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
  27 struct SHA1_CTX {
  28         uint32_t h0,h1,h2,h3,h4;
  29         u64 count;
  30         u8 data[SHA1_BLOCK_SIZE];
  31 };
  32
  33 asmlinkage void sha1_block_data_order(struct SHA1_CTX *digest,
  34                 const unsigned char *data, unsigned int rounds);
  35
  36
  37 static int sha1_init(struct shash_desc *desc)
  38 {
  39         struct SHA1_CTX *sctx = shash_desc_ctx(desc);
  40         memset(sctx, 0, sizeof(*sctx));
  41         sctx->h0 = SHA1_H0;
  42         sctx->h1 = SHA1_H1;
  43         sctx->h2 = SHA1_H2;
  44         sctx->h3 = SHA1_H3;
  45         sctx->h4 = SHA1_H4;
  46         return 0;
  47 }
  48
  49
  50 static int __sha1_update(struct SHA1_CTX *sctx, const u8 *data,
  51                                unsigned int len, unsigned int partial)
  52 {
  53         unsigned int done = 0;
  54
  55         sctx->count += len;
  56
  57         if (partial) {
  58                 done = SHA1_BLOCK_SIZE - partial;
  59                 memcpy(sctx->data + partial, data, done);
  60                 sha1_block_data_order(sctx, sctx->data, 1);
  61         }
  62
  63         if (len - done >= SHA1_BLOCK_SIZE) {
  64                 const unsigned int rounds = (len - done) / SHA1_BLOCK_SIZE;
  65                 sha1_block_data_order(sctx, data + done, rounds);
  66                 done += rounds * SHA1_BLOCK_SIZE;
  67         }
  68
  69         memcpy(sctx->data, data + done, len - done);
  70         return 0;
  71 }
  72
  73
  74 static int sha1_update(struct shash_desc *desc, const u8 *data,
  75                              unsigned int len)
  76 {
  77         struct SHA1_CTX *sctx = shash_desc_ctx(desc);
  78         unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
  79         int res;
  80
  81         /* Handle the fast case right here */
  82         if (partial + len < SHA1_BLOCK_SIZE) {
  83                 sctx->count += len;
  84                 memcpy(sctx->data + partial, data, len);
  85                 return 0;
  86         }
  87         res = __sha1_update(sctx, data, len, partial);
  88         return res;
  89 }
  90
  91
  92 /* Add padding and return the message digest. */
  93 static int sha1_final(struct shash_desc *desc, u8 *out)
  94 {
  95         struct SHA1_CTX *sctx = shash_desc_ctx(desc);
  96         unsigned int i, index, padlen;
  97         __be32 *dst = (__be32 *)out;
  98         __be64 bits;
  99         static const u8 padding[SHA1_BLOCK_SIZE] = { 0x80, };
 100
 101         bits = cpu_to_be64(sctx->count << 3);
 102
 103         /* Pad out to 56 mod 64 and append length */
 104         index = sctx->count % SHA1_BLOCK_SIZE;
 105         padlen = (index < 56) ? (56 - index) : ((SHA1_BLOCK_SIZE+56) - index);
 106         /* We need to fill a whole block for __sha1_update() */
 107         if (padlen <= 56) {
 108                 sctx->count += padlen;
 109                 memcpy(sctx->data + index, padding, padlen);
 110         } else {
 111                 __sha1_update(sctx, padding, padlen, index);
 112         }
 113         __sha1_update(sctx, (const u8 *)&bits, sizeof(bits), 56);
 114
 115         /* Store state in digest */
 116         for (i = 0; i < 5; i++)
 117                 dst[i] = cpu_to_be32(((u32 *)sctx)[i]);
 118
 119         /* Wipe context */
 120         memset(sctx, 0, sizeof(*sctx));
 121         return 0;
 122 }
 123
 124
 125 static int sha1_export(struct shash_desc *desc, void *out)
 126 {
 127         struct SHA1_CTX *sctx = shash_desc_ctx(desc);
 128         memcpy(out, sctx, sizeof(*sctx));
 129         return 0;
 130 }
 131
 132
 133 static int sha1_import(struct shash_desc *desc, const void *in)
 134 {
 135         struct SHA1_CTX *sctx = shash_desc_ctx(desc);
 136         memcpy(sctx, in, sizeof(*sctx));
 137         return 0;
 138 }
 139
 140
 141 static struct shash_alg alg = {
 142         .digestsize     =       SHA1_DIGEST_SIZE,
 143         .init           =       sha1_init,
 144         .update         =       sha1_update,
 145         .final          =       sha1_final,
 146         .export         =       sha1_export,
 147         .import         =       sha1_import,
 148         .descsize       =       sizeof(struct SHA1_CTX),
 149         .statesize      =       sizeof(struct SHA1_CTX),
 150         .base           =       {
 151                 .cra_name       =       "sha1",
 152                 .cra_driver_name=       "sha1-asm",
 153                 .cra_priority   =       150,
 154                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 155                 .cra_blocksize  =       SHA1_BLOCK_SIZE,
 156                 .cra_module     =       THIS_MODULE,
 157         }
 158 };
 159
 160
 161 static int __init sha1_mod_init(void)
 162 {
 163         return crypto_register_shash(&alg);
 164 }
 165
 166
 167 static void __exit sha1_mod_fini(void)
 168 {
 169         crypto_unregister_shash(&alg);
 170 }
 171
 172
 173 module_init(sha1_mod_init);
 174 module_exit(sha1_mod_fini);
 175
 176 MODULE_LICENSE("GPL");
 177 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm (ARM)");
 178 MODULE_ALIAS("sha1");
 179 MODULE_AUTHOR("David McCullough <ucdevel@gmail.com>");