src/libpolarssl/pkcs12.c

   1 /*
   2  *  PKCS#12 Personal Information Exchange Syntax
   3  *
   4  *  Copyright (C) 2006-2014, Brainspark B.V.
   5  *
   6  *  This file is part of PolarSSL (http://www.polarssl.org)
   7  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
   8  *
   9  *  All rights reserved.
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or
  14  *  (at your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *  GNU General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with this program; if not, write to the Free Software Foundation, Inc.,
  23  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  24  */
  25 /*
  26  *  The PKCS #12 Personal Information Exchange Syntax Standard v1.1
  27  *
  28  *  http://www.rsa.com/rsalabs/pkcs/files/h11301-wp-pkcs-12v1-1-personal-information-exchange-syntax.pdf
  29  *  ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1-1.asn
  30  */
  31
  32 #if !defined(POLARSSL_CONFIG_FILE)
  33 #include "config.h"
  34 #else
  35 #include POLARSSL_CONFIG_FILE
  36 #endif
  37
  38 #if defined(POLARSSL_PKCS12_C)
  39
  40 #include "pkcs12.h"
  41 #include "asn1.h"
  42 #include "cipher.h"
  43
  44 #if defined(POLARSSL_ARC4_C)
  45 #include "arc4.h"
  46 #endif
  47
  48 #if defined(POLARSSL_DES_C)
  49 #include "des.h"
  50 #endif
  51
  52 static int pkcs12_parse_pbe_params( asn1_buf *params,
  53                                     asn1_buf *salt, int *iterations )
  54 {
  55     int ret;
  56     unsigned char **p = &params->p;
  57     const unsigned char *end = params->p + params->len;
  58
  59     /*
  60      *  pkcs-12PbeParams ::= SEQUENCE {
  61      *    salt          OCTET STRING,
  62      *    iterations    INTEGER
  63      *  }
  64      *
  65      */
  66     if( params->tag != ( ASN1_CONSTRUCTED | ASN1_SEQUENCE ) )
  67         return( POLARSSL_ERR_PKCS12_PBE_INVALID_FORMAT +
  68                 POLARSSL_ERR_ASN1_UNEXPECTED_TAG );
  69
  70     if( ( ret = asn1_get_tag( p, end, &salt->len, ASN1_OCTET_STRING ) ) != 0 )
  71         return( POLARSSL_ERR_PKCS12_PBE_INVALID_FORMAT + ret );
  72
  73     salt->p = *p;
  74     *p += salt->len;
  75
  76     if( ( ret = asn1_get_int( p, end, iterations ) ) != 0 )
  77         return( POLARSSL_ERR_PKCS12_PBE_INVALID_FORMAT + ret );
  78
  79     if( *p != end )
  80         return( POLARSSL_ERR_PKCS12_PBE_INVALID_FORMAT +
  81                 POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
  82
  83     return( 0 );
  84 }
  85
  86 static int pkcs12_pbe_derive_key_iv( asn1_buf *pbe_params, md_type_t md_type,
  87                                      const unsigned char *pwd,  size_t pwdlen,
  88                                      unsigned char *key, size_t keylen,
  89                                      unsigned char *iv,  size_t ivlen )
  90 {
  91     int ret, iterations;
  92     asn1_buf salt;
  93     size_t i;
  94     unsigned char unipwd[258];
  95
  96     memset(&salt, 0, sizeof(asn1_buf));
  97     memset(&unipwd, 0, sizeof(unipwd));
  98
  99     if( ( ret = pkcs12_parse_pbe_params( pbe_params, &salt,
 100                                          &iterations ) ) != 0 )
 101         return( ret );
 102
 103     for(i = 0; i < pwdlen; i++)
 104         unipwd[i * 2 + 1] = pwd[i];
 105
 106     if( ( ret = pkcs12_derivation( key, keylen, unipwd, pwdlen * 2 + 2,
 107                                    salt.p, salt.len, md_type,
 108                                    PKCS12_DERIVE_KEY, iterations ) ) != 0 )
 109     {
 110         return( ret );
 111     }
 112
 113     if( iv == NULL || ivlen == 0 )
 114         return( 0 );
 115
