Kev Mann / mbed-dev-OS5_10_4

RTC auf true

features/mbedtls/src/hmac_drbg.c@2:7aab896b1a3b, 2019-03-13 (annotated)

Committer:
kevman
Date:
Wed Mar 13 11:03:24 2019 +0000
Revision:
2:7aab896b1a3b
Parent:
0:38ceb79fef03 
2019-03-13

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kevman 0:38ceb79fef03 1 /*
kevman 0:38ceb79fef03 2 * HMAC_DRBG implementation (NIST SP 800-90)
kevman 0:38ceb79fef03 3 *
kevman 0:38ceb79fef03 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
kevman 0:38ceb79fef03 5 * SPDX-License-Identifier: Apache-2.0
kevman 0:38ceb79fef03 6 *
kevman 0:38ceb79fef03 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
kevman 0:38ceb79fef03 8 * not use this file except in compliance with the License.
kevman 0:38ceb79fef03 9 * You may obtain a copy of the License at
kevman 0:38ceb79fef03 10 *
kevman 0:38ceb79fef03 11 * http://www.apache.org/licenses/LICENSE-2.0
kevman 0:38ceb79fef03 12 *
kevman 0:38ceb79fef03 13 * Unless required by applicable law or agreed to in writing, software
kevman 0:38ceb79fef03 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
kevman 0:38ceb79fef03 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
kevman 0:38ceb79fef03 16 * See the License for the specific language governing permissions and
kevman 0:38ceb79fef03 17 * limitations under the License.
kevman 0:38ceb79fef03 18 *
kevman 0:38ceb79fef03 19 * This file is part of mbed TLS (https://tls.mbed.org)
kevman 0:38ceb79fef03 20 */
kevman 0:38ceb79fef03 21
kevman 0:38ceb79fef03 22 /*
kevman 0:38ceb79fef03 23 * The NIST SP 800-90A DRBGs are described in the following publication.
kevman 0:38ceb79fef03 24 * http://csrc.nist.gov/publications/nistpubs/800-90A/SP800-90A.pdf
kevman 0:38ceb79fef03 25 * References below are based on rev. 1 (January 2012).
kevman 0:38ceb79fef03 26 */
kevman 0:38ceb79fef03 27
kevman 0:38ceb79fef03 28 #if !defined(MBEDTLS_CONFIG_FILE)
kevman 0:38ceb79fef03 29 #include "mbedtls/config.h"
kevman 0:38ceb79fef03 30 #else
kevman 0:38ceb79fef03 31 #include MBEDTLS_CONFIG_FILE
kevman 0:38ceb79fef03 32 #endif
kevman 0:38ceb79fef03 33
kevman 0:38ceb79fef03 34 #if defined(MBEDTLS_HMAC_DRBG_C)
kevman 0:38ceb79fef03 35
kevman 0:38ceb79fef03 36 #include "mbedtls/hmac_drbg.h"
kevman 0:38ceb79fef03 37 #include "mbedtls/platform_util.h"
kevman 0:38ceb79fef03 38
kevman 0:38ceb79fef03 39 #include <string.h>
kevman 0:38ceb79fef03 40
kevman 0:38ceb79fef03 41 #if defined(MBEDTLS_FS_IO)
kevman 0:38ceb79fef03 42 #include <stdio.h>
kevman 0:38ceb79fef03 43 #endif
kevman 0:38ceb79fef03 44
kevman 0:38ceb79fef03 45 #if defined(MBEDTLS_SELF_TEST)
kevman 0:38ceb79fef03 46 #if defined(MBEDTLS_PLATFORM_C)
kevman 0:38ceb79fef03 47 #include "mbedtls/platform.h"
kevman 0:38ceb79fef03 48 #else
kevman 0:38ceb79fef03 49 #include <stdio.h>
kevman 0:38ceb79fef03 50 #define mbedtls_printf printf
kevman 0:38ceb79fef03 51 #endif /* MBEDTLS_SELF_TEST */
kevman 0:38ceb79fef03 52 #endif /* MBEDTLS_PLATFORM_C */
kevman 0:38ceb79fef03 53
kevman 0:38ceb79fef03 54 /*
kevman 0:38ceb79fef03 55 * HMAC_DRBG context initialization
kevman 0:38ceb79fef03 56 */
kevman 0:38ceb79fef03 57 void mbedtls_hmac_drbg_init( mbedtls_hmac_drbg_context *ctx )
kevman 0:38ceb79fef03 58 {
kevman 0:38ceb79fef03 59 memset( ctx, 0, sizeof( mbedtls_hmac_drbg_context ) );
kevman 0:38ceb79fef03 60
kevman 0:38ceb79fef03 61 #if defined(MBEDTLS_THREADING_C)
kevman 0:38ceb79fef03 62 mbedtls_mutex_init( &ctx->mutex );
kevman 0:38ceb79fef03 63 #endif
kevman 0:38ceb79fef03 64 }
kevman 0:38ceb79fef03 65
kevman 0:38ceb79fef03 66 /*
kevman 0:38ceb79fef03 67 * HMAC_DRBG update, using optional additional data (10.1.2.2)
kevman 0:38ceb79fef03 68 */
