blob: 43665d0d0905ddddf018fe68655c1ff7685b0b9e [file] [log] [blame]
Steffen Klasserta38f7902011-09-27 07:23:50 +02001/*
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>
Steffen Klassert1e122992012-03-29 09:03:47 +020024#include <linux/sched.h>
Steffen Klasserta38f7902011-09-27 07:23:50 +020025#include <net/netlink.h>
26#include <linux/security.h>
27#include <net/net_namespace.h>
Steffen Klassert1e122992012-03-29 09:03:47 +020028#include <crypto/internal/aead.h>
29#include <crypto/internal/skcipher.h>
30
Steffen Klasserta38f7902011-09-27 07:23:50 +020031#include "internal.h"
32
Mathias Krause8fd61d32013-02-05 18:19:15 +010033#define null_terminated(x) (strnlen(x, sizeof(x)) < sizeof(x))
34
Jussi Kivilinna66ce0b02012-08-28 16:46:54 +030035static DEFINE_MUTEX(crypto_cfg_mutex);
Steffen Klasserta38f7902011-09-27 07:23:50 +020036
37/* The crypto netlink socket */
38static struct sock *crypto_nlsk;
39
40struct crypto_dump_info {
41 struct sk_buff *in_skb;
42 struct sk_buff *out_skb;
43 u32 nlmsg_seq;
44 u16 nlmsg_flags;
45};
46
47static struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact)
48{
Steffen Klasserta38f7902011-09-27 07:23:50 +020049 struct crypto_alg *q, *alg = NULL;
50
51 down_read(&crypto_alg_sem);
52
Steffen Klasserta38f7902011-09-27 07:23:50 +020053 list_for_each_entry(q, &crypto_alg_list, cra_list) {
Herbert Xue6ea64e2011-10-21 14:37:10 +020054 int match = 0;
Steffen Klasserta38f7902011-09-27 07:23:50 +020055
56 if ((q->cra_flags ^ p->cru_type) & p->cru_mask)
57 continue;
58
59 if (strlen(p->cru_driver_name))
60 match = !strcmp(q->cra_driver_name,
61 p->cru_driver_name);
62 else if (!exact)
63 match = !strcmp(q->cra_name, p->cru_name);
64
65 if (match) {
66 alg = q;
67 break;
68 }
69 }
70
71 up_read(&crypto_alg_sem);
72
73 return alg;
74}
75
Steffen Klassert07a5fa42011-09-27 07:48:01 +020076static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
77{
78 struct crypto_report_cipher rcipher;
79
Mathias Krause9a5467b2013-02-05 18:19:13 +010080 strncpy(rcipher.type, "cipher", sizeof(rcipher.type));
Steffen Klassert07a5fa42011-09-27 07:48:01 +020081
82 rcipher.blocksize = alg->cra_blocksize;
83 rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
84 rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
85
David S. Miller6662df32012-04-01 20:19:05 -040086 if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
87 sizeof(struct crypto_report_cipher), &rcipher))
88 goto nla_put_failure;
Steffen Klassert07a5fa42011-09-27 07:48:01 +020089 return 0;
90
91nla_put_failure:
92 return -EMSGSIZE;
93}
94
Steffen Klassert540b97c2011-09-27 07:48:48 +020095static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
96{
97 struct crypto_report_comp rcomp;
98
Mathias Krause9a5467b2013-02-05 18:19:13 +010099 strncpy(rcomp.type, "compression", sizeof(rcomp.type));
David S. Miller6662df32012-04-01 20:19:05 -0400100 if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
101 sizeof(struct crypto_report_comp), &rcomp))
102 goto nla_put_failure;
Steffen Klassert540b97c2011-09-27 07:48:48 +0200103 return 0;
104
105nla_put_failure:
106 return -EMSGSIZE;
107}
108
Steffen Klasserta38f7902011-09-27 07:23:50 +0200109static int crypto_report_one(struct crypto_alg *alg,
110 struct crypto_user_alg *ualg, struct sk_buff *skb)
111{
Mathias Krause9a5467b2013-02-05 18:19:13 +0100112 strncpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
113 strncpy(ualg->cru_driver_name, alg->cra_driver_name,
114 sizeof(ualg->cru_driver_name));
115 strncpy(ualg->cru_module_name, module_name(alg->cra_module),
116 sizeof(ualg->cru_module_name));
Steffen Klasserta38f7902011-09-27 07:23:50 +0200117
Mathias Krause9a5467b2013-02-05 18:19:13 +0100118 ualg->cru_type = 0;
119 ualg->cru_mask = 0;
Steffen Klasserta38f7902011-09-27 07:23:50 +0200120 ualg->cru_flags = alg->cra_flags;
121 ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);
122
David S. Miller6662df32012-04-01 20:19:05 -0400123 if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
124 goto nla_put_failure;
Steffen Klassert6c5a86f52011-09-27 07:25:05 +0200125 if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
