Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Asynchronous block chaining cipher operations.
3 *
4 * This is the asynchronous version of blkcipher.c indicating completion
5 * via a callback.
6 *
7 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 *
14 */
15
16#include <crypto/internal/skcipher.h>
17#include <linux/err.h>
18#include <linux/init.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/rtnetlink.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24#include <linux/seq_file.h>
25
26#include "internal.h"
27
28static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key,
29 unsigned int keylen)
30{
31 struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
32 unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
33 int ret;
34 u8 *buffer, *alignbuffer;
35 unsigned long absize;
36
37 absize = keylen + alignmask;
38 buffer = kmalloc(absize, GFP_ATOMIC);
39 if (!buffer)
40 return -ENOMEM;
41
42 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
43 memcpy(alignbuffer, key, keylen);
44 ret = cipher->setkey(tfm, alignbuffer, keylen);
45 memset(alignbuffer, 0, keylen);
46 kfree(buffer);
47 return ret;
48}
49
50static int setkey(struct crypto_ablkcipher *tfm, const u8 *key,
51 unsigned int keylen)
52{
53 struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm);
54 unsigned long alignmask = crypto_ablkcipher_alignmask(tfm);
55
56 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
57 crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
58 return -EINVAL;
59 }
60
61 if ((unsigned long)key & alignmask)
62 return setkey_unaligned(tfm, key, keylen);
63
64 return cipher->setkey(tfm, key, keylen);
65}
66
67static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type,
68 u32 mask)
69{
70 return alg->cra_ctxsize;
71}
72
73int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req)
74{
75 return crypto_ablkcipher_encrypt(&req->creq);
76}
77
78int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req)
79{
80 return crypto_ablkcipher_decrypt(&req->creq);
81}
82
83static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type,
84 u32 mask)
85{
86 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
87 struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
88
89 if (alg->ivsize > PAGE_SIZE / 8)
90 return -EINVAL;
91
92 crt->setkey = setkey;
93 crt->encrypt = alg->encrypt;
94 crt->decrypt = alg->decrypt;
95 if (!alg->ivsize) {
96 crt->givencrypt = skcipher_null_givencrypt;
97 crt->givdecrypt = skcipher_null_givdecrypt;
98 }
99 crt->base = __crypto_ablkcipher_cast(tfm);
100 crt->ivsize = alg->ivsize;
101
102 return 0;
103}
104
105static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
106 __attribute__ ((unused));
107static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg)
108{
109 struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
110
111 seq_printf(m, "type : ablkcipher\n");
112 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
113 "yes" : "no");
114 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
115 seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
116 seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
117 seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
118 seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>");
119}
120
121const struct crypto_type crypto_ablkcipher_type = {
122 .ctxsize = crypto_ablkcipher_ctxsize,
123 .init = crypto_init_ablkcipher_ops,
124#ifdef CONFIG_PROC_FS
125 .show = crypto_ablkcipher_show,
126#endif
127};
128EXPORT_SYMBOL_GPL(crypto_ablkcipher_type);
129
130static int no_givdecrypt(struct skcipher_givcrypt_request *req)
131{
132 return -ENOSYS;
133}
134
135static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type,
136 u32 mask)
137{
138 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
139 struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
140
141 if (alg->ivsize > PAGE_SIZE / 8)
142 return -EINVAL;
143
144 crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ?
