Timothy Beight / Mbed 2 deprecated 6_songs-from-the-cloud

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Dependencies:   mbed Socket lwip-eth lwip-sys lwip

Fork of 6_songs-from-the-cloud by MakingMusicWorkshop

mbed-client/mbedtls/source/hmac_drbg.c@0:f7c60d3e7b8a, 2016-05-18 (annotated)

Committer:
maclobdell
Date:
Wed May 18 19:06:32 2016 +0000
Revision:
0:f7c60d3e7b8a
clean version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
maclobdell 0:f7c60d3e7b8a 1 /*
maclobdell 0:f7c60d3e7b8a 2 * HMAC_DRBG implementation (NIST SP 800-90)
maclobdell 0:f7c60d3e7b8a 3 *
maclobdell 0:f7c60d3e7b8a 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
maclobdell 0:f7c60d3e7b8a 5 * SPDX-License-Identifier: Apache-2.0
maclobdell 0:f7c60d3e7b8a 6 *
maclobdell 0:f7c60d3e7b8a 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
maclobdell 0:f7c60d3e7b8a 8 * not use this file except in compliance with the License.
maclobdell 0:f7c60d3e7b8a 9 * You may obtain a copy of the License at
maclobdell 0:f7c60d3e7b8a 10 *
maclobdell 0:f7c60d3e7b8a 11 * http://www.apache.org/licenses/LICENSE-2.0
maclobdell 0:f7c60d3e7b8a 12 *
maclobdell 0:f7c60d3e7b8a 13 * Unless required by applicable law or agreed to in writing, software
maclobdell 0:f7c60d3e7b8a 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
maclobdell 0:f7c60d3e7b8a 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
maclobdell 0:f7c60d3e7b8a 16 * See the License for the specific language governing permissions and
maclobdell 0:f7c60d3e7b8a 17 * limitations under the License.
maclobdell 0:f7c60d3e7b8a 18 *
maclobdell 0:f7c60d3e7b8a 19 * This file is part of mbed TLS (https://tls.mbed.org)
maclobdell 0:f7c60d3e7b8a 20 */
maclobdell 0:f7c60d3e7b8a 21
maclobdell 0:f7c60d3e7b8a 22 /*
maclobdell 0:f7c60d3e7b8a 23 * The NIST SP 800-90A DRBGs are described in the following publication.
maclobdell 0:f7c60d3e7b8a 24 * http://csrc.nist.gov/publications/nistpubs/800-90A/SP800-90A.pdf
maclobdell 0:f7c60d3e7b8a 25 * References below are based on rev. 1 (January 2012).
maclobdell 0:f7c60d3e7b8a 26 */
maclobdell 0:f7c60d3e7b8a 27
maclobdell 0:f7c60d3e7b8a 28 #if !defined(MBEDTLS_CONFIG_FILE)
maclobdell 0:f7c60d3e7b8a 29 #include "mbedtls/config.h"
maclobdell 0:f7c60d3e7b8a 30 #else
maclobdell 0:f7c60d3e7b8a 31 #include MBEDTLS_CONFIG_FILE
maclobdell 0:f7c60d3e7b8a 32 #endif
maclobdell 0:f7c60d3e7b8a 33
maclobdell 0:f7c60d3e7b8a 34 #if defined(MBEDTLS_HMAC_DRBG_C)
maclobdell 0:f7c60d3e7b8a 35
maclobdell 0:f7c60d3e7b8a 36 #include "mbedtls/hmac_drbg.h"
maclobdell 0:f7c60d3e7b8a 37
maclobdell 0:f7c60d3e7b8a 38 #include <string.h>
maclobdell 0:f7c60d3e7b8a 39
maclobdell 0:f7c60d3e7b8a 40 #if defined(MBEDTLS_FS_IO)
maclobdell 0:f7c60d3e7b8a 41 #include <stdio.h>
maclobdell 0:f7c60d3e7b8a 42 #endif
maclobdell 0:f7c60d3e7b8a 43
maclobdell 0:f7c60d3e7b8a 44 #if defined(MBEDTLS_SELF_TEST)
maclobdell 0:f7c60d3e7b8a 45 #if defined(MBEDTLS_PLATFORM_C)
maclobdell 0:f7c60d3e7b8a 46 #include "mbedtls/platform.h"
maclobdell 0:f7c60d3e7b8a 47 #else
maclobdell 0:f7c60d3e7b8a 48 #include <stdio.h>
maclobdell 0:f7c60d3e7b8a 49 #define mbedtls_printf printf
maclobdell 0:f7c60d3e7b8a 50 #endif /* MBEDTLS_SELF_TEST */
maclobdell 0:f7c60d3e7b8a 51 #endif /* MBEDTLS_PLATFORM_C */
maclobdell 0:f7c60d3e7b8a 52
maclobdell 0:f7c60d3e7b8a 53 /* Implementation that should never be optimized out by the compiler */
