]>
Commit | Line | Data |
---|---|---|
ad1ad5c8 | 1 | /*** |
34437b4f | 2 | This file is part of systemd. |
ad1ad5c8 | 3 | |
34437b4f LP |
4 | Copyright (C) 2014 Tom Gundersen |
5 | Copyright (C) 2014 Susant Sahani | |
ad1ad5c8 | 6 | |
34437b4f LP |
7 | systemd is free software; you can redistribute it and/or modify it |
8 | under the terms of the GNU Lesser General Public License as published by | |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
10 | (at your option) any later version. | |
ad1ad5c8 | 11 | |
34437b4f LP |
12 | systemd is distributed in the hope that it will be useful, but |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | Lesser General Public License for more details. | |
ad1ad5c8 | 16 | |
34437b4f LP |
17 | You should have received a copy of the GNU Lesser General Public License |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
ad1ad5c8 SS |
19 | ***/ |
20 | ||
21 | #include <arpa/inet.h> | |
22 | ||
ad1ad5c8 | 23 | #include "sd-lldp.h" |
07630cea | 24 | |
b5efdb8a | 25 | #include "alloc-util.h" |
3ffd4af2 | 26 | #include "fd-util.h" |
ad1ad5c8 | 27 | #include "lldp-internal.h" |
34437b4f | 28 | #include "lldp-neighbor.h" |
032b27f5 | 29 | #include "lldp-network.h" |
34437b4f | 30 | #include "socket-util.h" |
b553a6b1 | 31 | #include "ether-addr-util.h" |
49699bac | 32 | |
34437b4f | 33 | #define LLDP_DEFAULT_NEIGHBORS_MAX 128U |
032b27f5 | 34 | |
34437b4f LP |
35 | static void lldp_flush_neighbors(sd_lldp *lldp) { |
36 | sd_lldp_neighbor *n; | |
ad1ad5c8 SS |
37 | |
38 | assert(lldp); | |
ad1ad5c8 | 39 | |
34437b4f LP |
40 | while ((n = hashmap_first(lldp->neighbor_by_id))) |
41 | lldp_neighbor_unlink(n); | |
ad1ad5c8 SS |
42 | } |
43 | ||
90dffb22 LP |
44 | static void lldp_callback(sd_lldp *lldp, sd_lldp_event event, sd_lldp_neighbor *n) { |
45 | assert(lldp); | |
46 | assert(n); | |
47 | ||
48 | log_lldp("Invoking callback for '%c'.", event); | |
49 | ||
50 | if (!lldp->callback) | |
51 | return; | |
52 | ||
53 | lldp->callback(lldp, event, n, lldp->userdata); | |
54 | } | |
55 | ||
34437b4f | 56 | static int lldp_make_space(sd_lldp *lldp, size_t extra) { |
34437b4f LP |
57 | usec_t t = USEC_INFINITY; |
58 | bool changed = false; | |
ad1ad5c8 | 59 | |
34437b4f | 60 | assert(lldp); |
ad1ad5c8 | 61 | |
34437b4f LP |
62 | /* Remove all entries that are past their TTL, and more until at least the specified number of extra entries |
63 | * are free. */ | |
ad1ad5c8 | 64 | |
34437b4f | 65 | for (;;) { |
90dffb22 LP |
66 | _cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL; |
67 | ||
34437b4f LP |
68 | n = prioq_peek(lldp->neighbor_by_expiry); |
69 | if (!n) | |
859c37b1 | 70 | break; |
859c37b1 | 71 | |
90dffb22 LP |
72 | sd_lldp_neighbor_ref(n); |
73 | ||
34437b4f LP |
74 | if (hashmap_size(lldp->neighbor_by_id) > LESS_BY(lldp->neighbors_max, extra)) |
75 | goto remove_one; | |
859c37b1 | 76 | |
