library/cipher.c - security/mbedtls - Rivoreo Source Code Repositories

 /**
  * \file cipher.c
  *
  * \brief Generic cipher wrapper for PolarSSL
  *
  * \author Adriaan de Jong <dejong@fox-it.com>
  *
  *  Copyright (C) 2006-2010, Brainspark B.V.
  *
  *  This file is part of PolarSSL (http://www.polarssl.org)
  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
  *
  *  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 <stdlib.h>

 #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,
 #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,
 #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) */

         0
 };

 const int *cipher_list( void )
 {
     return supported_ciphers;
 }

 const cipher_info_t *cipher_info_from_type( 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;
 #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;
 #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

         default:
             return NULL;
     }
 }

 const cipher_info_t *cipher_info_from_string( const char *cipher_name )
 {
     if( NULL == cipher_name )
         return NULL;

     /* Get the appropriate digest 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 );
 #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 );
 #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
     return NULL;
 }

 int cipher_init_ctx( cipher_context_t *ctx, const cipher_info_t *cipher_info )
 {
     if( NULL == cipher_info || NULL == ctx )
         return 1;

     memset( ctx, 0, sizeof( ctx ) );

     if( NULL == ( ctx->cipher_ctx = cipher_info->ctx_alloc_func() ) )
         return 2;

     ctx->cipher_info = cipher_info;

     return 0;
 }

 int cipher_free_ctx( cipher_context_t *ctx )
 {
     if( ctx == NULL || ctx->cipher_info == NULL )
         return 1;

     ctx->cipher_info->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 1;

     ctx->key_length = key_length;
     ctx->operation = operation;

     if (POLARSSL_ENCRYPT == operation)
         return ctx->cipher_info->setkey_enc_func( ctx->cipher_ctx, key,
                 ctx->key_length );

     if (POLARSSL_DECRYPT == operation)
         return ctx->cipher_info->setkey_dec_func( ctx->cipher_ctx, key,
                 ctx->key_length );

     return 1;
 }

 int cipher_reset( cipher_context_t *ctx, const unsigned char *iv )
 {
     if( NULL == ctx || NULL == ctx->cipher_info || NULL == iv )
         return 1;

     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 )
 {
     size_t copy_len = 0;

     if( NULL == ctx || NULL == ctx->cipher_info || NULL == olen ||
         input == output )
     {
         return 1;
     }

     *olen = 0;

     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 != ctx->cipher_info->cbc_func( ctx->cipher_ctx,
                     ctx->operation, cipher_get_block_size( ctx ), ctx->iv,
                     ctx->unprocessed_data, output) )
             {
                 return 1;
             }

             *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 != ctx->cipher_info->cbc_func( ctx->cipher_ctx,
                     ctx->operation, ilen, ctx->iv, input, output ) )
             {
                 return 1;
             }
             *olen += ilen;
         }

         return 0;
     }

     return 1;
 }

 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, unsigned char input_len,
         size_t *data_len)
 {
     int i = 0;
     unsigned char padding_len = 0;

     if( NULL == input || NULL == data_len )
         return 1;

     padding_len = input[input_len - 1];

     if( padding_len > input_len )
         return 2;

     for( i = input_len - padding_len; i < input_len; i++ )
         if( input[i] != padding_len )
             return 2;

     *data_len = input_len - padding_len;

     return 0;
 }

 int cipher_finish( cipher_context_t *ctx, unsigned char *output, size_t *olen)
 {
     if( NULL == ctx || NULL == ctx->cipher_info || NULL == olen )
         return 1;

     *olen = 0;

     if( POLARSSL_MODE_CBC == ctx->cipher_info->mode )
     {
         if( POLARSSL_ENCRYPT == ctx->operation )
         {
             add_pkcs_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 1;
         }

         /* cipher block */
         if( 0 != ctx->cipher_info->cbc_func( ctx->cipher_ctx, ctx->operation,
                 cipher_get_block_size( ctx ), ctx->iv, ctx->unprocessed_data,
                 output ) )
         {
             return 1;
         }

         /* Set output size for decryption */
         if( POLARSSL_DECRYPT == ctx->operation )
             return get_pkcs_padding( output, cipher_get_block_size( ctx ), olen );

         /* Set output size for encryption */
         *olen = cipher_get_block_size( ctx );
         return 0;
     }

     return 1;
 }

 #if defined(POLARSSL_SELF_TEST)