maclobdell 0:f7c60d3e7b8a 54 static void mbedtls_zeroize( void *v, size_t n ) {
maclobdell 0:f7c60d3e7b8a 55 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
maclobdell 0:f7c60d3e7b8a 56 }
maclobdell 0:f7c60d3e7b8a 57
maclobdell 0:f7c60d3e7b8a 58 /*
maclobdell 0:f7c60d3e7b8a 59 * HMAC_DRBG context initialization
maclobdell 0:f7c60d3e7b8a 60 */
maclobdell 0:f7c60d3e7b8a 61 void mbedtls_hmac_drbg_init( mbedtls_hmac_drbg_context *ctx )
maclobdell 0:f7c60d3e7b8a 62 {
maclobdell 0:f7c60d3e7b8a 63 memset( ctx, 0, sizeof( mbedtls_hmac_drbg_context ) );
maclobdell 0:f7c60d3e7b8a 64
maclobdell 0:f7c60d3e7b8a 65 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 66 mbedtls_mutex_init( &ctx->mutex );
maclobdell 0:f7c60d3e7b8a 67 #endif
maclobdell 0:f7c60d3e7b8a 68 }
maclobdell 0:f7c60d3e7b8a 69
maclobdell 0:f7c60d3e7b8a 70 /*
maclobdell 0:f7c60d3e7b8a 71 * HMAC_DRBG update, using optional additional data (10.1.2.2)
maclobdell 0:f7c60d3e7b8a 72 */
maclobdell 0:f7c60d3e7b8a 73 void mbedtls_hmac_drbg_update( mbedtls_hmac_drbg_context *ctx,
maclobdell 0:f7c60d3e7b8a 74 const unsigned char *additional, size_t add_len )
maclobdell 0:f7c60d3e7b8a 75 {
maclobdell 0:f7c60d3e7b8a 76 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
maclobdell 0:f7c60d3e7b8a 77 unsigned char rounds = ( additional != NULL && add_len != 0 ) ? 2 : 1;
maclobdell 0:f7c60d3e7b8a 78 unsigned char sep[1];
maclobdell 0:f7c60d3e7b8a 79 unsigned char K[MBEDTLS_MD_MAX_SIZE];
maclobdell 0:f7c60d3e7b8a 80
maclobdell 0:f7c60d3e7b8a 81 for( sep[0] = 0; sep[0] < rounds; sep[0]++ )
maclobdell 0:f7c60d3e7b8a 82 {
maclobdell 0:f7c60d3e7b8a 83 /* Step 1 or 4 */
maclobdell 0:f7c60d3e7b8a 84 mbedtls_md_hmac_reset( &ctx->md_ctx );
maclobdell 0:f7c60d3e7b8a 85 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
maclobdell 0:f7c60d3e7b8a 86 mbedtls_md_hmac_update( &ctx->md_ctx, sep, 1 );
maclobdell 0:f7c60d3e7b8a 87 if( rounds == 2 )
maclobdell 0:f7c60d3e7b8a 88 mbedtls_md_hmac_update( &ctx->md_ctx, additional, add_len );
maclobdell 0:f7c60d3e7b8a 89 mbedtls_md_hmac_finish( &ctx->md_ctx, K );
maclobdell 0:f7c60d3e7b8a 90
maclobdell 0:f7c60d3e7b8a 91 /* Step 2 or 5 */
maclobdell 0:f7c60d3e7b8a 92 mbedtls_md_hmac_starts( &ctx->md_ctx, K, md_len );
maclobdell 0:f7c60d3e7b8a 93 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
maclobdell 0:f7c60d3e7b8a 94 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
maclobdell 0:f7c60d3e7b8a 95 }
maclobdell 0:f7c60d3e7b8a 96 }
maclobdell 0:f7c60d3e7b8a 97
maclobdell 0:f7c60d3e7b8a 98 /*
maclobdell 0:f7c60d3e7b8a 99 * Simplified HMAC_DRBG initialisation (for use with deterministic ECDSA)
maclobdell 0:f7c60d3e7b8a 100 */
maclobdell 0:f7c60d3e7b8a 101 int mbedtls_hmac_drbg_seed_buf( mbedtls_hmac_drbg_context *ctx,
maclobdell 0:f7c60d3e7b8a 102 const mbedtls_md_info_t * md_info,
maclobdell 0:f7c60d3e7b8a 103 const unsigned char *data, size_t data_len )
maclobdell 0:f7c60d3e7b8a 104 {
maclobdell 0:f7c60d3e7b8a 105 int ret;
maclobdell 0:f7c60d3e7b8a 106
maclobdell 0:f7c60d3e7b8a 107 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 108 return( ret );
maclobdell 0:f7c60d3e7b8a 109
maclobdell 0:f7c60d3e7b8a 110 /*
maclobdell 0:f7c60d3e7b8a 111 * Set initial working state.
maclobdell 0:f7c60d3e7b8a 112 * Use the V memory location, which is currently all 0, to initialize the
maclobdell 0:f7c60d3e7b8a 113 * MD context with an all-zero key. Then set V to its initial value.
