sandbox / mbedtls

mbedtls ported to mbed-classic

Fork of mbedtls by Christopher Haster

source/pem.c@1:24750b9ad5ef, 2016-01-22 (annotated)

Committer:
Christopher Haster
Date:
Fri Jan 22 16:44:49 2016 -0600
Revision:
1:24750b9ad5ef
Initial move of mbedtls to mercurial

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Christopher Haster 1:24750b9ad5ef 1 /*
Christopher Haster 1:24750b9ad5ef 2 * Privacy Enhanced Mail (PEM) decoding
Christopher Haster 1:24750b9ad5ef 3 *
Christopher Haster 1:24750b9ad5ef 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
Christopher Haster 1:24750b9ad5ef 5 * SPDX-License-Identifier: Apache-2.0
Christopher Haster 1:24750b9ad5ef 6 *
Christopher Haster 1:24750b9ad5ef 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
Christopher Haster 1:24750b9ad5ef 8 * not use this file except in compliance with the License.
Christopher Haster 1:24750b9ad5ef 9 * You may obtain a copy of the License at
Christopher Haster 1:24750b9ad5ef 10 *
Christopher Haster 1:24750b9ad5ef 11 * http://www.apache.org/licenses/LICENSE-2.0
Christopher Haster 1:24750b9ad5ef 12 *
Christopher Haster 1:24750b9ad5ef 13 * Unless required by applicable law or agreed to in writing, software
Christopher Haster 1:24750b9ad5ef 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
Christopher Haster 1:24750b9ad5ef 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
Christopher Haster 1:24750b9ad5ef 16 * See the License for the specific language governing permissions and
Christopher Haster 1:24750b9ad5ef 17 * limitations under the License.
Christopher Haster 1:24750b9ad5ef 18 *
Christopher Haster 1:24750b9ad5ef 19 * This file is part of mbed TLS (https://tls.mbed.org)
Christopher Haster 1:24750b9ad5ef 20 */
Christopher Haster 1:24750b9ad5ef 21
Christopher Haster 1:24750b9ad5ef 22 #if !defined(MBEDTLS_CONFIG_FILE)
Christopher Haster 1:24750b9ad5ef 23 #include "mbedtls/config.h"
Christopher Haster 1:24750b9ad5ef 24 #else
Christopher Haster 1:24750b9ad5ef 25 #include MBEDTLS_CONFIG_FILE
Christopher Haster 1:24750b9ad5ef 26 #endif
Christopher Haster 1:24750b9ad5ef 27
Christopher Haster 1:24750b9ad5ef 28 #if defined(MBEDTLS_PEM_PARSE_C) || defined(MBEDTLS_PEM_WRITE_C)
Christopher Haster 1:24750b9ad5ef 29
Christopher Haster 1:24750b9ad5ef 30 #include "mbedtls/pem.h"
Christopher Haster 1:24750b9ad5ef 31 #include "mbedtls/base64.h"
Christopher Haster 1:24750b9ad5ef 32 #include "mbedtls/des.h"
Christopher Haster 1:24750b9ad5ef 33 #include "mbedtls/aes.h"
Christopher Haster 1:24750b9ad5ef 34 #include "mbedtls/md5.h"
Christopher Haster 1:24750b9ad5ef 35 #include "mbedtls/cipher.h"
Christopher Haster 1:24750b9ad5ef 36
Christopher Haster 1:24750b9ad5ef 37 #include <string.h>
Christopher Haster 1:24750b9ad5ef 38
Christopher Haster 1:24750b9ad5ef 39 #if defined(MBEDTLS_PLATFORM_C)
Christopher Haster 1:24750b9ad5ef 40 #include "mbedtls/platform.h"
Christopher Haster 1:24750b9ad5ef 41 #else
Christopher Haster 1:24750b9ad5ef 42 #include <stdlib.h>
Christopher Haster 1:24750b9ad5ef 43 #define mbedtls_calloc calloc
Christopher Haster 1:24750b9ad5ef 44 #define mbedtls_free free
Christopher Haster 1:24750b9ad5ef 45 #endif
Christopher Haster 1:24750b9ad5ef 46
Christopher Haster 1:24750b9ad5ef 47 /* Implementation that should never be optimized out by the compiler */
Christopher Haster 1:24750b9ad5ef 48 static void mbedtls_zeroize( void *v, size_t n ) {
Christopher Haster 1:24750b9ad5ef 49 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
Christopher Haster 1:24750b9ad5ef 50 }
Christopher Haster 1:24750b9ad5ef 51
