Maxim nexpaq / nexpaq_dev

Preliminary main mbed library for nexpaq development

features/mbedtls/src/entropy.c@1:d96dbedaebdb, 2016-11-04 (annotated)

Committer:
nexpaq
Date:
Fri Nov 04 20:54:50 2016 +0000
Revision:
1:d96dbedaebdb
Parent:
0:6c56fb4bc5f0 
Removed extra directories for other platforms

Who changed what in which revision?

UserRevisionLine numberNew contents of line
nexpaq 0:6c56fb4bc5f0 1 /*
nexpaq 0:6c56fb4bc5f0 2 * Entropy accumulator implementation
nexpaq 0:6c56fb4bc5f0 3 *
nexpaq 0:6c56fb4bc5f0 4 * Copyright (C) 2006-2016, 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 #if !defined(MBEDTLS_CONFIG_FILE)
nexpaq 0:6c56fb4bc5f0 23 #include "mbedtls/config.h"
nexpaq 0:6c56fb4bc5f0 24 #else
nexpaq 0:6c56fb4bc5f0 25 #include MBEDTLS_CONFIG_FILE
nexpaq 0:6c56fb4bc5f0 26 #endif
nexpaq 0:6c56fb4bc5f0 27
nexpaq 0:6c56fb4bc5f0 28 #if defined(MBEDTLS_ENTROPY_C)
nexpaq 0:6c56fb4bc5f0 29
nexpaq 0:6c56fb4bc5f0 30 #if defined(MBEDTLS_TEST_NULL_ENTROPY)
nexpaq 0:6c56fb4bc5f0 31 #warning "**** WARNING! MBEDTLS_TEST_NULL_ENTROPY defined! "
nexpaq 0:6c56fb4bc5f0 32 #warning "**** THIS BUILD HAS NO DEFINED ENTROPY SOURCES "
nexpaq 0:6c56fb4bc5f0 33 #warning "**** THIS BUILD IS *NOT* SUITABLE FOR PRODUCTION USE "
nexpaq 0:6c56fb4bc5f0 34 #endif
nexpaq 0:6c56fb4bc5f0 35
nexpaq 0:6c56fb4bc5f0 36 #include "mbedtls/entropy.h"
nexpaq 0:6c56fb4bc5f0 37 #include "mbedtls/entropy_poll.h"
nexpaq 0:6c56fb4bc5f0 38
nexpaq 0:6c56fb4bc5f0 39 #include <string.h>
nexpaq 0:6c56fb4bc5f0 40
nexpaq 0:6c56fb4bc5f0 41 #if defined(MBEDTLS_FS_IO)
nexpaq 0:6c56fb4bc5f0 42 #include <stdio.h>
nexpaq 0:6c56fb4bc5f0 43 #endif
nexpaq 0:6c56fb4bc5f0 44
nexpaq 0:6c56fb4bc5f0 45 #if defined(MBEDTLS_SELF_TEST)
nexpaq 0:6c56fb4bc5f0 46 #if defined(MBEDTLS_PLATFORM_C)
nexpaq 0:6c56fb4bc5f0 47 #include "mbedtls/platform.h"
nexpaq 0:6c56fb4bc5f0 48 #else
nexpaq 0:6c56fb4bc5f0 49 #include <stdio.h>
nexpaq 0:6c56fb4bc5f0 50 #define mbedtls_printf printf
nexpaq 0:6c56fb4bc5f0 51 #endif /* MBEDTLS_PLATFORM_C */
nexpaq 0:6c56fb4bc5f0 52 #endif /* MBEDTLS_SELF_TEST */
nexpaq 0:6c56fb4bc5f0 53
nexpaq 0:6c56fb4bc5f0 54 #if defined(MBEDTLS_HAVEGE_C)
nexpaq 0:6c56fb4bc5f0 55 #include "mbedtls/havege.h"
nexpaq 0:6c56fb4bc5f0 56 #endif
nexpaq 0:6c56fb4bc5f0 57
nexpaq 0:6c56fb4bc5f0 58 /* Implementation that should never be optimized out by the compiler */
nexpaq 0:6c56fb4bc5f0 59 static void mbedtls_zeroize( void *v, size_t n ) {
nexpaq 0:6c56fb4bc5f0 60 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
nexpaq 0:6c56fb4bc5f0 61 }
nexpaq 0:6c56fb4bc5f0 62
nexpaq 0:6c56fb4bc5f0 63 #define ENTROPY_MAX_LOOP 256 /**< Maximum amount to loop before error */
nexpaq 0:6c56fb4bc5f0 64
nexpaq 0:6c56fb4bc5f0 65 void mbedtls_entropy_init( mbedtls_entropy_context *ctx )
nexpaq 0:6c56fb4bc5f0 66 {
nexpaq 0:6c56fb4bc5f0 67 memset( ctx, 0, sizeof(mbedtls_entropy_context) );
nexpaq 0:6c56fb4bc5f0 68
nexpaq 0:6c56fb4bc5f0 69 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 70 mbedtls_mutex_init( &ctx->mutex );
nexpaq 0:6c56fb4bc5f0 71 #endif
nexpaq 0:6c56fb4bc5f0 72
nexpaq 0:6c56fb4bc5f0 73 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
nexpaq 0:6c56fb4bc5f0 74 mbedtls_sha512_starts( &ctx->accumulator, 0 );
nexpaq 0:6c56fb4bc5f0 75 #else
nexpaq 0:6c56fb4bc5f0 76 mbedtls_sha256_starts( &ctx->accumulator, 0 );
