kernel/arch/mips/cavium-octeon/crypto/octeon-sha1.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * SHA1 Secure Hash Algorithm.
   5  *
   6  * Adapted for OCTEON by Aaro Koskinen <aaro.koskinen@iki.fi>.
   7  *
   8  * Based on crypto/sha1_generic.c, which is:
   9  *
  10  * Copyright (c) Alan Smithee.
  11  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
  12  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
  13  *
  14  * This program is free software; you can redistribute it and/or modify it
  15  * under the terms of the GNU General Public License as published by the Free
  16  * Software Foundation; either version 2 of the License, or (at your option)
  17  * any later version.
  18  */
  19
  20 #include <linux/mm.h>
  21 #include <crypto/sha.h>
  22 #include <linux/init.h>
  23 #include <linux/types.h>
  24 #include <linux/module.h>
  25 #include <asm/byteorder.h>
  26 #include <asm/octeon/octeon.h>
  27 #include <crypto/internal/hash.h>
  28
  29 #include "octeon-crypto.h"
  30
  31 /*
  32  * We pass everything as 64-bit. OCTEON can handle misaligned data.
  33  */
  34
  35 static void octeon_sha1_store_hash(struct sha1_state *sctx)
  36 {
  37         u64 *hash = (u64 *)sctx->state;
  38         union {
  39                 u32 word[2];
  40                 u64 dword;
  41         } hash_tail = { { sctx->state[4], } };
  42
  43         write_octeon_64bit_hash_dword(hash[0], 0);
  44         write_octeon_64bit_hash_dword(hash[1], 1);
  45         write_octeon_64bit_hash_dword(hash_tail.dword, 2);
  46         memzero_explicit(&hash_tail.word[0], sizeof(hash_tail.word[0]));
  47 }
  48
  49 static void octeon_sha1_read_hash(struct sha1_state *sctx)
  50 {
  51         u64 *hash = (u64 *)sctx->state;
  52         union {
  53                 u32 word[2];
  54                 u64 dword;
  55         } hash_tail;
  56
  57         hash[0]         = read_octeon_64bit_hash_dword(0);
  58         hash[1]         = read_octeon_64bit_hash_dword(1);
  59         hash_tail.dword = read_octeon_64bit_hash_dword(2);
  60         sctx->state[4]  = hash_tail.word[0];
  61         memzero_explicit(&hash_tail.dword, sizeof(hash_tail.dword));
  62 }
  63
  64 static void octeon_sha1_transform(const void *_block)
  65 {
  66         const u64 *block = _block;
  67
  68         write_octeon_64bit_block_dword(block[0], 0);
  69         write_octeon_64bit_block_dword(block[1], 1);
  70         write_octeon_64bit_block_dword(block[2], 2);
  71         write_octeon_64bit_block_dword(block[3], 3);
  72         write_octeon_64bit_block_dword(block[4], 4);
  73         write_octeon_64bit_block_dword(block[5], 5);
  74         write_octeon_64bit_block_dword(block[6], 6);
  75         octeon_sha1_start(block[7]);
  76 }
  77
  78 static int octeon_sha1_init(struct shash_desc *desc)
  79 {
  80         struct sha1_state *sctx = shash_desc_ctx(desc);
  81
  82         sctx->state[0] = SHA1_H0;
  83         sctx->state[1] = SHA1_H1;
  84         sctx->state[2] = SHA1_H2;
  85         sctx->state[3] = SHA1_H3;
  86         sctx->state[4] = SHA1_H4;
  87         sctx->count = 0;
  88
  89         return 0;
  90 }
  91
  92 static void __octeon_sha1_update(struct sha1_state *sctx, const u8 *data,
  93                                  unsigned int len)
  94 {
  95         unsigned int partial;
  96         unsigned int done;
  97         const u8 *src;
  98
  99         partial = sctx->count % SHA1_BLOCK_SIZE;
 100         sctx->count += len;
 101         done = 0;
 102         src = data;
 103
 104         if ((partial + len) >= SHA1_BLOCK_SIZE) {
 105                 if (partial) {
 106                         done = -partial;
 107                         memcpy(sctx->buffer + partial, data,
 108                                done + SHA1_BLOCK_SIZE);
 109                         src = sctx->buffer;
 110                 }
 111
 112                 do {
 113                         octeon_sha1_transform(src);
 114                         done += SHA1_BLOCK_SIZE;
 115                         src = data + done;
 116                 } while (done + SHA1_BLOCK_SIZE <= len);
 117
 118                 partial = 0;
 119         }
 120         memcpy(sctx->buffer + partial, src, len - done);
 121 }
 122
 123 static int octeon_sha1_update(struct shash_desc *desc, const u8 *data,
 124                         unsigned int len)
 125 {
 126         struct sha1_state *sctx = shash_desc_ctx(desc);
 127         struct octeon_cop2_state state;
 128         unsigned long flags;
 129
 130         /*
 131          * Small updates never reach the crypto engine, so the generic sha1 is
 132          * faster because of the heavyweight octeon_crypto_enable() /
 133          * octeon_crypto_disable().
