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Don't run past the end of an MP_REACH_NLRI attribute.
[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 static char astostr[20];
561
562 /*
563 * as_printf
564 *
565 * Convert an AS number into a string and return string pointer.
566 *
567 * Depending on bflag is set or not, AS number is converted into ASDOT notation
568 * or plain number notation.
569 *
570 */
571 static char *
572 as_printf(netdissect_options *ndo,
573 char *str, size_t size, u_int asnum)
574 {
575 if (!ndo->ndo_bflag || asnum <= 0xFFFF) {
576 snprintf(str, size, "%u", asnum);
577 } else {
578 snprintf(str, size, "%u.%u", asnum >> 16, asnum & 0xFFFF);
579 }
580 return str;
581 }
582
583 #define ITEMCHECK(minlen) if (itemlen < minlen) goto badtlv;
584
585 int
586 decode_prefix4(netdissect_options *ndo,
587 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
588 {
589 nd_ipv4 addr;
590 u_int plen, plenbytes;
591
592 ND_TCHECK_1(pptr);
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 ND_TCHECK_LEN(pptr, sizeof(nd_ipv4));
688 snprintf(pos, sizeof(addr), "%s", ipaddr_string(ndo, pptr));
689 break;
690 case (sizeof(nd_ipv6) << 3): /* 128 */
691 ND_TCHECK_LEN(pptr, sizeof(nd_ipv6));
692 snprintf(pos, sizeof(addr), "%s", ip6addr_string(ndo, pptr));
693 break;
694 default:
695 snprintf(pos, sizeof(addr), "bogus address length %u", addr_length);
696 break;
697 }
698 pos += strlen(pos);
699
700 trunc:
701 *(pos) = '\0';
702 return (addr);
703 }
704
705 /*
706 * bgp_vpn_sg_print
707 *
708 * print an multicast s,g entry into a buffer.
709 * the s,g entry is encoded like this.
710 *
711 * +-----------------------------------+
712 * | Multicast Source Length (1 octet) |
713 * +-----------------------------------+
714 * | Multicast Source (Variable) |
715 * +-----------------------------------+
716 * | Multicast Group Length (1 octet) |
717 * +-----------------------------------+
718 * | Multicast Group (Variable) |
719 * +-----------------------------------+
720 *
721 * return the number of bytes read from the wire.
722 */
723 static u_int
724 bgp_vpn_sg_print(netdissect_options *ndo,
725 const u_char *pptr, char *buf, size_t buflen)
726 {
727 uint8_t addr_length;
728 u_int total_length, offset;
729
730 total_length = 0;
731
732 /* Source address length, encoded in bits */
733 ND_TCHECK_1(pptr);
734 addr_length = GET_U_1(pptr);
735 pptr++;
736
737 /* Source address */
738 ND_TCHECK_LEN(pptr, (addr_length >> 3));
739 total_length += (addr_length >> 3) + 1;
740 offset = (u_int)strlen(buf);
741 if (addr_length) {
742 snprintf(buf + offset, buflen - offset, ", Source %s",
743 bgp_vpn_ip_print(ndo, pptr, addr_length));
744 pptr += (addr_length >> 3);
745 }
746
747 /* Group address length, encoded in bits */
748 ND_TCHECK_1(pptr);
749 addr_length = GET_U_1(pptr);
750 pptr++;
751
752 /* Group address */
753 ND_TCHECK_LEN(pptr, (addr_length >> 3));
754 total_length += (addr_length >> 3) + 1;
755 offset = (u_int)strlen(buf);
756 if (addr_length) {
757 snprintf(buf + offset, buflen - offset, ", Group %s",
758 bgp_vpn_ip_print(ndo, pptr, addr_length));
759 pptr += (addr_length >> 3);
760 }
761
762 trunc:
763 return (total_length);
764 }
765
766 /* Print an RFC 4364 Route Distinguisher */
767 const char *
768 bgp_vpn_rd_print(netdissect_options *ndo,
769 const u_char *pptr)
770 {
771 /* allocate space for the largest possible string */
772 static char rd[sizeof("xxxxxxxxxx:xxxxx (xxx.xxx.xxx.xxx:xxxxx)")];
773 char *pos = rd;
774
775 /* ok lets load the RD format */
776 switch (GET_BE_U_2(pptr)) {
777
778 case 0:
779 /* 2-byte-AS:number fmt */
780 snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (= %u.%u.%u.%u)",
781 GET_BE_U_2(pptr + 2),
782 GET_BE_U_4(pptr + 4),
783 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
784 GET_U_1(pptr + 6), GET_U_1(pptr + 7));
785 break;
786
787 case 1:
788 /* IP-address:AS fmt */
789 snprintf(pos, sizeof(rd) - (pos - rd), "%u.%u.%u.%u:%u",
790 GET_U_1(pptr + 2), GET_U_1(pptr + 3),
791 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
792 GET_BE_U_2(pptr + 6));
793 break;
794
795 case 2:
796 /* 4-byte-AS:number fmt */
797 snprintf(pos, sizeof(rd) - (pos - rd), "%s:%u (%u.%u.%u.%u:%u)",
798 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 2)),
799 GET_BE_U_2(pptr + 6), GET_U_1(pptr + 2),
800 GET_U_1(pptr + 3), GET_U_1(pptr + 4),
801 GET_U_1(pptr + 5), GET_BE_U_2(pptr + 6));
802 break;
803 default:
804 snprintf(pos, sizeof(rd) - (pos - rd), "unknown RD format");
805 break;
806 }
807 pos += strlen(pos);
808 *(pos) = '\0';
809 return (rd);
810 }
811
812 /*
813 * Print an RFC 4360 Extended Community.
814 */
815 static void
816 bgp_extended_community_print(netdissect_options *ndo,
817 const u_char *pptr)
818 {
819 union { /* copy buffer for bandwidth values */
820 float f;
821 uint32_t i;
822 } bw;
823
824 switch (GET_BE_U_2(pptr)) {
825
826 case BGP_EXT_COM_RT_0:
827 case BGP_EXT_COM_RO_0:
828 case BGP_EXT_COM_L2VPN_RT_0:
829 ND_PRINT("%u:%u (= %s)",
830 GET_BE_U_2(pptr + 2),
831 GET_BE_U_4(pptr + 4),
832 ipaddr_string(ndo, pptr+4));
833 break;
834
835 case BGP_EXT_COM_RT_1:
836 case BGP_EXT_COM_RO_1:
837 case BGP_EXT_COM_L2VPN_RT_1:
838 case BGP_EXT_COM_VRF_RT_IMP:
839 ND_PRINT("%s:%u",
840 ipaddr_string(ndo, pptr+2),
841 GET_BE_U_2(pptr + 6));
842 break;
843
844 case BGP_EXT_COM_RT_2:
845 case BGP_EXT_COM_RO_2:
846 ND_PRINT("%s:%u",
847 as_printf(ndo, astostr, sizeof(astostr),
848 GET_BE_U_4(pptr + 2)), GET_BE_U_2(pptr + 6));
849 break;
850
851 case BGP_EXT_COM_LINKBAND:
852 bw.i = GET_BE_U_4(pptr + 2);
853 ND_PRINT("bandwidth: %.3f Mbps",
854 bw.f*8/1000000);
855 break;
856
857 case BGP_EXT_COM_VPN_ORIGIN:
858 case BGP_EXT_COM_VPN_ORIGIN2:
859 case BGP_EXT_COM_VPN_ORIGIN3:
860 case BGP_EXT_COM_VPN_ORIGIN4:
861 case BGP_EXT_COM_OSPF_RID:
862 case BGP_EXT_COM_OSPF_RID2:
863 ND_PRINT("%s", ipaddr_string(ndo, pptr+2));
864 break;
865
866 case BGP_EXT_COM_OSPF_RTYPE:
867 case BGP_EXT_COM_OSPF_RTYPE2:
868 ND_PRINT("area:%s, router-type:%s, metric-type:%s%s",
869 ipaddr_string(ndo, pptr+2),
870 tok2str(bgp_extd_comm_ospf_rtype_values,
871 "unknown (0x%02x)",
872 GET_U_1((pptr + 6))),
873 (GET_U_1(pptr + 7) & BGP_OSPF_RTYPE_METRIC_TYPE) ? "E2" : "",
874 ((GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_EXT) || (GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_NSSA)) ? "E1" : "");
875 break;
876
877 case BGP_EXT_COM_L2INFO:
878 ND_PRINT("%s Control Flags [0x%02x]:MTU %u",
879 tok2str(l2vpn_encaps_values,
880 "unknown encaps",
881 GET_U_1((pptr + 2))),
882 GET_U_1((pptr + 3)),
883 GET_BE_U_2(pptr + 4));
884 break;
885
886 case BGP_EXT_COM_SOURCE_AS:
887 ND_PRINT("AS %u", GET_BE_U_2(pptr + 2));
888 break;
889
890 case BGP_EXT_COM_ENCAP:
891 ND_PRINT("Tunnel type: %s", tok2str(bgp_extd_comm_encap_tunnel_values,
892 "unknown encaps",
893 GET_BE_U_2(pptr + 6)));
894 break;
895
896 default:
897 ND_PRINT("%02x%02x%02x%02x%02x%02x",
898 GET_U_1(pptr + 2),
899 GET_U_1(pptr + 3),
900 GET_U_1(pptr + 4),
901 GET_U_1(pptr + 5),
902 GET_U_1(pptr + 6),
903 GET_U_1(pptr + 7));
904 break;
905 }
906 }
907
908 /* RFC 4684 */
909 static int
910 decode_rt_routing_info(netdissect_options *ndo,
911 const u_char *pptr)
912 {
913 u_int plen;
914 char asbuf[sizeof(astostr)]; /* bgp_vpn_rd_print() overwrites astostr */
915
916 /* NLRI "prefix length" from RFC 2858 Section 4. */
917 ND_TCHECK_1(pptr);
918 plen = GET_U_1(pptr); /* get prefix length */
919
920 /* NLRI "prefix" (ibid), valid lengths are { 0, 32, 33, ..., 96 } bits.
921 * RFC 4684 Section 4 defines the layout of "origin AS" and "route
922 * target" fields inside the "prefix" depending on its length.
923 */
924 if (0 == plen) {
925 /* Without "origin AS", without "route target". */
926 ND_PRINT("\n\t default route target");
927 return 1;
928 }
929
930 if (32 > plen) {
931 ND_PRINT("\n\t (illegal prefix length)");
932 return -1;
933 }
934
935 /* With at least "origin AS", possibly with "route target". */
936 ND_TCHECK_4(pptr + 1);
937 as_printf(ndo, asbuf, sizeof(asbuf), GET_BE_U_4(pptr + 1));
938
939 plen -= 32; /* adjust prefix length */
940
941 /* An extended community is 8 octets, so the remaining prefix
942 * length must be 64.