nexpaq 0:6c56fb4bc5f0 77 #endif
nexpaq 0:6c56fb4bc5f0 78 #if defined(MBEDTLS_HAVEGE_C)
nexpaq 0:6c56fb4bc5f0 79 mbedtls_havege_init( &ctx->havege_data );
nexpaq 0:6c56fb4bc5f0 80 #endif
nexpaq 0:6c56fb4bc5f0 81
nexpaq 0:6c56fb4bc5f0 82 #if defined(MBEDTLS_TEST_NULL_ENTROPY)
nexpaq 0:6c56fb4bc5f0 83 mbedtls_entropy_add_source( ctx, mbedtls_null_entropy_poll, NULL,
nexpaq 0:6c56fb4bc5f0 84 1, MBEDTLS_ENTROPY_SOURCE_STRONG );
nexpaq 0:6c56fb4bc5f0 85 #endif
nexpaq 0:6c56fb4bc5f0 86
nexpaq 0:6c56fb4bc5f0 87 #if !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
nexpaq 0:6c56fb4bc5f0 88 #if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
nexpaq 0:6c56fb4bc5f0 89 mbedtls_entropy_add_source( ctx, mbedtls_platform_entropy_poll, NULL,
nexpaq 0:6c56fb4bc5f0 90 MBEDTLS_ENTROPY_MIN_PLATFORM,
nexpaq 0:6c56fb4bc5f0 91 MBEDTLS_ENTROPY_SOURCE_STRONG );
nexpaq 0:6c56fb4bc5f0 92 #endif
nexpaq 0:6c56fb4bc5f0 93 #if defined(MBEDTLS_TIMING_C)
nexpaq 0:6c56fb4bc5f0 94 mbedtls_entropy_add_source( ctx, mbedtls_hardclock_poll, NULL,
nexpaq 0:6c56fb4bc5f0 95 MBEDTLS_ENTROPY_MIN_HARDCLOCK,
nexpaq 0:6c56fb4bc5f0 96 MBEDTLS_ENTROPY_SOURCE_WEAK );
nexpaq 0:6c56fb4bc5f0 97 #endif
nexpaq 0:6c56fb4bc5f0 98 #if defined(MBEDTLS_HAVEGE_C)
nexpaq 0:6c56fb4bc5f0 99 mbedtls_entropy_add_source( ctx, mbedtls_havege_poll, &ctx->havege_data,
nexpaq 0:6c56fb4bc5f0 100 MBEDTLS_ENTROPY_MIN_HAVEGE,
nexpaq 0:6c56fb4bc5f0 101 MBEDTLS_ENTROPY_SOURCE_STRONG );
nexpaq 0:6c56fb4bc5f0 102 #endif
nexpaq 0:6c56fb4bc5f0 103 #if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
nexpaq 0:6c56fb4bc5f0 104 mbedtls_entropy_add_source( ctx, mbedtls_hardware_poll, NULL,
nexpaq 0:6c56fb4bc5f0 105 MBEDTLS_ENTROPY_MIN_HARDWARE,
nexpaq 0:6c56fb4bc5f0 106 MBEDTLS_ENTROPY_SOURCE_STRONG );
nexpaq 0:6c56fb4bc5f0 107 #endif
nexpaq 0:6c56fb4bc5f0 108 #if defined(MBEDTLS_ENTROPY_NV_SEED)
nexpaq 0:6c56fb4bc5f0 109 mbedtls_entropy_add_source( ctx, mbedtls_nv_seed_poll, NULL,
nexpaq 0:6c56fb4bc5f0 110 MBEDTLS_ENTROPY_BLOCK_SIZE,
nexpaq 0:6c56fb4bc5f0 111 MBEDTLS_ENTROPY_SOURCE_STRONG );
nexpaq 0:6c56fb4bc5f0 112 #endif
nexpaq 0:6c56fb4bc5f0 113 #endif /* MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES */
nexpaq 0:6c56fb4bc5f0 114 }
nexpaq 0:6c56fb4bc5f0 115
nexpaq 0:6c56fb4bc5f0 116 void mbedtls_entropy_free( mbedtls_entropy_context *ctx )
nexpaq 0:6c56fb4bc5f0 117 {
nexpaq 0:6c56fb4bc5f0 118 #if defined(MBEDTLS_HAVEGE_C)
nexpaq 0:6c56fb4bc5f0 119 mbedtls_havege_free( &ctx->havege_data );
nexpaq 0:6c56fb4bc5f0 120 #endif
nexpaq 0:6c56fb4bc5f0 121 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 122 mbedtls_mutex_free( &ctx->mutex );
nexpaq 0:6c56fb4bc5f0 123 #endif
nexpaq 0:6c56fb4bc5f0 124 mbedtls_zeroize( ctx, sizeof( mbedtls_entropy_context ) );
nexpaq 0:6c56fb4bc5f0 125 }
nexpaq 0:6c56fb4bc5f0 126
nexpaq 0:6c56fb4bc5f0 127 int mbedtls_entropy_add_source( mbedtls_entropy_context *ctx,
nexpaq 0:6c56fb4bc5f0 128 mbedtls_entropy_f_source_ptr f_source, void *p_source,
nexpaq 0:6c56fb4bc5f0 129 size_t threshold, int strong )
nexpaq 0:6c56fb4bc5f0 130 {
nexpaq 0:6c56fb4bc5f0 131 int index, ret = 0;
nexpaq 0:6c56fb4bc5f0 132
nexpaq 0:6c56fb4bc5f0 133 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 134 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 135 return( ret );
nexpaq 0:6c56fb4bc5f0 136 #endif
