src/crypt.c

/* Copyright (c) 2004-2005, Sara Golemon <sarag@libssh2.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms,
 * with or without modification, are permitted provided
 * that the following conditions are met:
 *
 *   Redistributions of source code must retain the above
 *   copyright notice, this list of conditions and the
 *   following disclaimer.
 *
 *   Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 *   Neither the name of the copyright holder nor the names
 *   of any other contributors may be used to endorse or
 *   promote products derived from this software without
 *   specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 */

#include "libssh2_priv.h"
#include <openssl/evp.h>

#ifdef LIBSSH2_CRYPT_NONE
/* {{{ libssh2_crypt_none_crypt
 * Minimalist cipher: VERY secure *wink*
 */
static int libssh2_crypt_none_crypt(LIBSSH2_SESSION *session, unsigned char *buf, void **abstract)
{
	/* Do nothing to the data! */
	return 0;
}
/* }}} */

static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_none = {
	"none",
	8, /* blocksize (SSH2 defines minimum blocksize as 8) */
	0, /* iv_len */
	0, /* secret_len */
	0, /* flags */
	NULL,
	libssh2_crypt_none_crypt,
	NULL
};
#endif

static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_3des_cbc = {
	"3des-cbc",
	8, /* blocksize */
	8, /* initial value length */
	24, /* secret length */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_des_ede3_cbc,
	NULL,
};

#if OPENSSL_VERSION_NUMBER >= 0x00907000L && !defined(OPENSSL_NO_AES)
static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_aes128_cbc = {
	"aes128-cbc",
	16, /* blocksize */
	16, /* initial value length */
	16, /* secret length -- 16*8 == 128bit */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_aes_128_cbc,
	NULL,
};

static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_aes192_cbc = {
	"aes192-cbc",
	16, /* blocksize */
	16, /* initial value length */
	24, /* secret length -- 24*8 == 192bit */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_aes_192_cbc,
	NULL,
};

static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_aes256_cbc = {
	"aes256-cbc",
	16, /* blocksize */
	16, /* initial value length */
	32, /* secret length -- 32*8 == 256bit */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_aes_256_cbc,
	NULL,
};

/* rijndael-cbc@lysator.liu.se == aes256-cbc */
static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_rijndael_cbc_lysator_liu_se = {
	"rijndael-cbc@lysator.liu.se",
	16, /* blocksize */
	16, /* initial value length */
	32, /* secret length -- 32*8 == 256bit */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_aes_256_cbc,
	NULL,
};
#endif /* OPENSSL_VERSION_NUMBER >= 0x00907000L && !defined(OPENSSL_NO_AES)*/

#ifndef OPENSSL_NO_BLOWFISH
static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_blowfish_cbc = {
	"blowfish-cbc",
	8, /* blocksize */
	8, /* initial value length */
	16, /* secret length */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_bf_cbc,
	NULL,
};
#endif /* ! OPENSSL_NO_BLOWFISH */

#ifndef OPENSSL_NO_CAST
static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_cast128_cbc = {
	"cast128-cbc",
	8, /* blocksize */
	8, /* initial value length */
	16, /* secret length */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_cast5_cbc,
	NULL,
};
#endif /* ! OPENSSL_NO_CAST */

#ifndef OPENSSL_NO_RC4
static LIBSSH2_CRYPT_METHOD libssh2_crypt_method_arcfour = {
	"arcfour",
	8, /* blocksize */
	8, /* initial value length */
	16, /* secret length */
	LIBSSH2_CRYPT_METHOD_FLAG_EVP,
	NULL,
	(void*)EVP_rc4,
	NULL,
};
#endif /* ! OPENSSL_NO_RC4 */

static LIBSSH2_CRYPT_METHOD *_libssh2_crypt_methods[] = {
#if OPENSSL_VERSION_NUMBER >= 0x00907000L && !defined(OPENSSL_NO_AES)
	&libssh2_crypt_method_aes256_cbc,
	&libssh2_crypt_method_rijndael_cbc_lysator_liu_se, /* == aes256-cbc */
	&libssh2_crypt_method_aes192_cbc,
	&libssh2_crypt_method_aes128_cbc,
#endif /* OPENSSL_VERSION_NUMBER >= 0x00907000L && !defined(OPENSSL_NO_AES) */
#ifndef OPENSSL_NO_BLOWFISH
	&libssh2_crypt_method_blowfish_cbc,
#endif /* ! OPENSSL_NO_BLOWFISH */
#ifndef OPENSSL_NO_RC4
	&libssh2_crypt_method_arcfour,
#endif /* ! OPENSSL_NO_RC4 */
#ifndef OPENSSL_NO_CAST
	&libssh2_crypt_method_cast128_cbc,
#endif /* ! OPENSSL_NO_CAST */
#ifndef OPENSSL_NO_DES
	&libssh2_crypt_method_3des_cbc,
#endif /* ! OPENSSL_NO_DES */
#ifdef LIBSSH2_CRYPT_NONE
 	&libssh2_crypt_method_none,
#endif
	NULL
};

/* Expose to kex.c */
LIBSSH2_CRYPT_METHOD **libssh2_crypt_methods(void) {
	return _libssh2_crypt_methods;
}