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1 | /********************************************************************* | |
2 | * Copyright 2017 Cumulus Networks, Inc. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify it | |
5 | * under the terms of the GNU General Public License as published by the Free | |
6 | * Software Foundation; either version 2 of the License, or (at your option) | |
7 | * any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
12 | * more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License along | |
15 | * with this program; see the file COPYING; if not, write to the Free Software | |
16 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
17 | * | |
18 | * bfd_packet.c: implements the BFD protocol packet handling. | |
19 | * | |
20 | * Authors | |
21 | * ------- | |
22 | * Shrijeet Mukherjee [shm@cumulusnetworks.com] | |
23 | * Kanna Rajagopal [kanna@cumulusnetworks.com] | |
24 | * Radhika Mahankali [Radhika@cumulusnetworks.com] | |
25 | */ | |
26 | ||
27 | #include <zebra.h> | |
28 | ||
29 | #ifdef BFD_LINUX | |
30 | #include <linux/if_packet.h> | |
31 | #endif /* BFD_LINUX */ | |
32 | ||
33 | #include <netinet/if_ether.h> | |
34 | #include <netinet/udp.h> | |
35 | ||
36 | #include "lib/sockopt.h" | |
37 | #include "lib/checksum.h" | |
38 | #include "lib/network.h" | |
39 | ||
40 | #include "bfd.h" | |
41 | ||
42 | /* | |
43 | * Prototypes | |
44 | */ | |
45 | static int ptm_bfd_process_echo_pkt(struct bfd_vrf_global *bvrf, int s); | |
46 | int _ptm_bfd_send(struct bfd_session *bs, uint16_t *port, const void *data, | |
47 | size_t datalen); | |
48 | ||
49 | static void bfd_sd_reschedule(struct bfd_vrf_global *bvrf, int sd); | |
50 | ssize_t bfd_recv_ipv4(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl, | |
51 | ifindex_t *ifindex, struct sockaddr_any *local, | |
52 | struct sockaddr_any *peer); | |
53 | ssize_t bfd_recv_ipv6(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl, | |
54 | ifindex_t *ifindex, struct sockaddr_any *local, | |
55 | struct sockaddr_any *peer); | |
56 | int bp_udp_send(int sd, uint8_t ttl, uint8_t *data, size_t datalen, | |
57 | struct sockaddr *to, socklen_t tolen); | |
58 | int bp_bfd_echo_in(struct bfd_vrf_global *bvrf, int sd, uint8_t *ttl, | |
59 | uint32_t *my_discr, uint64_t *my_rtt); | |
60 | #ifdef BFD_LINUX | |
61 | ssize_t bfd_recv_ipv4_fp(int sd, uint8_t *msgbuf, size_t msgbuflen, | |
62 | uint8_t *ttl, ifindex_t *ifindex, | |
63 | struct sockaddr_any *local, struct sockaddr_any *peer); | |
64 | void bfd_peer_mac_set(int sd, struct bfd_session *bfd, | |
65 | struct sockaddr_any *peer, struct interface *ifp); | |
66 | int bp_udp_send_fp(int sd, uint8_t *data, size_t datalen, | |
67 | struct bfd_session *bfd); | |
68 | ssize_t bfd_recv_fp_echo(int sd, uint8_t *msgbuf, size_t msgbuflen, | |
69 | uint8_t *ttl, ifindex_t *ifindex, | |
70 | struct sockaddr_any *local, struct sockaddr_any *peer); | |
71 | #endif | |
72 | ||
73 | /* socket related prototypes */ | |
74 | static void bp_set_ipopts(int sd); | |
75 | static void bp_bind_ip(int sd, uint16_t port); | |
76 | static void bp_set_ipv6opts(int sd); | |
77 | static void bp_bind_ipv6(int sd, uint16_t port); | |
78 | ||
79 | ||
80 | /* | |
81 | * Functions | |
82 | */ | |
83 | int _ptm_bfd_send(struct bfd_session *bs, uint16_t *port, const void *data, | |
84 | size_t datalen) | |
85 | { | |
86 | struct sockaddr *sa; | |
87 | struct sockaddr_in sin; | |
88 | struct sockaddr_in6 sin6; | |
89 | socklen_t slen; | |
90 | ssize_t rv; | |
91 | int sd = -1; | |
92 | ||
93 | if (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_IPV6)) { | |
94 | memset(&sin6, 0, sizeof(sin6)); | |
95 | sin6.sin6_family = AF_INET6; | |
96 | memcpy(&sin6.sin6_addr, &bs->key.peer, sizeof(sin6.sin6_addr)); | |
97 | if (bs->ifp && IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr)) | |
98 | sin6.sin6_scope_id = bs->ifp->ifindex; | |
99 | ||
100 | sin6.sin6_port = | |
101 | (port) ? *port | |
102 | : (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH)) | |
103 | ? htons(BFD_DEF_MHOP_DEST_PORT) | |
104 | : htons(BFD_DEFDESTPORT); | |
105 | ||
106 | sd = bs->sock; | |
107 | sa = (struct sockaddr *)&sin6; | |
108 | slen = sizeof(sin6); | |
109 | } else { | |
110 | memset(&sin, 0, sizeof(sin)); | |
111 | sin.sin_family = AF_INET; | |
112 | memcpy(&sin.sin_addr, &bs->key.peer, sizeof(sin.sin_addr)); | |
113 | sin.sin_port = | |
114 | (port) ? *port | |
115 | : (CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH)) | |
116 | ? htons(BFD_DEF_MHOP_DEST_PORT) | |
117 | : htons(BFD_DEFDESTPORT); | |
118 | ||
119 | sd = bs->sock; | |
120 | sa = (struct sockaddr *)&sin; | |
121 | slen = sizeof(sin); | |
122 | } | |
123 | ||
124 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
125 | sa->sa_len = slen; | |
126 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
127 | rv = sendto(sd, data, datalen, 0, sa, slen); | |
128 | if (rv <= 0) { | |
129 | if (bglobal.debug_network) | |
130 | zlog_debug("packet-send: send failure: %s", | |
131 | strerror(errno)); | |
132 | return -1; | |
133 | } | |
134 | if (rv < (ssize_t)datalen) { | |
135 | if (bglobal.debug_network) | |
136 | zlog_debug("packet-send: send partial: %s", | |
137 | strerror(errno)); | |
138 | } | |
139 | ||
140 | return 0; | |
141 | } | |
142 | ||
143 | #ifdef BFD_LINUX | |
144 | /* | |
145 | * Compute the UDP checksum. | |
146 | * | |
147 | * Checksum is not set in the packet, just computed. | |
148 | * | |
149 | * pkt | |
150 | * Packet, fully filled out except for checksum field. | |
151 | * | |
152 | * pktsize | |
153 | * sizeof(*pkt) | |
154 | * | |
155 | * ip | |
156 | * IP address that pkt will be transmitted from and too. | |
157 | * | |
158 | * Returns: | |
159 | * Checksum in network byte order. | |
160 | */ | |
161 | static uint16_t bfd_pkt_checksum(struct udphdr *pkt, size_t pktsize, | |
162 | struct in6_addr *ip, sa_family_t family) | |
163 | { | |
164 | uint16_t chksum; | |
165 | ||
166 | pkt->check = 0; | |
167 | ||
168 | if (family == AF_INET6) { | |
169 | struct ipv6_ph ph = {}; | |
170 | ||
171 | memcpy(&ph.src, ip, sizeof(ph.src)); | |
172 | memcpy(&ph.dst, ip, sizeof(ph.dst)); | |
173 | ph.ulpl = htons(pktsize); | |
174 | ph.next_hdr = IPPROTO_UDP; | |
175 | chksum = in_cksum_with_ph6(&ph, pkt, pktsize); | |
176 | } else { | |
177 | struct ipv4_ph ph = {}; | |
178 | ||
179 | memcpy(&ph.src, ip, sizeof(ph.src)); | |
180 | memcpy(&ph.dst, ip, sizeof(ph.dst)); | |
181 | ph.proto = IPPROTO_UDP; | |
182 | ph.len = htons(pktsize); | |
183 | chksum = in_cksum_with_ph4(&ph, pkt, pktsize); | |
184 | } | |
185 | ||
186 | return chksum; | |
187 | } | |
188 | ||
189 | /* | |
190 | * This routine creates the entire ECHO packet so that it will be looped | |
191 | * in the forwarding plane of the peer router instead of going up the | |
192 | * stack in BFD to be looped. If we haven't learned the peers MAC yet | |
193 | * no echo is sent. | |
194 | * | |
195 | * echo packet with src/dst IP equal to local IP | |
196 | * dest MAC as peer's MAC | |
197 | * | |
198 | * currently support ipv4 | |
199 | */ | |
200 | void ptm_bfd_echo_fp_snd(struct bfd_session *bfd) | |
201 | { | |
202 | int sd; | |
203 | struct bfd_vrf_global *bvrf = bfd_vrf_look_by_session(bfd); | |
204 | int total_len = 0; | |
205 | struct ethhdr *eth; | |
206 | struct udphdr *uh; | |
207 | struct iphdr *iph; | |
208 | struct bfd_echo_pkt *beph; | |
209 | static char sendbuff[100]; | |
210 | struct timeval time_sent; | |
211 | ||
