Merge branch 'samsung/exynos5' into next/soc2
[linux-2.6.git] / arch / x86 / crypto / ghash-clmulni-intel_glue.c
1 /*
2  * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
3  * instructions. This file contains glue code.
4  *
5  * Copyright (c) 2009 Intel Corp.
6  *   Author: Huang Ying <ying.huang@intel.com>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License version 2 as published
10  * by the Free Software Foundation.
11  */
12
13 #include <linux/err.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/crypto.h>
18 #include <crypto/algapi.h>
19 #include <crypto/cryptd.h>
20 #include <crypto/gf128mul.h>
21 #include <crypto/internal/hash.h>
22 #include <asm/i387.h>
23 #include <asm/cpu_device_id.h>
24
25 #define GHASH_BLOCK_SIZE        16
26 #define GHASH_DIGEST_SIZE       16
27
28 void clmul_ghash_mul(char *dst, const be128 *shash);
29
30 void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
31                         const be128 *shash);
32
33 void clmul_ghash_setkey(be128 *shash, const u8 *key);
34
35 struct ghash_async_ctx {
36         struct cryptd_ahash *cryptd_tfm;
37 };
38
39 struct ghash_ctx {
40         be128 shash;
41 };
42
43 struct ghash_desc_ctx {
44         u8 buffer[GHASH_BLOCK_SIZE];
45         u32 bytes;
46 };
47
48 static int ghash_init(struct shash_desc *desc)
49 {
50         struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
51
52         memset(dctx, 0, sizeof(*dctx));
53
54         return 0;
55 }
56
57 static int ghash_setkey(struct crypto_shash *tfm,
58                         const u8 *key, unsigned int keylen)
59 {
60         struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
61
62         if (keylen != GHASH_BLOCK_SIZE) {
63                 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
64                 return -EINVAL;
65         }
66
67         clmul_ghash_setkey(&ctx->shash, key);
68
69         return 0;
70 }
71
72 static int ghash_update(struct shash_desc *desc,
73                          const u8 *src, unsigned int srclen)
74 {
75         struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
76         struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
77         u8 *dst = dctx->buffer;
78
79         kernel_fpu_begin();
80         if (dctx->bytes) {
81                 int n = min(srclen, dctx->bytes);
82                 u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
83
84                 dctx->bytes -= n;
85                 srclen -= n;
86
87                 while (n--)
88                         *pos++ ^= *src++;
89
90                 if (!dctx->bytes)
91                         clmul_ghash_mul(dst, &ctx->shash);
92         }
93
94         clmul_ghash_update(dst, src, srclen, &ctx->shash);
95         kernel_fpu_end();
96
97         if (srclen & 0xf) {
98                 src += srclen - (srclen & 0xf);
99                 srclen &= 0xf;
100                 dctx->bytes = GHASH_BLOCK_SIZE - srclen;
101                 while (srclen--)
102                         *dst++ ^= *src++;
103         }
104
105         return 0;
106 }
107
108 static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
109 {
110         u8 *dst = dctx->buffer;
111
112         if (dctx->bytes) {
113                 u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
114
115                 while (dctx->bytes--)
116                         *tmp++ ^= 0;
117
118                 kernel_fpu_begin();
119                 clmul_ghash_mul(dst, &ctx->shash);
120                 kernel_fpu_end();
121         }
122
123         dctx->bytes = 0;
124 }
125
126 static int ghash_final(struct shash_desc *desc, u8 *dst)
127 {
128         struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
129         struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
130         u8 *buf = dctx->buffer;
131
132         ghash_flush(ctx, dctx);
133         memcpy(dst, buf, GHASH_BLOCK_SIZE);
134
135         return 0;
136 }
137
138 static struct shash_alg ghash_alg = {
139         .digestsize     = GHASH_DIGEST_SIZE,
140         .init           = ghash_init,
141         .update         = ghash_update,
142         .final          = ghash_final,
143         .setkey         = ghash_setkey,
144         .descsize       = sizeof(struct ghash_desc_ctx),
145         .base           = {
146                 .cra_name               = "__ghash",
147                 .cra_driver_name        = "__ghash-pclmulqdqni",
148                 .cra_priority           = 0,
149                 .cra_flags              = CRYPTO_ALG_TYPE_SHASH,
150                 .cra_blocksize          = GHASH_BLOCK_SIZE,
151                 .cra_ctxsize            = sizeof(struct ghash_ctx),
152                 .cra_module             = THIS_MODULE,
153                 .cra_list               = LIST_HEAD_INIT(ghash_alg.base.cra_list),
154         },
155 };
156
157 static int ghash_async_init(struct ahash_request *req)
158 {
159         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
160         struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
161         struct ahash_request *cryptd_req = ahash_request_ctx(req);
162         struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
163
164         if (!irq_fpu_usable()) {
165                 memcpy(cryptd_req, req, sizeof(*req));
166                 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
167                 return crypto_ahash_init(cryptd_req);
168         } else {
169                 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
170                 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
171
172                 desc->tfm = child;
173                 desc->flags = req->base.flags;
174                 return crypto_shash_init(desc);
175         }
176 }
177
178 static int ghash_async_update(struct ahash_request *req)
179 {
180         struct ahash_request *cryptd_req = ahash_request_ctx(req);
181
182         if (!irq_fpu_usable()) {
183                 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
184                 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
