xref: /linux/arch/arm/crypto/sha1_glue.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Cryptographic API.
3  * Glue code for the SHA1 Secure Hash Algorithm assembler implementation
4  *
5  * This file is based on sha1_generic.c and sha1_ssse3_glue.c
6  *
7  * Copyright (c) Alan Smithee.
8  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
9  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
10  * Copyright (c) Mathias Krause <minipli@googlemail.com>
11  *
12  * This program is free software; you can redistribute it and/or modify it
13  * under the terms of the GNU General Public License as published by the Free
14  * Software Foundation; either version 2 of the License, or (at your option)
15  * any later version.
16  *
17  */
18 
19 #include <crypto/internal/hash.h>
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/cryptohash.h>
23 #include <linux/types.h>
24 #include <crypto/sha.h>
25 #include <asm/byteorder.h>
26 
27 struct SHA1_CTX {
28 	uint32_t h0,h1,h2,h3,h4;
29 	u64 count;
30 	u8 data[SHA1_BLOCK_SIZE];
31 };
32 
33 asmlinkage void sha1_block_data_order(struct SHA1_CTX *digest,
34 		const unsigned char *data, unsigned int rounds);
35 
36 
37 static int sha1_init(struct shash_desc *desc)
38 {
39 	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
40 	memset(sctx, 0, sizeof(*sctx));
41 	sctx->h0 = SHA1_H0;
42 	sctx->h1 = SHA1_H1;
43 	sctx->h2 = SHA1_H2;
44 	sctx->h3 = SHA1_H3;
45 	sctx->h4 = SHA1_H4;
46 	return 0;
47 }
48 
49 
50 static int __sha1_update(struct SHA1_CTX *sctx, const u8 *data,
51 			       unsigned int len, unsigned int partial)
52 {
53 	unsigned int done = 0;
54 
55 	sctx->count += len;
56 
57 	if (partial) {
58 		done = SHA1_BLOCK_SIZE - partial;
59 		memcpy(sctx->data + partial, data, done);
60 		sha1_block_data_order(sctx, sctx->data, 1);
61 	}
62 
63 	if (len - done >= SHA1_BLOCK_SIZE) {
64 		const unsigned int rounds = (len - done) / SHA1_BLOCK_SIZE;
65 		sha1_block_data_order(sctx, data + done, rounds);
66 		done += rounds * SHA1_BLOCK_SIZE;
67 	}
68 
69 	memcpy(sctx->data, data + done, len - done);
70 	return 0;
71 }
72 
73 
74 static int sha1_update(struct shash_desc *desc, const u8 *data,
75 			     unsigned int len)
76 {
77 	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
78 	unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
79 	int res;
80 
81 	/* Handle the fast case right here */
82 	if (partial + len < SHA1_BLOCK_SIZE) {
83 		sctx->count += len;
84 		memcpy(sctx->data + partial, data, len);
85 		return 0;
86 	}
87 	res = __sha1_update(sctx, data, len, partial);
88 	return res;
89 }
90 
91 
92 /* Add padding and return the message digest. */
93 static int sha1_final(struct shash_desc *desc, u8 *out)
94 {
95 	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
96 	unsigned int i, index, padlen;
97 	__be32 *dst = (__be32 *)out;
98 	__be64 bits;
99 	static const u8 padding[SHA1_BLOCK_SIZE] = { 0x80, };
100 
101 	bits = cpu_to_be64(sctx->count << 3);
102 
103 	/* Pad out to 56 mod 64 and append length */
104 	index = sctx->count % SHA1_BLOCK_SIZE;
105 	padlen = (index < 56) ? (56 - index) : ((SHA1_BLOCK_SIZE+56) - index);
106 	/* We need to fill a whole block for __sha1_update() */
107 	if (padlen <= 56) {
108 		sctx->count += padlen;
109 		memcpy(sctx->data + index, padding, padlen);
110 	} else {
111 		__sha1_update(sctx, padding, padlen, index);
112 	}
113 	__sha1_update(sctx, (const u8 *)&bits, sizeof(bits), 56);
114 
115 	/* Store state in digest */
116 	for (i = 0; i < 5; i++)
117 		dst[i] = cpu_to_be32(((u32 *)sctx)[i]);
118 
119 	/* Wipe context */
120 	memset(sctx, 0, sizeof(*sctx));
121 	return 0;
122 }
123 
124 
125 static int sha1_export(struct shash_desc *desc, void *out)
126 {
127 	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
128 	memcpy(out, sctx, sizeof(*sctx));
129 	return 0;
130 }
131 
132 
133 static int sha1_import(struct shash_desc *desc, const void *in)
134 {
135 	struct SHA1_CTX *sctx = shash_desc_ctx(desc);
136 	memcpy(sctx, in, sizeof(*sctx));
137 	return 0;
138 }
139 
140 
141 static struct shash_alg alg = {
142 	.digestsize	=	SHA1_DIGEST_SIZE,
143 	.init		=	sha1_init,
144 	.update		=	sha1_update,
145 	.final		=	sha1_final,
146 	.export		=	sha1_export,
147 	.import		=	sha1_import,
148 	.descsize	=	sizeof(struct SHA1_CTX),
149 	.statesize	=	sizeof(struct SHA1_CTX),
150 	.base		=	{
151 		.cra_name	=	"sha1",
152 		.cra_driver_name=	"sha1-asm",
153 		.cra_priority	=	150,
154 		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
155 		.cra_blocksize	=	SHA1_BLOCK_SIZE,
156 		.cra_module	=	THIS_MODULE,
157 	}
158 };
159 
160 
161 static int __init sha1_mod_init(void)
162 {
163 	return crypto_register_shash(&alg);
164 }
165 
166 
167 static void __exit sha1_mod_fini(void)
168 {
169 	crypto_unregister_shash(&alg);
170 }
171 
172 
173 module_init(sha1_mod_init);
174 module_exit(sha1_mod_fini);
175 
176 MODULE_LICENSE("GPL");
177 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm (ARM)");
178 MODULE_ALIAS("sha1");
179 MODULE_AUTHOR("David McCullough <ucdevel@gmail.com>");
180