212 | if (!bvrf) | |
213 | return; | |
214 | if (!CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET)) | |
215 | return; | |
216 | if (!CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE)) | |
217 | SET_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE); | |
218 | ||
219 | memset(sendbuff, 0, sizeof(sendbuff)); | |
220 | ||
221 | /* add eth hdr */ | |
222 | eth = (struct ethhdr *)(sendbuff); | |
223 | memcpy(eth->h_source, bfd->ifp->hw_addr, sizeof(eth->h_source)); | |
224 | memcpy(eth->h_dest, bfd->peer_hw_addr, sizeof(eth->h_dest)); | |
225 | ||
226 | total_len += sizeof(struct ethhdr); | |
227 | ||
228 | sd = bvrf->bg_echo; | |
229 | eth->h_proto = htons(ETH_P_IP); | |
230 | ||
231 | /* add ip hdr */ | |
232 | iph = (struct iphdr *)(sendbuff + sizeof(struct ethhdr)); | |
233 | ||
234 | iph->ihl = sizeof(struct ip) >> 2; | |
235 | iph->version = IPVERSION; | |
236 | iph->tos = IPTOS_PREC_INTERNETCONTROL; | |
237 | iph->id = (uint16_t)frr_weak_random(); | |
238 | iph->ttl = BFD_TTL_VAL; | |
239 | iph->protocol = IPPROTO_UDP; | |
240 | memcpy(&iph->saddr, &bfd->local_address.sa_sin.sin_addr, | |
241 | sizeof(bfd->local_address.sa_sin.sin_addr)); | |
242 | memcpy(&iph->daddr, &bfd->local_address.sa_sin.sin_addr, | |
243 | sizeof(bfd->local_address.sa_sin.sin_addr)); | |
244 | total_len += sizeof(struct iphdr); | |
245 | ||
246 | /* add udp hdr */ | |
247 | uh = (struct udphdr *)(sendbuff + sizeof(struct iphdr) + | |
248 | sizeof(struct ethhdr)); | |
249 | uh->source = htons(BFD_DEF_ECHO_PORT); | |
250 | uh->dest = htons(BFD_DEF_ECHO_PORT); | |
251 | ||
252 | total_len += sizeof(struct udphdr); | |
253 | ||
254 | /* add bfd echo */ | |
255 | beph = (struct bfd_echo_pkt *)(sendbuff + sizeof(struct udphdr) + | |
256 | sizeof(struct iphdr) + | |
257 | sizeof(struct ethhdr)); | |
258 | ||
259 | beph->ver = BFD_ECHO_VERSION; | |
260 | beph->len = BFD_ECHO_PKT_LEN; | |
261 | beph->my_discr = htonl(bfd->discrs.my_discr); | |
262 | ||
263 | /* RTT calculation: add starting time in packet */ | |
264 | monotime(&time_sent); | |
265 | beph->time_sent_sec = htobe64(time_sent.tv_sec); | |
266 | beph->time_sent_usec = htobe64(time_sent.tv_usec); | |
267 | ||
268 | total_len += sizeof(struct bfd_echo_pkt); | |
269 | uh->len = | |
270 | htons(total_len - sizeof(struct iphdr) - sizeof(struct ethhdr)); | |
271 | uh->check = bfd_pkt_checksum( | |
272 | uh, (total_len - sizeof(struct iphdr) - sizeof(struct ethhdr)), | |
273 | (struct in6_addr *)&iph->saddr, AF_INET); | |
274 | ||
275 | iph->tot_len = htons(total_len - sizeof(struct ethhdr)); | |
276 | iph->check = in_cksum((const void *)iph, sizeof(struct iphdr)); | |
277 | ||
278 | if (bp_udp_send_fp(sd, (uint8_t *)&sendbuff, total_len, bfd) == -1) | |
279 | return; | |
280 | ||
281 | bfd->stats.tx_echo_pkt++; | |
282 | } | |
283 | #endif | |
284 | ||
285 | void ptm_bfd_echo_snd(struct bfd_session *bfd) | |
286 | { | |
287 | struct sockaddr *sa; | |
288 | socklen_t salen; | |
289 | int sd; | |
290 | struct bfd_echo_pkt bep; | |
291 | struct sockaddr_in sin; | |
292 | struct sockaddr_in6 sin6; | |
293 | struct bfd_vrf_global *bvrf = bfd_vrf_look_by_session(bfd); | |
294 | ||
295 | if (!bvrf) | |
296 | return; | |
297 | if (!CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE)) | |
298 | SET_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE); | |
299 | ||
300 | memset(&bep, 0, sizeof(bep)); | |
301 | bep.ver = BFD_ECHO_VERSION; | |
302 | bep.len = BFD_ECHO_PKT_LEN; | |
303 | bep.my_discr = htonl(bfd->discrs.my_discr); | |
304 | ||
305 | if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_IPV6)) { | |
306 | if (bvrf->bg_echov6 == -1) | |
307 | return; | |
308 | sd = bvrf->bg_echov6; | |
309 | memset(&sin6, 0, sizeof(sin6)); | |
310 | sin6.sin6_family = AF_INET6; | |
311 | memcpy(&sin6.sin6_addr, &bfd->key.peer, sizeof(sin6.sin6_addr)); | |
312 | if (bfd->ifp && IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr)) | |
313 | sin6.sin6_scope_id = bfd->ifp->ifindex; | |
314 | ||
315 | sin6.sin6_port = htons(BFD_DEF_ECHO_PORT); | |
316 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
317 | sin6.sin6_len = sizeof(sin6); | |
318 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
319 | ||
320 | sa = (struct sockaddr *)&sin6; | |
321 | salen = sizeof(sin6); | |
322 | } else { | |
323 | sd = bvrf->bg_echo; | |
324 | memset(&sin, 0, sizeof(sin)); | |
325 | sin.sin_family = AF_INET; | |
326 | memcpy(&sin.sin_addr, &bfd->key.peer, sizeof(sin.sin_addr)); | |
327 | sin.sin_port = htons(BFD_DEF_ECHO_PORT); | |
328 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
329 | sin.sin_len = sizeof(sin); | |
330 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
331 | ||
332 | sa = (struct sockaddr *)&sin; | |
333 | salen = sizeof(sin); | |
334 | } | |
335 | if (bp_udp_send(sd, BFD_TTL_VAL, (uint8_t *)&bep, sizeof(bep), sa, | |
336 | salen) | |
337 | == -1) | |
338 | return; | |
339 | ||
340 | bfd->stats.tx_echo_pkt++; | |
341 | } | |
342 | ||
343 | static int ptm_bfd_process_echo_pkt(struct bfd_vrf_global *bvrf, int s) | |
344 | { | |
345 | struct bfd_session *bfd; | |
346 | uint32_t my_discr = 0; | |
347 | uint64_t my_rtt = 0; | |
348 | uint8_t ttl = 0; | |
349 | ||
350 | /* Receive and parse echo packet. */ | |
351 | if (bp_bfd_echo_in(bvrf, s, &ttl, &my_discr, &my_rtt) == -1) | |
352 | return 0; | |
353 | ||
354 | /* Your discriminator not zero - use it to find session */ | |
355 | bfd = bfd_id_lookup(my_discr); | |
356 | if (bfd == NULL) { | |
357 | if (bglobal.debug_network) | |
358 | zlog_debug("echo-packet: no matching session (id:%u)", | |
359 | my_discr); | |
360 | return -1; | |
361 | } | |
362 | ||
363 | if (!CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_ECHO_ACTIVE)) { | |
364 | if (bglobal.debug_network) | |
365 | zlog_debug("echo-packet: echo disabled [%s] (id:%u)", | |
366 | bs_to_string(bfd), my_discr); | |
367 | return -1; | |
368 | } | |
369 | ||
370 | /* RTT Calculation: add current RTT to samples */ | |
371 | if (my_rtt != 0) { | |
372 | bfd->rtt[bfd->rtt_index] = my_rtt; | |
373 | bfd->rtt_index++; | |
374 | if (bfd->rtt_index >= BFD_RTT_SAMPLE) | |
375 | bfd->rtt_index = 0; | |
376 | if (bfd->rtt_valid < BFD_RTT_SAMPLE) | |
377 | bfd->rtt_valid++; | |
378 | } | |
379 | ||
380 | bfd->stats.rx_echo_pkt++; | |
381 | ||
382 | /* Compute detect time */ | |
383 | bfd->echo_detect_TO = bfd->remote_detect_mult * bfd->echo_xmt_TO; | |
384 | ||
385 | /* Update echo receive timeout. */ | |
386 | if (bfd->echo_detect_TO > 0) | |
387 | bfd_echo_recvtimer_update(bfd); | |
388 | ||
389 | return 0; | |
390 | } | |
391 | ||
392 | void ptm_bfd_snd(struct bfd_session *bfd, int fbit) | |
393 | { | |
394 | struct bfd_pkt cp = {}; | |
395 | ||
396 | /* Set fields according to section 6.5.7 */ | |
397 | cp.diag = bfd->local_diag; | |
398 | BFD_SETVER(cp.diag, BFD_VERSION); | |
399 | cp.flags = 0; | |
400 | BFD_SETSTATE(cp.flags, bfd->ses_state); | |
401 | ||
402 | if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_CBIT)) | |
403 | BFD_SETCBIT(cp.flags, BFD_CBIT); | |
404 | ||
405 | BFD_SETDEMANDBIT(cp.flags, BFD_DEF_DEMAND); | |
406 | ||
407 | /* | |
408 | * Polling and Final can't be set at the same time. | |
409 | * | |
410 | * RFC 5880, Section 6.5. | |
411 | */ | |
412 | BFD_SETFBIT(cp.flags, fbit); | |
413 | if (fbit == 0) | |
414 | BFD_SETPBIT(cp.flags, bfd->polling); | |
415 | ||
416 | cp.detect_mult = bfd->detect_mult; | |
417 | cp.len = BFD_PKT_LEN; | |
418 | cp.discrs.my_discr = htonl(bfd->discrs.my_discr); | |
