDTLS_OID_GOV "\x03\x04\x02\x01" /**< id-mbedtls_sha256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 1 } */
+#define MBEDTLS_OID_DIGEST_ALG_SHA224           MBEDTLS_OID_NIST_ALG "\x02\x04" /**< id-sha224 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 4 } */
+#define MBEDTLS_OID_DIGEST_ALG_SHA256           MBEDTLS_OID_NIST_ALG "\x02\x01" /**< id-mbedtls_sha256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 1 } */
 
-#define MBEDTLS_OID_DIGEST_ALG_SHA384           MBEDTLS_OID_GOV "\x03\x04\x02\x02" /**< id-sha384 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 2 } */
+#define MBEDTLS_OID_DIGEST_ALG_SHA384           MBEDTLS_OID_NIST_ALG "\x02\x02" /**< id-sha384 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 2 } */
 
-#define MBEDTLS_OID_DIGEST_ALG_SHA512           MBEDTLS_OID_GOV "\x03\x04\x02\x03" /**< id-mbedtls_sha512 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 3 } */
+#define MBEDTLS_OID_DIGEST_ALG_SHA512           MBEDTLS_OID_NIST_ALG "\x02\x03" /**< id-mbedtls_sha512 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistalgorithm(4) hashalgs(2) 3 } */
+
+#define MBEDTLS_OID_DIGEST_ALG_RIPEMD160        MBEDTLS_OID_TELETRUST "\x03\x02\x01" /**< id-ripemd160 OBJECT IDENTIFIER :: { iso(1) identified-organization(3) teletrust(36) algorithm(3) hashAlgorithm(2) ripemd160(1) } */
 
 #define MBEDTLS_OID_HMAC_SHA1                   MBEDTLS_OID_RSA_COMPANY "\x02\x07" /**< id-hmacWithSHA1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 7 } */
 
+#define MBEDTLS_OID_HMAC_SHA224                 MBEDTLS_OID_RSA_COMPANY "\x02\x08" /**< id-hmacWithSHA224 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 8 } */
+
+#define MBEDTLS_OID_HMAC_SHA256                 MBEDTLS_OID_RSA_COMPANY "\x02\x09" /**< id-hmacWithSHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 9 } */
+
+#define MBEDTLS_OID_HMAC_SHA384                 MBEDTLS_OID_RSA_COMPANY "\x02\x0A" /**< id-hmacWithSHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 10 } */
+
+#define MBEDTLS_OID_HMAC_SHA512                 MBEDTLS_OID_RSA_COMPANY "\x02\x0B" /**< id-hmacWithSHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) digestAlgorithm(2) 11 } */
+
 /*
  * Encryption algorithms
  */
 #define MBEDTLS_OID_DES_CBC                     MBEDTLS_OID_ISO_IDENTIFIED_ORG MBEDTLS_OID_OIW_SECSIG_ALG "\x07" /**< desCBC OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) oiw(14) secsig(3) algorithms(2) 7 } */
 #define MBEDTLS_OID_DES_EDE3_CBC                MBEDTLS_OID_RSA_COMPANY "\x03\x07" /**< des-ede3-cbc OBJECT IDENTIFIER ::= { iso(1) member-body(2) -- us(840) rsadsi(113549) encryptionAlgorithm(3) 7 } */
+#define MBEDTLS_OID_AES                         MBEDTLS_OID_NIST_ALG "\x01" /** aes OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) nistAlgorithm(4) 1 } */
 
 /*
+ * Key Wrapping algorithms
+ */
+/*
+ * RFC 5649
+ */
+#define MBEDTLS_OID_AES128_KW                   MBEDTLS_OID_AES "\x05" /** id-aes128-wrap     OBJECT IDENTIFIER ::= { aes 5 } */
+#define MBEDTLS_OID_AES128_KWP                  MBEDTLS_OID_AES "\x08" /** id-aes128-wrap-pad OBJECT IDENTIFIER ::= { aes 8 } */
+#define MBEDTLS_OID_AES192_KW                   MBEDTLS_OID_AES "\x19" /** id-aes192-wrap     OBJECT IDENTIFIER ::= { aes 25 } */
+#define MBEDTLS_OID_AES192_KWP                  MBEDTLS_OID_AES "\x1c" /** id-aes192-wrap-pad OBJECT IDENTIFIER ::= { aes 28 } */
+#define MBEDTLS_OID_AES256_KW                   MBEDTLS_OID_AES "\x2d" /** id-aes256-wrap     OBJECT IDENTIFIER ::= { aes 45 } */
+#define MBEDTLS_OID_AES256_KWP                  MBEDTLS_OID_AES "\x30" /** id-aes256-wrap-pad OBJECT IDENTIFIER ::= { aes 48 } */
+/*
  * PKCS#5 OIDs
  */
 #define MBEDTLS_OID_PKCS5_PBKDF2                MBEDTLS_OID_PKCS5 "\x0c" /**< id-PBKDF2 OBJECT IDENTIFIER ::= {pkcs-5 12} */
@@ -243,8 +295,6 @@
 /*
  * PKCS#5 PBES1 algorithms
  */
-#define MBEDTLS_OID_PKCS5_PBE_MD2_DES_CBC       MBEDTLS_OID_PKCS5 "\x01" /**< pbeWithMD2AndDES-CBC OBJECT IDENTIFIER ::= {pkcs-5 1} */
-#define MBEDTLS_OID_PKCS5_PBE_MD2_RC2_CBC       MBEDTLS_OID_PKCS5 "\x04" /**< pbeWithMD2AndRC2-CBC OBJECT IDENTIFIER ::= {pkcs-5 4} */
 #define MBEDTLS_OID_PKCS5_PBE_MD5_DES_CBC       MBEDTLS_OID_PKCS5 "\x03" /**< pbeWithMD5AndDES-CBC OBJECT IDENTIFIER ::= {pkcs-5 3} */
 #define MBEDTLS_OID_PKCS5_PBE_MD5_RC2_CBC       MBEDTLS_OID_PKCS5 "\x06" /**< pbeWithMD5AndRC2-CBC OBJECT IDENTIFIER ::= {pkcs-5 6} */
 #define MBEDTLS_OID_PKCS5_PBE_SHA1_DES_CBC      MBEDTLS_OID_PKCS5 "\x0a" /**< pbeWithSHA1AndDES-CBC OBJECT IDENTIFIER ::= {pkcs-5 10} */
@@ -260,8 +310,6 @@
  */
 #define MBEDTLS_OID_PKCS12_PBE                      MBEDTLS_OID_PKCS12 "\x01" /**< pkcs-12PbeIds OBJECT IDENTIFIER ::= {pkcs-12 1} */
 
-#define MBEDTLS_OID_PKCS12_PBE_SHA1_RC4_128         MBEDTLS_OID_PKCS12_PBE "\x01" /**< pbeWithSHAAnd128BitRC4 OBJECT IDENTIFIER ::= {pkcs-12PbeIds 1} */
-#define MBEDTLS_OID_PKCS12_PBE_SHA1_RC4_40          MBEDTLS_OID_PKCS12_PBE "\x02" /**< pbeWithSHAAnd40BitRC4 OBJECT IDENTIFIER ::= {pkcs-12PbeIds 2} */
 #define MBEDTLS_OID_PKCS12_PBE_SHA1_DES3_EDE_CBC    MBEDTLS_OID_PKCS12_PBE "\x03" /**< pbeWithSHAAnd3-KeyTripleDES-CBC OBJECT IDENTIFIER ::= {pkcs-12PbeIds 3} */
 #define MBEDTLS_OID_PKCS12_PBE_SHA1_DES2_EDE_CBC    MBEDTLS_OID_PKCS12_PBE "\x04" /**< pbeWithSHAAnd2-KeyTripleDES-CBC OBJECT IDENTIFIER ::= {pkcs-12PbeIds 4} */
 #define MBEDTLS_OID_PKCS12_PBE_SHA1_RC2_128_CBC     MBEDTLS_OID_PKCS12_PBE "\x05" /**< pbeWithSHAAnd128BitRC2-CBC OBJECT IDENTIFIER ::= {pkcs-12PbeIds 5} */
@@ -379,11 +427,14 @@
 /**
  * \brief Base OID descriptor structure
  */
-typedef struct {
-    const char *asn1;               /*!< OID ASN.1 representation       */
-    size_t asn1_len;                /*!< length of asn1                 */
-    const char *name;               /*!< official name (e.g. from RFC)  */
-    const char *description;        /*!< human friendly description     */
+typedef struct mbedtls_oid_descriptor_t
+{
+    const char *MBEDTLS_PRIVATE(asn1);               /*!< OID ASN.1 representation       */
+    size_t MBEDTLS_PRIVATE(asn1_len);                /*!< length of asn1                 */
+#if !defined(MBEDTLS_X509_REMOVE_INFO)
+    const char *MBEDTLS_PRIVATE(name);               /*!< official name (e.g. from RFC)  */
+    const char *MBEDTLS_PRIVATE(description);        /*!< human friendly description     */
+#endif
 } mbedtls_oid_descriptor_t;
 
 /**
@@ -399,7 +450,6 @@
  */
 int mbedtls_oid_get_numeric_string( char *buf, size_t size, const mbedtls_asn1_buf *oid );
 
-#if defined(MBEDTLS_X509_USE_C) || defined(MBEDTLS_X509_CREATE_C)
 /**
  * \brief          Translate an X.509 extension OID into local values
  *
@@ -409,7 +459,6 @@
  * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
  */
 int mbedtls_oid_get_x509_ext_type( const mbedtls_asn1_buf *oid, int *ext_type );
-#endif
 
 /**
  * \brief          Translate an X.509 attribute type OID into the short name
@@ -513,8 +562,19 @@
  * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
  */
 int mbedtls_oid_get_md_alg( const mbedtls_asn1_buf *oid, mbedtls_md_type_t *md_alg );
+
+/**
+ * \brief          Translate hmac algorithm OID into md_type
+ *
+ * \param oid      OID to use
+ * \param md_hmac  place to store message hmac algorithm
+ *
+ * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
+ */
+int mbedtls_oid_get_md_hmac( const mbedtls_asn1_buf *oid, mbedtls_md_type_t *md_hmac );
 #endif /* MBEDTLS_MD_C */
 
+#if !defined(MBEDTLS_X509_REMOVE_INFO)
 /**
  * \brief          Translate Extended Key Usage OID into description
  *
@@ -524,6 +584,17 @@
  * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
  */
 int mbedtls_oid_get_extended_key_usage( const mbedtls_asn1_buf *oid, const char **desc );
+#endif
+
+/**
+ * \brief          Translate certificate policies OID into description
+ *
+ * \param oid      OID to use
+ * \param desc     place to store string pointer
+ *
+ * \return         0 if successful, or MBEDTLS_ERR_OID_NOT_FOUND
+ */
+int mbedtls_oid_get_certificate_policies( const mbedtls_asn1_buf *oid, const char **desc );
 
 /**
  * \brief          Translate md_type into hash algorithm OID
diff --git a/ext/mbedtls-asn1/include/mbedtls/pk.h b/ext/mbedtls-asn1/include/mbedtls/pk.h
index df3a03c..f3553cc 100644
--- a/ext/mbedtls-asn1/include/mbedtls/pk.h
+++ b/ext/mbedtls-asn1/include/mbedtls/pk.h
@@ -4,7 +4,7 @@
  * \brief Public Key abstraction layer
  */
 /*
- *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -18,31 +18,30 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 
 #ifndef MBEDTLS_PK_H
 #define MBEDTLS_PK_H
+#include "mbedtls/private_access.h"
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
-#include "md.h"
+#include "mbedtls/md.h"
 
