Austin Blackstone / Mbed 2 deprecated client-lwip-lightswitch-demo-expanded

mbed client lightswitch demo

Dependencies:   mbed Socket lwip-eth lwip-sys lwip

Fork of mbed-client-classic-example-lwip by Austin Blackstone

mbedtls/source/entropy.c@11:cada08fc8a70, 2016-06-09 (annotated)

Committer:
mbedAustin
Date:
Thu Jun 09 17:08:36 2016 +0000
Revision:
11:cada08fc8a70
Commit for public Consumption

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbedAustin 11:cada08fc8a70 1 /*
mbedAustin 11:cada08fc8a70 2 * Entropy accumulator implementation
mbedAustin 11:cada08fc8a70 3 *
mbedAustin 11:cada08fc8a70 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
mbedAustin 11:cada08fc8a70 5 * SPDX-License-Identifier: Apache-2.0
mbedAustin 11:cada08fc8a70 6 *
mbedAustin 11:cada08fc8a70 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
mbedAustin 11:cada08fc8a70 8 * not use this file except in compliance with the License.
mbedAustin 11:cada08fc8a70 9 * You may obtain a copy of the License at
mbedAustin 11:cada08fc8a70 10 *
mbedAustin 11:cada08fc8a70 11 * http://www.apache.org/licenses/LICENSE-2.0
mbedAustin 11:cada08fc8a70 12 *
mbedAustin 11:cada08fc8a70 13 * Unless required by applicable law or agreed to in writing, software
mbedAustin 11:cada08fc8a70 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
mbedAustin 11:cada08fc8a70 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbedAustin 11:cada08fc8a70 16 * See the License for the specific language governing permissions and
mbedAustin 11:cada08fc8a70 17 * limitations under the License.
mbedAustin 11:cada08fc8a70 18 *
mbedAustin 11:cada08fc8a70 19 * This file is part of mbed TLS (https://tls.mbed.org)
mbedAustin 11:cada08fc8a70 20 */
mbedAustin 11:cada08fc8a70 21
mbedAustin 11:cada08fc8a70 22 #if !defined(MBEDTLS_CONFIG_FILE)
mbedAustin 11:cada08fc8a70 23 #include "mbedtls/config.h"
mbedAustin 11:cada08fc8a70 24 #else
mbedAustin 11:cada08fc8a70 25 #include MBEDTLS_CONFIG_FILE
mbedAustin 11:cada08fc8a70 26 #endif
mbedAustin 11:cada08fc8a70 27
mbedAustin 11:cada08fc8a70 28 #if defined(MBEDTLS_ENTROPY_C)
mbedAustin 11:cada08fc8a70 29
mbedAustin 11:cada08fc8a70 30 #include "mbedtls/entropy.h"
mbedAustin 11:cada08fc8a70 31 #include "mbedtls/entropy_poll.h"
mbedAustin 11:cada08fc8a70 32
mbedAustin 11:cada08fc8a70 33 #include <string.h>
mbedAustin 11:cada08fc8a70 34
mbedAustin 11:cada08fc8a70 35 #if defined(MBEDTLS_FS_IO)
mbedAustin 11:cada08fc8a70 36 #include <stdio.h>
mbedAustin 11:cada08fc8a70 37 #endif
mbedAustin 11:cada08fc8a70 38
mbedAustin 11:cada08fc8a70 39 #if defined(MBEDTLS_SELF_TEST)
mbedAustin 11:cada08fc8a70 40 #if defined(MBEDTLS_PLATFORM_C)
mbedAustin 11:cada08fc8a70 41 #include "mbedtls/platform.h"
mbedAustin 11:cada08fc8a70 42 #else
mbedAustin 11:cada08fc8a70 43 #include <stdio.h>
mbedAustin 11:cada08fc8a70 44 #define mbedtls_printf printf
mbedAustin 11:cada08fc8a70 45 #endif /* MBEDTLS_PLATFORM_C */
mbedAustin 11:cada08fc8a70 46 #endif /* MBEDTLS_SELF_TEST */
mbedAustin 11:cada08fc8a70 47
mbedAustin 11:cada08fc8a70 48 #if defined(MBEDTLS_HAVEGE_C)
mbedAustin 11:cada08fc8a70 49 #include "mbedtls/havege.h"
mbedAustin 11:cada08fc8a70 50 #endif
mbedAustin 11:cada08fc8a70 51
mbedAustin 11:cada08fc8a70 52 /* Implementation that should never be optimized out by the compiler */
mbedAustin 11:cada08fc8a70 53 static void mbedtls_zeroize( void *v, size_t n ) {
