1 /*
2 * NetLabel Unlabeled Support
3 *
4 * This file defines functions for dealing with unlabeled packets for the
5 * NetLabel system. The NetLabel system manages static and dynamic label
6 * mappings for network 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 - 2008
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/rcupdate.h>
33 #include <linux/list.h>
34 #include <linux/spinlock.h>
35 #include <linux/socket.h>
36 #include <linux/string.h>
37 #include <linux/skbuff.h>
38 #include <linux/audit.h>
39 #include <linux/in.h>
40 #include <linux/in6.h>
41 #include <linux/ip.h>
42 #include <linux/ipv6.h>
43 #include <linux/notifier.h>
44 #include <linux/netdevice.h>
45 #include <linux/security.h>
46 #include <net/sock.h>
47 #include <net/netlink.h>
48 #include <net/genetlink.h>
49 #include <net/ip.h>
50 #include <net/ipv6.h>
51 #include <net/net_namespace.h>
52 #include <net/netlabel.h>
53 #include <asm/bug.h>
54 #include <asm/atomic.h>
55
56 #include "netlabel_user.h"
57 #include "netlabel_addrlist.h"
58 #include "netlabel_domainhash.h"
59 #include "netlabel_unlabeled.h"
60 #include "netlabel_mgmt.h"
61
62 /* NOTE: at present we always use init's network namespace since we don't
63 * presently support different namespaces even though the majority of
64 * the functions in this file are "namespace safe" */
65
66 /* The unlabeled connection hash table which we use to map network interfaces
67 * and addresses of unlabeled packets to a user specified secid value for the
68 * LSM. The hash table is used to lookup the network interface entry
69 * (struct netlbl_unlhsh_iface) and then the interface entry is used to
70 * lookup an IP address match from an ordered list. If a network interface
71 * match can not be found in the hash table then the default entry
72 * (netlbl_unlhsh_def) is used. The IP address entry list
73 * (struct netlbl_unlhsh_addr) is ordered such that the entries with a
74 * larger netmask come first.
75 */
76 struct netlbl_unlhsh_tbl {
77 struct list_head *tbl;
78 u32 size;
79 };
80 #define netlbl_unlhsh_addr4_entry(iter) \
81 container_of(iter, struct netlbl_unlhsh_addr4, list)
82 struct netlbl_unlhsh_addr4 {
83 u32 secid;
84
85 struct netlbl_af4list list;
86 struct rcu_head rcu;
87 };
88 #define netlbl_unlhsh_addr6_entry(iter) \
89 container_of(iter, struct netlbl_unlhsh_addr6, list)
90 struct netlbl_unlhsh_addr6 {
91 u32 secid;
92
93 struct netlbl_af6list list;
94 struct rcu_head rcu;
95 };
96 struct netlbl_unlhsh_iface {
97 int ifindex;
98 struct list_head addr4_list;
99 struct list_head addr6_list;
100
101 u32 valid;
102 struct list_head list;
103 struct rcu_head rcu;
104 };
105
106 /* Argument struct for netlbl_unlhsh_walk() */
107 struct netlbl_unlhsh_walk_arg {
108 struct netlink_callback *nl_cb;
109 struct sk_buff *skb;
110 u32 seq;
111 };
112
113 /* Unlabeled connection hash table */
114 /* updates should be so rare that having one spinlock for the entire
115 * hash table should be okay */
116 static DEFINE_SPINLOCK(netlbl_unlhsh_lock);
117 static struct netlbl_unlhsh_tbl *netlbl_unlhsh = NULL;
118 static struct netlbl_unlhsh_iface *netlbl_unlhsh_def = NULL;
119
120 /* Accept unlabeled packets flag */
121 static u8 netlabel_unlabel_acceptflg = 0;
122
123 /* NetLabel Generic NETLINK unlabeled family */
124 static struct genl_family netlbl_unlabel_gnl_family = {
125 .id = GENL_ID_GENERATE,
126 .hdrsize = 0,
127 .name = NETLBL_NLTYPE_UNLABELED_NAME,
128 .version = NETLBL_PROTO_VERSION,
129 .maxattr = NLBL_UNLABEL_A_MAX,
130 };
131
132 /* NetLabel Netlink attribute policy */
133 static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
134 [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
135 [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY,
136 .len = sizeof(struct in6_addr) },
137 [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY,
138 .len = sizeof(struct in6_addr) },
139 [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY,
140 .len = sizeof(struct in_addr) },
141 [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY,
142 .len = sizeof(struct in_addr) },
143 [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING,
144 .len = IFNAMSIZ - 1 },
145 [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY }
146 };
147
148 /*
149 * Unlabeled Connection Hash Table Functions
150 */
151
152 /**
153 * netlbl_unlhsh_free_addr4 - Frees an IPv4 address entry from the hash table
154 * @entry: the entry's RCU field
155 *
156 * Description:
157 * This function is designed to be used as a callback to the call_rcu()
158 * function so that memory allocated to a hash table address entry can be
159 * released safely.
160 *
161 */
netlbl_unlhsh_free_addr4(struct rcu_head * entry)162 static void netlbl_unlhsh_free_addr4(struct rcu_head *entry)
163 {
164 struct netlbl_unlhsh_addr4 *ptr;
165
166 ptr = container_of(entry, struct netlbl_unlhsh_addr4, rcu);
167 kfree(ptr);
168 }
169
170 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
171 /**
172 * netlbl_unlhsh_free_addr6 - Frees an IPv6 address entry from the hash table
173 * @entry: the entry's RCU field
174 *
175 * Description:
176 * This function is designed to be used as a callback to the call_rcu()
177 * function so that memory allocated to a hash table address entry can be
178 * released safely.
179 *
180 */
netlbl_unlhsh_free_addr6(struct rcu_head * entry)181 static void netlbl_unlhsh_free_addr6(struct rcu_head *entry)
182 {
183 struct netlbl_unlhsh_addr6 *ptr;
184
185 ptr = container_of(entry, struct netlbl_unlhsh_addr6, rcu);
186 kfree(ptr);
187 }
188 #endif /* IPv6 */
189
190 /**
191 * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table
192 * @entry: the entry's RCU field
193 *
194 * Description:
195 * This function is designed to be used as a callback to the call_rcu()
196 * function so that memory allocated to a hash table interface entry can be
197 * released safely. It is important to note that this function does not free
198 * the IPv4 and IPv6 address lists contained as part of an interface entry. It
199 * is up to the rest of the code to make sure an interface entry is only freed
200 * once it's address lists are empty.
