Maxim nexpaq / nexpaq_dev

Preliminary main mbed library for nexpaq development

features/mbedtls/src/hmac_drbg.c@0:6c56fb4bc5f0, 2016-11-04 (annotated)

Committer:
nexpaq
Date:
Fri Nov 04 20:27:58 2016 +0000
Revision:
0:6c56fb4bc5f0
Moving to library for sharing updates

Who changed what in which revision?

UserRevisionLine numberNew contents of line
nexpaq 0:6c56fb4bc5f0 1 /*
nexpaq 0:6c56fb4bc5f0 2 * HMAC_DRBG implementation (NIST SP 800-90)
nexpaq 0:6c56fb4bc5f0 3 *
nexpaq 0:6c56fb4bc5f0 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
nexpaq 0:6c56fb4bc5f0 5 * SPDX-License-Identifier: Apache-2.0
nexpaq 0:6c56fb4bc5f0 6 *
nexpaq 0:6c56fb4bc5f0 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
nexpaq 0:6c56fb4bc5f0 8 * not use this file except in compliance with the License.
nexpaq 0:6c56fb4bc5f0 9 * You may obtain a copy of the License at
nexpaq 0:6c56fb4bc5f0 10 *
nexpaq 0:6c56fb4bc5f0 11 * http://www.apache.org/licenses/LICENSE-2.0
nexpaq 0:6c56fb4bc5f0 12 *
nexpaq 0:6c56fb4bc5f0 13 * Unless required by applicable law or agreed to in writing, software
nexpaq 0:6c56fb4bc5f0 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
nexpaq 0:6c56fb4bc5f0 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
nexpaq 0:6c56fb4bc5f0 16 * See the License for the specific language governing permissions and
nexpaq 0:6c56fb4bc5f0 17 * limitations under the License.
nexpaq 0:6c56fb4bc5f0 18 *
nexpaq 0:6c56fb4bc5f0 19 * This file is part of mbed TLS (https://tls.mbed.org)
nexpaq 0:6c56fb4bc5f0 20 */
nexpaq 0:6c56fb4bc5f0 21
nexpaq 0:6c56fb4bc5f0 22 /*
nexpaq 0:6c56fb4bc5f0 23 * The NIST SP 800-90A DRBGs are described in the following publication.
nexpaq 0:6c56fb4bc5f0 24 * http://csrc.nist.gov/publications/nistpubs/800-90A/SP800-90A.pdf
nexpaq 0:6c56fb4bc5f0 25 * References below are based on rev. 1 (January 2012).
nexpaq 0:6c56fb4bc5f0 26 */
nexpaq 0:6c56fb4bc5f0 27
nexpaq 0:6c56fb4bc5f0 28 #if !defined(MBEDTLS_CONFIG_FILE)
nexpaq 0:6c56fb4bc5f0 29 #include "mbedtls/config.h"
nexpaq 0:6c56fb4bc5f0 30 #else
nexpaq 0:6c56fb4bc5f0 31 #include MBEDTLS_CONFIG_FILE
nexpaq 0:6c56fb4bc5f0 32 #endif
nexpaq 0:6c56fb4bc5f0 33
nexpaq 0:6c56fb4bc5f0 34 #if defined(MBEDTLS_HMAC_DRBG_C)
nexpaq 0:6c56fb4bc5f0 35
nexpaq 0:6c56fb4bc5f0 36 #include "mbedtls/hmac_drbg.h"
nexpaq 0:6c56fb4bc5f0 37
nexpaq 0:6c56fb4bc5f0 38 #include <string.h>
nexpaq 0:6c56fb4bc5f0 39
nexpaq 0:6c56fb4bc5f0 40 #if defined(MBEDTLS_FS_IO)
nexpaq 0:6c56fb4bc5f0 41 #include <stdio.h>
nexpaq 0:6c56fb4bc5f0 42 #endif
nexpaq 0:6c56fb4bc5f0 43
nexpaq 0:6c56fb4bc5f0 44 #if defined(MBEDTLS_SELF_TEST)
nexpaq 0:6c56fb4bc5f0 45 #if defined(MBEDTLS_PLATFORM_C)
nexpaq 0:6c56fb4bc5f0 46 #include "mbedtls/platform.h"
nexpaq 0:6c56fb4bc5f0 47 #else
nexpaq 0:6c56fb4bc5f0 48 #include <stdio.h>
nexpaq 0:6c56fb4bc5f0 49 #define mbedtls_printf printf
nexpaq 0:6c56fb4bc5f0 50 #endif /* MBEDTLS_SELF_TEST */
nexpaq 0:6c56fb4bc5f0 51 #endif /* MBEDTLS_PLATFORM_C */
nexpaq 0:6c56fb4bc5f0 52
nexpaq 0:6c56fb4bc5f0 53 /* Implementation that should never be optimized out by the compiler */
nexpaq 0:6c56fb4bc5f0 54 static void mbedtls_zeroize( void *v, size_t n ) {