maclobdell 0:f7c60d3e7b8a 114 */
maclobdell 0:f7c60d3e7b8a 115 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, mbedtls_md_get_size( md_info ) );
maclobdell 0:f7c60d3e7b8a 116 memset( ctx->V, 0x01, mbedtls_md_get_size( md_info ) );
maclobdell 0:f7c60d3e7b8a 117
maclobdell 0:f7c60d3e7b8a 118 mbedtls_hmac_drbg_update( ctx, data, data_len );
maclobdell 0:f7c60d3e7b8a 119
maclobdell 0:f7c60d3e7b8a 120 return( 0 );
maclobdell 0:f7c60d3e7b8a 121 }
maclobdell 0:f7c60d3e7b8a 122
maclobdell 0:f7c60d3e7b8a 123 /*
maclobdell 0:f7c60d3e7b8a 124 * HMAC_DRBG reseeding: 10.1.2.4 (arabic) + 9.2 (Roman)
maclobdell 0:f7c60d3e7b8a 125 */
maclobdell 0:f7c60d3e7b8a 126 int mbedtls_hmac_drbg_reseed( mbedtls_hmac_drbg_context *ctx,
maclobdell 0:f7c60d3e7b8a 127 const unsigned char *additional, size_t len )
maclobdell 0:f7c60d3e7b8a 128 {
maclobdell 0:f7c60d3e7b8a 129 unsigned char seed[MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT];
maclobdell 0:f7c60d3e7b8a 130 size_t seedlen;
maclobdell 0:f7c60d3e7b8a 131
maclobdell 0:f7c60d3e7b8a 132 /* III. Check input length */
maclobdell 0:f7c60d3e7b8a 133 if( len > MBEDTLS_HMAC_DRBG_MAX_INPUT ||
maclobdell 0:f7c60d3e7b8a 134 ctx->entropy_len + len > MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT )
maclobdell 0:f7c60d3e7b8a 135 {
maclobdell 0:f7c60d3e7b8a 136 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
maclobdell 0:f7c60d3e7b8a 137 }
maclobdell 0:f7c60d3e7b8a 138
maclobdell 0:f7c60d3e7b8a 139 memset( seed, 0, MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT );
maclobdell 0:f7c60d3e7b8a 140
maclobdell 0:f7c60d3e7b8a 141 /* IV. Gather entropy_len bytes of entropy for the seed */
maclobdell 0:f7c60d3e7b8a 142 if( ctx->f_entropy( ctx->p_entropy, seed, ctx->entropy_len ) != 0 )
maclobdell 0:f7c60d3e7b8a 143 return( MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED );
maclobdell 0:f7c60d3e7b8a 144
maclobdell 0:f7c60d3e7b8a 145 seedlen = ctx->entropy_len;
maclobdell 0:f7c60d3e7b8a 146
maclobdell 0:f7c60d3e7b8a 147 /* 1. Concatenate entropy and additional data if any */
maclobdell 0:f7c60d3e7b8a 148 if( additional != NULL && len != 0 )
maclobdell 0:f7c60d3e7b8a 149 {
maclobdell 0:f7c60d3e7b8a 150 memcpy( seed + seedlen, additional, len );
maclobdell 0:f7c60d3e7b8a 151 seedlen += len;
maclobdell 0:f7c60d3e7b8a 152 }
maclobdell 0:f7c60d3e7b8a 153
maclobdell 0:f7c60d3e7b8a 154 /* 2. Update state */
maclobdell 0:f7c60d3e7b8a 155 mbedtls_hmac_drbg_update( ctx, seed, seedlen );
maclobdell 0:f7c60d3e7b8a 156
maclobdell 0:f7c60d3e7b8a 157 /* 3. Reset reseed_counter */
maclobdell 0:f7c60d3e7b8a 158 ctx->reseed_counter = 1;
maclobdell 0:f7c60d3e7b8a 159
maclobdell 0:f7c60d3e7b8a 160 /* 4. Done */
maclobdell 0:f7c60d3e7b8a 161 return( 0 );
maclobdell 0:f7c60d3e7b8a 162 }
maclobdell 0:f7c60d3e7b8a 163
maclobdell 0:f7c60d3e7b8a 164 /*
maclobdell 0:f7c60d3e7b8a 165 * HMAC_DRBG initialisation (10.1.2.3 + 9.1)
maclobdell 0:f7c60d3e7b8a 166 */
maclobdell 0:f7c60d3e7b8a 167 int mbedtls_hmac_drbg_seed( mbedtls_hmac_drbg_context *ctx,
maclobdell 0:f7c60d3e7b8a 168 const mbedtls_md_info_t * md_info,
maclobdell 0:f7c60d3e7b8a 169 int (*f_entropy)(void *, unsigned char *, size_t),
maclobdell 0:f7c60d3e7b8a 170 void *p_entropy,
maclobdell 0:f7c60d3e7b8a 171 const unsigned char *custom,
maclobdell 0:f7c60d3e7b8a 172 size_t len )
maclobdell 0:f7c60d3e7b8a 173 {
maclobdell 0:f7c60d3e7b8a 174 int ret;
maclobdell 0:f7c60d3e7b8a 175 size_t entropy_len, md_size;
maclobdell 0:f7c60d3e7b8a 176
maclobdell 0:f7c60d3e7b8a 177 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 178 return( ret );
maclobdell 0:f7c60d3e7b8a 179
maclobdell 0:f7c60d3e7b8a 180 md_size = mbedtls_md_get_size( md_info );
maclobdell 0:f7c60d3e7b8a 181
maclobdell 0:f7c60d3e7b8a 182 /*
maclobdell 0:f7c60d3e7b8a 183 * Set initial working state.
maclobdell 0:f7c60d3e7b8a 184 * Use the V memory location, which is currently all 0, to initialize the
maclobdell 0:f7c60d3e7b8a 185 * MD context with an all-zero key. Then set V to its initial value.
maclobdell 0:f7c60d3e7b8a 186 */
maclobdell 0:f7c60d3e7b8a 187 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, md_size );
maclobdell 0:f7c60d3e7b8a 188 memset( ctx->V, 0x01, md_size );
maclobdell 0:f7c60d3e7b8a 189
maclobdell 0:f7c60d3e7b8a 190 ctx->f_entropy = f_entropy;
maclobdell 0:f7c60d3e7b8a 191 ctx->p_entropy = p_entropy;
maclobdell 0:f7c60d3e7b8a 192
maclobdell 0:f7c60d3e7b8a 193 ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL;
maclobdell 0:f7c60d3e7b8a 194
maclobdell 0:f7c60d3e7b8a 195 /*
maclobdell 0:f7c60d3e7b8a 196 * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by
maclobdell 0:f7c60d3e7b8a 197 * each hash function, then according to SP800-90A rev1 10.1 table 2,
maclobdell 0:f7c60d3e7b8a 198 * min_entropy_len (in bits) is security_strength.
maclobdell 0:f7c60d3e7b8a 199 *
maclobdell 0:f7c60d3e7b8a 200 * (This also matches the sizes used in the NIST test vectors.)
