Commit | Line | Data |
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a38f7907 SK |
1 | /* |
2 | * Crypto user configuration API. | |
3 | * | |
4 | * Copyright (C) 2011 secunet Security Networks AG | |
5 | * Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms and conditions of the GNU General Public License, | |
9 | * version 2, as published by the Free Software Foundation. | |
10 | * | |
11 | * This program is distributed in the hope it will be useful, but WITHOUT | |
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
14 | * more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along with | |
17 | * this program; if not, write to the Free Software Foundation, Inc., | |
18 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
19 | */ | |
20 | ||
21 | #include <linux/module.h> | |
22 | #include <linux/crypto.h> | |
23 | #include <linux/cryptouser.h> | |
1e122994 | 24 | #include <linux/sched.h> |
a38f7907 SK |
25 | #include <net/netlink.h> |
26 | #include <linux/security.h> | |
27 | #include <net/net_namespace.h> | |
1e122994 SK |
28 | #include <crypto/internal/aead.h> |
29 | #include <crypto/internal/skcipher.h> | |
30 | ||
a38f7907 SK |
31 | #include "internal.h" |
32 | ||
33 | DEFINE_MUTEX(crypto_cfg_mutex); | |
34 | ||
35 | /* The crypto netlink socket */ | |
36 | static struct sock *crypto_nlsk; | |
37 | ||
38 | struct crypto_dump_info { | |
39 | struct sk_buff *in_skb; | |
40 | struct sk_buff *out_skb; | |
41 | u32 nlmsg_seq; | |
42 | u16 nlmsg_flags; | |
43 | }; | |
44 | ||
45 | static struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact) | |
46 | { | |
a38f7907 SK |
47 | struct crypto_alg *q, *alg = NULL; |
48 | ||
49 | down_read(&crypto_alg_sem); | |
50 | ||
a38f7907 | 51 | list_for_each_entry(q, &crypto_alg_list, cra_list) { |
e6ea64ec | 52 | int match = 0; |
a38f7907 SK |
53 | |
54 | if ((q->cra_flags ^ p->cru_type) & p->cru_mask) | |
55 | continue; | |
56 | ||
57 | if (strlen(p->cru_driver_name)) | |
58 | match = !strcmp(q->cra_driver_name, | |
59 | p->cru_driver_name); | |
60 | else if (!exact) | |
61 | match = !strcmp(q->cra_name, p->cru_name); | |
62 | ||
63 | if (match) { | |
64 | alg = q; | |
65 | break; | |
66 | } | |
67 | } | |
68 | ||
69 | up_read(&crypto_alg_sem); | |
70 | ||
71 | return alg; | |
72 | } | |
73 | ||
07a5fa4a SK |
74 | static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg) |
75 | { | |
76 | struct crypto_report_cipher rcipher; | |
77 | ||
78 | snprintf(rcipher.type, CRYPTO_MAX_ALG_NAME, "%s", "cipher"); | |
79 | ||
80 | rcipher.blocksize = alg->cra_blocksize; | |
81 | rcipher.min_keysize = alg->cra_cipher.cia_min_keysize; | |
82 | rcipher.max_keysize = alg->cra_cipher.cia_max_keysize; | |
83 | ||
6662df33 DM |
84 | if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER, |
85 | sizeof(struct crypto_report_cipher), &rcipher)) | |
86 | goto nla_put_failure; | |
07a5fa4a SK |
87 | return 0; |
88 | ||
89 | nla_put_failure: | |
90 | return -EMSGSIZE; | |
91 | } | |
92 | ||
540b97c1 SK |
93 | static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg) |
94 | { | |
95 | struct crypto_report_comp rcomp; | |
96 | ||
97 | snprintf(rcomp.type, CRYPTO_MAX_ALG_NAME, "%s", "compression"); | |
98 | ||
6662df33 DM |
99 | if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS, |
100 | sizeof(struct crypto_report_comp), &rcomp)) | |
