]>
git.proxmox.com Git - mirror_frr.git/blob - pimd/pim_igmp_mtrace.c
2 * Multicast traceroute for FRRouting
3 * Copyright (C) 2017 Mladen Sablic
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; see the file COPYING; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
27 #include "pim_ifchannel.h"
28 #include "pim_macro.h"
29 #include "pim_igmp_mtrace.h"
31 static void mtrace_rsp_init(struct igmp_mtrace_rsp
*mtrace_rspp
)
33 mtrace_rspp
->arrival
= 0;
34 mtrace_rspp
->incoming
.s_addr
= 0;
35 mtrace_rspp
->outgoing
.s_addr
= 0;
36 mtrace_rspp
->prev_hop
.s_addr
= 0;
37 mtrace_rspp
->in_count
= MTRACE_UNKNOWN_COUNT
;
38 mtrace_rspp
->out_count
= MTRACE_UNKNOWN_COUNT
;
39 mtrace_rspp
->total
= MTRACE_UNKNOWN_COUNT
;
40 mtrace_rspp
->rtg_proto
= 0;
41 mtrace_rspp
->fwd_ttl
= 0;
44 mtrace_rspp
->src_mask
= 0;
45 mtrace_rspp
->fwd_code
= MTRACE_FWD_CODE_NO_ERROR
;
48 static void mtrace_rsp_debug(uint32_t qry_id
, int rsp
,
49 struct igmp_mtrace_rsp
*mrspp
)
51 char inc_str
[INET_ADDRSTRLEN
];
52 char out_str
[INET_ADDRSTRLEN
];
53 char prv_str
[INET_ADDRSTRLEN
];
56 "Rx mt(%d) qid=%ud arr=%x in=%s out=%s prev=%s proto=%d fwd=%d",
57 rsp
, ntohl(qry_id
), mrspp
->arrival
,
58 inet_ntop(AF_INET
, &(mrspp
->incoming
), inc_str
,
60 inet_ntop(AF_INET
, &(mrspp
->outgoing
), out_str
,
62 inet_ntop(AF_INET
, &(mrspp
->prev_hop
), prv_str
,
64 mrspp
->rtg_proto
, mrspp
->fwd_code
);
67 static void mtrace_debug(struct pim_interface
*pim_ifp
,
68 struct igmp_mtrace
*mtracep
, int mtrace_len
)
70 char inc_str
[INET_ADDRSTRLEN
];
71 char grp_str
[INET_ADDRSTRLEN
];
72 char src_str
[INET_ADDRSTRLEN
];
73 char dst_str
[INET_ADDRSTRLEN
];
74 char rsp_str
[INET_ADDRSTRLEN
];
77 "Rx mtrace packet incoming on %s: "
78 "hops=%d type=%d size=%d, grp=%s, src=%s,"
79 " dst=%s rsp=%s ttl=%d qid=%ud",
80 inet_ntop(AF_INET
, &(pim_ifp
->primary_address
), inc_str
,
82 mtracep
->hops
, mtracep
->type
, mtrace_len
,
83 inet_ntop(AF_INET
, &(mtracep
->grp_addr
), grp_str
,
85 inet_ntop(AF_INET
, &(mtracep
->src_addr
), src_str
,
87 inet_ntop(AF_INET
, &(mtracep
->dst_addr
), dst_str
,
89 inet_ntop(AF_INET
, &(mtracep
->rsp_addr
), rsp_str
,
91 mtracep
->rsp_ttl
, ntohl(mtracep
->qry_id
));
92 if (mtrace_len
> (int)sizeof(struct igmp_mtrace
)) {
96 int responses
= mtrace_len
- sizeof(struct igmp_mtrace
);
98 if ((responses
% sizeof(struct igmp_mtrace_rsp
)) != 0)
101 "Mtrace response block of wrong"
104 responses
= responses
/ sizeof(struct igmp_mtrace_rsp
);
106 for (i
= 0; i
< responses
; i
++)
107 mtrace_rsp_debug(mtracep
->qry_id
, i
, &mtracep
->rsp
[i
]);
111 /* 5.1 Query Arrival Time */
112 static uint32_t query_arrival_time(void)
117 char m_qat
