arch/x86/crypto/sha512_ssse3_glue.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * Glue code for the SHA512 Secure Hash Algorithm assembler
   5  * implementation using supplemental SSE3 / AVX / AVX2 instructions.
   6  *
   7  * This file is based on sha512_generic.c
   8  *
   9  * Copyright (C) 2013 Intel Corporation
  10  * Author: Tim Chen <tim.c.chen@linux.intel.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  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  21  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  22  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24  * SOFTWARE.
  25  *
  26  */
  27
  28 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  29
  30 #include <crypto/internal/hash.h>
  31 #include <linux/init.h>
  32 #include <linux/module.h>
  33 #include <linux/mm.h>
  34 #include <linux/cryptohash.h>
  35 #include <linux/types.h>
  36 #include <crypto/sha.h>
  37 #include <asm/byteorder.h>
  38 #include <asm/i387.h>
  39 #include <asm/xcr.h>
  40 #include <asm/xsave.h>
  41
  42 #include <linux/string.h>
  43
  44 asmlinkage void sha512_transform_ssse3(const char *data, u64 *digest,
  45                                      u64 rounds);
  46 #ifdef CONFIG_AS_AVX
  47 asmlinkage void sha512_transform_avx(const char *data, u64 *digest,
  48                                      u64 rounds);
  49 #endif
  50 #ifdef CONFIG_AS_AVX2
  51 asmlinkage void sha512_transform_rorx(const char *data, u64 *digest,
  52                                      u64 rounds);
  53 #endif
  54
  55 static asmlinkage void (*sha512_transform_asm)(const char *, u64 *, u64);
  56
  57
  58 static int sha512_ssse3_init(struct shash_desc *desc)
  59 {
  60         struct sha512_state *sctx = shash_desc_ctx(desc);
  61
  62         sctx->state[0] = SHA512_H0;
  63         sctx->state[1] = SHA512_H1;
  64         sctx->state[2] = SHA512_H2;
  65         sctx->state[3] = SHA512_H3;
  66         sctx->state[4] = SHA512_H4;
  67         sctx->state[5] = SHA512_H5;
  68         sctx->state[6] = SHA512_H6;
  69         sctx->state[7] = SHA512_H7;
  70         sctx->count[0] = sctx->count[1] = 0;
  71
  72         return 0;
  73 }
  74
  75 static int __sha512_ssse3_update(struct shash_desc *desc, const u8 *data,
  76                                unsigned int len, unsigned int partial)
  77 {
  78         struct sha512_state *sctx = shash_desc_ctx(desc);
  79         unsigned int done = 0;
  80
  81         sctx->count[0] += len;
  82         if (sctx->count[0] < len)
  83                 sctx->count[1]++;
  84
  85         if (partial) {
  86                 done = SHA512_BLOCK_SIZE - partial;
  87                 memcpy(sctx->buf + partial, data, done);
  88                 sha512_transform_asm(sctx->buf, sctx->state, 1);
  89         }
  90
  91         if (len - done >= SHA512_BLOCK_SIZE) {
  92                 const unsigned int rounds = (len - done) / SHA512_BLOCK_SIZE;
  93
  94                 sha512_transform_asm(data + done, sctx->state, (u64) rounds);
  95
  96                 done += rounds * SHA512_BLOCK_SIZE;
  97         }
  98
  99         memcpy(sctx->buf, data + done, len - done);
 100
 101         return 0;
 102 }
 103
 104 static int sha512_ssse3_update(struct shash_desc *desc, const u8 *data,
 105                              unsigned int len)
 106 {
 107         struct sha512_state *sctx = shash_desc_ctx(desc);
 108         unsigned int partial = sctx->count[0] % SHA512_BLOCK_SIZE;
 109         int res;
 110
 111         /* Handle the fast case right here */
 112         if (partial + len < SHA512_BLOCK_SIZE) {
 113                 sctx->count[0] += len;
 114                 if (sctx->count[0] < len)
 115                         sctx->count[1]++;
 116                 memcpy(sctx->buf + partial, data, len);
 117
 118                 return 0;
 119         }
 120
 121         if (!irq_fpu_usable()) {
 122                 res = crypto_sha512_update(desc, data, len);
 123         } else {
 124                 kernel_fpu_begin();
 125                 res = __sha512_ssse3_update(desc, data, len, partial);
 126                 kernel_fpu_end();
 127         }
 128
 129         return res;
 130 }
 131
 132
 133 /* Add padding and return the message digest. */
 134 static int sha512_ssse3_final(struct shash_desc *desc, u8 *out)
 135 {
 136         struct sha512_state *sctx = shash_desc_ctx(desc);
 137         unsigned int i, index, padlen;
 138         __be64 *dst = (__be64 *)out;
 139         __be64 bits[2];
 140         static const u8 padding[SHA512_BLOCK_SIZE] = { 0x80, };
 141
 142         /* save number of bits */
 143         bits[1] = cpu_to_be64(sctx->count[0] << 3);
 144         bits[0] = cpu_to_be64(sctx->count[1] << 3) | sctx->count[0] >> 61;
 145
 146         /* Pad out to 112 mod 128 and append length */
 147         index = sctx->count[0] & 0x7f;
