1 /* 2 * sha1_base.h - core logic for SHA-1 implementations 3 * 4 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 #include <crypto/internal/hash.h> 12 #include <crypto/sha.h> 13 #include <linux/crypto.h> 14 #include <linux/module.h> 15 16 #include <asm/unaligned.h> 17 18 typedef void (sha1_block_fn)(struct sha1_state *sst, u8 const *src, int blocks); 19 20 static inline int sha1_base_init(struct shash_desc *desc) 21 { 22 struct sha1_state *sctx = shash_desc_ctx(desc); 23 24 sctx->state[0] = SHA1_H0; 25 sctx->state[1] = SHA1_H1; 26 sctx->state[2] = SHA1_H2; 27 sctx->state[3] = SHA1_H3; 28 sctx->state[4] = SHA1_H4; 29 sctx->count = 0; 30 31 return 0; 32 } 33 34 static inline int sha1_base_do_update(struct shash_desc *desc, 35 const u8 *data, 36 unsigned int len, 37 sha1_block_fn *block_fn) 38 { 39 struct sha1_state *sctx = shash_desc_ctx(desc); 40 unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; 41 42 sctx->count += len; 43 44 if (unlikely((partial + len) >= SHA1_BLOCK_SIZE)) { 45 int blocks; 46 47 if (partial) { 48 int p = SHA1_BLOCK_SIZE - partial; 49 50 memcpy(sctx->buffer + partial, data, p); 51 data += p; 52 len -= p; 53 54 block_fn(sctx, sctx->buffer, 1); 55 } 56 57 blocks = len / SHA1_BLOCK_SIZE; 58 len %= SHA1_BLOCK_SIZE; 59 60 if (blocks) { 61 block_fn(sctx, data, blocks); 62 data += blocks * SHA1_BLOCK_SIZE; 63 } 64 partial = 0; 65 } 66 if (len) 67 memcpy(sctx->buffer + partial, data, len); 68 69 return 0; 70 } 71 72 static inline int sha1_base_do_finalize(struct shash_desc *desc, 73 sha1_block_fn *block_fn) 74 { 75 const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64); 76 struct sha1_state *sctx = shash_desc_ctx(desc); 77 __be64 *bits = (__be64 *)(sctx->buffer + bit_offset); 78 unsigned int partial = sctx->count % SHA1_BLOCK_SIZE; 79 80 sctx->buffer[partial++] = 0x80; 81 if (partial > bit_offset) { 82 memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial); 83 partial = 0; 84 85 block_fn(sctx, sctx->buffer, 1); 86 } 87 88 memset(sctx->buffer + partial, 0x0, bit_offset - partial); 89 *bits = cpu_to_be64(sctx->count << 3); 90 block_fn(sctx, sctx->buffer, 1); 91 92 return 0; 93 } 94 95 static inline int sha1_base_finish(struct shash_desc *desc, u8 *out) 96 { 97 struct sha1_state *sctx = shash_desc_ctx(desc); 98 __be32 *digest = (__be32 *)out; 99 int i; 100 101 for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++) 102 put_unaligned_be32(sctx->state[i], digest++); 103 104 *sctx = (struct sha1_state){}; 105 return 0; 106 } 107