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"
43 static int ptm_bfd_process_echo_pkt(struct bfd_vrf_global
*bvrf
, int s
);
44 int _ptm_bfd_send(struct bfd_session
*bs
, uint16_t *port
, const void *data
,
47 static void bfd_sd_reschedule(struct bfd_vrf_global
*bvrf
, int sd
);
48 ssize_t
bfd_recv_ipv4(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
49 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
50 struct sockaddr_any
*peer
);
51 ssize_t
bfd_recv_ipv6(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
52 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
53 struct sockaddr_any
*peer
);
54 int bp_udp_send(int sd
, uint8_t ttl
, uint8_t *data
, size_t datalen
,
55 struct sockaddr
*to
, socklen_t tolen
);
56 int bp_bfd_echo_in(struct bfd_vrf_global
*bvrf
, int sd
,
57 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
;
132 struct bfd_vrf_global
*bvrf
= bfd_vrf_look_by_session(bfd
);
136 if (!BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_ECHO_ACTIVE
))
137 BFD_SET_FLAG(bfd
->flags
, BFD_SESS_FLAG_ECHO_ACTIVE
);
139 memset(&bep
, 0, sizeof(bep
));
140 bep
.ver
= BFD_ECHO_VERSION
;
141 bep
.len
= BFD_ECHO_PKT_LEN
;
142 bep
.my_discr
= htonl(bfd
->discrs
.my_discr
);
144 if (BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_IPV6
)) {
145 sd
= bvrf
->bg_echov6
;
146 memset(&sin6
, 0, sizeof(sin6
));
147 sin6
.sin6_family
= AF_INET6
;
148 memcpy(&sin6
.sin6_addr
, &bfd
->key
.peer
, sizeof(sin6
.sin6_addr
));
149 if (bfd
->ifp
&& IN6_IS_ADDR_LINKLOCAL(&sin6
.sin6_addr
))
150 sin6
.sin6_scope_id
= bfd
->ifp
->ifindex
;
152 sin6
.sin6_port
= htons(BFD_DEF_ECHO_PORT
);
153 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
154 sin6
.sin6_len
= sizeof(sin6
);
155 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
157 sa
= (struct sockaddr
*)&sin6
;
158 salen
= sizeof(sin6
);
161 memset(&sin6
, 0, sizeof(sin6
));
162 sin
.sin_family
= AF_INET
;
163 memcpy(&sin
.sin_addr
, &bfd
->key
.peer
, sizeof(sin
.sin_addr
));
164 sin
.sin_port
= htons(BFD_DEF_ECHO_PORT
);
165 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
166 sin
.sin_len
= sizeof(sin
);
167 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
169 sa
= (struct sockaddr
*)&sin
;
172 if (bp_udp_send(sd
, BFD_TTL_VAL
, (uint8_t *)&bep
, sizeof(bep
), sa
,
177 bfd
->stats
.tx_echo_pkt
++;
180 static int ptm_bfd_process_echo_pkt(struct bfd_vrf_global
*bvrf
, int s
)
182 struct bfd_session
*bfd
;
183 uint32_t my_discr
= 0;
186 /* Receive and parse echo packet. */
187 if (bp_bfd_echo_in(bvrf
, s
, &ttl
, &my_discr
) == -1)
190 /* Your discriminator not zero - use it to find session */
191 bfd
= bfd_id_lookup(my_discr
);
193 log_debug("echo-packet: no matching session (id:%u)", my_discr
);
197 if (!BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_ECHO_ACTIVE
)) {
198 log_debug("echo-packet: echo disabled [%s] (id:%u)",
199 bs_to_string(bfd
), my_discr
);
203 bfd
->stats
.rx_echo_pkt
++;
205 /* Compute detect time */
206 bfd
->echo_detect_TO
= bfd
->remote_detect_mult
* bfd
->echo_xmt_TO
;
208 /* Update echo receive timeout. */
209 if (bfd
->echo_detect_TO
> 0)
210 bfd_echo_recvtimer_update(bfd
);
215 void ptm_bfd_snd(struct bfd_session
*bfd
, int fbit
)
219 /* Set fields according to section 6.5.7 */
220 cp
.diag
= bfd
->local_diag
;
221 BFD_SETVER(cp
.diag
, BFD_VERSION
);
223 BFD_SETSTATE(cp
.flags
, bfd
->ses_state
);
225 if (BFD_CHECK_FLAG(bfd
->flags
, BFD_SESS_FLAG_CBIT
))
226 BFD_SETCBIT(cp
.flags
, BFD_CBIT
);
228 BFD_SETDEMANDBIT(cp
.flags
, BFD_DEF_DEMAND
);
231 * Polling and Final can't be set at the same time.
