1/*
2 * lib/route/neigh.c	Neighbours
3 *
4 *	This library is free software; you can redistribute it and/or
5 *	modify it under the terms of the GNU Lesser General Public
6 *	License as published by the Free Software Foundation version 2.1
7 *	of the License.
8 *
9 * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch>
10 */
11
12/**
13 * @ingroup rtnl
14 * @defgroup neigh Neighbours
15 * @brief
16 *
17 * The neighbour table establishes bindings between protocol addresses and
18 * link layer addresses for hosts sharing the same physical link. This
19 * module allows you to access and manipulate the content of these tables.
20 *
21 * @par Neighbour States
22 * @code
23 * NUD_INCOMPLETE
24 * NUD_REACHABLE
25 * NUD_STALE
26 * NUD_DELAY
27 * NUD_PROBE
28 * NUD_FAILED
29 * NUD_NOARP
30 * NUD_PERMANENT
31 * @endcode
32 *
33 * @par Neighbour Flags
34 * @code
35 * NTF_PROXY
36 * NTF_ROUTER
37 * @endcode
38 *
39 * @par Neighbour Identification
40 * A neighbour is uniquely identified by the attributes listed below, whenever
41 * you refer to an existing neighbour all of the attributes must be set.
42 * Neighbours from caches automatically have all required attributes set.
43 *   - interface index (rtnl_neigh_set_ifindex())
44 *   - destination address (rtnl_neigh_set_dst())
45 *
46 * @par Changeable Attributes
47 * \anchor neigh_changeable
48 *  - state (rtnl_neigh_set_state())
49 *  - link layer address (rtnl_neigh_set_lladdr())
50 *
51 * @par Required Caches for Dumping
52 * In order to dump neighbour attributes you must provide the following
53 * caches via nl_cache_provide()
54 *  - link cache holding all links
55 *
56 * @par TODO
57 *   - Document proxy settings
58 *   - Document states and their influence
59 *
60 * @par 1) Retrieving information about configured neighbours
61 * @code
62 * // The first step is to retrieve a list of all available neighbour within
63 * // the kernel and put them into a cache.
64 * struct nl_cache *cache = rtnl_neigh_alloc_cache(sk);
65 *
66 * // Neighbours can then be looked up by the interface and destination
67 * // address:
68 * struct rtnl_neigh *neigh = rtnl_neigh_get(cache, ifindex, dst_addr);
69 *
70 * // After successful usage, the object must be given back to the cache
71 * rtnl_neigh_put(neigh);
72 * @endcode
73 *
74 * @par 2) Adding new neighbours
75 * @code
76 * // Allocate an empty neighbour handle to be filled out with the attributes
77 * // of the new neighbour.
78 * struct rtnl_neigh *neigh = rtnl_neigh_alloc();
79 *
80 * // Fill out the attributes of the new neighbour
81 * rtnl_neigh_set_ifindex(neigh, ifindex);
82 * rtnl_neigh_set_dst(neigh, dst_addr);
83 * rtnl_neigh_set_state(neigh, rtnl_neigh_str2state("permanent"));
84 *
85 * // Build the netlink message and send it to the kernel, the operation will
86 * // block until the operation has been completed. Alternatively the required
87 * // netlink message can be built using rtnl_neigh_build_add_request()
88 * // to be sent out using nl_send_auto_complete().
89 * rtnl_neigh_add(sk, neigh, NLM_F_CREATE);
90 *
91 * // Free the memory
92 * rtnl_neigh_put(neigh);
93 * @endcode
94 *
95 * @par 3) Deleting an existing neighbour
96 * @code
97 * // Allocate an empty neighbour object to be filled out with the attributes
98 * // matching the neighbour to be deleted. Alternatively a fully equipped
99 * // neighbour object out of a cache can be used instead.
100 * struct rtnl_neigh *neigh = rtnl_neigh_alloc();
101 *
102 * // Neighbours are uniquely identified by their interface index and
103 * // destination address, you may fill out other attributes but they
104 * // will have no influence.
105 * rtnl_neigh_set_ifindex(neigh, ifindex);
106 * rtnl_neigh_set_dst(neigh, dst_addr);
107 *
108 * // Build the netlink message and send it to the kernel, the operation will
109 * // block until the operation has been completed. Alternatively the required
110 * // netlink message can be built using rtnl_neigh_build_delete_request()
111 * // to be sent out using nl_send_auto_complete().