mbedAustin 11:cada08fc8a70 54 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
mbedAustin 11:cada08fc8a70 55 }
mbedAustin 11:cada08fc8a70 56
mbedAustin 11:cada08fc8a70 57 #define ENTROPY_MAX_LOOP 256 /**< Maximum amount to loop before error */
mbedAustin 11:cada08fc8a70 58
mbedAustin 11:cada08fc8a70 59 void mbedtls_entropy_init( mbedtls_entropy_context *ctx )
mbedAustin 11:cada08fc8a70 60 {
mbedAustin 11:cada08fc8a70 61 memset( ctx, 0, sizeof(mbedtls_entropy_context) );
mbedAustin 11:cada08fc8a70 62
mbedAustin 11:cada08fc8a70 63 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 64 mbedtls_mutex_init( &ctx->mutex );
mbedAustin 11:cada08fc8a70 65 #endif
mbedAustin 11:cada08fc8a70 66
mbedAustin 11:cada08fc8a70 67 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedAustin 11:cada08fc8a70 68 mbedtls_sha512_starts( &ctx->accumulator, 0 );
mbedAustin 11:cada08fc8a70 69 #else
mbedAustin 11:cada08fc8a70 70 mbedtls_sha256_starts( &ctx->accumulator, 0 );
mbedAustin 11:cada08fc8a70 71 #endif
mbedAustin 11:cada08fc8a70 72 #if defined(MBEDTLS_HAVEGE_C)
mbedAustin 11:cada08fc8a70 73 mbedtls_havege_init( &ctx->havege_data );
mbedAustin 11:cada08fc8a70 74 #endif
mbedAustin 11:cada08fc8a70 75
mbedAustin 11:cada08fc8a70 76 #if !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
mbedAustin 11:cada08fc8a70 77 #if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
mbedAustin 11:cada08fc8a70 78 mbedtls_entropy_add_source( ctx, mbedtls_platform_entropy_poll, NULL,
mbedAustin 11:cada08fc8a70 79 MBEDTLS_ENTROPY_MIN_PLATFORM,
mbedAustin 11:cada08fc8a70 80 MBEDTLS_ENTROPY_SOURCE_STRONG );
mbedAustin 11:cada08fc8a70 81 #endif
mbedAustin 11:cada08fc8a70 82 #if defined(MBEDTLS_TIMING_C)
mbedAustin 11:cada08fc8a70 83 mbedtls_entropy_add_source( ctx, mbedtls_hardclock_poll, NULL,
mbedAustin 11:cada08fc8a70 84 MBEDTLS_ENTROPY_MIN_HARDCLOCK,
mbedAustin 11:cada08fc8a70 85 MBEDTLS_ENTROPY_SOURCE_WEAK );
mbedAustin 11:cada08fc8a70 86 #endif
mbedAustin 11:cada08fc8a70 87 #if defined(MBEDTLS_HAVEGE_C)
mbedAustin 11:cada08fc8a70 88 mbedtls_entropy_add_source( ctx, mbedtls_havege_poll, &ctx->havege_data,
mbedAustin 11:cada08fc8a70 89 MBEDTLS_ENTROPY_MIN_HAVEGE,
mbedAustin 11:cada08fc8a70 90 MBEDTLS_ENTROPY_SOURCE_STRONG );
mbedAustin 11:cada08fc8a70 91 #endif
mbedAustin 11:cada08fc8a70 92 #if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
mbedAustin 11:cada08fc8a70 93 mbedtls_entropy_add_source( ctx, mbedtls_hardware_poll, NULL,
mbedAustin 11:cada08fc8a70 94 MBEDTLS_ENTROPY_MIN_HARDWARE,
mbedAustin 11:cada08fc8a70 95 MBEDTLS_ENTROPY_SOURCE_STRONG );
mbedAustin 11:cada08fc8a70 96 #endif
mbedAustin 11:cada08fc8a70 97 #endif /* MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES */
mbedAustin 11:cada08fc8a70 98 }
mbedAustin 11:cada08fc8a70 99
mbedAustin 11:cada08fc8a70 100 void mbedtls_entropy_free( mbedtls_entropy_context *ctx )
mbedAustin 11:cada08fc8a70 101 {
mbedAustin 11:cada08fc8a70 102 #if defined(MBEDTLS_HAVEGE_C)
mbedAustin 11:cada08fc8a70 103 mbedtls_havege_free( &ctx->havege_data );
mbedAustin 11:cada08fc8a70 104 #endif
mbedAustin 11:cada08fc8a70 105 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 106 mbedtls_mutex_free( &ctx->mutex );
mbedAustin 11:cada08fc8a70 107 #endif
mbedAustin 11:cada08fc8a70 108 mbedtls_zeroize( ctx, sizeof( mbedtls_entropy_context ) );
mbedAustin 11:cada08fc8a70 109 }
mbedAustin 11:cada08fc8a70 110
