1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * NetLabel Kernel API
4  *
5  * This file defines the kernel API for the NetLabel system.  The NetLabel
6  * system manages static and dynamic label mappings for network protocols such
7  * 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, 2008
14  */
15 
16 #include <linux/init.h>
17 #include <linux/types.h>
18 #include <linux/slab.h>
19 #include <linux/audit.h>
20 #include <linux/in.h>
21 #include <linux/in6.h>
22 #include <net/ip.h>
23 #include <net/ipv6.h>
24 #include <net/netlabel.h>
25 #include <net/cipso_ipv4.h>
26 #include <net/calipso.h>
27 #include <asm/bug.h>
28 #include <linux/atomic.h>
29 
30 #include "netlabel_domainhash.h"
31 #include "netlabel_unlabeled.h"
32 #include "netlabel_cipso_v4.h"
33 #include "netlabel_calipso.h"
34 #include "netlabel_user.h"
35 #include "netlabel_mgmt.h"
36 #include "netlabel_addrlist.h"
37 
38 /*
39  * Configuration Functions
40  */
41 
42 /**
43  * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping
44  * @domain: the domain mapping to remove
45  * @family: address family
46  * @addr: IP address
47  * @mask: IP address mask
48  * @audit_info: NetLabel audit information
49  *
50  * Description:
51  * Removes a NetLabel/LSM domain mapping.  A @domain value of NULL causes the
52  * default domain mapping to be removed.  Returns zero on success, negative
53  * values on failure.
54  *
55  */
netlbl_cfg_map_del(const char * domain,u16 family,const void * addr,const void * mask,struct netlbl_audit * audit_info)56 int netlbl_cfg_map_del(const char *domain,
57 		       u16 family,
58 		       const void *addr,
59 		       const void *mask,
60 		       struct netlbl_audit *audit_info)
61 {
62 	if (addr == NULL && mask == NULL) {
63 		return netlbl_domhsh_remove(domain, family, audit_info);
64 	} else if (addr != NULL && mask != NULL) {
65 		switch (family) {
66 		case AF_INET:
67 			return netlbl_domhsh_remove_af4(domain, addr, mask,
68 							audit_info);
69 #if IS_ENABLED(CONFIG_IPV6)
70 		case AF_INET6:
71 			return netlbl_domhsh_remove_af6(domain, addr, mask,
72 							audit_info);
73 #endif /* IPv6 */
74 		default:
75 			return -EPFNOSUPPORT;
76 		}
77 	} else
78 		return -EINVAL;
79 }
80 
81 /**
82  * netlbl_cfg_unlbl_map_add - Add a new unlabeled mapping
83  * @domain: the domain mapping to add
84  * @family: address family
85  * @addr: IP address
86  * @mask: IP address mask
87  * @audit_info: NetLabel audit information
88  *
89  * Description:
90  * Adds a new unlabeled NetLabel/LSM domain mapping.  A @domain value of NULL
91  * causes a new default domain mapping to be added.  Returns zero on success,
92  * negative values on failure.
93  *
94  */
netlbl_cfg_unlbl_map_add(const char * domain,u16 family,const void * addr,const void * mask,struct netlbl_audit * audit_info)95 int netlbl_cfg_unlbl_map_add(const char *domain,
96 			     u16 family,
97 			     const void *addr,
98 			     const void *mask,
99 			     struct netlbl_audit *audit_info)
100 {
101 	int ret_val = -ENOMEM;
102 	struct netlbl_dom_map *entry;
103 	struct netlbl_domaddr_map *addrmap = NULL;
104 	struct netlbl_domaddr4_map *map4 = NULL;
105 	struct netlbl_domaddr6_map *map6 = NULL;
106 
107 	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
108 	if (entry == NULL)
109 		return -ENOMEM;
110 	if (domain != NULL) {
111 		entry->domain = kstrdup(domain, GFP_ATOMIC);
112 		if (entry->domain == NULL)
113 			goto cfg_unlbl_map_add_failure;
114 	}
115 	entry->family = family;
116 
117 	if (addr == NULL && mask == NULL)
118 		entry->def.type = NETLBL_NLTYPE_UNLABELED;
119 	else if (addr != NULL && mask != NULL) {
120 		addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
121 		if (addrmap == NULL)
122 			goto cfg_unlbl_map_add_failure;
123 		INIT_LIST_HEAD(&addrmap->list4);
124 		INIT_LIST_HEAD(&addrmap->list6);
125 
126 		switch (family) {
127 		case AF_INET: {
128 			const struct in_addr *addr4 = addr;
129 			const struct in_addr *mask4 = mask;
130 			map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
131 			if (map4 == NULL)
132 				goto cfg_unlbl_map_add_failure;
133 			map4->def.type = NETLBL_NLTYPE_UNLABELED;
134 			map4->list.addr = addr4->s_addr & mask4->s_addr;
135 			map4->list.mask = mask4->s_addr;
136 			map4->list.valid = 1;
137 			ret_val = netlbl_af4list_add(&map4->list,
138 						     &addrmap->list4);
139 			if (ret_val != 0)
140 				goto cfg_unlbl_map_add_failure;
141 			break;
142 			}
143 #if IS_ENABLED(CONFIG_IPV6)
144 		case AF_INET6: {
145 			const struct in6_addr *addr6 = addr;
146 			const struct in6_addr *mask6 = mask;
147 			map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
148 			if (map6 == NULL)
149 				goto cfg_unlbl_map_add_failure;
150 			map6->def.type = NETLBL_NLTYPE_UNLABELED;
151 			map6->list.addr = *addr6;
152 			map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0];
153 			map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1];
154 			map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2];
155 			map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3];
156 			map6->list.mask = *mask6;
157 			map6->list.valid = 1;
158 			ret_val = netlbl_af6list_add(&map6->list,
159 						     &addrmap->list6);
160 			if (ret_val != 0)
161 				goto cfg_unlbl_map_add_failure;
162 			break;
163 			}
164 #endif /* IPv6 */
165 		default:
166 			goto cfg_unlbl_map_add_failure;
167 		}
168 
169 		entry->def.addrsel = addrmap;
170 		entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
171 	} else {
172 		ret_val = -EINVAL;
173 		goto cfg_unlbl_map_add_failure;
174 	}
175 
176 	ret_val = netlbl_domhsh_add(entry, audit_info);
177 	if (ret_val != 0)
178 		goto cfg_unlbl_map_add_failure;
179 
180 	return 0;
181 
182 cfg_unlbl_map_add_failure:
183 	kfree(entry->domain);
184 	kfree(entry);
185 	kfree(addrmap);
186 	kfree(map4);
187 	kfree(map6);
188 	return ret_val;
189 }
190 
191 
192 /**
193  * netlbl_cfg_unlbl_static_add - Adds a new static label
194  * @net: network namespace
195  * @dev_name: interface name
196  * @addr: IP address in network byte order (struct in[6]_addr)
197  * @mask: address mask in network byte order (struct in[6]_addr)
198  * @family: address family
199  * @secid: LSM secid value for the entry
200  * @audit_info: NetLabel audit information
201  *
202  * Description:
203  * Adds a new NetLabel static label to be used when protocol provided labels
204  * are not present on incoming traffic.  If @dev_name is NULL then the default
205  * interface will be used.  Returns zero on success, negative values on failure.