943 */
944 if (64 != plen) {
945 ND_PRINT("\n\t (illegal prefix length)");
946 return -1;
947 }
948 ND_TCHECK_LEN(pptr + 5, 8);
949 ND_PRINT("\n\t origin AS: %s, route target ", asbuf);
950 bgp_extended_community_print(ndo, pptr + 5);
951
952 return 5 + 8;
953
954 trunc:
955 return -2;
956 }
957
958 static int
959 decode_labeled_vpn_prefix4(netdissect_options *ndo,
960 const u_char *pptr, char *buf, size_t buflen)
961 {
962 nd_ipv4 addr;
963 u_int plen;
964
965 ND_TCHECK_1(pptr);
966 plen = GET_U_1(pptr); /* get prefix length */
967
968 if ((24+64) > plen)
969 return -1;
970
971 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
972
973 if (32 < plen)
974 return -1;
975
976 memset(&addr, 0, sizeof(addr));
977 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
978 memcpy(&addr, pptr + 12, (plen + 7) / 8);
979 if (plen % 8) {
980 ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
981 ((0xff00 >> (plen % 8)) & 0xff);
982 }
983 /* the label may get offsetted by 4 bits so lets shift it right */
984 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
985 bgp_vpn_rd_print(ndo, pptr+4),
986 ipaddr_string(ndo, (const u_char *)&addr),
987 plen,
988 GET_BE_U_3(pptr + 1)>>4,
989 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
990
991 return 12 + (plen + 7) / 8;
992
993 trunc:
994 return -2;
995 }
996
997 /*
998 * +-------------------------------+
999 * | |
1000 * | RD:IPv4-address (12 octets) |
1001 * | |
1002 * +-------------------------------+
1003 * | MDT Group-address (4 octets) |
1004 * +-------------------------------+
1005 */
1006
1007 #define MDT_VPN_NLRI_LEN 16
1008
1009 static int
1010 decode_mdt_vpn_nlri(netdissect_options *ndo,
1011 const u_char *pptr, char *buf, size_t buflen)
1012 {
1013 const u_char *rd;
1014 const u_char *vpn_ip;
1015
1016 ND_TCHECK_1(pptr);
1017
1018 /* if the NLRI is not predefined length, quit.*/
1019 if (GET_U_1(pptr) != MDT_VPN_NLRI_LEN * 8)
1020 return -1;
1021 pptr++;
1022
1023 /* RD */
1024 ND_TCHECK_8(pptr);
1025 rd = pptr;
1026 pptr += 8;
1027
1028 /* IPv4 address */
1029 ND_TCHECK_LEN(pptr, sizeof(nd_ipv4));
1030 vpn_ip = pptr;
1031 pptr += sizeof(nd_ipv4);
1032
1033 /* MDT Group Address */
1034 ND_TCHECK_LEN(pptr, sizeof(nd_ipv4));
1035
1036 snprintf(buf, buflen, "RD: %s, VPN IP Address: %s, MC Group Address: %s",
1037 bgp_vpn_rd_print(ndo, rd), ipaddr_string(ndo, vpn_ip), ipaddr_string(ndo, pptr));
1038
1039 return MDT_VPN_NLRI_LEN + 1;
1040
1041 trunc:
1042 return -2;
1043 }
1044
1045 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI 1
1046 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI 2
1047 #define BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI 3
1048 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF 4
1049 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE 5
1050 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN 6
1051 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN 7
1052
1053 static const struct tok bgp_multicast_vpn_route_type_values[] = {
1054 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI, "Intra-AS I-PMSI"},
1055 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI, "Inter-AS I-PMSI"},
1056 { BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI, "S-PMSI"},
1057 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF, "Intra-AS Segment-Leaf"},
1058 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE, "Source-Active"},
1059 { BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN, "Shared Tree Join"},
1060 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN, "Source Tree Join"},
1061 { 0, NULL}
1062 };
1063
1064 static int
1065 decode_multicast_vpn(netdissect_options *ndo,
1066 const u_char *pptr, char *buf, size_t buflen)
1067 {
1068 uint8_t route_type, route_length;
1069 u_int addr_length, sg_length;
1070 u_int offset;
1071
1072 ND_TCHECK_2(pptr);
1073 route_type = GET_U_1(pptr);
1074 pptr++;
1075 route_length = GET_U_1(pptr);
1076 pptr++;
1077
1078 snprintf(buf, buflen, "Route-Type: %s (%u), length: %u",
1079 tok2str(bgp_multicast_vpn_route_type_values,
1080 "Unknown", route_type),
1081 route_type, route_length);
1082
1083 switch(route_type) {
1084 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI:
1085 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1086 offset = (u_int)strlen(buf);
1087 snprintf(buf + offset, buflen - offset, ", RD: %s, Originator %s",
1088 bgp_vpn_rd_print(ndo, pptr),
1089 bgp_vpn_ip_print(ndo, pptr + BGP_VPN_RD_LEN,
1090 (route_length - BGP_VPN_RD_LEN) << 3));
1091 break;
1092 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI:
1093 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1094 offset = (u_int)strlen(buf);
1095 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1096 bgp_vpn_rd_print(ndo, pptr),
1097 as_printf(ndo, astostr, sizeof(astostr),
1098 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1099 break;
1100
1101 case BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI:
1102 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1103 offset = (u_int)strlen(buf);
1104 snprintf(buf + offset, buflen - offset, ", RD: %s",
1105 bgp_vpn_rd_print(ndo, pptr));
1106 pptr += BGP_VPN_RD_LEN;
1107
1108 sg_length = bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1109 addr_length = route_length - sg_length;
1110
1111 ND_TCHECK_LEN(pptr, addr_length);
1112 offset = (u_int)strlen(buf);
1113 snprintf(buf + offset, buflen - offset, ", Originator %s",
1114 bgp_vpn_ip_print(ndo, pptr, addr_length << 3));
1115 break;
1116
1117 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE:
1118 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1119 offset = (u_int)strlen(buf);
1120 snprintf(buf + offset, buflen - offset, ", RD: %s",
1121 bgp_vpn_rd_print(ndo, pptr));
1122 pptr += BGP_VPN_RD_LEN;
1123
1124 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1125 break;
1126
1127 case BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN: /* fall through */
1128 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN:
1129 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1130 offset = (u_int)strlen(buf);
1131 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1132 bgp_vpn_rd_print(ndo, pptr),
1133 as_printf(ndo, astostr, sizeof(astostr),
1134 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1135 pptr += BGP_VPN_RD_LEN + 4;
1136
1137 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1138 break;
1139
1140 /*
1141 * no per route-type printing yet.
1142 */
1143 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF:
1144 default:
1145 break;
1146 }
1147
1148 return route_length + 2;
1149
1150 trunc:
1151 return -2;
1152 }
1153
1154 /*
1155 * As I remember, some versions of systems have an snprintf() that
1156 * returns -1 if the buffer would have overflowed. If the return
1157 * value is negative, set buflen to 0, to indicate that we've filled
1158 * the buffer up.
1159 *
1160 * If the return value is greater than buflen, that means that
1161 * the buffer would have overflowed; again, set buflen to 0 in
1162 * that case.
