| /** |
| * \file cipher.h |
| * |
| * \brief Generic cipher wrapper. |
| * |
| * \author Adriaan de Jong <dejong@fox-it.com> |
| * |
| * Copyright (C) 2006-2014, 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_CIPHER_H |
| #define POLARSSL_CIPHER_H |
| |
| #if !defined(POLARSSL_CONFIG_FILE) |
| #include "config.h" |
| #else |
| #include POLARSSL_CONFIG_FILE |
| #endif |
| |
| #if defined(POLARSSL_GCM_C) |
| #define POLARSSL_CIPHER_MODE_AEAD |
| #endif |
| |
| #if defined(POLARSSL_CIPHER_MODE_CBC) |
| #define POLARSSL_CIPHER_MODE_WITH_PADDING |
| #endif |
| |
| #include <string.h> |
| |
| #if defined(_MSC_VER) && !defined(inline) |
| #define inline _inline |
| #else |
| #if defined(__ARMCC_VERSION) && !defined(inline) |
| #define inline __inline |
| #endif /* __ARMCC_VERSION */ |
| #endif /*_MSC_VER */ |
| |
| #define POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE -0x6080 /**< The selected feature is not available. */ |
| #define POLARSSL_ERR_CIPHER_BAD_INPUT_DATA -0x6100 /**< Bad input parameters to function. */ |
| #define POLARSSL_ERR_CIPHER_ALLOC_FAILED -0x6180 /**< Failed to allocate memory. */ |
| #define POLARSSL_ERR_CIPHER_INVALID_PADDING -0x6200 /**< Input data contains invalid padding and is rejected. */ |
| #define POLARSSL_ERR_CIPHER_FULL_BLOCK_EXPECTED -0x6280 /**< Decryption of block requires a full block. */ |
| #define POLARSSL_ERR_CIPHER_AUTH_FAILED -0x6300 /**< Authentication failed (for AEAD modes). */ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| typedef enum { |
| POLARSSL_CIPHER_ID_NONE = 0, |
| POLARSSL_CIPHER_ID_NULL, |
| POLARSSL_CIPHER_ID_AES, |
| POLARSSL_CIPHER_ID_DES, |
| POLARSSL_CIPHER_ID_3DES, |
| POLARSSL_CIPHER_ID_CAMELLIA, |
| POLARSSL_CIPHER_ID_BLOWFISH, |
| POLARSSL_CIPHER_ID_ARC4, |
| } cipher_id_t; |
| |
| typedef enum { |
| POLARSSL_CIPHER_NONE = 0, |
| POLARSSL_CIPHER_NULL, |
| POLARSSL_CIPHER_AES_128_ECB, |
| POLARSSL_CIPHER_AES_192_ECB, |
| POLARSSL_CIPHER_AES_256_ECB, |
| POLARSSL_CIPHER_AES_128_CBC, |
| POLARSSL_CIPHER_AES_192_CBC, |
| POLARSSL_CIPHER_AES_256_CBC, |
| POLARSSL_CIPHER_AES_128_CFB128, |
| POLARSSL_CIPHER_AES_192_CFB128, |
| POLARSSL_CIPHER_AES_256_CFB128, |
| POLARSSL_CIPHER_AES_128_CTR, |
| POLARSSL_CIPHER_AES_192_CTR, |
| POLARSSL_CIPHER_AES_256_CTR, |
| POLARSSL_CIPHER_AES_128_GCM, |
| POLARSSL_CIPHER_AES_192_GCM, |
| POLARSSL_CIPHER_AES_256_GCM, |
| POLARSSL_CIPHER_CAMELLIA_128_ECB, |
| POLARSSL_CIPHER_CAMELLIA_192_ECB, |
| POLARSSL_CIPHER_CAMELLIA_256_ECB, |
| POLARSSL_CIPHER_CAMELLIA_128_CBC, |
| POLARSSL_CIPHER_CAMELLIA_192_CBC, |
| POLARSSL_CIPHER_CAMELLIA_256_CBC, |
| POLARSSL_CIPHER_CAMELLIA_128_CFB128, |
| POLARSSL_CIPHER_CAMELLIA_192_CFB128, |
| POLARSSL_CIPHER_CAMELLIA_256_CFB128, |
| POLARSSL_CIPHER_CAMELLIA_128_CTR, |
| POLARSSL_CIPHER_CAMELLIA_192_CTR, |
| POLARSSL_CIPHER_CAMELLIA_256_CTR, |
| POLARSSL_CIPHER_CAMELLIA_128_GCM, |
| POLARSSL_CIPHER_CAMELLIA_192_GCM, |
| POLARSSL_CIPHER_CAMELLIA_256_GCM, |
| POLARSSL_CIPHER_DES_ECB, |
| POLARSSL_CIPHER_DES_CBC, |
| POLARSSL_CIPHER_DES_EDE_ECB, |
| POLARSSL_CIPHER_DES_EDE_CBC, |
| POLARSSL_CIPHER_DES_EDE3_ECB, |
| POLARSSL_CIPHER_DES_EDE3_CBC, |
| POLARSSL_CIPHER_BLOWFISH_ECB, |
| POLARSSL_CIPHER_BLOWFISH_CBC, |
| POLARSSL_CIPHER_BLOWFISH_CFB64, |
| POLARSSL_CIPHER_BLOWFISH_CTR, |
| POLARSSL_CIPHER_ARC4_128, |