 #if defined(MBEDTLS_RSA_C)
-#include "rsa.h"
+#include "mbedtls/rsa.h"
 #endif
 
 #if defined(MBEDTLS_ECP_C)
-#include "ecp.h"
+#include "mbedtls/ecp.h"
 #endif
 
 #if defined(MBEDTLS_ECDSA_C)
-#include "ecdsa.h"
+#include "mbedtls/ecdsa.h"
+#endif
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+#include "psa/crypto.h"
 #endif
 
 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
@@ -64,9 +63,7 @@
 #define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00  /**< Elliptic curve is unsupported (only NIST curves are supported). */
 #define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980  /**< Unavailable feature, e.g. RSA disabled for RSA key. */
 #define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH    -0x3900  /**< The buffer contains a valid signature followed by more data. */
-
-/* MBEDTLS_ERR_PK_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_PK_HW_ACCEL_FAILED     -0x3880  /**< PK hardware accelerator failed. */
+#define MBEDTLS_ERR_PK_BUFFER_TOO_SMALL    -0x3880  /**< The output buffer is too small. */
 
 #ifdef __cplusplus
 extern "C" {
@@ -83,6 +80,7 @@
     MBEDTLS_PK_ECDSA,
     MBEDTLS_PK_RSA_ALT,
     MBEDTLS_PK_RSASSA_PSS,
+    MBEDTLS_PK_OPAQUE,
 } mbedtls_pk_type_t;
 
 /**
@@ -91,12 +89,64 @@
  */
 typedef struct mbedtls_pk_rsassa_pss_options
 {
-    mbedtls_md_type_t mgf1_hash_id;
-    int expected_salt_len;
+    mbedtls_md_type_t MBEDTLS_PRIVATE(mgf1_hash_id);
+    int MBEDTLS_PRIVATE(expected_salt_len);
 
 } mbedtls_pk_rsassa_pss_options;
 
 /**
+ * \brief           Maximum size of a signature made by mbedtls_pk_sign().
+ */
+/* We need to set MBEDTLS_PK_SIGNATURE_MAX_SIZE to the maximum signature
+ * size among the supported signature types. Do it by starting at 0,
+ * then incrementally increasing to be large enough for each supported
+ * signature mechanism.
+ *
+ * The resulting value can be 0, for example if MBEDTLS_ECDH_C is enabled
+ * (which allows the pk module to be included) but neither MBEDTLS_ECDSA_C
+ * nor MBEDTLS_RSA_C nor any opaque signature mechanism (PSA or RSA_ALT).
+ */
+#define MBEDTLS_PK_SIGNATURE_MAX_SIZE 0
+
+#if ( defined(MBEDTLS_RSA_C) || defined(MBEDTLS_PK_RSA_ALT_SUPPORT) ) && \
+    MBEDTLS_MPI_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE
+/* For RSA, the signature can be as large as the bignum module allows.
+ * For RSA_ALT, the signature size is not necessarily tied to what the
+ * bignum module can do, but in the absence of any specific setting,
+ * we use that (rsa_alt_sign_wrap in library/pk_wrap.h will check). */
+#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
+#define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_MPI_MAX_SIZE
+#endif
+
+#if defined(MBEDTLS_ECDSA_C) &&                                 \
+    MBEDTLS_ECDSA_MAX_LEN > MBEDTLS_PK_SIGNATURE_MAX_SIZE
+/* For ECDSA, the ecdsa module exports a constant for the maximum
+ * signature size. */
+#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
+#define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_ECDSA_MAX_LEN
+#endif
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+#if PSA_SIGNATURE_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE
+/* PSA_SIGNATURE_MAX_SIZE is the maximum size of a signature made
+ * through the PSA API in the PSA representation. */
+#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
+#define MBEDTLS_PK_SIGNATURE_MAX_SIZE PSA_SIGNATURE_MAX_SIZE
+#endif
+
+#if PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 > MBEDTLS_PK_SIGNATURE_MAX_SIZE
+/* The Mbed TLS representation is different for ECDSA signatures:
+ * PSA uses the raw concatenation of r and s,
+ * whereas Mbed TLS uses the ASN.1 representation (SEQUENCE of two INTEGERs).
+ * Add the overhead of ASN.1: up to (1+2) + 2 * (1+2+1) for the
+ * types, lengths (represented by up to 2 bytes), and potential leading
+ * zeros of the INTEGERs and the SEQUENCE. */
+#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE
+#define MBEDTLS_PK_SIGNATURE_MAX_SIZE ( PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 )
+#endif
+#endif /* defined(MBEDTLS_USE_PSA_CRYPTO) */
+
+/**
  * \brief           Types for interfacing with the debug module
  */
 typedef enum
@@ -111,9 +161,9 @@
  */
 typedef struct mbedtls_pk_debug_item
 {
-    mbedtls_pk_debug_type type;
-    const char *name;
-    void *value;
+    mbedtls_pk_debug_type MBEDTLS_PRIVATE(type);
+    const char *MBEDTLS_PRIVATE(name);
+    void *MBEDTLS_PRIVATE(value);
 } mbedtls_pk_debug_item;
 
 /** Maximum number of item send for debugging, plus 1 */
@@ -129,8 +179,8 @@
  */
 typedef struct mbedtls_pk_context
 {
-    const mbedtls_pk_info_t *   pk_info; /**< Public key information         */
-    void *                      pk_ctx;  /**< Underlying public key context  */
+    const mbedtls_pk_info_t *   MBEDTLS_PRIVATE(pk_info); /**< Public key information         */
+    void *                      MBEDTLS_PRIVATE(pk_ctx);  /**< Underlying public key context  */
 } mbedtls_pk_context;
 
 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
@@ -139,8 +189,8 @@
  */
 typedef struct
 {
-    const mbedtls_pk_info_t *   pk_info; /**< Public key information         */
-    void *                      rs_ctx;  /**< Underlying restart context     */
+    const mbedtls_pk_info_t *   MBEDTLS_PRIVATE(pk_info); /**< Public key information         */
+    void *                      MBEDTLS_PRIVATE(rs_ctx);  /**< Underlying restart context     */
 } mbedtls_pk_restart_ctx;
 #else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
 /* Now we can declare functions that take a pointer to that */
@@ -156,7 +206,7 @@
  */
 static inline mbedtls_rsa_context *mbedtls_pk_rsa( const mbedtls_pk_context pk )
 {
-    return( (mbedtls_rsa_context *) (pk).pk_ctx );
+    return( (mbedtls_rsa_context *) (pk).MBEDTLS_PRIVATE(pk_ctx) );
 }
 #endif /* MBEDTLS_RSA_C */
 
@@ -169,7 +219,7 @@
  */
 static inline mbedtls_ecp_keypair *mbedtls_pk_ec( const mbedtls_pk_context pk )
 {
-    return( (mbedtls_ecp_keypair *) (pk).pk_ctx );
+    return( (mbedtls_ecp_keypair *) (pk).MBEDTLS_PRIVATE(pk_ctx) );
 }
 #endif /* MBEDTLS_ECP_C */
 
@@ -177,12 +227,12 @@
 /**
  * \brief           Types for RSA-alt abstraction
  */
-typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, int mode, size_t *olen,
+typedef int (*mbedtls_pk_rsa_alt_decrypt_func)( void *ctx, size_t *olen,
                     const unsigned char *input, unsigned char *output,
                     size_t output_max_len );
 typedef int (*mbedtls_pk_rsa_alt_sign_func)( void *ctx,
                     int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
-                    int mode, mbedtls_md_type_t md_alg, unsigned int hashlen,
+                    mbedtls_md_type_t md_alg, unsigned int hashlen,
                     const unsigned char *hash, unsigned char *sig );
 typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)( void *ctx );
 #endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
@@ -197,23 +247,40 @@
 const mbedtls_pk_info_t *mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type );
 
 /**
- * \brief           Initialize a mbedtls_pk_context (as NONE)
+ * \brief           Initialize a #mbedtls_pk_context (as NONE).
+ *
+ * \param ctx       The context to initialize.
+ *                  This must not be \c NULL.
  */
 void mbedtls_pk_init( mbedtls_pk_context *ctx );
 
 /**
- * \brief           Free a mbedtls_pk_context
+ * \brief           Free the components of a #mbedtls_pk_context.
+ *
+ * \param ctx       The context to clear. It must have been initialized.
+ *                  If this is \c NULL, this function does nothing.
+ *
+ * \note            For contexts that have been set up with
+ *                  mbedtls_pk_setup_opaque(), this does not free the underlying
+ *                  PSA key and you still need to call psa_destroy_key()
+ *                  independently if you want to destroy that key.
  */
 void mbedtls_pk_free( mbedtls_pk_context *ctx );
 
 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
 /**
  * \brief           Initialize a restart context
+ *
+ * \param ctx       The context to initialize.
+ *                  This must not be \c NULL.
  */
 void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx );
 
 /**
  * \brief           Free the components of a restart context
+ *
+ * \param ctx       The context to clear. It must have been initialized.
+ *                  If this is \c NULL, this function does nothing.
  */
 void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx );
 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
@@ -222,7 +289,8 @@
  * \brief           Initialize a PK context with the information given
  *                  and allocates the type-specific PK subcontext.
  *
- * \param ctx       Context to initialize. Must be empty (type NONE).
+ * \param ctx       Context to initialize. It must not have been set
+ *                  up yet (type #MBEDTLS_PK_NONE).
  * \param info      Information to use
  *
  * \return          0 on success,
@@ -234,11 +302,45 @@
  */
 int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info );
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+/**
+ * \brief           Initialize a PK context to wrap a PSA key.
+ *
+ * \note            This function replaces mbedtls_pk_setup() for contexts
+ *                  that wrap a (possibly opaque) PSA key instead of
+ *                  storing and manipulating the key material directly.
+ *
+ * \param ctx       The context to initialize. It must be empty (type NONE).
+ * \param key       The PSA key to wrap, which must hold an ECC key pair
+ *                  (see notes below).
+ *
+ * \note            The wrapped key must remain valid as long as the
+ *                  wrapping PK context is in use, that is at least between
+ *                  the point this function is called and the point
+ *                  mbedtls_pk_free() is called on this context. The wrapped
+ *                  key might then be independently used or destroyed.
+ *
+ * \note            This function is currently only available for ECC key
+ *                  pairs (that is, ECC keys containing private key material).
+ *                  Support for other key types may be added later.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input
+ *                  (context already used, invalid key identifier).
+ * \return          #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the key is not an
+ *                  ECC key pair.
+ * \return          #MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure.
+ */
+int mbedtls_pk_setup_opaque( mbedtls_pk_context *ctx,
+                             const psa_key_id_t key );
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
 #if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
 /**
  * \brief           Initialize an RSA-alt context
  *
- * \param ctx       Context to initialize. Must be empty (type NONE).
+ * \param ctx       Context to initialize. It must not have been set
+ *                  up yet (type #MBEDTLS_PK_NONE).
  * \param key       RSA key pointer
  * \param decrypt_func  Decryption function
  * \param sign_func     Signing function
@@ -258,7 +360,7 @@
 /**
  * \brief           Get the size in bits of the underlying key
  *
- * \param ctx       Context to use
+ * \param ctx       The context to query. It must have been initialized.
  *
  * \return          Key size in bits, or 0 on error
  */
@@ -266,7 +368,8 @@
 
 /**
  * \brief           Get the length in bytes of the underlying key
- * \param ctx       Context to use
+ *
+ * \param ctx       The context to query. It must have been initialized.
  *
  * \return          Key length in bytes, or 0 on error
  */
@@ -278,21 +381,32 @@
 /**
  * \brief           Tell if a context can do the operation given by type
  *
- * \param ctx       Context to test
- * \param type      Target type
+ * \param ctx       The context to query. It must have been initialized.
+ * \param type      The desired type.
  *
- * \return          0 if context can't do the operations,
- *                  1 otherwise.
+ * \return          1 if the context can do operations on the given type.
+ * \return          0 if the context cannot do the operations on the given
+ *                  type. This is always the case for a context that has
+ *                  been initialized but not set up, or that has been
+ *                  cleared with mbedtls_pk_free().
  */
 int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
 