206  *
207  */
netlbl_cfg_unlbl_static_add(struct net * net,const char * dev_name,const void * addr,const void * mask,u16 family,u32 secid,struct netlbl_audit * audit_info)208 int netlbl_cfg_unlbl_static_add(struct net *net,
209 				const char *dev_name,
210 				const void *addr,
211 				const void *mask,
212 				u16 family,
213 				u32 secid,
214 				struct netlbl_audit *audit_info)
215 {
216 	u32 addr_len;
217 
218 	switch (family) {
219 	case AF_INET:
220 		addr_len = sizeof(struct in_addr);
221 		break;
222 #if IS_ENABLED(CONFIG_IPV6)
223 	case AF_INET6:
224 		addr_len = sizeof(struct in6_addr);
225 		break;
226 #endif /* IPv6 */
227 	default:
228 		return -EPFNOSUPPORT;
229 	}
230 
231 	return netlbl_unlhsh_add(net,
232 				 dev_name, addr, mask, addr_len,
233 				 secid, audit_info);
234 }
235 
236 /**
237  * netlbl_cfg_unlbl_static_del - Removes an existing static label
238  * @net: network namespace
239  * @dev_name: interface name
240  * @addr: IP address in network byte order (struct in[6]_addr)
241  * @mask: address mask in network byte order (struct in[6]_addr)
242  * @family: address family
243  * @audit_info: NetLabel audit information
244  *
245  * Description:
246  * Removes an existing NetLabel static label used when protocol provided labels
247  * are not present on incoming traffic.  If @dev_name is NULL then the default
248  * interface will be used.  Returns zero on success, negative values on failure.
249  *
250  */
netlbl_cfg_unlbl_static_del(struct net * net,const char * dev_name,const void * addr,const void * mask,u16 family,struct netlbl_audit * audit_info)251 int netlbl_cfg_unlbl_static_del(struct net *net,
252 				const char *dev_name,
253 				const void *addr,
254 				const void *mask,
255 				u16 family,
256 				struct netlbl_audit *audit_info)
257 {
258 	u32 addr_len;
259 
260 	switch (family) {
261 	case AF_INET:
262 		addr_len = sizeof(struct in_addr);
263 		break;
264 #if IS_ENABLED(CONFIG_IPV6)
265 	case AF_INET6:
266 		addr_len = sizeof(struct in6_addr);
267 		break;
268 #endif /* IPv6 */
269 	default:
270 		return -EPFNOSUPPORT;
271 	}
272 
273 	return netlbl_unlhsh_remove(net,
274 				    dev_name, addr, mask, addr_len,
275 				    audit_info);
276 }
277 
278 /**
279  * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition
280  * @doi_def: CIPSO DOI definition
281  * @audit_info: NetLabel audit information
282  *
283  * Description:
284  * Add a new CIPSO DOI definition as defined by @doi_def.  Returns zero on
285  * success and negative values on failure.
286  *
287  */
netlbl_cfg_cipsov4_add(struct cipso_v4_doi * doi_def,struct netlbl_audit * audit_info)288 int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def,
289 			   struct netlbl_audit *audit_info)
290 {
291 	return cipso_v4_doi_add(doi_def, audit_info);
292 }
293 
294 /**
295  * netlbl_cfg_cipsov4_del - Remove an existing CIPSOv4 DOI definition
296  * @doi: CIPSO DOI
297  * @audit_info: NetLabel audit information
298  *
299  * Description:
300  * Remove an existing CIPSO DOI definition matching @doi.  Returns zero on
301  * success and negative values on failure.
302  *
303  */
netlbl_cfg_cipsov4_del(u32 doi,struct netlbl_audit * audit_info)304 void netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info)
305 {
306 	cipso_v4_doi_remove(doi, audit_info);
307 }
308 
309 /**
310  * netlbl_cfg_cipsov4_map_add - Add a new CIPSOv4 DOI mapping
311  * @doi: the CIPSO DOI
312  * @domain: the domain mapping to add
313  * @addr: IP address
314  * @mask: IP address mask
315  * @audit_info: NetLabel audit information
316  *
317  * Description:
318  * Add a new NetLabel/LSM domain mapping for the given CIPSO DOI to the NetLabel
319  * subsystem.  A @domain value of NULL adds a new default domain mapping.
320  * Returns zero on success, negative values on failure.
321  *
322  */
netlbl_cfg_cipsov4_map_add(u32 doi,const char * domain,const struct in_addr * addr,const struct in_addr * mask,struct netlbl_audit * audit_info)323 int netlbl_cfg_cipsov4_map_add(u32 doi,
324 			       const char *domain,
325 			       const struct in_addr *addr,
326 			       const struct in_addr *mask,
327 			       struct netlbl_audit *audit_info)
328 {
329 	int ret_val = -ENOMEM;
330 	struct cipso_v4_doi *doi_def;
331 	struct netlbl_dom_map *entry;
332 	struct netlbl_domaddr_map *addrmap = NULL;
333 	struct netlbl_domaddr4_map *addrinfo = NULL;
334 
335 	doi_def = cipso_v4_doi_getdef(doi);
336 	if (doi_def == NULL)
337 		return -ENOENT;
338 
339 	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
340 	if (entry == NULL)
341 		goto out_entry;
342 	entry->family = AF_INET;
343 	if (domain != NULL) {
344 		entry->domain = kstrdup(domain, GFP_ATOMIC);
345 		if (entry->domain == NULL)
346 			goto out_domain;
347 	}
348 
349 	if (addr == NULL && mask == NULL) {
350 		entry->def.cipso = doi_def;
351 		entry->def.type = NETLBL_NLTYPE_CIPSOV4;
352 	} else if (addr != NULL && mask != NULL) {
353 		addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
354 		if (addrmap == NULL)
355 			goto out_addrmap;
356 		INIT_LIST_HEAD(&addrmap->list4);
357 		INIT_LIST_HEAD(&addrmap->list6);
358 
359 		addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC);
360 		if (addrinfo == NULL)
361 			goto out_addrinfo;
362 		addrinfo->def.cipso = doi_def;
363 		addrinfo->def.type = NETLBL_NLTYPE_CIPSOV4;
364 		addrinfo->list.addr = addr->s_addr & mask->s_addr;
365 		addrinfo->list.mask = mask->s_addr;
366 		addrinfo->list.valid = 1;
367 		ret_val = netlbl_af4list_add(&addrinfo->list, &addrmap->list4);
368 		if (ret_val != 0)
369 			goto cfg_cipsov4_map_add_failure;
370 
371 		entry->def.addrsel = addrmap;
372 		entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
373 	} else {
374 		ret_val = -EINVAL;
375 		goto out_addrmap;
376 	}
377 
378 	ret_val = netlbl_domhsh_add(entry, audit_info);
379 	if (ret_val != 0)
380 		goto cfg_cipsov4_map_add_failure;
381 
382 	return 0;
383 
384 cfg_cipsov4_map_add_failure:
385 	kfree(addrinfo);
386 out_addrinfo:
387 	kfree(addrmap);
388 out_addrmap:
389 	kfree(entry->domain);
390 out_domain:
391 	kfree(entry);
392 out_entry:
393 	cipso_v4_doi_putdef(doi_def);
394 	return ret_val;
395 }
396 
397 /**
398  * netlbl_cfg_calipso_add - Add a new CALIPSO DOI definition
399  * @doi_def: CALIPSO DOI definition
400  * @audit_info: NetLabel audit information
401  *
402  * Description:
403  * Add a new CALIPSO DOI definition as defined by @doi_def.  Returns zero on
404  * success and negative values on failure.
