/** * \file cmac.c * * \brief NIST SP800-38B compliant CMAC implementation for AES and 3DES * * Copyright The Mbed TLS Contributors * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later */ /* * References: * * - NIST SP 800-38B Recommendation for Block Cipher Modes of Operation: The * CMAC Mode for Authentication * http://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-38b.pdf * * - RFC 4493 - The AES-CMAC Algorithm * https://tools.ietf.org/html/rfc4493 * * - RFC 4615 - The Advanced Encryption Standard-Cipher-based Message * Authentication Code-Pseudo-Random Function-128 (AES-CMAC-PRF-128) * Algorithm for the Internet Key Exchange Protocol (IKE) * https://tools.ietf.org/html/rfc4615 * * Additional test vectors: ISO/IEC 9797-1 * */ #include "common.h" #if defined(MBEDTLS_CMAC_C) #include "mbedtls/cmac.h" #include "mbedtls/platform_util.h" #include "mbedtls/error.h" #include "mbedtls/platform.h" #include #if !defined(MBEDTLS_CMAC_ALT) || defined(MBEDTLS_SELF_TEST) /* * Multiplication by u in the Galois field of GF(2^n) * * As explained in NIST SP 800-38B, this can be computed: * * If MSB(p) = 0, then p = (p << 1) * If MSB(p) = 1, then p = (p << 1) ^ R_n * with R_64 = 0x1B and R_128 = 0x87 * * Input and output MUST NOT point to the same buffer * Block size must be 8 bytes or 16 bytes - the block sizes for DES and AES. */ static int cmac_multiply_by_u(unsigned char *output, const unsigned char *input, size_t blocksize) { const unsigned char R_128 = 0x87; const unsigned char R_64 = 0x1B; unsigned char R_n, mask; unsigned char overflow = 0x00; int i; if (blocksize == MBEDTLS_AES_BLOCK_SIZE) { R_n = R_128; } else if (blocksize == MBEDTLS_DES3_BLOCK_SIZE) { R_n = R_64; } else { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } for (i = (int) blocksize - 1; i >= 0; i--) { output[i] = input[i] << 1 | overflow; overflow = input[i] >> 7; } /* mask = ( input[0] >> 7 ) ? 0xff : 0x00 * using bit operations to avoid branches */ /* MSVC has a warning about unary minus on unsigned, but this is * well-defined and precisely what we want to do here */ #if defined(_MSC_VER) #pragma warning( push ) #pragma warning( disable : 4146 ) #endif mask = -(input[0] >> 7); #if defined(_MSC_VER) #pragma warning( pop ) #endif output[blocksize - 1] ^= R_n & mask; return 0; } /* * Generate subkeys * * - as specified by RFC 4493, section 2.3 Subkey Generation Algorithm */ static int cmac_generate_subkeys(mbedtls_cipher_context_t *ctx, unsigned char *K1, unsigned char *K2) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; unsigned char L[MBEDTLS_CIPHER_BLKSIZE_MAX]; size_t olen, block_size; mbedtls_platform_zeroize(L, sizeof(L)); block_size = ctx->cipher_info->block_size; /* Calculate Ek(0) */ if ((ret = mbedtls_cipher_update(ctx, L, block_size, L, &olen)) != 0) { goto exit; } /* * Generate K1 and K2 */ if ((ret = cmac_multiply_by_u(K1, L, block_size)) != 0) { goto exit; } if ((ret = cmac_multiply_by_u(K2, K1, block_size)) != 0) { goto exit; } exit: mbedtls_platform_zeroize(L, sizeof(L)); return ret; } #endif /* !defined(MBEDTLS_CMAC_ALT) || defined(MBEDTLS_SELF_TEST) */ #if !defined(MBEDTLS_CMAC_ALT) static void cmac_xor_block(unsigned char *output, const unsigned char *input1, const unsigned char *input2, const size_t block_size) { size_t idx; for (idx = 0; idx < block_size; idx++) { output[idx] = input1[idx] ^ input2[idx]; } } /* * Create padded last block from (partial) last block. * * We can't use the padding option from the cipher layer, as it only works for * CBC and we use ECB mode, and anyway we need to XOR K1 or K2 in addition. */ static void cmac_pad(unsigned char padded_block[MBEDTLS_CIPHER_BLKSIZE_MAX], size_t padded_block_len, const unsigned char *last_block, size_t last_block_len) { size_t j; for (j = 0; j < padded_block_len; j++) { if (j < last_block_len) { padded_block[j] = last_block[j]; } else if (j == last_block_len) { padded_block[j] = 0x80; } else { padded_block[j] = 0x00; } } } int mbedtls_cipher_cmac_starts(mbedtls_cipher_context_t *ctx, const unsigned char *key, size_t keybits) { mbedtls_cipher_type_t type; mbedtls_cmac_context_t *cmac_ctx; int retval; if (ctx == NULL || ctx->cipher_info == NULL || key == NULL) { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } if ((retval = mbedtls_cipher_setkey(ctx, key, (int) keybits, MBEDTLS_ENCRYPT)) != 0) { return retval; } type = ctx->cipher_info->type; switch (type) { case MBEDTLS_CIPHER_AES_128_ECB: case MBEDTLS_CIPHER_AES_192_ECB: case MBEDTLS_CIPHER_AES_256_ECB: case MBEDTLS_CIPHER_DES_EDE3_ECB: break; default: return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } /* Allocated and initialise in the cipher context memory for the CMAC * context */ cmac_ctx = mbedtls_calloc(1, sizeof(mbedtls_cmac_context_t)); if (cmac_ctx == NULL) { return MBEDTLS_ERR_CIPHER_ALLOC_FAILED; } ctx->cmac_ctx = cmac_ctx; mbedtls_platform_zeroize(cmac_ctx->state, sizeof(cmac_ctx->state)); return 0; } int mbedtls_cipher_cmac_update(mbedtls_cipher_context_t *ctx, const unsigned char *input, size_t ilen) { mbedtls_cmac_context_t *cmac_ctx; unsigned char *state; int ret = 0; size_t n, j, olen, block_size; if (ctx == NULL || ctx->cipher_info == NULL || input == NULL || ctx->cmac_ctx == NULL) { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } cmac_ctx = ctx->cmac_ctx; block_size = ctx->cipher_info->block_size; state = ctx->cmac_ctx->state; /* Is there data still to process from the last call, that's greater in * size than a block? */ if (cmac_ctx->unprocessed_len > 0 && ilen > block_size - cmac_ctx->unprocessed_len) { memcpy(&cmac_ctx->unprocessed_block[cmac_ctx->unprocessed_len], input, block_size - cmac_ctx->unprocessed_len); cmac_xor_block(state, cmac_ctx->unprocessed_block, state, block_size); if ((ret = mbedtls_cipher_update(ctx, state, block_size, state, &olen)) != 0) { goto exit; } input += block_size - cmac_ctx->unprocessed_len; ilen -= block_size - cmac_ctx->unprocessed_len; cmac_ctx->unprocessed_len = 0; } /* n is the number of blocks including any final partial block */ n = (ilen + block_size - 1) / block_size; /* Iterate across the input data in block sized chunks, excluding any * final partial or complete block */ for (j = 1; j < n; j++) { cmac_xor_block(state, input, state, block_size); if ((ret = mbedtls_cipher_update(ctx, state, block_size, state, &olen)) != 0) { goto exit; } ilen -= block_size; input += block_size; } /* If there is data left over that wasn't aligned to a block */ if (ilen > 0) { memcpy(&cmac_ctx->unprocessed_block[cmac_ctx->unprocessed_len], input, ilen); cmac_ctx->unprocessed_len += ilen; } exit: return ret; } int mbedtls_cipher_cmac_finish(mbedtls_cipher_context_t *ctx, unsigned char *output) { mbedtls_cmac_context_t *cmac_ctx; unsigned char *state, *last_block; unsigned char K1[MBEDTLS_CIPHER_BLKSIZE_MAX]; unsigned char K2[MBEDTLS_CIPHER_BLKSIZE_MAX]; unsigned char M_last[MBEDTLS_CIPHER_BLKSIZE_MAX]; int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t olen, block_size; if (ctx == NULL || ctx->cipher_info == NULL || ctx->cmac_ctx == NULL || output == NULL) { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } cmac_ctx = ctx->cmac_ctx; block_size = ctx->cipher_info->block_size; state = cmac_ctx->state; mbedtls_platform_zeroize(K1, sizeof(K1)); mbedtls_platform_zeroize(K2, sizeof(K2)); cmac_generate_subkeys(ctx, K1, K2); last_block = cmac_ctx->unprocessed_block; /* Calculate last block */ if (cmac_ctx->unprocessed_len < block_size) { cmac_pad(M_last, block_size, last_block, cmac_ctx->unprocessed_len); cmac_xor_block(M_last, M_last, K2, block_size); } else { /* Last block is complete block */ cmac_xor_block(M_last, last_block, K1, block_size); } cmac_xor_block(state, M_last, state, block_size); if ((ret = mbedtls_cipher_update(ctx, state, block_size, state, &olen)) != 0) { goto exit; } memcpy(output, state, block_size); exit: /* Wipe the generated keys on the stack, and any other transients to avoid * side channel leakage */ mbedtls_platform_zeroize(K1, sizeof(K1)); mbedtls_platform_zeroize(K2, sizeof(K2)); cmac_ctx->unprocessed_len = 0; mbedtls_platform_zeroize(cmac_ctx->unprocessed_block, sizeof(cmac_ctx->unprocessed_block)); mbedtls_platform_zeroize(state, MBEDTLS_CIPHER_BLKSIZE_MAX); return ret; } int mbedtls_cipher_cmac_reset(mbedtls_cipher_context_t *ctx) { mbedtls_cmac_context_t *cmac_ctx; if (ctx == NULL || ctx->cipher_info == NULL || ctx->cmac_ctx == NULL) { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } cmac_ctx = ctx->cmac_ctx; /* Reset the internal state */ cmac_ctx->unprocessed_len = 0; mbedtls_platform_zeroize(cmac_ctx->unprocessed_block, sizeof(cmac_ctx->unprocessed_block)); mbedtls_platform_zeroize(cmac_ctx->state, sizeof(cmac_ctx->state)); return 0; } int mbedtls_cipher_cmac(const mbedtls_cipher_info_t *cipher_info, const unsigned char *key, size_t keylen, const unsigned char *input, size_t ilen, unsigned char *output) { mbedtls_cipher_context_t ctx; int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; if (cipher_info == NULL || key == NULL || input == NULL || output == NULL) { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } mbedtls_cipher_init(&ctx); if ((ret = mbedtls_cipher_setup(&ctx, cipher_info)) != 0) { goto exit; } ret = mbedtls_cipher_cmac_starts(&ctx, key, keylen); if (ret != 0) { goto exit; } ret = mbedtls_cipher_cmac_update(&ctx, input, ilen); if (ret != 0) { goto exit; } ret = mbedtls_cipher_cmac_finish(&ctx, output); exit: mbedtls_cipher_free(&ctx); return ret; } #if defined(MBEDTLS_AES_C) /* * Implementation of AES-CMAC-PRF-128 defined in RFC 4615 */ int mbedtls_aes_cmac_prf_128(const unsigned char *key, size_t key_length, const unsigned char *input, size_t in_len, unsigned char output[16]) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; const mbedtls_cipher_info_t *cipher_info; unsigned char zero_key[MBEDTLS_AES_BLOCK_SIZE]; unsigned char int_key[MBEDTLS_AES_BLOCK_SIZE]; if (key == NULL || input == NULL || output == NULL) { return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA; } cipher_info = mbedtls_cipher_info_from_type(MBEDTLS_CIPHER_AES_128_ECB); if (cipher_info == NULL) { /* Failing at this point must be due to a build issue */ ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE; goto exit; } if (key_length == MBEDTLS_AES_BLOCK_SIZE) { /* Use key as is */ memcpy(int_key, key, MBEDTLS_AES_BLOCK_SIZE); } else { memset(zero_key, 0, MBEDTLS_AES_BLOCK_SIZE); ret = mbedtls_cipher_cmac(cipher_info, zero_key, 128, key, key_length, int_key); if (ret != 0) { goto exit; } } ret = mbedtls_cipher_cmac(cipher_info, int_key, 128, input, in_len, output); exit: mbedtls_platform_zeroize(int_key, sizeof(int_key)); return ret; } #endif /* MBEDTLS_AES_C */ #endif /* !MBEDTLS_CMAC_ALT */ #if defined(MBEDTLS_SELF_TEST) /* * CMAC test data for SP800-38B * http://csrc.nist.gov/groups/ST/toolkit/documents/Examples/AES_CMAC.pdf * http://csrc.nist.gov/groups/ST/toolkit/documents/Examples/TDES_CMAC.pdf * * AES-CMAC-PRF-128 test data from RFC 4615 * https://tools.ietf.org/html/rfc4615#page-4 */ #define NB_CMAC_TESTS_PER_KEY 4 #define NB_PRF_TESTS 3 #if defined(MBEDTLS_AES_C) || defined(MBEDTLS_DES_C) /* All CMAC test inputs are truncated from the same 64 byte buffer. */ static const unsigned char test_message[] = { /* PT */ 0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96, 0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a, 0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c, 0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51, 0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11, 0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef, 0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 }; #endif /* MBEDTLS_AES_C || MBEDTLS_DES_C */ #if defined(MBEDTLS_AES_C) /* Truncation point of message for AES CMAC tests */ static const unsigned int aes_message_lengths[NB_CMAC_TESTS_PER_KEY] = { /* Mlen */ 0, 16, 20, 64 }; /* CMAC-AES128 Test Data */ static const unsigned char aes_128_key[16] = { 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6, 0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c }; static const unsigned char aes_128_subkeys[2][MBEDTLS_AES_BLOCK_SIZE] = { { /* K1 */ 0xfb, 0xee, 0xd6, 0x18, 0x35, 0x71, 0x33, 0x66, 0x7c, 0x85, 0xe0, 0x8f, 0x72, 0x36, 0xa8, 0xde }, { /* K2 */ 0xf7, 0xdd, 0xac, 0x30, 0x6a, 0xe2, 0x66, 0xcc, 0xf9, 0x0b, 0xc1, 0x1e, 0xe4, 0x6d, 0x51, 0x3b } }; static const unsigned char