1163 */
1164 #define UPDATE_BUF_BUFLEN(buf, buflen, stringlen) \
1165 if (stringlen<0) \
1166 buflen=0; \
1167 else if ((u_int)stringlen>buflen) \
1168 buflen=0; \
1169 else { \
1170 buflen-=stringlen; \
1171 buf+=stringlen; \
1172 }
1173
1174 static int
1175 decode_labeled_vpn_l2(netdissect_options *ndo,
1176 const u_char *pptr, char *buf, size_t buflen)
1177 {
1178 u_int plen, tlen, tlv_type, tlv_len, ttlv_len;
1179 int stringlen;
1180
1181 ND_TCHECK_2(pptr);
1182 plen = GET_BE_U_2(pptr);
1183 tlen = plen;
1184 pptr += 2;
1185 /* Old and new L2VPN NLRI share AFI/SAFI
1186 * -> Assume a 12 Byte-length NLRI is auto-discovery-only
1187 * and > 17 as old format. Complain for the middle case
1188 */
1189 if (plen == 12) {
1190 /* assume AD-only with RD, BGPNH */
1191 ND_TCHECK_LEN(pptr, 12);
1192 buf[0] = '\0';
1193 stringlen = snprintf(buf, buflen, "RD: %s, BGPNH: %s",
1194 bgp_vpn_rd_print(ndo, pptr),
1195 ipaddr_string(ndo, pptr+8));
1196 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1197 pptr += 12;
1198 tlen -= 12;
1199 return plen + 2;
1200 } else if (plen > 17) {
1201 /* assume old format */
1202 /* RD, ID, LBLKOFF, LBLBASE */
1203
1204 ND_TCHECK_LEN(pptr, 15);
1205 buf[0] = '\0';
1206 stringlen = snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u",
1207 bgp_vpn_rd_print(ndo, pptr),
1208 GET_BE_U_2(pptr + 8),
1209 GET_BE_U_2(pptr + 10),
1210 GET_BE_U_3(pptr + 12)>>4); /* the label is offsetted by 4 bits so lets shift it right */
1211 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1212 pptr += 15;
1213 tlen -= 15;
1214
1215 /* ok now the variable part - lets read out TLVs*/
1216 while (tlen != 0) {
1217 if (tlen < 3) {
1218 if (buflen != 0) {
1219 stringlen=snprintf(buf,buflen, "\n\t\tran past the end");
1220 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1221 }
1222 return plen + 2;
1223 }
1224 ND_TCHECK_3(pptr);
1225 tlv_type = GET_U_1(pptr);
1226 pptr++;
1227 tlv_len = GET_BE_U_2(pptr); /* length, in *bits* */
1228 ttlv_len = (tlv_len + 7)/8; /* length, in *bytes* */
1229 pptr += 2;
1230
1231 switch(tlv_type) {
1232 case 1:
1233 if (buflen != 0) {
1234 stringlen=snprintf(buf,buflen, "\n\t\tcircuit status vector (%u) length: %u: 0x",
1235 tlv_type,
1236 tlv_len);
1237 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1238 }
1239 while (ttlv_len != 0) {
1240 if (tlen < 1) {
1241 if (buflen != 0) {
1242 stringlen=snprintf(buf,buflen, " (ran past the end)");
1243 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1244 }
1245 return plen + 2;
1246 }
1247 ND_TCHECK_1(pptr);
1248 if (buflen != 0) {
1249 stringlen=snprintf(buf,buflen, "%02x",
1250 GET_U_1(pptr));
1251 pptr++;
1252 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1253 }
1254 ttlv_len--;
1255 tlen--;
1256 }
1257 break;
1258 default:
1259 if (buflen != 0) {
1260 stringlen=snprintf(buf,buflen, "\n\t\tunknown TLV #%u, length: %u",
1261 tlv_type,
1262 tlv_len);
1263 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1264 }
1265 if (tlen < ttlv_len) {
1266 if (buflen != 0) {
1267 stringlen=snprintf(buf,buflen, " (ran past the end)");
1268 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1269 }
1270 return plen + 2;
1271 }
1272 tlen -= ttlv_len;
1273 break;
1274 }
1275 }
1276 return plen + 2;
1277 } else {
1278 /* complain bitterly ? */
1279 /* fall through */
1280 goto trunc;
1281 }
1282
1283 trunc:
1284 return -2;
1285 }
1286
1287 int
1288 decode_prefix6(netdissect_options *ndo,
1289 const u_char *pd, u_int itemlen, char *buf, size_t buflen)
1290 {
1291 nd_ipv6 addr;
1292 u_int plen, plenbytes;
1293
1294 ND_TCHECK_1(pd);
1295 ITEMCHECK(1);
1296 plen = GET_U_1(pd);
1297 if (128 < plen)
1298 return -1;
1299 itemlen -= 1;
1300
1301 memset(&addr, 0, sizeof(addr));
1302 plenbytes = (plen + 7) / 8;
1303 ND_TCHECK_LEN(pd + 1, plenbytes);
1304 ITEMCHECK(plenbytes);
1305 memcpy(&addr, pd + 1, plenbytes);
1306 if (plen % 8) {
1307 addr[plenbytes - 1] &=
1308 ((0xff00 >> (plen % 8)) & 0xff);
1309 }
1310 snprintf(buf, buflen, "%s/%u", ip6addr_string(ndo, (const u_char *)&addr), plen);
1311 return 1 + plenbytes;
1312
1313 trunc:
1314 return -2;
1315
1316 badtlv:
1317 return -3;
1318 }
1319
1320 static int
1321 decode_labeled_prefix6(netdissect_options *ndo,
1322 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
1323 {
1324 nd_ipv6 addr;
1325 u_int plen, plenbytes;
1326
1327 /* prefix length and label = 4 bytes */
1328 ND_TCHECK_4(pptr);
1329 ITEMCHECK(4);
1330 plen = GET_U_1(pptr); /* get prefix length */
1331
1332 if (24 > plen)
1333 return -1;
1334
1335 plen -= 24; /* adjust prefixlen - labellength */
1336
1337 if (128 < plen)
1338 return -1;
1339 itemlen -= 4;
1340
1341 memset(&addr, 0, sizeof(addr));
1342 plenbytes = (plen + 7) / 8;
1343 ND_TCHECK_LEN(pptr + 4, plenbytes);
1344 memcpy(&addr, pptr + 4, plenbytes);
1345 if (plen % 8) {
1346 addr[plenbytes - 1] &=
1347 ((0xff00 >> (plen % 8)) & 0xff);
1348 }
1349 /* the label may get offsetted by 4 bits so lets shift it right */
1350 snprintf(buf, buflen, "%s/%u, label:%u %s",
1351 ip6addr_string(ndo, (const u_char *)&addr),
1352 plen,
1353 GET_BE_U_3(pptr + 1)>>4,
1354 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1355
1356 return 4 + plenbytes;
1357
1358 trunc:
1359 return -2;
1360
1361 badtlv:
1362 return -3;
1363 }
1364
1365 static int
1366 decode_labeled_vpn_prefix6(netdissect_options *ndo,
1367 const u_char *pptr, char *buf, size_t buflen)
1368 {
1369 nd_ipv6 addr;
1370 u_int plen;
1371
1372 ND_TCHECK_1(pptr);
1373 plen = GET_U_1(pptr); /* get prefix length */
1374
1375 if ((24+64) > plen)
1376 return -1;
1377
1378 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1379
1380 if (128 < plen)
1381 return -1;
1382
1383 memset(&addr, 0, sizeof(addr));
1384 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1385 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1386 if (plen % 8) {
1387 addr[(plen + 7) / 8 - 1] &=
1388 ((0xff00 >> (plen % 8)) & 0xff);
1389 }
1390 /* the label may get offsetted by 4 bits so lets shift it right */
1391 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1392 bgp_vpn_rd_print(ndo, pptr+4),
1393 ip6addr_string(ndo, (const u_char *)&addr),
1394 plen,
1395 GET_BE_U_3(pptr + 1)>>4,
1396 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1397
1398 return 12 + (plen + 7) / 8;
1399
1400 trunc:
1401 return -2;
1402 }
1403
1404 static int
1405 decode_clnp_prefix(netdissect_options *ndo,
1406 const u_char *pptr, char *buf, size_t buflen)
1407 {
1408 uint8_t addr[19];
1409 u_int plen;
1410
1411 ND_TCHECK_1(pptr);
1412 plen = GET_U_1(pptr); /* get prefix length */
1413
1414 if (152 < plen)
1415 return -1;
1416
1417 memset(&addr, 0, sizeof(addr));
1418 ND_TCHECK_LEN(pptr + 4, (plen + 7) / 8);
1419 memcpy(&addr, pptr + 4, (plen + 7) / 8);
1420 if (plen % 8) {
1421 addr[(plen + 7) / 8 - 1] &=
1422 ((0xff00 >> (plen % 8)) & 0xff);
1423 }
1424 snprintf(buf, buflen, "%s/%u",
1425 isonsap_string(ndo, addr,(plen + 7) / 8),
1426 plen);
1427
1428 return 1 + (plen + 7) / 8;
1429
1430 trunc:
1431 return -2;
1432 }
1433
1434 static int
1435 decode_labeled_vpn_clnp_prefix(netdissect_options *ndo,
1436 const u_char *pptr, char *buf, size_t buflen)
1437 {
1438 uint8_t addr[19];
1439 u_int plen;
1440
1441 ND_TCHECK_1(pptr);
1442 plen = GET_U_1(pptr); /* get prefix length */
1443
1444 if ((24+64) > plen)
1445 return -1;
1446
1447 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1448
1449 if (152 < plen)
1450 return -1;
1451
1452 memset(&addr, 0, sizeof(addr));
1453 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1454 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1455 if (plen % 8) {
1456 addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
1457 }
1458 /* the label may get offsetted by 4 bits so lets shift it right */
1459 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1460 bgp_vpn_rd_print(ndo, pptr+4),
1461 isonsap_string(ndo, addr,(plen + 7) / 8),
1462 plen,
1463 GET_BE_U_3(pptr + 1)>>4,
1464 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1465
1466 return 12 + (plen + 7) / 8;
1467
1468 trunc:
1469 return -2;
1470 }
1471
1472 /*
1473 * bgp_attr_get_as_size
1474 *
1475 * Try to find the size of the ASs encoded in an as-path. It is not obvious, as
1476 * both Old speakers that do not support 4 byte AS, and the new speakers that do
1477 * support, exchange AS-Path with the same path-attribute type value 0x02.
1478 */
1479 static u_int
1480 bgp_attr_get_as_size(netdissect_options *ndo,
1481 uint8_t bgpa_type, const u_char *pptr, u_int len)
1482 {
1483 const u_char *tptr = pptr;
1484
1485 /*
1486 * If the path attribute is the optional AS4 path type, then we already
1487 * know, that ASs must be encoded in 4 byte format.
1488 */
1489 if (bgpa_type == BGPTYPE_AS4_PATH) {
1490 return 4;
1491 }
1492
1493 /*
1494 * Let us assume that ASs are of 2 bytes in size, and check if the AS-Path
1495 * TLV is good. If not, ask the caller to try with AS encoded as 4 bytes
1496 * each.
1497 */
1498 while (tptr < pptr + len) {
1499 ND_TCHECK_1(tptr);
1500
1501 /*
1502 * If we do not find a valid segment type, our guess might be wrong.
1503 */
1504 if (GET_U_1(tptr) < BGP_AS_SEG_TYPE_MIN || GET_U_1(tptr) > BGP_AS_SEG_TYPE_MAX) {
1505 goto trunc;
1506 }
1507 ND_TCHECK_1(tptr + 1);
1508 tptr += 2 + GET_U_1(tptr + 1) * 2;
1509 }
1510
1511 /*
1512 * If we correctly reached end of the AS path attribute data content,
1513 * then most likely ASs were indeed encoded as 2 bytes.
1514 */
1515 if (tptr == pptr + len) {
1516 return 2;
1517 }
1518
1519 trunc:
1520
1521 /*
1522 * We can come here, either we did not have enough data, or if we
1523 * try to decode 4 byte ASs in 2 byte format. Either way, return 4,
1524 * so that calller can try to decode each AS as of 4 bytes. If indeed
1525 * there was not enough data, it will crib and end the parse anyways.
1526 */
1527 return 4;
1528 }
1529
1530 /*
1531 * The only way to know that a BGP UPDATE message is using add path is
1532 * by checking if the capability is in the OPEN message which we may have missed.
1533 * So this function checks if it is possible that the update could contain add path
1534 * and if so it checks that standard BGP doesn't make sense.
1535 */
1536 static int
1537 check_add_path(netdissect_options *ndo, const u_char *pptr, u_int length,
1538 u_int max_prefix_length)
1539 {
1540 u_int offset, prefix_length;
1541
1542 if (length < 5) {
1543 return 0;
1544 }
1545
1546 /*
1547 * Scan through the NLRI information under the assumpetion that
1548 * it doesn't have path IDs.
1549 */
1550 for (offset = 0; offset < length;) {
1551 offset += 4;
1552 if (!ND_TTEST_1(pptr + offset)) {
1553 /* We ran out of captured data; quit scanning. */
1554 break;
1555 }
1556 prefix_length = GET_U_1(pptr + offset);
1557 /*
1558 * Add 4 to cover the path id
1559 * and check the prefix length isn't greater than 32/128.
