Improve wording and formatting of ASN.1 write module documentation
diff --git a/include/mbedtls/asn1write.h b/include/mbedtls/asn1write.h
index 59e5d52..76c1780 100644
--- a/include/mbedtls/asn1write.h
+++ b/include/mbedtls/asn1write.h
@@ -26,139 +26,171 @@
#include "asn1.h"
-#define MBEDTLS_ASN1_CHK_ADD(g, f) do { if( ( ret = f ) < 0 ) return( ret ); else \
- g += ret; } while( 0 )
+#define MBEDTLS_ASN1_CHK_ADD(g, f) \
+ do { \
+ if( ( ret = f ) < 0 ) \
+ return( ret ); \
+ else \
+ g += ret; \
+ } while( 0 )
#ifdef __cplusplus
extern "C" {
#endif
/**
- * \brief Write a length field in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write a length field in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param len the length to write
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param len The length value to write.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
-int mbedtls_asn1_write_len( unsigned char **p, unsigned char *start, size_t len );
-
+int mbedtls_asn1_write_len( unsigned char **p, unsigned char *start,
+ size_t len );
/**
- * \brief Write a ASN.1 tag in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write an ASN.1 tag in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param tag the tag to write
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param tag The tag to write.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
int mbedtls_asn1_write_tag( unsigned char **p, unsigned char *start,
- unsigned char tag );
+ unsigned char tag );
/**
- * \brief Write raw buffer data
- * Note: function works backwards in data buffer
+ * \brief Write raw buffer data.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param buf data buffer to write
- * \param size length of the data buffer
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param buf The data buffer to write.
+ * \param size The length of the data buffer.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
int mbedtls_asn1_write_raw_buffer( unsigned char **p, unsigned char *start,
- const unsigned char *buf, size_t size );
+ const unsigned char *buf, size_t size );
#if defined(MBEDTLS_BIGNUM_C)
/**
- * \brief Write a big number (MBEDTLS_ASN1_INTEGER) in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write a arbitrary-precision number (#MBEDTLS_ASN1_INTEGER)
+ * in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param X the MPI to write
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param X The MPI to write.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
-int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start, const mbedtls_mpi *X );
+int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start,
+ const mbedtls_mpi *X );
#endif /* MBEDTLS_BIGNUM_C */
/**
- * \brief Write a NULL tag (MBEDTLS_ASN1_NULL) with zero data in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write a NULL tag (#MBEDTLS_ASN1_NULL) with zero data
+ * in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
int mbedtls_asn1_write_null( unsigned char **p, unsigned char *start );
/**
- * \brief Write an OID tag (MBEDTLS_ASN1_OID) and data in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write an OID tag (#MBEDTLS_ASN1_OID) and data
+ * in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param oid the OID to write
- * \param oid_len length of the OID
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param oid The OID to write.
+ * \param oid_len The length of the OID.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
int mbedtls_asn1_write_oid( unsigned char **p, unsigned char *start,
- const char *oid, size_t oid_len );
+ const char *oid, size_t oid_len );
/**
- * \brief Write an AlgorithmIdentifier sequence in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write an AlgorithmIdentifier sequence in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param oid the OID of the algorithm
- * \param oid_len length of the OID
- * \param par_len length of parameters, which must be already written.
+ * \note This function works backwards in data buffer.
+ *
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param oid The OID of the algorithm to write.
+ * \param oid_len The length of the algorithm's OID.
+ * \param par_len The length of the parameters, which must be already written.
* If 0, NULL parameters are added
*
- * \return the length written or a negative error code
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
-int mbedtls_asn1_write_algorithm_identifier( unsigned char **p, unsigned char *start,
- const char *oid, size_t oid_len,
- size_t par_len );
+int mbedtls_asn1_write_algorithm_identifier( unsigned char **p,
+ unsigned char *start,
+ const char *oid, size_t oid_len,
+ size_t par_len );
/**
- * \brief Write a boolean tag (MBEDTLS_ASN1_BOOLEAN) and value in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write a boolean tag (#MBEDTLS_ASN1_BOOLEAN) and value
+ * in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param boolean 0 or 1
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param boolean The boolean value to write, either \c 0 or \c 1.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
-int mbedtls_asn1_write_bool( unsigned char **p, unsigned char *start, int boolean );
+int mbedtls_asn1_write_bool( unsigned char **p, unsigned char *start,
+ int boolean );
/**
- * \brief Write an int tag (MBEDTLS_ASN1_INTEGER) and value in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write an int tag (#MBEDTLS_ASN1_INTEGER) and value
+ * in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param val the integer value
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param val The integer value to write.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative \c MBEDTLS_ERR_ASN1_XXX error code on failure.
*/
int mbedtls_asn1_write_int( unsigned char **p, unsigned char *start, int val );
/**
* \brief Write a string in ASN.1 format using a specific
* string encoding tag.
- * Note: function works backwards in data buffer
+
+ * \note This function works backwards in data buffer.
*
* \param p The reference to the current position pointer.
- * \param start The start of the buffer (for bounds-checking).
