+/*
+ * AES-CMAC from NIST Special Publication 800-38B \97 Recommendation for block cipher modes of operation: The CMAC mode for authentication.
+ *
+ * Copyright (C) 2006-2014, Brainspark B.V.
+ * Copyright (C) 2014, Anargyros Plemenos
+ * Tests added Merkok, 2018
+ *
+ * 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.
+ *
+ * Reference : https://polarssl.org/discussions/generic/authentication-token
+ * NIST Special Publication 800-38B \97 Recommendation for block cipher modes of operation: The CMAC mode for authentication.
+ * Tests here:
+ * https://csrc.nist.gov/CSRC/media/Projects/Cryptographic-Standards-and-Guidelines/documents/examples/AES_CMAC.pdf
+*/
+
+#include "polarssl/aes_cmac128.h"
+#include <stdio.h>
+
+#define MIN(a,b) ((a)<(b)?(a):(b))
+#define _MSB(x) (((x)[0] & 0x80)?1:0)
+
+#if !defined(POLARSSL_CONFIG_FILE)
+#include "polarssl_config.h"
+#else
+#include POLARSSL_CONFIG_FILE
+#endif
+
+#if defined(POLARSSL_AES_C)
+#include "aes.h"
+#endif
+
+#if defined(POLARSSL_PLATFORM_C)
+#include "polarssl/platform.h"
+#else
+#define polarssl_printf printf
+#endif
+
+
+/**
+ * zero a structure
+ */
+#define ZERO_STRUCT(x) memset((char *)&(x), 0, sizeof(x))
+
+/**
+ * zero a structure given a pointer to the structure
+ */
+#define ZERO_STRUCTP(x) do{ if((x) != NULL) memset((char *)(x), 0, sizeof(*(x)));} while(0)
+
+
+/* For CMAC Calculation */
+static unsigned char const_Rb[16] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x87
+};
+static unsigned char const_Zero[16] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+};
+
+static inline void aes_cmac_128_left_shift_1(const uint8_t in[16], uint8_t out[16])
+{
+ uint8_t overflow = 0;
+ int8_t i;
+
+ for (i = 15; i >= 0; i--) {
+ out[i] = in[i] << 1;
+ out[i] |= overflow;
+ overflow = _MSB(&in[i]);
+ }
+}
+
+static inline void aes_cmac_128_xor(const uint8_t in1[16], const uint8_t in2[16],
+ uint8_t out[16])
+{
+ uint8_t i;
+
+ for (i = 0; i < 16; i++) {
+ out[i] = in1[i] ^ in2[i];
+ }
+}
+
+/*
+ * AES-CMAC-128 context setup
+ */
+void aes_cmac128_starts(aes_cmac128_context *ctx, const uint8_t K[16])
+{
+ uint8_t L[16];
+
+ /* Zero struct of aes_context */
+ ZERO_STRUCTP(ctx);
+ /* Initialize aes_context */
+ aes_setkey_enc(&ctx->aes_key, K, 128);
+
+ /* step 1 - generate subkeys k1 and k2 */
+ aes_crypt_ecb(&ctx->aes_key, AES_ENCRYPT, const_Zero, L);
+
+ if (_MSB(L) == 0) {
+ aes_cmac_128_left_shift_1(L, ctx->K1);
+ } else {
+ uint8_t tmp_block[16];
+
+ aes_cmac_128_left_shift_1(L, tmp_block);
+ aes_cmac_128_xor(tmp_block, const_Rb, ctx->K1);
+ ZERO_STRUCT(tmp_block);
+ }
+