kevman 0:38ceb79fef03 69 void mbedtls_hmac_drbg_update( mbedtls_hmac_drbg_context *ctx,
kevman 0:38ceb79fef03 70 const unsigned char *additional, size_t add_len )
kevman 0:38ceb79fef03 71 {
kevman 0:38ceb79fef03 72 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
kevman 0:38ceb79fef03 73 unsigned char rounds = ( additional != NULL && add_len != 0 ) ? 2 : 1;
kevman 0:38ceb79fef03 74 unsigned char sep[1];
kevman 0:38ceb79fef03 75 unsigned char K[MBEDTLS_MD_MAX_SIZE];
kevman 0:38ceb79fef03 76
kevman 0:38ceb79fef03 77 for( sep[0] = 0; sep[0] < rounds; sep[0]++ )
kevman 0:38ceb79fef03 78 {
kevman 0:38ceb79fef03 79 /* Step 1 or 4 */
kevman 0:38ceb79fef03 80 mbedtls_md_hmac_reset( &ctx->md_ctx );
kevman 0:38ceb79fef03 81 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
kevman 0:38ceb79fef03 82 mbedtls_md_hmac_update( &ctx->md_ctx, sep, 1 );
kevman 0:38ceb79fef03 83 if( rounds == 2 )
kevman 0:38ceb79fef03 84 mbedtls_md_hmac_update( &ctx->md_ctx, additional, add_len );
kevman 0:38ceb79fef03 85 mbedtls_md_hmac_finish( &ctx->md_ctx, K );
kevman 0:38ceb79fef03 86
kevman 0:38ceb79fef03 87 /* Step 2 or 5 */
kevman 0:38ceb79fef03 88 mbedtls_md_hmac_starts( &ctx->md_ctx, K, md_len );
kevman 0:38ceb79fef03 89 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
kevman 0:38ceb79fef03 90 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
kevman 0:38ceb79fef03 91 }
kevman 0:38ceb79fef03 92 }
kevman 0:38ceb79fef03 93
kevman 0:38ceb79fef03 94 /*
kevman 0:38ceb79fef03 95 * Simplified HMAC_DRBG initialisation (for use with deterministic ECDSA)
kevman 0:38ceb79fef03 96 */
kevman 0:38ceb79fef03 97 int mbedtls_hmac_drbg_seed_buf( mbedtls_hmac_drbg_context *ctx,
kevman 0:38ceb79fef03 98 const mbedtls_md_info_t * md_info,
kevman 0:38ceb79fef03 99 const unsigned char *data, size_t data_len )
kevman 0:38ceb79fef03 100 {
kevman 0:38ceb79fef03 101 int ret;
kevman 0:38ceb79fef03 102
kevman 0:38ceb79fef03 103 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
kevman 0:38ceb79fef03 104 return( ret );
kevman 0:38ceb79fef03 105
kevman 0:38ceb79fef03 106 /*
kevman 0:38ceb79fef03 107 * Set initial working state.
kevman 0:38ceb79fef03 108 * Use the V memory location, which is currently all 0, to initialize the
kevman 0:38ceb79fef03 109 * MD context with an all-zero key. Then set V to its initial value.
kevman 0:38ceb79fef03 110 */
kevman 0:38ceb79fef03 111 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, mbedtls_md_get_size( md_info ) );
kevman 0:38ceb79fef03 112 memset( ctx->V, 0x01, mbedtls_md_get_size( md_info ) );
kevman 0:38ceb79fef03 113
kevman 0:38ceb79fef03 114 mbedtls_hmac_drbg_update( ctx, data, data_len );
kevman 0:38ceb79fef03 115
kevman 0:38ceb79fef03 116 return( 0 );
kevman 0:38ceb79fef03 117 }
kevman 0:38ceb79fef03 118
kevman 0:38ceb79fef03 119 /*
kevman 0:38ceb79fef03 120 * HMAC_DRBG reseeding: 10.1.2.4 (arabic) + 9.2 (Roman)
kevman 0:38ceb79fef03 121 */
kevman 0:38ceb79fef03 122 int mbedtls_hmac_drbg_reseed( mbedtls_hmac_drbg_context *ctx,
kevman 0:38ceb79fef03 123 const unsigned char *additional, size_t len )
kevman 0:38ceb79fef03 124 {
kevman 0:38ceb79fef03 125 unsigned char seed[MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT];
kevman 0:38ceb79fef03 126 size_t seedlen;
kevman 0:38ceb79fef03 127
kevman 0:38ceb79fef03 128 /* III. Check input length */
kevman 0:38ceb79fef03 129 if( len > MBEDTLS_HMAC_DRBG_MAX_INPUT ||
kevman 0:38ceb79fef03 130 ctx->entropy_len + len > MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT )
kevman 0:38ceb79fef03 131 {
kevman 0:38ceb79fef03 132 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
kevman 0:38ceb79fef03 133 }
kevman 0:38ceb79fef03 134
