| /** |
| * \file asn1.h |
| * |
| * \brief Generic ASN.1 parsing |
| * |
| * Copyright (C) 2006-2013, ARM Limited, All Rights Reserved |
| * |
| * This file is part of mbed TLS (https://polarssl.org) |
| * |
| * 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 |
| |
| #if !defined(POLARSSL_CONFIG_FILE) |
| #include "config.h" |
| #else |
| #include POLARSSL_CONFIG_FILE |
| #endif |
| |
| #include <stddef.h> |
| |
| #if defined(POLARSSL_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 POLARSSL_ERR_ASN1_OUT_OF_DATA -0x0060 /**< Out of data when parsing an ASN1 data structure. */ |
| #define POLARSSL_ERR_ASN1_UNEXPECTED_TAG -0x0062 /**< ASN1 tag was of an unexpected value. */ |
| #define POLARSSL_ERR_ASN1_INVALID_LENGTH -0x0064 /**< Error when trying to determine the length or invalid length. */ |
| #define POLARSSL_ERR_ASN1_LENGTH_MISMATCH -0x0066 /**< Actual length differs from expected length. */ |
| #define POLARSSL_ERR_ASN1_INVALID_DATA -0x0068 /**< Data is invalid. (not used) */ |
| #define POLARSSL_ERR_ASN1_MALLOC_FAILED -0x006A /**< Memory allocation failed */ |
| #define POLARSSL_ERR_ASN1_BUF_TOO_SMALL -0x006C /**< Buffer too small when writing ASN.1 data structure. */ |
| |
| /* \} 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) |
| |
| /** |
| * Compares an asn1_buf structure to a reference OID. |
| * |
| * Only works for 'defined' oid_str values (OID_HMAC_SHA1), you cannot use a |
| * 'unsigned char *oid' here! |
| * |
| * Warning: returns true when the OIDs are equal (unlike memcmp)! |
| */ |
| #define OID_CMP(oid_str, oid_buf) \ |
| ( ( OID_SIZE(oid_str) == (oid_buf)->len ) && \ |
| memcmp( (oid_str), (oid_buf)->p, (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 _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; |
| |
| /** |
| * Container for a sequence or list of 'named' ASN.1 data items |
| */ |
| typedef struct _asn1_named_data |
| { |
| asn1_buf oid; /**< The object identifier. */ |
| asn1_buf val; /**< The named value. */ |
| struct _asn1_named_data *next; /**< The next entry in the sequence. */ |
| unsigned char next_merged; /**< Merge next item into the current one? */ |
| } |
| 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, 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 ); |
| |
| /** |
| * \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, 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 ); |
| |
| /** |
| * \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 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 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 asn1_get_bitstring( unsigned char **p, const unsigned char *end, |
| 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 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. |
| * |
| * \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 |
| * |
| * \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) |
| /** |
| * \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 asn1_get_mpi( unsigned char **p, |
| const unsigned char *end, |
| mpi *X ); |
| #endif /* POLARSSL_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 asn1_get_alg( unsigned char **p, |
| const unsigned char *end, |
| asn1_buf *alg, 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 asn1_get_alg_null( unsigned char **p, |
| const unsigned char *end, |
| 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. |
| */ |
| asn1_named_data *asn1_find_named_data( asn1_named_data *list, |
| const char *oid, size_t len ); |
| |
| /** |
| * \brief Free a asn1_named_data entry |
| * |
| * \param entry The named data entry to free |
| */ |
| void asn1_free_named_data( asn1_named_data *entry ); |
| |
| /** |
| * \brief Free all entries in a 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 asn1_free_named_data_list( asn1_named_data **head ); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* asn1.h */ |