112 * rtnl_neigh_delete(sk, neigh, 0);
113 *
114 * // Free the memory
115 * rtnl_neigh_put(neigh);
116 * @endcode
117 *
118 * @par 4) Changing neighbour attributes
119 * @code
120 * // Allocate an empty neighbour object to be filled out with the attributes
121 * // matching the neighbour to be changed and the new parameters. Alternatively
122 * // a fully equipped modified neighbour object out of a cache can be used.
123 * struct rtnl_neigh *neigh = rtnl_neigh_alloc();
124 *
125 * // Identify the neighbour to be changed by its interface index and
126 * // destination address
127 * rtnl_neigh_set_ifindex(neigh, ifindex);
128 * rtnl_neigh_set_dst(neigh, dst_addr);
129 *
130 * // The link layer address may be modified, if so it is wise to change
131 * // its state to "permanent" in order to avoid having it overwritten.
132 * rtnl_neigh_set_lladdr(neigh, lladdr);
133 *
134 * // Secondly the state can be modified allowing normal neighbours to be
135 * // converted into permanent entries or to manually confirm a neighbour.
136 * rtnl_neigh_set_state(neigh, state);
137 *
138 * // Build the netlink message and send it to the kernel, the operation will
139 * // block until the operation has been completed. Alternatively the required
140 * // netlink message can be built using rtnl_neigh_build_change_request()
141 * // to be sent out using nl_send_auto_complete().
142 * rtnl_neigh_add(sk, neigh, NLM_F_REPLACE);
143 *
144 * // Free the memory
145 * rtnl_neigh_put(neigh);
146 * @endcode
147 * @{
148 */
149
150#include <netlink-local.h>
151#include <netlink/netlink.h>
152#include <netlink/utils.h>
153#include <netlink/route/rtnl.h>
154#include <netlink/route/neighbour.h>
155#include <netlink/route/link.h>
156
157/** @cond SKIP */
158#define NEIGH_ATTR_FLAGS        0x01
159#define NEIGH_ATTR_STATE        0x02
160#define NEIGH_ATTR_LLADDR       0x04
161#define NEIGH_ATTR_DST          0x08
162#define NEIGH_ATTR_CACHEINFO    0x10
163#define NEIGH_ATTR_IFINDEX      0x20
164#define NEIGH_ATTR_FAMILY       0x40
165#define NEIGH_ATTR_TYPE         0x80
166#define NEIGH_ATTR_PROBES       0x100
167
168static struct nl_cache_ops rtnl_neigh_ops;
169static struct nl_object_ops neigh_obj_ops;
170/** @endcond */
171
172static void neigh_free_data(struct nl_object *c)
173{
174	struct rtnl_neigh *neigh = nl_object_priv(c);
175
176	if (!neigh)
177		return;
178
179	nl_addr_put(neigh->n_lladdr);
180	nl_addr_put(neigh->n_dst);
181}
182
183static int neigh_clone(struct nl_object *_dst, struct nl_object *_src)
184{
185	struct rtnl_neigh *dst = nl_object_priv(_dst);
186	struct rtnl_neigh *src = nl_object_priv(_src);
187
188	if (src->n_lladdr)
189		if (!(dst->n_lladdr = nl_addr_clone(src->n_lladdr)))
190			return -NLE_NOMEM;
191
192	if (src->n_dst)
193		if (!(dst->n_dst = nl_addr_clone(src->n_dst)))
194			return -NLE_NOMEM;
195
196	return 0;
197}
198
199static int neigh_compare(struct nl_object *_a, struct nl_object *_b,
200			uint32_t attrs, int flags)
201{
202	struct rtnl_neigh *a = (struct rtnl_neigh *) _a;
203	struct rtnl_neigh *b = (struct rtnl_neigh *) _b;
204	int diff = 0;
205
206#define NEIGH_DIFF(ATTR, EXPR) ATTR_DIFF(attrs, NEIGH_ATTR_##ATTR, a, b, EXPR)
207
