xref: /openbmc/linux/include/crypto/sha512_base.h (revision 2cf1c348)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * sha512_base.h - core logic for SHA-512 implementations
4  *
5  * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
6  */
7 
8 #ifndef _CRYPTO_SHA512_BASE_H
9 #define _CRYPTO_SHA512_BASE_H
10 
11 #include <crypto/internal/hash.h>
12 #include <crypto/sha2.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 (sha512_block_fn)(struct sha512_state *sst, u8 const *src,
20 			       int blocks);
21 
22 static inline int sha384_base_init(struct shash_desc *desc)
23 {
24 	struct sha512_state *sctx = shash_desc_ctx(desc);
25 
26 	sctx->state[0] = SHA384_H0;
27 	sctx->state[1] = SHA384_H1;
28 	sctx->state[2] = SHA384_H2;
29 	sctx->state[3] = SHA384_H3;
30 	sctx->state[4] = SHA384_H4;
31 	sctx->state[5] = SHA384_H5;
32 	sctx->state[6] = SHA384_H6;
33 	sctx->state[7] = SHA384_H7;
34 	sctx->count[0] = sctx->count[1] = 0;
35 
36 	return 0;
37 }
38 
39 static inline int sha512_base_init(struct shash_desc *desc)
40 {
41 	struct sha512_state *sctx = shash_desc_ctx(desc);
42 
43 	sctx->state[0] = SHA512_H0;
44 	sctx->state[1] = SHA512_H1;
45 	sctx->state[2] = SHA512_H2;
46 	sctx->state[3] = SHA512_H3;
47 	sctx->state[4] = SHA512_H4;
48 	sctx->state[5] = SHA512_H5;
49 	sctx->state[6] = SHA512_H6;
50 	sctx->state[7] = SHA512_H7;
51 	sctx->count[0] = sctx->count[1] = 0;
52 
53 	return 0;
54 }
55 
56 static inline int sha512_base_do_update(struct shash_desc *desc,
57 					const u8 *data,
58 					unsigned int len,
59 					sha512_block_fn *block_fn)
60 {
61 	struct sha512_state *sctx = shash_desc_ctx(desc);
62 	unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
63 
64 	sctx->count[0] += len;
65 	if (sctx->count[0] < len)
66 		sctx->count[1]++;
67 
68 	if (unlikely((partial + len) >= SHA512_BLOCK_SIZE)) {
69 		int blocks;
70 
71 		if (partial) {
72 			int p = SHA512_BLOCK_SIZE - partial;
73 
74 			memcpy(sctx->buf + partial, data, p);
75 			data += p;
76 			len -= p;
77 
78 			block_fn(sctx, sctx->buf, 1);
79 		}
80 
81 		blocks = len / SHA512_BLOCK_SIZE;
82 		len %= SHA512_BLOCK_SIZE;
83 
84 		if (blocks) {
85 			block_fn(sctx, data, blocks);
86 			data += blocks * SHA512_BLOCK_SIZE;
87 		}
88 		partial = 0;
89 	}
90 	if (len)
91 		memcpy(sctx->buf + partial, data, len);
92 
93 	return 0;
94 }
95 
96 static inline int sha512_base_do_finalize(struct shash_desc *desc,
97 					  sha512_block_fn *block_fn)
98 {
99 	const int bit_offset = SHA512_BLOCK_SIZE - sizeof(__be64[2]);
100 	struct sha512_state *sctx = shash_desc_ctx(desc);
101 	__be64 *bits = (__be64 *)(sctx->buf + bit_offset);
102 	unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
103 
104 	sctx->buf[partial++] = 0x80;
105 	if (partial > bit_offset) {
106 		memset(sctx->buf + partial, 0x0, SHA512_BLOCK_SIZE - partial);
107 		partial = 0;
108 
109 		block_fn(sctx, sctx->buf, 1);
110 	}
111 
112 	memset(sctx->buf + partial, 0x0, bit_offset - partial);
113 	bits[0] = cpu_to_be64(sctx->count[1] << 3 | sctx->count[0] >> 61);
114 	bits[1] = cpu_to_be64(sctx->count[0] << 3);
115 	block_fn(sctx, sctx->buf, 1);
116 
117 	return 0;
118 }
119 
120 static inline int sha512_base_finish(struct shash_desc *desc, u8 *out)
121 {
122 	unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
123 	struct sha512_state *sctx = shash_desc_ctx(desc);
124 	__be64 *digest = (__be64 *)out;
125 	int i;
126 
127 	for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be64))
128 		put_unaligned_be64(sctx->state[i], digest++);
129 
130 	memzero_explicit(sctx, sizeof(*sctx));
131 	return 0;
132 }
133 
134 #endif /* _CRYPTO_SHA512_BASE_H */
135