kevman 0:38ceb79fef03 135 memset( seed, 0, MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT );
kevman 0:38ceb79fef03 136
kevman 0:38ceb79fef03 137 /* IV. Gather entropy_len bytes of entropy for the seed */
kevman 0:38ceb79fef03 138 if( ctx->f_entropy( ctx->p_entropy, seed, ctx->entropy_len ) != 0 )
kevman 0:38ceb79fef03 139 return( MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED );
kevman 0:38ceb79fef03 140
kevman 0:38ceb79fef03 141 seedlen = ctx->entropy_len;
kevman 0:38ceb79fef03 142
kevman 0:38ceb79fef03 143 /* 1. Concatenate entropy and additional data if any */
kevman 0:38ceb79fef03 144 if( additional != NULL && len != 0 )
kevman 0:38ceb79fef03 145 {
kevman 0:38ceb79fef03 146 memcpy( seed + seedlen, additional, len );
kevman 0:38ceb79fef03 147 seedlen += len;
kevman 0:38ceb79fef03 148 }
kevman 0:38ceb79fef03 149
kevman 0:38ceb79fef03 150 /* 2. Update state */
kevman 0:38ceb79fef03 151 mbedtls_hmac_drbg_update( ctx, seed, seedlen );
kevman 0:38ceb79fef03 152
kevman 0:38ceb79fef03 153 /* 3. Reset reseed_counter */
kevman 0:38ceb79fef03 154 ctx->reseed_counter = 1;
kevman 0:38ceb79fef03 155
kevman 0:38ceb79fef03 156 /* 4. Done */
kevman 0:38ceb79fef03 157 return( 0 );
kevman 0:38ceb79fef03 158 }
kevman 0:38ceb79fef03 159
kevman 0:38ceb79fef03 160 /*
kevman 0:38ceb79fef03 161 * HMAC_DRBG initialisation (10.1.2.3 + 9.1)
kevman 0:38ceb79fef03 162 */
kevman 0:38ceb79fef03 163 int mbedtls_hmac_drbg_seed( mbedtls_hmac_drbg_context *ctx,
kevman 0:38ceb79fef03 164 const mbedtls_md_info_t * md_info,
kevman 0:38ceb79fef03 165 int (*f_entropy)(void *, unsigned char *, size_t),
kevman 0:38ceb79fef03 166 void *p_entropy,
kevman 0:38ceb79fef03 167 const unsigned char *custom,
kevman 0:38ceb79fef03 168 size_t len )
kevman 0:38ceb79fef03 169 {
kevman 0:38ceb79fef03 170 int ret;
kevman 0:38ceb79fef03 171 size_t entropy_len, md_size;
kevman 0:38ceb79fef03 172
kevman 0:38ceb79fef03 173 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
kevman 0:38ceb79fef03 174 return( ret );
kevman 0:38ceb79fef03 175
kevman 0:38ceb79fef03 176 md_size = mbedtls_md_get_size( md_info );
kevman 0:38ceb79fef03 177
kevman 0:38ceb79fef03 178 /*
kevman 0:38ceb79fef03 179 * Set initial working state.
kevman 0:38ceb79fef03 180 * Use the V memory location, which is currently all 0, to initialize the
kevman 0:38ceb79fef03 181 * MD context with an all-zero key. Then set V to its initial value.
kevman 0:38ceb79fef03 182 */
kevman 0:38ceb79fef03 183 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, md_size );
kevman 0:38ceb79fef03 184 memset( ctx->V, 0x01, md_size );
kevman 0:38ceb79fef03 185
kevman 0:38ceb79fef03 186 ctx->f_entropy = f_entropy;
kevman 0:38ceb79fef03 187 ctx->p_entropy = p_entropy;
kevman 0:38ceb79fef03 188
kevman 0:38ceb79fef03 189 ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL;
kevman 0:38ceb79fef03 190
kevman 0:38ceb79fef03 191 /*
kevman 0:38ceb79fef03 192 * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by
kevman 0:38ceb79fef03 193 * each hash function, then according to SP800-90A rev1 10.1 table 2,
kevman 0:38ceb79fef03 194 * min_entropy_len (in bits) is security_strength.
kevman 0:38ceb79fef03 195 *
kevman 0:38ceb79fef03 196 * (This also matches the sizes used in the NIST test vectors.)
kevman 0:38ceb79fef03 197 */
kevman 0:38ceb79fef03 198 entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */
kevman 0:38ceb79fef03 199 md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */
kevman 0:38ceb79fef03 200 32; /* better (256+) -> 256 bits */
kevman 0:38ceb79fef03 201
kevman 0:38ceb79fef03 202 /*
kevman 0:38ceb79fef03 203 * For initialisation, use more entropy to emulate a nonce
kevman 0:38ceb79fef03 204 * (Again, matches test vectors.)