405  *
406  */
netlbl_cfg_calipso_add(struct calipso_doi * doi_def,struct netlbl_audit * audit_info)407 int netlbl_cfg_calipso_add(struct calipso_doi *doi_def,
408 			   struct netlbl_audit *audit_info)
409 {
410 #if IS_ENABLED(CONFIG_IPV6)
411 	return calipso_doi_add(doi_def, audit_info);
412 #else /* IPv6 */
413 	return -ENOSYS;
414 #endif /* IPv6 */
415 }
416 
417 /**
418  * netlbl_cfg_calipso_del - Remove an existing CALIPSO DOI definition
419  * @doi: CALIPSO DOI
420  * @audit_info: NetLabel audit information
421  *
422  * Description:
423  * Remove an existing CALIPSO DOI definition matching @doi.  Returns zero on
424  * success and negative values on failure.
425  *
426  */
netlbl_cfg_calipso_del(u32 doi,struct netlbl_audit * audit_info)427 void netlbl_cfg_calipso_del(u32 doi, struct netlbl_audit *audit_info)
428 {
429 #if IS_ENABLED(CONFIG_IPV6)
430 	calipso_doi_remove(doi, audit_info);
431 #endif /* IPv6 */
432 }
433 
434 /**
435  * netlbl_cfg_calipso_map_add - Add a new CALIPSO DOI mapping
436  * @doi: the CALIPSO DOI
437  * @domain: the domain mapping to add
438  * @addr: IP address
439  * @mask: IP address mask
440  * @audit_info: NetLabel audit information
441  *
442  * Description:
443  * Add a new NetLabel/LSM domain mapping for the given CALIPSO DOI to the
444  * NetLabel subsystem.  A @domain value of NULL adds a new default domain
445  * mapping.  Returns zero on success, negative values on failure.
446  *
447  */
netlbl_cfg_calipso_map_add(u32 doi,const char * domain,const struct in6_addr * addr,const struct in6_addr * mask,struct netlbl_audit * audit_info)448 int netlbl_cfg_calipso_map_add(u32 doi,
449 			       const char *domain,
450 			       const struct in6_addr *addr,
451 			       const struct in6_addr *mask,
452 			       struct netlbl_audit *audit_info)
453 {
454 #if IS_ENABLED(CONFIG_IPV6)
455 	int ret_val = -ENOMEM;
456 	struct calipso_doi *doi_def;
457 	struct netlbl_dom_map *entry;
458 	struct netlbl_domaddr_map *addrmap = NULL;
459 	struct netlbl_domaddr6_map *addrinfo = NULL;
460 
461 	doi_def = calipso_doi_getdef(doi);
462 	if (doi_def == NULL)
463 		return -ENOENT;
464 
465 	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
466 	if (entry == NULL)
467 		goto out_entry;
468 	entry->family = AF_INET6;
469 	if (domain != NULL) {
470 		entry->domain = kstrdup(domain, GFP_ATOMIC);
471 		if (entry->domain == NULL)
472 			goto out_domain;
473 	}
474 
475 	if (addr == NULL && mask == NULL) {
476 		entry->def.calipso = doi_def;
477 		entry->def.type = NETLBL_NLTYPE_CALIPSO;
478 	} else if (addr != NULL && mask != NULL) {
479 		addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
480 		if (addrmap == NULL)
481 			goto out_addrmap;
482 		INIT_LIST_HEAD(&addrmap->list4);
483 		INIT_LIST_HEAD(&addrmap->list6);
484 
485 		addrinfo = kzalloc(sizeof(*addrinfo), GFP_ATOMIC);
486 		if (addrinfo == NULL)
487 			goto out_addrinfo;
488 		addrinfo->def.calipso = doi_def;
489 		addrinfo->def.type = NETLBL_NLTYPE_CALIPSO;
490 		addrinfo->list.addr = *addr;
491 		addrinfo->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
492 		addrinfo->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
493 		addrinfo->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
494 		addrinfo->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
495 		addrinfo->list.mask = *mask;
496 		addrinfo->list.valid = 1;
497 		ret_val = netlbl_af6list_add(&addrinfo->list, &addrmap->list6);
498 		if (ret_val != 0)
499 			goto cfg_calipso_map_add_failure;
500 
501 		entry->def.addrsel = addrmap;
502 		entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
503 	} else {
504 		ret_val = -EINVAL;
505 		goto out_addrmap;
506 	}
507 
508 	ret_val = netlbl_domhsh_add(entry, audit_info);
509 	if (ret_val != 0)
510 		goto cfg_calipso_map_add_failure;
511 
512 	return 0;
513 
514 cfg_calipso_map_add_failure:
515 	kfree(addrinfo);
516 out_addrinfo:
517 	kfree(addrmap);
518 out_addrmap:
519 	kfree(entry->domain);
520 out_domain:
521 	kfree(entry);
522 out_entry:
523 	calipso_doi_putdef(doi_def);
524 	return ret_val;
525 #else /* IPv6 */
526 	return -ENOSYS;
527 #endif /* IPv6 */
528 }
529 
530 /*
531  * Security Attribute Functions
532  */
533 
534 #define _CM_F_NONE	0x00000000
535 #define _CM_F_ALLOC	0x00000001
536 #define _CM_F_WALK	0x00000002
537 
538 /**
539  * _netlbl_catmap_getnode - Get a individual node from a catmap
540  * @catmap: pointer to the category bitmap
541  * @offset: the requested offset
542  * @cm_flags: catmap flags, see _CM_F_*
543  * @gfp_flags: memory allocation flags
544  *
545  * Description:
546  * Iterate through the catmap looking for the node associated with @offset.
547  * If the _CM_F_ALLOC flag is set in @cm_flags and there is no associated node,
548  * one will be created and inserted into the catmap.  If the _CM_F_WALK flag is
549  * set in @cm_flags and there is no associated node, the next highest node will
550  * be returned.  Returns a pointer to the node on success, NULL on failure.
551  *
552  */
_netlbl_catmap_getnode(struct netlbl_lsm_catmap ** catmap,u32 offset,unsigned int cm_flags,gfp_t gfp_flags)553 static struct netlbl_lsm_catmap *_netlbl_catmap_getnode(
554 					     struct netlbl_lsm_catmap **catmap,
555 					     u32 offset,
556 					     unsigned int cm_flags,
557 					     gfp_t gfp_flags)
558 {
559 	struct netlbl_lsm_catmap *iter = *catmap;
560 	struct netlbl_lsm_catmap *prev = NULL;
561 
562 	if (iter == NULL)
563 		goto catmap_getnode_alloc;
564 	if (offset < iter->startbit)
565 		goto catmap_getnode_walk;
566 	while (iter && offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
567 		prev = iter;
568 		iter = iter->next;
569 	}
570 	if (iter == NULL || offset < iter->startbit)
571 		goto catmap_getnode_walk;
572 
573 	return iter;
574 
575 catmap_getnode_walk:
576 	if (cm_flags & _CM_F_WALK)
577 		return iter;
578 catmap_getnode_alloc:
579 	if (!(cm_flags & _CM_F_ALLOC))
580 		return NULL;
581 
582 	iter = netlbl_catmap_alloc(gfp_flags);
583 	if (iter == NULL)
584 		return NULL;
585 	iter->startbit = offset & ~(NETLBL_CATMAP_SIZE - 1);
586 
587 	if (prev == NULL) {
588 		iter->next = *catmap;
589 		*catmap = iter;
590 	} else {
591 		iter->next = prev->next;
592 		prev->next = iter;
593 	}
594 
595 	return iter;
596 }
597 
598 /**
599  * netlbl_catmap_walk - Walk a LSM secattr catmap looking for a bit
600  * @catmap: the category bitmap
601  * @offset: the offset to start searching at, in bits
602  *
603  * Description:
604  * This function walks a LSM secattr category bitmap starting at @offset and
605  * returns the spot of the first set bit or -ENOENT if no bits are set.
606  *
607  */
netlbl_catmap_walk(struct netlbl_lsm_catmap * catmap,u32 offset)608 int netlbl_catmap_walk(struct netlbl_lsm_catmap *catmap, u32 offset)
609 {
610 	struct netlbl_lsm_catmap *iter;
611 	u32 idx;
612 	u32 bit;
613 	NETLBL_CATMAP_MAPTYPE bitmap;
614 
615 	iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
616 	if (iter == NULL)
617 		return -ENOENT;
618 	if (offset > iter->startbit) {
619 		offset -= iter->startbit;
620 		idx = offset / NETLBL_CATMAP_MAPSIZE;
621 		bit = offset % NETLBL_CATMAP_MAPSIZE;
622 	} else {
623 		idx = 0;
624 		bit = 0;
625 	}
626 	bitmap = iter->bitmap[idx] >> bit;
627 
628 	for (;;) {
629 		if (bitmap != 0) {
630 			while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
631 				bitmap >>= 1;
632 				bit++;
633 			}
634 			return iter->startbit +
635 			       (NETLBL_CATMAP_MAPSIZE * idx) + bit;
636 		}
637 		if (++idx >= NETLBL_CATMAP_MAPCNT) {
638 			if (iter->next != NULL) {
639 				iter = iter->next;
640 				idx = 0;
641 			} else
642 				return -ENOENT;
643 		}
644 		bitmap = iter->bitmap[idx];
645 		bit = 0;
646 	}
647 
648 	return -ENOENT;
649 }
650 EXPORT_SYMBOL(netlbl_catmap_walk);
651 
652 /**
653  * netlbl_catmap_walkrng - Find the end of a string of set bits
654  * @catmap: the category bitmap
655  * @offset: the offset to start searching at, in bits
656  *
657  * Description:
658  * This function walks a LSM secattr category bitmap starting at @offset and
659  * returns the spot of the first cleared bit or -ENOENT if the offset is past
660  * the end of the bitmap.
661  *
662  */
netlbl_catmap_walkrng(struct netlbl_lsm_catmap * catmap,u32 offset)663 int netlbl_catmap_walkrng(struct netlbl_lsm_catmap *catmap, u32 offset)
664 {
665 	struct netlbl_lsm_catmap *iter;
666 	struct netlbl_lsm_catmap *prev = NULL;
667 	u32 idx;
668 	u32 bit;
669 	NETLBL_CATMAP_MAPTYPE bitmask;
670 	NETLBL_CATMAP_MAPTYPE bitmap;
671 
672 	iter = _netlbl_catmap_getnode(&catmap, offset, _CM_F_WALK, 0);
673 	if (iter == NULL)
674 		return -ENOENT;
675 	if (offset > iter->startbit) {
676 		offset -= iter->startbit;
677 		idx = offset / NETLBL_CATMAP_MAPSIZE;
678 		bit = offset % NETLBL_CATMAP_MAPSIZE;
679 	} else {
680 		idx = 0;
681 		bit = 0;
682 	}
683 	bitmask = NETLBL_CATMAP_BIT << bit;
684 
685 	for (;;) {
686 		bitmap = iter->bitmap[idx];
687 		while (bitmask != 0 && (bitmap & bitmask) != 0) {
688 			bitmask <<= 1;
689 			bit++;
690 		}
691 
692 		if (prev && idx == 0 && bit == 0)
693 			return prev->startbit + NETLBL_CATMAP_SIZE - 1;
694 		else if (bitmask != 0)
695 			return iter->startbit +
696 				(NETLBL_CATMAP_MAPSIZE * idx) + bit - 1;
697 		else if (++idx >= NETLBL_CATMAP_MAPCNT) {
698 			if (iter->next == NULL)
699 				return iter->startbit + NETLBL_CATMAP_SIZE - 1;
700 			prev = iter;
701 			iter = iter->next;
702 			idx = 0;
703 		}
704 		bitmask = NETLBL_CATMAP_BIT;
705 		bit = 0;
706 	}
707 
708 	return -ENOENT;
709 }
710 
711 /**
712  * netlbl_catmap_getlong - Export an unsigned long bitmap
713  * @catmap: pointer to the category bitmap
714  * @offset: pointer to the requested offset
715  * @bitmap: the exported bitmap
716  *
717  * Description:
718  * Export a bitmap with an offset greater than or equal to @offset and return
719  * it in @bitmap.  The @offset must be aligned to an unsigned long and will be
720  * updated on return if different from what was requested; if the catmap is
721  * empty at the requested offset and beyond, the @offset is set to (u32)-1.
722  * Returns zero on success, negative values on failure.
723  *
724  */
netlbl_catmap_getlong(struct netlbl_lsm_catmap * catmap,u32 * offset,unsigned long * bitmap)725 int netlbl_catmap_getlong(struct netlbl_lsm_catmap *catmap,
726 			  u32 *offset,
727 			  unsigned long *bitmap)
728 {
729 	struct netlbl_lsm_catmap *iter;
730 	u32 off = *offset;
731 	u32 idx;
732 
733 	/* only allow aligned offsets */
734 	if ((off & (BITS_PER_LONG - 1)) != 0)
735 		return -EINVAL;
736 
737 	/* a null catmap is equivalent to an empty one */
738 	if (!catmap) {
739 		*offset = (u32)-1;
740 		return 0;
741 	}
742 
743 	if (off < catmap->startbit) {
744 		off = catmap->startbit;
745 		*offset = off;
746 	}
747 	iter = _netlbl_catmap_getnode(&catmap, off, _CM_F_WALK, 0);
748 	if (iter == NULL) {
749 		*offset = (u32)-1;
750 		return 0;
751 	}
752 
753 	if (off < iter->startbit) {
754 		*offset = iter->startbit;
755 		off = 0;
756 	} else
757 		off -= iter->startbit;
758 	idx = off / NETLBL_CATMAP_MAPSIZE;
759 	*bitmap = iter->bitmap[idx] >> (off % NETLBL_CATMAP_MAPSIZE);
760 
761 	return 0;
762 }
763 
764 /**
765  * netlbl_catmap_setbit - Set a bit in a LSM secattr catmap
766  * @catmap: pointer to the category bitmap
767  * @bit: the bit to set
768  * @flags: memory allocation flags
769  *
770  * Description:
771  * Set the bit specified by @bit in @catmap.  Returns zero on success,
772  * negative values on failure.
