Kev Mann / mbed-dev-OS5_10_4

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features/mbedtls/src/pem.c@0:38ceb79fef03, 2018-11-28 (annotated)

Committer:
kevman
Date:
Wed Nov 28 15:10:15 2018 +0000
Revision:
0:38ceb79fef03
RTC modified

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kevman 0:38ceb79fef03 1 /*
kevman 0:38ceb79fef03 2 * Privacy Enhanced Mail (PEM) decoding
kevman 0:38ceb79fef03 3 *
kevman 0:38ceb79fef03 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
kevman 0:38ceb79fef03 5 * SPDX-License-Identifier: Apache-2.0
kevman 0:38ceb79fef03 6 *
kevman 0:38ceb79fef03 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
kevman 0:38ceb79fef03 8 * not use this file except in compliance with the License.
kevman 0:38ceb79fef03 9 * You may obtain a copy of the License at
kevman 0:38ceb79fef03 10 *
kevman 0:38ceb79fef03 11 * http://www.apache.org/licenses/LICENSE-2.0
kevman 0:38ceb79fef03 12 *
kevman 0:38ceb79fef03 13 * Unless required by applicable law or agreed to in writing, software
kevman 0:38ceb79fef03 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
kevman 0:38ceb79fef03 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
kevman 0:38ceb79fef03 16 * See the License for the specific language governing permissions and
kevman 0:38ceb79fef03 17 * limitations under the License.
kevman 0:38ceb79fef03 18 *
kevman 0:38ceb79fef03 19 * This file is part of mbed TLS (https://tls.mbed.org)
kevman 0:38ceb79fef03 20 */
kevman 0:38ceb79fef03 21
kevman 0:38ceb79fef03 22 #if !defined(MBEDTLS_CONFIG_FILE)
kevman 0:38ceb79fef03 23 #include "mbedtls/config.h"
kevman 0:38ceb79fef03 24 #else
kevman 0:38ceb79fef03 25 #include MBEDTLS_CONFIG_FILE
kevman 0:38ceb79fef03 26 #endif
kevman 0:38ceb79fef03 27
kevman 0:38ceb79fef03 28 #if defined(MBEDTLS_PEM_PARSE_C) || defined(MBEDTLS_PEM_WRITE_C)
kevman 0:38ceb79fef03 29
kevman 0:38ceb79fef03 30 #include "mbedtls/pem.h"
kevman 0:38ceb79fef03 31 #include "mbedtls/base64.h"
kevman 0:38ceb79fef03 32 #include "mbedtls/des.h"
kevman 0:38ceb79fef03 33 #include "mbedtls/aes.h"
kevman 0:38ceb79fef03 34 #include "mbedtls/md5.h"
kevman 0:38ceb79fef03 35 #include "mbedtls/cipher.h"
kevman 0:38ceb79fef03 36 #include "mbedtls/platform_util.h"
kevman 0:38ceb79fef03 37
kevman 0:38ceb79fef03 38 #include <string.h>
kevman 0:38ceb79fef03 39
kevman 0:38ceb79fef03 40 #if defined(MBEDTLS_PLATFORM_C)
kevman 0:38ceb79fef03 41 #include "mbedtls/platform.h"
kevman 0:38ceb79fef03 42 #else
kevman 0:38ceb79fef03 43 #include <stdlib.h>
kevman 0:38ceb79fef03 44 #define mbedtls_calloc calloc
kevman 0:38ceb79fef03 45 #define mbedtls_free free
kevman 0:38ceb79fef03 46 #endif
kevman 0:38ceb79fef03 47
kevman 0:38ceb79fef03 48 #if defined(MBEDTLS_PEM_PARSE_C)
kevman 0:38ceb79fef03 49 void mbedtls_pem_init( mbedtls_pem_context *ctx )
kevman 0:38ceb79fef03 50 {
kevman 0:38ceb79fef03 51 memset( ctx, 0, sizeof( mbedtls_pem_context ) );
kevman 0:38ceb79fef03 52 }
kevman 0:38ceb79fef03 53
kevman 0:38ceb79fef03 54 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
kevman 0:38ceb79fef03 55 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
kevman 0:38ceb79fef03 56 /*
