blob: 68c62f528eb59ed86c40086e4261c5824792bcaf [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Cryptographic API.
3 *
4 * SHA1 Secure Hash Algorithm.
5 *
6 * Derived from cryptoapi implementation, adapted for in-place
7 * scatterlist interface.
8 *
9 * Copyright (c) Alan Smithee.
10 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
11 * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
12 *
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms of the GNU General Public License as published by the Free
15 * Software Foundation; either version 2 of the License, or (at your option)
16 * any later version.
17 *
18 */
19#include <linux/init.h>
20#include <linux/module.h>
21#include <linux/mm.h>
22#include <linux/crypto.h>
23#include <linux/cryptohash.h>
Herbert Xu06ace7a2005-10-30 21:25:15 +110024#include <linux/types.h>
Jan Glauber5265eeb2007-10-09 22:43:13 +080025#include <crypto/sha.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <asm/byteorder.h>
27
Linus Torvalds1da177e2005-04-16 15:20:36 -070028struct sha1_ctx {
29 u64 count;
30 u32 state[5];
31 u8 buffer[64];
32};
33
Herbert Xu6c2bb982006-05-16 22:09:29 +100034static void sha1_init(struct crypto_tfm *tfm)
Linus Torvalds1da177e2005-04-16 15:20:36 -070035{
Herbert Xu6c2bb982006-05-16 22:09:29 +100036 struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 static const struct sha1_ctx initstate = {
38 0,
Jan Glauber5265eeb2007-10-09 22:43:13 +080039 { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 { 0, }
41 };
42
43 *sctx = initstate;
44}
45
Herbert Xu6c2bb982006-05-16 22:09:29 +100046static void sha1_update(struct crypto_tfm *tfm, const u8 *data,
47 unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -070048{
Herbert Xu6c2bb982006-05-16 22:09:29 +100049 struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110050 unsigned int partial, done;
Nicolas Pitrecfa8d172005-11-13 10:47:20 +110051 const u8 *src;
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Nicolas Pitrefa9b98f2005-11-13 11:17:33 +110053 partial = sctx->count & 0x3f;
54 sctx->count += len;
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110055 done = 0;
Nicolas Pitrecfa8d172005-11-13 10:47:20 +110056 src = data;
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110058 if ((partial + len) > 63) {
Nicolas Pitrecfa8d172005-11-13 10:47:20 +110059 u32 temp[SHA_WORKSPACE_WORDS];
60
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110061 if (partial) {
Herbert Xubcb0ad22005-12-21 19:01:58 +080062 done = -partial;
63 memcpy(sctx->buffer + partial, data, done + 64);
Nicolas Pitrecfa8d172005-11-13 10:47:20 +110064 src = sctx->buffer;
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 }
Nicolas Pitrecfa8d172005-11-13 10:47:20 +110066
67 do {
68 sha_transform(sctx->state, src, temp);
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110069 done += 64;
70 src = data + done;
71 } while (done + 63 < len);
Nicolas Pitrecfa8d172005-11-13 10:47:20 +110072
73 memset(temp, 0, sizeof(temp));
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110074 partial = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 }
Nicolas Pitre9d70a6c2005-11-13 10:59:54 +110076 memcpy(sctx->buffer + partial, src, len - done);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077}
78
79
80/* Add padding and return the message digest. */
Herbert Xu6c2bb982006-05-16 22:09:29 +100081static void sha1_final(struct crypto_tfm *tfm, u8 *out)
Linus Torvalds1da177e2005-04-16 15:20:36 -070082{
Herbert Xu6c2bb982006-05-16 22:09:29 +100083 struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
Herbert Xu06ace7a2005-10-30 21:25:15 +110084 __be32 *dst = (__be32 *)out;
85 u32 i, index, padlen;
86 __be64 bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 static const u8 padding[64] = { 0x80, };
88
Nicolas Pitrefa9b98f2005-11-13 11:17:33 +110089 bits = cpu_to_be64(sctx->count << 3);
Linus Torvalds1da177e2005-04-16 15:20:36 -070090
91 /* Pad out to 56 mod 64 */
Nicolas Pitrefa9b98f2005-11-13 11:17:33 +110092 index = sctx->count & 0x3f;
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 padlen = (index < 56) ? (56 - index) : ((64+56) - index);
Herbert Xu6c2bb982006-05-16 22:09:29 +100094 sha1_update(tfm, padding, padlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96 /* Append length */
Herbert Xu6c2bb982006-05-16 22:09:29 +100097 sha1_update(tfm, (const u8 *)&bits, sizeof(bits));
Linus Torvalds1da177e2005-04-16 15:20:36 -070098
99 /* Store state in digest */
Herbert Xu06ace7a2005-10-30 21:25:15 +1100100 for (i = 0; i < 5; i++)
101 dst[i] = cpu_to_be32(sctx->state[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
103 /* Wipe context */
104 memset(sctx, 0, sizeof *sctx);
105}
106
107static struct crypto_alg alg = {
108 .cra_name = "sha1",
Michal Ludvigb3be9a62006-07-09 08:59:38 +1000109 .cra_driver_name= "sha1-generic",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 .cra_flags = CRYPTO_ALG_TYPE_DIGEST,
Jan Glauber5265eeb2007-10-09 22:43:13 +0800111 .cra_blocksize = SHA1_BLOCK_SIZE,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 .cra_ctxsize = sizeof(struct sha1_ctx),
113 .cra_module = THIS_MODULE,
Atsushi Nemotoe1147d82006-04-10 08:42:35 +1000114 .cra_alignmask = 3,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 .cra_list = LIST_HEAD_INIT(alg.cra_list),
116 .cra_u = { .digest = {
117 .dia_digestsize = SHA1_DIGEST_SIZE,
118 .dia_init = sha1_init,
119 .dia_update = sha1_update,
120 .dia_final = sha1_final } }
121};
122
123static int __init init(void)
124{
125 return crypto_register_alg(&alg);
126}
127
128static void __exit fini(void)
129{
130 crypto_unregister_alg(&alg);
131}
132
133module_init(init);
134module_exit(fini);
135
136MODULE_LICENSE("GPL");
137MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
Michal Ludvigb3be9a62006-07-09 08:59:38 +1000138
Sebastian Siewiorad5d2782007-10-08 11:45:10 +0800139MODULE_ALIAS("sha1");