Christopher Haster 1:24750b9ad5ef 52 #if defined(MBEDTLS_PEM_PARSE_C)
Christopher Haster 1:24750b9ad5ef 53 void mbedtls_pem_init( mbedtls_pem_context *ctx )
Christopher Haster 1:24750b9ad5ef 54 {
Christopher Haster 1:24750b9ad5ef 55 memset( ctx, 0, sizeof( mbedtls_pem_context ) );
Christopher Haster 1:24750b9ad5ef 56 }
Christopher Haster 1:24750b9ad5ef 57
Christopher Haster 1:24750b9ad5ef 58 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
Christopher Haster 1:24750b9ad5ef 59 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
Christopher Haster 1:24750b9ad5ef 60 /*
Christopher Haster 1:24750b9ad5ef 61 * Read a 16-byte hex string and convert it to binary
Christopher Haster 1:24750b9ad5ef 62 */
Christopher Haster 1:24750b9ad5ef 63 static int pem_get_iv( const unsigned char *s, unsigned char *iv,
Christopher Haster 1:24750b9ad5ef 64 size_t iv_len )
Christopher Haster 1:24750b9ad5ef 65 {
Christopher Haster 1:24750b9ad5ef 66 size_t i, j, k;
Christopher Haster 1:24750b9ad5ef 67
Christopher Haster 1:24750b9ad5ef 68 memset( iv, 0, iv_len );
Christopher Haster 1:24750b9ad5ef 69
Christopher Haster 1:24750b9ad5ef 70 for( i = 0; i < iv_len * 2; i++, s++ )
Christopher Haster 1:24750b9ad5ef 71 {
Christopher Haster 1:24750b9ad5ef 72 if( *s >= '0' && *s <= '9' ) j = *s - '0'; else
Christopher Haster 1:24750b9ad5ef 73 if( *s >= 'A' && *s <= 'F' ) j = *s - '7'; else
Christopher Haster 1:24750b9ad5ef 74 if( *s >= 'a' && *s <= 'f' ) j = *s - 'W'; else
Christopher Haster 1:24750b9ad5ef 75 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
Christopher Haster 1:24750b9ad5ef 76
Christopher Haster 1:24750b9ad5ef 77 k = ( ( i & 1 ) != 0 ) ? j : j << 4;
Christopher Haster 1:24750b9ad5ef 78
Christopher Haster 1:24750b9ad5ef 79 iv[i >> 1] = (unsigned char)( iv[i >> 1] | k );
Christopher Haster 1:24750b9ad5ef 80 }
Christopher Haster 1:24750b9ad5ef 81
Christopher Haster 1:24750b9ad5ef 82 return( 0 );
Christopher Haster 1:24750b9ad5ef 83 }
Christopher Haster 1:24750b9ad5ef 84
Christopher Haster 1:24750b9ad5ef 85 static void pem_pbkdf1( unsigned char *key, size_t keylen,
Christopher Haster 1:24750b9ad5ef 86 unsigned char *iv,
Christopher Haster 1:24750b9ad5ef 87 const unsigned char *pwd, size_t pwdlen )
Christopher Haster 1:24750b9ad5ef 88 {
Christopher Haster 1:24750b9ad5ef 89 mbedtls_md5_context md5_ctx;
Christopher Haster 1:24750b9ad5ef 90 unsigned char md5sum[16];
Christopher Haster 1:24750b9ad5ef 91 size_t use_len;
Christopher Haster 1:24750b9ad5ef 92
Christopher Haster 1:24750b9ad5ef 93 mbedtls_md5_init( &md5_ctx );
Christopher Haster 1:24750b9ad5ef 94
Christopher Haster 1:24750b9ad5ef 95 /*
Christopher Haster 1:24750b9ad5ef 96 * key[ 0..15] = MD5(pwd || IV)
Christopher Haster 1:24750b9ad5ef 97 */
Christopher Haster 1:24750b9ad5ef 98 mbedtls_md5_starts( &md5_ctx );
Christopher Haster 1:24750b9ad5ef 99 mbedtls_md5_update( &md5_ctx, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 100 mbedtls_md5_update( &md5_ctx, iv, 8 );
Christopher Haster 1:24750b9ad5ef 101 mbedtls_md5_finish( &md5_ctx, md5sum );
Christopher Haster 1:24750b9ad5ef 102
Christopher Haster 1:24750b9ad5ef 103 if( keylen <= 16 )
Christopher Haster 1:24750b9ad5ef 104 {
Christopher Haster 1:24750b9ad5ef 105 memcpy( key, md5sum, keylen );
Christopher Haster 1:24750b9ad5ef 106
Christopher Haster 1:24750b9ad5ef 107 mbedtls_md5_free( &md5_ctx );
Christopher Haster 1:24750b9ad5ef 108 mbedtls_zeroize( md5sum, 16 );
Christopher Haster 1:24750b9ad5ef 109 return;
Christopher Haster 1:24750b9ad5ef 110 }
Christopher Haster 1:24750b9ad5ef 111
