1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * sha1_base.h - core logic for SHA-1 implementations
4 *
5 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
6 */
7
8 #ifndef _CRYPTO_SHA1_BASE_H
9 #define _CRYPTO_SHA1_BASE_H
10
11 #include <crypto/internal/hash.h>
12 #include <crypto/sha1.h>
13 #include <linux/crypto.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16
17 #include <asm/unaligned.h>
18
19 typedef void (sha1_block_fn)(struct sha1_state *sst, u8 const *src, int blocks);
20
21 static inline int sha1_base_init(struct shash_desc *desc)
22 {
23 struct sha1_state *sctx = shash_desc_ctx(desc);
24
25 sctx->state[0] = SHA1_H0;
26 sctx->state[1] = SHA1_H1;
27 sctx->state[2] = SHA1_H2;
28 sctx->state[3] = SHA1_H3;
29 sctx->state[4] = SHA1_H4;
30 sctx->count = 0;
31
32 return 0;
33 }
34
35 static inline int sha1_base_do_update(struct shash_desc *desc,
36 const u8 *data,
37 unsigned int len,
38 sha1_block_fn *block_fn)
39 {
40 struct sha1_state *sctx = shash_desc_ctx(desc);
41 unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
42
43 sctx->count += len;
44
45 if (unlikely((partial + len) >= SHA1_BLOCK_SIZE)) {
46 int blocks;
47
48 if (partial) {
49 int p = SHA1_BLOCK_SIZE - partial;
50
51 memcpy(sctx->buffer + partial, data, p);
52 data += p;
53 len -= p;
54
55 block_fn(sctx, sctx->buffer, 1);
56 }
57
58 blocks = len / SHA1_BLOCK_SIZE;
59 len %= SHA1_BLOCK_SIZE;
60
61 if (blocks) {
62 block_fn(sctx, data, blocks);
63 data += blocks * SHA1_BLOCK_SIZE;
64 }
65 partial = 0;
66 }
67 if (len)
68 memcpy(sctx->buffer + partial, data, len);
69
70 return 0;
71 }
72
73 static inline int sha1_base_do_finalize(struct shash_desc *desc,
74 sha1_block_fn *block_fn)
75 {
76 const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64);
77 struct sha1_state *sctx = shash_desc_ctx(desc);
78 __be64 *bits = (__be64 *)(sctx->buffer + bit_offset);
79 unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
80
81 sctx->buffer[partial++] = 0x80;
82 if (partial > bit_offset) {
83 memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial);
84 partial = 0;
85
86 block_fn(sctx, sctx->buffer, 1);
87 }
88
89 memset(sctx->buffer + partial, 0x0, bit_offset - partial);
90 *bits = cpu_to_be64(sctx->count << 3);
91 block_fn(sctx, sctx->buffer, 1);
92
93 return 0;
94 }
95
96 static inline int sha1_base_finish(struct shash_desc *desc, u8 *out)
97 {
98 struct sha1_state *sctx = shash_desc_ctx(desc);
99 __be32 *digest = (__be32 *)out;
100 int i;
101
102 for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++)
103 put_unaligned_be32(sctx->state[i], digest++);
104
105 memzero_explicit(sctx, sizeof(*sctx));
106 return 0;
107 }
108
109 #endif /* _CRYPTO_SHA1_BASE_H */
110
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