[] = "Query arrival time lookup failed: errno=%d: %s";
119 if (gettimeofday(&tv
, NULL
) < 0) {
120 if (PIM_DEBUG_MTRACE
)
121 zlog_warn(m_qat
, errno
, safe_strerror(errno
));
124 /* not sure second offset correct, as I get different value */
125 qat
= ((tv
.tv_sec
+ 32384) << 16) + ((tv
.tv_usec
<< 10) / 15625);
130 static int mtrace_send_packet(struct interface
*ifp
,
131 struct igmp_mtrace
*mtracep
,
132 size_t mtrace_buf_len
, struct in_addr dst_addr
,
133 struct in_addr group_addr
)
135 struct sockaddr_in to
;
136 struct pim_interface
*pim_ifp
;
141 char pim_str
[INET_ADDRSTRLEN
];
142 char rsp_str
[INET_ADDRSTRLEN
];
147 memset(&to
, 0, sizeof(to
));
148 to
.sin_family
= AF_INET
;
149 to
.sin_addr
= dst_addr
;
152 if (PIM_DEBUG_MTRACE
)
153 zlog_debug("Sending mtrace packet to %s on %s",
154 inet_ntop(AF_INET
, &mtracep
->rsp_addr
, rsp_str
,
156 inet_ntop(AF_INET
, &pim_ifp
->primary_address
,
157 pim_str
, sizeof(pim_str
)));
159 fd
= pim_socket_raw(IPPROTO_IGMP
);
164 ret
= pim_socket_bind(fd
, ifp
);
171 if (IPV4_CLASS_DE(ntohl(dst_addr
.s_addr
))) {
172 if (IPV4_MC_LINKLOCAL(ntohl(dst_addr
.s_addr
))) {
175 if (mtracep
->type
== PIM_IGMP_MTRACE_RESPONSE
)
176 ttl
= mtracep
->rsp_ttl
;
180 ret
= setsockopt(fd
, IPPROTO_IP
, IP_MULTICAST_TTL
, &ttl
,
184 if (PIM_DEBUG_MTRACE
)
185 zlog_warn("Failed to set socket multicast TTL");
191 sent
= sendto(fd
, (char *)mtracep
, mtrace_buf_len
, MSG_DONTWAIT
,
192 (struct sockaddr
*)&to
, tolen
);
194 if (sent
!= (ssize_t
)mtrace_buf_len
) {
195 char dst_str
[INET_ADDRSTRLEN
];
196 char group_str
[INET_ADDRSTRLEN
];
198 pim_inet4_dump("<dst?>", dst_addr
, dst_str
, sizeof(dst_str
));
199 pim_inet4_dump("<group?>", group_addr
, group_str
,
202 if (PIM_DEBUG_MTRACE
)
204 "Send mtrace request failed for %s on"
205 "%s: group=%s msg_size=%zd: errno=%d: "
207 dst_str
, ifp
->name
, group_str
,
208 mtrace_buf_len
, errno
,
209 safe_strerror(errno
));
211 if (PIM_DEBUG_MTRACE
)
213 "Send mtrace request failed for %s on"
214 " %s: group=%s msg_size=%zd: sent=%zd",
215 dst_str
, ifp
->name
, group_str
,
216 mtrace_buf_len
, sent
);
227 static int mtrace_un_forward_packet(struct pim_instance
*pim
, struct ip
*ip_hdr
,
228 struct interface
*interface
)
230 struct pim_nexthop nexthop
;
231 struct sockaddr_in to
;
232 struct interface
*if_out
;
239 checksum
= ip_hdr
->ip_sum
;
243 if (checksum
!= in_cksum(ip_hdr
, ip_hdr
->ip_hl
* 4))
246 if (ip_hdr
->ip_ttl
-- <= 1)
249 ip_hdr
->ip_sum
= in_cksum(ip_hdr
, ip_hdr
->ip_hl
* 4);
251 fd
= pim_socket_raw(IPPROTO_RAW
);
256 pim_socket_ip_hdr(fd
);
258 if (interface
== NULL
) {
259 ret
= pim_nexthop_lookup(pim
, &nexthop
, ip_hdr
->ip_dst
, 0);