233 * RFC 5880, Section 6.5.
235 BFD_SETFBIT(cp
.flags
, fbit
);
237 BFD_SETPBIT(cp
.flags
, bfd
->polling
);
239 cp
.detect_mult
= bfd
->detect_mult
;
240 cp
.len
= BFD_PKT_LEN
;
241 cp
.discrs
.my_discr
= htonl(bfd
->discrs
.my_discr
);
242 cp
.discrs
.remote_discr
= htonl(bfd
->discrs
.remote_discr
);
244 cp
.timers
.desired_min_tx
=
245 htonl(bfd
->timers
.desired_min_tx
);
246 cp
.timers
.required_min_rx
=
247 htonl(bfd
->timers
.required_min_rx
);
250 * We can only announce current setting on poll, this
251 * avoids timing mismatch with our peer and give it
252 * the oportunity to learn. See `bs_final_handler` for
255 cp
.timers
.desired_min_tx
=
256 htonl(bfd
->cur_timers
.desired_min_tx
);
257 cp
.timers
.required_min_rx
=
258 htonl(bfd
->cur_timers
.required_min_rx
);
260 cp
.timers
.required_min_echo
= htonl(bfd
->timers
.required_min_echo
);
262 if (_ptm_bfd_send(bfd
, NULL
, &cp
, BFD_PKT_LEN
) != 0)
265 bfd
->stats
.tx_ctrl_pkt
++;
268 ssize_t
bfd_recv_ipv4(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
269 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
270 struct sockaddr_any
*peer
)
274 struct sockaddr_in msgaddr
;
275 struct msghdr msghdr
;
277 uint8_t cmsgbuf
[255];
279 /* Prepare the recvmsg params. */
280 iov
[0].iov_base
= msgbuf
;
281 iov
[0].iov_len
= msgbuflen
;
283 memset(&msghdr
, 0, sizeof(msghdr
));
284 msghdr
.msg_name
= &msgaddr
;
285 msghdr
.msg_namelen
= sizeof(msgaddr
);
286 msghdr
.msg_iov
= iov
;
287 msghdr
.msg_iovlen
= 1;
288 msghdr
.msg_control
= cmsgbuf
;
289 msghdr
.msg_controllen
= sizeof(cmsgbuf
);
291 mlen
= recvmsg(sd
, &msghdr
, MSG_DONTWAIT
);
294 log_error("ipv4-recv: recv failed: %s",
300 /* Get source address */
301 peer
->sa_sin
= *((struct sockaddr_in
*)(msghdr
.msg_name
));
303 /* Get and check TTL */
304 for (cm
= CMSG_FIRSTHDR(&msghdr
); cm
!= NULL
;
305 cm
= CMSG_NXTHDR(&msghdr
, cm
)) {
306 if (cm
->cmsg_level
!= IPPROTO_IP
)
309 switch (cm
->cmsg_type
) {
314 memcpy(&ttlval
, CMSG_DATA(cm
), sizeof(ttlval
));
316 log_debug("ipv4-recv: invalid TTL: %u", ttlval
);
324 struct in_pktinfo
*pi
=
325 (struct in_pktinfo
*)CMSG_DATA(cm
);
330 local
->sa_sin
.sin_family
= AF_INET
;
331 local
->sa_sin
.sin_addr
= pi
->ipi_addr
;
332 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
333 local
->sa_sin
.sin_len
= sizeof(local
->sa_sin
);
334 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
336 *ifindex
= pi
->ipi_ifindex
;
339 #endif /* BFD_LINUX */
342 memcpy(ttl
, CMSG_DATA(cm
), sizeof(*ttl
));
346 case IP_RECVDSTADDR
: {
349 memcpy(&ia
, CMSG_DATA(cm
), sizeof(ia
));
350 local
->sa_sin
.sin_family
= AF_INET
;
351 local
->sa_sin
.sin_addr
= ia
;
352 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
353 local
->sa_sin
.sin_len
= sizeof(local
->sa_sin
);
354 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
361 * On *BSDs we expect to land here when skipping
362 * the IP_RECVIF header. It will be handled by
363 * getsockopt_ifindex() below.