 134          */
 135         if ((sctx->count % SHA1_BLOCK_SIZE) + len < SHA1_BLOCK_SIZE)
 136                 return crypto_sha1_update(desc, data, len);
 137
 138         flags = octeon_crypto_enable(&state);
 139         octeon_sha1_store_hash(sctx);
 140
 141         __octeon_sha1_update(sctx, data, len);
 142
 143         octeon_sha1_read_hash(sctx);
 144         octeon_crypto_disable(&state, flags);
 145
 146         return 0;
 147 }
 148
 149 static int octeon_sha1_final(struct shash_desc *desc, u8 *out)
 150 {
 151         struct sha1_state *sctx = shash_desc_ctx(desc);
 152         static const u8 padding[64] = { 0x80, };
 153         struct octeon_cop2_state state;
 154         __be32 *dst = (__be32 *)out;
 155         unsigned int pad_len;
 156         unsigned long flags;
 157         unsigned int index;
 158         __be64 bits;
 159         int i;
 160
 161         /* Save number of bits. */
 162         bits = cpu_to_be64(sctx->count << 3);
 163
 164         /* Pad out to 56 mod 64. */
 165         index = sctx->count & 0x3f;
 166         pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
 167
 168         flags = octeon_crypto_enable(&state);
 169         octeon_sha1_store_hash(sctx);
 170
 171         __octeon_sha1_update(sctx, padding, pad_len);
 172
 173         /* Append length (before padding). */
 174         __octeon_sha1_update(sctx, (const u8 *)&bits, sizeof(bits));
 175
 176         octeon_sha1_read_hash(sctx);
 177         octeon_crypto_disable(&state, flags);
 178
 179         /* Store state in digest */
 180         for (i = 0; i < 5; i++)
 181                 dst[i] = cpu_to_be32(sctx->state[i]);
 182
 183         /* Zeroize sensitive information. */
 184         memset(sctx, 0, sizeof(*sctx));
 185
 186         return 0;
 187 }
 188
 189 static int octeon_sha1_export(struct shash_desc *desc, void *out)
 190 {
 191         struct sha1_state *sctx = shash_desc_ctx(desc);
 192
 193         memcpy(out, sctx, sizeof(*sctx));
 194         return 0;
 195 }
 196
 197 static int octeon_sha1_import(struct shash_desc *desc, const void *in)
 198 {
 199         struct sha1_state *sctx = shash_desc_ctx(desc);
 200
 201         memcpy(sctx, in, sizeof(*sctx));
 202         return 0;
 203 }
 204
 205 static struct shash_alg octeon_sha1_alg = {
 206         .digestsize     =       SHA1_DIGEST_SIZE,
 207         .init           =       octeon_sha1_init,
 208         .update         =       octeon_sha1_update,
 209         .final          =       octeon_sha1_final,
 210         .export         =       octeon_sha1_export,
 211         .import         =       octeon_sha1_import,
 212         .descsize       =       sizeof(struct sha1_state),
 213         .statesize      =       sizeof(struct sha1_state),
 214         .base           =       {
 215                 .cra_name       =       "sha1",
 216                 .cra_driver_name=       "octeon-sha1",
 217                 .cra_priority   =       OCTEON_CR_OPCODE_PRIORITY,
 218                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 219                 .cra_blocksize  =       SHA1_BLOCK_SIZE,
 220                 .cra_module     =       THIS_MODULE,
 221         }
 222 };
 223
 224 static int __init octeon_sha1_mod_init(void)
 225 {
 226         if (!octeon_has_crypto())
 227                 return -ENOTSUPP;
 228         return crypto_register_shash(&octeon_sha1_alg);
 229 }
 230
 231 static void __exit octeon_sha1_mod_fini(void)
 232 {
 233         crypto_unregister_shash(&octeon_sha1_alg);
 234 }
 235
 236 module_init(octeon_sha1_mod_init);
 237 module_exit(octeon_sha1_mod_fini);
 238
 239 MODULE_LICENSE("GPL");
 240 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm (OCTEON)");
 241 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");