262 if (PIM_DEBUG_MTRACE
)
264 "Dropping mtrace packet, "
265 "no route to destination");
269 if_out
= nexthop
.interface
;
274 ret
= pim_socket_bind(fd
, if_out
);
281 memset(&to
, 0, sizeof(to
));
282 to
.sin_family
= AF_INET
;
283 to
.sin_addr
= ip_hdr
->ip_dst
;
286 sent
= sendto(fd
, ip_hdr
, ntohs(ip_hdr
->ip_len
), 0,
287 (struct sockaddr
*)&to
, tolen
);
292 if (PIM_DEBUG_MTRACE
)
294 "Failed to forward mtrace packet:"
295 " sendto errno=%d, %s",
296 errno
, safe_strerror(errno
));
300 if (PIM_DEBUG_MTRACE
) {
301 zlog_debug("Fwd mtrace packet len=%u to %s ttl=%u",
302 ntohs(ip_hdr
->ip_len
), inet_ntoa(ip_hdr
->ip_dst
),
309 static int mtrace_mc_forward_packet(struct pim_instance
*pim
, struct ip
*ip_hdr
)
312 struct channel_oil
*c_oil
;
313 struct listnode
*chnode
;
314 struct listnode
*chnextnode
;
315 struct pim_ifchannel
*ch
= NULL
;
318 memset(&sg
, 0, sizeof(struct prefix_sg
));
319 sg
.grp
= ip_hdr
->ip_dst
;
321 c_oil
= pim_find_channel_oil(pim
, &sg
);
324 if (PIM_DEBUG_MTRACE
) {
326 "Dropping mtrace multicast packet "
327 "len=%u to %s ttl=%u",
328 ntohs(ip_hdr
->ip_len
),
329 inet_ntoa(ip_hdr
->ip_dst
), ip_hdr
->ip_ttl
);
333 if (c_oil
->up
== NULL
)
335 if (c_oil
->up
->ifchannels
== NULL
)
337 for (ALL_LIST_ELEMENTS(c_oil
->up
->ifchannels
, chnode
, chnextnode
, ch
)) {
338 if (pim_macro_chisin_oiflist(ch
)) {
341 r
= mtrace_un_forward_packet(pim
, ip_hdr
,
351 static int mtrace_forward_packet(struct pim_instance
*pim
, struct ip
*ip_hdr
)
353 if (IPV4_CLASS_DE(ntohl(ip_hdr
->ip_dst
.s_addr
)))
354 return mtrace_mc_forward_packet(pim
, ip_hdr
);
356 return mtrace_un_forward_packet(pim
, ip_hdr
, NULL
);
359 /* 6.5 Sending Traceroute Responses */
360 static int mtrace_send_mc_response(struct pim_instance
*pim
,
361 struct igmp_mtrace
*mtracep
,
365 struct channel_oil
*c_oil
;
366 struct listnode
*chnode
;
367 struct listnode
*chnextnode
;
368 struct pim_ifchannel
*ch
= NULL
;
371 memset(&sg
, 0, sizeof(struct prefix_sg
));
372 sg
.grp
= mtracep
->rsp_addr
;
374 c_oil
= pim_find_channel_oil(pim
, &sg
);
377 if (PIM_DEBUG_MTRACE
) {
379 "Dropping mtrace multicast response packet "
381 (unsigned int)mtrace_len
,
382 inet_ntoa(mtracep
->rsp_addr
));
386 if (c_oil
->up
== NULL
)
388 if (c_oil
->up
->ifchannels
== NULL
)
390 for (ALL_LIST_ELEMENTS(c_oil
->up
->ifchannels
, chnode
, chnextnode
, ch
)) {
391 if (pim_macro_chisin_oiflist(ch
)) {
394 r
= mtrace_send_packet(ch
->interface
, mtracep
,
395 mtrace_len
, mtracep
->rsp_addr
,
404 static int mtrace_send_response(struct pim_instance
*pim
,
405 struct igmp_mtrace
*mtracep
, size_t mtrace_len
)
407 struct pim_nexthop nexthop
;
410 mtracep
->type
= PIM_IGMP_MTRACE_RESPONSE