nexpaq 0:6c56fb4bc5f0 55 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
nexpaq 0:6c56fb4bc5f0 56 }
nexpaq 0:6c56fb4bc5f0 57
nexpaq 0:6c56fb4bc5f0 58 /*
nexpaq 0:6c56fb4bc5f0 59 * HMAC_DRBG context initialization
nexpaq 0:6c56fb4bc5f0 60 */
nexpaq 0:6c56fb4bc5f0 61 void mbedtls_hmac_drbg_init( mbedtls_hmac_drbg_context *ctx )
nexpaq 0:6c56fb4bc5f0 62 {
nexpaq 0:6c56fb4bc5f0 63 memset( ctx, 0, sizeof( mbedtls_hmac_drbg_context ) );
nexpaq 0:6c56fb4bc5f0 64
nexpaq 0:6c56fb4bc5f0 65 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 66 mbedtls_mutex_init( &ctx->mutex );
nexpaq 0:6c56fb4bc5f0 67 #endif
nexpaq 0:6c56fb4bc5f0 68 }
nexpaq 0:6c56fb4bc5f0 69
nexpaq 0:6c56fb4bc5f0 70 /*
nexpaq 0:6c56fb4bc5f0 71 * HMAC_DRBG update, using optional additional data (10.1.2.2)
nexpaq 0:6c56fb4bc5f0 72 */
nexpaq 0:6c56fb4bc5f0 73 void mbedtls_hmac_drbg_update( mbedtls_hmac_drbg_context *ctx,
nexpaq 0:6c56fb4bc5f0 74 const unsigned char *additional, size_t add_len )
nexpaq 0:6c56fb4bc5f0 75 {
nexpaq 0:6c56fb4bc5f0 76 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
nexpaq 0:6c56fb4bc5f0 77 unsigned char rounds = ( additional != NULL && add_len != 0 ) ? 2 : 1;
nexpaq 0:6c56fb4bc5f0 78 unsigned char sep[1];
nexpaq 0:6c56fb4bc5f0 79 unsigned char K[MBEDTLS_MD_MAX_SIZE];
nexpaq 0:6c56fb4bc5f0 80
nexpaq 0:6c56fb4bc5f0 81 for( sep[0] = 0; sep[0] < rounds; sep[0]++ )
nexpaq 0:6c56fb4bc5f0 82 {
nexpaq 0:6c56fb4bc5f0 83 /* Step 1 or 4 */
nexpaq 0:6c56fb4bc5f0 84 mbedtls_md_hmac_reset( &ctx->md_ctx );
nexpaq 0:6c56fb4bc5f0 85 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
nexpaq 0:6c56fb4bc5f0 86 mbedtls_md_hmac_update( &ctx->md_ctx, sep, 1 );
nexpaq 0:6c56fb4bc5f0 87 if( rounds == 2 )
nexpaq 0:6c56fb4bc5f0 88 mbedtls_md_hmac_update( &ctx->md_ctx, additional, add_len );
nexpaq 0:6c56fb4bc5f0 89 mbedtls_md_hmac_finish( &ctx->md_ctx, K );
nexpaq 0:6c56fb4bc5f0 90
nexpaq 0:6c56fb4bc5f0 91 /* Step 2 or 5 */
nexpaq 0:6c56fb4bc5f0 92 mbedtls_md_hmac_starts( &ctx->md_ctx, K, md_len );
nexpaq 0:6c56fb4bc5f0 93 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
nexpaq 0:6c56fb4bc5f0 94 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
nexpaq 0:6c56fb4bc5f0 95 }
nexpaq 0:6c56fb4bc5f0 96 }
nexpaq 0:6c56fb4bc5f0 97
nexpaq 0:6c56fb4bc5f0 98 /*
nexpaq 0:6c56fb4bc5f0 99 * Simplified HMAC_DRBG initialisation (for use with deterministic ECDSA)
nexpaq 0:6c56fb4bc5f0 100 */
nexpaq 0:6c56fb4bc5f0 101 int mbedtls_hmac_drbg_seed_buf( mbedtls_hmac_drbg_context *ctx,
nexpaq 0:6c56fb4bc5f0 102 const mbedtls_md_info_t * md_info,
nexpaq 0:6c56fb4bc5f0 103 const unsigned char *data, size_t data_len )
nexpaq 0:6c56fb4bc5f0 104 {
nexpaq 0:6c56fb4bc5f0 105 int ret;
nexpaq 0:6c56fb4bc5f0 106
nexpaq 0:6c56fb4bc5f0 107 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 108 return( ret );
nexpaq 0:6c56fb4bc5f0 109
nexpaq 0:6c56fb4bc5f0 110 /*
nexpaq 0:6c56fb4bc5f0 111 * Set initial working state.
nexpaq 0:6c56fb4bc5f0 112 * Use the V memory location, which is currently all 0, to initialize the
nexpaq 0:6c56fb4bc5f0 113 * MD context with an all-zero key. Then set V to its initial value.