370 /* OS agnostic way of getting interface name. */
371 if (*ifindex
== IFINDEX_INTERNAL
)
372 *ifindex
= getsockopt_ifindex(AF_INET
, &msghdr
);
377 ssize_t
bfd_recv_ipv6(int sd
, uint8_t *msgbuf
, size_t msgbuflen
, uint8_t *ttl
,
378 ifindex_t
*ifindex
, struct sockaddr_any
*local
,
379 struct sockaddr_any
*peer
)
382 struct in6_pktinfo
*pi6
= NULL
;
385 struct sockaddr_in6 msgaddr6
;
386 struct msghdr msghdr6
;
388 uint8_t cmsgbuf6
[255];
390 /* Prepare the recvmsg params. */
391 iov
[0].iov_base
= msgbuf
;
392 iov
[0].iov_len
= msgbuflen
;
394 memset(&msghdr6
, 0, sizeof(msghdr6
));
395 msghdr6
.msg_name
= &msgaddr6
;
396 msghdr6
.msg_namelen
= sizeof(msgaddr6
);
397 msghdr6
.msg_iov
= iov
;
398 msghdr6
.msg_iovlen
= 1;
399 msghdr6
.msg_control
= cmsgbuf6
;
400 msghdr6
.msg_controllen
= sizeof(cmsgbuf6
);
402 mlen
= recvmsg(sd
, &msghdr6
, MSG_DONTWAIT
);
405 log_error("ipv6-recv: recv failed: %s",
411 /* Get source address */
412 peer
->sa_sin6
= *((struct sockaddr_in6
*)(msghdr6
.msg_name
));
414 /* Get and check TTL */
415 for (cm
= CMSG_FIRSTHDR(&msghdr6
); cm
!= NULL
;
416 cm
= CMSG_NXTHDR(&msghdr6
, cm
)) {
417 if (cm
->cmsg_level
!= IPPROTO_IPV6
)
420 if (cm
->cmsg_type
== IPV6_HOPLIMIT
) {
421 memcpy(&ttlval
, CMSG_DATA(cm
), sizeof(ttlval
));
423 log_debug("ipv6-recv: invalid TTL: %u", ttlval
);
428 } else if (cm
->cmsg_type
== IPV6_PKTINFO
) {
429 pi6
= (struct in6_pktinfo
*)CMSG_DATA(cm
);
431 local
->sa_sin6
.sin6_family
= AF_INET6
;
432 local
->sa_sin6
.sin6_addr
= pi6
->ipi6_addr
;
433 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
434 local
->sa_sin6
.sin6_len
= sizeof(local
->sa_sin6
);
435 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
437 *ifindex
= pi6
->ipi6_ifindex
;
439 /* Set scope ID for link local addresses. */
440 if (IN6_IS_ADDR_LINKLOCAL(
441 &peer
->sa_sin6
.sin6_addr
))
442 peer
->sa_sin6
.sin6_scope_id
= *ifindex
;
443 if (IN6_IS_ADDR_LINKLOCAL(
444 &local
->sa_sin6
.sin6_addr
))
445 local
->sa_sin6
.sin6_scope_id
= *ifindex
;
453 static void bfd_sd_reschedule(struct bfd_vrf_global
*bvrf
, int sd
)
455 if (sd
== bvrf
->bg_shop
) {
456 THREAD_OFF(bvrf
->bg_ev
[0]);
457 thread_add_read(master
, bfd_recv_cb
, bvrf
, bvrf
->bg_shop
,
459 } else if (sd
== bvrf
->bg_mhop
) {
460 THREAD_OFF(bvrf
->bg_ev
[1]);
461 thread_add_read(master
, bfd_recv_cb
, bvrf
, bvrf
->bg_mhop
,
463 } else if (sd
== bvrf
->bg_shop6
) {
464 THREAD_OFF(bvrf
->bg_ev
[2]);
465 thread_add_read(master
, bfd_recv_cb
, bvrf
, bvrf
->bg_shop6
,
467 } else if (sd
== bvrf
->bg_mhop6
) {
468 THREAD_OFF(bvrf
->bg_ev
[3]);
469 thread_add_read(master
, bfd_recv_cb
, bvrf
, bvrf
->bg_mhop6
,
471 } else if (sd
== bvrf
->bg_echo
) {
472 THREAD_OFF(bvrf
->bg_ev
[4]);
473 thread_add_read(master
, bfd_recv_cb
, bvrf
, bvrf
->bg_echo
,
475 } else if (sd
== bvrf
->bg_echov6
) {
476 THREAD_OFF(bvrf
->bg_ev
[5]);
477 thread_add_read(master
, bfd_recv_cb
, bvrf
, bvrf
->bg_echov6
,
482 static void cp_debug(bool mhop
, struct sockaddr_any
*peer
,
483 struct sockaddr_any
*local
, ifindex_t ifindex
,
484 vrf_id_t vrfid
, const char *fmt
, ...)