kevman 0:38ceb79fef03 57 * Read a 16-byte hex string and convert it to binary
kevman 0:38ceb79fef03 58 */
kevman 0:38ceb79fef03 59 static int pem_get_iv( const unsigned char *s, unsigned char *iv,
kevman 0:38ceb79fef03 60 size_t iv_len )
kevman 0:38ceb79fef03 61 {
kevman 0:38ceb79fef03 62 size_t i, j, k;
kevman 0:38ceb79fef03 63
kevman 0:38ceb79fef03 64 memset( iv, 0, iv_len );
kevman 0:38ceb79fef03 65
kevman 0:38ceb79fef03 66 for( i = 0; i < iv_len * 2; i++, s++ )
kevman 0:38ceb79fef03 67 {
kevman 0:38ceb79fef03 68 if( *s >= '0' && *s <= '9' ) j = *s - '0'; else
kevman 0:38ceb79fef03 69 if( *s >= 'A' && *s <= 'F' ) j = *s - '7'; else
kevman 0:38ceb79fef03 70 if( *s >= 'a' && *s <= 'f' ) j = *s - 'W'; else
kevman 0:38ceb79fef03 71 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
kevman 0:38ceb79fef03 72
kevman 0:38ceb79fef03 73 k = ( ( i & 1 ) != 0 ) ? j : j << 4;
kevman 0:38ceb79fef03 74
kevman 0:38ceb79fef03 75 iv[i >> 1] = (unsigned char)( iv[i >> 1] | k );
kevman 0:38ceb79fef03 76 }
kevman 0:38ceb79fef03 77
kevman 0:38ceb79fef03 78 return( 0 );
kevman 0:38ceb79fef03 79 }
kevman 0:38ceb79fef03 80
kevman 0:38ceb79fef03 81 static int pem_pbkdf1( unsigned char *key, size_t keylen,
kevman 0:38ceb79fef03 82 unsigned char *iv,
kevman 0:38ceb79fef03 83 const unsigned char *pwd, size_t pwdlen )
kevman 0:38ceb79fef03 84 {
kevman 0:38ceb79fef03 85 mbedtls_md5_context md5_ctx;
kevman 0:38ceb79fef03 86 unsigned char md5sum[16];
kevman 0:38ceb79fef03 87 size_t use_len;
kevman 0:38ceb79fef03 88 int ret;
kevman 0:38ceb79fef03 89
kevman 0:38ceb79fef03 90 mbedtls_md5_init( &md5_ctx );
kevman 0:38ceb79fef03 91
kevman 0:38ceb79fef03 92 /*
kevman 0:38ceb79fef03 93 * key[ 0..15] = MD5(pwd || IV)
kevman 0:38ceb79fef03 94 */
kevman 0:38ceb79fef03 95 if( ( ret = mbedtls_md5_starts_ret( &md5_ctx ) ) != 0 )
kevman 0:38ceb79fef03 96 goto exit;
kevman 0:38ceb79fef03 97 if( ( ret = mbedtls_md5_update_ret( &md5_ctx, pwd, pwdlen ) ) != 0 )
kevman 0:38ceb79fef03 98 goto exit;
kevman 0:38ceb79fef03 99 if( ( ret = mbedtls_md5_update_ret( &md5_ctx, iv, 8 ) ) != 0 )
kevman 0:38ceb79fef03 100 goto exit;
kevman 0:38ceb79fef03 101 if( ( ret = mbedtls_md5_finish_ret( &md5_ctx, md5sum ) ) != 0 )
kevman 0:38ceb79fef03 102 goto exit;
kevman 0:38ceb79fef03 103
kevman 0:38ceb79fef03 104 if( keylen <= 16 )
kevman 0:38ceb79fef03 105 {
kevman 0:38ceb79fef03 106 memcpy( key, md5sum, keylen );
kevman 0:38ceb79fef03 107 goto exit;
kevman 0:38ceb79fef03 108 }
kevman 0:38ceb79fef03 109
kevman 0:38ceb79fef03 110 memcpy( key, md5sum, 16 );
kevman 0:38ceb79fef03 111
kevman 0:38ceb79fef03 112 /*
kevman 0:38ceb79fef03 113 * key[16..23] = MD5(key[ 0..15] || pwd || IV])
kevman 0:38ceb79fef03 114 */
kevman 0:38ceb79fef03 115 if( ( ret = mbedtls_md5_starts_ret( &md5_ctx ) ) != 0 )
kevman 0:38ceb79fef03 116 goto exit;
kevman 0:38ceb79fef03 117 if( ( ret = mbedtls_md5_update_ret( &md5_ctx, md5sum, 16 ) ) != 0 )
kevman 0:38ceb79fef03 118 goto exit;
kevman 0:38ceb79fef03 119 if( ( ret = mbedtls_md5_update_ret( &md5_ctx, pwd, pwdlen ) ) != 0 )
kevman 0:38ceb79fef03 120 goto exit;
