]> The Tcpdump Group git mirrors - tcpdump/blob - print-bgp.c
projects / tcpdump / blob
summary | shortlog | log | commit | commitdiff | tree
history | raw | HEAD
Revert partially the commit 21b1273
[tcpdump] / print-bgp.c
1 /*
2 * Copyright (C) 1999 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * Extensively modified by Hannes Gredler (hannes@gredler.at) for more
30 * complete BGP support.
31 */
32
33 /* \summary: Border Gateway Protocol (BGP) printer */
34
35 /* specification: RFC 4271 */
36
37 #ifdef HAVE_CONFIG_H
38 #include <config.h>
39 #endif
40
41 #include "netdissect-stdinc.h"
42
43 #include <stdio.h>
44 #include <string.h>
45
46 #include "netdissect.h"
47 #include "addrtoname.h"
48 #include "extract.h"
49 #include "af.h"
50 #include "l2vpn.h"
51
52 struct bgp {
53 nd_byte bgp_marker[16];
54 nd_uint16_t bgp_len;
55 nd_uint8_t bgp_type;
56 };
57 #define BGP_SIZE 19 /* unaligned */
58
59 #define BGP_OPEN 1
60 #define BGP_UPDATE 2
61 #define BGP_NOTIFICATION 3
62 #define BGP_KEEPALIVE 4
63 #define BGP_ROUTE_REFRESH 5
64
65 static const struct tok bgp_msg_values[] = {
66 { BGP_OPEN, "Open"},
67 { BGP_UPDATE, "Update"},
68 { BGP_NOTIFICATION, "Notification"},
69 { BGP_KEEPALIVE, "Keepalive"},
70 { BGP_ROUTE_REFRESH, "Route Refresh"},
71 { 0, NULL}
72 };
73
74 struct bgp_open {
75 nd_byte bgpo_marker[16];
76 nd_uint16_t bgpo_len;
77 nd_uint8_t bgpo_type;
78 nd_uint8_t bgpo_version;
79 nd_uint16_t bgpo_myas;
80 nd_uint16_t bgpo_holdtime;
81 nd_uint32_t bgpo_id;
82 nd_uint8_t bgpo_optlen;
83 /* options should follow */
84 };
85 #define BGP_OPEN_SIZE 29 /* unaligned */
86
87 struct bgp_opt {
88 nd_uint8_t bgpopt_type;
89 nd_uint8_t bgpopt_len;
90 /* variable length */
91 };
92 #define BGP_OPT_SIZE 2 /* some compilers may pad to 4 bytes */
93 #define BGP_CAP_HEADER_SIZE 2 /* some compilers may pad to 4 bytes */
94
95 struct bgp_notification {
96 nd_byte bgpn_marker[16];
97 nd_uint16_t bgpn_len;
98 nd_uint8_t bgpn_type;
99 nd_uint8_t bgpn_major;
100 nd_uint8_t bgpn_minor;
101 };
102 #define BGP_NOTIFICATION_SIZE 21 /* unaligned */
103
104 struct bgp_route_refresh {
105 nd_byte bgp_marker[16];
106 nd_uint16_t len;
107 nd_uint8_t type; /* No padding after this; afi is, in fact, not aligned */
108 nd_uint16_t afi;
109 nd_uint8_t res;
110 nd_uint8_t safi;
111 };
112 #define BGP_ROUTE_REFRESH_SIZE 23
113
114 #define bgp_attr_lenlen(flags, p) \
115 (((flags) & 0x10) ? 2U : 1U)
116 #define bgp_attr_len(flags, p) \
117 (((flags) & 0x10) ? GET_BE_U_2(p) : GET_U_1(p))
118
119 #define BGPTYPE_ORIGIN 1
120 #define BGPTYPE_AS_PATH 2
121 #define BGPTYPE_NEXT_HOP 3
122 #define BGPTYPE_MULTI_EXIT_DISC 4
123 #define BGPTYPE_LOCAL_PREF 5
124 #define BGPTYPE_ATOMIC_AGGREGATE 6
125 #define BGPTYPE_AGGREGATOR 7
126 #define BGPTYPE_COMMUNITIES 8 /* RFC1997 */
127 #define BGPTYPE_ORIGINATOR_ID 9 /* RFC4456 */
128 #define BGPTYPE_CLUSTER_LIST 10 /* RFC4456 */
129 #define BGPTYPE_DPA 11 /* deprecated, draft-ietf-idr-bgp-dpa */
130 #define BGPTYPE_ADVERTISERS 12 /* deprecated RFC1863 */
131 #define BGPTYPE_RCID_PATH 13 /* deprecated RFC1863 */
132 #define BGPTYPE_MP_REACH_NLRI 14 /* RFC4760 */
133 #define BGPTYPE_MP_UNREACH_NLRI 15 /* RFC4760 */
134 #define BGPTYPE_EXTD_COMMUNITIES 16 /* RFC4360 */
135 #define BGPTYPE_AS4_PATH 17 /* RFC6793 */
136 #define BGPTYPE_AGGREGATOR4 18 /* RFC6793 */
137 #define BGPTYPE_PMSI_TUNNEL 22 /* RFC6514 */
138 #define BGPTYPE_TUNNEL_ENCAP 23 /* RFC5512 */
139 #define BGPTYPE_TRAFFIC_ENG 24 /* RFC5543 */
140 #define BGPTYPE_IPV6_EXTD_COMMUNITIES 25 /* RFC5701 */
141 #define BGPTYPE_AIGP 26 /* RFC7311 */
142 #define BGPTYPE_PE_DISTINGUISHER_LABEL 27 /* RFC6514 */
143 #define BGPTYPE_ENTROPY_LABEL 28 /* RFC6790 */
144 #define BGPTYPE_LARGE_COMMUNITY 32 /* draft-ietf-idr-large-community-05 */
145 #define BGPTYPE_ATTR_SET 128 /* RFC6368 */
146
147 #define BGP_MP_NLRI_MINSIZE 3 /* End of RIB Marker detection */
148
149 static const struct tok bgp_attr_values[] = {
150 { BGPTYPE_ORIGIN, "Origin"},
151 { BGPTYPE_AS_PATH, "AS Path"},
152 { BGPTYPE_AS4_PATH, "AS4 Path"},
153 { BGPTYPE_NEXT_HOP, "Next Hop"},
154 { BGPTYPE_MULTI_EXIT_DISC, "Multi Exit Discriminator"},
155 { BGPTYPE_LOCAL_PREF, "Local Preference"},
156 { BGPTYPE_ATOMIC_AGGREGATE, "Atomic Aggregate"},
157 { BGPTYPE_AGGREGATOR, "Aggregator"},
158 { BGPTYPE_AGGREGATOR4, "Aggregator4"},
159 { BGPTYPE_COMMUNITIES, "Community"},
160 { BGPTYPE_ORIGINATOR_ID, "Originator ID"},
161 { BGPTYPE_CLUSTER_LIST, "Cluster List"},
162 { BGPTYPE_DPA, "DPA"},
163 { BGPTYPE_ADVERTISERS, "Advertisers"},
164 { BGPTYPE_RCID_PATH, "RCID Path / Cluster ID"},
165 { BGPTYPE_MP_REACH_NLRI, "Multi-Protocol Reach NLRI"},
166 { BGPTYPE_MP_UNREACH_NLRI, "Multi-Protocol Unreach NLRI"},
167 { BGPTYPE_EXTD_COMMUNITIES, "Extended Community"},
168 { BGPTYPE_PMSI_TUNNEL, "PMSI Tunnel"},
169 { BGPTYPE_TUNNEL_ENCAP, "Tunnel Encapsulation"},
170 { BGPTYPE_TRAFFIC_ENG, "Traffic Engineering"},
171 { BGPTYPE_IPV6_EXTD_COMMUNITIES, "IPv6 Extended Community"},
172 { BGPTYPE_AIGP, "Accumulated IGP Metric"},
173 { BGPTYPE_PE_DISTINGUISHER_LABEL, "PE Distinguisher Label"},
174 { BGPTYPE_ENTROPY_LABEL, "Entropy Label"},
175 { BGPTYPE_LARGE_COMMUNITY, "Large Community"},
176 { BGPTYPE_ATTR_SET, "Attribute Set"},
177 { 255, "Reserved for development"},
178 { 0, NULL}
179 };
180
181 #define BGP_AS_SET 1
182 #define BGP_AS_SEQUENCE 2
183 #define BGP_CONFED_AS_SEQUENCE 3 /* draft-ietf-idr-rfc3065bis-01 */
184 #define BGP_CONFED_AS_SET 4 /* draft-ietf-idr-rfc3065bis-01 */
185
186 #define BGP_AS_SEG_TYPE_MIN BGP_AS_SET
187 #define BGP_AS_SEG_TYPE_MAX BGP_CONFED_AS_SET
188
189 static const struct tok bgp_as_path_segment_open_values[] = {
190 { BGP_AS_SEQUENCE, ""},
191 { BGP_AS_SET, "{ "},
192 { BGP_CONFED_AS_SEQUENCE, "( "},
193 { BGP_CONFED_AS_SET, "({ "},
194 { 0, NULL}
195 };
196
197 static const struct tok bgp_as_path_segment_close_values[] = {
198 { BGP_AS_SEQUENCE, ""},
199 { BGP_AS_SET, "}"},
200 { BGP_CONFED_AS_SEQUENCE, ")"},
201 { BGP_CONFED_AS_SET, "})"},
202 { 0, NULL}
203 };
204
205 #define BGP_OPT_AUTH 1
206 #define BGP_OPT_CAP 2
207
208 static const struct tok bgp_opt_values[] = {
209 { BGP_OPT_AUTH, "Authentication Information"},
210 { BGP_OPT_CAP, "Capabilities Advertisement"},
211 { 0, NULL}
212 };
213
214 #define BGP_CAPCODE_MP 1 /* RFC2858 */
215 #define BGP_CAPCODE_RR 2 /* RFC2918 */
216 #define BGP_CAPCODE_ORF 3 /* RFC5291 */
217 #define BGP_CAPCODE_MR 4 /* RFC3107 */
218 #define BGP_CAPCODE_EXT_NH 5 /* RFC5549 */
219 #define BGP_CAPCODE_ML 8 /* RFC8277 */
220 #define BGP_CAPCODE_RESTART 64 /* RFC4724 */
221 #define BGP_CAPCODE_AS_NEW 65 /* RFC6793 */
222 #define BGP_CAPCODE_DYN_CAP 67 /* draft-ietf-idr-dynamic-cap */
223 #define BGP_CAPCODE_MULTISESS 68 /* draft-ietf-idr-bgp-multisession */
224 #define BGP_CAPCODE_ADD_PATH 69 /* RFC7911 */
225 #define BGP_CAPCODE_ENH_RR 70 /* draft-keyur-bgp-enhanced-route-refresh */
226 #define BGP_CAPCODE_LLGR 71 /* draft-uttaro-idr-bgp-persistence-05 */
227 #define BGP_CAPCODE_RR_CISCO 128
228
229 static const struct tok bgp_capcode_values[] = {
230 { BGP_CAPCODE_MP, "Multiprotocol Extensions"},
231 { BGP_CAPCODE_RR, "Route Refresh"},
232 { BGP_CAPCODE_ORF, "Cooperative Route Filtering"},
233 { BGP_CAPCODE_MR, "Multiple Routes to a Destination"},
234 { BGP_CAPCODE_EXT_NH, "Extended Next Hop Encoding"},
235 { BGP_CAPCODE_ML, "Multiple Labels"},
236 { BGP_CAPCODE_RESTART, "Graceful Restart"},
237 { BGP_CAPCODE_AS_NEW, "32-Bit AS Number"},
238 { BGP_CAPCODE_DYN_CAP, "Dynamic Capability"},
239 { BGP_CAPCODE_MULTISESS, "Multisession BGP"},
240 { BGP_CAPCODE_ADD_PATH, "Multiple Paths"},
241 { BGP_CAPCODE_ENH_RR, "Enhanced Route Refresh"},
242 { BGP_CAPCODE_LLGR, "Long-lived Graceful Restart"},
243 { BGP_CAPCODE_RR_CISCO, "Route Refresh (Cisco)"},
244 { 0, NULL}
245 };
246
247 #define BGP_NOTIFY_MAJOR_MSG 1
248 #define BGP_NOTIFY_MAJOR_OPEN 2
249 #define BGP_NOTIFY_MAJOR_UPDATE 3
250 #define BGP_NOTIFY_MAJOR_HOLDTIME 4
251 #define BGP_NOTIFY_MAJOR_FSM 5
252 #define BGP_NOTIFY_MAJOR_CEASE 6
253 #define BGP_NOTIFY_MAJOR_CAP 7
254
255 static const struct tok bgp_notify_major_values[] = {
256 { BGP_NOTIFY_MAJOR_MSG, "Message Header Error"},
257 { BGP_NOTIFY_MAJOR_OPEN, "OPEN Message Error"},
258 { BGP_NOTIFY_MAJOR_UPDATE, "UPDATE Message Error"},
259 { BGP_NOTIFY_MAJOR_HOLDTIME,"Hold Timer Expired"},
260 { BGP_NOTIFY_MAJOR_FSM, "Finite State Machine Error"},
261 { BGP_NOTIFY_MAJOR_CEASE, "Cease"},
262 { BGP_NOTIFY_MAJOR_CAP, "Capability Message Error"},
263 { 0, NULL}
264 };
265
266 /* draft-ietf-idr-cease-subcode-02 */
267 #define BGP_NOTIFY_MINOR_CEASE_MAXPRFX 1
268 /* draft-ietf-idr-shutdown-07 */
269 #define BGP_NOTIFY_MINOR_CEASE_SHUT 2
270 #define BGP_NOTIFY_MINOR_CEASE_RESET 4
271 #define BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN 128
272 static const struct tok bgp_notify_minor_cease_values[] = {
273 { BGP_NOTIFY_MINOR_CEASE_MAXPRFX, "Maximum Number of Prefixes Reached"},
274 { BGP_NOTIFY_MINOR_CEASE_SHUT, "Administrative Shutdown"},
275 { 3, "Peer Unconfigured"},
276 { BGP_NOTIFY_MINOR_CEASE_RESET, "Administrative Reset"},
277 { 5, "Connection Rejected"},
278 { 6, "Other Configuration Change"},
279 { 7, "Connection Collision Resolution"},
280 { 0, NULL}
281 };
282
283 static const struct tok bgp_notify_minor_msg_values[] = {
284 { 1, "Connection Not Synchronized"},
285 { 2, "Bad Message Length"},
286 { 3, "Bad Message Type"},
287 { 0, NULL}
288 };
289
290 static const struct tok bgp_notify_minor_open_values[] = {
291 { 1, "Unsupported Version Number"},
292 { 2, "Bad Peer AS"},
293 { 3, "Bad BGP Identifier"},
294 { 4, "Unsupported Optional Parameter"},
295 { 5, "Authentication Failure"},
296 { 6, "Unacceptable Hold Time"},
297 { 7, "Capability Message Error"},
298 { 0, NULL}
299 };
300
301 static const struct tok bgp_notify_minor_update_values[] = {
302 { 1, "Malformed Attribute List"},
303 { 2, "Unrecognized Well-known Attribute"},
304 { 3, "Missing Well-known Attribute"},
305 { 4, "Attribute Flags Error"},
306 { 5, "Attribute Length Error"},
307 { 6, "Invalid ORIGIN Attribute"},
308 { 7, "AS Routing Loop"},
309 { 8, "Invalid NEXT_HOP Attribute"},
310 { 9, "Optional Attribute Error"},
311 { 10, "Invalid Network Field"},
312 { 11, "Malformed AS_PATH"},
313 { 0, NULL}