Christopher Haster 1:24750b9ad5ef 112 memcpy( key, md5sum, 16 );
Christopher Haster 1:24750b9ad5ef 113
Christopher Haster 1:24750b9ad5ef 114 /*
Christopher Haster 1:24750b9ad5ef 115 * key[16..23] = MD5(key[ 0..15] || pwd || IV])
Christopher Haster 1:24750b9ad5ef 116 */
Christopher Haster 1:24750b9ad5ef 117 mbedtls_md5_starts( &md5_ctx );
Christopher Haster 1:24750b9ad5ef 118 mbedtls_md5_update( &md5_ctx, md5sum, 16 );
Christopher Haster 1:24750b9ad5ef 119 mbedtls_md5_update( &md5_ctx, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 120 mbedtls_md5_update( &md5_ctx, iv, 8 );
Christopher Haster 1:24750b9ad5ef 121 mbedtls_md5_finish( &md5_ctx, md5sum );
Christopher Haster 1:24750b9ad5ef 122
Christopher Haster 1:24750b9ad5ef 123 use_len = 16;
Christopher Haster 1:24750b9ad5ef 124 if( keylen < 32 )
Christopher Haster 1:24750b9ad5ef 125 use_len = keylen - 16;
Christopher Haster 1:24750b9ad5ef 126
Christopher Haster 1:24750b9ad5ef 127 memcpy( key + 16, md5sum, use_len );
Christopher Haster 1:24750b9ad5ef 128
Christopher Haster 1:24750b9ad5ef 129 mbedtls_md5_free( &md5_ctx );
Christopher Haster 1:24750b9ad5ef 130 mbedtls_zeroize( md5sum, 16 );
Christopher Haster 1:24750b9ad5ef 131 }
Christopher Haster 1:24750b9ad5ef 132
Christopher Haster 1:24750b9ad5ef 133 #if defined(MBEDTLS_DES_C)
Christopher Haster 1:24750b9ad5ef 134 /*
Christopher Haster 1:24750b9ad5ef 135 * Decrypt with DES-CBC, using PBKDF1 for key derivation
Christopher Haster 1:24750b9ad5ef 136 */
Christopher Haster 1:24750b9ad5ef 137 static void pem_des_decrypt( unsigned char des_iv[8],
Christopher Haster 1:24750b9ad5ef 138 unsigned char *buf, size_t buflen,
Christopher Haster 1:24750b9ad5ef 139 const unsigned char *pwd, size_t pwdlen )
Christopher Haster 1:24750b9ad5ef 140 {
Christopher Haster 1:24750b9ad5ef 141 mbedtls_des_context des_ctx;
Christopher Haster 1:24750b9ad5ef 142 unsigned char des_key[8];
Christopher Haster 1:24750b9ad5ef 143
Christopher Haster 1:24750b9ad5ef 144 mbedtls_des_init( &des_ctx );
Christopher Haster 1:24750b9ad5ef 145
Christopher Haster 1:24750b9ad5ef 146 pem_pbkdf1( des_key, 8, des_iv, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 147
Christopher Haster 1:24750b9ad5ef 148 mbedtls_des_setkey_dec( &des_ctx, des_key );
Christopher Haster 1:24750b9ad5ef 149 mbedtls_des_crypt_cbc( &des_ctx, MBEDTLS_DES_DECRYPT, buflen,
Christopher Haster 1:24750b9ad5ef 150 des_iv, buf, buf );
Christopher Haster 1:24750b9ad5ef 151
Christopher Haster 1:24750b9ad5ef 152 mbedtls_des_free( &des_ctx );
Christopher Haster 1:24750b9ad5ef 153 mbedtls_zeroize( des_key, 8 );
Christopher Haster 1:24750b9ad5ef 154 }
Christopher Haster 1:24750b9ad5ef 155
Christopher Haster 1:24750b9ad5ef 156 /*
Christopher Haster 1:24750b9ad5ef 157 * Decrypt with 3DES-CBC, using PBKDF1 for key derivation
Christopher Haster 1:24750b9ad5ef 158 */
Christopher Haster 1:24750b9ad5ef 159 static void pem_des3_decrypt( unsigned char des3_iv[8],
Christopher Haster 1:24750b9ad5ef 160 unsigned char *buf, size_t buflen,
Christopher Haster 1:24750b9ad5ef 161 const unsigned char *pwd, size_t pwdlen )
Christopher Haster 1:24750b9ad5ef 162 {
Christopher Haster 1:24750b9ad5ef 163 mbedtls_des3_context des3_ctx;
Christopher Haster 1:24750b9ad5ef 164 unsigned char des3_key[24];
Christopher Haster 1:24750b9ad5ef 165
Christopher Haster 1:24750b9ad5ef 166 mbedtls_des3_init( &des3_ctx );
Christopher Haster 1:24750b9ad5ef 167
Christopher Haster 1:24750b9ad5ef 168 pem_pbkdf1( des3_key, 24, des3_iv, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 169