185                 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
186
187                 memcpy(cryptd_req, req, sizeof(*req));
188                 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
189                 return crypto_ahash_update(cryptd_req);
190         } else {
191                 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
192                 return shash_ahash_update(req, desc);
193         }
194 }
195
196 static int ghash_async_final(struct ahash_request *req)
197 {
198         struct ahash_request *cryptd_req = ahash_request_ctx(req);
199
200         if (!irq_fpu_usable()) {
201                 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
202                 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
203                 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
204
205                 memcpy(cryptd_req, req, sizeof(*req));
206                 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
207                 return crypto_ahash_final(cryptd_req);
208         } else {
209                 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
210                 return crypto_shash_final(desc, req->result);
211         }
212 }
213
214 static int ghash_async_digest(struct ahash_request *req)
215 {
216         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
217         struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
218         struct ahash_request *cryptd_req = ahash_request_ctx(req);
219         struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
220
221         if (!irq_fpu_usable()) {
222                 memcpy(cryptd_req, req, sizeof(*req));
223                 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
224                 return crypto_ahash_digest(cryptd_req);
225         } else {
226                 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
227                 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
228
229                 desc->tfm = child;
230                 desc->flags = req->base.flags;
231                 return shash_ahash_digest(req, desc);
232         }
233 }
234
235 static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
236                               unsigned int keylen)
237 {
238         struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
239         struct crypto_ahash *child = &ctx->cryptd_tfm->base;
240         int err;
241
242         crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
243         crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
244                                & CRYPTO_TFM_REQ_MASK);
245         err = crypto_ahash_setkey(child, key, keylen);
246         crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
247                                & CRYPTO_TFM_RES_MASK);
248
249         return err;
250 }
251
252 static int ghash_async_init_tfm(struct crypto_tfm *tfm)
253 {
254         struct cryptd_ahash *cryptd_tfm;
255         struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
256
257         cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni", 0, 0);
258         if (IS_ERR(cryptd_tfm))
259                 return PTR_ERR(cryptd_tfm);
260         ctx->cryptd_tfm = cryptd_tfm;
261         crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
262                                  sizeof(struct ahash_request) +
263                                  crypto_ahash_reqsize(&cryptd_tfm->base));
264
265         return 0;
266 }
267
268 static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
269 {
270         struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
271
272         cryptd_free_ahash(ctx->cryptd_tfm);
273 }
274
275 static struct ahash_alg ghash_async_alg = {
276         .init           = ghash_async_init,
277         .update         = ghash_async_update,
278         .final          = ghash_async_final,
279         .setkey         = ghash_async_setkey,
280         .digest         = ghash_async_digest,
281         .halg = {
282                 .digestsize     = GHASH_DIGEST_SIZE,
283                 .base = {
284                         .cra_name               = "ghash",
285                         .cra_driver_name        = "ghash-clmulni",
286                         .cra_priority           = 400,
287                         .cra_flags              = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
288                         .cra_blocksize          = GHASH_BLOCK_SIZE,
289                         .cra_type               = &crypto_ahash_type,
290                         .cra_module             = THIS_MODULE,
291                         .cra_list               = LIST_HEAD_INIT(ghash_async_alg.halg.base.cra_list),
292                         .cra_init               = ghash_async_init_tfm,
293                         .cra_exit               = ghash_async_exit_tfm,
294                 },
295         },
296 };
297
298 static const struct x86_cpu_id pcmul_cpu_id[] = {
299         X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), /* Pickle-Mickle-Duck */
300         {}
301 };
302 MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
303
304 static int __init ghash_pclmulqdqni_mod_init(void)
305 {
306         int err;
307
308         if (!x86_match_cpu(pcmul_cpu_id))
309                 return -ENODEV;
310
311         err = crypto_register_shash(&ghash_alg);
312         if (err)
313                 goto err_out;
314         err = crypto_register_ahash(&ghash_async_alg);
315         if (err)
316                 goto err_shash;
317
318         return 0;
319
320 err_shash:
321         crypto_unregister_shash(&ghash_alg);
322 err_out:
323         return err;
324 }
325
326 static void __exit ghash_pclmulqdqni_mod_exit(void)
327 {
328         crypto_unregister_ahash(&ghash_async_alg);
329         crypto_unregister_shash(&ghash_alg);
330 }
331
332 module_init(ghash_pclmulqdqni_mod_init);
333 module_exit(ghash_pclmulqdqni_mod_exit);
334
335 MODULE_LICENSE("GPL");
336 MODULE_DESCRIPTION("GHASH Message Digest Algorithm, "
337                    "acclerated by PCLMULQDQ-NI");
338 MODULE_ALIAS("ghash");