xref: /openbmc/linux/include/crypto/sm3_base.h (revision fb574682)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * sm3_base.h - core logic for SM3 implementations
4  *
5  * Copyright (C) 2017 ARM Limited or its affiliates.
6  * Written by Gilad Ben-Yossef <gilad@benyossef.com>
7  */
8 
9 #ifndef _CRYPTO_SM3_BASE_H
10 #define _CRYPTO_SM3_BASE_H
11 
12 #include <crypto/internal/hash.h>
13 #include <crypto/sm3.h>
14 #include <linux/crypto.h>
15 #include <linux/module.h>
16 #include <asm/unaligned.h>
17 
18 typedef void (sm3_block_fn)(struct sm3_state *sst, u8 const *src, int blocks);
19 
20 static inline int sm3_base_init(struct shash_desc *desc)
21 {
22 	struct sm3_state *sctx = shash_desc_ctx(desc);
23 
24 	sctx->state[0] = SM3_IVA;
25 	sctx->state[1] = SM3_IVB;
26 	sctx->state[2] = SM3_IVC;
27 	sctx->state[3] = SM3_IVD;
28 	sctx->state[4] = SM3_IVE;
29 	sctx->state[5] = SM3_IVF;
30 	sctx->state[6] = SM3_IVG;
31 	sctx->state[7] = SM3_IVH;
32 	sctx->count = 0;
33 
34 	return 0;
35 }
36 
37 static inline int sm3_base_do_update(struct shash_desc *desc,
38 				      const u8 *data,
39 				      unsigned int len,
40 				      sm3_block_fn *block_fn)
41 {
42 	struct sm3_state *sctx = shash_desc_ctx(desc);
43 	unsigned int partial = sctx->count % SM3_BLOCK_SIZE;
44 
45 	sctx->count += len;
46 
47 	if (unlikely((partial + len) >= SM3_BLOCK_SIZE)) {
48 		int blocks;
49 
50 		if (partial) {
51 			int p = SM3_BLOCK_SIZE - partial;
52 
53 			memcpy(sctx->buffer + partial, data, p);
54 			data += p;
55 			len -= p;
56 
57 			block_fn(sctx, sctx->buffer, 1);
58 		}
59 
60 		blocks = len / SM3_BLOCK_SIZE;
61 		len %= SM3_BLOCK_SIZE;
62 
63 		if (blocks) {
64 			block_fn(sctx, data, blocks);
65 			data += blocks * SM3_BLOCK_SIZE;
66 		}
67 		partial = 0;
68 	}
69 	if (len)
70 		memcpy(sctx->buffer + partial, data, len);
71 
72 	return 0;
73 }
74 
75 static inline int sm3_base_do_finalize(struct shash_desc *desc,
76 					sm3_block_fn *block_fn)
77 {
78 	const int bit_offset = SM3_BLOCK_SIZE - sizeof(__be64);
79 	struct sm3_state *sctx = shash_desc_ctx(desc);
80 	__be64 *bits = (__be64 *)(sctx->buffer + bit_offset);
81 	unsigned int partial = sctx->count % SM3_BLOCK_SIZE;
82 
83 	sctx->buffer[partial++] = 0x80;
84 	if (partial > bit_offset) {
85 		memset(sctx->buffer + partial, 0x0, SM3_BLOCK_SIZE - partial);
86 		partial = 0;
87 
88 		block_fn(sctx, sctx->buffer, 1);
89 	}
90 
91 	memset(sctx->buffer + partial, 0x0, bit_offset - partial);
92 	*bits = cpu_to_be64(sctx->count << 3);
93 	block_fn(sctx, sctx->buffer, 1);
94 
95 	return 0;
96 }
97 
98 static inline int sm3_base_finish(struct shash_desc *desc, u8 *out)
99 {
100 	struct sm3_state *sctx = shash_desc_ctx(desc);
101 	__be32 *digest = (__be32 *)out;
102 	int i;
103 
104 	for (i = 0; i < SM3_DIGEST_SIZE / sizeof(__be32); i++)
105 		put_unaligned_be32(sctx->state[i], digest++);
106 
107 	*sctx = (struct sm3_state){};
108 	return 0;
109 }
110 
111 #endif /* _CRYPTO_SM3_BASE_H */
112