1560 */
1561 if (prefix_length > max_prefix_length) {
1562 return 0;
1563 }
1564 /* Add 1 for the prefix_length byte and prefix_length to cover the address */
1565 offset += 1 + ((prefix_length + 7) / 8);
1566 }
1567 /* check we haven't gone past the end of the section */
1568 if (offset > length) {
1569 return 0;
1570 }
1571
1572 /* check it's not standard BGP */
1573 for (offset = 0; offset < length; ) {
1574 if (!ND_TTEST_1(pptr + offset)) {
1575 /* We ran out of captured data; quit scanning. */
1576 break;
1577 }
1578 prefix_length = GET_U_1(pptr + offset);
1579 /*
1580 * If the prefix_length is zero (0.0.0.0/0)
1581 * and since it's not the only address (length >= 5)
1582 * then it is add-path
1583 */
1584 if (prefix_length < 1 || prefix_length > max_prefix_length) {
1585 return 1;
1586 }
1587 offset += 1 + ((prefix_length + 7) / 8);
1588 }
1589 if (offset > length) {
1590 return 1;
1591 }
1592
1593 /* assume not add-path by default */
1594 return 0;
1595 }
1596
1597 static int
1598 bgp_mp_af_print(netdissect_options *ndo,
1599 const u_char *tptr, u_int tlen,
1600 uint16_t *afp, uint8_t *safip)
1601 {
1602 uint16_t af;
1603 uint8_t safi;
1604
1605 af = GET_BE_U_2(tptr);
1606 *afp = af;
1607 safi = GET_U_1(tptr + 2);
1608 *safip = safi;
1609
1610 ND_PRINT("\n\t AFI: %s (%u), %sSAFI: %s (%u)",
1611 tok2str(af_values, "Unknown AFI", af),
1612 af,
1613 (safi>128) ? "vendor specific " : "", /* 128 is meanwhile wellknown */
1614 tok2str(bgp_safi_values, "Unknown SAFI", safi),
1615 safi);
1616
1617 switch(af<<8 | safi) {
1618 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1619 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1620 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1621 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1622 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1623 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1624 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1625 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1626 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
1627 case (AFNUM_INET<<8 | SAFNUM_MDT):
1628 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1629 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1630 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1631 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1632 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1633 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1634 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1635 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1636 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1637 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1638 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1639 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1640 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1641 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1642 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1643 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1644 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1645 break;
1646 default:
1647 ND_TCHECK_LEN(tptr, tlen);
1648 ND_PRINT("\n\t no AFI %u / SAFI %u decoder", af, safi);
1649 if (ndo->ndo_vflag <= 1)
1650 print_unknown_data(ndo, tptr, "\n\t ", tlen);
1651 return -1;
1652 }
1653 return 0;
1654 trunc:
1655 return -2;
1656 }
1657
1658 static int
1659 bgp_nlri_print(netdissect_options *ndo, uint16_t af, uint8_t safi,
1660 const u_char *tptr, u_int len,
1661 char *buf, size_t buflen,
1662 int add_path4, int add_path6)
1663 {
1664 int advance;
1665 u_int path_id = 0;
1666
1667 switch (af<<8 | safi) {
1668 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1669 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1670 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1671 if (add_path4) {
1672 path_id = GET_BE_U_4(tptr);
1673 tptr += 4;
1674 }
1675 advance = decode_prefix4(ndo, tptr, len, buf, buflen);
1676 if (advance == -1)
1677 ND_PRINT("\n\t (illegal prefix length)");
1678 else if (advance == -2)
1679 goto trunc;
1680 else if (advance == -3)
1681 break; /* bytes left, but not enough */
1682 else
1683 ND_PRINT("\n\t %s", buf);
1684 if (add_path4) {
1685 ND_PRINT(" Path Id: %u", path_id);
1686 advance += 4;
1687 }
1688 break;
1689 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1690 advance = decode_labeled_prefix4(ndo, tptr, len, buf, buflen);
1691 if (advance == -1)
1692 ND_PRINT("\n\t (illegal prefix length)");
1693 else if (advance == -2)
1694 goto trunc;
1695 else if (advance == -3)
1696 break; /* bytes left, but not enough */
1697 else
1698 ND_PRINT("\n\t %s", buf);
1699 break;
1700 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1701 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1702 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1703 advance = decode_labeled_vpn_prefix4(ndo, tptr, buf, buflen);
1704 if (advance == -1)
1705 ND_PRINT("\n\t (illegal prefix length)");
1706 else if (advance == -2)
1707 goto trunc;
1708 else
1709 ND_PRINT("\n\t %s", buf);
1710 break;
1711 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1712 advance = decode_rt_routing_info(ndo, tptr);
1713 if (advance == -2)
1714 goto trunc;
1715 break;
1716 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN): /* fall through */
1717 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST_VPN):
1718 advance = decode_multicast_vpn(ndo, tptr, buf, buflen);
1719 if (advance == -1)
1720 ND_PRINT("\n\t (illegal prefix length)");
1721 else if (advance == -2)
1722 goto trunc;
1723 else
1724 ND_PRINT("\n\t %s", buf);
1725 break;
1726
1727 case (AFNUM_INET<<8 | SAFNUM_MDT):
1728 advance = decode_mdt_vpn_nlri(ndo, tptr, buf, buflen);
1729 if (advance == -1)
1730 ND_PRINT("\n\t (illegal prefix length)");
1731 else if (advance == -2)
1732 goto trunc;
1733 else
1734 ND_PRINT("\n\t %s", buf);
1735 break;
1736 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1737 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1738 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1739 if (add_path6) {
1740 path_id = GET_BE_U_4(tptr);
1741 tptr += 4;
1742 }
1743 advance = decode_prefix6(ndo, tptr, len, buf, buflen);
1744 if (advance == -1)
1745 ND_PRINT("\n\t (illegal prefix length)");
1746 else if (advance == -2)
1747 goto trunc;
1748 else if (advance == -3)
1749 break; /* bytes left, but not enough */
1750 else
1751 ND_PRINT("\n\t %s", buf);
1752 if (add_path6) {
1753 ND_PRINT(" Path Id: %u", path_id);
1754 advance += 4;
1755 }
1756 break;
1757 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1758 advance = decode_labeled_prefix6(ndo, tptr, len, buf, buflen);
1759 if (advance == -1)
1760 ND_PRINT("\n\t (illegal prefix length)");
1761 else if (advance == -2)
1762 goto trunc;
1763 else if (advance == -3)
1764 break; /* bytes left, but not enough */
1765 else
1766 ND_PRINT("\n\t %s", buf);
1767 break;
1768 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1769 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1770 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1771 advance = decode_labeled_vpn_prefix6(ndo, tptr, buf, buflen);
1772 if (advance == -1)
1773 ND_PRINT("\n\t (illegal prefix length)");
1774 else if (advance == -2)
1775 goto trunc;
1776 else
1777 ND_PRINT("\n\t %s", buf);
1778 break;
1779 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1780 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1781 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1782 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1783 advance = decode_labeled_vpn_l2(ndo, tptr, buf, buflen);
1784 if (advance == -1)
1785 ND_PRINT("\n\t (illegal length)");
1786 else if (advance == -2)
1787 goto trunc;
1788 else
1789 ND_PRINT("\n\t %s", buf);
1790 break;
1791 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1792 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1793 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1794 advance = decode_clnp_prefix(ndo, tptr, buf, buflen);
1795 if (advance == -1)
1796 ND_PRINT("\n\t (illegal prefix length)");
1797 else if (advance == -2)
1798 goto trunc;
1799 else
1800 ND_PRINT("\n\t %s", buf);
1801 break;
1802 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1803 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1804 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1805 advance = decode_labeled_vpn_clnp_prefix(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 default:
1814 /*
1815 * This should not happen, we should have been protected
1816 * by bgp_mp_af_print()'s return value.
1817 */
1818 ND_PRINT("\n\t ERROR: no AFI %u / SAFI %u decoder", af, safi);
1819 advance = -4;
1820 break;
1821 }
1822 return advance;
1823 trunc: /* we rely on the caller to recognize -2 return value */
1824 return -2;
1825 }
1826
1827 static int
1828 bgp_attr_print(netdissect_options *ndo,
1829 uint8_t atype, const u_char *pptr, u_int len,
1830 const unsigned attr_set_level)
1831 {
1832 u_int i;
1833 uint16_t af;
1834 uint8_t safi, snpa, nhlen;
1835 int advance;
1836 u_int tlen;
1837 const u_char *tptr;
1838 char buf[MAXHOSTNAMELEN + 100];
1839 u_int as_size;
1840 int add_path4, add_path6;
1841 int ret;
1842
1843 tptr = pptr;
1844 tlen = len;
1845
1846 switch (atype) {
1847 case BGPTYPE_ORIGIN:
1848 if (len != 1)
1849 ND_PRINT("invalid len");
1850 else {
1851 ND_TCHECK_1(tptr);
1852 ND_PRINT("%s", tok2str(bgp_origin_values,
1853 "Unknown Origin Typecode",
1854 GET_U_1(tptr)));
1855 }
1856 break;
1857
1858 /*
1859 * Process AS4 byte path and AS2 byte path attributes here.
1860 */
1861 case BGPTYPE_AS4_PATH:
1862 case BGPTYPE_AS_PATH:
1863 if (len % 2) {
1864 ND_PRINT("invalid len");
1865 break;
1866 }
1867 if (!len) {
1868 ND_PRINT("empty");
1869 break;
1870 }
1871
1872 /*
1873 * BGP updates exchanged between New speakers that support 4
1874 * byte AS, ASs are always encoded in 4 bytes. There is no
1875 * definitive way to find this, just by the packet's
1876 * contents. So, check for packet's TLV's sanity assuming
1877 * 2 bytes first, and it does not pass, assume that ASs are
1878 * encoded in 4 bytes format and move on.
1879 */
1880 as_size = bgp_attr_get_as_size(ndo, atype, pptr, len);
1881
1882 while (tptr < pptr + len) {
1883 ND_TCHECK_1(tptr);
1884 ND_PRINT("%s", tok2str(bgp_as_path_segment_open_values,
1885 "?", GET_U_1(tptr)));
1886 ND_TCHECK_1(tptr + 1);
1887 for (i = 0; i < GET_U_1(tptr + 1) * as_size; i += as_size) {
1888 ND_TCHECK_LEN(tptr + 2 + i, as_size);
1889 ND_PRINT("%s ",
1890 as_printf(ndo, astostr, sizeof(astostr),
1891 as_size == 2 ?