maclobdell 0:f7c60d3e7b8a 201 */
maclobdell 0:f7c60d3e7b8a 202 entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */
maclobdell 0:f7c60d3e7b8a 203 md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */
maclobdell 0:f7c60d3e7b8a 204 32; /* better (256+) -> 256 bits */
maclobdell 0:f7c60d3e7b8a 205
maclobdell 0:f7c60d3e7b8a 206 /*
maclobdell 0:f7c60d3e7b8a 207 * For initialisation, use more entropy to emulate a nonce
maclobdell 0:f7c60d3e7b8a 208 * (Again, matches test vectors.)
maclobdell 0:f7c60d3e7b8a 209 */
maclobdell 0:f7c60d3e7b8a 210 ctx->entropy_len = entropy_len * 3 / 2;
maclobdell 0:f7c60d3e7b8a 211
maclobdell 0:f7c60d3e7b8a 212 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, custom, len ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 213 return( ret );
maclobdell 0:f7c60d3e7b8a 214
maclobdell 0:f7c60d3e7b8a 215 ctx->entropy_len = entropy_len;
maclobdell 0:f7c60d3e7b8a 216
maclobdell 0:f7c60d3e7b8a 217 return( 0 );
maclobdell 0:f7c60d3e7b8a 218 }
maclobdell 0:f7c60d3e7b8a 219
maclobdell 0:f7c60d3e7b8a 220 /*
maclobdell 0:f7c60d3e7b8a 221 * Set prediction resistance
maclobdell 0:f7c60d3e7b8a 222 */
maclobdell 0:f7c60d3e7b8a 223 void mbedtls_hmac_drbg_set_prediction_resistance( mbedtls_hmac_drbg_context *ctx,
maclobdell 0:f7c60d3e7b8a 224 int resistance )
maclobdell 0:f7c60d3e7b8a 225 {
maclobdell 0:f7c60d3e7b8a 226 ctx->prediction_resistance = resistance;
maclobdell 0:f7c60d3e7b8a 227 }
maclobdell 0:f7c60d3e7b8a 228
maclobdell 0:f7c60d3e7b8a 229 /*
maclobdell 0:f7c60d3e7b8a 230 * Set entropy length grabbed for reseeds
maclobdell 0:f7c60d3e7b8a 231 */
maclobdell 0:f7c60d3e7b8a 232 void mbedtls_hmac_drbg_set_entropy_len( mbedtls_hmac_drbg_context *ctx, size_t len )
maclobdell 0:f7c60d3e7b8a 233 {
maclobdell 0:f7c60d3e7b8a 234 ctx->entropy_len = len;
maclobdell 0:f7c60d3e7b8a 235 }
maclobdell 0:f7c60d3e7b8a 236
maclobdell 0:f7c60d3e7b8a 237 /*
maclobdell 0:f7c60d3e7b8a 238 * Set reseed interval
maclobdell 0:f7c60d3e7b8a 239 */
maclobdell 0:f7c60d3e7b8a 240 void mbedtls_hmac_drbg_set_reseed_interval( mbedtls_hmac_drbg_context *ctx, int interval )
maclobdell 0:f7c60d3e7b8a 241 {
maclobdell 0:f7c60d3e7b8a 242 ctx->reseed_interval = interval;
maclobdell 0:f7c60d3e7b8a 243 }
maclobdell 0:f7c60d3e7b8a 244
maclobdell 0:f7c60d3e7b8a 245 /*
maclobdell 0:f7c60d3e7b8a 246 * HMAC_DRBG random function with optional additional data:
maclobdell 0:f7c60d3e7b8a 247 * 10.1.2.5 (arabic) + 9.3 (Roman)
maclobdell 0:f7c60d3e7b8a 248 */
maclobdell 0:f7c60d3e7b8a 249 int mbedtls_hmac_drbg_random_with_add( void *p_rng,
maclobdell 0:f7c60d3e7b8a 250 unsigned char *output, size_t out_len,
maclobdell 0:f7c60d3e7b8a 251 const unsigned char *additional, size_t add_len )
maclobdell 0:f7c60d3e7b8a 252 {
maclobdell 0:f7c60d3e7b8a 253 int ret;
maclobdell 0:f7c60d3e7b8a 254 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
maclobdell 0:f7c60d3e7b8a 255 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
maclobdell 0:f7c60d3e7b8a 256 size_t left = out_len;
maclobdell 0:f7c60d3e7b8a 257 unsigned char *out = output;
maclobdell 0:f7c60d3e7b8a 258
maclobdell 0:f7c60d3e7b8a 259 /* II. Check request length */
maclobdell 0:f7c60d3e7b8a 260 if( out_len > MBEDTLS_HMAC_DRBG_MAX_REQUEST )
maclobdell 0:f7c60d3e7b8a 261 return( MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG );
maclobdell 0:f7c60d3e7b8a 262
maclobdell 0:f7c60d3e7b8a 263 /* III. Check input length */
maclobdell 0:f7c60d3e7b8a 264 if( add_len > MBEDTLS_HMAC_DRBG_MAX_INPUT )
maclobdell 0:f7c60d3e7b8a 265 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
maclobdell 0:f7c60d3e7b8a 266
maclobdell 0:f7c60d3e7b8a 267 /* 1. (aka VII and IX) Check reseed counter and PR */