773  *
774  */
netlbl_catmap_setbit(struct netlbl_lsm_catmap ** catmap,u32 bit,gfp_t flags)775 int netlbl_catmap_setbit(struct netlbl_lsm_catmap **catmap,
776 			 u32 bit,
777 			 gfp_t flags)
778 {
779 	struct netlbl_lsm_catmap *iter;
780 	u32 idx;
781 
782 	iter = _netlbl_catmap_getnode(catmap, bit, _CM_F_ALLOC, flags);
783 	if (iter == NULL)
784 		return -ENOMEM;
785 
786 	bit -= iter->startbit;
787 	idx = bit / NETLBL_CATMAP_MAPSIZE;
788 	iter->bitmap[idx] |= NETLBL_CATMAP_BIT << (bit % NETLBL_CATMAP_MAPSIZE);
789 
790 	return 0;
791 }
792 EXPORT_SYMBOL(netlbl_catmap_setbit);
793 
794 /**
795  * netlbl_catmap_setrng - Set a range of bits in a LSM secattr catmap
796  * @catmap: pointer to the category bitmap
797  * @start: the starting bit
798  * @end: the last bit in the string
799  * @flags: memory allocation flags
800  *
801  * Description:
802  * Set a range of bits, starting at @start and ending with @end.  Returns zero
803  * on success, negative values on failure.
804  *
805  */
netlbl_catmap_setrng(struct netlbl_lsm_catmap ** catmap,u32 start,u32 end,gfp_t flags)806 int netlbl_catmap_setrng(struct netlbl_lsm_catmap **catmap,
807 			 u32 start,
808 			 u32 end,
809 			 gfp_t flags)
810 {
811 	int rc = 0;
812 	u32 spot = start;
813 
814 	while (rc == 0 && spot <= end) {
815 		if (((spot & (BITS_PER_LONG - 1)) == 0) &&
816 		    ((end - spot) > BITS_PER_LONG)) {
817 			rc = netlbl_catmap_setlong(catmap,
818 						   spot,
819 						   (unsigned long)-1,
820 						   flags);
821 			spot += BITS_PER_LONG;
822 		} else
823 			rc = netlbl_catmap_setbit(catmap, spot++, flags);
824 	}
825 
826 	return rc;
827 }
828 
829 /**
830  * netlbl_catmap_setlong - Import an unsigned long bitmap
831  * @catmap: pointer to the category bitmap
832  * @offset: offset to the start of the imported bitmap
833  * @bitmap: the bitmap to import
834  * @flags: memory allocation flags
835  *
836  * Description:
837  * Import the bitmap specified in @bitmap into @catmap, using the offset
838  * in @offset.  The offset must be aligned to an unsigned long.  Returns zero
839  * on success, negative values on failure.
840  *
841  */
netlbl_catmap_setlong(struct netlbl_lsm_catmap ** catmap,u32 offset,unsigned long bitmap,gfp_t flags)842 int netlbl_catmap_setlong(struct netlbl_lsm_catmap **catmap,
843 			  u32 offset,
844 			  unsigned long bitmap,
845 			  gfp_t flags)
846 {
847 	struct netlbl_lsm_catmap *iter;
848 	u32 idx;
849 
850 	/* only allow aligned offsets */
851 	if ((offset & (BITS_PER_LONG - 1)) != 0)
852 		return -EINVAL;
853 
854 	iter = _netlbl_catmap_getnode(catmap, offset, _CM_F_ALLOC, flags);
855 	if (iter == NULL)
856 		return -ENOMEM;
857 
858 	offset -= iter->startbit;
859 	idx = offset / NETLBL_CATMAP_MAPSIZE;
860 	iter->bitmap[idx] |= bitmap << (offset % NETLBL_CATMAP_MAPSIZE);
861 
862 	return 0;
863 }
864 
865 /* Bitmap functions
866  */
867 
868 /**
869  * netlbl_bitmap_walk - Walk a bitmap looking for a bit
870  * @bitmap: the bitmap
871  * @bitmap_len: length in bits
872  * @offset: starting offset
873  * @state: if non-zero, look for a set (1) bit else look for a cleared (0) bit
874  *
875  * Description:
876  * Starting at @offset, walk the bitmap from left to right until either the
877  * desired bit is found or we reach the end.  Return the bit offset, -1 if
878  * not found, or -2 if error.
879  */
netlbl_bitmap_walk(const unsigned char * bitmap,u32 bitmap_len,u32 offset,u8 state)880 int netlbl_bitmap_walk(const unsigned char *bitmap, u32 bitmap_len,
881 		       u32 offset, u8 state)
882 {
883 	u32 bit_spot;
884 	u32 byte_offset;
885 	unsigned char bitmask;
886 	unsigned char byte;
887 
888 	if (offset >= bitmap_len)
889 		return -1;
890 	byte_offset = offset / 8;
891 	byte = bitmap[byte_offset];
892 	bit_spot = offset;
893 	bitmask = 0x80 >> (offset % 8);
894 
895 	while (bit_spot < bitmap_len) {
896 		if ((state && (byte & bitmask) == bitmask) ||
897 		    (state == 0 && (byte & bitmask) == 0))
898 			return bit_spot;
899 
900 		if (++bit_spot >= bitmap_len)
901 			return -1;
902 		bitmask >>= 1;
903 		if (bitmask == 0) {
904 			byte = bitmap[++byte_offset];
905 			bitmask = 0x80;
906 		}
907 	}
908 
909 	return -1;
910 }
911 EXPORT_SYMBOL(netlbl_bitmap_walk);
912 
913 /**
914  * netlbl_bitmap_setbit - Sets a single bit in a bitmap
915  * @bitmap: the bitmap
916  * @bit: the bit
917  * @state: if non-zero, set the bit (1) else clear the bit (0)
918  *
919  * Description:
920  * Set a single bit in the bitmask.  Returns zero on success, negative values
921  * on error.
922  */
netlbl_bitmap_setbit(unsigned char * bitmap,u32 bit,u8 state)923 void netlbl_bitmap_setbit(unsigned char *bitmap, u32 bit, u8 state)
924 {
925 	u32 byte_spot;
926 	u8 bitmask;
927 
928 	/* gcc always rounds to zero when doing integer division */
929 	byte_spot = bit / 8;
930 	bitmask = 0x80 >> (bit % 8);
931 	if (state)
932 		bitmap[byte_spot] |= bitmask;
933 	else
934 		bitmap[byte_spot] &= ~bitmask;
935 }
936 EXPORT_SYMBOL(netlbl_bitmap_setbit);
937 
938 /*
939  * LSM Functions
940  */
941 
942 /**
943  * netlbl_enabled - Determine if the NetLabel subsystem is enabled
944  *
945  * Description:
946  * The LSM can use this function to determine if it should use NetLabel
947  * security attributes in it's enforcement mechanism.  Currently, NetLabel is
948  * considered to be enabled when it's configuration contains a valid setup for
949  * at least one labeled protocol (i.e. NetLabel can understand incoming
950  * labeled packets of at least one type); otherwise NetLabel is considered to
951  * be disabled.
