1 /*
2  * NetLabel CIPSO/IPv4 Support
3  *
4  * This file defines the CIPSO/IPv4 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 <linux/audit.h>
36 #include <net/sock.h>
37 #include <net/netlink.h>
38 #include <net/genetlink.h>
39 #include <net/netlabel.h>
40 #include <net/cipso_ipv4.h>
41 #include <asm/atomic.h>
42 
43 #include "netlabel_user.h"
44 #include "netlabel_cipso_v4.h"
45 #include "netlabel_mgmt.h"
46 #include "netlabel_domainhash.h"
47 
48 /* Argument struct for cipso_v4_doi_walk() */
49 struct netlbl_cipsov4_doiwalk_arg {
50 	struct netlink_callback *nl_cb;
51 	struct sk_buff *skb;
52 	u32 seq;
53 };
54 
55 /* Argument struct for netlbl_domhsh_walk() */
56 struct netlbl_domhsh_walk_arg {
57 	struct netlbl_audit *audit_info;
58 	u32 doi;
59 };
60 
61 /* NetLabel Generic NETLINK CIPSOv4 family */
62 static struct genl_family netlbl_cipsov4_gnl_family = {
63 	.id = GENL_ID_GENERATE,
64 	.hdrsize = 0,
65 	.name = NETLBL_NLTYPE_CIPSOV4_NAME,
66 	.version = NETLBL_PROTO_VERSION,
67 	.maxattr = NLBL_CIPSOV4_A_MAX,
68 };
69 
70 /* NetLabel Netlink attribute policy */
71 static const struct nla_policy netlbl_cipsov4_genl_policy[NLBL_CIPSOV4_A_MAX + 1] = {
72 	[NLBL_CIPSOV4_A_DOI] = { .type = NLA_U32 },
73 	[NLBL_CIPSOV4_A_MTYPE] = { .type = NLA_U32 },
74 	[NLBL_CIPSOV4_A_TAG] = { .type = NLA_U8 },
75 	[NLBL_CIPSOV4_A_TAGLST] = { .type = NLA_NESTED },
76 	[NLBL_CIPSOV4_A_MLSLVLLOC] = { .type = NLA_U32 },
77 	[NLBL_CIPSOV4_A_MLSLVLREM] = { .type = NLA_U32 },
78 	[NLBL_CIPSOV4_A_MLSLVL] = { .type = NLA_NESTED },
79 	[NLBL_CIPSOV4_A_MLSLVLLST] = { .type = NLA_NESTED },
80 	[NLBL_CIPSOV4_A_MLSCATLOC] = { .type = NLA_U32 },
81 	[NLBL_CIPSOV4_A_MLSCATREM] = { .type = NLA_U32 },
82 	[NLBL_CIPSOV4_A_MLSCAT] = { .type = NLA_NESTED },
83 	[NLBL_CIPSOV4_A_MLSCATLST] = { .type = NLA_NESTED },
84 };
85 
86 /*
87  * Helper Functions
88  */
89 
90 /**
91  * netlbl_cipsov4_add_common - Parse the common sections of a ADD message
92  * @info: the Generic NETLINK info block
93  * @doi_def: the CIPSO V4 DOI definition
94  *
95  * Description:
96  * Parse the common sections of a ADD message and fill in the related values
97  * in @doi_def.  Returns zero on success, negative values on failure.
98  *
99  */
100 static int netlbl_cipsov4_add_common(struct genl_info *info,
101 				     struct cipso_v4_doi *doi_def)
102 {
103 	struct nlattr *nla;
104 	int nla_rem;
105 	u32 iter = 0;
106 
107 	doi_def->doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
108 
109 	if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_TAGLST],
110 				NLBL_CIPSOV4_A_MAX,
111 				netlbl_cipsov4_genl_policy) != 0)
112 		return -EINVAL;
113 
114 	nla_for_each_nested(nla, info->attrs[NLBL_CIPSOV4_A_TAGLST], nla_rem)
115 		if (nla_type(nla) == NLBL_CIPSOV4_A_TAG) {
116 			if (iter >= CIPSO_V4_TAG_MAXCNT)
117 				return -EINVAL;
118 			doi_def->tags[iter++] = nla_get_u8(nla);
119 		}
120 	while (iter < CIPSO_V4_TAG_MAXCNT)
121 		doi_def->tags[iter++] = CIPSO_V4_TAG_INVALID;
122 
123 	return 0;
124 }
125 
126 /*
127  * NetLabel Command Handlers
128  */
129 
130 /**
131  * netlbl_cipsov4_add_std - Adds a CIPSO V4 DOI definition
132  * @info: the Generic NETLINK info block
133  *
134  * Description:
135  * Create a new CIPSO_V4_MAP_TRANS DOI definition based on the given ADD
136  * message and add it to the CIPSO V4 engine.  Return zero on success and
137  * non-zero on error.
138  *
139  */
140 static int netlbl_cipsov4_add_std(struct genl_info *info)
141 {
142 	int ret_val = -EINVAL;
143 	struct cipso_v4_doi *doi_def = NULL;
144 	struct nlattr *nla_a;
145 	struct nlattr *nla_b;
146 	int nla_a_rem;
147 	int nla_b_rem;
148 	u32 iter;
149 
150 	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
151 	    !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST])
152 		return -EINVAL;
153 
154 	if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
155 				NLBL_CIPSOV4_A_MAX,
156 				netlbl_cipsov4_genl_policy) != 0)
157 		return -EINVAL;
158 
159 	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
160 	if (doi_def == NULL)
161 		return -ENOMEM;
162 	doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL);
163 	if (doi_def->map.std == NULL) {
164 		ret_val = -ENOMEM;
165 		goto add_std_failure;
166 	}
167 	doi_def->type = CIPSO_V4_MAP_TRANS;
168 
169 	ret_val = netlbl_cipsov4_add_common(info, doi_def);
170 	if (ret_val != 0)
171 		goto add_std_failure;
172 	ret_val = -EINVAL;
173 
174 	nla_for_each_nested(nla_a,
175 			    info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
176 			    nla_a_rem)
177 		if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSLVL) {
178 			if (nla_validate_nested(nla_a,
179 					    NLBL_CIPSOV4_A_MAX,
180 					    netlbl_cipsov4_genl_policy) != 0)
181 					goto add_std_failure;
182 			nla_for_each_nested(nla_b, nla_a, nla_b_rem)
183 				switch (nla_type(nla_b)) {
184 				case NLBL_CIPSOV4_A_MLSLVLLOC:
185 					if (nla_get_u32(nla_b) >
186 					    CIPSO_V4_MAX_LOC_LVLS)
187 						goto add_std_failure;
188 					if (nla_get_u32(nla_b) >=
189 					    doi_def->map.std->lvl.local_size)
190 					     doi_def->map.std->lvl.local_size =
191 						     nla_get_u32(nla_b) + 1;
192 					break;
193 				case NLBL_CIPSOV4_A_MLSLVLREM:
194 					if (nla_get_u32(nla_b) >
195 					    CIPSO_V4_MAX_REM_LVLS)
196 						goto add_std_failure;
197 					if (nla_get_u32(nla_b) >=
198 					    doi_def->map.std->lvl.cipso_size)
199 					     doi_def->map.std->lvl.cipso_size =
200 						     nla_get_u32(nla_b) + 1;
201 					break;
202 				}
203 		}
204 	doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size,
205 					      sizeof(u32),
206 					      GFP_KERNEL);
207 	if (doi_def->map.std->lvl.local == NULL) {
208 		ret_val = -ENOMEM;
209 		goto add_std_failure;
210 	}
211 	doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size,
212 					      sizeof(u32),
213 					      GFP_KERNEL);
214 	if (doi_def->map.std->lvl.cipso == NULL) {
215 		ret_val = -ENOMEM;
216 		goto add_std_failure;
217 	}
218 	for (iter = 0; iter < doi_def->map.std->lvl.local_size; iter++)
219 		doi_def->map.std->lvl.local[iter] = CIPSO_V4_INV_LVL;
220 	for (iter = 0; iter < doi_def->map.std->lvl.cipso_size; iter++)
221 		doi_def->map.std->lvl.cipso[iter] = CIPSO_V4_INV_LVL;
222 	nla_for_each_nested(nla_a,
223 			    info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
224 			    nla_a_rem)
225 		if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSLVL) {
226 			struct nlattr *lvl_loc;
227 			struct nlattr *lvl_rem;
228 
229 			lvl_loc = nla_find_nested(nla_a,
230 						  NLBL_CIPSOV4_A_MLSLVLLOC);
231 			lvl_rem = nla_find_nested(nla_a,
232 						  NLBL_CIPSOV4_A_MLSLVLREM);
233 			if (lvl_loc == NULL || lvl_rem == NULL)
234 				goto add_std_failure;
235 			doi_def->map.std->lvl.local[nla_get_u32(lvl_loc)] =
236 				nla_get_u32(lvl_rem);
237 			doi_def->map.std->lvl.cipso[nla_get_u32(lvl_rem)] =
238 				nla_get_u32(lvl_loc);
239 		}
240 
241 	if (info->attrs[NLBL_CIPSOV4_A_MLSCATLST]) {
242 		if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
243 					NLBL_CIPSOV4_A_MAX,
244 					netlbl_cipsov4_genl_policy) != 0)
245 			goto add_std_failure;
246 
247 		nla_for_each_nested(nla_a,
248 				    info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
249 				    nla_a_rem)
250 			if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSCAT) {
251 				if (nla_validate_nested(nla_a,
252 					      NLBL_CIPSOV4_A_MAX,
253 					      netlbl_cipsov4_genl_policy) != 0)
254 					goto add_std_failure;
255 				nla_for_each_nested(nla_b, nla_a, nla_b_rem)
256 					switch (nla_type(nla_b)) {
257 					case NLBL_CIPSOV4_A_MLSCATLOC:
258 						if (nla_get_u32(nla_b) >
259 						    CIPSO_V4_MAX_LOC_CATS)
260 							goto add_std_failure;
261 						if (nla_get_u32(nla_b) >=
262 					      doi_def->map.std->cat.local_size)
263 					     doi_def->map.std->cat.local_size =
264 						     nla_get_u32(nla_b) + 1;
265 						break;
266 					case NLBL_CIPSOV4_A_MLSCATREM:
267 						if (nla_get_u32(nla_b) >
268 						    CIPSO_V4_MAX_REM_CATS)
269 							goto add_std_failure;
270 						if (nla_get_u32(nla_b) >=
271 					      doi_def->map.std->cat.cipso_size)
272 					     doi_def->map.std->cat.cipso_size =
273 						     nla_get_u32(nla_b) + 1;
274 						break;
275 					}
276 			}
277 		doi_def->map.std->cat.local = kcalloc(
278 					      doi_def->map.std->cat.local_size,
279 					      sizeof(u32),
280 					      GFP_KERNEL);
281 		if (doi_def->map.std->cat.local == NULL) {
282 			ret_val = -ENOMEM;
283 			goto add_std_failure;
284 		}
285 		doi_def->map.std->cat.cipso = kcalloc(
286 					      doi_def->map.std->cat.cipso_size,
287 					      sizeof(u32),
288 					      GFP_KERNEL);
289 		if (doi_def->map.std->cat.cipso == NULL) {
290 			ret_val = -ENOMEM;
291 			goto add_std_failure;
292 		}
293 		for (iter = 0; iter < doi_def->map.std->cat.local_size; iter++)
294 			doi_def->map.std->cat.local[iter] = CIPSO_V4_INV_CAT;
295 		for (iter = 0; iter < doi_def->map.std->cat.cipso_size; iter++)
