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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * sha1_base.h - core logic for SHA-1 implementations4 *5 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>6 */7 8#ifndef _CRYPTO_SHA1_BASE_H9#define _CRYPTO_SHA1_BASE_H10 11#include <crypto/internal/hash.h>12#include <crypto/sha1.h>13#include <linux/crypto.h>14#include <linux/module.h>15#include <linux/string.h>16 17#include <linux/unaligned.h>18 19typedef void (sha1_block_fn)(struct sha1_state *sst, u8 const *src, int blocks);20 21static inline int sha1_base_init(struct shash_desc *desc)22{23	struct sha1_state *sctx = shash_desc_ctx(desc);24 25	sctx->state[0] = SHA1_H0;26	sctx->state[1] = SHA1_H1;27	sctx->state[2] = SHA1_H2;28	sctx->state[3] = SHA1_H3;29	sctx->state[4] = SHA1_H4;30	sctx->count = 0;31 32	return 0;33}34 35static inline int sha1_base_do_update(struct shash_desc *desc,36				      const u8 *data,37				      unsigned int len,38				      sha1_block_fn *block_fn)39{40	struct sha1_state *sctx = shash_desc_ctx(desc);41	unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;42 43	sctx->count += len;44 45	if (unlikely((partial + len) >= SHA1_BLOCK_SIZE)) {46		int blocks;47 48		if (partial) {49			int p = SHA1_BLOCK_SIZE - partial;50 51			memcpy(sctx->buffer + partial, data, p);52			data += p;53			len -= p;54 55			block_fn(sctx, sctx->buffer, 1);56		}57 58		blocks = len / SHA1_BLOCK_SIZE;59		len %= SHA1_BLOCK_SIZE;60 61		if (blocks) {62			block_fn(sctx, data, blocks);63			data += blocks * SHA1_BLOCK_SIZE;64		}65		partial = 0;66	}67	if (len)68		memcpy(sctx->buffer + partial, data, len);69 70	return 0;71}72 73static inline int sha1_base_do_finalize(struct shash_desc *desc,74					sha1_block_fn *block_fn)75{76	const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64);77	struct sha1_state *sctx = shash_desc_ctx(desc);78	__be64 *bits = (__be64 *)(sctx->buffer + bit_offset);79	unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;80 81	sctx->buffer[partial++] = 0x80;82	if (partial > bit_offset) {83		memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial);84		partial = 0;85 86		block_fn(sctx, sctx->buffer, 1);87	}88 89	memset(sctx->buffer + partial, 0x0, bit_offset - partial);90	*bits = cpu_to_be64(sctx->count << 3);91	block_fn(sctx, sctx->buffer, 1);92 93	return 0;94}95 96static inline int sha1_base_finish(struct shash_desc *desc, u8 *out)97{98	struct sha1_state *sctx = shash_desc_ctx(desc);99	__be32 *digest = (__be32 *)out;100	int i;101 102	for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++)103		put_unaligned_be32(sctx->state[i], digest++);104 105	memzero_explicit(sctx, sizeof(*sctx));106	return 0;107}108 109#endif /* _CRYPTO_SHA1_BASE_H */110