+ * \param start The start of the buffer, for bounds-checking.
* \param tag The string encoding tag to write, e.g.
* #MBEDTLS_ASN1_UTF8_STRING.
* \param text The string to write.
@@ -169,15 +201,17 @@
* \return A negative error code on failure.
*/
int mbedtls_asn1_write_tagged_string( unsigned char **p, unsigned char *start,
- int tag, const char *text, size_t text_len );
+ int tag, const char *text,
+ size_t text_len );
/**
* \brief Write a string in ASN.1 format using the PrintableString
* string encoding tag (#MBEDTLS_ASN1_PRINTABLE_STRING).
- * Note: The function works backwards in data buffer.
+ *
+ * \note This function works backwards in data buffer.
*
* \param p The reference to the current position pointer.
- * \param start The start of the buffer (for bounds-checking).
+ * \param start The start of the buffer, for bounds-checking.
* \param text The string to write.
* \param text_len The length of \p text in bytes (which might
* be strictly larger than the number of characters).
@@ -192,10 +226,11 @@
/**
* \brief Write a UTF8 string in ASN.1 format using the UTF8String
* string encoding tag (#MBEDTLS_ASN1_PRINTABLE_STRING).
- * Note: The function works backwards in data buffer.
+ *
+ * \note This function works backwards in data buffer.
*
* \param p The reference to the current position pointer.
- * \param start The start of the buffer (for bounds-checking).
+ * \param start The start of the buffer, for bounds-checking.
* \param text The string to write.
* \param text_len The length of \p text in bytes (which might
* be strictly larger than the number of characters).
@@ -207,12 +242,13 @@
const char *text, size_t text_len );
/**
- * \brief Write a string in ASN.1 format using the IA5tring
+ * \brief Write a string in ASN.1 format using the IA5String
* string encoding tag (#MBEDTLS_ASN1_IA5_STRING).
- * Note: The function works backwards in data buffer.
+ *
+ * \note This function works backwards in data buffer.
*
* \param p The reference to the current position pointer.
- * \param start The start of the buffer (for bounds-checking).
+ * \param start The start of the buffer, for bounds-checking.
* \param text The string to write.
* \param text_len The length of \p text in bytes (which might
* be strictly larger than the number of characters).
@@ -224,34 +260,38 @@
const char *text, size_t text_len );
/**
- * \brief Write a bitstring tag (MBEDTLS_ASN1_BIT_STRING) and
- * value in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write a bitstring tag (#MBEDTLS_ASN1_BIT_STRING) and
+ * value in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param buf the bitstring
- * \param bits the total number of bits in the bitstring
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param buf The bitstring to write.
+ * \param bits The total number of bits in the bitstring.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative error code on failure.
*/
int mbedtls_asn1_write_bitstring( unsigned char **p, unsigned char *start,
- const unsigned char *buf, size_t bits );
+ const unsigned char *buf, size_t bits );
/**
- * \brief Write an octet string tag (MBEDTLS_ASN1_OCTET_STRING) and
- * value in ASN.1 format
- * Note: function works backwards in data buffer
+ * \brief Write an octet string tag (#MBEDTLS_ASN1_OCTET_STRING)
+ * and value in ASN.1 format.
*
- * \param p reference to current position pointer
- * \param start start of the buffer (for bounds-checking)
- * \param buf data buffer to write
- * \param size length of the data buffer
+ * \note This function works backwards in data buffer.
*
- * \return the length written or a negative error code
+ * \param p The reference to the current position pointer.
+ * \param start The start of the buffer, for bounds-checking.
+ * \param buf The buffer holding the data to write.
+ * \param size The length of the data buffer \p buf.
+ *
+ * \return The number of bytes written to \p p on success.
+ * \return A negative error code on failure.
*/
int mbedtls_asn1_write_octet_string( unsigned char **p, unsigned char *start,
- const unsigned char *buf, size_t size );
+ const unsigned char *buf, size_t size );
/**
* \brief Create or find a specific named_data entry for writing in a
@@ -259,15 +299,16 @@
* a new entry is added to the head of the list.
* Warning: Destructive behaviour for the val data!
*
- * \param list Pointer to the location of the head of the list to seek
- * through (will be updated in case of a new entry)
- * \param oid The OID to look for
- * \param oid_len Size of the OID
- * \param val Data to store (can be NULL if you want to fill it by hand)
- * \param val_len Minimum length of the data buffer needed
+ * \param list The pointer to the location of the head of the list to seek
+ * through (will be updated in case of a new entry).
+ * \param oid The OID to look for.
+ * \param oid_len The size of the OID.
+ * \param val The data to store (can be \c NULL if you want to fill
+ * it by hand).
+ * \param val_len The minimum length of the data buffer needed.
*
- * \return NULL if if there was a memory allocation error, or a pointer
- * to the new / existing entry.
+ * \return A pointer to the new / existing entry on success.
+ * \return \c NULL if if there was a memory allocation error.
*/
mbedtls_asn1_named_data *mbedtls_asn1_store_named_data( mbedtls_asn1_named_data **list,
const char *oid, size_t oid_len,