| /** |
| * \file asn1.h |
| * |
| * \brief Generic ASN.1 parsing |
| */ |
| /* |
| * 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_ASN1_H |
| #define MBEDTLS_ASN1_H |
| #include "mbedtls/private_access.h" |
| |
| #include "mbedtls/build_info.h" |
| |
| #include <stddef.h> |
| |
| #if defined(MBEDTLS_BIGNUM_C) |
| #include "mbedtls/bignum.h" |
| #endif |
| |
| /** |
| * \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. |
| * \{ |
| */ |
| /** Out of data when parsing an ASN1 data structure. */ |
| #define MBEDTLS_ERR_ASN1_OUT_OF_DATA -0x0060 |
| /** ASN1 tag was of an unexpected value. */ |
| #define MBEDTLS_ERR_ASN1_UNEXPECTED_TAG -0x0062 |
| /** Error when trying to determine the length or invalid length. */ |
| #define MBEDTLS_ERR_ASN1_INVALID_LENGTH -0x0064 |
| /** Actual length differs from expected length. */ |
| #define MBEDTLS_ERR_ASN1_LENGTH_MISMATCH -0x0066 |
| /** Data is invalid. */ |
| #define MBEDTLS_ERR_ASN1_INVALID_DATA -0x0068 |
| /** Memory allocation failed */ |
| #define MBEDTLS_ERR_ASN1_ALLOC_FAILED -0x006A |
| /** Buffer too small when writing ASN.1 data structure. */ |
| #define MBEDTLS_ERR_ASN1_BUF_TOO_SMALL -0x006C |
| |
| /** \} name ASN1 Error codes */ |
| |
| /** |
| * \name DER constants |
| * These constants comply with the DER encoded ASN.1 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 ::mbedtls_x509_buf. |
| * \{ |
| */ |
| #define MBEDTLS_ASN1_BOOLEAN 0x01 |
| #define MBEDTLS_ASN1_INTEGER 0x02 |
| #define MBEDTLS_ASN1_BIT_STRING 0x03 |
| #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 |
| #define MBEDTLS_ASN1_PRINTABLE_STRING 0x13 |
| #define MBEDTLS_ASN1_T61_STRING 0x14 |
| #define MBEDTLS_ASN1_IA5_STRING 0x16 |
| #define MBEDTLS_ASN1_UTC_TIME 0x17 |
| #define MBEDTLS_ASN1_GENERALIZED_TIME 0x18 |
| #define MBEDTLS_ASN1_UNIVERSAL_STRING 0x1C |
| #define MBEDTLS_ASN1_BMP_STRING 0x1E |
| #define MBEDTLS_ASN1_PRIMITIVE 0x00 |
| #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", |
| * paragraph 8.1.2.2: |
| * |
| * Bit 8 7 6 5 1 |
| * +-------+-----+------------+ |
| * | Class | P/C | Tag number | |
| * +-------+-----+------------+ |
| */ |
| #define MBEDTLS_ASN1_TAG_CLASS_MASK 0xC0 |
| #define MBEDTLS_ASN1_TAG_PC_MASK 0x20 |
| #define MBEDTLS_ASN1_TAG_VALUE_MASK 0x1F |
| |
| /** \} name DER constants */ |
| |
| /** Returns the size of the binary string, without the trailing \\0 */ |
| #define MBEDTLS_OID_SIZE(x) (sizeof(x) - 1) |
| |
| /** |
| * Compares an mbedtls_asn1_buf structure to a reference OID. |
| * |
| * Only works for 'defined' oid_str values (MBEDTLS_OID_HMAC_SHA1), you cannot use a |
| * 'unsigned char *oid' here! |
| */ |
| #define MBEDTLS_OID_CMP(oid_str, oid_buf) \ |
| ( ( 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 |
| |
| /** |
| * \name Functions to parse ASN.1 data structures |
| * \{ |
| */ |
| |
| /** |
| * Type-length-value structure that allows for ASN1 using DER. |
| */ |
| 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. */ |
| } |
| mbedtls_asn1_buf; |
| |
| /** |
| * Container for ASN1 bit strings. |
| */ |
| 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 */ |
| } |
| mbedtls_asn1_bitstring; |
| |
| /** |
| * Container for a sequence of ASN.1 items |
| */ |
| typedef struct mbedtls_asn1_sequence |
| { |
| mbedtls_asn1_buf buf; /**< Buffer containing the given ASN.1 item. */ |
| |
| /** The next entry in the sequence. |
| * |
| * The details of memory management for sequences are not documented and |
| * may change in future versions. Set this field to \p NULL when |
| * initializing a structure, and do not modify it except via Mbed TLS |
| * library functions. |
| */ |
| struct mbedtls_asn1_sequence *next; |
| } |
| mbedtls_asn1_sequence; |
| |
| /** |
| * Container for a sequence or list of 'named' ASN.1 data items |
| */ |
| typedef struct mbedtls_asn1_named_data |
| { |
| mbedtls_asn1_buf oid; /**< The object identifier. */ |