201 *
202 */
netlbl_unlhsh_free_iface(struct rcu_head * entry)203 static void netlbl_unlhsh_free_iface(struct rcu_head *entry)
204 {
205 struct netlbl_unlhsh_iface *iface;
206 struct netlbl_af4list *iter4;
207 struct netlbl_af4list *tmp4;
208 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
209 struct netlbl_af6list *iter6;
210 struct netlbl_af6list *tmp6;
211 #endif /* IPv6 */
212
213 iface = container_of(entry, struct netlbl_unlhsh_iface, rcu);
214
215 /* no need for locks here since we are the only one with access to this
216 * structure */
217
218 netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) {
219 netlbl_af4list_remove_entry(iter4);
220 kfree(netlbl_unlhsh_addr4_entry(iter4));
221 }
222 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
223 netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) {
224 netlbl_af6list_remove_entry(iter6);
225 kfree(netlbl_unlhsh_addr6_entry(iter6));
226 }
227 #endif /* IPv6 */
228 kfree(iface);
229 }
230
231 /**
232 * netlbl_unlhsh_hash - Hashing function for the hash table
233 * @ifindex: the network interface/device to hash
234 *
235 * Description:
236 * This is the hashing function for the unlabeled hash table, it returns the
237 * bucket number for the given device/interface. The caller is responsible for
238 * calling the rcu_read_[un]lock() functions.
239 *
240 */
netlbl_unlhsh_hash(int ifindex)241 static u32 netlbl_unlhsh_hash(int ifindex)
242 {
243 /* this is taken _almost_ directly from
244 * security/selinux/netif.c:sel_netif_hasfn() as they do pretty much
245 * the same thing */
246 return ifindex & (rcu_dereference(netlbl_unlhsh)->size - 1);
247 }
248
249 /**
250 * netlbl_unlhsh_search_iface - Search for a matching interface entry
251 * @ifindex: the network interface
252 *
253 * Description:
254 * Searches the unlabeled connection hash table and returns a pointer to the
255 * interface entry which matches @ifindex, otherwise NULL is returned. The
256 * caller is responsible for calling the rcu_read_[un]lock() functions.
257 *
258 */
netlbl_unlhsh_search_iface(int ifindex)259 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
260 {
261 u32 bkt;
262 struct list_head *bkt_list;
263 struct netlbl_unlhsh_iface *iter;
264
265 bkt = netlbl_unlhsh_hash(ifindex);
266 bkt_list = &rcu_dereference(netlbl_unlhsh)->tbl[bkt];
267 list_for_each_entry_rcu(iter, bkt_list, list)
268 if (iter->valid && iter->ifindex == ifindex)
269 return iter;
270
271 return NULL;
272 }
273
274 /**
275 * netlbl_unlhsh_search_iface_def - Search for a matching interface entry
276 * @ifindex: the network interface
277 *
278 * Description:
279 * Searches the unlabeled connection hash table and returns a pointer to the
280 * interface entry which matches @ifindex. If an exact match can not be found
281 * and there is a valid default entry, the default entry is returned, otherwise
282 * NULL is returned. The caller is responsible for calling the
283 * rcu_read_[un]lock() functions.
284 *
285 */
netlbl_unlhsh_search_iface_def(int ifindex)286 static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface_def(int ifindex)
287 {
288 struct netlbl_unlhsh_iface *entry;
289
290 entry = netlbl_unlhsh_search_iface(ifindex);
291 if (entry != NULL)
292 return entry;
293
294 entry = rcu_dereference(netlbl_unlhsh_def);
295 if (entry != NULL && entry->valid)
296 return entry;
297
298 return NULL;
299 }
300
301 /**
302 * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table
303 * @iface: the associated interface entry
304 * @addr: IPv4 address in network byte order
305 * @mask: IPv4 address mask in network byte order
306 * @secid: LSM secid value for entry
307 *
308 * Description:
309 * Add a new address entry into the unlabeled connection hash table using the
310 * interface entry specified by @iface. On success zero is returned, otherwise
311 * a negative value is returned. The caller is responsible for calling the
312 * rcu_read_[un]lock() functions.
313 *
314 */
netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface * iface,const struct in_addr * addr,const struct in_addr * mask,u32 secid)315 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
316 const struct in_addr *addr,
317 const struct in_addr *mask,
318 u32 secid)
319 {
320 int ret_val;
321 struct netlbl_unlhsh_addr4 *entry;
322
323 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
324 if (entry == NULL)
325 return -ENOMEM;
326
327 entry->list.addr = addr->s_addr & mask->s_addr;
328 entry->list.mask = mask->s_addr;
329 entry->list.valid = 1;
330 INIT_RCU_HEAD(&entry->rcu);
331 entry->secid = secid;
332
333 spin_lock(&netlbl_unlhsh_lock);
334 ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
335 spin_unlock(&netlbl_unlhsh_lock);
336
337 if (ret_val != 0)
338 kfree(entry);
339 return ret_val;
340 }
341
342 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
343 /**
344 * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table
345 * @iface: the associated interface entry
346 * @addr: IPv6 address in network byte order
347 * @mask: IPv6 address mask in network byte order
348 * @secid: LSM secid value for entry
349 *
350 * Description:
351 * Add a new address entry into the unlabeled connection hash table using the
352 * interface entry specified by @iface. On success zero is returned, otherwise
353 * a negative value is returned. The caller is responsible for calling the
354 * rcu_read_[un]lock() functions.
355 *
356 */
netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface * iface,const struct in6_addr * addr,const struct in6_addr * mask,u32 secid)357 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
358 const struct in6_addr *addr,
359 const struct in6_addr *mask,
360 u32 secid)
361 {
362 int ret_val;
363 struct netlbl_unlhsh_addr6 *entry;
364
365 entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
366 if (entry == NULL)
367 return -ENOMEM;
368
369 ipv6_addr_copy(&entry->list.addr, addr);
370 entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
371 entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1];
372 entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2];
373 entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
374 ipv6_addr_copy(&entry->list.mask, mask);
375 entry->list.valid = 1;
376 INIT_RCU_HEAD(&entry->rcu);
377 entry->secid = secid;
378
379 spin_lock(&netlbl_unlhsh_lock);
380 ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
381 spin_unlock(&netlbl_unlhsh_lock);
382
383 if (ret_val != 0)
384 kfree(entry);
385 return 0;
386 }
387 #endif /* IPv6 */
388
389 /**
390 * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table
391 * @ifindex: network interface
392 *
393 * Description:
394 * Add a new, empty, interface entry into the unlabeled connection hash table.
395 * On success a pointer to the new interface entry is returned, on failure NULL
396 * is returned. The caller is responsible for calling the rcu_read_[un]lock()
397 * functions.