nexpaq 0:6c56fb4bc5f0 114 */
nexpaq 0:6c56fb4bc5f0 115 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, mbedtls_md_get_size( md_info ) );
nexpaq 0:6c56fb4bc5f0 116 memset( ctx->V, 0x01, mbedtls_md_get_size( md_info ) );
nexpaq 0:6c56fb4bc5f0 117
nexpaq 0:6c56fb4bc5f0 118 mbedtls_hmac_drbg_update( ctx, data, data_len );
nexpaq 0:6c56fb4bc5f0 119
nexpaq 0:6c56fb4bc5f0 120 return( 0 );
nexpaq 0:6c56fb4bc5f0 121 }
nexpaq 0:6c56fb4bc5f0 122
nexpaq 0:6c56fb4bc5f0 123 /*
nexpaq 0:6c56fb4bc5f0 124 * HMAC_DRBG reseeding: 10.1.2.4 (arabic) + 9.2 (Roman)
nexpaq 0:6c56fb4bc5f0 125 */
nexpaq 0:6c56fb4bc5f0 126 int mbedtls_hmac_drbg_reseed( mbedtls_hmac_drbg_context *ctx,
nexpaq 0:6c56fb4bc5f0 127 const unsigned char *additional, size_t len )
nexpaq 0:6c56fb4bc5f0 128 {
nexpaq 0:6c56fb4bc5f0 129 unsigned char seed[MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT];
nexpaq 0:6c56fb4bc5f0 130 size_t seedlen;
nexpaq 0:6c56fb4bc5f0 131
nexpaq 0:6c56fb4bc5f0 132 /* III. Check input length */
nexpaq 0:6c56fb4bc5f0 133 if( len > MBEDTLS_HMAC_DRBG_MAX_INPUT ||
nexpaq 0:6c56fb4bc5f0 134 ctx->entropy_len + len > MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT )
nexpaq 0:6c56fb4bc5f0 135 {
nexpaq 0:6c56fb4bc5f0 136 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
nexpaq 0:6c56fb4bc5f0 137 }
nexpaq 0:6c56fb4bc5f0 138
nexpaq 0:6c56fb4bc5f0 139 memset( seed, 0, MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT );
nexpaq 0:6c56fb4bc5f0 140
nexpaq 0:6c56fb4bc5f0 141 /* IV. Gather entropy_len bytes of entropy for the seed */
nexpaq 0:6c56fb4bc5f0 142 if( ctx->f_entropy( ctx->p_entropy, seed, ctx->entropy_len ) != 0 )
nexpaq 0:6c56fb4bc5f0 143 return( MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED );
nexpaq 0:6c56fb4bc5f0 144
nexpaq 0:6c56fb4bc5f0 145 seedlen = ctx->entropy_len;
nexpaq 0:6c56fb4bc5f0 146
nexpaq 0:6c56fb4bc5f0 147 /* 1. Concatenate entropy and additional data if any */
nexpaq 0:6c56fb4bc5f0 148 if( additional != NULL && len != 0 )
nexpaq 0:6c56fb4bc5f0 149 {
nexpaq 0:6c56fb4bc5f0 150 memcpy( seed + seedlen, additional, len );
nexpaq 0:6c56fb4bc5f0 151 seedlen += len;
nexpaq 0:6c56fb4bc5f0 152 }
nexpaq 0:6c56fb4bc5f0 153
nexpaq 0:6c56fb4bc5f0 154 /* 2. Update state */
nexpaq 0:6c56fb4bc5f0 155 mbedtls_hmac_drbg_update( ctx, seed, seedlen );
nexpaq 0:6c56fb4bc5f0 156
nexpaq 0:6c56fb4bc5f0 157 /* 3. Reset reseed_counter */
nexpaq 0:6c56fb4bc5f0 158 ctx->reseed_counter = 1;
nexpaq 0:6c56fb4bc5f0 159
nexpaq 0:6c56fb4bc5f0 160 /* 4. Done */
nexpaq 0:6c56fb4bc5f0 161 return( 0 );
nexpaq 0:6c56fb4bc5f0 162 }
nexpaq 0:6c56fb4bc5f0 163
nexpaq 0:6c56fb4bc5f0 164 /*
nexpaq 0:6c56fb4bc5f0 165 * HMAC_DRBG initialisation (10.1.2.3 + 9.1)
nexpaq 0:6c56fb4bc5f0 166 */
nexpaq 0:6c56fb4bc5f0 167 int mbedtls_hmac_drbg_seed( mbedtls_hmac_drbg_context *ctx,
nexpaq 0:6c56fb4bc5f0 168 const mbedtls_md_info_t * md_info,
nexpaq 0:6c56fb4bc5f0 169 int (*f_entropy)(void *, unsigned char *, size_t),
nexpaq 0:6c56fb4bc5f0 170 void *p_entropy,
nexpaq 0:6c56fb4bc5f0 171 const unsigned char *custom,
nexpaq 0:6c56fb4bc5f0 172 size_t len )
nexpaq 0:6c56fb4bc5f0 173 {
nexpaq 0:6c56fb4bc5f0 174 int ret;
nexpaq 0:6c56fb4bc5f0 175 size_t entropy_len, md_size;
nexpaq 0:6c56fb4bc5f0 176
nexpaq 0:6c56fb4bc5f0 177 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 178 return( ret );
nexpaq 0:6c56fb4bc5f0 179
nexpaq 0:6c56fb4bc5f0 180 md_size = mbedtls_md_get_size( md_info );
nexpaq 0:6c56fb4bc5f0 181
nexpaq 0:6c56fb4bc5f0 182 /*
nexpaq 0:6c56fb4bc5f0 183 * Set initial working state.
nexpaq 0:6c56fb4bc5f0 184 * Use the V memory location, which is currently all 0, to initialize the
nexpaq 0:6c56fb4bc5f0 185 * MD context with an all-zero key. Then set V to its initial value.
nexpaq 0:6c56fb4bc5f0 186 */
nexpaq 0:6c56fb4bc5f0 187 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, md_size );
nexpaq 0:6c56fb4bc5f0 188 memset( ctx->V, 0x01, md_size );
nexpaq 0:6c56fb4bc5f0 189
nexpaq 0:6c56fb4bc5f0 190 ctx->f_entropy = f_entropy;
nexpaq 0:6c56fb4bc5f0 191 ctx->p_entropy = p_entropy;
nexpaq 0:6c56fb4bc5f0 192
nexpaq 0:6c56fb4bc5f0 193 ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL;
nexpaq 0:6c56fb4bc5f0 194
nexpaq 0:6c56fb4bc5f0 195 /*
nexpaq 0:6c56fb4bc5f0 196 * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by
nexpaq 0:6c56fb4bc5f0 197 * each hash function, then according to SP800-90A rev1 10.1 table 2,
nexpaq 0:6c56fb4bc5f0 198 * min_entropy_len (in bits) is security_strength.
nexpaq 0:6c56fb4bc5f0 199 *
nexpaq 0:6c56fb4bc5f0 200 * (This also matches the sizes used in the NIST test vectors.)