952  *
953  */
netlbl_enabled(void)954 int netlbl_enabled(void)
955 {
956 	/* At some point we probably want to expose this mechanism to the user
957 	 * as well so that admins can toggle NetLabel regardless of the
958 	 * configuration */
959 	return (atomic_read(&netlabel_mgmt_protocount) > 0);
960 }
961 
962 /**
963  * netlbl_sock_setattr - Label a socket using the correct protocol
964  * @sk: the socket to label
965  * @family: protocol family
966  * @secattr: the security attributes
967  *
968  * Description:
969  * Attach the correct label to the given socket using the security attributes
970  * specified in @secattr.  This function requires exclusive access to @sk,
971  * which means it either needs to be in the process of being created or locked.
972  * Returns zero on success, -EDESTADDRREQ if the domain is configured to use
973  * network address selectors (can't blindly label the socket), and negative
974  * values on all other failures.
975  *
976  */
netlbl_sock_setattr(struct sock * sk,u16 family,const struct netlbl_lsm_secattr * secattr)977 int netlbl_sock_setattr(struct sock *sk,
978 			u16 family,
979 			const struct netlbl_lsm_secattr *secattr)
980 {
981 	int ret_val;
982 	struct netlbl_dom_map *dom_entry;
983 
984 	rcu_read_lock();
985 	dom_entry = netlbl_domhsh_getentry(secattr->domain, family);
986 	if (dom_entry == NULL) {
987 		ret_val = -ENOENT;
988 		goto socket_setattr_return;
989 	}
990 	switch (family) {
991 	case AF_INET:
992 		switch (dom_entry->def.type) {
993 		case NETLBL_NLTYPE_ADDRSELECT:
994 			ret_val = -EDESTADDRREQ;
995 			break;
996 		case NETLBL_NLTYPE_CIPSOV4:
997 			ret_val = cipso_v4_sock_setattr(sk,
998 							dom_entry->def.cipso,
999 							secattr);
1000 			break;
1001 		case NETLBL_NLTYPE_UNLABELED:
1002 			ret_val = 0;
1003 			break;
1004 		default:
1005 			ret_val = -ENOENT;
1006 		}
1007 		break;
1008 #if IS_ENABLED(CONFIG_IPV6)
1009 	case AF_INET6:
1010 		switch (dom_entry->def.type) {
1011 		case NETLBL_NLTYPE_ADDRSELECT:
1012 			ret_val = -EDESTADDRREQ;
1013 			break;
1014 		case NETLBL_NLTYPE_CALIPSO:
1015 			ret_val = calipso_sock_setattr(sk,
1016 						       dom_entry->def.calipso,
1017 						       secattr);
1018 			break;
1019 		case NETLBL_NLTYPE_UNLABELED:
1020 			ret_val = 0;
1021 			break;
1022 		default:
1023 			ret_val = -ENOENT;
1024 		}
1025 		break;
1026 #endif /* IPv6 */
1027 	default:
1028 		ret_val = -EPROTONOSUPPORT;
1029 	}
1030 
1031 socket_setattr_return:
1032 	rcu_read_unlock();
1033 	return ret_val;
1034 }
1035 
1036 /**
1037  * netlbl_sock_delattr - Delete all the NetLabel labels on a socket
1038  * @sk: the socket
1039  *
1040  * Description:
1041  * Remove all the NetLabel labeling from @sk.  The caller is responsible for
1042  * ensuring that @sk is locked.
1043  *
1044  */
netlbl_sock_delattr(struct sock * sk)1045 void netlbl_sock_delattr(struct sock *sk)
1046 {
1047 	switch (sk->sk_family) {
1048 	case AF_INET:
1049 		cipso_v4_sock_delattr(sk);
1050 		break;
1051 #if IS_ENABLED(CONFIG_IPV6)
1052 	case AF_INET6:
1053 		calipso_sock_delattr(sk);
1054 		break;
1055 #endif /* IPv6 */
1056 	}
1057 }
1058 
1059 /**
1060  * netlbl_sock_getattr - Determine the security attributes of a sock
1061  * @sk: the sock
1062  * @secattr: the security attributes
1063  *
1064  * Description:
1065  * Examines the given sock to see if any NetLabel style labeling has been
1066  * applied to the sock, if so it parses the socket label and returns the
1067  * security attributes in @secattr.  Returns zero on success, negative values
1068  * on failure.
1069  *
1070  */
netlbl_sock_getattr(struct sock * sk,struct netlbl_lsm_secattr * secattr)1071 int netlbl_sock_getattr(struct sock *sk,
1072 			struct netlbl_lsm_secattr *secattr)
1073 {
1074 	int ret_val;
1075 
1076 	switch (sk->sk_family) {
1077 	case AF_INET:
1078 		ret_val = cipso_v4_sock_getattr(sk, secattr);
1079 		break;
1080 #if IS_ENABLED(CONFIG_IPV6)
1081 	case AF_INET6:
1082 		ret_val = calipso_sock_getattr(sk, secattr);
1083 		break;
1084 #endif /* IPv6 */
1085 	default:
1086 		ret_val = -EPROTONOSUPPORT;
1087 	}
1088 
1089 	return ret_val;
1090 }
1091 
1092 /**
1093  * netlbl_conn_setattr - Label a connected socket using the correct protocol
1094  * @sk: the socket to label
1095  * @addr: the destination address
1096  * @secattr: the security attributes
1097  *
1098  * Description:
1099  * Attach the correct label to the given connected socket using the security
1100  * attributes specified in @secattr.  The caller is responsible for ensuring
1101  * that @sk is locked.  Returns zero on success, negative values on failure.
1102  *
1103  */
netlbl_conn_setattr(struct sock * sk,struct sockaddr * addr,const struct netlbl_lsm_secattr * secattr)1104 int netlbl_conn_setattr(struct sock *sk,
1105 			struct sockaddr *addr,
1106 			const struct netlbl_lsm_secattr *secattr)
1107 {
1108 	int ret_val;
1109 	struct sockaddr_in *addr4;
1110 #if IS_ENABLED(CONFIG_IPV6)
1111 	struct sockaddr_in6 *addr6;
1112 #endif
1113 	struct netlbl_dommap_def *entry;
1114 
1115 	rcu_read_lock();
1116 	switch (addr->sa_family) {
1117 	case AF_INET:
1118 		addr4 = (struct sockaddr_in *)addr;
1119 		entry = netlbl_domhsh_getentry_af4(secattr->domain,
1120 						   addr4->sin_addr.s_addr);
1121 		if (entry == NULL) {
1122 			ret_val = -ENOENT;
1123 			goto conn_setattr_return;
1124 		}
1125 		switch (entry->type) {
1126 		case NETLBL_NLTYPE_CIPSOV4:
1127 			ret_val = cipso_v4_sock_setattr(sk,
1128 							entry->cipso, secattr);
1129 			break;
1130 		case NETLBL_NLTYPE_UNLABELED:
1131 			/* just delete the protocols we support for right now
1132 			 * but we could remove other protocols if needed */
1133 			netlbl_sock_delattr(sk);
1134 			ret_val = 0;
1135 			break;
1136 		default:
1137 			ret_val = -ENOENT;
1138 		}
1139 		break;
1140 #if IS_ENABLED(CONFIG_IPV6)
1141 	case AF_INET6:
1142 		addr6 = (struct sockaddr_in6 *)addr;
1143 		entry = netlbl_domhsh_getentry_af6(secattr->domain,
1144 						   &addr6->sin6_addr);
1145 		if (entry == NULL) {
1146 			ret_val = -ENOENT;
1147 			goto conn_setattr_return;
1148 		}
1149 		switch (entry->type) {
1150 		case NETLBL_NLTYPE_CALIPSO:
1151 			ret_val = calipso_sock_setattr(sk,
1152 						       entry->calipso, secattr);
1153 			break;
1154 		case NETLBL_NLTYPE_UNLABELED:
1155 			/* just delete the protocols we support for right now
1156 			 * but we could remove other protocols if needed */
1157 			netlbl_sock_delattr(sk);
1158 			ret_val = 0;
1159 			break;
1160 		default:
1161 			ret_val = -ENOENT;
1162 		}
1163 		break;
1164 #endif /* IPv6 */
1165 	default:
1166 		ret_val = -EPROTONOSUPPORT;
1167 	}
1168 
1169 conn_setattr_return:
1170 	rcu_read_unlock();
1171 	return ret_val;
1172 }
1173 
1174 /**
1175  * netlbl_req_setattr - Label a request socket using the correct protocol
1176  * @req: the request socket to label
1177  * @secattr: the security attributes
1178  *
1179  * Description:
1180  * Attach the correct label to the given socket using the security attributes
1181  * specified in @secattr.  Returns zero on success, negative values on failure.
