1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * NetLabel CIPSO/IPv4 Support
4  *
5  * This file defines the CIPSO/IPv4 functions for the NetLabel system.  The
6  * NetLabel system manages static and dynamic label mappings for network
7  * protocols such as CIPSO and RIPSO.
8  *
9  * Author: Paul Moore <paul@paul-moore.com>
10  */
11 
12 /*
13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
14  */
15 
16 #include <linux/types.h>
17 #include <linux/socket.h>
18 #include <linux/string.h>
19 #include <linux/skbuff.h>
20 #include <linux/audit.h>
21 #include <linux/slab.h>
22 #include <net/sock.h>
23 #include <net/netlink.h>
24 #include <net/genetlink.h>
25 #include <net/netlabel.h>
26 #include <net/cipso_ipv4.h>
27 #include <linux/atomic.h>
28 
29 #include "netlabel_user.h"
30 #include "netlabel_cipso_v4.h"
31 #include "netlabel_mgmt.h"
32 #include "netlabel_domainhash.h"
33 
34 /* Argument struct for cipso_v4_doi_walk() */
35 struct netlbl_cipsov4_doiwalk_arg {
36 	struct netlink_callback *nl_cb;
37 	struct sk_buff *skb;
38 	u32 seq;
39 };
40 
41 /* Argument struct for netlbl_domhsh_walk() */
42 struct netlbl_domhsh_walk_arg {
43 	struct netlbl_audit *audit_info;
44 	u32 doi;
45 };
46 
47 /* NetLabel Generic NETLINK CIPSOv4 family */
48 static struct genl_family netlbl_cipsov4_gnl_family;
49 /* NetLabel Netlink attribute policy */
50 static const struct nla_policy netlbl_cipsov4_genl_policy[NLBL_CIPSOV4_A_MAX + 1] = {
51 	[NLBL_CIPSOV4_A_DOI] = { .type = NLA_U32 },
52 	[NLBL_CIPSOV4_A_MTYPE] = { .type = NLA_U32 },
53 	[NLBL_CIPSOV4_A_TAG] = { .type = NLA_U8 },
54 	[NLBL_CIPSOV4_A_TAGLST] = { .type = NLA_NESTED },
55 	[NLBL_CIPSOV4_A_MLSLVLLOC] = { .type = NLA_U32 },
56 	[NLBL_CIPSOV4_A_MLSLVLREM] = { .type = NLA_U32 },
57 	[NLBL_CIPSOV4_A_MLSLVL] = { .type = NLA_NESTED },
58 	[NLBL_CIPSOV4_A_MLSLVLLST] = { .type = NLA_NESTED },
59 	[NLBL_CIPSOV4_A_MLSCATLOC] = { .type = NLA_U32 },
60 	[NLBL_CIPSOV4_A_MLSCATREM] = { .type = NLA_U32 },
61 	[NLBL_CIPSOV4_A_MLSCAT] = { .type = NLA_NESTED },
62 	[NLBL_CIPSOV4_A_MLSCATLST] = { .type = NLA_NESTED },
63 };
64 
65 /*
66  * Helper Functions
67  */
68 
69 /**
70  * netlbl_cipsov4_add_common - Parse the common sections of a ADD message
71  * @info: the Generic NETLINK info block
72  * @doi_def: the CIPSO V4 DOI definition
73  *
74  * Description:
75  * Parse the common sections of a ADD message and fill in the related values
76  * in @doi_def.  Returns zero on success, negative values on failure.
77  *
78  */
79 static int netlbl_cipsov4_add_common(struct genl_info *info,
80 				     struct cipso_v4_doi *doi_def)
81 {
82 	struct nlattr *nla;
83 	int nla_rem;
84 	u32 iter = 0;
85 
86 	doi_def->doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
87 
88 	if (nla_validate_nested_deprecated(info->attrs[NLBL_CIPSOV4_A_TAGLST],
89 					   NLBL_CIPSOV4_A_MAX,
90 					   netlbl_cipsov4_genl_policy,
91 					   NULL) != 0)
92 		return -EINVAL;
93 
94 	nla_for_each_nested(nla, info->attrs[NLBL_CIPSOV4_A_TAGLST], nla_rem)
95 		if (nla_type(nla) == NLBL_CIPSOV4_A_TAG) {
96 			if (iter >= CIPSO_V4_TAG_MAXCNT)
97 				return -EINVAL;
98 			doi_def->tags[iter++] = nla_get_u8(nla);
99 		}
100 	while (iter < CIPSO_V4_TAG_MAXCNT)
101 		doi_def->tags[iter++] = CIPSO_V4_TAG_INVALID;
102 
103 	return 0;
104 }
105 
106 /*
107  * NetLabel Command Handlers
108  */
109 
110 /**
111  * netlbl_cipsov4_add_std - Adds a CIPSO V4 DOI definition
112  * @info: the Generic NETLINK info block
113  * @audit_info: NetLabel audit information
114  *
115  * Description:
116  * Create a new CIPSO_V4_MAP_TRANS DOI definition based on the given ADD
117  * message and add it to the CIPSO V4 engine.  Return zero on success and
118  * non-zero on error.
119  *
120  */
121 static int netlbl_cipsov4_add_std(struct genl_info *info,
122 				  struct netlbl_audit *audit_info)
123 {
124 	int ret_val = -EINVAL;
125 	struct cipso_v4_doi *doi_def = NULL;
126 	struct nlattr *nla_a;
127 	struct nlattr *nla_b;
128 	int nla_a_rem;
129 	int nla_b_rem;
130 	u32 iter;
131 
132 	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
133 	    !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST])
134 		return -EINVAL;
135 
136 	if (nla_validate_nested_deprecated(info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
137 					   NLBL_CIPSOV4_A_MAX,
138 					   netlbl_cipsov4_genl_policy,
139 					   NULL) != 0)
140 		return -EINVAL;
141 
142 	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
143 	if (doi_def == NULL)
144 		return -ENOMEM;
145 	doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL);
146 	if (doi_def->map.std == NULL) {
147 		ret_val = -ENOMEM;
148 		goto add_std_failure;
149 	}
150 	doi_def->type = CIPSO_V4_MAP_TRANS;
151 
152 	ret_val = netlbl_cipsov4_add_common(info, doi_def);
153 	if (ret_val != 0)
154 		goto add_std_failure;
155 	ret_val = -EINVAL;
156 
157 	nla_for_each_nested(nla_a,
158 			    info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
159 			    nla_a_rem)
160 		if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSLVL) {
161 			if (nla_validate_nested_deprecated(nla_a,
162 							   NLBL_CIPSOV4_A_MAX,
163 							   netlbl_cipsov4_genl_policy,
164 							   NULL) != 0)
165 				goto add_std_failure;
166 			nla_for_each_nested(nla_b, nla_a, nla_b_rem)
167 				switch (nla_type(nla_b)) {
168 				case NLBL_CIPSOV4_A_MLSLVLLOC:
169 					if (nla_get_u32(nla_b) >
170 					    CIPSO_V4_MAX_LOC_LVLS)
171 						goto add_std_failure;
172 					if (nla_get_u32(nla_b) >=
173 					    doi_def->map.std->lvl.local_size)
174 					     doi_def->map.std->lvl.local_size =
175 						     nla_get_u32(nla_b) + 1;
176 					break;
177 				case NLBL_CIPSOV4_A_MLSLVLREM:
178 					if (nla_get_u32(nla_b) >
179 					    CIPSO_V4_MAX_REM_LVLS)
180 						goto add_std_failure;
181 					if (nla_get_u32(nla_b) >=
182 					    doi_def->map.std->lvl.cipso_size)
183 					     doi_def->map.std->lvl.cipso_size =
184 						     nla_get_u32(nla_b) + 1;
185 					break;
186 				}
187 		}
188 	doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size,
189 					      sizeof(u32),
190 					      GFP_KERNEL);
191 	if (doi_def->map.std->lvl.local == NULL) {
192 		ret_val = -ENOMEM;
193 		goto add_std_failure;
194 	}
195 	doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size,
196 					      sizeof(u32),
197 					      GFP_KERNEL);
198 	if (doi_def->map.std->lvl.cipso == NULL) {
199 		ret_val = -ENOMEM;
200 		goto add_std_failure;
201 	}
202 	for (iter = 0; iter < doi_def->map.std->lvl.local_size; iter++)
203 		doi_def->map.std->lvl.local[iter] = CIPSO_V4_INV_LVL;
204 	for (iter = 0; iter < doi_def->map.std->lvl.cipso_size; iter++)
205 		doi_def->map.std->lvl.cipso[iter] = CIPSO_V4_INV_LVL;
206 	nla_for_each_nested(nla_a,
207 			    info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
208 			    nla_a_rem)
209 		if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSLVL) {
210 			struct nlattr *lvl_loc;
211 			struct nlattr *lvl_rem;
212 
213 			lvl_loc = nla_find_nested(nla_a,
214 						  NLBL_CIPSOV4_A_MLSLVLLOC);
215 			lvl_rem = nla_find_nested(nla_a,
216 						  NLBL_CIPSOV4_A_MLSLVLREM);
217 			if (lvl_loc == NULL || lvl_rem == NULL)
218 				goto add_std_failure;
219 			doi_def->map.std->lvl.local[nla_get_u32(lvl_loc)] =
220 				nla_get_u32(lvl_rem);
221 			doi_def->map.std->lvl.cipso[nla_get_u32(lvl_rem)] =
222 				nla_get_u32(lvl_loc);
223 		}
224 
225 	if (info->attrs[NLBL_CIPSOV4_A_MLSCATLST]) {
226 		if (nla_validate_nested_deprecated(info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
227 						   NLBL_CIPSOV4_A_MAX,
228 						   netlbl_cipsov4_genl_policy,
229 						   NULL) != 0)
230 			goto add_std_failure;
231 
232 		nla_for_each_nested(nla_a,
233 				    info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
234 				    nla_a_rem)
235 			if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSCAT) {
236 				if (nla_validate_nested_deprecated(nla_a,
237 								   NLBL_CIPSOV4_A_MAX,
238 								   netlbl_cipsov4_genl_policy,
239 								   NULL) != 0)
240 					goto add_std_failure;
241 				nla_for_each_nested(nla_b, nla_a, nla_b_rem)
242 					switch (nla_type(nla_b)) {
243 					case NLBL_CIPSOV4_A_MLSCATLOC:
244 						if (nla_get_u32(nla_b) >
245 						    CIPSO_V4_MAX_LOC_CATS)
246 							goto add_std_failure;
247 						if (nla_get_u32(nla_b) >=
248 					      doi_def->map.std->cat.local_size)
249 					     doi_def->map.std->cat.local_size =
250 						     nla_get_u32(nla_b) + 1;
251 						break;
252 					case NLBL_CIPSOV4_A_MLSCATREM:
253 						if (nla_get_u32(nla_b) >
254 						    CIPSO_V4_MAX_REM_CATS)
255 							goto add_std_failure;
256 						if (nla_get_u32(nla_b) >=
257 					      doi_def->map.std->cat.cipso_size)
258 					     doi_def->map.std->cat.cipso_size =
259 						     nla_get_u32(nla_b) + 1;
260 						break;
261 					}
262 			}
263 		doi_def->map.std->cat.local = kcalloc(
264 					      doi_def->map.std->cat.local_size,
265 					      sizeof(u32),
266 					      GFP_KERNEL);
267 		if (doi_def->map.std->cat.local == NULL) {
268 			ret_val = -ENOMEM;
269 			goto add_std_failure;
270 		}
271 		doi_def->map.std->cat.cipso = kcalloc(
272 					      doi_def->map.std->cat.cipso_size,
273 					      sizeof(u32),
274 					      GFP_KERNEL);
275 		if (doi_def->map.std->cat.cipso == NULL) {
276 			ret_val = -ENOMEM;
277 			goto add_std_failure;
278 		}
279 		for (iter = 0; iter < doi_def->map.std->cat.local_size; iter++)
280 			doi_def->map.std->cat.local[iter] = CIPSO_V4_INV_CAT;
281 		for (iter = 0; iter < doi_def->map.std->cat.cipso_size; iter++)
282 			doi_def->map.std->cat.cipso[iter] = CIPSO_V4_INV_CAT;
283 		nla_for_each_nested(nla_a,
284 				    info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
285 				    nla_a_rem)
286 			if (nla_type(nla_a) == NLBL_CIPSOV4_A_MLSCAT) {
287 				struct nlattr *cat_loc;
288 				struct nlattr *cat_rem;
289 
290 				cat_loc = nla_find_nested(nla_a,
291 						     NLBL_CIPSOV4_A_MLSCATLOC);
292 				cat_rem = nla_find_nested(nla_a,
293 						     NLBL_CIPSOV4_A_MLSCATREM);
294 				if (cat_loc == NULL || cat_rem == NULL)
295 					goto add_std_failure;
296 				doi_def->map.std->cat.local[
297 							nla_get_u32(cat_loc)] =
298 					nla_get_u32(cat_rem);
299 				doi_def->map.std->cat.cipso[
300 							nla_get_u32(cat_rem)] =
301 					nla_get_u32(cat_loc);
302 			}
303 	}
304 
305 	ret_val = cipso_v4_doi_add(doi_def, audit_info);
306 	if (ret_val != 0)
307 		goto add_std_failure;
308 	return 0;
309 
310 add_std_failure:
311 	cipso_v4_doi_free(doi_def);
312 	return ret_val;
313 }
314 
315 /**
316  * netlbl_cipsov4_add_pass - Adds a CIPSO V4 DOI definition
317  * @info: the Generic NETLINK info block
318  * @audit_info: NetLabel audit information
319  *
320  * Description:
321  * Create a new CIPSO_V4_MAP_PASS DOI definition based on the given ADD message
322  * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
323  * error.
324  *
325  */
326 static int netlbl_cipsov4_add_pass(struct genl_info *info,
327 				   struct netlbl_audit *audit_info)
328 {
329 	int ret_val;
330 	struct cipso_v4_doi *doi_def = NULL;
331 
332 	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
333 		return -EINVAL;
334 
335 	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
336 	if (doi_def == NULL)
337 		return -ENOMEM;
338 	doi_def->type = CIPSO_V4_MAP_PASS;
339 
340 	ret_val = netlbl_cipsov4_add_common(info, doi_def);
341 	if (ret_val != 0)
342 		goto add_pass_failure;
343 
344 	ret_val = cipso_v4_doi_add(doi_def, audit_info);
345 	if (ret_val != 0)
346 		goto add_pass_failure;
347 	return 0;
348 
349 add_pass_failure:
350 	cipso_v4_doi_free(doi_def);
351 	return ret_val;
352 }
353 
354 /**
355  * netlbl_cipsov4_add_local - Adds a CIPSO V4 DOI definition
356  * @info: the Generic NETLINK info block
357  * @audit_info: NetLabel audit information
358  *
359  * Description:
360  * Create a new CIPSO_V4_MAP_LOCAL DOI definition based on the given ADD
361  * message and add it to the CIPSO V4 engine.  Return zero on success and
362  * non-zero on error.
363  *
364  */
365 static int netlbl_cipsov4_add_local(struct genl_info *info,
366 				    struct netlbl_audit *audit_info)
367 {
368 	int ret_val;
369 	struct cipso_v4_doi *doi_def = NULL;
370 
371 	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
372 		return -EINVAL;
373 
374 	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
375 	if (doi_def == NULL)
376 		return -ENOMEM;
377 	doi_def->type = CIPSO_V4_MAP_LOCAL;
378 
379 	ret_val = netlbl_cipsov4_add_common(info, doi_def);
380 	if (ret_val != 0)
381 		goto add_local_failure;
382 
383 	ret_val = cipso_v4_doi_add(doi_def, audit_info);
384 	if (ret_val != 0)
385 		goto add_local_failure;
386 	return 0;
387 
388 add_local_failure:
389 	cipso_v4_doi_free(doi_def);
390 	return ret_val;
391 }
392 
393 /**
394  * netlbl_cipsov4_add - Handle an ADD message
395  * @skb: the NETLINK buffer
396  * @info: the Generic NETLINK info block
397  *
398  * Description:
399  * Create a new DOI definition based on the given ADD message and add it to the
400  * CIPSO V4 engine.  Returns zero on success, negative values on failure.
401  *
402  */
403 static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)
404 
405 {
406 	int ret_val = -EINVAL;
407 	struct netlbl_audit audit_info;
408 
409 	if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
410 	    !info->attrs[NLBL_CIPSOV4_A_MTYPE])
411 		return -EINVAL;
412 
413 	netlbl_netlink_auditinfo(skb, &audit_info);
414 	switch (nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE])) {
415 	case CIPSO_V4_MAP_TRANS:
416 		ret_val = netlbl_cipsov4_add_std(info, &audit_info);
417 		break;
418 	case CIPSO_V4_MAP_PASS:
419 		ret_val = netlbl_cipsov4_add_pass(info, &audit_info);
420 		break;
421 	case CIPSO_V4_MAP_LOCAL:
422 		ret_val = netlbl_cipsov4_add_local(info, &audit_info);
423 		break;
424 	}
425 	if (ret_val == 0)
426 		atomic_inc(&netlabel_mgmt_protocount);
427 
428 	return ret_val;
429 }
430 
431 /**
432  * netlbl_cipsov4_list - Handle a LIST message
433  * @skb: the NETLINK buffer
434  * @info: the Generic NETLINK info block
435  *
436  * Description:
437  * Process a user generated LIST message and respond accordingly.  While the
438  * response message generated by the kernel is straightforward, determining
439  * before hand the size of the buffer to allocate is not (we have to generate
440  * the message to know the size).  In order to keep this function sane what we
441  * do is allocate a buffer of NLMSG_GOODSIZE and try to fit the response in
442  * that size, if we fail then we restart with a larger buffer and try again.
443  * We continue in this manner until we hit a limit of failed attempts then we
444  * give up and just send an error message.  Returns zero on success and
445  * negative values on error.
446  *
447  */
448 static int netlbl_cipsov4_list(struct sk_buff *skb, struct genl_info *info)
449 {
450 	int ret_val;
451 	struct sk_buff *ans_skb = NULL;
452 	u32 nlsze_mult = 1;
453 	void *data;
454 	u32 doi;
455 	struct nlattr *nla_a;
456 	struct nlattr *nla_b;
457 	struct cipso_v4_doi *doi_def;
458 	u32 iter;
459 
460 	if (!info->attrs[NLBL_CIPSOV4_A_DOI]) {
461 		ret_val = -EINVAL;
462 		goto list_failure;
463 	}
464 
465 list_start:
466 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE * nlsze_mult, GFP_KERNEL);
467 	if (ans_skb == NULL) {
468 		ret_val = -ENOMEM;
469 		goto list_failure;
470 	}
471 	data = genlmsg_put_reply(ans_skb, info, &netlbl_cipsov4_gnl_family,
472 				 0, NLBL_CIPSOV4_C_LIST);
473 	if (data == NULL) {
474 		ret_val = -ENOMEM;
475 		goto list_failure;
476 	}
477 
478 	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
479 
480 	rcu_read_lock();
481 	doi_def = cipso_v4_doi_getdef(doi);
482 	if (doi_def == NULL) {
483 		ret_val = -EINVAL;
484 		goto list_failure_lock;
485 	}
486 
487 	ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type);
488 	if (ret_val != 0)
489 		goto list_failure_lock;
490 
491 	nla_a = nla_nest_start_noflag(ans_skb, NLBL_CIPSOV4_A_TAGLST);
492 	if (nla_a == NULL) {
493 		ret_val = -ENOMEM;
494 		goto list_failure_lock;
495 	}
496 	for (iter = 0;
497 	     iter < CIPSO_V4_TAG_MAXCNT &&
498 	       doi_def->tags[iter] != CIPSO_V4_TAG_INVALID;
499 	     iter++) {
500 		ret_val = nla_put_u8(ans_skb,
501 				     NLBL_CIPSOV4_A_TAG,
502 				     doi_def->tags[iter]);
503 		if (ret_val != 0)
504 			goto list_failure_lock;
505 	}
506 	nla_nest_end(ans_skb, nla_a);
507 
508 	switch (doi_def->type) {
509 	case CIPSO_V4_MAP_TRANS:
510 		nla_a = nla_nest_start_noflag(ans_skb,
511 					      NLBL_CIPSOV4_A_MLSLVLLST);
512 		if (nla_a == NULL) {
513 			ret_val = -ENOMEM;
514 			goto list_failure_lock;
515 		}
516 		for (iter = 0;
517 		     iter < doi_def->map.std->lvl.local_size;
518 		     iter++) {
519 			if (doi_def->map.std->lvl.local[iter] ==
520 			    CIPSO_V4_INV_LVL)
521 				continue;
522 
523 			nla_b = nla_nest_start_noflag(ans_skb,
524 						      NLBL_CIPSOV4_A_MLSLVL);
525 			if (nla_b == NULL) {
526 				ret_val = -ENOMEM;
527 				goto list_retry;
528 			}
529 			ret_val = nla_put_u32(ans_skb,
530 					      NLBL_CIPSOV4_A_MLSLVLLOC,
531 					      iter);
532 			if (ret_val != 0)
533 				goto list_retry;
534 			ret_val = nla_put_u32(ans_skb,
535 					    NLBL_CIPSOV4_A_MLSLVLREM,
536 					    doi_def->map.std->lvl.local[iter]);
537 			if (ret_val != 0)
538 				goto list_retry;
539 			nla_nest_end(ans_skb, nla_b);
540 		}
541 		nla_nest_end(ans_skb, nla_a);
542 
543 		nla_a = nla_nest_start_noflag(ans_skb,
544 					      NLBL_CIPSOV4_A_MLSCATLST);
545 		if (nla_a == NULL) {
546 			ret_val = -ENOMEM;
547 			goto list_retry;
548 		}
549 		for (iter = 0;
550 		     iter < doi_def->map.std->cat.local_size;
551 		     iter++) {
552 			if (doi_def->map.std->cat.local[iter] ==
553 			    CIPSO_V4_INV_CAT)
554 				continue;
555 
556 			nla_b = nla_nest_start_noflag(ans_skb,
557 						      NLBL_CIPSOV4_A_MLSCAT);
558 			if (nla_b == NULL) {
559 				ret_val = -ENOMEM;
560 				goto list_retry;
561 			}
562 			ret_val = nla_put_u32(ans_skb,
563 					      NLBL_CIPSOV4_A_MLSCATLOC,
564 					      iter);
565 			if (ret_val != 0)
566 				goto list_retry;
567 			ret_val = nla_put_u32(ans_skb,
568 					    NLBL_CIPSOV4_A_MLSCATREM,
569 					    doi_def->map.std->cat.local[iter]);
570 			if (ret_val != 0)
571 				goto list_retry;
572 			nla_nest_end(ans_skb, nla_b);
573 		}
574 		nla_nest_end(ans_skb, nla_a);
575 
576 		break;
577 	}
578 	rcu_read_unlock();
579 
580 	genlmsg_end(ans_skb, data);
581 	return genlmsg_reply(ans_skb, info);
582 
583 list_retry:
584 	/* XXX - this limit is a guesstimate */
585 	if (nlsze_mult < 4) {
586 		rcu_read_unlock();
587 		kfree_skb(ans_skb);
588 		nlsze_mult *= 2;
589 		goto list_start;
590 	}
591 list_failure_lock:
592 	rcu_read_unlock();
593 list_failure:
594 	kfree_skb(ans_skb);
595 	return ret_val;
596 }
597 
598 /**
599  * netlbl_cipsov4_listall_cb - cipso_v4_doi_walk() callback for LISTALL
600  * @doi_def: the CIPSOv4 DOI definition
601  * @arg: the netlbl_cipsov4_doiwalk_arg structure
602  *
603  * Description:
604  * This function is designed to be used as a callback to the
605  * cipso_v4_doi_walk() function for use in generating a response for a LISTALL
606  * message.  Returns the size of the message on success, negative values on
607  * failure.