296 			doi_def->map.std->cat.cipso[iter] = CIPSO_V4_INV_CAT;
297 		nla_for_each_nested(nla_a,
298 				    info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
299 				    nla_a_rem)
300 			if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSCAT) {
301 				struct nlattr *cat_loc;
302 				struct nlattr *cat_rem;
303 
304 				cat_loc = nla_find_nested(nla_a,
305 						     NLBL_CIPSOV4_A_MLSCATLOC);
306 				cat_rem = nla_find_nested(nla_a,
307 						     NLBL_CIPSOV4_A_MLSCATREM);
308 				if (cat_loc == NULL || cat_rem == NULL)
309 					goto add_std_failure;
310 				doi_def->map.std->cat.local[
311 							nla_get_u32(cat_loc)] =
312 					nla_get_u32(cat_rem);
313 				doi_def->map.std->cat.cipso[
314 							nla_get_u32(cat_rem)] =
315 					nla_get_u32(cat_loc);
316 			}
317 	}
318 
319 	ret_val = cipso_v4_doi_add(doi_def);
320 	if (ret_val != 0)
321 		goto add_std_failure;
322 	return 0;
323 
324 add_std_failure:
325 	if (doi_def)
326 		cipso_v4_doi_free(doi_def);
327 	return ret_val;
328 }
329 
330 /**
331  * netlbl_cipsov4_add_pass - Adds a CIPSO V4 DOI definition
332  * @info: the Generic NETLINK info block
333  *
334  * Description:
335  * Create a new CIPSO_V4_MAP_PASS DOI definition based on the given ADD message
336  * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
337  * error.
338  *
339  */
340 static int netlbl_cipsov4_add_pass(struct genl_info *info)
341 {
342 	int ret_val;
343 	struct cipso_v4_doi *doi_def = NULL;
344 
345 	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
346 		return -EINVAL;
347 
348 	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
349 	if (doi_def == NULL)
350 		return -ENOMEM;
351 	doi_def->type = CIPSO_V4_MAP_PASS;
352 
353 	ret_val = netlbl_cipsov4_add_common(info, doi_def);
354 	if (ret_val != 0)
355 		goto add_pass_failure;
356 
357 	ret_val = cipso_v4_doi_add(doi_def);
358 	if (ret_val != 0)
359 		goto add_pass_failure;
360 	return 0;
361 
362 add_pass_failure:
363 	cipso_v4_doi_free(doi_def);
364 	return ret_val;
365 }
366 
367 /**
368  * netlbl_cipsov4_add_local - Adds a CIPSO V4 DOI definition
369  * @info: the Generic NETLINK info block
370  *
371  * Description:
372  * Create a new CIPSO_V4_MAP_LOCAL DOI definition based on the given ADD
373  * message and add it to the CIPSO V4 engine.  Return zero on success and
374  * non-zero on error.
375  *
376  */
377 static int netlbl_cipsov4_add_local(struct genl_info *info)
378 {
379 	int ret_val;
380 	struct cipso_v4_doi *doi_def = NULL;
381 
382 	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
383 		return -EINVAL;
384 
385 	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
386 	if (doi_def == NULL)
387 		return -ENOMEM;
388 	doi_def->type = CIPSO_V4_MAP_LOCAL;
389 
390 	ret_val = netlbl_cipsov4_add_common(info, doi_def);
391 	if (ret_val != 0)
392 		goto add_local_failure;
393 
394 	ret_val = cipso_v4_doi_add(doi_def);
395 	if (ret_val != 0)
396 		goto add_local_failure;
397 	return 0;
398 
399 add_local_failure:
400 	cipso_v4_doi_free(doi_def);
401 	return ret_val;
402 }
403 
404 /**
405  * netlbl_cipsov4_add - Handle an ADD message
406  * @skb: the NETLINK buffer
407  * @info: the Generic NETLINK info block
408  *
409  * Description:
410  * Create a new DOI definition based on the given ADD message and add it to the
411  * CIPSO V4 engine.  Returns zero on success, negative values on failure.