145 alg->setkey : setkey;
146 crt->encrypt = alg->encrypt;
147 crt->decrypt = alg->decrypt;
148 crt->givencrypt = alg->givencrypt;
149 crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt;
150 crt->base = __crypto_ablkcipher_cast(tfm);
151 crt->ivsize = alg->ivsize;
152
153 return 0;
154}
155
156static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
157 __attribute__ ((unused));
158static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg)
159{
160 struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher;
161
162 seq_printf(m, "type : givcipher\n");
163 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
164 "yes" : "no");
165 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
166 seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize);
167 seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize);
168 seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize);
169 seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>");
170}
171
172const struct crypto_type crypto_givcipher_type = {
173 .ctxsize = crypto_ablkcipher_ctxsize,
174 .init = crypto_init_givcipher_ops,
175#ifdef CONFIG_PROC_FS
176 .show = crypto_givcipher_show,
177#endif
178};
179EXPORT_SYMBOL_GPL(crypto_givcipher_type);
180
181const char *crypto_default_geniv(const struct crypto_alg *alg)
182{
183 return alg->cra_flags & CRYPTO_ALG_ASYNC ? "eseqiv" : "chainiv";
184}
185
186static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask)
187{
188 struct rtattr *tb[3];
189 struct {
190 struct rtattr attr;
191 struct crypto_attr_type data;
192 } ptype;
193 struct {
194 struct rtattr attr;
195 struct crypto_attr_alg data;
196 } palg;
197 struct crypto_template *tmpl;
198 struct crypto_instance *inst;
199 struct crypto_alg *larval;
200 const char *geniv;
201 int err;
202
203 larval = crypto_larval_lookup(alg->cra_driver_name,
204 CRYPTO_ALG_TYPE_GIVCIPHER,
205 CRYPTO_ALG_TYPE_MASK);
206 err = PTR_ERR(larval);
207 if (IS_ERR(larval))
208 goto out;
209
210 err = -EAGAIN;
211 if (!crypto_is_larval(larval))
212 goto drop_larval;
213
214 ptype.attr.rta_len = sizeof(ptype);
215 ptype.attr.rta_type = CRYPTOA_TYPE;
216 ptype.data.type = type | CRYPTO_ALG_GENIV;
217 /* GENIV tells the template that we're making a default geniv. */
218 ptype.data.mask = mask | CRYPTO_ALG_GENIV;
219 tb[0] = &ptype.attr;
220
221 palg.attr.rta_len = sizeof(palg);
222 palg.attr.rta_type = CRYPTOA_ALG;
223 /* Must use the exact name to locate ourselves. */
224 memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
225 tb[1] = &palg.attr;
226
227 tb[2] = NULL;
228
229 if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
230 CRYPTO_ALG_TYPE_BLKCIPHER)
231 geniv = alg->cra_blkcipher.geniv;
232 else
233 geniv = alg->cra_ablkcipher.geniv;
234
235 if (!geniv)
236 geniv = crypto_default_geniv(alg);
237
238 tmpl = crypto_lookup_template(geniv);
239 err = -ENOENT;
240 if (!tmpl)
241 goto kill_larval;
242
243 inst = tmpl->alloc(tb);
244 err = PTR_ERR(inst);
245 if (IS_ERR(inst))
246 goto put_tmpl;
247
248 if ((err = crypto_register_instance(tmpl, inst))) {
249 tmpl->free(inst);
250 goto put_tmpl;
251 }
252
253 /* Redo the lookup to use the instance we just registered. */
254 err = -EAGAIN;
255
256put_tmpl:
257 crypto_tmpl_put(tmpl);
258kill_larval:
259 crypto_larval_kill(larval);
260drop_larval:
261 crypto_mod_put(larval);
262out:
263 crypto_mod_put(alg);
264 return err;
265}
266
267static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type,
268 u32 mask)
269{
270 struct crypto_alg *alg;
271
272 alg = crypto_alg_mod_lookup(name, type, mask);
273 if (IS_ERR(alg))
274 return alg;
275
276 if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
277 CRYPTO_ALG_TYPE_GIVCIPHER)
278 return alg;
279
280 if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
281 CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize :
282 alg->cra_ablkcipher.ivsize))
283 return alg;
284
285 return ERR_PTR(crypto_givcipher_default(alg, type, mask));
286}
287
288int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
289 u32 type, u32 mask)
290{
291 struct crypto_alg *alg;
292 int err;
293
294 type = crypto_skcipher_type(type);
295 mask = crypto_skcipher_mask(mask);
296
297 alg = crypto_lookup_skcipher(name, type, mask);
298 if (IS_ERR(alg))
299 return PTR_ERR(alg);
300
301 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
302 crypto_mod_put(alg);
303 return err;
304}
305EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
306
307struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
308 u32 type, u32 mask)
309{
310 struct crypto_tfm *tfm;
311 int err;
312
313 type = crypto_skcipher_type(type);
314 mask = crypto_skcipher_mask(mask);
315
316 for (;;) {
317 struct crypto_alg *alg;
318
319 alg = crypto_lookup_skcipher(alg_name, type, mask);
320 if (IS_ERR(alg)) {
321 err = PTR_ERR(alg);
322 goto err;
323 }
324
325 tfm = __crypto_alloc_tfm(alg, type, mask);
326 if (!IS_ERR(tfm))
327 return __crypto_ablkcipher_cast(tfm);
328
329 crypto_mod_put(alg);
330 err = PTR_ERR(tfm);
331
332err:
333 if (err != -EAGAIN)
334 break;
335 if (signal_pending(current)) {
336 err = -EINTR;
337 break;
338 }
339 }
340
341 return ERR_PTR(err);
342}
343EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher);