Mark Radbourne / mbedtls

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library/hmac_drbg.c@0:cdf462088d13, 2017-01-05 (annotated)

Committer:
markrad
Date:
Thu Jan 05 00:18:44 2017 +0000
Revision:
0:cdf462088d13
Initial commit

Who changed what in which revision?

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markrad 0:cdf462088d13 1 /*
markrad 0:cdf462088d13 2 * HMAC_DRBG implementation (NIST SP 800-90)
markrad 0:cdf462088d13 3 *
markrad 0:cdf462088d13 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
markrad 0:cdf462088d13 5 * SPDX-License-Identifier: Apache-2.0
markrad 0:cdf462088d13 6 *
markrad 0:cdf462088d13 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
markrad 0:cdf462088d13 8 * not use this file except in compliance with the License.
markrad 0:cdf462088d13 9 * You may obtain a copy of the License at
markrad 0:cdf462088d13 10 *
markrad 0:cdf462088d13 11 * http://www.apache.org/licenses/LICENSE-2.0
markrad 0:cdf462088d13 12 *
markrad 0:cdf462088d13 13 * Unless required by applicable law or agreed to in writing, software
markrad 0:cdf462088d13 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
markrad 0:cdf462088d13 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
markrad 0:cdf462088d13 16 * See the License for the specific language governing permissions and
markrad 0:cdf462088d13 17 * limitations under the License.
markrad 0:cdf462088d13 18 *
markrad 0:cdf462088d13 19 * This file is part of mbed TLS (https://tls.mbed.org)
markrad 0:cdf462088d13 20 */
markrad 0:cdf462088d13 21
markrad 0:cdf462088d13 22 /*
markrad 0:cdf462088d13 23 * The NIST SP 800-90A DRBGs are described in the following publication.
markrad 0:cdf462088d13 24 * http://csrc.nist.gov/publications/nistpubs/800-90A/SP800-90A.pdf
markrad 0:cdf462088d13 25 * References below are based on rev. 1 (January 2012).
markrad 0:cdf462088d13 26 */
markrad 0:cdf462088d13 27
markrad 0:cdf462088d13 28 #if !defined(MBEDTLS_CONFIG_FILE)
markrad 0:cdf462088d13 29 #include "mbedtls/config.h"
markrad 0:cdf462088d13 30 #else
markrad 0:cdf462088d13 31 #include MBEDTLS_CONFIG_FILE
markrad 0:cdf462088d13 32 #endif
markrad 0:cdf462088d13 33
markrad 0:cdf462088d13 34 #if defined(MBEDTLS_HMAC_DRBG_C)
markrad 0:cdf462088d13 35
markrad 0:cdf462088d13 36 #include "mbedtls/hmac_drbg.h"
markrad 0:cdf462088d13 37
markrad 0:cdf462088d13 38 #include <string.h>
markrad 0:cdf462088d13 39
markrad 0:cdf462088d13 40 #if defined(MBEDTLS_FS_IO)
markrad 0:cdf462088d13 41 #include <stdio.h>
markrad 0:cdf462088d13 42 #endif
markrad 0:cdf462088d13 43
markrad 0:cdf462088d13 44 #if defined(MBEDTLS_SELF_TEST)
markrad 0:cdf462088d13 45 #if defined(MBEDTLS_PLATFORM_C)
markrad 0:cdf462088d13 46 #include "mbedtls/platform.h"
markrad 0:cdf462088d13 47 #else
markrad 0:cdf462088d13 48 #include <stdio.h>
markrad 0:cdf462088d13 49 #define mbedtls_printf printf
markrad 0:cdf462088d13 50 #endif /* MBEDTLS_SELF_TEST */
markrad 0:cdf462088d13 51 #endif /* MBEDTLS_PLATFORM_C */
markrad 0:cdf462088d13 52
markrad 0:cdf462088d13 53 /* Implementation that should never be optimized out by the compiler */
markrad 0:cdf462088d13 54 static void mbedtls_zeroize( void *v, size_t n ) {
markrad 0:cdf462088d13 55 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
markrad 0:cdf462088d13 56 }
markrad 0:cdf462088d13 57
markrad 0:cdf462088d13 58 /*
markrad 0:cdf462088d13 59 * HMAC_DRBG context initialization
markrad 0:cdf462088d13 60 */
markrad 0:cdf462088d13 61 void mbedtls_hmac_drbg_init( mbedtls_hmac_drbg_context *ctx )
markrad 0:cdf462088d13 62 {
markrad 0:cdf462088d13 63 memset( ctx, 0, sizeof( mbedtls_hmac_drbg_context ) );
markrad 0:cdf462088d13 64
markrad 0:cdf462088d13 65 #if defined(MBEDTLS_THREADING_C)
markrad 0:cdf462088d13 66 mbedtls_mutex_init( &ctx->mutex );
markrad 0:cdf462088d13 67 #endif
markrad 0:cdf462088d13 68 }
