xref: /linux/net/netlabel/netlabel_mgmt.c (revision b1edeb102397546438ab4624489c6ccd7b410d97)
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 #include <asm/atomic.h>
41 
42 #include "netlabel_domainhash.h"
43 #include "netlabel_user.h"
44 #include "netlabel_mgmt.h"
45 
46 /* NetLabel configured protocol counter */
47 atomic_t netlabel_mgmt_protocount = ATOMIC_INIT(0);
48 
49 /* Argument struct for netlbl_domhsh_walk() */
50 struct netlbl_domhsh_walk_arg {
51 	struct netlink_callback *nl_cb;
52 	struct sk_buff *skb;
53 	u32 seq;
54 };
55 
56 /* NetLabel Generic NETLINK CIPSOv4 family */
57 static struct genl_family netlbl_mgmt_gnl_family = {
58 	.id = GENL_ID_GENERATE,
59 	.hdrsize = 0,
60 	.name = NETLBL_NLTYPE_MGMT_NAME,
61 	.version = NETLBL_PROTO_VERSION,
62 	.maxattr = NLBL_MGMT_A_MAX,
63 };
64 
65 /* NetLabel Netlink attribute policy */
66 static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
67 	[NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
68 	[NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
69 	[NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
70 	[NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
71 };
72 
73 /*
74  * NetLabel Command Handlers
75  */
76 
77 /**
78  * netlbl_mgmt_add - Handle an ADD message
79  * @skb: the NETLINK buffer
80  * @info: the Generic NETLINK info block
81  *
82  * Description:
83  * Process a user generated ADD message and add the domains from the message
84  * to the hash table.  See netlabel.h for a description of the message format.
85  * Returns zero on success, negative values on failure.
86  *
87  */
88 static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
89 {
90 	int ret_val = -EINVAL;
91 	struct netlbl_dom_map *entry = NULL;
92 	size_t tmp_size;
93 	u32 tmp_val;
94 	struct netlbl_audit audit_info;
95 
96 	if (!info->attrs[NLBL_MGMT_A_DOMAIN] ||
97 	    !info->attrs[NLBL_MGMT_A_PROTOCOL])
98 		goto add_failure;
99 
100 	netlbl_netlink_auditinfo(skb, &audit_info);
101 
102 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
103 	if (entry == NULL) {
104 		ret_val = -ENOMEM;
105 		goto add_failure;
106 	}
107 	tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
108 	entry->domain = kmalloc(tmp_size, GFP_KERNEL);
109 	if (entry->domain == NULL) {
110 		ret_val = -ENOMEM;
111 		goto add_failure;
112 	}
113 	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
114 	nla_strlcpy(entry->domain, info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
115 
116 	switch (entry->type) {
117 	case NETLBL_NLTYPE_UNLABELED:
118 		ret_val = netlbl_domhsh_add(entry, &audit_info);
119 		break;
120 	case NETLBL_NLTYPE_CIPSOV4:
121 		if (!info->attrs[NLBL_MGMT_A_CV4DOI])
122 			goto add_failure;
123 
124 		tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
125 		entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
126 		if (entry->type_def.cipsov4 == NULL)
127 			goto add_failure;
128 		ret_val = netlbl_domhsh_add(entry, &audit_info);
129 		if (ret_val != 0)
130 			cipso_v4_doi_putdef(entry->type_def.cipsov4);
131 		break;
132 	default:
133 		goto add_failure;
134 	}
135 	if (ret_val != 0)
136 		goto add_failure;
137 
138 	return 0;
139 
140 add_failure:
141 	if (entry)
142 		kfree(entry->domain);
143 	kfree(entry);
144 	return ret_val;
145 }
146 
147 /**
148  * netlbl_mgmt_remove - Handle a REMOVE message
149  * @skb: the NETLINK buffer
150  * @info: the Generic NETLINK info block
151  *
152  * Description:
153  * Process a user generated REMOVE message and remove the specified domain
154  * mappings.  Returns zero on success, negative values on failure.
155  *
156  */
157 static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
158 {
159 	char *domain;
160 	struct netlbl_audit audit_info;
161 
162 	if (!info->attrs[NLBL_MGMT_A_DOMAIN])
163 		return -EINVAL;
164 
165 	netlbl_netlink_auditinfo(skb, &audit_info);
166 
167 	domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
168 	return netlbl_domhsh_remove(domain, &audit_info);
169 }
170 
171 /**
172  * netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
173  * @entry: the domain mapping hash table entry
174  * @arg: the netlbl_domhsh_walk_arg structure
175  *
176  * Description:
177  * This function is designed to be used as a callback to the
178  * netlbl_domhsh_walk() function for use in generating a response for a LISTALL
179  * message.  Returns the size of the message on success, negative values on
180  * failure.
