xref: /linux/net/netlabel/netlabel_mgmt.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /*
2  * NetLabel Management Support
3  *
4  * This file defines the management functions for the NetLabel system.  The
5  * NetLabel system manages static and dynamic label mappings for network
6  * protocols such as CIPSO and RIPSO.
7  *
8  * Author: Paul Moore <paul.moore@hp.com>
9  *
10  */
11 
12 /*
13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
14  *
15  * This program is free software;  you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or
18  * (at your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
23  * the GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program;  if not, write to the Free Software
27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28  *
29  */
30 
31 #include <linux/types.h>
32 #include <linux/socket.h>
33 #include <linux/string.h>
34 #include <linux/skbuff.h>
35 #include <net/sock.h>
36 #include <net/netlink.h>
37 #include <net/genetlink.h>
38 #include <net/netlabel.h>
39 #include <net/cipso_ipv4.h>
40 
41 #include "netlabel_domainhash.h"
42 #include "netlabel_user.h"
43 #include "netlabel_mgmt.h"
44 
45 /* Argument struct for netlbl_domhsh_walk() */
46 struct netlbl_domhsh_walk_arg {
47 	struct netlink_callback *nl_cb;
48 	struct sk_buff *skb;
49 	u32 seq;
50 };
51 
52 /* NetLabel Generic NETLINK CIPSOv4 family */
53 static struct genl_family netlbl_mgmt_gnl_family = {
54 	.id = GENL_ID_GENERATE,
55 	.hdrsize = 0,
56 	.name = NETLBL_NLTYPE_MGMT_NAME,
57 	.version = NETLBL_PROTO_VERSION,
58 	.maxattr = NLBL_MGMT_A_MAX,
59 };
60 
61 /* NetLabel Netlink attribute policy */
62 static struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
63 	[NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
64 	[NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
65 	[NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
66 	[NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
67 };
68 
69 /*
70  * NetLabel Command Handlers
71  */
72 
73 /**
74  * netlbl_mgmt_add - Handle an ADD message
75  * @skb: the NETLINK buffer
76  * @info: the Generic NETLINK info block
77  *
78  * Description:
79  * Process a user generated ADD message and add the domains from the message
80  * to the hash table.  See netlabel.h for a description of the message format.
81  * Returns zero on success, negative values on failure.
82  *
83  */
84 static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
85 {
86 	int ret_val = -EINVAL;
87 	struct netlbl_dom_map *entry = NULL;
88 	size_t tmp_size;
89 	u32 tmp_val;
90 	struct netlbl_audit audit_info;
91 
92 	if (!info->attrs[NLBL_MGMT_A_DOMAIN] ||
93 	    !info->attrs[NLBL_MGMT_A_PROTOCOL])
94 		goto add_failure;
95 
96 	netlbl_netlink_auditinfo(skb, &audit_info);
97 
98 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
99 	if (entry == NULL) {
100 		ret_val = -ENOMEM;
101 		goto add_failure;
102 	}
103 	tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
104 	entry->domain = kmalloc(tmp_size, GFP_KERNEL);
105 	if (entry->domain == NULL) {
106 		ret_val = -ENOMEM;
107 		goto add_failure;
108 	}
109 	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
110 	nla_strlcpy(entry->domain, info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
111 
112 	switch (entry->type) {
113 	case NETLBL_NLTYPE_UNLABELED:
114 		ret_val = netlbl_domhsh_add(entry, &audit_info);
115 		break;
116 	case NETLBL_NLTYPE_CIPSOV4:
117 		if (!info->attrs[NLBL_MGMT_A_CV4DOI])
118 			goto add_failure;
119 
120 		tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
121 		/* We should be holding a rcu_read_lock() here while we hold
122 		 * the result but since the entry will always be deleted when
123 		 * the CIPSO DOI is deleted we aren't going to keep the
124 		 * lock. */
125 		rcu_read_lock();
126 		entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
127 		if (entry->type_def.cipsov4 == NULL) {
128 			rcu_read_unlock();
129 			goto add_failure;
130 		}
131 		ret_val = netlbl_domhsh_add(entry, &audit_info);
132 		rcu_read_unlock();
133 		break;
134 	default:
135 		goto add_failure;
136 	}
137 	if (ret_val != 0)
138 		goto add_failure;
139 
140 	return 0;
141 
142 add_failure:
143 	if (entry)
144 		kfree(entry->domain);
145 	kfree(entry);
146 	return ret_val;
147 }
148 
149 /**
150  * netlbl_mgmt_remove - Handle a REMOVE message
151  * @skb: the NETLINK buffer
152  * @info: the Generic NETLINK info block
153  *
154  * Description:
155  * Process a user generated REMOVE message and remove the specified domain
156  * mappings.  Returns zero on success, negative values on failure.