486 char buf
[512], peerstr
[128], localstr
[128], portstr
[64], vrfstr
[64];
489 if (peer
->sa_sin
.sin_family
)
490 snprintf(peerstr
, sizeof(peerstr
), " peer:%s", satostr(peer
));
494 if (local
->sa_sin
.sin_family
)
495 snprintf(localstr
, sizeof(localstr
), " local:%s",
500 if (ifindex
!= IFINDEX_INTERNAL
)
501 snprintf(portstr
, sizeof(portstr
), " port:%u", ifindex
);
505 if (vrfid
!= VRF_DEFAULT
)
506 snprintf(vrfstr
, sizeof(vrfstr
), " vrf:%u", vrfid
);
511 vsnprintf(buf
, sizeof(buf
), fmt
, vl
);
514 log_debug("control-packet: %s [mhop:%s%s%s%s%s]", buf
,
515 mhop
? "yes" : "no", peerstr
, localstr
, portstr
, vrfstr
);
518 int bfd_recv_cb(struct thread
*t
)
520 int sd
= THREAD_FD(t
);
521 struct bfd_session
*bfd
;
527 ifindex_t ifindex
= IFINDEX_INTERNAL
;
528 struct sockaddr_any local
, peer
;
529 uint8_t msgbuf
[1516];
530 struct bfd_vrf_global
*bvrf
= THREAD_ARG(t
);
532 vrfid
= bvrf
->vrf
->vrf_id
;
534 /* Schedule next read. */
535 bfd_sd_reschedule(bvrf
, sd
);
537 /* Handle echo packets. */
538 if (sd
== bvrf
->bg_echo
|| sd
== bvrf
->bg_echov6
) {
539 ptm_bfd_process_echo_pkt(bvrf
, sd
);
543 /* Sanitize input/output. */
544 memset(&local
, 0, sizeof(local
));
545 memset(&peer
, 0, sizeof(peer
));
547 /* Handle control packets. */
549 if (sd
== bvrf
->bg_shop
|| sd
== bvrf
->bg_mhop
) {
550 is_mhop
= sd
== bvrf
->bg_mhop
;
551 mlen
= bfd_recv_ipv4(sd
, msgbuf
, sizeof(msgbuf
), &ttl
, &ifindex
,
553 } else if (sd
== bvrf
->bg_shop6
|| sd
== bvrf
->bg_mhop6
) {
554 is_mhop
= sd
== bvrf
->bg_mhop6
;
555 mlen
= bfd_recv_ipv6(sd
, msgbuf
, sizeof(msgbuf
), &ttl
, &ifindex
,
559 /* Implement RFC 5880 6.8.6 */
560 if (mlen
< BFD_PKT_LEN
) {
561 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
562 "too small (%ld bytes)", mlen
);
566 /* Validate packet TTL. */
567 if ((!is_mhop
) && (ttl
!= BFD_TTL_VAL
)) {
568 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
569 "invalid TTL: %d expected %d", ttl
, BFD_TTL_VAL
);
574 * Parse the control header for inconsistencies:
576 * - Bad multiplier configuration;
578 * - Invalid discriminator;
580 cp
= (struct bfd_pkt
*)(msgbuf
);
581 if (BFD_GETVER(cp
->diag
) != BFD_VERSION
) {
582 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
583 "bad version %d", BFD_GETVER(cp
->diag
));
587 if (cp
->detect_mult
== 0) {
588 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
589 "detect multiplier set to zero");
593 if ((cp
->len
< BFD_PKT_LEN
) || (cp
->len
> mlen
)) {
594 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
, "too small");
598 if (cp
->discrs
.my_discr
== 0) {
599 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
600 "'my discriminator' is zero");
604 /* Find the session that this packet belongs. */
605 bfd
= ptm_bfd_sess_find(cp
, &peer
, &local
, ifindex
, vrfid
, is_mhop
);
607 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
612 bfd
->stats
.rx_ctrl_pkt
++;
615 * Multi hop: validate packet TTL.
616 * Single hop: set local address that received the packet.