419 | cp.discrs.remote_discr = htonl(bfd->discrs.remote_discr); | |
420 | if (bfd->polling) { | |
421 | cp.timers.desired_min_tx = | |
422 | htonl(bfd->timers.desired_min_tx); | |
423 | cp.timers.required_min_rx = | |
424 | htonl(bfd->timers.required_min_rx); | |
425 | } else { | |
426 | /* | |
427 | * We can only announce current setting on poll, this | |
428 | * avoids timing mismatch with our peer and give it | |
429 | * the oportunity to learn. See `bs_final_handler` for | |
430 | * more information. | |
431 | */ | |
432 | cp.timers.desired_min_tx = | |
433 | htonl(bfd->cur_timers.desired_min_tx); | |
434 | cp.timers.required_min_rx = | |
435 | htonl(bfd->cur_timers.required_min_rx); | |
436 | } | |
437 | cp.timers.required_min_echo = htonl(bfd->timers.required_min_echo_rx); | |
438 | ||
439 | if (_ptm_bfd_send(bfd, NULL, &cp, BFD_PKT_LEN) != 0) | |
440 | return; | |
441 | ||
442 | bfd->stats.tx_ctrl_pkt++; | |
443 | } | |
444 | ||
445 | #ifdef BFD_LINUX | |
446 | /* | |
447 | * receive the ipv4 echo packet that was loopback in the peers forwarding plane | |
448 | */ | |
449 | ssize_t bfd_recv_ipv4_fp(int sd, uint8_t *msgbuf, size_t msgbuflen, | |
450 | uint8_t *ttl, ifindex_t *ifindex, | |
451 | struct sockaddr_any *local, struct sockaddr_any *peer) | |
452 | { | |
453 | ssize_t mlen; | |
454 | struct sockaddr_ll msgaddr; | |
455 | struct msghdr msghdr; | |
456 | struct iovec iov[1]; | |
457 | uint16_t recv_checksum; | |
458 | uint16_t checksum; | |
459 | struct iphdr *ip; | |
460 | struct udphdr *uh; | |
461 | ||
462 | /* Prepare the recvmsg params. */ | |
463 | iov[0].iov_base = msgbuf; | |
464 | iov[0].iov_len = msgbuflen; | |
465 | ||
466 | memset(&msghdr, 0, sizeof(msghdr)); | |
467 | msghdr.msg_name = &msgaddr; | |
468 | msghdr.msg_namelen = sizeof(msgaddr); | |
469 | msghdr.msg_iov = iov; | |
470 | msghdr.msg_iovlen = 1; | |
471 | ||
472 | mlen = recvmsg(sd, &msghdr, MSG_DONTWAIT); | |
473 | if (mlen == -1) { | |
474 | if (errno != EAGAIN || errno != EWOULDBLOCK || errno != EINTR) | |
475 | zlog_err("%s: recv failed: %s", __func__, | |
476 | strerror(errno)); | |
477 | ||
478 | return -1; | |
479 | } | |
480 | ||
481 | ip = (struct iphdr *)(msgbuf + sizeof(struct ethhdr)); | |
482 | ||
483 | /* verify ip checksum */ | |
484 | recv_checksum = ip->check; | |
485 | ip->check = 0; | |
486 | checksum = in_cksum((const void *)ip, sizeof(struct iphdr)); | |
487 | if (recv_checksum != checksum) { | |
488 | if (bglobal.debug_network) | |
489 | zlog_debug( | |
490 | "%s: invalid iphdr checksum expected 0x%x rcvd 0x%x", | |
491 | __func__, checksum, recv_checksum); | |
492 | return -1; | |
493 | } | |
494 | ||
495 | *ttl = ip->ttl; | |
496 | if (*ttl != 254) { | |
497 | /* Echo should be looped in peer's forwarding plane, but it also | |
498 | * comes up to BFD so silently drop it | |
499 | */ | |
500 | if (ip->daddr == ip->saddr) | |
501 | return -1; | |
502 | ||
503 | if (bglobal.debug_network) | |
504 | zlog_debug("%s: invalid TTL: %u", __func__, *ttl); | |
505 | return -1; | |
506 | } | |
507 | ||
508 | local->sa_sin.sin_family = AF_INET; | |
509 | memcpy(&local->sa_sin.sin_addr, &ip->saddr, sizeof(ip->saddr)); | |
510 | peer->sa_sin.sin_family = AF_INET; | |
511 | memcpy(&peer->sa_sin.sin_addr, &ip->daddr, sizeof(ip->daddr)); | |
512 | ||
513 | *ifindex = msgaddr.sll_ifindex; | |
514 | ||
515 | /* verify udp checksum */ | |
516 | uh = (struct udphdr *)(msgbuf + sizeof(struct iphdr) + | |
517 | sizeof(struct ethhdr)); | |
518 | recv_checksum = uh->check; | |
519 | uh->check = 0; | |
520 | checksum = bfd_pkt_checksum(uh, ntohs(uh->len), | |
521 | (struct in6_addr *)&ip->saddr, AF_INET); | |
522 | if (recv_checksum != checksum) { | |
523 | if (bglobal.debug_network) | |
524 | zlog_debug( | |
525 | "%s: invalid udphdr checksum expected 0x%x rcvd 0x%x", | |
526 | __func__, checksum, recv_checksum); | |
527 | return -1; | |
528 | } | |
529 | return mlen; | |
530 | } | |
531 | #endif | |
532 | ||
533 | ssize_t bfd_recv_ipv4(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl, | |
534 | ifindex_t *ifindex, struct sockaddr_any *local, | |
535 | struct sockaddr_any *peer) | |
536 | { | |
537 | struct cmsghdr *cm; | |
538 | ssize_t mlen; | |
539 | struct sockaddr_in msgaddr; | |
540 | struct msghdr msghdr; | |
541 | struct iovec iov[1]; | |
542 | uint8_t cmsgbuf[255]; | |
543 | ||
544 | /* Prepare the recvmsg params. */ | |
545 | iov[0].iov_base = msgbuf; | |
546 | iov[0].iov_len = msgbuflen; | |
547 | ||
548 | memset(&msghdr, 0, sizeof(msghdr)); | |
549 | msghdr.msg_name = &msgaddr; | |
550 | msghdr.msg_namelen = sizeof(msgaddr); | |
551 | msghdr.msg_iov = iov; | |
552 | msghdr.msg_iovlen = 1; | |
553 | msghdr.msg_control = cmsgbuf; | |
554 | msghdr.msg_controllen = sizeof(cmsgbuf); | |
555 | ||
556 | mlen = recvmsg(sd, &msghdr, MSG_DONTWAIT); | |
557 | if (mlen == -1) { | |
558 | if (errno != EAGAIN) | |
559 | zlog_err("ipv4-recv: recv failed: %s", strerror(errno)); | |
560 | ||
561 | return -1; | |
562 | } | |
563 | ||
564 | /* Get source address */ | |
565 | peer->sa_sin = *((struct sockaddr_in *)(msghdr.msg_name)); | |
566 | ||
567 | /* Get and check TTL */ | |
568 | for (cm = CMSG_FIRSTHDR(&msghdr); cm != NULL; | |
569 | cm = CMSG_NXTHDR(&msghdr, cm)) { | |
570 | if (cm->cmsg_level != IPPROTO_IP) | |
571 | continue; | |
572 | ||
573 | switch (cm->cmsg_type) { | |
574 | #ifdef BFD_LINUX | |
575 | case IP_TTL: { | |
576 | uint32_t ttlval; | |
577 | ||
578 | memcpy(&ttlval, CMSG_DATA(cm), sizeof(ttlval)); | |
579 | if (ttlval > 255) { | |
580 | if (bglobal.debug_network) | |
581 | zlog_debug("%s: invalid TTL: %u", | |
582 | __func__, ttlval); | |
583 | return -1; | |
584 | } | |
585 | *ttl = ttlval; | |
586 | break; | |
587 | } | |
588 | ||
589 | case IP_PKTINFO: { | |
590 | struct in_pktinfo *pi = | |
591 | (struct in_pktinfo *)CMSG_DATA(cm); | |
592 | ||
593 | if (pi == NULL) | |
594 | break; | |
595 | ||
596 | local->sa_sin.sin_family = AF_INET; | |
597 | local->sa_sin.sin_addr = pi->ipi_addr; | |
598 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
599 | local->sa_sin.sin_len = sizeof(local->sa_sin); | |
600 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
601 | ||
602 | *ifindex = pi->ipi_ifindex; | |
603 | break; | |
604 | } | |
605 | #endif /* BFD_LINUX */ | |
606 | #ifdef BFD_BSD | |
607 | case IP_RECVTTL: { | |
608 | memcpy(ttl, CMSG_DATA(cm), sizeof(*ttl)); | |
609 | break; | |
610 | } | |
611 | ||
612 | case IP_RECVDSTADDR: { | |
613 | struct in_addr ia; | |
614 | ||
615 | memcpy(&ia, CMSG_DATA(cm), sizeof(ia)); | |
616 | local->sa_sin.sin_family = AF_INET; | |
617 | local->sa_sin.sin_addr = ia; | |
618 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
619 | local->sa_sin.sin_len = sizeof(local->sa_sin); | |
620 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
621 | break; | |
622 | } | |
623 | #endif /* BFD_BSD */ | |
624 | ||
625 | default: | |
626 | /* | |
627 | * On *BSDs we expect to land here when skipping | |
628 | * the IP_RECVIF header. It will be handled by | |
629 | * getsockopt_ifindex() below. | |
630 | */ | |
631 | /* NOTHING */ | |
632 | break; | |
633 | } | |
634 | } | |
635 | ||
636 | /* OS agnostic way of getting interface name. */ | |
637 | if (*ifindex == IFINDEX_INTERNAL) | |
638 | *ifindex = getsockopt_ifindex(AF_INET, &msghdr); | |
639 | ||
640 | return mlen; | |
641 | } | |
642 | ||
643 | ssize_t bfd_recv_ipv6(int sd, uint8_t *msgbuf, size_t msgbuflen, uint8_t *ttl, | |
644 | ifindex_t *ifindex, struct sockaddr_any *local, | |