314 };
315
316 static const struct tok bgp_notify_minor_fsm_values[] = {
317 { 0, "Unspecified Error"},
318 { 1, "In OpenSent State"},
319 { 2, "In OpenConfirm State"},
320 { 3, "In Established State"},
321 { 0, NULL }
322 };
323
324 static const struct tok bgp_notify_minor_cap_values[] = {
325 { 1, "Invalid Action Value" },
326 { 2, "Invalid Capability Length" },
327 { 3, "Malformed Capability Value" },
328 { 4, "Unsupported Capability Code" },
329 { 0, NULL }
330 };
331
332 static const struct tok bgp_origin_values[] = {
333 { 0, "IGP"},
334 { 1, "EGP"},
335 { 2, "Incomplete"},
336 { 0, NULL}
337 };
338
339 #define BGP_PMSI_TUNNEL_RSVP_P2MP 1
340 #define BGP_PMSI_TUNNEL_LDP_P2MP 2
341 #define BGP_PMSI_TUNNEL_PIM_SSM 3
342 #define BGP_PMSI_TUNNEL_PIM_SM 4
343 #define BGP_PMSI_TUNNEL_PIM_BIDIR 5
344 #define BGP_PMSI_TUNNEL_INGRESS 6
345 #define BGP_PMSI_TUNNEL_LDP_MP2MP 7
346
347 static const struct tok bgp_pmsi_tunnel_values[] = {
348 { BGP_PMSI_TUNNEL_RSVP_P2MP, "RSVP-TE P2MP LSP"},
349 { BGP_PMSI_TUNNEL_LDP_P2MP, "LDP P2MP LSP"},
350 { BGP_PMSI_TUNNEL_PIM_SSM, "PIM-SSM Tree"},
351 { BGP_PMSI_TUNNEL_PIM_SM, "PIM-SM Tree"},
352 { BGP_PMSI_TUNNEL_PIM_BIDIR, "PIM-Bidir Tree"},
353 { BGP_PMSI_TUNNEL_INGRESS, "Ingress Replication"},
354 { BGP_PMSI_TUNNEL_LDP_MP2MP, "LDP MP2MP LSP"},
355 { 0, NULL}
356 };
357
358 static const struct tok bgp_pmsi_flag_values[] = {
359 { 0x01, "Leaf Information required"},
360 { 0, NULL}
361 };
362
363 #define BGP_AIGP_TLV 1
364
365 static const struct tok bgp_aigp_values[] = {
366 { BGP_AIGP_TLV, "AIGP"},
367 { 0, NULL}
368 };
369
370 /* Subsequent address family identifier, RFC2283 section 7 */
371 #define SAFNUM_RES 0
372 #define SAFNUM_UNICAST 1
373 #define SAFNUM_MULTICAST 2
374 #define SAFNUM_UNIMULTICAST 3 /* deprecated now */
375 /* labeled BGP RFC3107 */
376 #define SAFNUM_LABUNICAST 4
377 /* RFC6514 */
378 #define SAFNUM_MULTICAST_VPN 5
379 /* draft-nalawade-kapoor-tunnel-safi */
380 #define SAFNUM_TUNNEL 64
381 /* RFC4761 */
382 #define SAFNUM_VPLS 65
383 /* RFC6037 */
384 #define SAFNUM_MDT 66
385 /* RFC7432 */
386 #define SAFNUM_EVPN 70
387 /* RFC4364 */
388 #define SAFNUM_VPNUNICAST 128
389 /* RFC6513 */
390 #define SAFNUM_VPNMULTICAST 129
391 #define SAFNUM_VPNUNIMULTICAST 130 /* deprecated now */
392 /* RFC4684 */
393 #define SAFNUM_RT_ROUTING_INFO 132
394
395 #define BGP_VPN_RD_LEN 8
396
397 static const struct tok bgp_safi_values[] = {
398 { SAFNUM_RES, "Reserved"},
399 { SAFNUM_UNICAST, "Unicast"},
400 { SAFNUM_MULTICAST, "Multicast"},
401 { SAFNUM_UNIMULTICAST, "Unicast+Multicast"},
402 { SAFNUM_LABUNICAST, "labeled Unicast"},
403 { SAFNUM_TUNNEL, "Tunnel"},
404 { SAFNUM_VPLS, "VPLS"},
405 { SAFNUM_MDT, "MDT"},
406 { SAFNUM_EVPN, "EVPN"},
407 { SAFNUM_VPNUNICAST, "labeled VPN Unicast"},
408 { SAFNUM_VPNMULTICAST, "labeled VPN Multicast"},
409 { SAFNUM_VPNUNIMULTICAST, "labeled VPN Unicast+Multicast"},
410 { SAFNUM_RT_ROUTING_INFO, "Route Target Routing Information"},
411 { SAFNUM_MULTICAST_VPN, "Multicast VPN"},
412 { 0, NULL }
413 };
414
415 /* well-known community */
416 #define BGP_COMMUNITY_NO_EXPORT 0xffffff01
417 #define BGP_COMMUNITY_NO_ADVERT 0xffffff02
418 #define BGP_COMMUNITY_NO_EXPORT_SUBCONFED 0xffffff03
419
420 /* Extended community type - RFC 4360 */
421 #define BGP_EXT_COM_RT_0 0x0002 /* Route Target,Format AS(2bytes):AN(4bytes) */
422 #define BGP_EXT_COM_RT_1 0x0102 /* Route Target,Format IP address:AN(2bytes) */
423 #define BGP_EXT_COM_RT_2 0x0202 /* Route Target,Format AN(4bytes):local(2bytes) */
424 #define BGP_EXT_COM_RO_0 0x0003 /* Route Origin,Format AS(2bytes):AN(4bytes) */
425 #define BGP_EXT_COM_RO_1 0x0103 /* Route Origin,Format IP address:AN(2bytes) */
426 #define BGP_EXT_COM_RO_2 0x0203 /* Route Origin,Format AN(4bytes):local(2bytes) */
427 #define BGP_EXT_COM_LINKBAND 0x4004 /* Link Bandwidth,Format AS(2B):Bandwidth(4B) */
428 /* rfc2547 bgp-mpls-vpns */
429 #define BGP_EXT_COM_VPN_ORIGIN 0x0005 /* OSPF Domain ID / VPN of Origin - draft-rosen-vpns-ospf-bgp-mpls */
430 #define BGP_EXT_COM_VPN_ORIGIN2 0x0105 /* duplicate - keep for backwards compatibility */
431 #define BGP_EXT_COM_VPN_ORIGIN3 0x0205 /* duplicate - keep for backwards compatibility */
432 #define BGP_EXT_COM_VPN_ORIGIN4 0x8005 /* duplicate - keep for backwards compatibility */
433
434 #define BGP_EXT_COM_OSPF_RTYPE 0x0306 /* OSPF Route Type,Format Area(4B):RouteType(1B):Options(1B) */
435 #define BGP_EXT_COM_OSPF_RTYPE2 0x8000 /* duplicate - keep for backwards compatibility */
436 #define BGP_EXT_COM_ENCAP 0x030c /* rfc5512 */
437
438 #define BGP_EXT_COM_OSPF_RID 0x0107 /* OSPF Router ID,Format RouterID(4B):Unused(2B) */
439 #define BGP_EXT_COM_OSPF_RID2 0x8001 /* duplicate - keep for backwards compatibility */
440
441 #define BGP_EXT_COM_L2INFO 0x800a /* draft-kompella-ppvpn-l2vpn */
442
443 #define BGP_EXT_COM_SOURCE_AS 0x0009 /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */
444 #define BGP_EXT_COM_VRF_RT_IMP 0x010b /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */
445 #define BGP_EXT_COM_L2VPN_RT_0 0x000a /* L2VPN Identifier,Format AS(2bytes):AN(4bytes) */
446 #define BGP_EXT_COM_L2VPN_RT_1 0xF10a /* L2VPN Identifier,Format IP address:AN(2bytes) */
447
448 /* https://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a00801eb09a.shtml */
449 #define BGP_EXT_COM_EIGRP_GEN 0x8800
450 #define BGP_EXT_COM_EIGRP_METRIC_AS_DELAY 0x8801
451 #define BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW 0x8802
452 #define BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU 0x8803
453 #define BGP_EXT_COM_EIGRP_EXT_REMAS_REMID 0x8804
454 #define BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC 0x8805
455
456 static const struct tok bgp_extd_comm_flag_values[] = {
457 { 0x8000, "vendor-specific"},
458 { 0x4000, "non-transitive"},
459 { 0, NULL},
460 };
461
462 static const struct tok bgp_extd_comm_subtype_values[] = {
463 { BGP_EXT_COM_RT_0, "target"},
464 { BGP_EXT_COM_RT_1, "target"},
465 { BGP_EXT_COM_RT_2, "target"},
466 { BGP_EXT_COM_RO_0, "origin"},
467 { BGP_EXT_COM_RO_1, "origin"},
468 { BGP_EXT_COM_RO_2, "origin"},
469 { BGP_EXT_COM_LINKBAND, "link-BW"},
470 { BGP_EXT_COM_VPN_ORIGIN, "ospf-domain"},
471 { BGP_EXT_COM_VPN_ORIGIN2, "ospf-domain"},
472 { BGP_EXT_COM_VPN_ORIGIN3, "ospf-domain"},
473 { BGP_EXT_COM_VPN_ORIGIN4, "ospf-domain"},
474 { BGP_EXT_COM_OSPF_RTYPE, "ospf-route-type"},
475 { BGP_EXT_COM_OSPF_RTYPE2, "ospf-route-type"},
476 { BGP_EXT_COM_ENCAP, "encapsulation"},
477 { BGP_EXT_COM_OSPF_RID, "ospf-router-id"},
478 { BGP_EXT_COM_OSPF_RID2, "ospf-router-id"},
479 { BGP_EXT_COM_L2INFO, "layer2-info"},
480 { BGP_EXT_COM_EIGRP_GEN, "eigrp-general-route (flag, tag)" },
481 { BGP_EXT_COM_EIGRP_METRIC_AS_DELAY, "eigrp-route-metric (AS, delay)" },
482 { BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW, "eigrp-route-metric (reliability, nexthop, bandwidth)" },
483 { BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU, "eigrp-route-metric (load, MTU)" },
484 { BGP_EXT_COM_EIGRP_EXT_REMAS_REMID, "eigrp-external-route (remote-AS, remote-ID)" },
485 { BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC, "eigrp-external-route (remote-proto, remote-metric)" },
486 { BGP_EXT_COM_SOURCE_AS, "source-AS" },
487 { BGP_EXT_COM_VRF_RT_IMP, "vrf-route-import"},
488 { BGP_EXT_COM_L2VPN_RT_0, "l2vpn-id"},
489 { BGP_EXT_COM_L2VPN_RT_1, "l2vpn-id"},
490 { 0, NULL},
491 };
492
493 /* RFC RFC5512 BGP Tunnel Encapsulation Attribute Tunnel Types */
494 #define BGP_ENCAP_TUNNEL_L2TPV3_IP 1
495 #define BGP_ENCAP_TUNNEL_GRE 2
496 #define BGP_ENCAP_TUNNEL_TRANSMIT 3
497 #define BGP_ENCAP_TUNNEL_IPSEC 4
498 #define BGP_ENCAP_TUNNEL_IP_IPSEC 5
499 #define BGP_ENCAP_TUNNEL_MPLS_IP 6
500 #define BGP_ENCAP_TUNNEL_IP_IP 7
501 #define BGP_ENCAP_TUNNEL_VXLAN 8
502 #define BGP_ENCAP_TUNNEL_NVGRE 9
503 #define BGP_ENCAP_TUNNEL_MPLS 10
504 #define BGP_ENCAP_TUNNEL_MPLS_GRE 11
505 #define BGP_ENCAP_TUNNEL_VXLAN_GPE 12
506 #define BGP_ENCAP_TUNNEL_MPLS_UDP 13
507 #define BGP_ENCAP_TUNNEL_IPV6 14
508 #define BGP_ENCAP_TUNNEL_SR_TE 15
509 #define BGP_ENCAP_TUNNEL_BARE 16
510 #define BGP_ENCAP_TUNNEL_SR 17
511
512 static const struct tok bgp_extd_comm_encap_tunnel_values[] = {
513 { BGP_ENCAP_TUNNEL_L2TPV3_IP, "L2TPv3 over IP"},
514 { BGP_ENCAP_TUNNEL_GRE, "GRE"},
515 { BGP_ENCAP_TUNNEL_TRANSMIT, "Transmit Tunnel"},
516 { BGP_ENCAP_TUNNEL_IPSEC, "IPsec"},
517 { BGP_ENCAP_TUNNEL_IP_IPSEC, "IP in IP with IPsec"},
518 { BGP_ENCAP_TUNNEL_MPLS_IP, "MPLS in IP with IPsec"},
519 { BGP_ENCAP_TUNNEL_IP_IP, "IP in IP"},
520 { BGP_ENCAP_TUNNEL_VXLAN, "VXLAN"},
521 { BGP_ENCAP_TUNNEL_NVGRE, "NVGRE"},
522 { BGP_ENCAP_TUNNEL_MPLS, "MPLS"},
523 { BGP_ENCAP_TUNNEL_MPLS_GRE, "MPLS in GRE"},
524 { BGP_ENCAP_TUNNEL_VXLAN_GPE, "VXLAN GPE"},
525 { BGP_ENCAP_TUNNEL_MPLS_UDP, "MPLS in UDP"},
526 { BGP_ENCAP_TUNNEL_IPV6, "IPv6"},
527 { BGP_ENCAP_TUNNEL_SR_TE, "SR TE"},
528 { BGP_ENCAP_TUNNEL_BARE, "Bare"},
529 { BGP_ENCAP_TUNNEL_SR, "SR"},
530 { 0, NULL},
531 };
532
533 /* OSPF codes for BGP_EXT_COM_OSPF_RTYPE draft-rosen-vpns-ospf-bgp-mpls */
534 #define BGP_OSPF_RTYPE_RTR 1 /* OSPF Router LSA */
535 #define BGP_OSPF_RTYPE_NET 2 /* OSPF Network LSA */
536 #define BGP_OSPF_RTYPE_SUM 3 /* OSPF Summary LSA */
537 #define BGP_OSPF_RTYPE_EXT 5 /* OSPF External LSA, note that ASBR doesn't apply to MPLS-VPN */
538 #define BGP_OSPF_RTYPE_NSSA 7 /* OSPF NSSA External*/
539 #define BGP_OSPF_RTYPE_SHAM 129 /* OSPF-MPLS-VPN Sham link */
540 #define BGP_OSPF_RTYPE_METRIC_TYPE 0x1 /* LSB of RTYPE Options Field */
541
542 static const struct tok bgp_extd_comm_ospf_rtype_values[] = {
543 { BGP_OSPF_RTYPE_RTR, "Router" },
544 { BGP_OSPF_RTYPE_NET, "Network" },
545 { BGP_OSPF_RTYPE_SUM, "Summary" },
546 { BGP_OSPF_RTYPE_EXT, "External" },
547 { BGP_OSPF_RTYPE_NSSA,"NSSA External" },
548 { BGP_OSPF_RTYPE_SHAM,"MPLS-VPN Sham" },
549 { 0, NULL },
550 };
551
552 /* ADD-PATH Send/Receive field values */
553 static const struct tok bgp_add_path_recvsend[] = {
554 { 1, "Receive" },
555 { 2, "Send" },
556 { 3, "Both" },
557 { 0, NULL },
558 };
559
560 /* allocate space for the largest possible string */
561 static char astostr[sizeof("xxxxx.xxxxx")];
562
563 /*
564 * as_printf
565 *
566 * Convert an AS number into a string and return string pointer.
