diff --git a/include/polarssl/asn1.h b/include/polarssl/asn1.h
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+/**
+ * \file asn1.h
+ *
+ * \brief Generic ASN.1 parsing
+ *
+ *  Copyright (C) 2006-2011, Brainspark B.V.
+ *
+ *  This file is part of PolarSSL (http://www.polarssl.org)
+ *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ *  All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#ifndef POLARSSL_ASN1_H
+#define POLARSSL_ASN1_H
+
+#include "polarssl/config.h"
+
+#if defined(POLARSSL_BIGNUM_C)
+#include "polarssl/bignum.h"
+#endif
+
+#include <string.h>
+
+/** 
+ * \addtogroup asn1_module
+ * \{ 
+ */
+ 
+/**
+ * \name ASN1 Error codes
+ * These error codes are OR'ed to X509 error codes for
+ * higher error granularity. 
+ * ASN1 is a standard to specify data structures.
+ * \{
+ */
+#define POLARSSL_ERR_ASN1_OUT_OF_DATA                      -0x0014  /**< Out of data when parsing an ASN1 data structure. */
+#define POLARSSL_ERR_ASN1_UNEXPECTED_TAG                   -0x0016  /**< ASN1 tag was of an unexpected value. */
+#define POLARSSL_ERR_ASN1_INVALID_LENGTH                   -0x0018  /**< Error when trying to determine the length or invalid length. */
+#define POLARSSL_ERR_ASN1_LENGTH_MISMATCH                  -0x001A  /**< Actual length differs from expected length. */
+#define POLARSSL_ERR_ASN1_INVALID_DATA                     -0x001C  /**< Data is invalid. (not used) */
+/* \} name */
+
+/**
+ * \name DER constants
+ * These constants comply with DER encoded the ANS1 type tags.
+ * DER encoding uses hexadecimal representation.
+ * An example DER sequence is:\n
+ * - 0x02 -- tag indicating INTEGER
+ * - 0x01 -- length in octets
+ * - 0x05 -- value
+ * Such sequences are typically read into \c ::x509_buf.
+ * \{
+ */
+#define ASN1_BOOLEAN                 0x01
+#define ASN1_INTEGER                 0x02
+#define ASN1_BIT_STRING              0x03
+#define ASN1_OCTET_STRING            0x04
+#define ASN1_NULL                    0x05
+#define ASN1_OID                     0x06
+#define ASN1_UTF8_STRING             0x0C
+#define ASN1_SEQUENCE                0x10
+#define ASN1_SET                     0x11
+#define ASN1_PRINTABLE_STRING        0x13
+#define ASN1_T61_STRING              0x14
+#define ASN1_IA5_STRING              0x16
+#define ASN1_UTC_TIME                0x17
+#define ASN1_GENERALIZED_TIME        0x18
+#define ASN1_UNIVERSAL_STRING        0x1C
+#define ASN1_BMP_STRING              0x1E
+#define ASN1_PRIMITIVE               0x00
+#define ASN1_CONSTRUCTED             0x20
+#define ASN1_CONTEXT_SPECIFIC        0x80
+/* \} name */
+/* \} addtogroup asn1_module */
+
+/** Returns the size of the binary string, without the trailing \\0 */
+#define OID_SIZE(x) (sizeof(x) - 1)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \name Functions to parse ASN.1 data structures
+ * \{
+ */
+
+/**
+ * Type-length-value structure that allows for ASN1 using DER.
+ */
+typedef struct _asn1_buf
+{
+    int tag;                /**< ASN1 type, e.g. ASN1_UTF8_STRING. */
+    size_t len;             /**< ASN1 length, e.g. in octets. */
+    unsigned char *p;       /**< ASN1 data, e.g. in ASCII. */
+}
+asn1_buf;
+
+/**
+ * Container for ASN1 bit strings.
+ */
+typedef struct _asn1_bitstring
+{
+    size_t len;                 /**< ASN1 length, e.g. 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 */
+}
+asn1_bitstring;
+
+/**
+ * Container for a sequence of ASN.1 items
+ */
+typedef struct _asn1_sequence
+{
+    asn1_buf buf;                   /**< Buffer containing the given ASN.1 item. */
+    struct _asn1_sequence *next;    /**< The next entry in the sequence. */
+}
+asn1_sequence;
+
+/**
+ * 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
+ *
+ * \return      0 if successful, POLARSSL_ERR_ASN1_OUT_OF_DATA on reaching
+ *              end of data, POLARSSL_ERR_ASN1_INVALID_LENGTH if length is
+ *              unparseable.
+ */
+int asn1_get_len( unsigned char **p,
+                  const unsigned char *end,
+                  size_t *len );
+
+/**
+ * Get the tag and length of the tag. 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
+ *
+ * \return      0 if successful, POLARSSL_ERR_ASN1_UNEXPECTED_TAG if tag did
+ *              not match requested tag, or another specific ASN.1 error code.
+ */
+int asn1_get_tag( unsigned char **p,
+                  const unsigned char *end,
+                  size_t *len, int tag );
+
+/**
+ * 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
+ *
+ * \return      0 if successful or a specific ASN.1 error code.
+ */
+int asn1_get_bool( unsigned char **p,
+                   const unsigned char *end,
+                   int *val );
+
+/**
+ * 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
+ *
+ * \return      0 if successful or a specific ASN.1 error code.
+ */
+int asn1_get_int( unsigned char **p,
+                  const unsigned char *end,
+                  int *val );
+
+/**
+ * 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
+ *
+ * \return      0 if successful or a specific ASN.1 error code.
+ */
+int asn1_get_bitstring( unsigned char **p, const unsigned char *end,
+                        asn1_bitstring *bs);
+
+/**
+ * Parses and splits an ASN.1 "SEQUENCE OF <tag>"
+ * Updated 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
+ *
+ * \return      0 if successful or a specific ASN.1 error code.
+ */
+int asn1_get_sequence_of( unsigned char **p,
+                          const unsigned char *end,
+                          asn1_sequence *cur,
+                          int tag);
+
+#if defined(POLARSSL_BIGNUM_C)
+/**
+ * Retrieve a MPI value from an integer ASN.1 tag.
+ * 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
+ *
+ * \return      0 if successful or a specific ASN.1 or MPI error code.
+ */
+int asn1_get_mpi( unsigned char **p,
+                  const unsigned char *end,
+                  mpi *X );
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* asn1.h */