| } cipher_type_t; |
| |
| typedef enum { |
| POLARSSL_MODE_NONE = 0, |
| POLARSSL_MODE_ECB, |
| POLARSSL_MODE_CBC, |
| POLARSSL_MODE_CFB, |
| POLARSSL_MODE_OFB, |
| POLARSSL_MODE_CTR, |
| POLARSSL_MODE_GCM, |
| POLARSSL_MODE_STREAM, |
| } cipher_mode_t; |
| |
| typedef enum { |
| POLARSSL_PADDING_PKCS7 = 0, /**< PKCS7 padding (default) */ |
| POLARSSL_PADDING_ONE_AND_ZEROS, /**< ISO/IEC 7816-4 padding */ |
| POLARSSL_PADDING_ZEROS_AND_LEN, /**< ANSI X.923 padding */ |
| POLARSSL_PADDING_ZEROS, /**< zero padding (not reversible!) */ |
| POLARSSL_PADDING_NONE, /**< never pad (full blocks only) */ |
| } cipher_padding_t; |
| |
| typedef enum { |
| POLARSSL_OPERATION_NONE = -1, |
| POLARSSL_DECRYPT = 0, |
| POLARSSL_ENCRYPT, |
| } operation_t; |
| |
| enum { |
| /** Undefined key length */ |
| POLARSSL_KEY_LENGTH_NONE = 0, |
| /** Key length, in bits (including parity), for DES keys */ |
| POLARSSL_KEY_LENGTH_DES = 64, |
| /** Key length, in bits (including parity), for DES in two key EDE */ |
| POLARSSL_KEY_LENGTH_DES_EDE = 128, |
| /** Key length, in bits (including parity), for DES in three-key EDE */ |
| POLARSSL_KEY_LENGTH_DES_EDE3 = 192, |
| }; |
| |
| /** Maximum length of any IV, in bytes */ |
| #define POLARSSL_MAX_IV_LENGTH 16 |
| /** Maximum block size of any cipher, in bytes */ |
| #define POLARSSL_MAX_BLOCK_LENGTH 16 |
| |
| /** |
| * Base cipher information. The non-mode specific functions and values. |
| */ |
| typedef struct { |
| |
| /** Base Cipher type (e.g. POLARSSL_CIPHER_ID_AES) */ |
| cipher_id_t cipher; |
| |
| /** Encrypt using ECB */ |
| int (*ecb_func)( void *ctx, operation_t mode, |
| const unsigned char *input, unsigned char *output ); |
| |
| /** Encrypt using CBC */ |
| int (*cbc_func)( void *ctx, operation_t mode, size_t length, |
| unsigned char *iv, const unsigned char *input, |
| unsigned char *output ); |
| |
| /** Encrypt using CFB (Full length) */ |
| int (*cfb_func)( void *ctx, operation_t mode, size_t length, size_t *iv_off, |
| unsigned char *iv, const unsigned char *input, |
| unsigned char *output ); |
| |
| /** Encrypt using CTR */ |
| int (*ctr_func)( void *ctx, size_t length, size_t *nc_off, |
| unsigned char *nonce_counter, unsigned char *stream_block, |
| const unsigned char *input, unsigned char *output ); |
| |
| /** Encrypt using STREAM */ |
| int (*stream_func)( void *ctx, size_t length, |
| const unsigned char *input, unsigned char *output ); |
| |
| /** Set key for encryption purposes */ |
| int (*setkey_enc_func)( void *ctx, const unsigned char *key, |
| unsigned int key_length ); |
| |
| /** Set key for decryption purposes */ |
| int (*setkey_dec_func)( void *ctx, const unsigned char *key, |
| unsigned int key_length); |
| |
| /** Allocate a new context */ |
| void * (*ctx_alloc_func)( void ); |
| |
| /** Free the given context */ |
| void (*ctx_free_func)( void *ctx ); |
| |
| } cipher_base_t; |
| |
| /** |
| * Cipher information. Allows cipher functions to be called in a generic way. |
| */ |
| typedef struct { |
| /** Full cipher identifier (e.g. POLARSSL_CIPHER_AES_256_CBC) */ |
| cipher_type_t type; |
| |
| /** Cipher mode (e.g. POLARSSL_MODE_CBC) */ |
| cipher_mode_t mode; |
| |
| /** Cipher key length, in bits (default length for variable sized ciphers) |
| * (Includes parity bits for ciphers like DES) */ |
