xref: /openbmc/linux/include/crypto/sha512_base.h (revision ccd51b9f)
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 #include <crypto/internal/hash.h>
9 #include <crypto/sha.h>
10 #include <linux/crypto.h>
11 #include <linux/module.h>
12 
13 #include <asm/unaligned.h>
14 
15 typedef void (sha512_block_fn)(struct sha512_state *sst, u8 const *src,
16 			       int blocks);
17 
18 static inline int sha384_base_init(struct shash_desc *desc)
19 {
20 	struct sha512_state *sctx = shash_desc_ctx(desc);
21 
22 	sctx->state[0] = SHA384_H0;
23 	sctx->state[1] = SHA384_H1;
24 	sctx->state[2] = SHA384_H2;
25 	sctx->state[3] = SHA384_H3;
26 	sctx->state[4] = SHA384_H4;
27 	sctx->state[5] = SHA384_H5;
28 	sctx->state[6] = SHA384_H6;
29 	sctx->state[7] = SHA384_H7;
30 	sctx->count[0] = sctx->count[1] = 0;
31 
32 	return 0;
33 }
34 
35 static inline int sha512_base_init(struct shash_desc *desc)
36 {
37 	struct sha512_state *sctx = shash_desc_ctx(desc);
38 
39 	sctx->state[0] = SHA512_H0;
40 	sctx->state[1] = SHA512_H1;
41 	sctx->state[2] = SHA512_H2;
42 	sctx->state[3] = SHA512_H3;
43 	sctx->state[4] = SHA512_H4;
44 	sctx->state[5] = SHA512_H5;
45 	sctx->state[6] = SHA512_H6;
46 	sctx->state[7] = SHA512_H7;
47 	sctx->count[0] = sctx->count[1] = 0;
48 
49 	return 0;
50 }
51 
52 static inline int sha512_base_do_update(struct shash_desc *desc,
53 					const u8 *data,
54 					unsigned int len,
55 					sha512_block_fn *block_fn)
56 {
57 	struct sha512_state *sctx = shash_desc_ctx(desc);
58 	unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
59 
60 	sctx->count[0] += len;
61 	if (sctx->count[0] < len)
62 		sctx->count[1]++;
63 
64 	if (unlikely((partial + len) >= SHA512_BLOCK_SIZE)) {
65 		int blocks;
66 
67 		if (partial) {
68 			int p = SHA512_BLOCK_SIZE - partial;
69 
70 			memcpy(sctx->buf + partial, data, p);
71 			data += p;
72 			len -= p;
73 
74 			block_fn(sctx, sctx->buf, 1);
75 		}
76 
77 		blocks = len / SHA512_BLOCK_SIZE;
78 		len %= SHA512_BLOCK_SIZE;
79 
80 		if (blocks) {
81 			block_fn(sctx, data, blocks);
82 			data += blocks * SHA512_BLOCK_SIZE;
83 		}
84 		partial = 0;
85 	}
86 	if (len)
87 		memcpy(sctx->buf + partial, data, len);
88 
89 	return 0;
90 }
91 
92 static inline int sha512_base_do_finalize(struct shash_desc *desc,
93 					  sha512_block_fn *block_fn)
94 {
95 	const int bit_offset = SHA512_BLOCK_SIZE - sizeof(__be64[2]);
96 	struct sha512_state *sctx = shash_desc_ctx(desc);
97 	__be64 *bits = (__be64 *)(sctx->buf + bit_offset);
98 	unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
99 
100 	sctx->buf[partial++] = 0x80;
101 	if (partial > bit_offset) {
102 		memset(sctx->buf + partial, 0x0, SHA512_BLOCK_SIZE - partial);
103 		partial = 0;
104 
105 		block_fn(sctx, sctx->buf, 1);
106 	}
107 
108 	memset(sctx->buf + partial, 0x0, bit_offset - partial);
109 	bits[0] = cpu_to_be64(sctx->count[1] << 3 | sctx->count[0] >> 61);
110 	bits[1] = cpu_to_be64(sctx->count[0] << 3);
111 	block_fn(sctx, sctx->buf, 1);
112 
113 	return 0;
114 }
115 
116 static inline int sha512_base_finish(struct shash_desc *desc, u8 *out)
117 {
118 	unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
119 	struct sha512_state *sctx = shash_desc_ctx(desc);
120 	__be64 *digest = (__be64 *)out;
121 	int i;
122 
123 	for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be64))
124 		put_unaligned_be64(sctx->state[i], digest++);
125 
126 	*sctx = (struct sha512_state){};
127 	return 0;
128 }
129