157  *
158  */
159 static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
160 {
161 	char *domain;
162 	struct netlbl_audit audit_info;
163 
164 	if (!info->attrs[NLBL_MGMT_A_DOMAIN])
165 		return -EINVAL;
166 
167 	netlbl_netlink_auditinfo(skb, &audit_info);
168 
169 	domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
170 	return netlbl_domhsh_remove(domain, &audit_info);
171 }
172 
173 /**
174  * netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
175  * @entry: the domain mapping hash table entry
176  * @arg: the netlbl_domhsh_walk_arg structure
177  *
178  * Description:
179  * This function is designed to be used as a callback to the
180  * netlbl_domhsh_walk() function for use in generating a response for a LISTALL
181  * message.  Returns the size of the message on success, negative values on
182  * failure.
183  *
184  */
185 static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg)
186 {
187 	int ret_val = -ENOMEM;
188 	struct netlbl_domhsh_walk_arg *cb_arg = arg;
189 	void *data;
190 
191 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
192 			   cb_arg->seq, &netlbl_mgmt_gnl_family,
193 			   NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
194 	if (data == NULL)
195 		goto listall_cb_failure;
196 
197 	ret_val = nla_put_string(cb_arg->skb,
198 				 NLBL_MGMT_A_DOMAIN,
199 				 entry->domain);
200 	if (ret_val != 0)
201 		goto listall_cb_failure;
202 	ret_val = nla_put_u32(cb_arg->skb, NLBL_MGMT_A_PROTOCOL, entry->type);
203 	if (ret_val != 0)
204 		goto listall_cb_failure;
205 	switch (entry->type) {
206 	case NETLBL_NLTYPE_CIPSOV4:
207 		ret_val = nla_put_u32(cb_arg->skb,
208 				      NLBL_MGMT_A_CV4DOI,
209 				      entry->type_def.cipsov4->doi);
210 		if (ret_val != 0)
211 			goto listall_cb_failure;
212 		break;
213 	}
214 
215 	cb_arg->seq++;
216 	return genlmsg_end(cb_arg->skb, data);
217 
218 listall_cb_failure:
219 	genlmsg_cancel(cb_arg->skb, data);
220 	return ret_val;
221 }
222 
223 /**
224  * netlbl_mgmt_listall - Handle a LISTALL message
225  * @skb: the NETLINK buffer
226  * @cb: the NETLINK callback
227  *
228  * Description:
229  * Process a user generated LISTALL message and dumps the domain hash table in
230  * a form suitable for use in a kernel generated LISTALL message.  Returns zero
231  * on success, negative values on failure.
232  *
233  */
234 static int netlbl_mgmt_listall(struct sk_buff *skb,
235 			       struct netlink_callback *cb)
236 {
237 	struct netlbl_domhsh_walk_arg cb_arg;
238 	u32 skip_bkt = cb->args[0];
239 	u32 skip_chain = cb->args[1];
240 
241 	cb_arg.nl_cb = cb;
242 	cb_arg.skb = skb;
243 	cb_arg.seq = cb->nlh->nlmsg_seq;
244 
245 	netlbl_domhsh_walk(&skip_bkt,
246 			   &skip_chain,
247 			   netlbl_mgmt_listall_cb,
248 			   &cb_arg);
249 
250 	cb->args[0] = skip_bkt;
251 	cb->args[1] = skip_chain;
252 	return skb->len;
253 }
254 
255 /**
256  * netlbl_mgmt_adddef - Handle an ADDDEF message
257  * @skb: the NETLINK buffer
258  * @info: the Generic NETLINK info block
259  *
260  * Description:
261  * Process a user generated ADDDEF message and respond accordingly.  Returns
262  * zero on success, negative values on failure.
