Timothy Beight / Mbed 2 deprecated 6_songs-from-the-cloud

This is a fork due to permission issues

Dependencies:   mbed Socket lwip-eth lwip-sys lwip

Fork of 6_songs-from-the-cloud by MakingMusicWorkshop

mbed-client/mbedtls/source/entropy.c@1:0ddbe2d3319c, 2016-05-19 (annotated)

Committer:
timbeight
Date:
Thu May 19 16:02:10 2016 +0000
Revision:
1:0ddbe2d3319c
Parent:
0:f7c60d3e7b8a 
This is my first commit while in the class.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
maclobdell 0:f7c60d3e7b8a 1 /*
maclobdell 0:f7c60d3e7b8a 2 * Entropy accumulator implementation
maclobdell 0:f7c60d3e7b8a 3 *
maclobdell 0:f7c60d3e7b8a 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
maclobdell 0:f7c60d3e7b8a 5 * SPDX-License-Identifier: Apache-2.0
maclobdell 0:f7c60d3e7b8a 6 *
maclobdell 0:f7c60d3e7b8a 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
maclobdell 0:f7c60d3e7b8a 8 * not use this file except in compliance with the License.
maclobdell 0:f7c60d3e7b8a 9 * You may obtain a copy of the License at
maclobdell 0:f7c60d3e7b8a 10 *
maclobdell 0:f7c60d3e7b8a 11 * http://www.apache.org/licenses/LICENSE-2.0
maclobdell 0:f7c60d3e7b8a 12 *
maclobdell 0:f7c60d3e7b8a 13 * Unless required by applicable law or agreed to in writing, software
maclobdell 0:f7c60d3e7b8a 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
maclobdell 0:f7c60d3e7b8a 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
maclobdell 0:f7c60d3e7b8a 16 * See the License for the specific language governing permissions and
maclobdell 0:f7c60d3e7b8a 17 * limitations under the License.
maclobdell 0:f7c60d3e7b8a 18 *
maclobdell 0:f7c60d3e7b8a 19 * This file is part of mbed TLS (https://tls.mbed.org)
maclobdell 0:f7c60d3e7b8a 20 */
maclobdell 0:f7c60d3e7b8a 21
maclobdell 0:f7c60d3e7b8a 22 #if !defined(MBEDTLS_CONFIG_FILE)
maclobdell 0:f7c60d3e7b8a 23 #include "mbedtls/config.h"
maclobdell 0:f7c60d3e7b8a 24 #else
maclobdell 0:f7c60d3e7b8a 25 #include MBEDTLS_CONFIG_FILE
maclobdell 0:f7c60d3e7b8a 26 #endif
maclobdell 0:f7c60d3e7b8a 27
maclobdell 0:f7c60d3e7b8a 28 #if defined(MBEDTLS_ENTROPY_C)
maclobdell 0:f7c60d3e7b8a 29
maclobdell 0:f7c60d3e7b8a 30 #include "mbedtls/entropy.h"
maclobdell 0:f7c60d3e7b8a 31 #include "mbedtls/entropy_poll.h"
maclobdell 0:f7c60d3e7b8a 32
maclobdell 0:f7c60d3e7b8a 33 #include <string.h>
maclobdell 0:f7c60d3e7b8a 34
maclobdell 0:f7c60d3e7b8a 35 #if defined(MBEDTLS_FS_IO)
maclobdell 0:f7c60d3e7b8a 36 #include <stdio.h>
maclobdell 0:f7c60d3e7b8a 37 #endif
maclobdell 0:f7c60d3e7b8a 38
maclobdell 0:f7c60d3e7b8a 39 #if defined(MBEDTLS_SELF_TEST)
maclobdell 0:f7c60d3e7b8a 40 #if defined(MBEDTLS_PLATFORM_C)
maclobdell 0:f7c60d3e7b8a 41 #include "mbedtls/platform.h"
maclobdell 0:f7c60d3e7b8a 42 #else
maclobdell 0:f7c60d3e7b8a 43 #include <stdio.h>
maclobdell 0:f7c60d3e7b8a 44 #define mbedtls_printf printf
maclobdell 0:f7c60d3e7b8a 45 #endif /* MBEDTLS_PLATFORM_C */
maclobdell 0:f7c60d3e7b8a 46 #endif /* MBEDTLS_SELF_TEST */
maclobdell 0:f7c60d3e7b8a 47
maclobdell 0:f7c60d3e7b8a 48 #if defined(MBEDTLS_HAVEGE_C)
maclobdell 0:f7c60d3e7b8a 49 #include "mbedtls/havege.h"
maclobdell 0:f7c60d3e7b8a 50 #endif
maclobdell 0:f7c60d3e7b8a 51
maclobdell 0:f7c60d3e7b8a 52 /* Implementation that should never be optimized out by the compiler */