 116     if( ( ret = pkcs12_derivation( iv, ivlen, unipwd, pwdlen * 2 + 2,
 117                                    salt.p, salt.len, md_type,
 118                                    PKCS12_DERIVE_IV, iterations ) ) != 0 )
 119     {
 120         return( ret );
 121     }
 122     return( 0 );
 123 }
 124
 125 int pkcs12_pbe_sha1_rc4_128( asn1_buf *pbe_params, int mode,
 126                              const unsigned char *pwd,  size_t pwdlen,
 127                              const unsigned char *data, size_t len,
 128                              unsigned char *output )
 129 {
 130 #if !defined(POLARSSL_ARC4_C)
 131     ((void) pbe_params);
 132     ((void) mode);
 133     ((void) pwd);
 134     ((void) pwdlen);
 135     ((void) data);
 136     ((void) len);
 137     ((void) output);
 138     return( POLARSSL_ERR_PKCS12_FEATURE_UNAVAILABLE );
 139 #else
 140     int ret;
 141     unsigned char key[16];
 142     arc4_context ctx;
 143     ((void) mode);
 144
 145     if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, POLARSSL_MD_SHA1,
 146                                           pwd, pwdlen,
 147                                           key, 16, NULL, 0 ) ) != 0 )
 148     {
 149         return( ret );
 150     }
 151
 152     arc4_setup( &ctx, key, 16 );
 153     if( ( ret = arc4_crypt( &ctx, len, data, output ) ) != 0 )
 154         return( ret );
 155
 156     return( 0 );
 157 #endif /* POLARSSL_ARC4_C */
 158 }
 159
 160 int pkcs12_pbe( asn1_buf *pbe_params, int mode,
 161                 cipher_type_t cipher_type, md_type_t md_type,
 162                 const unsigned char *pwd,  size_t pwdlen,
 163                 const unsigned char *data, size_t len,
 164                 unsigned char *output )
 165 {
 166     int ret, keylen = 0;
 167     unsigned char key[32];
 168     unsigned char iv[16];
 169     const cipher_info_t *cipher_info;
 170     cipher_context_t cipher_ctx;
 171     size_t olen = 0;
 172
 173     cipher_info = cipher_info_from_type( cipher_type );
 174     if( cipher_info == NULL )
 175         return( POLARSSL_ERR_PKCS12_FEATURE_UNAVAILABLE );
 176
 177     keylen = cipher_info->key_length / 8;
 178
 179     if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, md_type, pwd, pwdlen,
 180                                           key, keylen,
 181                                           iv, cipher_info->iv_size ) ) != 0 )
 182     {
 183         return( ret );
 184     }
 185
 186     if( ( ret = cipher_init_ctx( &cipher_ctx, cipher_info ) ) != 0 )
 187         goto exit;
 188
 189     if( ( ret = cipher_setkey( &cipher_ctx, key, 8 * keylen, mode ) ) != 0 )
 190         goto exit;
 191
 192     if( ( ret = cipher_set_iv( &cipher_ctx, iv, cipher_info->iv_size ) ) != 0 )
 193         goto exit;
 194
 195     if( ( ret = cipher_reset( &cipher_ctx ) ) != 0 )
 196         goto exit;
 197
 198     if( ( ret = cipher_update( &cipher_ctx, data, len,
 199                                 output, &olen ) ) != 0 )
 200     {
 201         goto exit;
 202     }
 203
 204     if( ( ret = cipher_finish( &cipher_ctx, output + olen, &olen ) ) != 0 )
 205         ret = POLARSSL_ERR_PKCS12_PASSWORD_MISMATCH;
 206
 207 exit:
 208     cipher_free_ctx( &cipher_ctx );
 209
 210     return( ret );
 211 }
 212
 213 static void pkcs12_fill_buffer( unsigned char *data, size_t data_len,
 214                                 const unsigned char *filler, size_t fill_len )
 215 {
 216     unsigned char *p = data;
 217     size_t use_len;
 218
 219     while( data_len > 0 )
 220     {
 221         use_len = ( data_len > fill_len ) ? fill_len : data_len;
 222         memcpy( p, filler, use_len );