Christopher Haster 1:24750b9ad5ef 170 mbedtls_des3_set3key_dec( &des3_ctx, des3_key );
Christopher Haster 1:24750b9ad5ef 171 mbedtls_des3_crypt_cbc( &des3_ctx, MBEDTLS_DES_DECRYPT, buflen,
Christopher Haster 1:24750b9ad5ef 172 des3_iv, buf, buf );
Christopher Haster 1:24750b9ad5ef 173
Christopher Haster 1:24750b9ad5ef 174 mbedtls_des3_free( &des3_ctx );
Christopher Haster 1:24750b9ad5ef 175 mbedtls_zeroize( des3_key, 24 );
Christopher Haster 1:24750b9ad5ef 176 }
Christopher Haster 1:24750b9ad5ef 177 #endif /* MBEDTLS_DES_C */
Christopher Haster 1:24750b9ad5ef 178
Christopher Haster 1:24750b9ad5ef 179 #if defined(MBEDTLS_AES_C)
Christopher Haster 1:24750b9ad5ef 180 /*
Christopher Haster 1:24750b9ad5ef 181 * Decrypt with AES-XXX-CBC, using PBKDF1 for key derivation
Christopher Haster 1:24750b9ad5ef 182 */
Christopher Haster 1:24750b9ad5ef 183 static void pem_aes_decrypt( unsigned char aes_iv[16], unsigned int keylen,
Christopher Haster 1:24750b9ad5ef 184 unsigned char *buf, size_t buflen,
Christopher Haster 1:24750b9ad5ef 185 const unsigned char *pwd, size_t pwdlen )
Christopher Haster 1:24750b9ad5ef 186 {
Christopher Haster 1:24750b9ad5ef 187 mbedtls_aes_context aes_ctx;
Christopher Haster 1:24750b9ad5ef 188 unsigned char aes_key[32];
Christopher Haster 1:24750b9ad5ef 189
Christopher Haster 1:24750b9ad5ef 190 mbedtls_aes_init( &aes_ctx );
Christopher Haster 1:24750b9ad5ef 191
Christopher Haster 1:24750b9ad5ef 192 pem_pbkdf1( aes_key, keylen, aes_iv, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 193
Christopher Haster 1:24750b9ad5ef 194 mbedtls_aes_setkey_dec( &aes_ctx, aes_key, keylen * 8 );
Christopher Haster 1:24750b9ad5ef 195 mbedtls_aes_crypt_cbc( &aes_ctx, MBEDTLS_AES_DECRYPT, buflen,
Christopher Haster 1:24750b9ad5ef 196 aes_iv, buf, buf );
Christopher Haster 1:24750b9ad5ef 197
Christopher Haster 1:24750b9ad5ef 198 mbedtls_aes_free( &aes_ctx );
Christopher Haster 1:24750b9ad5ef 199 mbedtls_zeroize( aes_key, keylen );
Christopher Haster 1:24750b9ad5ef 200 }
Christopher Haster 1:24750b9ad5ef 201 #endif /* MBEDTLS_AES_C */
Christopher Haster 1:24750b9ad5ef 202
Christopher Haster 1:24750b9ad5ef 203 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
Christopher Haster 1:24750b9ad5ef 204 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
Christopher Haster 1:24750b9ad5ef 205
Christopher Haster 1:24750b9ad5ef 206 int mbedtls_pem_read_buffer( mbedtls_pem_context *ctx, const char *header, const char *footer,
Christopher Haster 1:24750b9ad5ef 207 const unsigned char *data, const unsigned char *pwd,
Christopher Haster 1:24750b9ad5ef 208 size_t pwdlen, size_t *use_len )
Christopher Haster 1:24750b9ad5ef 209 {
Christopher Haster 1:24750b9ad5ef 210 int ret, enc;
Christopher Haster 1:24750b9ad5ef 211 size_t len;
Christopher Haster 1:24750b9ad5ef 212 unsigned char *buf;
Christopher Haster 1:24750b9ad5ef 213 const unsigned char *s1, *s2, *end;
Christopher Haster 1:24750b9ad5ef 214 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
Christopher Haster 1:24750b9ad5ef 215 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
Christopher Haster 1:24750b9ad5ef 216 unsigned char pem_iv[16];
Christopher Haster 1:24750b9ad5ef 217 mbedtls_cipher_type_t enc_alg = MBEDTLS_CIPHER_NONE;
Christopher Haster 1:24750b9ad5ef 218 #else
Christopher Haster 1:24750b9ad5ef 219 ((void) pwd);
Christopher Haster 1:24750b9ad5ef 220 ((void) pwdlen);
Christopher Haster 1:24750b9ad5ef 221 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
Christopher Haster 1:24750b9ad5ef 222 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