 #include <stdio.h>

 #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
	/**
	* \file cipher.c
	*
	* \brief Generic cipher wrapper for PolarSSL
	*
	* \author Adriaan de Jong <dejong@fox-it.com>
	*
	* Copyright (C) 2006-2010, Brainspark B.V.
	*
	* This file is part of PolarSSL (http://www.polarssl.org)
	* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
	*
	* 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 <stdlib.h>

	#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,
	#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,
	#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) */

	0
	};

	const int *cipher_list( void )
	{
	return supported_ciphers;
	}

	const cipher_info_t *cipher_info_from_type( 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;
	#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;
	#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

	default:
	return NULL;
	}
	}

	const cipher_info_t cipher_info_from_string( const char cipher_name )
	{
	if( NULL == cipher_name )
	return NULL;

	/* Get the appropriate digest 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 );
	#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 );
	#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
	return NULL;
	}

	int cipher_init_ctx( cipher_context_t ctx, const cipher_info_t cipher_info )
	{
	if( NULL == cipher_info \|\| NULL == ctx )
	return 1;

	memset( ctx, 0, sizeof( ctx ) );

	if( NULL == ( ctx->cipher_ctx = cipher_info->ctx_alloc_func() ) )
	return 2;

	ctx->cipher_info = cipher_info;

	return 0;
	}

	int cipher_free_ctx( cipher_context_t *ctx )
	{
	if( ctx == NULL \|\| ctx->cipher_info == NULL )
	return 1;

	ctx->cipher_info->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 1;

	ctx->key_length = key_length;
	ctx->operation = operation;

	if (POLARSSL_ENCRYPT == operation)
	return ctx->cipher_info->setkey_enc_func( ctx->cipher_ctx, key,
	ctx->key_length );

	if (POLARSSL_DECRYPT == operation)
	return ctx->cipher_info->setkey_dec_func( ctx->cipher_ctx, key,
	ctx->key_length );

	return 1;
	}

	int cipher_reset( cipher_context_t ctx, const unsigned char iv )
	{
	if( NULL == ctx \|\| NULL == ctx->cipher_info \|\| NULL == iv )
	return 1;

	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 )
	{
	size_t copy_len = 0;

	if( NULL == ctx \|\| NULL == ctx->cipher_info \|\| NULL == olen \|\|
	input == output )
	{
	return 1;
	}

	*olen = 0;

	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 != ctx->cipher_info->cbc_func( ctx->cipher_ctx,
	ctx->operation, cipher_get_block_size( ctx ), ctx->iv,
	ctx->unprocessed_data, output) )
	{
	return 1;
	}

	*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 != ctx->cipher_info->cbc_func( ctx->cipher_ctx,
	ctx->operation, ilen, ctx->iv, input, output ) )
	{
	return 1;
	}
	*olen += ilen;
	}

	return 0;
	}

	return 1;
	}

	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, unsigned char input_len,
	size_t *data_len)
	{
	int i = 0;
	unsigned char padding_len = 0;

	if( NULL == input \|\| NULL == data_len )
	return 1;

	padding_len = input[input_len - 1];

	if( padding_len > input_len )
	return 2;

	for( i = input_len - padding_len; i < input_len; i++ )
	if( input[i] != padding_len )
	return 2;

	*data_len = input_len - padding_len;

	return 0;
	}

	int cipher_finish( cipher_context_t ctx, unsigned char output, size_t *olen)
	{
	if( NULL == ctx \|\| NULL == ctx->cipher_info \|\| NULL == olen )
	return 1;

	*olen = 0;

	if( POLARSSL_MODE_CBC == ctx->cipher_info->mode )
	{
	if( POLARSSL_ENCRYPT == ctx->operation )
	{
	add_pkcs_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 1;
	}

	/* cipher block */
	if( 0 != ctx->cipher_info->cbc_func( ctx->cipher_ctx, ctx->operation,
	cipher_get_block_size( ctx ), ctx->iv, ctx->unprocessed_data,
	output ) )
	{
	return 1;
	}

	/* Set output size for decryption */
	if( POLARSSL_DECRYPT == ctx->operation )
	return get_pkcs_padding( output, cipher_get_block_size( ctx ), olen );

	/* Set output size for encryption */
	*olen = cipher_get_block_size( ctx );
	return 0;
	}

	return 1;
	}

	#if defined(POLARSSL_SELF_TEST)

	#include <stdio.h>

	#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