kevman 0:38ceb79fef03 121 if( ( ret = mbedtls_md5_update_ret( &md5_ctx, iv, 8 ) ) != 0 )
kevman 0:38ceb79fef03 122 goto exit;
kevman 0:38ceb79fef03 123 if( ( ret = mbedtls_md5_finish_ret( &md5_ctx, md5sum ) ) != 0 )
kevman 0:38ceb79fef03 124 goto exit;
kevman 0:38ceb79fef03 125
kevman 0:38ceb79fef03 126 use_len = 16;
kevman 0:38ceb79fef03 127 if( keylen < 32 )
kevman 0:38ceb79fef03 128 use_len = keylen - 16;
kevman 0:38ceb79fef03 129
kevman 0:38ceb79fef03 130 memcpy( key + 16, md5sum, use_len );
kevman 0:38ceb79fef03 131
kevman 0:38ceb79fef03 132 exit:
kevman 0:38ceb79fef03 133 mbedtls_md5_free( &md5_ctx );
kevman 0:38ceb79fef03 134 mbedtls_platform_zeroize( md5sum, 16 );
kevman 0:38ceb79fef03 135
kevman 0:38ceb79fef03 136 return( ret );
kevman 0:38ceb79fef03 137 }
kevman 0:38ceb79fef03 138
kevman 0:38ceb79fef03 139 #if defined(MBEDTLS_DES_C)
kevman 0:38ceb79fef03 140 /*
kevman 0:38ceb79fef03 141 * Decrypt with DES-CBC, using PBKDF1 for key derivation
kevman 0:38ceb79fef03 142 */
kevman 0:38ceb79fef03 143 static int pem_des_decrypt( unsigned char des_iv[8],
kevman 0:38ceb79fef03 144 unsigned char *buf, size_t buflen,
kevman 0:38ceb79fef03 145 const unsigned char *pwd, size_t pwdlen )
kevman 0:38ceb79fef03 146 {
kevman 0:38ceb79fef03 147 mbedtls_des_context des_ctx;
kevman 0:38ceb79fef03 148 unsigned char des_key[8];
kevman 0:38ceb79fef03 149 int ret;
kevman 0:38ceb79fef03 150
kevman 0:38ceb79fef03 151 mbedtls_des_init( &des_ctx );
kevman 0:38ceb79fef03 152
kevman 0:38ceb79fef03 153 if( ( ret = pem_pbkdf1( des_key, 8, des_iv, pwd, pwdlen ) ) != 0 )
kevman 0:38ceb79fef03 154 goto exit;
kevman 0:38ceb79fef03 155
kevman 0:38ceb79fef03 156 if( ( ret = mbedtls_des_setkey_dec( &des_ctx, des_key ) ) != 0 )
kevman 0:38ceb79fef03 157 goto exit;
kevman 0:38ceb79fef03 158 ret = mbedtls_des_crypt_cbc( &des_ctx, MBEDTLS_DES_DECRYPT, buflen,
kevman 0:38ceb79fef03 159 des_iv, buf, buf );
kevman 0:38ceb79fef03 160
kevman 0:38ceb79fef03 161 exit:
kevman 0:38ceb79fef03 162 mbedtls_des_free( &des_ctx );
kevman 0:38ceb79fef03 163 mbedtls_platform_zeroize( des_key, 8 );
kevman 0:38ceb79fef03 164
kevman 0:38ceb79fef03 165 return( ret );
kevman 0:38ceb79fef03 166 }
kevman 0:38ceb79fef03 167
kevman 0:38ceb79fef03 168 /*
kevman 0:38ceb79fef03 169 * Decrypt with 3DES-CBC, using PBKDF1 for key derivation
kevman 0:38ceb79fef03 170 */
kevman 0:38ceb79fef03 171 static int pem_des3_decrypt( unsigned char des3_iv[8],
kevman 0:38ceb79fef03 172 unsigned char *buf, size_t buflen,
kevman 0:38ceb79fef03 173 const unsigned char *pwd, size_t pwdlen )
kevman 0:38ceb79fef03 174 {
kevman 0:38ceb79fef03 175 mbedtls_des3_context des3_ctx;
kevman 0:38ceb79fef03 176 unsigned char des3_key[24];
kevman 0:38ceb79fef03 177 int ret;
kevman 0:38ceb79fef03 178
kevman 0:38ceb79fef03 179 mbedtls_des3_init( &des3_ctx );
kevman 0:38ceb79fef03 180
kevman 0:38ceb79fef03 181 if( ( ret = pem_pbkdf1( des3_key, 24, des3_iv, pwd, pwdlen ) ) != 0 )
kevman 0:38ceb79fef03 182 goto exit;
kevman 0:38ceb79fef03 183
kevman 0:38ceb79fef03 184 if( ( ret = mbedtls_des3_set3key_dec( &des3_ctx, des3_key ) ) != 0 )
kevman 0:38ceb79fef03 185 goto exit;