398 *
399 */
netlbl_unlhsh_add_iface(int ifindex)400 static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex)
401 {
402 u32 bkt;
403 struct netlbl_unlhsh_iface *iface;
404
405 iface = kzalloc(sizeof(*iface), GFP_ATOMIC);
406 if (iface == NULL)
407 return NULL;
408
409 iface->ifindex = ifindex;
410 INIT_LIST_HEAD(&iface->addr4_list);
411 INIT_LIST_HEAD(&iface->addr6_list);
412 iface->valid = 1;
413 INIT_RCU_HEAD(&iface->rcu);
414
415 spin_lock(&netlbl_unlhsh_lock);
416 if (ifindex > 0) {
417 bkt = netlbl_unlhsh_hash(ifindex);
418 if (netlbl_unlhsh_search_iface(ifindex) != NULL)
419 goto add_iface_failure;
420 list_add_tail_rcu(&iface->list,
421 &rcu_dereference(netlbl_unlhsh)->tbl[bkt]);
422 } else {
423 INIT_LIST_HEAD(&iface->list);
424 if (rcu_dereference(netlbl_unlhsh_def) != NULL)
425 goto add_iface_failure;
426 rcu_assign_pointer(netlbl_unlhsh_def, iface);
427 }
428 spin_unlock(&netlbl_unlhsh_lock);
429
430 return iface;
431
432 add_iface_failure:
433 spin_unlock(&netlbl_unlhsh_lock);
434 kfree(iface);
435 return NULL;
436 }
437
438 /**
439 * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table
440 * @net: network namespace
441 * @dev_name: interface name
442 * @addr: IP address in network byte order
443 * @mask: address mask in network byte order
444 * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
445 * @secid: LSM secid value for the entry
446 * @audit_info: NetLabel audit information
447 *
448 * Description:
449 * Adds a new entry to the unlabeled connection hash table. Returns zero on
450 * success, negative values on failure.
451 *
452 */
netlbl_unlhsh_add(struct net * net,const char * dev_name,const void * addr,const void * mask,u32 addr_len,u32 secid,struct netlbl_audit * audit_info)453 int netlbl_unlhsh_add(struct net *net,
454 const char *dev_name,
455 const void *addr,
456 const void *mask,
457 u32 addr_len,
458 u32 secid,
459 struct netlbl_audit *audit_info)
460 {
461 int ret_val;
462 int ifindex;
463 struct net_device *dev;
464 struct netlbl_unlhsh_iface *iface;
465 struct audit_buffer *audit_buf = NULL;
466 char *secctx = NULL;
467 u32 secctx_len;
468
469 if (addr_len != sizeof(struct in_addr) &&
470 addr_len != sizeof(struct in6_addr))
471 return -EINVAL;
472
473 rcu_read_lock();
474 if (dev_name != NULL) {
475 dev = dev_get_by_name(net, dev_name);
476 if (dev == NULL) {
477 ret_val = -ENODEV;
478 goto unlhsh_add_return;
479 }
480 ifindex = dev->ifindex;
481 dev_put(dev);
482 iface = netlbl_unlhsh_search_iface(ifindex);
483 } else {
484 ifindex = 0;
485 iface = rcu_dereference(netlbl_unlhsh_def);
486 }
487 if (iface == NULL) {
488 iface = netlbl_unlhsh_add_iface(ifindex);
489 if (iface == NULL) {
490 ret_val = -ENOMEM;
491 goto unlhsh_add_return;
492 }
493 }
494 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD,
495 audit_info);
496 switch (addr_len) {
497 case sizeof(struct in_addr): {
498 struct in_addr *addr4, *mask4;
499
500 addr4 = (struct in_addr *)addr;
501 mask4 = (struct in_addr *)mask;
502 ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
503 if (audit_buf != NULL)
504 netlbl_af4list_audit_addr(audit_buf, 1,
505 dev_name,
506 addr4->s_addr,
507 mask4->s_addr);
508 break;
509 }
510 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
511 case sizeof(struct in6_addr): {
512 struct in6_addr *addr6, *mask6;
513
514 addr6 = (struct in6_addr *)addr;
515 mask6 = (struct in6_addr *)mask;
516 ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
517 if (audit_buf != NULL)
518 netlbl_af6list_audit_addr(audit_buf, 1,
519 dev_name,
520 addr6, mask6);
521 break;
522 }
523 #endif /* IPv6 */
524 default:
525 ret_val = -EINVAL;
526 }
527 if (ret_val == 0)
528 atomic_inc(&netlabel_mgmt_protocount);
529
530 unlhsh_add_return:
531 rcu_read_unlock();
532 if (audit_buf != NULL) {
533 if (security_secid_to_secctx(secid,
534 &secctx,
535 &secctx_len) == 0) {
536 audit_log_format(audit_buf, " sec_obj=%s", secctx);
537 security_release_secctx(secctx, secctx_len);
538 }
539 audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
540 audit_log_end(audit_buf);
541 }
542 return ret_val;
543 }
544
545 /**
546 * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry
547 * @net: network namespace
548 * @iface: interface entry
549 * @addr: IP address
550 * @mask: IP address mask
551 * @audit_info: NetLabel audit information
552 *
553 * Description:
554 * Remove an IP address entry from the unlabeled connection hash table.
555 * Returns zero on success, negative values on failure. The caller is
556 * responsible for calling the rcu_read_[un]lock() functions.
557 *
558 */
netlbl_unlhsh_remove_addr4(struct net * net,struct netlbl_unlhsh_iface * iface,const struct in_addr * addr,const struct in_addr * mask,struct netlbl_audit * audit_info)559 static int netlbl_unlhsh_remove_addr4(struct net *net,
560 struct netlbl_unlhsh_iface *iface,
561 const struct in_addr *addr,
562 const struct in_addr *mask,
563 struct netlbl_audit *audit_info)
564 {
565 struct netlbl_af4list *list_entry;
566 struct netlbl_unlhsh_addr4 *entry;
567 struct audit_buffer *audit_buf;
568 struct net_device *dev;
569 char *secctx;
570 u32 secctx_len;
571
572 spin_lock(&netlbl_unlhsh_lock);
573 list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
574 &iface->addr4_list);
575 spin_unlock(&netlbl_unlhsh_lock);
576 if (list_entry != NULL)
577 entry = netlbl_unlhsh_addr4_entry(list_entry);
578 else
579 entry = NULL;
580
581 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
582 audit_info);
583 if (audit_buf != NULL) {
584 dev = dev_get_by_index(net, iface->ifindex);
585 netlbl_af4list_audit_addr(audit_buf, 1,
586 (dev != NULL ? dev->name : NULL),
587 addr->s_addr, mask->s_addr);
588 if (dev != NULL)
589 dev_put(dev);
590 if (entry != NULL &&
591 security_secid_to_secctx(entry->secid,
592 &secctx, &secctx_len) == 0) {
593 audit_log_format(audit_buf, " sec_obj=%s", secctx);
594 security_release_secctx(secctx, secctx_len);
595 }
596 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
597 audit_log_end(audit_buf);
598 }
599
600 if (entry == NULL)
601 return -ENOENT;
602
603 call_rcu(&entry->rcu, netlbl_unlhsh_free_addr4);
604 return 0;
605 }
606
607 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
608 /**
609 * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry
610 * @net: network namespace
611 * @iface: interface entry
612 * @addr: IP address
613 * @mask: IP address mask
614 * @audit_info: NetLabel audit information
615 *
616 * Description:
617 * Remove an IP address entry from the unlabeled connection hash table.
618 * Returns zero on success, negative values on failure. The caller is
619 * responsible for calling the rcu_read_[un]lock() functions.