619 if ((BFD_TTL_VAL
- bfd
->mh_ttl
) > BFD_TTL_VAL
) {
620 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
621 "exceeded max hop count (expected %d, got %d)",
622 bfd
->mh_ttl
, BFD_TTL_VAL
);
625 } else if (bfd
->local_address
.sa_sin
.sin_family
== AF_UNSPEC
) {
626 bfd
->local_address
= local
;
630 * If no interface was detected, save the interface where the
633 if (bfd
->ifp
== NULL
)
634 bfd
->ifp
= if_lookup_by_index(ifindex
, vrfid
);
636 /* Log remote discriminator changes. */
637 if ((bfd
->discrs
.remote_discr
!= 0)
638 && (bfd
->discrs
.remote_discr
!= ntohl(cp
->discrs
.my_discr
)))
639 cp_debug(is_mhop
, &peer
, &local
, ifindex
, vrfid
,
640 "remote discriminator mismatch (expected %u, got %u)",
641 bfd
->discrs
.remote_discr
, ntohl(cp
->discrs
.my_discr
));
643 bfd
->discrs
.remote_discr
= ntohl(cp
->discrs
.my_discr
);
645 /* Save remote diagnostics before state switch. */
646 bfd
->remote_diag
= cp
->diag
& BFD_DIAGMASK
;
648 /* Update remote timers settings. */
649 bfd
->remote_timers
.desired_min_tx
= ntohl(cp
->timers
.desired_min_tx
);
650 bfd
->remote_timers
.required_min_rx
= ntohl(cp
->timers
.required_min_rx
);
651 bfd
->remote_timers
.required_min_echo
=
652 ntohl(cp
->timers
.required_min_echo
);
653 bfd
->remote_detect_mult
= cp
->detect_mult
;
655 if (BFD_GETCBIT(cp
->flags
))
656 bfd
->remote_cbit
= 1;
658 bfd
->remote_cbit
= 0;
660 /* State switch from section 6.2. */
661 bs_state_handler(bfd
, BFD_GETSTATE(cp
->flags
));
663 /* RFC 5880, Section 6.5: handle POLL/FINAL negotiation sequence. */
664 if (bfd
->polling
&& BFD_GETFBIT(cp
->flags
)) {
665 /* Disable pooling. */
668 /* Handle poll finalization. */
669 bs_final_handler(bfd
);
671 /* Received a packet, lets update the receive timer. */
672 bfd_recvtimer_update(bfd
);
675 /* Handle echo timers changes. */
676 bs_echo_timer_handler(bfd
);
679 * We've received a packet with the POLL bit set, we must send
680 * a control packet back with the FINAL bit set.
682 * RFC 5880, Section 6.5.
684 if (BFD_GETPBIT(cp
->flags
)) {
685 /* We are finalizing a poll negotiation. */
686 bs_final_handler(bfd
);
688 /* Send the control packet with the final bit immediately. */
696 * bp_bfd_echo_in: proccesses an BFD echo packet. On TTL == BFD_TTL_VAL
697 * the packet is looped back or returns the my discriminator ID along
700 * Returns -1 on error or loopback or 0 on success.
702 int bp_bfd_echo_in(struct bfd_vrf_global
*bvrf
, int sd
,
703 uint8_t *ttl
, uint32_t *my_discr
)
705 struct bfd_echo_pkt
*bep
;
707 struct sockaddr_any local
, peer
;
708 ifindex_t ifindex
= IFINDEX_INTERNAL
;
709 vrf_id_t vrfid
= VRF_DEFAULT
;
710 uint8_t msgbuf
[1516];
712 if (sd
== bvrf
->bg_echo
)
713 rlen
= bfd_recv_ipv4(sd
, msgbuf
, sizeof(msgbuf
), ttl
, &ifindex
,
716 rlen
= bfd_recv_ipv6(sd
, msgbuf
, sizeof(msgbuf
), ttl
, &ifindex
,
719 /* Short packet, better not risk reading it. */
720 if (rlen
< (ssize_t
)sizeof(*bep
)) {
721 cp_debug(false, &peer
, &local
, ifindex
, vrfid
,
722 "small echo packet");
726 /* Test for loopback. */
727 if (*ttl
== BFD_TTL_VAL
) {
728 bp_udp_send(sd
, *ttl
- 1, msgbuf
, rlen
,
729 (struct sockaddr
*)&peer
,
730 (sd
== bvrf
->bg_echo
) ? sizeof(peer
.sa_sin
)
731 : sizeof(peer
.sa_sin6
));
