xref: /linux/arch/x86/crypto/twofish_glue.c (revision 15e7b4452b72ae890f2fcb027b4c4fa63a1c9a7a)
1*15e7b445SSebastian Siewior /*
2*15e7b445SSebastian Siewior  * Glue Code for assembler optimized version of TWOFISH
3*15e7b445SSebastian Siewior  *
4*15e7b445SSebastian Siewior  * Originally Twofish for GPG
5*15e7b445SSebastian Siewior  * By Matthew Skala <mskala@ansuz.sooke.bc.ca>, July 26, 1998
6*15e7b445SSebastian Siewior  * 256-bit key length added March 20, 1999
7*15e7b445SSebastian Siewior  * Some modifications to reduce the text size by Werner Koch, April, 1998
8*15e7b445SSebastian Siewior  * Ported to the kerneli patch by Marc Mutz <Marc@Mutz.com>
9*15e7b445SSebastian Siewior  * Ported to CryptoAPI by Colin Slater <hoho@tacomeat.net>
10*15e7b445SSebastian Siewior  *
11*15e7b445SSebastian Siewior  * The original author has disclaimed all copyright interest in this
12*15e7b445SSebastian Siewior  * code and thus put it in the public domain. The subsequent authors
13*15e7b445SSebastian Siewior  * have put this under the GNU General Public License.
14*15e7b445SSebastian Siewior  *
15*15e7b445SSebastian Siewior  * This program is free software; you can redistribute it and/or modify
16*15e7b445SSebastian Siewior  * it under the terms of the GNU General Public License as published by
17*15e7b445SSebastian Siewior  * the Free Software Foundation; either version 2 of the License, or
18*15e7b445SSebastian Siewior  * (at your option) any later version.
19*15e7b445SSebastian Siewior  *
20*15e7b445SSebastian Siewior  * This program is distributed in the hope that it will be useful,
21*15e7b445SSebastian Siewior  * but WITHOUT ANY WARRANTY; without even the implied warranty of
22*15e7b445SSebastian Siewior  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23*15e7b445SSebastian Siewior  * GNU General Public License for more details.
24*15e7b445SSebastian Siewior  *
25*15e7b445SSebastian Siewior  * You should have received a copy of the GNU General Public License
26*15e7b445SSebastian Siewior  * along with this program; if not, write to the Free Software
27*15e7b445SSebastian Siewior  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
28*15e7b445SSebastian Siewior  * USA
29*15e7b445SSebastian Siewior  *
30*15e7b445SSebastian Siewior  * This code is a "clean room" implementation, written from the paper
31*15e7b445SSebastian Siewior  * _Twofish: A 128-Bit Block Cipher_ by Bruce Schneier, John Kelsey,
32*15e7b445SSebastian Siewior  * Doug Whiting, David Wagner, Chris Hall, and Niels Ferguson, available
33*15e7b445SSebastian Siewior  * through http://www.counterpane.com/twofish.html
34*15e7b445SSebastian Siewior  *
35*15e7b445SSebastian Siewior  * For background information on multiplication in finite fields, used for
36*15e7b445SSebastian Siewior  * the matrix operations in the key schedule, see the book _Contemporary
37*15e7b445SSebastian Siewior  * Abstract Algebra_ by Joseph A. Gallian, especially chapter 22 in the
38*15e7b445SSebastian Siewior  * Third Edition.
39*15e7b445SSebastian Siewior  */
40*15e7b445SSebastian Siewior 
41*15e7b445SSebastian Siewior #include <crypto/twofish.h>
42*15e7b445SSebastian Siewior #include <linux/crypto.h>
43*15e7b445SSebastian Siewior #include <linux/init.h>
44*15e7b445SSebastian Siewior #include <linux/module.h>
45*15e7b445SSebastian Siewior #include <linux/types.h>
46*15e7b445SSebastian Siewior 
47*15e7b445SSebastian Siewior asmlinkage void twofish_enc_blk(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
48*15e7b445SSebastian Siewior asmlinkage void twofish_dec_blk(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
49*15e7b445SSebastian Siewior 
50*15e7b445SSebastian Siewior static void twofish_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
51*15e7b445SSebastian Siewior {
52*15e7b445SSebastian Siewior 	twofish_enc_blk(tfm, dst, src);
53*15e7b445SSebastian Siewior }
54*15e7b445SSebastian Siewior 
55*15e7b445SSebastian Siewior static void twofish_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
56*15e7b445SSebastian Siewior {
57*15e7b445SSebastian Siewior 	twofish_dec_blk(tfm, dst, src);
58*15e7b445SSebastian Siewior }
59*15e7b445SSebastian Siewior 
60*15e7b445SSebastian Siewior static struct crypto_alg alg = {
61*15e7b445SSebastian Siewior 	.cra_name		=	"twofish",
62*15e7b445SSebastian Siewior 	.cra_driver_name	=	"twofish-asm",
63*15e7b445SSebastian Siewior 	.cra_priority		=	200,
64*15e7b445SSebastian Siewior 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
65*15e7b445SSebastian Siewior 	.cra_blocksize		=	TF_BLOCK_SIZE,
66*15e7b445SSebastian Siewior 	.cra_ctxsize		=	sizeof(struct twofish_ctx),
67*15e7b445SSebastian Siewior 	.cra_alignmask		=	3,
68*15e7b445SSebastian Siewior 	.cra_module		=	THIS_MODULE,
69*15e7b445SSebastian Siewior 	.cra_list		=	LIST_HEAD_INIT(alg.cra_list),
70*15e7b445SSebastian Siewior 	.cra_u			=	{
71*15e7b445SSebastian Siewior 		.cipher = {
72*15e7b445SSebastian Siewior 			.cia_min_keysize	=	TF_MIN_KEY_SIZE,
73*15e7b445SSebastian Siewior 			.cia_max_keysize	=	TF_MAX_KEY_SIZE,
74*15e7b445SSebastian Siewior 			.cia_setkey		=	twofish_setkey,
75*15e7b445SSebastian Siewior 			.cia_encrypt		=	twofish_encrypt,
76*15e7b445SSebastian Siewior 			.cia_decrypt		=	twofish_decrypt
77*15e7b445SSebastian Siewior 		}
78*15e7b445SSebastian Siewior 	}
79*15e7b445SSebastian Siewior };
80*15e7b445SSebastian Siewior 
81*15e7b445SSebastian Siewior static int __init init(void)
82*15e7b445SSebastian Siewior {
83*15e7b445SSebastian Siewior 	return crypto_register_alg(&alg);
84*15e7b445SSebastian Siewior }
85*15e7b445SSebastian Siewior 
86*15e7b445SSebastian Siewior static void __exit fini(void)
87*15e7b445SSebastian Siewior {
88*15e7b445SSebastian Siewior 	crypto_unregister_alg(&alg);
89*15e7b445SSebastian Siewior }
90*15e7b445SSebastian Siewior 
91*15e7b445SSebastian Siewior module_init(init);
92*15e7b445SSebastian Siewior module_exit(fini);
93*15e7b445SSebastian Siewior 
94*15e7b445SSebastian Siewior MODULE_LICENSE("GPL");
95*15e7b445SSebastian Siewior MODULE_DESCRIPTION ("Twofish Cipher Algorithm, asm optimized");
96*15e7b445SSebastian Siewior MODULE_ALIAS("twofish");
97*15e7b445SSebastian Siewior MODULE_ALIAS("twofish-asm");
98