markrad 0:cdf462088d13 69
markrad 0:cdf462088d13 70 /*
markrad 0:cdf462088d13 71 * HMAC_DRBG update, using optional additional data (10.1.2.2)
markrad 0:cdf462088d13 72 */
markrad 0:cdf462088d13 73 void mbedtls_hmac_drbg_update( mbedtls_hmac_drbg_context *ctx,
markrad 0:cdf462088d13 74 const unsigned char *additional, size_t add_len )
markrad 0:cdf462088d13 75 {
markrad 0:cdf462088d13 76 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
markrad 0:cdf462088d13 77 unsigned char rounds = ( additional != NULL && add_len != 0 ) ? 2 : 1;
markrad 0:cdf462088d13 78 unsigned char sep[1];
markrad 0:cdf462088d13 79 unsigned char K[MBEDTLS_MD_MAX_SIZE];
markrad 0:cdf462088d13 80
markrad 0:cdf462088d13 81 for( sep[0] = 0; sep[0] < rounds; sep[0]++ )
markrad 0:cdf462088d13 82 {
markrad 0:cdf462088d13 83 /* Step 1 or 4 */
markrad 0:cdf462088d13 84 mbedtls_md_hmac_reset( &ctx->md_ctx );
markrad 0:cdf462088d13 85 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
markrad 0:cdf462088d13 86 mbedtls_md_hmac_update( &ctx->md_ctx, sep, 1 );
markrad 0:cdf462088d13 87 if( rounds == 2 )
markrad 0:cdf462088d13 88 mbedtls_md_hmac_update( &ctx->md_ctx, additional, add_len );
markrad 0:cdf462088d13 89 mbedtls_md_hmac_finish( &ctx->md_ctx, K );
markrad 0:cdf462088d13 90
markrad 0:cdf462088d13 91 /* Step 2 or 5 */
markrad 0:cdf462088d13 92 mbedtls_md_hmac_starts( &ctx->md_ctx, K, md_len );
markrad 0:cdf462088d13 93 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
markrad 0:cdf462088d13 94 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
markrad 0:cdf462088d13 95 }
markrad 0:cdf462088d13 96 }
markrad 0:cdf462088d13 97
markrad 0:cdf462088d13 98 /*
markrad 0:cdf462088d13 99 * Simplified HMAC_DRBG initialisation (for use with deterministic ECDSA)
markrad 0:cdf462088d13 100 */
markrad 0:cdf462088d13 101 int mbedtls_hmac_drbg_seed_buf( mbedtls_hmac_drbg_context *ctx,
markrad 0:cdf462088d13 102 const mbedtls_md_info_t * md_info,
markrad 0:cdf462088d13 103 const unsigned char *data, size_t data_len )
markrad 0:cdf462088d13 104 {
markrad 0:cdf462088d13 105 int ret;
markrad 0:cdf462088d13 106
markrad 0:cdf462088d13 107 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
markrad 0:cdf462088d13 108 return( ret );
markrad 0:cdf462088d13 109
markrad 0:cdf462088d13 110 /*
markrad 0:cdf462088d13 111 * Set initial working state.
markrad 0:cdf462088d13 112 * Use the V memory location, which is currently all 0, to initialize the
markrad 0:cdf462088d13 113 * MD context with an all-zero key. Then set V to its initial value.
markrad 0:cdf462088d13 114 */
markrad 0:cdf462088d13 115 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, mbedtls_md_get_size( md_info ) );
markrad 0:cdf462088d13 116 memset( ctx->V, 0x01, mbedtls_md_get_size( md_info ) );
markrad 0:cdf462088d13 117
markrad 0:cdf462088d13 118 mbedtls_hmac_drbg_update( ctx, data, data_len );
markrad 0:cdf462088d13 119
markrad 0:cdf462088d13 120 return( 0 );
markrad 0:cdf462088d13 121 }
markrad 0:cdf462088d13 122
markrad 0:cdf462088d13 123 /*
markrad 0:cdf462088d13 124 * HMAC_DRBG reseeding: 10.1.2.4 (arabic) + 9.2 (Roman)
markrad 0:cdf462088d13 125 */
markrad 0:cdf462088d13 126 int mbedtls_hmac_drbg_reseed( mbedtls_hmac_drbg_context *ctx,
markrad 0:cdf462088d13 127 const unsigned char *additional, size_t len )
markrad 0:cdf462088d13 128 {
markrad 0:cdf462088d13 129 unsigned char seed[MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT];
markrad 0:cdf462088d13 130 size_t seedlen;
markrad 0:cdf462088d13 131
markrad 0:cdf462088d13 132 /* III. Check input length */
markrad 0:cdf462088d13 133 if( len > MBEDTLS_HMAC_DRBG_MAX_INPUT ||
markrad 0:cdf462088d13 134 ctx->entropy_len + len > MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT )
markrad 0:cdf462088d13 135 {
markrad 0:cdf462088d13 136 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
