/** * \file cipher.c * * \brief Generic cipher wrapper for PolarSSL * * \author Adriaan de Jong * * Copyright (C) 2006-2013, Brainspark B.V. * * This file is part of PolarSSL (http://www.polarssl.org) * Lead Maintainer: Paul Bakker * * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include "polarssl/config.h" #if defined(POLARSSL_CIPHER_C) #include "polarssl/cipher.h" #include "polarssl/cipher_wrap.h" #include #if defined _MSC_VER && !defined strcasecmp #define strcasecmp _stricmp #endif static const int supported_ciphers[] = { #if defined(POLARSSL_AES_C) POLARSSL_CIPHER_AES_128_CBC, POLARSSL_CIPHER_AES_192_CBC, POLARSSL_CIPHER_AES_256_CBC, #if defined(POLARSSL_CIPHER_MODE_CFB) POLARSSL_CIPHER_AES_128_CFB128, POLARSSL_CIPHER_AES_192_CFB128, POLARSSL_CIPHER_AES_256_CFB128, #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) POLARSSL_CIPHER_AES_128_CTR, POLARSSL_CIPHER_AES_192_CTR, POLARSSL_CIPHER_AES_256_CTR, #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif /* defined(POLARSSL_AES_C) */ #if defined(POLARSSL_CAMELLIA_C) POLARSSL_CIPHER_CAMELLIA_128_CBC, POLARSSL_CIPHER_CAMELLIA_192_CBC, POLARSSL_CIPHER_CAMELLIA_256_CBC, #if defined(POLARSSL_CIPHER_MODE_CFB) POLARSSL_CIPHER_CAMELLIA_128_CFB128, POLARSSL_CIPHER_CAMELLIA_192_CFB128, POLARSSL_CIPHER_CAMELLIA_256_CFB128, #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) POLARSSL_CIPHER_CAMELLIA_128_CTR, POLARSSL_CIPHER_CAMELLIA_192_CTR, POLARSSL_CIPHER_CAMELLIA_256_CTR, #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif /* defined(POLARSSL_CAMELLIA_C) */ #if defined(POLARSSL_DES_C) POLARSSL_CIPHER_DES_CBC, POLARSSL_CIPHER_DES_EDE_CBC, POLARSSL_CIPHER_DES_EDE3_CBC, #endif /* defined(POLARSSL_DES_C) */ #if defined(POLARSSL_BLOWFISH_C) POLARSSL_CIPHER_BLOWFISH_CBC, #if defined(POLARSSL_CIPHER_MODE_CFB) POLARSSL_CIPHER_BLOWFISH_CFB64, #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) POLARSSL_CIPHER_BLOWFISH_CTR, #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif /* defined(POLARSSL_BLOWFISH_C) */ #if defined(POLARSSL_CIPHER_NULL_CIPHER) POLARSSL_CIPHER_NULL, #endif /* defined(POLARSSL_CIPHER_NULL_CIPHER) */ 0 }; const int *cipher_list( void ) { return supported_ciphers; } const cipher_info_t *cipher_info_from_type( const cipher_type_t cipher_type ) { /* Find static cipher information */ switch ( cipher_type ) { #if defined(POLARSSL_AES_C) case POLARSSL_CIPHER_AES_128_CBC: return &aes_128_cbc_info; case POLARSSL_CIPHER_AES_192_CBC: return &aes_192_cbc_info; case POLARSSL_CIPHER_AES_256_CBC: return &aes_256_cbc_info; #if defined(POLARSSL_CIPHER_MODE_CFB) case POLARSSL_CIPHER_AES_128_CFB128: return &aes_128_cfb128_info; case POLARSSL_CIPHER_AES_192_CFB128: return &aes_192_cfb128_info; case POLARSSL_CIPHER_AES_256_CFB128: return &aes_256_cfb128_info; #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) case POLARSSL_CIPHER_AES_128_CTR: return &aes_128_ctr_info; case POLARSSL_CIPHER_AES_192_CTR: return &aes_192_ctr_info; case POLARSSL_CIPHER_AES_256_CTR: return &aes_256_ctr_info; #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #if defined(POLARSSL_GCM_C) case POLARSSL_CIPHER_AES_128_GCM: return &aes_128_gcm_info; case POLARSSL_CIPHER_AES_256_GCM: return &aes_256_gcm_info; #endif /* defined(POLARSSL_GCM_C) */ #endif #if defined(POLARSSL_CAMELLIA_C) case POLARSSL_CIPHER_CAMELLIA_128_CBC: return &camellia_128_cbc_info; case POLARSSL_CIPHER_CAMELLIA_192_CBC: return &camellia_192_cbc_info; case POLARSSL_CIPHER_CAMELLIA_256_CBC: return &camellia_256_cbc_info; #if defined(POLARSSL_CIPHER_MODE_CFB) case POLARSSL_CIPHER_CAMELLIA_128_CFB128: return &camellia_128_cfb128_info; case POLARSSL_CIPHER_CAMELLIA_192_CFB128: return &camellia_192_cfb128_info; case POLARSSL_CIPHER_CAMELLIA_256_CFB128: return &camellia_256_cfb128_info; #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) case POLARSSL_CIPHER_CAMELLIA_128_CTR: return &camellia_128_ctr_info; case POLARSSL_CIPHER_CAMELLIA_192_CTR: return &camellia_192_ctr_info; case POLARSSL_CIPHER_CAMELLIA_256_CTR: return &camellia_256_ctr_info; #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif #if defined(POLARSSL_DES_C) case POLARSSL_CIPHER_DES_CBC: return &des_cbc_info; case POLARSSL_CIPHER_DES_EDE_CBC: return &des_ede_cbc_info; case POLARSSL_CIPHER_DES_EDE3_CBC: return &des_ede3_cbc_info; #endif #if defined(POLARSSL_ARC4_C) case POLARSSL_CIPHER_ARC4_128: return &arc4_128_info; #endif #if defined(POLARSSL_BLOWFISH_C) case POLARSSL_CIPHER_BLOWFISH_CBC: return &blowfish_cbc_info; #if defined(POLARSSL_CIPHER_MODE_CFB) case POLARSSL_CIPHER_BLOWFISH_CFB64: return &blowfish_cfb64_info; #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) case POLARSSL_CIPHER_BLOWFISH_CTR: return &blowfish_ctr_info; #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif #if defined(POLARSSL_CIPHER_NULL_CIPHER) case POLARSSL_CIPHER_NULL: return &null_cipher_info; #endif /* defined(POLARSSL_CIPHER_NULL_CIPHER) */ default: return NULL; } } const cipher_info_t *cipher_info_from_string( const char *cipher_name ) { if( NULL == cipher_name ) return NULL; /* Get the appropriate cipher information */ #if defined(POLARSSL_CAMELLIA_C) if( !strcasecmp( "CAMELLIA-128-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_128_CBC ); if( !strcasecmp( "CAMELLIA-192-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_192_CBC ); if( !strcasecmp( "CAMELLIA-256-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_256_CBC ); #if defined(POLARSSL_CIPHER_MODE_CFB) if( !strcasecmp( "CAMELLIA-128-CFB128", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_128_CFB128 ); if( !strcasecmp( "CAMELLIA-192-CFB128", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_192_CFB128 ); if( !strcasecmp( "CAMELLIA-256-CFB128", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_256_CFB128 ); #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) if( !strcasecmp( "CAMELLIA-128-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_128_CTR ); if( !strcasecmp( "CAMELLIA-192-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_192_CTR ); if( !strcasecmp( "CAMELLIA-256-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_CAMELLIA_256_CTR ); #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif #if defined(POLARSSL_AES_C) if( !strcasecmp( "AES-128-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_128_CBC ); if( !strcasecmp( "AES-192-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_192_CBC ); if( !strcasecmp( "AES-256-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_256_CBC ); #if defined(POLARSSL_CIPHER_MODE_CFB) if( !strcasecmp( "AES-128-CFB128", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_128_CFB128 ); if( !strcasecmp( "AES-192-CFB128", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_192_CFB128 ); if( !strcasecmp( "AES-256-CFB128", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_256_CFB128 ); #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) if( !strcasecmp( "AES-128-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_128_CTR ); if( !strcasecmp( "AES-192-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_192_CTR ); if( !strcasecmp( "AES-256-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_AES_256_CTR ); #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif #if defined(POLARSSL_DES_C) if( !strcasecmp( "DES-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_DES_CBC ); if( !strcasecmp( "DES-EDE-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_DES_EDE_CBC ); if( !strcasecmp( "DES-EDE3-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_DES_EDE3_CBC ); #endif #if defined(POLARSSL_BLOWFISH_C) if( !strcasecmp( "BLOWFISH-CBC", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_BLOWFISH_CBC ); #if defined(POLARSSL_CIPHER_MODE_CFB) if( !strcasecmp( "BLOWFISH-CFB64", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_BLOWFISH_CFB64 ); #endif /* defined(POLARSSL_CIPHER_MODE_CFB) */ #if defined(POLARSSL_CIPHER_MODE_CTR) if( !strcasecmp( "BLOWFISH-CTR", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_BLOWFISH_CTR ); #endif /* defined(POLARSSL_CIPHER_MODE_CTR) */ #endif #if defined(POLARSSL_CIPHER_NULL_CIPHER) if( !strcasecmp( "NULL", cipher_name ) ) return cipher_info_from_type( POLARSSL_CIPHER_NULL ); #endif /* defined(POLARSSL_CIPHER_NULL_CIPHER) */ return NULL; } int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info ) { if( NULL == cipher_info || NULL == ctx ) return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; memset( ctx, 0, sizeof( cipher_context_t ) ); if( NULL == ( ctx->cipher_ctx = cipher_info->base->ctx_alloc_func() ) ) return POLARSSL_ERR_CIPHER_ALLOC_FAILED; ctx->cipher_info = cipher_info; /* * Ignore possible errors caused by a cipher mode that doesn't use padding */ (void) cipher_set_padding_mode( ctx, POLARSSL_PADDING_PKCS7 ); return 0; } int cipher_free_ctx( cipher_context_t *ctx ) { if( ctx == NULL || ctx->cipher_info == NULL ) return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; ctx->cipher_info->base->ctx_free_func( ctx->cipher_ctx ); return 0; } int cipher_setkey( cipher_context_t *ctx, const unsigned char *key, int key_length, const operation_t operation ) { if( NULL == ctx || NULL == ctx->cipher_info ) return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; ctx->key_length = key_length; ctx->operation = operation; #if defined(POLARSSL_CIPHER_NULL_CIPHER) if( ctx->cipher_info->mode == POLARSSL_MODE_NULL ) return 0; #endif /* defined(POLARSSL_CIPHER_NULL_CIPHER) */ /* * For CFB and CTR mode always use the encryption key schedule */ if( POLARSSL_ENCRYPT == operation || POLARSSL_MODE_CFB == ctx->cipher_info->mode || POLARSSL_MODE_CTR == ctx->cipher_info->mode ) { return ctx->cipher_info->base->setkey_enc_func( ctx->cipher_ctx, key, ctx->key_length ); } if( POLARSSL_DECRYPT == operation ) return ctx->cipher_info->base->setkey_dec_func( ctx->cipher_ctx, key, ctx->key_length ); return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; } int cipher_reset( cipher_context_t *ctx, const unsigned char *iv ) { if( NULL == ctx || NULL == ctx->cipher_info || NULL == iv ) return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; ctx->unprocessed_len = 0; memcpy( ctx->iv, iv, cipher_get_iv_size( ctx ) ); return 0; } int cipher_update( cipher_context_t *ctx, const unsigned char *input, size_t ilen, unsigned char *output, size_t *olen ) { int ret; size_t copy_len = 0; *olen = 0; if( NULL == ctx || NULL == ctx->cipher_info || NULL == olen ) { return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; } if( input == output && ( ctx->unprocessed_len != 0 || ilen % cipher_get_block_size( ctx ) ) ) { return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; } #if defined(POLARSSL_CIPHER_NULL_CIPHER) if( ctx->cipher_info->mode == POLARSSL_MODE_NULL ) { *olen = ilen; if( output == input ) return( 0 ); memcpy( output, input, ilen ); return 0; } #endif /* defined(POLARSSL_CIPHER_NULL_CIPHER) */ if( ctx->cipher_info->mode == POLARSSL_MODE_CBC ) { /* * If there is not enough data for a full block, cache it. */ if( ( ctx->operation == POLARSSL_DECRYPT && ilen + ctx->unprocessed_len <= cipher_get_block_size( ctx ) ) || ( ctx->operation == POLARSSL_ENCRYPT && ilen + ctx->unprocessed_len < cipher_get_block_size( ctx ) ) ) { memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ), input, ilen ); ctx->unprocessed_len += ilen; return 0; } /* * Process cached data first */ if( ctx->unprocessed_len != 0 ) { copy_len = cipher_get_block_size( ctx ) - ctx->unprocessed_len; memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ), input, copy_len ); if( 0 != ( ret = ctx->cipher_info->base->cbc_func( ctx->cipher_ctx, ctx->operation, cipher_get_block_size( ctx ), ctx->iv, ctx->unprocessed_data, output ) ) ) { return ret; } *olen += cipher_get_block_size( ctx ); output += cipher_get_block_size( ctx ); ctx->unprocessed_len = 0; input += copy_len; ilen -= copy_len; } /* * Cache final, incomplete block */ if( 0 != ilen ) { copy_len = ilen % cipher_get_block_size( ctx ); if( copy_len == 0 && ctx->operation == POLARSSL_DECRYPT ) copy_len = cipher_get_block_size(ctx); memcpy( ctx->unprocessed_data, &( input[ilen - copy_len] ), copy_len ); ctx->unprocessed_len += copy_len; ilen -= copy_len; } /* * Process remaining full blocks */ if( ilen ) { if( 0 != ( ret = ctx->cipher_info->base->cbc_func( ctx->cipher_ctx, ctx->operation, ilen, ctx->iv, input, output ) ) ) { return ret; } *olen += ilen; } return 0; } #if defined(POLARSSL_CIPHER_MODE_CFB) if( ctx->cipher_info->mode == POLARSSL_MODE_CFB ) { if( 0 != ( ret = ctx->cipher_info->base->cfb_func( ctx->cipher_ctx, ctx->operation, ilen, &ctx->unprocessed_len, ctx->iv, input, output ) ) ) { return ret; } *olen = ilen; return 0; } #endif #if defined(POLARSSL_CIPHER_MODE_CTR) if( ctx->cipher_info->mode == POLARSSL_MODE_CTR ) { if( 0 != ( ret = ctx->cipher_info->base->ctr_func( ctx->cipher_ctx, ilen, &ctx->unprocessed_len, ctx->iv, ctx->unprocessed_data, input, output ) ) ) { return ret; } *olen = ilen; return 0; } #endif return POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE; } static void add_pkcs_padding( unsigned char *output, size_t output_len, size_t data_len ) { size_t padding_len = output_len - data_len; unsigned char i = 0; for( i = 0; i < padding_len; i++ ) output[data_len + i] = (unsigned char) padding_len; } static int get_pkcs_padding( unsigned char *input, size_t input_len, size_t *data_len ) { unsigned int i, padding_len = 0; if( NULL == input || NULL == data_len ) return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; padding_len = input[input_len - 1]; if( padding_len > input_len || padding_len == 0 ) return POLARSSL_ERR_CIPHER_INVALID_PADDING; for( i = input_len - padding_len; i < input_len; i++ ) if( input[i] != padding_len ) return POLARSSL_ERR_CIPHER_INVALID_PADDING; *data_len = input_len - padding_len; return 0; } int cipher_finish( cipher_context_t *ctx, unsigned char *output, size_t *olen) { int ret = 0; if( NULL == ctx || NULL == ctx->cipher_info || NULL == olen ) return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; *olen = 0; if( POLARSSL_MODE_CFB == ctx->cipher_info->mode || POLARSSL_MODE_CTR == ctx->cipher_info->mode || POLARSSL_MODE_NULL == ctx->cipher_info->mode ) { return 0; } if( POLARSSL_MODE_CBC == ctx->cipher_info->mode ) { if( POLARSSL_ENCRYPT == ctx->operation ) { ctx->add_padding( ctx->unprocessed_data, cipher_get_iv_size( ctx ), ctx->unprocessed_len ); } else if ( cipher_get_block_size( ctx ) != ctx->unprocessed_len ) { /* For decrypt operations, expect a full block */ return POLARSSL_ERR_CIPHER_FULL_BLOCK_EXPECTED; } /* cipher block */ if( 0 != ( ret = ctx->cipher_info->base->cbc_func( ctx->cipher_ctx, ctx->operation, cipher_get_block_size( ctx ), ctx->iv, ctx->unprocessed_data, output ) ) ) { return ret; } /* Set output size for decryption */ if( POLARSSL_DECRYPT == ctx->operation ) return ctx->get_padding( output, cipher_get_block_size( ctx ), olen ); /* Set output size for encryption */ *olen = cipher_get_block_size( ctx ); return 0; } return POLARSSL_ERR_CIPHER_FEATURE_UNAVAILABLE; } int cipher_set_padding_mode( cipher_context_t *ctx, cipher_padding_t mode ) { if( NULL == ctx || POLARSSL_MODE_CBC != ctx->cipher_info->mode ) { return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; } if( POLARSSL_PADDING_PKCS7 == mode ) { ctx->add_padding = add_pkcs_padding; ctx->get_padding = get_pkcs_padding; return 0; } return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA; } #if defined(POLARSSL_SELF_TEST) #include #define ASSERT(x) if (!(x)) { \ printf( "failed with %i at %s\n", value, (#x) ); \ return( 1 ); \ } /* * Checkup routine */ int cipher_self_test( int verbose ) { ((void) verbose); return( 0 ); } #endif #endif