maclobdell 0:f7c60d3e7b8a 53 static void mbedtls_zeroize( void *v, size_t n ) {
maclobdell 0:f7c60d3e7b8a 54 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
maclobdell 0:f7c60d3e7b8a 55 }
maclobdell 0:f7c60d3e7b8a 56
maclobdell 0:f7c60d3e7b8a 57 #define ENTROPY_MAX_LOOP 256 /**< Maximum amount to loop before error */
maclobdell 0:f7c60d3e7b8a 58
maclobdell 0:f7c60d3e7b8a 59 void mbedtls_entropy_init( mbedtls_entropy_context *ctx )
maclobdell 0:f7c60d3e7b8a 60 {
maclobdell 0:f7c60d3e7b8a 61 memset( ctx, 0, sizeof(mbedtls_entropy_context) );
maclobdell 0:f7c60d3e7b8a 62
maclobdell 0:f7c60d3e7b8a 63 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 64 mbedtls_mutex_init( &ctx->mutex );
maclobdell 0:f7c60d3e7b8a 65 #endif
maclobdell 0:f7c60d3e7b8a 66
maclobdell 0:f7c60d3e7b8a 67 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
maclobdell 0:f7c60d3e7b8a 68 mbedtls_sha512_starts( &ctx->accumulator, 0 );
maclobdell 0:f7c60d3e7b8a 69 #else
maclobdell 0:f7c60d3e7b8a 70 mbedtls_sha256_starts( &ctx->accumulator, 0 );
maclobdell 0:f7c60d3e7b8a 71 #endif
maclobdell 0:f7c60d3e7b8a 72 #if defined(MBEDTLS_HAVEGE_C)
maclobdell 0:f7c60d3e7b8a 73 mbedtls_havege_init( &ctx->havege_data );
maclobdell 0:f7c60d3e7b8a 74 #endif
maclobdell 0:f7c60d3e7b8a 75
maclobdell 0:f7c60d3e7b8a 76 #if !defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
maclobdell 0:f7c60d3e7b8a 77 #if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
maclobdell 0:f7c60d3e7b8a 78 mbedtls_entropy_add_source( ctx, mbedtls_platform_entropy_poll, NULL,
maclobdell 0:f7c60d3e7b8a 79 MBEDTLS_ENTROPY_MIN_PLATFORM,
maclobdell 0:f7c60d3e7b8a 80 MBEDTLS_ENTROPY_SOURCE_STRONG );
maclobdell 0:f7c60d3e7b8a 81 #endif
maclobdell 0:f7c60d3e7b8a 82 #if defined(MBEDTLS_TIMING_C)
maclobdell 0:f7c60d3e7b8a 83 mbedtls_entropy_add_source( ctx, mbedtls_hardclock_poll, NULL,
maclobdell 0:f7c60d3e7b8a 84 MBEDTLS_ENTROPY_MIN_HARDCLOCK,
maclobdell 0:f7c60d3e7b8a 85 MBEDTLS_ENTROPY_SOURCE_WEAK );
maclobdell 0:f7c60d3e7b8a 86 #endif
maclobdell 0:f7c60d3e7b8a 87 #if defined(MBEDTLS_HAVEGE_C)
maclobdell 0:f7c60d3e7b8a 88 mbedtls_entropy_add_source( ctx, mbedtls_havege_poll, &ctx->havege_data,
maclobdell 0:f7c60d3e7b8a 89 MBEDTLS_ENTROPY_MIN_HAVEGE,
maclobdell 0:f7c60d3e7b8a 90 MBEDTLS_ENTROPY_SOURCE_STRONG );
maclobdell 0:f7c60d3e7b8a 91 #endif
maclobdell 0:f7c60d3e7b8a 92 #if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
maclobdell 0:f7c60d3e7b8a 93 mbedtls_entropy_add_source( ctx, mbedtls_hardware_poll, NULL,
maclobdell 0:f7c60d3e7b8a 94 MBEDTLS_ENTROPY_MIN_HARDWARE,
maclobdell 0:f7c60d3e7b8a 95 MBEDTLS_ENTROPY_SOURCE_STRONG );
maclobdell 0:f7c60d3e7b8a 96 #endif
maclobdell 0:f7c60d3e7b8a 97 #endif /* MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES */
maclobdell 0:f7c60d3e7b8a 98 }
maclobdell 0:f7c60d3e7b8a 99
maclobdell 0:f7c60d3e7b8a 100 void mbedtls_entropy_free( mbedtls_entropy_context *ctx )
maclobdell 0:f7c60d3e7b8a 101 {
maclobdell 0:f7c60d3e7b8a 102 #if defined(MBEDTLS_HAVEGE_C)
maclobdell 0:f7c60d3e7b8a 103 mbedtls_havege_free( &ctx->havege_data );
maclobdell 0:f7c60d3e7b8a 104 #endif
maclobdell 0:f7c60d3e7b8a 105 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 106 mbedtls_mutex_free( &ctx->mutex );
maclobdell 0:f7c60d3e7b8a 107 #endif
maclobdell 0:f7c60d3e7b8a 108 mbedtls_zeroize( ctx, sizeof( mbedtls_entropy_context ) );