567 *
568 * Depending on bflag is set or not, AS number is converted into ASDOT notation
569 * or plain number notation.
570 *
571 */
572 static char *
573 as_printf(netdissect_options *ndo,
574 char *str, size_t size, u_int asnum)
575 {
576 if (!ndo->ndo_bflag || asnum <= 0xFFFF) {
577 snprintf(str, size, "%u", asnum);
578 } else {
579 snprintf(str, size, "%u.%u", asnum >> 16, asnum & 0xFFFF);
580 }
581 return str;
582 }
583
584 #define ITEMCHECK(minlen) if (itemlen < minlen) goto badtlv;
585
586 int
587 decode_prefix4(netdissect_options *ndo,
588 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
589 {
590 nd_ipv4 addr;
591 u_int plen, plenbytes;
592
593 ITEMCHECK(1);
594 plen = GET_U_1(pptr);
595 if (32 < plen)
596 return -1;
597 itemlen -= 1;
598
599 memset(&addr, 0, sizeof(addr));
600 plenbytes = (plen + 7) / 8;
601 ND_TCHECK_LEN(pptr + 1, plenbytes);
602 ITEMCHECK(plenbytes);
603 memcpy(&addr, pptr + 1, plenbytes);
604 if (plen % 8) {
605 ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
606 }
607 snprintf(buf, buflen, "%s/%u", ipaddr_string(ndo, (const u_char *)&addr), plen);
608 return 1 + plenbytes;
609
610 trunc:
611 return -2;
612
613 badtlv:
614 return -3;
615 }
616
617 static int
618 decode_labeled_prefix4(netdissect_options *ndo,
619 const u_char *pptr, u_int itemlen, char *buf,
620 size_t buflen)
621 {
622 nd_ipv4 addr;
623 u_int plen, plenbytes;
624
625 /* prefix length and label = 4 bytes */
626 ND_TCHECK_4(pptr);
627 ITEMCHECK(4);
628 plen = GET_U_1(pptr); /* get prefix length */
629
630 /* this is one of the weirdnesses of rfc3107
631 the label length (actually the label + COS bits)
632 is added to the prefix length;
633 we also do only read out just one label -
634 there is no real application for advertisement of
635 stacked labels in a single BGP message
636 */
637
638 if (24 > plen)
639 return -1;
640
641 plen-=24; /* adjust prefixlen - labellength */
642
643 if (32 < plen)
644 return -1;
645 itemlen -= 4;
646
647 memset(&addr, 0, sizeof(addr));
648 plenbytes = (plen + 7) / 8;
649 ND_TCHECK_LEN(pptr + 4, plenbytes);
650 ITEMCHECK(plenbytes);
651 memcpy(&addr, pptr + 4, plenbytes);
652 if (plen % 8) {
653 ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
654 }
655 /* the label may get offsetted by 4 bits so lets shift it right */
656 snprintf(buf, buflen, "%s/%u, label:%u %s",
657 ipaddr_string(ndo, (const u_char *)&addr),
658 plen,
659 GET_BE_U_3(pptr + 1)>>4,
660 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
661
662 return 4 + plenbytes;
663
664 trunc:
665 return -2;
666
667 badtlv:
668 return -3;
669 }
670
671 /*
672 * bgp_vpn_ip_print
673 *
674 * print an ipv4 or ipv6 address into a buffer dependend on address length.
675 */
676 static char *
677 bgp_vpn_ip_print(netdissect_options *ndo,
678 const u_char *pptr, u_int addr_length)
679 {
680
681 /* worst case string is s fully formatted v6 address */
682 static char addr[sizeof("1234:5678:89ab:cdef:1234:5678:89ab:cdef")];
683 char *pos = addr;
684
685 switch(addr_length) {
686 case (sizeof(nd_ipv4) << 3): /* 32 */
687 snprintf(pos, sizeof(addr), "%s", GET_IPADDR_STRING(pptr));
688 break;
689 case (sizeof(nd_ipv6) << 3): /* 128 */
690 snprintf(pos, sizeof(addr), "%s", GET_IP6ADDR_STRING(pptr));
691 break;
692 default:
693 snprintf(pos, sizeof(addr), "bogus address length %u", addr_length);
694 break;
695 }
696 pos += strlen(pos);
697
698 *(pos) = '\0';
699 return (addr);
700 }
701
702 /*
703 * bgp_vpn_sg_print
704 *
705 * print an multicast s,g entry into a buffer.
706 * the s,g entry is encoded like this.
707 *
708 * +-----------------------------------+
709 * | Multicast Source Length (1 octet) |
710 * +-----------------------------------+
711 * | Multicast Source (Variable) |
712 * +-----------------------------------+
713 * | Multicast Group Length (1 octet) |
714 * +-----------------------------------+
715 * | Multicast Group (Variable) |
716 * +-----------------------------------+
717 *
718 * return the number of bytes read from the wire.
719 */
720 static u_int
721 bgp_vpn_sg_print(netdissect_options *ndo,
722 const u_char *pptr, char *buf, size_t buflen)
723 {
724 uint8_t addr_length;
725 u_int total_length, offset;
726
727 total_length = 0;
728
729 /* Source address length, encoded in bits */
730 addr_length = GET_U_1(pptr);
731 pptr++;
732
733 /* Source address */
734 ND_TCHECK_LEN(pptr, (addr_length >> 3));
735 total_length += (addr_length >> 3) + 1;
736 offset = (u_int)strlen(buf);
737 if (addr_length) {
738 snprintf(buf + offset, buflen - offset, ", Source %s",
739 bgp_vpn_ip_print(ndo, pptr, addr_length));
740 pptr += (addr_length >> 3);
741 }
742
743 /* Group address length, encoded in bits */
744 addr_length = GET_U_1(pptr);
745 pptr++;
746
747 /* Group address */
748 ND_TCHECK_LEN(pptr, (addr_length >> 3));
749 total_length += (addr_length >> 3) + 1;
750 offset = (u_int)strlen(buf);
751 if (addr_length) {
752 snprintf(buf + offset, buflen - offset, ", Group %s",
753 bgp_vpn_ip_print(ndo, pptr, addr_length));
754 pptr += (addr_length >> 3);
755 }
756
757 trunc:
758 return (total_length);
759 }
760
761 /* Print an RFC 4364 Route Distinguisher */
762 const char *
763 bgp_vpn_rd_print(netdissect_options *ndo,
764 const u_char *pptr)
765 {
766 /* allocate space for the largest possible string */
767 static char rd[sizeof("xxxxx.xxxxx:xxxxx (xxx.xxx.xxx.xxx:xxxxx)")];
768 char *pos = rd;
769
770 /* ok lets load the RD format */
771 switch (GET_BE_U_2(pptr)) {
772
773 case 0:
774 /* 2-byte-AS:number fmt */
775 snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (= %u.%u.%u.%u)",
776 GET_BE_U_2(pptr + 2),
777 GET_BE_U_4(pptr + 4),
778 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
779 GET_U_1(pptr + 6), GET_U_1(pptr + 7));
780 break;
781
782 case 1:
783 /* IP-address:AS fmt */
784 snprintf(pos, sizeof(rd) - (pos - rd), "%u.%u.%u.%u:%u",
785 GET_U_1(pptr + 2), GET_U_1(pptr + 3),
786 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
787 GET_BE_U_2(pptr + 6));
788 break;
789
790 case 2:
791 /* 4-byte-AS:number fmt */
792 snprintf(pos, sizeof(rd) - (pos - rd), "%s:%u (%u.%u.%u.%u:%u)",
793 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 2)),
794 GET_BE_U_2(pptr + 6), GET_U_1(pptr + 2),
795 GET_U_1(pptr + 3), GET_U_1(pptr + 4),
796 GET_U_1(pptr + 5), GET_BE_U_2(pptr + 6));
797 break;
798 default:
799 snprintf(pos, sizeof(rd) - (pos - rd), "unknown RD format");
800 break;
801 }
802 pos += strlen(pos);
803 *(pos) = '\0';
804 return (rd);
805 }
806
807 /*
808 * Print an RFC 4360 Extended Community.
809 */
810 static void
811 bgp_extended_community_print(netdissect_options *ndo,
812 const u_char *pptr)
813 {
814 union { /* copy buffer for bandwidth values */
815 float f;
816 uint32_t i;
817 } bw;
818
819 switch (GET_BE_U_2(pptr)) {
820
821 case BGP_EXT_COM_RT_0:
822 case BGP_EXT_COM_RO_0:
823 case BGP_EXT_COM_L2VPN_RT_0:
824 ND_PRINT("%u:%u (= %s)",
825 GET_BE_U_2(pptr + 2),
826 GET_BE_U_4(pptr + 4),
827 GET_IPADDR_STRING(pptr+4));
828 break;
829
830 case BGP_EXT_COM_RT_1:
831 case BGP_EXT_COM_RO_1:
832 case BGP_EXT_COM_L2VPN_RT_1:
833 case BGP_EXT_COM_VRF_RT_IMP:
834 ND_PRINT("%s:%u",
835 GET_IPADDR_STRING(pptr+2),
836 GET_BE_U_2(pptr + 6));
837 break;
838
839 case BGP_EXT_COM_RT_2:
840 case BGP_EXT_COM_RO_2:
841 ND_PRINT("%s:%u",
842 as_printf(ndo, astostr, sizeof(astostr),
843 GET_BE_U_4(pptr + 2)), GET_BE_U_2(pptr + 6));
844 break;
845
846 case BGP_EXT_COM_LINKBAND:
847 bw.i = GET_BE_U_4(pptr + 2);
848 ND_PRINT("bandwidth: %.3f Mbps",
849 bw.f*8/1000000);
850 break;
851
852 case BGP_EXT_COM_VPN_ORIGIN:
853 case BGP_EXT_COM_VPN_ORIGIN2:
854 case BGP_EXT_COM_VPN_ORIGIN3:
855 case BGP_EXT_COM_VPN_ORIGIN4:
856 case BGP_EXT_COM_OSPF_RID:
857 case BGP_EXT_COM_OSPF_RID2:
858 ND_PRINT("%s", GET_IPADDR_STRING(pptr+2));
859 break;
860
861 case BGP_EXT_COM_OSPF_RTYPE:
862 case BGP_EXT_COM_OSPF_RTYPE2:
863 ND_PRINT("area:%s, router-type:%s, metric-type:%s%s",
864 GET_IPADDR_STRING(pptr+2),
865 tok2str(bgp_extd_comm_ospf_rtype_values,
866 "unknown (0x%02x)",
867 GET_U_1((pptr + 6))),
868 (GET_U_1(pptr + 7) & BGP_OSPF_RTYPE_METRIC_TYPE) ? "E2" : "",
869 ((GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_EXT) || (GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_NSSA)) ? "E1" : "");
870 break;
871
872 case BGP_EXT_COM_L2INFO:
873 ND_PRINT("%s Control Flags [0x%02x]:MTU %u",
874 tok2str(l2vpn_encaps_values,
875 "unknown encaps",
876 GET_U_1((pptr + 2))),
877 GET_U_1((pptr + 3)),
878 GET_BE_U_2(pptr + 4));
879 break;
880
881 case BGP_EXT_COM_SOURCE_AS:
882 ND_PRINT("AS %u", GET_BE_U_2(pptr + 2));
883 break;
884
885 case BGP_EXT_COM_ENCAP:
886 ND_PRINT("Tunnel type: %s", tok2str(bgp_extd_comm_encap_tunnel_values,
887 "unknown encaps",
888 GET_BE_U_2(pptr + 6)));
889 break;
890
891 default:
892 ND_PRINT("%02x%02x%02x%02x%02x%02x",
893 GET_U_1(pptr + 2),
894 GET_U_1(pptr + 3),
895 GET_U_1(pptr + 4),
896 GET_U_1(pptr + 5),
897 GET_U_1(pptr + 6),
898 GET_U_1(pptr + 7));
899 break;
900 }
901 }
902
903 /*
904 * RFC4684 (Section 4)/RFC2858 (Section 4).
905 * RTC membership prefix is structured as follows
906 * [prefix-len] [origin-as] [route-target]
907 * The route-target is encoded as RT ext-comms.
908 * Prefix-len may be 0, 32..96
909 *
910 * Note that pptr is not packet data - it is
911 * a buffer owned by our caller - therefore GET_*
912 * macros can not be used.
913 */
914 static char *
915 bgp_rt_prefix_print(netdissect_options *ndo,
916 const u_char *pptr,
917 u_int plen)
918 {
919 /* allocate space for the largest possible string */
920 char rtc_prefix_in_hex[20] = "";
921 u_int rtc_prefix_in_hex_len = 0;
922 static char output[61]; /* max response string */
923 uint16_t ec_type = 0;
924 u_int octet_count;
925 u_int i;
926
927 if (plen == 0) {
928 snprintf(output, sizeof(output), "route-target: 0:0/0");
929 return (output);
930 }
931
932 /* hex representation of the prefix */
933 octet_count = (plen+7)/8;
934 for (i=0; i<octet_count; i++) {
935 rtc_prefix_in_hex_len += snprintf(rtc_prefix_in_hex+rtc_prefix_in_hex_len,
936 sizeof(rtc_prefix_in_hex)-rtc_prefix_in_hex_len,
937 "%02x%s", *(pptr+i),
938 ((i%2 == 1) && (i<octet_count-1)) ? " " : "");
939 }
940
941 if (plen < 16) {
942 /*
943 * The prefix is too short to include the full ext-comm type,
944 * so we have no way to parse it further.
945 */
946 snprintf(output, sizeof(output), "route-target: partial-type: (%s/%d)",
947 rtc_prefix_in_hex, plen);
948 return (output);
949 }
950
951 /*
952 * get the ext-comm type
953 * Note: pptr references a static 8 octet buffer with unused bits set to 0,
954 * hense EXTRACT_*() macros are safe.
955 */
956 ec_type = EXTRACT_BE_U_2(pptr);
957 switch (ec_type) {
958 case BGP_EXT_COM_RT_0:
959 /* 2-byte-AS:number fmt */
960 snprintf(output, sizeof(output), "route-target: %u:%u/%d (%s)",
961 EXTRACT_BE_U_2(pptr+2),
962 EXTRACT_BE_U_4(pptr+4),
963 plen, rtc_prefix_in_hex);
964 break;
965
966 case BGP_EXT_COM_RT_1:
967 /* IP-address:AS fmt */
968 snprintf(output, sizeof(output), "route-target: %u.%u.%u.%u:%u/%d (%s)",
969 *(pptr+2), *(pptr+3), *(pptr+4), *(pptr+5),
970 EXTRACT_BE_U_2(pptr+6), plen, rtc_prefix_in_hex);
971 break;
972
973 case BGP_EXT_COM_RT_2:
974 /* 4-byte-AS:number fmt */
975 snprintf(output, sizeof(output), "route-target: %s:%u/%d (%s)",
976 as_printf(ndo, astostr, sizeof(astostr), EXTRACT_BE_U_4(pptr+2)),
977 EXTRACT_BE_U_2(pptr+6), plen, rtc_prefix_in_hex);
978 break;
979
980 default:
981 snprintf(output, sizeof(output), "route target: unknown-type(%04x) (%s/%d)",
982 ec_type,
983 rtc_prefix_in_hex, plen);
984 break;
985 }
986 return (output);
987 }
988
989 /* RFC 4684 */
990 static int
991 decode_rt_routing_info(netdissect_options *ndo,
992 const u_char *pptr)
993 {
994 uint8_t route_target[8];
995 u_int plen;
996 char asbuf[sizeof(astostr)]; /* bgp_vpn_rd_print() overwrites astostr */
997 u_int num_octets;
998
999 /* NLRI "prefix length" from RFC 2858 Section 4. */
1000 plen = GET_U_1(pptr); /* get prefix length */
1001
1002 /* NLRI "prefix" (ibid), valid lengths are { 0, 32, 33, ..., 96 } bits.