Christopher Haster 1:24750b9ad5ef 223
Christopher Haster 1:24750b9ad5ef 224 if( ctx == NULL )
Christopher Haster 1:24750b9ad5ef 225 return( MBEDTLS_ERR_PEM_BAD_INPUT_DATA );
Christopher Haster 1:24750b9ad5ef 226
Christopher Haster 1:24750b9ad5ef 227 s1 = (unsigned char *) strstr( (const char *) data, header );
Christopher Haster 1:24750b9ad5ef 228
Christopher Haster 1:24750b9ad5ef 229 if( s1 == NULL )
Christopher Haster 1:24750b9ad5ef 230 return( MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT );
Christopher Haster 1:24750b9ad5ef 231
Christopher Haster 1:24750b9ad5ef 232 s2 = (unsigned char *) strstr( (const char *) data, footer );
Christopher Haster 1:24750b9ad5ef 233
Christopher Haster 1:24750b9ad5ef 234 if( s2 == NULL || s2 <= s1 )
Christopher Haster 1:24750b9ad5ef 235 return( MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT );
Christopher Haster 1:24750b9ad5ef 236
Christopher Haster 1:24750b9ad5ef 237 s1 += strlen( header );
Christopher Haster 1:24750b9ad5ef 238 if( *s1 == ' ' ) s1++;
Christopher Haster 1:24750b9ad5ef 239 if( *s1 == '\r' ) s1++;
Christopher Haster 1:24750b9ad5ef 240 if( *s1 == '\n' ) s1++;
Christopher Haster 1:24750b9ad5ef 241 else return( MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT );
Christopher Haster 1:24750b9ad5ef 242
Christopher Haster 1:24750b9ad5ef 243 end = s2;
Christopher Haster 1:24750b9ad5ef 244 end += strlen( footer );
Christopher Haster 1:24750b9ad5ef 245 if( *end == ' ' ) end++;
Christopher Haster 1:24750b9ad5ef 246 if( *end == '\r' ) end++;
Christopher Haster 1:24750b9ad5ef 247 if( *end == '\n' ) end++;
Christopher Haster 1:24750b9ad5ef 248 *use_len = end - data;
Christopher Haster 1:24750b9ad5ef 249
Christopher Haster 1:24750b9ad5ef 250 enc = 0;
Christopher Haster 1:24750b9ad5ef 251
Christopher Haster 1:24750b9ad5ef 252 if( memcmp( s1, "Proc-Type: 4,ENCRYPTED", 22 ) == 0 )
Christopher Haster 1:24750b9ad5ef 253 {
Christopher Haster 1:24750b9ad5ef 254 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
Christopher Haster 1:24750b9ad5ef 255 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
Christopher Haster 1:24750b9ad5ef 256 enc++;
Christopher Haster 1:24750b9ad5ef 257
Christopher Haster 1:24750b9ad5ef 258 s1 += 22;
Christopher Haster 1:24750b9ad5ef 259 if( *s1 == '\r' ) s1++;
Christopher Haster 1:24750b9ad5ef 260 if( *s1 == '\n' ) s1++;
Christopher Haster 1:24750b9ad5ef 261 else return( MBEDTLS_ERR_PEM_INVALID_DATA );
Christopher Haster 1:24750b9ad5ef 262
Christopher Haster 1:24750b9ad5ef 263
Christopher Haster 1:24750b9ad5ef 264 #if defined(MBEDTLS_DES_C)
Christopher Haster 1:24750b9ad5ef 265 if( memcmp( s1, "DEK-Info: DES-EDE3-CBC,", 23 ) == 0 )
Christopher Haster 1:24750b9ad5ef 266 {
Christopher Haster 1:24750b9ad5ef 267 enc_alg = MBEDTLS_CIPHER_DES_EDE3_CBC;
Christopher Haster 1:24750b9ad5ef 268
Christopher Haster 1:24750b9ad5ef 269 s1 += 23;
Christopher Haster 1:24750b9ad5ef 270 if( pem_get_iv( s1, pem_iv, 8 ) != 0 )
Christopher Haster 1:24750b9ad5ef 271 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
Christopher Haster 1:24750b9ad5ef 272
Christopher Haster 1:24750b9ad5ef 273 s1 += 16;
Christopher Haster 1:24750b9ad5ef 274 }
Christopher Haster 1:24750b9ad5ef 275 else if( memcmp( s1, "DEK-Info: DES-CBC,", 18 ) == 0 )
Christopher Haster 1:24750b9ad5ef 276 {
Christopher Haster 1:24750b9ad5ef 277 enc_alg = MBEDTLS_CIPHER_DES_CBC;
Christopher Haster 1:24750b9ad5ef 278
Christopher Haster 1:24750b9ad5ef 279 s1 += 18;
Christopher Haster 1:24750b9ad5ef 280 if( pem_get_iv( s1, pem_iv, 8) != 0 )