nexpaq 0:6c56fb4bc5f0 137
nexpaq 0:6c56fb4bc5f0 138 index = ctx->source_count;
nexpaq 0:6c56fb4bc5f0 139 if( index >= MBEDTLS_ENTROPY_MAX_SOURCES )
nexpaq 0:6c56fb4bc5f0 140 {
nexpaq 0:6c56fb4bc5f0 141 ret = MBEDTLS_ERR_ENTROPY_MAX_SOURCES;
nexpaq 0:6c56fb4bc5f0 142 goto exit;
nexpaq 0:6c56fb4bc5f0 143 }
nexpaq 0:6c56fb4bc5f0 144
nexpaq 0:6c56fb4bc5f0 145 ctx->source[index].f_source = f_source;
nexpaq 0:6c56fb4bc5f0 146 ctx->source[index].p_source = p_source;
nexpaq 0:6c56fb4bc5f0 147 ctx->source[index].threshold = threshold;
nexpaq 0:6c56fb4bc5f0 148 ctx->source[index].strong = strong;
nexpaq 0:6c56fb4bc5f0 149
nexpaq 0:6c56fb4bc5f0 150 ctx->source_count++;
nexpaq 0:6c56fb4bc5f0 151
nexpaq 0:6c56fb4bc5f0 152 exit:
nexpaq 0:6c56fb4bc5f0 153 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 154 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
nexpaq 0:6c56fb4bc5f0 155 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
nexpaq 0:6c56fb4bc5f0 156 #endif
nexpaq 0:6c56fb4bc5f0 157
nexpaq 0:6c56fb4bc5f0 158 return( ret );
nexpaq 0:6c56fb4bc5f0 159 }
nexpaq 0:6c56fb4bc5f0 160
nexpaq 0:6c56fb4bc5f0 161 /*
nexpaq 0:6c56fb4bc5f0 162 * Entropy accumulator update
nexpaq 0:6c56fb4bc5f0 163 */
nexpaq 0:6c56fb4bc5f0 164 static int entropy_update( mbedtls_entropy_context *ctx, unsigned char source_id,
nexpaq 0:6c56fb4bc5f0 165 const unsigned char *data, size_t len )
nexpaq 0:6c56fb4bc5f0 166 {
nexpaq 0:6c56fb4bc5f0 167 unsigned char header[2];
nexpaq 0:6c56fb4bc5f0 168 unsigned char tmp[MBEDTLS_ENTROPY_BLOCK_SIZE];
nexpaq 0:6c56fb4bc5f0 169 size_t use_len = len;
nexpaq 0:6c56fb4bc5f0 170 const unsigned char *p = data;
nexpaq 0:6c56fb4bc5f0 171
nexpaq 0:6c56fb4bc5f0 172 if( use_len > MBEDTLS_ENTROPY_BLOCK_SIZE )
nexpaq 0:6c56fb4bc5f0 173 {
nexpaq 0:6c56fb4bc5f0 174 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
nexpaq 0:6c56fb4bc5f0 175 mbedtls_sha512( data, len, tmp, 0 );
nexpaq 0:6c56fb4bc5f0 176 #else
nexpaq 0:6c56fb4bc5f0 177 mbedtls_sha256( data, len, tmp, 0 );
nexpaq 0:6c56fb4bc5f0 178 #endif
nexpaq 0:6c56fb4bc5f0 179 p = tmp;
nexpaq 0:6c56fb4bc5f0 180 use_len = MBEDTLS_ENTROPY_BLOCK_SIZE;
nexpaq 0:6c56fb4bc5f0 181 }
nexpaq 0:6c56fb4bc5f0 182
nexpaq 0:6c56fb4bc5f0 183 header[0] = source_id;
nexpaq 0:6c56fb4bc5f0 184 header[1] = use_len & 0xFF;
nexpaq 0:6c56fb4bc5f0 185
nexpaq 0:6c56fb4bc5f0 186 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
nexpaq 0:6c56fb4bc5f0 187 mbedtls_sha512_update( &ctx->accumulator, header, 2 );
nexpaq 0:6c56fb4bc5f0 188 mbedtls_sha512_update( &ctx->accumulator, p, use_len );
nexpaq 0:6c56fb4bc5f0 189 #else
nexpaq 0:6c56fb4bc5f0 190 mbedtls_sha256_update( &ctx->accumulator, header, 2 );
nexpaq 0:6c56fb4bc5f0 191 mbedtls_sha256_update( &ctx->accumulator, p, use_len );
nexpaq 0:6c56fb4bc5f0 192 #endif
nexpaq 0:6c56fb4bc5f0 193
nexpaq 0:6c56fb4bc5f0 194 return( 0 );
nexpaq 0:6c56fb4bc5f0 195 }
nexpaq 0:6c56fb4bc5f0 196
nexpaq 0:6c56fb4bc5f0 197 int mbedtls_entropy_update_manual( mbedtls_entropy_context *ctx,
nexpaq 0:6c56fb4bc5f0 198 const unsigned char *data, size_t len )
nexpaq 0:6c56fb4bc5f0 199 {
nexpaq 0:6c56fb4bc5f0 200 int ret;
nexpaq 0:6c56fb4bc5f0 201
nexpaq 0:6c56fb4bc5f0 202 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 203 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 204 return( ret );