1003 * RFC 4684 Section 4 defines the layout of "origin AS" and "route
1004 * target" fields inside the "prefix" depending on its length.
1005 */
1006 if (0 == plen) {
1007 /* Without "origin AS", without "route target". */
1008 ND_PRINT("\n\t default route target");
1009 return 1;
1010 }
1011
1012 if (32 > plen) {
1013 ND_PRINT("\n\t (illegal prefix length)");
1014 return -1;
1015 }
1016
1017 /* With at least "origin AS", possibly with "route target". */
1018 as_printf(ndo, asbuf, sizeof(asbuf), GET_BE_U_4(pptr + 1));
1019
1020 plen -= 32; /* adjust prefix length */
1021
1022 if (64 < plen) {
1023 ND_PRINT("\n\t (illegal prefix length)");
1024 return -1;
1025 }
1026
1027 /* From now on (plen + 7) / 8 evaluates to { 0, 1, 2, ..., 8 }
1028 * and gives the number of octets in the variable-length "route
1029 * target" field inside this NLRI "prefix". Look for it.
1030 */
1031 memset(&route_target, 0, sizeof(route_target));
1032 num_octets = (plen + 7) / 8;
1033 ND_TCHECK_LEN(pptr + 5, num_octets);
1034 memcpy(&route_target, pptr + 5, num_octets);
1035 /* If mask-len is not on octet boundary, ensure all extra bits are 0 */
1036 if (plen % 8) {
1037 ((u_char *)&route_target)[num_octets - 1] &=
1038 ((0xff00 >> (plen % 8)) & 0xff);
1039 }
1040 ND_PRINT("\n\t origin AS: %s, %s",
1041 asbuf,
1042 bgp_rt_prefix_print(ndo, (u_char *)&route_target, plen));
1043
1044 return 5 + num_octets;
1045 trunc:
1046 return -2;
1047 }
1048
1049 static int
1050 decode_labeled_vpn_prefix4(netdissect_options *ndo,
1051 const u_char *pptr, char *buf, size_t buflen)
1052 {
1053 nd_ipv4 addr;
1054 u_int plen;
1055
1056 plen = GET_U_1(pptr); /* get prefix length */
1057
1058 if ((24+64) > plen)
1059 return -1;
1060
1061 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1062
1063 if (32 < plen)
1064 return -1;
1065
1066 memset(&addr, 0, sizeof(addr));
1067 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1068 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1069 if (plen % 8) {
1070 ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
1071 ((0xff00 >> (plen % 8)) & 0xff);
1072 }
1073 /* the label may get offsetted by 4 bits so lets shift it right */
1074 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1075 bgp_vpn_rd_print(ndo, pptr+4),
1076 ipaddr_string(ndo, (const u_char *)&addr),
1077 plen,
1078 GET_BE_U_3(pptr + 1)>>4,
1079 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1080
1081 return 12 + (plen + 7) / 8;
1082
1083 trunc:
1084 return -2;
1085 }
1086
1087 /*
1088 * +-------------------------------+
1089 * | |
1090 * | RD:IPv4-address (12 octets) |
1091 * | |
1092 * +-------------------------------+
1093 * | MDT Group-address (4 octets) |
1094 * +-------------------------------+
1095 */
1096
1097 #define MDT_VPN_NLRI_LEN 16
1098
1099 static int
1100 decode_mdt_vpn_nlri(netdissect_options *ndo,
1101 const u_char *pptr, char *buf, size_t buflen)
1102 {
1103 const u_char *rd;
1104 const u_char *vpn_ip;
1105
1106 /* if the NLRI is not predefined length, quit.*/
1107 if (GET_U_1(pptr) != MDT_VPN_NLRI_LEN * 8)
1108 return -1;
1109 pptr++;
1110
1111 /* RD */
1112 ND_TCHECK_8(pptr);
1113 rd = pptr;
1114 pptr += 8;
1115
1116 /* IPv4 address */
1117 vpn_ip = pptr;
1118 pptr += sizeof(nd_ipv4);
1119
1120 /* MDT Group Address */
1121 snprintf(buf, buflen, "RD: %s, VPN IP Address: %s, MC Group Address: %s",
1122 bgp_vpn_rd_print(ndo, rd), GET_IPADDR_STRING(vpn_ip), GET_IPADDR_STRING(pptr));
1123
1124 return MDT_VPN_NLRI_LEN + 1;
1125
1126 trunc:
1127 return -2;
1128 }
1129
1130 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI 1
1131 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI 2
1132 #define BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI 3
1133 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF 4
1134 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE 5
1135 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN 6
1136 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN 7
1137
1138 static const struct tok bgp_multicast_vpn_route_type_values[] = {
1139 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI, "Intra-AS I-PMSI"},
1140 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI, "Inter-AS I-PMSI"},
1141 { BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI, "S-PMSI"},
1142 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF, "Intra-AS Segment-Leaf"},
1143 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE, "Source-Active"},
1144 { BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN, "Shared Tree Join"},
1145 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN, "Source Tree Join"},
1146 { 0, NULL}
1147 };
1148
1149 static int
1150 decode_multicast_vpn(netdissect_options *ndo,
1151 const u_char *pptr, char *buf, size_t buflen)
1152 {
1153 uint8_t route_type, route_length;
1154 u_int addr_length, sg_length;
1155 u_int offset;
1156
1157 route_type = GET_U_1(pptr);
1158 pptr++;
1159 route_length = GET_U_1(pptr);
1160 pptr++;
1161
1162 snprintf(buf, buflen, "Route-Type: %s (%u), length: %u",
1163 tok2str(bgp_multicast_vpn_route_type_values,
1164 "Unknown", route_type),
1165 route_type, route_length);
1166
1167 switch(route_type) {
1168 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI:
1169 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1170 offset = (u_int)strlen(buf);
1171 snprintf(buf + offset, buflen - offset, ", RD: %s, Originator %s",
1172 bgp_vpn_rd_print(ndo, pptr),
1173 bgp_vpn_ip_print(ndo, pptr + BGP_VPN_RD_LEN,
1174 (route_length - BGP_VPN_RD_LEN) << 3));
1175 break;
1176 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI:
1177 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1178 offset = (u_int)strlen(buf);
1179 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1180 bgp_vpn_rd_print(ndo, pptr),
1181 as_printf(ndo, astostr, sizeof(astostr),
1182 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1183 break;
1184
1185 case BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI:
1186 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1187 offset = (u_int)strlen(buf);
1188 snprintf(buf + offset, buflen - offset, ", RD: %s",
1189 bgp_vpn_rd_print(ndo, pptr));
1190 pptr += BGP_VPN_RD_LEN;
1191
1192 sg_length = bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1193 addr_length = route_length - sg_length;
1194
1195 ND_TCHECK_LEN(pptr, addr_length);
1196 offset = (u_int)strlen(buf);
1197 snprintf(buf + offset, buflen - offset, ", Originator %s",
1198 bgp_vpn_ip_print(ndo, pptr, addr_length << 3));
1199 break;
1200
1201 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE:
1202 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1203 offset = (u_int)strlen(buf);
1204 snprintf(buf + offset, buflen - offset, ", RD: %s",
1205 bgp_vpn_rd_print(ndo, pptr));
1206 pptr += BGP_VPN_RD_LEN;
1207
1208 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1209 break;
1210
1211 case BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN: /* fall through */
1212 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN:
1213 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1214 offset = (u_int)strlen(buf);
1215 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1216 bgp_vpn_rd_print(ndo, pptr),
1217 as_printf(ndo, astostr, sizeof(astostr),
1218 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1219 pptr += BGP_VPN_RD_LEN + 4;
1220
1221 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1222 break;
1223
1224 /*
1225 * no per route-type printing yet.
1226 */
1227 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF:
1228 default:
1229 break;
1230 }
1231
1232 return route_length + 2;
1233
1234 trunc:
1235 return -2;
1236 }
1237
1238 /*
1239 * As I remember, some versions of systems have an snprintf() that
1240 * returns -1 if the buffer would have overflowed. If the return
1241 * value is negative, set buflen to 0, to indicate that we've filled
1242 * the buffer up.
1243 *
1244 * If the return value is greater than buflen, that means that
1245 * the buffer would have overflowed; again, set buflen to 0 in
1246 * that case.
1247 */
1248 #define UPDATE_BUF_BUFLEN(buf, buflen, stringlen) \
1249 if (stringlen<0) \
1250 buflen=0; \
1251 else if ((u_int)stringlen>buflen) \
1252 buflen=0; \
1253 else { \
1254 buflen-=stringlen; \
1255 buf+=stringlen; \
1256 }
1257
1258 static int
1259 decode_labeled_vpn_l2(netdissect_options *ndo,
1260 const u_char *pptr, char *buf, size_t buflen)
1261 {
1262 u_int plen, tlen, tlv_type, tlv_len, ttlv_len;
1263 int stringlen;
1264
1265 plen = GET_BE_U_2(pptr);
1266 tlen = plen;
1267 pptr += 2;
1268 /* Old and new L2VPN NLRI share AFI/SAFI
1269 * -> Assume a 12 Byte-length NLRI is auto-discovery-only
1270 * and > 17 as old format. Complain for the middle case
1271 */
1272 if (plen == 12) {
1273 /* assume AD-only with RD, BGPNH */
1274 ND_TCHECK_LEN(pptr, 12);
1275 buf[0] = '\0';
1276 stringlen = snprintf(buf, buflen, "RD: %s, BGPNH: %s",
1277 bgp_vpn_rd_print(ndo, pptr),
1278 GET_IPADDR_STRING(pptr+8));
1279 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1280 pptr += 12;
1281 tlen -= 12;
1282 return plen + 2;
1283 } else if (plen > 17) {
1284 /* assume old format */
1285 /* RD, ID, LBLKOFF, LBLBASE */
1286
1287 ND_TCHECK_LEN(pptr, 15);
1288 buf[0] = '\0';
1289 stringlen = snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u",
1290 bgp_vpn_rd_print(ndo, pptr),
1291 GET_BE_U_2(pptr + 8),
1292 GET_BE_U_2(pptr + 10),
1293 GET_BE_U_3(pptr + 12)>>4); /* the label is offsetted by 4 bits so lets shift it right */
1294 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1295 pptr += 15;
1296 tlen -= 15;
1297
1298 /* ok now the variable part - lets read out TLVs*/
1299 while (tlen != 0) {
1300 if (tlen < 3) {
1301 if (buflen != 0) {
1302 stringlen=snprintf(buf,buflen, "\n\t\tran past the end");
1303 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1304 }
1305 return plen + 2;
1306 }
1307 tlv_type = GET_U_1(pptr);
1308 pptr++;
1309 tlv_len = GET_BE_U_2(pptr); /* length, in *bits* */
1310 ttlv_len = (tlv_len + 7)/8; /* length, in *bytes* */
1311 pptr += 2;
1312
1313 switch(tlv_type) {
1314 case 1:
1315 if (buflen != 0) {
1316 stringlen=snprintf(buf,buflen, "\n\t\tcircuit status vector (%u) length: %u: 0x",
1317 tlv_type,
1318 tlv_len);
1319 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1320 }
1321 while (ttlv_len != 0) {
1322 if (tlen < 1) {
1323 if (buflen != 0) {
1324 stringlen=snprintf(buf,buflen, " (ran past the end)");
1325 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1326 }
1327 return plen + 2;
1328 }
1329 ND_TCHECK_1(pptr);
1330 if (buflen != 0) {
1331 stringlen=snprintf(buf,buflen, "%02x",
1332 GET_U_1(pptr));
1333 pptr++;
1334 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1335 }
1336 ttlv_len--;
1337 tlen--;
1338 }
1339 break;
1340 default:
1341 if (buflen != 0) {
1342 stringlen=snprintf(buf,buflen, "\n\t\tunknown TLV #%u, length: %u",
1343 tlv_type,
1344 tlv_len);
1345 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1346 }
1347 if (tlen < ttlv_len) {
1348 if (buflen != 0) {
1349 stringlen=snprintf(buf,buflen, " (ran past the end)");
1350 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1351 }
1352 return plen + 2;
1353 }
1354 tlen -= ttlv_len;
1355 break;
1356 }
1357 }
1358 return plen + 2;
1359 } else {
1360 /* complain bitterly ? */
1361 /* fall through */
1362 goto trunc;
1363 }
1364
1365 trunc:
1366 return -2;
1367 }
1368
1369 int
1370 decode_prefix6(netdissect_options *ndo,
1371 const u_char *pd, u_int itemlen, char *buf, size_t buflen)
1372 {
1373 nd_ipv6 addr;
1374 u_int plen, plenbytes;
1375
1376 ITEMCHECK(1);
1377 plen = GET_U_1(pd);
1378 if (128 < plen)
1379 return -1;
1380 itemlen -= 1;
1381
1382 memset(&addr, 0, sizeof(addr));
1383 plenbytes = (plen + 7) / 8;
1384 ND_TCHECK_LEN(pd + 1, plenbytes);
1385 ITEMCHECK(plenbytes);
1386 memcpy(&addr, pd + 1, plenbytes);
1387 if (plen % 8) {
1388 addr[plenbytes - 1] &=
1389 ((0xff00 >> (plen % 8)) & 0xff);
1390 }
1391 snprintf(buf, buflen, "%s/%u", ip6addr_string(ndo, (const u_char *)&addr), plen);
1392 return 1 + plenbytes;
1393
1394 trunc:
1395 return -2;
1396
1397 badtlv:
1398 return -3;
1399 }
1400
1401 static int
1402 decode_labeled_prefix6(netdissect_options *ndo,
1403 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
1404 {
1405 nd_ipv6 addr;
1406 u_int plen, plenbytes;
1407
1408 /* prefix length and label = 4 bytes */
1409 ND_TCHECK_4(pptr);
1410 ITEMCHECK(4);
1411 plen = GET_U_1(pptr); /* get prefix length */
1412
1413 if (24 > plen)
1414 return -1;
1415
1416 plen -= 24; /* adjust prefixlen - labellength */
1417
1418 if (128 < plen)
1419 return -1;
1420 itemlen -= 4;
1421
1422 memset(&addr, 0, sizeof(addr));
1423 plenbytes = (plen + 7) / 8;
1424 ND_TCHECK_LEN(pptr + 4, plenbytes);
1425 memcpy(&addr, pptr + 4, plenbytes);
1426 if (plen % 8) {
1427 addr[plenbytes - 1] &=
1428 ((0xff00 >> (plen % 8)) & 0xff);
1429 }
1430 /* the label may get offsetted by 4 bits so lets shift it right */
1431 snprintf(buf, buflen, "%s/%u, label:%u %s",
1432 ip6addr_string(ndo, (const u_char *)&addr),
1433 plen,
1434 GET_BE_U_3(pptr + 1)>>4,
1435 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1436
1437 return 4 + plenbytes;
1438
1439 trunc:
1440 return -2;
1441
1442 badtlv:
1443 return -3;
1444 }
1445
1446 static int
1447 decode_labeled_vpn_prefix6(netdissect_options *ndo,
1448 const u_char *pptr, char *buf, size_t buflen)
1449 {
1450 nd_ipv6 addr;
1451 u_int plen;
1452
1453 plen = GET_U_1(pptr); /* get prefix length */
1454
1455 if ((24+64) > plen)
1456 return -1;
1457
1458 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1459
1460 if (128 < plen)
1461 return -1;
1462
1463 memset(&addr, 0, sizeof(addr));
1464 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1465 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1466 if (plen % 8) {
1467 addr[(plen + 7) / 8 - 1] &=
1468 ((0xff00 >> (plen % 8)) & 0xff);
1469 }
1470 /* the label may get offsetted by 4 bits so lets shift it right */
1471 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1472 bgp_vpn_rd_print(ndo, pptr+4),
1473 ip6addr_string(ndo, (const u_char *)&addr),
1474 plen,
1475 GET_BE_U_3(pptr + 1)>>4,
1476 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1477
1478 return 12 + (plen + 7) / 8;
1479
1480 trunc:
1481 return -2;
1482 }
1483
1484 static int
1485 decode_clnp_prefix(netdissect_options *ndo,
1486 const u_char *pptr, char *buf, size_t buflen)
1487 {
1488 uint8_t addr[19];
1489 u_int plen;
1490
1491 plen = GET_U_1(pptr); /* get prefix length */
1492
1493 if (152 < plen)
1494 return -1;
1495
1496 memset(&addr, 0, sizeof(addr));
1497 ND_TCHECK_LEN(pptr + 4, (plen + 7) / 8);
1498 memcpy(&addr, pptr + 4, (plen + 7) / 8);
1499 if (plen % 8) {
1500 addr[(plen + 7) / 8 - 1] &=
1501 ((0xff00 >> (plen % 8)) & 0xff);
1502 }
1503 /* Cannot use GET_ISONSAP_STRING (not packet buffer pointer) */
1504 snprintf(buf, buflen, "%s/%u",
1505 isonsap_string(ndo, addr,(plen + 7) / 8),
1506 plen);
1507
1508 return 1 + (plen + 7) / 8;
1509
1510 trunc:
1511 return -2;
1512 }
1513
1514 static int
1515 decode_labeled_vpn_clnp_prefix(netdissect_options *ndo,
1516 const u_char *pptr, char *buf, size_t buflen)
1517 {
1518 uint8_t addr[19];
1519 u_int plen;
1520
1521 plen = GET_U_1(pptr); /* get prefix length */
1522
1523 if ((24+64) > plen)
1524 return -1;
1525
1526 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1527
1528 if (152 < plen)
1529 return -1;
1530
1531 memset(&addr, 0, sizeof(addr));
1532 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1533 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1534 if (plen % 8) {
1535 addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
1536 }
1537 /* the label may get offsetted by 4 bits so lets shift it right */
1538 /* Cannot use GET_ISONSAP_STRING (not packet buffer pointer) */
1539 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1540 bgp_vpn_rd_print(ndo, pptr+4),
1541 isonsap_string(ndo, addr,(plen + 7) / 8),
1542 plen,
1543 GET_BE_U_3(pptr + 1)>>4,
1544 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1545
1546 return 12 + (plen + 7) / 8;
1547
1548 trunc:
1549 return -2;
1550 }
1551
1552 /*
1553 * bgp_attr_get_as_size
1554 *
1555 * Try to find the size of the ASs encoded in an as-path. It is not obvious, as
1556 * both Old speakers that do not support 4 byte AS, and the new speakers that do
1557 * support, exchange AS-Path with the same path-attribute type value 0x02.