;
412 mtracep
->checksum
= 0;
413 mtracep
->checksum
= in_cksum((char *)mtracep
, mtrace_len
);
415 if (IPV4_CLASS_DE(ntohl(mtracep
->rsp_addr
.s_addr
))) {
416 struct pim_rpf
*p_rpf
;
417 char grp_str
[INET_ADDRSTRLEN
];
419 if (pim_rp_i_am_rp(pim
, mtracep
->rsp_addr
))
420 return mtrace_send_mc_response(pim
, mtracep
,
423 p_rpf
= pim_rp_g(pim
, mtracep
->rsp_addr
);
426 if (PIM_DEBUG_MTRACE
)
427 zlog_warn("mtrace no RP for %s",
429 &(mtracep
->rsp_addr
),
430 grp_str
, sizeof(grp_str
)));
433 nexthop
= p_rpf
->source_nexthop
;
434 if (PIM_DEBUG_MTRACE
)
435 zlog_debug("mtrace response to RP");
437 /* TODO: should use unicast rib lookup */
438 ret
= pim_nexthop_lookup(pim
, &nexthop
, mtracep
->rsp_addr
, 1);
441 if (PIM_DEBUG_MTRACE
)
443 "Dropped response qid=%ud, no route to "
450 return mtrace_send_packet(nexthop
.interface
, mtracep
, mtrace_len
,
451 mtracep
->rsp_addr
, mtracep
->grp_addr
);
454 int igmp_mtrace_recv_qry_req(struct igmp_sock
*igmp
, struct ip
*ip_hdr
,
455 struct in_addr from
, const char *from_str
,
456 char *igmp_msg
, int igmp_msg_len
)
458 static uint32_t qry_id
, qry_src
;
459 char mtrace_buf
[MTRACE_HDR_SIZE
+ MTRACE_MAX_HOPS
* MTRACE_RSP_SIZE
];
460 struct pim_nexthop nexthop
;
461 struct interface
*ifp
;
462 struct interface
*out_ifp
;
463 struct pim_interface
*pim_ifp
;
464 struct pim_interface
*pim_out_ifp
;
465 struct pim_instance
*pim
;
466 struct igmp_mtrace
*mtracep
;
467 struct igmp_mtrace_rsp
*rspp
;
468 struct in_addr nh_addr
;
469 enum mtrace_fwd_code fwd_code
= MTRACE_FWD_CODE_NO_ERROR
;
472 int last_rsp_ind
= 0;
474 uint16_t recv_checksum
;
477 ifp
= igmp
->interface
;
482 * 6. Router Behaviour
483 * Check if mtrace packet is addressed elsewhere and forward,
486 if (!IPV4_CLASS_DE(ntohl(ip_hdr
->ip_dst
.s_addr
)))
487 if (!if_lookup_exact_address(&ip_hdr
->ip_dst
, AF_INET
,
489 return mtrace_forward_packet(pim
, ip_hdr
);
491 if (igmp_msg_len
< (int)sizeof(struct igmp_mtrace
)) {
492 if (PIM_DEBUG_MTRACE
)
494 "Recv mtrace packet from %s on %s: too short,"
496 from_str
, ifp
->name
, igmp_msg_len
,
497 sizeof(struct igmp_mtrace
));
501 mtracep
= (struct igmp_mtrace
*)igmp_msg
;
503 recv_checksum
= mtracep
->checksum
;
505 mtracep
->checksum
= 0;
507 checksum
= in_cksum(igmp_msg
, igmp_msg_len
);
509 if (recv_checksum
!= checksum
) {
510 if (PIM_DEBUG_MTRACE
)
512 "Recv mtrace packet from %s on %s: checksum"
513 " mismatch: received=%x computed=%x",
514 from_str
, ifp
->name
, recv_checksum
, checksum
);
518 if (PIM_DEBUG_MTRACE
)
519 mtrace_debug(pim_ifp
, mtracep
, igmp_msg_len
);
521 /* subtract header from message length */
522 r_len
= igmp_msg_len
- sizeof(struct igmp_mtrace
);