markrad 0:cdf462088d13 137 }
markrad 0:cdf462088d13 138
markrad 0:cdf462088d13 139 memset( seed, 0, MBEDTLS_HMAC_DRBG_MAX_SEED_INPUT );
markrad 0:cdf462088d13 140
markrad 0:cdf462088d13 141 /* IV. Gather entropy_len bytes of entropy for the seed */
markrad 0:cdf462088d13 142 if( ctx->f_entropy( ctx->p_entropy, seed, ctx->entropy_len ) != 0 )
markrad 0:cdf462088d13 143 return( MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED );
markrad 0:cdf462088d13 144
markrad 0:cdf462088d13 145 seedlen = ctx->entropy_len;
markrad 0:cdf462088d13 146
markrad 0:cdf462088d13 147 /* 1. Concatenate entropy and additional data if any */
markrad 0:cdf462088d13 148 if( additional != NULL && len != 0 )
markrad 0:cdf462088d13 149 {
markrad 0:cdf462088d13 150 memcpy( seed + seedlen, additional, len );
markrad 0:cdf462088d13 151 seedlen += len;
markrad 0:cdf462088d13 152 }
markrad 0:cdf462088d13 153
markrad 0:cdf462088d13 154 /* 2. Update state */
markrad 0:cdf462088d13 155 mbedtls_hmac_drbg_update( ctx, seed, seedlen );
markrad 0:cdf462088d13 156
markrad 0:cdf462088d13 157 /* 3. Reset reseed_counter */
markrad 0:cdf462088d13 158 ctx->reseed_counter = 1;
markrad 0:cdf462088d13 159
markrad 0:cdf462088d13 160 /* 4. Done */
markrad 0:cdf462088d13 161 return( 0 );
markrad 0:cdf462088d13 162 }
markrad 0:cdf462088d13 163
markrad 0:cdf462088d13 164 /*
markrad 0:cdf462088d13 165 * HMAC_DRBG initialisation (10.1.2.3 + 9.1)
markrad 0:cdf462088d13 166 */
markrad 0:cdf462088d13 167 int mbedtls_hmac_drbg_seed( mbedtls_hmac_drbg_context *ctx,
markrad 0:cdf462088d13 168 const mbedtls_md_info_t * md_info,
markrad 0:cdf462088d13 169 int (*f_entropy)(void *, unsigned char *, size_t),
markrad 0:cdf462088d13 170 void *p_entropy,
markrad 0:cdf462088d13 171 const unsigned char *custom,
markrad 0:cdf462088d13 172 size_t len )
markrad 0:cdf462088d13 173 {
markrad 0:cdf462088d13 174 int ret;
markrad 0:cdf462088d13 175 size_t entropy_len, md_size;
markrad 0:cdf462088d13 176
markrad 0:cdf462088d13 177 if( ( ret = mbedtls_md_setup( &ctx->md_ctx, md_info, 1 ) ) != 0 )
markrad 0:cdf462088d13 178 return( ret );
markrad 0:cdf462088d13 179
markrad 0:cdf462088d13 180 md_size = mbedtls_md_get_size( md_info );
markrad 0:cdf462088d13 181
markrad 0:cdf462088d13 182 /*
markrad 0:cdf462088d13 183 * Set initial working state.
markrad 0:cdf462088d13 184 * Use the V memory location, which is currently all 0, to initialize the
markrad 0:cdf462088d13 185 * MD context with an all-zero key. Then set V to its initial value.
markrad 0:cdf462088d13 186 */
markrad 0:cdf462088d13 187 mbedtls_md_hmac_starts( &ctx->md_ctx, ctx->V, md_size );
markrad 0:cdf462088d13 188 memset( ctx->V, 0x01, md_size );
markrad 0:cdf462088d13 189
markrad 0:cdf462088d13 190 ctx->f_entropy = f_entropy;
markrad 0:cdf462088d13 191 ctx->p_entropy = p_entropy;
markrad 0:cdf462088d13 192
markrad 0:cdf462088d13 193 ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL;
markrad 0:cdf462088d13 194
markrad 0:cdf462088d13 195 /*
markrad 0:cdf462088d13 196 * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by
markrad 0:cdf462088d13 197 * each hash function, then according to SP800-90A rev1 10.1 table 2,
markrad 0:cdf462088d13 198 * min_entropy_len (in bits) is security_strength.
markrad 0:cdf462088d13 199 *
markrad 0:cdf462088d13 200 * (This also matches the sizes used in the NIST test vectors.)
markrad 0:cdf462088d13 201 */
markrad 0:cdf462088d13 202 entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */
markrad 0:cdf462088d13 203 md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */
markrad 0:cdf462088d13 204 32; /* better (256+) -> 256 bits */
markrad 0:cdf462088d13 205
markrad 0:cdf462088d13 206 /*
markrad 0:cdf462088d13 207 * For initialisation, use more entropy to emulate a nonce
markrad 0:cdf462088d13 208 * (Again, matches test vectors.)