34437b4f LP |
77 | if (t == USEC_INFINITY) |
78 | t = now(clock_boottime_or_monotonic()); | |
859c37b1 | 79 | |
34437b4f | 80 | if (n->until > t) |
859c37b1 | 81 | break; |
859c37b1 | 82 | |
34437b4f LP |
83 | remove_one: |
84 | lldp_neighbor_unlink(n); | |
90dffb22 | 85 | lldp_callback(lldp, SD_LLDP_EVENT_REMOVED, n); |
34437b4f LP |
86 | changed = true; |
87 | } | |
859c37b1 | 88 | |
34437b4f LP |
89 | return changed; |
90 | } | |
ad1ad5c8 | 91 | |
90dffb22 LP |
92 | static bool lldp_keep_neighbor(sd_lldp *lldp, sd_lldp_neighbor *n) { |
93 | assert(lldp); | |
94 | assert(n); | |
95 | ||
96 | /* Don't keep data with a zero TTL */ | |
97 | if (n->ttl <= 0) | |
98 | return false; | |
99 | ||
100 | /* Filter out data from the filter address */ | |
101 | if (!ether_addr_is_null(&lldp->filter_address) && | |
102 | ether_addr_equal(&lldp->filter_address, &n->source_address)) | |
103 | return false; | |
104 | ||
105 | /* Only add if the neighbor has a capability we are interested in. Note that we also store all neighbors with | |
106 | * no caps field set. */ | |
107 | if (n->has_capabilities && | |
108 | (n->enabled_capabilities & lldp->capability_mask) == 0) | |
109 | return false; | |
110 | ||
111 | /* Keep everything else */ | |
112 | return true; | |
113 | } | |
114 | ||
34437b4f | 115 | static int lldp_add_neighbor(sd_lldp *lldp, sd_lldp_neighbor *n) { |
90dffb22 LP |
116 | _cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *old = NULL; |
117 | bool keep; | |
34437b4f | 118 | int r; |
ad1ad5c8 | 119 | |
34437b4f LP |
120 | assert(lldp); |
121 | assert(n); | |
122 | assert(!n->lldp); | |
123 | ||
90dffb22 LP |
124 | keep = lldp_keep_neighbor(lldp, n); |
125 | ||
34437b4f LP |
126 | /* First retrieve the old entry for this MSAP */ |
127 | old = hashmap_get(lldp->neighbor_by_id, &n->id); | |
128 | if (old) { | |
90dffb22 LP |
129 | sd_lldp_neighbor_ref(old); |
130 | ||
131 | if (!keep) { | |
132 | lldp_neighbor_unlink(old); | |
133 | lldp_callback(lldp, SD_LLDP_EVENT_REMOVED, old); | |
134 | return 0; | |
135 | } | |
136 | ||
34437b4f LP |
137 | if (lldp_neighbor_equal(n, old)) { |
138 | /* Is this equal, then restart the TTL counter, but don't do anyting else. */ | |
139 | lldp_neighbor_start_ttl(old); | |
90dffb22 | 140 | lldp_callback(lldp, SD_LLDP_EVENT_REFRESHED, old); |
34437b4f | 141 | return 0; |
ad1ad5c8 | 142 | } |
34437b4f LP |
143 | |
144 | /* Data changed, remove the old entry, and add a new one */ | |
145 | lldp_neighbor_unlink(old); | |
ad1ad5c8 | 146 | |
90dffb22 LP |
147 | } else if (!keep) |
148 | return 0; | |
ad1ad5c8 | 149 | |
34437b4f LP |
150 | /* Then, make room for at least one new neighbor */ |
151 | lldp_make_space(lldp, 1); | |
ad1ad5c8 | 152 | |
34437b4f LP |
153 | r = hashmap_put(lldp->neighbor_by_id, &n->id, n); |
154 | if (r < 0) | |
90dffb22 | 155 | goto finish; |
ad1ad5c8 | 156 | |
34437b4f LP |