 /**
  * \brief           Verify signature (including padding if relevant).
  *
- * \param ctx       PK context to use
- * \param md_alg    Hash algorithm used (see notes)
+ * \param ctx       The PK context to use. It must have been set up.
+ * \param md_alg    Hash algorithm used.
+ *                  This can be #MBEDTLS_MD_NONE if the signature algorithm
+ *                  does not rely on a hash algorithm (non-deterministic
+ *                  ECDSA, RSA PKCS#1 v1.5).
+ *                  For PKCS#1 v1.5, if \p md_alg is #MBEDTLS_MD_NONE, then
+ *                  \p hash is the DigestInfo structure used by RFC 8017
+ *                  &sect;9.2 steps 3&ndash;6. If \p md_alg is a valid hash
+ *                  algorithm then \p hash is the digest itself, and this
+ *                  function calculates the DigestInfo encoding internally.
  * \param hash      Hash of the message to sign
- * \param hash_len  Hash length or 0 (see notes)
+ * \param hash_len  Hash length
  * \param sig       Signature to verify
  * \param sig_len   Signature length
  *
@@ -304,11 +418,6 @@
  * \note            For RSA keys, the default padding type is PKCS#1 v1.5.
  *                  Use \c mbedtls_pk_verify_ext( MBEDTLS_PK_RSASSA_PSS, ... )
  *                  to verify RSASSA_PSS signatures.
- *
- * \note            If hash_len is 0, then the length associated with md_alg
- *                  is used instead, or an error returned if it is invalid.
- *
- * \note            md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0
  */
 int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
                const unsigned char *hash, size_t hash_len,
@@ -322,7 +431,7 @@
  *                  \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
  *                  operations. For RSA, same as \c mbedtls_pk_verify().
  *
- * \param ctx       PK context to use
+ * \param ctx       The PK context to use. It must have been set up.
  * \param md_alg    Hash algorithm used (see notes)
  * \param hash      Hash of the message to sign
  * \param hash_len  Hash length or 0 (see notes)
@@ -346,7 +455,7 @@
  *
  * \param type      Signature type (inc. possible padding type) to verify
  * \param options   Pointer to type-specific options, or NULL
- * \param ctx       PK context to use
+ * \param ctx       The PK context to use. It must have been set up.
  * \param md_alg    Hash algorithm used (see notes)
  * \param hash      Hash of the message to sign
  * \param hash_len  Hash length or 0 (see notes)
@@ -377,13 +486,20 @@
 /**
  * \brief           Make signature, including padding if relevant.
  *
- * \param ctx       PK context to use - must hold a private key
+ * \param ctx       The PK context to use. It must have been set up
+ *                  with a private key.
  * \param md_alg    Hash algorithm used (see notes)
  * \param hash      Hash of the message to sign
- * \param hash_len  Hash length or 0 (see notes)
- * \param sig       Place to write the signature
- * \param sig_len   Number of bytes written
- * \param f_rng     RNG function
+ * \param hash_len  Hash length
+ * \param sig       Place to write the signature.
+ *                  It must have enough room for the signature.
+ *                  #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
+ *                  You may use a smaller buffer if it is large enough
+ *                  given the key type.
+ * \param sig_size  The size of the \p sig buffer in bytes.
+ * \param sig_len   On successful return,
+ *                  the number of bytes written to \p sig.
+ * \param f_rng     RNG function, must not be \c NULL.
  * \param p_rng     RNG parameter
  *
  * \return          0 on success, or a specific error code.
@@ -392,15 +508,12 @@
  *                  There is no interface in the PK module to make RSASSA-PSS
  *                  signatures yet.
  *
- * \note            If hash_len is 0, then the length associated with md_alg
- *                  is used instead, or an error returned if it is invalid.
- *
  * \note            For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0.
  *                  For ECDSA, md_alg may never be MBEDTLS_MD_NONE.
  */
 int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
              const unsigned char *hash, size_t hash_len,
-             unsigned char *sig, size_t *sig_len,
+             unsigned char *sig, size_t sig_size, size_t *sig_len,
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 /**
@@ -411,37 +524,45 @@
  *                  \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC
  *                  operations. For RSA, same as \c mbedtls_pk_sign().
  *
- * \param ctx       PK context to use - must hold a private key
- * \param md_alg    Hash algorithm used (see notes)
+ * \param ctx       The PK context to use. It must have been set up
+ *                  with a private key.
+ * \param md_alg    Hash algorithm used (see notes for mbedtls_pk_sign())
  * \param hash      Hash of the message to sign
- * \param hash_len  Hash length or 0 (see notes)
- * \param sig       Place to write the signature
- * \param sig_len   Number of bytes written
- * \param f_rng     RNG function
+ * \param hash_len  Hash length
+ * \param sig       Place to write the signature.
+ *                  It must have enough room for the signature.
+ *                  #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough.
+ *                  You may use a smaller buffer if it is large enough
+ *                  given the key type.
+ * \param sig_size  The size of the \p sig buffer in bytes.
+ * \param sig_len   On successful return,
+ *                  the number of bytes written to \p sig.
+ * \param f_rng     RNG function, must not be \c NULL.
  * \param p_rng     RNG parameter
  * \param rs_ctx    Restart context (NULL to disable restart)
  *
- * \return          See \c mbedtls_pk_sign(), or
+ * \return          See \c mbedtls_pk_sign().
  * \return          #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
  *                  operations was reached: see \c mbedtls_ecp_set_max_ops().
  */
 int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
              mbedtls_md_type_t md_alg,
              const unsigned char *hash, size_t hash_len,
-             unsigned char *sig, size_t *sig_len,
+             unsigned char *sig, size_t sig_size, size_t *sig_len,
              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
              mbedtls_pk_restart_ctx *rs_ctx );
 
 /**
  * \brief           Decrypt message (including padding if relevant).
  *
- * \param ctx       PK context to use - must hold a private key
+ * \param ctx       The PK context to use. It must have been set up
+ *                  with a private key.
  * \param input     Input to decrypt
  * \param ilen      Input size
  * \param output    Decrypted output
  * \param olen      Decrypted message length
  * \param osize     Size of the output buffer
- * \param f_rng     RNG function
+ * \param f_rng     RNG function, must not be \c NULL.
  * \param p_rng     RNG parameter
  *
  * \note            For RSA keys, the default padding type is PKCS#1 v1.5.
@@ -456,15 +577,17 @@
 /**
  * \brief           Encrypt message (including padding if relevant).
  *
- * \param ctx       PK context to use
+ * \param ctx       The PK context to use. It must have been set up.
  * \param input     Message to encrypt
  * \param ilen      Message size
  * \param output    Encrypted output
  * \param olen      Encrypted output length
  * \param osize     Size of the output buffer
- * \param f_rng     RNG function
+ * \param f_rng     RNG function, must not be \c NULL.
  * \param p_rng     RNG parameter
  *
+ * \note            \p f_rng is used for padding generation.
+ *
  * \note            For RSA keys, the default padding type is PKCS#1 v1.5.
  *
  * \return          0 on success, or a specific error code.
@@ -479,15 +602,24 @@
  *
  * \param pub       Context holding a public key.
  * \param prv       Context holding a private (and public) key.
+ * \param f_rng     RNG function, must not be \c NULL.
+ * \param p_rng     RNG parameter
  *
- * \return          0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
+ * \return          \c 0 on success (keys were checked and match each other).
+ * \return          #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not
+ *                  be checked - in that case they may or may not match.
+ * \return          #MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid.
+ * \return          Another non-zero value if the keys do not match.
  */
-int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv );
+int mbedtls_pk_check_pair( const mbedtls_pk_context *pub,
+                           const mbedtls_pk_context *prv,
+                           int (*f_rng)(void *, unsigned char *, size_t),
+                           void *p_rng );
 
 /**
  * \brief           Export debug information
  *
- * \param ctx       Context to use
+ * \param ctx       The PK context to use. It must have been initialized.
  * \param items     Place to write debug items
  *
  * \return          0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA
@@ -497,7 +629,7 @@
 /**
  * \brief           Access the type name
  *
- * \param ctx       Context to use
+ * \param ctx       The PK context to use. It must have been initialized.
  *
  * \return          Type name on success, or "invalid PK"
  */
@@ -506,9 +638,10 @@
 /**
  * \brief           Get the key type
  *
- * \param ctx       Context to use
+ * \param ctx       The PK context to use. It must have been initialized.
  *
- * \return          Type on success, or MBEDTLS_PK_NONE
+ * \return          Type on success.
+ * \return          #MBEDTLS_PK_NONE for a context that has not been set up.
  */
 mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx );
 
@@ -517,12 +650,24 @@
 /**
  * \brief           Parse a private key in PEM or DER format
  *
- * \param ctx       key to be initialized
- * \param key       input buffer
- * \param keylen    size of the buffer
- *                  (including the terminating null byte for PEM data)
- * \param pwd       password for decryption (optional)
- * \param pwdlen    size of the password
+ * \param ctx       The PK context to fill. It must have been initialized
+ *                  but not set up.
+ * \param key       Input buffer to parse.
+ *                  The buffer must contain the input exactly, with no
+ *                  extra trailing material. For PEM, the buffer must
+ *                  contain a null-terminated string.
+ * \param keylen    Size of \b key in bytes.
+ *                  For PEM data, this includes the terminating null byte,
+ *                  so \p keylen must be equal to `strlen(key) + 1`.
+ * \param pwd       Optional password for decryption.
+ *                  Pass \c NULL if expecting a non-encrypted key.
+ *                  Pass a string of \p pwdlen bytes if expecting an encrypted
+ *                  key; a non-encrypted key will also be accepted.
+ *                  The empty password is not supported.
+ * \param pwdlen    Size of the password in bytes.
+ *                  Ignored if \p pwd is \c NULL.
+ * \param f_rng     RNG function, must not be \c NULL. Used for blinding.
+ * \param p_rng     RNG parameter
  *
  * \note            On entry, ctx must be empty, either freshly initialised
  *                  with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
@@ -533,17 +678,23 @@
  * \return          0 if successful, or a specific PK or PEM error code
  */
 int mbedtls_pk_parse_key( mbedtls_pk_context *ctx,
-                  const unsigned char *key, size_t keylen,
-                  const unsigned char *pwd, size_t pwdlen );
+              const unsigned char *key, size_t keylen,
+              const unsigned char *pwd, size_t pwdlen,
+              int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 /** \ingroup pk_module */
 /**
  * \brief           Parse a public key in PEM or DER format
  *
- * \param ctx       key to be initialized
- * \param key       input buffer
- * \param keylen    size of the buffer
- *                  (including the terminating null byte for PEM data)
+ * \param ctx       The PK context to fill. It must have been initialized
+ *                  but not set up.
+ * \param key       Input buffer to parse.
+ *                  The buffer must contain the input exactly, with no
+ *                  extra trailing material. For PEM, the buffer must
+ *                  contain a null-terminated string.
+ * \param keylen    Size of \b key in bytes.
+ *                  For PEM data, this includes the terminating null byte,
+ *                  so \p keylen must be equal to `strlen(key) + 1`.
  *
  * \note            On entry, ctx must be empty, either freshly initialised
  *                  with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
@@ -561,9 +712,16 @@
 /**
  * \brief           Load and parse a private key
  *
- * \param ctx       key to be initialized
+ * \param ctx       The PK context to fill. It must have been initialized
+ *                  but not set up.
  * \param path      filename to read the private key from
- * \param password  password to decrypt the file (can be NULL)
+ * \param password  Optional password to decrypt the file.
+ *                  Pass \c NULL if expecting a non-encrypted key.
+ *                  Pass a null-terminated string if expecting an encrypted
+ *                  key; a non-encrypted key will also be accepted.
+ *                  The empty password is not supported.
+ * \param f_rng     RNG function, must not be \c NULL. Used for blinding.
+ * \param p_rng     RNG parameter
  *
  * \note            On entry, ctx must be empty, either freshly initialised
  *                  with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
@@ -574,13 +732,15 @@
  * \return          0 if successful, or a specific PK or PEM error code
  */
 int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
-                      const char *path, const char *password );
+                  const char *path, const char *password,
+                  int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
 
