crypto: prefix module autoloading with "crypto-"
[linux-2.6/btrfs-unstable.git] / arch / x86 / crypto / ghash-clmulni-intel_glue.c
blob8253d85aa16508f19249e1f3cee91356c565d1e3
1 /*
2 * Accelerated GHASH implementation with Intel PCLMULQDQ-NI
3 * instructions. This file contains glue code.
5 * Copyright (c) 2009 Intel Corp.
6 * Author: Huang Ying <ying.huang@intel.com>
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.
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>
25 #define GHASH_BLOCK_SIZE 16
26 #define GHASH_DIGEST_SIZE 16
28 void clmul_ghash_mul(char *dst, const u128 *shash);
30 void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
31 const u128 *shash);
33 struct ghash_async_ctx {
34 struct cryptd_ahash *cryptd_tfm;
37 struct ghash_ctx {
38 u128 shash;
41 struct ghash_desc_ctx {
42 u8 buffer[GHASH_BLOCK_SIZE];
43 u32 bytes;
46 static int ghash_init(struct shash_desc *desc)
48 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
50 memset(dctx, 0, sizeof(*dctx));
52 return 0;
55 static int ghash_setkey(struct crypto_shash *tfm,
56 const u8 *key, unsigned int keylen)
58 struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
59 be128 *x = (be128 *)key;
60 u64 a, b;
62 if (keylen != GHASH_BLOCK_SIZE) {
63 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
64 return -EINVAL;
67 /* perform multiplication by 'x' in GF(2^128) */
68 a = be64_to_cpu(x->a);
69 b = be64_to_cpu(x->b);
71 ctx->shash.a = (b << 1) | (a >> 63);
72 ctx->shash.b = (a << 1) | (b >> 63);
74 if (a >> 63)
75 ctx->shash.b ^= ((u64)0xc2) << 56;
77 return 0;
80 static int ghash_update(struct shash_desc *desc,
81 const u8 *src, unsigned int srclen)
83 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
84 struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
85 u8 *dst = dctx->buffer;
87 kernel_fpu_begin();
88 if (dctx->bytes) {
89 int n = min(srclen, dctx->bytes);
90 u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
92 dctx->bytes -= n;
93 srclen -= n;
95 while (n--)
96 *pos++ ^= *src++;
98 if (!dctx->bytes)
99 clmul_ghash_mul(dst, &ctx->shash);
102 clmul_ghash_update(dst, src, srclen, &ctx->shash);
103 kernel_fpu_end();
105 if (srclen & 0xf) {
106 src += srclen - (srclen & 0xf);
107 srclen &= 0xf;
108 dctx->bytes = GHASH_BLOCK_SIZE - srclen;
109 while (srclen--)
110 *dst++ ^= *src++;
113 return 0;
116 static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
118 u8 *dst = dctx->buffer;
120 if (dctx->bytes) {
121 u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
123 while (dctx->bytes--)
124 *tmp++ ^= 0;
126 kernel_fpu_begin();
127 clmul_ghash_mul(dst, &ctx->shash);
128 kernel_fpu_end();
131 dctx->bytes = 0;
134 static int ghash_final(struct shash_desc *desc, u8 *dst)
136 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
137 struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
138 u8 *buf = dctx->buffer;
140 ghash_flush(ctx, dctx);
141 memcpy(dst, buf, GHASH_BLOCK_SIZE);
143 return 0;
146 static struct shash_alg ghash_alg = {
147 .digestsize = GHASH_DIGEST_SIZE,
148 .init = ghash_init,
149 .update = ghash_update,
150 .final = ghash_final,
151 .setkey = ghash_setkey,
152 .descsize = sizeof(struct ghash_desc_ctx),
153 .base = {
154 .cra_name = "__ghash",
155 .cra_driver_name = "__ghash-pclmulqdqni",
156 .cra_priority = 0,
157 .cra_flags = CRYPTO_ALG_TYPE_SHASH,
158 .cra_blocksize = GHASH_BLOCK_SIZE,
159 .cra_ctxsize = sizeof(struct ghash_ctx),
160 .cra_module = THIS_MODULE,
164 static int ghash_async_init(struct ahash_request *req)
166 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
167 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
168 struct ahash_request *cryptd_req = ahash_request_ctx(req);
169 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
171 if (!irq_fpu_usable()) {
172 memcpy(cryptd_req, req, sizeof(*req));
173 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
174 return crypto_ahash_init(cryptd_req);
175 } else {
176 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
177 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
179 desc->tfm = child;
180 desc->flags = req->base.flags;
181 return crypto_shash_init(desc);
185 static int ghash_async_update(struct ahash_request *req)
187 struct ahash_request *cryptd_req = ahash_request_ctx(req);
189 if (!irq_fpu_usable()) {
190 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