aes_128_expected_result[NB_CMAC_TESTS_PER_KEY][MBEDTLS_AES_BLOCK_SIZE] = { { /* Example #1 */ 0xbb, 0x1d, 0x69, 0x29, 0xe9, 0x59, 0x37, 0x28, 0x7f, 0xa3, 0x7d, 0x12, 0x9b, 0x75, 0x67, 0x46 }, { /* Example #2 */ 0x07, 0x0a, 0x16, 0xb4, 0x6b, 0x4d, 0x41, 0x44, 0xf7, 0x9b, 0xdd, 0x9d, 0xd0, 0x4a, 0x28, 0x7c }, { /* Example #3 */ 0x7d, 0x85, 0x44, 0x9e, 0xa6, 0xea, 0x19, 0xc8, 0x23, 0xa7, 0xbf, 0x78, 0x83, 0x7d, 0xfa, 0xde }, { /* Example #4 */ 0x51, 0xf0, 0xbe, 0xbf, 0x7e, 0x3b, 0x9d, 0x92, 0xfc, 0x49, 0x74, 0x17, 0x79, 0x36, 0x3c, 0xfe } }; /* CMAC-AES192 Test Data */ static const unsigned char aes_192_key[24] = { 0x8e, 0x73, 0xb0, 0xf7, 0xda, 0x0e, 0x64, 0x52, 0xc8, 0x10, 0xf3, 0x2b, 0x80, 0x90, 0x79, 0xe5, 0x62, 0xf8, 0xea, 0xd2, 0x52, 0x2c, 0x6b, 0x7b }; static const unsigned char aes_192_subkeys[2][MBEDTLS_AES_BLOCK_SIZE] = { { /* K1 */ 0x44, 0x8a, 0x5b, 0x1c, 0x93, 0x51, 0x4b, 0x27, 0x3e, 0xe6, 0x43, 0x9d, 0xd4, 0xda, 0xa2, 0x96 }, { /* K2 */ 0x89, 0x14, 0xb6, 0x39, 0x26, 0xa2, 0x96, 0x4e, 0x7d, 0xcc, 0x87, 0x3b, 0xa9, 0xb5, 0x45, 0x2c } }; static const unsigned char aes_192_expected_result[NB_CMAC_TESTS_PER_KEY][MBEDTLS_AES_BLOCK_SIZE] = { { /* Example #1 */ 0xd1, 0x7d, 0xdf, 0x46, 0xad, 0xaa, 0xcd, 0xe5, 0x31, 0xca, 0xc4, 0x83, 0xde, 0x7a, 0x93, 0x67 }, { /* Example #2 */ 0x9e, 0x99, 0xa7, 0xbf, 0x31, 0xe7, 0x10, 0x90, 0x06, 0x62, 0xf6, 0x5e, 0x61, 0x7c, 0x51, 0x84 }, { /* Example #3 */ 0x3d, 0x75, 0xc1, 0x94, 0xed, 0x96, 0x07, 0x04, 0x44, 0xa9, 0xfa, 0x7e, 0xc7, 0x40, 0xec, 0xf8 }, { /* Example #4 */ 0xa1, 0xd5, 0xdf, 0x0e, 0xed, 0x79, 0x0f, 0x79, 0x4d, 0x77, 0x58, 0x96, 0x59, 0xf3, 0x9a, 0x11 } }; /* CMAC-AES256 Test Data */ static const unsigned char aes_256_key[32] = { 0x60, 0x3d, 0xeb, 0x10, 0x15, 0xca, 0x71, 0xbe, 0x2b, 0x73, 0xae, 0xf0, 0x85, 0x7d, 0x77, 0x81, 0x1f, 0x35, 0x2c, 0x07, 0x3b, 0x61, 0x08, 0xd7, 0x2d, 0x98, 0x10, 0xa3, 0x09, 0x14, 0xdf, 0xf4 }; static const unsigned char aes_256_subkeys[2][MBEDTLS_AES_BLOCK_SIZE] = { { /* K1 */ 0xca, 0xd1, 0xed, 0x03, 0x29, 0x9e, 0xed, 0xac, 0x2e, 0x9a, 0x99, 0x80, 0x86, 0x21, 0x50, 0x2f }, { /* K2 */ 0x95, 0xa3, 0xda, 0x06, 0x53, 0x3d, 0xdb, 0x58, 0x5d, 0x35, 0x33, 0x01, 0x0c, 0x42, 0xa0, 0xd9 } }; static const unsigned char aes_256_expected_result[NB_CMAC_TESTS_PER_KEY][MBEDTLS_AES_BLOCK_SIZE] = { { /* Example #1 */ 0x02, 0x89, 0x62, 0xf6, 0x1b, 0x7b, 0xf8, 0x9e, 0xfc, 0x6b, 0x55, 0x1f, 0x46, 0x67, 0xd9, 0x83 }, { /* Example #2 */ 0x28, 0xa7, 0x02, 0x3f, 0x45, 0x2e, 0x8f, 0x82, 0xbd, 0x4b, 0xf2, 0x8d, 0x8c, 0x37, 0xc3, 0x5c }, { /* Example #3 */ 0x15, 0x67, 0x27, 0xdc, 0x08, 0x78, 0x94, 0x4a, 0x02, 0x3c, 0x1f, 0xe0, 0x3b, 0xad, 0x6d, 0x93 }, { /* Example #4 */ 0xe1, 0x99, 0x21, 0x90, 0x54, 0x9f, 0x6e, 0xd5, 0x69, 0x6a, 0x2c, 0x05, 0x6c, 0x31, 0x54, 0x10 } }; #endif /* MBEDTLS_AES_C */ #if defined(MBEDTLS_DES_C) /* Truncation point of message for 3DES CMAC tests */ static const unsigned int des3_message_lengths[NB_CMAC_TESTS_PER_KEY] = { 0, 16, 20, 32 }; /* CMAC-TDES (Generation) - 2 Key Test Data */ static const unsigned char des3_2key_key[24] = { /* Key1 */ 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, /* Key2 */ 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xEF, 0x01, /* Key3 */ 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef }; static const unsigned char des3_2key_subkeys[2][8] = { { /* K1 */ 0x0d, 0xd2, 0xcb, 0x7a, 0x3d, 0x88, 0x88, 0xd9 }, { /* K2 */ 0x1b, 0xa5, 0x96, 0xf4, 0x7b, 0x11, 0x11, 0xb2 } }; static const unsigned char des3_2key_expected_result[NB_CMAC_TESTS_PER_KEY][MBEDTLS_DES3_BLOCK_SIZE] = { { /* Sample #1 */ 0x79, 0xce, 0x52, 0xa7, 0xf7, 0x86, 0xa9, 0x60 }, { /* Sample #2 */ 0xcc, 0x18, 0xa0, 0xb7, 0x9a, 0xf2, 0x41, 0x3b }, { /* Sample #3 */ 0xc0, 0x6d, 0x37, 0x7e, 0xcd, 0x10, 0x19, 0x69 }, { /* Sample #4 */ 0x9c, 0xd3, 0x35, 0x80, 0xf9, 0xb6, 0x4d, 0xfb } }; /* CMAC-TDES (Generation) - 3 Key Test Data */ static const unsigned char des3_3key_key[24] = { /* Key1 */ 0x01, 0x23, 0x45, 0x67, 0x89, 0xaa, 0xcd, 0xef, /* Key2 */ 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0x01, /* Key3 */ 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0x01, 0x23 }; static const unsigned char des3_3key_subkeys[2][8] = { { /* K1 */ 0x9d, 0x74, 0xe7, 0x39, 0x33, 0x17, 0x96, 0xc0 }, { /* K2 */ 0x3a, 0xe9, 0xce, 0x72, 0x66, 0x2f, 0x2d, 0x9b } }; static const unsigned char des3_3key_expected_result[NB_CMAC_TESTS_PER_KEY][MBEDTLS_DES3_BLOCK_SIZE] = { { /* Sample #1 */ 0x7d, 0xb0, 0xd3, 0x7d, 0xf9, 0x36, 0xc5, 0x50 }, { /* Sample #2 */ 0x30, 0x23, 0x9c, 0xf1, 0xf5, 0x2e, 0x66, 0x09 }, { /* Sample #3 */ 0x6c, 0x9f, 0x3e, 0xe4, 0x92, 0x3f, 0x6b, 0xe2 }, { /* Sample #4 */ 0x99, 0x42, 0x9b, 0xd0, 0xbF, 0x79, 0x04, 0xe5 } }; #endif /* MBEDTLS_DES_C */ #if defined(MBEDTLS_AES_C) /* AES AES-CMAC-PRF-128 Test Data */ static const unsigned char PRFK[] = { /* Key */ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0xed, 0xcb }; /* Sizes in bytes */ static const size_t PRFKlen[NB_PRF_TESTS] = { 18, 16, 10 }; /* Message */ static const unsigned char PRFM[] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13 }; static const unsigned char PRFT[NB_PRF_TESTS][16] = { { 0x84, 0xa3, 0x48, 0xa4, 0xa4, 0x5d, 0x23, 0x5b, 0xab, 0xff, 0xfc, 0x0d, 0x2b, 0x4d, 0xa0, 0x9a }, { 0x98, 0x0a, 0xe8, 0x7b, 0x5f, 0x4c, 0x9c, 0x52, 0x14, 0xf5, 0xb6, 0xa8, 0x45, 0x5e, 0x4c, 0x2d }, { 0x29, 0x0d, 0x9e, 0x11, 0x2e, 0xdb, 0x09, 0xee, 0x14, 0x1f, 0xcf, 0x64, 0xc0, 0xb7, 0x2f, 0x3d } }; #endif /* MBEDTLS_AES_C */ static int cmac_test_subkeys(int verbose, const char *testname, const unsigned char *key, int keybits, const unsigned char *subkeys, mbedtls_cipher_type_t cipher_type, int block_size, int num_tests) { int i, ret = 0; mbedtls_cipher_context_t ctx; const mbedtls_cipher_info_t *cipher_info; unsigned char K1[MBEDTLS_CIPHER_BLKSIZE_MAX]; unsigned char K2[MBEDTLS_CIPHER_BLKSIZE_MAX]; cipher_info = mbedtls_cipher_info_from_type(cipher_type); if (cipher_info == NULL) { /* Failing at this point must be due to a build issue */ return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE; } for (i = 0; i < num_tests; i++) { if (verbose != 0) { mbedtls_printf(" %s CMAC subkey #%d: ", testname, i + 1); } mbedtls_cipher_init(&ctx); if ((ret = mbedtls_cipher_setup(&ctx, cipher_info)) != 