mbedAustin 11:cada08fc8a70 111 int mbedtls_entropy_add_source( mbedtls_entropy_context *ctx,
mbedAustin 11:cada08fc8a70 112 mbedtls_entropy_f_source_ptr f_source, void *p_source,
mbedAustin 11:cada08fc8a70 113 size_t threshold, int strong )
mbedAustin 11:cada08fc8a70 114 {
mbedAustin 11:cada08fc8a70 115 int index, ret = 0;
mbedAustin 11:cada08fc8a70 116
mbedAustin 11:cada08fc8a70 117 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 118 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
mbedAustin 11:cada08fc8a70 119 return( ret );
mbedAustin 11:cada08fc8a70 120 #endif
mbedAustin 11:cada08fc8a70 121
mbedAustin 11:cada08fc8a70 122 index = ctx->source_count;
mbedAustin 11:cada08fc8a70 123 if( index >= MBEDTLS_ENTROPY_MAX_SOURCES )
mbedAustin 11:cada08fc8a70 124 {
mbedAustin 11:cada08fc8a70 125 ret = MBEDTLS_ERR_ENTROPY_MAX_SOURCES;
mbedAustin 11:cada08fc8a70 126 goto exit;
mbedAustin 11:cada08fc8a70 127 }
mbedAustin 11:cada08fc8a70 128
mbedAustin 11:cada08fc8a70 129 ctx->source[index].f_source = f_source;
mbedAustin 11:cada08fc8a70 130 ctx->source[index].p_source = p_source;
mbedAustin 11:cada08fc8a70 131 ctx->source[index].threshold = threshold;
mbedAustin 11:cada08fc8a70 132 ctx->source[index].strong = strong;
mbedAustin 11:cada08fc8a70 133
mbedAustin 11:cada08fc8a70 134 ctx->source_count++;
mbedAustin 11:cada08fc8a70 135
mbedAustin 11:cada08fc8a70 136 exit:
mbedAustin 11:cada08fc8a70 137 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 138 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
mbedAustin 11:cada08fc8a70 139 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
mbedAustin 11:cada08fc8a70 140 #endif
mbedAustin 11:cada08fc8a70 141
mbedAustin 11:cada08fc8a70 142 return( ret );
mbedAustin 11:cada08fc8a70 143 }
mbedAustin 11:cada08fc8a70 144
mbedAustin 11:cada08fc8a70 145 /*
mbedAustin 11:cada08fc8a70 146 * Entropy accumulator update
mbedAustin 11:cada08fc8a70 147 */
mbedAustin 11:cada08fc8a70 148 static int entropy_update( mbedtls_entropy_context *ctx, unsigned char source_id,
mbedAustin 11:cada08fc8a70 149 const unsigned char *data, size_t len )
mbedAustin 11:cada08fc8a70 150 {
mbedAustin 11:cada08fc8a70 151 unsigned char header[2];
mbedAustin 11:cada08fc8a70 152 unsigned char tmp[MBEDTLS_ENTROPY_BLOCK_SIZE];
mbedAustin 11:cada08fc8a70 153 size_t use_len = len;
mbedAustin 11:cada08fc8a70 154 const unsigned char *p = data;
mbedAustin 11:cada08fc8a70 155
mbedAustin 11:cada08fc8a70 156 if( use_len > MBEDTLS_ENTROPY_BLOCK_SIZE )
mbedAustin 11:cada08fc8a70 157 {
mbedAustin 11:cada08fc8a70 158 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedAustin 11:cada08fc8a70 159 mbedtls_sha512( data, len, tmp, 0 );
mbedAustin 11:cada08fc8a70 160 #else
mbedAustin 11:cada08fc8a70 161 mbedtls_sha256( data, len, tmp, 0 );
mbedAustin 11:cada08fc8a70 162 #endif
mbedAustin 11:cada08fc8a70 163 p = tmp;
mbedAustin 11:cada08fc8a70 164 use_len = MBEDTLS_ENTROPY_BLOCK_SIZE;
mbedAustin 11:cada08fc8a70 165 }
mbedAustin 11:cada08fc8a70 166
mbedAustin 11:cada08fc8a70 167 header[0] = source_id;
mbedAustin 11:cada08fc8a70 168 header[1] = use_len & 0xFF;
mbedAustin 11:cada08fc8a70 169
mbedAustin 11:cada08fc8a70 170 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedAustin 11:cada08fc8a70 171 mbedtls_sha512_update( &ctx->accumulator, header, 2 );
mbedAustin 11:cada08fc8a70 172 mbedtls_sha512_update( &ctx->accumulator, p, use_len );
