1 /*********************************************************************
2 * Copyright 2017 Cumulus Networks, Inc. All rights reserved.
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)
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
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
18 * bfd_packet.c: implements the BFD protocol packet handling.
22 * Shrijeet Mukherjee [shm@cumulusnetworks.com]
23 * Kanna Rajagopal [kanna@cumulusnetworks.com]
24 * Radhika Mahankali [Radhika@cumulusnetworks.com]
30 #include <linux/if_packet.h>
31 #endif /* BFD_LINUX */
33 #include <netinet/if_ether.h>
34 #include <netinet/udp.h>
36 #include "lib/sockopt.h"
44 static int ptm_bfd_process_echo_pkt(int s
);
45 int _ptm_bfd_send(struct bfd_session
*bs
, uint16_t *port
, const void *data
,
48 static void bfd_sd_reschedule(int sd
);
49 ssize_t
bfd_recv_ipv4(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
50 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
51 struct sockaddr_any
*peer
);
52 ssize_t
bfd_recv_ipv6(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
53 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
54 struct sockaddr_any
*peer
);
55 int bp_udp_send(int sd
, uint8_t ttl
, uint8_t *data
, size_t datalen
,
56 struct sockaddr
*to
, socklen_t tolen
);
57 int bp_bfd_echo_in(int sd
, uint8_t *ttl
, uint32_t *my_discr
);
59 /* socket related prototypes */
60 static void bp_set_ipopts(int sd
);
61 static void bp_bind_ip(int sd
, uint16_t port
);
62 static void bp_set_ipv6opts(int sd
);
63 static void bp_bind_ipv6(int sd
, uint16_t port
);
69 int _ptm_bfd_send(struct bfd_session
*bs
, uint16_t *port
, const void *data
,
73 struct sockaddr_in sin
;
74 struct sockaddr_in6 sin6
;
79 if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_IPV6
)) {
80 memset(&sin6
, 0, sizeof(sin6
));
81 sin6
.sin6_family
= AF_INET6
;
82 memcpy(&sin6
.sin6_addr
, &bs
->key
.peer
, sizeof(sin6
.sin6_addr
));
83 if (IN6_IS_ADDR_LINKLOCAL(&sin6
.sin6_addr
))
84 sin6
.sin6_scope_id
= bs
->ifp
->ifindex
;
88 : (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
))
89 ? htons(BFD_DEF_MHOP_DEST_PORT
)
90 : htons(BFD_DEFDESTPORT
);
93 sa
= (struct sockaddr
*)&sin6
;
96 memset(&sin
, 0, sizeof(sin
));
97 sin
.sin_family
= AF_INET
;
98 memcpy(&sin
.sin_addr
, &bs
->key
.peer
, sizeof(sin
.sin_addr
));
101 : (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
))
102 ? htons(BFD_DEF_MHOP_DEST_PORT
)
103 : htons(BFD_DEFDESTPORT
);
106 sa
= (struct sockaddr
*)&sin
;
110 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
112 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
113 rv
= sendto(sd
, data
, datalen
, 0, sa
, slen
);
115 log_debug("packet-send: send failure: %s", strerror(errno
));
118 if (rv
< (ssize_t
)datalen
)
119 log_debug("packet-send: send partial", strerror(errno
));
124 void ptm_bfd_echo_snd(struct bfd_session
*bfd
)
129 struct bfd_echo_pkt bep
;
130 struct sockaddr_in sin
;
131 struct sockaddr_in6 sin6
;
133 if (!BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_ECHO_ACTIVE
))
134 BFD_SET_FLAG(bfd
->flags
, BFD_SESS_FLAG_ECHO_ACTIVE
);
136 memset(&bep
, 0, sizeof(bep
));
137 bep
.ver
= BFD_ECHO_VERSION
;
138 bep
.len
= BFD_ECHO_PKT_LEN
;
139 bep
.my_discr
= htonl(bfd
->discrs
.my_discr
);
141 if (BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_IPV6
)) {
142 sd
= bglobal
.bg_echov6
;
143 memset(&sin6
, 0, sizeof(sin6
));
144 sin6
.sin6_family
= AF_INET6
;
145 memcpy(&sin6
.sin6_addr
, &bfd
->key
.peer
, sizeof(sin6
.sin6_addr
));
146 if (bfd
->ifp
&& IN6_IS_ADDR_LINKLOCAL(&sin6
.sin6_addr
))
147 sin6
.sin6_scope_id
= bfd
->ifp