645 | struct sockaddr_any *peer) | |
646 | { | |
647 | struct cmsghdr *cm; | |
648 | struct in6_pktinfo *pi6 = NULL; | |
649 | ssize_t mlen; | |
650 | uint32_t ttlval; | |
651 | struct sockaddr_in6 msgaddr6; | |
652 | struct msghdr msghdr6; | |
653 | struct iovec iov[1]; | |
654 | uint8_t cmsgbuf6[255]; | |
655 | ||
656 | /* Prepare the recvmsg params. */ | |
657 | iov[0].iov_base = msgbuf; | |
658 | iov[0].iov_len = msgbuflen; | |
659 | ||
660 | memset(&msghdr6, 0, sizeof(msghdr6)); | |
661 | msghdr6.msg_name = &msgaddr6; | |
662 | msghdr6.msg_namelen = sizeof(msgaddr6); | |
663 | msghdr6.msg_iov = iov; | |
664 | msghdr6.msg_iovlen = 1; | |
665 | msghdr6.msg_control = cmsgbuf6; | |
666 | msghdr6.msg_controllen = sizeof(cmsgbuf6); | |
667 | ||
668 | mlen = recvmsg(sd, &msghdr6, MSG_DONTWAIT); | |
669 | if (mlen == -1) { | |
670 | if (errno != EAGAIN) | |
671 | zlog_err("ipv6-recv: recv failed: %s", strerror(errno)); | |
672 | ||
673 | return -1; | |
674 | } | |
675 | ||
676 | /* Get source address */ | |
677 | peer->sa_sin6 = *((struct sockaddr_in6 *)(msghdr6.msg_name)); | |
678 | ||
679 | /* Get and check TTL */ | |
680 | for (cm = CMSG_FIRSTHDR(&msghdr6); cm != NULL; | |
681 | cm = CMSG_NXTHDR(&msghdr6, cm)) { | |
682 | if (cm->cmsg_level != IPPROTO_IPV6) | |
683 | continue; | |
684 | ||
685 | if (cm->cmsg_type == IPV6_HOPLIMIT) { | |
686 | memcpy(&ttlval, CMSG_DATA(cm), sizeof(ttlval)); | |
687 | if (ttlval > 255) { | |
688 | if (bglobal.debug_network) | |
689 | zlog_debug("%s: invalid TTL: %u", | |
690 | __func__, ttlval); | |
691 | return -1; | |
692 | } | |
693 | ||
694 | *ttl = ttlval; | |
695 | } else if (cm->cmsg_type == IPV6_PKTINFO) { | |
696 | pi6 = (struct in6_pktinfo *)CMSG_DATA(cm); | |
697 | if (pi6) { | |
698 | local->sa_sin6.sin6_family = AF_INET6; | |
699 | local->sa_sin6.sin6_addr = pi6->ipi6_addr; | |
700 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
701 | local->sa_sin6.sin6_len = sizeof(local->sa_sin6); | |
702 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
703 | ||
704 | *ifindex = pi6->ipi6_ifindex; | |
705 | ||
706 | /* Set scope ID for link local addresses. */ | |
707 | if (IN6_IS_ADDR_LINKLOCAL( | |
708 | &peer->sa_sin6.sin6_addr)) | |
709 | peer->sa_sin6.sin6_scope_id = *ifindex; | |
710 | if (IN6_IS_ADDR_LINKLOCAL( | |
711 | &local->sa_sin6.sin6_addr)) | |
712 | local->sa_sin6.sin6_scope_id = *ifindex; | |
713 | } | |
714 | } | |
715 | } | |
716 | ||
717 | return mlen; | |
718 | } | |
719 | ||
720 | static void bfd_sd_reschedule(struct bfd_vrf_global *bvrf, int sd) | |
721 | { | |
722 | if (sd == bvrf->bg_shop) { | |
723 | THREAD_OFF(bvrf->bg_ev[0]); | |
724 | thread_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_shop, | |
725 | &bvrf->bg_ev[0]); | |
726 | } else if (sd == bvrf->bg_mhop) { | |
727 | THREAD_OFF(bvrf->bg_ev[1]); | |
728 | thread_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_mhop, | |
729 | &bvrf->bg_ev[1]); | |
730 | } else if (sd == bvrf->bg_shop6) { | |
731 | THREAD_OFF(bvrf->bg_ev[2]); | |
732 | thread_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_shop6, | |
733 | &bvrf->bg_ev[2]); | |
734 | } else if (sd == bvrf->bg_mhop6) { | |
735 | THREAD_OFF(bvrf->bg_ev[3]); | |
736 | thread_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_mhop6, | |
737 | &bvrf->bg_ev[3]); | |
738 | } else if (sd == bvrf->bg_echo) { | |
739 | THREAD_OFF(bvrf->bg_ev[4]); | |
740 | thread_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_echo, | |
741 | &bvrf->bg_ev[4]); | |
742 | } else if (sd == bvrf->bg_echov6) { | |
743 | THREAD_OFF(bvrf->bg_ev[5]); | |
744 | thread_add_read(master, bfd_recv_cb, bvrf, bvrf->bg_echov6, | |
745 | &bvrf->bg_ev[5]); | |
746 | } | |
747 | } | |
748 | ||
749 | static void cp_debug(bool mhop, struct sockaddr_any *peer, | |
750 | struct sockaddr_any *local, ifindex_t ifindex, | |
751 | vrf_id_t vrfid, const char *fmt, ...) | |
752 | { | |
753 | char buf[512], peerstr[128], localstr[128], portstr[64], vrfstr[64]; | |
754 | va_list vl; | |
755 | ||
756 | /* Don't to any processing if debug is disabled. */ | |
757 | if (bglobal.debug_network == false) | |
758 | return; | |
759 | ||
760 | if (peer->sa_sin.sin_family) | |
761 | snprintf(peerstr, sizeof(peerstr), " peer:%s", satostr(peer)); | |
762 | else | |
763 | peerstr[0] = 0; | |
764 | ||
765 | if (local->sa_sin.sin_family) | |
766 | snprintf(localstr, sizeof(localstr), " local:%s", | |
767 | satostr(local)); | |
768 | else | |
769 | localstr[0] = 0; | |
770 | ||
771 | if (ifindex != IFINDEX_INTERNAL) | |
772 | snprintf(portstr, sizeof(portstr), " port:%u", ifindex); | |
773 | else | |
774 | portstr[0] = 0; | |
775 | ||
776 | if (vrfid != VRF_DEFAULT) | |
777 | snprintf(vrfstr, sizeof(vrfstr), " vrf:%u", vrfid); | |
778 | else | |
779 | vrfstr[0] = 0; | |
780 | ||
781 | va_start(vl, fmt); | |
782 | vsnprintf(buf, sizeof(buf), fmt, vl); | |
783 | va_end(vl); | |
784 | ||
785 | zlog_debug("control-packet: %s [mhop:%s%s%s%s%s]", buf, | |
786 | mhop ? "yes" : "no", peerstr, localstr, portstr, vrfstr); | |
787 | } | |
788 | ||
789 | void bfd_recv_cb(struct thread *t) | |
790 | { | |
791 | int sd = THREAD_FD(t); | |
792 | struct bfd_session *bfd; | |
793 | struct bfd_pkt *cp; | |
794 | bool is_mhop; | |
795 | ssize_t mlen = 0; | |
796 | uint8_t ttl = 0; | |
797 | vrf_id_t vrfid; | |
798 | ifindex_t ifindex = IFINDEX_INTERNAL; | |
799 | struct sockaddr_any local, peer; | |
800 | uint8_t msgbuf[1516]; | |
801 | struct interface *ifp = NULL; | |
802 | struct bfd_vrf_global *bvrf = THREAD_ARG(t); | |
803 | ||
804 | /* Schedule next read. */ | |
805 | bfd_sd_reschedule(bvrf, sd); | |
806 | ||
807 | /* Handle echo packets. */ | |
808 | if (sd == bvrf->bg_echo || sd == bvrf->bg_echov6) { | |
809 | ptm_bfd_process_echo_pkt(bvrf, sd); | |
810 | return; | |
811 | } | |
812 | ||
813 | /* Sanitize input/output. */ | |
814 | memset(&local, 0, sizeof(local)); | |
815 | memset(&peer, 0, sizeof(peer)); | |
816 | ||
817 | /* Handle control packets. */ | |
818 | is_mhop = false; | |
819 | if (sd == bvrf->bg_shop || sd == bvrf->bg_mhop) { | |
820 | is_mhop = sd == bvrf->bg_mhop; | |
821 | mlen = bfd_recv_ipv4(sd, msgbuf, sizeof(msgbuf), &ttl, &ifindex, | |
822 | &local, &peer); | |
823 | } else if (sd == bvrf->bg_shop6 || sd == bvrf->bg_mhop6) { | |
824 | is_mhop = sd == bvrf->bg_mhop6; | |
825 | mlen = bfd_recv_ipv6(sd, msgbuf, sizeof(msgbuf), &ttl, &ifindex, | |
826 | &local, &peer); | |
827 | } | |
828 | ||
829 | /* | |
830 | * With netns backend, we have a separate socket in each VRF. It means | |
831 | * that bvrf here is correct and we believe the bvrf->vrf->vrf_id. | |
832 | * With VRF-lite backend, we have a single socket in the default VRF. | |
833 | * It means that we can't believe the bvrf->vrf->vrf_id. But in | |
834 | * VRF-lite, the ifindex is globally unique, so we can retrieve the | |
835 | * correct vrf_id from the interface. | |
836 | */ | |
837 | vrfid = bvrf->vrf->vrf_id; | |
838 | if (ifindex) { | |
839 | ifp = if_lookup_by_index(ifindex, vrfid); | |
840 | if (ifp) | |
841 | vrfid = ifp->vrf->vrf_id; | |
842 | } | |
843 | ||
844 | /* Implement RFC 5880 6.8.6 */ | |
845 | if (mlen < BFD_PKT_LEN) { | |
846 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
847 | "too small (%ld bytes)", mlen); | |
848 | return; | |
849 | } | |
850 | ||
851 | /* Validate single hop packet TTL. */ | |
852 | if ((!is_mhop) && (ttl != BFD_TTL_VAL)) { | |
853 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
854 | "invalid TTL: %d expected %d", ttl, BFD_TTL_VAL); | |
855 | return; | |