kevman 0:38ceb79fef03 186 ret = mbedtls_des3_crypt_cbc( &des3_ctx, MBEDTLS_DES_DECRYPT, buflen,
kevman 0:38ceb79fef03 187 des3_iv, buf, buf );
kevman 0:38ceb79fef03 188
kevman 0:38ceb79fef03 189 exit:
kevman 0:38ceb79fef03 190 mbedtls_des3_free( &des3_ctx );
kevman 0:38ceb79fef03 191 mbedtls_platform_zeroize( des3_key, 24 );
kevman 0:38ceb79fef03 192
kevman 0:38ceb79fef03 193 return( ret );
kevman 0:38ceb79fef03 194 }
kevman 0:38ceb79fef03 195 #endif /* MBEDTLS_DES_C */
kevman 0:38ceb79fef03 196
kevman 0:38ceb79fef03 197 #if defined(MBEDTLS_AES_C)
kevman 0:38ceb79fef03 198 /*
kevman 0:38ceb79fef03 199 * Decrypt with AES-XXX-CBC, using PBKDF1 for key derivation
kevman 0:38ceb79fef03 200 */
kevman 0:38ceb79fef03 201 static int pem_aes_decrypt( unsigned char aes_iv[16], unsigned int keylen,
kevman 0:38ceb79fef03 202 unsigned char *buf, size_t buflen,
kevman 0:38ceb79fef03 203 const unsigned char *pwd, size_t pwdlen )
kevman 0:38ceb79fef03 204 {
kevman 0:38ceb79fef03 205 mbedtls_aes_context aes_ctx;
kevman 0:38ceb79fef03 206 unsigned char aes_key[32];
kevman 0:38ceb79fef03 207 int ret;
kevman 0:38ceb79fef03 208
kevman 0:38ceb79fef03 209 mbedtls_aes_init( &aes_ctx );
kevman 0:38ceb79fef03 210
kevman 0:38ceb79fef03 211 if( ( ret = pem_pbkdf1( aes_key, keylen, aes_iv, pwd, pwdlen ) ) != 0 )
kevman 0:38ceb79fef03 212 goto exit;
kevman 0:38ceb79fef03 213
kevman 0:38ceb79fef03 214 if( ( ret = mbedtls_aes_setkey_dec( &aes_ctx, aes_key, keylen * 8 ) ) != 0 )
kevman 0:38ceb79fef03 215 goto exit;
kevman 0:38ceb79fef03 216 ret = mbedtls_aes_crypt_cbc( &aes_ctx, MBEDTLS_AES_DECRYPT, buflen,
kevman 0:38ceb79fef03 217 aes_iv, buf, buf );
kevman 0:38ceb79fef03 218
kevman 0:38ceb79fef03 219 exit:
kevman 0:38ceb79fef03 220 mbedtls_aes_free( &aes_ctx );
kevman 0:38ceb79fef03 221 mbedtls_platform_zeroize( aes_key, keylen );
kevman 0:38ceb79fef03 222
kevman 0:38ceb79fef03 223 return( ret );
kevman 0:38ceb79fef03 224 }
kevman 0:38ceb79fef03 225 #endif /* MBEDTLS_AES_C */
kevman 0:38ceb79fef03 226
kevman 0:38ceb79fef03 227 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
kevman 0:38ceb79fef03 228 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
kevman 0:38ceb79fef03 229
kevman 0:38ceb79fef03 230 int mbedtls_pem_read_buffer( mbedtls_pem_context *ctx, const char *header, const char *footer,
kevman 0:38ceb79fef03 231 const unsigned char *data, const unsigned char *pwd,
kevman 0:38ceb79fef03 232 size_t pwdlen, size_t *use_len )
kevman 0:38ceb79fef03 233 {
kevman 0:38ceb79fef03 234 int ret, enc;
kevman 0:38ceb79fef03 235 size_t len;
kevman 0:38ceb79fef03 236 unsigned char *buf;
kevman 0:38ceb79fef03 237 const unsigned char *s1, *s2, *end;
kevman 0:38ceb79fef03 238 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
kevman 0:38ceb79fef03 239 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
kevman 0:38ceb79fef03 240 unsigned char pem_iv[16];
kevman 0:38ceb79fef03 241 mbedtls_cipher_type_t enc_alg = MBEDTLS_CIPHER_NONE;
kevman 0:38ceb79fef03 242 #else
kevman 0:38ceb79fef03 243 ((void) pwd);
kevman 0:38ceb79fef03 244 ((void) pwdlen);
kevman 0:38ceb79fef03 245 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