101 | goto nla_put_failure; | |
540b97c1 SK |
102 | return 0; |
103 | ||
104 | nla_put_failure: | |
105 | return -EMSGSIZE; | |
106 | } | |
107 | ||
a38f7907 SK |
108 | static int crypto_report_one(struct crypto_alg *alg, |
109 | struct crypto_user_alg *ualg, struct sk_buff *skb) | |
110 | { | |
111 | memcpy(&ualg->cru_name, &alg->cra_name, sizeof(ualg->cru_name)); | |
112 | memcpy(&ualg->cru_driver_name, &alg->cra_driver_name, | |
113 | sizeof(ualg->cru_driver_name)); | |
114 | memcpy(&ualg->cru_module_name, module_name(alg->cra_module), | |
115 | CRYPTO_MAX_ALG_NAME); | |
116 | ||
117 | ualg->cru_flags = alg->cra_flags; | |
118 | ualg->cru_refcnt = atomic_read(&alg->cra_refcnt); | |
119 | ||
6662df33 DM |
120 | if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority)) |
121 | goto nla_put_failure; | |
6c5a86f5 SK |
122 | if (alg->cra_flags & CRYPTO_ALG_LARVAL) { |
123 | struct crypto_report_larval rl; | |
124 | ||
125 | snprintf(rl.type, CRYPTO_MAX_ALG_NAME, "%s", "larval"); | |
126 | ||
6662df33 DM |
127 | if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL, |
128 | sizeof(struct crypto_report_larval), &rl)) | |
129 | goto nla_put_failure; | |
6c5a86f5 SK |
130 | goto out; |
131 | } | |
132 | ||
b6aa63c0 SK |
133 | if (alg->cra_type && alg->cra_type->report) { |
134 | if (alg->cra_type->report(skb, alg)) | |
135 | goto nla_put_failure; | |
07a5fa4a SK |
136 | |
137 | goto out; | |
138 | } | |
139 | ||
140 | switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_LARVAL)) { | |
141 | case CRYPTO_ALG_TYPE_CIPHER: | |
142 | if (crypto_report_cipher(skb, alg)) | |
143 | goto nla_put_failure; | |
144 | ||
540b97c1 SK |
145 | break; |
146 | case CRYPTO_ALG_TYPE_COMPRESS: | |
147 | if (crypto_report_comp(skb, alg)) | |
148 | goto nla_put_failure; | |
149 | ||
07a5fa4a | 150 | break; |
b6aa63c0 SK |
151 | } |
152 | ||
6c5a86f5 | 153 | out: |
a38f7907 SK |
154 | return 0; |
155 | ||
156 | nla_put_failure: | |
157 | return -EMSGSIZE; | |
158 | } | |
159 | ||
160 | static int crypto_report_alg(struct crypto_alg *alg, | |
161 | struct crypto_dump_info *info) | |
162 | { | |
163 | struct sk_buff *in_skb = info->in_skb; | |
164 | struct sk_buff *skb = info->out_skb; | |
165 | struct nlmsghdr *nlh; | |
166 | struct crypto_user_alg *ualg; | |
167 | int err = 0; | |
168 | ||
169 | nlh = nlmsg_put(skb, NETLINK_CB(in_skb).pid, info->nlmsg_seq, | |
170 | CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags); | |
171 | if (!nlh) { | |
172 | err = -EMSGSIZE; | |
173 | goto out; | |
174 | } | |
175 | ||
176 | ualg = nlmsg_data(nlh); | |
177 | ||
178 | err = crypto_report_one(alg, ualg, skb); | |
179 | if (err) { | |
180 | nlmsg_cancel(skb, nlh); | |
181 | goto out; | |
182 | } | |
183 | ||
184 | nlmsg_end(skb, nlh); | |
185 | ||
186 | out: | |
187 | return err; | |
188 | } | |
189 | ||
190 | static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh, | |
191 | struct nlattr **attrs) | |
192 | { | |
193 | struct crypto_user_alg *p = nlmsg_data(in_nlh); | |
194 | struct crypto_alg *alg; | |
195 | struct sk_buff *skb; | |
196 | struct crypto_dump_info info; | |
197 | int err; | |
198 | ||
199 | if (!p->cru_driver_name) | |
200 | return -EINVAL; | |
201 | ||
202 | alg = crypto_alg_match(p, 1); | |
203 | if (!alg) | |
204 | return -ENOENT; | |
205 | ||
