tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Cryptographic API.
3 *
4 * s390 implementation of the SHA1 Secure Hash Algorithm.
5 *
6 * Derived from cryptoapi implementation, adapted for in-place
7 * scatterlist interface. Originally based on the public domain
8 * implementation written by Steve Reid.
9 *
10 * s390 Version:
11 * Copyright (C) 2003 IBM Deutschland GmbH, IBM Corporation
12 * Author(s): Thomas Spatzier (tspat@de.ibm.com)
13 *
14 * Derived from "crypto/sha1.c"
15 * Copyright (c) Alan Smithee.
16 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
17 * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
18 *
19 * This program is free software; you can redistribute it and/or modify it
20 * under the terms of the GNU General Public License as published by the Free
21 * Software Foundation; either version 2 of the License, or (at your option)
22 * any later version.
23 *
24 */
25#include <linux/init.h>
26#include <linux/module.h>
27#include <linux/mm.h>
28#include <linux/crypto.h>
29#include <asm/scatterlist.h>
30#include <asm/byteorder.h>
31#include "crypt_s390.h"
32
33#define SHA1_DIGEST_SIZE 20
34#define SHA1_BLOCK_SIZE 64
35
36struct crypt_s390_sha1_ctx {
37 u64 count;
38 u32 state[5];
39 u32 buf_len;
40 u8 buffer[2 * SHA1_BLOCK_SIZE];
41};
42
43static void sha1_init(struct crypto_tfm *tfm)
44{
45 struct crypt_s390_sha1_ctx *ctx = crypto_tfm_ctx(tfm);
46 static const u32 initstate[5] = {
47 0x67452301,
48 0xEFCDAB89,
49 0x98BADCFE,
50 0x10325476,
51 0xC3D2E1F0
52 };
53
54 ctx->count = 0;
55 memcpy(ctx->state, &initstate, sizeof(initstate));
56 ctx->buf_len = 0;
57}
58
59static void sha1_update(struct crypto_tfm *tfm, const u8 *data,
60 unsigned int len)
61{
62 struct crypt_s390_sha1_ctx *sctx;
63 long imd_len;
64
65 sctx = crypto_tfm_ctx(tfm);
66 sctx->count += len * 8; //message bit length
67
68 //anything in buffer yet? -> must be completed
69 if (sctx->buf_len && (sctx->buf_len + len) >= SHA1_BLOCK_SIZE) {
70 //complete full block and hash
71 memcpy(sctx->buffer + sctx->buf_len, data,
72 SHA1_BLOCK_SIZE - sctx->buf_len);
73 crypt_s390_kimd(KIMD_SHA_1, sctx->state, sctx->buffer,
74 SHA1_BLOCK_SIZE);
75 data += SHA1_BLOCK_SIZE - sctx->buf_len;
76 len -= SHA1_BLOCK_SIZE - sctx->buf_len;
77 sctx->buf_len = 0;
78 }
79
80 //rest of data contains full blocks?
81 imd_len = len & ~0x3ful;
82 if (imd_len){
83 crypt_s390_kimd(KIMD_SHA_1, sctx->state, data, imd_len);
84 data += imd_len;
85 len -= imd_len;
86 }
87 //anything left? store in buffer
88 if (len){
89 memcpy(sctx->buffer + sctx->buf_len , data, len);
90 sctx->buf_len += len;
91 }
92}
93
94
95static void
96pad_message(struct crypt_s390_sha1_ctx* sctx)
97{
98 int index;
99
100 index = sctx->buf_len;
101 sctx->buf_len = (sctx->buf_len < 56)?
102 SHA1_BLOCK_SIZE:2 * SHA1_BLOCK_SIZE;
103 //start pad with 1
104 sctx->buffer[index] = 0x80;
105 //pad with zeros
106 index++;
107 memset(sctx->buffer + index, 0x00, sctx->buf_len - index);
108 //append length
109 memcpy(sctx->buffer + sctx->buf_len - 8, &sctx->count,
110 sizeof sctx->count);
111}
112
113/* Add padding and return the message digest. */
114static void sha1_final(struct crypto_tfm *tfm, u8 *out)
115{
116 struct crypt_s390_sha1_ctx *sctx = crypto_tfm_ctx(tfm);
117
118 //must perform manual padding
119 pad_message(sctx);
120 crypt_s390_kimd(KIMD_SHA_1, sctx->state, sctx->buffer, sctx->buf_len);
121 //copy digest to out
122 memcpy(out, sctx->state, SHA1_DIGEST_SIZE);
123 /* Wipe context */
124 memset(sctx, 0, sizeof *sctx);
125}
126
127static struct crypto_alg alg = {
128 .cra_name = "sha1",
129 .cra_flags = CRYPTO_ALG_TYPE_DIGEST,
130 .cra_blocksize = SHA1_BLOCK_SIZE,
131 .cra_ctxsize = sizeof(struct crypt_s390_sha1_ctx),
132 .cra_module = THIS_MODULE,
133 .cra_list = LIST_HEAD_INIT(alg.cra_list),
134 .cra_u = { .digest = {
135 .dia_digestsize = SHA1_DIGEST_SIZE,
136 .dia_init = sha1_init,
137 .dia_update = sha1_update,
138 .dia_final = sha1_final } }
139};
140
141static int
142init(void)
143{
144 int ret = -ENOSYS;
145
146 if (crypt_s390_func_available(KIMD_SHA_1)){
147 ret = crypto_register_alg(&alg);
148 if (ret == 0){
149 printk(KERN_INFO "crypt_s390: sha1_s390 loaded.\n");
150 }
151 }
152 return ret;
153}
154
155static void __exit
156fini(void)
157{
158 crypto_unregister_alg(&alg);
159}
160
161module_init(init);
162module_exit(fini);
163
164MODULE_ALIAS("sha1");
165
166MODULE_LICENSE("GPL");
167MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");