kevman 0:38ceb79fef03 246 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
kevman 0:38ceb79fef03 247
kevman 0:38ceb79fef03 248 if( ctx == NULL )
kevman 0:38ceb79fef03 249 return( MBEDTLS_ERR_PEM_BAD_INPUT_DATA );
kevman 0:38ceb79fef03 250
kevman 0:38ceb79fef03 251 s1 = (unsigned char *) strstr( (const char *) data, header );
kevman 0:38ceb79fef03 252
kevman 0:38ceb79fef03 253 if( s1 == NULL )
kevman 0:38ceb79fef03 254 return( MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT );
kevman 0:38ceb79fef03 255
kevman 0:38ceb79fef03 256 s2 = (unsigned char *) strstr( (const char *) data, footer );
kevman 0:38ceb79fef03 257
kevman 0:38ceb79fef03 258 if( s2 == NULL || s2 <= s1 )
kevman 0:38ceb79fef03 259 return( MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT );
kevman 0:38ceb79fef03 260
kevman 0:38ceb79fef03 261 s1 += strlen( header );
kevman 0:38ceb79fef03 262 if( *s1 == ' ' ) s1++;
kevman 0:38ceb79fef03 263 if( *s1 == '\r' ) s1++;
kevman 0:38ceb79fef03 264 if( *s1 == '\n' ) s1++;
kevman 0:38ceb79fef03 265 else return( MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT );
kevman 0:38ceb79fef03 266
kevman 0:38ceb79fef03 267 end = s2;
kevman 0:38ceb79fef03 268 end += strlen( footer );
kevman 0:38ceb79fef03 269 if( *end == ' ' ) end++;
kevman 0:38ceb79fef03 270 if( *end == '\r' ) end++;
kevman 0:38ceb79fef03 271 if( *end == '\n' ) end++;
kevman 0:38ceb79fef03 272 *use_len = end - data;
kevman 0:38ceb79fef03 273
kevman 0:38ceb79fef03 274 enc = 0;
kevman 0:38ceb79fef03 275
kevman 0:38ceb79fef03 276 if( s2 - s1 >= 22 && memcmp( s1, "Proc-Type: 4,ENCRYPTED", 22 ) == 0 )
kevman 0:38ceb79fef03 277 {
kevman 0:38ceb79fef03 278 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
kevman 0:38ceb79fef03 279 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
kevman 0:38ceb79fef03 280 enc++;
kevman 0:38ceb79fef03 281
kevman 0:38ceb79fef03 282 s1 += 22;
kevman 0:38ceb79fef03 283 if( *s1 == '\r' ) s1++;
kevman 0:38ceb79fef03 284 if( *s1 == '\n' ) s1++;
kevman 0:38ceb79fef03 285 else return( MBEDTLS_ERR_PEM_INVALID_DATA );
kevman 0:38ceb79fef03 286
kevman 0:38ceb79fef03 287
kevman 0:38ceb79fef03 288 #if defined(MBEDTLS_DES_C)
kevman 0:38ceb79fef03 289 if( s2 - s1 >= 23 && memcmp( s1, "DEK-Info: DES-EDE3-CBC,", 23 ) == 0 )
kevman 0:38ceb79fef03 290 {
kevman 0:38ceb79fef03 291 enc_alg = MBEDTLS_CIPHER_DES_EDE3_CBC;
kevman 0:38ceb79fef03 292
kevman 0:38ceb79fef03 293 s1 += 23;
kevman 0:38ceb79fef03 294 if( s2 - s1 < 16 || pem_get_iv( s1, pem_iv, 8 ) != 0 )
kevman 0:38ceb79fef03 295 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
kevman 0:38ceb79fef03 296
kevman 0:38ceb79fef03 297 s1 += 16;
kevman 0:38ceb79fef03 298 }
kevman 0:38ceb79fef03 299 else if( s2 - s1 >= 18 && memcmp( s1, "DEK-Info: DES-CBC,", 18 ) == 0 )
kevman 0:38ceb79fef03 300 {
kevman 0:38ceb79fef03 301 enc_alg = MBEDTLS_CIPHER_DES_CBC;
kevman 0:38ceb79fef03 302
kevman 0:38ceb79fef03 303 s1 += 18;
kevman 0:38ceb79fef03 304 if( s2 - s1 < 16 || pem_get_iv( s1, pem_iv, 8) != 0 )
kevman 0:38ceb79fef03 305 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
kevman 0:38ceb79fef03 306
kevman 0:38ceb79fef03 307 s1 += 16;