->ifindex
;
149 sin6
.sin6_port
= htons(BFD_DEF_ECHO_PORT
);
150 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
151 sin6
.sin6_len
= sizeof(sin6
);
152 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
154 sa
= (struct sockaddr
*)&sin6
;
155 salen
= sizeof(sin6
);
157 sd
= bglobal
.bg_echo
;
158 memset(&sin6
, 0, sizeof(sin6
));
159 sin
.sin_family
= AF_INET
;
160 memcpy(&sin
.sin_addr
, &bfd
->key
.peer
, sizeof(sin
.sin_addr
));
161 sin
.sin_port
= htons(BFD_DEF_ECHO_PORT
);
162 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
163 sin
.sin_len
= sizeof(sin
);
164 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
166 sa
= (struct sockaddr
*)&sin
;
169 if (bp_udp_send(sd
, BFD_TTL_VAL
, (uint8_t *)&bep
, sizeof(bep
), sa
,
174 bfd
->stats
.tx_echo_pkt
++;
177 static int ptm_bfd_process_echo_pkt(int s
)
179 struct bfd_session
*bfd
;
180 uint32_t my_discr
= 0;
183 /* Receive and parse echo packet. */
184 if (bp_bfd_echo_in(s
, &ttl
, &my_discr
) == -1)
187 /* Your discriminator not zero - use it to find session */
188 bfd
= bfd_id_lookup(my_discr
);
190 log_debug("echo-packet: no matching session (id:%u)", my_discr
);
194 if (!BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_ECHO_ACTIVE
)) {
195 log_debug("echo-packet: echo disabled [%s] (id:%u)",
196 bs_to_string(bfd
), my_discr
);
200 bfd
->stats
.rx_echo_pkt
++;
202 /* Compute detect time */
203 bfd
->echo_detect_TO
= bfd
->remote_detect_mult
* bfd
->echo_xmt_TO
;
205 /* Update echo receive timeout. */
206 if (bfd
->echo_detect_TO
> 0)
207 bfd_echo_recvtimer_update(bfd
);
212 void ptm_bfd_snd(struct bfd_session
*bfd
, int fbit
)
216 /* Set fields according to section 6.5.7 */
217 cp
.diag
= bfd
->local_diag
;
218 BFD_SETVER(cp
.diag
, BFD_VERSION
);
220 BFD_SETSTATE(cp
.flags
, bfd
->ses_state
);
221 BFD_SETDEMANDBIT(cp
.flags
, BFD_DEF_DEMAND
);
224 * Polling and Final can't be set at the same time.
226 * RFC 5880, Section 6.5.
228 BFD_SETFBIT(cp
.flags
, fbit
);
230 BFD_SETPBIT(cp
.flags
, bfd
->polling
);
232 cp
.detect_mult
= bfd
->detect_mult
;
233 cp
.len
= BFD_PKT_LEN
;
234 cp
.discrs
.my_discr
= htonl(bfd
->discrs
.my_discr
);
235 cp
.discrs
.remote_discr
= htonl(bfd
->discrs
.remote_discr
);
237 cp
.timers
.desired_min_tx
=
238 htonl(bfd
->timers
.desired_min_tx
);
239 cp
.timers
.required_min_rx
=
240 htonl(bfd
->timers
.required_min_rx
);
243 * We can only announce current setting on poll, this
244 * avoids timing mismatch with our peer and give it
245 * the oportunity to learn. See `bs_final_handler` for
248 cp
.timers
.desired_min_tx
=
249 htonl(bfd
->cur_timers
.desired_min_tx
);
250 cp
.timers
.required_min_rx
=
251 htonl(bfd
->cur_timers
.required_min_rx
);
253 cp
.timers
.required_min_echo
= htonl(bfd
->timers
.required_min_echo
);
255 if (_ptm_bfd_send(bfd
, NULL
, &cp
, BFD_PKT_LEN
) != 0)
258 bfd
->stats
.tx_ctrl_pkt
++;
261 ssize_t
bfd_recv_ipv4(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
262 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
263 struct sockaddr_any
*peer
)
267 struct sockaddr_in msgaddr
;
268 struct msghdr msghdr
;
270 uint8_t cmsgbuf
[255];
272 /* Prepare the recvmsg params. */
273 iov
[0].iov_base
= msgbuf
;
274 iov
[0].iov_len
= msgbuflen
;
276 memset(&msghdr
, 0, sizeof(msghdr
));
277 msghdr
.msg_name
= &msgaddr
;
278 msghdr
.msg_namelen
= sizeof(msgaddr
);
279 msghdr
.msg_iov
= iov
;
280 msghdr
.msg_iovlen
= 1;
281 msghdr
.msg_control
= cmsgbuf
;
282 msghdr
.msg_controllen
= sizeof(cmsgbuf
);
284 mlen
= recvmsg(sd
, &msghdr
, MSG_DONTWAIT
);
287 log_error("ipv4-recv: recv failed: %s",
293 /* Get source address */
294 peer