524 /* Classify mtrace packet, check if it is a query */
526 if (PIM_DEBUG_MTRACE
)
527 zlog_debug("Received IGMP multicast traceroute query");
529 /* 6.1.1 Packet verification */
530 if (!pim_if_connected_to_source(ifp
, mtracep
->dst_addr
)) {
531 if (IPV4_CLASS_DE(ntohl(ip_hdr
->ip_dst
.s_addr
))) {
532 if (PIM_DEBUG_MTRACE
)
534 "Dropping multicast query "
535 "on wrong interface");
538 /* Unicast query on wrong interface */
539 fwd_code
= MTRACE_FWD_CODE_WRONG_IF
;
541 if (qry_id
== mtracep
->qry_id
&& qry_src
== from
.s_addr
) {
542 if (PIM_DEBUG_MTRACE
)
544 "Dropping multicast query with "
545 "duplicate source and id");
548 qry_id
= mtracep
->qry_id
;
549 qry_src
= from
.s_addr
;
551 /* if response fields length is equal to a whole number of responses */
552 else if ((r_len
% sizeof(struct igmp_mtrace_rsp
)) == 0) {
553 r_len
= igmp_msg_len
- sizeof(struct igmp_mtrace
);
556 last_rsp_ind
= r_len
/ sizeof(struct igmp_mtrace_rsp
);
557 if (last_rsp_ind
> MTRACE_MAX_HOPS
) {
558 if (PIM_DEBUG_MTRACE
)
559 zlog_warn("Mtrace request of excessive size");
563 if (PIM_DEBUG_MTRACE
)
565 "Recv mtrace packet from %s on %s: "
567 from_str
, ifp
->name
, igmp_msg_len
);
571 /* 6.2.1 Packet Verification - drop not link-local multicast */
572 if (IPV4_CLASS_DE(ntohl(ip_hdr
->ip_dst
.s_addr
))
573 && !IPV4_MC_LINKLOCAL(ntohl(ip_hdr
->ip_dst
.s_addr
))) {
574 if (PIM_DEBUG_MTRACE
)
576 "Recv mtrace packet from %s on %s:"
577 " not link-local multicast %s",
578 from_str
, ifp
->name
, inet_ntoa(ip_hdr
->ip_dst
));
582 /* 6.2.2. Normal Processing */
586 if (last_rsp_ind
== MTRACE_MAX_HOPS
) {
587 mtracep
->rsp
[MTRACE_MAX_HOPS
- 1].fwd_code
=
588 MTRACE_FWD_CODE_NO_SPACE
;
589 return mtrace_send_response(pim_ifp
->pim
, mtracep
,
593 /* calculate new mtrace mtrace lenght with extra response */
594 mtrace_len
= igmp_msg_len
+ sizeof(struct igmp_mtrace_rsp
);
596 /* copy received query/request */
597 memcpy(mtrace_buf
, igmp_msg
, igmp_msg_len
);
599 /* repoint mtracep pointer to copy */
600 mtracep
= (struct igmp_mtrace
*)mtrace_buf
;
602 /* pointer for extra response field to be filled in */
603 rspp
= &mtracep
->rsp
[last_rsp_ind
];
605 /* initialize extra response field */
606 mtrace_rsp_init(rspp
);
608 rspp
->arrival
= htonl(query_arrival_time());
609 rspp
->outgoing
= pim_ifp
->primary_address
;
610 rspp
->out_count
= htonl(MTRACE_UNKNOWN_COUNT
);
612 /* 6.2.2. 2. Attempt to determine forwarding information */
616 ret
= pim_nexthop_lookup(pim
, &nexthop
, mtracep
->src_addr
, 1);
619 char nexthop_str
[INET_ADDRSTRLEN
];
621 if (PIM_DEBUG_MTRACE
)
622 zlog_debug("mtrace pim_nexthop_lookup OK");
624 if (PIM_DEBUG_MTRACE
)
625 zlog_warn("mtrace next_hop=%s",