263  *
264  */
265 static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
266 {
267 	int ret_val = -EINVAL;
268 	struct netlbl_dom_map *entry = NULL;
269 	u32 tmp_val;
270 	struct netlbl_audit audit_info;
271 
272 	if (!info->attrs[NLBL_MGMT_A_PROTOCOL])
273 		goto adddef_failure;
274 
275 	netlbl_netlink_auditinfo(skb, &audit_info);
276 
277 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
278 	if (entry == NULL) {
279 		ret_val = -ENOMEM;
280 		goto adddef_failure;
281 	}
282 	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
283 
284 	switch (entry->type) {
285 	case NETLBL_NLTYPE_UNLABELED:
286 		ret_val = netlbl_domhsh_add_default(entry, &audit_info);
287 		break;
288 	case NETLBL_NLTYPE_CIPSOV4:
289 		if (!info->attrs[NLBL_MGMT_A_CV4DOI])
290 			goto adddef_failure;
291 
292 		tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
293 		/* We should be holding a rcu_read_lock() here while we hold
294 		 * the result but since the entry will always be deleted when
295 		 * the CIPSO DOI is deleted we aren't going to keep the
296 		 * lock. */
297 		rcu_read_lock();
298 		entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
299 		if (entry->type_def.cipsov4 == NULL) {
300 			rcu_read_unlock();
301 			goto adddef_failure;
302 		}
303 		ret_val = netlbl_domhsh_add_default(entry, &audit_info);
304 		rcu_read_unlock();
305 		break;
306 	default:
307 		goto adddef_failure;
308 	}
309 	if (ret_val != 0)
310 		goto adddef_failure;
311 
312 	return 0;
313 
314 adddef_failure:
315 	kfree(entry);
316 	return ret_val;
317 }
318 
319 /**
320  * netlbl_mgmt_removedef - Handle a REMOVEDEF message
321  * @skb: the NETLINK buffer
322  * @info: the Generic NETLINK info block
323  *
324  * Description:
325  * Process a user generated REMOVEDEF message and remove the default domain
326  * mapping.  Returns zero on success, negative values on failure.
327  *
328  */
329 static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
330 {
331 	struct netlbl_audit audit_info;
332 
333 	netlbl_netlink_auditinfo(skb, &audit_info);
334 
335 	return netlbl_domhsh_remove_default(&audit_info);
336 }
337 
338 /**
339  * netlbl_mgmt_listdef - Handle a LISTDEF message
340  * @skb: the NETLINK buffer
341  * @info: the Generic NETLINK info block
342  *
343  * Description:
344  * Process a user generated LISTDEF message and dumps the default domain
345  * mapping in a form suitable for use in a kernel generated LISTDEF message.
346  * Returns zero on success, negative values on failure.
347  *
348  */
349 static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info)
350 {
351 	int ret_val = -ENOMEM;
352 	struct sk_buff *ans_skb = NULL;
353 	void *data;
354 	struct netlbl_dom_map *entry;
355 
356 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
357 	if (ans_skb == NULL)
358 		return -ENOMEM;
359 	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
360 				 0, NLBL_MGMT_C_LISTDEF);
361 	if (data == NULL)
362 		goto listdef_failure;
363 
364 	rcu_read_lock();
365 	entry = netlbl_domhsh_getentry(NULL);
366 	if (entry == NULL) {
367 		ret_val = -ENOENT;
368 		goto listdef_failure_lock;
369 	}
370 	ret_val = nla_put_u32(ans_skb, NLBL_MGMT_A_PROTOCOL, entry->type);
371 	if (ret_val != 0)
372 		goto listdef_failure_lock;
373 	switch (entry->type) {
374 	case NETLBL_NLTYPE_CIPSOV4:
375 		ret_val = nla_put_u32(ans_skb,
376 				      NLBL_MGMT_A_CV4DOI,
377 				      entry->type_def.cipsov4->doi);
378 		if (ret_val != 0)
379 			goto listdef_failure_lock;
380 		break;
381 	}
382 	rcu_read_unlock();
383 
384 	genlmsg_end(ans_skb, data);
385 
386 	ret_val = genlmsg_reply(ans_skb, info);
387 	if (ret_val != 0)
388 		goto listdef_failure;
389 	return 0;
390 
391 listdef_failure_lock:
392 	rcu_read_unlock();
393 listdef_failure:
394 	kfree_skb(ans_skb);
395 	return ret_val;
396 }
397 
398 /**
399  * netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
400  * @skb: the skb to write to
401  * @seq: the NETLINK sequence number
402  * @cb: the NETLINK callback
403  * @protocol: the NetLabel protocol to use in the message
404  *
405  * Description:
406  * This function is to be used in conjunction with netlbl_mgmt_protocols() to
407  * answer a application's PROTOCOLS message.  Returns the size of the message
408  * on success, negative values on failure.