->sa_sin
= *((struct sockaddr_in
*)(msghdr
.msg_name
));
296 /* Get and check TTL */
297 for (cm
= CMSG_FIRSTHDR(&msghdr
); cm
!= NULL
;
298 cm
= CMSG_NXTHDR(&msghdr
, cm
)) {
299 if (cm
->cmsg_level
!= IPPROTO_IP
)
302 switch (cm
->cmsg_type
) {
307 memcpy(&ttlval
, CMSG_DATA(cm
), sizeof(ttlval
));
309 log_debug("ipv4-recv: invalid TTL: %u", ttlval
);
317 struct in_pktinfo
*pi
=
318 (struct in_pktinfo
*)CMSG_DATA(cm
);
323 local
->sa_sin
.sin_family
= AF_INET
;
324 local
->sa_sin
.sin_addr
= pi
->ipi_addr
;
325 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
326 local
->sa_sin
.sin_len
= sizeof(local
->sa_sin
);
327 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
329 *ifindex
= pi
->ipi_ifindex
;
332 #endif /* BFD_LINUX */
335 memcpy(ttl
, CMSG_DATA(cm
), sizeof(*ttl
));
339 case IP_RECVDSTADDR
: {
342 memcpy(&ia
, CMSG_DATA(cm
), sizeof(ia
));
343 local
->sa_sin
.sin_family
= AF_INET
;
344 local
->sa_sin
.sin_addr
= ia
;
345 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
346 local
->sa_sin
.sin_len
= sizeof(local
->sa_sin
);
347 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
354 * On *BSDs we expect to land here when skipping
355 * the IP_RECVIF header. It will be handled by
356 * getsockopt_ifindex() below.
363 /* OS agnostic way of getting interface name. */
364 if (*ifindex
== IFINDEX_INTERNAL
)
365 *ifindex
= getsockopt_ifindex(AF_INET
, &msghdr
);
370 ssize_t
bfd_recv_ipv6(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
371 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
372 struct sockaddr_any
*peer
)
375 struct in6_pktinfo
*pi6
= NULL
;
378 struct sockaddr_in6 msgaddr6
;
379 struct msghdr msghdr6
;
381 uint8_t cmsgbuf6
[255];
383 /* Prepare the recvmsg params. */
384 iov
[0].iov_base
= msgbuf
;
385 iov
[0].iov_len
= msgbuflen
;
387 memset(&msghdr6
, 0, sizeof(msghdr6
));
388 msghdr6
.msg_name
= &msgaddr6
;
389 msghdr6
.msg_namelen
= sizeof(msgaddr6
);
390 msghdr6
.msg_iov
= iov
;
391 msghdr6
.msg_iovlen
= 1;
392 msghdr6
.msg_control
= cmsgbuf6
;
393 msghdr6
.msg_controllen
= sizeof(cmsgbuf6
);
395 mlen
= recvmsg(sd
, &msghdr6
, MSG_DONTWAIT
);
398 log_error("ipv6-recv: recv failed: %s",
404 /* Get source address */
405 peer
->sa_sin6
= *((struct sockaddr_in6
*)(msghdr6
.msg_name
));
407 /* Get and check TTL */
408 for (cm
= CMSG_FIRSTHDR(&msghdr6
); cm
!= NULL
;
409 cm
= CMSG_NXTHDR(&msghdr6
, cm
)) {
410 if (cm
->cmsg_level
!= IPPROTO_IPV6
)
413 if (cm
->cmsg_type
== IPV6_HOPLIMIT
) {
414 memcpy(&ttlval
, CMSG_DATA(cm
), sizeof(ttlval
));
416 log_debug("ipv6-recv: invalid TTL: %u", ttlval
);
421 } else if (cm
->cmsg_type
== IPV6_PKTINFO
) {
422 pi6
= (struct in6_pktinfo
*)CMSG_DATA(cm
);
424 local
->sa_sin6
.sin6_family
= AF_INET6
;
425 local
->sa_sin6
.sin6_addr
= pi6
->ipi6_addr
;
426 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
427 local
->sa_sin6
.sin6_len
= sizeof(local
->sa_sin6
);
428 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
430 *ifindex
= pi6
->ipi6_ifindex
;
435 /* Set scope ID for link local addresses. */
436 if (IN6_IS_ADDR_LINKLOCAL(&peer
->sa_sin6
.sin6_addr
))
437 peer
->sa_sin6
.sin6_scope_id
= *ifindex
;
438 if (IN6_IS_ADDR_LINKLOCAL(&local
->sa_sin6
.sin6_addr
))
439 local
->sa_sin6
.sin6_scope_id
= *ifindex
;
444 static void bfd_sd_reschedule(int sd
)
446 if (sd
== bglobal
.bg_shop
) {
447 THREAD_OFF(bglobal
.bg_ev
[0]);
448 thread_add_read(master
, bfd_recv_cb
, NULL
, bglobal
.bg_shop
,
450 } else if (sd
== bglobal
.bg_mhop
) {
451 THREAD_OFF(bglobal
.bg_ev
[1]);
452 thread_add_read(master
, bfd_recv_cb
, NULL
, bglobal
.bg_mhop
,
454 } else if (sd
== bglobal