maclobdell 0:f7c60d3e7b8a 109 }
maclobdell 0:f7c60d3e7b8a 110
maclobdell 0:f7c60d3e7b8a 111 int mbedtls_entropy_add_source( mbedtls_entropy_context *ctx,
maclobdell 0:f7c60d3e7b8a 112 mbedtls_entropy_f_source_ptr f_source, void *p_source,
maclobdell 0:f7c60d3e7b8a 113 size_t threshold, int strong )
maclobdell 0:f7c60d3e7b8a 114 {
maclobdell 0:f7c60d3e7b8a 115 int index, ret = 0;
maclobdell 0:f7c60d3e7b8a 116
maclobdell 0:f7c60d3e7b8a 117 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 118 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 119 return( ret );
maclobdell 0:f7c60d3e7b8a 120 #endif
maclobdell 0:f7c60d3e7b8a 121
maclobdell 0:f7c60d3e7b8a 122 index = ctx->source_count;
maclobdell 0:f7c60d3e7b8a 123 if( index >= MBEDTLS_ENTROPY_MAX_SOURCES )
maclobdell 0:f7c60d3e7b8a 124 {
maclobdell 0:f7c60d3e7b8a 125 ret = MBEDTLS_ERR_ENTROPY_MAX_SOURCES;
maclobdell 0:f7c60d3e7b8a 126 goto exit;
maclobdell 0:f7c60d3e7b8a 127 }
maclobdell 0:f7c60d3e7b8a 128
maclobdell 0:f7c60d3e7b8a 129 ctx->source[index].f_source = f_source;
maclobdell 0:f7c60d3e7b8a 130 ctx->source[index].p_source = p_source;
maclobdell 0:f7c60d3e7b8a 131 ctx->source[index].threshold = threshold;
maclobdell 0:f7c60d3e7b8a 132 ctx->source[index].strong = strong;
maclobdell 0:f7c60d3e7b8a 133
maclobdell 0:f7c60d3e7b8a 134 ctx->source_count++;
maclobdell 0:f7c60d3e7b8a 135
maclobdell 0:f7c60d3e7b8a 136 exit:
maclobdell 0:f7c60d3e7b8a 137 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 138 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
maclobdell 0:f7c60d3e7b8a 139 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
maclobdell 0:f7c60d3e7b8a 140 #endif
maclobdell 0:f7c60d3e7b8a 141
maclobdell 0:f7c60d3e7b8a 142 return( ret );
maclobdell 0:f7c60d3e7b8a 143 }
maclobdell 0:f7c60d3e7b8a 144
maclobdell 0:f7c60d3e7b8a 145 /*
maclobdell 0:f7c60d3e7b8a 146 * Entropy accumulator update
maclobdell 0:f7c60d3e7b8a 147 */
maclobdell 0:f7c60d3e7b8a 148 static int entropy_update( mbedtls_entropy_context *ctx, unsigned char source_id,
maclobdell 0:f7c60d3e7b8a 149 const unsigned char *data, size_t len )
maclobdell 0:f7c60d3e7b8a 150 {
maclobdell 0:f7c60d3e7b8a 151 unsigned char header[2];
maclobdell 0:f7c60d3e7b8a 152 unsigned char tmp[MBEDTLS_ENTROPY_BLOCK_SIZE];
maclobdell 0:f7c60d3e7b8a 153 size_t use_len = len;
maclobdell 0:f7c60d3e7b8a 154 const unsigned char *p = data;
maclobdell 0:f7c60d3e7b8a 155
maclobdell 0:f7c60d3e7b8a 156 if( use_len > MBEDTLS_ENTROPY_BLOCK_SIZE )
maclobdell 0:f7c60d3e7b8a 157 {
maclobdell 0:f7c60d3e7b8a 158 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
maclobdell 0:f7c60d3e7b8a 159 mbedtls_sha512( data, len, tmp, 0 );
maclobdell 0:f7c60d3e7b8a 160 #else
maclobdell 0:f7c60d3e7b8a 161 mbedtls_sha256( data, len, tmp, 0 );
maclobdell 0:f7c60d3e7b8a 162 #endif
maclobdell 0:f7c60d3e7b8a 163 p = tmp;
maclobdell 0:f7c60d3e7b8a 164 use_len = MBEDTLS_ENTROPY_BLOCK_SIZE;
maclobdell 0:f7c60d3e7b8a 165 }
maclobdell 0:f7c60d3e7b8a 166
maclobdell 0:f7c60d3e7b8a 167 header[0] = source_id;
maclobdell 0:f7c60d3e7b8a 168 header[1] = use_len & 0xFF;
maclobdell 0:f7c60d3e7b8a 169
maclobdell 0:f7c60d3e7b8a 170 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
maclobdell 0:f7c60d3e7b8a 171 mbedtls_sha512_update( &ctx->accumulator, header, 2 );