181  *
182  */
183 static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg)
184 {
185 	int ret_val = -ENOMEM;
186 	struct netlbl_domhsh_walk_arg *cb_arg = arg;
187 	void *data;
188 
189 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
190 			   cb_arg->seq, &netlbl_mgmt_gnl_family,
191 			   NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
192 	if (data == NULL)
193 		goto listall_cb_failure;
194 
195 	ret_val = nla_put_string(cb_arg->skb,
196 				 NLBL_MGMT_A_DOMAIN,
197 				 entry->domain);
198 	if (ret_val != 0)
199 		goto listall_cb_failure;
200 	ret_val = nla_put_u32(cb_arg->skb, NLBL_MGMT_A_PROTOCOL, entry->type);
201 	if (ret_val != 0)
202 		goto listall_cb_failure;
203 	switch (entry->type) {
204 	case NETLBL_NLTYPE_CIPSOV4:
205 		ret_val = nla_put_u32(cb_arg->skb,
206 				      NLBL_MGMT_A_CV4DOI,
207 				      entry->type_def.cipsov4->doi);
208 		if (ret_val != 0)
209 			goto listall_cb_failure;
210 		break;
211 	}
212 
213 	cb_arg->seq++;
214 	return genlmsg_end(cb_arg->skb, data);
215 
216 listall_cb_failure:
217 	genlmsg_cancel(cb_arg->skb, data);
218 	return ret_val;
219 }
220 
221 /**
222  * netlbl_mgmt_listall - Handle a LISTALL message
223  * @skb: the NETLINK buffer
224  * @cb: the NETLINK callback
225  *
226  * Description:
227  * Process a user generated LISTALL message and dumps the domain hash table in
228  * a form suitable for use in a kernel generated LISTALL message.  Returns zero
229  * on success, negative values on failure.
230  *
231  */
232 static int netlbl_mgmt_listall(struct sk_buff *skb,
233 			       struct netlink_callback *cb)
234 {
235 	struct netlbl_domhsh_walk_arg cb_arg;
236 	u32 skip_bkt = cb->args[0];
237 	u32 skip_chain = cb->args[1];
238 
239 	cb_arg.nl_cb = cb;
240 	cb_arg.skb = skb;
241 	cb_arg.seq = cb->nlh->nlmsg_seq;
242 
243 	netlbl_domhsh_walk(&skip_bkt,
244 			   &skip_chain,
245 			   netlbl_mgmt_listall_cb,
246 			   &cb_arg);
247 
248 	cb->args[0] = skip_bkt;
249 	cb->args[1] = skip_chain;
250 	return skb->len;
251 }
252 
253 /**
254  * netlbl_mgmt_adddef - Handle an ADDDEF message
255  * @skb: the NETLINK buffer
256  * @info: the Generic NETLINK info block
257  *
258  * Description:
259  * Process a user generated ADDDEF message and respond accordingly.  Returns
260  * zero on success, negative values on failure.
261  *
262  */
263 static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
264 {
265 	int ret_val = -EINVAL;
266 	struct netlbl_dom_map *entry = NULL;
267 	u32 tmp_val;
268 	struct netlbl_audit audit_info;
269 
270 	if (!info->attrs[NLBL_MGMT_A_PROTOCOL])
271 		goto adddef_failure;
272 
273 	netlbl_netlink_auditinfo(skb, &audit_info);
274 
275 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
276 	if (entry == NULL) {
277 		ret_val = -ENOMEM;
278 		goto adddef_failure;
279 	}
280 	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
281 
282 	switch (entry->type) {
283 	case NETLBL_NLTYPE_UNLABELED:
284 		ret_val = netlbl_domhsh_add_default(entry, &audit_info);
285 		break;
286 	case NETLBL_NLTYPE_CIPSOV4:
287 		if (!info->attrs[NLBL_MGMT_A_CV4DOI])
288 			goto adddef_failure;
289 
290 		tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
291 		entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
292 		if (entry->type_def.cipsov4 == NULL)
293 			goto adddef_failure;
294 		ret_val = netlbl_domhsh_add_default(entry, &audit_info);
295 		if (ret_val != 0)
296 			cipso_v4_doi_putdef(entry->type_def.cipsov4);
297 		break;
298 	default:
299 		goto adddef_failure;
300 	}
301 	if (ret_val != 0)
302 		goto adddef_failure;
303 
304 	return 0;
305 
306 adddef_failure:
307 	kfree(entry);
308 	return ret_val;
309 }
310 
311 /**
312  * netlbl_mgmt_removedef - Handle a REMOVEDEF message
313  * @skb: the NETLINK buffer
314  * @info: the Generic NETLINK info block
315  *
316  * Description:
317  * Process a user generated REMOVEDEF message and remove the default domain
318  * mapping.  Returns zero on success, negative values on failure.