markrad 0:cdf462088d13 209 */
markrad 0:cdf462088d13 210 ctx->entropy_len = entropy_len * 3 / 2;
markrad 0:cdf462088d13 211
markrad 0:cdf462088d13 212 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, custom, len ) ) != 0 )
markrad 0:cdf462088d13 213 return( ret );
markrad 0:cdf462088d13 214
markrad 0:cdf462088d13 215 ctx->entropy_len = entropy_len;
markrad 0:cdf462088d13 216
markrad 0:cdf462088d13 217 return( 0 );
markrad 0:cdf462088d13 218 }
markrad 0:cdf462088d13 219
markrad 0:cdf462088d13 220 /*
markrad 0:cdf462088d13 221 * Set prediction resistance
markrad 0:cdf462088d13 222 */
markrad 0:cdf462088d13 223 void mbedtls_hmac_drbg_set_prediction_resistance( mbedtls_hmac_drbg_context *ctx,
markrad 0:cdf462088d13 224 int resistance )
markrad 0:cdf462088d13 225 {
markrad 0:cdf462088d13 226 ctx->prediction_resistance = resistance;
markrad 0:cdf462088d13 227 }
markrad 0:cdf462088d13 228
markrad 0:cdf462088d13 229 /*
markrad 0:cdf462088d13 230 * Set entropy length grabbed for reseeds
markrad 0:cdf462088d13 231 */
markrad 0:cdf462088d13 232 void mbedtls_hmac_drbg_set_entropy_len( mbedtls_hmac_drbg_context *ctx, size_t len )
markrad 0:cdf462088d13 233 {
markrad 0:cdf462088d13 234 ctx->entropy_len = len;
markrad 0:cdf462088d13 235 }
markrad 0:cdf462088d13 236
markrad 0:cdf462088d13 237 /*
markrad 0:cdf462088d13 238 * Set reseed interval
markrad 0:cdf462088d13 239 */
markrad 0:cdf462088d13 240 void mbedtls_hmac_drbg_set_reseed_interval( mbedtls_hmac_drbg_context *ctx, int interval )
markrad 0:cdf462088d13 241 {
markrad 0:cdf462088d13 242 ctx->reseed_interval = interval;
markrad 0:cdf462088d13 243 }
markrad 0:cdf462088d13 244
markrad 0:cdf462088d13 245 /*
markrad 0:cdf462088d13 246 * HMAC_DRBG random function with optional additional data:
markrad 0:cdf462088d13 247 * 10.1.2.5 (arabic) + 9.3 (Roman)
markrad 0:cdf462088d13 248 */
markrad 0:cdf462088d13 249 int mbedtls_hmac_drbg_random_with_add( void *p_rng,
markrad 0:cdf462088d13 250 unsigned char *output, size_t out_len,
markrad 0:cdf462088d13 251 const unsigned char *additional, size_t add_len )
markrad 0:cdf462088d13 252 {
markrad 0:cdf462088d13 253 int ret;
markrad 0:cdf462088d13 254 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
markrad 0:cdf462088d13 255 size_t md_len = mbedtls_md_get_size( ctx->md_ctx.md_info );
markrad 0:cdf462088d13 256 size_t left = out_len;
markrad 0:cdf462088d13 257 unsigned char *out = output;
markrad 0:cdf462088d13 258
markrad 0:cdf462088d13 259 /* II. Check request length */
markrad 0:cdf462088d13 260 if( out_len > MBEDTLS_HMAC_DRBG_MAX_REQUEST )
markrad 0:cdf462088d13 261 return( MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG );
markrad 0:cdf462088d13 262
markrad 0:cdf462088d13 263 /* III. Check input length */
markrad 0:cdf462088d13 264 if( add_len > MBEDTLS_HMAC_DRBG_MAX_INPUT )
markrad 0:cdf462088d13 265 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
markrad 0:cdf462088d13 266
markrad 0:cdf462088d13 267 /* 1. (aka VII and IX) Check reseed counter and PR */
markrad 0:cdf462088d13 268 if( ctx->f_entropy != NULL && /* For no-reseeding instances */
markrad 0:cdf462088d13 269 ( ctx->prediction_resistance == MBEDTLS_HMAC_DRBG_PR_ON ||
markrad 0:cdf462088d13 270 ctx->reseed_counter > ctx->reseed_interval ) )
markrad 0:cdf462088d13 271 {
markrad 0:cdf462088d13 272 if( ( ret = mbedtls_hmac_drbg_reseed( ctx, additional, add_len ) ) != 0 )