856 | } | |
857 | ||
858 | /* | |
859 | * Parse the control header for inconsistencies: | |
860 | * - Invalid version; | |
861 | * - Bad multiplier configuration; | |
862 | * - Short packets; | |
863 | * - Invalid discriminator; | |
864 | */ | |
865 | cp = (struct bfd_pkt *)(msgbuf); | |
866 | if (BFD_GETVER(cp->diag) != BFD_VERSION) { | |
867 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
868 | "bad version %d", BFD_GETVER(cp->diag)); | |
869 | return; | |
870 | } | |
871 | ||
872 | if (cp->detect_mult == 0) { | |
873 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
874 | "detect multiplier set to zero"); | |
875 | return; | |
876 | } | |
877 | ||
878 | if ((cp->len < BFD_PKT_LEN) || (cp->len > mlen)) { | |
879 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, "too small"); | |
880 | return; | |
881 | } | |
882 | ||
883 | if (cp->discrs.my_discr == 0) { | |
884 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
885 | "'my discriminator' is zero"); | |
886 | return; | |
887 | } | |
888 | ||
889 | /* Find the session that this packet belongs. */ | |
890 | bfd = ptm_bfd_sess_find(cp, &peer, &local, ifp, vrfid, is_mhop); | |
891 | if (bfd == NULL) { | |
892 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
893 | "no session found"); | |
894 | return; | |
895 | } | |
896 | /* | |
897 | * We may have a situation where received packet is on wrong vrf | |
898 | */ | |
899 | if (bfd && bfd->vrf && bfd->vrf != bvrf->vrf) { | |
900 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
901 | "wrong vrfid."); | |
902 | return; | |
903 | } | |
904 | ||
905 | /* Ensure that existing good sessions are not overridden. */ | |
906 | if (!cp->discrs.remote_discr && bfd->ses_state != PTM_BFD_DOWN && | |
907 | bfd->ses_state != PTM_BFD_ADM_DOWN) { | |
908 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
909 | "'remote discriminator' is zero, not overridden"); | |
910 | return; | |
911 | } | |
912 | ||
913 | /* | |
914 | * Multi hop: validate packet TTL. | |
915 | * Single hop: set local address that received the packet. | |
916 | * set peers mac address for echo packets | |
917 | */ | |
918 | if (is_mhop) { | |
919 | if (ttl < bfd->mh_ttl) { | |
920 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
921 | "exceeded max hop count (expected %d, got %d)", | |
922 | bfd->mh_ttl, ttl); | |
923 | return; | |
924 | } | |
925 | } else { | |
926 | ||
927 | if (bfd->local_address.sa_sin.sin_family == AF_UNSPEC) | |
928 | bfd->local_address = local; | |
929 | #ifdef BFD_LINUX | |
930 | if (ifp) | |
931 | bfd_peer_mac_set(sd, bfd, &peer, ifp); | |
932 | #endif | |
933 | } | |
934 | ||
935 | bfd->stats.rx_ctrl_pkt++; | |
936 | ||
937 | /* | |
938 | * If no interface was detected, save the interface where the | |
939 | * packet came in. | |
940 | */ | |
941 | if (!is_mhop && bfd->ifp == NULL) | |
942 | bfd->ifp = ifp; | |
943 | ||
944 | /* Log remote discriminator changes. */ | |
945 | if ((bfd->discrs.remote_discr != 0) | |
946 | && (bfd->discrs.remote_discr != ntohl(cp->discrs.my_discr))) | |
947 | cp_debug(is_mhop, &peer, &local, ifindex, vrfid, | |
948 | "remote discriminator mismatch (expected %u, got %u)", | |
949 | bfd->discrs.remote_discr, ntohl(cp->discrs.my_discr)); | |
950 | ||
951 | bfd->discrs.remote_discr = ntohl(cp->discrs.my_discr); | |
952 | ||
953 | /* Save remote diagnostics before state switch. */ | |
954 | bfd->remote_diag = cp->diag & BFD_DIAGMASK; | |
955 | ||
956 | /* Update remote timers settings. */ | |
957 | bfd->remote_timers.desired_min_tx = ntohl(cp->timers.desired_min_tx); | |
958 | bfd->remote_timers.required_min_rx = ntohl(cp->timers.required_min_rx); | |
959 | bfd->remote_timers.required_min_echo = | |
960 | ntohl(cp->timers.required_min_echo); | |
961 | bfd->remote_detect_mult = cp->detect_mult; | |
962 | ||
963 | if (BFD_GETCBIT(cp->flags)) | |
964 | bfd->remote_cbit = 1; | |
965 | else | |
966 | bfd->remote_cbit = 0; | |
967 | ||
968 | /* State switch from section 6.2. */ | |
969 | bs_state_handler(bfd, BFD_GETSTATE(cp->flags)); | |
970 | ||
971 | /* RFC 5880, Section 6.5: handle POLL/FINAL negotiation sequence. */ | |
972 | if (bfd->polling && BFD_GETFBIT(cp->flags)) { | |
973 | /* Disable polling. */ | |
974 | bfd->polling = 0; | |
975 | ||
976 | /* Handle poll finalization. */ | |
977 | bs_final_handler(bfd); | |
978 | } | |
979 | ||
980 | /* | |
981 | * Detection timeout calculation: | |
982 | * The minimum detection timeout is the remote detection | |
983 | * multipler (number of packets to be missed) times the agreed | |
984 | * transmission interval. | |
985 | * | |
986 | * RFC 5880, Section 6.8.4. | |
987 | */ | |
988 | if (bfd->cur_timers.required_min_rx > bfd->remote_timers.desired_min_tx) | |
989 | bfd->detect_TO = bfd->remote_detect_mult | |
990 | * bfd->cur_timers.required_min_rx; | |
991 | else | |
992 | bfd->detect_TO = bfd->remote_detect_mult | |
993 | * bfd->remote_timers.desired_min_tx; | |
994 | ||
995 | /* Apply new receive timer immediately. */ | |
996 | bfd_recvtimer_update(bfd); | |
997 | ||
998 | /* Handle echo timers changes. */ | |
999 | bs_echo_timer_handler(bfd); | |
1000 | ||
1001 | /* | |
1002 | * We've received a packet with the POLL bit set, we must send | |
1003 | * a control packet back with the FINAL bit set. | |
1004 | * | |
1005 | * RFC 5880, Section 6.5. | |
1006 | */ | |
1007 | if (BFD_GETPBIT(cp->flags)) { | |
1008 | /* We are finalizing a poll negotiation. */ | |
1009 | bs_final_handler(bfd); | |
1010 | ||
1011 | /* Send the control packet with the final bit immediately. */ | |
1012 | ptm_bfd_snd(bfd, 1); | |
1013 | } | |
1014 | } | |
1015 | ||
1016 | /* | |
1017 | * bp_bfd_echo_in: proccesses an BFD echo packet. On TTL == BFD_TTL_VAL | |
1018 | * the packet is looped back or returns the my discriminator ID along | |
1019 | * with the TTL. | |
1020 | * | |
1021 | * Returns -1 on error or loopback or 0 on success. | |
1022 | */ | |
1023 | int bp_bfd_echo_in(struct bfd_vrf_global *bvrf, int sd, uint8_t *ttl, | |
1024 | uint32_t *my_discr, uint64_t *my_rtt) | |
1025 | { | |
1026 | struct bfd_echo_pkt *bep; | |
1027 | ssize_t rlen; | |
1028 | struct sockaddr_any local, peer; | |
1029 | ifindex_t ifindex = IFINDEX_INTERNAL; | |
1030 | vrf_id_t vrfid = VRF_DEFAULT; | |
1031 | uint8_t msgbuf[1516]; | |
1032 | size_t bfd_offset = 0; | |
1033 | ||
1034 | if (sd == bvrf->bg_echo) { | |
1035 | #ifdef BFD_LINUX | |
1036 | rlen = bfd_recv_ipv4_fp(sd, msgbuf, sizeof(msgbuf), ttl, | |
1037 | &ifindex, &local, &peer); | |
1038 | ||
1039 | /* silently drop echo packet that is looped in fastpath but | |
1040 | * still comes up to BFD | |
1041 | */ | |
1042 | if (rlen == -1) | |
1043 | return -1; | |
1044 | bfd_offset = sizeof(struct udphdr) + sizeof(struct iphdr) + | |
1045 | sizeof(struct ethhdr); | |
1046 | #else | |
1047 | rlen = bfd_recv_ipv4(sd, msgbuf, sizeof(msgbuf), ttl, &ifindex, | |
1048 | &local, &peer); | |
1049 | bfd_offset = 0; | |
1050 | #endif | |
1051 | } else { | |
1052 | rlen = bfd_recv_ipv6(sd, msgbuf, sizeof(msgbuf), ttl, &ifindex, | |
1053 | &local, &peer); | |
1054 | bfd_offset = 0; | |
1055 | } | |
1056 | ||
1057 | /* Short packet, better not risk reading it. */ | |
1058 | if (rlen < (ssize_t)sizeof(*bep)) { | |
1059 | cp_debug(false, &peer, &local, ifindex, vrfid, | |
1060 | "small echo packet"); | |
1061 | return -1; | |
1062 | } | |
1063 | ||
1064 | /* Test for loopback for ipv6, ipv4 is looped in forwarding plane */ | |
1065 | if ((*ttl == BFD_TTL_VAL) && (sd == bvrf->bg_echov6)) { | |