maclobdell 0:f7c60d3e7b8a 172 mbedtls_sha512_update( &ctx->accumulator, p, use_len );
maclobdell 0:f7c60d3e7b8a 173 #else
maclobdell 0:f7c60d3e7b8a 174 mbedtls_sha256_update( &ctx->accumulator, header, 2 );
maclobdell 0:f7c60d3e7b8a 175 mbedtls_sha256_update( &ctx->accumulator, p, use_len );
maclobdell 0:f7c60d3e7b8a 176 #endif
maclobdell 0:f7c60d3e7b8a 177
maclobdell 0:f7c60d3e7b8a 178 return( 0 );
maclobdell 0:f7c60d3e7b8a 179 }
maclobdell 0:f7c60d3e7b8a 180
maclobdell 0:f7c60d3e7b8a 181 int mbedtls_entropy_update_manual( mbedtls_entropy_context *ctx,
maclobdell 0:f7c60d3e7b8a 182 const unsigned char *data, size_t len )
maclobdell 0:f7c60d3e7b8a 183 {
maclobdell 0:f7c60d3e7b8a 184 int ret;
maclobdell 0:f7c60d3e7b8a 185
maclobdell 0:f7c60d3e7b8a 186 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 187 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 188 return( ret );
maclobdell 0:f7c60d3e7b8a 189 #endif
maclobdell 0:f7c60d3e7b8a 190
maclobdell 0:f7c60d3e7b8a 191 ret = entropy_update( ctx, MBEDTLS_ENTROPY_SOURCE_MANUAL, data, len );
maclobdell 0:f7c60d3e7b8a 192
maclobdell 0:f7c60d3e7b8a 193 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 194 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
maclobdell 0:f7c60d3e7b8a 195 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
maclobdell 0:f7c60d3e7b8a 196 #endif
maclobdell 0:f7c60d3e7b8a 197
maclobdell 0:f7c60d3e7b8a 198 return( ret );
maclobdell 0:f7c60d3e7b8a 199 }
maclobdell 0:f7c60d3e7b8a 200
maclobdell 0:f7c60d3e7b8a 201 /*
maclobdell 0:f7c60d3e7b8a 202 * Run through the different sources to add entropy to our accumulator
maclobdell 0:f7c60d3e7b8a 203 */
maclobdell 0:f7c60d3e7b8a 204 static int entropy_gather_internal( mbedtls_entropy_context *ctx )
maclobdell 0:f7c60d3e7b8a 205 {
maclobdell 0:f7c60d3e7b8a 206 int ret, i, have_one_strong = 0;
maclobdell 0:f7c60d3e7b8a 207 unsigned char buf[MBEDTLS_ENTROPY_MAX_GATHER];
maclobdell 0:f7c60d3e7b8a 208 size_t olen;
maclobdell 0:f7c60d3e7b8a 209
maclobdell 0:f7c60d3e7b8a 210 if( ctx->source_count == 0 )
maclobdell 0:f7c60d3e7b8a 211 return( MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED );
maclobdell 0:f7c60d3e7b8a 212
maclobdell 0:f7c60d3e7b8a 213 /*
maclobdell 0:f7c60d3e7b8a 214 * Run through our entropy sources
maclobdell 0:f7c60d3e7b8a 215 */
maclobdell 0:f7c60d3e7b8a 216 for( i = 0; i < ctx->source_count; i++ )
maclobdell 0:f7c60d3e7b8a 217 {
maclobdell 0:f7c60d3e7b8a 218 if( ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG )
maclobdell 0:f7c60d3e7b8a 219 have_one_strong = 1;
maclobdell 0:f7c60d3e7b8a 220
maclobdell 0:f7c60d3e7b8a 221 olen = 0;
maclobdell 0:f7c60d3e7b8a 222 if( ( ret = ctx->source[i].f_source( ctx->source[i].p_source,
maclobdell 0:f7c60d3e7b8a 223 buf, MBEDTLS_ENTROPY_MAX_GATHER, &olen ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 224 {
maclobdell 0:f7c60d3e7b8a 225 return( ret );
maclobdell 0:f7c60d3e7b8a 226 }
maclobdell 0:f7c60d3e7b8a 227
maclobdell 0:f7c60d3e7b8a 228 /*
maclobdell 0:f7c60d3e7b8a 229 * Add if we actually gathered something
maclobdell 0:f7c60d3e7b8a 230 */
maclobdell 0:f7c60d3e7b8a 231 if( olen > 0 )
maclobdell 0:f7c60d3e7b8a 232 {
maclobdell 0:f7c60d3e7b8a 233 entropy_update( ctx, (unsigned char) i, buf, olen );