mbedAustin 11:cada08fc8a70 173 #else
mbedAustin 11:cada08fc8a70 174 mbedtls_sha256_update( &ctx->accumulator, header, 2 );
mbedAustin 11:cada08fc8a70 175 mbedtls_sha256_update( &ctx->accumulator, p, use_len );
mbedAustin 11:cada08fc8a70 176 #endif
mbedAustin 11:cada08fc8a70 177
mbedAustin 11:cada08fc8a70 178 return( 0 );
mbedAustin 11:cada08fc8a70 179 }
mbedAustin 11:cada08fc8a70 180
mbedAustin 11:cada08fc8a70 181 int mbedtls_entropy_update_manual( mbedtls_entropy_context *ctx,
mbedAustin 11:cada08fc8a70 182 const unsigned char *data, size_t len )
mbedAustin 11:cada08fc8a70 183 {
mbedAustin 11:cada08fc8a70 184 int ret;
mbedAustin 11:cada08fc8a70 185
mbedAustin 11:cada08fc8a70 186 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 187 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
mbedAustin 11:cada08fc8a70 188 return( ret );
mbedAustin 11:cada08fc8a70 189 #endif
mbedAustin 11:cada08fc8a70 190
mbedAustin 11:cada08fc8a70 191 ret = entropy_update( ctx, MBEDTLS_ENTROPY_SOURCE_MANUAL, data, len );
mbedAustin 11:cada08fc8a70 192
mbedAustin 11:cada08fc8a70 193 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 194 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
mbedAustin 11:cada08fc8a70 195 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
mbedAustin 11:cada08fc8a70 196 #endif
mbedAustin 11:cada08fc8a70 197
mbedAustin 11:cada08fc8a70 198 return( ret );
mbedAustin 11:cada08fc8a70 199 }
mbedAustin 11:cada08fc8a70 200
mbedAustin 11:cada08fc8a70 201 /*
mbedAustin 11:cada08fc8a70 202 * Run through the different sources to add entropy to our accumulator
mbedAustin 11:cada08fc8a70 203 */
mbedAustin 11:cada08fc8a70 204 static int entropy_gather_internal( mbedtls_entropy_context *ctx )
mbedAustin 11:cada08fc8a70 205 {
mbedAustin 11:cada08fc8a70 206 int ret, i, have_one_strong = 0;
mbedAustin 11:cada08fc8a70 207 unsigned char buf[MBEDTLS_ENTROPY_MAX_GATHER];
mbedAustin 11:cada08fc8a70 208 size_t olen;
mbedAustin 11:cada08fc8a70 209
mbedAustin 11:cada08fc8a70 210 if( ctx->source_count == 0 )
mbedAustin 11:cada08fc8a70 211 return( MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED );
mbedAustin 11:cada08fc8a70 212
mbedAustin 11:cada08fc8a70 213 /*
mbedAustin 11:cada08fc8a70 214 * Run through our entropy sources
mbedAustin 11:cada08fc8a70 215 */
mbedAustin 11:cada08fc8a70 216 for( i = 0; i < ctx->source_count; i++ )
mbedAustin 11:cada08fc8a70 217 {
mbedAustin 11:cada08fc8a70 218 if( ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG )
mbedAustin 11:cada08fc8a70 219 have_one_strong = 1;
mbedAustin 11:cada08fc8a70 220
mbedAustin 11:cada08fc8a70 221 olen = 0;
mbedAustin 11:cada08fc8a70 222 if( ( ret = ctx->source[i].f_source( ctx->source[i].p_source,
mbedAustin 11:cada08fc8a70 223 buf, MBEDTLS_ENTROPY_MAX_GATHER, &olen ) ) != 0 )
mbedAustin 11:cada08fc8a70 224 {
mbedAustin 11:cada08fc8a70 225 return( ret );
mbedAustin 11:cada08fc8a70 226 }
mbedAustin 11:cada08fc8a70 227
mbedAustin 11:cada08fc8a70 228 /*
mbedAustin 11:cada08fc8a70 229 * Add if we actually gathered something
mbedAustin 11:cada08fc8a70 230 */
mbedAustin 11:cada08fc8a70 231 if( olen > 0 )
mbedAustin 11:cada08fc8a70 232 {
mbedAustin 11:cada08fc8a70 233 entropy_update( ctx, (unsigned char) i, buf, olen );
mbedAustin 11:cada08fc8a70 234 ctx->source[i].size += olen;
mbedAustin 11:cada08fc8a70 235 }