608  *
609  */
610 static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg)
611 {
612 	int ret_val = -ENOMEM;
613 	struct netlbl_cipsov4_doiwalk_arg *cb_arg = arg;
614 	void *data;
615 
616 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
617 			   cb_arg->seq, &netlbl_cipsov4_gnl_family,
618 			   NLM_F_MULTI, NLBL_CIPSOV4_C_LISTALL);
619 	if (data == NULL)
620 		goto listall_cb_failure;
621 
622 	ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi);
623 	if (ret_val != 0)
624 		goto listall_cb_failure;
625 	ret_val = nla_put_u32(cb_arg->skb,
626 			      NLBL_CIPSOV4_A_MTYPE,
627 			      doi_def->type);
628 	if (ret_val != 0)
629 		goto listall_cb_failure;
630 
631 	genlmsg_end(cb_arg->skb, data);
632 	return 0;
633 
634 listall_cb_failure:
635 	genlmsg_cancel(cb_arg->skb, data);
636 	return ret_val;
637 }
638 
639 /**
640  * netlbl_cipsov4_listall - Handle a LISTALL message
641  * @skb: the NETLINK buffer
642  * @cb: the NETLINK callback
643  *
644  * Description:
645  * Process a user generated LISTALL message and respond accordingly.  Returns
646  * zero on success and negative values on error.
647  *
648  */
649 static int netlbl_cipsov4_listall(struct sk_buff *skb,
650 				  struct netlink_callback *cb)
651 {
652 	struct netlbl_cipsov4_doiwalk_arg cb_arg;
653 	u32 doi_skip = cb->args[0];
654 
655 	cb_arg.nl_cb = cb;
656 	cb_arg.skb = skb;
657 	cb_arg.seq = cb->nlh->nlmsg_seq;
658 
659 	cipso_v4_doi_walk(&doi_skip, netlbl_cipsov4_listall_cb, &cb_arg);
660 
661 	cb->args[0] = doi_skip;
662 	return skb->len;
663 }
664 
665 /**
666  * netlbl_cipsov4_remove_cb - netlbl_cipsov4_remove() callback for REMOVE
667  * @entry: LSM domain mapping entry
668  * @arg: the netlbl_domhsh_walk_arg structure
669  *
670  * Description:
671  * This function is intended for use by netlbl_cipsov4_remove() as the callback
672  * for the netlbl_domhsh_walk() function; it removes LSM domain map entries
673  * which are associated with the CIPSO DOI specified in @arg.  Returns zero on
674  * success, negative values on failure.