620 *
621 */
netlbl_unlhsh_remove_addr6(struct net * net,struct netlbl_unlhsh_iface * iface,const struct in6_addr * addr,const struct in6_addr * mask,struct netlbl_audit * audit_info)622 static int netlbl_unlhsh_remove_addr6(struct net *net,
623 struct netlbl_unlhsh_iface *iface,
624 const struct in6_addr *addr,
625 const struct in6_addr *mask,
626 struct netlbl_audit *audit_info)
627 {
628 struct netlbl_af6list *list_entry;
629 struct netlbl_unlhsh_addr6 *entry;
630 struct audit_buffer *audit_buf;
631 struct net_device *dev;
632 char *secctx;
633 u32 secctx_len;
634
635 spin_lock(&netlbl_unlhsh_lock);
636 list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
637 spin_unlock(&netlbl_unlhsh_lock);
638 if (list_entry != NULL)
639 entry = netlbl_unlhsh_addr6_entry(list_entry);
640 else
641 entry = NULL;
642
643 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL,
644 audit_info);
645 if (audit_buf != NULL) {
646 dev = dev_get_by_index(net, iface->ifindex);
647 netlbl_af6list_audit_addr(audit_buf, 1,
648 (dev != NULL ? dev->name : NULL),
649 addr, mask);
650 if (dev != NULL)
651 dev_put(dev);
652 if (entry != NULL &&
653 security_secid_to_secctx(entry->secid,
654 &secctx, &secctx_len) == 0) {
655 audit_log_format(audit_buf, " sec_obj=%s", secctx);
656 security_release_secctx(secctx, secctx_len);
657 }
658 audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
659 audit_log_end(audit_buf);
660 }
661
662 if (entry == NULL)
663 return -ENOENT;
664
665 call_rcu(&entry->rcu, netlbl_unlhsh_free_addr6);
666 return 0;
667 }
668 #endif /* IPv6 */
669
670 /**
671 * netlbl_unlhsh_condremove_iface - Remove an interface entry
672 * @iface: the interface entry
673 *
674 * Description:
675 * Remove an interface entry from the unlabeled connection hash table if it is
676 * empty. An interface entry is considered to be empty if there are no
677 * address entries assigned to it.
678 *
679 */
netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface * iface)680 static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface)
681 {
682 struct netlbl_af4list *iter4;
683 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
684 struct netlbl_af6list *iter6;
685 #endif /* IPv6 */
686
687 spin_lock(&netlbl_unlhsh_lock);
688 netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list)
689 goto unlhsh_condremove_failure;
690 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
691 netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list)
692 goto unlhsh_condremove_failure;
693 #endif /* IPv6 */
694 iface->valid = 0;
695 if (iface->ifindex > 0)
696 list_del_rcu(&iface->list);
697 else
698 rcu_assign_pointer(netlbl_unlhsh_def, NULL);
699 spin_unlock(&netlbl_unlhsh_lock);
700
701 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
702 return;
703
704 unlhsh_condremove_failure:
705 spin_unlock(&netlbl_unlhsh_lock);
706 return;
707 }
708
709 /**
710 * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table
711 * @net: network namespace
712 * @dev_name: interface name
713 * @addr: IP address in network byte order
714 * @mask: address mask in network byte order
715 * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6)
716 * @audit_info: NetLabel audit information
717 *
718 * Description:
719 * Removes and existing entry from the unlabeled connection hash table.
720 * Returns zero on success, negative values on failure.
721 *
722 */
netlbl_unlhsh_remove(struct net * net,const char * dev_name,const void * addr,const void * mask,u32 addr_len,struct netlbl_audit * audit_info)723 int netlbl_unlhsh_remove(struct net *net,
724 const char *dev_name,
725 const void *addr,
726 const void *mask,
727 u32 addr_len,
728 struct netlbl_audit *audit_info)
729 {
730 int ret_val;
731 struct net_device *dev;
732 struct netlbl_unlhsh_iface *iface;
733
734 if (addr_len != sizeof(struct in_addr) &&
735 addr_len != sizeof(struct in6_addr))
736 return -EINVAL;
737
738 rcu_read_lock();
739 if (dev_name != NULL) {
740 dev = dev_get_by_name(net, dev_name);
741 if (dev == NULL) {
742 ret_val = -ENODEV;
743 goto unlhsh_remove_return;
744 }
745 iface = netlbl_unlhsh_search_iface(dev->ifindex);
746 dev_put(dev);
747 } else
748 iface = rcu_dereference(netlbl_unlhsh_def);
749 if (iface == NULL) {
750 ret_val = -ENOENT;
751 goto unlhsh_remove_return;
752 }
753 switch (addr_len) {
754 case sizeof(struct in_addr):
755 ret_val = netlbl_unlhsh_remove_addr4(net,
756 iface, addr, mask,
757 audit_info);
758 break;
759 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
760 case sizeof(struct in6_addr):
761 ret_val = netlbl_unlhsh_remove_addr6(net,
762 iface, addr, mask,
763 audit_info);
764 break;
765 #endif /* IPv6 */
766 default:
767 ret_val = -EINVAL;
768 }
769 if (ret_val == 0) {
770 netlbl_unlhsh_condremove_iface(iface);
771 atomic_dec(&netlabel_mgmt_protocount);
772 }
773
774 unlhsh_remove_return:
775 rcu_read_unlock();
776 return ret_val;
777 }
778
779 /*
780 * General Helper Functions
781 */
782
783 /**
784 * netlbl_unlhsh_netdev_handler - Network device notification handler
785 * @this: notifier block
786 * @event: the event
787 * @ptr: the network device (cast to void)
788 *
789 * Description:
790 * Handle network device events, although at present all we care about is a
791 * network device going away. In the case of a device going away we clear any
792 * related entries from the unlabeled connection hash table.
793 *
794 */
netlbl_unlhsh_netdev_handler(struct notifier_block * this,unsigned long event,void * ptr)795 static int netlbl_unlhsh_netdev_handler(struct notifier_block *this,
796 unsigned long event,
797 void *ptr)
798 {
799 struct net_device *dev = ptr;
800 struct netlbl_unlhsh_iface *iface = NULL;
801
802 if (!net_eq(dev_net(dev), &init_net))
803 return NOTIFY_DONE;
804
805 /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */
806 if (event == NETDEV_DOWN) {
807 spin_lock(&netlbl_unlhsh_lock);
808 iface = netlbl_unlhsh_search_iface(dev->ifindex);
809 if (iface != NULL && iface->valid) {
810 iface->valid = 0;
811 list_del_rcu(&iface->list);
812 } else
813 iface = NULL;
814 spin_unlock(&netlbl_unlhsh_lock);
815 }
816
817 if (iface != NULL)
818 call_rcu(&iface->rcu, netlbl_unlhsh_free_iface);
819
820 return NOTIFY_DONE;
821 }
822
823 /**
824 * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
825 * @value: desired value
826 * @audit_info: NetLabel audit information
827 *
828 * Description:
829 * Set the value of the unlabeled accept flag to @value.