191 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
192 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
194 memcpy(cryptd_req, req, sizeof(*req));
195 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
196 return crypto_ahash_update(cryptd_req);
197 } else {
198 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
199 return shash_ahash_update(req, desc);
203 static int ghash_async_final(struct ahash_request *req)
205 struct ahash_request *cryptd_req = ahash_request_ctx(req);
207 if (!irq_fpu_usable()) {
208 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
209 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
210 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
212 memcpy(cryptd_req, req, sizeof(*req));
213 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
214 return crypto_ahash_final(cryptd_req);
215 } else {
216 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
217 return crypto_shash_final(desc, req->result);
221 static int ghash_async_digest(struct ahash_request *req)
223 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
224 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
225 struct ahash_request *cryptd_req = ahash_request_ctx(req);
226 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
228 if (!irq_fpu_usable()) {
229 memcpy(cryptd_req, req, sizeof(*req));
230 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
231 return crypto_ahash_digest(cryptd_req);
232 } else {
233 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
234 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
236 desc->tfm = child;
237 desc->flags = req->base.flags;
238 return shash_ahash_digest(req, desc);
242 static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
243 unsigned int keylen)
245 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
246 struct crypto_ahash *child = &ctx->cryptd_tfm->base;
247 int err;
249 crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
250 crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
251 & CRYPTO_TFM_REQ_MASK);
252 err = crypto_ahash_setkey(child, key, keylen);
253 crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
254 & CRYPTO_TFM_RES_MASK);
256 return err;
259 static int ghash_async_init_tfm(struct crypto_tfm *tfm)
261 struct cryptd_ahash *cryptd_tfm;
262 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
264 cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni", 0, 0);
265 if (IS_ERR(cryptd_tfm))
266 return PTR_ERR(cryptd_tfm);
267 ctx->cryptd_tfm = cryptd_tfm;
268 crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
269 sizeof(struct ahash_request) +
270 crypto_ahash_reqsize(&cryptd_tfm->base));
272 return 0;
275 static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
277 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
279 cryptd_free_ahash(ctx->cryptd_tfm);
282 static struct ahash_alg ghash_async_alg = {
283 .init = ghash_async_init,
284 .update = ghash_async_update,
285 .final = ghash_async_final,
286 .setkey = ghash_async_setkey,
287 .digest = ghash_async_digest,
288 .halg = {
289 .digestsize = GHASH_DIGEST_SIZE,
290 .base = {
291 .cra_name = "ghash",
292 .cra_driver_name = "ghash-clmulni",
293 .cra_priority = 400,
294 .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
295 .cra_blocksize = GHASH_BLOCK_SIZE,
296 .cra_type = &crypto_ahash_type,
297 .cra_module = THIS_MODULE,
298 .cra_init = ghash_async_init_tfm,
299 .cra_exit = ghash_async_exit_tfm,
304 static const struct x86_cpu_id pcmul_cpu_id[] = {
305 X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), /* Pickle-Mickle-Duck */
308 MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
310 static int __init ghash_pclmulqdqni_mod_init(void)
312 int err;
314 if (!x86_match_cpu(pcmul_cpu_id))
315 return -ENODEV;
317 err = crypto_register_shash(&ghash_alg);
318 if (err)
319 goto err_out;
320 err = crypto_register_ahash(&ghash_async_alg);
321 if (err)
322 goto err_shash;
324 return 0;
326 err_shash:
327 crypto_unregister_shash(&ghash_alg);
328 err_out:
329 return err;
332 static void __exit ghash_pclmulqdqni_mod_exit(void)
334 crypto_unregister_ahash(&ghash_async_alg);
335 crypto_unregister_shash(&ghash_alg);
338 module_init(ghash_pclmulqdqni_mod_init);
339 module_exit(ghash_pclmulqdqni_mod_exit);
341 MODULE_LICENSE("GPL");
342 MODULE_DESCRIPTION("GHASH Message Digest Algorithm, "
343 "acclerated by PCLMULQDQ-NI");
344 MODULE_ALIAS_CRYPTO("ghash");