maclobdell 0:f7c60d3e7b8a 234 ctx->source[i].size += olen;
maclobdell 0:f7c60d3e7b8a 235 }
maclobdell 0:f7c60d3e7b8a 236 }
maclobdell 0:f7c60d3e7b8a 237
maclobdell 0:f7c60d3e7b8a 238 if( have_one_strong == 0 )
maclobdell 0:f7c60d3e7b8a 239 return( MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE );
maclobdell 0:f7c60d3e7b8a 240
maclobdell 0:f7c60d3e7b8a 241 return( 0 );
maclobdell 0:f7c60d3e7b8a 242 }
maclobdell 0:f7c60d3e7b8a 243
maclobdell 0:f7c60d3e7b8a 244 /*
maclobdell 0:f7c60d3e7b8a 245 * Thread-safe wrapper for entropy_gather_internal()
maclobdell 0:f7c60d3e7b8a 246 */
maclobdell 0:f7c60d3e7b8a 247 int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
maclobdell 0:f7c60d3e7b8a 248 {
maclobdell 0:f7c60d3e7b8a 249 int ret;
maclobdell 0:f7c60d3e7b8a 250
maclobdell 0:f7c60d3e7b8a 251 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 252 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 253 return( ret );
maclobdell 0:f7c60d3e7b8a 254 #endif
maclobdell 0:f7c60d3e7b8a 255
maclobdell 0:f7c60d3e7b8a 256 ret = entropy_gather_internal( ctx );
maclobdell 0:f7c60d3e7b8a 257
maclobdell 0:f7c60d3e7b8a 258 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 259 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
maclobdell 0:f7c60d3e7b8a 260 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
maclobdell 0:f7c60d3e7b8a 261 #endif
maclobdell 0:f7c60d3e7b8a 262
maclobdell 0:f7c60d3e7b8a 263 return( ret );
maclobdell 0:f7c60d3e7b8a 264 }
maclobdell 0:f7c60d3e7b8a 265
maclobdell 0:f7c60d3e7b8a 266 int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
maclobdell 0:f7c60d3e7b8a 267 {
maclobdell 0:f7c60d3e7b8a 268 int ret, count = 0, i, done;
maclobdell 0:f7c60d3e7b8a 269 mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
maclobdell 0:f7c60d3e7b8a 270 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
maclobdell 0:f7c60d3e7b8a 271
maclobdell 0:f7c60d3e7b8a 272 if( len > MBEDTLS_ENTROPY_BLOCK_SIZE )
maclobdell 0:f7c60d3e7b8a 273 return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
maclobdell 0:f7c60d3e7b8a 274
maclobdell 0:f7c60d3e7b8a 275 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 276 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 277 return( ret );
maclobdell 0:f7c60d3e7b8a 278 #endif
maclobdell 0:f7c60d3e7b8a 279
maclobdell 0:f7c60d3e7b8a 280 /*
maclobdell 0:f7c60d3e7b8a 281 * Always gather extra entropy before a call
maclobdell 0:f7c60d3e7b8a 282 */
maclobdell 0:f7c60d3e7b8a 283 do
maclobdell 0:f7c60d3e7b8a 284 {
maclobdell 0:f7c60d3e7b8a 285 if( count++ > ENTROPY_MAX_LOOP )
maclobdell 0:f7c60d3e7b8a 286 {
maclobdell 0:f7c60d3e7b8a 287 ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
maclobdell 0:f7c60d3e7b8a 288 goto exit;
maclobdell 0:f7c60d3e7b8a 289 }
maclobdell 0:f7c60d3e7b8a 290
maclobdell 0:f7c60d3e7b8a 291 if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 292 goto exit;
maclobdell 0:f7c60d3e7b8a 293
maclobdell 0:f7c60d3e7b8a 294 done = 1;
maclobdell 0:f7c60d3e7b8a 295 for( i = 0; i < ctx->source_count; i++ )
maclobdell 0:f7c60d3e7b8a 296 if( ctx->source[i].size < ctx->source[i].threshold )
maclobdell 0:f7c60d3e7b8a 297 done = 0;
maclobdell 0:f7c60d3e7b8a 298 }
maclobdell 0:f7c60d3e7b8a 299 while( ! done );
maclobdell 0:f7c60d3e7b8a 300
maclobdell 0:f7c60d3e7b8a 301 memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