nexpaq 0:6c56fb4bc5f0 201 */
nexpaq 0:6c56fb4bc5f0 202 entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */
nexpaq 0:6c56fb4bc5f0 203 md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */
nexpaq 0:6c56fb4bc5f0 204 32; /* better (256+) -> 256 bits */
nexpaq 0:6c56fb4bc5f0 205
nexpaq 0:6c56fb4bc5f0 206 /*
nexpaq 0:6c56fb4bc5f0 207 * For initialisation, use more entropy to emulate a nonce
nexpaq 0:6c56fb4bc5f0 208 * (Again, matches test vectors.)
nexpaq 0:6c56fb4bc5f0 209 */
nexpaq 0:6c56fb4bc5f0 210 ctx->entropy_len = entropy_len * 3 / 2;
nexpaq 0:6c56fb4bc5f0 211
nexpaq 0:6c56fb4bc5f0 212 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, custom, len ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 213 return( ret );
nexpaq 0:6c56fb4bc5f0 214
nexpaq 0:6c56fb4bc5f0 215 ctx->entropy_len = entropy_len;
nexpaq 0:6c56fb4bc5f0 216
nexpaq 0:6c56fb4bc5f0 217 return( 0 );
nexpaq 0:6c56fb4bc5f0 218 }
nexpaq 0:6c56fb4bc5f0 219
nexpaq 0:6c56fb4bc5f0 220 /*
nexpaq 0:6c56fb4bc5f0 221 * Set prediction resistance
nexpaq 0:6c56fb4bc5f0 222 */
nexpaq 0:6c56fb4bc5f0 223 void mbedtls_hmac_drbg_set_prediction_resistance( mbedtls_hmac_drbg_context *ctx,
nexpaq 0:6c56fb4bc5f0 224 int resistance )
nexpaq 0:6c56fb4bc5f0 225 {
nexpaq 0:6c56fb4bc5f0 226 ctx->prediction_resistance = resistance;
nexpaq 0:6c56fb4bc5f0 227 }
nexpaq 0:6c56fb4bc5f0 228
nexpaq 0:6c56fb4bc5f0 229 /*
nexpaq 0:6c56fb4bc5f0 230 * Set entropy length grabbed for reseeds
nexpaq 0:6c56fb4bc5f0 231 */
nexpaq 0:6c56fb4bc5f0 232 void mbedtls_hmac_drbg_set_entropy_len( mbedtls_hmac_drbg_context *ctx, size_t len )
nexpaq 0:6c56fb4bc5f0 233 {
nexpaq 0:6c56fb4bc5f0 234 ctx->entropy_len = len;
nexpaq 0:6c56fb4bc5f0 235 }
nexpaq 0:6c56fb4bc5f0 236
nexpaq 0:6c56fb4bc5f0 237 /*
nexpaq 0:6c56fb4bc5f0 238 * Set reseed interval
nexpaq 0:6c56fb4bc5f0 239 */
nexpaq 0:6c56fb4bc5f0 240 void mbedtls_hmac_drbg_set_reseed_interval( mbedtls_hmac_drbg_context *ctx, int interval )
nexpaq 0:6c56fb4bc5f0 241 {
nexpaq 0:6c56fb4bc5f0 242 ctx->reseed_interval = interval;
nexpaq 0:6c56fb4bc5f0 243 }
nexpaq 0:6c56fb4bc5f0 244
nexpaq 0:6c56fb4bc5f0 245 /*
nexpaq 0:6c56fb4bc5f0 246 * HMAC_DRBG random function with optional additional data:
nexpaq 0:6c56fb4bc5f0 247 * 10.1.2.5 (arabic) + 9.3 (Roman)
nexpaq 0:6c56fb4bc5f0 248 */
nexpaq 0:6c56fb4bc5f0 249 int mbedtls_hmac_drbg_random_with_add( void *p_rng,
nexpaq 0:6c56fb4bc5f0 250 unsigned char *output, size_t out_len,
nexpaq 0:6c56fb4bc5f0 251 const unsigned char *additional, size_t add_len )
nexpaq 0:6c56fb4bc5f0 252 {
nexpaq 0:6c56fb4bc5f0 253 int ret;
nexpaq 0:6c56fb4bc5f0 254 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
nexpaq 0:6c56fb4bc5f0 255 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
nexpaq 0:6c56fb4bc5f0 256 size_t left = out_len;
nexpaq 0:6c56fb4bc5f0 257 unsigned char *out = output;
nexpaq 0:6c56fb4bc5f0 258
nexpaq 0:6c56fb4bc5f0 259 /* II. Check request length */
nexpaq 0:6c56fb4bc5f0 260 if( out_len > MBEDTLS_HMAC_DRBG_MAX_REQUEST )
nexpaq 0:6c56fb4bc5f0 261 return( MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG );
nexpaq 0:6c56fb4bc5f0 262
nexpaq 0:6c56fb4bc5f0 263 /* III. Check input length */
nexpaq 0:6c56fb4bc5f0 264 if( add_len > MBEDTLS_HMAC_DRBG_MAX_INPUT )
nexpaq 0:6c56fb4bc5f0 265 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
nexpaq 0:6c56fb4bc5f0 266
nexpaq 0:6c56fb4bc5f0 267 /* 1. (aka VII and IX) Check reseed counter and PR */