nexpaq 0:6c56fb4bc5f0 205 #endif
nexpaq 0:6c56fb4bc5f0 206
nexpaq 0:6c56fb4bc5f0 207 ret = entropy_update( ctx, MBEDTLS_ENTROPY_SOURCE_MANUAL, data, len );
nexpaq 0:6c56fb4bc5f0 208
nexpaq 0:6c56fb4bc5f0 209 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 210 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
nexpaq 0:6c56fb4bc5f0 211 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
nexpaq 0:6c56fb4bc5f0 212 #endif
nexpaq 0:6c56fb4bc5f0 213
nexpaq 0:6c56fb4bc5f0 214 return( ret );
nexpaq 0:6c56fb4bc5f0 215 }
nexpaq 0:6c56fb4bc5f0 216
nexpaq 0:6c56fb4bc5f0 217 /*
nexpaq 0:6c56fb4bc5f0 218 * Run through the different sources to add entropy to our accumulator
nexpaq 0:6c56fb4bc5f0 219 */
nexpaq 0:6c56fb4bc5f0 220 static int entropy_gather_internal( mbedtls_entropy_context *ctx )
nexpaq 0:6c56fb4bc5f0 221 {
nexpaq 0:6c56fb4bc5f0 222 int ret, i, have_one_strong = 0;
nexpaq 0:6c56fb4bc5f0 223 unsigned char buf[MBEDTLS_ENTROPY_MAX_GATHER];
nexpaq 0:6c56fb4bc5f0 224 size_t olen;
nexpaq 0:6c56fb4bc5f0 225
nexpaq 0:6c56fb4bc5f0 226 if( ctx->source_count == 0 )
nexpaq 0:6c56fb4bc5f0 227 return( MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED );
nexpaq 0:6c56fb4bc5f0 228
nexpaq 0:6c56fb4bc5f0 229 /*
nexpaq 0:6c56fb4bc5f0 230 * Run through our entropy sources
nexpaq 0:6c56fb4bc5f0 231 */
nexpaq 0:6c56fb4bc5f0 232 for( i = 0; i < ctx->source_count; i++ )
nexpaq 0:6c56fb4bc5f0 233 {
nexpaq 0:6c56fb4bc5f0 234 if( ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG )
nexpaq 0:6c56fb4bc5f0 235 have_one_strong = 1;
nexpaq 0:6c56fb4bc5f0 236
nexpaq 0:6c56fb4bc5f0 237 olen = 0;
nexpaq 0:6c56fb4bc5f0 238 if( ( ret = ctx->source[i].f_source( ctx->source[i].p_source,
nexpaq 0:6c56fb4bc5f0 239 buf, MBEDTLS_ENTROPY_MAX_GATHER, &olen ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 240 {
nexpaq 0:6c56fb4bc5f0 241 return( ret );
nexpaq 0:6c56fb4bc5f0 242 }
nexpaq 0:6c56fb4bc5f0 243
nexpaq 0:6c56fb4bc5f0 244 /*
nexpaq 0:6c56fb4bc5f0 245 * Add if we actually gathered something
nexpaq 0:6c56fb4bc5f0 246 */
nexpaq 0:6c56fb4bc5f0 247 if( olen > 0 )
nexpaq 0:6c56fb4bc5f0 248 {
nexpaq 0:6c56fb4bc5f0 249 entropy_update( ctx, (unsigned char) i, buf, olen );
nexpaq 0:6c56fb4bc5f0 250 ctx->source[i].size += olen;
nexpaq 0:6c56fb4bc5f0 251 }
nexpaq 0:6c56fb4bc5f0 252 }
nexpaq 0:6c56fb4bc5f0 253
nexpaq 0:6c56fb4bc5f0 254 if( have_one_strong == 0 )
nexpaq 0:6c56fb4bc5f0 255 return( MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE );
nexpaq 0:6c56fb4bc5f0 256
nexpaq 0:6c56fb4bc5f0 257 return( 0 );
nexpaq 0:6c56fb4bc5f0 258 }
nexpaq 0:6c56fb4bc5f0 259
nexpaq 0:6c56fb4bc5f0 260 /*
nexpaq 0:6c56fb4bc5f0 261 * Thread-safe wrapper for entropy_gather_internal()
nexpaq 0:6c56fb4bc5f0 262 */
nexpaq 0:6c56fb4bc5f0 263 int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
nexpaq 0:6c56fb4bc5f0 264 {
nexpaq 0:6c56fb4bc5f0 265 int ret;
nexpaq 0:6c56fb4bc5f0 266
nexpaq 0:6c56fb4bc5f0 267 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 268 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 269 return( ret );
nexpaq 0:6c56fb4bc5f0 270 #endif
nexpaq 0:6c56fb4bc5f0 271
nexpaq 0:6c56fb4bc5f0 272 ret = entropy_gather_internal( ctx );
nexpaq 0:6c56fb4bc5f0 273
nexpaq 0:6c56fb4bc5f0 274 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 275 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