| unsigned int key_length; |
| |
| /** Name of the cipher */ |
| const char * name; |
| |
| /** IV/NONCE size, in bytes. |
| * For cipher that accept many sizes: recommended size */ |
| unsigned int iv_size; |
| |
| /** Flag for ciphers that accept many sizes of IV/NONCE */ |
| int accepts_variable_iv_size; |
| |
| /** block size, in bytes */ |
| unsigned int block_size; |
| |
| /** Base cipher information and functions */ |
| const cipher_base_t *base; |
| |
| } cipher_info_t; |
| |
| /** |
| * Generic cipher context. |
| */ |
| typedef struct { |
| /** Information about the associated cipher */ |
| const cipher_info_t *cipher_info; |
| |
| /** Key length to use */ |
| int key_length; |
| |
| /** Operation that the context's key has been initialised for */ |
| operation_t operation; |
| |
| /** Padding functions to use, if relevant for cipher mode */ |
| void (*add_padding)( unsigned char *output, size_t olen, size_t data_len ); |
| int (*get_padding)( unsigned char *input, size_t ilen, size_t *data_len ); |
| |
| /** Buffer for data that hasn't been encrypted yet */ |
| unsigned char unprocessed_data[POLARSSL_MAX_BLOCK_LENGTH]; |
| |
| /** Number of bytes that still need processing */ |
| size_t unprocessed_len; |
| |
| /** Current IV or NONCE_COUNTER for CTR-mode */ |
| unsigned char iv[POLARSSL_MAX_IV_LENGTH]; |
| |
| /** IV size in bytes (for ciphers with variable-length IVs) */ |
| size_t iv_size; |
| |
| /** Cipher-specific context */ |
| void *cipher_ctx; |
| } cipher_context_t; |
| |
| /** |
| * \brief Returns the list of ciphers supported by the generic cipher module. |
| * |
| * \return a statically allocated array of ciphers, the last entry |
| * is 0. |
| */ |
| const int *cipher_list( void ); |
| |
| /** |
| * \brief Returns the cipher information structure associated |
| * with the given cipher name. |
| * |
| * \param cipher_name Name of the cipher to search for. |
| * |
| * \return the cipher information structure associated with the |
| * given cipher_name, or NULL if not found. |
| */ |
| const cipher_info_t *cipher_info_from_string( const char *cipher_name ); |
| |
| /** |
| * \brief Returns the cipher information structure associated |
| * with the given cipher type. |
| * |
| * \param cipher_type Type of the cipher to search for. |
| * |
| * \return the cipher information structure associated with the |
| * given cipher_type, or NULL if not found. |
| */ |
| const cipher_info_t *cipher_info_from_type( const cipher_type_t cipher_type ); |
| |
| /** |
| * \brief Returns the cipher information structure associated |
| * with the given cipher id, key size and mode. |
| * |
| * \param cipher_id Id of the cipher to search for |
| * (e.g. POLARSSL_CIPHER_ID_AES) |
| * \param key_length Length of the key in bits |
| * \param mode Cipher mode (e.g. POLARSSL_MODE_CBC) |
| * |
| * \return the cipher information structure associated with the |
| * given cipher_type, or NULL if not found. |
| */ |
| const cipher_info_t *cipher_info_from_values( const cipher_id_t cipher_id, |
| int key_length, |
| const cipher_mode_t mode ); |
| |
| /** |
| * \brief Initialises and fills the cipher context structure with |
| * the appropriate values. |
| * |
| * \param ctx context to initialise. May not be NULL. |
| * \param cipher_info cipher to use. |
| * |