.bg_shop6
) {
455 THREAD_OFF(bglobal
.bg_ev
[2]);
456 thread_add_read(master
, bfd_recv_cb
, NULL
, bglobal
.bg_shop6
,
458 } else if (sd
== bglobal
.bg_mhop6
) {
459 THREAD_OFF(bglobal
.bg_ev
[3]);
460 thread_add_read(master
, bfd_recv_cb
, NULL
, bglobal
.bg_mhop6
,
462 } else if (sd
== bglobal
.bg_echo
) {
463 THREAD_OFF(bglobal
.bg_ev
[4]);
464 thread_add_read(master
, bfd_recv_cb
, NULL
, bglobal
.bg_echo
,
466 } else if (sd
== bglobal
.bg_echov6
) {
467 THREAD_OFF(bglobal
.bg_ev
[5]);
468 thread_add_read(master
, bfd_recv_cb
, NULL
, bglobal
.bg_echov6
,
473 static void cp_debug(bool mhop
, struct sockaddr_any
*peer
,
474 struct sockaddr_any
*local
, ifindex_t ifindex
,
475 vrf_id_t vrfid
, const char *fmt
, ...)
477 char buf
[512], peerstr
[128], localstr
[128], portstr
[64], vrfstr
[64];
480 if (peer
->sa_sin
.sin_family
)
481 snprintf(peerstr
, sizeof(peerstr
), " peer:%s", satostr(peer
));
485 if (local
->sa_sin
.sin_family
)
486 snprintf(localstr
, sizeof(localstr
), " local:%s",
491 if (ifindex
!= IFINDEX_INTERNAL
)
492 snprintf(portstr
, sizeof(portstr
), " port:%u", ifindex
);
496 if (vrfid
!= VRF_DEFAULT
)
497 snprintf(vrfstr
, sizeof(vrfstr
), " vrf:%u", vrfid
);
502 vsnprintf(buf
, sizeof(buf
), fmt
, vl
);
505 log_debug("control-packet: %s [mhop:%s%s%s%s%s]", buf
,
506 mhop
? "yes" : "no", peerstr
, localstr
, portstr
, vrfstr
);
509 int bfd_recv_cb(struct thread
*t
)
511 int sd
= THREAD_FD(t
);
512 struct bfd_session
*bfd
;
517 vrf_id_t vrfid
= VRF_DEFAULT
;
518 ifindex_t ifindex
= IFINDEX_INTERNAL
;
519 struct sockaddr_any local
, peer
;
520 uint8_t msgbuf
[1516];
522 /* Schedule next read. */
523 bfd_sd_reschedule(sd
);
525 /* Handle echo packets. */
526 if (sd
== bglobal
.bg_echo
|| sd
== bglobal
.bg_echov6
) {
527 ptm_bfd_process_echo_pkt(sd
);
531 /* Sanitize input/output. */
532 memset(&local
, 0, sizeof(local
));
533 memset(&peer
, 0, sizeof(peer
));
535 /* Handle control packets. */
537 if (sd
== bglobal
.bg_shop
|| sd
== bglobal
.bg_mhop
) {
538 is_mhop
= sd
== bglobal
.bg_mhop
;
539 mlen
= bfd_recv_ipv4(sd
, msgbuf
, sizeof(msgbuf
), &ttl
, &ifindex
,
541 } else if (sd
== bglobal
.bg_shop6
|| sd
== bglobal
.bg_mhop6
) {
542 is_mhop
= sd
== bglobal
.bg_mhop6
;
543 mlen
= bfd_recv_ipv6(sd
, msgbuf
, sizeof(msgbuf
), &ttl
, &ifindex
,
547 /* Implement RFC 5880 6.8.6 */
548 if (mlen
< BFD_PKT_LEN
) {
549 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
550 "too small (%ld bytes)", mlen
);
554 /* Validate packet TTL. */
555 if ((!is_mhop
) && (ttl
!= BFD_TTL_VAL
)) {
556 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
557 "invalid TTL: %d expected %d", ttl
, BFD_TTL_VAL
);
562 * Parse the control header for inconsistencies:
564 * - Bad multiplier configuration;
566 * - Invalid discriminator;
568 cp
= (struct bfd_pkt
*)(msgbuf
);
569 if (BFD_GETVER(cp
->diag
) != BFD_VERSION
) {
570 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
571 "bad version %d", BFD_GETVER(cp
->diag
));
575 if (cp
->detect_mult
== 0) {
576 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
577 "detect multiplier set to zero");
581 if ((cp
->len
< BFD_PKT_LEN
) || (cp
->len
> mlen
)) {
582 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
, "too small");
586 if (cp
->discrs
.my_discr
== 0) {
587 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
588 "'my discriminator' is zero");
592 /* Find the session that this packet belongs. */
593 bfd
= ptm_bfd_sess_find(cp
, &peer
, &local
, ifindex
, vrfid
, is_mhop
);
595 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
600 bfd
->stats
.rx_ctrl_pkt
++;
603 * Multi hop: validate packet TTL.