nexpaq 0:6c56fb4bc5f0 276 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
nexpaq 0:6c56fb4bc5f0 277 #endif
nexpaq 0:6c56fb4bc5f0 278
nexpaq 0:6c56fb4bc5f0 279 return( ret );
nexpaq 0:6c56fb4bc5f0 280 }
nexpaq 0:6c56fb4bc5f0 281
nexpaq 0:6c56fb4bc5f0 282 int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
nexpaq 0:6c56fb4bc5f0 283 {
nexpaq 0:6c56fb4bc5f0 284 int ret, count = 0, i, done;
nexpaq 0:6c56fb4bc5f0 285 mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
nexpaq 0:6c56fb4bc5f0 286 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
nexpaq 0:6c56fb4bc5f0 287
nexpaq 0:6c56fb4bc5f0 288 if( len > MBEDTLS_ENTROPY_BLOCK_SIZE )
nexpaq 0:6c56fb4bc5f0 289 return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
nexpaq 0:6c56fb4bc5f0 290
nexpaq 0:6c56fb4bc5f0 291 #if defined(MBEDTLS_ENTROPY_NV_SEED)
nexpaq 0:6c56fb4bc5f0 292 /* Update the NV entropy seed before generating any entropy for outside
nexpaq 0:6c56fb4bc5f0 293 * use.
nexpaq 0:6c56fb4bc5f0 294 */
nexpaq 0:6c56fb4bc5f0 295 if( ctx->initial_entropy_run == 0 )
nexpaq 0:6c56fb4bc5f0 296 {
nexpaq 0:6c56fb4bc5f0 297 ctx->initial_entropy_run = 1;
nexpaq 0:6c56fb4bc5f0 298 if( ( ret = mbedtls_entropy_update_nv_seed( ctx ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 299 return( ret );
nexpaq 0:6c56fb4bc5f0 300 }
nexpaq 0:6c56fb4bc5f0 301 #endif
nexpaq 0:6c56fb4bc5f0 302
nexpaq 0:6c56fb4bc5f0 303 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 304 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 305 return( ret );
nexpaq 0:6c56fb4bc5f0 306 #endif
nexpaq 0:6c56fb4bc5f0 307
nexpaq 0:6c56fb4bc5f0 308 /*
nexpaq 0:6c56fb4bc5f0 309 * Always gather extra entropy before a call
nexpaq 0:6c56fb4bc5f0 310 */
nexpaq 0:6c56fb4bc5f0 311 do
nexpaq 0:6c56fb4bc5f0 312 {
nexpaq 0:6c56fb4bc5f0 313 if( count++ > ENTROPY_MAX_LOOP )
nexpaq 0:6c56fb4bc5f0 314 {
nexpaq 0:6c56fb4bc5f0 315 ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
nexpaq 0:6c56fb4bc5f0 316 goto exit;
nexpaq 0:6c56fb4bc5f0 317 }
nexpaq 0:6c56fb4bc5f0 318
nexpaq 0:6c56fb4bc5f0 319 if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 320 goto exit;
nexpaq 0:6c56fb4bc5f0 321
nexpaq 0:6c56fb4bc5f0 322 done = 1;
nexpaq 0:6c56fb4bc5f0 323 for( i = 0; i < ctx->source_count; i++ )
nexpaq 0:6c56fb4bc5f0 324 if( ctx->source[i].size < ctx->source[i].threshold )
nexpaq 0:6c56fb4bc5f0 325 done = 0;
nexpaq 0:6c56fb4bc5f0 326 }
nexpaq 0:6c56fb4bc5f0 327 while( ! done );
nexpaq 0:6c56fb4bc5f0 328
nexpaq 0:6c56fb4bc5f0 329 memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
nexpaq 0:6c56fb4bc5f0 330
nexpaq 0:6c56fb4bc5f0 331 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
nexpaq 0:6c56fb4bc5f0 332 mbedtls_sha512_finish( &ctx->accumulator, buf );
nexpaq 0:6c56fb4bc5f0 333
nexpaq 0:6c56fb4bc5f0 334 /*
nexpaq 0:6c56fb4bc5f0 335 * Reset accumulator and counters and recycle existing entropy
nexpaq 0:6c56fb4bc5f0 336 */
nexpaq 0:6c56fb4bc5f0 337 memset( &ctx->accumulator, 0, sizeof( mbedtls_sha512_context ) );
nexpaq 0:6c56fb4bc5f0 338 mbedtls_sha512_starts( &ctx->accumulator, 0 );
nexpaq 0:6c56fb4bc5f0 339 mbedtls_sha512_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
nexpaq 0:6c56fb4bc5f0 340
nexpaq 0:6c56fb4bc5f0 341 /*
nexpaq 0:6c56fb4bc5f0 342 * Perform second SHA-512 on entropy