 /** \ingroup pk_module */
 /**
  * \brief           Load and parse a public key
  *
- * \param ctx       key to be initialized
+ * \param ctx       The PK context to fill. It must have been initialized
+ *                  but not set up.
  * \param path      filename to read the public key from
  *
  * \note            On entry, ctx must be empty, either freshly initialised
@@ -603,14 +763,14 @@
  *                        return value to determine where you should start
  *                        using the buffer
  *
- * \param ctx       private to write away
+ * \param ctx       PK context which must contain a valid private key.
  * \param buf       buffer to write to
  * \param size      size of the buffer
  *
  * \return          length of data written if successful, or a specific
  *                  error code
  */
-int mbedtls_pk_write_key_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
+int mbedtls_pk_write_key_der( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
 
 /**
  * \brief           Write a public key to a SubjectPublicKeyInfo DER structure
@@ -618,37 +778,39 @@
  *                        return value to determine where you should start
  *                        using the buffer
  *
- * \param ctx       public key to write away
+ * \param ctx       PK context which must contain a valid public or private key.
  * \param buf       buffer to write to
  * \param size      size of the buffer
  *
  * \return          length of data written if successful, or a specific
  *                  error code
  */
-int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
+int mbedtls_pk_write_pubkey_der( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
 
 #if defined(MBEDTLS_PEM_WRITE_C)
 /**
  * \brief           Write a public key to a PEM string
  *
- * \param ctx       public key to write away
- * \param buf       buffer to write to
- * \param size      size of the buffer
+ * \param ctx       PK context which must contain a valid public or private key.
+ * \param buf       Buffer to write to. The output includes a
+ *                  terminating null byte.
+ * \param size      Size of the buffer in bytes.
  *
  * \return          0 if successful, or a specific error code
  */
-int mbedtls_pk_write_pubkey_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
+int mbedtls_pk_write_pubkey_pem( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
 
 /**
  * \brief           Write a private key to a PKCS#1 or SEC1 PEM string
  *
- * \param ctx       private to write away
- * \param buf       buffer to write to
- * \param size      size of the buffer
+ * \param ctx       PK context which must contain a valid private key.
+ * \param buf       Buffer to write to. The output includes a
+ *                  terminating null byte.
+ * \param size      Size of the buffer in bytes.
  *
  * \return          0 if successful, or a specific error code
  */
-int mbedtls_pk_write_key_pem( mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
+int mbedtls_pk_write_key_pem( const mbedtls_pk_context *ctx, unsigned char *buf, size_t size );
 #endif /* MBEDTLS_PEM_WRITE_C */
 #endif /* MBEDTLS_PK_WRITE_C */
 
@@ -663,7 +825,8 @@
  *
  * \param p         the position in the ASN.1 data
  * \param end       end of the buffer
- * \param pk        the key to fill
+ * \param pk        The PK context to fill. It must have been initialized
+ *                  but not set up.
  *
  * \return          0 if successful, or a specific PK error code
  */
@@ -678,7 +841,7 @@
  *
  * \param p         reference to current position pointer
  * \param start     start of the buffer (for bounds-checking)
- * \param key       public key to write away
+ * \param key       PK context which must contain a valid public or private key.
  *
  * \return          the length written or a negative error code
  */
@@ -694,6 +857,32 @@
 int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n );
 #endif
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+/**
+ * \brief           Turn an EC key into an opaque one.
+ *
+ * \warning         This is a temporary utility function for tests. It might
+ *                  change or be removed at any time without notice.
+ *
+ * \note            Only ECDSA keys are supported so far. Signing with the
+ *                  specified hash is the only allowed use of that key.
+ *
+ * \param pk        Input: the EC key to import to a PSA key.
+ *                  Output: a PK context wrapping that PSA key.
+ * \param key       Output: a PSA key identifier.
+ *                  It's the caller's responsibility to call
+ *                  psa_destroy_key() on that key identifier after calling
+ *                  mbedtls_pk_free() on the PK context.
+ * \param hash_alg  The hash algorithm to allow for use with that key.
+ *
+ * \return          \c 0 if successful.
+ * \return          An Mbed TLS error code otherwise.
+ */
+int mbedtls_pk_wrap_as_opaque( mbedtls_pk_context *pk,
+                               psa_key_id_t *key,
+                               psa_algorithm_t hash_alg );
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/ext/mbedtls-asn1/include/mbedtls/platform.h b/ext/mbedtls-asn1/include/mbedtls/platform.h
index 89fe8a7..277a85c 100644
--- a/ext/mbedtls-asn1/include/mbedtls/platform.h
+++ b/ext/mbedtls-asn1/include/mbedtls/platform.h
@@ -13,7 +13,7 @@
  *        dynamically configured at runtime.
  */
 /*
- *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -27,25 +27,17 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of Mbed TLS (https://tls.mbed.org)
  */
 #ifndef MBEDTLS_PLATFORM_H
 #define MBEDTLS_PLATFORM_H
+#include "mbedtls/private_access.h"
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
 #if defined(MBEDTLS_HAVE_TIME)
-#include "platform_time.h"
+#include "mbedtls/platform_time.h"
 #endif
 
-#define MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED     -0x0070 /**< Hardware accelerator failed */
-#define MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED -0x0072 /**< The requested feature is not supported by the platform */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -54,21 +46,37 @@
  * \name SECTION: Module settings
  *
  * The configuration options you can set for this module are in this section.
- * Either change them in config.h or define them on the compiler command line.
+ * Either change them in mbedtls_config.h or define them on the compiler command line.
  * \{
  */
 
+/* The older Microsoft Windows common runtime provides non-conforming
+ * implementations of some standard library functions, including snprintf
+ * and vsnprintf. This affects MSVC and MinGW builds.
+ */
+#if defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER <= 1900)
+#define MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF
+#define MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF
+#endif
+
 #if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS)
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
 #if !defined(MBEDTLS_PLATFORM_STD_SNPRINTF)
-#if defined(_WIN32)
+#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF)
 #define MBEDTLS_PLATFORM_STD_SNPRINTF   mbedtls_platform_win32_snprintf /**< The default \c snprintf function to use.  */
 #else
 #define MBEDTLS_PLATFORM_STD_SNPRINTF   snprintf /**< The default \c snprintf function to use.  */
 #endif
 #endif
+#if !defined(MBEDTLS_PLATFORM_STD_VSNPRINTF)
+#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF)
+#define MBEDTLS_PLATFORM_STD_VSNPRINTF   mbedtls_platform_win32_vsnprintf /**< The default \c vsnprintf function to use.  */
+#else
+#define MBEDTLS_PLATFORM_STD_VSNPRINTF   vsnprintf /**< The default \c vsnprintf function to use.  */
+#endif
+#endif
 #if !defined(MBEDTLS_PLATFORM_STD_PRINTF)
 #define MBEDTLS_PLATFORM_STD_PRINTF   printf /**< The default \c printf function to use. */
 #endif
@@ -204,7 +212,7 @@
  * - however it is acceptable to return -1 instead of the required length when
  *   the destination buffer is too short.
  */
-#if defined(_WIN32)
+#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF)
 /* For Windows (inc. MSYS2), we provide our own fixed implementation */
 int mbedtls_platform_win32_snprintf( char *s, size_t n, const char *fmt, ... );
 #endif
@@ -231,6 +239,42 @@
 #endif /* MBEDTLS_PLATFORM_SNPRINTF_ALT */
 
 /*
+ * The function pointers for vsnprintf
+ *
+ * The vsnprintf implementation should conform to C99:
+ * - it *must* always correctly zero-terminate the buffer
+ *   (except when n == 0, then it must leave the buffer untouched)
+ * - however it is acceptable to return -1 instead of the required length when
+ *   the destination buffer is too short.
+ */
+#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF)
+#include <stdarg.h>
+/* For Older Windows (inc. MSYS2), we provide our own fixed implementation */
+int mbedtls_platform_win32_vsnprintf( char *s, size_t n, const char *fmt, va_list arg );
+#endif
+
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT)
+#include <stdarg.h>
+extern int (*mbedtls_vsnprintf)( char * s, size_t n, const char * format, va_list arg );
+
+/**
+ * \brief   Set your own snprintf function pointer
+ *
+ * \param   vsnprintf_func   The \c vsnprintf function implementation
+ *
+ * \return  \c 0
+ */
+int mbedtls_platform_set_vsnprintf( int (*vsnprintf_func)( char * s, size_t n,
+                                                 const char * format, va_list arg ) );
+#else /* MBEDTLS_PLATFORM_VSNPRINTF_ALT */
+#if defined(MBEDTLS_PLATFORM_VSNPRINTF_MACRO)
+#define mbedtls_vsnprintf   MBEDTLS_PLATFORM_VSNPRINTF_MACRO
+#else
+#define mbedtls_vsnprintf   vsnprintf
+#endif /* MBEDTLS_PLATFORM_VSNPRINTF_MACRO */
+#endif /* MBEDTLS_PLATFORM_VSNPRINTF_ALT */
+
+/*
  * The function pointers for exit
  */
 #if defined(MBEDTLS_PLATFORM_EXIT_ALT)
@@ -320,7 +364,7 @@
  */
 typedef struct mbedtls_platform_context
 {
-    char dummy; /**< A placeholder member, as empty structs are not portable. */
+    char MBEDTLS_PRIVATE(dummy); /**< A placeholder member, as empty structs are not portable. */
 }
 mbedtls_platform_context;
 
diff --git a/ext/mbedtls-asn1/include/mbedtls/platform_util.h b/ext/mbedtls-asn1/include/mbedtls/platform_util.h
index 164a1a0..1a0a135 100644
--- a/ext/mbedtls-asn1/include/mbedtls/platform_util.h
+++ b/ext/mbedtls-asn1/include/mbedtls/platform_util.h
@@ -5,7 +5,7 @@
  *        library.
  */
 /*
- *  Copyright (C) 2018, Arm Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -19,17 +19,11 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of Mbed TLS (https://tls.mbed.org)
  */
 #ifndef MBEDTLS_PLATFORM_UTIL_H
 #define MBEDTLS_PLATFORM_UTIL_H
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "mbedtls/config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
 #include <stddef.h>
 #if defined(MBEDTLS_HAVE_TIME_DATE)
@@ -41,6 +35,31 @@
 extern "C" {
 #endif
 