nexpaq 0:6c56fb4bc5f0 268 if( ctx->f_entropy != NULL && /* For no-reseeding instances */
nexpaq 0:6c56fb4bc5f0 269 ( ctx->prediction_resistance == MBEDTLS_HMAC_DRBG_PR_ON ||
nexpaq 0:6c56fb4bc5f0 270 ctx->reseed_counter > ctx->reseed_interval ) )
nexpaq 0:6c56fb4bc5f0 271 {
nexpaq 0:6c56fb4bc5f0 272 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, additional, add_len ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 273 return( ret );
nexpaq 0:6c56fb4bc5f0 274
nexpaq 0:6c56fb4bc5f0 275 add_len = 0; /* VII.4 */
nexpaq 0:6c56fb4bc5f0 276 }
nexpaq 0:6c56fb4bc5f0 277
nexpaq 0:6c56fb4bc5f0 278 /* 2. Use additional data if any */
nexpaq 0:6c56fb4bc5f0 279 if( additional != NULL && add_len != 0 )
nexpaq 0:6c56fb4bc5f0 280 mbedtls_hmac_drbg_update( ctx, additional, add_len );
nexpaq 0:6c56fb4bc5f0 281
nexpaq 0:6c56fb4bc5f0 282 /* 3, 4, 5. Generate bytes */
nexpaq 0:6c56fb4bc5f0 283 while( left != 0 )
nexpaq 0:6c56fb4bc5f0 284 {
nexpaq 0:6c56fb4bc5f0 285 size_t use_len = left > md_len ? md_len : left;
nexpaq 0:6c56fb4bc5f0 286
nexpaq 0:6c56fb4bc5f0 287 mbedtls_md_hmac_reset( &ctx->md_ctx );
nexpaq 0:6c56fb4bc5f0 288 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
nexpaq 0:6c56fb4bc5f0 289 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
nexpaq 0:6c56fb4bc5f0 290
nexpaq 0:6c56fb4bc5f0 291 memcpy( out, ctx->V, use_len );
nexpaq 0:6c56fb4bc5f0 292 out += use_len;
nexpaq 0:6c56fb4bc5f0 293 left -= use_len;
nexpaq 0:6c56fb4bc5f0 294 }
nexpaq 0:6c56fb4bc5f0 295
nexpaq 0:6c56fb4bc5f0 296 /* 6. Update */
nexpaq 0:6c56fb4bc5f0 297 mbedtls_hmac_drbg_update( ctx, additional, add_len );
nexpaq 0:6c56fb4bc5f0 298
nexpaq 0:6c56fb4bc5f0 299 /* 7. Update reseed counter */
nexpaq 0:6c56fb4bc5f0 300 ctx->reseed_counter++;
nexpaq 0:6c56fb4bc5f0 301
nexpaq 0:6c56fb4bc5f0 302 /* 8. Done */
nexpaq 0:6c56fb4bc5f0 303 return( 0 );
nexpaq 0:6c56fb4bc5f0 304 }
nexpaq 0:6c56fb4bc5f0 305
nexpaq 0:6c56fb4bc5f0 306 /*
nexpaq 0:6c56fb4bc5f0 307 * HMAC_DRBG random function
nexpaq 0:6c56fb4bc5f0 308 */
nexpaq 0:6c56fb4bc5f0 309 int mbedtls_hmac_drbg_random( void *p_rng, unsigned char *output, size_t out_len )
nexpaq 0:6c56fb4bc5f0 310 {
nexpaq 0:6c56fb4bc5f0 311 int ret;
nexpaq 0:6c56fb4bc5f0 312 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
nexpaq 0:6c56fb4bc5f0 313
nexpaq 0:6c56fb4bc5f0 314 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 315 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 316 return( ret );
nexpaq 0:6c56fb4bc5f0 317 #endif
nexpaq 0:6c56fb4bc5f0 318
nexpaq 0:6c56fb4bc5f0 319 ret = mbedtls_hmac_drbg_random_with_add( ctx, output, out_len, NULL, 0 );
nexpaq 0:6c56fb4bc5f0 320
nexpaq 0:6c56fb4bc5f0 321 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 322 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
nexpaq 0:6c56fb4bc5f0 323 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
nexpaq 0:6c56fb4bc5f0 324 #endif
nexpaq 0:6c56fb4bc5f0 325
nexpaq 0:6c56fb4bc5f0 326 return( ret );
nexpaq 0:6c56fb4bc5f0 327 }
nexpaq 0:6c56fb4bc5f0 328
nexpaq 0:6c56fb4bc5f0 329 /*
nexpaq 0:6c56fb4bc5f0 330 * Free an HMAC_DRBG context
nexpaq 0:6c56fb4bc5f0 331 */
nexpaq 0:6c56fb4bc5f0 332 void mbedtls_hmac_drbg_free( mbedtls_hmac_drbg_context *ctx )
nexpaq 0:6c56fb4bc5f0 333 {
nexpaq 0:6c56fb4bc5f0 334 if( ctx == NULL )
nexpaq 0:6c56fb4bc5f0 335 return;
nexpaq 0:6c56fb4bc5f0 336
nexpaq 0:6c56fb4bc5f0 337 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 338 mbedtls_mutex_free( &ctx->mutex );
