arch/arm/crypto/sha1_glue.c

   1 /*
   2  * Cryptographic API.
   3  * Glue code for the SHA1 Secure Hash Algorithm assembler implementation
   4  *
   5  * This file is based on sha1_generic.c and sha1_ssse3_glue.c
   6  *
   7  * Copyright (c) Alan Smithee.
   8  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
   9  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
  10  * Copyright (c) Mathias Krause <minipli@googlemail.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 2 of the License, or (at your option)
  15  * any later version.
  16  *
  17  */
  18
  19 #include <crypto/internal/hash.h>
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/cryptohash.h>
  23 #include <linux/types.h>
  24 #include <crypto/sha.h>
  25 #include <asm/byteorder.h>
  26 #include <asm/crypto/sha1.h>
  27
  28
  29 asmlinkage void sha1_block_data_order(u32 *digest,
  30                 const unsigned char *data, unsigned int rounds);
  31
  32
  33 static int sha1_init(struct shash_desc *desc)
  34 {
  35         struct sha1_state *sctx = shash_desc_ctx(desc);
  36
  37         *sctx = (struct sha1_state){
  38                 .state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
  39         };
  40
  41         return 0;
  42 }
  43
  44
  45 static int __sha1_update(struct sha1_state *sctx, const u8 *data,
  46                          unsigned int len, unsigned int partial)
  47 {
  48         unsigned int done = 0;
  49
  50         sctx->count += len;
  51
  52         if (partial) {
  53                 done = SHA1_BLOCK_SIZE - partial;
  54                 memcpy(sctx->buffer + partial, data, done);
  55                 sha1_block_data_order(sctx->state, sctx->buffer, 1);
  56         }
  57
  58         if (len - done >= SHA1_BLOCK_SIZE) {
  59                 const unsigned int rounds = (len - done) / SHA1_BLOCK_SIZE;
  60                 sha1_block_data_order(sctx->state, data + done, rounds);
  61                 done += rounds * SHA1_BLOCK_SIZE;
  62         }
  63
  64         memcpy(sctx->buffer, data + done, len - done);
  65         return 0;
  66 }
  67
  68
  69 int sha1_update_arm(struct shash_desc *desc, const u8 *data,
  70                     unsigned int len)
  71 {
  72         struct sha1_state *sctx = shash_desc_ctx(desc);
  73         unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
  74         int res;
  75
  76         /* Handle the fast case right here */
  77         if (partial + len < SHA1_BLOCK_SIZE) {
  78                 sctx->count += len;
  79                 memcpy(sctx->buffer + partial, data, len);
  80                 return 0;
  81         }
  82         res = __sha1_update(sctx, data, len, partial);
  83         return res;
  84 }
  85 EXPORT_SYMBOL_GPL(sha1_update_arm);
  86
  87
  88 /* Add padding and return the message digest. */
  89 static int sha1_final(struct shash_desc *desc, u8 *out)
  90 {
  91         struct sha1_state *sctx = shash_desc_ctx(desc);
  92         unsigned int i, index, padlen;
  93         __be32 *dst = (__be32 *)out;
  94         __be64 bits;
  95         static const u8 padding[SHA1_BLOCK_SIZE] = { 0x80, };
  96
  97         bits = cpu_to_be64(sctx->count << 3);
  98
  99         /* Pad out to 56 mod 64 and append length */
 100         index = sctx->count % SHA1_BLOCK_SIZE;
 101         padlen = (index < 56) ? (56 - index) : ((SHA1_BLOCK_SIZE+56) - index);
 102         /* We need to fill a whole block for __sha1_update() */
 103         if (padlen <= 56) {
 104                 sctx->count += padlen;
 105                 memcpy(sctx->buffer + index, padding, padlen);
 106         } else {
 107                 __sha1_update(sctx, padding, padlen, index);
 108         }
 109         __sha1_update(sctx, (const u8 *)&bits, sizeof(bits), 56);
 110
 111         /* Store state in digest */
 112         for (i = 0; i < 5; i++)
 113                 dst[i] = cpu_to_be32(sctx->state[i]);
 114
 115         /* Wipe context */
 116         memset(sctx, 0, sizeof(*sctx));
 117         return 0;
 118 }
 119
 120
 121 static int sha1_export(struct shash_desc *desc, void *out)
 122 {
 123         struct sha1_state *sctx = shash_desc_ctx(desc);
 124         memcpy(out, sctx, sizeof(*sctx));
 125         return 0;
 126 }
 127
 128
 129 static int sha1_import(struct shash_desc *desc, const void *in)
 130 {
 131         struct sha1_state *sctx = shash_desc_ctx(desc);
 132         memcpy(sctx, in, sizeof(*sctx));
 133         return 0;
 134 }
 135
 136
 137 static struct shash_alg alg = {
 138         .digestsize     =       SHA1_DIGEST_SIZE,
 139         .init           =       sha1_init,
 140         .update         =       sha1_update_arm,
 141         .final          =       sha1_final,
 142         .export         =       sha1_export,
 143         .import         =       sha1_import,
 144         .descsize       =       sizeof(struct sha1_state),
 145         .statesize      =       sizeof(struct sha1_state),
 146         .base           =       {
 147                 .cra_name       =       "sha1",
 148                 .cra_driver_name=       "sha1-asm",
 149                 .cra_priority   =       150,
 150                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 151                 .cra_blocksize  =       SHA1_BLOCK_SIZE,
 152                 .cra_module     =       THIS_MODULE,
 153         }
 154 };
 155
 156
 157 static int __init sha1_mod_init(void)
 158 {
 159         return crypto_register_shash(&alg);
 160 }
 161
 162
 163 static void __exit sha1_mod_fini(void)
 164 {
 165         crypto_unregister_shash(&alg);
 166 }
 167
 168
 169 module_init(sha1_mod_init);
 170 module_exit(sha1_mod_fini);
 171
 172 MODULE_LICENSE("GPL");
 173 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm (ARM)");
 174 MODULE_ALIAS_CRYPTO("sha1");
 175 MODULE_AUTHOR("David McCullough <ucdevel@gmail.com>");