+/* Internal macros meant to be called only from within the library. */
+#define MBEDTLS_INTERNAL_VALIDATE_RET( cond, ret )  do { } while( 0 )
+#define MBEDTLS_INTERNAL_VALIDATE( cond )           do { } while( 0 )
+
+/* Internal helper macros for deprecating API constants. */
+#if !defined(MBEDTLS_DEPRECATED_REMOVED)
+#if defined(MBEDTLS_DEPRECATED_WARNING)
+/* Deliberately don't (yet) export MBEDTLS_DEPRECATED here
+ * to avoid conflict with other headers which define and use
+ * it, too. We might want to move all these definitions here at
+ * some point for uniformity. */
+#define MBEDTLS_DEPRECATED __attribute__((deprecated))
+MBEDTLS_DEPRECATED typedef char const * mbedtls_deprecated_string_constant_t;
+#define MBEDTLS_DEPRECATED_STRING_CONSTANT( VAL )       \
+    ( (mbedtls_deprecated_string_constant_t) ( VAL ) )
+MBEDTLS_DEPRECATED typedef int mbedtls_deprecated_numeric_constant_t;
+#define MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( VAL )       \
+    ( (mbedtls_deprecated_numeric_constant_t) ( VAL ) )
+#undef MBEDTLS_DEPRECATED
+#else /* MBEDTLS_DEPRECATED_WARNING */
+#define MBEDTLS_DEPRECATED_STRING_CONSTANT( VAL ) VAL
+#define MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( VAL ) VAL
+#endif /* MBEDTLS_DEPRECATED_WARNING */
+#endif /* MBEDTLS_DEPRECATED_REMOVED */
+
 /**
  * \brief       Securely zeroize a buffer
  *
diff --git a/ext/mbedtls-asn1/include/mbedtls/private_access.h b/ext/mbedtls-asn1/include/mbedtls/private_access.h
new file mode 100644
index 0000000..98d3419
--- /dev/null
+++ b/ext/mbedtls-asn1/include/mbedtls/private_access.h
@@ -0,0 +1,32 @@
+ /**
+ * \file private_access.h
+ *
+ * \brief Macro wrapper for struct's memebrs.
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#ifndef MBEDTLS_PRIVATE_ACCESS_H
+#define MBEDTLS_PRIVATE_ACCESS_H
+
+#ifndef MBEDTLS_ALLOW_PRIVATE_ACCESS
+#define MBEDTLS_PRIVATE(member) private_##member
+#else
+#define MBEDTLS_PRIVATE(member) member
+#endif
+
+#endif /* MBEDTLS_PRIVATE_ACCESS_H */
diff --git a/ext/mbedtls-asn1/include/mbedtls/rsa.h b/ext/mbedtls-asn1/include/mbedtls/rsa.h
new file mode 100644
index 0000000..cffbe3b
--- /dev/null
+++ b/ext/mbedtls-asn1/include/mbedtls/rsa.h
@@ -0,0 +1,1119 @@
+/**
+ * \file rsa.h
+ *
+ * \brief This file provides an API for the RSA public-key cryptosystem.
+ *
+ * The RSA public-key cryptosystem is defined in <em>Public-Key
+ * Cryptography Standards (PKCS) #1 v1.5: RSA Encryption</em>
+ * and <em>Public-Key Cryptography Standards (PKCS) #1 v2.1:
+ * RSA Cryptography Specifications</em>.
+ *
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+#ifndef MBEDTLS_RSA_H
+#define MBEDTLS_RSA_H
+#include "mbedtls/private_access.h"
+
+#include "mbedtls/build_info.h"
+
+#include "mbedtls/bignum.h"
+#include "mbedtls/md.h"
+
+#if defined(MBEDTLS_THREADING_C)
+#include "mbedtls/threading.h"
+#endif
+
+/*
+ * RSA Error codes
+ */
+#define MBEDTLS_ERR_RSA_BAD_INPUT_DATA                    -0x4080  /**< Bad input parameters to function. */
+#define MBEDTLS_ERR_RSA_INVALID_PADDING                   -0x4100  /**< Input data contains invalid padding and is rejected. */
+#define MBEDTLS_ERR_RSA_KEY_GEN_FAILED                    -0x4180  /**< Something failed during generation of a key. */
+#define MBEDTLS_ERR_RSA_KEY_CHECK_FAILED                  -0x4200  /**< Key failed to pass the validity check of the library. */
+#define MBEDTLS_ERR_RSA_PUBLIC_FAILED                     -0x4280  /**< The public key operation failed. */
+#define MBEDTLS_ERR_RSA_PRIVATE_FAILED                    -0x4300  /**< The private key operation failed. */
+#define MBEDTLS_ERR_RSA_VERIFY_FAILED                     -0x4380  /**< The PKCS#1 verification failed. */
+#define MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE                  -0x4400  /**< The output buffer for decryption is not large enough. */
+#define MBEDTLS_ERR_RSA_RNG_FAILED                        -0x4480  /**< The random generator failed to generate non-zeros. */
+
+/*
+ * RSA constants
+ */
+
+#define MBEDTLS_RSA_PKCS_V15    0 /**< Use PKCS#1 v1.5 encoding. */
+#define MBEDTLS_RSA_PKCS_V21    1 /**< Use PKCS#1 v2.1 encoding. */
+
+#define MBEDTLS_RSA_SIGN        1 /**< Identifier for RSA signature operations. */
+#define MBEDTLS_RSA_CRYPT       2 /**< Identifier for RSA encryption and decryption operations. */
+
+#define MBEDTLS_RSA_SALT_LEN_ANY    -1
+
+/*
+ * The above constants may be used even if the RSA module is compile out,
+ * eg for alternative (PKCS#11) RSA implemenations in the PK layers.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if !defined(MBEDTLS_RSA_ALT)
+// Regular implementation
+//
+
+/**
+ * \brief   The RSA context structure.
+ */
+typedef struct mbedtls_rsa_context
+{
+    int MBEDTLS_PRIVATE(ver);                    /*!<  Reserved for internal purposes.
+                                 *    Do not set this field in application
+                                 *    code. Its meaning might change without
+                                 *    notice. */
+    size_t MBEDTLS_PRIVATE(len);                 /*!<  The size of \p N in Bytes. */
+
+    mbedtls_mpi MBEDTLS_PRIVATE(N);              /*!<  The public modulus. */
+    mbedtls_mpi MBEDTLS_PRIVATE(E);              /*!<  The public exponent. */
+
+    mbedtls_mpi MBEDTLS_PRIVATE(D);              /*!<  The private exponent. */
+    mbedtls_mpi MBEDTLS_PRIVATE(P);              /*!<  The first prime factor. */
+    mbedtls_mpi MBEDTLS_PRIVATE(Q);              /*!<  The second prime factor. */
+
+    mbedtls_mpi MBEDTLS_PRIVATE(DP);             /*!<  <code>D % (P - 1)</code>. */
+    mbedtls_mpi MBEDTLS_PRIVATE(DQ);             /*!<  <code>D % (Q - 1)</code>. */
+    mbedtls_mpi MBEDTLS_PRIVATE(QP);             /*!<  <code>1 / (Q % P)</code>. */
+
+    mbedtls_mpi MBEDTLS_PRIVATE(RN);             /*!<  cached <code>R^2 mod N</code>. */
+
+    mbedtls_mpi MBEDTLS_PRIVATE(RP);             /*!<  cached <code>R^2 mod P</code>. */
+    mbedtls_mpi MBEDTLS_PRIVATE(RQ);             /*!<  cached <code>R^2 mod Q</code>. */
+
+    mbedtls_mpi MBEDTLS_PRIVATE(Vi);             /*!<  The cached blinding value. */
+    mbedtls_mpi MBEDTLS_PRIVATE(Vf);             /*!<  The cached un-blinding value. */
+
+    int MBEDTLS_PRIVATE(padding);                /*!< Selects padding mode:
+                                     #MBEDTLS_RSA_PKCS_V15 for 1.5 padding and
+                                     #MBEDTLS_RSA_PKCS_V21 for OAEP or PSS. */
+    int MBEDTLS_PRIVATE(hash_id);                /*!< Hash identifier of mbedtls_md_type_t type,
+                                     as specified in md.h for use in the MGF
+                                     mask generating function used in the
+                                     EME-OAEP and EMSA-PSS encodings. */
+#if defined(MBEDTLS_THREADING_C)
+    /* Invariant: the mutex is initialized iff ver != 0. */
+    mbedtls_threading_mutex_t MBEDTLS_PRIVATE(mutex);    /*!<  Thread-safety mutex. */
+#endif
+}
+mbedtls_rsa_context;
+
+#else  /* MBEDTLS_RSA_ALT */
+#include "rsa_alt.h"
+#endif /* MBEDTLS_RSA_ALT */
+
+/**
+ * \brief          This function initializes an RSA context.
+ *
+ * \note           This function initializes the padding and the hash
+ *                 identifier to respectively #MBEDTLS_RSA_PKCS_V15 and
+ *                 #MBEDTLS_MD_NONE. See mbedtls_rsa_set_padding() for more
+ *                 information about those parameters.
+ *
+ * \param ctx      The RSA context to initialize. This must not be \c NULL.
+ */
+void mbedtls_rsa_init( mbedtls_rsa_context *ctx );
+
+/**
+ * \brief          This function sets padding for an already initialized RSA
+ *                 context.
+ *
+ * \note           Set padding to #MBEDTLS_RSA_PKCS_V21 for the RSAES-OAEP
+ *                 encryption scheme and the RSASSA-PSS signature scheme.
+ *
+ * \note           The \p hash_id parameter is ignored when using
+ *                 #MBEDTLS_RSA_PKCS_V15 padding.
+ *
+ * \note           The choice of padding mode is strictly enforced for private
+ *                 key operations, since there might be security concerns in
+ *                 mixing padding modes. For public key operations it is
+ *                 a default value, which can be overridden by calling specific
+ *                 \c mbedtls_rsa_rsaes_xxx or \c mbedtls_rsa_rsassa_xxx
+ *                 functions.
+ *
+ * \note           The hash selected in \p hash_id is always used for OEAP
+ *                 encryption. For PSS signatures, it is always used for
+ *                 making signatures, but can be overridden for verifying them.
+ *                 If set to #MBEDTLS_MD_NONE, it is always overridden.
+ *
+ * \param ctx      The initialized RSA context to be configured.
+ * \param padding  The padding mode to use. This must be either
+ *                 #MBEDTLS_RSA_PKCS_V15 or #MBEDTLS_RSA_PKCS_V21.
+ * \param hash_id  The hash identifier for PSS or OAEP, if \p padding is
+ *                 #MBEDTLS_RSA_PKCS_V21. #MBEDTLS_MD_NONE is accepted by this
+ *                 function but may be not suitable for some operations.
+ *                 Ignored if \p padding is #MBEDTLS_RSA_PKCS_V15.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_RSA_INVALID_PADDING failure:
+ *                 \p padding or \p hash_id is invalid.
+ */
+int mbedtls_rsa_set_padding( mbedtls_rsa_context *ctx, int padding,
+                             mbedtls_md_type_t hash_id );
+
+/**
+ * \brief          This function imports a set of core parameters into an
+ *                 RSA context.
+ *
+ * \note           This function can be called multiple times for successive
+ *                 imports, if the parameters are not simultaneously present.
+ *
+ *                 Any sequence of calls to this function should be followed
+ *                 by a call to mbedtls_rsa_complete(), which checks and
+ *                 completes the provided information to a ready-for-use
+ *                 public or private RSA key.
+ *
+ * \note           See mbedtls_rsa_complete() for more information on which
+ *                 parameters are necessary to set up a private or public
+ *                 RSA key.
+ *
+ * \note           The imported parameters are copied and need not be preserved
+ *                 for the lifetime of the RSA context being set up.
+ *
+ * \param ctx      The initialized RSA context to store the parameters in.
+ * \param N        The RSA modulus. This may be \c NULL.
+ * \param P        The first prime factor of \p N. This may be \c NULL.
+ * \param Q        The second prime factor of \p N. This may be \c NULL.
+ * \param D        The private exponent. This may be \c NULL.
+ * \param E        The public exponent. This may be \c NULL.
+ *
+ * \return         \c 0 on success.
+ * \return         A non-zero error code on failure.
+ */
+int mbedtls_rsa_import( mbedtls_rsa_context *ctx,
+                        const mbedtls_mpi *N,
+                        const mbedtls_mpi *P, const mbedtls_mpi *Q,
+                        const mbedtls_mpi *D, const mbedtls_mpi *E );
+
+/**
+ * \brief          This function imports core RSA parameters, in raw big-endian
+ *                 binary format, into an RSA context.
+ *
+ * \note           This function can be called multiple times for successive
+ *                 imports, if the parameters are not simultaneously present.
+ *
+ *                 Any sequence of calls to this function should be followed
+ *                 by a call to mbedtls_rsa_complete(), which checks and
+ *                 completes the provided information to a ready-for-use
+ *                 public or private RSA key.
+ *
+ * \note           See mbedtls_rsa_complete() for more information on which
+ *                 parameters are necessary to set up a private or public
+ *                 RSA key.
+ *
+ * \note           The imported parameters are copied and need not be preserved
+ *                 for the lifetime of the RSA context being set up.
+ *
+ * \param ctx      The initialized RSA context to store the parameters in.
+ * \param N        The RSA modulus. This may be \c NULL.
+ * \param N_len    The Byte length of \p N; it is ignored if \p N == NULL.
+ * \param P        The first prime factor of \p N. This may be \c NULL.
+ * \param P_len    The Byte length of \p P; it ns ignored if \p P == NULL.
+ * \param Q        The second prime factor of \p N. This may be \c NULL.
+ * \param Q_len    The Byte length of \p Q; it is ignored if \p Q == NULL.
+ * \param D        The private exponent. This may be \c NULL.
+ * \param D_len    The Byte length of \p D; it is ignored if \p D == NULL.
+ * \param E        The public exponent. This may be \c NULL.
+ * \param E_len    The Byte length of \p E; it is ignored if \p E == NULL.
+ *
+ * \return         \c 0 on success.
+ * \return         A non-zero error code on failure.
+ */
+int mbedtls_rsa_import_raw( mbedtls_rsa_context *ctx,
+                            unsigned char const *N, size_t N_len,
+                            unsigned char const *P, size_t P_len,
+                            unsigned char const *Q, size_t Q_len,
+                            unsigned char const *D, size_t D_len,