 148         padlen = (index < 112) ? (112 - index) : ((128+112) - index);
 149
 150         if (!irq_fpu_usable()) {
 151                 crypto_sha512_update(desc, padding, padlen);
 152                 crypto_sha512_update(desc, (const u8 *)&bits, sizeof(bits));
 153         } else {
 154                 kernel_fpu_begin();
 155                 /* We need to fill a whole block for __sha512_ssse3_update() */
 156                 if (padlen <= 112) {
 157                         sctx->count[0] += padlen;
 158                         if (sctx->count[0] < padlen)
 159                                 sctx->count[1]++;
 160                         memcpy(sctx->buf + index, padding, padlen);
 161                 } else {
 162                         __sha512_ssse3_update(desc, padding, padlen, index);
 163                 }
 164                 __sha512_ssse3_update(desc, (const u8 *)&bits,
 165                                         sizeof(bits), 112);
 166                 kernel_fpu_end();
 167         }
 168
 169         /* Store state in digest */
 170         for (i = 0; i < 8; i++)
 171                 dst[i] = cpu_to_be64(sctx->state[i]);
 172
 173         /* Wipe context */
 174         memset(sctx, 0, sizeof(*sctx));
 175
 176         return 0;
 177 }
 178
 179 static int sha512_ssse3_export(struct shash_desc *desc, void *out)
 180 {
 181         struct sha512_state *sctx = shash_desc_ctx(desc);
 182
 183         memcpy(out, sctx, sizeof(*sctx));
 184
 185         return 0;
 186 }
 187
 188 static int sha512_ssse3_import(struct shash_desc *desc, const void *in)
 189 {
 190         struct sha512_state *sctx = shash_desc_ctx(desc);
 191
 192         memcpy(sctx, in, sizeof(*sctx));
 193
 194         return 0;
 195 }
 196
 197 static struct shash_alg alg = {
 198         .digestsize     =       SHA512_DIGEST_SIZE,
 199         .init           =       sha512_ssse3_init,
 200         .update         =       sha512_ssse3_update,
 201         .final          =       sha512_ssse3_final,
 202         .export         =       sha512_ssse3_export,
 203         .import         =       sha512_ssse3_import,
 204         .descsize       =       sizeof(struct sha512_state),
 205         .statesize      =       sizeof(struct sha512_state),
 206         .base           =       {
 207                 .cra_name       =       "sha512",
 208                 .cra_driver_name =      "sha512-ssse3",
 209                 .cra_priority   =       150,
 210                 .cra_flags      =       CRYPTO_ALG_TYPE_SHASH,
 211                 .cra_blocksize  =       SHA512_BLOCK_SIZE,
 212                 .cra_module     =       THIS_MODULE,
 213         }
 214 };
 215
 216 #ifdef CONFIG_AS_AVX
 217 static bool __init avx_usable(void)
 218 {
 219         u64 xcr0;
 220
 221         if (!cpu_has_avx || !cpu_has_osxsave)
 222                 return false;
 223
 224         xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
 225         if ((xcr0 & (XSTATE_SSE | XSTATE_YMM)) != (XSTATE_SSE | XSTATE_YMM)) {
 226                 pr_info("AVX detected but unusable.\n");
 227
 228                 return false;
 229         }
 230
 231         return true;
 232 }
 233 #endif
 234
 235 static int __init sha512_ssse3_mod_init(void)
 236 {
 237         /* test for SSE3 first */
 238         if (cpu_has_ssse3)
 239                 sha512_transform_asm = sha512_transform_ssse3;
 240
 241 #ifdef CONFIG_AS_AVX
 242         /* allow AVX to override SSSE3, it's a little faster */
 243         if (avx_usable()) {
 244 #ifdef CONFIG_AS_AVX2
 245                 if (boot_cpu_has(X86_FEATURE_AVX2))
 246                         sha512_transform_asm = sha512_transform_rorx;
 247                 else
 248 #endif
 249                         sha512_transform_asm = sha512_transform_avx;
 250         }
 251 #endif
 252
 253         if (sha512_transform_asm) {
 254 #ifdef CONFIG_AS_AVX
 255                 if (sha512_transform_asm == sha512_transform_avx)
 256                         pr_info("Using AVX optimized SHA-512 implementation\n");
 257 #ifdef CONFIG_AS_AVX2
 258                 else if (sha512_transform_asm == sha512_transform_rorx)
 259                         pr_info("Using AVX2 optimized SHA-512 implementation\n");
 260 #endif
 261                 else
 262 #endif
 263                         pr_info("Using SSSE3 optimized SHA-512 implementation\n");
 264                 return crypto_register_shash(&alg);
 265         }
 266         pr_info("Neither AVX nor SSSE3 is available/usable.\n");
 267
 268         return -ENODEV;
 269 }
 270
 271 static void __exit sha512_ssse3_mod_fini(void)
 272 {
 273         crypto_unregister_shash(&alg);
 274 }
 275
 276 module_init(sha512_ssse3_mod_init);
 277 module_exit(sha512_ssse3_mod_fini);
 278
 279 MODULE_LICENSE("GPL");
 280 MODULE_DESCRIPTION("SHA512 Secure Hash Algorithm, Supplemental SSE3 accelerated");
 281
 282 MODULE_ALIAS("sha512");