1/*
2 * sha512_base.h - core logic for SHA-512 implementations
3 *
4 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <crypto/internal/hash.h>
12#include <crypto/sha.h>
13#include <linux/crypto.h>
14#include <linux/module.h>
15
16#include <asm/unaligned.h>
17
18typedef void (sha512_block_fn)(struct sha512_state *sst, u8 const *src,
19			       int blocks);
20
21static inline int sha384_base_init(struct shash_desc *desc)
22{
23	struct sha512_state *sctx = shash_desc_ctx(desc);
24
25	sctx->state[0] = SHA384_H0;
26	sctx->state[1] = SHA384_H1;
27	sctx->state[2] = SHA384_H2;
28	sctx->state[3] = SHA384_H3;
29	sctx->state[4] = SHA384_H4;
30	sctx->state[5] = SHA384_H5;
31	sctx->state[6] = SHA384_H6;
32	sctx->state[7] = SHA384_H7;
33	sctx->count[0] = sctx->count[1] = 0;
34
35	return 0;
36}
37
38static inline int sha512_base_init(struct shash_desc *desc)
39{
40	struct sha512_state *sctx = shash_desc_ctx(desc);
41
42	sctx->state[0] = SHA512_H0;
43	sctx->state[1] = SHA512_H1;
44	sctx->state[2] = SHA512_H2;
45	sctx->state[3] = SHA512_H3;
46	sctx->state[4] = SHA512_H4;
47	sctx->state[5] = SHA512_H5;
48	sctx->state[6] = SHA512_H6;
49	sctx->state[7] = SHA512_H7;
50	sctx->count[0] = sctx->count[1] = 0;
51
52	return 0;
53}
54
55static inline int sha512_base_do_update(struct shash_desc *desc,
56					const u8 *data,
57					unsigned int len,
58					sha512_block_fn *block_fn)
59{
60	struct sha512_state *sctx = shash_desc_ctx(desc);
61	unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
62
63	sctx->count[0] += len;
64	if (sctx->count[0] < len)
65		sctx->count[1]++;
66
67	if (unlikely((partial + len) >= SHA512_BLOCK_SIZE)) {
68		int blocks;
69
70		if (partial) {
71			int p = SHA512_BLOCK_SIZE - partial;
72
73			memcpy(sctx->buf + partial, data, p);
74			data += p;
75			len -= p;
76
77			block_fn(sctx, sctx->buf, 1);
78		}
79
80		blocks = len / SHA512_BLOCK_SIZE;
81		len %= SHA512_BLOCK_SIZE;
82
83		if (blocks) {
84			block_fn(sctx, data, blocks);
85			data += blocks * SHA512_BLOCK_SIZE;
86		}
87		partial = 0;
88	}
89	if (len)
90		memcpy(sctx->buf + partial, data, len);
91
92	return 0;
93}
94
95static inline int sha512_base_do_finalize(struct shash_desc *desc,
96					  sha512_block_fn *block_fn)
97{
98	const int bit_offset = SHA512_BLOCK_SIZE - sizeof(__be64[2]);
99	struct sha512_state *sctx = shash_desc_ctx(desc);
100	__be64 *bits = (__be64 *)(sctx->buf + bit_offset);
101	unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
102
103	sctx->buf[partial++] = 0x80;
104	if (partial > bit_offset) {
105		memset(sctx->buf + partial, 0x0, SHA512_BLOCK_SIZE - partial);
106		partial = 0;
107
108		block_fn(sctx, sctx->buf, 1);
109	}
110
111	memset(sctx->buf + partial, 0x0, bit_offset - partial);
112	bits[0] = cpu_to_be64(sctx->count[1] << 3 | sctx->count[0] >> 61);
113	bits[1] = cpu_to_be64(sctx->count[0] << 3);
114	block_fn(sctx, sctx->buf, 1);
115
116	return 0;
117}
118
119static inline int sha512_base_finish(struct shash_desc *desc, u8 *out)
120{
121	unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
122	struct sha512_state *sctx = shash_desc_ctx(desc);
123	__be64 *digest = (__be64 *)out;
124	int i;
125
126	for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be64))
127		put_unaligned_be64(sctx->state[i], digest++);
128
129	*sctx = (struct sha512_state){};
130	return 0;
131}
132