830 *
831 */
netlbl_unlabel_acceptflg_set(u8 value,struct netlbl_audit * audit_info)832 static void netlbl_unlabel_acceptflg_set(u8 value,
833 struct netlbl_audit *audit_info)
834 {
835 struct audit_buffer *audit_buf;
836 u8 old_val;
837
838 old_val = netlabel_unlabel_acceptflg;
839 netlabel_unlabel_acceptflg = value;
840 audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
841 audit_info);
842 if (audit_buf != NULL) {
843 audit_log_format(audit_buf,
844 " unlbl_accept=%u old=%u", value, old_val);
845 audit_log_end(audit_buf);
846 }
847 }
848
849 /**
850 * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information
851 * @info: the Generic NETLINK info block
852 * @addr: the IP address
853 * @mask: the IP address mask
854 * @len: the address length
855 *
856 * Description:
857 * Examine the Generic NETLINK message and extract the IP address information.
858 * Returns zero on success, negative values on failure.
859 *
860 */
netlbl_unlabel_addrinfo_get(struct genl_info * info,void ** addr,void ** mask,u32 * len)861 static int netlbl_unlabel_addrinfo_get(struct genl_info *info,
862 void **addr,
863 void **mask,
864 u32 *len)
865 {
866 u32 addr_len;
867
868 if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR]) {
869 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
870 if (addr_len != sizeof(struct in_addr) &&
871 addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK]))
872 return -EINVAL;
873 *len = addr_len;
874 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]);
875 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]);
876 return 0;
877 } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) {
878 addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
879 if (addr_len != sizeof(struct in6_addr) &&
880 addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK]))
881 return -EINVAL;
882 *len = addr_len;
883 *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]);
884 *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]);
885 return 0;
886 }
887
888 return -EINVAL;
889 }
890
891 /*
892 * NetLabel Command Handlers
893 */
894
895 /**
896 * netlbl_unlabel_accept - Handle an ACCEPT message
897 * @skb: the NETLINK buffer
898 * @info: the Generic NETLINK info block
899 *
900 * Description:
901 * Process a user generated ACCEPT message and set the accept flag accordingly.
902 * Returns zero on success, negative values on failure.
903 *
904 */
netlbl_unlabel_accept(struct sk_buff * skb,struct genl_info * info)905 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
906 {
907 u8 value;
908 struct netlbl_audit audit_info;
909
910 if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
911 value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
912 if (value == 1 || value == 0) {
913 netlbl_netlink_auditinfo(skb, &audit_info);
914 netlbl_unlabel_acceptflg_set(value, &audit_info);
915 return 0;
916 }
917 }
918
919 return -EINVAL;
920 }
921
922 /**
923 * netlbl_unlabel_list - Handle a LIST message
924 * @skb: the NETLINK buffer
925 * @info: the Generic NETLINK info block
926 *
927 * Description:
928 * Process a user generated LIST message and respond with the current status.
929 * Returns zero on success, negative values on failure.
930 *
931 */
netlbl_unlabel_list(struct sk_buff * skb,struct genl_info * info)932 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
933 {
934 int ret_val = -EINVAL;
935 struct sk_buff *ans_skb;
936 void *data;
937
938 ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
939 if (ans_skb == NULL)
940 goto list_failure;
941 data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family,
942 0, NLBL_UNLABEL_C_LIST);
943 if (data == NULL) {
944 ret_val = -ENOMEM;
945 goto list_failure;
946 }
947
948 ret_val = nla_put_u8(ans_skb,
949 NLBL_UNLABEL_A_ACPTFLG,
950 netlabel_unlabel_acceptflg);
951 if (ret_val != 0)
952 goto list_failure;
953
954 genlmsg_end(ans_skb, data);
955 return genlmsg_reply(ans_skb, info);
956
957 list_failure:
958 kfree_skb(ans_skb);
959 return ret_val;
960 }
961
962 /**
963 * netlbl_unlabel_staticadd - Handle a STATICADD message
964 * @skb: the NETLINK buffer
965 * @info: the Generic NETLINK info block
966 *
967 * Description:
968 * Process a user generated STATICADD message and add a new unlabeled
969 * connection entry to the hash table. Returns zero on success, negative
970 * values on failure.
971 *
972 */
netlbl_unlabel_staticadd(struct sk_buff * skb,struct genl_info * info)973 static int netlbl_unlabel_staticadd(struct sk_buff *skb,
974 struct genl_info *info)
975 {
976 int ret_val;
977 char *dev_name;
978 void *addr;
979 void *mask;
980 u32 addr_len;
981 u32 secid;
982 struct netlbl_audit audit_info;
983
984 /* Don't allow users to add both IPv4 and IPv6 addresses for a
985 * single entry. However, allow users to create two entries, one each
986 * for IPv4 and IPv4, with the same LSM security context which should
987 * achieve the same result. */
988 if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
989 !info->attrs[NLBL_UNLABEL_A_IFACE] ||
990 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
991 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
992 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
993 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
994 return -EINVAL;
995
996 netlbl_netlink_auditinfo(skb, &audit_info);
997
998 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
999 if (ret_val != 0)
1000 return ret_val;
1001 dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1002 ret_val = security_secctx_to_secid(
1003 nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1004 nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1005 &secid);
1006 if (ret_val != 0)
1007 return ret_val;
1008
1009 return netlbl_unlhsh_add(&init_net,
1010 dev_name, addr, mask, addr_len, secid,
1011 &audit_info);
1012 }
1013
1014 /**
1015 * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message
1016 * @skb: the NETLINK buffer
1017 * @info: the Generic NETLINK info block
1018 *
1019 * Description:
1020 * Process a user generated STATICADDDEF message and add a new default
1021 * unlabeled connection entry. Returns zero on success, negative values on
1022 * failure.
1023 *
1024 */
netlbl_unlabel_staticadddef(struct sk_buff * skb,struct genl_info * info)1025 static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
1026 struct genl_info *info)
1027 {
1028 int ret_val;
1029 void *addr;
1030 void *mask;
1031 u32 addr_len;
1032 u32 secid;
1033 struct netlbl_audit audit_info;
1034
1035 /* Don't allow users to add both IPv4 and IPv6 addresses for a
1036 * single entry. However, allow users to create two entries, one each
1037 * for IPv4 and IPv6, with the same LSM security context which should
1038 * achieve the same result. */
1039 if (!info->attrs[NLBL_UNLABEL_A_SECCTX] ||
1040 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1041 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1042 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1043 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1044 return -EINVAL;
1045
1046 netlbl_netlink_auditinfo(skb, &audit_info);
1047
1048 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1049 if (ret_val != 0)
1050 return ret_val;
1051 ret_val = security_secctx_to_secid(
1052 nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1053 nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
1054 &secid);
1055 if (ret_val != 0)
1056 return ret_val;
1057
1058 return netlbl_unlhsh_add(&init_net,
1059 NULL, addr, mask, addr_len, secid,
1060 &audit_info);
1061 }
1062
1063 /**
1064 * netlbl_unlabel_staticremove - Handle a STATICREMOVE message
1065 * @skb: the NETLINK buffer
1066 * @info: the Generic NETLINK info block
1067 *
1068 * Description:
1069 * Process a user generated STATICREMOVE message and remove the specified
1070 * unlabeled connection entry. Returns zero on success, negative values on
1071 * failure.