+ if (_MSB(ctx->K1) == 0) {
+ aes_cmac_128_left_shift_1(ctx->K1, ctx->K2);
+ } else {
+ uint8_t tmp_block[16];
+
+ aes_cmac_128_left_shift_1(ctx->K1, tmp_block);
+ aes_cmac_128_xor(tmp_block, const_Rb, ctx->K2);
+ ZERO_STRUCT(tmp_block);
+ }
+
+ ZERO_STRUCT(L);
+}
+
+/*
+ * AES-CMAC-128 process message
+ */
+void aes_cmac128_update(aes_cmac128_context *ctx, const uint8_t *_msg, size_t _msg_len)
+{
+ uint8_t tmp_block[16];
+ uint8_t Y[16];
+ const uint8_t *msg = _msg;
+ size_t msg_len = _msg_len;
+
+ /*
+ * copy the remembered last block
+ */
+ ZERO_STRUCT(tmp_block);
+ if (ctx->last_len) {
+ memcpy(tmp_block, ctx->last, ctx->last_len);
+ }
+
+ /*
+ * check if we expand the block
+ */
+ if (ctx->last_len < 16) {
+ size_t len = MIN(16 - ctx->last_len, msg_len);
+
+ memcpy(&tmp_block[ctx->last_len], msg, len);
+ memcpy(ctx->last, tmp_block, 16);
+ msg += len;
+ msg_len -= len;
+ ctx->last_len += len;
+ }
+
+ if (msg_len == 0) {
+ /* if it is still the last block, we are done */
+ ZERO_STRUCT(tmp_block);
+ return;
+ }
+
+ /*
+ * It is not the last block anymore
+ */
+ ZERO_STRUCT(ctx->last);
+ ctx->last_len = 0;
+
+ /*
+ * now checksum everything but the last block
+ */
+ aes_cmac_128_xor(ctx->X, tmp_block, Y);
+ aes_crypt_ecb(&ctx->aes_key, AES_ENCRYPT, Y, ctx->X);
+
+ while (msg_len > 16) {
+ memcpy(tmp_block, msg, 16);
+ msg += 16;
+ msg_len -= 16;
+
+ aes_cmac_128_xor(ctx->X, tmp_block, Y);
+ aes_crypt_ecb(&ctx->aes_key, AES_ENCRYPT, Y, ctx->X);
+ }
+
+ /*
+ * copy the last block, it will be processed in
+ * aes_cmac128_final().
+ */
+ memcpy(ctx->last, msg, msg_len);
+ ctx->last_len = msg_len;
+
+ ZERO_STRUCT(tmp_block);
+ ZERO_STRUCT(Y);
+}
+
+/*
+ * AES-CMAC-128 compute T
+ */
+void aes_cmac128_final(aes_cmac128_context *ctx, uint8_t T[16])
+{
+ uint8_t tmp_block[16];
+ uint8_t Y[16];
+
+ if (ctx->last_len < 16) {
+ ctx->last[ctx->last_len] = 0x80;
+ aes_cmac_128_xor(ctx->last, ctx->K2, tmp_block);
+ } else {
+ aes_cmac_128_xor(ctx->last, ctx->K1, tmp_block);
+ }
+
+ aes_cmac_128_xor(tmp_block, ctx->X, Y);
+ aes_crypt_ecb(&ctx->aes_key, AES_ENCRYPT, Y, T);
+
+ ZERO_STRUCT(tmp_block);
+ ZERO_STRUCT(Y);
+ ZERO_STRUCTP(ctx);
+}
+
+/*
+ * Checkup routine
+ *
+ * https://csrc.nist.gov/projects/cryptographic-standards-and-guidelines/example-values
+ * https://csrc.nist.gov/CSRC/media/Projects/Cryptographic-Standards-and-Guidelines/documents/examples/AES_CMAC.pdf
+ */
+int aes_cmac_self_test( int verbose )
+{
+ unsigned char key[16] = {0x2B, 0x7E, 0x15, 0x16, 0x28, 0xAE, 0xD2, 0xA6, 0xAB, 0xF7, 0x15, 0x88, 0x09, 0xCF, 0x4F, 0x3C};
+ unsigned char mac[16] = {0};