markrad 0:cdf462088d13 273 return( ret );
markrad 0:cdf462088d13 274
markrad 0:cdf462088d13 275 add_len = 0; /* VII.4 */
markrad 0:cdf462088d13 276 }
markrad 0:cdf462088d13 277
markrad 0:cdf462088d13 278 /* 2. Use additional data if any */
markrad 0:cdf462088d13 279 if( additional != NULL && add_len != 0 )
markrad 0:cdf462088d13 280 mbedtls_hmac_drbg_update( ctx, additional, add_len );
markrad 0:cdf462088d13 281
markrad 0:cdf462088d13 282 /* 3, 4, 5. Generate bytes */
markrad 0:cdf462088d13 283 while( left != 0 )
markrad 0:cdf462088d13 284 {
markrad 0:cdf462088d13 285 size_t use_len = left > md_len ? md_len : left;
markrad 0:cdf462088d13 286
markrad 0:cdf462088d13 287 mbedtls_md_hmac_reset( &ctx->md_ctx );
markrad 0:cdf462088d13 288 mbedtls_md_hmac_update( &ctx->md_ctx, ctx->V, md_len );
markrad 0:cdf462088d13 289 mbedtls_md_hmac_finish( &ctx->md_ctx, ctx->V );
markrad 0:cdf462088d13 290
markrad 0:cdf462088d13 291 memcpy( out, ctx->V, use_len );
markrad 0:cdf462088d13 292 out += use_len;
markrad 0:cdf462088d13 293 left -= use_len;
markrad 0:cdf462088d13 294 }
markrad 0:cdf462088d13 295
markrad 0:cdf462088d13 296 /* 6. Update */
markrad 0:cdf462088d13 297 mbedtls_hmac_drbg_update( ctx, additional, add_len );
markrad 0:cdf462088d13 298
markrad 0:cdf462088d13 299 /* 7. Update reseed counter */
markrad 0:cdf462088d13 300 ctx->reseed_counter++;
markrad 0:cdf462088d13 301
markrad 0:cdf462088d13 302 /* 8. Done */
markrad 0:cdf462088d13 303 return( 0 );
markrad 0:cdf462088d13 304 }
markrad 0:cdf462088d13 305
markrad 0:cdf462088d13 306 /*
markrad 0:cdf462088d13 307 * HMAC_DRBG random function
markrad 0:cdf462088d13 308 */
markrad 0:cdf462088d13 309 int mbedtls_hmac_drbg_random( void *p_rng, unsigned char *output, size_t out_len )
markrad 0:cdf462088d13 310 {
markrad 0:cdf462088d13 311 int ret;
markrad 0:cdf462088d13 312 mbedtls_hmac_drbg_context *ctx = (mbedtls_hmac_drbg_context *) p_rng;
markrad 0:cdf462088d13 313
markrad 0:cdf462088d13 314 #if defined(MBEDTLS_THREADING_C)
markrad 0:cdf462088d13 315 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
markrad 0:cdf462088d13 316 return( ret );
markrad 0:cdf462088d13 317 #endif
markrad 0:cdf462088d13 318
markrad 0:cdf462088d13 319 ret = mbedtls_hmac_drbg_random_with_add( ctx, output, out_len, NULL, 0 );
markrad 0:cdf462088d13 320
markrad 0:cdf462088d13 321 #if defined(MBEDTLS_THREADING_C)
markrad 0:cdf462088d13 322 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
markrad 0:cdf462088d13 323 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
markrad 0:cdf462088d13 324 #endif
markrad 0:cdf462088d13 325
markrad 0:cdf462088d13 326 return( ret );
markrad 0:cdf462088d13 327 }
markrad 0:cdf462088d13 328
markrad 0:cdf462088d13 329 /*
markrad 0:cdf462088d13 330 * Free an HMAC_DRBG context
markrad 0:cdf462088d13 331 */
markrad 0:cdf462088d13 332 void mbedtls_hmac_drbg_free( mbedtls_hmac_drbg_context *ctx )
markrad 0:cdf462088d13 333 {
markrad 0:cdf462088d13 334 if( ctx == NULL )
markrad 0:cdf462088d13 335 return;
markrad 0:cdf462088d13 336
markrad 0:cdf462088d13 337 #if defined(MBEDTLS_THREADING_C)
markrad 0:cdf462088d13 338 mbedtls_mutex_free( &ctx->mutex );
markrad 0:cdf462088d13 339 #endif
markrad 0:cdf462088d13 340 mbedtls_md_free( &ctx->md_ctx );
markrad 0:cdf462088d13 341 mbedtls_zeroize( ctx, sizeof( mbedtls_hmac_drbg_context ) );
markrad 0:cdf462088d13 342 }
markrad 0:cdf462088d13 343