 223         p += use_len;
 224         data_len -= use_len;
 225     }
 226 }
 227
 228 int pkcs12_derivation( unsigned char *data, size_t datalen,
 229                        const unsigned char *pwd, size_t pwdlen,
 230                        const unsigned char *salt, size_t saltlen,
 231                        md_type_t md_type, int id, int iterations )
 232 {
 233     int ret;
 234     unsigned int j;
 235
 236     unsigned char diversifier[128];
 237     unsigned char salt_block[128], pwd_block[128], hash_block[128];
 238     unsigned char hash_output[POLARSSL_MD_MAX_SIZE];
 239     unsigned char *p;
 240     unsigned char c;
 241
 242     size_t hlen, use_len, v, i;
 243
 244     const md_info_t *md_info;
 245     md_context_t md_ctx;
 246
 247     // This version only allows max of 64 bytes of password or salt
 248     if( datalen > 128 || pwdlen > 64 || saltlen > 64 )
 249         return( POLARSSL_ERR_PKCS12_BAD_INPUT_DATA );
 250
 251     md_info = md_info_from_type( md_type );
 252     if( md_info == NULL )
 253         return( POLARSSL_ERR_PKCS12_FEATURE_UNAVAILABLE );
 254
 255     if ( ( ret = md_init_ctx( &md_ctx, md_info ) ) != 0 )
 256         return( ret );
 257     hlen = md_get_size( md_info );
 258
 259     if( hlen <= 32 )
 260         v = 64;
 261     else
 262         v = 128;
 263
 264     memset( diversifier, (unsigned char) id, v );
 265
 266     pkcs12_fill_buffer( salt_block, v, salt, saltlen );
 267     pkcs12_fill_buffer( pwd_block,  v, pwd,  pwdlen  );
 268
 269     p = data;
 270     while( datalen > 0 )
 271     {
 272         // Calculate hash( diversifier || salt_block || pwd_block )
 273         if( ( ret = md_starts( &md_ctx ) ) != 0 )
 274             goto exit;
 275
 276         if( ( ret = md_update( &md_ctx, diversifier, v ) ) != 0 )
 277             goto exit;
 278
 279         if( ( ret = md_update( &md_ctx, salt_block, v ) ) != 0 )
 280             goto exit;
 281
 282         if( ( ret = md_update( &md_ctx, pwd_block, v ) ) != 0 )
 283             goto exit;
 284
 285         if( ( ret = md_finish( &md_ctx, hash_output ) ) != 0 )
 286             goto exit;
 287
 288         // Perform remaining ( iterations - 1 ) recursive hash calculations
 289         for( i = 1; i < (size_t) iterations; i++ )
 290         {
 291             if( ( ret = md( md_info, hash_output, hlen, hash_output ) ) != 0 )
 292                 goto exit;
 293         }
 294
 295         use_len = ( datalen > hlen ) ? hlen : datalen;
 296         memcpy( p, hash_output, use_len );
 297         datalen -= use_len;
 298         p += use_len;
 299
 300         if( datalen == 0 )
 301             break;
 302
 303         // Concatenating copies of hash_output into hash_block (B)
 304         pkcs12_fill_buffer( hash_block, v, hash_output, hlen );
 305
 306         // B += 1
 307         for( i = v; i > 0; i-- )
 308             if( ++hash_block[i - 1] != 0 )
 309                 break;
 310
 311         // salt_block += B
 312         c = 0;
 313         for( i = v; i > 0; i-- )
 314         {
 315             j = salt_block[i - 1] + hash_block[i - 1] + c;
 316             c = (unsigned char) (j >> 8);
 317             salt_block[i - 1] = j & 0xFF;
 318         }
 319
 320         // pwd_block  += B
 321         c = 0;
 322         for( i = v; i > 0; i-- )
 323         {
 324             j = pwd_block[i - 1] + hash_block[i - 1] + c;
 325             c = (unsigned char) (j >> 8);
 326             pwd_block[i - 1] = j & 0xFF;
 327         }
 328     }
 329
 330     ret = 0;
 331
 332 exit:
 333     md_free_ctx( &md_ctx );
 334
 335     return( ret );
 336 }
 337
 338 #endif /* POLARSSL_PKCS12_C */