1066 | bp_udp_send(sd, *ttl - 1, msgbuf, rlen, | |
1067 | (struct sockaddr *)&peer, | |
1068 | (sd == bvrf->bg_echo) ? sizeof(peer.sa_sin) | |
1069 | : sizeof(peer.sa_sin6)); | |
1070 | return -1; | |
1071 | } | |
1072 | ||
1073 | /* Read my discriminator from BFD Echo packet. */ | |
1074 | bep = (struct bfd_echo_pkt *)(msgbuf + bfd_offset); | |
1075 | *my_discr = ntohl(bep->my_discr); | |
1076 | if (*my_discr == 0) { | |
1077 | cp_debug(false, &peer, &local, ifindex, vrfid, | |
1078 | "invalid echo packet discriminator (zero)"); | |
1079 | return -1; | |
1080 | } | |
1081 | ||
1082 | #ifdef BFD_LINUX | |
1083 | /* RTT Calculation: determine RTT time of IPv4 echo pkt */ | |
1084 | if (sd == bvrf->bg_echo) { | |
1085 | struct timeval time_sent = {0, 0}; | |
1086 | ||
1087 | time_sent.tv_sec = be64toh(bep->time_sent_sec); | |
1088 | time_sent.tv_usec = be64toh(bep->time_sent_usec); | |
1089 | *my_rtt = monotime_since(&time_sent, NULL); | |
1090 | } | |
1091 | #endif | |
1092 | ||
1093 | return 0; | |
1094 | } | |
1095 | ||
1096 | #ifdef BFD_LINUX | |
1097 | /* | |
1098 | * send a bfd packet with src/dst same IP so that the peer will receive | |
1099 | * the packet and forward it back to sender in the forwarding plane | |
1100 | */ | |
1101 | int bp_udp_send_fp(int sd, uint8_t *data, size_t datalen, | |
1102 | struct bfd_session *bfd) | |
1103 | { | |
1104 | ssize_t wlen; | |
1105 | struct msghdr msg = {0}; | |
1106 | struct iovec iov[1]; | |
1107 | uint8_t msgctl[255]; | |
1108 | struct sockaddr_ll sadr_ll = {0}; | |
1109 | ||
1110 | sadr_ll.sll_ifindex = bfd->ifp->ifindex; | |
1111 | sadr_ll.sll_halen = ETH_ALEN; | |
1112 | memcpy(sadr_ll.sll_addr, bfd->peer_hw_addr, sizeof(bfd->peer_hw_addr)); | |
1113 | sadr_ll.sll_protocol = htons(ETH_P_IP); | |
1114 | ||
1115 | /* Prepare message data. */ | |
1116 | iov[0].iov_base = data; | |
1117 | iov[0].iov_len = datalen; | |
1118 | ||
1119 | memset(msgctl, 0, sizeof(msgctl)); | |
1120 | msg.msg_name = &sadr_ll; | |
1121 | msg.msg_namelen = sizeof(sadr_ll); | |
1122 | msg.msg_iov = iov; | |
1123 | msg.msg_iovlen = 1; | |
1124 | ||
1125 | /* Send echo to peer */ | |
1126 | wlen = sendmsg(sd, &msg, 0); | |
1127 | ||
1128 | if (wlen <= 0) { | |
1129 | if (bglobal.debug_network) | |
1130 | zlog_debug("%s: loopback failure: (%d) %s", __func__, | |
1131 | errno, strerror(errno)); | |
1132 | return -1; | |
1133 | } else if (wlen < (ssize_t)datalen) { | |
1134 | if (bglobal.debug_network) | |
1135 | zlog_debug("%s: partial send: %zd expected %zu", | |
1136 | __func__, wlen, datalen); | |
1137 | return -1; | |
1138 | } | |
1139 | ||
1140 | return 0; | |
1141 | } | |
1142 | #endif | |
1143 | ||
1144 | int bp_udp_send(int sd, uint8_t ttl, uint8_t *data, size_t datalen, | |
1145 | struct sockaddr *to, socklen_t tolen) | |
1146 | { | |
1147 | struct cmsghdr *cmsg; | |
1148 | ssize_t wlen; | |
1149 | int ttlval = ttl; | |
1150 | bool is_ipv6 = to->sa_family == AF_INET6; | |
1151 | struct msghdr msg; | |
1152 | struct iovec iov[1]; | |
1153 | uint8_t msgctl[255]; | |
1154 | ||
1155 | /* Prepare message data. */ | |
1156 | iov[0].iov_base = data; | |
1157 | iov[0].iov_len = datalen; | |
1158 | ||
1159 | memset(&msg, 0, sizeof(msg)); | |
1160 | memset(msgctl, 0, sizeof(msgctl)); | |
1161 | msg.msg_name = to; | |
1162 | msg.msg_namelen = tolen; | |
1163 | msg.msg_iov = iov; | |
1164 | msg.msg_iovlen = 1; | |
1165 | ||
1166 | /* Prepare the packet TTL information. */ | |
1167 | if (ttl > 0) { | |
1168 | /* Use ancillary data. */ | |
1169 | msg.msg_control = msgctl; | |
1170 | msg.msg_controllen = CMSG_LEN(sizeof(ttlval)); | |
1171 | ||
1172 | /* Configure the ancillary data. */ | |
1173 | cmsg = CMSG_FIRSTHDR(&msg); | |
1174 | cmsg->cmsg_len = CMSG_LEN(sizeof(ttlval)); | |
1175 | if (is_ipv6) { | |
1176 | cmsg->cmsg_level = IPPROTO_IPV6; | |
1177 | cmsg->cmsg_type = IPV6_HOPLIMIT; | |
1178 | } else { | |
1179 | #ifdef BFD_LINUX | |
1180 | cmsg->cmsg_level = IPPROTO_IP; | |
1181 | cmsg->cmsg_type = IP_TTL; | |
1182 | #else | |
1183 | /* FreeBSD does not support TTL in ancillary data. */ | |
1184 | msg.msg_control = NULL; | |
1185 | msg.msg_controllen = 0; | |
1186 | ||
1187 | bp_set_ttl(sd, ttl); | |
1188 | #endif /* BFD_BSD */ | |
1189 | } | |
1190 | memcpy(CMSG_DATA(cmsg), &ttlval, sizeof(ttlval)); | |
1191 | } | |
1192 | ||
1193 | /* Send echo back. */ | |
1194 | wlen = sendmsg(sd, &msg, 0); | |
1195 | if (wlen <= 0) { | |
1196 | if (bglobal.debug_network) | |
1197 | zlog_debug("%s: loopback failure: (%d) %s", __func__, | |
1198 | errno, strerror(errno)); | |
1199 | return -1; | |
1200 | } else if (wlen < (ssize_t)datalen) { | |
1201 | if (bglobal.debug_network) | |
1202 | zlog_debug("%s: partial send: %zd expected %zu", | |
1203 | __func__, wlen, datalen); | |
1204 | return -1; | |
1205 | } | |
1206 | ||
1207 | return 0; | |
1208 | } | |
1209 | ||
1210 | ||
1211 | /* | |
1212 | * Sockets creation. | |
1213 | */ | |
1214 | ||
1215 | ||
1216 | /* | |
1217 | * IPv4 sockets | |
1218 | */ | |
1219 | int bp_set_ttl(int sd, uint8_t value) | |
1220 | { | |
1221 | int ttl = value; | |
1222 | ||
1223 | if (setsockopt(sd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl)) == -1) { | |
1224 | zlog_warn("%s: setsockopt(IP_TTL, %d): %s", __func__, value, | |
1225 | strerror(errno)); | |
1226 | return -1; | |
1227 | } | |
1228 | ||
1229 | return 0; | |
1230 | } | |
1231 | ||
1232 | int bp_set_tos(int sd, uint8_t value) | |
1233 | { | |
1234 | int tos = value; | |
1235 | ||
1236 | if (setsockopt(sd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) == -1) { | |
1237 | zlog_warn("%s: setsockopt(IP_TOS, %d): %s", __func__, value, | |
1238 | strerror(errno)); | |
1239 | return -1; | |
1240 | } | |
1241 | ||
1242 | return 0; | |
1243 | } | |
1244 | ||
1245 | static bool bp_set_reuse_addr(int sd) | |
1246 | { | |
1247 | int one = 1; | |
1248 | ||
1249 | if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) == -1) { | |
1250 | zlog_warn("%s: setsockopt(SO_REUSEADDR, %d): %s", __func__, one, | |
1251 | strerror(errno)); | |
1252 | return false; | |
1253 | } | |
1254 | return true; | |
1255 | } | |
1256 | ||
1257 | static bool bp_set_reuse_port(int sd) | |
1258 | { | |
1259 | int one = 1; | |
1260 | ||
1261 | if (setsockopt(sd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)) == -1) { | |
1262 | zlog_warn("%s: setsockopt(SO_REUSEPORT, %d): %s", __func__, one, | |
1263 | strerror(errno)); | |
1264 | return false; | |
1265 | } | |
1266 | return true; | |
1267 | } | |
1268 | ||
1269 | ||
1270 | static void bp_set_ipopts(int sd) | |
1271 | { | |
1272 | int rcvttl = BFD_RCV_TTL_VAL; | |
1273 | ||
1274 | if (!bp_set_reuse_addr(sd)) | |
1275 | zlog_fatal("set-reuse-addr: failed"); | |
1276 | ||
1277 | if (!bp_set_reuse_port(sd)) | |
1278 | zlog_fatal("set-reuse-port: failed"); | |
1279 | ||
1280 | if (bp_set_ttl(sd, BFD_TTL_VAL) != 0) | |
1281 | zlog_fatal("set-ipopts: TTL configuration failed"); | |
1282 | ||
1283 | if (setsockopt(sd, IPPROTO_IP, IP_RECVTTL, &rcvttl, sizeof(rcvttl)) | |
1284 | == -1) | |
1285 | zlog_fatal("set-ipopts: setsockopt(IP_RECVTTL, %d): %s", rcvttl, | |
1286 | strerror(errno)); | |
1287 | ||
1288 | #ifdef BFD_LINUX | |
1289 | int pktinfo = BFD_PKT_INFO_VAL; | |
1290 | ||
1291 | /* Figure out address and interface to do the peer matching. */ | |
1292 | if (setsockopt(sd, IPPROTO_IP, IP_PKTINFO, &pktinfo, sizeof(pktinfo)) | |
1293 | == -1) | |
1294 | zlog_fatal("set-ipopts: setsockopt(IP_PKTINFO, %d): %s", | |
1295 | pktinfo, strerror(errno)); | |