412  *
413  */
414 static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)
415 
416 {
417 	int ret_val = -EINVAL;
418 	u32 type;
419 	u32 doi;
420 	const char *type_str = "(unknown)";
421 	struct audit_buffer *audit_buf;
422 	struct netlbl_audit audit_info;
423 
424 	if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
425 	    !info->attrs[NLBL_CIPSOV4_A_MTYPE])
426 		return -EINVAL;
427 
428 	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
429 	netlbl_netlink_auditinfo(skb, &audit_info);
430 
431 	type = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE]);
432 	switch (type) {
433 	case CIPSO_V4_MAP_TRANS:
434 		type_str = "trans";
435 		ret_val = netlbl_cipsov4_add_std(info);
436 		break;
437 	case CIPSO_V4_MAP_PASS:
438 		type_str = "pass";
439 		ret_val = netlbl_cipsov4_add_pass(info);
440 		break;
441 	case CIPSO_V4_MAP_LOCAL:
442 		type_str = "local";
443 		ret_val = netlbl_cipsov4_add_local(info);
444 		break;
445 	}
446 	if (ret_val == 0)
447 		atomic_inc(&netlabel_mgmt_protocount);
448 
449 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_ADD,
450 					      &audit_info);
451 	if (audit_buf != NULL) {
452 		audit_log_format(audit_buf,
453 				 " cipso_doi=%u cipso_type=%s res=%u",
454 				 doi,
455 				 type_str,
456 				 ret_val == 0 ? 1 : 0);
457 		audit_log_end(audit_buf);
458 	}
459 
460 	return ret_val;
461 }
462 
463 /**
464  * netlbl_cipsov4_list - Handle a LIST message
465  * @skb: the NETLINK buffer
466  * @info: the Generic NETLINK info block
467  *
468  * Description:
469  * Process a user generated LIST message and respond accordingly.  While the
470  * response message generated by the kernel is straightforward, determining
471  * before hand the size of the buffer to allocate is not (we have to generate
472  * the message to know the size).  In order to keep this function sane what we
473  * do is allocate a buffer of NLMSG_GOODSIZE and try to fit the response in
474  * that size, if we fail then we restart with a larger buffer and try again.
475  * We continue in this manner until we hit a limit of failed attempts then we
476  * give up and just send an error message.  Returns zero on success and
477  * negative values on error.
478  *
479  */
480 static int netlbl_cipsov4_list(struct sk_buff *skb, struct genl_info *info)
481 {
482 	int ret_val;
483 	struct sk_buff *ans_skb = NULL;
484 	u32 nlsze_mult = 1;
485 	void *data;
486 	u32 doi;
487 	struct nlattr *nla_a;
488 	struct nlattr *nla_b;
489 	struct cipso_v4_doi *doi_def;
490 	u32 iter;
491 
492 	if (!info->attrs[NLBL_CIPSOV4_A_DOI]) {
493 		ret_val = -EINVAL;
494 		goto list_failure;
495 	}
496 
497 list_start:
498 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE * nlsze_mult, GFP_KERNEL);
499 	if (ans_skb == NULL) {
500 		ret_val = -ENOMEM;
501 		goto list_failure;
502 	}
503 	data = genlmsg_put_reply(ans_skb, info, &netlbl_cipsov4_gnl_family,
504 				 0, NLBL_CIPSOV4_C_LIST);
505 	if (data == NULL) {
506 		ret_val = -ENOMEM;
507 		goto list_failure;
508 	}
509 
510 	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
511 
512 	rcu_read_lock();
513 	doi_def = cipso_v4_doi_getdef(doi);
514 	if (doi_def == NULL) {
515 		ret_val = -EINVAL;
516 		goto list_failure_lock;
517 	}
518 
519 	ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type);
520 	if (ret_val != 0)