126 struct crypto_report_larval rl;
127
Mathias Krause9a5467b2013-02-05 18:19:13 +0100128 strncpy(rl.type, "larval", sizeof(rl.type));
David S. Miller6662df32012-04-01 20:19:05 -0400129 if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL,
130 sizeof(struct crypto_report_larval), &rl))
131 goto nla_put_failure;
Steffen Klassert6c5a86f52011-09-27 07:25:05 +0200132 goto out;
133 }
134
Steffen Klassertb6aa63c2011-09-27 07:24:29 +0200135 if (alg->cra_type && alg->cra_type->report) {
136 if (alg->cra_type->report(skb, alg))
137 goto nla_put_failure;
Steffen Klassert07a5fa42011-09-27 07:48:01 +0200138
139 goto out;
140 }
141
142 switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_LARVAL)) {
143 case CRYPTO_ALG_TYPE_CIPHER:
144 if (crypto_report_cipher(skb, alg))
145 goto nla_put_failure;
146
147 break;
Steffen Klassert540b97c2011-09-27 07:48:48 +0200148 case CRYPTO_ALG_TYPE_COMPRESS:
149 if (crypto_report_comp(skb, alg))
150 goto nla_put_failure;
151
152 break;
Steffen Klassertb6aa63c2011-09-27 07:24:29 +0200153 }
154
Steffen Klassert6c5a86f52011-09-27 07:25:05 +0200155out:
Steffen Klasserta38f7902011-09-27 07:23:50 +0200156 return 0;
157
158nla_put_failure:
159 return -EMSGSIZE;
160}
161
162static int crypto_report_alg(struct crypto_alg *alg,
163 struct crypto_dump_info *info)
164{
165 struct sk_buff *in_skb = info->in_skb;
166 struct sk_buff *skb = info->out_skb;
167 struct nlmsghdr *nlh;
168 struct crypto_user_alg *ualg;
169 int err = 0;
170
Eric W. Biederman15e47302012-09-07 20:12:54 +0000171 nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
Steffen Klasserta38f7902011-09-27 07:23:50 +0200172 CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
173 if (!nlh) {
174 err = -EMSGSIZE;
175 goto out;
176 }
177
178 ualg = nlmsg_data(nlh);
179
180 err = crypto_report_one(alg, ualg, skb);
181 if (err) {
182 nlmsg_cancel(skb, nlh);
183 goto out;
184 }
185
186 nlmsg_end(skb, nlh);
187
188out:
189 return err;
190}
191
192static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
193 struct nlattr **attrs)
194{
195 struct crypto_user_alg *p = nlmsg_data(in_nlh);
196 struct crypto_alg *alg;
197 struct sk_buff *skb;
198 struct crypto_dump_info info;
199 int err;
200
Mathias Krause8fd61d32013-02-05 18:19:15 +0100201 if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
202 return -EINVAL;
203
Mathias Krausee336ed92013-02-05 18:19:14 +0100204 if (!p->cru_driver_name[0])
Steffen Klasserta38f7902011-09-27 07:23:50 +0200205 return -EINVAL;
206
207 alg = crypto_alg_match(p, 1);
208 if (!alg)
209 return -ENOENT;
210
211 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
212 if (!skb)
213 return -ENOMEM;
214
215 info.in_skb = in_skb;
216 info.out_skb = skb;
217 info.nlmsg_seq = in_nlh->nlmsg_seq;
218 info.nlmsg_flags = 0;
219
220 err = crypto_report_alg(alg, &info);
221 if (err)
222 return err;
223
Eric W. Biederman15e47302012-09-07 20:12:54 +0000224 return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
Steffen Klasserta38f7902011-09-27 07:23:50 +0200225}
226
227static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb)
228{
229 struct crypto_alg *alg;
230 struct crypto_dump_info info;
231 int err;
232
233 if (cb->args[0])
234 goto out;
235
236 cb->args[0] = 1;
237
238 info.in_skb = cb->skb;
239 info.out_skb = skb;
240 info.nlmsg_seq = cb->nlh->nlmsg_seq;
241 info.nlmsg_flags = NLM_F_MULTI;
242
243 list_for_each_entry(alg, &crypto_alg_list, cra_list) {
244 err = crypto_report_alg(alg, &info);
245 if (err)
246 goto out_err;
247 }
248
249out:
250 return skb->len;
251out_err:
252 return err;
253}
254
255static int crypto_dump_report_done(struct netlink_callback *cb)
256{
257 return 0;
258}
259
260static int crypto_update_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
261 struct nlattr **attrs)
262{
263 struct crypto_alg *alg;
264 struct crypto_user_alg *p = nlmsg_data(nlh);
265 struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
266 LIST_HEAD(list);
267
Mathias Krause8fd61d32013-02-05 18:19:15 +0100268 if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
