1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cryptographic API.
4  *
5  * powerpc implementation of the SHA1 Secure Hash Algorithm.
6  *
7  * Derived from cryptoapi implementation, adapted for in-place
8  * scatterlist interface.
9  *
10  * Derived from "crypto/sha1.c"
11  * Copyright (c) Alan Smithee.
12  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
13  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
14  */
15 #include <crypto/internal/hash.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/mm.h>
19 #include <linux/types.h>
20 #include <crypto/sha1.h>
21 #include <crypto/sha1_base.h>
22 #include <asm/byteorder.h>
23 
24 void powerpc_sha_transform(u32 *state, const u8 *src);
25 
powerpc_sha1_update(struct shash_desc * desc,const u8 * data,unsigned int len)26 static int powerpc_sha1_update(struct shash_desc *desc, const u8 *data,
27 			       unsigned int len)
28 {
29 	struct sha1_state *sctx = shash_desc_ctx(desc);
30 	unsigned int partial, done;
31 	const u8 *src;
32 
33 	partial = sctx->count & 0x3f;
34 	sctx->count += len;
35 	done = 0;
36 	src = data;
37 
38 	if ((partial + len) > 63) {
39 
40 		if (partial) {
41 			done = -partial;
42 			memcpy(sctx->buffer + partial, data, done + 64);
43 			src = sctx->buffer;
44 		}
45 
46 		do {
47 			powerpc_sha_transform(sctx->state, src);
48 			done += 64;
49 			src = data + done;
50 		} while (done + 63 < len);
51 
52 		partial = 0;
53 	}
54 	memcpy(sctx->buffer + partial, src, len - done);
55 
56 	return 0;
57 }
58 
59 
60 /* Add padding and return the message digest. */
powerpc_sha1_final(struct shash_desc * desc,u8 * out)61 static int powerpc_sha1_final(struct shash_desc *desc, u8 *out)
62 {
63 	struct sha1_state *sctx = shash_desc_ctx(desc);
64 	__be32 *dst = (__be32 *)out;
65 	u32 i, index, padlen;
66 	__be64 bits;
67 	static const u8 padding[64] = { 0x80, };
68 
69 	bits = cpu_to_be64(sctx->count << 3);
70 
71 	/* Pad out to 56 mod 64 */
72 	index = sctx->count & 0x3f;
73 	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
74 	powerpc_sha1_update(desc, padding, padlen);
75 
76 	/* Append length */
77 	powerpc_sha1_update(desc, (const u8 *)&bits, sizeof(bits));
78 
79 	/* Store state in digest */
80 	for (i = 0; i < 5; i++)
81 		dst[i] = cpu_to_be32(sctx->state[i]);
82 
83 	/* Wipe context */
84 	memset(sctx, 0, sizeof *sctx);
85 
86 	return 0;
87 }
88 
powerpc_sha1_export(struct shash_desc * desc,void * out)89 static int powerpc_sha1_export(struct shash_desc *desc, void *out)
90 {
91 	struct sha1_state *sctx = shash_desc_ctx(desc);
92 
93 	memcpy(out, sctx, sizeof(*sctx));
94 	return 0;
95 }
96 
powerpc_sha1_import(struct shash_desc * desc,const void * in)97 static int powerpc_sha1_import(struct shash_desc *desc, const void *in)
98 {
99 	struct sha1_state *sctx = shash_desc_ctx(desc);
100 
101 	memcpy(sctx, in, sizeof(*sctx));
102 	return 0;
103 }
104 
105 static struct shash_alg alg = {
106 	.digestsize	=	SHA1_DIGEST_SIZE,
107 	.init		=	sha1_base_init,
108 	.update		=	powerpc_sha1_update,
109 	.final		=	powerpc_sha1_final,
110 	.export		=	powerpc_sha1_export,
111 	.import		=	powerpc_sha1_import,
112 	.descsize	=	sizeof(struct sha1_state),
113 	.statesize	=	sizeof(struct sha1_state),
114 	.base		=	{
115 		.cra_name	=	"sha1",
116 		.cra_driver_name=	"sha1-powerpc",
117 		.cra_blocksize	=	SHA1_BLOCK_SIZE,
118 		.cra_module	=	THIS_MODULE,
119 	}
120 };
121 
sha1_powerpc_mod_init(void)122 static int __init sha1_powerpc_mod_init(void)
123 {
124 	return crypto_register_shash(&alg);
125 }
126 
sha1_powerpc_mod_fini(void)127 static void __exit sha1_powerpc_mod_fini(void)
128 {
129 	crypto_unregister_shash(&alg);
130 }
131 
132 module_init(sha1_powerpc_mod_init);
133 module_exit(sha1_powerpc_mod_fini);
134 
135 MODULE_LICENSE("GPL");
136 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
137 
138 MODULE_ALIAS_CRYPTO("sha1");
139 MODULE_ALIAS_CRYPTO("sha1-powerpc");
140