1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * sha256_base.h - core logic for SHA-256 implementations
5 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
8 #ifndef _CRYPTO_SHA256_BASE_H
9 #define _CRYPTO_SHA256_BASE_H
11 #include <crypto/internal/hash.h>
12 #include <crypto/sha.h>
13 #include <linux/crypto.h>
14 #include <linux/module.h>
16 #include <asm/unaligned.h>
18 typedef void (sha256_block_fn)(struct sha256_state *sst, u8 const *src,
21 static inline int sha224_base_init(struct shash_desc *desc)
23 struct sha256_state *sctx = shash_desc_ctx(desc);
29 static inline int sha256_base_init(struct shash_desc *desc)
31 struct sha256_state *sctx = shash_desc_ctx(desc);
37 static inline int sha256_base_do_update(struct shash_desc *desc,
40 sha256_block_fn *block_fn)
42 struct sha256_state *sctx = shash_desc_ctx(desc);
43 unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
47 if (unlikely((partial + len) >= SHA256_BLOCK_SIZE)) {
51 int p = SHA256_BLOCK_SIZE - partial;
53 memcpy(sctx->buf + partial, data, p);
57 block_fn(sctx, sctx->buf, 1);
60 blocks = len / SHA256_BLOCK_SIZE;
61 len %= SHA256_BLOCK_SIZE;
64 block_fn(sctx, data, blocks);
65 data += blocks * SHA256_BLOCK_SIZE;
70 memcpy(sctx->buf + partial, data, len);
75 static inline int sha256_base_do_finalize(struct shash_desc *desc,
76 sha256_block_fn *block_fn)
78 const int bit_offset = SHA256_BLOCK_SIZE - sizeof(__be64);
79 struct sha256_state *sctx = shash_desc_ctx(desc);
80 __be64 *bits = (__be64 *)(sctx->buf + bit_offset);
81 unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
83 sctx->buf[partial++] = 0x80;
84 if (partial > bit_offset) {
85 memset(sctx->buf + partial, 0x0, SHA256_BLOCK_SIZE - partial);
88 block_fn(sctx, sctx->buf, 1);
91 memset(sctx->buf + partial, 0x0, bit_offset - partial);
92 *bits = cpu_to_be64(sctx->count << 3);
93 block_fn(sctx, sctx->buf, 1);
98 static inline int sha256_base_finish(struct shash_desc *desc, u8 *out)
100 unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
101 struct sha256_state *sctx = shash_desc_ctx(desc);
102 __be32 *digest = (__be32 *)out;
105 for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be32))
106 put_unaligned_be32(sctx->state[i], digest++);
108 *sctx = (struct sha256_state){};
112 #endif /* _CRYPTO_SHA256_BASE_H */