+                            unsigned char const *E, size_t E_len );
+
+/**
+ * \brief          This function completes an RSA context from
+ *                 a set of imported core parameters.
+ *
+ *                 To setup an RSA public key, precisely \p N and \p E
+ *                 must have been imported.
+ *
+ *                 To setup an RSA private key, sufficient information must
+ *                 be present for the other parameters to be derivable.
+ *
+ *                 The default implementation supports the following:
+ *                 <ul><li>Derive \p P, \p Q from \p N, \p D, \p E.</li>
+ *                 <li>Derive \p N, \p D from \p P, \p Q, \p E.</li></ul>
+ *                 Alternative implementations need not support these.
+ *
+ *                 If this function runs successfully, it guarantees that
+ *                 the RSA context can be used for RSA operations without
+ *                 the risk of failure or crash.
+ *
+ * \warning        This function need not perform consistency checks
+ *                 for the imported parameters. In particular, parameters that
+ *                 are not needed by the implementation might be silently
+ *                 discarded and left unchecked. To check the consistency
+ *                 of the key material, see mbedtls_rsa_check_privkey().
+ *
+ * \param ctx      The initialized RSA context holding imported parameters.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_RSA_BAD_INPUT_DATA if the attempted derivations
+ *                 failed.
+ *
+ */
+int mbedtls_rsa_complete( mbedtls_rsa_context *ctx );
+
+/**
+ * \brief          This function exports the core parameters of an RSA key.
+ *
+ *                 If this function runs successfully, the non-NULL buffers
+ *                 pointed to by \p N, \p P, \p Q, \p D, and \p E are fully
+ *                 written, with additional unused space filled leading by
+ *                 zero Bytes.
+ *
+ *                 Possible reasons for returning
+ *                 #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED:<ul>
+ *                 <li>An alternative RSA implementation is in use, which
+ *                 stores the key externally, and either cannot or should
+ *                 not export it into RAM.</li>
+ *                 <li>A SW or HW implementation might not support a certain
+ *                 deduction. For example, \p P, \p Q from \p N, \p D,
+ *                 and \p E if the former are not part of the
+ *                 implementation.</li></ul>
+ *
+ *                 If the function fails due to an unsupported operation,
+ *                 the RSA context stays intact and remains usable.
+ *
+ * \param ctx      The initialized RSA context.
+ * \param N        The MPI to hold the RSA modulus.
+ *                 This may be \c NULL if this field need not be exported.
+ * \param P        The MPI to hold the first prime factor of \p N.
+ *                 This may be \c NULL if this field need not be exported.
+ * \param Q        The MPI to hold the second prime factor of \p N.
+ *                 This may be \c NULL if this field need not be exported.
+ * \param D        The MPI to hold the private exponent.
+ *                 This may be \c NULL if this field need not be exported.
+ * \param E        The MPI to hold the public exponent.
+ *                 This may be \c NULL if this field need not be exported.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED if exporting the
+ *                 requested parameters cannot be done due to missing
+ *                 functionality or because of security policies.
+ * \return         A non-zero return code on any other failure.
+ *
+ */
+int mbedtls_rsa_export( const mbedtls_rsa_context *ctx,
+                        mbedtls_mpi *N, mbedtls_mpi *P, mbedtls_mpi *Q,
+                        mbedtls_mpi *D, mbedtls_mpi *E );
+
+/**
+ * \brief          This function exports core parameters of an RSA key
+ *                 in raw big-endian binary format.
+ *
+ *                 If this function runs successfully, the non-NULL buffers
+ *                 pointed to by \p N, \p P, \p Q, \p D, and \p E are fully
+ *                 written, with additional unused space filled leading by
+ *                 zero Bytes.
+ *
+ *                 Possible reasons for returning
+ *                 #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED:<ul>
+ *                 <li>An alternative RSA implementation is in use, which
+ *                 stores the key externally, and either cannot or should
+ *                 not export it into RAM.</li>
+ *                 <li>A SW or HW implementation might not support a certain
+ *                 deduction. For example, \p P, \p Q from \p N, \p D,
+ *                 and \p E if the former are not part of the
+ *                 implementation.</li></ul>
+ *                 If the function fails due to an unsupported operation,
+ *                 the RSA context stays intact and remains usable.
+ *
+ * \note           The length parameters are ignored if the corresponding
+ *                 buffer pointers are NULL.
+ *
+ * \param ctx      The initialized RSA context.
+ * \param N        The Byte array to store the RSA modulus,
+ *                 or \c NULL if this field need not be exported.
+ * \param N_len    The size of the buffer for the modulus.
+ * \param P        The Byte array to hold the first prime factor of \p N,
+ *                 or \c NULL if this field need not be exported.
+ * \param P_len    The size of the buffer for the first prime factor.
+ * \param Q        The Byte array to hold the second prime factor of \p N,
+ *                 or \c NULL if this field need not be exported.
+ * \param Q_len    The size of the buffer for the second prime factor.
+ * \param D        The Byte array to hold the private exponent,
+ *                 or \c NULL if this field need not be exported.
+ * \param D_len    The size of the buffer for the private exponent.
+ * \param E        The Byte array to hold the public exponent,
+ *                 or \c NULL if this field need not be exported.
+ * \param E_len    The size of the buffer for the public exponent.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED if exporting the
+ *                 requested parameters cannot be done due to missing
+ *                 functionality or because of security policies.
+ * \return         A non-zero return code on any other failure.
+ */
+int mbedtls_rsa_export_raw( const mbedtls_rsa_context *ctx,
+                            unsigned char *N, size_t N_len,
+                            unsigned char *P, size_t P_len,
+                            unsigned char *Q, size_t Q_len,
+                            unsigned char *D, size_t D_len,
+                            unsigned char *E, size_t E_len );
+
+/**
+ * \brief          This function exports CRT parameters of a private RSA key.
+ *
+ * \note           Alternative RSA implementations not using CRT-parameters
+ *                 internally can implement this function based on
+ *                 mbedtls_rsa_deduce_opt().
+ *
+ * \param ctx      The initialized RSA context.
+ * \param DP       The MPI to hold \c D modulo `P-1`,
+ *                 or \c NULL if it need not be exported.
+ * \param DQ       The MPI to hold \c D modulo `Q-1`,
+ *                 or \c NULL if it need not be exported.
+ * \param QP       The MPI to hold modular inverse of \c Q modulo \c P,
+ *                 or \c NULL if it need not be exported.
+ *
+ * \return         \c 0 on success.
+ * \return         A non-zero error code on failure.
+ *
+ */
+int mbedtls_rsa_export_crt( const mbedtls_rsa_context *ctx,
+                            mbedtls_mpi *DP, mbedtls_mpi *DQ, mbedtls_mpi *QP );
+
+/**
+ * \brief          This function retrieves the length of RSA modulus in Bytes.
+ *
+ * \param ctx      The initialized RSA context.
+ *
+ * \return         The length of the RSA modulus in Bytes.
+ *
+ */
+size_t mbedtls_rsa_get_len( const mbedtls_rsa_context *ctx );
+
+/**
+ * \brief          This function generates an RSA keypair.
+ *
+ * \note           mbedtls_rsa_init() must be called before this function,
+ *                 to set up the RSA context.
+ *
+ * \param ctx      The initialized RSA context used to hold the key.
+ * \param f_rng    The RNG function to be used for key generation.
+ *                 This is mandatory and must not be \c NULL.
+ * \param p_rng    The RNG context to be passed to \p f_rng.
+ *                 This may be \c NULL if \p f_rng doesn't need a context.
+ * \param nbits    The size of the public key in bits.
+ * \param exponent The public exponent to use. For example, \c 65537.
+ *                 This must be odd and greater than \c 1.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_gen_key( mbedtls_rsa_context *ctx,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng,
+                         unsigned int nbits, int exponent );
+
+/**
+ * \brief          This function checks if a context contains at least an RSA
+ *                 public key.
+ *
+ *                 If the function runs successfully, it is guaranteed that
+ *                 enough information is present to perform an RSA public key
+ *                 operation using mbedtls_rsa_public().
+ *
+ * \param ctx      The initialized RSA context to check.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ *
+ */
+int mbedtls_rsa_check_pubkey( const mbedtls_rsa_context *ctx );
+
+/**
+ * \brief      This function checks if a context contains an RSA private key
+ *             and perform basic consistency checks.
+ *
+ * \note       The consistency checks performed by this function not only
+ *             ensure that mbedtls_rsa_private() can be called successfully
+ *             on the given context, but that the various parameters are
+ *             mutually consistent with high probability, in the sense that
+ *             mbedtls_rsa_public() and mbedtls_rsa_private() are inverses.
+ *
+ * \warning    This function should catch accidental misconfigurations
+ *             like swapping of parameters, but it cannot establish full
+ *             trust in neither the quality nor the consistency of the key
+ *             material that was used to setup the given RSA context:
+ *             <ul><li>Consistency: Imported parameters that are irrelevant
+ *             for the implementation might be silently dropped. If dropped,
+ *             the current function does not have access to them,
+ *             and therefore cannot check them. See mbedtls_rsa_complete().
+ *             If you want to check the consistency of the entire
+ *             content of an PKCS1-encoded RSA private key, for example, you
+ *             should use mbedtls_rsa_validate_params() before setting
+ *             up the RSA context.
+ *             Additionally, if the implementation performs empirical checks,
+ *             these checks substantiate but do not guarantee consistency.</li>
+ *             <li>Quality: This function is not expected to perform
+ *             extended quality assessments like checking that the prime
+ *             factors are safe. Additionally, it is the responsibility of the
+ *             user to ensure the trustworthiness of the source of his RSA
+ *             parameters, which goes beyond what is effectively checkable
+ *             by the library.</li></ul>
+ *
+ * \param ctx  The initialized RSA context to check.
+ *
+ * \return     \c 0 on success.
+ * \return     An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_check_privkey( const mbedtls_rsa_context *ctx );
+
+/**
+ * \brief          This function checks a public-private RSA key pair.
+ *
+ *                 It checks each of the contexts, and makes sure they match.
+ *
+ * \param pub      The initialized RSA context holding the public key.
+ * \param prv      The initialized RSA context holding the private key.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_check_pub_priv( const mbedtls_rsa_context *pub,
+                                const mbedtls_rsa_context *prv );
+
+/**
+ * \brief          This function performs an RSA public key operation.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param input    The input buffer. This must be a readable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ * \param output   The output buffer. This must be a writable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \note           This function does not handle message padding.
+ *
+ * \note           Make sure to set \p input[0] = 0 or ensure that
+ *                 input is smaller than \p N.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_public( mbedtls_rsa_context *ctx,
+                const unsigned char *input,
+                unsigned char *output );
+
+/**
+ * \brief          This function performs an RSA private key operation.
+ *
+ * \note           Blinding is used if and only if a PRNG is provided.
+ *
+ * \note           If blinding is used, both the base of exponentation
+ *                 and the exponent are blinded, providing protection