735 /* Read my discriminator from BFD Echo packet. */
736 bep
= (struct bfd_echo_pkt
*)msgbuf
;
737 *my_discr
= ntohl(bep
->my_discr
);
738 if (*my_discr
== 0) {
739 cp_debug(false, &peer
, &local
, ifindex
, vrfid
,
740 "invalid echo packet discriminator (zero)");
747 int bp_udp_send(int sd
, uint8_t ttl
, uint8_t *data
, size_t datalen
,
748 struct sockaddr
*to
, socklen_t tolen
)
750 struct cmsghdr
*cmsg
;
753 bool is_ipv6
= to
->sa_family
== AF_INET6
;
758 /* Prepare message data. */
759 iov
[0].iov_base
= data
;
760 iov
[0].iov_len
= datalen
;
762 memset(&msg
, 0, sizeof(msg
));
763 memset(msgctl
, 0, sizeof(msgctl
));
765 msg
.msg_namelen
= tolen
;
769 /* Prepare the packet TTL information. */
771 /* Use ancillary data. */
772 msg
.msg_control
= msgctl
;
773 msg
.msg_controllen
= CMSG_LEN(sizeof(ttlval
));
775 /* Configure the ancillary data. */
776 cmsg
= CMSG_FIRSTHDR(&msg
);
777 cmsg
->cmsg_len
= CMSG_LEN(sizeof(ttlval
));
779 cmsg
->cmsg_level
= IPPROTO_IPV6
;
780 cmsg
->cmsg_type
= IPV6_HOPLIMIT
;
783 cmsg
->cmsg_level
= IPPROTO_IP
;
784 cmsg
->cmsg_type
= IP_TTL
;
786 /* FreeBSD does not support TTL in ancillary data. */
787 msg
.msg_control
= NULL
;
788 msg
.msg_controllen
= 0;
793 memcpy(CMSG_DATA(cmsg
), &ttlval
, sizeof(ttlval
));
796 /* Send echo back. */
797 wlen
= sendmsg(sd
, &msg
, 0);
799 log_debug("udp-send: loopback failure: (%d) %s", errno
, strerror(errno
));
801 } else if (wlen
< (ssize_t
)datalen
) {
802 log_debug("udp-send: partial send: %ld expected %ld", wlen
,
819 int bp_set_ttl(int sd
, uint8_t value
)
823 if (setsockopt(sd
, IPPROTO_IP
, IP_TTL
, &ttl
, sizeof(ttl
)) == -1) {
824 log_warning("set-ttl: setsockopt(IP_TTL, %d): %s", value
,
832 int bp_set_tos(int sd
, uint8_t value
)
836 if (setsockopt(sd
, IPPROTO_IP
, IP_TOS
, &tos
, sizeof(tos
)) == -1) {
837 log_warning("set-tos: setsockopt(IP_TOS, %d): %s", value
,
845 static void bp_set_ipopts(int sd
)
847 int rcvttl
= BFD_RCV_TTL_VAL
;
849 if (bp_set_ttl(sd
, BFD_TTL_VAL
) != 0)
850 log_fatal("set-ipopts: TTL configuration failed");
852 if (setsockopt(sd
, IPPROTO_IP
, IP_RECVTTL
, &rcvttl
, sizeof(rcvttl
))
854 log_fatal("set-ipopts: setsockopt(IP_RECVTTL, %d): %s", rcvttl
,
858 int pktinfo
= BFD_PKT_INFO_VAL
;
860 /* Figure out address and interface to do the peer matching. */
861 if (setsockopt(sd
, IPPROTO_IP
, IP_PKTINFO
, &pktinfo
, sizeof(pktinfo
))
863 log_fatal("set-ipopts: setsockopt(IP_PKTINFO, %d): %s", pktinfo
,
865 #endif /* BFD_LINUX */
869 /* Find out our address for peer matching. */
870 if (setsockopt(sd
, IPPROTO_IP
, IP_RECVDSTADDR
, &yes
, sizeof(yes
)) == -1)
871 log_fatal("set-ipopts: setsockopt(IP_RECVDSTADDR, %d): %s", yes
,
874 /* Find out interface where the packet came in. */
875 if (setsockopt_ifindex(AF_INET
, sd
, yes
) == -1)
876 log_fatal("set-ipopts: setsockopt_ipv4_ifindex(%d): %s", yes
,
881 static void bp_bind_ip(int sd
, uint16_t port
)
883 struct sockaddr_in sin
;
885 memset(&sin
, 0, sizeof(sin
));
886 sin
.sin_family
= AF_INET
;
887 sin
.sin_addr
.s_addr
= htonl(INADDR_ANY
);
888 sin
.sin_port
= htons(port
);
889 if (bind(sd
, (struct sockaddr
*)&sin
, sizeof(sin
)) == -1)
890 log_fatal("bind-ip: bind: %s", strerror(errno
));
893 int bp_udp_shop(const struct vrf
*vrf
)
897 frr_with_privs(&bglobal