157 | r = prioq_put(lldp->neighbor_by_expiry, n, &n->prioq_idx); |
158 | if (r < 0) { | |
159 | assert_se(hashmap_remove(lldp->neighbor_by_id, &n->id) == n); | |
90dffb22 | 160 | goto finish; |
ad1ad5c8 SS |
161 | } |
162 | ||
34437b4f | 163 | n->lldp = lldp; |
ad1ad5c8 | 164 | |
90dffb22 LP |
165 | lldp_neighbor_start_ttl(n); |
166 | lldp_callback(lldp, old ? SD_LLDP_EVENT_UPDATED : SD_LLDP_EVENT_ADDED, n); | |
167 | ||
168 | return 1; | |
169 | ||
170 | finish: | |
171 | if (old) | |
172 | lldp_callback(lldp, SD_LLDP_EVENT_REMOVED, n); | |
173 | ||
174 | return r; | |
ad1ad5c8 SS |
175 | } |
176 | ||
34437b4f LP |
177 | static int lldp_handle_datagram(sd_lldp *lldp, sd_lldp_neighbor *n) { |
178 | int r; | |
ad1ad5c8 | 179 | |
34437b4f LP |
180 | assert(lldp); |
181 | assert(n); | |
ad1ad5c8 | 182 | |
34437b4f LP |
183 | r = lldp_neighbor_parse(n); |
184 | if (r == -EBADMSG) /* Ignore bad messages */ | |
185 | return 0; | |
186 | if (r < 0) | |
187 | return r; | |
ad1ad5c8 | 188 | |
34437b4f LP |
189 | r = lldp_add_neighbor(lldp, n); |
190 | if (r < 0) { | |
191 | log_lldp_errno(r, "Failed to add datagram. Ignoring."); | |
192 | return 0; | |
ad1ad5c8 | 193 | } |
ad1ad5c8 | 194 | |
34437b4f | 195 | log_lldp("Successfully processed LLDP datagram."); |
34437b4f | 196 | return 0; |
ad1ad5c8 SS |
197 | } |
198 | ||
34437b4f LP |
199 | static int lldp_receive_datagram(sd_event_source *s, int fd, uint32_t revents, void *userdata) { |
200 | _cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL; | |
201 | ssize_t space, length; | |
202 | sd_lldp *lldp = userdata; | |
49699bac | 203 | |
34437b4f | 204 | assert(fd >= 0); |
49699bac | 205 | assert(lldp); |
49699bac | 206 | |
34437b4f LP |
207 | space = next_datagram_size_fd(fd); |
208 | if (space < 0) | |
209 | return log_lldp_errno(space, "Failed to determine datagram size to read: %m"); | |
49699bac | 210 | |
34437b4f LP |
211 | n = lldp_neighbor_new(space); |
212 | if (!n) | |
213 | return -ENOMEM; | |
49699bac | 214 | |
34437b4f LP |
215 | length = recv(fd, LLDP_NEIGHBOR_RAW(n), n->raw_size, MSG_DONTWAIT); |
216 | if (length < 0) | |
217 | return log_lldp_errno(errno, "Failed to read LLDP datagram: %m"); | |
dacd6cee | 218 | |
34437b4f LP |
219 | if ((size_t) length != n->raw_size) { |
220 | log_lldp("Packet size mismatch."); | |
221 | return -EINVAL; | |
222 | } | |
49699bac | 223 | |
34437b4f | 224 | return lldp_handle_datagram(lldp, n); |
49699bac SS |
225 | } |
226 | ||
34437b4f | 227 | _public_ int sd_lldp_start(sd_lldp *lldp) { |
ad1ad5c8 SS |
228 | int r; |
229 | ||
230 | assert_return(lldp, -EINVAL); | |
ad1ad5c8 | 231 | |
032b27f5 LP |
232 | if (lldp->fd >= 0) |
233 | return 0; | |
ad1ad5c8 | 234 | |
34437b4f | 235 | assert(!lldp->io_event_source); |
49699bac | 236 | |
032b27f5 LP |
237 | lldp->fd = lldp_network_bind_raw_socket(lldp->ifindex); |
238 | if (lldp->fd < 0) | |