1892 GET_BE_U_2(tptr + i + 2) :
1893 GET_BE_U_4(tptr + i + 2)));
1894 }
1895 ND_TCHECK_1(tptr);
1896 ND_PRINT("%s", tok2str(bgp_as_path_segment_close_values,
1897 "?", GET_U_1(tptr)));
1898 ND_TCHECK_1(tptr + 1);
1899 tptr += 2 + GET_U_1(tptr + 1) * as_size;
1900 }
1901 break;
1902 case BGPTYPE_NEXT_HOP:
1903 if (len != 4)
1904 ND_PRINT("invalid len");
1905 else {
1906 ND_TCHECK_4(tptr);
1907 ND_PRINT("%s", ipaddr_string(ndo, tptr));
1908 }
1909 break;
1910 case BGPTYPE_MULTI_EXIT_DISC:
1911 case BGPTYPE_LOCAL_PREF:
1912 if (len != 4)
1913 ND_PRINT("invalid len");
1914 else {
1915 ND_TCHECK_4(tptr);
1916 ND_PRINT("%u", GET_BE_U_4(tptr));
1917 }
1918 break;
1919 case BGPTYPE_ATOMIC_AGGREGATE:
1920 if (len != 0)
1921 ND_PRINT("invalid len");
1922 break;
1923 case BGPTYPE_AGGREGATOR:
1924
1925 /*
1926 * Depending on the AS encoded is of 2 bytes or of 4 bytes,
1927 * the length of this PA can be either 6 bytes or 8 bytes.
1928 */
1929 if (len != 6 && len != 8) {
1930 ND_PRINT("invalid len");
1931 break;
1932 }
1933 ND_TCHECK_LEN(tptr, len);
1934 if (len == 6) {
1935 ND_PRINT(" AS #%s, origin %s",
1936 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(tptr)),
1937 ipaddr_string(ndo, tptr + 2));
1938 } else {
1939 ND_PRINT(" AS #%s, origin %s",
1940 as_printf(ndo, astostr, sizeof(astostr),
1941 GET_BE_U_4(tptr)), ipaddr_string(ndo, tptr + 4));
1942 }
1943 break;
1944 case BGPTYPE_AGGREGATOR4:
1945 if (len != 8) {
1946 ND_PRINT("invalid len");
1947 break;
1948 }
1949 ND_TCHECK_8(tptr);
1950 ND_PRINT(" AS #%s, origin %s",
1951 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)),
1952 ipaddr_string(ndo, tptr + 4));
1953 break;
1954 case BGPTYPE_COMMUNITIES:
1955 if (len % 4) {
1956 ND_PRINT("invalid len");
1957 break;
1958 }
1959 while (tlen != 0) {
1960 uint32_t comm;
1961 ND_TCHECK_4(tptr);
1962 if (tlen < 4)
1963 goto trunc;
1964 comm = GET_BE_U_4(tptr);
1965 switch (comm) {
1966 case BGP_COMMUNITY_NO_EXPORT:
1967 ND_PRINT(" NO_EXPORT");
1968 break;
1969 case BGP_COMMUNITY_NO_ADVERT:
1970 ND_PRINT(" NO_ADVERTISE");
1971 break;
1972 case BGP_COMMUNITY_NO_EXPORT_SUBCONFED:
1973 ND_PRINT(" NO_EXPORT_SUBCONFED");
1974 break;
1975 default:
1976 ND_PRINT("%u:%u%s",
1977 (comm >> 16) & 0xffff,
1978 comm & 0xffff,
1979 (tlen>4) ? ", " : "");
1980 break;
1981 }
1982 tlen -=4;
1983 tptr +=4;
1984 }
1985 break;
1986 case BGPTYPE_ORIGINATOR_ID:
1987 if (len != 4) {
1988 ND_PRINT("invalid len");
1989 break;
1990 }
1991 ND_TCHECK_4(tptr);
1992 ND_PRINT("%s",ipaddr_string(ndo, tptr));
1993 break;
1994 case BGPTYPE_CLUSTER_LIST:
1995 if (len % 4) {
1996 ND_PRINT("invalid len");
1997 break;
1998 }
1999 while (tlen != 0) {
2000 ND_TCHECK_4(tptr);
2001 if (tlen < 4)
2002 goto trunc;
2003 ND_PRINT("%s%s",
2004 ipaddr_string(ndo, tptr),
2005 (tlen>4) ? ", " : "");
2006 tlen -=4;
2007 tptr +=4;
2008 }
2009 break;
2010 case BGPTYPE_MP_REACH_NLRI:
2011 ND_TCHECK_3(tptr);
2012 if (tlen < 3)
2013 goto trunc;
2014 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2015 if (ret == -2)
2016 goto trunc;
2017 if (ret < 0)
2018 break;
2019
2020 tptr += 3;
2021 tlen -= 3;
2022
2023 ND_TCHECK_1(tptr);
2024 nhlen = GET_U_1(tptr);
2025 tptr++;
2026 tlen--;
2027
2028 if (nhlen) {
2029 u_int nnh = 0;
2030 uint8_t tnhlen = nhlen;
2031 if (tlen < tnhlen)
2032 goto trunc;
2033 ND_PRINT("\n\t nexthop: ");
2034 while (tnhlen != 0) {
2035 if (nnh++ > 0) {
2036 ND_PRINT(", " );
2037 }
2038 switch(af<<8 | safi) {
2039 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
2040 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
2041 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
2042 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
2043 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
2044 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
2045 case (AFNUM_INET<<8 | SAFNUM_MDT):
2046 if (tnhlen < sizeof(nd_ipv4)) {
2047 ND_PRINT("invalid len");
2048 tptr += tnhlen;
2049 tlen -= tnhlen;
2050 tnhlen = 0;
2051 } else {
2052 ND_TCHECK_LEN(tptr, sizeof(nd_ipv4));
2053 ND_PRINT("%s",ipaddr_string(ndo, tptr));
2054 tptr += sizeof(nd_ipv4);
2055 tnhlen -= sizeof(nd_ipv4);
2056 tlen -= sizeof(nd_ipv4);
2057 }
2058 break;
2059 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
2060 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
2061 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
2062 if (tnhlen < sizeof(nd_ipv4)+BGP_VPN_RD_LEN) {
2063 ND_PRINT("invalid len");
2064 tptr += tnhlen;
2065 tlen -= tnhlen;
2066 tnhlen = 0;
2067 } else {
2068 ND_TCHECK_LEN(tptr,
2069 sizeof(nd_ipv4) + BGP_VPN_RD_LEN);
2070 ND_PRINT("RD: %s, %s",
2071 bgp_vpn_rd_print(ndo, tptr),
2072 ipaddr_string(ndo, tptr+BGP_VPN_RD_LEN));
2073 tptr += (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2074 tlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2075 tnhlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2076 }
2077 break;
2078 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
2079 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
2080 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
2081 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
2082 if (tnhlen < sizeof(nd_ipv6)) {
2083 ND_PRINT("invalid len");
2084 tptr += tnhlen;
2085 tlen -= tnhlen;
2086 tnhlen = 0;
2087 } else {
2088 ND_TCHECK_LEN(tptr, sizeof(nd_ipv6));
2089 ND_PRINT("%s", ip6addr_string(ndo, tptr));
2090 tptr += sizeof(nd_ipv6);
2091 tlen -= sizeof(nd_ipv6);
2092 tnhlen -= sizeof(nd_ipv6);
2093 }
2094 break;
2095 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
2096 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
2097 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
2098 if (tnhlen < sizeof(nd_ipv6)+BGP_VPN_RD_LEN) {
2099 ND_PRINT("invalid len");
2100 tptr += tnhlen;
2101 tlen -= tnhlen;
2102 tnhlen = 0;
2103 } else {
2104 ND_TCHECK_LEN(tptr,
2105 sizeof(nd_ipv6) + BGP_VPN_RD_LEN);
2106 ND_PRINT("RD: %s, %s",
2107 bgp_vpn_rd_print(ndo, tptr),
2108 ip6addr_string(ndo, tptr+BGP_VPN_RD_LEN));
2109 tptr += (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2110 tlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2111 tnhlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2112 }
2113 break;
2114 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
2115 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
2116 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
2117 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
2118 if (tnhlen < sizeof(nd_ipv4)) {
2119 ND_PRINT("invalid len");
2120 tptr += tnhlen;
2121 tlen -= tnhlen;
2122 tnhlen = 0;
2123 } else {
2124 ND_TCHECK_LEN(tptr, sizeof(nd_ipv4));
2125 ND_PRINT("%s", ipaddr_string(ndo, tptr));
2126 tptr += (sizeof(nd_ipv4));
2127 tlen -= (sizeof(nd_ipv4));
2128 tnhlen -= (sizeof(nd_ipv4));
2129 }
2130 break;
2131 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
2132 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
2133 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
2134 ND_TCHECK_LEN(tptr, tnhlen);
2135 ND_PRINT("%s", isonsap_string(ndo, tptr, tnhlen));
2136 tptr += tnhlen;
2137 tlen -= tnhlen;
2138 tnhlen = 0;
2139 break;
2140
2141 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
2142 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
2143 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
2144 if (tnhlen < BGP_VPN_RD_LEN+1) {
2145 ND_PRINT("invalid len");
2146 tptr += tnhlen;
2147 tlen -= tnhlen;
2148 tnhlen = 0;
2149 } else {
2150 ND_TCHECK_LEN(tptr, tnhlen);
2151 ND_PRINT("RD: %s, %s",
2152 bgp_vpn_rd_print(ndo, tptr),
2153 isonsap_string(ndo, tptr+BGP_VPN_RD_LEN,tnhlen-BGP_VPN_RD_LEN));
2154 /* rfc986 mapped IPv4 address ? */
2155 if (GET_BE_U_4(tptr + BGP_VPN_RD_LEN) == 0x47000601)
2156 ND_PRINT(" = %s", ipaddr_string(ndo, tptr+BGP_VPN_RD_LEN+4));
2157 /* rfc1888 mapped IPv6 address ? */
2158 else if (GET_BE_U_3(tptr + BGP_VPN_RD_LEN) == 0x350000)
2159 ND_PRINT(" = %s", ip6addr_string(ndo, tptr+BGP_VPN_RD_LEN+3));
2160 tptr += tnhlen;
2161 tlen -= tnhlen;
2162 tnhlen = 0;
2163 }
2164 break;
2165 default:
2166 /*
2167 * bgp_mp_af_print() should have saved us from
2168 * an unsupported AFI/SAFI.