mbedAustin 11:cada08fc8a70 236 }
mbedAustin 11:cada08fc8a70 237
mbedAustin 11:cada08fc8a70 238 if( have_one_strong == 0 )
mbedAustin 11:cada08fc8a70 239 return( MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE );
mbedAustin 11:cada08fc8a70 240
mbedAustin 11:cada08fc8a70 241 return( 0 );
mbedAustin 11:cada08fc8a70 242 }
mbedAustin 11:cada08fc8a70 243
mbedAustin 11:cada08fc8a70 244 /*
mbedAustin 11:cada08fc8a70 245 * Thread-safe wrapper for entropy_gather_internal()
mbedAustin 11:cada08fc8a70 246 */
mbedAustin 11:cada08fc8a70 247 int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
mbedAustin 11:cada08fc8a70 248 {
mbedAustin 11:cada08fc8a70 249 int ret;
mbedAustin 11:cada08fc8a70 250
mbedAustin 11:cada08fc8a70 251 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 252 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
mbedAustin 11:cada08fc8a70 253 return( ret );
mbedAustin 11:cada08fc8a70 254 #endif
mbedAustin 11:cada08fc8a70 255
mbedAustin 11:cada08fc8a70 256 ret = entropy_gather_internal( ctx );
mbedAustin 11:cada08fc8a70 257
mbedAustin 11:cada08fc8a70 258 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 259 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
mbedAustin 11:cada08fc8a70 260 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
mbedAustin 11:cada08fc8a70 261 #endif
mbedAustin 11:cada08fc8a70 262
mbedAustin 11:cada08fc8a70 263 return( ret );
mbedAustin 11:cada08fc8a70 264 }
mbedAustin 11:cada08fc8a70 265
mbedAustin 11:cada08fc8a70 266 int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
mbedAustin 11:cada08fc8a70 267 {
mbedAustin 11:cada08fc8a70 268 int ret, count = 0, i, done;
mbedAustin 11:cada08fc8a70 269 mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
mbedAustin 11:cada08fc8a70 270 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
mbedAustin 11:cada08fc8a70 271
mbedAustin 11:cada08fc8a70 272 if( len > MBEDTLS_ENTROPY_BLOCK_SIZE )
mbedAustin 11:cada08fc8a70 273 return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
mbedAustin 11:cada08fc8a70 274
mbedAustin 11:cada08fc8a70 275 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 276 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
mbedAustin 11:cada08fc8a70 277 return( ret );
mbedAustin 11:cada08fc8a70 278 #endif
mbedAustin 11:cada08fc8a70 279
mbedAustin 11:cada08fc8a70 280 /*
mbedAustin 11:cada08fc8a70 281 * Always gather extra entropy before a call
mbedAustin 11:cada08fc8a70 282 */
mbedAustin 11:cada08fc8a70 283 do
mbedAustin 11:cada08fc8a70 284 {
mbedAustin 11:cada08fc8a70 285 if( count++ > ENTROPY_MAX_LOOP )
mbedAustin 11:cada08fc8a70 286 {
mbedAustin 11:cada08fc8a70 287 ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
mbedAustin 11:cada08fc8a70 288 goto exit;
mbedAustin 11:cada08fc8a70 289 }
mbedAustin 11:cada08fc8a70 290
mbedAustin 11:cada08fc8a70 291 if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
mbedAustin 11:cada08fc8a70 292 goto exit;
mbedAustin 11:cada08fc8a70 293
mbedAustin 11:cada08fc8a70 294 done = 1;
mbedAustin 11:cada08fc8a70 295 for( i = 0; i < ctx->source_count; i++ )
mbedAustin 11:cada08fc8a70 296 if( ctx->source[i].size < ctx->source[i].threshold )
mbedAustin 11:cada08fc8a70 297 done = 0;
mbedAustin 11:cada08fc8a70 298 }
mbedAustin 11:cada08fc8a70 299 while( ! done );
mbedAustin 11:cada08fc8a70 300
mbedAustin 11:cada08fc8a70 301 memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
