1/* Copyright (c) 2015, Google Inc. 2 * 3 * Permission to use, copy, modify, and/or distribute this software for any 4 * purpose with or without fee is hereby granted, provided that the above 5 * copyright notice and this permission notice appear in all copies. 6 * 7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ 14 15#ifndef OPENSSL_HEADER_CMAC_H 16#define OPENSSL_HEADER_CMAC_H 17 18#include <openssl/base.h> 19 20#if defined(__cplusplus) 21extern "C" { 22#endif 23 24 25// CMAC. 26// 27// CMAC is a MAC based on AES-CBC and defined in 28// https://tools.ietf.org/html/rfc4493#section-2.3. 29 30 31// One-shot functions. 32 33// AES_CMAC calculates the 16-byte, CMAC authenticator of |in_len| bytes of 34// |in| and writes it to |out|. The |key_len| may be 16 or 32 bytes to select 35// between AES-128 and AES-256. It returns one on success or zero on error. 36OPENSSL_EXPORT int AES_CMAC(uint8_t out[16], const uint8_t *key, size_t key_len, 37 const uint8_t *in, size_t in_len); 38 39 40// Incremental interface. 41 42// CMAC_CTX_new allocates a fresh |CMAC_CTX| and returns it, or NULL on 43// error. 44OPENSSL_EXPORT CMAC_CTX *CMAC_CTX_new(void); 45 46// CMAC_CTX_free frees a |CMAC_CTX|. 47OPENSSL_EXPORT void CMAC_CTX_free(CMAC_CTX *ctx); 48 49// CMAC_Init configures |ctx| to use the given |key| and |cipher|. The CMAC RFC 50// only specifies the use of AES-128 thus |key_len| should be 16 and |cipher| 51// should be |EVP_aes_128_cbc()|. However, this implementation also supports 52// AES-256 by setting |key_len| to 32 and |cipher| to |EVP_aes_256_cbc()|. The 53// |engine| argument is ignored. 54// 55// It returns one on success or zero on error. 56OPENSSL_EXPORT int CMAC_Init(CMAC_CTX *ctx, const void *key, size_t key_len, 57 const EVP_CIPHER *cipher, ENGINE *engine); 58 59 60// CMAC_Reset resets |ctx| so that a fresh message can be authenticated. 61OPENSSL_EXPORT int CMAC_Reset(CMAC_CTX *ctx); 62 63// CMAC_Update processes |in_len| bytes of message from |in|. It returns one on 64// success or zero on error. 65OPENSSL_EXPORT int CMAC_Update(CMAC_CTX *ctx, const uint8_t *in, size_t in_len); 66 67// CMAC_Final sets |*out_len| to 16 and, if |out| is not NULL, writes 16 bytes 68// of authenticator to it. It returns one on success or zero on error. 69OPENSSL_EXPORT int CMAC_Final(CMAC_CTX *ctx, uint8_t *out, size_t *out_len); 70 71 72#if defined(__cplusplus) 73} // extern C 74 75extern "C++" { 76 77namespace bssl { 78 79BORINGSSL_MAKE_DELETER(CMAC_CTX, CMAC_CTX_free) 80 81} // namespace bssl 82 83} // extern C++ 84 85#endif 86 87#endif // OPENSSL_HEADER_CMAC_H 88