nexpaq 0:6c56fb4bc5f0 339 #endif
nexpaq 0:6c56fb4bc5f0 340 mbedtls_md_free( &ctx->md_ctx );
nexpaq 0:6c56fb4bc5f0 341 mbedtls_zeroize( ctx, sizeof( mbedtls_hmac_drbg_context ) );
nexpaq 0:6c56fb4bc5f0 342 }
nexpaq 0:6c56fb4bc5f0 343
nexpaq 0:6c56fb4bc5f0 344 #if defined(MBEDTLS_FS_IO)
nexpaq 0:6c56fb4bc5f0 345 int mbedtls_hmac_drbg_write_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
nexpaq 0:6c56fb4bc5f0 346 {
nexpaq 0:6c56fb4bc5f0 347 int ret;
nexpaq 0:6c56fb4bc5f0 348 FILE *f;
nexpaq 0:6c56fb4bc5f0 349 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
nexpaq 0:6c56fb4bc5f0 350
nexpaq 0:6c56fb4bc5f0 351 if( ( f = fopen( path, "wb" ) ) == NULL )
nexpaq 0:6c56fb4bc5f0 352 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 353
nexpaq 0:6c56fb4bc5f0 354 if( ( ret = mbedtls_hmac_drbg_random( ctx, buf, sizeof( buf ) ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 355 goto exit;
nexpaq 0:6c56fb4bc5f0 356
nexpaq 0:6c56fb4bc5f0 357 if( fwrite( buf, 1, sizeof( buf ), f ) != sizeof( buf ) )
nexpaq 0:6c56fb4bc5f0 358 {
nexpaq 0:6c56fb4bc5f0 359 ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
nexpaq 0:6c56fb4bc5f0 360 goto exit;
nexpaq 0:6c56fb4bc5f0 361 }
nexpaq 0:6c56fb4bc5f0 362
nexpaq 0:6c56fb4bc5f0 363 ret = 0;
nexpaq 0:6c56fb4bc5f0 364
nexpaq 0:6c56fb4bc5f0 365 exit:
nexpaq 0:6c56fb4bc5f0 366 fclose( f );
nexpaq 0:6c56fb4bc5f0 367 return( ret );
nexpaq 0:6c56fb4bc5f0 368 }
nexpaq 0:6c56fb4bc5f0 369
nexpaq 0:6c56fb4bc5f0 370 int mbedtls_hmac_drbg_update_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
nexpaq 0:6c56fb4bc5f0 371 {
nexpaq 0:6c56fb4bc5f0 372 FILE *f;
nexpaq 0:6c56fb4bc5f0 373 size_t n;
nexpaq 0:6c56fb4bc5f0 374 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
nexpaq 0:6c56fb4bc5f0 375
nexpaq 0:6c56fb4bc5f0 376 if( ( f = fopen( path, "rb" ) ) == NULL )
nexpaq 0:6c56fb4bc5f0 377 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 378
nexpaq 0:6c56fb4bc5f0 379 fseek( f, 0, SEEK_END );
nexpaq 0:6c56fb4bc5f0 380 n = (size_t) ftell( f );
nexpaq 0:6c56fb4bc5f0 381 fseek( f, 0, SEEK_SET );
nexpaq 0:6c56fb4bc5f0 382
nexpaq 0:6c56fb4bc5f0 383 if( n > MBEDTLS_HMAC_DRBG_MAX_INPUT )
nexpaq 0:6c56fb4bc5f0 384 {
nexpaq 0:6c56fb4bc5f0 385 fclose( f );
nexpaq 0:6c56fb4bc5f0 386 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
nexpaq 0:6c56fb4bc5f0 387 }
nexpaq 0:6c56fb4bc5f0 388
nexpaq 0:6c56fb4bc5f0 389 if( fread( buf, 1, n, f ) != n )
nexpaq 0:6c56fb4bc5f0 390 {
nexpaq 0:6c56fb4bc5f0 391 fclose( f );
nexpaq 0:6c56fb4bc5f0 392 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 393 }
nexpaq 0:6c56fb4bc5f0 394
nexpaq 0:6c56fb4bc5f0 395 fclose( f );
nexpaq 0:6c56fb4bc5f0 396
nexpaq 0:6c56fb4bc5f0 397 mbedtls_hmac_drbg_update( ctx, buf, n );
nexpaq 0:6c56fb4bc5f0 398
nexpaq 0:6c56fb4bc5f0 399 return( mbedtls_hmac_drbg_write_seed_file( ctx, path ) );
nexpaq 0:6c56fb4bc5f0 400 }
nexpaq 0:6c56fb4bc5f0 401 #endif /* MBEDTLS_FS_IO */
nexpaq 0:6c56fb4bc5f0 402
nexpaq 0:6c56fb4bc5f0 403
nexpaq 0:6c56fb4bc5f0 404 #if defined(MBEDTLS_SELF_TEST)
nexpaq 0:6c56fb4bc5f0 405
nexpaq 0:6c56fb4bc5f0 406 #if !defined(MBEDTLS_SHA1_C)
nexpaq 0:6c56fb4bc5f0 407 /* Dummy checkup routine */
nexpaq 0:6c56fb4bc5f0 408 int mbedtls_hmac_drbg_self_test( int verbose )
nexpaq 0:6c56fb4bc5f0 409 {
nexpaq 0:6c56fb4bc5f0 410 (void) verbose;
nexpaq 0:6c56fb4bc5f0 411 return( 0 );
nexpaq 0:6c56fb4bc5f0 412 }