| mbedtls_asn1_buf val; /**< The named value. */ |
| |
| /** The next entry in the sequence. |
| * |
| * The details of memory management for named data sequences are not |
| * documented and may change in future versions. Set this field to \p NULL |
| * when initializing a structure, and do not modify it except via Mbed TLS |
| * library functions. |
| */ |
| struct mbedtls_asn1_named_data *next; |
| |
| /** Merge next item into the current one? |
| * |
| * This field exists for the sake of Mbed TLS's X.509 certificate parsing |
| * code and may change in future versions of the library. |
| */ |
| unsigned char MBEDTLS_PRIVATE(next_merged); |
| } |
| mbedtls_asn1_named_data; |
| |
| /** |
| * \brief Get the length of an ASN.1 element. |
| * Updates the pointer to immediately behind the length. |
| * |
| * \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. |
| * \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 ); |
| |
| /** |
| * \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 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. |
| * \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 ); |
| |
| /** |
| * \brief Retrieve a boolean 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 (\c 0 or \c 1). |
| * |
| * \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 ); |
| |
| /** |
| * \brief Retrieve an integer 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 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 ); |
| |
| /** |
| * \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 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. |
| * \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 ); |
| |
| /** |
| * \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 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. |
| * \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 ); |
| |
| /** |
| * \brief Parses and splits an ASN.1 "SEQUENCE OF <tag>". |
| * Updates the pointer to immediately behind the full sequence tag. |
| * |
| * This function allocates memory for the sequence elements. You can free |
| * the allocated memory with mbedtls_asn1_sequence_free(). |
| * |
| * \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 ); |
| /** |
| * \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 an integer 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 X 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 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 ); |
| #endif /* MBEDTLS_BIGNUM_C */ |
| |
| /** |
| * \brief Retrieve an AlgorithmIdentifier ASN.1 sequence. |
| * Updates the pointer to immediately behind the full |
| * AlgorithmIdentifier. |
| * |
| * \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. |
| */ |
| int mbedtls_asn1_get_alg( unsigned char **p, |
| const unsigned char *end, |
| mbedtls_asn1_buf *alg, mbedtls_asn1_buf *params ); |
| |
| /** |
| * \brief Retrieve an AlgorithmIdentifier ASN.1 sequence with NULL or no |
| * params. |
| * Updates the pointer to immediately behind the full |
| * AlgorithmIdentifier. |
| * |
| * \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. |
| */ |
| int mbedtls_asn1_get_alg_null( unsigned char **p, |
| const unsigned char *end, |
| mbedtls_asn1_buf *alg ); |
| |
| /** |
| * \brief Find a specific named_data entry in a sequence or list based on |
| * the OID. |
| * |
| * \param list The list to seek through |
| * \param oid The OID to look for |
| * \param len Size of the OID |
| * |
| * \return NULL if not found, or a pointer to the existing entry. |
| */ |
| 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. |
| * 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. |
| * |
| * \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 ); |
| |
| /** \} name Functions to parse ASN.1 data structures */ |
| /** \} addtogroup asn1_module */ |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* asn1.h */ |