+ aes_cmac128_context ctx;
+ int ret;
+
+ // check Example1:
+ if( verbose != 0 )
+ polarssl_printf( " AES-CMAC-128 zero length data: " );
+ unsigned char ex1data[16] = {0};
+ aes_cmac128_starts(&ctx, key);
+ aes_cmac128_update(&ctx, ex1data, 0);
+ aes_cmac128_final(&ctx, mac);
+ unsigned char ex1res[16] = {0xBB, 0x1D, 0x69, 0x29, 0xE9, 0x59, 0x37, 0x28, 0x7F, 0xA3, 0x7D, 0x12, 0x9B, 0x75, 0x67, 0x46};
+ if(!memcmp(mac, ex1res, 16)) {
+ if( verbose != 0 )
+ polarssl_printf( "passed\n" );
+ } else {
+ polarssl_printf( "failed\n" );
+ ret = 1;
+ goto exit;
+ }
+
+ // check Example2:
+ if( verbose != 0 )
+ polarssl_printf( " AES-CMAC-128 one block data : " );
+ unsigned char ex2data[16] = {0x6B, 0xC1, 0xBE, 0xE2, 0x2E, 0x40, 0x9F, 0x96, 0xE9, 0x3D, 0x7E, 0x11, 0x73, 0x93, 0x17, 0x2A};
+ aes_cmac128_starts(&ctx, key);
+ aes_cmac128_update(&ctx, ex2data, sizeof(ex2data));
+ aes_cmac128_final(&ctx, mac);
+ unsigned char ex2res[16] = {0x07, 0x0A, 0x16, 0xB4, 0x6B, 0x4D, 0x41, 0x44, 0xF7, 0x9B, 0xDD, 0x9D, 0xD0, 0x4A, 0x28, 0x7C};
+ if(!memcmp(mac, ex2res, 16)) {
+ if( verbose != 0 )
+ polarssl_printf( "passed\n" );
+ } else {
+ polarssl_printf( "failed\n" );
+ ret = 1;
+ goto exit;
+ }
+
+ // check Example3:
+ if( verbose != 0 )
+ polarssl_printf( " AES-CMAC-128 20 bytes of data: " );
+ unsigned char ex3data[20] = {0x6B, 0xC1, 0xBE, 0xE2, 0x2E, 0x40, 0x9F, 0x96, 0xE9, 0x3D, 0x7E, 0x11, 0x73, 0x93, 0x17, 0x2A,
+ 0xAE, 0x2D, 0x8A, 0x57};
+ aes_cmac128_starts(&ctx, key);
+ aes_cmac128_update(&ctx, ex3data, sizeof(ex3data));
+ aes_cmac128_final(&ctx, mac);
+ unsigned char ex3res[16] = {0x7D, 0x85, 0x44, 0x9E, 0xA6, 0xEA, 0x19, 0xC8, 0x23, 0xA7, 0xBF, 0x78, 0x83, 0x7D, 0xFA, 0xDE};
+ if(!memcmp(mac, ex3res, 16)) {
+ if( verbose != 0 )
+ polarssl_printf( "passed\n" );
+ } else {
+ polarssl_printf( "failed\n" );
+ ret = 1;
+ goto exit;
+ }
+
+ // check Example4:
+ if( verbose != 0 )
+ polarssl_printf( " AES-CMAC-128 4 blocks of data: " );
+ unsigned char ex4data[64] = {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};
+ aes_cmac128_starts(&ctx, key);
+ aes_cmac128_update(&ctx, ex4data, sizeof(ex4data));
+ aes_cmac128_final(&ctx, mac);
+ unsigned char ex4res[16] = {0x51, 0xF0, 0xBE, 0xBF, 0x7E, 0x3B, 0x9D, 0x92, 0xFC, 0x49, 0x74, 0x17, 0x79, 0x36, 0x3C, 0xFE};
+ if(!memcmp(mac, ex4res, 16)) {
+ if( verbose != 0 )
+ polarssl_printf( "passed\n" );
+ } else {
+ polarssl_printf( "failed\n" );
+ ret = 1;
+ goto exit;
+ }
+
+ if( verbose != 0 )
+ polarssl_printf( "\n" );
+
+ ret = 0;
+
+exit:
+ return( ret );
+}
+
projects / proxmark3-svn / commitdiff