675  *
676  */
677 static int netlbl_cipsov4_remove_cb(struct netlbl_dom_map *entry, void *arg)
678 {
679 	struct netlbl_domhsh_walk_arg *cb_arg = arg;
680 
681 	if (entry->def.type == NETLBL_NLTYPE_CIPSOV4 &&
682 	    entry->def.cipso->doi == cb_arg->doi)
683 		return netlbl_domhsh_remove_entry(entry, cb_arg->audit_info);
684 
685 	return 0;
686 }
687 
688 /**
689  * netlbl_cipsov4_remove - Handle a REMOVE message
690  * @skb: the NETLINK buffer
691  * @info: the Generic NETLINK info block
692  *
693  * Description:
694  * Process a user generated REMOVE message and respond accordingly.  Returns
695  * zero on success, negative values on failure.
696  *
697  */
698 static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
699 {
700 	int ret_val = -EINVAL;
701 	struct netlbl_domhsh_walk_arg cb_arg;
702 	struct netlbl_audit audit_info;
703 	u32 skip_bkt = 0;
704 	u32 skip_chain = 0;
705 
706 	if (!info->attrs[NLBL_CIPSOV4_A_DOI])
707 		return -EINVAL;
708 
709 	netlbl_netlink_auditinfo(skb, &audit_info);
710 	cb_arg.doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
711 	cb_arg.audit_info = &audit_info;
712 	ret_val = netlbl_domhsh_walk(&skip_bkt, &skip_chain,
713 				     netlbl_cipsov4_remove_cb, &cb_arg);
714 	if (ret_val == 0 || ret_val == -ENOENT) {
715 		ret_val = cipso_v4_doi_remove(cb_arg.doi, &audit_info);
716 		if (ret_val == 0)
717 			atomic_dec(&netlabel_mgmt_protocount);
718 	}
719 
720 	return ret_val;
721 }
722 
723 /*
724  * NetLabel Generic NETLINK Command Definitions
725  */
726 
727 static const struct genl_ops netlbl_cipsov4_ops[] = {
728 	{
729 	.cmd = NLBL_CIPSOV4_C_ADD,
730 	.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
731 	.flags = GENL_ADMIN_PERM,
732 	.doit = netlbl_cipsov4_add,
733 	.dumpit = NULL,
734 	},
735 	{
736 	.cmd = NLBL_CIPSOV4_C_REMOVE,
737 	.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
738 	.flags = GENL_ADMIN_PERM,
739 	.doit = netlbl_cipsov4_remove,
740 	.dumpit = NULL,
741 	},
742 	{
743 	.cmd = NLBL_CIPSOV4_C_LIST,
744 	.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
745 	.flags = 0,
746 	.doit = netlbl_cipsov4_list,
747 	.dumpit = NULL,
748 	},
749 	{
750 	.cmd = NLBL_CIPSOV4_C_LISTALL,
751 	.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
752 	.flags = 0,
753 	.doit = NULL,
754 	.dumpit = netlbl_cipsov4_listall,
755 	},
756 };
757 
758 static struct genl_family netlbl_cipsov4_gnl_family __ro_after_init = {
759 	.hdrsize = 0,
760 	.name = NETLBL_NLTYPE_CIPSOV4_NAME,
761 	.version = NETLBL_PROTO_VERSION,
762 	.maxattr = NLBL_CIPSOV4_A_MAX,
763 	.policy = netlbl_cipsov4_genl_policy,
764 	.module = THIS_MODULE,
765 	.ops = netlbl_cipsov4_ops,
766 	.n_ops = ARRAY_SIZE(netlbl_cipsov4_ops),
767 };
768 
769 /*
770  * NetLabel Generic NETLINK Protocol Functions
771  */
772 
773 /**
774  * netlbl_cipsov4_genl_init - Register the CIPSOv4 NetLabel component
775  *
776  * Description:
777  * Register the CIPSOv4 packet NetLabel component with the Generic NETLINK
778  * mechanism.  Returns zero on success, negative values on failure.
779  *
780  */
781 int __init netlbl_cipsov4_genl_init(void)
782 {
783 	return genl_register_family(&netlbl_cipsov4_gnl_family);
784 }
785