2169 */
2170 ND_PRINT("ERROR: no AFI %u/SAFI %u nexthop decoder", af, safi);
2171 tptr += tnhlen;
2172 tlen -= tnhlen;
2173 tnhlen = 0;
2174 goto done;
2175 break;
2176 }
2177 }
2178 }
2179 ND_PRINT(", nh-length: %u", nhlen);
2180
2181 /* As per RFC 2858; this is reserved in RFC 4760 */
2182 if (tlen < 1)
2183 goto trunc;
2184 ND_TCHECK_1(tptr);
2185 snpa = GET_U_1(tptr);
2186 tptr++;
2187 tlen--;
2188
2189 if (snpa) {
2190 ND_PRINT("\n\t %u SNPA", snpa);
2191 for (/*nothing*/; snpa != 0; snpa--) {
2192 uint8_t snpalen;
2193 if (tlen < 1)
2194 goto trunc;
2195 ND_TCHECK_1(tptr);
2196 snpalen = GET_U_1(tptr);
2197 ND_PRINT("\n\t %u bytes", snpalen);
2198 tptr++;
2199 tlen--;
2200 if (tlen < snpalen)
2201 goto trunc;
2202 tptr += snpalen;
2203 tlen -= snpalen;
2204 }
2205 } else {
2206 ND_PRINT(", no SNPA");
2207 }
2208
2209 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2210 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2211
2212 while (tptr < pptr + len) {
2213 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2214 add_path4, add_path6);
2215 if (advance == -2)
2216 goto trunc;
2217 if (advance < 0)
2218 break;
2219 tptr += advance;
2220 }
2221 break;
2222
2223 case BGPTYPE_MP_UNREACH_NLRI:
2224 ND_TCHECK_LEN(tptr, BGP_MP_NLRI_MINSIZE);
2225 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2226 if (ret == -2)
2227 goto trunc;
2228 if (ret < 0)
2229 break;
2230
2231 if (len == BGP_MP_NLRI_MINSIZE)
2232 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2233
2234 tptr += 3;
2235
2236 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2237 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2238
2239 while (tptr < pptr + len) {
2240 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2241 add_path4, add_path6);
2242 if (advance == -2)
2243 goto trunc;
2244 if (advance < 0)
2245 break;
2246 tptr += advance;
2247 }
2248 break;
2249 case BGPTYPE_EXTD_COMMUNITIES:
2250 if (len % 8) {
2251 ND_PRINT("invalid len");
2252 break;
2253 }
2254 while (tlen != 0) {
2255 uint16_t extd_comm;
2256
2257 ND_TCHECK_2(tptr);
2258 if (tlen < 2)
2259 goto trunc;
2260 extd_comm=GET_BE_U_2(tptr);
2261
2262 ND_PRINT("\n\t %s (0x%04x), Flags [%s]",
2263 tok2str(bgp_extd_comm_subtype_values,
2264 "unknown extd community typecode",
2265 extd_comm),
2266 extd_comm,
2267 bittok2str(bgp_extd_comm_flag_values, "none", extd_comm));
2268
2269 ND_TCHECK_8(tptr);
2270 if (tlen < 8)
2271 goto trunc;
2272 ND_PRINT(": ");
2273 bgp_extended_community_print(ndo, tptr);
2274 tlen -= 8;
2275 tptr += 8;
2276 }
2277 break;
2278
2279 case BGPTYPE_PMSI_TUNNEL:
2280 {
2281 uint8_t tunnel_type, flags;
2282
2283 ND_TCHECK_5(tptr);
2284 if (tlen < 5)
2285 goto trunc;
2286 flags = GET_U_1(tptr);
2287 tunnel_type = GET_U_1(tptr + 1);
2288 tlen = len;
2289
2290 ND_PRINT("\n\t Tunnel-type %s (%u), Flags [%s], MPLS Label %u",
2291 tok2str(bgp_pmsi_tunnel_values, "Unknown", tunnel_type),
2292 tunnel_type,
2293 bittok2str(bgp_pmsi_flag_values, "none", flags),
2294 GET_BE_U_3(tptr + 2)>>4);
2295
2296 tptr +=5;
2297 tlen -= 5;
2298
2299 switch (tunnel_type) {
2300 case BGP_PMSI_TUNNEL_PIM_SM: /* fall through */
2301 case BGP_PMSI_TUNNEL_PIM_BIDIR:
2302 ND_TCHECK_8(tptr);
2303 ND_PRINT("\n\t Sender %s, P-Group %s",
2304 ipaddr_string(ndo, tptr),
2305 ipaddr_string(ndo, tptr+4));
2306 break;
2307
2308 case BGP_PMSI_TUNNEL_PIM_SSM:
2309 ND_TCHECK_8(tptr);
2310 ND_PRINT("\n\t Root-Node %s, P-Group %s",
2311 ipaddr_string(ndo, tptr),
2312 ipaddr_string(ndo, tptr+4));
2313 break;
2314 case BGP_PMSI_TUNNEL_INGRESS:
2315 ND_TCHECK_4(tptr);
2316 ND_PRINT("\n\t Tunnel-Endpoint %s",
2317 ipaddr_string(ndo, tptr));
2318 break;
2319 case BGP_PMSI_TUNNEL_LDP_P2MP: /* fall through */
2320 case BGP_PMSI_TUNNEL_LDP_MP2MP:
2321 ND_TCHECK_8(tptr);
2322 ND_PRINT("\n\t Root-Node %s, LSP-ID 0x%08x",
2323 ipaddr_string(ndo, tptr),
2324 GET_BE_U_4(tptr + 4));
2325 break;
2326 case BGP_PMSI_TUNNEL_RSVP_P2MP:
2327 ND_TCHECK_8(tptr);
2328 ND_PRINT("\n\t Extended-Tunnel-ID %s, P2MP-ID 0x%08x",
2329 ipaddr_string(ndo, tptr),
2330 GET_BE_U_4(tptr + 4));
2331 break;
2332 default:
2333 if (ndo->ndo_vflag <= 1) {
2334 print_unknown_data(ndo, tptr, "\n\t ", tlen);
2335 }
2336 }
2337 break;
2338 }
2339 case BGPTYPE_AIGP:
2340 {
2341 uint8_t type;
2342 uint16_t length;
2343
2344 tlen = len;
2345
2346 while (tlen >= 3) {
2347
2348 ND_TCHECK_3(tptr);
2349
2350 type = GET_U_1(tptr);
2351 length = GET_BE_U_2(tptr + 1);
2352 tptr += 3;
2353 tlen -= 3;
2354
2355 ND_PRINT("\n\t %s TLV (%u), length %u",
2356 tok2str(bgp_aigp_values, "Unknown", type),
2357 type, length);
2358
2359 if (length < 3)
2360 goto trunc;
2361 length -= 3;
2362
2363 /*
2364 * Check if we can read the TLV data.
2365 */
2366 ND_TCHECK_LEN(tptr + 3, length);
2367 if (tlen < length)
2368 goto trunc;
2369
2370 switch (type) {
2371
2372 case BGP_AIGP_TLV:
2373 if (length < 8)
2374 goto trunc;
2375 ND_PRINT(", metric %" PRIu64,
2376 GET_BE_U_8(tptr));
2377 break;
2378
2379 default:
2380 if (ndo->ndo_vflag <= 1) {
2381 print_unknown_data(ndo, tptr,"\n\t ", length);
2382 }
2383 }
2384
2385 tptr += length;
2386 tlen -= length;
2387 }
2388 break;
2389 }
2390 case BGPTYPE_ATTR_SET:
2391 ND_TCHECK_4(tptr);
2392 if (len < 4)
2393 goto trunc;
2394 ND_PRINT("\n\t Origin AS: %s",
2395 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)));
2396 tptr += 4;
2397 len -= 4;
2398
2399 while (len) {
2400 u_int aflags, alenlen, alen;
2401
2402 ND_TCHECK_2(tptr);
2403 if (len < 2) {
2404 ND_PRINT(" [path attr too short]");
2405 tptr += len;
2406 break;
2407 }
2408 aflags = GET_U_1(tptr);
2409 atype = GET_U_1(tptr + 1);
2410 tptr += 2;
2411 len -= 2;
2412 alenlen = bgp_attr_lenlen(aflags, tptr);
2413 ND_TCHECK_LEN(tptr, alenlen);
2414 if (len < alenlen) {
2415 ND_PRINT(" [path attr too short]");
2416 tptr += len;
2417 break;
2418 }
2419 alen = bgp_attr_len(aflags, tptr);
2420 tptr += alenlen;
2421 len -= alenlen;
2422
2423 ND_PRINT("\n\t %s (%u), length: %u",
2424 tok2str(bgp_attr_values,
2425 "Unknown Attribute", atype),
2426 atype,
2427 alen);
2428
2429 if (aflags) {
2430 ND_PRINT(", Flags [%s%s%s%s",
2431 aflags & 0x80 ? "O" : "",
2432 aflags & 0x40 ? "T" : "",
2433 aflags & 0x20 ? "P" : "",
2434 aflags & 0x10 ? "E" : "");
2435 if (aflags & 0xf)
2436 ND_PRINT("+%x", aflags & 0xf);
2437 ND_PRINT("]");
2438 }
2439 ND_PRINT(": ");
2440 if (len < alen) {
2441 ND_PRINT(" [path attr too short]");
2442 tptr += len;
2443 break;
2444 }
2445 /*
2446 * The protocol encoding per se allows ATTR_SET to be nested
2447 * as many times as the message can accommodate. This printer
2448 * used to be able to recurse into ATTR_SET contents until the
2449 * stack exhaustion, but now there is a limit on that (if live
2450 * protocol exchange goes that many levels deep, something is
2451 * probably wrong anyway). Feel free to refine this value if
2452 * you can find the spec with respective normative text.
2453 */
2454 if (attr_set_level == 10)
2455 ND_PRINT("(too many nested levels, not recursing)");
2456 else if (!bgp_attr_print(ndo, atype, tptr, alen, attr_set_level + 1))
2457 return 0;
2458 tptr += alen;
2459 len -= alen;
2460 }
2461 break;
2462
2463 case BGPTYPE_LARGE_COMMUNITY:
2464 if (len == 0 || len % 12) {
2465 ND_PRINT("invalid len");
2466 break;
2467 }
2468 ND_PRINT("\n\t ");
2469 while (len != 0) {
2470 ND_TCHECK_LEN(tptr, 12);
2471 ND_PRINT("%u:%u:%u%s",
2472 GET_BE_U_4(tptr),
2473 GET_BE_U_4(tptr + 4),
2474 GET_BE_U_4(tptr + 8),
2475 (len > 12) ? ", " : "");
2476 tptr += 12;
2477 /*
2478 * len will always be a multiple of 12, as per the above,
2479 * so this will never underflow.