1558 */
1559 static u_int
1560 bgp_attr_get_as_size(netdissect_options *ndo,
1561 uint8_t bgpa_type, const u_char *pptr, u_int len)
1562 {
1563 const u_char *tptr = pptr;
1564
1565 /*
1566 * If the path attribute is the optional AS4 path type, then we already
1567 * know, that ASs must be encoded in 4 byte format.
1568 */
1569 if (bgpa_type == BGPTYPE_AS4_PATH) {
1570 return 4;
1571 }
1572
1573 /*
1574 * Let us assume that ASs are of 2 bytes in size, and check if the AS-Path
1575 * TLV is good. If not, ask the caller to try with AS encoded as 4 bytes
1576 * each.
1577 */
1578 while (tptr < pptr + len) {
1579 /*
1580 * If we do not find a valid segment type, our guess might be wrong.
1581 */
1582 if (GET_U_1(tptr) < BGP_AS_SEG_TYPE_MIN || GET_U_1(tptr) > BGP_AS_SEG_TYPE_MAX) {
1583 goto trunc;
1584 }
1585 tptr += 2 + GET_U_1(tptr + 1) * 2;
1586 }
1587
1588 /*
1589 * If we correctly reached end of the AS path attribute data content,
1590 * then most likely ASs were indeed encoded as 2 bytes.
1591 */
1592 if (tptr == pptr + len) {
1593 return 2;
1594 }
1595
1596 trunc:
1597
1598 /*
1599 * We can come here, either we did not have enough data, or if we
1600 * try to decode 4 byte ASs in 2 byte format. Either way, return 4,
1601 * so that calller can try to decode each AS as of 4 bytes. If indeed
1602 * there was not enough data, it will crib and end the parse anyways.
1603 */
1604 return 4;
1605 }
1606
1607 /*
1608 * The only way to know that a BGP UPDATE message is using add path is
1609 * by checking if the capability is in the OPEN message which we may have missed.
1610 * So this function checks if it is possible that the update could contain add path
1611 * and if so it checks that standard BGP doesn't make sense.
1612 */
1613 static int
1614 check_add_path(netdissect_options *ndo, const u_char *pptr, u_int length,
1615 u_int max_prefix_length)
1616 {
1617 u_int offset, prefix_length;
1618
1619 if (length < 5) {
1620 return 0;
1621 }
1622
1623 /*
1624 * Scan through the NLRI information under the assumpetion that
1625 * it doesn't have path IDs.
1626 */
1627 for (offset = 0; offset < length;) {
1628 offset += 4;
1629 if (!ND_TTEST_1(pptr + offset)) {
1630 /* We ran out of captured data; quit scanning. */
1631 break;
1632 }
1633 prefix_length = GET_U_1(pptr + offset);
1634 /*
1635 * Add 4 to cover the path id
1636 * and check the prefix length isn't greater than 32/128.
1637 */
1638 if (prefix_length > max_prefix_length) {
1639 return 0;
1640 }
1641 /* Add 1 for the prefix_length byte and prefix_length to cover the address */
1642 offset += 1 + ((prefix_length + 7) / 8);
1643 }
1644 /* check we haven't gone past the end of the section */
1645 if (offset > length) {
1646 return 0;
1647 }
1648
1649 /* check it's not standard BGP */
1650 for (offset = 0; offset < length; ) {
1651 if (!ND_TTEST_1(pptr + offset)) {
1652 /* We ran out of captured data; quit scanning. */
1653 break;
1654 }
1655 prefix_length = GET_U_1(pptr + offset);
1656 /*
1657 * If the prefix_length is zero (0.0.0.0/0)
1658 * and since it's not the only address (length >= 5)
1659 * then it is add-path
1660 */
1661 if (prefix_length < 1 || prefix_length > max_prefix_length) {
1662 return 1;
1663 }
1664 offset += 1 + ((prefix_length + 7) / 8);
1665 }
1666 if (offset > length) {
1667 return 1;
1668 }
1669
1670 /* assume not add-path by default */
1671 return 0;
1672 }
1673
1674 static int
1675 bgp_mp_af_print(netdissect_options *ndo,
1676 const u_char *tptr, u_int tlen,
1677 uint16_t *afp, uint8_t *safip)
1678 {
1679 uint16_t af;
1680 uint8_t safi;
1681
1682 af = GET_BE_U_2(tptr);
1683 *afp = af;
1684 safi = GET_U_1(tptr + 2);
1685 *safip = safi;
1686
1687 ND_PRINT("\n\t AFI: %s (%u), %sSAFI: %s (%u)",
1688 tok2str(af_values, "Unknown AFI", af),
1689 af,
1690 (safi>128) ? "vendor specific " : "", /* 128 is meanwhile wellknown */
1691 tok2str(bgp_safi_values, "Unknown SAFI", safi),
1692 safi);
1693
1694 switch(af<<8 | safi) {
1695 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1696 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1697 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1698 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1699 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1700 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1701 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1702 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1703 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
1704 case (AFNUM_INET<<8 | SAFNUM_MDT):
1705 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1706 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1707 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1708 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1709 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1710 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1711 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1712 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1713 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1714 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1715 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1716 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1717 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1718 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1719 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1720 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1721 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1722 break;
1723 default:
1724 ND_TCHECK_LEN(tptr, tlen);
1725 ND_PRINT("\n\t no AFI %u / SAFI %u decoder", af, safi);
1726 if (ndo->ndo_vflag <= 1)
1727 print_unknown_data(ndo, tptr, "\n\t ", tlen);
1728 return -1;
1729 }
1730 return 0;
1731 trunc:
1732 return -2;
1733 }
1734
1735 static int
1736 bgp_nlri_print(netdissect_options *ndo, uint16_t af, uint8_t safi,
1737 const u_char *tptr, u_int len,
1738 char *buf, size_t buflen,
1739 int add_path4, int add_path6)
1740 {
1741 int advance;
1742 u_int path_id = 0;
1743
1744 switch (af<<8 | safi) {
1745 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1746 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1747 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1748 if (add_path4) {
1749 path_id = GET_BE_U_4(tptr);
1750 tptr += 4;
1751 }
1752 advance = decode_prefix4(ndo, tptr, len, buf, buflen);
1753 if (advance == -1)
1754 ND_PRINT("\n\t (illegal prefix length)");
1755 else if (advance == -2)
1756 goto trunc;
1757 else if (advance == -3)
1758 break; /* bytes left, but not enough */
1759 else
1760 ND_PRINT("\n\t %s", buf);
1761 if (add_path4) {
1762 ND_PRINT(" Path Id: %u", path_id);
1763 advance += 4;
1764 }
1765 break;
1766 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1767 advance = decode_labeled_prefix4(ndo, tptr, len, buf, buflen);
1768 if (advance == -1)
1769 ND_PRINT("\n\t (illegal prefix length)");
1770 else if (advance == -2)
1771 goto trunc;
1772 else if (advance == -3)
1773 break; /* bytes left, but not enough */
1774 else
1775 ND_PRINT("\n\t %s", buf);
1776 break;
1777 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1778 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1779 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1780 advance = decode_labeled_vpn_prefix4(ndo, tptr, buf, buflen);
1781 if (advance == -1)
1782 ND_PRINT("\n\t (illegal prefix length)");
1783 else if (advance == -2)
1784 goto trunc;
1785 else
1786 ND_PRINT("\n\t %s", buf);
1787 break;
1788 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1789 advance = decode_rt_routing_info(ndo, tptr);
1790 if (advance == -2)
1791 goto trunc;
1792 break;
1793 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN): /* fall through */
1794 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST_VPN):
1795 advance = decode_multicast_vpn(ndo, tptr, buf, buflen);
1796 if (advance == -1)
1797 ND_PRINT("\n\t (illegal prefix length)");
1798 else if (advance == -2)
1799 goto trunc;
1800 else
1801 ND_PRINT("\n\t %s", buf);
1802 break;
1803
1804 case (AFNUM_INET<<8 | SAFNUM_MDT):
1805 advance = decode_mdt_vpn_nlri(ndo, tptr, buf, buflen);
1806 if (advance == -1)
1807 ND_PRINT("\n\t (illegal prefix length)");
1808 else if (advance == -2)
1809 goto trunc;
1810 else
1811 ND_PRINT("\n\t %s", buf);
1812 break;
1813 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1814 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1815 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1816 if (add_path6) {
1817 path_id = GET_BE_U_4(tptr);
1818 tptr += 4;
1819 }
1820 advance = decode_prefix6(ndo, tptr, len, buf, buflen);
1821 if (advance == -1)
1822 ND_PRINT("\n\t (illegal prefix length)");
1823 else if (advance == -2)
1824 goto trunc;
1825 else if (advance == -3)
1826 break; /* bytes left, but not enough */
1827 else
1828 ND_PRINT("\n\t %s", buf);
1829 if (add_path6) {
1830 ND_PRINT(" Path Id: %u", path_id);
1831 advance += 4;
1832 }
1833 break;
1834 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1835 advance = decode_labeled_prefix6(ndo, tptr, len, buf, buflen);
1836 if (advance == -1)
1837 ND_PRINT("\n\t (illegal prefix length)");
1838 else if (advance == -2)
1839 goto trunc;
1840 else if (advance == -3)
1841 break; /* bytes left, but not enough */
1842 else
1843 ND_PRINT("\n\t %s", buf);
1844 break;
1845 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1846 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1847 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1848 advance = decode_labeled_vpn_prefix6(ndo, tptr, buf, buflen);
1849 if (advance == -1)
1850 ND_PRINT("\n\t (illegal prefix length)");
1851 else if (advance == -2)
1852 goto trunc;
1853 else
1854 ND_PRINT("\n\t %s", buf);
1855 break;
1856 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1857 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1858 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1859 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1860 advance = decode_labeled_vpn_l2(ndo, tptr, buf, buflen);
1861 if (advance == -1)
1862 ND_PRINT("\n\t (illegal length)");
1863 else if (advance == -2)
1864 goto trunc;
1865 else
1866 ND_PRINT("\n\t %s", buf);
1867 break;
1868 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1869 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1870 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1871 advance = decode_clnp_prefix(ndo, tptr, buf, buflen);
1872 if (advance == -1)
1873 ND_PRINT("\n\t (illegal prefix length)");
1874 else if (advance == -2)
1875 goto trunc;
1876 else
1877 ND_PRINT("\n\t %s", buf);
1878 break;
1879 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1880 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1881 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1882 advance = decode_labeled_vpn_clnp_prefix(ndo, tptr, buf, buflen);
1883 if (advance == -1)
1884 ND_PRINT("\n\t (illegal prefix length)");
1885 else if (advance == -2)
1886 goto trunc;
1887 else
1888 ND_PRINT("\n\t %s", buf);
1889 break;
1890 default:
1891 /*
1892 * This should not happen, we should have been protected
1893 * by bgp_mp_af_print()'s return value.
1894 */
1895 ND_PRINT("\n\t ERROR: no AFI %u / SAFI %u decoder", af, safi);
1896 advance = -4;
1897 break;
1898 }
1899 return advance;
1900 trunc: /* we rely on the caller to recognize -2 return value */
1901 return -2;
1902 }
1903
1904 static int
1905 bgp_attr_print(netdissect_options *ndo,
1906 uint8_t atype, const u_char *pptr, u_int len,
1907 const unsigned attr_set_level)
1908 {
1909 u_int i;
1910 uint16_t af;
1911 uint8_t safi, snpa, nhlen;
1912 int advance;
1913 u_int tlen;
1914 const u_char *tptr;
1915 char buf[MAXHOSTNAMELEN + 100];
1916 u_int as_size;
1917 int add_path4, add_path6;
1918 int ret;
1919
1920 tptr = pptr;
1921 tlen = len;
1922
1923 switch (atype) {
1924 case BGPTYPE_ORIGIN:
1925 if (len != 1)
1926 ND_PRINT("invalid len");
1927 else {
1928 ND_PRINT("%s", tok2str(bgp_origin_values,
1929 "Unknown Origin Typecode",
1930 GET_U_1(tptr)));
1931 }
1932 break;
1933
1934 /*
1935 * Process AS4 byte path and AS2 byte path attributes here.