kevman 0:38ceb79fef03 205 */
kevman 0:38ceb79fef03 206 ctx->entropy_len = entropy_len * 3 / 2;
kevman 0:38ceb79fef03 207
kevman 0:38ceb79fef03 208 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, custom, len ) ) != 0 )
kevman 0:38ceb79fef03 209 return( ret );
kevman 0:38ceb79fef03 210
kevman 0:38ceb79fef03 211 ctx->entropy_len = entropy_len;
kevman 0:38ceb79fef03 212
kevman 0:38ceb79fef03 213 return( 0 );
kevman 0:38ceb79fef03 214 }
kevman 0:38ceb79fef03 215
kevman 0:38ceb79fef03 216 /*
kevman 0:38ceb79fef03 217 * Set prediction resistance
kevman 0:38ceb79fef03 218 */
kevman 0:38ceb79fef03 219 void mbedtls_hmac_drbg_set_prediction_resistance( mbedtls_hmac_drbg_context *ctx,
kevman 0:38ceb79fef03 220 int resistance )
kevman 0:38ceb79fef03 221 {
kevman 0:38ceb79fef03 222 ctx->prediction_resistance = resistance;
kevman 0:38ceb79fef03 223 }
kevman 0:38ceb79fef03 224
kevman 0:38ceb79fef03 225 /*
kevman 0:38ceb79fef03 226 * Set entropy length grabbed for reseeds
kevman 0:38ceb79fef03 227 */
kevman 0:38ceb79fef03 228 void mbedtls_hmac_drbg_set_entropy_len( mbedtls_hmac_drbg_context *ctx, size_t len )
kevman 0:38ceb79fef03 229 {
kevman 0:38ceb79fef03 230 ctx->entropy_len = len;
kevman 0:38ceb79fef03 231 }
kevman 0:38ceb79fef03 232
kevman 0:38ceb79fef03 233 /*
kevman 0:38ceb79fef03 234 * Set reseed interval
kevman 0:38ceb79fef03 235 */
kevman 0:38ceb79fef03 236 void mbedtls_hmac_drbg_set_reseed_interval( mbedtls_hmac_drbg_context *ctx, int interval )
kevman 0:38ceb79fef03 237 {
kevman 0:38ceb79fef03 238 ctx->reseed_interval = interval;
kevman 0:38ceb79fef03 239 }
kevman 0:38ceb79fef03 240
kevman 0:38ceb79fef03 241 /*
kevman 0:38ceb79fef03 242 * HMAC_DRBG random function with optional additional data:
kevman 0:38ceb79fef03 243 * 10.1.2.5 (arabic) + 9.3 (Roman)
kevman 0:38ceb79fef03 244 */
kevman 0:38ceb79fef03 245 int mbedtls_hmac_drbg_random_with_add( void *p_rng,
kevman 0:38ceb79fef03 246 unsigned char *output, size_t out_len,
kevman 0:38ceb79fef03 247 const unsigned char *additional, size_t add_len )
kevman 0:38ceb79fef03 248 {
kevman 0:38ceb79fef03 249 int ret;
kevman 0:38ceb79fef03 250 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
kevman 0:38ceb79fef03 251 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
kevman 0:38ceb79fef03 252 size_t left = out_len;
kevman 0:38ceb79fef03 253 unsigned char *out = output;
kevman 0:38ceb79fef03 254
kevman 0:38ceb79fef03 255 /* II. Check request length */
kevman 0:38ceb79fef03 256 if( out_len > MBEDTLS_HMAC_DRBG_MAX_REQUEST )
kevman 0:38ceb79fef03 257 return( MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG );
kevman 0:38ceb79fef03 258
kevman 0:38ceb79fef03 259 /* III. Check input length */
kevman 0:38ceb79fef03 260 if( add_len > MBEDTLS_HMAC_DRBG_MAX_INPUT )
kevman 0:38ceb79fef03 261 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
kevman 0:38ceb79fef03 262
kevman 0:38ceb79fef03 263 /* 1. (aka VII and IX) Check reseed counter and PR */
kevman 0:38ceb79fef03 264 if( ctx->f_entropy != NULL && /* For no-reseeding instances */
kevman 0:38ceb79fef03 265 ( ctx->prediction_resistance == MBEDTLS_HMAC_DRBG_PR_ON ||
kevman 0:38ceb79fef03 266 ctx->reseed_counter > ctx->reseed_interval ) )
kevman 0:38ceb79fef03 267 {
kevman 0:38ceb79fef03 268 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, additional, add_len ) ) != 0 )
kevman 0:38ceb79fef03 269 return( ret );