208	diff |= NEIGH_DIFF(IFINDEX,	a->n_ifindex != b->n_ifindex);
209	diff |= NEIGH_DIFF(FAMILY,	a->n_family != b->n_family);
210	diff |= NEIGH_DIFF(TYPE,	a->n_type != b->n_type);
211	diff |= NEIGH_DIFF(LLADDR,	nl_addr_cmp(a->n_lladdr, b->n_lladdr));
212	diff |= NEIGH_DIFF(DST,		nl_addr_cmp(a->n_dst, b->n_dst));
213
214	if (flags & LOOSE_COMPARISON) {
215		diff |= NEIGH_DIFF(STATE,
216				  (a->n_state ^ b->n_state) & b->n_state_mask);
217		diff |= NEIGH_DIFF(FLAGS,
218				  (a->n_flags ^ b->n_flags) & b->n_flag_mask);
219	} else {
220		diff |= NEIGH_DIFF(STATE, a->n_state != b->n_state);
221		diff |= NEIGH_DIFF(FLAGS, a->n_flags != b->n_flags);
222	}
223
224#undef NEIGH_DIFF
225
226	return diff;
227}
228
229static struct trans_tbl neigh_attrs[] = {
230	__ADD(NEIGH_ATTR_FLAGS, flags)
231	__ADD(NEIGH_ATTR_STATE, state)
232	__ADD(NEIGH_ATTR_LLADDR, lladdr)
233	__ADD(NEIGH_ATTR_DST, dst)
234	__ADD(NEIGH_ATTR_CACHEINFO, cacheinfo)
235	__ADD(NEIGH_ATTR_IFINDEX, ifindex)
236	__ADD(NEIGH_ATTR_FAMILY, family)
237	__ADD(NEIGH_ATTR_TYPE, type)
238	__ADD(NEIGH_ATTR_PROBES, probes)
239};
240
241static char *neigh_attrs2str(int attrs, char *buf, size_t len)
242{
243	return __flags2str(attrs, buf, len, neigh_attrs,
244			   ARRAY_SIZE(neigh_attrs));
245}
246
247static struct nla_policy neigh_policy[NDA_MAX+1] = {
248	[NDA_CACHEINFO]	= { .minlen = sizeof(struct nda_cacheinfo) },
249	[NDA_PROBES]	= { .type = NLA_U32 },
250};
251
252static int neigh_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
253			    struct nlmsghdr *n, struct nl_parser_param *pp)
254{
255	struct rtnl_neigh *neigh;
256	struct nlattr *tb[NDA_MAX + 1];
257	struct ndmsg *nm;
258	int err;
259
260	neigh = rtnl_neigh_alloc();
261	if (!neigh) {
262		err = -NLE_NOMEM;
263		goto errout;
264	}
265
266	neigh->ce_msgtype = n->nlmsg_type;
267	nm = nlmsg_data(n);
268
269	err = nlmsg_parse(n, sizeof(*nm), tb, NDA_MAX, neigh_policy);
270	if (err < 0)
271		goto errout;
272
273	neigh->n_family  = nm->ndm_family;
274	neigh->n_ifindex = nm->ndm_ifindex;
275	neigh->n_state   = nm->ndm_state;
276	neigh->n_flags   = nm->ndm_flags;
277	neigh->n_type    = nm->ndm_type;
278
279	neigh->ce_mask |= (NEIGH_ATTR_FAMILY | NEIGH_ATTR_IFINDEX |
280			   NEIGH_ATTR_STATE | NEIGH_ATTR_FLAGS |
281			   NEIGH_ATTR_TYPE);
282
283	if (tb[NDA_LLADDR]) {
284		neigh->n_lladdr = nl_addr_alloc_attr(tb[NDA_LLADDR], AF_UNSPEC);
285		if (!neigh->n_lladdr) {
286			err = -NLE_NOMEM;
287			goto errout;
288		}
289		nl_addr_set_family(neigh->n_lladdr,
290				   nl_addr_guess_family(neigh->n_lladdr));
291		neigh->ce_mask |= NEIGH_ATTR_LLADDR;
292	}
293
294	if (tb[NDA_DST]) {
295		neigh->n_dst = nl_addr_alloc_attr(tb[NDA_DST], neigh->n_family);
296		if (!neigh->n_dst) {
297			err = -NLE_NOMEM;
298			goto errout;
299		}
300		neigh->ce_mask |= NEIGH_ATTR_DST;
301	}
302
303	if (tb[NDA_CACHEINFO]) {
304		struct nda_cacheinfo *ci = nla_data(tb[NDA_CACHEINFO]);
305
306		neigh->n_cacheinfo.nci_confirmed = ci->ndm_confirmed;
307		neigh->n_cacheinfo.nci_used = ci->ndm_used;
308		neigh->n_cacheinfo.nci_updated = ci->ndm_updated;
309		neigh->n_cacheinfo.nci_refcnt = ci->ndm_refcnt;
310
311		neigh->ce_mask |= NEIGH_ATTR_CACHEINFO;
312	}
313