markrad 0:cdf462088d13 344 #if defined(MBEDTLS_FS_IO)
markrad 0:cdf462088d13 345 int mbedtls_hmac_drbg_write_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
markrad 0:cdf462088d13 346 {
markrad 0:cdf462088d13 347 int ret;
markrad 0:cdf462088d13 348 FILE *f;
markrad 0:cdf462088d13 349 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
markrad 0:cdf462088d13 350
markrad 0:cdf462088d13 351 if( ( f = fopen( path, "wb" ) ) == NULL )
markrad 0:cdf462088d13 352 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
markrad 0:cdf462088d13 353
markrad 0:cdf462088d13 354 if( ( ret = mbedtls_hmac_drbg_random( ctx, buf, sizeof( buf ) ) ) != 0 )
markrad 0:cdf462088d13 355 goto exit;
markrad 0:cdf462088d13 356
markrad 0:cdf462088d13 357 if( fwrite( buf, 1, sizeof( buf ), f ) != sizeof( buf ) )
markrad 0:cdf462088d13 358 {
markrad 0:cdf462088d13 359 ret = MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR;
markrad 0:cdf462088d13 360 goto exit;
markrad 0:cdf462088d13 361 }
markrad 0:cdf462088d13 362
markrad 0:cdf462088d13 363 ret = 0;
markrad 0:cdf462088d13 364
markrad 0:cdf462088d13 365 exit:
markrad 0:cdf462088d13 366 fclose( f );
markrad 0:cdf462088d13 367 return( ret );
markrad 0:cdf462088d13 368 }
markrad 0:cdf462088d13 369
markrad 0:cdf462088d13 370 int mbedtls_hmac_drbg_update_seed_file( mbedtls_hmac_drbg_context *ctx, const char *path )
markrad 0:cdf462088d13 371 {
markrad 0:cdf462088d13 372 FILE *f;
markrad 0:cdf462088d13 373 size_t n;
markrad 0:cdf462088d13 374 unsigned char buf[ MBEDTLS_HMAC_DRBG_MAX_INPUT ];
markrad 0:cdf462088d13 375
markrad 0:cdf462088d13 376 if( ( f = fopen( path, "rb" ) ) == NULL )
markrad 0:cdf462088d13 377 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
markrad 0:cdf462088d13 378
markrad 0:cdf462088d13 379 fseek( f, 0, SEEK_END );
markrad 0:cdf462088d13 380 n = (size_t) ftell( f );
markrad 0:cdf462088d13 381 fseek( f, 0, SEEK_SET );
markrad 0:cdf462088d13 382
markrad 0:cdf462088d13 383 if( n > MBEDTLS_HMAC_DRBG_MAX_INPUT )
markrad 0:cdf462088d13 384 {
markrad 0:cdf462088d13 385 fclose( f );
markrad 0:cdf462088d13 386 return( MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG );
markrad 0:cdf462088d13 387 }
markrad 0:cdf462088d13 388
markrad 0:cdf462088d13 389 if( fread( buf, 1, n, f ) != n )
markrad 0:cdf462088d13 390 {
markrad 0:cdf462088d13 391 fclose( f );
markrad 0:cdf462088d13 392 return( MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR );
markrad 0:cdf462088d13 393 }
markrad 0:cdf462088d13 394
markrad 0:cdf462088d13 395 fclose( f );
markrad 0:cdf462088d13 396
markrad 0:cdf462088d13 397 mbedtls_hmac_drbg_update( ctx, buf, n );
markrad 0:cdf462088d13 398
markrad 0:cdf462088d13 399 return( mbedtls_hmac_drbg_write_seed_file( ctx, path ) );
markrad 0:cdf462088d13 400 }
markrad 0:cdf462088d13 401 #endif /* MBEDTLS_FS_IO */
markrad 0:cdf462088d13 402
markrad 0:cdf462088d13 403
markrad 0:cdf462088d13 404 #if defined(MBEDTLS_SELF_TEST)
markrad 0:cdf462088d13 405
markrad 0:cdf462088d13 406 #if !defined(MBEDTLS_SHA1_C)
markrad 0:cdf462088d13 407 /* Dummy checkup routine */
markrad 0:cdf462088d13 408 int mbedtls_hmac_drbg_self_test( int verbose )
markrad 0:cdf462088d13 409 {
markrad 0:cdf462088d13 410 (void) verbose;
markrad 0:cdf462088d13 411 return( 0 );
markrad 0:cdf462088d13 412 }
markrad 0:cdf462088d13 413 #else
markrad 0:cdf462088d13 414
markrad 0:cdf462088d13 415 #define OUTPUT_LEN 80