1296 | #endif /* BFD_LINUX */ | |
1297 | #ifdef BFD_BSD | |
1298 | int yes = 1; | |
1299 | ||
1300 | /* Find out our address for peer matching. */ | |
1301 | if (setsockopt(sd, IPPROTO_IP, IP_RECVDSTADDR, &yes, sizeof(yes)) == -1) | |
1302 | zlog_fatal("set-ipopts: setsockopt(IP_RECVDSTADDR, %d): %s", | |
1303 | yes, strerror(errno)); | |
1304 | ||
1305 | /* Find out interface where the packet came in. */ | |
1306 | if (setsockopt_ifindex(AF_INET, sd, yes) == -1) | |
1307 | zlog_fatal("set-ipopts: setsockopt_ipv4_ifindex(%d): %s", yes, | |
1308 | strerror(errno)); | |
1309 | #endif /* BFD_BSD */ | |
1310 | } | |
1311 | ||
1312 | static void bp_bind_ip(int sd, uint16_t port) | |
1313 | { | |
1314 | struct sockaddr_in sin; | |
1315 | ||
1316 | memset(&sin, 0, sizeof(sin)); | |
1317 | sin.sin_family = AF_INET; | |
1318 | sin.sin_addr.s_addr = htonl(INADDR_ANY); | |
1319 | sin.sin_port = htons(port); | |
1320 | if (bind(sd, (struct sockaddr *)&sin, sizeof(sin)) == -1) | |
1321 | zlog_fatal("bind-ip: bind: %s", strerror(errno)); | |
1322 | } | |
1323 | ||
1324 | int bp_udp_shop(const struct vrf *vrf) | |
1325 | { | |
1326 | int sd; | |
1327 | ||
1328 | frr_with_privs(&bglobal.bfdd_privs) { | |
1329 | sd = vrf_socket(AF_INET, SOCK_DGRAM, PF_UNSPEC, vrf->vrf_id, | |
1330 | vrf->name); | |
1331 | } | |
1332 | if (sd == -1) | |
1333 | zlog_fatal("udp-shop: socket: %s", strerror(errno)); | |
1334 | ||
1335 | bp_set_ipopts(sd); | |
1336 | bp_bind_ip(sd, BFD_DEFDESTPORT); | |
1337 | return sd; | |
1338 | } | |
1339 | ||
1340 | int bp_udp_mhop(const struct vrf *vrf) | |
1341 | { | |
1342 | int sd; | |
1343 | ||
1344 | frr_with_privs(&bglobal.bfdd_privs) { | |
1345 | sd = vrf_socket(AF_INET, SOCK_DGRAM, PF_UNSPEC, vrf->vrf_id, | |
1346 | vrf->name); | |
1347 | } | |
1348 | if (sd == -1) | |
1349 | zlog_fatal("udp-mhop: socket: %s", strerror(errno)); | |
1350 | ||
1351 | bp_set_ipopts(sd); | |
1352 | bp_bind_ip(sd, BFD_DEF_MHOP_DEST_PORT); | |
1353 | ||
1354 | return sd; | |
1355 | } | |
1356 | ||
1357 | int bp_peer_socket(const struct bfd_session *bs) | |
1358 | { | |
1359 | int sd, pcount; | |
1360 | struct sockaddr_in sin; | |
1361 | static int srcPort = BFD_SRCPORTINIT; | |
1362 | const char *device_to_bind = NULL; | |
1363 | ||
1364 | if (bs->key.ifname[0]) | |
1365 | device_to_bind = (const char *)bs->key.ifname; | |
1366 | else if ((!vrf_is_backend_netns() && bs->vrf->vrf_id != VRF_DEFAULT) | |
1367 | || ((CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH) | |
1368 | && bs->key.vrfname[0]))) | |
1369 | device_to_bind = (const char *)bs->key.vrfname; | |
1370 | ||
1371 | frr_with_privs(&bglobal.bfdd_privs) { | |
1372 | sd = vrf_socket(AF_INET, SOCK_DGRAM, PF_UNSPEC, | |
1373 | bs->vrf->vrf_id, device_to_bind); | |
1374 | } | |
1375 | if (sd == -1) { | |
1376 | zlog_err("ipv4-new: failed to create socket: %s", | |
1377 | strerror(errno)); | |
1378 | return -1; | |
1379 | } | |
1380 | ||
1381 | /* Set TTL to 255 for all transmitted packets */ | |
1382 | if (bp_set_ttl(sd, BFD_TTL_VAL) != 0) { | |
1383 | close(sd); | |
1384 | return -1; | |
1385 | } | |
1386 | ||
1387 | /* Set TOS to CS6 for all transmitted packets */ | |
1388 | if (bp_set_tos(sd, BFD_TOS_VAL) != 0) { | |
1389 | close(sd); | |
1390 | return -1; | |
1391 | } | |
1392 | ||
1393 | /* Find an available source port in the proper range */ | |
1394 | memset(&sin, 0, sizeof(sin)); | |
1395 | sin.sin_family = AF_INET; | |
1396 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
1397 | sin.sin_len = sizeof(sin); | |
1398 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
1399 | memcpy(&sin.sin_addr, &bs->key.local, sizeof(sin.sin_addr)); | |
1400 | ||
1401 | pcount = 0; | |
1402 | do { | |
1403 | if ((++pcount) > (BFD_SRCPORTMAX - BFD_SRCPORTINIT)) { | |
1404 | /* Searched all ports, none available */ | |
1405 | zlog_err("ipv4-new: failed to bind port: %s", | |
1406 | strerror(errno)); | |
1407 | close(sd); | |
1408 | return -1; | |
1409 | } | |
1410 | if (srcPort >= BFD_SRCPORTMAX) | |
1411 | srcPort = BFD_SRCPORTINIT; | |
1412 | sin.sin_port = htons(srcPort++); | |
1413 | } while (bind(sd, (struct sockaddr *)&sin, sizeof(sin)) < 0); | |
1414 | ||
1415 | return sd; | |
1416 | } | |
1417 | ||
1418 | ||
1419 | /* | |
1420 | * IPv6 sockets | |
1421 | */ | |
1422 | ||
1423 | int bp_peer_socketv6(const struct bfd_session *bs) | |
1424 | { | |
1425 | int sd, pcount; | |
1426 | struct sockaddr_in6 sin6; | |
1427 | static int srcPort = BFD_SRCPORTINIT; | |
1428 | const char *device_to_bind = NULL; | |
1429 | ||
1430 | if (bs->key.ifname[0]) | |
1431 | device_to_bind = (const char *)bs->key.ifname; | |
1432 | else if ((!vrf_is_backend_netns() && bs->vrf->vrf_id != VRF_DEFAULT) | |
1433 | || ((CHECK_FLAG(bs->flags, BFD_SESS_FLAG_MH) | |
1434 | && bs->key.vrfname[0]))) | |
1435 | device_to_bind = (const char *)bs->key.vrfname; | |
1436 | ||
1437 | frr_with_privs(&bglobal.bfdd_privs) { | |
1438 | sd = vrf_socket(AF_INET6, SOCK_DGRAM, PF_UNSPEC, | |
1439 | bs->vrf->vrf_id, device_to_bind); | |
1440 | } | |
1441 | if (sd == -1) { | |
1442 | zlog_err("ipv6-new: failed to create socket: %s", | |
1443 | strerror(errno)); | |
1444 | return -1; | |
1445 | } | |
1446 | ||
1447 | /* Set TTL to 255 for all transmitted packets */ | |
1448 | if (bp_set_ttlv6(sd, BFD_TTL_VAL) != 0) { | |
1449 | close(sd); | |
1450 | return -1; | |
1451 | } | |
1452 | ||
1453 | /* Set TOS to CS6 for all transmitted packets */ | |
1454 | if (bp_set_tosv6(sd, BFD_TOS_VAL) != 0) { | |
1455 | close(sd); | |
1456 | return -1; | |
1457 | } | |
1458 | ||
1459 | /* Find an available source port in the proper range */ | |
1460 | memset(&sin6, 0, sizeof(sin6)); | |
1461 | sin6.sin6_family = AF_INET6; | |
1462 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
1463 | sin6.sin6_len = sizeof(sin6); | |
1464 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
1465 | memcpy(&sin6.sin6_addr, &bs->key.local, sizeof(sin6.sin6_addr)); | |
1466 | if (bs->ifp && IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr)) | |
1467 | sin6.sin6_scope_id = bs->ifp->ifindex; | |
1468 | ||
1469 | pcount = 0; | |
1470 | do { | |
1471 | if ((++pcount) > (BFD_SRCPORTMAX - BFD_SRCPORTINIT)) { | |
1472 | /* Searched all ports, none available */ | |
1473 | zlog_err("ipv6-new: failed to bind port: %s", | |
1474 | strerror(errno)); | |
1475 | close(sd); | |
1476 | return -1; | |
1477 | } | |
1478 | if (srcPort >= BFD_SRCPORTMAX) | |
1479 | srcPort = BFD_SRCPORTINIT; | |
1480 | sin6.sin6_port = htons(srcPort++); | |
1481 | } while (bind(sd, (struct sockaddr *)&sin6, sizeof(sin6)) < 0); | |
1482 | ||
1483 | return sd; | |
1484 | } | |
1485 | ||
1486 | int bp_set_ttlv6(int sd, uint8_t value) | |
1487 | { | |
1488 | int ttl = value; | |
1489 | ||
1490 | if (setsockopt(sd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)) | |
1491 | == -1) { | |
1492 | zlog_warn("set-ttlv6: setsockopt(IPV6_UNICAST_HOPS, %d): %s", | |
1493 | value, strerror(errno)); | |
1494 | return -1; | |
1495 | } | |
1496 | ||
1497 | return 0; | |
1498 | } | |
1499 | ||
1500 | int bp_set_tosv6(int sd, uint8_t value) | |
1501 | { | |
1502 | int tos = value; | |
1503 | ||
1504 | if (setsockopt(sd, IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) | |
1505 | == -1) { | |
1506 | zlog_warn("set-tosv6: setsockopt(IPV6_TCLASS, %d): %s", value, | |
1507 | strerror(errno)); | |
1508 | return -1; | |
1509 | } | |
1510 | ||
1511 | return 0; | |
1512 | } | |
1513 | ||
1514 | static void bp_set_ipv6opts(int sd) | |
1515 | { | |
1516 | int ipv6_pktinfo = BFD_IPV6_PKT_INFO_VAL; | |