| * \return 0 on success, |
| * POLARSSL_ERR_CIPHER_BAD_INPUT_DATA on parameter failure, |
| * POLARSSL_ERR_CIPHER_ALLOC_FAILED if allocation of the |
| * cipher-specific context failed. |
| */ |
| int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info ); |
| |
| /** |
| * \brief Free the cipher-specific context of ctx. Freeing ctx |
| * itself remains the responsibility of the caller. |
| * |
| * \param ctx Free the cipher-specific context |
| * |
| * \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if |
| * parameter verification fails. |
| */ |
| int cipher_free_ctx( cipher_context_t *ctx ); |
| |
| /** |
| * \brief Returns the block size of the given cipher. |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return size of the cipher's blocks, or 0 if ctx has not been |
| * initialised. |
| */ |
| static inline unsigned int cipher_get_block_size( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return 0; |
| |
| return ctx->cipher_info->block_size; |
| } |
| |
| /** |
| * \brief Returns the mode of operation for the cipher. |
| * (e.g. POLARSSL_MODE_CBC) |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return mode of operation, or POLARSSL_MODE_NONE if ctx |
| * has not been initialised. |
| */ |
| static inline cipher_mode_t cipher_get_cipher_mode( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return POLARSSL_MODE_NONE; |
| |
| return ctx->cipher_info->mode; |
| } |
| |
| /** |
| * \brief Returns the size of the cipher's IV/NONCE in bytes. |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return If IV has not been set yet: (recommended) IV size |
| * (0 for ciphers not using IV/NONCE). |
| * If IV has already been set: actual size. |
| */ |
| static inline int cipher_get_iv_size( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return 0; |
| |
| if( ctx->iv_size != 0 ) |
| return (int) ctx->iv_size; |
| |
| return ctx->cipher_info->iv_size; |
| } |
| |
| /** |
| * \brief Returns the type of the given cipher. |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return type of the cipher, or POLARSSL_CIPHER_NONE if ctx has |
| * not been initialised. |
| */ |
| static inline cipher_type_t cipher_get_type( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return POLARSSL_CIPHER_NONE; |
| |
| return ctx->cipher_info->type; |
| } |
| |
| /** |
| * \brief Returns the name of the given cipher, as a string. |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return name of the cipher, or NULL if ctx was not initialised. |
| */ |
| static inline const char *cipher_get_name( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return 0; |
| |
| return ctx->cipher_info->name; |
| } |
| |
| /** |
| * \brief Returns the key length of the cipher. |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return cipher's key length, in bits, or |
| * POLARSSL_KEY_LENGTH_NONE if ctx has not been |
| * initialised. |
| */ |
| static inline int cipher_get_key_size ( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return POLARSSL_KEY_LENGTH_NONE; |
| |
| return ctx->cipher_info->key_length; |
| } |
| |
| /** |
| * \brief Returns the operation of the given cipher. |
| * |
| * \param ctx cipher's context. Must have been initialised. |
| * |
| * \return operation (POLARSSL_ENCRYPT or POLARSSL_DECRYPT), |
| * or POLARSSL_OPERATION_NONE if ctx has not been |
