1 /*
2  * Shared crypto simd helpers
3  *
4  * Copyright (c) 2012 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
5  * Copyright (c) 2016 Herbert Xu <herbert@gondor.apana.org.au>
6  *
7  * Based on aesni-intel_glue.c by:
8  *  Copyright (C) 2008, Intel Corp.
9  *    Author: Huang Ying <ying.huang@intel.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
23  *
24  */
25 
26 #include <crypto/cryptd.h>
27 #include <crypto/internal/simd.h>
28 #include <crypto/internal/skcipher.h>
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/preempt.h>
32 #include <asm/simd.h>
33 
34 struct simd_skcipher_alg {
35 	const char *ialg_name;
36 	struct skcipher_alg alg;
37 };
38 
39 struct simd_skcipher_ctx {
40 	struct cryptd_skcipher *cryptd_tfm;
41 };
42 
simd_skcipher_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int key_len)43 static int simd_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
44 				unsigned int key_len)
45 {
46 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
47 	struct crypto_skcipher *child = &ctx->cryptd_tfm->base;
48 	int err;
49 
50 	crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
51 	crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(tfm) &
52 					 CRYPTO_TFM_REQ_MASK);
53 	err = crypto_skcipher_setkey(child, key, key_len);
54 	crypto_skcipher_set_flags(tfm, crypto_skcipher_get_flags(child) &
55 				       CRYPTO_TFM_RES_MASK);
56 	return err;
57 }
58 
simd_skcipher_encrypt(struct skcipher_request * req)59 static int simd_skcipher_encrypt(struct skcipher_request *req)
60 {
61 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
62 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
63 	struct skcipher_request *subreq;
64 	struct crypto_skcipher *child;
65 
66 	subreq = skcipher_request_ctx(req);
67 	*subreq = *req;
68 
69 	if (!may_use_simd() ||
70 	    (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
71 		child = &ctx->cryptd_tfm->base;
72 	else
73 		child = cryptd_skcipher_child(ctx->cryptd_tfm);
74 
75 	skcipher_request_set_tfm(subreq, child);
76 
77 	return crypto_skcipher_encrypt(subreq);
78 }
79 
simd_skcipher_decrypt(struct skcipher_request * req)80 static int simd_skcipher_decrypt(struct skcipher_request *req)
81 {
82 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
83 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
84 	struct skcipher_request *subreq;
85 	struct crypto_skcipher *child;
86 
87 	subreq = skcipher_request_ctx(req);
88 	*subreq = *req;
89 
90 	if (!may_use_simd() ||
91 	    (in_atomic() && cryptd_skcipher_queued(ctx->cryptd_tfm)))
92 		child = &ctx->cryptd_tfm->base;
93 	else
94 		child = cryptd_skcipher_child(ctx->cryptd_tfm);
95 
96 	skcipher_request_set_tfm(subreq, child);
97 
98 	return crypto_skcipher_decrypt(subreq);
99 }
100 
simd_skcipher_exit(struct crypto_skcipher * tfm)101 static void simd_skcipher_exit(struct crypto_skcipher *tfm)
102 {
103 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
104 
105 	cryptd_free_skcipher(ctx->cryptd_tfm);
106 }
107 
simd_skcipher_init(struct crypto_skcipher * tfm)108 static int simd_skcipher_init(struct crypto_skcipher *tfm)
109 {
110 	struct simd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
111 	struct cryptd_skcipher *cryptd_tfm;
112 	struct simd_skcipher_alg *salg;
113 	struct skcipher_alg *alg;
114 	unsigned reqsize;
115 
116 	alg = crypto_skcipher_alg(tfm);
117 	salg = container_of(alg, struct simd_skcipher_alg, alg);
118 
119 	cryptd_tfm = cryptd_alloc_skcipher(salg->ialg_name,
120 					   CRYPTO_ALG_INTERNAL,
121 					   CRYPTO_ALG_INTERNAL);
122 	if (IS_ERR(cryptd_tfm))
123 		return PTR_ERR(cryptd_tfm);
124 
125 	ctx->cryptd_tfm = cryptd_tfm;
126 
127 	reqsize = sizeof(struct skcipher_request);
128 	reqsize += crypto_skcipher_reqsize(&cryptd_tfm->base);
129 
130 	crypto_skcipher_set_reqsize(tfm, reqsize);
131 
132 	return 0;
133 }
134 
simd_skcipher_create_compat(const char * algname,const char * drvname,const char * basename)135 struct simd_skcipher_alg *simd_skcipher_create_compat(const char *algname,
136 						      const char *drvname,
137 						      const char *basename)
138 {
139 	struct simd_skcipher_alg *salg;
140 	struct crypto_skcipher *tfm;