maclobdell 0:f7c60d3e7b8a 302
maclobdell 0:f7c60d3e7b8a 303 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
maclobdell 0:f7c60d3e7b8a 304 mbedtls_sha512_finish( &ctx->accumulator, buf );
maclobdell 0:f7c60d3e7b8a 305
maclobdell 0:f7c60d3e7b8a 306 /*
maclobdell 0:f7c60d3e7b8a 307 * Reset accumulator and counters and recycle existing entropy
maclobdell 0:f7c60d3e7b8a 308 */
maclobdell 0:f7c60d3e7b8a 309 memset( &ctx->accumulator, 0, sizeof( mbedtls_sha512_context ) );
maclobdell 0:f7c60d3e7b8a 310 mbedtls_sha512_starts( &ctx->accumulator, 0 );
maclobdell 0:f7c60d3e7b8a 311 mbedtls_sha512_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
maclobdell 0:f7c60d3e7b8a 312
maclobdell 0:f7c60d3e7b8a 313 /*
maclobdell 0:f7c60d3e7b8a 314 * Perform second SHA-512 on entropy
maclobdell 0:f7c60d3e7b8a 315 */
maclobdell 0:f7c60d3e7b8a 316 mbedtls_sha512( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
maclobdell 0:f7c60d3e7b8a 317 #else /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
maclobdell 0:f7c60d3e7b8a 318 mbedtls_sha256_finish( &ctx->accumulator, buf );
maclobdell 0:f7c60d3e7b8a 319
maclobdell 0:f7c60d3e7b8a 320 /*
maclobdell 0:f7c60d3e7b8a 321 * Reset accumulator and counters and recycle existing entropy
maclobdell 0:f7c60d3e7b8a 322 */
maclobdell 0:f7c60d3e7b8a 323 memset( &ctx->accumulator, 0, sizeof( mbedtls_sha256_context ) );
maclobdell 0:f7c60d3e7b8a 324 mbedtls_sha256_starts( &ctx->accumulator, 0 );
maclobdell 0:f7c60d3e7b8a 325 mbedtls_sha256_update( &ctx->accumulator, buf, MBEDTLS_ENTROPY_BLOCK_SIZE );
maclobdell 0:f7c60d3e7b8a 326
maclobdell 0:f7c60d3e7b8a 327 /*
maclobdell 0:f7c60d3e7b8a 328 * Perform second SHA-256 on entropy
maclobdell 0:f7c60d3e7b8a 329 */
maclobdell 0:f7c60d3e7b8a 330 mbedtls_sha256( buf, MBEDTLS_ENTROPY_BLOCK_SIZE, buf, 0 );
maclobdell 0:f7c60d3e7b8a 331 #endif /* MBEDTLS_ENTROPY_SHA512_ACCUMULATOR */
maclobdell 0:f7c60d3e7b8a 332
maclobdell 0:f7c60d3e7b8a 333 for( i = 0; i < ctx->source_count; i++ )
maclobdell 0:f7c60d3e7b8a 334 ctx->source[i].size = 0;
maclobdell 0:f7c60d3e7b8a 335
maclobdell 0:f7c60d3e7b8a 336 memcpy( output, buf, len );
maclobdell 0:f7c60d3e7b8a 337
maclobdell 0:f7c60d3e7b8a 338 ret = 0;
maclobdell 0:f7c60d3e7b8a 339
maclobdell 0:f7c60d3e7b8a 340 exit:
maclobdell 0:f7c60d3e7b8a 341 #if defined(MBEDTLS_THREADING_C)
maclobdell 0:f7c60d3e7b8a 342 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
maclobdell 0:f7c60d3e7b8a 343 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
maclobdell 0:f7c60d3e7b8a 344 #endif
maclobdell 0:f7c60d3e7b8a 345
maclobdell 0:f7c60d3e7b8a 346 return( ret );
maclobdell 0:f7c60d3e7b8a 347 }
maclobdell 0:f7c60d3e7b8a 348
maclobdell 0:f7c60d3e7b8a 349 #if defined(MBEDTLS_FS_IO)
maclobdell 0:f7c60d3e7b8a 350 int mbedtls_entropy_write_seed_file( mbedtls_entropy_context *ctx, const char *path )
maclobdell 0:f7c60d3e7b8a 351 {
maclobdell 0:f7c60d3e7b8a 352 int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
maclobdell 0:f7c60d3e7b8a 353 FILE *f;
maclobdell 0:f7c60d3e7b8a 354 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
maclobdell 0:f7c60d3e7b8a 355
maclobdell 0:f7c60d3e7b8a 356 if( ( f = fopen( path, "wb" ) ) == NULL )
maclobdell 0:f7c60d3e7b8a 357 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
maclobdell 0:f7c60d3e7b8a 358