1182  *
1183  */
netlbl_req_setattr(struct request_sock * req,const struct netlbl_lsm_secattr * secattr)1184 int netlbl_req_setattr(struct request_sock *req,
1185 		       const struct netlbl_lsm_secattr *secattr)
1186 {
1187 	int ret_val;
1188 	struct netlbl_dommap_def *entry;
1189 	struct inet_request_sock *ireq = inet_rsk(req);
1190 
1191 	rcu_read_lock();
1192 	switch (req->rsk_ops->family) {
1193 	case AF_INET:
1194 		entry = netlbl_domhsh_getentry_af4(secattr->domain,
1195 						   ireq->ir_rmt_addr);
1196 		if (entry == NULL) {
1197 			ret_val = -ENOENT;
1198 			goto req_setattr_return;
1199 		}
1200 		switch (entry->type) {
1201 		case NETLBL_NLTYPE_CIPSOV4:
1202 			ret_val = cipso_v4_req_setattr(req,
1203 						       entry->cipso, secattr);
1204 			break;
1205 		case NETLBL_NLTYPE_UNLABELED:
1206 			netlbl_req_delattr(req);
1207 			ret_val = 0;
1208 			break;
1209 		default:
1210 			ret_val = -ENOENT;
1211 		}
1212 		break;
1213 #if IS_ENABLED(CONFIG_IPV6)
1214 	case AF_INET6:
1215 		entry = netlbl_domhsh_getentry_af6(secattr->domain,
1216 						   &ireq->ir_v6_rmt_addr);
1217 		if (entry == NULL) {
1218 			ret_val = -ENOENT;
1219 			goto req_setattr_return;
1220 		}
1221 		switch (entry->type) {
1222 		case NETLBL_NLTYPE_CALIPSO:
1223 			ret_val = calipso_req_setattr(req,
1224 						      entry->calipso, secattr);
1225 			break;
1226 		case NETLBL_NLTYPE_UNLABELED:
1227 			netlbl_req_delattr(req);
1228 			ret_val = 0;
1229 			break;
1230 		default:
1231 			ret_val = -ENOENT;
1232 		}
1233 		break;
1234 #endif /* IPv6 */
1235 	default:
1236 		ret_val = -EPROTONOSUPPORT;
1237 	}
1238 
1239 req_setattr_return:
1240 	rcu_read_unlock();
1241 	return ret_val;
1242 }
1243 
1244 /**
1245 * netlbl_req_delattr - Delete all the NetLabel labels on a socket
1246 * @req: the socket
1247 *
1248 * Description:
1249 * Remove all the NetLabel labeling from @req.
1250 *
1251 */
netlbl_req_delattr(struct request_sock * req)1252 void netlbl_req_delattr(struct request_sock *req)
1253 {
1254 	switch (req->rsk_ops->family) {
1255 	case AF_INET:
1256 		cipso_v4_req_delattr(req);
1257 		break;
1258 #if IS_ENABLED(CONFIG_IPV6)
1259 	case AF_INET6:
1260 		calipso_req_delattr(req);
1261 		break;
1262 #endif /* IPv6 */
1263 	}
1264 }
1265 
1266 /**
1267  * netlbl_skbuff_setattr - Label a packet using the correct protocol
1268  * @skb: the packet
1269  * @family: protocol family
1270  * @secattr: the security attributes
1271  *
1272  * Description:
1273  * Attach the correct label to the given packet using the security attributes
1274  * specified in @secattr.  Returns zero on success, negative values on failure.
1275  *
1276  */
netlbl_skbuff_setattr(struct sk_buff * skb,u16 family,const struct netlbl_lsm_secattr * secattr)1277 int netlbl_skbuff_setattr(struct sk_buff *skb,
1278 			  u16 family,
1279 			  const struct netlbl_lsm_secattr *secattr)
1280 {
1281 	int ret_val;
1282 	struct iphdr *hdr4;
1283 #if IS_ENABLED(CONFIG_IPV6)
1284 	struct ipv6hdr *hdr6;
1285 #endif
1286 	struct netlbl_dommap_def *entry;
1287 
1288 	rcu_read_lock();
1289 	switch (family) {
1290 	case AF_INET:
1291 		hdr4 = ip_hdr(skb);
1292 		entry = netlbl_domhsh_getentry_af4(secattr->domain,
1293 						   hdr4->daddr);
1294 		if (entry == NULL) {
1295 			ret_val = -ENOENT;
1296 			goto skbuff_setattr_return;
1297 		}
1298 		switch (entry->type) {
1299 		case NETLBL_NLTYPE_CIPSOV4:
1300 			ret_val = cipso_v4_skbuff_setattr(skb, entry->cipso,
1301 							  secattr);
1302 			break;
1303 		case NETLBL_NLTYPE_UNLABELED:
1304 			/* just delete the protocols we support for right now
1305 			 * but we could remove other protocols if needed */
1306 			ret_val = cipso_v4_skbuff_delattr(skb);
1307 			break;
1308 		default:
1309 			ret_val = -ENOENT;
1310 		}
1311 		break;
1312 #if IS_ENABLED(CONFIG_IPV6)
1313 	case AF_INET6:
1314 		hdr6 = ipv6_hdr(skb);
1315 		entry = netlbl_domhsh_getentry_af6(secattr->domain,
1316 						   &hdr6->daddr);
1317 		if (entry == NULL) {
1318 			ret_val = -ENOENT;
1319 			goto skbuff_setattr_return;
1320 		}
1321 		switch (entry->type) {
1322 		case NETLBL_NLTYPE_CALIPSO:
1323 			ret_val = calipso_skbuff_setattr(skb, entry->calipso,
1324 							 secattr);
1325 			break;
1326 		case NETLBL_NLTYPE_UNLABELED:
1327 			/* just delete the protocols we support for right now
1328 			 * but we could remove other protocols if needed */
1329 			ret_val = calipso_skbuff_delattr(skb);
1330 			break;
1331 		default:
1332 			ret_val = -ENOENT;
1333 		}
1334 		break;
1335 #endif /* IPv6 */
1336 	default:
1337 		ret_val = -EPROTONOSUPPORT;
1338 	}
1339 
1340 skbuff_setattr_return:
1341 	rcu_read_unlock();
1342 	return ret_val;
1343 }
1344 
1345 /**
1346  * netlbl_skbuff_getattr - Determine the security attributes of a packet
1347  * @skb: the packet
1348  * @family: protocol family
1349  * @secattr: the security attributes
1350  *
1351  * Description:
1352  * Examines the given packet to see if a recognized form of packet labeling
1353  * is present, if so it parses the packet label and returns the security
1354  * attributes in @secattr.  Returns zero on success, negative values on
1355  * failure.