| * initialised. |
| */ |
| static inline operation_t cipher_get_operation( const cipher_context_t *ctx ) |
| { |
| if( NULL == ctx || NULL == ctx->cipher_info ) |
| return POLARSSL_OPERATION_NONE; |
| |
| return ctx->operation; |
| } |
| |
| /** |
| * \brief Set the key to use with the given context. |
| * |
| * \param ctx generic cipher context. May not be NULL. Must have been |
| * initialised using cipher_context_from_type or |
| * cipher_context_from_string. |
| * \param key The key to use. |
| * \param key_length key length to use, in bits. |
| * \param operation Operation that the key will be used for, either |
| * POLARSSL_ENCRYPT or POLARSSL_DECRYPT. |
| * |
| * \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if |
| * parameter verification fails or a cipher specific |
| * error code. |
| */ |
| int cipher_setkey( cipher_context_t *ctx, const unsigned char *key, |
| int key_length, const operation_t operation ); |
| |
| #if defined(POLARSSL_CIPHER_MODE_WITH_PADDING) |
| /** |
| * \brief Set padding mode, for cipher modes that use padding. |
| * (Default: PKCS7 padding.) |
| * |
| * \param ctx generic cipher context |
| * \param mode padding mode |
| * |
| * \returns 0 on success, POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE |
| * if selected padding mode is not supported, or |
| * POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if the cipher mode |
| * does not support padding. |
| */ |
| int cipher_set_padding_mode( cipher_context_t *ctx, cipher_padding_t mode ); |
| #endif /* POLARSSL_CIPHER_MODE_WITH_PADDING */ |
| |
| /** |
| * \brief Set the initialization vector (IV) or nonce |
| * |
| * \param ctx generic cipher context |
| * \param iv IV to use (or NONCE_COUNTER for CTR-mode ciphers) |
| * \param iv_len IV length for ciphers with variable-size IV; |
| * discarded by ciphers with fixed-size IV. |
| * |
| * \returns O on success, or POLARSSL_ERR_CIPHER_BAD_INPUT_DATA |
| * |
| * \note Some ciphers don't use IVs nor NONCE. For these |
| * ciphers, this function has no effect. |
| */ |
| int cipher_set_iv( cipher_context_t *ctx, |
| const unsigned char *iv, size_t iv_len ); |
| |
| /** |
| * \brief Finish preparation of the given context |
| * |
| * \param ctx generic cipher context |
| * |
| * \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA |
| * if parameter verification fails. |
| */ |
| int cipher_reset( cipher_context_t *ctx ); |
| |
| #if defined(POLARSSL_CIPHER_MODE_AEAD) |
| /** |
| * \brief Add additional data (for AEAD ciphers). |
| * This function has no effect for non-AEAD ciphers. |
| * For AEAD ciphers, it may or may not be called |
| * repeatedly, and/or interleaved with calls to |
| * cipher_udpate(), depending on the cipher. |
| * E.g. for GCM is must be called exactly once, right |
| * after cipher_reset(). |
| * |
| * \param ctx generic cipher context |
| * \param ad Additional data to use. |
| * \param ad_len Length of ad. |
| * |
| * \returns 0 on success, or a specific error code. |
| */ |
| int cipher_update_ad( cipher_context_t *ctx, |
| const unsigned char *ad, size_t ad_len ); |
| #endif /* POLARSSL_CIPHER_MODE_AEAD */ |
| |
| /** |
| * \brief Generic cipher update function. Encrypts/decrypts |
| * using the given cipher context. Writes as many block |
