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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Cryptographic API.4 *5 * Blowfish Cipher Algorithm, by Bruce Schneier.6 * http://www.counterpane.com/blowfish.html7 *8 * Adapted from Kerneli implementation.9 *10 * Copyright (c) Herbert Valerio Riedel <hvr@hvrlab.org>11 * Copyright (c) Kyle McMartin <kyle@debian.org>12 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>13 */14 15#include <crypto/algapi.h>16#include <linux/init.h>17#include <linux/module.h>18#include <linux/mm.h>19#include <linux/unaligned.h>20#include <linux/types.h>21#include <crypto/blowfish.h>22 23/*24 * Round loop unrolling macros, S is a pointer to a S-Box array25 * organized in 4 unsigned longs at a row.26 */27#define GET32_3(x) (((x) & 0xff))28#define GET32_2(x) (((x) >> (8)) & (0xff))29#define GET32_1(x) (((x) >> (16)) & (0xff))30#define GET32_0(x) (((x) >> (24)) & (0xff))31 32#define bf_F(x) (((S[GET32_0(x)] + S[256 + GET32_1(x)]) ^ \33 S[512 + GET32_2(x)]) + S[768 + GET32_3(x)])34 35#define ROUND(a, b, n) ({ b ^= P[n]; a ^= bf_F(b); })36 37static void bf_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)38{39 struct bf_ctx *ctx = crypto_tfm_ctx(tfm);40 const u32 *P = ctx->p;41 const u32 *S = ctx->s;42 u32 yl = get_unaligned_be32(src);43 u32 yr = get_unaligned_be32(src + 4);44 45 ROUND(yr, yl, 0);46 ROUND(yl, yr, 1);47 ROUND(yr, yl, 2);48 ROUND(yl, yr, 3);49 ROUND(yr, yl, 4);50 ROUND(yl, yr, 5);51 ROUND(yr, yl, 6);52 ROUND(yl, yr, 7);53 ROUND(yr, yl, 8);54 ROUND(yl, yr, 9);55 ROUND(yr, yl, 10);56 ROUND(yl, yr, 11);57 ROUND(yr, yl, 12);58 ROUND(yl, yr, 13);59 ROUND(yr, yl, 14);60 ROUND(yl, yr, 15);61 62 yl ^= P[16];63 yr ^= P[17];64 65 put_unaligned_be32(yr, dst);66 put_unaligned_be32(yl, dst + 4);67}68 69static void bf_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)70{71 struct bf_ctx *ctx = crypto_tfm_ctx(tfm);72 const u32 *P = ctx->p;73 const u32 *S = ctx->s;74 u32 yl = get_unaligned_be32(src);75 u32 yr = get_unaligned_be32(src + 4);76 77 ROUND(yr, yl, 17);78 ROUND(yl, yr, 16);79 ROUND(yr, yl, 15);80 ROUND(yl, yr, 14);81 ROUND(yr, yl, 13);82 ROUND(yl, yr, 12);83 ROUND(yr, yl, 11);84 ROUND(yl, yr, 10);85 ROUND(yr, yl, 9);86 ROUND(yl, yr, 8);87 ROUND(yr, yl, 7);88 ROUND(yl, yr, 6);89 ROUND(yr, yl, 5);90 ROUND(yl, yr, 4);91 ROUND(yr, yl, 3);92 ROUND(yl, yr, 2);93 94 yl ^= P[1];95 yr ^= P[0];96 97 put_unaligned_be32(yr, dst);98 put_unaligned_be32(yl, dst + 4);99}100 101static struct crypto_alg alg = {102 .cra_name = "blowfish",103 .cra_driver_name = "blowfish-generic",104 .cra_priority = 100,105 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,106 .cra_blocksize = BF_BLOCK_SIZE,107 .cra_ctxsize = sizeof(struct bf_ctx),108 .cra_module = THIS_MODULE,109 .cra_u = { .cipher = {110 .cia_min_keysize = BF_MIN_KEY_SIZE,111 .cia_max_keysize = BF_MAX_KEY_SIZE,112 .cia_setkey = blowfish_setkey,113 .cia_encrypt = bf_encrypt,114 .cia_decrypt = bf_decrypt } }115};116 117static int __init blowfish_mod_init(void)118{119 return crypto_register_alg(&alg);120}121 122static void __exit blowfish_mod_fini(void)123{124 crypto_unregister_alg(&alg);125}126 127subsys_initcall(blowfish_mod_init);128module_exit(blowfish_mod_fini);129 130MODULE_LICENSE("GPL");131MODULE_DESCRIPTION("Blowfish Cipher Algorithm");132MODULE_ALIAS_CRYPTO("blowfish");133MODULE_ALIAS_CRYPTO("blowfish-generic");134