1936 */
1937 case BGPTYPE_AS4_PATH:
1938 case BGPTYPE_AS_PATH:
1939 if (len % 2) {
1940 ND_PRINT("invalid len");
1941 break;
1942 }
1943 if (!len) {
1944 ND_PRINT("empty");
1945 break;
1946 }
1947
1948 /*
1949 * BGP updates exchanged between New speakers that support 4
1950 * byte AS, ASs are always encoded in 4 bytes. There is no
1951 * definitive way to find this, just by the packet's
1952 * contents. So, check for packet's TLV's sanity assuming
1953 * 2 bytes first, and it does not pass, assume that ASs are
1954 * encoded in 4 bytes format and move on.
1955 */
1956 as_size = bgp_attr_get_as_size(ndo, atype, pptr, len);
1957
1958 while (tptr < pptr + len) {
1959 ND_PRINT("%s", tok2str(bgp_as_path_segment_open_values,
1960 "?", GET_U_1(tptr)));
1961 for (i = 0; i < GET_U_1(tptr + 1) * as_size; i += as_size) {
1962 ND_TCHECK_LEN(tptr + 2 + i, as_size);
1963 ND_PRINT("%s ",
1964 as_printf(ndo, astostr, sizeof(astostr),
1965 as_size == 2 ?
1966 GET_BE_U_2(tptr + i + 2) :
1967 GET_BE_U_4(tptr + i + 2)));
1968 }
1969 ND_PRINT("%s", tok2str(bgp_as_path_segment_close_values,
1970 "?", GET_U_1(tptr)));
1971 tptr += 2 + GET_U_1(tptr + 1) * as_size;
1972 }
1973 break;
1974 case BGPTYPE_NEXT_HOP:
1975 if (len != 4)
1976 ND_PRINT("invalid len");
1977 else {
1978 ND_PRINT("%s", GET_IPADDR_STRING(tptr));
1979 }
1980 break;
1981 case BGPTYPE_MULTI_EXIT_DISC:
1982 case BGPTYPE_LOCAL_PREF:
1983 if (len != 4)
1984 ND_PRINT("invalid len");
1985 else {
1986 ND_PRINT("%u", GET_BE_U_4(tptr));
1987 }
1988 break;
1989 case BGPTYPE_ATOMIC_AGGREGATE:
1990 if (len != 0)
1991 ND_PRINT("invalid len");
1992 break;
1993 case BGPTYPE_AGGREGATOR:
1994
1995 /*
1996 * Depending on the AS encoded is of 2 bytes or of 4 bytes,
1997 * the length of this PA can be either 6 bytes or 8 bytes.
1998 */
1999 if (len != 6 && len != 8) {
2000 ND_PRINT("invalid len");
2001 break;
2002 }
2003 ND_TCHECK_LEN(tptr, len);
2004 if (len == 6) {
2005 ND_PRINT(" AS #%s, origin %s",
2006 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(tptr)),
2007 GET_IPADDR_STRING(tptr + 2));
2008 } else {
2009 ND_PRINT(" AS #%s, origin %s",
2010 as_printf(ndo, astostr, sizeof(astostr),
2011 GET_BE_U_4(tptr)), GET_IPADDR_STRING(tptr + 4));
2012 }
2013 break;
2014 case BGPTYPE_AGGREGATOR4:
2015 if (len != 8) {
2016 ND_PRINT("invalid len");
2017 break;
2018 }
2019 ND_PRINT(" AS #%s, origin %s",
2020 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)),
2021 GET_IPADDR_STRING(tptr + 4));
2022 break;
2023 case BGPTYPE_COMMUNITIES:
2024 if (len % 4) {
2025 ND_PRINT("invalid len");
2026 break;
2027 }
2028 while (tlen != 0) {
2029 uint32_t comm;
2030 ND_TCHECK_4(tptr);
2031 if (tlen < 4)
2032 goto trunc;
2033 comm = GET_BE_U_4(tptr);
2034 switch (comm) {
2035 case BGP_COMMUNITY_NO_EXPORT:
2036 ND_PRINT(" NO_EXPORT");
2037 break;
2038 case BGP_COMMUNITY_NO_ADVERT:
2039 ND_PRINT(" NO_ADVERTISE");
2040 break;
2041 case BGP_COMMUNITY_NO_EXPORT_SUBCONFED:
2042 ND_PRINT(" NO_EXPORT_SUBCONFED");
2043 break;
2044 default:
2045 ND_PRINT("%u:%u%s",
2046 (comm >> 16) & 0xffff,
2047 comm & 0xffff,
2048 (tlen>4) ? ", " : "");
2049 break;
2050 }
2051 tlen -=4;
2052 tptr +=4;
2053 }
2054 break;
2055 case BGPTYPE_ORIGINATOR_ID:
2056 if (len != 4) {
2057 ND_PRINT("invalid len");
2058 break;
2059 }
2060 ND_PRINT("%s",GET_IPADDR_STRING(tptr));
2061 break;
2062 case BGPTYPE_CLUSTER_LIST:
2063 if (len % 4) {
2064 ND_PRINT("invalid len");
2065 break;
2066 }
2067 while (tlen != 0) {
2068 if (tlen < 4)
2069 goto trunc;
2070 ND_PRINT("%s%s",
2071 GET_IPADDR_STRING(tptr),
2072 (tlen>4) ? ", " : "");
2073 tlen -=4;
2074 tptr +=4;
2075 }
2076 break;
2077 case BGPTYPE_MP_REACH_NLRI:
2078 ND_TCHECK_3(tptr);
2079 if (tlen < 3)
2080 goto trunc;
2081 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2082 if (ret == -2)
2083 goto trunc;
2084 if (ret < 0)
2085 break;
2086
2087 tptr += 3;
2088 tlen -= 3;
2089
2090 ND_TCHECK_1(tptr);
2091 if (tlen < 1)
2092 goto trunc;
2093 nhlen = GET_U_1(tptr);
2094 tptr++;
2095 tlen--;
2096
2097 if (nhlen) {
2098 u_int nnh = 0;
2099 uint8_t tnhlen = nhlen;
2100 if (tlen < tnhlen)
2101 goto trunc;
2102 ND_PRINT("\n\t nexthop: ");
2103 while (tnhlen != 0) {
2104 if (nnh++ > 0) {
2105 ND_PRINT(", " );
2106 }
2107 switch(af<<8 | safi) {
2108 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
2109 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
2110 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
2111 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
2112 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
2113 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
2114 case (AFNUM_INET<<8 | SAFNUM_MDT):
2115 if (tnhlen < sizeof(nd_ipv4)) {
2116 ND_PRINT("invalid len");
2117 tptr += tnhlen;
2118 tlen -= tnhlen;
2119 tnhlen = 0;
2120 } else {
2121 ND_PRINT("%s",GET_IPADDR_STRING(tptr));
2122 tptr += sizeof(nd_ipv4);
2123 tnhlen -= sizeof(nd_ipv4);
2124 tlen -= sizeof(nd_ipv4);
2125 }
2126 break;
2127 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
2128 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
2129 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
2130 if (tnhlen < sizeof(nd_ipv4)+BGP_VPN_RD_LEN) {
2131 ND_PRINT("invalid len");
2132 tptr += tnhlen;
2133 tlen -= tnhlen;
2134 tnhlen = 0;
2135 } else {
2136 ND_PRINT("RD: %s, %s",
2137 bgp_vpn_rd_print(ndo, tptr),
2138 GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN));
2139 tptr += (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2140 tlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2141 tnhlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2142 }
2143 break;
2144 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
2145 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
2146 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
2147 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
2148 if (tnhlen < sizeof(nd_ipv6)) {
2149 ND_PRINT("invalid len");
2150 tptr += tnhlen;
2151 tlen -= tnhlen;
2152 tnhlen = 0;
2153 } else {
2154 ND_PRINT("%s", GET_IP6ADDR_STRING(tptr));
2155 tptr += sizeof(nd_ipv6);
2156 tlen -= sizeof(nd_ipv6);
2157 tnhlen -= sizeof(nd_ipv6);
2158 }
2159 break;
2160 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
2161 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
2162 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
2163 if (tnhlen < sizeof(nd_ipv6)+BGP_VPN_RD_LEN) {
2164 ND_PRINT("invalid len");
2165 tptr += tnhlen;
2166 tlen -= tnhlen;
2167 tnhlen = 0;
2168 } else {
2169 ND_PRINT("RD: %s, %s",
2170 bgp_vpn_rd_print(ndo, tptr),
2171 GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN));
2172 tptr += (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2173 tlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2174 tnhlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2175 }
2176 break;
2177 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
2178 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
2179 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
2180 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
2181 if (tnhlen < sizeof(nd_ipv4)) {
2182 ND_PRINT("invalid len");
2183 tptr += tnhlen;
2184 tlen -= tnhlen;
2185 tnhlen = 0;
2186 } else {
2187 ND_PRINT("%s", GET_IPADDR_STRING(tptr));
2188 tptr += (sizeof(nd_ipv4));
2189 tlen -= (sizeof(nd_ipv4));
2190 tnhlen -= (sizeof(nd_ipv4));
2191 }
2192 break;
2193 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
2194 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
2195 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
2196 ND_PRINT("%s", GET_ISONSAP_STRING(tptr, tnhlen));
2197 tptr += tnhlen;
2198 tlen -= tnhlen;
2199 tnhlen = 0;
2200 break;
2201
2202 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
2203 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
2204 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
2205 if (tnhlen < BGP_VPN_RD_LEN+1) {
2206 ND_PRINT("invalid len");
2207 tptr += tnhlen;
2208 tlen -= tnhlen;
2209 tnhlen = 0;
2210 } else {
2211 ND_TCHECK_LEN(tptr, tnhlen);
2212 ND_PRINT("RD: %s, %s",
2213 bgp_vpn_rd_print(ndo, tptr),
2214 GET_ISONSAP_STRING(tptr+BGP_VPN_RD_LEN,tnhlen-BGP_VPN_RD_LEN));
2215 /* rfc986 mapped IPv4 address ? */
2216 if (GET_BE_U_4(tptr + BGP_VPN_RD_LEN) == 0x47000601)
2217 ND_PRINT(" = %s", GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN+4));
2218 /* rfc1888 mapped IPv6 address ? */
2219 else if (GET_BE_U_3(tptr + BGP_VPN_RD_LEN) == 0x350000)
2220 ND_PRINT(" = %s", GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN+3));
2221 tptr += tnhlen;
2222 tlen -= tnhlen;
2223 tnhlen = 0;
2224 }
2225 break;
2226 default:
2227 /*
2228 * bgp_mp_af_print() should have saved us from
2229 * an unsupported AFI/SAFI.
2230 */
2231 ND_PRINT("ERROR: no AFI %u/SAFI %u nexthop decoder", af, safi);
2232 tptr += tnhlen;
2233 tlen -= tnhlen;
2234 tnhlen = 0;
2235 goto done;
2236 break;
2237 }
2238 }
2239 }
2240 ND_PRINT(", nh-length: %u", nhlen);
2241
2242 /* As per RFC 2858; this is reserved in RFC 4760 */
2243 if (tlen < 1)
2244 goto trunc;
2245 snpa = GET_U_1(tptr);
2246 tptr++;
2247 tlen--;
2248
2249 if (snpa) {
2250 ND_PRINT("\n\t %u SNPA", snpa);
2251 for (/*nothing*/; snpa != 0; snpa--) {
2252 uint8_t snpalen;
2253 if (tlen < 1)
2254 goto trunc;
2255 snpalen = GET_U_1(tptr);
2256 ND_PRINT("\n\t %u bytes", snpalen);
2257 tptr++;
2258 tlen--;
2259 if (tlen < snpalen)
2260 goto trunc;
2261 ND_TCHECK_LEN(tptr, snpalen);
2262 tptr += snpalen;
2263 tlen -= snpalen;
2264 }
2265 } else {
2266 ND_PRINT(", no SNPA");
2267 }
2268
2269 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2270 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2271
2272 while (tptr < pptr + len) {
2273 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2274 add_path4, add_path6);
2275 if (advance == -2)
2276 goto trunc;
2277 if (advance < 0)
2278 break;
2279 tptr += advance;
2280 }
2281 break;
2282
2283 case BGPTYPE_MP_UNREACH_NLRI:
2284 ND_TCHECK_LEN(tptr, BGP_MP_NLRI_MINSIZE);
2285 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2286 if (ret == -2)
2287 goto trunc;
2288 if (ret < 0)
2289 break;
2290
2291 if (len == BGP_MP_NLRI_MINSIZE)
2292 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2293
2294 tptr += 3;
2295
2296 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2297 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2298
2299 while (tptr < pptr + len) {
2300 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2301 add_path4, add_path6);
2302 if (advance == -2)
2303 goto trunc;
2304 if (advance < 0)
2305 break;
2306 tptr += advance;
2307 }
2308 break;
2309 case BGPTYPE_EXTD_COMMUNITIES:
2310 if (len % 8) {
2311 ND_PRINT("invalid len");
2312 break;
2313 }
2314 while (tlen != 0) {
2315 uint16_t extd_comm;
2316
2317 ND_TCHECK_2(tptr);
2318 if (tlen < 2)
2319 goto trunc;
2320 extd_comm=GET_BE_U_2(tptr);
2321
2322 ND_PRINT("\n\t %s (0x%04x), Flags [%s]",
2323 tok2str(bgp_extd_comm_subtype_values,
2324 "unknown extd community typecode",
2325 extd_comm),
2326 extd_comm,
2327 bittok2str(bgp_extd_comm_flag_values, "none", extd_comm));
2328
2329 ND_TCHECK_8(tptr);
2330 if (tlen < 8)
2331 goto trunc;
2332 ND_PRINT(": ");
2333 bgp_extended_community_print(ndo, tptr);
2334 tlen -= 8;
2335 tptr += 8;
2336 }
2337 break;
2338
2339 case BGPTYPE_PMSI_TUNNEL:
2340 {
2341 uint8_t tunnel_type, flags;
2342
2343 ND_TCHECK_5(tptr);
2344 if (tlen < 5)
2345 goto trunc;
2346 flags = GET_U_1(tptr);
2347 tunnel_type = GET_U_1(tptr + 1);
2348
2349 ND_PRINT("\n\t Tunnel-type %s (%u), Flags [%s], MPLS Label %u",
2350 tok2str(bgp_pmsi_tunnel_values, "Unknown", tunnel_type),
2351 tunnel_type,
2352 bittok2str(bgp_pmsi_flag_values, "none", flags),
2353 GET_BE_U_3(tptr + 2)>>4);
2354
2355 tptr +=5;
2356 tlen -= 5;
2357
2358 switch (tunnel_type) {
2359 case BGP_PMSI_TUNNEL_PIM_SM: /* fall through */
2360 case BGP_PMSI_TUNNEL_PIM_BIDIR:
2361 ND_PRINT("\n\t Sender %s, P-Group %s",
2362 GET_IPADDR_STRING(tptr),
2363 GET_IPADDR_STRING(tptr+4));
2364 break;
2365
2366 case BGP_PMSI_TUNNEL_PIM_SSM:
2367 ND_PRINT("\n\t Root-Node %s, P-Group %s",
2368 GET_IPADDR_STRING(tptr),
2369 GET_IPADDR_STRING(tptr+4));
2370 break;
2371 case BGP_PMSI_TUNNEL_INGRESS:
2372 ND_PRINT("\n\t Tunnel-Endpoint %s",
2373 GET_IPADDR_STRING(tptr));
2374 break;
2375 case BGP_PMSI_TUNNEL_LDP_P2MP: /* fall through */
2376 case BGP_PMSI_TUNNEL_LDP_MP2MP:
2377 ND_PRINT("\n\t Root-Node %s, LSP-ID 0x%08x",
2378 GET_IPADDR_STRING(tptr),
2379 GET_BE_U_4(tptr + 4));
2380 break;
2381 case BGP_PMSI_TUNNEL_RSVP_P2MP:
2382 ND_PRINT("\n\t Extended-Tunnel-ID %s, P2MP-ID 0x%08x",
2383 GET_IPADDR_STRING(tptr),
2384 GET_BE_U_4(tptr + 4));
2385 break;
2386 default:
2387 if (ndo->ndo_vflag <= 1) {
2388 print_unknown_data(ndo, tptr, "\n\t ", tlen);
2389 }
2390 }
2391 break;
2392 }
2393 case BGPTYPE_AIGP:
2394 {
2395 uint8_t type;
2396 uint16_t length;
2397
2398 while (tlen >= 3) {
2399 type = GET_U_1(tptr);
2400 length = GET_BE_U_2(tptr + 1);
2401 tptr += 3;
2402 tlen -= 3;
2403
2404 ND_PRINT("\n\t %s TLV (%u), length %u",
2405 tok2str(bgp_aigp_values, "Unknown", type),
2406 type, length);
2407
2408 if (length < 3)
2409 goto trunc;
2410 length -= 3;
2411
2412 /*
2413 * Check if we can read the TLV data.