521 		goto list_failure_lock;
522 
523 	nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_TAGLST);
524 	if (nla_a == NULL) {
525 		ret_val = -ENOMEM;
526 		goto list_failure_lock;
527 	}
528 	for (iter = 0;
529 	     iter < CIPSO_V4_TAG_MAXCNT &&
530 	       doi_def->tags[iter] != CIPSO_V4_TAG_INVALID;
531 	     iter++) {
532 		ret_val = nla_put_u8(ans_skb,
533 				     NLBL_CIPSOV4_A_TAG,
534 				     doi_def->tags[iter]);
535 		if (ret_val != 0)
536 			goto list_failure_lock;
537 	}
538 	nla_nest_end(ans_skb, nla_a);
539 
540 	switch (doi_def->type) {
541 	case CIPSO_V4_MAP_TRANS:
542 		nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVLLST);
543 		if (nla_a == NULL) {
544 			ret_val = -ENOMEM;
545 			goto list_failure_lock;
546 		}
547 		for (iter = 0;
548 		     iter < doi_def->map.std->lvl.local_size;
549 		     iter++) {
550 			if (doi_def->map.std->lvl.local[iter] ==
551 			    CIPSO_V4_INV_LVL)
552 				continue;
553 
554 			nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVL);
555 			if (nla_b == NULL) {
556 				ret_val = -ENOMEM;
557 				goto list_retry;
558 			}
559 			ret_val = nla_put_u32(ans_skb,
560 					      NLBL_CIPSOV4_A_MLSLVLLOC,
561 					      iter);
562 			if (ret_val != 0)
563 				goto list_retry;
564 			ret_val = nla_put_u32(ans_skb,
565 					    NLBL_CIPSOV4_A_MLSLVLREM,
566 					    doi_def->map.std->lvl.local[iter]);
567 			if (ret_val != 0)
568 				goto list_retry;
569 			nla_nest_end(ans_skb, nla_b);
570 		}
571 		nla_nest_end(ans_skb, nla_a);
572 
573 		nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCATLST);
574 		if (nla_a == NULL) {
575 			ret_val = -ENOMEM;
576 			goto list_retry;
577 		}
578 		for (iter = 0;
579 		     iter < doi_def->map.std->cat.local_size;
580 		     iter++) {
581 			if (doi_def->map.std->cat.local[iter] ==
582 			    CIPSO_V4_INV_CAT)
583 				continue;
584 
585 			nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCAT);
586 			if (nla_b == NULL) {
587 				ret_val = -ENOMEM;
588 				goto list_retry;
589 			}
590 			ret_val = nla_put_u32(ans_skb,
591 					      NLBL_CIPSOV4_A_MLSCATLOC,
592 					      iter);
593 			if (ret_val != 0)
594 				goto list_retry;
595 			ret_val = nla_put_u32(ans_skb,
596 					    NLBL_CIPSOV4_A_MLSCATREM,
597 					    doi_def->map.std->cat.local[iter]);
598 			if (ret_val != 0)
599 				goto list_retry;
600 			nla_nest_end(ans_skb, nla_b);
601 		}
602 		nla_nest_end(ans_skb, nla_a);
603 
604 		break;
605 	}
606 	rcu_read_unlock();
607 
608 	genlmsg_end(ans_skb, data);
609 	return genlmsg_reply(ans_skb, info);
610 
611 list_retry:
612 	/* XXX - this limit is a guesstimate */
613 	if (nlsze_mult < 4) {
614 		rcu_read_unlock();
615 		kfree_skb(ans_skb);
616 		nlsze_mult *= 2;
617 		goto list_start;
618 	}
619 list_failure_lock:
620 	rcu_read_unlock();
621 list_failure:
622 	kfree_skb(ans_skb);
623 	return ret_val;
624 }
625 
626 /**
627  * netlbl_cipsov4_listall_cb - cipso_v4_doi_walk() callback for LISTALL
628  * @doi_def: the CIPSOv4 DOI definition
629  * @arg: the netlbl_cipsov4_doiwalk_arg structure
630  *
631  * Description:
632  * This function is designed to be used as a callback to the
633  * cipso_v4_doi_walk() function for use in generating a response for a LISTALL
634  * message.  Returns the size of the message on success, negative values on
635  * failure.