+ *                 against some side-channel attacks.
+ *
+ * \warning        It is deprecated and a security risk to not provide
+ *                 a PRNG here and thereby prevent the use of blinding.
+ *                 Future versions of the library may enforce the presence
+ *                 of a PRNG.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function, used for blinding. It is mandatory.
+ * \param p_rng    The RNG context to pass to \p f_rng. This may be \c NULL
+ *                 if \p f_rng doesn't need a context.
+ * \param input    The input buffer. This must be a readable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ * \param output   The output buffer. This must be a writable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ *
+ */
+int mbedtls_rsa_private( mbedtls_rsa_context *ctx,
+                 int (*f_rng)(void *, unsigned char *, size_t),
+                 void *p_rng,
+                 const unsigned char *input,
+                 unsigned char *output );
+
+/**
+ * \brief          This function adds the message padding, then performs an RSA
+ *                 operation.
+ *
+ *                 It is the generic wrapper for performing a PKCS#1 encryption
+ *                 operation.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG to use. It is used for padding generation
+ *                 and it is mandatory.
+ * \param p_rng    The RNG context to be passed to \p f_rng. May be
+ *                 \c NULL if \p f_rng doesn't need a context argument.
+ * \param ilen     The length of the plaintext in Bytes.
+ * \param input    The input data to encrypt. This must be a readable
+ *                 buffer of size \p ilen Bytes. It may be \c NULL if
+ *                 `ilen == 0`.
+ * \param output   The output buffer. This must be a writable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_pkcs1_encrypt( mbedtls_rsa_context *ctx,
+                       int (*f_rng)(void *, unsigned char *, size_t),
+                       void *p_rng,
+                       size_t ilen,
+                       const unsigned char *input,
+                       unsigned char *output );
+
+/**
+ * \brief          This function performs a PKCS#1 v1.5 encryption operation
+ *                 (RSAES-PKCS1-v1_5-ENCRYPT).
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function to use. It is mandatory and used for
+ *                 padding generation.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may
+ *                 be \c NULL if \p f_rng doesn't need a context argument.
+ * \param ilen     The length of the plaintext in Bytes.
+ * \param input    The input data to encrypt. This must be a readable
+ *                 buffer of size \p ilen Bytes. It may be \c NULL if
+ *                 `ilen == 0`.
+ * \param output   The output buffer. This must be a writable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx,
+                                 int (*f_rng)(void *, unsigned char *, size_t),
+                                 void *p_rng,
+                                 size_t ilen,
+                                 const unsigned char *input,
+                                 unsigned char *output );
+
+/**
+ * \brief            This function performs a PKCS#1 v2.1 OAEP encryption
+ *                   operation (RSAES-OAEP-ENCRYPT).
+ *
+ * \note             The output buffer must be as large as the size
+ *                   of ctx->N. For example, 128 Bytes if RSA-1024 is used.
+ *
+ * \param ctx        The initnialized RSA context to use.
+ * \param f_rng      The RNG function to use. This is needed for padding
+ *                   generation and is mandatory.
+ * \param p_rng      The RNG context to be passed to \p f_rng. This may
+ *                   be \c NULL if \p f_rng doesn't need a context argument.
+ * \param label      The buffer holding the custom label to use.
+ *                   This must be a readable buffer of length \p label_len
+ *                   Bytes. It may be \c NULL if \p label_len is \c 0.
+ * \param label_len  The length of the label in Bytes.
+ * \param ilen       The length of the plaintext buffer \p input in Bytes.
+ * \param input      The input data to encrypt. This must be a readable
+ *                   buffer of size \p ilen Bytes. It may be \c NULL if
+ *                   `ilen == 0`.
+ * \param output     The output buffer. This must be a writable buffer
+ *                   of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                   for an 2048-bit RSA modulus.
+ *
+ * \return           \c 0 on success.
+ * \return           An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsaes_oaep_encrypt( mbedtls_rsa_context *ctx,
+                            int (*f_rng)(void *, unsigned char *, size_t),
+                            void *p_rng,
+                            const unsigned char *label, size_t label_len,
+                            size_t ilen,
+                            const unsigned char *input,
+                            unsigned char *output );
+
+/**
+ * \brief          This function performs an RSA operation, then removes the
+ *                 message padding.
+ *
+ *                 It is the generic wrapper for performing a PKCS#1 decryption
+ *                 operation.
+ *
+ * \note           The output buffer length \c output_max_len should be
+ *                 as large as the size \p ctx->len of \p ctx->N (for example,
+ *                 128 Bytes if RSA-1024 is used) to be able to hold an
+ *                 arbitrary decrypted message. If it is not large enough to
+ *                 hold the decryption of the particular ciphertext provided,
+ *                 the function returns \c MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function. This is used for blinding and is
+ *                 mandatory; see mbedtls_rsa_private() for more.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be
+ *                 \c NULL if \p f_rng doesn't need a context.
+ * \param olen     The address at which to store the length of
+ *                 the plaintext. This must not be \c NULL.
+ * \param input    The ciphertext buffer. This must be a readable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ * \param output   The buffer used to hold the plaintext. This must
+ *                 be a writable buffer of length \p output_max_len Bytes.
+ * \param output_max_len The length in Bytes of the output buffer \p output.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_pkcs1_decrypt( mbedtls_rsa_context *ctx,
+                       int (*f_rng)(void *, unsigned char *, size_t),
+                       void *p_rng,
+                       size_t *olen,
+                       const unsigned char *input,
+                       unsigned char *output,
+                       size_t output_max_len );
+
+/**
+ * \brief          This function performs a PKCS#1 v1.5 decryption
+ *                 operation (RSAES-PKCS1-v1_5-DECRYPT).
+ *
+ * \note           The output buffer length \c output_max_len should be
+ *                 as large as the size \p ctx->len of \p ctx->N, for example,
+ *                 128 Bytes if RSA-1024 is used, to be able to hold an
+ *                 arbitrary decrypted message. If it is not large enough to
+ *                 hold the decryption of the particular ciphertext provided,
+ *                 the function returns #MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function. This is used for blinding and is
+ *                 mandatory; see mbedtls_rsa_private() for more.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be
+ *                 \c NULL if \p f_rng doesn't need a context.
+ * \param olen     The address at which to store the length of
+ *                 the plaintext. This must not be \c NULL.
+ * \param input    The ciphertext buffer. This must be a readable buffer
+ *                 of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ * \param output   The buffer used to hold the plaintext. This must
+ *                 be a writable buffer of length \p output_max_len Bytes.
+ * \param output_max_len The length in Bytes of the output buffer \p output.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ *
+ */
+int mbedtls_rsa_rsaes_pkcs1_v15_decrypt( mbedtls_rsa_context *ctx,
+                                 int (*f_rng)(void *, unsigned char *, size_t),
+                                 void *p_rng,
+                                 size_t *olen,
+                                 const unsigned char *input,
+                                 unsigned char *output,
+                                 size_t output_max_len );
+
+/**
+ * \brief            This function performs a PKCS#1 v2.1 OAEP decryption
+ *                   operation (RSAES-OAEP-DECRYPT).
+ *
+ * \note             The output buffer length \c output_max_len should be
+ *                   as large as the size \p ctx->len of \p ctx->N, for
+ *                   example, 128 Bytes if RSA-1024 is used, to be able to
+ *                   hold an arbitrary decrypted message. If it is not
+ *                   large enough to hold the decryption of the particular
+ *                   ciphertext provided, the function returns
+ *                   #MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.
+ *
+ * \param ctx        The initialized RSA context to use.
+ * \param f_rng      The RNG function. This is used for blinding and is
+ *                   mandatory.
+ * \param p_rng      The RNG context to be passed to \p f_rng. This may be
+ *                   \c NULL if \p f_rng doesn't need a context.
+ * \param label      The buffer holding the custom label to use.
+ *                   This must be a readable buffer of length \p label_len
+ *                   Bytes. It may be \c NULL if \p label_len is \c 0.
+ * \param label_len  The length of the label in Bytes.
+ * \param olen       The address at which to store the length of
+ *                   the plaintext. This must not be \c NULL.
+ * \param input      The ciphertext buffer. This must be a readable buffer
+ *                   of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                   for an 2048-bit RSA modulus.
+ * \param output     The buffer used to hold the plaintext. This must
+ *                   be a writable buffer of length \p output_max_len Bytes.
+ * \param output_max_len The length in Bytes of the output buffer \p output.
+ *
+ * \return         \c 0 on success.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsaes_oaep_decrypt( mbedtls_rsa_context *ctx,
+                            int (*f_rng)(void *, unsigned char *, size_t),
+                            void *p_rng,
+                            const unsigned char *label, size_t label_len,
+                            size_t *olen,
+                            const unsigned char *input,
+                            unsigned char *output,
+                            size_t output_max_len );
+
+/**
+ * \brief          This function performs a private RSA operation to sign
+ *                 a message digest using PKCS#1.
+ *
+ *                 It is the generic wrapper for performing a PKCS#1
+ *                 signature.
+ *
+ * \note           The \p sig buffer must be as large as the size
+ *                 of \p ctx->N. For example, 128 Bytes if RSA-1024 is used.
+ *
+ * \note           For PKCS#1 v2.1 encoding, see comments on
+ *                 mbedtls_rsa_rsassa_pss_sign() for details on
+ *                 \p md_alg and \p hash_id.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function to use. This is mandatory and
+ *                 must not be \c NULL.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be \c NULL
+ *                 if \p f_rng doesn't need a context argument.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param sig      The buffer to hold the signature. This must be a writable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus. A buffer length of
+ *                 #MBEDTLS_MPI_MAX_SIZE is always safe.
+ *
+ * \return         \c 0 if the signing operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_pkcs1_sign( mbedtls_rsa_context *ctx,
+                    int (*f_rng)(void *, unsigned char *, size_t),
+                    void *p_rng,
+                    mbedtls_md_type_t md_alg,
+                    unsigned int hashlen,
+                    const unsigned char *hash,
+                    unsigned char *sig );
+
+/**
+ * \brief          This function performs a PKCS#1 v1.5 signature
+ *                 operation (RSASSA-PKCS1-v1_5-SIGN).
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function. This is used for blinding and is
+ *                 mandatory; see mbedtls_rsa_private() for more.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be \c NULL
+ *                 if \p f_rng doesn't need a context argument.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param sig      The buffer to hold the signature. This must be a writable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus. A buffer length of
+ *                 #MBEDTLS_MPI_MAX_SIZE is always safe.
