diff options
author | Joachim Fritschi <jfritschi@freenet.de> | 2010-06-03 21:02:51 +1000 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2010-06-03 21:02:51 +1000 |
commit | 5b04fc170382195d7d33fd08e3ccc2ad8e50e782 (patch) | |
tree | 47530362afd11dd2637ad5c00e70472fe09e4284 /crypto/twofish.c | |
parent | 0b767f96164b2b27488e3daa722ff16e89d49314 (diff) |
crypto: twofish: Rename twofish to twofish_generic and add an alias
This fixes the broken autoloading of the corresponding twofish assembler
ciphers on x86 and x86_64 if they are available. The module name of the
generic implementation was in conflict with the alias in the assembler
modules. The generic twofish c implementation is renamed to
twofish_generic according to the other algorithms with assembler
implementations and an module alias is added for 'twofish'. You can now
load 'twofish' giving you the best implementation by priority,
'twofish-generic' to get the c implementation or 'twofish-asm' to get
the assembler version of cipher.
Signed-off-by: Joachim Fritschi <jfritschi@freenet.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/twofish.c')
-rw-r--r-- | crypto/twofish.c | 214 |
1 files changed, 0 insertions, 214 deletions
diff --git a/crypto/twofish.c b/crypto/twofish.c deleted file mode 100644 index dfcda231f87..00000000000 --- a/crypto/twofish.c +++ /dev/null @@ -1,214 +0,0 @@ -/* - * Twofish for CryptoAPI - * - * Originally Twofish for GPG - * By Matthew Skala <mskala@ansuz.sooke.bc.ca>, July 26, 1998 - * 256-bit key length added March 20, 1999 - * Some modifications to reduce the text size by Werner Koch, April, 1998 - * Ported to the kerneli patch by Marc Mutz <Marc@Mutz.com> - * Ported to CryptoAPI by Colin Slater <hoho@tacomeat.net> - * - * The original author has disclaimed all copyright interest in this - * code and thus put it in the public domain. The subsequent authors - * have put this under the GNU General Public License. - * - * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 - * USA - * - * This code is a "clean room" implementation, written from the paper - * _Twofish: A 128-Bit Block Cipher_ by Bruce Schneier, John Kelsey, - * Doug Whiting, David Wagner, Chris Hall, and Niels Ferguson, available - * through http://www.counterpane.com/twofish.html - * - * For background information on multiplication in finite fields, used for - * the matrix operations in the key schedule, see the book _Contemporary - * Abstract Algebra_ by Joseph A. Gallian, especially chapter 22 in the - * Third Edition. - */ - -#include <asm/byteorder.h> -#include <crypto/twofish.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/types.h> -#include <linux/errno.h> -#include <linux/crypto.h> -#include <linux/bitops.h> - -/* Macros to compute the g() function in the encryption and decryption - * rounds. G1 is the straight g() function; G2 includes the 8-bit - * rotation for the high 32-bit word. */ - -#define G1(a) \ - (ctx->s[0][(a) & 0xFF]) ^ (ctx->s[1][((a) >> 8) & 0xFF]) \ - ^ (ctx->s[2][((a) >> 16) & 0xFF]) ^ (ctx->s[3][(a) >> 24]) - -#define G2(b) \ - (ctx->s[1][(b) & 0xFF]) ^ (ctx->s[2][((b) >> 8) & 0xFF]) \ - ^ (ctx->s[3][((b) >> 16) & 0xFF]) ^ (ctx->s[0][(b) >> 24]) - -/* Encryption and decryption Feistel rounds. Each one calls the two g() - * macros, does the PHT, and performs the XOR and the appropriate bit - * rotations. The parameters are the round number (used to select subkeys), - * and the four 32-bit chunks of the text. */ - -#define ENCROUND(n, a, b, c, d) \ - x = G1 (a); y = G2 (b); \ - x += y; y += x + ctx->k[2 * (n) + 1]; \ - (c) ^= x + ctx->k[2 * (n)]; \ - (c) = ror32((c), 1); \ - (d) = rol32((d), 1) ^ y - -#define DECROUND(n, a, b, c, d) \ - x = G1 (a); y = G2 (b); \ - x += y; y += x; \ - (d) ^= y + ctx->k[2 * (n) + 1]; \ - (d) = ror32((d), 1); \ - (c) = rol32((c), 1); \ - (c) ^= (x + ctx->k[2 * (n)]) - -/* Encryption and decryption cycles; each one is simply two Feistel rounds - * with the 32-bit chunks re-ordered to simulate the "swap" */ - -#define ENCCYCLE(n) \ - ENCROUND (2 * (n), a, b, c, d); \ - ENCROUND (2 * (n) + 1, c, d, a, b) - -#define DECCYCLE(n) \ - DECROUND (2 * (n) + 1, c, d, a, b); \ - DECROUND (2 * (n), a, b, c, d) - -/* Macros to convert the input and output bytes into 32-bit words, - * and simultaneously perform the whitening step. INPACK packs word - * number n into the variable named by x, using whitening subkey number m. - * OUTUNPACK unpacks word number n from the variable named by x, using - * whitening subkey number m. */ - -#define INPACK(n, x, m) \ - x = le32_to_cpu(src[n]) ^ ctx->w[m] - -#define OUTUNPACK(n, x, m) \ - x ^= ctx->w[m]; \ - dst[n] = cpu_to_le32(x) - - - -/* Encrypt one block. in and out may be the same. */ -static void twofish_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) -{ - struct twofish_ctx *ctx = crypto_tfm_ctx(tfm); - const __le32 *src = (const __le32 *)in; - __le32 *dst = (__le32 *)out; - - /* The four 32-bit chunks of the text. */ - u32 a, b, c, d; - - /* Temporaries used by the round function. */ - u32 x, y; - - /* Input whitening and packing. */ - INPACK (0, a, 0); - INPACK (1, b, 1); - INPACK (2, c, 2); - INPACK (3, d, 3); - - /* Encryption Feistel cycles. */ - ENCCYCLE (0); - ENCCYCLE (1); - ENCCYCLE (2); - ENCCYCLE (3); - ENCCYCLE (4); - ENCCYCLE (5); - ENCCYCLE (6); - ENCCYCLE (7); - - /* Output whitening and unpacking. */ - OUTUNPACK (0, c, 4); - OUTUNPACK (1, d, 5); - OUTUNPACK (2, a, 6); - OUTUNPACK (3, b, 7); - -} - -/* Decrypt one block. in and out may be the same. */ -static void twofish_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) -{ - struct twofish_ctx *ctx = crypto_tfm_ctx(tfm); - const __le32 *src = (const __le32 *)in; - __le32 *dst = (__le32 *)out; - - /* The four 32-bit chunks of the text. */ - u32 a, b, c, d; - - /* Temporaries used by the round function. */ - u32 x, y; - - /* Input whitening and packing. */ - INPACK (0, c, 4); - INPACK (1, d, 5); - INPACK (2, a, 6); - INPACK (3, b, 7); - - /* Encryption Feistel cycles. */ - DECCYCLE (7); - DECCYCLE (6); - DECCYCLE (5); - DECCYCLE (4); - DECCYCLE (3); - DECCYCLE (2); - DECCYCLE (1); - DECCYCLE (0); - - /* Output whitening and unpacking. */ - OUTUNPACK (0, a, 0); - OUTUNPACK (1, b, 1); - OUTUNPACK (2, c, 2); - OUTUNPACK (3, d, 3); - -} - -static struct crypto_alg alg = { - .cra_name = "twofish", - .cra_driver_name = "twofish-generic", - .cra_priority = 100, - .cra_flags = CRYPTO_ALG_TYPE_CIPHER, - .cra_blocksize = TF_BLOCK_SIZE, - .cra_ctxsize = sizeof(struct twofish_ctx), - .cra_alignmask = 3, - .cra_module = THIS_MODULE, - .cra_list = LIST_HEAD_INIT(alg.cra_list), - .cra_u = { .cipher = { - .cia_min_keysize = TF_MIN_KEY_SIZE, - .cia_max_keysize = TF_MAX_KEY_SIZE, - .cia_setkey = twofish_setkey, - .cia_encrypt = twofish_encrypt, - .cia_decrypt = twofish_decrypt } } -}; - -static int __init twofish_mod_init(void) -{ - return crypto_register_alg(&alg); -} - -static void __exit twofish_mod_fini(void) -{ - crypto_unregister_alg(&alg); -} - -module_init(twofish_mod_init); -module_exit(twofish_mod_fini); - -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION ("Twofish Cipher Algorithm"); |