mbedAustin 11:cada08fc8a70 302
mbedAustin 11:cada08fc8a70 303 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
mbedAustin 11:cada08fc8a70 304 mbedtls_sha512_finish( &ctx->accumulator, buf );
mbedAustin 11:cada08fc8a70 305
mbedAustin 11:cada08fc8a70 306 /*
mbedAustin 11:cada08fc8a70 307 * Reset accumulator and counters and recycle existing entropy
mbedAustin 11:cada08fc8a70 308 */
mbedAustin 11:cada08fc8a70 309 memset( &ctx->accumulator, 0, sizeof( mbedtls_sha512_context ) );
mbedAustin 11:cada08fc8a70 310 mbedtls_sha512_starts( &ctx->accumulator, 0 );
mbedAustin 11:cada08fc8a70 311 mbedtls_sha512_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
mbedAustin 11:cada08fc8a70 312
mbedAustin 11:cada08fc8a70 313 /*
mbedAustin 11:cada08fc8a70 314 * Perform second SHA-512 on entropy
mbedAustin 11:cada08fc8a70 315 */
mbedAustin 11:cada08fc8a70 316 mbedtls_sha512( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
mbedAustin 11:cada08fc8a70 317 #else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
mbedAustin 11:cada08fc8a70 318 mbedtls_sha256_finish( &ctx->accumulator, buf );
mbedAustin 11:cada08fc8a70 319
mbedAustin 11:cada08fc8a70 320 /*
mbedAustin 11:cada08fc8a70 321 * Reset accumulator and counters and recycle existing entropy
mbedAustin 11:cada08fc8a70 322 */
mbedAustin 11:cada08fc8a70 323 memset( &ctx->accumulator, 0, sizeof( mbedtls_sha256_context ) );
mbedAustin 11:cada08fc8a70 324 mbedtls_sha256_starts( &ctx->accumulator, 0 );
mbedAustin 11:cada08fc8a70 325 mbedtls_sha256_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
mbedAustin 11:cada08fc8a70 326
mbedAustin 11:cada08fc8a70 327 /*
mbedAustin 11:cada08fc8a70 328 * Perform second SHA-256 on entropy
mbedAustin 11:cada08fc8a70 329 */
mbedAustin 11:cada08fc8a70 330 mbedtls_sha256( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
mbedAustin 11:cada08fc8a70 331 #endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
mbedAustin 11:cada08fc8a70 332
mbedAustin 11:cada08fc8a70 333 for( i = 0; i < ctx->source_count; i++ )
mbedAustin 11:cada08fc8a70 334 ctx->source[i].size = 0;
mbedAustin 11:cada08fc8a70 335
mbedAustin 11:cada08fc8a70 336 memcpy( output, buf, len );
mbedAustin 11:cada08fc8a70 337
mbedAustin 11:cada08fc8a70 338 ret = 0;
mbedAustin 11:cada08fc8a70 339
mbedAustin 11:cada08fc8a70 340 exit:
mbedAustin 11:cada08fc8a70 341 #if defined(MBEDTLS_THREADING_C)
mbedAustin 11:cada08fc8a70 342 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
mbedAustin 11:cada08fc8a70 343 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
mbedAustin 11:cada08fc8a70 344 #endif
mbedAustin 11:cada08fc8a70 345
mbedAustin 11:cada08fc8a70 346 return( ret );
mbedAustin 11:cada08fc8a70 347 }
mbedAustin 11:cada08fc8a70 348
mbedAustin 11:cada08fc8a70 349 #if defined(MBEDTLS_FS_IO)
mbedAustin 11:cada08fc8a70 350 int mbedtls_entropy_write_seed_file( mbedtls_entropy_context *ctx, const char *path )
mbedAustin 11:cada08fc8a70 351 {
mbedAustin 11:cada08fc8a70 352 int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
mbedAustin 11:cada08fc8a70 353 FILE *f;
mbedAustin 11:cada08fc8a70 354 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
mbedAustin 11:cada08fc8a70 355
mbedAustin 11:cada08fc8a70 356 if( ( f = fopen( path, "wb" ) ) == NULL )
mbedAustin 11:cada08fc8a70 357 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
mbedAustin 11:cada08fc8a70 358