.bfdd_privs
) {
898 sd
= vrf_socket(AF_INET
, SOCK_DGRAM
, PF_UNSPEC
, vrf
->vrf_id
,
902 log_fatal("udp-shop: socket: %s", strerror(errno
));
905 bp_bind_ip(sd
, BFD_DEFDESTPORT
);
909 int bp_udp_mhop(const struct vrf
*vrf
)
913 frr_with_privs(&bglobal
.bfdd_privs
) {
914 sd
= vrf_socket(AF_INET
, SOCK_DGRAM
, PF_UNSPEC
, vrf
->vrf_id
,
918 log_fatal("udp-mhop: socket: %s", strerror(errno
));
921 bp_bind_ip(sd
, BFD_DEF_MHOP_DEST_PORT
);
926 int bp_peer_socket(const struct bfd_session
*bs
)
929 struct sockaddr_in sin
;
930 static int srcPort
= BFD_SRCPORTINIT
;
931 const char *device_to_bind
= NULL
;
933 if (bs
->key
.ifname
[0])
934 device_to_bind
= (const char *)bs
->key
.ifname
;
935 else if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
)
936 && bs
->key
.vrfname
[0])
937 device_to_bind
= (const char *)bs
->key
.vrfname
;
939 frr_with_privs(&bglobal
.bfdd_privs
) {
940 sd
= vrf_socket(AF_INET
, SOCK_DGRAM
, PF_UNSPEC
,
941 bs
->vrf
->vrf_id
, device_to_bind
);
944 log_error("ipv4-new: failed to create socket: %s",
949 /* Set TTL to 255 for all transmitted packets */
950 if (bp_set_ttl(sd
, BFD_TTL_VAL
) != 0) {
955 /* Set TOS to CS6 for all transmitted packets */
956 if (bp_set_tos(sd
, BFD_TOS_VAL
) != 0) {
961 /* Find an available source port in the proper range */
962 memset(&sin
, 0, sizeof(sin
));
963 sin
.sin_family
= AF_INET
;
964 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
965 sin
.sin_len
= sizeof(sin
);
966 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
967 memcpy(&sin
.sin_addr
, &bs
->key
.local
, sizeof(sin
.sin_addr
));
968 if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
) == 0)
969 sin
.sin_addr
.s_addr
= INADDR_ANY
;
973 if ((++pcount
) > (BFD_SRCPORTMAX
- BFD_SRCPORTINIT
)) {
974 /* Searched all ports, none available */
975 log_error("ipv4-new: failed to bind port: %s",
980 if (srcPort
>= BFD_SRCPORTMAX
)
981 srcPort
= BFD_SRCPORTINIT
;
982 sin
.sin_port
= htons(srcPort
++);
983 } while (bind(sd
, (struct sockaddr
*)&sin
, sizeof(sin
)) < 0);
993 int bp_peer_socketv6(const struct bfd_session
*bs
)
996 struct sockaddr_in6 sin6
;
997 static int srcPort
= BFD_SRCPORTINIT
;
998 const char *device_to_bind
= NULL
;
1000 if (bs
->key
.ifname
[0])
1001 device_to_bind
= (const char *)bs
->key
.ifname
;
1002 else if (BFD_CHECK_FLAG(bs
->flags
, BFD_SESS_FLAG_MH
)
1003 && bs
->key
.vrfname
[0])
1004 device_to_bind
= (const char *)bs
->key
.vrfname
;
1006 frr_with_privs(&bglobal
.bfdd_privs
) {
1007 sd
= vrf_socket(AF_INET6
, SOCK_DGRAM
, PF_UNSPEC
,
1008 bs
->vrf
->vrf_id
, device_to_bind
);
1011 log_error("ipv6-new: failed to create socket: %s",
1016 /* Set TTL to 255 for all transmitted packets */
1017 if (bp_set_ttlv6(sd
, BFD_TTL_VAL
) != 0) {
1022 /* Set TOS to CS6 for all transmitted packets */
1023 if (bp_set_tosv6(sd
, BFD_TOS_VAL
) != 0) {
1028 /* Find an available source port in the proper range */
1029 memset(&sin6
, 0, sizeof(sin6
));
1030 sin6
.sin6_family
= AF_INET6
;
1031 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
1032 sin6
.sin6_len
= sizeof(sin6
);
1033 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
1034 memcpy(&sin6
.sin6_addr
, &bs
->key
.local
, sizeof(sin6
.sin6_addr
));
1035 if (IN6_IS_ADDR_LINKLOCAL(&sin6
.sin6_addr