314	if (tb[NDA_PROBES]) {
315		neigh->n_probes = nla_get_u32(tb[NDA_PROBES]);
316		neigh->ce_mask |= NEIGH_ATTR_PROBES;
317	}
318
319	err = pp->pp_cb((struct nl_object *) neigh, pp);
320errout:
321	rtnl_neigh_put(neigh);
322	return err;
323}
324
325static int neigh_request_update(struct nl_cache *c, struct nl_sock *h)
326{
327	return nl_rtgen_request(h, RTM_GETNEIGH, AF_UNSPEC, NLM_F_DUMP);
328}
329
330
331static void neigh_dump_line(struct nl_object *a, struct nl_dump_params *p)
332{
333	char dst[INET6_ADDRSTRLEN+5], lladdr[INET6_ADDRSTRLEN+5];
334	struct rtnl_neigh *n = (struct rtnl_neigh *) a;
335	struct nl_cache *link_cache;
336	char state[128], flags[64];
337
338	link_cache = nl_cache_mngt_require("route/link");
339
340	nl_dump_line(p, "%s ", nl_addr2str(n->n_dst, dst, sizeof(dst)));
341
342	if (link_cache)
343		nl_dump(p, "dev %s ",
344			rtnl_link_i2name(link_cache, n->n_ifindex,
345					 state, sizeof(state)));
346	else
347		nl_dump(p, "dev %d ", n->n_ifindex);
348
349	if (n->ce_mask & NEIGH_ATTR_LLADDR)
350		nl_dump(p, "lladdr %s ",
351			nl_addr2str(n->n_lladdr, lladdr, sizeof(lladdr)));
352
353	rtnl_neigh_state2str(n->n_state, state, sizeof(state));
354	rtnl_neigh_flags2str(n->n_flags, flags, sizeof(flags));
355
356	if (state[0])
357		nl_dump(p, "<%s", state);
358	if (flags[0])
359		nl_dump(p, "%s%s", state[0] ? "," : "<", flags);
360	if (state[0] || flags[0])
361		nl_dump(p, ">");
362	nl_dump(p, "\n");
363}
364
365static void neigh_dump_details(struct nl_object *a, struct nl_dump_params *p)
366{
367	char rtn_type[32];
368	struct rtnl_neigh *n = (struct rtnl_neigh *) a;
369	int hz = nl_get_hz();
370
371	neigh_dump_line(a, p);
372
373	nl_dump_line(p, "    refcnt %u type %s confirmed %u used "
374				"%u updated %u\n",
375		n->n_cacheinfo.nci_refcnt,
376		nl_rtntype2str(n->n_type, rtn_type, sizeof(rtn_type)),
377		n->n_cacheinfo.nci_confirmed/hz,
378		n->n_cacheinfo.nci_used/hz, n->n_cacheinfo.nci_updated/hz);
379}
380
381static void neigh_dump_stats(struct nl_object *a, struct nl_dump_params *p)
382{
383	neigh_dump_details(a, p);
384}
385
386static void neigh_dump_env(struct nl_object *obj, struct nl_dump_params *p)
387{
388	struct rtnl_neigh *neigh = (struct rtnl_neigh *) obj;
389	char buf[128];
390
391	nl_dump_line(p, "NEIGH_FAMILY=%s\n",
392		     nl_af2str(neigh->n_family, buf, sizeof(buf)));
393
394	if (neigh->ce_mask & NEIGH_ATTR_LLADDR)
395		nl_dump_line(p, "NEIGHT_LLADDR=%s\n",
396			     nl_addr2str(neigh->n_lladdr, buf, sizeof(buf)));
397
398	if (neigh->ce_mask & NEIGH_ATTR_DST)
399		nl_dump_line(p, "NEIGH_DST=%s\n",
400			     nl_addr2str(neigh->n_dst, buf, sizeof(buf)));
401
402	if (neigh->ce_mask & NEIGH_ATTR_IFINDEX) {
403		struct nl_cache *link_cache;
404
405		nl_dump_line(p, "NEIGH_IFINDEX=%u\n", neigh->n_ifindex);
406
407		link_cache = nl_cache_mngt_require("route/link");
408		if (link_cache)
409			nl_dump_line(p, "NEIGH_IFNAME=%s\n",
410				     rtnl_link_i2name(link_cache,
411						      neigh->n_ifindex,
412						      buf, sizeof(buf)));
413	}
414
415	if (neigh->ce_mask & NEIGH_ATTR_PROBES)
416		nl_dump_line(p, "NEIGH_PROBES=%u\n", neigh->n_probes);
417
418	if (neigh->ce_mask & NEIGH_ATTR_TYPE)