nexpaq 0:6c56fb4bc5f0 343 */
nexpaq 0:6c56fb4bc5f0 344 mbedtls_sha512( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
nexpaq 0:6c56fb4bc5f0 345 #else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
nexpaq 0:6c56fb4bc5f0 346 mbedtls_sha256_finish( &ctx->accumulator, buf );
nexpaq 0:6c56fb4bc5f0 347
nexpaq 0:6c56fb4bc5f0 348 /*
nexpaq 0:6c56fb4bc5f0 349 * Reset accumulator and counters and recycle existing entropy
nexpaq 0:6c56fb4bc5f0 350 */
nexpaq 0:6c56fb4bc5f0 351 memset( &ctx->accumulator, 0, sizeof( mbedtls_sha256_context ) );
nexpaq 0:6c56fb4bc5f0 352 mbedtls_sha256_starts( &ctx->accumulator, 0 );
nexpaq 0:6c56fb4bc5f0 353 mbedtls_sha256_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
nexpaq 0:6c56fb4bc5f0 354
nexpaq 0:6c56fb4bc5f0 355 /*
nexpaq 0:6c56fb4bc5f0 356 * Perform second SHA-256 on entropy
nexpaq 0:6c56fb4bc5f0 357 */
nexpaq 0:6c56fb4bc5f0 358 mbedtls_sha256( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
nexpaq 0:6c56fb4bc5f0 359 #endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
nexpaq 0:6c56fb4bc5f0 360
nexpaq 0:6c56fb4bc5f0 361 for( i = 0; i < ctx->source_count; i++ )
nexpaq 0:6c56fb4bc5f0 362 ctx->source[i].size = 0;
nexpaq 0:6c56fb4bc5f0 363
nexpaq 0:6c56fb4bc5f0 364 memcpy( output, buf, len );
nexpaq 0:6c56fb4bc5f0 365
nexpaq 0:6c56fb4bc5f0 366 ret = 0;
nexpaq 0:6c56fb4bc5f0 367
nexpaq 0:6c56fb4bc5f0 368 exit:
nexpaq 0:6c56fb4bc5f0 369 #if defined(MBEDTLS_THREADING_C)
nexpaq 0:6c56fb4bc5f0 370 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
nexpaq 0:6c56fb4bc5f0 371 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
nexpaq 0:6c56fb4bc5f0 372 #endif
nexpaq 0:6c56fb4bc5f0 373
nexpaq 0:6c56fb4bc5f0 374 return( ret );
nexpaq 0:6c56fb4bc5f0 375 }
nexpaq 0:6c56fb4bc5f0 376
nexpaq 0:6c56fb4bc5f0 377 #if defined(MBEDTLS_ENTROPY_NV_SEED)
nexpaq 0:6c56fb4bc5f0 378 int mbedtls_entropy_update_nv_seed( mbedtls_entropy_context *ctx )
nexpaq 0:6c56fb4bc5f0 379 {
nexpaq 0:6c56fb4bc5f0 380 int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
nexpaq 0:6c56fb4bc5f0 381 unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
nexpaq 0:6c56fb4bc5f0 382
nexpaq 0:6c56fb4bc5f0 383 /* Read new seed and write it to NV */
nexpaq 0:6c56fb4bc5f0 384 if( ( ret = mbedtls_entropy_func( ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 385 return( ret );
nexpaq 0:6c56fb4bc5f0 386
nexpaq 0:6c56fb4bc5f0 387 if( mbedtls_nv_seed_write( buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) < 0 )
nexpaq 0:6c56fb4bc5f0 388 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 389
nexpaq 0:6c56fb4bc5f0 390 /* Manually update the remaining stream with a separator value to diverge */
nexpaq 0:6c56fb4bc5f0 391 memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
nexpaq 0:6c56fb4bc5f0 392 mbedtls_entropy_update_manual( ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
nexpaq 0:6c56fb4bc5f0 393
nexpaq 0:6c56fb4bc5f0 394 return( 0 );
nexpaq 0:6c56fb4bc5f0 395 }
nexpaq 0:6c56fb4bc5f0 396 #endif /* MBEDTLS_ENTROPY_NV_SEED */
nexpaq 0:6c56fb4bc5f0 397
nexpaq 0:6c56fb4bc5f0 398 #if defined(MBEDTLS_FS_IO)
nexpaq 0:6c56fb4bc5f0 399 int mbedtls_entropy_write_seed_file( mbedtls_entropy_context *ctx, const char *path )
nexpaq 0:6c56fb4bc5f0 400 {
nexpaq 0:6c56fb4bc5f0 401 int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