maclobdell 0:f7c60d3e7b8a 359 if( ( ret = mbedtls_entropy_func( ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 360 goto exit;
maclobdell 0:f7c60d3e7b8a 361
maclobdell 0:f7c60d3e7b8a 362 if( fwrite( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) != MBEDTLS_ENTROPY_BLOCK_SIZE )
maclobdell 0:f7c60d3e7b8a 363 {
maclobdell 0:f7c60d3e7b8a 364 ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
maclobdell 0:f7c60d3e7b8a 365 goto exit;
maclobdell 0:f7c60d3e7b8a 366 }
maclobdell 0:f7c60d3e7b8a 367
maclobdell 0:f7c60d3e7b8a 368 ret = 0;
maclobdell 0:f7c60d3e7b8a 369
maclobdell 0:f7c60d3e7b8a 370 exit:
maclobdell 0:f7c60d3e7b8a 371 fclose( f );
maclobdell 0:f7c60d3e7b8a 372 return( ret );
maclobdell 0:f7c60d3e7b8a 373 }
maclobdell 0:f7c60d3e7b8a 374
maclobdell 0:f7c60d3e7b8a 375 int mbedtls_entropy_update_seed_file( mbedtls_entropy_context *ctx, const char *path )
maclobdell 0:f7c60d3e7b8a 376 {
maclobdell 0:f7c60d3e7b8a 377 FILE *f;
maclobdell 0:f7c60d3e7b8a 378 size_t n;
maclobdell 0:f7c60d3e7b8a 379 unsigned char buf[ MBEDTLS_ENTROPY_MAX_SEED_SIZE ];
maclobdell 0:f7c60d3e7b8a 380
maclobdell 0:f7c60d3e7b8a 381 if( ( f = fopen( path, "rb" ) ) == NULL )
maclobdell 0:f7c60d3e7b8a 382 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
maclobdell 0:f7c60d3e7b8a 383
maclobdell 0:f7c60d3e7b8a 384 fseek( f, 0, SEEK_END );
maclobdell 0:f7c60d3e7b8a 385 n = (size_t) ftell( f );
maclobdell 0:f7c60d3e7b8a 386 fseek( f, 0, SEEK_SET );
maclobdell 0:f7c60d3e7b8a 387
maclobdell 0:f7c60d3e7b8a 388 if( n > MBEDTLS_ENTROPY_MAX_SEED_SIZE )
maclobdell 0:f7c60d3e7b8a 389 n = MBEDTLS_ENTROPY_MAX_SEED_SIZE;
maclobdell 0:f7c60d3e7b8a 390
maclobdell 0:f7c60d3e7b8a 391 if( fread( buf, 1, n, f ) != n )
maclobdell 0:f7c60d3e7b8a 392 {
maclobdell 0:f7c60d3e7b8a 393 fclose( f );
maclobdell 0:f7c60d3e7b8a 394 return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
maclobdell 0:f7c60d3e7b8a 395 }
maclobdell 0:f7c60d3e7b8a 396
maclobdell 0:f7c60d3e7b8a 397 fclose( f );
maclobdell 0:f7c60d3e7b8a 398
maclobdell 0:f7c60d3e7b8a 399 mbedtls_entropy_update_manual( ctx, buf, n );
maclobdell 0:f7c60d3e7b8a 400
maclobdell 0:f7c60d3e7b8a 401 return( mbedtls_entropy_write_seed_file( ctx, path ) );
maclobdell 0:f7c60d3e7b8a 402 }
maclobdell 0:f7c60d3e7b8a 403 #endif /* MBEDTLS_FS_IO */
maclobdell 0:f7c60d3e7b8a 404
maclobdell 0:f7c60d3e7b8a 405 #if defined(MBEDTLS_SELF_TEST)
maclobdell 0:f7c60d3e7b8a 406 /*
maclobdell 0:f7c60d3e7b8a 407 * Dummy source function
maclobdell 0:f7c60d3e7b8a 408 */
maclobdell 0:f7c60d3e7b8a 409 static int entropy_dummy_source( void *data, unsigned char *output,
maclobdell 0:f7c60d3e7b8a 410 size_t len, size_t *olen )
maclobdell 0:f7c60d3e7b8a 411 {
maclobdell 0:f7c60d3e7b8a 412 ((void) data);
maclobdell 0:f7c60d3e7b8a 413
maclobdell 0:f7c60d3e7b8a 414 memset( output, 0x2a, len );
maclobdell 0:f7c60d3e7b8a 415 *olen = len;
maclobdell 0:f7c60d3e7b8a 416
maclobdell 0:f7c60d3e7b8a 417 return( 0 );
maclobdell 0:f7c60d3e7b8a 418 }
maclobdell 0:f7c60d3e7b8a 419
maclobdell 0:f7c60d3e7b8a 420 /*
maclobdell 0:f7c60d3e7b8a 421 * The actual entropy quality is hard to test, but we can at least
maclobdell 0:f7c60d3e7b8a 422 * test that the functions don't cause errors and write the correct
maclobdell 0:f7c60d3e7b8a 423 * amount of data to buffers.