239 | return lldp->fd; | |
240 | ||
241 | if (lldp->event) { | |
34437b4f | 242 | r = sd_event_add_io(lldp->event, &lldp->io_event_source, lldp->fd, EPOLLIN, lldp_receive_datagram, lldp); |
032b27f5 LP |
243 | if (r < 0) |
244 | goto fail; | |
245 | ||
34437b4f | 246 | r = sd_event_source_set_priority(lldp->io_event_source, lldp->event_priority); |
032b27f5 LP |
247 | if (r < 0) |
248 | goto fail; | |
249 | ||
34437b4f | 250 | (void) sd_event_source_set_description(lldp->io_event_source, "lldp-io"); |
ad1ad5c8 SS |
251 | } |
252 | ||
032b27f5 LP |
253 | return 1; |
254 | ||
255 | fail: | |
34437b4f | 256 | lldp->io_event_source = sd_event_source_unref(lldp->io_event_source); |
032b27f5 LP |
257 | lldp->fd = safe_close(lldp->fd); |
258 | ||
259 | return r; | |
ad1ad5c8 SS |
260 | } |
261 | ||
34437b4f | 262 | _public_ int sd_lldp_stop(sd_lldp *lldp) { |
ad1ad5c8 | 263 | assert_return(lldp, -EINVAL); |
ad1ad5c8 | 264 | |
032b27f5 LP |
265 | if (lldp->fd < 0) |
266 | return 0; | |
ad1ad5c8 | 267 | |
34437b4f LP |
268 | lldp->timer_event_source = sd_event_source_unref(lldp->timer_event_source); |
269 | lldp->io_event_source = sd_event_source_unref(lldp->io_event_source); | |
032b27f5 | 270 | lldp->fd = safe_close(lldp->fd); |
ad1ad5c8 | 271 | |
34437b4f | 272 | lldp_flush_neighbors(lldp); |
ad1ad5c8 | 273 | |
032b27f5 | 274 | return 1; |
ad1ad5c8 SS |
275 | } |
276 | ||
34437b4f | 277 | _public_ int sd_lldp_attach_event(sd_lldp *lldp, sd_event *event, int64_t priority) { |
ad1ad5c8 SS |
278 | int r; |
279 | ||
280 | assert_return(lldp, -EINVAL); | |
032b27f5 LP |
281 | assert_return(lldp->fd < 0, -EBUSY); |
282 | assert_return(!lldp->event, -EBUSY); | |
ad1ad5c8 SS |
283 | |
284 | if (event) | |
032b27f5 | 285 | lldp->event = sd_event_ref(event); |
ad1ad5c8 | 286 | else { |
032b27f5 | 287 | r = sd_event_default(&lldp->event); |
ad1ad5c8 SS |
288 | if (r < 0) |
289 | return r; | |
290 | } | |
291 | ||
032b27f5 | 292 | lldp->event_priority = priority; |
ad1ad5c8 SS |
293 | |
294 | return 0; | |
295 | } | |
296 | ||
34437b4f | 297 | _public_ int sd_lldp_detach_event(sd_lldp *lldp) { |
ad1ad5c8 SS |
298 | |
299 | assert_return(lldp, -EINVAL); | |
032b27f5 | 300 | assert_return(lldp->fd < 0, -EBUSY); |
ad1ad5c8 | 301 | |
032b27f5 | 302 | lldp->event = sd_event_unref(lldp->event); |
ad1ad5c8 SS |
303 | return 0; |
304 | } | |
305 | ||
34437b4f | 306 | _public_ int sd_lldp_set_callback(sd_lldp *lldp, sd_lldp_callback_t cb, void *userdata) { |
49699bac SS |
307 | assert_return(lldp, -EINVAL); |
308 | ||
ccf86354 | 309 | lldp->callback = cb; |
49699bac SS |
310 | lldp->userdata = userdata; |
311 | ||
312 | return 0; | |
313 | } | |
314 | ||
34437b4f | 315 | _public_ sd_lldp* sd_lldp_unref(sd_lldp *lldp) { |
ad1ad5c8 SS |
316 | |
317 | if (!lldp) | |
4afd3348 | 318 | return NULL; |
ad1ad5c8 | 319 | |
34437b4f | 320 | lldp_flush_neighbors(lldp); |