1356  *
1357  */
netlbl_skbuff_getattr(const struct sk_buff * skb,u16 family,struct netlbl_lsm_secattr * secattr)1358 int netlbl_skbuff_getattr(const struct sk_buff *skb,
1359 			  u16 family,
1360 			  struct netlbl_lsm_secattr *secattr)
1361 {
1362 	unsigned char *ptr;
1363 
1364 	switch (family) {
1365 	case AF_INET:
1366 		ptr = cipso_v4_optptr(skb);
1367 		if (ptr && cipso_v4_getattr(ptr, secattr) == 0)
1368 			return 0;
1369 		break;
1370 #if IS_ENABLED(CONFIG_IPV6)
1371 	case AF_INET6:
1372 		ptr = calipso_optptr(skb);
1373 		if (ptr && calipso_getattr(ptr, secattr) == 0)
1374 			return 0;
1375 		break;
1376 #endif /* IPv6 */
1377 	}
1378 
1379 	return netlbl_unlabel_getattr(skb, family, secattr);
1380 }
1381 
1382 /**
1383  * netlbl_skbuff_err - Handle a LSM error on a sk_buff
1384  * @skb: the packet
1385  * @family: the family
1386  * @error: the error code
1387  * @gateway: true if host is acting as a gateway, false otherwise
1388  *
1389  * Description:
1390  * Deal with a LSM problem when handling the packet in @skb, typically this is
1391  * a permission denied problem (-EACCES).  The correct action is determined
1392  * according to the packet's labeling protocol.
1393  *
1394  */
netlbl_skbuff_err(struct sk_buff * skb,u16 family,int error,int gateway)1395 void netlbl_skbuff_err(struct sk_buff *skb, u16 family, int error, int gateway)
1396 {
1397 	switch (family) {
1398 	case AF_INET:
1399 		if (cipso_v4_optptr(skb))
1400 			cipso_v4_error(skb, error, gateway);
1401 		break;
1402 	}
1403 }
1404 
1405 /**
1406  * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
1407  *
1408  * Description:
1409  * For all of the NetLabel protocols that support some form of label mapping
1410  * cache, invalidate the cache.  Returns zero on success, negative values on
1411  * error.
1412  *
1413  */
netlbl_cache_invalidate(void)1414 void netlbl_cache_invalidate(void)
1415 {
1416 	cipso_v4_cache_invalidate();
1417 #if IS_ENABLED(CONFIG_IPV6)
1418 	calipso_cache_invalidate();
1419 #endif /* IPv6 */
1420 }
1421 
1422 /**
1423  * netlbl_cache_add - Add an entry to a NetLabel protocol cache
1424  * @skb: the packet
1425  * @family: the family
1426  * @secattr: the packet's security attributes
1427  *
1428  * Description:
1429  * Add the LSM security attributes for the given packet to the underlying
1430  * NetLabel protocol's label mapping cache.  Returns zero on success, negative
1431  * values on error.
1432  *
1433  */
netlbl_cache_add(const struct sk_buff * skb,u16 family,const struct netlbl_lsm_secattr * secattr)1434 int netlbl_cache_add(const struct sk_buff *skb, u16 family,
1435 		     const struct netlbl_lsm_secattr *secattr)
1436 {
1437 	unsigned char *ptr;
1438 
1439 	if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
1440 		return -ENOMSG;
1441 
1442 	switch (family) {
1443 	case AF_INET:
1444 		ptr = cipso_v4_optptr(skb);
1445 		if (ptr)
1446 			return cipso_v4_cache_add(ptr, secattr);
1447 		break;
1448 #if IS_ENABLED(CONFIG_IPV6)
1449 	case AF_INET6:
1450 		ptr = calipso_optptr(skb);
1451 		if (ptr)
1452 			return calipso_cache_add(ptr, secattr);
1453 		break;
1454 #endif /* IPv6 */
1455 	}
1456 	return -ENOMSG;
1457 }
1458 
1459 /*
1460  * Protocol Engine Functions
1461  */
1462 
1463 /**
1464  * netlbl_audit_start - Start an audit message
1465  * @type: audit message type
1466  * @audit_info: NetLabel audit information
1467  *
1468  * Description:
1469  * Start an audit message using the type specified in @type and fill the audit
1470  * message with some fields common to all NetLabel audit messages.  This
1471  * function should only be used by protocol engines, not LSMs.  Returns a
1472  * pointer to the audit buffer on success, NULL on failure.
1473  *
1474  */
netlbl_audit_start(int type,struct netlbl_audit * audit_info)1475 struct audit_buffer *netlbl_audit_start(int type,
1476 					struct netlbl_audit *audit_info)
1477 {
1478 	return netlbl_audit_start_common(type, audit_info);
1479 }
1480 EXPORT_SYMBOL(netlbl_audit_start);
1481 
1482 /*
1483  * Setup Functions
1484  */
1485 
1486 /**
1487  * netlbl_init - Initialize NetLabel
1488  *
1489  * Description:
1490  * Perform the required NetLabel initialization before first use.
1491  *
1492  */
netlbl_init(void)1493 static int __init netlbl_init(void)
1494 {
1495 	int ret_val;
1496 
1497 	printk(KERN_INFO "NetLabel: Initializing\n");
1498 	printk(KERN_INFO "NetLabel:  domain hash size = %u\n",
1499 	       (1 << NETLBL_DOMHSH_BITSIZE));
1500 	printk(KERN_INFO "NetLabel:  protocols = UNLABELED CIPSOv4 CALIPSO\n");
1501 
1502 	ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
1503 	if (ret_val != 0)
1504 		goto init_failure;
1505 
1506 	ret_val = netlbl_unlabel_init(NETLBL_UNLHSH_BITSIZE);
1507 	if (ret_val != 0)
1508 		goto init_failure;
1509 
1510 	ret_val = netlbl_netlink_init();
1511 	if (ret_val != 0)
1512 		goto init_failure;
1513 
1514 	ret_val = netlbl_unlabel_defconf();
1515 	if (ret_val != 0)
1516 		goto init_failure;
1517 	printk(KERN_INFO "NetLabel:  unlabeled traffic allowed by default\n");
1518 
1519 	return 0;
1520 
1521 init_failure:
1522 	panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
1523 }
1524 
1525 subsys_initcall(netlbl_init);
1526