419		nl_dump_line(p, "NEIGH_TYPE=%s\n",
420			     nl_rtntype2str(neigh->n_type, buf, sizeof(buf)));
421
422	rtnl_neigh_flags2str(neigh->n_flags, buf, sizeof(buf));
423	if (buf[0])
424		nl_dump_line(p, "NEIGH_FLAGS=%s\n", buf);
425
426	rtnl_neigh_state2str(neigh->n_state, buf, sizeof(buf));
427	if (buf[0])
428		nl_dump_line(p, "NEIGH_STATE=%s\n", buf);
429}
430
431/**
432 * @name Neighbour Object Allocation/Freeage
433 * @{
434 */
435
436struct rtnl_neigh *rtnl_neigh_alloc(void)
437{
438	return (struct rtnl_neigh *) nl_object_alloc(&neigh_obj_ops);
439}
440
441void rtnl_neigh_put(struct rtnl_neigh *neigh)
442{
443	nl_object_put((struct nl_object *) neigh);
444}
445
446/** @} */
447
448/**
449 * @name Neighbour Cache Managament
450 * @{
451 */
452
453/**
454 * Build a neighbour cache including all neighbours currently configured in the kernel.
455 * @arg sk		Netlink socket.
456 * @arg result		Pointer to store resulting cache.
457 *
458 * Allocates a new neighbour cache, initializes it properly and updates it
459 * to include all neighbours currently configured in the kernel.
460 *
461 * @return 0 on success or a negative error code.
462 */
463int rtnl_neigh_alloc_cache(struct nl_sock *sock, struct nl_cache **result)
464{
465	return nl_cache_alloc_and_fill(&rtnl_neigh_ops, sock, result);
466}
467
468/**
469 * Look up a neighbour by interface index and destination address
470 * @arg cache		neighbour cache
471 * @arg ifindex		interface index the neighbour is on
472 * @arg dst		destination address of the neighbour
473 * @return neighbour handle or NULL if no match was found.
474 */
475struct rtnl_neigh * rtnl_neigh_get(struct nl_cache *cache, int ifindex,
476				   struct nl_addr *dst)
477{
478	struct rtnl_neigh *neigh;
479
480	nl_list_for_each_entry(neigh, &cache->c_items, ce_list) {
481		if (neigh->n_ifindex == ifindex &&
482		    !nl_addr_cmp(neigh->n_dst, dst)) {
483			nl_object_get((struct nl_object *) neigh);
484			return neigh;
485		}
486	}
487
488	return NULL;
489}
490
491/** @} */
492
493/**
494 * @name Neighbour Addition
495 * @{
496 */
497
498static int build_neigh_msg(struct rtnl_neigh *tmpl, int cmd, int flags,
499			   struct nl_msg **result)
500{
501	struct nl_msg *msg;
502	struct ndmsg nhdr = {
503		.ndm_ifindex = tmpl->n_ifindex,
504		.ndm_state = NUD_PERMANENT,
505	};
506
507	if (!(tmpl->ce_mask & NEIGH_ATTR_DST))
508		return -NLE_MISSING_ATTR;
509
510	nhdr.ndm_family = nl_addr_get_family(tmpl->n_dst);
511
512	if (tmpl->ce_mask & NEIGH_ATTR_STATE)
513		nhdr.ndm_state = tmpl->n_state;
514
515	msg = nlmsg_alloc_simple(cmd, flags);
516	if (!msg)
517		return -NLE_NOMEM;
518
519	if (nlmsg_append(msg, &nhdr, sizeof(nhdr), NLMSG_ALIGNTO) < 0)
520		goto nla_put_failure;
521
522	NLA_PUT_ADDR(msg, NDA_DST, tmpl->n_dst);
523
524	if (tmpl->ce_mask & NEIGH_ATTR_LLADDR)
525		NLA_PUT_ADDR(msg, NDA_LLADDR, tmpl->n_lladdr);
526
527	*result = msg;
528	return 0;
529
530nla_put_failure:
531	nlmsg_free(msg);
532	return -NLE_MSGSIZE;
533}
534
535/**
536 * Build netlink request message to add a new neighbour
537 * @arg tmpl		template with data of new neighbour
538 * @arg flags		additional netlink message flags
539 * @arg result		Pointer to store resulting message.