maclobdell 0:f7c60d3e7b8a 268 if( ctx->f_entropy != NULL && /* For no-reseeding instances */
maclobdell 0:f7c60d3e7b8a 269 ( ctx->prediction_resistance == MBEDTLS_HMAC_DRBG_PR_ON ||
maclobdell 0:f7c60d3e7b8a 270 ctx->reseed_counter > ctx->reseed_interval ) )
maclobdell 0:f7c60d3e7b8a 271 {
maclobdell 0:f7c60d3e7b8a 272 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, additional, add_len ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 273 return( ret );
maclobdell 0:f7c60d3e7b8a 274
maclobdell 0:f7c60d3e7b8a 275 add_len = 0; /* VII.4 */
maclobdell 0:f7c60d3e7b8a 276 }
maclobdell 0:f7c60d3e7b8a 277
maclobdell 0:f7c60d3e7b8a 278 /* 2. Use additional data if any */
maclobdell 0:f7c60d3e7b8a 279 if( additional != NULL && add_len != 0 )
maclobdell 0:f7c60d3e7b8a 280 mbedtls_hmac_drbg_update( ctx, additional, add_len );
maclobdell 0:f7c60d3e7b8a 281
maclobdell 0:f7c60d3e7b8a 282 /* 3, 4, 5. Generate bytes */
maclobdell 0:f7c60d3e7b8a 283 while( left != 0 )
maclobdell 0:f7c60d3e7b8a 284 {
maclobdell 0:f7c60d3e7b8a 285 size_t use_len = left > md_len ? md_len : left;
maclobdell 0:f7c60d3e7b8a 286
maclobdell 0:f7c60d3e7b8a 287 mbedtls_md_hmac_reset( &ctx->md_ctx );
maclobdell 0:f7c60d3e7b8a 288 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
maclobdell 0:f7c60d3e7b8a 289 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
maclobdell 0:f7c60d3e7b8a 290
maclobdell 0:f7c60d3e7b8a 291 memcpy( out, ctx->V, use_len );
maclobdell 0:f7c60d3e7b8a 292 out += use_len;
maclobdell 0:f7c60d3e7b8a 293 left -= use_len;
maclobdell 0:f7c60d3e7b8a 294 }
maclobdell 0:f7c60d3e7b8a 295
maclobdell 0:f7c60d3e7b8a 296 /* 6. Update */
maclobdell 0:f7c60d3e7b8a 297 mbedtls_hmac_drbg_update( ctx, additional, add_len );
maclobdell 0:f7c60d3e7b8a 298
maclobdell 0:f7c60d3e7b8a 299 /* 7. Update reseed counter */
maclobdell 0:f7c60d3e7b8a 300 ctx->reseed_counter++;
maclobdell 0:f7c60d3e7b8a 301
maclobdell 0:f7c60d3e7b8a 302 /* 8. Done */
maclobdell 0:f7c60d3e7b8a 303 return( 0 );
maclobdell 0:f7c60d3e7b8a 304 }
maclobdell 0:f7c60d3e7b8a 305
maclobdell 0:f7c60d3e7b8a 306 /*
maclobdell 0:f7c60d3e7b8a 307 * HMAC_DRBG random function
maclobdell 0:f7c60d3e7b8a 308 */
maclobdell 0:f7c60d3e7b8a 309 int mbedtls_hmac_drbg_random( void *p_rng, unsigned char *output, size_t out_len )
maclobdell 0:f7c60d3e7b8a 310 {
maclobdell 0:f7c60d3e7b8a 311 int ret;
maclobdell 0:f7c60d3e7b8a 312 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
maclobdell 0:f7c60d3e7b8a 313
maclobdell 0:f7c60d3e7b8a 314 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 315 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 316 return( ret );
maclobdell 0:f7c60d3e7b8a 317 #endif
maclobdell 0:f7c60d3e7b8a 318
maclobdell 0:f7c60d3e7b8a 319 ret = mbedtls_hmac_drbg_random_with_add( ctx, output, out_len, NULL, 0 );
maclobdell 0:f7c60d3e7b8a 320
maclobdell 0:f7c60d3e7b8a 321 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 322 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
maclobdell 0:f7c60d3e7b8a 323 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
maclobdell 0:f7c60d3e7b8a 324 #endif
maclobdell 0:f7c60d3e7b8a 325
maclobdell 0:f7c60d3e7b8a 326 return( ret );
maclobdell 0:f7c60d3e7b8a 327 }
maclobdell 0:f7c60d3e7b8a 328
maclobdell 0:f7c60d3e7b8a 329 /*
maclobdell 0:f7c60d3e7b8a 330 * Free an HMAC_DRBG context
maclobdell 0:f7c60d3e7b8a 331 */
maclobdell 0:f7c60d3e7b8a 332 void mbedtls_hmac_drbg_free( mbedtls_hmac_drbg_context *ctx )
maclobdell 0:f7c60d3e7b8a 333 {
maclobdell 0:f7c60d3e7b8a 334 if( ctx == NULL )
maclobdell 0:f7c60d3e7b8a 335 return;
maclobdell 0:f7c60d3e7b8a 336
maclobdell 0:f7c60d3e7b8a 337 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 338 mbedtls_mutex_free( &ctx->mutex );