626 inet_ntop(nexthop
.mrib_nexthop_addr
.family
,
627 &nexthop
.mrib_nexthop_addr
.u
.prefix
,
628 nexthop_str
, sizeof(nexthop_str
)));
630 if (nexthop
.mrib_nexthop_addr
.family
== AF_INET
)
631 nh_addr
= nexthop
.mrib_nexthop_addr
.u
.prefix4
;
633 /* 6.4 Forwarding Traceroute Requests: ... Otherwise, ... */
635 if (PIM_DEBUG_MTRACE
)
636 zlog_debug("mtrace not found neighbor");
638 rspp
->fwd_code
= MTRACE_FWD_CODE_NO_ROUTE
;
640 rspp
->fwd_code
= fwd_code
;
641 /* 6.5 Sending Traceroute Responses */
642 return mtrace_send_response(pim
, mtracep
, mtrace_len
);
645 out_ifp
= nexthop
.interface
;
646 pim_out_ifp
= out_ifp
->info
;
648 rspp
->incoming
= pim_out_ifp
->primary_address
;
649 rspp
->prev_hop
= nh_addr
;
650 rspp
->in_count
= htonl(MTRACE_UNKNOWN_COUNT
);
651 rspp
->total
= htonl(MTRACE_UNKNOWN_COUNT
);
652 rspp
->rtg_proto
= MTRACE_RTG_PROTO_PIM
;
656 if (nh_addr
.s_addr
== 0) {
657 /* reached source? */
658 if (pim_if_connected_to_source(out_ifp
, mtracep
->src_addr
))
659 return mtrace_send_response(pim
, mtracep
, mtrace_len
);
661 * 6.4 Forwarding Traceroute Requests:
662 * Previous-hop router not known
664 inet_aton(MCAST_ALL_ROUTERS
, &nh_addr
);
667 if (mtracep
->hops
<= (last_rsp_ind
+ 1))
668 return mtrace_send_response(pim
, mtracep
, mtrace_len
);
670 mtracep
->checksum
= 0;
672 mtracep
->checksum
= in_cksum(mtrace_buf
, mtrace_len
);
674 return mtrace_send_packet(out_ifp
, mtracep
, mtrace_len
, nh_addr
,
678 int igmp_mtrace_recv_response(struct igmp_sock
*igmp
, struct ip
*ip_hdr
,
679 struct in_addr from
, const char *from_str
,
680 char *igmp_msg
, int igmp_msg_len
)
682 static uint32_t qry_id
, rsp_dst
;
683 struct interface
*ifp
;
684 struct pim_interface
*pim_ifp
;
685 struct pim_instance
*pim
;
686 struct igmp_mtrace
*mtracep
;
687 uint16_t recv_checksum
;
690 ifp
= igmp
->interface
;
694 mtracep
= (struct igmp_mtrace
*)igmp_msg
;
696 recv_checksum
= mtracep
->checksum
;
698 mtracep
->checksum
= 0;
700 checksum
= in_cksum(igmp_msg
, igmp_msg_len
);
702 if (recv_checksum
!= checksum
) {
703 if (PIM_DEBUG_MTRACE
)
705 "Recv mtrace response from %s on %s: checksum"
706 " mismatch: received=%x computed=%x",
707 from_str
, ifp
->name
, recv_checksum
, checksum
);
711 mtracep
->checksum
= checksum
;
713 if (PIM_DEBUG_MTRACE
)
714 mtrace_debug(pim_ifp
, mtracep
, igmp_msg_len
);
716 /* Drop duplicate packets */
717 if (qry_id
== mtracep
->qry_id
&& rsp_dst
== ip_hdr
->ip_dst
.s_addr
) {
718 if (PIM_DEBUG_MTRACE
)
719 zlog_debug("duplicate mtrace response packet dropped");
723 qry_id
= mtracep
->qry_id
;
724 rsp_dst
= ip_hdr
->ip_dst
.s_addr
;
726 return mtrace_forward_packet(pim
, ip_hdr
);