540 *
541 * Builds a new netlink message requesting a addition of a new
542 * neighbour. The netlink message header isn't fully equipped with
543 * all relevant fields and must thus be sent out via nl_send_auto_complete()
544 * or supplemented as needed. \a tmpl must contain the attributes of the new
545 * neighbour set via \c rtnl_neigh_set_* functions.
546 *
547 * The following attributes must be set in the template:
548 *  - Interface index (rtnl_neigh_set_ifindex())
549 *  - State (rtnl_neigh_set_state())
550 *  - Destination address (rtnl_neigh_set_dst())
551 *  - Link layer address (rtnl_neigh_set_lladdr())
552 *
553 * @return 0 on success or a negative error code.
554 */
555int rtnl_neigh_build_add_request(struct rtnl_neigh *tmpl, int flags,
556				 struct nl_msg **result)
557{
558	return build_neigh_msg(tmpl, RTM_NEWNEIGH, flags, result);
559}
560
561/**
562 * Add a new neighbour
563 * @arg sk		Netlink socket.
564 * @arg tmpl		template with requested changes
565 * @arg flags		additional netlink message flags
566 *
567 * Builds a netlink message by calling rtnl_neigh_build_add_request(),
568 * sends the request to the kernel and waits for the next ACK to be
569 * received and thus blocks until the request has been fullfilled.
570 *
571 * The following attributes must be set in the template:
572 *  - Interface index (rtnl_neigh_set_ifindex())
573 *  - State (rtnl_neigh_set_state())
574 *  - Destination address (rtnl_neigh_set_dst())
575 *  - Link layer address (rtnl_neigh_set_lladdr())
576 *
577 * @return 0 on sucess or a negative error if an error occured.
578 */
579int rtnl_neigh_add(struct nl_sock *sk, struct rtnl_neigh *tmpl, int flags)
580{
581	int err;
582	struct nl_msg *msg;
583
584	if ((err = rtnl_neigh_build_add_request(tmpl, flags, &msg)) < 0)
585		return err;
586
587	err = nl_send_auto_complete(sk, msg);
588	nlmsg_free(msg);
589	if (err < 0)
590		return err;
591
592	return wait_for_ack(sk);
593}
594
595/** @} */
596
597/**
598 * @name Neighbour Deletion
599 * @{
600 */
601
602/**
603 * Build a netlink request message to delete a neighbour
604 * @arg neigh		neighbour to delete
605 * @arg flags		additional netlink message flags
606 * @arg result		Pointer to store resulting message.
607 *
608 * Builds a new netlink message requesting a deletion of a neighbour.
609 * The netlink message header isn't fully equipped with all relevant
610 * fields and must thus be sent out via nl_send_auto_complete()
611 * or supplemented as needed. \a neigh must point to an existing
612 * neighbour.
613 *
614 * @return 0 on success or a negative error code.
615 */
616int rtnl_neigh_build_delete_request(struct rtnl_neigh *neigh, int flags,
617				    struct nl_msg **result)
618{
619	return build_neigh_msg(neigh, RTM_DELNEIGH, flags, result);
620}
621
622/**
623 * Delete a neighbour
624 * @arg sk		Netlink socket.
625 * @arg neigh		neighbour to delete
626 * @arg flags		additional netlink message flags
627 *
628 * Builds a netlink message by calling rtnl_neigh_build_delete_request(),
629 * sends the request to the kernel and waits for the next ACK to be
630 * received and thus blocks until the request has been fullfilled.
631 *
632 * @return 0 on sucess or a negative error if an error occured.