mbedAustin 11:cada08fc8a70 359 if( ( ret = mbedtls_entropy_func( ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
mbedAustin 11:cada08fc8a70 360 goto exit;
mbedAustin 11:cada08fc8a70 361
mbedAustin 11:cada08fc8a70 362 if( fwrite( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) != MBEDTLS_ENTROPY_BLOCK_SIZE )
mbedAustin 11:cada08fc8a70 363 {
mbedAustin 11:cada08fc8a70 364 ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
mbedAustin 11:cada08fc8a70 365 goto exit;
mbedAustin 11:cada08fc8a70 366 }
mbedAustin 11:cada08fc8a70 367
mbedAustin 11:cada08fc8a70 368 ret = 0;
mbedAustin 11:cada08fc8a70 369
mbedAustin 11:cada08fc8a70 370 exit:
mbedAustin 11:cada08fc8a70 371 fclose( f );
mbedAustin 11:cada08fc8a70 372 return( ret );
mbedAustin 11:cada08fc8a70 373 }
mbedAustin 11:cada08fc8a70 374
mbedAustin 11:cada08fc8a70 375 int mbedtls_entropy_update_seed_file( mbedtls_entropy_context *ctx, const char *path )
mbedAustin 11:cada08fc8a70 376 {
mbedAustin 11:cada08fc8a70 377 FILE *f;
mbedAustin 11:cada08fc8a70 378 size_t n;
mbedAustin 11:cada08fc8a70 379 unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
mbedAustin 11:cada08fc8a70 380
mbedAustin 11:cada08fc8a70 381 if( ( f = fopen( path, "rb" ) ) == NULL )
mbedAustin 11:cada08fc8a70 382 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
mbedAustin 11:cada08fc8a70 383
mbedAustin 11:cada08fc8a70 384 fseek( f, 0, SEEK_END );
mbedAustin 11:cada08fc8a70 385 n = (size_t) ftell( f );
mbedAustin 11:cada08fc8a70 386 fseek( f, 0, SEEK_SET );
mbedAustin 11:cada08fc8a70 387
mbedAustin 11:cada08fc8a70 388 if( n > MBEDTLS_ENTROPY_MAX_SEED_SIZE )
mbedAustin 11:cada08fc8a70 389 n = MBEDTLS_ENTROPY_MAX_SEED_SIZE;
mbedAustin 11:cada08fc8a70 390
mbedAustin 11:cada08fc8a70 391 if( fread( buf, 1, n, f ) != n )
mbedAustin 11:cada08fc8a70 392 {
mbedAustin 11:cada08fc8a70 393 fclose( f );
mbedAustin 11:cada08fc8a70 394 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
mbedAustin 11:cada08fc8a70 395 }
mbedAustin 11:cada08fc8a70 396
mbedAustin 11:cada08fc8a70 397 fclose( f );
mbedAustin 11:cada08fc8a70 398
mbedAustin 11:cada08fc8a70 399 mbedtls_entropy_update_manual( ctx, buf, n );
mbedAustin 11:cada08fc8a70 400
mbedAustin 11:cada08fc8a70 401 return( mbedtls_entropy_write_seed_file( ctx, path ) );
mbedAustin 11:cada08fc8a70 402 }
mbedAustin 11:cada08fc8a70 403 #endif /* MBEDTLS_FS_IO */
mbedAustin 11:cada08fc8a70 404
mbedAustin 11:cada08fc8a70 405 #if defined(MBEDTLS_SELF_TEST)
mbedAustin 11:cada08fc8a70 406 /*
mbedAustin 11:cada08fc8a70 407 * Dummy source function
mbedAustin 11:cada08fc8a70 408 */
mbedAustin 11:cada08fc8a70 409 static int entropy_dummy_source( void *data, unsigned char *output,
mbedAustin 11:cada08fc8a70 410 size_t len, size_t *olen )
mbedAustin 11:cada08fc8a70 411 {
mbedAustin 11:cada08fc8a70 412 ((void) data);
mbedAustin 11:cada08fc8a70 413
mbedAustin 11:cada08fc8a70 414 memset( output, 0x2a, len );
mbedAustin 11:cada08fc8a70 415 *olen = len;
mbedAustin 11:cada08fc8a70 416
mbedAustin 11:cada08fc8a70 417 return( 0 );
mbedAustin 11:cada08fc8a70 418 }
mbedAustin 11:cada08fc8a70 419
mbedAustin 11:cada08fc8a70 420 /*
mbedAustin 11:cada08fc8a70 421 * The actual entropy quality is hard to test, but we can at least
mbedAustin 11:cada08fc8a70 422 * test that the functions don't cause errors and write the correct
mbedAustin 11:cada08fc8a70 423 * amount of data to buffers.