604 * Single hop: set local address that received the packet.
607 if ((BFD_TTL_VAL
- bfd
->mh_ttl
) > BFD_TTL_VAL
) {
608 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
609 "exceeded max hop count (expected %d, got %d)",
610 bfd
->mh_ttl
, BFD_TTL_VAL
);
613 } else if (bfd
->local_address
.sa_sin
.sin_family
== AF_UNSPEC
) {
614 bfd
->local_address
= local
;
618 * If no interface was detected, save the interface where the
621 if (bfd
->ifp
== NULL
)
622 bfd
->ifp
= if_lookup_by_index(ifindex
, vrfid
);
624 /* Log remote discriminator changes. */
625 if ((bfd
->discrs
.remote_discr
!= 0)
626 && (bfd
->discrs
.remote_discr
!= ntohl(cp
->discrs
.my_discr
)))
627 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
628 "remote discriminator mismatch (expected %u, got %u)",
629 bfd
->discrs
.remote_discr
, ntohl(cp
->discrs
.my_discr
));
631 bfd
->discrs
.remote_discr
= ntohl(cp
->discrs
.my_discr
);
633 /* Save remote diagnostics before state switch. */
634 bfd
->remote_diag
= cp
->diag
& BFD_DIAGMASK
;
636 /* Update remote timers settings. */
637 bfd
->remote_timers
.desired_min_tx
= ntohl(cp
->timers
.desired_min_tx
);
638 bfd
->remote_timers
.required_min_rx
= ntohl(cp
->timers
.required_min_rx
);
639 bfd
->remote_timers
.required_min_echo
=
640 ntohl(cp
->timers
.required_min_echo
);
641 bfd
->remote_detect_mult
= cp
->detect_mult
;
643 /* State switch from section 6.2. */
644 bs_state_handler(bfd
, BFD_GETSTATE(cp
->flags
));
646 /* RFC 5880, Section 6.5: handle POLL/FINAL negotiation sequence. */
647 if (bfd
->polling
&& BFD_GETFBIT(cp
->flags
)) {
648 /* Disable pooling. */
651 /* Handle poll finalization. */
652 bs_final_handler(bfd
);
654 /* Received a packet, lets update the receive timer. */
655 bfd_recvtimer_update(bfd
);
658 /* Handle echo timers changes. */
659 bs_echo_timer_handler(bfd
);
662 * We've received a packet with the POLL bit set, we must send
663 * a control packet back with the FINAL bit set.
665 * RFC 5880, Section 6.5.
667 if (BFD_GETPBIT(cp
->flags
)) {
668 /* We are finalizing a poll negotiation. */
669 bs_final_handler(bfd
);
671 /* Send the control packet with the final bit immediately. */
679 * bp_bfd_echo_in: proccesses an BFD echo packet. On TTL == BFD_TTL_VAL
680 * the packet is looped back or returns the my discriminator ID along
683 * Returns -1 on error or loopback or 0 on success.
