include/crypto/sm3_base.h

   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 <[email protected]>
   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 */