2414 */
2415 ND_TCHECK_LEN(tptr + 3, length);
2416 if (tlen < length)
2417 goto trunc;
2418
2419 switch (type) {
2420
2421 case BGP_AIGP_TLV:
2422 if (length < 8)
2423 goto trunc;
2424 ND_PRINT(", metric %" PRIu64,
2425 GET_BE_U_8(tptr));
2426 break;
2427
2428 default:
2429 if (ndo->ndo_vflag <= 1) {
2430 print_unknown_data(ndo, tptr,"\n\t ", length);
2431 }
2432 }
2433
2434 tptr += length;
2435 tlen -= length;
2436 }
2437 break;
2438 }
2439 case BGPTYPE_ATTR_SET:
2440 ND_TCHECK_4(tptr);
2441 if (len < 4)
2442 goto trunc;
2443 ND_PRINT("\n\t Origin AS: %s",
2444 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)));
2445 tptr += 4;
2446 len -= 4;
2447
2448 while (len) {
2449 u_int aflags, alenlen, alen;
2450
2451 ND_TCHECK_2(tptr);
2452 if (len < 2) {
2453 ND_PRINT(" [path attr too short]");
2454 tptr += len;
2455 break;
2456 }
2457 aflags = GET_U_1(tptr);
2458 atype = GET_U_1(tptr + 1);
2459 tptr += 2;
2460 len -= 2;
2461 alenlen = bgp_attr_lenlen(aflags, tptr);
2462 ND_TCHECK_LEN(tptr, alenlen);
2463 if (len < alenlen) {
2464 ND_PRINT(" [path attr too short]");
2465 tptr += len;
2466 break;
2467 }
2468 alen = bgp_attr_len(aflags, tptr);
2469 tptr += alenlen;
2470 len -= alenlen;
2471
2472 ND_PRINT("\n\t %s (%u), length: %u",
2473 tok2str(bgp_attr_values,
2474 "Unknown Attribute", atype),
2475 atype,
2476 alen);
2477
2478 if (aflags) {
2479 ND_PRINT(", Flags [%s%s%s%s",
2480 aflags & 0x80 ? "O" : "",
2481 aflags & 0x40 ? "T" : "",
2482 aflags & 0x20 ? "P" : "",
2483 aflags & 0x10 ? "E" : "");
2484 if (aflags & 0xf)
2485 ND_PRINT("+%x", aflags & 0xf);
2486 ND_PRINT("]");
2487 }
2488 ND_PRINT(": ");
2489 if (len < alen) {
2490 ND_PRINT(" [path attr too short]");
2491 tptr += len;
2492 break;
2493 }
2494 /*
2495 * The protocol encoding per se allows ATTR_SET to be nested
2496 * as many times as the message can accommodate. This printer
2497 * used to be able to recurse into ATTR_SET contents until the
2498 * stack exhaustion, but now there is a limit on that (if live
2499 * protocol exchange goes that many levels deep, something is
2500 * probably wrong anyway). Feel free to refine this value if
2501 * you can find the spec with respective normative text.
2502 */
2503 if (attr_set_level == 10)
2504 ND_PRINT("(too many nested levels, not recursing)");
2505 else if (!bgp_attr_print(ndo, atype, tptr, alen, attr_set_level + 1))
2506 return 0;
2507 tptr += alen;
2508 len -= alen;
2509 }
2510 break;
2511
2512 case BGPTYPE_LARGE_COMMUNITY:
2513 if (len == 0 || len % 12) {
2514 ND_PRINT("invalid len");
2515 break;
2516 }
2517 ND_PRINT("\n\t ");
2518 while (len != 0) {
2519 ND_PRINT("%u:%u:%u%s",
2520 GET_BE_U_4(tptr),
2521 GET_BE_U_4(tptr + 4),
2522 GET_BE_U_4(tptr + 8),
2523 (len > 12) ? ", " : "");
2524 tptr += 12;
2525 /*
2526 * len will always be a multiple of 12, as per the above,
2527 * so this will never underflow.
2528 */
2529 len -= 12;
2530 }
2531 break;
2532 default:
2533 ND_TCHECK_LEN(pptr, len);
2534 ND_PRINT("\n\t no Attribute %u decoder", atype); /* we have no decoder for the attribute */
2535 if (ndo->ndo_vflag <= 1)
2536 print_unknown_data(ndo, pptr, "\n\t ", len);
2537 break;
2538 }
2539 done:
2540 if (ndo->ndo_vflag > 1 && len) { /* omit zero length attributes*/
2541 ND_TCHECK_LEN(pptr, len);
2542 print_unknown_data(ndo, pptr, "\n\t ", len);
2543 }
2544 return 1;
2545
2546 trunc:
2547 return 0;
2548 }
2549
2550 static void
2551 bgp_capabilities_print(netdissect_options *ndo,
2552 const u_char *opt, u_int caps_len)
2553 {
2554 u_int cap_type, cap_len, tcap_len, cap_offset;
2555 u_int i = 0;
2556
2557 while (i < caps_len) {
2558 ND_TCHECK_LEN(opt + i, BGP_CAP_HEADER_SIZE);
2559 cap_type=GET_U_1(opt + i);
2560 cap_len=GET_U_1(opt + i + 1);
2561 ND_PRINT("\n\t %s (%u), length: %u",
2562 tok2str(bgp_capcode_values, "Unknown", cap_type),
2563 cap_type,
2564 cap_len);
2565 ND_TCHECK_LEN(opt + 2 + i, cap_len);
2566 switch (cap_type) {
2567 case BGP_CAPCODE_MP:
2568 /* AFI (16 bits), Reserved (8 bits), SAFI (8 bits) */
2569 if (cap_len < 4) {
2570 ND_PRINT(" (too short, < 4)");
2571 return;
2572 }
2573 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u)",
2574 tok2str(af_values, "Unknown", GET_BE_U_2(opt + i + 2)),
2575 GET_BE_U_2(opt + i + 2),
2576 tok2str(bgp_safi_values, "Unknown", GET_U_1(opt + i + 5)),
2577 GET_U_1(opt + i + 5));
2578 break;
2579 case BGP_CAPCODE_ML:
2580 cap_offset = 2;
2581 tcap_len = cap_len;
2582 while (tcap_len >= 4) {
2583 ND_PRINT( "\n\t\tAFI %s (%u), SAFI %s (%u), Count: %u",
2584 tok2str(af_values, "Unknown",
2585 GET_BE_U_2(opt + i + cap_offset)),
2586 GET_BE_U_2(opt + i + cap_offset),
2587 tok2str(bgp_safi_values, "Unknown",
2588 GET_U_1(opt + i + cap_offset + 2)),
2589 GET_U_1(opt + i + cap_offset + 2),
2590 GET_U_1(opt + i + cap_offset + 3));
2591 tcap_len -= 4;
2592 cap_offset += 4;
2593 }
2594 break;
2595 case BGP_CAPCODE_RESTART:
2596 /* Restart Flags (4 bits), Restart Time in seconds (12 bits) */
2597 if (cap_len < 2) {
2598 ND_PRINT(" (too short, < 2)");
2599 return;
2600 }
2601 tcap_len=cap_len;
2602 ND_PRINT("\n\t\tRestart Flags: [%s], Restart Time %us",
2603 ((GET_U_1(opt + i + 2))&0x80) ? "R" : "none",
2604 GET_BE_U_2(opt + i + 2)&0xfff);
2605 tcap_len-=2;
2606 cap_offset=4;
2607 while(tcap_len>=4) {
2608 ND_PRINT("\n\t\t AFI %s (%u), SAFI %s (%u), Forwarding state preserved: %s",
2609 tok2str(af_values,"Unknown",
2610 GET_BE_U_2(opt + i + cap_offset)),
2611 GET_BE_U_2(opt + i + cap_offset),
2612 tok2str(bgp_safi_values,"Unknown",
2613 GET_U_1(opt + i + cap_offset + 2)),
2614 GET_U_1(opt + (i + cap_offset + 2)),
2615 ((GET_U_1(opt + (i + cap_offset + 3)))&0x80) ? "yes" : "no" );
2616 tcap_len -= 4;
2617 cap_offset += 4;
2618 }
2619 break;
2620 case BGP_CAPCODE_RR:
2621 case BGP_CAPCODE_LLGR:
2622 case BGP_CAPCODE_RR_CISCO:
2623 break;
2624 case BGP_CAPCODE_AS_NEW:
2625 /*
2626 * Extract the 4 byte AS number encoded.
2627 */
2628 if (cap_len < 4) {
2629 ND_PRINT(" (too short, < 4)");
2630 return;
2631 }
2632 ND_PRINT("\n\t\t 4 Byte AS %s",
2633 as_printf(ndo, astostr, sizeof(astostr),
2634 GET_BE_U_4(opt + i + 2)));
2635 break;
2636 case BGP_CAPCODE_ADD_PATH:
2637 if (cap_len == 0) {
2638 ND_PRINT(" (bogus)"); /* length */
2639 break;
2640 }
2641 tcap_len=cap_len;
2642 cap_offset=2;
2643 while (tcap_len != 0) {
2644 if (tcap_len < 4) {
2645 nd_print_invalid(ndo);
2646 break;
2647 }
2648 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u), Send/Receive: %s",
2649 tok2str(af_values,"Unknown",GET_BE_U_2(opt + i + cap_offset)),
2650 GET_BE_U_2(opt + i + cap_offset),
2651 tok2str(bgp_safi_values,"Unknown",GET_U_1(opt + i + cap_offset + 2)),
2652 GET_U_1(opt + (i + cap_offset + 2)),
2653 tok2str(bgp_add_path_recvsend,"Bogus (0x%02x)",GET_U_1(opt + i + cap_offset + 3))
2654 );
2655 tcap_len -= 4;
2656 cap_offset += 4;
2657 }
2658 break;
2659 default:
2660 ND_PRINT("\n\t\tno decoder for Capability %u",
2661 cap_type);
2662 if (ndo->ndo_vflag <= 1)
2663 print_unknown_data(ndo, opt + i + 2, "\n\t\t",
2664 cap_len);
2665 break;
2666 }
2667 if (ndo->ndo_vflag > 1 && cap_len != 0) {
2668 print_unknown_data(ndo, opt + i + 2, "\n\t\t", cap_len);
2669 }
2670 i += BGP_CAP_HEADER_SIZE + cap_len;
2671 }
2672 return;
2673
2674 trunc:
2675 nd_print_trunc(ndo);
2676 }
2677
2678 static void
2679 bgp_open_print(netdissect_options *ndo,
2680 const u_char *dat, u_int length)
2681 {
2682 const struct bgp_open *bgp_open_header;
2683 u_int optslen;
2684 const struct bgp_opt *bgpopt;
2685 const u_char *opt;
2686 u_int i;
2687
2688 ND_TCHECK_LEN(dat, BGP_OPEN_SIZE);
2689 if (length < BGP_OPEN_SIZE)
2690 goto trunc;
2691
2692 bgp_open_header = (const struct bgp_open *)dat;
2693
2694 ND_PRINT("\n\t Version %u, ",
2695 GET_U_1(bgp_open_header->bgpo_version));
2696 ND_PRINT("my AS %s, ",
2697 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(bgp_open_header->bgpo_myas)));
2698 ND_PRINT("Holdtime %us, ",
2699 GET_BE_U_2(bgp_open_header->bgpo_holdtime));
2700 ND_PRINT("ID %s", GET_IPADDR_STRING(bgp_open_header->bgpo_id));
2701 optslen = GET_U_1(bgp_open_header->bgpo_optlen);
2702 ND_PRINT("\n\t Optional parameters, length: %u", optslen);
2703
2704 opt = dat + BGP_OPEN_SIZE;
2705 length -= BGP_OPEN_SIZE;
2706
2707 i = 0;
2708 while (i < optslen) {
2709 uint8_t opt_type, opt_len;
2710
2711 ND_TCHECK_LEN(opt + i, BGP_OPT_SIZE);
2712 if (length < BGP_OPT_SIZE + i)
2713 goto trunc;
2714 bgpopt = (const struct bgp_opt *)(opt + i);
2715 opt_type = GET_U_1(bgpopt->bgpopt_type);
2716 opt_len = GET_U_1(bgpopt->bgpopt_len);
2717 if (BGP_OPT_SIZE + i + opt_len > optslen) {
2718 ND_PRINT("\n\t Option %u, length: %u, goes past the end of the options",
2719 opt_type, opt_len);
2720 break;
2721 }
2722
2723 ND_PRINT("\n\t Option %s (%u), length: %u",
2724 tok2str(bgp_opt_values,"Unknown",opt_type),
2725 opt_type,
2726 opt_len);
2727
2728 /* now let's decode the options we know*/
2729 switch(opt_type) {
2730
2731 case BGP_OPT_CAP:
2732 bgp_capabilities_print(ndo, opt + BGP_OPT_SIZE + i,
2733 opt_len);
2734 break;
2735
2736 case BGP_OPT_AUTH:
2737 default:
2738 ND_PRINT("\n\t no decoder for option %u",
2739 opt_type);
2740 break;
2741 }
2742 i += BGP_OPT_SIZE + opt_len;
2743 }
2744 return;
2745 trunc:
2746 nd_print_trunc(ndo);
2747 }
2748
2749 static void
2750 bgp_update_print(netdissect_options *ndo,
2751 const u_char *dat, u_int length)
2752 {
2753 const u_char *p;
2754 u_int withdrawn_routes_len;
2755 char buf[MAXHOSTNAMELEN + 100];
2756 int wpfx;
2757 u_int len;
2758 int i;
2759 int add_path;
2760 u_int path_id = 0;
2761
2762 ND_TCHECK_LEN(dat, BGP_SIZE);
2763 if (length < BGP_SIZE)
2764 goto trunc;
2765 p = dat + BGP_SIZE;
2766 length -= BGP_SIZE;
2767
2768 /* Unfeasible routes */
2769 ND_TCHECK_2(p);
2770 if (length < 2)
2771 goto trunc;
2772 withdrawn_routes_len = GET_BE_U_2(p);
2773 p += 2;
2774 length -= 2;
2775 if (withdrawn_routes_len > 1) {
2776 /*
2777 * Without keeping state from the original NLRI message,
2778 * it's not possible to tell if this a v4 or v6 route,
2779 * so only try to decode it if we're not v6 enabled.