2480 */
2481 len -= 12;
2482 }
2483 break;
2484 default:
2485 ND_TCHECK_LEN(pptr, len);
2486 ND_PRINT("\n\t no Attribute %u decoder", atype); /* we have no decoder for the attribute */
2487 if (ndo->ndo_vflag <= 1)
2488 print_unknown_data(ndo, pptr, "\n\t ", len);
2489 break;
2490 }
2491 done:
2492 if (ndo->ndo_vflag > 1 && len) { /* omit zero length attributes*/
2493 ND_TCHECK_LEN(pptr, len);
2494 print_unknown_data(ndo, pptr, "\n\t ", len);
2495 }
2496 return 1;
2497
2498 trunc:
2499 return 0;
2500 }
2501
2502 static void
2503 bgp_capabilities_print(netdissect_options *ndo,
2504 const u_char *opt, u_int caps_len)
2505 {
2506 u_int cap_type, cap_len, tcap_len, cap_offset;
2507 u_int i = 0;
2508
2509 while (i < caps_len) {
2510 ND_TCHECK_LEN(opt + i, BGP_CAP_HEADER_SIZE);
2511 cap_type=GET_U_1(opt + i);
2512 cap_len=GET_U_1(opt + i + 1);
2513 ND_PRINT("\n\t %s (%u), length: %u",
2514 tok2str(bgp_capcode_values, "Unknown", cap_type),
2515 cap_type,
2516 cap_len);
2517 ND_TCHECK_LEN(opt + 2 + i, cap_len);
2518 switch (cap_type) {
2519 case BGP_CAPCODE_MP:
2520 /* AFI (16 bits), Reserved (8 bits), SAFI (8 bits) */
2521 if (cap_len < 4) {
2522 ND_PRINT(" (too short, < 4)");
2523 return;
2524 }
2525 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u)",
2526 tok2str(af_values, "Unknown", GET_BE_U_2(opt + i + 2)),
2527 GET_BE_U_2(opt + i + 2),
2528 tok2str(bgp_safi_values, "Unknown", GET_U_1(opt + i + 5)),
2529 GET_U_1(opt + i + 5));
2530 break;
2531 case BGP_CAPCODE_ML:
2532 cap_offset = 2;
2533 tcap_len = cap_len;
2534 while (tcap_len >= 4) {
2535 ND_PRINT( "\n\t\tAFI %s (%u), SAFI %s (%u), Count: %u",
2536 tok2str(af_values, "Unknown",
2537 GET_BE_U_2(opt + i + cap_offset)),
2538 GET_BE_U_2(opt + i + cap_offset),
2539 tok2str(bgp_safi_values, "Unknown",
2540 GET_U_1(opt + i + cap_offset + 2)),
2541 GET_U_1(opt + i + cap_offset + 2),
2542 GET_U_1(opt + i + cap_offset + 3));
2543 tcap_len -= 4;
2544 cap_offset += 4;
2545 }
2546 break;
2547 case BGP_CAPCODE_RESTART:
2548 /* Restart Flags (4 bits), Restart Time in seconds (12 bits) */
2549 if (cap_len < 2) {
2550 ND_PRINT(" (too short, < 2)");
2551 return;
2552 }
2553 tcap_len=cap_len;
2554 ND_PRINT("\n\t\tRestart Flags: [%s], Restart Time %us",
2555 ((GET_U_1(opt + i + 2))&0x80) ? "R" : "none",
2556 GET_BE_U_2(opt + i + 2)&0xfff);
2557 tcap_len-=2;
2558 cap_offset=4;
2559 while(tcap_len>=4) {
2560 ND_PRINT("\n\t\t AFI %s (%u), SAFI %s (%u), Forwarding state preserved: %s",
2561 tok2str(af_values,"Unknown",
2562 GET_BE_U_2(opt + i + cap_offset)),
2563 GET_BE_U_2(opt + i + cap_offset),
2564 tok2str(bgp_safi_values,"Unknown",
2565 GET_U_1(opt + i + cap_offset + 2)),
2566 GET_U_1(opt + (i + cap_offset + 2)),
2567 ((GET_U_1(opt + (i + cap_offset + 3)))&0x80) ? "yes" : "no" );
2568 tcap_len -= 4;
2569 cap_offset += 4;
2570 }
2571 break;
2572 case BGP_CAPCODE_RR:
2573 case BGP_CAPCODE_LLGR:
2574 case BGP_CAPCODE_RR_CISCO:
2575 break;
2576 case BGP_CAPCODE_AS_NEW:
2577 /*
2578 * Extract the 4 byte AS number encoded.
2579 */
2580 if (cap_len < 4) {
2581 ND_PRINT(" (too short, < 4)");
2582 return;
2583 }
2584 ND_PRINT("\n\t\t 4 Byte AS %s",
2585 as_printf(ndo, astostr, sizeof(astostr),
2586 GET_BE_U_4(opt + i + 2)));
2587 break;
2588 case BGP_CAPCODE_ADD_PATH:
2589 if (cap_len == 0) {
2590 ND_PRINT(" (bogus)"); /* length */
2591 break;
2592 }
2593 tcap_len=cap_len;
2594 cap_offset=2;
2595 while (tcap_len != 0) {
2596 if (tcap_len < 4) {
2597 nd_print_invalid(ndo);
2598 break;
2599 }
2600 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u), Send/Receive: %s",
2601 tok2str(af_values,"Unknown",GET_BE_U_2(opt + i + cap_offset)),
2602 GET_BE_U_2(opt + i + cap_offset),
2603 tok2str(bgp_safi_values,"Unknown",GET_U_1(opt + i + cap_offset + 2)),
2604 GET_U_1(opt + (i + cap_offset + 2)),
2605 tok2str(bgp_add_path_recvsend,"Bogus (0x%02x)",GET_U_1(opt + i + cap_offset + 3))
2606 );
2607 tcap_len -= 4;
2608 cap_offset += 4;
2609 }
2610 break;
2611 default:
2612 ND_PRINT("\n\t\tno decoder for Capability %u",
2613 cap_type);
2614 if (ndo->ndo_vflag <= 1)
2615 print_unknown_data(ndo, opt + i + 2, "\n\t\t",
2616 cap_len);
2617 break;
2618 }
2619 if (ndo->ndo_vflag > 1 && cap_len != 0) {
2620 print_unknown_data(ndo, opt + i + 2, "\n\t\t", cap_len);
2621 }
2622 i += BGP_CAP_HEADER_SIZE + cap_len;
2623 }
2624 return;
2625
2626 trunc:
2627 nd_print_trunc(ndo);
2628 }
2629
2630 static void
2631 bgp_open_print(netdissect_options *ndo,
2632 const u_char *dat, u_int length)
2633 {
2634 const struct bgp_open *bgp_open_header;
2635 u_int optslen;
2636 const struct bgp_opt *bgpopt;
2637 const u_char *opt;
2638 u_int i;
2639
2640 ND_TCHECK_LEN(dat, BGP_OPEN_SIZE);
2641 if (length < BGP_OPEN_SIZE)
2642 goto trunc;
2643
2644 bgp_open_header = (const struct bgp_open *)dat;
2645
2646 ND_PRINT("\n\t Version %u, ",
2647 GET_U_1(bgp_open_header->bgpo_version));
2648 ND_PRINT("my AS %s, ",
2649 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(bgp_open_header->bgpo_myas)));
2650 ND_PRINT("Holdtime %us, ",
2651 GET_BE_U_2(bgp_open_header->bgpo_holdtime));
2652 ND_PRINT("ID %s", ipaddr_string(ndo, bgp_open_header->bgpo_id));
2653 optslen = GET_U_1(bgp_open_header->bgpo_optlen);
2654 ND_PRINT("\n\t Optional parameters, length: %u", optslen);
2655
2656 opt = dat + BGP_OPEN_SIZE;
2657 length -= BGP_OPEN_SIZE;
2658
2659 i = 0;
2660 while (i < optslen) {
2661 uint8_t opt_type, opt_len;
2662
2663 ND_TCHECK_LEN(opt + i, BGP_OPT_SIZE);
2664 if (length < BGP_OPT_SIZE + i)
2665 goto trunc;
2666 bgpopt = (const struct bgp_opt *)(opt + i);
2667 opt_type = GET_U_1(bgpopt->bgpopt_type);
2668 opt_len = GET_U_1(bgpopt->bgpopt_len);
2669 if (BGP_OPT_SIZE + i + opt_len > optslen) {
2670 ND_PRINT("\n\t Option %u, length: %u, goes past the end of the options",
2671 opt_type, opt_len);
2672 break;
2673 }
2674
2675 ND_PRINT("\n\t Option %s (%u), length: %u",
2676 tok2str(bgp_opt_values,"Unknown",opt_type),
2677 opt_type,
2678 opt_len);
2679
2680 /* now let's decode the options we know*/
2681 switch(opt_type) {
2682
2683 case BGP_OPT_CAP:
2684 bgp_capabilities_print(ndo, opt + BGP_OPT_SIZE + i,
2685 opt_len);
2686 break;
2687
2688 case BGP_OPT_AUTH:
2689 default:
2690 ND_PRINT("\n\t no decoder for option %u",
2691 opt_type);
2692 break;
2693 }
2694 i += BGP_OPT_SIZE + opt_len;
2695 }
2696 return;
2697 trunc:
2698 nd_print_trunc(ndo);
2699 }
2700
2701 static void
2702 bgp_update_print(netdissect_options *ndo,
2703 const u_char *dat, u_int length)
2704 {
2705 const u_char *p;
2706 u_int withdrawn_routes_len;
2707 char buf[MAXHOSTNAMELEN + 100];
2708 int wpfx;
2709 u_int len;
2710 int i;
2711 int add_path;
2712 u_int path_id = 0;
2713
2714 ND_TCHECK_LEN(dat, BGP_SIZE);
2715 if (length < BGP_SIZE)
2716 goto trunc;
2717 p = dat + BGP_SIZE;
2718 length -= BGP_SIZE;
2719
2720 /* Unfeasible routes */
2721 ND_TCHECK_2(p);
2722 if (length < 2)
2723 goto trunc;
2724 withdrawn_routes_len = GET_BE_U_2(p);
2725 p += 2;
2726 length -= 2;
2727 if (withdrawn_routes_len > 1) {
2728 /*
2729 * Without keeping state from the original NLRI message,
2730 * it's not possible to tell if this a v4 or v6 route,
2731 * so only try to decode it if we're not v6 enabled.