1072 *
1073 */
netlbl_unlabel_staticremove(struct sk_buff * skb,struct genl_info * info)1074 static int netlbl_unlabel_staticremove(struct sk_buff *skb,
1075 struct genl_info *info)
1076 {
1077 int ret_val;
1078 char *dev_name;
1079 void *addr;
1080 void *mask;
1081 u32 addr_len;
1082 struct netlbl_audit audit_info;
1083
1084 /* See the note in netlbl_unlabel_staticadd() about not allowing both
1085 * IPv4 and IPv6 in the same entry. */
1086 if (!info->attrs[NLBL_UNLABEL_A_IFACE] ||
1087 !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1088 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1089 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1090 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1091 return -EINVAL;
1092
1093 netlbl_netlink_auditinfo(skb, &audit_info);
1094
1095 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1096 if (ret_val != 0)
1097 return ret_val;
1098 dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]);
1099
1100 return netlbl_unlhsh_remove(&init_net,
1101 dev_name, addr, mask, addr_len,
1102 &audit_info);
1103 }
1104
1105 /**
1106 * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message
1107 * @skb: the NETLINK buffer
1108 * @info: the Generic NETLINK info block
1109 *
1110 * Description:
1111 * Process a user generated STATICREMOVEDEF message and remove the default
1112 * unlabeled connection entry. Returns zero on success, negative values on
1113 * failure.
1114 *
1115 */
netlbl_unlabel_staticremovedef(struct sk_buff * skb,struct genl_info * info)1116 static int netlbl_unlabel_staticremovedef(struct sk_buff *skb,
1117 struct genl_info *info)
1118 {
1119 int ret_val;
1120 void *addr;
1121 void *mask;
1122 u32 addr_len;
1123 struct netlbl_audit audit_info;
1124
1125 /* See the note in netlbl_unlabel_staticadd() about not allowing both
1126 * IPv4 and IPv6 in the same entry. */
1127 if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] ||
1128 !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^
1129 (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] ||
1130 !info->attrs[NLBL_UNLABEL_A_IPV6MASK])))
1131 return -EINVAL;
1132
1133 netlbl_netlink_auditinfo(skb, &audit_info);
1134
1135 ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len);
1136 if (ret_val != 0)
1137 return ret_val;
1138
1139 return netlbl_unlhsh_remove(&init_net,
1140 NULL, addr, mask, addr_len,
1141 &audit_info);
1142 }
1143
1144
1145 /**
1146 * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF]
1147 * @cmd: command/message
1148 * @iface: the interface entry
1149 * @addr4: the IPv4 address entry
1150 * @addr6: the IPv6 address entry
1151 * @arg: the netlbl_unlhsh_walk_arg structure
1152 *
1153 * Description:
1154 * This function is designed to be used to generate a response for a
1155 * STATICLIST or STATICLISTDEF message. When called either @addr4 or @addr6
1156 * can be specified, not both, the other unspecified entry should be set to
1157 * NULL by the caller. Returns the size of the message on success, negative
1158 * values on failure.
1159 *
1160 */
netlbl_unlabel_staticlist_gen(u32 cmd,const struct netlbl_unlhsh_iface * iface,const struct netlbl_unlhsh_addr4 * addr4,const struct netlbl_unlhsh_addr6 * addr6,void * arg)1161 static int netlbl_unlabel_staticlist_gen(u32 cmd,
1162 const struct netlbl_unlhsh_iface *iface,
1163 const struct netlbl_unlhsh_addr4 *addr4,
1164 const struct netlbl_unlhsh_addr6 *addr6,
1165 void *arg)
1166 {
1167 int ret_val = -ENOMEM;
1168 struct netlbl_unlhsh_walk_arg *cb_arg = arg;
1169 struct net_device *dev;
1170 void *data;
1171 u32 secid;
1172 char *secctx;
1173 u32 secctx_len;
1174
1175 data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
1176 cb_arg->seq, &netlbl_unlabel_gnl_family,
1177 NLM_F_MULTI, cmd);
1178 if (data == NULL)
1179 goto list_cb_failure;
1180
1181 if (iface->ifindex > 0) {
1182 dev = dev_get_by_index(&init_net, iface->ifindex);
1183 if (!dev) {
1184 ret_val = -ENODEV;
1185 goto list_cb_failure;
1186 }
1187 ret_val = nla_put_string(cb_arg->skb,
1188 NLBL_UNLABEL_A_IFACE, dev->name);
1189 dev_put(dev);
1190 if (ret_val != 0)
1191 goto list_cb_failure;
1192 }
1193
1194 if (addr4) {
1195 struct in_addr addr_struct;
1196
1197 addr_struct.s_addr = addr4->list.addr;
1198 ret_val = nla_put(cb_arg->skb,
1199 NLBL_UNLABEL_A_IPV4ADDR,
1200 sizeof(struct in_addr),
1201 &addr_struct);
1202 if (ret_val != 0)
1203 goto list_cb_failure;
1204
1205 addr_struct.s_addr = addr4->list.mask;
1206 ret_val = nla_put(cb_arg->skb,
1207 NLBL_UNLABEL_A_IPV4MASK,
1208 sizeof(struct in_addr),
1209 &addr_struct);
1210 if (ret_val != 0)
1211 goto list_cb_failure;
1212
1213 secid = addr4->secid;
1214 } else {
1215 ret_val = nla_put(cb_arg->skb,
1216 NLBL_UNLABEL_A_IPV6ADDR,
1217 sizeof(struct in6_addr),
1218 &addr6->list.addr);
1219 if (ret_val != 0)
1220 goto list_cb_failure;
1221
1222 ret_val = nla_put(cb_arg->skb,
1223 NLBL_UNLABEL_A_IPV6MASK,
1224 sizeof(struct in6_addr),
1225 &addr6->list.mask);
1226 if (ret_val != 0)
1227 goto list_cb_failure;
1228
1229 secid = addr6->secid;
1230 }
1231
1232 ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
1233 if (ret_val != 0)
1234 goto list_cb_failure;
1235 ret_val = nla_put(cb_arg->skb,
1236 NLBL_UNLABEL_A_SECCTX,
1237 secctx_len,
1238 secctx);
1239 security_release_secctx(secctx, secctx_len);
1240 if (ret_val != 0)
1241 goto list_cb_failure;
1242
1243 cb_arg->seq++;
1244 return genlmsg_end(cb_arg->skb, data);
1245
1246 list_cb_failure:
1247 genlmsg_cancel(cb_arg->skb, data);
1248 return ret_val;
1249 }
1250
1251 /**
1252 * netlbl_unlabel_staticlist - Handle a STATICLIST message
1253 * @skb: the NETLINK buffer
1254 * @cb: the NETLINK callback
1255 *
1256 * Description:
1257 * Process a user generated STATICLIST message and dump the unlabeled
1258 * connection hash table in a form suitable for use in a kernel generated
1259 * STATICLIST message. Returns the length of @skb.