ad1ad5c8 | 321 | |
34437b4f LP |
322 | hashmap_free(lldp->neighbor_by_id); |
323 | prioq_free(lldp->neighbor_by_expiry); | |
ad1ad5c8 | 324 | |
34437b4f LP |
325 | sd_event_source_unref(lldp->io_event_source); |
326 | sd_event_source_unref(lldp->timer_event_source); | |
032b27f5 LP |
327 | sd_event_unref(lldp->event); |
328 | safe_close(lldp->fd); | |
329 | ||
ad1ad5c8 | 330 | free(lldp); |
34437b4f | 331 | |
4afd3348 | 332 | return NULL; |
ad1ad5c8 SS |
333 | } |
334 | ||
34437b4f | 335 | _public_ int sd_lldp_new(sd_lldp **ret, int ifindex) { |
4afd3348 | 336 | _cleanup_(sd_lldp_unrefp) sd_lldp *lldp = NULL; |
ad1ad5c8 SS |
337 | int r; |
338 | ||
339 | assert_return(ret, -EINVAL); | |
340 | assert_return(ifindex > 0, -EINVAL); | |
ad1ad5c8 SS |
341 | |
342 | lldp = new0(sd_lldp, 1); | |
343 | if (!lldp) | |
344 | return -ENOMEM; | |
345 | ||
032b27f5 LP |
346 | lldp->fd = -1; |
347 | lldp->ifindex = ifindex; | |
34437b4f LP |
348 | lldp->neighbors_max = LLDP_DEFAULT_NEIGHBORS_MAX; |
349 | lldp->capability_mask = (uint16_t) -1; | |
ad1ad5c8 | 350 | |
34437b4f LP |
351 | lldp->neighbor_by_id = hashmap_new(&lldp_neighbor_id_hash_ops); |
352 | if (!lldp->neighbor_by_id) | |
ad1ad5c8 SS |
353 | return -ENOMEM; |
354 | ||
34437b4f | 355 | r = prioq_ensure_allocated(&lldp->neighbor_by_expiry, lldp_neighbor_prioq_compare_func); |
ad1ad5c8 SS |
356 | if (r < 0) |
357 | return r; | |
358 | ||
359 | *ret = lldp; | |
360 | lldp = NULL; | |
361 | ||
362 | return 0; | |
363 | } | |
7434883c | 364 | |
34437b4f LP |
365 | static int neighbor_compare_func(const void *a, const void *b) { |
366 | const sd_lldp_neighbor * const*x = a, * const *y = b; | |
7434883c | 367 | |
34437b4f LP |
368 | return lldp_neighbor_id_hash_ops.compare(&(*x)->id, &(*y)->id); |
369 | } | |
370 | ||
371 | static int lldp_start_timer(sd_lldp *lldp); | |
372 | ||
373 | static int on_timer_event(sd_event_source *s, uint64_t usec, void *userdata) { | |
374 | sd_lldp *lldp = userdata; | |
375 | int r, q; | |
376 | ||
377 | r = lldp_make_space(lldp, 0); | |
378 | if (r < 0) | |
379 | return log_lldp_errno(r, "Failed to make space: %m"); | |
380 | ||
381 | q = lldp_start_timer(lldp); | |
382 | if (q < 0) | |
383 | return log_lldp_errno(q, "Failed to restart timer: %m"); | |
384 | ||
34437b4f LP |
385 | return 0; |
386 | } | |
7434883c | 387 | |
34437b4f LP |
388 | static int lldp_start_timer(sd_lldp *lldp) { |
389 | sd_lldp_neighbor *n; | |
390 | int r; | |
391 | ||
392 | assert(lldp); | |
393 | ||
394 | n = prioq_peek(lldp->neighbor_by_expiry); | |
395 | if (!n) { | |
396 | ||
397 | if (lldp->timer_event_source) | |
398 | return sd_event_source_set_enabled(lldp->timer_event_source, SD_EVENT_OFF); | |
399 | ||
400 | return 0; | |
401 | } | |
402 | ||
403 | if (lldp->timer_event_source) { | |
404 | r = sd_event_source_set_time(lldp->timer_event_source, n->until); | |
405 | if (r < 0) | |
