1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
/*
* 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_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("blowfish");
|