206 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); | |
207 | if (!skb) | |
208 | return -ENOMEM; | |
209 | ||
210 | info.in_skb = in_skb; | |
211 | info.out_skb = skb; | |
212 | info.nlmsg_seq = in_nlh->nlmsg_seq; | |
213 | info.nlmsg_flags = 0; | |
214 | ||
215 | err = crypto_report_alg(alg, &info); | |
216 | if (err) | |
217 | return err; | |
218 | ||
219 | return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).pid); | |
220 | } | |
221 | ||
222 | static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb) | |
223 | { | |
224 | struct crypto_alg *alg; | |
225 | struct crypto_dump_info info; | |
226 | int err; | |
227 | ||
228 | if (cb->args[0]) | |
229 | goto out; | |
230 | ||
231 | cb->args[0] = 1; | |
232 | ||
233 | info.in_skb = cb->skb; | |
234 | info.out_skb = skb; | |
235 | info.nlmsg_seq = cb->nlh->nlmsg_seq; | |
236 | info.nlmsg_flags = NLM_F_MULTI; | |
237 | ||
238 | list_for_each_entry(alg, &crypto_alg_list, cra_list) { | |
239 | err = crypto_report_alg(alg, &info); | |
240 | if (err) | |
241 | goto out_err; | |
242 | } | |
243 | ||
244 | out: | |
245 | return skb->len; | |
246 | out_err: | |
247 | return err; | |
248 | } | |
249 | ||
250 | static int crypto_dump_report_done(struct netlink_callback *cb) | |
251 | { | |
252 | return 0; | |
253 | } | |
254 | ||
255 | static int crypto_update_alg(struct sk_buff *skb, struct nlmsghdr *nlh, | |
256 | struct nlattr **attrs) | |
257 | { | |
258 | struct crypto_alg *alg; | |
259 | struct crypto_user_alg *p = nlmsg_data(nlh); | |
260 | struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL]; | |
261 | LIST_HEAD(list); | |
262 | ||
263 | if (priority && !strlen(p->cru_driver_name)) | |
264 | return -EINVAL; | |
265 | ||
266 | alg = crypto_alg_match(p, 1); | |
267 | if (!alg) | |
268 | return -ENOENT; | |
269 | ||
270 | down_write(&crypto_alg_sem); | |
271 | ||
272 | crypto_remove_spawns(alg, &list, NULL); | |
273 | ||
274 | if (priority) | |
275 | alg->cra_priority = nla_get_u32(priority); | |
276 | ||
277 | up_write(&crypto_alg_sem); | |
278 | ||
279 | crypto_remove_final(&list); | |
280 | ||
281 | return 0; | |
282 | } | |
283 | ||
284 | static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh, | |
285 | struct nlattr **attrs) | |
286 | { | |
287 | struct crypto_alg *alg; | |
288 | struct crypto_user_alg *p = nlmsg_data(nlh); | |
289 | ||
290 | alg = crypto_alg_match(p, 1); | |
291 | if (!alg) | |
292 | return -ENOENT; | |
293 | ||
294 | /* We can not unregister core algorithms such as aes-generic. | |
295 | * We would loose the reference in the crypto_alg_list to this algorithm | |
296 | * if we try to unregister. Unregistering such an algorithm without | |
297 | * removing the module is not possible, so we restrict to crypto | |
298 | * instances that are build from templates. */ | |
299 | if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE)) | |
300 | return -EINVAL; | |
301 | ||
302 | if (atomic_read(&alg->cra_refcnt) != 1) | |
303 | return -EBUSY; | |
304 | ||
ce3fd840 | 305 | return crypto_unregister_instance(alg); |
a38f7907 SK |
306 | } |
307 | ||
1e122994 SK |
308 | static struct crypto_alg *crypto_user_skcipher_alg(const char *name, u32 type, |
309 | u32 mask) | |
310 | { | |
311 | int err; | |
312 | struct crypto_alg *alg; | |
313 | ||
314 | type = crypto_skcipher_type(type); | |