kevman 0:38ceb79fef03 270
kevman 0:38ceb79fef03 271 add_len = 0; /* VII.4 */
kevman 0:38ceb79fef03 272 }
kevman 0:38ceb79fef03 273
kevman 0:38ceb79fef03 274 /* 2. Use additional data if any */
kevman 0:38ceb79fef03 275 if( additional != NULL && add_len != 0 )
kevman 0:38ceb79fef03 276 mbedtls_hmac_drbg_update( ctx, additional, add_len );
kevman 0:38ceb79fef03 277
kevman 0:38ceb79fef03 278 /* 3, 4, 5. Generate bytes */
kevman 0:38ceb79fef03 279 while( left != 0 )
kevman 0:38ceb79fef03 280 {
kevman 0:38ceb79fef03 281 size_t use_len = left > md_len ? md_len : left;
kevman 0:38ceb79fef03 282
kevman 0:38ceb79fef03 283 mbedtls_md_hmac_reset( &ctx->md_ctx );
kevman 0:38ceb79fef03 284 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
kevman 0:38ceb79fef03 285 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
kevman 0:38ceb79fef03 286
kevman 0:38ceb79fef03 287 memcpy( out, ctx->V, use_len );
kevman 0:38ceb79fef03 288 out += use_len;
kevman 0:38ceb79fef03 289 left -= use_len;
kevman 0:38ceb79fef03 290 }
kevman 0:38ceb79fef03 291
kevman 0:38ceb79fef03 292 /* 6. Update */
kevman 0:38ceb79fef03 293 mbedtls_hmac_drbg_update( ctx, additional, add_len );
kevman 0:38ceb79fef03 294
kevman 0:38ceb79fef03 295 /* 7. Update reseed counter */
kevman 0:38ceb79fef03 296 ctx->reseed_counter++;
kevman 0:38ceb79fef03 297
kevman 0:38ceb79fef03 298 /* 8. Done */
kevman 0:38ceb79fef03 299 return( 0 );
kevman 0:38ceb79fef03 300 }
kevman 0:38ceb79fef03 301
kevman 0:38ceb79fef03 302 /*
kevman 0:38ceb79fef03 303 * HMAC_DRBG random function
kevman 0:38ceb79fef03 304 */
kevman 0:38ceb79fef03 305 int mbedtls_hmac_drbg_random( void *p_rng, unsigned char *output, size_t out_len )
kevman 0:38ceb79fef03 306 {
kevman 0:38ceb79fef03 307 int ret;
kevman 0:38ceb79fef03 308 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
kevman 0:38ceb79fef03 309
kevman 0:38ceb79fef03 310 #if defined(MBEDTLS_THREADING_C)
kevman 0:38ceb79fef03 311 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
kevman 0:38ceb79fef03 312 return( ret );
kevman 0:38ceb79fef03 313 #endif
kevman 0:38ceb79fef03 314
kevman 0:38ceb79fef03 315 ret = mbedtls_hmac_drbg_random_with_add( ctx, output, out_len, NULL, 0 );
kevman 0:38ceb79fef03 316
kevman 0:38ceb79fef03 317 #if defined(MBEDTLS_THREADING_C)
kevman 0:38ceb79fef03 318 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
kevman 0:38ceb79fef03 319 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
kevman 0:38ceb79fef03 320 #endif
kevman 0:38ceb79fef03 321
kevman 0:38ceb79fef03 322 return( ret );
kevman 0:38ceb79fef03 323 }
kevman 0:38ceb79fef03 324
kevman 0:38ceb79fef03 325 /*
kevman 0:38ceb79fef03 326 * Free an HMAC_DRBG context
kevman 0:38ceb79fef03 327 */
kevman 0:38ceb79fef03 328 void mbedtls_hmac_drbg_free( mbedtls_hmac_drbg_context *ctx )
kevman 0:38ceb79fef03 329 {
kevman 0:38ceb79fef03 330 if( ctx == NULL )
kevman 0:38ceb79fef03 331 return;
kevman 0:38ceb79fef03 332
kevman 0:38ceb79fef03 333 #if defined(MBEDTLS_THREADING_C)
kevman 0:38ceb79fef03 334 mbedtls_mutex_free( &ctx->mutex );
kevman 0:38ceb79fef03 335 #endif
kevman 0:38ceb79fef03 336 mbedtls_md_free( &ctx->md_ctx );
kevman 0:38ceb79fef03 337 mbedtls_platform_zeroize( ctx, sizeof( mbedtls_hmac_drbg_context ) );
kevman 0:38ceb79fef03 338 }
kevman 0:38ceb79fef03 339
kevman 0:38ceb79fef03 340 #if defined(MBEDTLS_FS_IO)
kevman 0:38ceb79fef03 341 int mbedtls_hmac_drbg_write_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
kevman 0:38ceb79fef03 342 {
kevman 0:38ceb79fef03 343 int ret;
kevman 0:38ceb79fef03 344 FILE *f;
kevman 0:38ceb79fef03 345 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
kevman 0:38ceb79fef03 346
kevman 0:38ceb79fef03 347 if( ( f = fopen( path, "wb" ) ) == NULL )
kevman 0:38ceb79fef03 348 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
kevman 0:38ceb79fef03 349
kevman 0:38ceb79fef03 350 if( ( ret = mbedtls_hmac_drbg_random( ctx, buf, sizeof( buf ) ) ) != 0 )
kevman 0:38ceb79fef03 351 goto exit;
kevman 0:38ceb79fef03 352
kevman 0:38ceb79fef03 353 if( fwrite( buf, 1, sizeof( buf ), f ) != sizeof( buf ) )
kevman 0:38ceb79fef03 354 {
kevman 0:38ceb79fef03 355 ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
kevman 0:38ceb79fef03 356 goto exit;
kevman 0:38ceb79fef03 357 }
kevman 0:38ceb79fef03 358
kevman 0:38ceb79fef03 359 ret = 0;
kevman 0:38ceb79fef03 360
kevman 0:38ceb79fef03 361 exit:
kevman 0:38ceb79fef03 362 fclose( f );
kevman 0:38ceb79fef03 363 mbedtls_platform_zeroize( buf, sizeof( buf ) );
kevman 0:38ceb79fef03 364
kevman 0:38ceb79fef03 365 return( ret );
kevman 0:38ceb79fef03 366 }
kevman 0:38ceb79fef03 367
kevman 0:38ceb79fef03 368 int mbedtls_hmac_drbg_update_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
kevman 0:38ceb79fef03 369 {
kevman 0:38ceb79fef03 370 int ret = 0;
kevman 0:38ceb79fef03 371 FILE *f;
kevman 0:38ceb79fef03 372 size_t n;
kevman 0:38ceb79fef03 373 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
kevman 0:38ceb79fef03 374
kevman 0:38ceb79fef03 375 if( ( f = fopen( path, "rb" ) ) == NULL )
kevman 0:38ceb79fef03 376 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
kevman 0:38ceb79fef03 377
kevman 0:38ceb79fef03 378 fseek( f, 0, SEEK_END );
kevman 0:38ceb79fef03 379 n = (size_t) ftell( f );
kevman 0:38ceb79fef03 380 fseek( f, 0, SEEK_SET );
kevman 0:38ceb79fef03 381
kevman 0:38ceb79fef03 382 if( n > MBEDTLS_HMAC_DRBG_MAX_INPUT )
kevman 0:38ceb79fef03 383 {
kevman 0:38ceb79fef03 384 fclose( f );
kevman 0:38ceb79fef03 385 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
kevman 0:38ceb79fef03 386 }
kevman 0:38ceb79fef03 387
kevman 0:38ceb79fef03 388 if( fread( buf, 1, n, f ) != n )
kevman 0:38ceb79fef03 389 ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
kevman 0:38ceb79fef03 390 else
kevman 0:38ceb79fef03 391 mbedtls_hmac_drbg_update( ctx, buf, n );
kevman 0:38ceb79fef03 392
kevman 0:38ceb79fef03 393 fclose( f );
kevman 0:38ceb79fef03 394
kevman 0:38ceb79fef03 395 mbedtls_platform_zeroize( buf, sizeof( buf ) );
kevman 0:38ceb79fef03 396
kevman 0:38ceb79fef03 397 if( ret != 0 )
kevman 0:38ceb79fef03 398 return( ret );
kevman 0:38ceb79fef03 399
kevman 0:38ceb79fef03 400 return( mbedtls_hmac_drbg_write_seed_file( ctx, path ) );
kevman 0:38ceb79fef03 401 }
kevman 0:38ceb79fef03 402 #endif /* MBEDTLS_FS_IO */
kevman 0:38ceb79fef03 403
kevman 0:38ceb79fef03 404
kevman 0:38ceb79fef03 405 #if defined(MBEDTLS_SELF_TEST)
kevman 0:38ceb79fef03 406
kevman 0:38ceb79fef03 407 #if !defined(MBEDTLS_SHA1_C)
kevman 0:38ceb79fef03 408 /* Dummy checkup routine */
kevman 0:38ceb79fef03 409 int mbedtls_hmac_drbg_self_test( int verbose )
kevman 0:38ceb79fef03 410 {
kevman 0:38ceb79fef03 411 (void) verbose;
kevman 0:38ceb79fef03 412 return( 0 );
kevman 0:38ceb79fef03 413 }