nexpaq 0:6c56fb4bc5f0 413 #else
nexpaq 0:6c56fb4bc5f0 414
nexpaq 0:6c56fb4bc5f0 415 #define OUTPUT_LEN 80
nexpaq 0:6c56fb4bc5f0 416
nexpaq 0:6c56fb4bc5f0 417 /* From a NIST PR=true test vector */
nexpaq 0:6c56fb4bc5f0 418 static const unsigned char entropy_pr[] = {
nexpaq 0:6c56fb4bc5f0 419 0xa0, 0xc9, 0xab, 0x58, 0xf1, 0xe2, 0xe5, 0xa4, 0xde, 0x3e, 0xbd, 0x4f,
nexpaq 0:6c56fb4bc5f0 420 0xf7, 0x3e, 0x9c, 0x5b, 0x64, 0xef, 0xd8, 0xca, 0x02, 0x8c, 0xf8, 0x11,
nexpaq 0:6c56fb4bc5f0 421 0x48, 0xa5, 0x84, 0xfe, 0x69, 0xab, 0x5a, 0xee, 0x42, 0xaa, 0x4d, 0x42,
nexpaq 0:6c56fb4bc5f0 422 0x17, 0x60, 0x99, 0xd4, 0x5e, 0x13, 0x97, 0xdc, 0x40, 0x4d, 0x86, 0xa3,
nexpaq 0:6c56fb4bc5f0 423 0x7b, 0xf5, 0x59, 0x54, 0x75, 0x69, 0x51, 0xe4 };
nexpaq 0:6c56fb4bc5f0 424 static const unsigned char result_pr[OUTPUT_LEN] = {
nexpaq 0:6c56fb4bc5f0 425 0x9a, 0x00, 0xa2, 0xd0, 0x0e, 0xd5, 0x9b, 0xfe, 0x31, 0xec, 0xb1, 0x39,
nexpaq 0:6c56fb4bc5f0 426 0x9b, 0x60, 0x81, 0x48, 0xd1, 0x96, 0x9d, 0x25, 0x0d, 0x3c, 0x1e, 0x94,
nexpaq 0:6c56fb4bc5f0 427 0x10, 0x10, 0x98, 0x12, 0x93, 0x25, 0xca, 0xb8, 0xfc, 0xcc, 0x2d, 0x54,
nexpaq 0:6c56fb4bc5f0 428 0x73, 0x19, 0x70, 0xc0, 0x10, 0x7a, 0xa4, 0x89, 0x25, 0x19, 0x95, 0x5e,
nexpaq 0:6c56fb4bc5f0 429 0x4b, 0xc6, 0x00, 0x1d, 0x7f, 0x4e, 0x6a, 0x2b, 0xf8, 0xa3, 0x01, 0xab,
nexpaq 0:6c56fb4bc5f0 430 0x46, 0x05, 0x5c, 0x09, 0xa6, 0x71, 0x88, 0xf1, 0xa7, 0x40, 0xee, 0xf3,
nexpaq 0:6c56fb4bc5f0 431 0xe1, 0x5c, 0x02, 0x9b, 0x44, 0xaf, 0x03, 0x44 };
nexpaq 0:6c56fb4bc5f0 432
nexpaq 0:6c56fb4bc5f0 433 /* From a NIST PR=false test vector */
nexpaq 0:6c56fb4bc5f0 434 static const unsigned char entropy_nopr[] = {
nexpaq 0:6c56fb4bc5f0 435 0x79, 0x34, 0x9b, 0xbf, 0x7c, 0xdd, 0xa5, 0x79, 0x95, 0x57, 0x86, 0x66,
nexpaq 0:6c56fb4bc5f0 436 0x21, 0xc9, 0x13, 0x83, 0x11, 0x46, 0x73, 0x3a, 0xbf, 0x8c, 0x35, 0xc8,
nexpaq 0:6c56fb4bc5f0 437 0xc7, 0x21, 0x5b, 0x5b, 0x96, 0xc4, 0x8e, 0x9b, 0x33, 0x8c, 0x74, 0xe3,
nexpaq 0:6c56fb4bc5f0 438 0xe9, 0x9d, 0xfe, 0xdf };
nexpaq 0:6c56fb4bc5f0 439 static const unsigned char result_nopr[OUTPUT_LEN] = {
nexpaq 0:6c56fb4bc5f0 440 0xc6, 0xa1, 0x6a, 0xb8, 0xd4, 0x20, 0x70, 0x6f, 0x0f, 0x34, 0xab, 0x7f,
nexpaq 0:6c56fb4bc5f0 441 0xec, 0x5a, 0xdc, 0xa9, 0xd8, 0xca, 0x3a, 0x13, 0x3e, 0x15, 0x9c, 0xa6,
nexpaq 0:6c56fb4bc5f0 442 0xac, 0x43, 0xc6, 0xf8, 0xa2, 0xbe, 0x22, 0x83, 0x4a, 0x4c, 0x0a, 0x0a,
nexpaq 0:6c56fb4bc5f0 443 0xff, 0xb1, 0x0d, 0x71, 0x94, 0xf1, 0xc1, 0xa5, 0xcf, 0x73, 0x22, 0xec,
nexpaq 0:6c56fb4bc5f0 444 0x1a, 0xe0, 0x96, 0x4e, 0xd4, 0xbf, 0x12, 0x27, 0x46, 0xe0, 0x87, 0xfd,
nexpaq 0:6c56fb4bc5f0 445 0xb5, 0xb3, 0xe9, 0x1b, 0x34, 0x93, 0xd5, 0xbb, 0x98, 0xfa, 0xed, 0x49,
nexpaq 0:6c56fb4bc5f0 446 0xe8, 0x5f, 0x13, 0x0f, 0xc8, 0xa4, 0x59, 0xb7 };
nexpaq 0:6c56fb4bc5f0 447
nexpaq 0:6c56fb4bc5f0 448 /* "Entropy" from buffer */
nexpaq 0:6c56fb4bc5f0 449 static size_t test_offset;
nexpaq 0:6c56fb4bc5f0 450 static int hmac_drbg_self_test_entropy( void *data,
nexpaq 0:6c56fb4bc5f0 451 unsigned char *buf, size_t len )
nexpaq 0:6c56fb4bc5f0 452 {
nexpaq 0:6c56fb4bc5f0 453 const unsigned char *p = data;
nexpaq 0:6c56fb4bc5f0 454 memcpy( buf, p + test_offset, len );
nexpaq 0:6c56fb4bc5f0 455 test_offset += len;
nexpaq 0:6c56fb4bc5f0 456 return( 0 );
nexpaq 0:6c56fb4bc5f0 457 }
nexpaq 0:6c56fb4bc5f0 458
nexpaq 0:6c56fb4bc5f0 459 #define CHK( c ) if( (c) != 0 ) \
nexpaq 0:6c56fb4bc5f0 460 { \
nexpaq 0:6c56fb4bc5f0 461 if( verbose != 0 ) \
