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>
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 be128 *shash);
30 void clmul_ghash_update(char *dst, const char *src, unsigned int srclen,
33 void clmul_ghash_setkey(be128 *shash, const u8 *key);
35 struct ghash_async_ctx {
36 struct cryptd_ahash *cryptd_tfm;
43 struct ghash_desc_ctx {
44 u8 buffer[GHASH_BLOCK_SIZE];
48 static int ghash_init(struct shash_desc *desc)
50 struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
52 memset(dctx, 0, sizeof(*dctx));
57 static int ghash_setkey(struct crypto_shash *tfm,
58 const u8 *key, unsigned int keylen)
60 struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
62 if (keylen != GHASH_BLOCK_SIZE) {
63 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
67 clmul_ghash_setkey(&ctx->shash, key);
72 static int ghash_update(struct shash_desc *desc,
73 const u8 *src, unsigned int srclen)
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;
81 int n = min(srclen, dctx->bytes);
82 u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
91 clmul_ghash_mul(dst, &ctx->shash);
94 clmul_ghash_update(dst, src, srclen, &ctx->shash);
98 src += srclen - (srclen & 0xf);
100 dctx->bytes = GHASH_BLOCK_SIZE - srclen;
108 static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
110 u8 *dst = dctx->buffer;
113 u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
115 while (dctx->bytes--)
119 clmul_ghash_mul(dst, &ctx->shash);
126 static int ghash_final(struct shash_desc *desc, u8 *dst)
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;
132 ghash_flush(ctx, dctx);
133 memcpy(dst, buf, GHASH_BLOCK_SIZE);
138 static struct shash_alg ghash_alg = {
139 .digestsize = GHASH_DIGEST_SIZE,
141 .update = ghash_update,
142 .final = ghash_final,
143 .setkey = ghash_setkey,
144 .descsize = sizeof(struct ghash_desc_ctx),
146 .cra_name = "__ghash",
147 .cra_driver_name = "__ghash-pclmulqdqni",
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,
156 static int ghash_async_init(struct ahash_request *req)
158 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
159 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
160 struct ahash_request *cryptd_req = ahash_request_ctx(req);
161 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
163 if (!irq_fpu_usable()) {
164 memcpy(cryptd_req, req, sizeof(*req));
165 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
166 return crypto_ahash_init(cryptd_req);
168 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
169 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
172 desc->flags = req->base.flags;
173 return crypto_shash_init(desc);
177 static int ghash_async_update(struct ahash_request *req)
179 struct ahash_request *cryptd_req = ahash_request_ctx(req);
181 if (!irq_fpu_usable()) {
182 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
183 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
184 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
186 memcpy(cryptd_req, req, sizeof(*req));
187 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
188 return crypto_ahash_update(cryptd_req);
190 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
191 return shash_ahash_update(req, desc);
195 static int ghash_async_final(struct ahash_request *req)
197 struct ahash_request *cryptd_req = ahash_request_ctx(req);
199 if (!irq_fpu_usable()) {
200 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
201 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
202 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
204 memcpy(cryptd_req, req, sizeof(*req));
205 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
206 return crypto_ahash_final(cryptd_req);
208 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
209 return crypto_shash_final(desc, req->result);
213 static int ghash_async_digest(struct ahash_request *req)
215 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
216 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
217 struct ahash_request *cryptd_req = ahash_request_ctx(req);
218 struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
220 if (!irq_fpu_usable()) {
221 memcpy(cryptd_req, req, sizeof(*req));
222 ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
223 return crypto_ahash_digest(cryptd_req);
225 struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
226 struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
229 desc->flags = req->base.flags;
230 return shash_ahash_digest(req, desc);
234 static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
237 struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
238 struct crypto_ahash *child = &ctx->cryptd_tfm->base;
241 crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
242 crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
243 & CRYPTO_TFM_REQ_MASK);
244 err = crypto_ahash_setkey(child, key, keylen);
245 crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
246 & CRYPTO_TFM_RES_MASK);
251 static int ghash_async_init_tfm(struct crypto_tfm *tfm)
253 struct cryptd_ahash *cryptd_tfm;
254 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
256 cryptd_tfm = cryptd_alloc_ahash("__ghash-pclmulqdqni", 0, 0);
257 if (IS_ERR(cryptd_tfm))
258 return PTR_ERR(cryptd_tfm);
259 ctx->cryptd_tfm = cryptd_tfm;
260 crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
261 sizeof(struct ahash_request) +
262 crypto_ahash_reqsize(&cryptd_tfm->base));
267 static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
269 struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
271 cryptd_free_ahash(ctx->cryptd_tfm);
274 static struct ahash_alg ghash_async_alg = {
275 .init = ghash_async_init,
276 .update = ghash_async_update,
277 .final = ghash_async_final,
278 .setkey = ghash_async_setkey,
279 .digest = ghash_async_digest,
281 .digestsize = GHASH_DIGEST_SIZE,
284 .cra_driver_name = "ghash-clmulni",
286 .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
287 .cra_blocksize = GHASH_BLOCK_SIZE,
288 .cra_type = &crypto_ahash_type,
289 .cra_module = THIS_MODULE,
290 .cra_init = ghash_async_init_tfm,
291 .cra_exit = ghash_async_exit_tfm,
296 static const struct x86_cpu_id pcmul_cpu_id[] = {
297 X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), /* Pickle-Mickle-Duck */
300 MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
302 static int __init ghash_pclmulqdqni_mod_init(void)
306 if (!x86_match_cpu(pcmul_cpu_id))
309 err = crypto_register_shash(&ghash_alg);
312 err = crypto_register_ahash(&ghash_async_alg);
319 crypto_unregister_shash(&ghash_alg);
324 static void __exit ghash_pclmulqdqni_mod_exit(void)
326 crypto_unregister_ahash(&ghash_async_alg);
327 crypto_unregister_shash(&ghash_alg);
330 module_init(ghash_pclmulqdqni_mod_init);
331 module_exit(ghash_pclmulqdqni_mod_exit);
333 MODULE_LICENSE("GPL");
334 MODULE_DESCRIPTION("GHASH Message Digest Algorithm, "
335 "acclerated by PCLMULQDQ-NI");
336 MODULE_ALIAS("ghash");