1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * sha256_base.h - core logic for SHA-256 implementations |
4 | * |
5 | * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org> |
6 | */ |
7 | |
8 | #ifndef _CRYPTO_SHA256_BASE_H |
9 | #define _CRYPTO_SHA256_BASE_H |
10 | |
11 | #include <asm/byteorder.h> |
12 | #include <asm/unaligned.h> |
13 | #include <crypto/internal/hash.h> |
14 | #include <crypto/sha2.h> |
15 | #include <linux/string.h> |
16 | #include <linux/types.h> |
17 | |
18 | typedef void (sha256_block_fn)(struct sha256_state *sst, u8 const *src, |
19 | int blocks); |
20 | |
21 | static inline int sha224_base_init(struct shash_desc *desc) |
22 | { |
23 | struct sha256_state *sctx = shash_desc_ctx(desc); |
24 | |
25 | sha224_init(sctx); |
26 | return 0; |
27 | } |
28 | |
29 | static inline int sha256_base_init(struct shash_desc *desc) |
30 | { |
31 | struct sha256_state *sctx = shash_desc_ctx(desc); |
32 | |
33 | sha256_init(sctx); |
34 | return 0; |
35 | } |
36 | |
37 | static inline int lib_sha256_base_do_update(struct sha256_state *sctx, |
38 | const u8 *data, |
39 | unsigned int len, |
40 | sha256_block_fn *block_fn) |
41 | { |
42 | unsigned int partial = sctx->count % SHA256_BLOCK_SIZE; |
43 | |
44 | sctx->count += len; |
45 | |
46 | if (unlikely((partial + len) >= SHA256_BLOCK_SIZE)) { |
47 | int blocks; |
48 | |
49 | if (partial) { |
50 | int p = SHA256_BLOCK_SIZE - partial; |
51 | |
52 | memcpy(sctx->buf + partial, data, p); |
53 | data += p; |
54 | len -= p; |
55 | |
56 | block_fn(sctx, sctx->buf, 1); |
57 | } |
58 | |
59 | blocks = len / SHA256_BLOCK_SIZE; |
60 | len %= SHA256_BLOCK_SIZE; |
61 | |
62 | if (blocks) { |
63 | block_fn(sctx, data, blocks); |
64 | data += blocks * SHA256_BLOCK_SIZE; |
65 | } |
66 | partial = 0; |
67 | } |
68 | if (len) |
69 | memcpy(sctx->buf + partial, data, len); |
70 | |
71 | return 0; |
72 | } |
73 | |
74 | static inline int sha256_base_do_update(struct shash_desc *desc, |
75 | const u8 *data, |
76 | unsigned int len, |
77 | sha256_block_fn *block_fn) |
78 | { |
79 | struct sha256_state *sctx = shash_desc_ctx(desc); |
80 | |
81 | return lib_sha256_base_do_update(sctx, data, len, block_fn); |
82 | } |
83 | |
84 | static inline int lib_sha256_base_do_finalize(struct sha256_state *sctx, |
85 | sha256_block_fn *block_fn) |
86 | { |
87 | const int bit_offset = SHA256_BLOCK_SIZE - sizeof(__be64); |
88 | __be64 *bits = (__be64 *)(sctx->buf + bit_offset); |
89 | unsigned int partial = sctx->count % SHA256_BLOCK_SIZE; |
90 | |
91 | sctx->buf[partial++] = 0x80; |
92 | if (partial > bit_offset) { |
93 | memset(sctx->buf + partial, 0x0, SHA256_BLOCK_SIZE - partial); |
94 | partial = 0; |
95 | |
96 | block_fn(sctx, sctx->buf, 1); |
97 | } |
98 | |
99 | memset(sctx->buf + partial, 0x0, bit_offset - partial); |
100 | *bits = cpu_to_be64(sctx->count << 3); |
101 | block_fn(sctx, sctx->buf, 1); |
102 | |
103 | return 0; |
104 | } |
105 | |
106 | static inline int sha256_base_do_finalize(struct shash_desc *desc, |
107 | sha256_block_fn *block_fn) |
108 | { |
109 | struct sha256_state *sctx = shash_desc_ctx(desc); |
110 | |
111 | return lib_sha256_base_do_finalize(sctx, block_fn); |
112 | } |
113 | |
114 | static inline int lib_sha256_base_finish(struct sha256_state *sctx, u8 *out, |
115 | unsigned int digest_size) |
116 | { |
117 | __be32 *digest = (__be32 *)out; |
118 | int i; |
119 | |
120 | for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be32)) |
121 | put_unaligned_be32(val: sctx->state[i], p: digest++); |
122 | |
123 | memzero_explicit(s: sctx, count: sizeof(*sctx)); |
124 | return 0; |
125 | } |
126 | |
127 | static inline int sha256_base_finish(struct shash_desc *desc, u8 *out) |
128 | { |
129 | unsigned int digest_size = crypto_shash_digestsize(tfm: desc->tfm); |
130 | struct sha256_state *sctx = shash_desc_ctx(desc); |
131 | |
132 | return lib_sha256_base_finish(sctx, out, digest_size); |
133 | } |
134 | |
135 | #endif /* _CRYPTO_SHA256_BASE_H */ |
136 | |