kevman 0:38ceb79fef03 308 }
kevman 0:38ceb79fef03 309 #endif /* MBEDTLS_DES_C */
kevman 0:38ceb79fef03 310
kevman 0:38ceb79fef03 311 #if defined(MBEDTLS_AES_C)
kevman 0:38ceb79fef03 312 if( s2 - s1 >= 14 && memcmp( s1, "DEK-Info: AES-", 14 ) == 0 )
kevman 0:38ceb79fef03 313 {
kevman 0:38ceb79fef03 314 if( s2 - s1 < 22 )
kevman 0:38ceb79fef03 315 return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
kevman 0:38ceb79fef03 316 else if( memcmp( s1, "DEK-Info: AES-128-CBC,", 22 ) == 0 )
kevman 0:38ceb79fef03 317 enc_alg = MBEDTLS_CIPHER_AES_128_CBC;
kevman 0:38ceb79fef03 318 else if( memcmp( s1, "DEK-Info: AES-192-CBC,", 22 ) == 0 )
kevman 0:38ceb79fef03 319 enc_alg = MBEDTLS_CIPHER_AES_192_CBC;
kevman 0:38ceb79fef03 320 else if( memcmp( s1, "DEK-Info: AES-256-CBC,", 22 ) == 0 )
kevman 0:38ceb79fef03 321 enc_alg = MBEDTLS_CIPHER_AES_256_CBC;
kevman 0:38ceb79fef03 322 else
kevman 0:38ceb79fef03 323 return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
kevman 0:38ceb79fef03 324
kevman 0:38ceb79fef03 325 s1 += 22;
kevman 0:38ceb79fef03 326 if( s2 - s1 < 32 || pem_get_iv( s1, pem_iv, 16 ) != 0 )
kevman 0:38ceb79fef03 327 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
kevman 0:38ceb79fef03 328
kevman 0:38ceb79fef03 329 s1 += 32;
kevman 0:38ceb79fef03 330 }
kevman 0:38ceb79fef03 331 #endif /* MBEDTLS_AES_C */
kevman 0:38ceb79fef03 332
kevman 0:38ceb79fef03 333 if( enc_alg == MBEDTLS_CIPHER_NONE )
kevman 0:38ceb79fef03 334 return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
kevman 0:38ceb79fef03 335
kevman 0:38ceb79fef03 336 if( *s1 == '\r' ) s1++;
kevman 0:38ceb79fef03 337 if( *s1 == '\n' ) s1++;
kevman 0:38ceb79fef03 338 else return( MBEDTLS_ERR_PEM_INVALID_DATA );
kevman 0:38ceb79fef03 339 #else
kevman 0:38ceb79fef03 340 return( MBEDTLS_ERR_PEM_FEATURE_UNAVAILABLE );
kevman 0:38ceb79fef03 341 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
kevman 0:38ceb79fef03 342 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
kevman 0:38ceb79fef03 343 }
kevman 0:38ceb79fef03 344
kevman 0:38ceb79fef03 345 if( s1 >= s2 )
kevman 0:38ceb79fef03 346 return( MBEDTLS_ERR_PEM_INVALID_DATA );
kevman 0:38ceb79fef03 347
kevman 0:38ceb79fef03 348 ret = mbedtls_base64_decode( NULL, 0, &len, s1, s2 - s1 );
kevman 0:38ceb79fef03 349
kevman 0:38ceb79fef03 350 if( ret == MBEDTLS_ERR_BASE64_INVALID_CHARACTER )
kevman 0:38ceb79fef03 351 return( MBEDTLS_ERR_PEM_INVALID_DATA + ret );
kevman 0:38ceb79fef03 352
kevman 0:38ceb79fef03 353 if( ( buf = mbedtls_calloc( 1, len ) ) == NULL )
kevman 0:38ceb79fef03 354 return( MBEDTLS_ERR_PEM_ALLOC_FAILED );
kevman 0:38ceb79fef03 355
kevman 0:38ceb79fef03 356 if( ( ret = mbedtls_base64_decode( buf, len, &len, s1, s2 - s1 ) ) != 0 )
kevman 0:38ceb79fef03 357 {
kevman 0:38ceb79fef03 358 mbedtls_platform_zeroize( buf, len );
kevman 0:38ceb79fef03 359 mbedtls_free( buf );
kevman 0:38ceb79fef03 360 return( MBEDTLS_ERR_PEM_INVALID_DATA + ret );
kevman 0:38ceb79fef03 361 }
kevman 0:38ceb79fef03 362
kevman 0:38ceb79fef03 363 if( enc != 0 )
kevman 0:38ceb79fef03 364 {
kevman 0:38ceb79fef03 365 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