maclobdell 0:f7c60d3e7b8a 339 #endif
maclobdell 0:f7c60d3e7b8a 340 mbedtls_md_free( &ctx->md_ctx );
maclobdell 0:f7c60d3e7b8a 341 mbedtls_zeroize( ctx, sizeof( mbedtls_hmac_drbg_context ) );
maclobdell 0:f7c60d3e7b8a 342 }
maclobdell 0:f7c60d3e7b8a 343
maclobdell 0:f7c60d3e7b8a 344 #if defined(MBEDTLS_FS_IO)
maclobdell 0:f7c60d3e7b8a 345 int mbedtls_hmac_drbg_write_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
maclobdell 0:f7c60d3e7b8a 346 {
maclobdell 0:f7c60d3e7b8a 347 int ret;
maclobdell 0:f7c60d3e7b8a 348 FILE *f;
maclobdell 0:f7c60d3e7b8a 349 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
maclobdell 0:f7c60d3e7b8a 350
maclobdell 0:f7c60d3e7b8a 351 if( ( f = fopen( path, "wb" ) ) == NULL )
maclobdell 0:f7c60d3e7b8a 352 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
maclobdell 0:f7c60d3e7b8a 353
maclobdell 0:f7c60d3e7b8a 354 if( ( ret = mbedtls_hmac_drbg_random( ctx, buf, sizeof( buf ) ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 355 goto exit;
maclobdell 0:f7c60d3e7b8a 356
maclobdell 0:f7c60d3e7b8a 357 if( fwrite( buf, 1, sizeof( buf ), f ) != sizeof( buf ) )
maclobdell 0:f7c60d3e7b8a 358 {
maclobdell 0:f7c60d3e7b8a 359 ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
maclobdell 0:f7c60d3e7b8a 360 goto exit;
maclobdell 0:f7c60d3e7b8a 361 }
maclobdell 0:f7c60d3e7b8a 362
maclobdell 0:f7c60d3e7b8a 363 ret = 0;
maclobdell 0:f7c60d3e7b8a 364
maclobdell 0:f7c60d3e7b8a 365 exit:
maclobdell 0:f7c60d3e7b8a 366 fclose( f );
maclobdell 0:f7c60d3e7b8a 367 return( ret );
maclobdell 0:f7c60d3e7b8a 368 }
maclobdell 0:f7c60d3e7b8a 369
maclobdell 0:f7c60d3e7b8a 370 int mbedtls_hmac_drbg_update_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
maclobdell 0:f7c60d3e7b8a 371 {
maclobdell 0:f7c60d3e7b8a 372 FILE *f;
maclobdell 0:f7c60d3e7b8a 373 size_t n;
maclobdell 0:f7c60d3e7b8a 374 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
maclobdell 0:f7c60d3e7b8a 375
maclobdell 0:f7c60d3e7b8a 376 if( ( f = fopen( path, "rb" ) ) == NULL )
maclobdell 0:f7c60d3e7b8a 377 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
maclobdell 0:f7c60d3e7b8a 378
maclobdell 0:f7c60d3e7b8a 379 fseek( f, 0, SEEK_END );
maclobdell 0:f7c60d3e7b8a 380 n = (size_t) ftell( f );
maclobdell 0:f7c60d3e7b8a 381 fseek( f, 0, SEEK_SET );
maclobdell 0:f7c60d3e7b8a 382
maclobdell 0:f7c60d3e7b8a 383 if( n > MBEDTLS_HMAC_DRBG_MAX_INPUT )
maclobdell 0:f7c60d3e7b8a 384 {
maclobdell 0:f7c60d3e7b8a 385 fclose( f );
maclobdell 0:f7c60d3e7b8a 386 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
maclobdell 0:f7c60d3e7b8a 387 }
maclobdell 0:f7c60d3e7b8a 388
maclobdell 0:f7c60d3e7b8a 389 if( fread( buf, 1, n, f ) != n )
maclobdell 0:f7c60d3e7b8a 390 {
maclobdell 0:f7c60d3e7b8a 391 fclose( f );
maclobdell 0:f7c60d3e7b8a 392 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
maclobdell 0:f7c60d3e7b8a 393 }
maclobdell 0:f7c60d3e7b8a 394
maclobdell 0:f7c60d3e7b8a 395 fclose( f );
maclobdell 0:f7c60d3e7b8a 396
maclobdell 0:f7c60d3e7b8a 397 mbedtls_hmac_drbg_update( ctx, buf, n );
maclobdell 0:f7c60d3e7b8a 398
maclobdell 0:f7c60d3e7b8a 399 return( mbedtls_hmac_drbg_write_seed_file( ctx, path ) );
maclobdell 0:f7c60d3e7b8a 400 }
maclobdell 0:f7c60d3e7b8a 401 #endif /* MBEDTLS_FS_IO */
maclobdell 0:f7c60d3e7b8a 402
maclobdell 0:f7c60d3e7b8a 403
maclobdell 0:f7c60d3e7b8a 404 #if defined(MBEDTLS_SELF_TEST)
maclobdell 0:f7c60d3e7b8a 405
maclobdell 0:f7c60d3e7b8a 406 #if !defined(MBEDTLS_SHA1_C)
maclobdell 0:f7c60d3e7b8a 407 /* Dummy checkup routine */
maclobdell 0:f7c60d3e7b8a 408 int mbedtls_hmac_drbg_self_test( int verbose )
maclobdell 0:f7c60d3e7b8a 409 {
maclobdell 0:f7c60d3e7b8a 410 (void) verbose;