409  *
410  */
411 static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
412 				    struct netlink_callback *cb,
413 				    u32 protocol)
414 {
415 	int ret_val = -ENOMEM;
416 	void *data;
417 
418 	data = genlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
419 			   &netlbl_mgmt_gnl_family, NLM_F_MULTI,
420 			   NLBL_MGMT_C_PROTOCOLS);
421 	if (data == NULL)
422 		goto protocols_cb_failure;
423 
424 	ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
425 	if (ret_val != 0)
426 		goto protocols_cb_failure;
427 
428 	return genlmsg_end(skb, data);
429 
430 protocols_cb_failure:
431 	genlmsg_cancel(skb, data);
432 	return ret_val;
433 }
434 
435 /**
436  * netlbl_mgmt_protocols - Handle a PROTOCOLS message
437  * @skb: the NETLINK buffer
438  * @cb: the NETLINK callback
439  *
440  * Description:
441  * Process a user generated PROTOCOLS message and respond accordingly.
442  *
443  */
444 static int netlbl_mgmt_protocols(struct sk_buff *skb,
445 				 struct netlink_callback *cb)
446 {
447 	u32 protos_sent = cb->args[0];
448 
449 	if (protos_sent == 0) {
450 		if (netlbl_mgmt_protocols_cb(skb,
451 					     cb,
452 					     NETLBL_NLTYPE_UNLABELED) < 0)
453 			goto protocols_return;
454 		protos_sent++;
455 	}
456 	if (protos_sent == 1) {
457 		if (netlbl_mgmt_protocols_cb(skb,
458 					     cb,
459 					     NETLBL_NLTYPE_CIPSOV4) < 0)
460 			goto protocols_return;
461 		protos_sent++;
462 	}
463 
464 protocols_return:
465 	cb->args[0] = protos_sent;
466 	return skb->len;
467 }
468 
469 /**
470  * netlbl_mgmt_version - Handle a VERSION message
471  * @skb: the NETLINK buffer
472  * @info: the Generic NETLINK info block
473  *
474  * Description:
475  * Process a user generated VERSION message and respond accordingly.  Returns
476  * zero on success, negative values on failure.
477  *
478  */
479 static int netlbl_mgmt_version(struct sk_buff *skb, struct genl_info *info)
480 {
481 	int ret_val = -ENOMEM;
482 	struct sk_buff *ans_skb = NULL;
483 	void *data;
484 
485 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
486 	if (ans_skb == NULL)
487 		return -ENOMEM;
488 	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
489 				 0, NLBL_MGMT_C_VERSION);
490 	if (data == NULL)
491 		goto version_failure;
492 
493 	ret_val = nla_put_u32(ans_skb,
494 			      NLBL_MGMT_A_VERSION,
495 			      NETLBL_PROTO_VERSION);
496 	if (ret_val != 0)
497 		goto version_failure;
498 
499 	genlmsg_end(ans_skb, data);
500 
501 	ret_val = genlmsg_reply(ans_skb, info);
502 	if (ret_val != 0)
503 		goto version_failure;
504 	return 0;
505 
506 version_failure:
507 	kfree_skb(ans_skb);
508 	return ret_val;
509 }
510 
511 
512 /*
513  * NetLabel Generic NETLINK Command Definitions
514  */
515 
516 static struct genl_ops netlbl_mgmt_genl_c_add = {
517 	.cmd = NLBL_MGMT_C_ADD,
518 	.flags = GENL_ADMIN_PERM,
519 	.policy = netlbl_mgmt_genl_policy,
520 	.doit = netlbl_mgmt_add,
521 	.dumpit = NULL,
522 };
523 
524 static struct genl_ops netlbl_mgmt_genl_c_remove = {
525 	.cmd = NLBL_MGMT_C_REMOVE,
526 	.flags = GENL_ADMIN_PERM,
527 	.policy = netlbl_mgmt_genl_policy,
528 	.doit = netlbl_mgmt_remove,
529 	.dumpit = NULL,
530 };
531 
532 static struct genl_ops netlbl_mgmt_genl_c_listall = {
533 	.cmd = NLBL_MGMT_C_LISTALL,
534 	.flags = 0,
535 	.policy = netlbl_mgmt_genl_policy,
536 	.doit = NULL,
537 	.dumpit = netlbl_mgmt_listall,
538 };
539 
540 static struct genl_ops netlbl_mgmt_genl_c_adddef = {
541 	.cmd = NLBL_MGMT_C_ADDDEF,
542 	.flags = GENL_ADMIN_PERM,
543 	.policy = netlbl_mgmt_genl_policy,
544 	.doit = netlbl_mgmt_adddef,
545 	.dumpit = NULL,
546 };
547 
548 static struct genl_ops netlbl_mgmt_genl_c_removedef = {
549 	.cmd = NLBL_MGMT_C_REMOVEDEF,
550 	.flags = GENL_ADMIN_PERM,
551 	.policy = netlbl_mgmt_genl_policy,
552 	.doit = netlbl_mgmt_removedef,
553 	.dumpit = NULL,
554 };
555 
556 static struct genl_ops netlbl_mgmt_genl_c_listdef = {
557 	.cmd = NLBL_MGMT_C_LISTDEF,
558 	.flags = 0,
559 	.policy = netlbl_mgmt_genl_policy,
560 	.doit = netlbl_mgmt_listdef,
561 	.dumpit = NULL,
562 };
563 
564 static struct genl_ops netlbl_mgmt_genl_c_protocols = {
565 	.cmd = NLBL_MGMT_C_PROTOCOLS,
566 	.flags = 0,
567 	.policy = netlbl_mgmt_genl_policy,
568 	.doit = NULL,
569 	.dumpit = netlbl_mgmt_protocols,
570 };
571 
572 static struct genl_ops netlbl_mgmt_genl_c_version = {
573 	.cmd = NLBL_MGMT_C_VERSION,
574 	.flags = 0,
575 	.policy = netlbl_mgmt_genl_policy,
576 	.doit = netlbl_mgmt_version,
577 	.dumpit = NULL,
578 };
579 
580 /*
581  * NetLabel Generic NETLINK Protocol Functions
582  */
583 
584 /**
585  * netlbl_mgmt_genl_init - Register the NetLabel management component
586  *
587  * Description:
588  * Register the NetLabel management component with the Generic NETLINK
589  * mechanism.  Returns zero on success, negative values on failure.
590  *
591  */
592 int netlbl_mgmt_genl_init(void)
593 {
594 	int ret_val;
595 
596 	ret_val = genl_register_family(&netlbl_mgmt_gnl_family);
597 	if (ret_val != 0)
598 		return ret_val;
599 
600 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
601 				    &netlbl_mgmt_genl_c_add);
602 	if (ret_val != 0)
603 		return ret_val;
604 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
605 				    &netlbl_mgmt_genl_c_remove);
606 	if (ret_val != 0)
607 		return ret_val;
608 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
609 				    &netlbl_mgmt_genl_c_listall);
610 	if (ret_val != 0)
611 		return ret_val;
612 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
613 				    &netlbl_mgmt_genl_c_adddef);
614 	if (ret_val != 0)
615 		return ret_val;
616 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
617 				    &netlbl_mgmt_genl_c_removedef);
618 	if (ret_val != 0)
619 		return ret_val;
620 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
621 				    &netlbl_mgmt_genl_c_listdef);
622 	if (ret_val != 0)
623 		return ret_val;
624 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
625 				    &netlbl_mgmt_genl_c_protocols);
626 	if (ret_val != 0)
627 		return ret_val;
628 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
629 				    &netlbl_mgmt_genl_c_version);
630 	if (ret_val != 0)
631 		return ret_val;
632 
633 	return 0;
634 }
635