636  *
637  */
638 static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg)
639 {
640 	int ret_val = -ENOMEM;
641 	struct netlbl_cipsov4_doiwalk_arg *cb_arg = arg;
642 	void *data;
643 
644 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
645 			   cb_arg->seq, &netlbl_cipsov4_gnl_family,
646 			   NLM_F_MULTI, NLBL_CIPSOV4_C_LISTALL);
647 	if (data == NULL)
648 		goto listall_cb_failure;
649 
650 	ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi);
651 	if (ret_val != 0)
652 		goto listall_cb_failure;
653 	ret_val = nla_put_u32(cb_arg->skb,
654 			      NLBL_CIPSOV4_A_MTYPE,
655 			      doi_def->type);
656 	if (ret_val != 0)
657 		goto listall_cb_failure;
658 
659 	return genlmsg_end(cb_arg->skb, data);
660 
661 listall_cb_failure:
662 	genlmsg_cancel(cb_arg->skb, data);
663 	return ret_val;
664 }
665 
666 /**
667  * netlbl_cipsov4_listall - Handle a LISTALL message
668  * @skb: the NETLINK buffer
669  * @cb: the NETLINK callback
670  *
671  * Description:
672  * Process a user generated LISTALL message and respond accordingly.  Returns
673  * zero on success and negative values on error.
674  *
675  */
676 static int netlbl_cipsov4_listall(struct sk_buff *skb,
677 				  struct netlink_callback *cb)
678 {
679 	struct netlbl_cipsov4_doiwalk_arg cb_arg;
680 	u32 doi_skip = cb->args[0];
681 
682 	cb_arg.nl_cb = cb;
683 	cb_arg.skb = skb;
684 	cb_arg.seq = cb->nlh->nlmsg_seq;
685 
686 	cipso_v4_doi_walk(&doi_skip, netlbl_cipsov4_listall_cb, &cb_arg);
687 
688 	cb->args[0] = doi_skip;
689 	return skb->len;
690 }
691 
692 /**
693  * netlbl_cipsov4_remove_cb - netlbl_cipsov4_remove() callback for REMOVE
694  * @entry: LSM domain mapping entry
695  * @arg: the netlbl_domhsh_walk_arg structure
696  *
697  * Description:
698  * This function is intended for use by netlbl_cipsov4_remove() as the callback
699  * for the netlbl_domhsh_walk() function; it removes LSM domain map entries
700  * which are associated with the CIPSO DOI specified in @arg.  Returns zero on
701  * success, negative values on failure.
702  *
703  */
704 static int netlbl_cipsov4_remove_cb(struct netlbl_dom_map *entry, void *arg)
705 {
706 	struct netlbl_domhsh_walk_arg *cb_arg = arg;
707 
708 	if (entry->type == NETLBL_NLTYPE_CIPSOV4 &&
709 	    entry->type_def.cipsov4->doi == cb_arg->doi)
710 		return netlbl_domhsh_remove_entry(entry, cb_arg->audit_info);
711 
712 	return 0;
713 }
714 
715 /**
716  * netlbl_cipsov4_remove - Handle a REMOVE message
717  * @skb: the NETLINK buffer
718  * @info: the Generic NETLINK info block
719  *
720  * Description:
721  * Process a user generated REMOVE message and respond accordingly.  Returns
722  * zero on success, negative values on failure.