kevman 0:38ceb79fef03 414 #else
kevman 0:38ceb79fef03 415
kevman 0:38ceb79fef03 416 #define OUTPUT_LEN 80
kevman 0:38ceb79fef03 417
kevman 0:38ceb79fef03 418 /* From a NIST PR=true test vector */
kevman 0:38ceb79fef03 419 static const unsigned char entropy_pr[] = {
kevman 0:38ceb79fef03 420 0xa0, 0xc9, 0xab, 0x58, 0xf1, 0xe2, 0xe5, 0xa4, 0xde, 0x3e, 0xbd, 0x4f,
kevman 0:38ceb79fef03 421 0xf7, 0x3e, 0x9c, 0x5b, 0x64, 0xef, 0xd8, 0xca, 0x02, 0x8c, 0xf8, 0x11,
kevman 0:38ceb79fef03 422 0x48, 0xa5, 0x84, 0xfe, 0x69, 0xab, 0x5a, 0xee, 0x42, 0xaa, 0x4d, 0x42,
kevman 0:38ceb79fef03 423 0x17, 0x60, 0x99, 0xd4, 0x5e, 0x13, 0x97, 0xdc, 0x40, 0x4d, 0x86, 0xa3,
kevman 0:38ceb79fef03 424 0x7b, 0xf5, 0x59, 0x54, 0x75, 0x69, 0x51, 0xe4 };
kevman 0:38ceb79fef03 425 static const unsigned char result_pr[OUTPUT_LEN] = {
kevman 0:38ceb79fef03 426 0x9a, 0x00, 0xa2, 0xd0, 0x0e, 0xd5, 0x9b, 0xfe, 0x31, 0xec, 0xb1, 0x39,
kevman 0:38ceb79fef03 427 0x9b, 0x60, 0x81, 0x48, 0xd1, 0x96, 0x9d, 0x25, 0x0d, 0x3c, 0x1e, 0x94,
kevman 0:38ceb79fef03 428 0x10, 0x10, 0x98, 0x12, 0x93, 0x25, 0xca, 0xb8, 0xfc, 0xcc, 0x2d, 0x54,
kevman 0:38ceb79fef03 429 0x73, 0x19, 0x70, 0xc0, 0x10, 0x7a, 0xa4, 0x89, 0x25, 0x19, 0x95, 0x5e,
kevman 0:38ceb79fef03 430 0x4b, 0xc6, 0x00, 0x1d, 0x7f, 0x4e, 0x6a, 0x2b, 0xf8, 0xa3, 0x01, 0xab,
kevman 0:38ceb79fef03 431 0x46, 0x05, 0x5c, 0x09, 0xa6, 0x71, 0x88, 0xf1, 0xa7, 0x40, 0xee, 0xf3,
kevman 0:38ceb79fef03 432 0xe1, 0x5c, 0x02, 0x9b, 0x44, 0xaf, 0x03, 0x44 };
kevman 0:38ceb79fef03 433
kevman 0:38ceb79fef03 434 /* From a NIST PR=false test vector */
kevman 0:38ceb79fef03 435 static const unsigned char entropy_nopr[] = {
kevman 0:38ceb79fef03 436 0x79, 0x34, 0x9b, 0xbf, 0x7c, 0xdd, 0xa5, 0x79, 0x95, 0x57, 0x86, 0x66,
kevman 0:38ceb79fef03 437 0x21, 0xc9, 0x13, 0x83, 0x11, 0x46, 0x73, 0x3a, 0xbf, 0x8c, 0x35, 0xc8,
kevman 0:38ceb79fef03 438 0xc7, 0x21, 0x5b, 0x5b, 0x96, 0xc4, 0x8e, 0x9b, 0x33, 0x8c, 0x74, 0xe3,
kevman 0:38ceb79fef03 439 0xe9, 0x9d, 0xfe, 0xdf };
kevman 0:38ceb79fef03 440 static const unsigned char result_nopr[OUTPUT_LEN] = {
kevman 0:38ceb79fef03 441 0xc6, 0xa1, 0x6a, 0xb8, 0xd4, 0x20, 0x70, 0x6f, 0x0f, 0x34, 0xab, 0x7f,
kevman 0:38ceb79fef03 442 0xec, 0x5a, 0xdc, 0xa9, 0xd8, 0xca, 0x3a, 0x13, 0x3e, 0x15, 0x9c, 0xa6,
kevman 0:38ceb79fef03 443 0xac, 0x43, 0xc6, 0xf8, 0xa2, 0xbe, 0x22, 0x83, 0x4a, 0x4c, 0x0a, 0x0a,
kevman 0:38ceb79fef03 444 0xff, 0xb1, 0x0d, 0x71, 0x94, 0xf1, 0xc1, 0xa5, 0xcf, 0x73, 0x22, 0xec,
kevman 0:38ceb79fef03 445 0x1a, 0xe0, 0x96, 0x4e, 0xd4, 0xbf, 0x12, 0x27, 0x46, 0xe0, 0x87, 0xfd,
kevman 0:38ceb79fef03 446 0xb5, 0xb3, 0xe9, 0x1b, 0x34, 0x93, 0xd5, 0xbb, 0x98, 0xfa, 0xed, 0x49,
kevman 0:38ceb79fef03 447 0xe8, 0x5f, 0x13, 0x0f, 0xc8, 0xa4, 0x59, 0xb7 };
kevman 0:38ceb79fef03 448
kevman 0:38ceb79fef03 449 /* "Entropy" from buffer */
kevman 0:38ceb79fef03 450 static size_t test_offset;
kevman 0:38ceb79fef03 451 static int hmac_drbg_self_test_entropy( void *data,
kevman 0:38ceb79fef03 452 unsigned char *buf, size_t len )
kevman 0:38ceb79fef03 453 {
kevman 0:38ceb79fef03 454 const unsigned char *p = data;
kevman 0:38ceb79fef03 455 memcpy( buf, p + test_offset, len );
kevman 0:38ceb79fef03 456 test_offset += len;
kevman 0:38ceb79fef03 457 return( 0 );
kevman 0:38ceb79fef03 458 }
kevman 0:38ceb79fef03 459
kevman 0:38ceb79fef03 460 #define CHK( c ) if( (c) != 0 ) \
kevman 0:38ceb79fef03 461 { \