maclobdell 0:f7c60d3e7b8a 424 */
maclobdell 0:f7c60d3e7b8a 425 int mbedtls_entropy_self_test( int verbose )
maclobdell 0:f7c60d3e7b8a 426 {
maclobdell 0:f7c60d3e7b8a 427 int ret = 0;
maclobdell 0:f7c60d3e7b8a 428 mbedtls_entropy_context ctx;
maclobdell 0:f7c60d3e7b8a 429 unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
maclobdell 0:f7c60d3e7b8a 430 unsigned char acc[MBEDTLS_ENTROPY_BLOCK_SIZE] = { 0 };
maclobdell 0:f7c60d3e7b8a 431 size_t i, j;
maclobdell 0:f7c60d3e7b8a 432
maclobdell 0:f7c60d3e7b8a 433 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 434 mbedtls_printf( " ENTROPY test: " );
maclobdell 0:f7c60d3e7b8a 435
maclobdell 0:f7c60d3e7b8a 436 mbedtls_entropy_init( &ctx );
maclobdell 0:f7c60d3e7b8a 437
maclobdell 0:f7c60d3e7b8a 438 /* First do a gather to make sure we have default sources */
maclobdell 0:f7c60d3e7b8a 439 if( ( ret = mbedtls_entropy_gather( &ctx ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 440 goto cleanup;
maclobdell 0:f7c60d3e7b8a 441
maclobdell 0:f7c60d3e7b8a 442 ret = mbedtls_entropy_add_source( &ctx, entropy_dummy_source, NULL, 16,
maclobdell 0:f7c60d3e7b8a 443 MBEDTLS_ENTROPY_SOURCE_WEAK );
maclobdell 0:f7c60d3e7b8a 444 if( ret != 0 )
maclobdell 0:f7c60d3e7b8a 445 goto cleanup;
maclobdell 0:f7c60d3e7b8a 446
maclobdell 0:f7c60d3e7b8a 447 if( ( ret = mbedtls_entropy_update_manual( &ctx, buf, sizeof buf ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 448 goto cleanup;
maclobdell 0:f7c60d3e7b8a 449
maclobdell 0:f7c60d3e7b8a 450 /*
maclobdell 0:f7c60d3e7b8a 451 * To test that mbedtls_entropy_func writes correct number of bytes:
maclobdell 0:f7c60d3e7b8a 452 * - use the whole buffer and rely on ASan to detect overruns
maclobdell 0:f7c60d3e7b8a 453 * - collect entropy 8 times and OR the result in an accumulator:
maclobdell 0:f7c60d3e7b8a 454 * any byte should then be 0 with probably 2^(-64), so requiring
maclobdell 0:f7c60d3e7b8a 455 * each of the 32 or 64 bytes to be non-zero has a false failure rate
maclobdell 0:f7c60d3e7b8a 456 * of at most 2^(-58) which is acceptable.
maclobdell 0:f7c60d3e7b8a 457 */
maclobdell 0:f7c60d3e7b8a 458 for( i = 0; i < 8; i++ )
maclobdell 0:f7c60d3e7b8a 459 {
maclobdell 0:f7c60d3e7b8a 460 if( ( ret = mbedtls_entropy_func( &ctx, buf, sizeof( buf ) ) ) != 0 )
maclobdell 0:f7c60d3e7b8a 461 goto cleanup;
maclobdell 0:f7c60d3e7b8a 462
maclobdell 0:f7c60d3e7b8a 463 for( j = 0; j < sizeof( buf ); j++ )
maclobdell 0:f7c60d3e7b8a 464 acc[j] |= buf[j];
maclobdell 0:f7c60d3e7b8a 465 }
maclobdell 0:f7c60d3e7b8a 466
maclobdell 0:f7c60d3e7b8a 467 for( j = 0; j < sizeof( buf ); j++ )
maclobdell 0:f7c60d3e7b8a 468 {
maclobdell 0:f7c60d3e7b8a 469 if( acc[j] == 0 )
maclobdell 0:f7c60d3e7b8a 470 {
maclobdell 0:f7c60d3e7b8a 471 ret = 1;
maclobdell 0:f7c60d3e7b8a 472 goto cleanup;
maclobdell 0:f7c60d3e7b8a 473 }
maclobdell 0:f7c60d3e7b8a 474 }
maclobdell 0:f7c60d3e7b8a 475
maclobdell 0:f7c60d3e7b8a 476 cleanup:
maclobdell 0:f7c60d3e7b8a 477 mbedtls_entropy_free( &ctx );
maclobdell 0:f7c60d3e7b8a 478
maclobdell 0:f7c60d3e7b8a 479 if( verbose != 0 )
maclobdell 0:f7c60d3e7b8a 480 {
maclobdell 0:f7c60d3e7b8a 481 if( ret != 0 )
maclobdell 0:f7c60d3e7b8a 482 mbedtls_printf( "failed\n" );
maclobdell 0:f7c60d3e7b8a 483 else
maclobdell 0:f7c60d3e7b8a 484 mbedtls_printf( "passed\n" );
maclobdell 0:f7c60d3e7b8a 485
maclobdell 0:f7c60d3e7b8a 486 mbedtls_printf( "\n" );
maclobdell 0:f7c60d3e7b8a 487 }
maclobdell 0:f7c60d3e7b8a 488
maclobdell 0:f7c60d3e7b8a 489 return( ret != 0 );
maclobdell 0:f7c60d3e7b8a 490 }
maclobdell 0:f7c60d3e7b8a 491 #endif /* MBEDTLS_SELF_TEST */
maclobdell 0:f7c60d3e7b8a 492
maclobdell 0:f7c60d3e7b8a 493 #endif /* MBEDTLS_ENTROPY_C */