nexpaq 0:6c56fb4bc5f0 402 FILE *f;
nexpaq 0:6c56fb4bc5f0 403 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
nexpaq 0:6c56fb4bc5f0 404
nexpaq 0:6c56fb4bc5f0 405 if( ( f = fopen( path, "wb" ) ) == NULL )
nexpaq 0:6c56fb4bc5f0 406 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 407
nexpaq 0:6c56fb4bc5f0 408 if( ( ret = mbedtls_entropy_func( ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 409 goto exit;
nexpaq 0:6c56fb4bc5f0 410
nexpaq 0:6c56fb4bc5f0 411 if( fwrite( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) != MBEDTLS_ENTROPY_BLOCK_SIZE )
nexpaq 0:6c56fb4bc5f0 412 {
nexpaq 0:6c56fb4bc5f0 413 ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
nexpaq 0:6c56fb4bc5f0 414 goto exit;
nexpaq 0:6c56fb4bc5f0 415 }
nexpaq 0:6c56fb4bc5f0 416
nexpaq 0:6c56fb4bc5f0 417 ret = 0;
nexpaq 0:6c56fb4bc5f0 418
nexpaq 0:6c56fb4bc5f0 419 exit:
nexpaq 0:6c56fb4bc5f0 420 fclose( f );
nexpaq 0:6c56fb4bc5f0 421 return( ret );
nexpaq 0:6c56fb4bc5f0 422 }
nexpaq 0:6c56fb4bc5f0 423
nexpaq 0:6c56fb4bc5f0 424 int mbedtls_entropy_update_seed_file( mbedtls_entropy_context *ctx, const char *path )
nexpaq 0:6c56fb4bc5f0 425 {
nexpaq 0:6c56fb4bc5f0 426 FILE *f;
nexpaq 0:6c56fb4bc5f0 427 size_t n;
nexpaq 0:6c56fb4bc5f0 428 unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
nexpaq 0:6c56fb4bc5f0 429
nexpaq 0:6c56fb4bc5f0 430 if( ( f = fopen( path, "rb" ) ) == NULL )
nexpaq 0:6c56fb4bc5f0 431 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 432
nexpaq 0:6c56fb4bc5f0 433 fseek( f, 0, SEEK_END );
nexpaq 0:6c56fb4bc5f0 434 n = (size_t) ftell( f );
nexpaq 0:6c56fb4bc5f0 435 fseek( f, 0, SEEK_SET );
nexpaq 0:6c56fb4bc5f0 436
nexpaq 0:6c56fb4bc5f0 437 if( n > MBEDTLS_ENTROPY_MAX_SEED_SIZE )
nexpaq 0:6c56fb4bc5f0 438 n = MBEDTLS_ENTROPY_MAX_SEED_SIZE;
nexpaq 0:6c56fb4bc5f0 439
nexpaq 0:6c56fb4bc5f0 440 if( fread( buf, 1, n, f ) != n )
nexpaq 0:6c56fb4bc5f0 441 {
nexpaq 0:6c56fb4bc5f0 442 fclose( f );
nexpaq 0:6c56fb4bc5f0 443 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
nexpaq 0:6c56fb4bc5f0 444 }
nexpaq 0:6c56fb4bc5f0 445
nexpaq 0:6c56fb4bc5f0 446 fclose( f );
nexpaq 0:6c56fb4bc5f0 447
nexpaq 0:6c56fb4bc5f0 448 mbedtls_entropy_update_manual( ctx, buf, n );
nexpaq 0:6c56fb4bc5f0 449
nexpaq 0:6c56fb4bc5f0 450 return( mbedtls_entropy_write_seed_file( ctx, path ) );
nexpaq 0:6c56fb4bc5f0 451 }
nexpaq 0:6c56fb4bc5f0 452 #endif /* MBEDTLS_FS_IO */
nexpaq 0:6c56fb4bc5f0 453
nexpaq 0:6c56fb4bc5f0 454 #if defined(MBEDTLS_SELF_TEST)
nexpaq 0:6c56fb4bc5f0 455 /*
nexpaq 0:6c56fb4bc5f0 456 * Dummy source function
nexpaq 0:6c56fb4bc5f0 457 */
nexpaq 0:6c56fb4bc5f0 458 static int entropy_dummy_source( void *data, unsigned char *output,
nexpaq 0:6c56fb4bc5f0 459 size_t len, size_t *olen )
nexpaq 0:6c56fb4bc5f0 460 {
nexpaq 0:6c56fb4bc5f0 461 ((void) data);
nexpaq 0:6c56fb4bc5f0 462
nexpaq 0:6c56fb4bc5f0 463 memset( output, 0x2a, len );
nexpaq 0:6c56fb4bc5f0 464 *olen = len;
nexpaq 0:6c56fb4bc5f0 465
nexpaq 0:6c56fb4bc5f0 466 return( 0 );
nexpaq 0:6c56fb4bc5f0 467 }
nexpaq 0:6c56fb4bc5f0 468
nexpaq 0:6c56fb4bc5f0 469 /*
nexpaq 0:6c56fb4bc5f0 470 * The actual entropy quality is hard to test, but we can at least
nexpaq 0:6c56fb4bc5f0 471 * test that the functions don't cause errors and write the correct
nexpaq 0:6c56fb4bc5f0 472 * amount of data to buffers.