mbedAustin 11:cada08fc8a70 424 */
mbedAustin 11:cada08fc8a70 425 int mbedtls_entropy_self_test( int verbose )
mbedAustin 11:cada08fc8a70 426 {
mbedAustin 11:cada08fc8a70 427 int ret = 0;
mbedAustin 11:cada08fc8a70 428 mbedtls_entropy_context ctx;
mbedAustin 11:cada08fc8a70 429 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
mbedAustin 11:cada08fc8a70 430 unsigned char acc[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
mbedAustin 11:cada08fc8a70 431 size_t i, j;
mbedAustin 11:cada08fc8a70 432
mbedAustin 11:cada08fc8a70 433 if( verbose != 0 )
mbedAustin 11:cada08fc8a70 434 mbedtls_printf( " ENTROPY test: " );
mbedAustin 11:cada08fc8a70 435
mbedAustin 11:cada08fc8a70 436 mbedtls_entropy_init( &ctx );
mbedAustin 11:cada08fc8a70 437
mbedAustin 11:cada08fc8a70 438 /* First do a gather to make sure we have default sources */
mbedAustin 11:cada08fc8a70 439 if( ( ret = mbedtls_entropy_gather( &ctx ) ) != 0 )
mbedAustin 11:cada08fc8a70 440 goto cleanup;
mbedAustin 11:cada08fc8a70 441
mbedAustin 11:cada08fc8a70 442 ret = mbedtls_entropy_add_source( &ctx, entropy_dummy_source, NULL, 16,
mbedAustin 11:cada08fc8a70 443 MBEDTLS_ENTROPY_SOURCE_WEAK );
mbedAustin 11:cada08fc8a70 444 if( ret != 0 )
mbedAustin 11:cada08fc8a70 445 goto cleanup;
mbedAustin 11:cada08fc8a70 446
mbedAustin 11:cada08fc8a70 447 if( ( ret = mbedtls_entropy_update_manual( &ctx, buf, sizeof buf ) ) != 0 )
mbedAustin 11:cada08fc8a70 448 goto cleanup;
mbedAustin 11:cada08fc8a70 449
mbedAustin 11:cada08fc8a70 450 /*
mbedAustin 11:cada08fc8a70 451 * To test that mbedtls_entropy_func writes correct number of bytes:
mbedAustin 11:cada08fc8a70 452 * - use the whole buffer and rely on ASan to detect overruns
mbedAustin 11:cada08fc8a70 453 * - collect entropy 8 times and OR the result in an accumulator:
mbedAustin 11:cada08fc8a70 454 * any byte should then be 0 with probably 2^(-64), so requiring
mbedAustin 11:cada08fc8a70 455 * each of the 32 or 64 bytes to be non-zero has a false failure rate
mbedAustin 11:cada08fc8a70 456 * of at most 2^(-58) which is acceptable.
mbedAustin 11:cada08fc8a70 457 */
mbedAustin 11:cada08fc8a70 458 for( i = 0; i < 8; i++ )
mbedAustin 11:cada08fc8a70 459 {
mbedAustin 11:cada08fc8a70 460 if( ( ret = mbedtls_entropy_func( &ctx, buf, sizeof( buf ) ) ) != 0 )
mbedAustin 11:cada08fc8a70 461 goto cleanup;
mbedAustin 11:cada08fc8a70 462
mbedAustin 11:cada08fc8a70 463 for( j = 0; j < sizeof( buf ); j++ )
mbedAustin 11:cada08fc8a70 464 acc[j] |= buf[j];
mbedAustin 11:cada08fc8a70 465 }
mbedAustin 11:cada08fc8a70 466
mbedAustin 11:cada08fc8a70 467 for( j = 0; j < sizeof( buf ); j++ )
mbedAustin 11:cada08fc8a70 468 {
mbedAustin 11:cada08fc8a70 469 if( acc[j] == 0 )
mbedAustin 11:cada08fc8a70 470 {
mbedAustin 11:cada08fc8a70 471 ret = 1;
mbedAustin 11:cada08fc8a70 472 goto cleanup;
mbedAustin 11:cada08fc8a70 473 }
mbedAustin 11:cada08fc8a70 474 }
mbedAustin 11:cada08fc8a70 475
mbedAustin 11:cada08fc8a70 476 cleanup:
mbedAustin 11:cada08fc8a70 477 mbedtls_entropy_free( &ctx );
mbedAustin 11:cada08fc8a70 478
mbedAustin 11:cada08fc8a70 479 if( verbose != 0 )
mbedAustin 11:cada08fc8a70 480 {
mbedAustin 11:cada08fc8a70 481 if( ret != 0 )
mbedAustin 11:cada08fc8a70 482 mbedtls_printf( "failed\n" );
mbedAustin 11:cada08fc8a70 483 else
mbedAustin 11:cada08fc8a70 484 mbedtls_printf( "passed\n" );
mbedAustin 11:cada08fc8a70 485
mbedAustin 11:cada08fc8a70 486 mbedtls_printf( "\n" );
mbedAustin 11:cada08fc8a70 487 }
mbedAustin 11:cada08fc8a70 488
mbedAustin 11:cada08fc8a70 489 return( ret != 0 );
mbedAustin 11:cada08fc8a70 490 }
mbedAustin 11:cada08fc8a70 491 #endif /* MBEDTLS_SELF_TEST */
mbedAustin 11:cada08fc8a70 492
mbedAustin 11:cada08fc8a70 493 #endif /* MBEDTLS_ENTROPY_C */