319  *
320  */
321 static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
322 {
323 	struct netlbl_audit audit_info;
324 
325 	netlbl_netlink_auditinfo(skb, &audit_info);
326 
327 	return netlbl_domhsh_remove_default(&audit_info);
328 }
329 
330 /**
331  * netlbl_mgmt_listdef - Handle a LISTDEF message
332  * @skb: the NETLINK buffer
333  * @info: the Generic NETLINK info block
334  *
335  * Description:
336  * Process a user generated LISTDEF message and dumps the default domain
337  * mapping in a form suitable for use in a kernel generated LISTDEF message.
338  * Returns zero on success, negative values on failure.
339  *
340  */
341 static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info)
342 {
343 	int ret_val = -ENOMEM;
344 	struct sk_buff *ans_skb = NULL;
345 	void *data;
346 	struct netlbl_dom_map *entry;
347 
348 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
349 	if (ans_skb == NULL)
350 		return -ENOMEM;
351 	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
352 				 0, NLBL_MGMT_C_LISTDEF);
353 	if (data == NULL)
354 		goto listdef_failure;
355 
356 	rcu_read_lock();
357 	entry = netlbl_domhsh_getentry(NULL);
358 	if (entry == NULL) {
359 		ret_val = -ENOENT;
360 		goto listdef_failure_lock;
361 	}
362 	ret_val = nla_put_u32(ans_skb, NLBL_MGMT_A_PROTOCOL, entry->type);
363 	if (ret_val != 0)
364 		goto listdef_failure_lock;
365 	switch (entry->type) {
366 	case NETLBL_NLTYPE_CIPSOV4:
367 		ret_val = nla_put_u32(ans_skb,
368 				      NLBL_MGMT_A_CV4DOI,
369 				      entry->type_def.cipsov4->doi);
370 		if (ret_val != 0)
371 			goto listdef_failure_lock;
372 		break;
373 	}
374 	rcu_read_unlock();
375 
376 	genlmsg_end(ans_skb, data);
377 	return genlmsg_reply(ans_skb, info);
378 
379 listdef_failure_lock:
380 	rcu_read_unlock();
381 listdef_failure:
382 	kfree_skb(ans_skb);
383 	return ret_val;
384 }
385 
386 /**
387  * netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
388  * @skb: the skb to write to
389  * @seq: the NETLINK sequence number
390  * @cb: the NETLINK callback
391  * @protocol: the NetLabel protocol to use in the message
392  *
393  * Description:
394  * This function is to be used in conjunction with netlbl_mgmt_protocols() to
395  * answer a application's PROTOCOLS message.  Returns the size of the message
396  * on success, negative values on failure.
397  *
398  */
399 static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
400 				    struct netlink_callback *cb,
401 				    u32 protocol)
402 {
403 	int ret_val = -ENOMEM;
404 	void *data;
405 
406 	data = genlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
407 			   &netlbl_mgmt_gnl_family, NLM_F_MULTI,
408 			   NLBL_MGMT_C_PROTOCOLS);
409 	if (data == NULL)
410 		goto protocols_cb_failure;
411 
412 	ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
413 	if (ret_val != 0)
414 		goto protocols_cb_failure;
415 
416 	return genlmsg_end(skb, data);
417 
418 protocols_cb_failure:
419 	genlmsg_cancel(skb, data);
420 	return ret_val;
421 }
422 
423 /**
424  * netlbl_mgmt_protocols - Handle a PROTOCOLS message
425  * @skb: the NETLINK buffer
426  * @cb: the NETLINK callback
427  *
428  * Description:
429  * Process a user generated PROTOCOLS message and respond accordingly.
430  *
431  */
432 static int netlbl_mgmt_protocols(struct sk_buff *skb,
433 				 struct netlink_callback *cb)
434 {
435 	u32 protos_sent = cb->args[0];
436 
437 	if (protos_sent == 0) {
438 		if (netlbl_mgmt_protocols_cb(skb,
439 					     cb,
440 					     NETLBL_NLTYPE_UNLABELED) < 0)
441 			goto protocols_return;
442 		protos_sent++;
443 	}
444 	if (protos_sent == 1) {
445 		if (netlbl_mgmt_protocols_cb(skb,
446 					     cb,
447 					     NETLBL_NLTYPE_CIPSOV4) < 0)
448 			goto protocols_return;
449 		protos_sent++;
450 	}
451 
452 protocols_return:
453 	cb->args[0] = protos_sent;
454 	return skb->len;
455 }
456 
457 /**
458  * netlbl_mgmt_version - Handle a VERSION message
459  * @skb: the NETLINK buffer
460  * @info: the Generic NETLINK info block
461  *
462  * Description:
463  * Process a user generated VERSION message and respond accordingly.  Returns
464  * zero on success, negative values on failure.