markrad 0:cdf462088d13 416
markrad 0:cdf462088d13 417 /* From a NIST PR=true test vector */
markrad 0:cdf462088d13 418 static const unsigned char entropy_pr[] = {
markrad 0:cdf462088d13 419 0xa0, 0xc9, 0xab, 0x58, 0xf1, 0xe2, 0xe5, 0xa4, 0xde, 0x3e, 0xbd, 0x4f,
markrad 0:cdf462088d13 420 0xf7, 0x3e, 0x9c, 0x5b, 0x64, 0xef, 0xd8, 0xca, 0x02, 0x8c, 0xf8, 0x11,
markrad 0:cdf462088d13 421 0x48, 0xa5, 0x84, 0xfe, 0x69, 0xab, 0x5a, 0xee, 0x42, 0xaa, 0x4d, 0x42,
markrad 0:cdf462088d13 422 0x17, 0x60, 0x99, 0xd4, 0x5e, 0x13, 0x97, 0xdc, 0x40, 0x4d, 0x86, 0xa3,
markrad 0:cdf462088d13 423 0x7b, 0xf5, 0x59, 0x54, 0x75, 0x69, 0x51, 0xe4 };
markrad 0:cdf462088d13 424 static const unsigned char result_pr[OUTPUT_LEN] = {
markrad 0:cdf462088d13 425 0x9a, 0x00, 0xa2, 0xd0, 0x0e, 0xd5, 0x9b, 0xfe, 0x31, 0xec, 0xb1, 0x39,
markrad 0:cdf462088d13 426 0x9b, 0x60, 0x81, 0x48, 0xd1, 0x96, 0x9d, 0x25, 0x0d, 0x3c, 0x1e, 0x94,
markrad 0:cdf462088d13 427 0x10, 0x10, 0x98, 0x12, 0x93, 0x25, 0xca, 0xb8, 0xfc, 0xcc, 0x2d, 0x54,
markrad 0:cdf462088d13 428 0x73, 0x19, 0x70, 0xc0, 0x10, 0x7a, 0xa4, 0x89, 0x25, 0x19, 0x95, 0x5e,
markrad 0:cdf462088d13 429 0x4b, 0xc6, 0x00, 0x1d, 0x7f, 0x4e, 0x6a, 0x2b, 0xf8, 0xa3, 0x01, 0xab,
markrad 0:cdf462088d13 430 0x46, 0x05, 0x5c, 0x09, 0xa6, 0x71, 0x88, 0xf1, 0xa7, 0x40, 0xee, 0xf3,
markrad 0:cdf462088d13 431 0xe1, 0x5c, 0x02, 0x9b, 0x44, 0xaf, 0x03, 0x44 };
markrad 0:cdf462088d13 432
markrad 0:cdf462088d13 433 /* From a NIST PR=false test vector */
markrad 0:cdf462088d13 434 static const unsigned char entropy_nopr[] = {
markrad 0:cdf462088d13 435 0x79, 0x34, 0x9b, 0xbf, 0x7c, 0xdd, 0xa5, 0x79, 0x95, 0x57, 0x86, 0x66,
markrad 0:cdf462088d13 436 0x21, 0xc9, 0x13, 0x83, 0x11, 0x46, 0x73, 0x3a, 0xbf, 0x8c, 0x35, 0xc8,
markrad 0:cdf462088d13 437 0xc7, 0x21, 0x5b, 0x5b, 0x96, 0xc4, 0x8e, 0x9b, 0x33, 0x8c, 0x74, 0xe3,
markrad 0:cdf462088d13 438 0xe9, 0x9d, 0xfe, 0xdf };
markrad 0:cdf462088d13 439 static const unsigned char result_nopr[OUTPUT_LEN] = {
markrad 0:cdf462088d13 440 0xc6, 0xa1, 0x6a, 0xb8, 0xd4, 0x20, 0x70, 0x6f, 0x0f, 0x34, 0xab, 0x7f,
markrad 0:cdf462088d13 441 0xec, 0x5a, 0xdc, 0xa9, 0xd8, 0xca, 0x3a, 0x13, 0x3e, 0x15, 0x9c, 0xa6,
markrad 0:cdf462088d13 442 0xac, 0x43, 0xc6, 0xf8, 0xa2, 0xbe, 0x22, 0x83, 0x4a, 0x4c, 0x0a, 0x0a,
markrad 0:cdf462088d13 443 0xff, 0xb1, 0x0d, 0x71, 0x94, 0xf1, 0xc1, 0xa5, 0xcf, 0x73, 0x22, 0xec,
markrad 0:cdf462088d13 444 0x1a, 0xe0, 0x96, 0x4e, 0xd4, 0xbf, 0x12, 0x27, 0x46, 0xe0, 0x87, 0xfd,
markrad 0:cdf462088d13 445 0xb5, 0xb3, 0xe9, 0x1b, 0x34, 0x93, 0xd5, 0xbb, 0x98, 0xfa, 0xed, 0x49,
markrad 0:cdf462088d13 446 0xe8, 0x5f, 0x13, 0x0f, 0xc8, 0xa4, 0x59, 0xb7 };
markrad 0:cdf462088d13 447
markrad 0:cdf462088d13 448 /* "Entropy" from buffer */
markrad 0:cdf462088d13 449 static size_t test_offset;
markrad 0:cdf462088d13 450 static int hmac_drbg_self_test_entropy( void *data,
markrad 0:cdf462088d13 451 unsigned char *buf, size_t len )
markrad 0:cdf462088d13 452 {
markrad 0:cdf462088d13 453 const unsigned char *p = data;
markrad 0:cdf462088d13 454 memcpy( buf, p + test_offset, len );
markrad 0:cdf462088d13 455 test_offset += len;
markrad 0:cdf462088d13 456 return( 0 );
markrad 0:cdf462088d13 457 }
markrad 0:cdf462088d13 458
markrad 0:cdf462088d13 459 #define CHK( c ) if( (c) != 0 ) \
markrad 0:cdf462088d13 460 { \
markrad 0:cdf462088d13 461 if( verbose != 0 ) \