141 	struct skcipher_alg *ialg;
142 	struct skcipher_alg *alg;
143 	int err;
144 
145 	tfm = crypto_alloc_skcipher(basename, CRYPTO_ALG_INTERNAL,
146 				    CRYPTO_ALG_INTERNAL | CRYPTO_ALG_ASYNC);
147 	if (IS_ERR(tfm))
148 		return ERR_CAST(tfm);
149 
150 	ialg = crypto_skcipher_alg(tfm);
151 
152 	salg = kzalloc(sizeof(*salg), GFP_KERNEL);
153 	if (!salg) {
154 		salg = ERR_PTR(-ENOMEM);
155 		goto out_put_tfm;
156 	}
157 
158 	salg->ialg_name = basename;
159 	alg = &salg->alg;
160 
161 	err = -ENAMETOOLONG;
162 	if (snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", algname) >=
163 	    CRYPTO_MAX_ALG_NAME)
164 		goto out_free_salg;
165 
166 	if (snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
167 		     drvname) >= CRYPTO_MAX_ALG_NAME)
168 		goto out_free_salg;
169 
170 	alg->base.cra_flags = CRYPTO_ALG_ASYNC;
171 	alg->base.cra_priority = ialg->base.cra_priority;
172 	alg->base.cra_blocksize = ialg->base.cra_blocksize;
173 	alg->base.cra_alignmask = ialg->base.cra_alignmask;
174 	alg->base.cra_module = ialg->base.cra_module;
175 	alg->base.cra_ctxsize = sizeof(struct simd_skcipher_ctx);
176 
177 	alg->ivsize = ialg->ivsize;
178 	alg->chunksize = ialg->chunksize;
179 	alg->min_keysize = ialg->min_keysize;
180 	alg->max_keysize = ialg->max_keysize;
181 
182 	alg->init = simd_skcipher_init;
183 	alg->exit = simd_skcipher_exit;
184 
185 	alg->setkey = simd_skcipher_setkey;
186 	alg->encrypt = simd_skcipher_encrypt;
187 	alg->decrypt = simd_skcipher_decrypt;
188 
189 	err = crypto_register_skcipher(alg);
190 	if (err)
191 		goto out_free_salg;
192 
193 out_put_tfm:
194 	crypto_free_skcipher(tfm);
195 	return salg;
196 
197 out_free_salg:
198 	kfree(salg);
199 	salg = ERR_PTR(err);
200 	goto out_put_tfm;
201 }
202 EXPORT_SYMBOL_GPL(simd_skcipher_create_compat);
203 
simd_skcipher_create(const char * algname,const char * basename)204 struct simd_skcipher_alg *simd_skcipher_create(const char *algname,
205 					       const char *basename)
206 {
207 	char drvname[CRYPTO_MAX_ALG_NAME];
208 
209 	if (snprintf(drvname, CRYPTO_MAX_ALG_NAME, "simd-%s", basename) >=
210 	    CRYPTO_MAX_ALG_NAME)
211 		return ERR_PTR(-ENAMETOOLONG);
212 
213 	return simd_skcipher_create_compat(algname, drvname, basename);
214 }
215 EXPORT_SYMBOL_GPL(simd_skcipher_create);
216 
simd_skcipher_free(struct simd_skcipher_alg * salg)217 void simd_skcipher_free(struct simd_skcipher_alg *salg)
218 {
219 	crypto_unregister_skcipher(&salg->alg);
220 	kfree(salg);
221 }
222 EXPORT_SYMBOL_GPL(simd_skcipher_free);
223 
simd_register_skciphers_compat(struct skcipher_alg * algs,int count,struct simd_skcipher_alg ** simd_algs)224 int simd_register_skciphers_compat(struct skcipher_alg *algs, int count,
225 				   struct simd_skcipher_alg **simd_algs)
226 {
227 	int err;
228 	int i;
229 	const char *algname;
230 	const char *drvname;
231 	const char *basename;
232 	struct simd_skcipher_alg *simd;
233 
234 	err = crypto_register_skciphers(algs, count);
235 	if (err)
236 		return err;
237 
238 	for (i = 0; i < count; i++) {
239 		WARN_ON(strncmp(algs[i].base.cra_name, "__", 2));
240 		WARN_ON(strncmp(algs[i].base.cra_driver_name, "__", 2));
241 		algname = algs[i].base.cra_name + 2;
242 		drvname = algs[i].base.cra_driver_name + 2;
243 		basename = algs[i].base.cra_driver_name;
244 		simd = simd_skcipher_create_compat(algname, drvname, basename);
245 		err = PTR_ERR(simd);
246 		if (IS_ERR(simd))
247 			goto err_unregister;
248 		simd_algs[i] = simd;
249 	}
250 	return 0;
251 
252 err_unregister:
253 	simd_unregister_skciphers(algs, count, simd_algs);
254 	return err;
255 }
256 EXPORT_SYMBOL_GPL(simd_register_skciphers_compat);
257 
simd_unregister_skciphers(struct skcipher_alg * algs,int count,struct simd_skcipher_alg ** simd_algs)258 void simd_unregister_skciphers(struct skcipher_alg *algs, int count,
259 			       struct simd_skcipher_alg **simd_algs)
260 {
261 	int i;
262 
263 	crypto_unregister_skciphers(algs, count);
264 
265 	for (i = 0; i < count; i++) {
266 		if (simd_algs[i]) {
267 			simd_skcipher_free(simd_algs[i]);
268 			simd_algs[i] = NULL;
269 		}
270 	}
271 }
272 EXPORT_SYMBOL_GPL(simd_unregister_skciphers);
273 
274 MODULE_LICENSE("GPL");
275