+ *
+ * \return         \c 0 if the signing operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsassa_pkcs1_v15_sign( mbedtls_rsa_context *ctx,
+                               int (*f_rng)(void *, unsigned char *, size_t),
+                               void *p_rng,
+                               mbedtls_md_type_t md_alg,
+                               unsigned int hashlen,
+                               const unsigned char *hash,
+                               unsigned char *sig );
+
+/**
+ * \brief          This function performs a PKCS#1 v2.1 PSS signature
+ *                 operation (RSASSA-PSS-SIGN).
+ *
+ * \note           The \c hash_id set in \p ctx by calling
+ *                 mbedtls_rsa_set_padding() selects the hash used for the
+ *                 encoding operation and for the mask generation function
+ *                 (MGF1). For more details on the encoding operation and the
+ *                 mask generation function, consult <em>RFC-3447: Public-Key
+ *                 Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography
+ *                 Specifications</em>.
+ *
+ * \note           This function enforces that the provided salt length complies
+ *                 with FIPS 186-4 §5.5 (e) and RFC 8017 (PKCS#1 v2.2) §9.1.1
+ *                 step 3. The constraint is that the hash length plus the salt
+ *                 length plus 2 bytes must be at most the key length. If this
+ *                 constraint is not met, this function returns
+ *                 #MBEDTLS_ERR_RSA_BAD_INPUT_DATA.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function. It is mandatory and must not be \c NULL.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be \c NULL
+ *                 if \p f_rng doesn't need a context argument.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param saltlen  The length of the salt that should be used.
+ *                 If passed #MBEDTLS_RSA_SALT_LEN_ANY, the function will use
+ *                 the largest possible salt length up to the hash length,
+ *                 which is the largest permitted by some standards including
+ *                 FIPS 186-4 §5.5.
+ * \param sig      The buffer to hold the signature. This must be a writable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus. A buffer length of
+ *                 #MBEDTLS_MPI_MAX_SIZE is always safe.
+ *
+ * \return         \c 0 if the signing operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsassa_pss_sign_ext( mbedtls_rsa_context *ctx,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng,
+                         mbedtls_md_type_t md_alg,
+                         unsigned int hashlen,
+                         const unsigned char *hash,
+                         int saltlen,
+                         unsigned char *sig );
+
+/**
+ * \brief          This function performs a PKCS#1 v2.1 PSS signature
+ *                 operation (RSASSA-PSS-SIGN).
+ *
+ * \note           The \c hash_id set in \p ctx by calling
+ *                 mbedtls_rsa_set_padding() selects the hash used for the
+ *                 encoding operation and for the mask generation function
+ *                 (MGF1). For more details on the encoding operation and the
+ *                 mask generation function, consult <em>RFC-3447: Public-Key
+ *                 Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography
+ *                 Specifications</em>.
+ *
+ * \note           This function always uses the maximum possible salt size,
+ *                 up to the length of the payload hash. This choice of salt
+ *                 size complies with FIPS 186-4 §5.5 (e) and RFC 8017 (PKCS#1
+ *                 v2.2) §9.1.1 step 3. Furthermore this function enforces a
+ *                 minimum salt size which is the hash size minus 2 bytes. If
+ *                 this minimum size is too large given the key size (the salt
+ *                 size, plus the hash size, plus 2 bytes must be no more than
+ *                 the key size in bytes), this function returns
+ *                 #MBEDTLS_ERR_RSA_BAD_INPUT_DATA.
+ *
+ * \param ctx      The initialized RSA context to use.
+ * \param f_rng    The RNG function. It is mandatory and must not be \c NULL.
+ * \param p_rng    The RNG context to be passed to \p f_rng. This may be \c NULL
+ *                 if \p f_rng doesn't need a context argument.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param sig      The buffer to hold the signature. This must be a writable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus. A buffer length of
+ *                 #MBEDTLS_MPI_MAX_SIZE is always safe.
+ *
+ * \return         \c 0 if the signing operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsassa_pss_sign( mbedtls_rsa_context *ctx,
+                         int (*f_rng)(void *, unsigned char *, size_t),
+                         void *p_rng,
+                         mbedtls_md_type_t md_alg,
+                         unsigned int hashlen,
+                         const unsigned char *hash,
+                         unsigned char *sig );
+
+/**
+ * \brief          This function performs a public RSA operation and checks
+ *                 the message digest.
+ *
+ *                 This is the generic wrapper for performing a PKCS#1
+ *                 verification.
+ *
+ * \note           For PKCS#1 v2.1 encoding, see comments on
+ *                 mbedtls_rsa_rsassa_pss_verify() about \p md_alg and
+ *                 \p hash_id.
+ *
+ * \param ctx      The initialized RSA public key context to use.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param sig      The buffer holding the signature. This must be a readable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 if the verify operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_pkcs1_verify( mbedtls_rsa_context *ctx,
+                      mbedtls_md_type_t md_alg,
+                      unsigned int hashlen,
+                      const unsigned char *hash,
+                      const unsigned char *sig );
+
+/**
+ * \brief          This function performs a PKCS#1 v1.5 verification
+ *                 operation (RSASSA-PKCS1-v1_5-VERIFY).
+ *
+ * \param ctx      The initialized RSA public key context to use.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param sig      The buffer holding the signature. This must be a readable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 if the verify operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsassa_pkcs1_v15_verify( mbedtls_rsa_context *ctx,
+                                 mbedtls_md_type_t md_alg,
+                                 unsigned int hashlen,
+                                 const unsigned char *hash,
+                                 const unsigned char *sig );
+
+/**
+ * \brief          This function performs a PKCS#1 v2.1 PSS verification
+ *                 operation (RSASSA-PSS-VERIFY).
+ *
+ * \note           The \c hash_id set in \p ctx by calling
+ *                 mbedtls_rsa_set_padding() selects the hash used for the
+ *                 encoding operation and for the mask generation function
+ *                 (MGF1). For more details on the encoding operation and the
+ *                 mask generation function, consult <em>RFC-3447: Public-Key
+ *                 Cryptography Standards (PKCS) #1 v2.1: RSA Cryptography
+ *                 Specifications</em>. If the \c hash_id set in \p ctx by
+ *                 mbedtls_rsa_set_padding() is #MBEDTLS_MD_NONE, the \p md_alg
+ *                 parameter is used.
+ *
+ * \param ctx      The initialized RSA public key context to use.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param sig      The buffer holding the signature. This must be a readable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 if the verify operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsassa_pss_verify( mbedtls_rsa_context *ctx,
+                           mbedtls_md_type_t md_alg,
+                           unsigned int hashlen,
+                           const unsigned char *hash,
+                           const unsigned char *sig );
+
+/**
+ * \brief          This function performs a PKCS#1 v2.1 PSS verification
+ *                 operation (RSASSA-PSS-VERIFY).
+ *
+ * \note           The \p sig buffer must be as large as the size
+ *                 of \p ctx->N. For example, 128 Bytes if RSA-1024 is used.
+ *
+ * \note           The \c hash_id set in \p ctx by mbedtls_rsa_set_padding() is
+ *                 ignored.
+ *
+ * \param ctx      The initialized RSA public key context to use.
+ * \param md_alg   The message-digest algorithm used to hash the original data.
+ *                 Use #MBEDTLS_MD_NONE for signing raw data.
+ * \param hashlen  The length of the message digest or raw data in Bytes.
+ *                 If \p md_alg is not #MBEDTLS_MD_NONE, this must match the
+ *                 output length of the corresponding hash algorithm.
+ * \param hash     The buffer holding the message digest or raw data.
+ *                 This must be a readable buffer of at least \p hashlen Bytes.
+ * \param mgf1_hash_id      The message digest algorithm used for the
+ *                          verification operation and the mask generation
+ *                          function (MGF1). For more details on the encoding
+ *                          operation and the mask generation function, consult
+ *                          <em>RFC-3447: Public-Key Cryptography Standards
+ *                          (PKCS) #1 v2.1: RSA Cryptography
+ *                          Specifications</em>.
+ * \param expected_salt_len The length of the salt used in padding. Use
+ *                          #MBEDTLS_RSA_SALT_LEN_ANY to accept any salt length.
+ * \param sig      The buffer holding the signature. This must be a readable
+ *                 buffer of length \c ctx->len Bytes. For example, \c 256 Bytes
+ *                 for an 2048-bit RSA modulus.
+ *
+ * \return         \c 0 if the verify operation was successful.
+ * \return         An \c MBEDTLS_ERR_RSA_XXX error code on failure.
+ */
+int mbedtls_rsa_rsassa_pss_verify_ext( mbedtls_rsa_context *ctx,
+                               mbedtls_md_type_t md_alg,
+                               unsigned int hashlen,
+                               const unsigned char *hash,
+                               mbedtls_md_type_t mgf1_hash_id,
+                               int expected_salt_len,
+                               const unsigned char *sig );
+
+/**
+ * \brief          This function copies the components of an RSA context.
+ *
+ * \param dst      The destination context. This must be initialized.
+ * \param src      The source context. This must be initialized.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory allocation failure.
+ */
+int mbedtls_rsa_copy( mbedtls_rsa_context *dst, const mbedtls_rsa_context *src );
+
+/**
+ * \brief          This function frees the components of an RSA key.
+ *
+ * \param ctx      The RSA context to free. May be \c NULL, in which case
+ *                 this function is a no-op. If it is not \c NULL, it must
+ *                 point to an initialized RSA context.
+ */
+void mbedtls_rsa_free( mbedtls_rsa_context *ctx );
+
+#if defined(MBEDTLS_SELF_TEST)
+
+/**
+ * \brief          The RSA checkup routine.
+ *
+ * \return         \c 0 on success.
+ * \return         \c 1 on failure.
+ */
+int mbedtls_rsa_self_test( int verbose );
+
+#endif /* MBEDTLS_SELF_TEST */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* rsa.h */
diff --git a/ext/mbedtls-asn1/include/mbedtls/threading.h b/ext/mbedtls-asn1/include/mbedtls/threading.h
index 92e6e6b..96cadc4 100644
--- a/ext/mbedtls-asn1/include/mbedtls/threading.h
+++ b/ext/mbedtls-asn1/include/mbedtls/threading.h
@@ -4,7 +4,7 @@
  * \brief Threading abstraction layer
  */
 /*
- *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -18,17 +18,12 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 #ifndef MBEDTLS_THREADING_H
 #define MBEDTLS_THREADING_H
+#include "mbedtls/private_access.h"
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "mbedtls/build_info.h"
 
 #include <stdlib.h>
 
@@ -36,10 +31,6 @@
 extern "C" {
 #endif
 
-/* MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE is deprecated and should not be
- * used. */
-#define MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE         -0x001A  /**< The selected feature is not available. */
-
 #define MBEDTLS_ERR_THREADING_BAD_INPUT_DATA              -0x001C  /**< Bad input parameters to function. */
 #define MBEDTLS_ERR_THREADING_MUTEX_ERROR                 -0x001E  /**< Locking / unlocking / free failed with error code. */
 
@@ -47,8 +38,11 @@
 #include <pthread.h>
 typedef struct mbedtls_threading_mutex_t
 {
-    pthread_mutex_t mutex;
-    char is_valid;
+    pthread_mutex_t MBEDTLS_PRIVATE(mutex);
+    /* is_valid is 0 after a failed init or a free, and nonzero after a
+     * successful init. This field is not considered part of the public
+     * API of Mbed TLS and may change without notice. */
+    char MBEDTLS_PRIVATE(is_valid);
 } mbedtls_threading_mutex_t;
 #endif