kevman 0:38ceb79fef03 366 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
kevman 0:38ceb79fef03 367 if( pwd == NULL )
kevman 0:38ceb79fef03 368 {
kevman 0:38ceb79fef03 369 mbedtls_platform_zeroize( buf, len );
kevman 0:38ceb79fef03 370 mbedtls_free( buf );
kevman 0:38ceb79fef03 371 return( MBEDTLS_ERR_PEM_PASSWORD_REQUIRED );
kevman 0:38ceb79fef03 372 }
kevman 0:38ceb79fef03 373
kevman 0:38ceb79fef03 374 ret = 0;
kevman 0:38ceb79fef03 375
kevman 0:38ceb79fef03 376 #if defined(MBEDTLS_DES_C)
kevman 0:38ceb79fef03 377 if( enc_alg == MBEDTLS_CIPHER_DES_EDE3_CBC )
kevman 0:38ceb79fef03 378 ret = pem_des3_decrypt( pem_iv, buf, len, pwd, pwdlen );
kevman 0:38ceb79fef03 379 else if( enc_alg == MBEDTLS_CIPHER_DES_CBC )
kevman 0:38ceb79fef03 380 ret = pem_des_decrypt( pem_iv, buf, len, pwd, pwdlen );
kevman 0:38ceb79fef03 381 #endif /* MBEDTLS_DES_C */
kevman 0:38ceb79fef03 382
kevman 0:38ceb79fef03 383 #if defined(MBEDTLS_AES_C)
kevman 0:38ceb79fef03 384 if( enc_alg == MBEDTLS_CIPHER_AES_128_CBC )
kevman 0:38ceb79fef03 385 ret = pem_aes_decrypt( pem_iv, 16, buf, len, pwd, pwdlen );
kevman 0:38ceb79fef03 386 else if( enc_alg == MBEDTLS_CIPHER_AES_192_CBC )
kevman 0:38ceb79fef03 387 ret = pem_aes_decrypt( pem_iv, 24, buf, len, pwd, pwdlen );
kevman 0:38ceb79fef03 388 else if( enc_alg == MBEDTLS_CIPHER_AES_256_CBC )
kevman 0:38ceb79fef03 389 ret = pem_aes_decrypt( pem_iv, 32, buf, len, pwd, pwdlen );
kevman 0:38ceb79fef03 390 #endif /* MBEDTLS_AES_C */
kevman 0:38ceb79fef03 391
kevman 0:38ceb79fef03 392 if( ret != 0 )
kevman 0:38ceb79fef03 393 {
kevman 0:38ceb79fef03 394 mbedtls_free( buf );
kevman 0:38ceb79fef03 395 return( ret );
kevman 0:38ceb79fef03 396 }
kevman 0:38ceb79fef03 397
kevman 0:38ceb79fef03 398 /*
kevman 0:38ceb79fef03 399 * The result will be ASN.1 starting with a SEQUENCE tag, with 1 to 3
kevman 0:38ceb79fef03 400 * length bytes (allow 4 to be sure) in all known use cases.
kevman 0:38ceb79fef03 401 *
kevman 0:38ceb79fef03 402 * Use that as a heuristic to try to detect password mismatches.
kevman 0:38ceb79fef03 403 */
kevman 0:38ceb79fef03 404 if( len <= 2 || buf[0] != 0x30 || buf[1] > 0x83 )
kevman 0:38ceb79fef03 405 {
kevman 0:38ceb79fef03 406 mbedtls_platform_zeroize( buf, len );
kevman 0:38ceb79fef03 407 mbedtls_free( buf );
kevman 0:38ceb79fef03 408 return( MBEDTLS_ERR_PEM_PASSWORD_MISMATCH );
kevman 0:38ceb79fef03 409 }
kevman 0:38ceb79fef03 410 #else
kevman 0:38ceb79fef03 411 mbedtls_platform_zeroize( buf, len );
kevman 0:38ceb79fef03 412 mbedtls_free( buf );
kevman 0:38ceb79fef03 413 return( MBEDTLS_ERR_PEM_FEATURE_UNAVAILABLE );
kevman 0:38ceb79fef03 414 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
kevman 0:38ceb79fef03 415 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
kevman 0:38ceb79fef03 416 }
kevman 0:38ceb79fef03 417
kevman 0:38ceb79fef03 418 ctx->buf = buf;
kevman 0:38ceb79fef03 419 ctx->buflen = len;
kevman 0:38ceb79fef03 420
kevman 0:38ceb79fef03 421 return( 0 );
kevman 0:38ceb79fef03 422 }
kevman 0:38ceb79fef03 423
kevman 0:38ceb79fef03 424 void mbedtls_pem_free( mbedtls_pem_context *ctx )
kevman 0:38ceb79fef03 425 {