269 return -EINVAL;
270
Steffen Klasserta38f7902011-09-27 07:23:50 +0200271 if (priority && !strlen(p->cru_driver_name))
272 return -EINVAL;
273
274 alg = crypto_alg_match(p, 1);
275 if (!alg)
276 return -ENOENT;
277
278 down_write(&crypto_alg_sem);
279
280 crypto_remove_spawns(alg, &list, NULL);
281
282 if (priority)
283 alg->cra_priority = nla_get_u32(priority);
284
285 up_write(&crypto_alg_sem);
286
287 crypto_remove_final(&list);
288
289 return 0;
290}
291
292static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
293 struct nlattr **attrs)
294{
295 struct crypto_alg *alg;
296 struct crypto_user_alg *p = nlmsg_data(nlh);
297
Mathias Krause8fd61d32013-02-05 18:19:15 +0100298 if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
299 return -EINVAL;
300
Steffen Klasserta38f7902011-09-27 07:23:50 +0200301 alg = crypto_alg_match(p, 1);
302 if (!alg)
303 return -ENOENT;
304
305 /* We can not unregister core algorithms such as aes-generic.
306 * We would loose the reference in the crypto_alg_list to this algorithm
307 * if we try to unregister. Unregistering such an algorithm without
308 * removing the module is not possible, so we restrict to crypto
309 * instances that are build from templates. */
310 if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
311 return -EINVAL;
312
313 if (atomic_read(&alg->cra_refcnt) != 1)
314 return -EBUSY;
315
Steffen Klassertce3fd842011-11-08 10:09:17 +0100316 return crypto_unregister_instance(alg);
Steffen Klasserta38f7902011-09-27 07:23:50 +0200317}
318
Steffen Klassert1e122992012-03-29 09:03:47 +0200319static struct crypto_alg *crypto_user_skcipher_alg(const char *name, u32 type,
320 u32 mask)
321{
322 int err;
323 struct crypto_alg *alg;
324
325 type = crypto_skcipher_type(type);
326 mask = crypto_skcipher_mask(mask);
327
328 for (;;) {
329 alg = crypto_lookup_skcipher(name, type, mask);
330 if (!IS_ERR(alg))
331 return alg;
332
333 err = PTR_ERR(alg);
334 if (err != -EAGAIN)
335 break;
336 if (signal_pending(current)) {
337 err = -EINTR;
338 break;
339 }
340 }
341
342 return ERR_PTR(err);
343}
344
345static struct crypto_alg *crypto_user_aead_alg(const char *name, u32 type,
346 u32 mask)
347{
348 int err;
349 struct crypto_alg *alg;
350
351 type &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
352 type |= CRYPTO_ALG_TYPE_AEAD;
353 mask &= ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
354 mask |= CRYPTO_ALG_TYPE_MASK;
355
356 for (;;) {
357 alg = crypto_lookup_aead(name, type, mask);
358 if (!IS_ERR(alg))
359 return alg;
360
361 err = PTR_ERR(alg);
362 if (err != -EAGAIN)
363 break;
364 if (signal_pending(current)) {
365 err = -EINTR;
366 break;
367 }
368 }
369
370 return ERR_PTR(err);
371}
372
Steffen Klasserta38f7902011-09-27 07:23:50 +0200373static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
374 struct nlattr **attrs)
375{
Jesper Juhl0cfdec72012-01-29 23:39:22 +0100376 int exact = 0;
Steffen Klasserta38f7902011-09-27 07:23:50 +0200377 const char *name;
378 struct crypto_alg *alg;
379 struct crypto_user_alg *p = nlmsg_data(nlh);
380 struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
381
Mathias Krause8fd61d32013-02-05 18:19:15 +0100382 if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
383 return -EINVAL;
384
Steffen Klasserta38f7902011-09-27 07:23:50 +0200385 if (strlen(p->cru_driver_name))
386 exact = 1;
387
388 if (priority && !exact)
389 return -EINVAL;
390
391 alg = crypto_alg_match(p, exact);
392 if (alg)
393 return -EEXIST;
394
395 if (strlen(p->cru_driver_name))
396 name = p->cru_driver_name;
397 else
398 name = p->cru_name;
399
Steffen Klassert1e122992012-03-29 09:03:47 +0200400 switch (p->cru_type & p->cru_mask & CRYPTO_ALG_TYPE_MASK) {
401 case CRYPTO_ALG_TYPE_AEAD:
402 alg = crypto_user_aead_alg(name, p->cru_type, p->cru_mask);
403 break;
404 case CRYPTO_ALG_TYPE_GIVCIPHER:
405 case CRYPTO_ALG_TYPE_BLKCIPHER:
406 case CRYPTO_ALG_TYPE_ABLKCIPHER:
407 alg = crypto_user_skcipher_alg(name, p->cru_type, p->cru_mask);
408 break;
409 default:
410 alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
411 }
412
