include/crypto/sha512_base.h

   1 /*
   2  * sha512_base.h - core logic for SHA-512 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 (sha512_block_fn)(struct sha512_state *sst, u8 const *src,
  19                                int blocks);
  20
  21 static inline int sha384_base_init(struct shash_desc *desc)
  22 {
  23         struct sha512_state *sctx = shash_desc_ctx(desc);
  24
  25         sctx->state[0] = SHA384_H0;
  26         sctx->state[1] = SHA384_H1;
  27         sctx->state[2] = SHA384_H2;
  28         sctx->state[3] = SHA384_H3;
  29         sctx->state[4] = SHA384_H4;
  30         sctx->state[5] = SHA384_H5;
  31         sctx->state[6] = SHA384_H6;
  32         sctx->state[7] = SHA384_H7;
  33         sctx->count[0] = sctx->count[1] = 0;
  34
  35         return 0;
  36 }
  37
  38 static inline int sha512_base_init(struct shash_desc *desc)
  39 {
  40         struct sha512_state *sctx = shash_desc_ctx(desc);
  41
  42         sctx->state[0] = SHA512_H0;
  43         sctx->state[1] = SHA512_H1;
  44         sctx->state[2] = SHA512_H2;
  45         sctx->state[3] = SHA512_H3;
  46         sctx->state[4] = SHA512_H4;
  47         sctx->state[5] = SHA512_H5;
  48         sctx->state[6] = SHA512_H6;
  49         sctx->state[7] = SHA512_H7;
  50         sctx->count[0] = sctx->count[1] = 0;
  51
  52         return 0;
  53 }
  54
  55 static inline int sha512_base_do_update(struct shash_desc *desc,
  56                                         const u8 *data,
  57                                         unsigned int len,
  58                                         sha512_block_fn *block_fn)
  59 {
  60         struct sha512_state *sctx = shash_desc_ctx(desc);
  61         unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
  62
  63         sctx->count[0] += len;
  64         if (sctx->count[0] < len)
  65                 sctx->count[1]++;
  66
  67         if (unlikely((partial + len) >= SHA512_BLOCK_SIZE)) {
  68                 int blocks;
  69
  70                 if (partial) {
  71                         int p = SHA512_BLOCK_SIZE - partial;
  72
  73                         memcpy(sctx->buf + partial, data, p);
  74                         data += p;
  75                         len -= p;
  76
  77                         block_fn(sctx, sctx->buf, 1);
  78                 }
  79
  80                 blocks = len / SHA512_BLOCK_SIZE;
  81                 len %= SHA512_BLOCK_SIZE;
  82
  83                 if (blocks) {
  84                         block_fn(sctx, data, blocks);
  85                         data += blocks * SHA512_BLOCK_SIZE;
  86                 }
  87                 partial = 0;
  88         }
  89         if (len)
  90                 memcpy(sctx->buf + partial, data, len);
  91
  92         return 0;
  93 }
  94
  95 static inline int sha512_base_do_finalize(struct shash_desc *desc,
  96                                           sha512_block_fn *block_fn)
  97 {
  98         const int bit_offset = SHA512_BLOCK_SIZE - sizeof(__be64[2]);
  99         struct sha512_state *sctx = shash_desc_ctx(desc);
 100         __be64 *bits = (__be64 *)(sctx->buf + bit_offset);
 101         unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
 102
 103         sctx->buf[partial++] = 0x80;
 104         if (partial > bit_offset) {
 105                 memset(sctx->buf + partial, 0x0, SHA512_BLOCK_SIZE - partial);
 106                 partial = 0;
 107
 108                 block_fn(sctx, sctx->buf, 1);
 109         }
 110
 111         memset(sctx->buf + partial, 0x0, bit_offset - partial);
 112         bits[0] = cpu_to_be64(sctx->count[1] << 3 | sctx->count[0] >> 61);
 113         bits[1] = cpu_to_be64(sctx->count[0] << 3);
 114         block_fn(sctx, sctx->buf, 1);
 115
 116         return 0;
 117 }
 118
 119 static inline int sha512_base_finish(struct shash_desc *desc, u8 *out)
 120 {
 121         unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
 122         struct sha512_state *sctx = shash_desc_ctx(desc);
 123         __be64 *digest = (__be64 *)out;
 124         int i;
 125
 126         for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be64))
 127                 put_unaligned_be64(sctx->state[i], digest++);
 128
 129         *sctx = (struct sha512_state){};
 130         return 0;
 131 }