| * size'd blocks of data as possible to output. Any data |
| * that cannot be written immediately will either be added |
| * to the next block, or flushed when cipher_final is |
| * called. |
| * Exception: for POLARSSL_MODE_ECB, expects single block |
| * in size (e.g. 16 bytes for AES) |
| * |
| * \param ctx generic cipher context |
| * \param input buffer holding the input data |
| * \param ilen length of the input data |
| * \param output buffer for the output data. Should be able to hold at |
| * least ilen + block_size. Cannot be the same buffer as |
| * input! |
| * \param olen length of the output data, will be filled with the |
| * actual number of bytes written. |
| * |
| * \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if |
| * parameter verification fails, |
| * POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE on an |
| * unsupported mode for a cipher or a cipher specific |
| * error code. |
| * |
| * \note If the underlying cipher is GCM, all calls to this |
| * function, except the last one before cipher_finish(), |
| * must have ilen a multiple of the block size. |
| */ |
| int cipher_update( cipher_context_t *ctx, const unsigned char *input, |
| size_t ilen, unsigned char *output, size_t *olen ); |
| |
| /** |
| * \brief Generic cipher finalisation function. If data still |
| * needs to be flushed from an incomplete block, data |
| * contained within it will be padded with the size of |
| * the last block, and written to the output buffer. |
| * |
| * \param ctx Generic cipher context |
| * \param output buffer to write data to. Needs block_size available. |
| * \param olen length of the data written to the output buffer. |
| * |
| * \returns 0 on success, POLARSSL_ERR_CIPHER_BAD_INPUT_DATA if |
| * parameter verification fails, |
| * POLARSSL_ERR_CIPHER_FULL_BLOCK_EXPECTED if decryption |
| * expected a full block but was not provided one, |
| * POLARSSL_ERR_CIPHER_INVALID_PADDING on invalid padding |
| * while decrypting or a cipher specific error code. |
| */ |
| int cipher_finish( cipher_context_t *ctx, |
| unsigned char *output, size_t *olen ); |
| |
| #if defined(POLARSSL_CIPHER_MODE_AEAD) |
| /** |
| * \brief Write tag for AEAD ciphers. |
| * No effect for other ciphers. |
| * Must be called after cipher_finish(). |
| * |
| * \param ctx Generic cipher context |
| * \param tag buffer to write the tag |
| * \param tag_len Length of the tag to write |
| * |
| * \return 0 on success, or a specific error code. |
| */ |
| int cipher_write_tag( cipher_context_t *ctx, |
| unsigned char *tag, size_t tag_len ); |
| |
| /** |
| * \brief Check tag for AEAD ciphers. |
| * No effect for other ciphers. |
| * Calling time depends on the cipher: |
| * for GCM, must be called after cipher_finish(). |
| * |
| * \param ctx Generic cipher context |
| * \param tag Buffer holding the tag |
| * \param tag_len Length of the tag to check |
| * |
| * \return 0 on success, or a specific error code. |
| */ |
| int cipher_check_tag( cipher_context_t *ctx, |
| const unsigned char *tag, size_t tag_len ); |
| #endif /* POLARSSL_CIPHER_MODE_AEAD */ |
| |
| /** |
| * \brief Checkup routine |
| * |
| * \return 0 if successful, or 1 if the test failed |
| */ |
| int cipher_self_test( int verbose ); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* POLARSSL_CIPHER_H */ |