685 int bp_bfd_echo_in(int sd
, uint8_t *ttl
, uint32_t *my_discr
)
687 struct bfd_echo_pkt
*bep
;
689 struct sockaddr_any local
, peer
;
690 ifindex_t ifindex
= IFINDEX_INTERNAL
;
691 vrf_id_t vrfid
= VRF_DEFAULT
;
692 uint8_t msgbuf
[1516];
694 if (sd
== bglobal
.bg_echo
)
695 rlen
= bfd_recv_ipv4(sd
, msgbuf
, sizeof(msgbuf
), ttl
, &ifindex
,
698 rlen
= bfd_recv_ipv6(sd
, msgbuf
, sizeof(msgbuf
), ttl
, &ifindex
,
701 /* Short packet, better not risk reading it. */
702 if (rlen
< (ssize_t
)sizeof(*bep
)) {
703 cp_debug(false, &peer
, &local
, ifindex
, vrfid
,
704 "small echo packet");
708 /* Test for loopback. */
709 if (*ttl
== BFD_TTL_VAL
) {
710 bp_udp_send(sd
, *ttl
- 1, msgbuf
, rlen
,
711 (struct sockaddr
*)&peer
,
712 (sd
== bglobal
.bg_echo
) ? sizeof(peer
.sa_sin
)
713 : sizeof(peer
.sa_sin6
));
717 /* Read my discriminator from BFD Echo packet. */
718 bep
= (struct bfd_echo_pkt
*)msgbuf
;
719 *my_discr
= ntohl(bep
->my_discr
);
720 if (*my_discr
== 0) {
721 cp_debug(false, &peer
, &local
, ifindex
, vrfid
,
722 "invalid echo packet discriminator (zero)");
729 int bp_udp_send(int sd
, uint8_t ttl
, uint8_t *data
, size_t datalen
,
730 struct sockaddr
*to
, socklen_t tolen
)
732 struct cmsghdr
*cmsg
;
735 bool is_ipv6
= to
->sa_family
== AF_INET6
;
740 /* Prepare message data. */
741 iov
[0].iov_base
= data
;
742 iov
[0].iov_len
= datalen
;
744 memset(&msg
, 0, sizeof(msg
));
745 memset(msgctl
, 0, sizeof(msgctl
));
747 msg
.msg_namelen
= tolen
;
751 /* Prepare the packet TTL information. */
753 /* Use ancillary data. */
754 msg
.msg_control
= msgctl
;
755 msg
.msg_controllen
= CMSG_LEN(sizeof(ttlval
));
757 /* Configure the ancillary data. */
758 cmsg
= CMSG_FIRSTHDR(&msg
);
759 cmsg
->cmsg_len
= CMSG_LEN(sizeof(ttlval
));
761 cmsg
->cmsg_level
= IPPROTO_IPV6
;
762 cmsg
->cmsg_type
= IPV6_HOPLIMIT
;
765 cmsg
->cmsg_level
= IPPROTO_IP
;
766 cmsg
->cmsg_type
= IP_TTL
;
768 /* FreeBSD does not support TTL in ancillary data. */
769 msg
.msg_control
= NULL
;
770 msg
.msg_controllen
= 0;
775 memcpy(CMSG_DATA(cmsg
), &ttlval
, sizeof(ttlval
));
778 /* Send echo back. */
779 wlen
= sendmsg(sd
, &msg
, 0);
781 log_debug("udp-send: loopback failure: (%d) %s", errno
, strerror(errno
));
783 } else if (wlen
< (ssize_t
)datalen
) {
784 log_debug("udp-send: partial send: %ld expected %ld", wlen
,
801 int bp_set_ttl(int sd
, uint8_t value
)
805 if (setsockopt(sd
, IPPROTO_IP
, IP_TTL
, &ttl
, sizeof(ttl
)) == -1) {
806 log_warning("set-ttl: setsockopt(IP_TTL, %d): %s", value
,
814 int bp_set_tos(int sd
, uint8_t value
)
818 if (setsockopt(sd
, IPPROTO_IP
, IP_TOS
, &tos
, sizeof(tos
)) == -1) {
819 log_warning("set-tos: setsockopt(IP_TOS, %d): %s", value
,
827 static void bp_set_ipopts(int sd
)
829 int rcvttl
= BFD_RCV_TTL_VAL
;
831 if (bp_set_ttl(sd
, BFD_TTL_VAL
) != 0)
832 log_fatal("set-ipopts: TTL configuration failed");
834 if (setsockopt(sd
, IPPROTO_IP
, IP_RECVTTL
, &rcvttl
, sizeof(rcvttl
))
836 log_fatal("set-ipopts: setsockopt(IP_RECVTTL, %d): %s", rcvttl
,
840 int pktinfo
= BFD_PKT_INFO_VAL
;
842 /* Figure out address and interface to do the peer matching. */
843 if (setsockopt(sd
, IPPROTO_IP
, IP_PKTINFO
, &pktinfo
, sizeof(pktinfo
))
845 log_fatal("set-ipopts: setsockopt(IP_PKTINFO, %d): %s", pktinfo
,