maclobdell 0:f7c60d3e7b8a 411 return( 0 );
maclobdell 0:f7c60d3e7b8a 412 }
maclobdell 0:f7c60d3e7b8a 413 #else
maclobdell 0:f7c60d3e7b8a 414
maclobdell 0:f7c60d3e7b8a 415 #define OUTPUT_LEN 80
maclobdell 0:f7c60d3e7b8a 416
maclobdell 0:f7c60d3e7b8a 417 /* From a NIST PR=true test vector */
maclobdell 0:f7c60d3e7b8a 418 static const unsigned char entropy_pr[] = {
maclobdell 0:f7c60d3e7b8a 419 0xa0, 0xc9, 0xab, 0x58, 0xf1, 0xe2, 0xe5, 0xa4, 0xde, 0x3e, 0xbd, 0x4f,
maclobdell 0:f7c60d3e7b8a 420 0xf7, 0x3e, 0x9c, 0x5b, 0x64, 0xef, 0xd8, 0xca, 0x02, 0x8c, 0xf8, 0x11,
maclobdell 0:f7c60d3e7b8a 421 0x48, 0xa5, 0x84, 0xfe, 0x69, 0xab, 0x5a, 0xee, 0x42, 0xaa, 0x4d, 0x42,
maclobdell 0:f7c60d3e7b8a 422 0x17, 0x60, 0x99, 0xd4, 0x5e, 0x13, 0x97, 0xdc, 0x40, 0x4d, 0x86, 0xa3,
maclobdell 0:f7c60d3e7b8a 423 0x7b, 0xf5, 0x59, 0x54, 0x75, 0x69, 0x51, 0xe4 };
maclobdell 0:f7c60d3e7b8a 424 static const unsigned char result_pr[OUTPUT_LEN] = {
maclobdell 0:f7c60d3e7b8a 425 0x9a, 0x00, 0xa2, 0xd0, 0x0e, 0xd5, 0x9b, 0xfe, 0x31, 0xec, 0xb1, 0x39,
maclobdell 0:f7c60d3e7b8a 426 0x9b, 0x60, 0x81, 0x48, 0xd1, 0x96, 0x9d, 0x25, 0x0d, 0x3c, 0x1e, 0x94,
maclobdell 0:f7c60d3e7b8a 427 0x10, 0x10, 0x98, 0x12, 0x93, 0x25, 0xca, 0xb8, 0xfc, 0xcc, 0x2d, 0x54,
maclobdell 0:f7c60d3e7b8a 428 0x73, 0x19, 0x70, 0xc0, 0x10, 0x7a, 0xa4, 0x89, 0x25, 0x19, 0x95, 0x5e,
maclobdell 0:f7c60d3e7b8a 429 0x4b, 0xc6, 0x00, 0x1d, 0x7f, 0x4e, 0x6a, 0x2b, 0xf8, 0xa3, 0x01, 0xab,
maclobdell 0:f7c60d3e7b8a 430 0x46, 0x05, 0x5c, 0x09, 0xa6, 0x71, 0x88, 0xf1, 0xa7, 0x40, 0xee, 0xf3,
maclobdell 0:f7c60d3e7b8a 431 0xe1, 0x5c, 0x02, 0x9b, 0x44, 0xaf, 0x03, 0x44 };
maclobdell 0:f7c60d3e7b8a 432
maclobdell 0:f7c60d3e7b8a 433 /* From a NIST PR=false test vector */
maclobdell 0:f7c60d3e7b8a 434 static const unsigned char entropy_nopr[] = {
maclobdell 0:f7c60d3e7b8a 435 0x79, 0x34, 0x9b, 0xbf, 0x7c, 0xdd, 0xa5, 0x79, 0x95, 0x57, 0x86, 0x66,
maclobdell 0:f7c60d3e7b8a 436 0x21, 0xc9, 0x13, 0x83, 0x11, 0x46, 0x73, 0x3a, 0xbf, 0x8c, 0x35, 0xc8,
maclobdell 0:f7c60d3e7b8a 437 0xc7, 0x21, 0x5b, 0x5b, 0x96, 0xc4, 0x8e, 0x9b, 0x33, 0x8c, 0x74, 0xe3,
maclobdell 0:f7c60d3e7b8a 438 0xe9, 0x9d, 0xfe, 0xdf };
maclobdell 0:f7c60d3e7b8a 439 static const unsigned char result_nopr[OUTPUT_LEN] = {
maclobdell 0:f7c60d3e7b8a 440 0xc6, 0xa1, 0x6a, 0xb8, 0xd4, 0x20, 0x70, 0x6f, 0x0f, 0x34, 0xab, 0x7f,
maclobdell 0:f7c60d3e7b8a 441 0xec, 0x5a, 0xdc, 0xa9, 0xd8, 0xca, 0x3a, 0x13, 0x3e, 0x15, 0x9c, 0xa6,
maclobdell 0:f7c60d3e7b8a 442 0xac, 0x43, 0xc6, 0xf8, 0xa2, 0xbe, 0x22, 0x83, 0x4a, 0x4c, 0x0a, 0x0a,
maclobdell 0:f7c60d3e7b8a 443 0xff, 0xb1, 0x0d, 0x71, 0x94, 0xf1, 0xc1, 0xa5, 0xcf, 0x73, 0x22, 0xec,
maclobdell 0:f7c60d3e7b8a 444 0x1a, 0xe0, 0x96, 0x4e, 0xd4, 0xbf, 0x12, 0x27, 0x46, 0xe0, 0x87, 0xfd,
maclobdell 0:f7c60d3e7b8a 445 0xb5, 0xb3, 0xe9, 0x1b, 0x34, 0x93, 0xd5, 0xbb, 0x98, 0xfa, 0xed, 0x49,
maclobdell 0:f7c60d3e7b8a 446 0xe8, 0x5f, 0x13, 0x0f, 0xc8, 0xa4, 0x59, 0xb7 };
maclobdell 0:f7c60d3e7b8a 447
maclobdell 0:f7c60d3e7b8a 448 /* "Entropy" from buffer */
maclobdell 0:f7c60d3e7b8a 449 static size_t test_offset;
maclobdell 0:f7c60d3e7b8a 450 static int hmac_drbg_self_test_entropy( void *data,
maclobdell 0:f7c60d3e7b8a 451 unsigned char *buf, size_t len )
maclobdell 0:f7c60d3e7b8a 452 {
maclobdell 0:f7c60d3e7b8a 453 const unsigned char *p = data;
maclobdell 0:f7c60d3e7b8a 454 memcpy( buf, p + test_offset, len );
maclobdell 0:f7c60d3e7b8a 455 test_offset += len;
maclobdell 0:f7c60d3e7b8a 456 return( 0 );
maclobdell 0:f7c60d3e7b8a 457 }
maclobdell 0:f7c60d3e7b8a 458
maclobdell 0:f7c60d3e7b8a 459 #define CHK( c ) if( (c) != 0 ) \
maclobdell 0:f7c60d3e7b8a 460 { \