1260 *
1261 */
netlbl_unlabel_staticlist(struct sk_buff * skb,struct netlink_callback * cb)1262 static int netlbl_unlabel_staticlist(struct sk_buff *skb,
1263 struct netlink_callback *cb)
1264 {
1265 struct netlbl_unlhsh_walk_arg cb_arg;
1266 u32 skip_bkt = cb->args[0];
1267 u32 skip_chain = cb->args[1];
1268 u32 skip_addr4 = cb->args[2];
1269 u32 skip_addr6 = cb->args[3];
1270 u32 iter_bkt;
1271 u32 iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0;
1272 struct netlbl_unlhsh_iface *iface;
1273 struct list_head *iter_list;
1274 struct netlbl_af4list *addr4;
1275 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1276 struct netlbl_af6list *addr6;
1277 #endif
1278
1279 cb_arg.nl_cb = cb;
1280 cb_arg.skb = skb;
1281 cb_arg.seq = cb->nlh->nlmsg_seq;
1282
1283 rcu_read_lock();
1284 for (iter_bkt = skip_bkt;
1285 iter_bkt < rcu_dereference(netlbl_unlhsh)->size;
1286 iter_bkt++, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0) {
1287 iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt];
1288 list_for_each_entry_rcu(iface, iter_list, list) {
1289 if (!iface->valid ||
1290 iter_chain++ < skip_chain)
1291 continue;
1292 netlbl_af4list_foreach_rcu(addr4,
1293 &iface->addr4_list) {
1294 if (iter_addr4++ < skip_addr4)
1295 continue;
1296 if (netlbl_unlabel_staticlist_gen(
1297 NLBL_UNLABEL_C_STATICLIST,
1298 iface,
1299 netlbl_unlhsh_addr4_entry(addr4),
1300 NULL,
1301 &cb_arg) < 0) {
1302 iter_addr4--;
1303 iter_chain--;
1304 goto unlabel_staticlist_return;
1305 }
1306 }
1307 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1308 netlbl_af6list_foreach_rcu(addr6,
1309 &iface->addr6_list) {
1310 if (iter_addr6++ < skip_addr6)
1311 continue;
1312 if (netlbl_unlabel_staticlist_gen(
1313 NLBL_UNLABEL_C_STATICLIST,
1314 iface,
1315 NULL,
1316 netlbl_unlhsh_addr6_entry(addr6),
1317 &cb_arg) < 0) {
1318 iter_addr6--;
1319 iter_chain--;
1320 goto unlabel_staticlist_return;
1321 }
1322 }
1323 #endif /* IPv6 */
1324 }
1325 }
1326
1327 unlabel_staticlist_return:
1328 rcu_read_unlock();
1329 cb->args[0] = skip_bkt;
1330 cb->args[1] = skip_chain;
1331 cb->args[2] = skip_addr4;
1332 cb->args[3] = skip_addr6;
1333 return skb->len;
1334 }
1335
1336 /**
1337 * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message
1338 * @skb: the NETLINK buffer
1339 * @cb: the NETLINK callback
1340 *
1341 * Description:
1342 * Process a user generated STATICLISTDEF message and dump the default
1343 * unlabeled connection entry in a form suitable for use in a kernel generated
1344 * STATICLISTDEF message. Returns the length of @skb.
1345 *
1346 */
netlbl_unlabel_staticlistdef(struct sk_buff * skb,struct netlink_callback * cb)1347 static int netlbl_unlabel_staticlistdef(struct sk_buff *skb,
1348 struct netlink_callback *cb)
1349 {
1350 struct netlbl_unlhsh_walk_arg cb_arg;
1351 struct netlbl_unlhsh_iface *iface;
1352 u32 skip_addr4 = cb->args[0];
1353 u32 skip_addr6 = cb->args[1];
1354 u32 iter_addr4 = 0;
1355 struct netlbl_af4list *addr4;
1356 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1357 u32 iter_addr6 = 0;
1358 struct netlbl_af6list *addr6;
1359 #endif
1360
1361 cb_arg.nl_cb = cb;
1362 cb_arg.skb = skb;
1363 cb_arg.seq = cb->nlh->nlmsg_seq;
1364
1365 rcu_read_lock();
1366 iface = rcu_dereference(netlbl_unlhsh_def);
1367 if (iface == NULL || !iface->valid)
1368 goto unlabel_staticlistdef_return;
1369
1370 netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) {
1371 if (iter_addr4++ < skip_addr4)
1372 continue;
1373 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1374 iface,
1375 netlbl_unlhsh_addr4_entry(addr4),
1376 NULL,
1377 &cb_arg) < 0) {
1378 iter_addr4--;
1379 goto unlabel_staticlistdef_return;
1380 }
1381 }
1382 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1383 netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) {
1384 if (iter_addr6++ < skip_addr6)
1385 continue;
1386 if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF,
1387 iface,
1388 NULL,
1389 netlbl_unlhsh_addr6_entry(addr6),
1390 &cb_arg) < 0) {
1391 iter_addr6--;
1392 goto unlabel_staticlistdef_return;
1393 }
1394 }
1395 #endif /* IPv6 */
1396
1397 unlabel_staticlistdef_return:
1398 rcu_read_unlock();
1399 cb->args[0] = skip_addr4;
1400 cb->args[1] = skip_addr6;
1401 return skb->len;
1402 }
1403
1404 /*
1405 * NetLabel Generic NETLINK Command Definitions
1406 */
1407
1408 static struct genl_ops netlbl_unlabel_genl_ops[] = {
1409 {
1410 .cmd = NLBL_UNLABEL_C_STATICADD,
1411 .flags = GENL_ADMIN_PERM,
1412 .policy = netlbl_unlabel_genl_policy,
1413 .doit = netlbl_unlabel_staticadd,
1414 .dumpit = NULL,
1415 },
1416 {
1417 .cmd = NLBL_UNLABEL_C_STATICREMOVE,
1418 .flags = GENL_ADMIN_PERM,
1419 .policy = netlbl_unlabel_genl_policy,
1420 .doit = netlbl_unlabel_staticremove,
1421 .dumpit = NULL,
1422 },
1423 {
1424 .cmd = NLBL_UNLABEL_C_STATICLIST,
1425 .flags = 0,
1426 .policy = netlbl_unlabel_genl_policy,
1427 .doit = NULL,
1428 .dumpit = netlbl_unlabel_staticlist,
1429 },
1430 {
1431 .cmd = NLBL_UNLABEL_C_STATICADDDEF,
1432 .flags = GENL_ADMIN_PERM,
1433 .policy = netlbl_unlabel_genl_policy,
1434 .doit = netlbl_unlabel_staticadddef,
1435 .dumpit = NULL,
1436 },
1437 {
1438 .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF,
1439 .flags = GENL_ADMIN_PERM,
1440 .policy = netlbl_unlabel_genl_policy,
1441 .doit = netlbl_unlabel_staticremovedef,
1442 .dumpit = NULL,
1443 },
1444 {
1445 .cmd = NLBL_UNLABEL_C_STATICLISTDEF,
1446 .flags = 0,
1447 .policy = netlbl_unlabel_genl_policy,
1448 .doit = NULL,
1449 .dumpit = netlbl_unlabel_staticlistdef,
1450 },
1451 {
1452 .cmd = NLBL_UNLABEL_C_ACCEPT,
1453 .flags = GENL_ADMIN_PERM,
1454 .policy = netlbl_unlabel_genl_policy,
1455 .doit = netlbl_unlabel_accept,
1456 .dumpit = NULL,
1457 },
1458 {
1459 .cmd = NLBL_UNLABEL_C_LIST,
1460 .flags = 0,
1461 .policy = netlbl_unlabel_genl_policy,
1462 .doit = netlbl_unlabel_list,
1463 .dumpit = NULL,
1464 },
1465 };
1466
1467 /*
1468 * NetLabel Generic NETLINK Protocol Functions
1469 */
1470
1471 /**
1472 * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
1473 *
1474 * Description:
1475 * Register the unlabeled packet NetLabel component with the Generic NETLINK
1476 * mechanism. Returns zero on success, negative values on failure.