kevman 0:38ceb79fef03 462 if( verbose != 0 ) \
kevman 0:38ceb79fef03 463 mbedtls_printf( "failed\n" ); \
kevman 0:38ceb79fef03 464 return( 1 ); \
kevman 0:38ceb79fef03 465 }
kevman 0:38ceb79fef03 466
kevman 0:38ceb79fef03 467 /*
kevman 0:38ceb79fef03 468 * Checkup routine for HMAC_DRBG with SHA-1
kevman 0:38ceb79fef03 469 */
kevman 0:38ceb79fef03 470 int mbedtls_hmac_drbg_self_test( int verbose )
kevman 0:38ceb79fef03 471 {
kevman 0:38ceb79fef03 472 mbedtls_hmac_drbg_context ctx;
kevman 0:38ceb79fef03 473 unsigned char buf[OUTPUT_LEN];
kevman 0:38ceb79fef03 474 const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
kevman 0:38ceb79fef03 475
kevman 0:38ceb79fef03 476 mbedtls_hmac_drbg_init( &ctx );
kevman 0:38ceb79fef03 477
kevman 0:38ceb79fef03 478 /*
kevman 0:38ceb79fef03 479 * PR = True
kevman 0:38ceb79fef03 480 */
kevman 0:38ceb79fef03 481 if( verbose != 0 )
kevman 0:38ceb79fef03 482 mbedtls_printf( " HMAC_DRBG (PR = True) : " );
kevman 0:38ceb79fef03 483
kevman 0:38ceb79fef03 484 test_offset = 0;
kevman 0:38ceb79fef03 485 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
kevman 0:38ceb79fef03 486 hmac_drbg_self_test_entropy, (void *) entropy_pr,
kevman 0:38ceb79fef03 487 NULL, 0 ) );
kevman 0:38ceb79fef03 488 mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
kevman 0:38ceb79fef03 489 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
kevman 0:38ceb79fef03 490 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
kevman 0:38ceb79fef03 491 CHK( memcmp( buf, result_pr, OUTPUT_LEN ) );
kevman 0:38ceb79fef03 492 mbedtls_hmac_drbg_free( &ctx );
kevman 0:38ceb79fef03 493
kevman 0:38ceb79fef03 494 mbedtls_hmac_drbg_free( &ctx );
kevman 0:38ceb79fef03 495
kevman 0:38ceb79fef03 496 if( verbose != 0 )
kevman 0:38ceb79fef03 497 mbedtls_printf( "passed\n" );
kevman 0:38ceb79fef03 498
kevman 0:38ceb79fef03 499 /*
kevman 0:38ceb79fef03 500 * PR = False
kevman 0:38ceb79fef03 501 */
kevman 0:38ceb79fef03 502 if( verbose != 0 )
kevman 0:38ceb79fef03 503 mbedtls_printf( " HMAC_DRBG (PR = False) : " );
kevman 0:38ceb79fef03 504
kevman 0:38ceb79fef03 505 mbedtls_hmac_drbg_init( &ctx );
kevman 0:38ceb79fef03 506
kevman 0:38ceb79fef03 507 test_offset = 0;
kevman 0:38ceb79fef03 508 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
kevman 0:38ceb79fef03 509 hmac_drbg_self_test_entropy, (void *) entropy_nopr,
kevman 0:38ceb79fef03 510 NULL, 0 ) );
kevman 0:38ceb79fef03 511 CHK( mbedtls_hmac_drbg_reseed( &ctx, NULL, 0 ) );
kevman 0:38ceb79fef03 512 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
kevman 0:38ceb79fef03 513 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
kevman 0:38ceb79fef03 514 CHK( memcmp( buf, result_nopr, OUTPUT_LEN ) );
kevman 0:38ceb79fef03 515 mbedtls_hmac_drbg_free( &ctx );
kevman 0:38ceb79fef03 516
kevman 0:38ceb79fef03 517 mbedtls_hmac_drbg_free( &ctx );
kevman 0:38ceb79fef03 518
kevman 0:38ceb79fef03 519 if( verbose != 0 )
kevman 0:38ceb79fef03 520 mbedtls_printf( "passed\n" );
kevman 0:38ceb79fef03 521
kevman 0:38ceb79fef03 522 if( verbose != 0 )
kevman 0:38ceb79fef03 523 mbedtls_printf( "\n" );
kevman 0:38ceb79fef03 524
kevman 0:38ceb79fef03 525 return( 0 );
kevman 0:38ceb79fef03 526 }
kevman 0:38ceb79fef03 527 #endif /* MBEDTLS_SHA1_C */
kevman 0:38ceb79fef03 528 #endif /* MBEDTLS_SELF_TEST */
kevman 0:38ceb79fef03 529
kevman 0:38ceb79fef03 530 #endif /* MBEDTLS_HMAC_DRBG_C */