847 #endif /* BFD_LINUX */
851 /* Find out our address for peer matching. */
852 if (setsockopt(sd
, IPPROTO_IP
, IP_RECVDSTADDR
, &yes
, sizeof(yes
)) == -1)
853 log_fatal("set-ipopts: setsockopt(IP_RECVDSTADDR, %d): %s", yes
,
856 /* Find out interface where the packet came in. */
857 if (setsockopt_ifindex(AF_INET
, sd
, yes
) == -1)
858 log_fatal("set-ipopts: setsockopt_ipv4_ifindex(%d): %s", yes
,
863 static void bp_bind_ip(int sd
, uint16_t port
)
865 struct sockaddr_in sin
;
867 memset(&sin
, 0, sizeof(sin
));
868 sin
.sin_family
= AF_INET
;
869 sin
.sin_addr
.s_addr
= htonl(INADDR_ANY
);
870 sin
.sin_port
= htons(port
);
871 if (bind(sd
, (struct sockaddr
*)&sin
, sizeof(sin
)) == -1)
872 log_fatal("bind-ip: bind: %s", strerror(errno
));
875 int bp_udp_shop(void)
879 sd
= socket(AF_INET
, SOCK_DGRAM
, PF_UNSPEC
);
881 log_fatal("udp-shop: socket: %s", strerror(errno
));
884 bp_bind_ip(sd
, BFD_DEFDESTPORT
);
889 int bp_udp_mhop(void)
893 sd
= socket(AF_INET
, SOCK_DGRAM
, PF_UNSPEC
);
895 log_fatal("udp-mhop: socket: %s", strerror(errno
));
898 bp_bind_ip(sd
, BFD_DEF_MHOP_DEST_PORT
);
903 int bp_peer_socket(const struct bfd_session
*bs
)
906 struct sockaddr_in sin
;
907 static int srcPort
= BFD_SRCPORTINIT
;
909 sd
= socket(AF_INET
, SOCK_DGRAM
, PF_UNSPEC
);
911 log_error("ipv4-new: failed to create socket: %s",
916 /* Set TTL to 255 for all transmitted packets */
917 if (bp_set_ttl(sd
, BFD_TTL_VAL
) != 0) {
922 /* Set TOS to CS6 for all transmitted packets */
923 if (bp_set_tos(sd
, BFD_TOS_VAL
) != 0) {
928 if (bs
->key
.ifname
[0]) {
929 if (bp_bind_dev(sd
, bs
->key
.ifname
) != 0) {
933 } else if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
)
934 && bs
->key
.vrfname
[0]) {
935 if (bp_bind_dev(sd
, bs
->key
.vrfname
) != 0) {
941 /* Find an available source port in the proper range */
942 memset(&sin
, 0, sizeof(sin
));
943 sin
.sin_family
= AF_INET
;
944 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
945 sin
.sin_len
= sizeof(sin
);
946 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
947 memcpy(&sin
.sin_addr
, &bs
->key
.local
, sizeof(sin
.sin_addr
));
948 if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
) == 0)
949 sin
.sin_addr
.s_addr
= INADDR_ANY
;
953 if ((++pcount
) > (BFD_SRCPORTMAX
- BFD_SRCPORTINIT
)) {
954 /* Searched all ports, none available */
955 log_error("ipv4-new: failed to bind port: %s",
960 if (srcPort
>= BFD_SRCPORTMAX
)
961 srcPort
= BFD_SRCPORTINIT
;
962 sin
.sin_port
= htons(srcPort
++);
963 } while (bind(sd
, (struct sockaddr
*)&sin
, sizeof(sin
)) < 0);
973 int bp_peer_socketv6(const struct bfd_session
*bs
)
976 struct sockaddr_in6 sin6
;
977 static int srcPort
= BFD_SRCPORTINIT
;
979 sd
= socket(AF_INET6
, SOCK_DGRAM
, PF_UNSPEC
);
981 log_error("ipv6-new: failed to create socket: %s",
986 /* Set TTL to 255 for all transmitted packets */
987 if (bp_set_ttlv6(sd
, BFD_TTL_VAL
) != 0) {
992 /* Set TOS to CS6 for all transmitted packets */
993 if (bp_set_tosv6(sd
, BFD_TOS_VAL
) != 0) {
998 /* Find an available source port in the proper range */
999 memset(&sin6
, 0, sizeof(sin6
));
1000 sin6
.sin6_family
= AF_INET6
;
1001 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
1002 sin6
.sin6_len
= sizeof(sin6
);
1003 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