kevman 0:38ceb79fef03 426 if( ctx->buf != NULL )
kevman 0:38ceb79fef03 427 mbedtls_platform_zeroize( ctx->buf, ctx->buflen );
kevman 0:38ceb79fef03 428 mbedtls_free( ctx->buf );
kevman 0:38ceb79fef03 429 mbedtls_free( ctx->info );
kevman 0:38ceb79fef03 430
kevman 0:38ceb79fef03 431 mbedtls_platform_zeroize( ctx, sizeof( mbedtls_pem_context ) );
kevman 0:38ceb79fef03 432 }
kevman 0:38ceb79fef03 433 #endif /* MBEDTLS_PEM_PARSE_C */
kevman 0:38ceb79fef03 434
kevman 0:38ceb79fef03 435 #if defined(MBEDTLS_PEM_WRITE_C)
kevman 0:38ceb79fef03 436 int mbedtls_pem_write_buffer( const char *header, const char *footer,
kevman 0:38ceb79fef03 437 const unsigned char *der_data, size_t der_len,
kevman 0:38ceb79fef03 438 unsigned char *buf, size_t buf_len, size_t *olen )
kevman 0:38ceb79fef03 439 {
kevman 0:38ceb79fef03 440 int ret;
kevman 0:38ceb79fef03 441 unsigned char *encode_buf = NULL, *c, *p = buf;
kevman 0:38ceb79fef03 442 size_t len = 0, use_len, add_len = 0;
kevman 0:38ceb79fef03 443
kevman 0:38ceb79fef03 444 mbedtls_base64_encode( NULL, 0, &use_len, der_data, der_len );
kevman 0:38ceb79fef03 445 add_len = strlen( header ) + strlen( footer ) + ( use_len / 64 ) + 1;
kevman 0:38ceb79fef03 446
kevman 0:38ceb79fef03 447 if( use_len + add_len > buf_len )
kevman 0:38ceb79fef03 448 {
kevman 0:38ceb79fef03 449 *olen = use_len + add_len;
kevman 0:38ceb79fef03 450 return( MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL );
kevman 0:38ceb79fef03 451 }
kevman 0:38ceb79fef03 452
kevman 0:38ceb79fef03 453 if( use_len != 0 &&
kevman 0:38ceb79fef03 454 ( ( encode_buf = mbedtls_calloc( 1, use_len ) ) == NULL ) )
kevman 0:38ceb79fef03 455 return( MBEDTLS_ERR_PEM_ALLOC_FAILED );
kevman 0:38ceb79fef03 456
kevman 0:38ceb79fef03 457 if( ( ret = mbedtls_base64_encode( encode_buf, use_len, &use_len, der_data,
kevman 0:38ceb79fef03 458 der_len ) ) != 0 )
kevman 0:38ceb79fef03 459 {
kevman 0:38ceb79fef03 460 mbedtls_free( encode_buf );
kevman 0:38ceb79fef03 461 return( ret );
kevman 0:38ceb79fef03 462 }
kevman 0:38ceb79fef03 463
kevman 0:38ceb79fef03 464 memcpy( p, header, strlen( header ) );
kevman 0:38ceb79fef03 465 p += strlen( header );
kevman 0:38ceb79fef03 466 c = encode_buf;
kevman 0:38ceb79fef03 467
kevman 0:38ceb79fef03 468 while( use_len )
kevman 0:38ceb79fef03 469 {
kevman 0:38ceb79fef03 470 len = ( use_len > 64 ) ? 64 : use_len;
kevman 0:38ceb79fef03 471 memcpy( p, c, len );
kevman 0:38ceb79fef03 472 use_len -= len;
kevman 0:38ceb79fef03 473 p += len;
kevman 0:38ceb79fef03 474 c += len;
kevman 0:38ceb79fef03 475 *p++ = '\n';
kevman 0:38ceb79fef03 476 }
kevman 0:38ceb79fef03 477
kevman 0:38ceb79fef03 478 memcpy( p, footer, strlen( footer ) );
kevman 0:38ceb79fef03 479 p += strlen( footer );
kevman 0:38ceb79fef03 480
kevman 0:38ceb79fef03 481 *p++ = '\0';
kevman 0:38ceb79fef03 482 *olen = p - buf;
kevman 0:38ceb79fef03 483
kevman 0:38ceb79fef03 484 mbedtls_free( encode_buf );
kevman 0:38ceb79fef03 485 return( 0 );
kevman 0:38ceb79fef03 486 }
kevman 0:38ceb79fef03 487 #endif /* MBEDTLS_PEM_WRITE_C */
kevman 0:38ceb79fef03 488 #endif /* MBEDTLS_PEM_PARSE_C || MBEDTLS_PEM_WRITE_C */