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/sha.h>
21#include <asm/byteorder.h>
22
23void powerpc_sha_transform(u32 *state, const u8 *src);
24
25static int powerpc_sha1_init(struct shash_desc *desc)
26{
27	struct sha1_state *sctx = shash_desc_ctx(desc);
28
29	*sctx = (struct sha1_state){
30		.state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
31	};
32
33	return 0;
34}
35
36static int powerpc_sha1_update(struct shash_desc *desc, const u8 *data,
37			       unsigned int len)
38{
39	struct sha1_state *sctx = shash_desc_ctx(desc);
40	unsigned int partial, done;
41	const u8 *src;
42
43	partial = sctx->count & 0x3f;
44	sctx->count += len;
45	done = 0;
46	src = data;
47
48	if ((partial + len) > 63) {
49
50		if (partial) {
51			done = -partial;
52			memcpy(sctx->buffer + partial, data, done + 64);
53			src = sctx->buffer;
54		}
55
56		do {
57			powerpc_sha_transform(sctx->state, src);
58			done += 64;
59			src = data + done;
60		} while (done + 63 < len);
61
62		partial = 0;
63	}
64	memcpy(sctx->buffer + partial, src, len - done);
65
66	return 0;
67}
68
69
70/* Add padding and return the message digest. */
71static int powerpc_sha1_final(struct shash_desc *desc, u8 *out)
72{
73	struct sha1_state *sctx = shash_desc_ctx(desc);
74	__be32 *dst = (__be32 *)out;
75	u32 i, index, padlen;
76	__be64 bits;
77	static const u8 padding[64] = { 0x80, };
78
79	bits = cpu_to_be64(sctx->count << 3);
80
81	/* Pad out to 56 mod 64 */
82	index = sctx->count & 0x3f;
83	padlen = (index < 56) ? (56 - index) : ((64+56) - index);
84	powerpc_sha1_update(desc, padding, padlen);
85
86	/* Append length */
87	powerpc_sha1_update(desc, (const u8 *)&bits, sizeof(bits));
88
89	/* Store state in digest */
90	for (i = 0; i < 5; i++)
91		dst[i] = cpu_to_be32(sctx->state[i]);
92
93	/* Wipe context */
94	memset(sctx, 0, sizeof *sctx);
95
96	return 0;
97}
98
99static int powerpc_sha1_export(struct shash_desc *desc, void *out)
100{
101	struct sha1_state *sctx = shash_desc_ctx(desc);
102
103	memcpy(out, sctx, sizeof(*sctx));
104	return 0;
105}
106
107static int powerpc_sha1_import(struct shash_desc *desc, const void *in)
108{
109	struct sha1_state *sctx = shash_desc_ctx(desc);
110
111	memcpy(sctx, in, sizeof(*sctx));
112	return 0;
113}
114
115static struct shash_alg alg = {
116	.digestsize	=	SHA1_DIGEST_SIZE,
117	.init		=	powerpc_sha1_init,
118	.update		=	powerpc_sha1_update,
119	.final		=	powerpc_sha1_final,
120	.export		=	powerpc_sha1_export,
121	.import		=	powerpc_sha1_import,
122	.descsize	=	sizeof(struct sha1_state),
123	.statesize	=	sizeof(struct sha1_state),
124	.base		=	{
125		.cra_name	=	"sha1",
126		.cra_driver_name=	"sha1-powerpc",
127		.cra_blocksize	=	SHA1_BLOCK_SIZE,
128		.cra_module	=	THIS_MODULE,
129	}
130};
131
132static int __init sha1_powerpc_mod_init(void)
133{
134	return crypto_register_shash(&alg);
135}
136
137static void __exit sha1_powerpc_mod_fini(void)
138{
139	crypto_unregister_shash(&alg);
140}
141
142module_init(sha1_powerpc_mod_init);
143module_exit(sha1_powerpc_mod_fini);
144
145MODULE_LICENSE("GPL");
146MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
147
148MODULE_ALIAS_CRYPTO("sha1");
149MODULE_ALIAS_CRYPTO("sha1-powerpc");
150