1517 | int ipv6_only = BFD_IPV6_ONLY_VAL; | |
1518 | ||
1519 | if (!bp_set_reuse_addr(sd)) | |
1520 | zlog_fatal("set-reuse-addr: failed"); | |
1521 | ||
1522 | if (!bp_set_reuse_port(sd)) | |
1523 | zlog_fatal("set-reuse-port: failed"); | |
1524 | ||
1525 | if (bp_set_ttlv6(sd, BFD_TTL_VAL) == -1) | |
1526 | zlog_fatal( | |
1527 | "set-ipv6opts: setsockopt(IPV6_UNICAST_HOPS, %d): %s", | |
1528 | BFD_TTL_VAL, strerror(errno)); | |
1529 | ||
1530 | if (setsockopt_ipv6_hoplimit(sd, BFD_RCV_TTL_VAL) == -1) | |
1531 | zlog_fatal("set-ipv6opts: setsockopt(IPV6_HOPLIMIT, %d): %s", | |
1532 | BFD_RCV_TTL_VAL, strerror(errno)); | |
1533 | ||
1534 | if (setsockopt_ipv6_pktinfo(sd, ipv6_pktinfo) == -1) | |
1535 | zlog_fatal("set-ipv6opts: setsockopt(IPV6_PKTINFO, %d): %s", | |
1536 | ipv6_pktinfo, strerror(errno)); | |
1537 | ||
1538 | if (setsockopt(sd, IPPROTO_IPV6, IPV6_V6ONLY, &ipv6_only, | |
1539 | sizeof(ipv6_only)) | |
1540 | == -1) | |
1541 | zlog_fatal("set-ipv6opts: setsockopt(IPV6_V6ONLY, %d): %s", | |
1542 | ipv6_only, strerror(errno)); | |
1543 | } | |
1544 | ||
1545 | static void bp_bind_ipv6(int sd, uint16_t port) | |
1546 | { | |
1547 | struct sockaddr_in6 sin6; | |
1548 | ||
1549 | memset(&sin6, 0, sizeof(sin6)); | |
1550 | sin6.sin6_family = AF_INET6; | |
1551 | sin6.sin6_addr = in6addr_any; | |
1552 | sin6.sin6_port = htons(port); | |
1553 | #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN | |
1554 | sin6.sin6_len = sizeof(sin6); | |
1555 | #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */ | |
1556 | if (bind(sd, (struct sockaddr *)&sin6, sizeof(sin6)) == -1) | |
1557 | zlog_fatal("bind-ipv6: bind: %s", strerror(errno)); | |
1558 | } | |
1559 | ||
1560 | int bp_udp6_shop(const struct vrf *vrf) | |
1561 | { | |
1562 | int sd; | |
1563 | ||
1564 | frr_with_privs(&bglobal.bfdd_privs) { | |
1565 | sd = vrf_socket(AF_INET6, SOCK_DGRAM, PF_UNSPEC, vrf->vrf_id, | |
1566 | vrf->name); | |
1567 | } | |
1568 | if (sd == -1) { | |
1569 | if (errno != EAFNOSUPPORT) | |
1570 | zlog_fatal("udp6-shop: socket: %s", strerror(errno)); | |
1571 | else | |
1572 | zlog_warn("udp6-shop: V6 is not supported, continuing"); | |
1573 | ||
1574 | return -1; | |
1575 | } | |
1576 | ||
1577 | bp_set_ipv6opts(sd); | |
1578 | bp_bind_ipv6(sd, BFD_DEFDESTPORT); | |
1579 | ||
1580 | return sd; | |
1581 | } | |
1582 | ||
1583 | int bp_udp6_mhop(const struct vrf *vrf) | |
1584 | { | |
1585 | int sd; | |
1586 | ||
1587 | frr_with_privs(&bglobal.bfdd_privs) { | |
1588 | sd = vrf_socket(AF_INET6, SOCK_DGRAM, PF_UNSPEC, vrf->vrf_id, | |
1589 | vrf->name); | |
1590 | } | |
1591 | if (sd == -1) { | |
1592 | if (errno != EAFNOSUPPORT) | |
1593 | zlog_fatal("udp6-mhop: socket: %s", strerror(errno)); | |
1594 | else | |
1595 | zlog_warn("udp6-mhop: V6 is not supported, continuing"); | |
1596 | ||
1597 | return -1; | |
1598 | } | |
1599 | ||
1600 | bp_set_ipv6opts(sd); | |
1601 | bp_bind_ipv6(sd, BFD_DEF_MHOP_DEST_PORT); | |
1602 | ||
1603 | return sd; | |
1604 | } | |
1605 | ||
1606 | #ifdef BFD_LINUX | |
1607 | /* tcpdump -dd udp dst port 3785 */ | |
1608 | struct sock_filter my_filterudp[] = { | |
1609 | {0x28, 0, 0, 0x0000000c}, {0x15, 0, 8, 0x00000800}, | |
1610 | {0x30, 0, 0, 0x00000017}, {0x15, 0, 6, 0x00000011}, | |
1611 | {0x28, 0, 0, 0x00000014}, {0x45, 4, 0, 0x00001fff}, | |
1612 | {0xb1, 0, 0, 0x0000000e}, {0x48, 0, 0, 0x00000010}, | |
1613 | {0x15, 0, 1, 0x00000ec9}, {0x6, 0, 0, 0x00040000}, | |
1614 | {0x6, 0, 0, 0x00000000}, | |
1615 | }; | |
1616 | ||
1617 | #define MY_FILTER_LENGTH 11 | |
1618 | ||
1619 | int bp_echo_socket(const struct vrf *vrf) | |
1620 | { | |
1621 | int s; | |
1622 | ||
1623 | frr_with_privs (&bglobal.bfdd_privs) { | |
1624 | s = vrf_socket(AF_PACKET, SOCK_RAW, ETH_P_IP, vrf->vrf_id, | |
1625 | vrf->name); | |
1626 | } | |
1627 | ||
1628 | if (s == -1) | |
1629 | zlog_fatal("echo-socket: socket: %s", strerror(errno)); | |
1630 | ||
1631 | struct sock_fprog pf; | |
1632 | struct sockaddr_ll sll = {0}; | |
1633 | ||
1634 | /* adjust filter for socket to only receive ECHO packets */ | |
1635 | pf.filter = my_filterudp; | |
1636 | pf.len = MY_FILTER_LENGTH; | |
1637 | if (setsockopt(s, SOL_SOCKET, SO_ATTACH_FILTER, &pf, sizeof(pf)) == | |
1638 | -1) { | |
1639 | zlog_warn("%s: setsockopt(SO_ATTACH_FILTER): %s", __func__, | |
1640 | strerror(errno)); | |
1641 | close(s); | |
1642 | return -1; | |
1643 | } | |
1644 | ||
1645 | memset(&sll, 0, sizeof(sll)); | |
1646 | sll.sll_family = AF_PACKET; | |
1647 | sll.sll_protocol = htons(ETH_P_IP); | |
1648 | sll.sll_ifindex = 0; | |
1649 | if (bind(s, (struct sockaddr *)&sll, sizeof(sll)) < 0) { | |
1650 | zlog_warn("Failed to bind echo socket: %s", | |
1651 | safe_strerror(errno)); | |
1652 | close(s); | |
1653 | return -1; | |
1654 | } | |
1655 | ||
1656 | return s; | |
1657 | } | |
1658 | #else | |
1659 | int bp_echo_socket(const struct vrf *vrf) | |
1660 | { | |
1661 | int s; | |
1662 | ||
1663 | frr_with_privs(&bglobal.bfdd_privs) { | |
1664 | s = vrf_socket(AF_INET, SOCK_DGRAM, 0, vrf->vrf_id, vrf->name); | |
1665 | } | |
1666 | if (s == -1) | |
1667 | zlog_fatal("echo-socket: socket: %s", strerror(errno)); | |
1668 | ||
1669 | bp_set_ipopts(s); | |
1670 | bp_bind_ip(s, BFD_DEF_ECHO_PORT); | |
1671 | ||
1672 | return s; | |
1673 | } | |
1674 | #endif | |
1675 | ||
1676 | int bp_echov6_socket(const struct vrf *vrf) | |
1677 | { | |
1678 | int s; | |
1679 | ||
1680 | frr_with_privs(&bglobal.bfdd_privs) { | |
1681 | s = vrf_socket(AF_INET6, SOCK_DGRAM, 0, vrf->vrf_id, vrf->name); | |
1682 | } | |
1683 | if (s == -1) { | |
1684 | if (errno != EAFNOSUPPORT) | |
1685 | zlog_fatal("echov6-socket: socket: %s", | |
1686 | strerror(errno)); | |
1687 | else | |
1688 | zlog_warn("echov6-socket: V6 is not supported, continuing"); | |
1689 | ||
1690 | return -1; | |
1691 | } | |
1692 | ||
1693 | bp_set_ipv6opts(s); | |
1694 | bp_bind_ipv6(s, BFD_DEF_ECHO_PORT); | |
1695 | ||
1696 | return s; | |
1697 | } | |
1698 | ||
1699 | #ifdef BFD_LINUX | |
1700 | /* get peer's mac address to be used with Echo packets when they are looped in | |
1701 | * peers forwarding plane | |
1702 | */ | |
1703 | void bfd_peer_mac_set(int sd, struct bfd_session *bfd, | |
1704 | struct sockaddr_any *peer, struct interface *ifp) | |
1705 | { | |
1706 | struct arpreq arpreq_; | |
1707 | ||
1708 | if (CHECK_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET)) | |
1709 | return; | |
1710 | if (ifp->flags & IFF_NOARP) | |
1711 | return; | |
1712 | ||
1713 | if (peer->sa_sin.sin_family == AF_INET) { | |
1714 | /* IPV4 */ | |
1715 | struct sockaddr_in *addr = | |
1716 | (struct sockaddr_in *)&arpreq_.arp_pa; | |
1717 | ||
1718 | memset(&arpreq_, 0, sizeof(struct arpreq)); | |
1719 | addr->sin_family = AF_INET; | |
1720 | memcpy(&addr->sin_addr.s_addr, &peer->sa_sin.sin_addr, | |
1721 | sizeof(addr->sin_addr)); | |
1722 | strlcpy(arpreq_.arp_dev, ifp->name, sizeof(arpreq_.arp_dev)); | |
1723 | ||
1724 | if (ioctl(sd, SIOCGARP, &arpreq_) < 0) { | |
1725 | zlog_warn( | |
1726 | "BFD: getting peer's mac on %s failed error %s", | |
1727 | ifp->name, strerror(errno)); | |
1728 | UNSET_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET); | |
1729 | memset(bfd->peer_hw_addr, 0, sizeof(bfd->peer_hw_addr)); | |
1730 | ||
1731 | } else { | |
1732 | memcpy(bfd->peer_hw_addr, arpreq_.arp_ha.sa_data, | |
1733 | sizeof(bfd->peer_hw_addr)); | |
1734 | SET_FLAG(bfd->flags, BFD_SESS_FLAG_MAC_SET); | |
1735 | } | |
1736 | } | |
1737 | } | |
1738 | #endif |