nexpaq 0:6c56fb4bc5f0 462 mbedtls_printf( "failed\n" ); \
nexpaq 0:6c56fb4bc5f0 463 return( 1 ); \
nexpaq 0:6c56fb4bc5f0 464 }
nexpaq 0:6c56fb4bc5f0 465
nexpaq 0:6c56fb4bc5f0 466 /*
nexpaq 0:6c56fb4bc5f0 467 * Checkup routine for HMAC_DRBG with SHA-1
nexpaq 0:6c56fb4bc5f0 468 */
nexpaq 0:6c56fb4bc5f0 469 int mbedtls_hmac_drbg_self_test( int verbose )
nexpaq 0:6c56fb4bc5f0 470 {
nexpaq 0:6c56fb4bc5f0 471 mbedtls_hmac_drbg_context ctx;
nexpaq 0:6c56fb4bc5f0 472 unsigned char buf[OUTPUT_LEN];
nexpaq 0:6c56fb4bc5f0 473 const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
nexpaq 0:6c56fb4bc5f0 474
nexpaq 0:6c56fb4bc5f0 475 mbedtls_hmac_drbg_init( &ctx );
nexpaq 0:6c56fb4bc5f0 476
nexpaq 0:6c56fb4bc5f0 477 /*
nexpaq 0:6c56fb4bc5f0 478 * PR = True
nexpaq 0:6c56fb4bc5f0 479 */
nexpaq 0:6c56fb4bc5f0 480 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 481 mbedtls_printf( " HMAC_DRBG (PR = True) : " );
nexpaq 0:6c56fb4bc5f0 482
nexpaq 0:6c56fb4bc5f0 483 test_offset = 0;
nexpaq 0:6c56fb4bc5f0 484 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
nexpaq 0:6c56fb4bc5f0 485 hmac_drbg_self_test_entropy, (void *) entropy_pr,
nexpaq 0:6c56fb4bc5f0 486 NULL, 0 ) );
nexpaq 0:6c56fb4bc5f0 487 mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
nexpaq 0:6c56fb4bc5f0 488 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
nexpaq 0:6c56fb4bc5f0 489 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
nexpaq 0:6c56fb4bc5f0 490 CHK( memcmp( buf, result_pr, OUTPUT_LEN ) );
nexpaq 0:6c56fb4bc5f0 491 mbedtls_hmac_drbg_free( &ctx );
nexpaq 0:6c56fb4bc5f0 492
nexpaq 0:6c56fb4bc5f0 493 mbedtls_hmac_drbg_free( &ctx );
nexpaq 0:6c56fb4bc5f0 494
nexpaq 0:6c56fb4bc5f0 495 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 496 mbedtls_printf( "passed\n" );
nexpaq 0:6c56fb4bc5f0 497
nexpaq 0:6c56fb4bc5f0 498 /*
nexpaq 0:6c56fb4bc5f0 499 * PR = False
nexpaq 0:6c56fb4bc5f0 500 */
nexpaq 0:6c56fb4bc5f0 501 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 502 mbedtls_printf( " HMAC_DRBG (PR = False) : " );
nexpaq 0:6c56fb4bc5f0 503
nexpaq 0:6c56fb4bc5f0 504 mbedtls_hmac_drbg_init( &ctx );
nexpaq 0:6c56fb4bc5f0 505
nexpaq 0:6c56fb4bc5f0 506 test_offset = 0;
nexpaq 0:6c56fb4bc5f0 507 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
nexpaq 0:6c56fb4bc5f0 508 hmac_drbg_self_test_entropy, (void *) entropy_nopr,
nexpaq 0:6c56fb4bc5f0 509 NULL, 0 ) );
nexpaq 0:6c56fb4bc5f0 510 CHK( mbedtls_hmac_drbg_reseed( &ctx, NULL, 0 ) );
nexpaq 0:6c56fb4bc5f0 511 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
nexpaq 0:6c56fb4bc5f0 512 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
nexpaq 0:6c56fb4bc5f0 513 CHK( memcmp( buf, result_nopr, OUTPUT_LEN ) );
nexpaq 0:6c56fb4bc5f0 514 mbedtls_hmac_drbg_free( &ctx );
nexpaq 0:6c56fb4bc5f0 515
nexpaq 0:6c56fb4bc5f0 516 mbedtls_hmac_drbg_free( &ctx );
nexpaq 0:6c56fb4bc5f0 517
nexpaq 0:6c56fb4bc5f0 518 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 519 mbedtls_printf( "passed\n" );
nexpaq 0:6c56fb4bc5f0 520
nexpaq 0:6c56fb4bc5f0 521 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 522 mbedtls_printf( "\n" );
nexpaq 0:6c56fb4bc5f0 523
nexpaq 0:6c56fb4bc5f0 524 return( 0 );
nexpaq 0:6c56fb4bc5f0 525 }
nexpaq 0:6c56fb4bc5f0 526 #endif /* MBEDTLS_SHA1_C */
nexpaq 0:6c56fb4bc5f0 527 #endif /* MBEDTLS_SELF_TEST */
nexpaq 0:6c56fb4bc5f0 528
nexpaq 0:6c56fb4bc5f0 529 #endif /* MBEDTLS_HMAC_DRBG_C */