723  *
724  */
725 static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
726 {
727 	int ret_val = -EINVAL;
728 	u32 doi = 0;
729 	struct netlbl_domhsh_walk_arg cb_arg;
730 	struct audit_buffer *audit_buf;
731 	struct netlbl_audit audit_info;
732 	u32 skip_bkt = 0;
733 	u32 skip_chain = 0;
734 
735 	if (!info->attrs[NLBL_CIPSOV4_A_DOI])
736 		return -EINVAL;
737 
738 	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
739 	netlbl_netlink_auditinfo(skb, &audit_info);
740 
741 	cb_arg.doi = doi;
742 	cb_arg.audit_info = &audit_info;
743 	ret_val = netlbl_domhsh_walk(&skip_bkt, &skip_chain,
744 				     netlbl_cipsov4_remove_cb, &cb_arg);
745 	if (ret_val == 0 || ret_val == -ENOENT) {
746 		ret_val = cipso_v4_doi_remove(doi, &audit_info);
747 		if (ret_val == 0)
748 			atomic_dec(&netlabel_mgmt_protocount);
749 	}
750 
751 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_DEL,
752 					      &audit_info);
753 	if (audit_buf != NULL) {
754 		audit_log_format(audit_buf,
755 				 " cipso_doi=%u res=%u",
756 				 doi,
757 				 ret_val == 0 ? 1 : 0);
758 		audit_log_end(audit_buf);
759 	}
760 
761 	return ret_val;
762 }
763 
764 /*
765  * NetLabel Generic NETLINK Command Definitions
766  */
767 
768 static struct genl_ops netlbl_cipsov4_ops[] = {
769 	{
770 	.cmd = NLBL_CIPSOV4_C_ADD,
771 	.flags = GENL_ADMIN_PERM,
772 	.policy = netlbl_cipsov4_genl_policy,
773 	.doit = netlbl_cipsov4_add,
774 	.dumpit = NULL,
775 	},
776 	{
777 	.cmd = NLBL_CIPSOV4_C_REMOVE,
778 	.flags = GENL_ADMIN_PERM,
779 	.policy = netlbl_cipsov4_genl_policy,
780 	.doit = netlbl_cipsov4_remove,
781 	.dumpit = NULL,
782 	},
783 	{
784 	.cmd = NLBL_CIPSOV4_C_LIST,
785 	.flags = 0,
786 	.policy = netlbl_cipsov4_genl_policy,
787 	.doit = netlbl_cipsov4_list,
788 	.dumpit = NULL,
789 	},
790 	{
791 	.cmd = NLBL_CIPSOV4_C_LISTALL,
792 	.flags = 0,
793 	.policy = netlbl_cipsov4_genl_policy,
794 	.doit = NULL,
795 	.dumpit = netlbl_cipsov4_listall,
796 	},
797 };
798 
799 /*
800  * NetLabel Generic NETLINK Protocol Functions
801  */
802 
803 /**
804  * netlbl_cipsov4_genl_init - Register the CIPSOv4 NetLabel component
805  *
806  * Description:
807  * Register the CIPSOv4 packet NetLabel component with the Generic NETLINK
808  * mechanism.  Returns zero on success, negative values on failure.
809  *
810  */
811 int __init netlbl_cipsov4_genl_init(void)
812 {
813 	int ret_val, i;
814 
815 	ret_val = genl_register_family(&netlbl_cipsov4_gnl_family);
816 	if (ret_val != 0)
817 		return ret_val;
818 
819 	for (i = 0; i < ARRAY_SIZE(netlbl_cipsov4_ops); i++) {
820 		ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
821 				&netlbl_cipsov4_ops[i]);
822 		if (ret_val != 0)
823 			return ret_val;
824 	}
825 
826 	return 0;
827 }
828