Steffen Klasserta38f7902011-09-27 07:23:50 +0200413 if (IS_ERR(alg))
414 return PTR_ERR(alg);
415
416 down_write(&crypto_alg_sem);
417
418 if (priority)
419 alg->cra_priority = nla_get_u32(priority);
420
421 up_write(&crypto_alg_sem);
422
423 crypto_mod_put(alg);
424
425 return 0;
426}
427
428#define MSGSIZE(type) sizeof(struct type)
429
430static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
431 [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
432 [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
433 [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
434 [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
435};
436
437static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
438 [CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32},
439};
440
441#undef MSGSIZE
442
Mathias Krausea84fb792013-02-24 14:09:12 +0100443static const struct crypto_link {
Steffen Klasserta38f7902011-09-27 07:23:50 +0200444 int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
445 int (*dump)(struct sk_buff *, struct netlink_callback *);
446 int (*done)(struct netlink_callback *);
447} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
448 [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
449 [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
450 [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
451 [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report,
452 .dump = crypto_dump_report,
453 .done = crypto_dump_report_done},
454};
455
456static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
457{
458 struct nlattr *attrs[CRYPTOCFGA_MAX+1];
Mathias Krausea84fb792013-02-24 14:09:12 +0100459 const struct crypto_link *link;
Steffen Klasserta38f7902011-09-27 07:23:50 +0200460 int type, err;
461
462 type = nlh->nlmsg_type;
463 if (type > CRYPTO_MSG_MAX)
464 return -EINVAL;
465
466 type -= CRYPTO_MSG_BASE;
467 link = &crypto_dispatch[type];
468
Eric W. Biederman90f62cf2014-04-23 14:29:27 -0700469 if (!netlink_capable(skb, CAP_NET_ADMIN))
Steffen Klasserta38f7902011-09-27 07:23:50 +0200470 return -EPERM;
471
472 if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
473 (nlh->nlmsg_flags & NLM_F_DUMP))) {
Steffen Klassert5219a532012-03-29 09:04:46 +0200474 struct crypto_alg *alg;
475 u16 dump_alloc = 0;
476
Steffen Klasserta38f7902011-09-27 07:23:50 +0200477 if (link->dump == NULL)
478 return -EINVAL;
Steffen Klassert5219a532012-03-29 09:04:46 +0200479
480 list_for_each_entry(alg, &crypto_alg_list, cra_list)
481 dump_alloc += CRYPTO_REPORT_MAXSIZE;
482
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +0000483 {
484 struct netlink_dump_control c = {
485 .dump = link->dump,
486 .done = link->done,
Steffen Klassert5219a532012-03-29 09:04:46 +0200487 .min_dump_alloc = dump_alloc,
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +0000488 };
489 return netlink_dump_start(crypto_nlsk, skb, nlh, &c);
490 }
Steffen Klasserta38f7902011-09-27 07:23:50 +0200491 }
492
493 err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
494 crypto_policy);
495 if (err < 0)
496 return err;
497
498 if (link->doit == NULL)
499 return -EINVAL;
500
501 return link->doit(skb, nlh, attrs);
502}
503
504static void crypto_netlink_rcv(struct sk_buff *skb)
505{
506 mutex_lock(&crypto_cfg_mutex);
507 netlink_rcv_skb(skb, &crypto_user_rcv_msg);
508 mutex_unlock(&crypto_cfg_mutex);
509}
510
511static int __init crypto_user_init(void)
512{
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +0000513 struct netlink_kernel_cfg cfg = {
514 .input = crypto_netlink_rcv,
515 };
516
Pablo Neira Ayuso9f00d972012-09-08 02:53:54 +0000517 crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg);
Steffen Klasserta38f7902011-09-27 07:23:50 +0200518 if (!crypto_nlsk)
519 return -ENOMEM;
520
521 return 0;
522}
523
524static void __exit crypto_user_exit(void)
525{
526 netlink_kernel_release(crypto_nlsk);
527}
528
529module_init(crypto_user_init);
530module_exit(crypto_user_exit);
531MODULE_LICENSE("GPL");
532MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
533MODULE_DESCRIPTION("Crypto userspace configuration API");