0) { if (verbose != 0) { mbedtls_printf("test execution failed\n"); } goto cleanup; } if ((ret = mbedtls_cipher_setkey(&ctx, key, keybits, MBEDTLS_ENCRYPT)) != 0) { /* When CMAC is implemented by an alternative implementation, or * the underlying primitive itself is implemented alternatively, * AES-192 may be unavailable. This should not cause the selftest * function to fail. */ if ((ret == MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED || ret == MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE) && cipher_type == MBEDTLS_CIPHER_AES_192_ECB) { if (verbose != 0) { mbedtls_printf("skipped\n"); } goto next_test; } if (verbose != 0) { mbedtls_printf("test execution failed\n"); } goto cleanup; } ret = cmac_generate_subkeys(&ctx, K1, K2); if (ret != 0) { if (verbose != 0) { mbedtls_printf("failed\n"); } goto cleanup; } if ((ret = memcmp(K1, subkeys, block_size)) != 0 || (ret = memcmp(K2, &subkeys[block_size], block_size)) != 0) { if (verbose != 0) { mbedtls_printf("failed\n"); } goto cleanup; } if (verbose != 0) { mbedtls_printf("passed\n"); } next_test: mbedtls_cipher_free(&ctx); } ret = 0; goto exit; cleanup: mbedtls_cipher_free(&ctx); exit: return ret; } static int cmac_test_wth_cipher(int verbose, const char *testname, const unsigned char *key, int keybits, const unsigned char *messages, const unsigned int message_lengths[4], const unsigned char *expected_result, mbedtls_cipher_type_t cipher_type, int block_size, int num_tests) { const mbedtls_cipher_info_t *cipher_info; int i, ret = 0; unsigned char output[MBEDTLS_CIPHER_BLKSIZE_MAX]; cipher_info = mbedtls_cipher_info_from_type(cipher_type); if (cipher_info == NULL) { /* Failing at this point must be due to a build issue */ ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE; goto exit; } for (i = 0; i < num_tests; i++) { if (verbose != 0) { mbedtls_printf(" %s CMAC #%d: ", testname, i + 1); } if ((ret = mbedtls_cipher_cmac(cipher_info, key, keybits, messages, message_lengths[i], output)) != 0) { /* When CMAC is implemented by an alternative implementation, or * the underlying primitive itself is implemented alternatively, * AES-192 and/or 3DES may be unavailable. This should not cause * the selftest function to fail. */ if ((ret == MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED || ret == MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE) && (cipher_type == MBEDTLS_CIPHER_AES_192_ECB || cipher_type == MBEDTLS_CIPHER_DES_EDE3_ECB)) { if (verbose != 0) { mbedtls_printf("skipped\n"); } continue; } if (verbose != 0) { mbedtls_printf("failed\n"); } goto exit; } if ((ret = memcmp(output, &expected_result[i * block_size], block_size)) != 0) { if (verbose != 0) { mbedtls_printf("failed\n"); } goto exit; } if (verbose != 0) { mbedtls_printf("passed\n"); } } ret = 0; exit: return ret; } #if defined(MBEDTLS_AES_C) static int test_aes128_cmac_prf(int verbose) { int i; int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; unsigned char output[MBEDTLS_AES_BLOCK_SIZE]; for (i = 0; i < NB_PRF_TESTS; i++) { mbedtls_printf(" AES CMAC 128 PRF #%d: ", i); ret = mbedtls_aes_cmac_prf_128(PRFK, PRFKlen[i], PRFM, 20, output); if (ret != 0 || memcmp(output, PRFT[i], MBEDTLS_AES_BLOCK_SIZE) != 0) { if (verbose != 0) { mbedtls_printf("failed\n"); } return ret; } else if (verbose != 0) { mbedtls_printf("passed\n"); } } return ret; } #endif /* MBEDTLS_AES_C */ int mbedtls_cmac_self_test(int verbose) { int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; #if defined(MBEDTLS_AES_C) /* AES-128 */ if ((ret = cmac_test_subkeys(verbose, "AES 128", aes_128_key, 128, (const unsigned char *) aes_128_subkeys, MBEDTLS_CIPHER_AES_128_ECB, MBEDTLS_AES_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } if ((ret = cmac_test_wth_cipher(verbose, "AES 128", aes_128_key, 128, test_message, aes_message_lengths, (const unsigned char *) aes_128_expected_result, MBEDTLS_CIPHER_AES_128_ECB, MBEDTLS_AES_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } /* AES-192 */ if ((ret = cmac_test_subkeys(verbose, "AES 192", aes_192_key, 192, (const unsigned char *) aes_192_subkeys, MBEDTLS_CIPHER_AES_192_ECB, MBEDTLS_AES_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } if ((ret = cmac_test_wth_cipher(verbose, "AES 192", aes_192_key, 192, test_message, aes_message_lengths, (const unsigned char *) aes_192_expected_result, MBEDTLS_CIPHER_AES_192_ECB, MBEDTLS_AES_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } /* AES-256 */ if ((ret = cmac_test_subkeys(verbose, "AES 256", aes_256_key, 256, (const unsigned char *) aes_256_subkeys, MBEDTLS_CIPHER_AES_256_ECB, MBEDTLS_AES_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } if ((ret = cmac_test_wth_cipher(verbose, "AES 256", aes_256_key, 256, test_message, aes_message_lengths, (const unsigned char *) aes_256_expected_result, MBEDTLS_CIPHER_AES_256_ECB, MBEDTLS_AES_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } #endif /* MBEDTLS_AES_C */ #if defined(MBEDTLS_DES_C) /* 3DES 2 key */ if ((ret = cmac_test_subkeys(verbose, "3DES 2 key", des3_2key_key, 192, (const unsigned char *) des3_2key_subkeys, MBEDTLS_CIPHER_DES_EDE3_ECB, MBEDTLS_DES3_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } if ((ret = cmac_test_wth_cipher(verbose, "3DES 2 key", des3_2key_key, 192, test_message, des3_message_lengths, (const unsigned char *) des3_2key_expected_result, MBEDTLS_CIPHER_DES_EDE3_ECB, MBEDTLS_DES3_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } /* 3DES 3 key */ if ((ret = cmac_test_subkeys(verbose, "3DES 3 key", des3_3key_key, 192, (const unsigned char *) des3_3key_subkeys, MBEDTLS_CIPHER_DES_EDE3_ECB, MBEDTLS_DES3_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } if ((ret = cmac_test_wth_cipher(verbose, "3DES 3 key", des3_3key_key, 192, test_message, des3_message_lengths, (const unsigned char *) des3_3key_expected_result, MBEDTLS_CIPHER_DES_EDE3_ECB, MBEDTLS_DES3_BLOCK_SIZE, NB_CMAC_TESTS_PER_KEY)) != 0) { return ret; } #endif /* MBEDTLS_DES_C */ #if defined(MBEDTLS_AES_C) if ((ret = test_aes128_cmac_prf(verbose)) != 0) { return ret; } #endif /* MBEDTLS_AES_C */ if (verbose != 0) { mbedtls_printf("\n"); } return 0; } #endif /* MBEDTLS_SELF_TEST */ #endif /* MBEDTLS_CMAC_C */