633 */
634int rtnl_neigh_delete(struct nl_sock *sk, struct rtnl_neigh *neigh,
635		      int flags)
636{
637	struct nl_msg *msg;
638	int err;
639
640	if ((err = rtnl_neigh_build_delete_request(neigh, flags, &msg)) < 0)
641		return err;
642
643	err = nl_send_auto_complete(sk, msg);
644	nlmsg_free(msg);
645	if (err < 0)
646		return err;
647
648	return wait_for_ack(sk);
649}
650
651/** @} */
652
653/**
654 * @name Neighbour States Translations
655 * @{
656 */
657
658static struct trans_tbl neigh_states[] = {
659	__ADD(NUD_INCOMPLETE, incomplete)
660	__ADD(NUD_REACHABLE, reachable)
661	__ADD(NUD_STALE, stale)
662	__ADD(NUD_DELAY, delay)
663	__ADD(NUD_PROBE, probe)
664	__ADD(NUD_FAILED, failed)
665	__ADD(NUD_NOARP, norarp)
666	__ADD(NUD_PERMANENT, permanent)
667};
668
669char * rtnl_neigh_state2str(int state, char *buf, size_t len)
670{
671	return __flags2str(state, buf, len, neigh_states,
672	    ARRAY_SIZE(neigh_states));
673}
674
675int rtnl_neigh_str2state(const char *name)
676{
677	return __str2type(name, neigh_states, ARRAY_SIZE(neigh_states));
678}
679
680/** @} */
681
682/**
683 * @name Neighbour Flags Translations
684 * @{
685 */
686
687static struct trans_tbl neigh_flags[] = {
688	__ADD(NTF_PROXY, proxy)
689	__ADD(NTF_ROUTER, router)
690};
691
692char * rtnl_neigh_flags2str(int flags, char *buf, size_t len)
693{
694	return __flags2str(flags, buf, len, neigh_flags,
695	    ARRAY_SIZE(neigh_flags));
696}
697
698int rtnl_neigh_str2flag(const char *name)
699{
700	return __str2type(name, neigh_flags, ARRAY_SIZE(neigh_flags));
701}
702
703/** @} */
704
705/**
706 * @name Attributes
707 * @{
708 */
709
710void rtnl_neigh_set_state(struct rtnl_neigh *neigh, int state)
711{
712	neigh->n_state_mask |= state;
713	neigh->n_state |= state;
714	neigh->ce_mask |= NEIGH_ATTR_STATE;
715}
716
717int rtnl_neigh_get_state(struct rtnl_neigh *neigh)
718{
719	if (neigh->ce_mask & NEIGH_ATTR_STATE)
720		return neigh->n_state;
721	else
722		return -1;
723}
724
725void rtnl_neigh_unset_state(struct rtnl_neigh *neigh, int state)
726{
727	neigh->n_state_mask |= state;
728	neigh->n_state &= ~state;
729	neigh->ce_mask |= NEIGH_ATTR_STATE;
730}
731
732void rtnl_neigh_set_flags(struct rtnl_neigh *neigh, unsigned int flags)
733{
734	neigh->n_flag_mask |= flags;
735	neigh->n_flags |= flags;
736	neigh->ce_mask |= NEIGH_ATTR_FLAGS;
737}
738
739unsigned int rtnl_neigh_get_flags(struct rtnl_neigh *neigh)
740{
741	return neigh->n_flags;
742}
743
744void rtnl_neigh_unset_flags(struct rtnl_neigh *neigh, unsigned int flags)
745{
746	neigh->n_flag_mask |= flags;
747	neigh->n_flags &= ~flags;
748	neigh->ce_mask |= NEIGH_ATTR_FLAGS;
749}
750
751void rtnl_neigh_set_ifindex(struct rtnl_neigh *neigh, int ifindex)
752{
753	neigh->n_ifindex = ifindex;
754	neigh->ce_mask |= NEIGH_ATTR_IFINDEX;
755}
756
757int rtnl_neigh_get_ifindex(struct rtnl_neigh *neigh)
758{
759	return neigh->n_ifindex;
760}
761
762static inline int __assign_addr(struct rtnl_neigh *neigh, struct nl_addr **pos,
763			        struct nl_addr *new, int flag, int nocheck)
764{