406 | return r; | |
407 | ||
408 | return sd_event_source_set_enabled(lldp->timer_event_source, SD_EVENT_ONESHOT); | |
7434883c BG |
409 | } |
410 | ||
34437b4f LP |
411 | if (!lldp->event) |
412 | return 0; | |
413 | ||
414 | r = sd_event_add_time(lldp->event, &lldp->timer_event_source, clock_boottime_or_monotonic(), n->until, 0, on_timer_event, lldp); | |
415 | if (r < 0) | |
416 | return r; | |
417 | ||
418 | r = sd_event_source_set_priority(lldp->timer_event_source, lldp->event_priority); | |
419 | if (r < 0) | |
420 | return r; | |
421 | ||
422 | (void) sd_event_source_set_description(lldp->timer_event_source, "lldp-timer"); | |
423 | return 0; | |
424 | } | |
425 | ||
426 | _public_ int sd_lldp_get_neighbors(sd_lldp *lldp, sd_lldp_neighbor ***ret) { | |
427 | sd_lldp_neighbor **l = NULL, *n; | |
428 | Iterator i; | |
429 | int k = 0, r; | |
430 | ||
431 | assert_return(lldp, -EINVAL); | |
432 | assert_return(ret, -EINVAL); | |
433 | ||
34437b4f LP |
434 | if (hashmap_isempty(lldp->neighbor_by_id)) { /* Special shortcut */ |
435 | *ret = NULL; | |
7434883c BG |
436 | return 0; |
437 | } | |
438 | ||
34437b4f LP |
439 | l = new0(sd_lldp_neighbor*, hashmap_size(lldp->neighbor_by_id)); |
440 | if (!l) | |
7434883c BG |
441 | return -ENOMEM; |
442 | ||
34437b4f LP |
443 | r = lldp_start_timer(lldp); |
444 | if (r < 0) { | |
445 | free(l); | |
446 | return r; | |
7434883c BG |
447 | } |
448 | ||
34437b4f LP |
449 | HASHMAP_FOREACH(n, lldp->neighbor_by_id, i) |
450 | l[k++] = sd_lldp_neighbor_ref(n); | |
451 | ||
452 | assert((size_t) k == hashmap_size(lldp->neighbor_by_id)); | |
453 | ||
454 | /* Return things in a stable order */ | |
455 | qsort(l, k, sizeof(sd_lldp_neighbor*), neighbor_compare_func); | |
456 | *ret = l; | |
457 | ||
458 | return k; | |
459 | } | |
460 | ||
461 | _public_ int sd_lldp_set_neighbors_max(sd_lldp *lldp, uint64_t m) { | |
462 | assert_return(lldp, -EINVAL); | |
463 | assert_return(m <= 0, -EINVAL); | |
464 | ||
465 | lldp->neighbors_max = m; | |
466 | lldp_make_space(lldp, 0); | |
467 | ||
468 | return 0; | |
469 | } | |
470 | ||
471 | _public_ int sd_lldp_match_capabilities(sd_lldp *lldp, uint16_t mask) { | |
472 | assert_return(lldp, -EINVAL); | |
473 | assert_return(mask != 0, -EINVAL); | |
474 | ||
475 | lldp->capability_mask = mask; | |
476 | ||
477 | return 0; | |
7434883c | 478 | } |
b553a6b1 LP |
479 | |
480 | _public_ int sd_lldp_set_filter_address(sd_lldp *lldp, const struct ether_addr *addr) { | |
481 | assert_return(lldp, -EINVAL); | |
482 | ||
483 | /* In order to deal nicely with bridges that send back our own packets, allow one address to be filtered, so | |
484 | * that our own can be filtered out here. */ | |
485 | ||
486 | if (!addr) { | |
487 | zero(lldp->filter_address); | |
488 | return 0; | |
489 | } | |
490 | ||
491 | lldp->filter_address = *addr; | |
492 | return 0; | |
493 | } |