| /** |
| * \file asn1.h |
| * |
| * \brief Generic ASN.1 parsing |
| */ |
| /* |
| * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved |
| * 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. |
| * |
| * This file is part of mbed TLS (https://tls.mbed.org) |
| */ |
| #ifndef MBEDTLS_ASN1_H |
| #define MBEDTLS_ASN1_H |
| |
| #if !defined(MBEDTLS_CONFIG_FILE) |
| #include "config.h" |
| #else |
| #include MBEDTLS_CONFIG_FILE |
| #endif |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #if defined(MBEDTLS_BIGNUM_C) |
| #include "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. |
| * \{ |
| */ |
| #define MBEDTLS_ERR_ASN1_OUT_OF_DATA -0x0060 /**< Out of data when parsing an ASN1 data structure. */ |
| #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_ALLOC_FAILED -0x006A /**< Memory allocation failed */ |
| #define MBEDTLS_ERR_ASN1_BUF_TOO_SMALL -0x006C /**< Buffer too small when writing ASN.1 data structure. */ |
| |
| /* \} name */ |
| |
| /** |
| * \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_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 */ |
| /* \} addtogroup asn1_module */ |
| |
| /** 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 ) || \ |
| mbedtls_platform_memequal( (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) ) || \ |
| mbedtls_platform_memequal( (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. */ |
| struct mbedtls_asn1_sequence *next; /**< The next entry in the sequence. */ |
| } |
| 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. */ |
| 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_named_data; |
| |
| /** |
| * \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 |
| * |
| * \return 0 if successful, MBEDTLS_ERR_ASN1_OUT_OF_DATA on reaching |
| * end of data, MBEDTLS_ERR_ASN1_INVALID_LENGTH if 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 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, MBEDTLS_ERR_ASN1_UNEXPECTED_TAG if tag did |
| * not match requested tag, or another specific ASN.1 error code. |
| */ |
| 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 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 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 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 mbedtls_asn1_get_int( 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 |
| * |
| * \return 0 if successful or a specific ASN.1 error code. |
| */ |
| 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 The position in the ASN.1 data |
| * \param end End of data |
| * \param len Length of the actual bit/octect string in bytes |
| * |
| * \return 0 if successful or a specific ASN.1 error code. |
| */ |
| int mbedtls_asn1_get_bitstring_null( unsigned char **p, const unsigned char *end, |
| size_t *len ); |
| |
| /** |
| * \brief Free a heap-allocated linked list presentation of |
| * an ASN.1 sequence, including the first element. |
| * |
| * \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 This function parses and splits an ASN.1 "SEQUENCE OF <tag>" |
| * and updates the source buffer pointer to immediately behind |
| * the full sequence. |
| * |
| * \param p The address of the pointer to the beginning of the |
| * ASN.1 SEQUENCE OF structure, including ASN.1 tag+length header. |
| * On success, `*p` is advanced to point to the first byte |
| * following the parsed ASN.1 sequence. |
| * \param end The end of the ASN.1 input buffer starting at \p p. This is |
| * used for bounds checking. |
| * \param cur The address at which to store the first entry in the parsed |
| * sequence. Further entries are heap-allocated and referenced |
| * from \p cur. |
| * \param tag The common tag of the entries in the ASN.1 sequence. |
| * |
| * \note Ownership for the heap-allocated elements \c cur->next, |
| * \c cur->next->next, ..., is passed to the caller. It |
| * is hence the caller's responsibility to free them when |
| * no longer needed, and mbedtls_asn1_sequence_free() can |
| * be used for that, passing \c cur->next as the \c seq |
| * argument (or \p cur if \p cur itself was heap-allocated |
| * by the caller). |
| * |
| * \return 0 if successful or a specific ASN.1 error code. |
| */ |
| int mbedtls_asn1_get_sequence_of( unsigned char **p, |
| const unsigned char *end, |
| mbedtls_asn1_sequence *cur, |
| int tag ); |
| |
| /** |
| * \brief Traverse an ASN.1 SEQUENCE container and |
| * call a callback for each entry. |
| * |
| * \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. 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 A negative ASN.1 error code on a parsing failure. |
| * \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, |
| uint8_t tag_must_mask, uint8_t tag_must_val, |
| uint8_t tag_may_mask, uint8_t 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. |
| * 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 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 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) |
| * |
| * \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 The position in the ASN.1 data |
| * \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. |
| */ |
| mbedtls_asn1_named_data *mbedtls_asn1_find_named_data( 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 |
| */ |
| 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 |
| * |
| * \param head Pointer to the head of the list of named data entries to free |
| */ |
| void mbedtls_asn1_free_named_data_list( mbedtls_asn1_named_data **head ); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* asn1.h */ |