nexpaq 0:6c56fb4bc5f0 473 */
nexpaq 0:6c56fb4bc5f0 474 int mbedtls_entropy_self_test( int verbose )
nexpaq 0:6c56fb4bc5f0 475 {
nexpaq 0:6c56fb4bc5f0 476 int ret = 0;
nexpaq 0:6c56fb4bc5f0 477 mbedtls_entropy_context ctx;
nexpaq 0:6c56fb4bc5f0 478 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
nexpaq 0:6c56fb4bc5f0 479 unsigned char acc[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
nexpaq 0:6c56fb4bc5f0 480 size_t i, j;
nexpaq 0:6c56fb4bc5f0 481
nexpaq 0:6c56fb4bc5f0 482 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 483 mbedtls_printf( " ENTROPY test: " );
nexpaq 0:6c56fb4bc5f0 484
nexpaq 0:6c56fb4bc5f0 485 mbedtls_entropy_init( &ctx );
nexpaq 0:6c56fb4bc5f0 486
nexpaq 0:6c56fb4bc5f0 487 /* First do a gather to make sure we have default sources */
nexpaq 0:6c56fb4bc5f0 488 if( ( ret = mbedtls_entropy_gather( &ctx ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 489 goto cleanup;
nexpaq 0:6c56fb4bc5f0 490
nexpaq 0:6c56fb4bc5f0 491 ret = mbedtls_entropy_add_source( &ctx, entropy_dummy_source, NULL, 16,
nexpaq 0:6c56fb4bc5f0 492 MBEDTLS_ENTROPY_SOURCE_WEAK );
nexpaq 0:6c56fb4bc5f0 493 if( ret != 0 )
nexpaq 0:6c56fb4bc5f0 494 goto cleanup;
nexpaq 0:6c56fb4bc5f0 495
nexpaq 0:6c56fb4bc5f0 496 if( ( ret = mbedtls_entropy_update_manual( &ctx, buf, sizeof buf ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 497 goto cleanup;
nexpaq 0:6c56fb4bc5f0 498
nexpaq 0:6c56fb4bc5f0 499 /*
nexpaq 0:6c56fb4bc5f0 500 * To test that mbedtls_entropy_func writes correct number of bytes:
nexpaq 0:6c56fb4bc5f0 501 * - use the whole buffer and rely on ASan to detect overruns
nexpaq 0:6c56fb4bc5f0 502 * - collect entropy 8 times and OR the result in an accumulator:
nexpaq 0:6c56fb4bc5f0 503 * any byte should then be 0 with probably 2^(-64), so requiring
nexpaq 0:6c56fb4bc5f0 504 * each of the 32 or 64 bytes to be non-zero has a false failure rate
nexpaq 0:6c56fb4bc5f0 505 * of at most 2^(-58) which is acceptable.
nexpaq 0:6c56fb4bc5f0 506 */
nexpaq 0:6c56fb4bc5f0 507 for( i = 0; i < 8; i++ )
nexpaq 0:6c56fb4bc5f0 508 {
nexpaq 0:6c56fb4bc5f0 509 if( ( ret = mbedtls_entropy_func( &ctx, buf, sizeof( buf ) ) ) != 0 )
nexpaq 0:6c56fb4bc5f0 510 goto cleanup;
nexpaq 0:6c56fb4bc5f0 511
nexpaq 0:6c56fb4bc5f0 512 for( j = 0; j < sizeof( buf ); j++ )
nexpaq 0:6c56fb4bc5f0 513 acc[j] |= buf[j];
nexpaq 0:6c56fb4bc5f0 514 }
nexpaq 0:6c56fb4bc5f0 515
nexpaq 0:6c56fb4bc5f0 516 for( j = 0; j < sizeof( buf ); j++ )
nexpaq 0:6c56fb4bc5f0 517 {
nexpaq 0:6c56fb4bc5f0 518 if( acc[j] == 0 )
nexpaq 0:6c56fb4bc5f0 519 {
nexpaq 0:6c56fb4bc5f0 520 ret = 1;
nexpaq 0:6c56fb4bc5f0 521 goto cleanup;
nexpaq 0:6c56fb4bc5f0 522 }
nexpaq 0:6c56fb4bc5f0 523 }
nexpaq 0:6c56fb4bc5f0 524
nexpaq 0:6c56fb4bc5f0 525 cleanup:
nexpaq 0:6c56fb4bc5f0 526 mbedtls_entropy_free( &ctx );
nexpaq 0:6c56fb4bc5f0 527
nexpaq 0:6c56fb4bc5f0 528 if( verbose != 0 )
nexpaq 0:6c56fb4bc5f0 529 {
nexpaq 0:6c56fb4bc5f0 530 if( ret != 0 )
nexpaq 0:6c56fb4bc5f0 531 mbedtls_printf( "failed\n" );
nexpaq 0:6c56fb4bc5f0 532 else
nexpaq 0:6c56fb4bc5f0 533 mbedtls_printf( "passed\n" );
nexpaq 0:6c56fb4bc5f0 534
nexpaq 0:6c56fb4bc5f0 535 mbedtls_printf( "\n" );
nexpaq 0:6c56fb4bc5f0 536 }
nexpaq 0:6c56fb4bc5f0 537
nexpaq 0:6c56fb4bc5f0 538 return( ret != 0 );
nexpaq 0:6c56fb4bc5f0 539 }
nexpaq 0:6c56fb4bc5f0 540 #endif /* MBEDTLS_SELF_TEST */
nexpaq 0:6c56fb4bc5f0 541
nexpaq 0:6c56fb4bc5f0 542 #endif /* MBEDTLS_ENTROPY_C */