1004 memcpy(&sin6
.sin6_addr
, &bs
->key
.local
, sizeof(sin6
.sin6_addr
));
1005 if (IN6_IS_ADDR_LINKLOCAL(&sin6
.sin6_addr
))
1006 sin6
.sin6_scope_id
= bs
->ifp
->ifindex
;
1008 if (bs
->key
.ifname
[0]) {
1009 if (bp_bind_dev(sd
, bs
->key
.ifname
) != 0) {
1013 } else if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
)
1014 && bs
->key
.vrfname
[0]) {
1015 if (bp_bind_dev(sd
, bs
->key
.vrfname
) != 0) {
1023 if ((++pcount
) > (BFD_SRCPORTMAX
- BFD_SRCPORTINIT
)) {
1024 /* Searched all ports, none available */
1025 log_error("ipv6-new: failed to bind port: %s",
1030 if (srcPort
>= BFD_SRCPORTMAX
)
1031 srcPort
= BFD_SRCPORTINIT
;
1032 sin6
.sin6_port
= htons(srcPort
++);
1033 } while (bind(sd
, (struct sockaddr
*)&sin6
, sizeof(sin6
)) < 0);
1038 int bp_set_ttlv6(int sd
, uint8_t value
)
1042 if (setsockopt(sd
, IPPROTO_IPV6
, IPV6_UNICAST_HOPS
, &ttl
, sizeof(ttl
))
1044 log_warning("set-ttlv6: setsockopt(IPV6_UNICAST_HOPS, %d): %s",
1045 value
, strerror(errno
));
1052 int bp_set_tosv6(int sd
, uint8_t value
)
1056 if (setsockopt(sd
, IPPROTO_IPV6
, IPV6_TCLASS
, &tos
, sizeof(tos
))
1058 log_warning("set-tosv6: setsockopt(IPV6_TCLASS, %d): %s", value
,
1066 static void bp_set_ipv6opts(int sd
)
1068 int ipv6_pktinfo
= BFD_IPV6_PKT_INFO_VAL
;
1069 int ipv6_only
= BFD_IPV6_ONLY_VAL
;
1071 if (bp_set_ttlv6(sd
, BFD_TTL_VAL
) == -1)
1072 log_fatal("set-ipv6opts: setsockopt(IPV6_UNICAST_HOPS, %d): %s",
1073 BFD_TTL_VAL
, strerror(errno
));
1075 if (setsockopt_ipv6_hoplimit(sd
, BFD_RCV_TTL_VAL
) == -1)
1076 log_fatal("set-ipv6opts: setsockopt(IPV6_HOPLIMIT, %d): %s",
1077 BFD_RCV_TTL_VAL
, strerror(errno
));
1079 if (setsockopt_ipv6_pktinfo(sd
, ipv6_pktinfo
) == -1)
1080 log_fatal("set-ipv6opts: setsockopt(IPV6_PKTINFO, %d): %s",
1081 ipv6_pktinfo
, strerror(errno
));
1083 if (setsockopt(sd
, IPPROTO_IPV6
, IPV6_V6ONLY
, &ipv6_only
,
1086 log_fatal("set-ipv6opts: setsockopt(IPV6_V6ONLY, %d): %s",
1087 ipv6_only
, strerror(errno
));
1090 static void bp_bind_ipv6(int sd
, uint16_t port
)
1092 struct sockaddr_in6 sin6
;
1094 memset(&sin6
, 0, sizeof(sin6
));
1095 sin6
.sin6_family
= AF_INET6
;
1096 sin6
.sin6_addr
= in6addr_any
;
1097 sin6
.sin6_port
= htons(port
);
1098 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
1099 sin6
.sin6_len
= sizeof(sin6
);
1100 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
1101 if (bind(sd
, (struct sockaddr
*)&sin6
, sizeof(sin6
)) == -1)
1102 log_fatal("bind-ipv6: bind: %s", strerror(errno
));
1105 int bp_udp6_shop(void)
1109 sd
= socket(AF_INET6
, SOCK_DGRAM
, PF_UNSPEC
);
1111 log_fatal("udp6-shop: socket: %s", strerror(errno
));
1113 bp_set_ipv6opts(sd
);
1114 bp_bind_ipv6(sd
, BFD_DEFDESTPORT
);
1119 int bp_udp6_mhop(void)
1123 sd
= socket(AF_INET6
, SOCK_DGRAM
, PF_UNSPEC
);
1125 log_fatal("udp6-mhop: socket: %s", strerror(errno
));
1127 bp_set_ipv6opts(sd
);
1128 bp_bind_ipv6(sd
, BFD_DEF_MHOP_DEST_PORT
);
1133 int bp_echo_socket(void)
1137 s
= socket(AF_INET
, SOCK_DGRAM
, 0);
1139 log_fatal("echo-socket: socket: %s", strerror(errno
));
1142 bp_bind_ip(s
, BFD_DEF_ECHO_PORT
);
1147 int bp_echov6_socket(void)
1151 s
= socket(AF_INET6
, SOCK_DGRAM
, 0);
1153 log_fatal("echov6-socket: socket: %s", strerror(errno
));
1156 bp_bind_ipv6(s
, BFD_DEF_ECHO_PORT
);