| /* |
| * Cryptographic API. |
| * |
| * Blowfish Cipher Algorithm, by Bruce Schneier. |
| * http://www.counterpane.com/blowfish.html |
| * |
| * Adapted from Kerneli implementation. |
| * |
| * Copyright (c) Herbert Valerio Riedel <hvr@hvrlab.org> |
| * Copyright (c) Kyle McMartin <kyle@debian.org> |
| * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> |
| * |
| * 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. |
| * |
| */ |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/mm.h> |
| #include <asm/byteorder.h> |
| #include <linux/crypto.h> |
| #include <linux/types.h> |
| #include <crypto/blowfish.h> |
| |
| /* |
| * Round loop unrolling macros, S is a pointer to a S-Box array |
| * organized in 4 unsigned longs at a row. |
| */ |
| #define GET32_3(x) (((x) & 0xff)) |
| #define GET32_2(x) (((x) >> (8)) & (0xff)) |
| #define GET32_1(x) (((x) >> (16)) & (0xff)) |
| #define GET32_0(x) (((x) >> (24)) & (0xff)) |
| |
| #define bf_F(x) (((S[GET32_0(x)] + S[256 + GET32_1(x)]) ^ \ |
| S[512 + GET32_2(x)]) + S[768 + GET32_3(x)]) |
| |
| #define ROUND(a, b, n) ({ b ^= P[n]; a ^= bf_F(b); }) |
| |
| static void bf_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) |
| { |
| struct bf_ctx *ctx = crypto_tfm_ctx(tfm); |
| const __be32 *in_blk = (const __be32 *)src; |
| __be32 *const out_blk = (__be32 *)dst; |
| const u32 *P = ctx->p; |
| const u32 *S = ctx->s; |
| u32 yl = be32_to_cpu(in_blk[0]); |
| u32 yr = be32_to_cpu(in_blk[1]); |
| |
| ROUND(yr, yl, 0); |
| ROUND(yl, yr, 1); |
| ROUND(yr, yl, 2); |
| ROUND(yl, yr, 3); |
| ROUND(yr, yl, 4); |
| ROUND(yl, yr, 5); |
| ROUND(yr, yl, 6); |
| ROUND(yl, yr, 7); |
| ROUND(yr, yl, 8); |
| ROUND(yl, yr, 9); |
| ROUND(yr, yl, 10); |
| ROUND(yl, yr, 11); |
| ROUND(yr, yl, 12); |
| ROUND(yl, yr, 13); |
| ROUND(yr, yl, 14); |
| ROUND(yl, yr, 15); |
| |
| yl ^= P[16]; |
| yr ^= P[17]; |
| |
| out_blk[0] = cpu_to_be32(yr); |
| out_blk[1] = cpu_to_be32(yl); |
| } |
| |
| static void bf_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) |
| { |
| struct bf_ctx *ctx = crypto_tfm_ctx(tfm); |
| const __be32 *in_blk = (const __be32 *)src; |
| __be32 *const out_blk = (__be32 *)dst; |
| const u32 *P = ctx->p; |
| const u32 *S = ctx->s; |
| u32 yl = be32_to_cpu(in_blk[0]); |
| u32 yr = be32_to_cpu(in_blk[1]); |
| |
| ROUND(yr, yl, 17); |
| ROUND(yl, yr, 16); |
| ROUND(yr, yl, 15); |
| ROUND(yl, yr, 14); |
| ROUND(yr, yl, 13); |
| ROUND(yl, yr, 12); |
| ROUND(yr, yl, 11); |
| ROUND(yl, yr, 10); |
| ROUND(yr, yl, 9); |
| ROUND(yl, yr, 8); |
| ROUND(yr, yl, 7); |
| ROUND(yl, yr, 6); |
| ROUND(yr, yl, 5); |
| ROUND(yl, yr, 4); |
| ROUND(yr, yl, 3); |
| ROUND(yl, yr, 2); |
| |
| yl ^= P[1]; |
| yr ^= P[0]; |
| |
| out_blk[0] = cpu_to_be32(yr); |
| out_blk[1] = cpu_to_be32(yl); |
| } |
| |
| static struct crypto_alg alg = { |
| .cra_name = "blowfish", |
| .cra_driver_name = "blowfish-generic", |
| .cra_priority = 100, |
| .cra_flags = CRYPTO_ALG_TYPE_CIPHER, |
| .cra_blocksize = BF_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct bf_ctx), |
| .cra_alignmask = 3, |
| .cra_module = THIS_MODULE, |
| .cra_list = LIST_HEAD_INIT(alg.cra_list), |
| .cra_u = { .cipher = { |
| .cia_min_keysize = BF_MIN_KEY_SIZE, |
| .cia_max_keysize = BF_MAX_KEY_SIZE, |
| .cia_setkey = blowfish_setkey, |
| .cia_encrypt = bf_encrypt, |
| .cia_decrypt = bf_decrypt } } |
| }; |
| |
| static int __init blowfish_mod_init(void) |
| { |
| return crypto_register_alg(&alg); |
| } |
| |
| static void __exit blowfish_mod_fini(void) |
| { |
| crypto_unregister_alg(&alg); |
| } |
| |
| module_init(blowfish_mod_init); |
| module_exit(blowfish_mod_fini); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("Blowfish Cipher Algorithm"); |
| MODULE_ALIAS_CRYPTO("blowfish"); |
| MODULE_ALIAS_CRYPTO("blowfish-generic"); |