2780 */
2781 ND_TCHECK_LEN(p, withdrawn_routes_len);
2782 if (length < withdrawn_routes_len)
2783 goto trunc;
2784 ND_PRINT("\n\t Withdrawn routes:");
2785 add_path = check_add_path(ndo, p, withdrawn_routes_len, 32);
2786 while (withdrawn_routes_len != 0) {
2787 if (add_path) {
2788 if (withdrawn_routes_len < 4) {
2789 p += withdrawn_routes_len;
2790 length -= withdrawn_routes_len;
2791 break;
2792 }
2793 path_id = GET_BE_U_4(p);
2794 p += 4;
2795 length -= 4;
2796 withdrawn_routes_len -= 4;
2797 }
2798 wpfx = decode_prefix4(ndo, p, withdrawn_routes_len, buf, sizeof(buf));
2799 if (wpfx == -1) {
2800 ND_PRINT("\n\t (illegal prefix length)");
2801 break;
2802 } else if (wpfx == -2)
2803 goto trunc;
2804 else if (wpfx == -3)
2805 goto trunc; /* bytes left, but not enough */
2806 else {
2807 ND_PRINT("\n\t %s", buf);
2808 if (add_path) {
2809 ND_PRINT(" Path Id: %u", path_id);
2810 }
2811 p += wpfx;
2812 length -= wpfx;
2813 withdrawn_routes_len -= wpfx;
2814 }
2815 }
2816 } else {
2817 ND_TCHECK_LEN(p, withdrawn_routes_len);
2818 if (length < withdrawn_routes_len)
2819 goto trunc;
2820 p += withdrawn_routes_len;
2821 length -= withdrawn_routes_len;
2822 }
2823
2824 ND_TCHECK_2(p);
2825 if (length < 2)
2826 goto trunc;
2827 len = GET_BE_U_2(p);
2828 p += 2;
2829 length -= 2;
2830
2831 if (withdrawn_routes_len == 0 && len == 0 && length == 0) {
2832 /* No withdrawn routes, no path attributes, no NLRI */
2833 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2834 return;
2835 }
2836
2837 if (len) {
2838 /* do something more useful!*/
2839 while (len) {
2840 uint8_t aflags, atype, alenlen;
2841 uint16_t alen;
2842
2843 ND_TCHECK_2(p);
2844 if (length < 2)
2845 goto trunc;
2846 if (len < 2) {
2847 ND_PRINT("\n\t [path attrs too short]");
2848 p += len;
2849 length -= len;
2850 break;
2851 }
2852 aflags = GET_U_1(p);
2853 atype = GET_U_1(p + 1);
2854 p += 2;
2855 len -= 2;
2856 length -= 2;
2857 alenlen = bgp_attr_lenlen(aflags, p);
2858 ND_TCHECK_LEN(p, alenlen);
2859 if (length < alenlen)
2860 goto trunc;
2861 if (len < alenlen) {
2862 ND_PRINT("\n\t [path attrs too short]");
2863 p += len;
2864 length -= len;
2865 break;
2866 }
2867 alen = bgp_attr_len(aflags, p);
2868 p += alenlen;
2869 len -= alenlen;
2870 length -= alenlen;
2871
2872 ND_PRINT("\n\t %s (%u), length: %u",
2873 tok2str(bgp_attr_values, "Unknown Attribute", atype),
2874 atype,
2875 alen);
2876
2877 if (aflags) {
2878 ND_PRINT(", Flags [%s%s%s%s",
2879 aflags & 0x80 ? "O" : "",
2880 aflags & 0x40 ? "T" : "",
2881 aflags & 0x20 ? "P" : "",
2882 aflags & 0x10 ? "E" : "");
2883 if (aflags & 0xf)
2884 ND_PRINT("+%x", aflags & 0xf);
2885 ND_PRINT("]: ");
2886 }
2887 if (len < alen) {
2888 ND_PRINT(" [path attrs too short]");
2889 p += len;
2890 length -= len;
2891 break;
2892 }
2893 if (length < alen)
2894 goto trunc;
2895 if (!bgp_attr_print(ndo, atype, p, alen, 0))
2896 goto trunc;
2897 p += alen;
2898 len -= alen;
2899 length -= alen;
2900 }
2901 }
2902
2903 if (length) {
2904 add_path = check_add_path(ndo, p, length, 32);
2905 ND_PRINT("\n\t Updated routes:");
2906 while (length != 0) {
2907 if (add_path) {
2908 ND_TCHECK_4(p);
2909 if (length < 4)
2910 goto trunc;
2911 path_id = GET_BE_U_4(p);
2912 p += 4;
2913 length -= 4;
2914 }
2915 i = decode_prefix4(ndo, p, length, buf, sizeof(buf));
2916 if (i == -1) {
2917 ND_PRINT("\n\t (illegal prefix length)");
2918 break;
2919 } else if (i == -2)
2920 goto trunc;
2921 else if (i == -3)
2922 goto trunc; /* bytes left, but not enough */
2923 else {
2924 ND_PRINT("\n\t %s", buf);
2925 if (add_path) {
2926 ND_PRINT(" Path Id: %u", path_id);
2927 }
2928 p += i;
2929 length -= i;
2930 }
2931 }
2932 }
2933 return;
2934 trunc:
2935 nd_print_trunc(ndo);
2936 }
2937
2938 static void
2939 bgp_notification_print(netdissect_options *ndo,
2940 const u_char *dat, u_int length)
2941 {
2942 const struct bgp_notification *bgp_notification_header;
2943 const u_char *tptr;
2944 uint8_t bgpn_major, bgpn_minor;
2945 uint8_t shutdown_comm_length;
2946 uint8_t remainder_offset;
2947
2948 ND_TCHECK_LEN(dat, BGP_NOTIFICATION_SIZE);
2949 if (length<BGP_NOTIFICATION_SIZE)
2950 return;
2951
2952 bgp_notification_header = (const struct bgp_notification *)dat;
2953 bgpn_major = GET_U_1(bgp_notification_header->bgpn_major);
2954 bgpn_minor = GET_U_1(bgp_notification_header->bgpn_minor);
2955
2956 ND_PRINT(", %s (%u)",
2957 tok2str(bgp_notify_major_values, "Unknown Error",
2958 bgpn_major),
2959 bgpn_major);
2960
2961 switch (bgpn_major) {
2962
2963 case BGP_NOTIFY_MAJOR_MSG:
2964 ND_PRINT(", subcode %s (%u)",
2965 tok2str(bgp_notify_minor_msg_values, "Unknown",
2966 bgpn_minor),
2967 bgpn_minor);
2968 break;
2969 case BGP_NOTIFY_MAJOR_OPEN:
2970 ND_PRINT(", subcode %s (%u)",
2971 tok2str(bgp_notify_minor_open_values, "Unknown",
2972 bgpn_minor),
2973 bgpn_minor);
2974 break;
2975 case BGP_NOTIFY_MAJOR_UPDATE:
2976 ND_PRINT(", subcode %s (%u)",
2977 tok2str(bgp_notify_minor_update_values, "Unknown",
2978 bgpn_minor),
2979 bgpn_minor);
2980 break;
2981 case BGP_NOTIFY_MAJOR_FSM:
2982 ND_PRINT(" subcode %s (%u)",
2983 tok2str(bgp_notify_minor_fsm_values, "Unknown",
2984 bgpn_minor),
2985 bgpn_minor);
2986 break;
2987 case BGP_NOTIFY_MAJOR_CAP:
2988 ND_PRINT(" subcode %s (%u)",
2989 tok2str(bgp_notify_minor_cap_values, "Unknown",
2990 bgpn_minor),
2991 bgpn_minor);
2992 break;
2993 case BGP_NOTIFY_MAJOR_CEASE:
2994 ND_PRINT(", subcode %s (%u)",
2995 tok2str(bgp_notify_minor_cease_values, "Unknown",
2996 bgpn_minor),
2997 bgpn_minor);
2998
2999 /* draft-ietf-idr-cease-subcode-02 mentions optionally 7 bytes
3000 * for the maxprefix subtype, which may contain AFI, SAFI and MAXPREFIXES
3001 */
3002 if(bgpn_minor == BGP_NOTIFY_MINOR_CEASE_MAXPRFX && length >= BGP_NOTIFICATION_SIZE + 7) {
3003 tptr = dat + BGP_NOTIFICATION_SIZE;
3004 ND_PRINT(", AFI %s (%u), SAFI %s (%u), Max Prefixes: %u",
3005 tok2str(af_values, "Unknown", GET_BE_U_2(tptr)),
3006 GET_BE_U_2(tptr),
3007 tok2str(bgp_safi_values, "Unknown", GET_U_1((tptr + 2))),
3008 GET_U_1((tptr + 2)),
3009 GET_BE_U_4(tptr + 3));
3010 }
3011 /*
3012 * draft-ietf-idr-shutdown describes a method to send a communication
3013 * intended for human consumption regarding the Administrative Shutdown
3014 */
3015 if ((bgpn_minor == BGP_NOTIFY_MINOR_CEASE_SHUT ||
3016 bgpn_minor == BGP_NOTIFY_MINOR_CEASE_RESET) &&
3017 length >= BGP_NOTIFICATION_SIZE + 1) {
3018 tptr = dat + BGP_NOTIFICATION_SIZE;
3019 shutdown_comm_length = GET_U_1(tptr);
3020 remainder_offset = 0;
3021 /* garbage, hexdump it all */
3022 if (shutdown_comm_length > BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN ||
3023 shutdown_comm_length > length - (BGP_NOTIFICATION_SIZE + 1)) {
3024 ND_PRINT(", invalid Shutdown Communication length");
3025 }
3026 else if (shutdown_comm_length == 0) {
3027 ND_PRINT(", empty Shutdown Communication");
3028 remainder_offset += 1;
3029 }
3030 /* a proper shutdown communication */
3031 else {
3032 ND_TCHECK_LEN(tptr + 1, shutdown_comm_length);
3033 ND_PRINT(", Shutdown Communication (length: %u): \"", shutdown_comm_length);
3034 (void)nd_printn(ndo, tptr+1, shutdown_comm_length, NULL);
3035 ND_PRINT("\"");
3036 remainder_offset += shutdown_comm_length + 1;
3037 }
3038 /* if there is trailing data, hexdump it */
3039 if(length - (remainder_offset + BGP_NOTIFICATION_SIZE) > 0) {
3040 ND_PRINT(", Data: (length: %u)", length - (remainder_offset + BGP_NOTIFICATION_SIZE));
3041 hex_print(ndo, "\n\t\t", tptr + remainder_offset, length - (remainder_offset + BGP_NOTIFICATION_SIZE));
3042 }
3043 }
3044 break;
3045 default:
3046 break;
3047 }
3048
3049 return;
3050 trunc:
3051 nd_print_trunc(ndo);
3052 }
3053
3054 static void
3055 bgp_route_refresh_print(netdissect_options *ndo,
3056 const u_char *pptr, u_int len)
3057 {
3058 const struct bgp_route_refresh *bgp_route_refresh_header;
3059
3060 ND_TCHECK_LEN(pptr, BGP_ROUTE_REFRESH_SIZE);
3061
3062 /* some little sanity checking */
3063 if (len<BGP_ROUTE_REFRESH_SIZE)
3064 return;
3065
3066 bgp_route_refresh_header = (const struct bgp_route_refresh *)pptr;
3067
3068 ND_PRINT("\n\t AFI %s (%u), SAFI %s (%u)",
3069 tok2str(af_values,"Unknown",
3070 GET_BE_U_2(bgp_route_refresh_header->afi)),
3071 GET_BE_U_2(bgp_route_refresh_header->afi),
3072 tok2str(bgp_safi_values,"Unknown",
3073 GET_U_1(bgp_route_refresh_header->safi)),
3074 GET_U_1(bgp_route_refresh_header->safi));
3075
3076 if (ndo->ndo_vflag > 1) {
3077 ND_TCHECK_LEN(pptr, len);
3078 print_unknown_data(ndo, pptr, "\n\t ", len);
3079 }
3080
3081 return;
3082 trunc:
3083 nd_print_trunc(ndo);
3084 }
3085
3086 static int
3087 bgp_pdu_print(netdissect_options *ndo,
3088 const u_char *dat, u_int length)
3089 {
3090 const struct bgp *bgp_header;
3091 uint8_t bgp_type;
3092
3093 ND_TCHECK_LEN(dat, BGP_SIZE);
3094 bgp_header = (const struct bgp *)dat;
3095 bgp_type = GET_U_1(bgp_header->bgp_type);
3096
3097 ND_PRINT("\n\t%s Message (%u), length: %u",
3098 tok2str(bgp_msg_values, "Unknown", bgp_type),
3099 bgp_type,
3100 length);
3101
3102 switch (bgp_type) {
3103 case BGP_OPEN:
3104 bgp_open_print(ndo, dat, length);
3105 break;
3106 case BGP_UPDATE:
3107 bgp_update_print(ndo, dat, length);
3108 break;
3109 case BGP_NOTIFICATION:
3110 bgp_notification_print(ndo, dat, length);
3111 break;
3112 case BGP_KEEPALIVE:
3113 break;
3114 case BGP_ROUTE_REFRESH:
3115 bgp_route_refresh_print(ndo, dat, length);
3116 break;
3117 default:
3118 /* we have no decoder for the BGP message */
3119 ND_TCHECK_LEN(dat, length);
3120 ND_PRINT("\n\t no Message %u decoder", bgp_type);
3121 print_unknown_data(ndo, dat, "\n\t ", length);
3122 break;
3123 }
3124 return 1;
3125 trunc:
3126 nd_print_trunc(ndo);
3127 return 0;
3128 }
3129
3130 void
3131 bgp_print(netdissect_options *ndo,
3132 const u_char *dat, u_int length _U_)
3133 {
3134 const u_char *p;
3135 const u_char *ep = ndo->ndo_snapend;
3136 const u_char *start;
3137 const u_char marker[] = {
3138 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3139 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3140 };
3141 const struct bgp *bgp_header;
3142 uint16_t hlen;
3143
3144 ndo->ndo_protocol = "bgp";
3145 ND_PRINT(": BGP");
3146
3147 if (ndo->ndo_vflag < 1) /* lets be less chatty */
3148 return;
3149
3150 p = dat;
3151 start = p;
3152 while (p < ep) {
3153 if (!ND_TTEST_1(p))
3154 break;
3155 if (GET_U_1(p) != 0xff) {
3156 p++;
3157 continue;
3158 }
3159
3160 if (!ND_TTEST_LEN(p, sizeof(marker)))
3161 break;
3162 if (memcmp(p, marker, sizeof(marker)) != 0) {
3163 p++;
3164 continue;
3165 }
3166
3167 /* found BGP header */
3168 ND_TCHECK_LEN(p, BGP_SIZE);
3169 bgp_header = (const struct bgp *)p;
3170
3171 if (start != p)
3172 nd_print_trunc(ndo);
3173
3174 hlen = GET_BE_U_2(bgp_header->bgp_len);
3175 if (hlen < BGP_SIZE) {
3176 ND_PRINT("\nmessage length %u < %u", hlen, BGP_SIZE);
3177 nd_print_invalid(ndo);
3178 break;
3179 }
3180
3181 if (ND_TTEST_LEN(p, hlen)) {
3182 if (!bgp_pdu_print(ndo, p, hlen))
3183 return;
3184 p += hlen;
3185 start = p;
3186 } else {
3187 ND_PRINT("\n[|BGP %s]",
3188 tok2str(bgp_msg_values,
3189 "Unknown Message Type",
3190 GET_U_1(bgp_header->bgp_type)));
3191 break;
3192 }
3193 }
3194
3195 return;
3196
3197 trunc:
3198 nd_print_trunc(ndo);
3199 }
[mirror] the TCPdump network dissector