1477 *
1478 */
netlbl_unlabel_genl_init(void)1479 int __init netlbl_unlabel_genl_init(void)
1480 {
1481 int ret_val, i;
1482
1483 ret_val = genl_register_family(&netlbl_unlabel_gnl_family);
1484 if (ret_val != 0)
1485 return ret_val;
1486
1487 for (i = 0; i < ARRAY_SIZE(netlbl_unlabel_genl_ops); i++) {
1488 ret_val = genl_register_ops(&netlbl_unlabel_gnl_family,
1489 &netlbl_unlabel_genl_ops[i]);
1490 if (ret_val != 0)
1491 return ret_val;
1492 }
1493
1494 return 0;
1495 }
1496
1497 /*
1498 * NetLabel KAPI Hooks
1499 */
1500
1501 static struct notifier_block netlbl_unlhsh_netdev_notifier = {
1502 .notifier_call = netlbl_unlhsh_netdev_handler,
1503 };
1504
1505 /**
1506 * netlbl_unlabel_init - Initialize the unlabeled connection hash table
1507 * @size: the number of bits to use for the hash buckets
1508 *
1509 * Description:
1510 * Initializes the unlabeled connection hash table and registers a network
1511 * device notification handler. This function should only be called by the
1512 * NetLabel subsystem itself during initialization. Returns zero on success,
1513 * non-zero values on error.
1514 *
1515 */
netlbl_unlabel_init(u32 size)1516 int __init netlbl_unlabel_init(u32 size)
1517 {
1518 u32 iter;
1519 struct netlbl_unlhsh_tbl *hsh_tbl;
1520
1521 if (size == 0)
1522 return -EINVAL;
1523
1524 hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
1525 if (hsh_tbl == NULL)
1526 return -ENOMEM;
1527 hsh_tbl->size = 1 << size;
1528 hsh_tbl->tbl = kcalloc(hsh_tbl->size,
1529 sizeof(struct list_head),
1530 GFP_KERNEL);
1531 if (hsh_tbl->tbl == NULL) {
1532 kfree(hsh_tbl);
1533 return -ENOMEM;
1534 }
1535 for (iter = 0; iter < hsh_tbl->size; iter++)
1536 INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
1537
1538 rcu_read_lock();
1539 spin_lock(&netlbl_unlhsh_lock);
1540 rcu_assign_pointer(netlbl_unlhsh, hsh_tbl);
1541 spin_unlock(&netlbl_unlhsh_lock);
1542 rcu_read_unlock();
1543
1544 register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier);
1545
1546 return 0;
1547 }
1548
1549 /**
1550 * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
1551 * @skb: the packet
1552 * @family: protocol family
1553 * @secattr: the security attributes
1554 *
1555 * Description:
1556 * Determine the security attributes, if any, for an unlabled packet and return
1557 * them in @secattr. Returns zero on success and negative values on failure.
1558 *
1559 */
netlbl_unlabel_getattr(const struct sk_buff * skb,u16 family,struct netlbl_lsm_secattr * secattr)1560 int netlbl_unlabel_getattr(const struct sk_buff *skb,
1561 u16 family,
1562 struct netlbl_lsm_secattr *secattr)
1563 {
1564 struct netlbl_unlhsh_iface *iface;
1565
1566 rcu_read_lock();
1567 iface = netlbl_unlhsh_search_iface_def(skb->iif);
1568 if (iface == NULL)
1569 goto unlabel_getattr_nolabel;
1570 switch (family) {
1571 case PF_INET: {
1572 struct iphdr *hdr4;
1573 struct netlbl_af4list *addr4;
1574
1575 hdr4 = ip_hdr(skb);
1576 addr4 = netlbl_af4list_search(hdr4->saddr,
1577 &iface->addr4_list);
1578 if (addr4 == NULL)
1579 goto unlabel_getattr_nolabel;
1580 secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
1581 break;
1582 }
1583 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1584 case PF_INET6: {
1585 struct ipv6hdr *hdr6;
1586 struct netlbl_af6list *addr6;
1587
1588 hdr6 = ipv6_hdr(skb);
1589 addr6 = netlbl_af6list_search(&hdr6->saddr,
1590 &iface->addr6_list);
1591 if (addr6 == NULL)
1592 goto unlabel_getattr_nolabel;
1593 secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
1594 break;
1595 }
1596 #endif /* IPv6 */
1597 default:
1598 goto unlabel_getattr_nolabel;
1599 }
1600 rcu_read_unlock();
1601
1602 secattr->flags |= NETLBL_SECATTR_SECID;
1603 secattr->type = NETLBL_NLTYPE_UNLABELED;
1604 return 0;
1605
1606 unlabel_getattr_nolabel:
1607 rcu_read_unlock();
1608 if (netlabel_unlabel_acceptflg == 0)
1609 return -ENOMSG;
1610 secattr->type = NETLBL_NLTYPE_UNLABELED;
1611 return 0;
1612 }
1613
1614 /**
1615 * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
1616 *
1617 * Description:
1618 * Set the default NetLabel configuration to allow incoming unlabeled packets
1619 * and to send unlabeled network traffic by default.
1620 *
1621 */
netlbl_unlabel_defconf(void)1622 int __init netlbl_unlabel_defconf(void)
1623 {
1624 int ret_val;
1625 struct netlbl_dom_map *entry;
1626 struct netlbl_audit audit_info;
1627
1628 /* Only the kernel is allowed to call this function and the only time
1629 * it is called is at bootup before the audit subsystem is reporting
1630 * messages so don't worry to much about these values. */
1631 security_task_getsecid(current, &audit_info.secid);
1632 audit_info.loginuid = 0;
1633 audit_info.sessionid = 0;
1634
1635 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1636 if (entry == NULL)
1637 return -ENOMEM;
1638 entry->type = NETLBL_NLTYPE_UNLABELED;
1639 ret_val = netlbl_domhsh_add_default(entry, &audit_info);
1640 if (ret_val != 0)
1641 return ret_val;
1642
1643 netlbl_unlabel_acceptflg_set(1, &audit_info);
1644
1645 return 0;
1646 }
1647