765	if (!nocheck) {
766		if (neigh->ce_mask & NEIGH_ATTR_FAMILY) {
767			if (new->a_family != neigh->n_family)
768				return -NLE_AF_MISMATCH;
769		} else {
770			neigh->n_family = new->a_family;
771			neigh->ce_mask |= NEIGH_ATTR_FAMILY;
772		}
773	}
774
775	if (*pos)
776		nl_addr_put(*pos);
777
778	nl_addr_get(new);
779	*pos = new;
780
781	neigh->ce_mask |= flag;
782
783	return 0;
784}
785
786void rtnl_neigh_set_lladdr(struct rtnl_neigh *neigh, struct nl_addr *addr)
787{
788	__assign_addr(neigh, &neigh->n_lladdr, addr, NEIGH_ATTR_LLADDR, 1);
789}
790
791struct nl_addr *rtnl_neigh_get_lladdr(struct rtnl_neigh *neigh)
792{
793	if (neigh->ce_mask & NEIGH_ATTR_LLADDR)
794		return neigh->n_lladdr;
795	else
796		return NULL;
797}
798
799int rtnl_neigh_set_dst(struct rtnl_neigh *neigh, struct nl_addr *addr)
800{
801	return __assign_addr(neigh, &neigh->n_dst, addr,
802			     NEIGH_ATTR_DST, 0);
803}
804
805struct nl_addr *rtnl_neigh_get_dst(struct rtnl_neigh *neigh)
806{
807	if (neigh->ce_mask & NEIGH_ATTR_DST)
808		return neigh->n_dst;
809	else
810		return NULL;
811}
812
813void rtnl_neigh_set_family(struct rtnl_neigh *neigh, int family)
814{
815	neigh->n_family = family;
816	neigh->ce_mask |= NEIGH_ATTR_FAMILY;
817}
818
819int rtnl_neigh_get_family(struct rtnl_neigh *neigh)
820{
821	return neigh->n_family;
822}
823
824void rtnl_neigh_set_type(struct rtnl_neigh *neigh, int type)
825{
826	neigh->n_type = type;
827	neigh->ce_mask = NEIGH_ATTR_TYPE;
828}
829
830int rtnl_neigh_get_type(struct rtnl_neigh *neigh)
831{
832	if (neigh->ce_mask & NEIGH_ATTR_TYPE)
833		return neigh->n_type;
834	else
835		return -1;
836}
837
838/** @} */
839
840static struct nl_object_ops neigh_obj_ops = {
841	.oo_name		= "route/neigh",
842	.oo_size		= sizeof(struct rtnl_neigh),
843	.oo_free_data		= neigh_free_data,
844	.oo_clone		= neigh_clone,
845	.oo_dump = {
846	    [NL_DUMP_LINE]	= neigh_dump_line,
847	    [NL_DUMP_DETAILS]	= neigh_dump_details,
848	    [NL_DUMP_STATS]	= neigh_dump_stats,
849	    [NL_DUMP_ENV]	= neigh_dump_env,
850	},
851	.oo_compare		= neigh_compare,
852	.oo_attrs2str		= neigh_attrs2str,
853	.oo_id_attrs		= (NEIGH_ATTR_IFINDEX | NEIGH_ATTR_DST | NEIGH_ATTR_FAMILY),
854};
855
856static struct nl_af_group neigh_groups[] = {
857	{ AF_UNSPEC, RTNLGRP_NEIGH },
858	{ END_OF_GROUP_LIST },
859};
860
861static struct nl_cache_ops rtnl_neigh_ops = {
862	.co_name		= "route/neigh",
863	.co_hdrsize		= sizeof(struct ndmsg),
864	.co_msgtypes		= {
865					{ RTM_NEWNEIGH, NL_ACT_NEW, "new" },
866					{ RTM_DELNEIGH, NL_ACT_DEL, "del" },
867					{ RTM_GETNEIGH, NL_ACT_GET, "get" },
868					END_OF_MSGTYPES_LIST,
869				  },
870	.co_protocol		= NETLINK_ROUTE,
871	.co_groups		= neigh_groups,
872	.co_request_update	= neigh_request_update,
873	.co_msg_parser		= neigh_msg_parser,
874	.co_obj_ops		= &neigh_obj_ops,
875};
876
877static void __init neigh_init(void)
878{
879	nl_cache_mngt_register(&rtnl_neigh_ops);
880}
881
882static void __exit neigh_exit(void)
883{
884	nl_cache_mngt_unregister(&rtnl_neigh_ops);
885}
886
887/** @} */
888