315 | mask = crypto_skcipher_mask(mask); | |
316 | ||
317 | for (;;) { | |
318 | alg = crypto_lookup_skcipher(name, type, mask); | |
319 | if (!IS_ERR(alg)) | |
320 | return alg; | |
321 | ||
322 | err = PTR_ERR(alg); | |
323 | if (err != -EAGAIN) | |
324 | break; | |
325 | if (signal_pending(current)) { | |
326 | err = -EINTR; | |
327 | break; | |
328 | } | |
329 | } | |
330 | ||
331 | return ERR_PTR(err); | |
332 | } | |
333 | ||
334 | static struct crypto_alg *crypto_user_aead_alg(const char *name, u32 type, | |
335 | u32 mask) | |
336 | { | |
337 | int err; | |
338 | struct crypto_alg *alg; | |
339 | ||
340 | type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV); | |
341 | type |= CRYPTO_ALG_TYPE_AEAD; | |
342 | mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV); | |
343 | mask |= CRYPTO_ALG_TYPE_MASK; | |
344 | ||
345 | for (;;) { | |
346 | alg = crypto_lookup_aead(name, type, mask); | |
347 | if (!IS_ERR(alg)) | |
348 | return alg; | |
349 | ||
350 | err = PTR_ERR(alg); | |
351 | if (err != -EAGAIN) | |
352 | break; | |
353 | if (signal_pending(current)) { | |
354 | err = -EINTR; | |
355 | break; | |
356 | } | |
357 | } | |
358 | ||
359 | return ERR_PTR(err); | |
360 | } | |
361 | ||
a38f7907 SK |
362 | static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh, |
363 | struct nlattr **attrs) | |
364 | { | |
0cfdec7a | 365 | int exact = 0; |
a38f7907 SK |
366 | const char *name; |
367 | struct crypto_alg *alg; | |
368 | struct crypto_user_alg *p = nlmsg_data(nlh); | |
369 | struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL]; | |
370 | ||
371 | if (strlen(p->cru_driver_name)) | |
372 | exact = 1; | |
373 | ||
374 | if (priority && !exact) | |
375 | return -EINVAL; | |
376 | ||
377 | alg = crypto_alg_match(p, exact); | |
378 | if (alg) | |
379 | return -EEXIST; | |
380 | ||
381 | if (strlen(p->cru_driver_name)) | |
382 | name = p->cru_driver_name; | |
383 | else | |
384 | name = p->cru_name; | |
385 | ||
1e122994 SK |
386 | switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) { |
387 | case CRYPTO_ALG_TYPE_AEAD: | |
388 | alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask); | |
389 | break; | |
390 | case CRYPTO_ALG_TYPE_GIVCIPHER: | |
391 | case CRYPTO_ALG_TYPE_BLKCIPHER: | |
392 | case CRYPTO_ALG_TYPE_ABLKCIPHER: | |
393 | alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask); | |
394 | break; | |
395 | default: | |
396 | alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask); | |
397 | } | |
398 | ||
a38f7907 SK |
399 | if (IS_ERR(alg)) |
400 | return PTR_ERR(alg); | |
401 | ||
402 | down_write(&crypto_alg_sem); | |
403 | ||
404 | if (priority) | |
405 | alg->cra_priority = nla_get_u32(priority); | |
406 | ||
407 | up_write(&crypto_alg_sem); | |
408 | ||
409 | crypto_mod_put(alg); | |
410 | ||
411 | return 0; | |
412 | } | |
413 | ||
414 | #define MSGSIZE(type) sizeof(struct type) | |
415 | ||
416 | static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = { | |
417 | [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | |
418 | [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | |
419 | [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | |
420 | [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | |
421 | }; | |
422 | ||
423 | static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = { | |
424 | [CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32}, | |
425 | }; | |
426 | ||
427 | #undef MSGSIZE | |
428 | ||
429 | static struct crypto_link { | |
430 | int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **); | |
431 | int (*dump)(struct sk_buff *, struct netlink_callback *); | |
432 | int (*done)(struct netlink_callback *); | |
433 | } crypto_dispatch[CRYPTO_NR_MSGTYPES] = { | |
434 | [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg}, | |
435 | [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg}, | |
436 | [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg}, | |
437 | [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report, | |
438 | .dump = crypto_dump_report, | |
439 | .done = crypto_dump_report_done}, | |
440 | }; | |
441 | ||
442 | static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) | |
443 | { | |
444 | struct nlattr *attrs[CRYPTOCFGA_MAX+1]; | |
445 | struct crypto_link *link; | |
446 | int type, err; | |
447 | ||
448 | type = nlh->nlmsg_type; | |
449 | if (type > CRYPTO_MSG_MAX) | |
450 | return -EINVAL; | |
451 | ||
452 | type -= CRYPTO_MSG_BASE; | |
453 | link = &crypto_dispatch[type]; | |
454 | ||
c49c41a4 | 455 | if (!capable(CAP_NET_ADMIN)) |
a38f7907 SK |
456 | return -EPERM; |
457 | ||
458 | if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) && | |
459 | (nlh->nlmsg_flags & NLM_F_DUMP))) { | |
5219a534 SK |
460 | struct crypto_alg *alg; |
461 | u16 dump_alloc = 0; | |
462 | ||
a38f7907 SK |
463 | if (link->dump == NULL) |
464 | return -EINVAL; | |
5219a534 SK |
465 | |
466 | list_for_each_entry(alg, &crypto_alg_list, cra_list) | |
467 | dump_alloc += CRYPTO_REPORT_MAXSIZE; | |
468 | ||
80d326fa PNA |
469 | { |
470 | struct netlink_dump_control c = { | |
471 | .dump = link->dump, | |
472 | .done = link->done, | |
5219a534 | 473 | .min_dump_alloc = dump_alloc, |
80d326fa PNA |
474 | }; |
475 | return netlink_dump_start(crypto_nlsk, skb, nlh, &c); | |
476 | } | |
a38f7907 SK |
477 | } |
478 | ||
479 | err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX, | |
480 | crypto_policy); | |
481 | if (err < 0) | |
482 | return err; | |
483 | ||
484 | if (link->doit == NULL) | |
485 | return -EINVAL; | |
486 | ||
487 | return link->doit(skb, nlh, attrs); | |
488 | } | |
489 | ||
490 | static void crypto_netlink_rcv(struct sk_buff *skb) | |
491 | { | |
492 | mutex_lock(&crypto_cfg_mutex); | |
493 | netlink_rcv_skb(skb, &crypto_user_rcv_msg); | |
494 | mutex_unlock(&crypto_cfg_mutex); | |
495 | } | |
496 | ||
497 | static int __init crypto_user_init(void) | |
498 | { | |
a31f2d17 PNA |
499 | struct netlink_kernel_cfg cfg = { |
500 | .input = crypto_netlink_rcv, | |
501 | }; | |
502 | ||
a38f7907 | 503 | crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, |
a31f2d17 | 504 | THIS_MODULE, &cfg); |
a38f7907 SK |
505 | if (!crypto_nlsk) |
506 | return -ENOMEM; | |
507 | ||
508 | return 0; | |
509 | } | |
510 | ||
511 | static void __exit crypto_user_exit(void) | |
512 | { | |
513 | netlink_kernel_release(crypto_nlsk); | |
514 | } | |
515 | ||
516 | module_init(crypto_user_init); | |
517 | module_exit(crypto_user_exit); | |
518 | MODULE_LICENSE("GPL"); | |
519 | MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>"); | |
520 | MODULE_DESCRIPTION("Crypto userspace configuration API"); |