Christopher Haster 1:24750b9ad5ef 281 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
Christopher Haster 1:24750b9ad5ef 282
Christopher Haster 1:24750b9ad5ef 283 s1 += 16;
Christopher Haster 1:24750b9ad5ef 284 }
Christopher Haster 1:24750b9ad5ef 285 #endif /* MBEDTLS_DES_C */
Christopher Haster 1:24750b9ad5ef 286
Christopher Haster 1:24750b9ad5ef 287 #if defined(MBEDTLS_AES_C)
Christopher Haster 1:24750b9ad5ef 288 if( memcmp( s1, "DEK-Info: AES-", 14 ) == 0 )
Christopher Haster 1:24750b9ad5ef 289 {
Christopher Haster 1:24750b9ad5ef 290 if( memcmp( s1, "DEK-Info: AES-128-CBC,", 22 ) == 0 )
Christopher Haster 1:24750b9ad5ef 291 enc_alg = MBEDTLS_CIPHER_AES_128_CBC;
Christopher Haster 1:24750b9ad5ef 292 else if( memcmp( s1, "DEK-Info: AES-192-CBC,", 22 ) == 0 )
Christopher Haster 1:24750b9ad5ef 293 enc_alg = MBEDTLS_CIPHER_AES_192_CBC;
Christopher Haster 1:24750b9ad5ef 294 else if( memcmp( s1, "DEK-Info: AES-256-CBC,", 22 ) == 0 )
Christopher Haster 1:24750b9ad5ef 295 enc_alg = MBEDTLS_CIPHER_AES_256_CBC;
Christopher Haster 1:24750b9ad5ef 296 else
Christopher Haster 1:24750b9ad5ef 297 return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
Christopher Haster 1:24750b9ad5ef 298
Christopher Haster 1:24750b9ad5ef 299 s1 += 22;
Christopher Haster 1:24750b9ad5ef 300 if( pem_get_iv( s1, pem_iv, 16 ) != 0 )
Christopher Haster 1:24750b9ad5ef 301 return( MBEDTLS_ERR_PEM_INVALID_ENC_IV );
Christopher Haster 1:24750b9ad5ef 302
Christopher Haster 1:24750b9ad5ef 303 s1 += 32;
Christopher Haster 1:24750b9ad5ef 304 }
Christopher Haster 1:24750b9ad5ef 305 #endif /* MBEDTLS_AES_C */
Christopher Haster 1:24750b9ad5ef 306
Christopher Haster 1:24750b9ad5ef 307 if( enc_alg == MBEDTLS_CIPHER_NONE )
Christopher Haster 1:24750b9ad5ef 308 return( MBEDTLS_ERR_PEM_UNKNOWN_ENC_ALG );
Christopher Haster 1:24750b9ad5ef 309
Christopher Haster 1:24750b9ad5ef 310 if( *s1 == '\r' ) s1++;
Christopher Haster 1:24750b9ad5ef 311 if( *s1 == '\n' ) s1++;
Christopher Haster 1:24750b9ad5ef 312 else return( MBEDTLS_ERR_PEM_INVALID_DATA );
Christopher Haster 1:24750b9ad5ef 313 #else
Christopher Haster 1:24750b9ad5ef 314 return( MBEDTLS_ERR_PEM_FEATURE_UNAVAILABLE );
Christopher Haster 1:24750b9ad5ef 315 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
Christopher Haster 1:24750b9ad5ef 316 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
Christopher Haster 1:24750b9ad5ef 317 }
Christopher Haster 1:24750b9ad5ef 318
Christopher Haster 1:24750b9ad5ef 319 if( s1 == s2 )
Christopher Haster 1:24750b9ad5ef 320 return( MBEDTLS_ERR_PEM_INVALID_DATA );
Christopher Haster 1:24750b9ad5ef 321
Christopher Haster 1:24750b9ad5ef 322 ret = mbedtls_base64_decode( NULL, 0, &len, s1, s2 - s1 );
Christopher Haster 1:24750b9ad5ef 323
Christopher Haster 1:24750b9ad5ef 324 if( ret == MBEDTLS_ERR_BASE64_INVALID_CHARACTER )
Christopher Haster 1:24750b9ad5ef 325 return( MBEDTLS_ERR_PEM_INVALID_DATA + ret );
Christopher Haster 1:24750b9ad5ef 326
Christopher Haster 1:24750b9ad5ef 327 if( ( buf = mbedtls_calloc( 1, len ) ) == NULL )
Christopher Haster 1:24750b9ad5ef 328 return( MBEDTLS_ERR_PEM_ALLOC_FAILED );
Christopher Haster 1:24750b9ad5ef 329
Christopher Haster 1:24750b9ad5ef 330 if( ( ret = mbedtls_base64_decode( buf, len, &len, s1, s2 - s1 ) ) != 0 )
Christopher Haster 1:24750b9ad5ef 331 {
Christopher Haster 1:24750b9ad5ef 332 mbedtls_free( buf );
Christopher Haster 1:24750b9ad5ef 333 return( MBEDTLS_ERR_PEM_INVALID_DATA + ret );
Christopher Haster 1:24750b9ad5ef 334 }
Christopher Haster 1:24750b9ad5ef 335
Christopher Haster 1:24750b9ad5ef 336 if( enc != 0 )
Christopher Haster 1:24750b9ad5ef 337 {
Christopher Haster 1:24750b9ad5ef 338 #if defined(MBEDTLS_MD5_C) && defined(MBEDTLS_CIPHER_MODE_CBC) && \
Christopher Haster 1:24750b9ad5ef 339 ( defined(MBEDTLS_DES_C) || defined(MBEDTLS_AES_C) )
Christopher Haster 1:24750b9ad5ef 340 if( pwd == NULL )
Christopher Haster 1:24750b9ad5ef 341 {
Christopher Haster 1:24750b9ad5ef 342 mbedtls_free( buf );
Christopher Haster 1:24750b9ad5ef 343 return( MBEDTLS_ERR_PEM_PASSWORD_REQUIRED );
Christopher Haster 1:24750b9ad5ef 344 }
Christopher Haster 1:24750b9ad5ef 345
Christopher Haster 1:24750b9ad5ef 346 #if defined(MBEDTLS_DES_C)
Christopher Haster 1:24750b9ad5ef 347 if( enc_alg == MBEDTLS_CIPHER_DES_EDE3_CBC )
Christopher Haster 1:24750b9ad5ef 348 pem_des3_decrypt( pem_iv, buf, len, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 349 else if( enc_alg == MBEDTLS_CIPHER_DES_CBC )
Christopher Haster 1:24750b9ad5ef 350 pem_des_decrypt( pem_iv, buf, len, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 351 #endif /* MBEDTLS_DES_C */
Christopher Haster 1:24750b9ad5ef 352
Christopher Haster 1:24750b9ad5ef 353 #if defined(MBEDTLS_AES_C)
Christopher Haster 1:24750b9ad5ef 354 if( enc_alg == MBEDTLS_CIPHER_AES_128_CBC )
Christopher Haster 1:24750b9ad5ef 355 pem_aes_decrypt( pem_iv, 16, buf, len, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 356 else if( enc_alg == MBEDTLS_CIPHER_AES_192_CBC )
Christopher Haster 1:24750b9ad5ef 357 pem_aes_decrypt( pem_iv, 24, buf, len, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 358 else if( enc_alg == MBEDTLS_CIPHER_AES_256_CBC )
Christopher Haster 1:24750b9ad5ef 359 pem_aes_decrypt( pem_iv, 32, buf, len, pwd, pwdlen );
Christopher Haster 1:24750b9ad5ef 360 #endif /* MBEDTLS_AES_C */
Christopher Haster 1:24750b9ad5ef 361
Christopher Haster 1:24750b9ad5ef 362 /*
Christopher Haster 1:24750b9ad5ef 363 * The result will be ASN.1 starting with a SEQUENCE tag, with 1 to 3
Christopher Haster 1:24750b9ad5ef 364 * length bytes (allow 4 to be sure) in all known use cases.
Christopher Haster 1:24750b9ad5ef 365 *
Christopher Haster 1:24750b9ad5ef 366 * Use that as heurisitic to try detecting password mismatchs.
Christopher Haster 1:24750b9ad5ef 367 */
Christopher Haster 1:24750b9ad5ef 368 if( len <= 2 || buf[0] != 0x30 || buf[1] > 0x83 )
Christopher Haster 1:24750b9ad5ef 369 {
Christopher Haster 1:24750b9ad5ef 370 mbedtls_free( buf );
Christopher Haster 1:24750b9ad5ef 371 return( MBEDTLS_ERR_PEM_PASSWORD_MISMATCH );
Christopher Haster 1:24750b9ad5ef 372 }
Christopher Haster 1:24750b9ad5ef 373 #else
Christopher Haster 1:24750b9ad5ef 374 mbedtls_free( buf );
Christopher Haster 1:24750b9ad5ef 375 return( MBEDTLS_ERR_PEM_FEATURE_UNAVAILABLE );
Christopher Haster 1:24750b9ad5ef 376 #endif /* MBEDTLS_MD5_C && MBEDTLS_CIPHER_MODE_CBC &&
Christopher Haster 1:24750b9ad5ef 377 ( MBEDTLS_AES_C || MBEDTLS_DES_C ) */
Christopher Haster 1:24750b9ad5ef 378 }
Christopher Haster 1:24750b9ad5ef 379
Christopher Haster 1:24750b9ad5ef 380 ctx->buf = buf;
Christopher Haster 1:24750b9ad5ef 381 ctx->buflen = len;
Christopher Haster 1:24750b9ad5ef 382
Christopher Haster 1:24750b9ad5ef 383 return( 0 );
Christopher Haster 1:24750b9ad5ef 384 }
Christopher Haster 1:24750b9ad5ef 385
Christopher Haster 1:24750b9ad5ef 386 void mbedtls_pem_free( mbedtls_pem_context *ctx )
Christopher Haster 1:24750b9ad5ef 387 {
Christopher Haster 1:24750b9ad5ef 388 mbedtls_free( ctx->buf );
Christopher Haster 1:24750b9ad5ef 389 mbedtls_free( ctx->info );
Christopher Haster 1:24750b9ad5ef 390
Christopher Haster 1:24750b9ad5ef 391 mbedtls_zeroize( ctx, sizeof( mbedtls_pem_context ) );
Christopher Haster 1:24750b9ad5ef 392 }
Christopher Haster 1:24750b9ad5ef 393 #endif /* MBEDTLS_PEM_PARSE_C */
Christopher Haster 1:24750b9ad5ef 394
Christopher Haster 1:24750b9ad5ef 395 #if defined(MBEDTLS_PEM_WRITE_C)
Christopher Haster 1:24750b9ad5ef 396 int mbedtls_pem_write_buffer( const char *header, const char *footer,
Christopher Haster 1:24750b9ad5ef 397 const unsigned char *der_data, size_t der_len,
Christopher Haster 1:24750b9ad5ef 398 unsigned char *buf, size_t buf_len, size_t *olen )
Christopher Haster 1:24750b9ad5ef 399 {
Christopher Haster 1:24750b9ad5ef 400 int ret;
Christopher Haster 1:24750b9ad5ef 401 unsigned char *encode_buf, *c, *p = buf;
Christopher Haster 1:24750b9ad5ef 402 size_t len = 0, use_len, add_len = 0;
Christopher Haster 1:24750b9ad5ef 403
Christopher Haster 1:24750b9ad5ef 404 mbedtls_base64_encode( NULL, 0, &use_len, der_data, der_len );
Christopher Haster 1:24750b9ad5ef 405 add_len = strlen( header ) + strlen( footer ) + ( use_len / 64 ) + 1;
Christopher Haster 1:24750b9ad5ef 406
Christopher Haster 1:24750b9ad5ef 407 if( use_len + add_len > buf_len )
Christopher Haster 1:24750b9ad5ef 408 {
Christopher Haster 1:24750b9ad5ef 409 *olen = use_len + add_len;
Christopher Haster 1:24750b9ad5ef 410 return( MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL );
Christopher Haster 1:24750b9ad5ef 411 }
Christopher Haster 1:24750b9ad5ef 412
Christopher Haster 1:24750b9ad5ef 413 if( ( encode_buf = mbedtls_calloc( 1, use_len ) ) == NULL )
Christopher Haster 1:24750b9ad5ef 414 return( MBEDTLS_ERR_PEM_ALLOC_FAILED );
Christopher Haster 1:24750b9ad5ef 415
Christopher Haster 1:24750b9ad5ef 416 if( ( ret = mbedtls_base64_encode( encode_buf, use_len, &use_len, der_data,
Christopher Haster 1:24750b9ad5ef 417 der_len ) ) != 0 )
Christopher Haster 1:24750b9ad5ef 418 {
Christopher Haster 1:24750b9ad5ef 419 mbedtls_free( encode_buf );
Christopher Haster 1:24750b9ad5ef 420 return( ret );
Christopher Haster 1:24750b9ad5ef 421 }
Christopher Haster 1:24750b9ad5ef 422
Christopher Haster 1:24750b9ad5ef 423 memcpy( p, header, strlen( header ) );
Christopher Haster 1:24750b9ad5ef 424 p += strlen( header );
Christopher Haster 1:24750b9ad5ef 425 c = encode_buf;
Christopher Haster 1:24750b9ad5ef 426
Christopher Haster 1:24750b9ad5ef 427 while( use_len )
Christopher Haster 1:24750b9ad5ef 428 {
Christopher Haster 1:24750b9ad5ef 429 len = ( use_len > 64 ) ? 64 : use_len;
Christopher Haster 1:24750b9ad5ef 430 memcpy( p, c, len );
Christopher Haster 1:24750b9ad5ef 431 use_len -= len;
Christopher Haster 1:24750b9ad5ef 432 p += len;
Christopher Haster 1:24750b9ad5ef 433 c += len;
Christopher Haster 1:24750b9ad5ef 434 *p++ = '\n';
Christopher Haster 1:24750b9ad5ef 435 }
Christopher Haster 1:24750b9ad5ef 436
Christopher Haster 1:24750b9ad5ef 437 memcpy( p, footer, strlen( footer ) );
Christopher Haster 1:24750b9ad5ef 438 p += strlen( footer );
Christopher Haster 1:24750b9ad5ef 439
Christopher Haster 1:24750b9ad5ef 440 *p++ = '\0';
Christopher Haster 1:24750b9ad5ef 441 *olen = p - buf;
Christopher Haster 1:24750b9ad5ef 442
Christopher Haster 1:24750b9ad5ef 443 mbedtls_free( encode_buf );
Christopher Haster 1:24750b9ad5ef 444 return( 0 );
Christopher Haster 1:24750b9ad5ef 445 }
Christopher Haster 1:24750b9ad5ef 446 #endif /* MBEDTLS_PEM_WRITE_C */
Christopher Haster 1:24750b9ad5ef 447 #endif /* MBEDTLS_PEM_PARSE_C || MBEDTLS_PEM_WRITE_C */