markrad 0:cdf462088d13 462 mbedtls_printf( "failed\n" ); \
markrad 0:cdf462088d13 463 return( 1 ); \
markrad 0:cdf462088d13 464 }
markrad 0:cdf462088d13 465
markrad 0:cdf462088d13 466 /*
markrad 0:cdf462088d13 467 * Checkup routine for HMAC_DRBG with SHA-1
markrad 0:cdf462088d13 468 */
markrad 0:cdf462088d13 469 int mbedtls_hmac_drbg_self_test( int verbose )
markrad 0:cdf462088d13 470 {
markrad 0:cdf462088d13 471 mbedtls_hmac_drbg_context ctx;
markrad 0:cdf462088d13 472 unsigned char buf[OUTPUT_LEN];
markrad 0:cdf462088d13 473 const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
markrad 0:cdf462088d13 474
markrad 0:cdf462088d13 475 mbedtls_hmac_drbg_init( &ctx );
markrad 0:cdf462088d13 476
markrad 0:cdf462088d13 477 /*
markrad 0:cdf462088d13 478 * PR = True
markrad 0:cdf462088d13 479 */
markrad 0:cdf462088d13 480 if( verbose != 0 )
markrad 0:cdf462088d13 481 mbedtls_printf( " HMAC_DRBG (PR = True) : " );
markrad 0:cdf462088d13 482
markrad 0:cdf462088d13 483 test_offset = 0;
markrad 0:cdf462088d13 484 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
markrad 0:cdf462088d13 485 hmac_drbg_self_test_entropy, (void *) entropy_pr,
markrad 0:cdf462088d13 486 NULL, 0 ) );
markrad 0:cdf462088d13 487 mbedtls_hmac_drbg_set_prediction_resistance( &ctx, MBEDTLS_HMAC_DRBG_PR_ON );
markrad 0:cdf462088d13 488 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
markrad 0:cdf462088d13 489 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
markrad 0:cdf462088d13 490 CHK( memcmp( buf, result_pr, OUTPUT_LEN ) );
markrad 0:cdf462088d13 491 mbedtls_hmac_drbg_free( &ctx );
markrad 0:cdf462088d13 492
markrad 0:cdf462088d13 493 mbedtls_hmac_drbg_free( &ctx );
markrad 0:cdf462088d13 494
markrad 0:cdf462088d13 495 if( verbose != 0 )
markrad 0:cdf462088d13 496 mbedtls_printf( "passed\n" );
markrad 0:cdf462088d13 497
markrad 0:cdf462088d13 498 /*
markrad 0:cdf462088d13 499 * PR = False
markrad 0:cdf462088d13 500 */
markrad 0:cdf462088d13 501 if( verbose != 0 )
markrad 0:cdf462088d13 502 mbedtls_printf( " HMAC_DRBG (PR = False) : " );
markrad 0:cdf462088d13 503
markrad 0:cdf462088d13 504 mbedtls_hmac_drbg_init( &ctx );
markrad 0:cdf462088d13 505
markrad 0:cdf462088d13 506 test_offset = 0;
markrad 0:cdf462088d13 507 CHK( mbedtls_hmac_drbg_seed( &ctx, md_info,
markrad 0:cdf462088d13 508 hmac_drbg_self_test_entropy, (void *) entropy_nopr,
markrad 0:cdf462088d13 509 NULL, 0 ) );
markrad 0:cdf462088d13 510 CHK( mbedtls_hmac_drbg_reseed( &ctx, NULL, 0 ) );
markrad 0:cdf462088d13 511 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
markrad 0:cdf462088d13 512 CHK( mbedtls_hmac_drbg_random( &ctx, buf, OUTPUT_LEN ) );
markrad 0:cdf462088d13 513 CHK( memcmp( buf, result_nopr, OUTPUT_LEN ) );
markrad 0:cdf462088d13 514 mbedtls_hmac_drbg_free( &ctx );
markrad 0:cdf462088d13 515
markrad 0:cdf462088d13 516 mbedtls_hmac_drbg_free( &ctx );
markrad 0:cdf462088d13 517
markrad 0:cdf462088d13 518 if( verbose != 0 )
markrad 0:cdf462088d13 519 mbedtls_printf( "passed\n" );
markrad 0:cdf462088d13 520
markrad 0:cdf462088d13 521 if( verbose != 0 )
markrad 0:cdf462088d13 522 mbedtls_printf( "\n" );
markrad 0:cdf462088d13 523
markrad 0:cdf462088d13 524 return( 0 );
markrad 0:cdf462088d13 525 }
markrad 0:cdf462088d13 526 #endif /* MBEDTLS_SHA1_C */
markrad 0:cdf462088d13 527 #endif /* MBEDTLS_SELF_TEST */
markrad 0:cdf462088d13 528
markrad 0:cdf462088d13 529 #endif /* MBEDTLS_HMAC_DRBG_C */