))
1036 sin6
.sin6_scope_id
= bs
->ifp
->ifindex
;
1040 if ((++pcount
) > (BFD_SRCPORTMAX
- BFD_SRCPORTINIT
)) {
1041 /* Searched all ports, none available */
1042 log_error("ipv6-new: failed to bind port: %s",
1047 if (srcPort
>= BFD_SRCPORTMAX
)
1048 srcPort
= BFD_SRCPORTINIT
;
1049 sin6
.sin6_port
= htons(srcPort
++);
1050 } while (bind(sd
, (struct sockaddr
*)&sin6
, sizeof(sin6
)) < 0);
1055 int bp_set_ttlv6(int sd
, uint8_t value
)
1059 if (setsockopt(sd
, IPPROTO_IPV6
, IPV6_UNICAST_HOPS
, &ttl
, sizeof(ttl
))
1061 log_warning("set-ttlv6: setsockopt(IPV6_UNICAST_HOPS, %d): %s",
1062 value
, strerror(errno
));
1069 int bp_set_tosv6(int sd
, uint8_t value
)
1073 if (setsockopt(sd
, IPPROTO_IPV6
, IPV6_TCLASS
, &tos
, sizeof(tos
))
1075 log_warning("set-tosv6: setsockopt(IPV6_TCLASS, %d): %s", value
,
1083 static void bp_set_ipv6opts(int sd
)
1085 int ipv6_pktinfo
= BFD_IPV6_PKT_INFO_VAL
;
1086 int ipv6_only
= BFD_IPV6_ONLY_VAL
;
1088 if (bp_set_ttlv6(sd
, BFD_TTL_VAL
) == -1)
1089 log_fatal("set-ipv6opts: setsockopt(IPV6_UNICAST_HOPS, %d): %s",
1090 BFD_TTL_VAL
, strerror(errno
));
1092 if (setsockopt_ipv6_hoplimit(sd
, BFD_RCV_TTL_VAL
) == -1)
1093 log_fatal("set-ipv6opts: setsockopt(IPV6_HOPLIMIT, %d): %s",
1094 BFD_RCV_TTL_VAL
, strerror(errno
));
1096 if (setsockopt_ipv6_pktinfo(sd
, ipv6_pktinfo
) == -1)
1097 log_fatal("set-ipv6opts: setsockopt(IPV6_PKTINFO, %d): %s",
1098 ipv6_pktinfo
, strerror(errno
));
1100 if (setsockopt(sd
, IPPROTO_IPV6
, IPV6_V6ONLY
, &ipv6_only
,
1103 log_fatal("set-ipv6opts: setsockopt(IPV6_V6ONLY, %d): %s",
1104 ipv6_only
, strerror(errno
));
1107 static void bp_bind_ipv6(int sd
, uint16_t port
)
1109 struct sockaddr_in6 sin6
;
1111 memset(&sin6
, 0, sizeof(sin6
));
1112 sin6
.sin6_family
= AF_INET6
;
1113 sin6
.sin6_addr
= in6addr_any
;
1114 sin6
.sin6_port
= htons(port
);
1115 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
1116 sin6
.sin6_len
= sizeof(sin6
);
1117 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
1118 if (bind(sd
, (struct sockaddr
*)&sin6
, sizeof(sin6
)) == -1)
1119 log_fatal("bind-ipv6: bind: %s", strerror(errno
));
1122 int bp_udp6_shop(const struct vrf
*vrf
)
1126 frr_with_privs(&bglobal
.bfdd_privs
) {
1127 sd
= vrf_socket(AF_INET6
, SOCK_DGRAM
, PF_UNSPEC
, vrf
->vrf_id
,
1131 log_fatal("udp6-shop: socket: %s", strerror(errno
));
1133 bp_set_ipv6opts(sd
);
1134 bp_bind_ipv6(sd
, BFD_DEFDESTPORT
);
1139 int bp_udp6_mhop(const struct vrf
*vrf
)
1143 frr_with_privs(&bglobal
.bfdd_privs
) {
1144 sd
= vrf_socket(AF_INET6
, SOCK_DGRAM
, PF_UNSPEC
, vrf
->vrf_id
,
1148 log_fatal("udp6-mhop: socket: %s", strerror(errno
));
1150 bp_set_ipv6opts(sd
);
1151 bp_bind_ipv6(sd
, BFD_DEF_MHOP_DEST_PORT
);
1156 int bp_echo_socket(const struct vrf
*vrf
)
1160 frr_with_privs(&bglobal
.bfdd_privs
) {
1161 s
= vrf_socket(AF_INET
, SOCK_DGRAM
, 0, vrf
->vrf_id
, vrf
->name
);
1164 log_fatal("echo-socket: socket: %s", strerror(errno
));
1167 bp_bind_ip(s
, BFD_DEF_ECHO_PORT
);
1172 int bp_echov6_socket(const struct vrf
*vrf
)
1176 frr_with_privs(&bglobal
.bfdd_privs
) {
1177 s
= vrf_socket(AF_INET6
, SOCK_DGRAM
, 0, vrf
->vrf_id
, vrf
->name
);
1180 log_fatal("echov6-socket: socket: %s", strerror(errno
));
1183 bp_bind_ipv6(s
, BFD_DEF_ECHO_PORT
);