465  *
466  */
467 static int netlbl_mgmt_version(struct sk_buff *skb, struct genl_info *info)
468 {
469 	int ret_val = -ENOMEM;
470 	struct sk_buff *ans_skb = NULL;
471 	void *data;
472 
473 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
474 	if (ans_skb == NULL)
475 		return -ENOMEM;
476 	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
477 				 0, NLBL_MGMT_C_VERSION);
478 	if (data == NULL)
479 		goto version_failure;
480 
481 	ret_val = nla_put_u32(ans_skb,
482 			      NLBL_MGMT_A_VERSION,
483 			      NETLBL_PROTO_VERSION);
484 	if (ret_val != 0)
485 		goto version_failure;
486 
487 	genlmsg_end(ans_skb, data);
488 	return genlmsg_reply(ans_skb, info);
489 
490 version_failure:
491 	kfree_skb(ans_skb);
492 	return ret_val;
493 }
494 
495 
496 /*
497  * NetLabel Generic NETLINK Command Definitions
498  */
499 
500 static struct genl_ops netlbl_mgmt_genl_ops[] = {
501 	{
502 	.cmd = NLBL_MGMT_C_ADD,
503 	.flags = GENL_ADMIN_PERM,
504 	.policy = netlbl_mgmt_genl_policy,
505 	.doit = netlbl_mgmt_add,
506 	.dumpit = NULL,
507 	},
508 	{
509 	.cmd = NLBL_MGMT_C_REMOVE,
510 	.flags = GENL_ADMIN_PERM,
511 	.policy = netlbl_mgmt_genl_policy,
512 	.doit = netlbl_mgmt_remove,
513 	.dumpit = NULL,
514 	},
515 	{
516 	.cmd = NLBL_MGMT_C_LISTALL,
517 	.flags = 0,
518 	.policy = netlbl_mgmt_genl_policy,
519 	.doit = NULL,
520 	.dumpit = netlbl_mgmt_listall,
521 	},
522 	{
523 	.cmd = NLBL_MGMT_C_ADDDEF,
524 	.flags = GENL_ADMIN_PERM,
525 	.policy = netlbl_mgmt_genl_policy,
526 	.doit = netlbl_mgmt_adddef,
527 	.dumpit = NULL,
528 	},
529 	{
530 	.cmd = NLBL_MGMT_C_REMOVEDEF,
531 	.flags = GENL_ADMIN_PERM,
532 	.policy = netlbl_mgmt_genl_policy,
533 	.doit = netlbl_mgmt_removedef,
534 	.dumpit = NULL,
535 	},
536 	{
537 	.cmd = NLBL_MGMT_C_LISTDEF,
538 	.flags = 0,
539 	.policy = netlbl_mgmt_genl_policy,
540 	.doit = netlbl_mgmt_listdef,
541 	.dumpit = NULL,
542 	},
543 	{
544 	.cmd = NLBL_MGMT_C_PROTOCOLS,
545 	.flags = 0,
546 	.policy = netlbl_mgmt_genl_policy,
547 	.doit = NULL,
548 	.dumpit = netlbl_mgmt_protocols,
549 	},
550 	{
551 	.cmd = NLBL_MGMT_C_VERSION,
552 	.flags = 0,
553 	.policy = netlbl_mgmt_genl_policy,
554 	.doit = netlbl_mgmt_version,
555 	.dumpit = NULL,
556 	},
557 };
558 
559 /*
560  * NetLabel Generic NETLINK Protocol Functions
561  */
562 
563 /**
564  * netlbl_mgmt_genl_init - Register the NetLabel management component
565  *
566  * Description:
567  * Register the NetLabel management component with the Generic NETLINK
568  * mechanism.  Returns zero on success, negative values on failure.
569  *
570  */
571 int __init netlbl_mgmt_genl_init(void)
572 {
573 	int ret_val, i;
574 
575 	ret_val = genl_register_family(&netlbl_mgmt_gnl_family);
576 	if (ret_val != 0)
577 		return ret_val;
578 
579 	for (i = 0; i < ARRAY_SIZE(netlbl_mgmt_genl_ops); i++) {
580 		ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
581 				&netlbl_mgmt_genl_ops[i]);
582 		if (ret_val != 0)
583 			return ret_val;
584 	}
585 
586 	return 0;
587 }
588