maclobdell 0:f7c60d3e7b8a 461 if( verbose != 0 ) \
maclobdell 0:f7c60d3e7b8a 462 mbedtls_printf( "failed\n" ); \
maclobdell 0:f7c60d3e7b8a 463 return( 1 ); \
maclobdell 0:f7c60d3e7b8a 464 }
maclobdell 0:f7c60d3e7b8a 465
maclobdell 0:f7c60d3e7b8a 466 /*
maclobdell 0:f7c60d3e7b8a 467 * Checkup routine for HMAC_DRBG with SHA-1
maclobdell 0:f7c60d3e7b8a 468 */
maclobdell 0:f7c60d3e7b8a 469 int mbedtls_hmac_drbg_self_test( int verbose )
maclobdell 0:f7c60d3e7b8a 470 {
maclobdell 0:f7c60d3e7b8a 471 mbedtls_hmac_drbg_context ctx;
maclobdell 0:f7c60d3e7b8a 472 unsigned char buf[OUTPUT_LEN];
maclobdell 0:f7c60d3e7b8a 473 const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
maclobdell 0:f7c60d3e7b8a 474
maclobdell 0:f7c60d3e7b8a 475 mbedtls_hmac_drbg_init( &ctx );
maclobdell 0:f7c60d3e7b8a 476
maclobdell 0:f7c60d3e7b8a 477 /*
maclobdell 0:f7c60d3e7b8a 478 * PR = True
maclobdell 0:f7c60d3e7b8a 479 */
maclobdell 0:f7c60d3e7b8a 480 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 481 mbedtls_printf( " HMAC_DRBG (PR = True) : " );
maclobdell 0:f7c60d3e7b8a 482
maclobdell 0:f7c60d3e7b8a 483 test_offset = 0;
maclobdell 0:f7c60d3e7b8a 484 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
maclobdell 0:f7c60d3e7b8a 485 hmac_drbg_self_test_entropy, (void *) entropy_pr,
maclobdell 0:f7c60d3e7b8a 486 NULL, 0 ) );
maclobdell 0:f7c60d3e7b8a 487 mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
maclobdell 0:f7c60d3e7b8a 488 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
maclobdell 0:f7c60d3e7b8a 489 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
maclobdell 0:f7c60d3e7b8a 490 CHK( memcmp( buf, result_pr, OUTPUT_LEN ) );
maclobdell 0:f7c60d3e7b8a 491 mbedtls_hmac_drbg_free( &ctx );
maclobdell 0:f7c60d3e7b8a 492
maclobdell 0:f7c60d3e7b8a 493 mbedtls_hmac_drbg_free( &ctx );
maclobdell 0:f7c60d3e7b8a 494
maclobdell 0:f7c60d3e7b8a 495 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 496 mbedtls_printf( "passed\n" );
maclobdell 0:f7c60d3e7b8a 497
maclobdell 0:f7c60d3e7b8a 498 /*
maclobdell 0:f7c60d3e7b8a 499 * PR = False
maclobdell 0:f7c60d3e7b8a 500 */
maclobdell 0:f7c60d3e7b8a 501 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 502 mbedtls_printf( " HMAC_DRBG (PR = False) : " );
maclobdell 0:f7c60d3e7b8a 503
maclobdell 0:f7c60d3e7b8a 504 mbedtls_hmac_drbg_init( &ctx );
maclobdell 0:f7c60d3e7b8a 505
maclobdell 0:f7c60d3e7b8a 506 test_offset = 0;
maclobdell 0:f7c60d3e7b8a 507 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
maclobdell 0:f7c60d3e7b8a 508 hmac_drbg_self_test_entropy, (void *) entropy_nopr,
maclobdell 0:f7c60d3e7b8a 509 NULL, 0 ) );
maclobdell 0:f7c60d3e7b8a 510 CHK( mbedtls_hmac_drbg_reseed( &ctx, NULL, 0 ) );
maclobdell 0:f7c60d3e7b8a 511 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
maclobdell 0:f7c60d3e7b8a 512 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
maclobdell 0:f7c60d3e7b8a 513 CHK( memcmp( buf, result_nopr, OUTPUT_LEN ) );
maclobdell 0:f7c60d3e7b8a 514 mbedtls_hmac_drbg_free( &ctx );
maclobdell 0:f7c60d3e7b8a 515
maclobdell 0:f7c60d3e7b8a 516 mbedtls_hmac_drbg_free( &ctx );
maclobdell 0:f7c60d3e7b8a 517
maclobdell 0:f7c60d3e7b8a 518 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 519 mbedtls_printf( "passed\n" );
maclobdell 0:f7c60d3e7b8a 520
maclobdell 0:f7c60d3e7b8a 521 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 522 mbedtls_printf( "\n" );
maclobdell 0:f7c60d3e7b8a 523
maclobdell 0:f7c60d3e7b8a 524 return( 0 );
maclobdell 0:f7c60d3e7b8a 525 }
maclobdell 0:f7c60d3e7b8a 526 #endif /* MBEDTLS_SHA1_C */
maclobdell 0:f7c60d3e7b8a 527 #endif /* MBEDTLS_SELF_TEST */
maclobdell 0:f7c60d3e7b8a 528
maclobdell 0:f7c60d3e7b8a 529 #endif /* MBEDTLS_HMAC_DRBG_C */