2732 */
2733 ND_TCHECK_LEN(p, withdrawn_routes_len);
2734 if (length < withdrawn_routes_len)
2735 goto trunc;
2736 ND_PRINT("\n\t Withdrawn routes:");
2737 add_path = check_add_path(ndo, p, withdrawn_routes_len, 32);
2738 while (withdrawn_routes_len != 0) {
2739 if (add_path) {
2740 if (withdrawn_routes_len < 4) {
2741 p += withdrawn_routes_len;
2742 length -= withdrawn_routes_len;
2743 break;
2744 }
2745 path_id = GET_BE_U_4(p);
2746 p += 4;
2747 length -= 4;
2748 withdrawn_routes_len -= 4;
2749 }
2750 wpfx = decode_prefix4(ndo, p, withdrawn_routes_len, buf, sizeof(buf));
2751 if (wpfx == -1) {
2752 ND_PRINT("\n\t (illegal prefix length)");
2753 break;
2754 } else if (wpfx == -2)
2755 goto trunc;
2756 else if (wpfx == -3)
2757 goto trunc; /* bytes left, but not enough */
2758 else {
2759 ND_PRINT("\n\t %s", buf);
2760 if (add_path) {
2761 ND_PRINT(" Path Id: %u", path_id);
2762 }
2763 p += wpfx;
2764 length -= wpfx;
2765 withdrawn_routes_len -= wpfx;
2766 }
2767 }
2768 } else {
2769 ND_TCHECK_LEN(p, withdrawn_routes_len);
2770 if (length < withdrawn_routes_len)
2771 goto trunc;
2772 p += withdrawn_routes_len;
2773 length -= withdrawn_routes_len;
2774 }
2775
2776 ND_TCHECK_2(p);
2777 if (length < 2)
2778 goto trunc;
2779 len = GET_BE_U_2(p);
2780 p += 2;
2781 length -= 2;
2782
2783 if (withdrawn_routes_len == 0 && len == 0 && length == 0) {
2784 /* No withdrawn routes, no path attributes, no NLRI */
2785 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2786 return;
2787 }
2788
2789 if (len) {
2790 /* do something more useful!*/
2791 while (len) {
2792 uint8_t aflags, atype, alenlen;
2793 uint16_t alen;
2794
2795 ND_TCHECK_2(p);
2796 if (length < 2)
2797 goto trunc;
2798 if (len < 2) {
2799 ND_PRINT("\n\t [path attrs too short]");
2800 p += len;
2801 length -= len;
2802 break;
2803 }
2804 aflags = GET_U_1(p);
2805 atype = GET_U_1(p + 1);
2806 p += 2;
2807 len -= 2;
2808 length -= 2;
2809 alenlen = bgp_attr_lenlen(aflags, p);
2810 ND_TCHECK_LEN(p, alenlen);
2811 if (length < alenlen)
2812 goto trunc;
2813 if (len < alenlen) {
2814 ND_PRINT("\n\t [path attrs too short]");
2815 p += len;
2816 length -= len;
2817 break;
2818 }
2819 alen = bgp_attr_len(aflags, p);
2820 p += alenlen;
2821 len -= alenlen;
2822 length -= alenlen;
2823
2824 ND_PRINT("\n\t %s (%u), length: %u",
2825 tok2str(bgp_attr_values, "Unknown Attribute", atype),
2826 atype,
2827 alen);
2828
2829 if (aflags) {
2830 ND_PRINT(", Flags [%s%s%s%s",
2831 aflags & 0x80 ? "O" : "",
2832 aflags & 0x40 ? "T" : "",
2833 aflags & 0x20 ? "P" : "",
2834 aflags & 0x10 ? "E" : "");
2835 if (aflags & 0xf)
2836 ND_PRINT("+%x", aflags & 0xf);
2837 ND_PRINT("]: ");
2838 }
2839 if (len < alen) {
2840 ND_PRINT(" [path attrs too short]");
2841 p += len;
2842 length -= len;
2843 break;
2844 }
2845 if (length < alen)
2846 goto trunc;
2847 if (!bgp_attr_print(ndo, atype, p, alen, 0))
2848 goto trunc;
2849 p += alen;
2850 len -= alen;
2851 length -= alen;
2852 }
2853 }
2854
2855 if (length) {
2856 add_path = check_add_path(ndo, p, length, 32);
2857 ND_PRINT("\n\t Updated routes:");
2858 while (length != 0) {
2859 if (add_path) {
2860 ND_TCHECK_4(p);
2861 if (length < 4)
2862 goto trunc;
2863 path_id = GET_BE_U_4(p);
2864 p += 4;
2865 length -= 4;
2866 }
2867 i = decode_prefix4(ndo, p, length, buf, sizeof(buf));
2868 if (i == -1) {
2869 ND_PRINT("\n\t (illegal prefix length)");
2870 break;
2871 } else if (i == -2)
2872 goto trunc;
2873 else if (i == -3)
2874 goto trunc; /* bytes left, but not enough */
2875 else {
2876 ND_PRINT("\n\t %s", buf);
2877 if (add_path) {
2878 ND_PRINT(" Path Id: %u", path_id);
2879 }
2880 p += i;
2881 length -= i;
2882 }
2883 }
2884 }
2885 return;
2886 trunc:
2887 nd_print_trunc(ndo);
2888 }
2889
2890 static void
2891 bgp_notification_print(netdissect_options *ndo,
2892 const u_char *dat, u_int length)
2893 {
2894 const struct bgp_notification *bgp_notification_header;
2895 const u_char *tptr;
2896 uint8_t bgpn_major, bgpn_minor;
2897 uint8_t shutdown_comm_length;
2898 uint8_t remainder_offset;
2899
2900 ND_TCHECK_LEN(dat, BGP_NOTIFICATION_SIZE);
2901 if (length<BGP_NOTIFICATION_SIZE)
2902 return;
2903
2904 bgp_notification_header = (const struct bgp_notification *)dat;
2905 bgpn_major = GET_U_1(bgp_notification_header->bgpn_major);
2906 bgpn_minor = GET_U_1(bgp_notification_header->bgpn_minor);
2907
2908 ND_PRINT(", %s (%u)",
2909 tok2str(bgp_notify_major_values, "Unknown Error",
2910 bgpn_major),
2911 bgpn_major);
2912
2913 switch (bgpn_major) {
2914
2915 case BGP_NOTIFY_MAJOR_MSG:
2916 ND_PRINT(", subcode %s (%u)",
2917 tok2str(bgp_notify_minor_msg_values, "Unknown",
2918 bgpn_minor),
2919 bgpn_minor);
2920 break;
2921 case BGP_NOTIFY_MAJOR_OPEN:
2922 ND_PRINT(", subcode %s (%u)",
2923 tok2str(bgp_notify_minor_open_values, "Unknown",
2924 bgpn_minor),
2925 bgpn_minor);
2926 break;
2927 case BGP_NOTIFY_MAJOR_UPDATE:
2928 ND_PRINT(", subcode %s (%u)",
2929 tok2str(bgp_notify_minor_update_values, "Unknown",
2930 bgpn_minor),
2931 bgpn_minor);
2932 break;
2933 case BGP_NOTIFY_MAJOR_FSM:
2934 ND_PRINT(" subcode %s (%u)",
2935 tok2str(bgp_notify_minor_fsm_values, "Unknown",
2936 bgpn_minor),
2937 bgpn_minor);
2938 break;
2939 case BGP_NOTIFY_MAJOR_CAP:
2940 ND_PRINT(" subcode %s (%u)",
2941 tok2str(bgp_notify_minor_cap_values, "Unknown",
2942 bgpn_minor),
2943 bgpn_minor);
2944 break;
2945 case BGP_NOTIFY_MAJOR_CEASE:
2946 ND_PRINT(", subcode %s (%u)",
2947 tok2str(bgp_notify_minor_cease_values, "Unknown",
2948 bgpn_minor),
2949 bgpn_minor);
2950
2951 /* draft-ietf-idr-cease-subcode-02 mentions optionally 7 bytes
2952 * for the maxprefix subtype, which may contain AFI, SAFI and MAXPREFIXES
2953 */
2954 if(bgpn_minor == BGP_NOTIFY_MINOR_CEASE_MAXPRFX && length >= BGP_NOTIFICATION_SIZE + 7) {
2955 tptr = dat + BGP_NOTIFICATION_SIZE;
2956 ND_TCHECK_7(tptr);
2957 ND_PRINT(", AFI %s (%u), SAFI %s (%u), Max Prefixes: %u",
2958 tok2str(af_values, "Unknown", GET_BE_U_2(tptr)),
2959 GET_BE_U_2(tptr),
2960 tok2str(bgp_safi_values, "Unknown", GET_U_1((tptr + 2))),
2961 GET_U_1((tptr + 2)),
2962 GET_BE_U_4(tptr + 3));
2963 }
2964 /*
2965 * draft-ietf-idr-shutdown describes a method to send a communication
2966 * intended for human consumption regarding the Administrative Shutdown
2967 */
2968 if ((bgpn_minor == BGP_NOTIFY_MINOR_CEASE_SHUT ||
2969 bgpn_minor == BGP_NOTIFY_MINOR_CEASE_RESET) &&
2970 length >= BGP_NOTIFICATION_SIZE + 1) {
2971 tptr = dat + BGP_NOTIFICATION_SIZE;
2972 ND_TCHECK_1(tptr);
2973 shutdown_comm_length = GET_U_1(tptr);
2974 remainder_offset = 0;
2975 /* garbage, hexdump it all */
2976 if (shutdown_comm_length > BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN ||
2977 shutdown_comm_length > length - (BGP_NOTIFICATION_SIZE + 1)) {
2978 ND_PRINT(", invalid Shutdown Communication length");
2979 }
2980 else if (shutdown_comm_length == 0) {
2981 ND_PRINT(", empty Shutdown Communication");
2982 remainder_offset += 1;
2983 }
2984 /* a proper shutdown communication */
2985 else {
2986 ND_TCHECK_LEN(tptr + 1, shutdown_comm_length);
2987 ND_PRINT(", Shutdown Communication (length: %u): \"", shutdown_comm_length);
2988 (void)nd_printn(ndo, tptr+1, shutdown_comm_length, NULL);
2989 ND_PRINT("\"");
2990 remainder_offset += shutdown_comm_length + 1;
2991 }
2992 /* if there is trailing data, hexdump it */
2993 if(length - (remainder_offset + BGP_NOTIFICATION_SIZE) > 0) {
2994 ND_PRINT(", Data: (length: %u)", length - (remainder_offset + BGP_NOTIFICATION_SIZE));
2995 hex_print(ndo, "\n\t\t", tptr + remainder_offset, length - (remainder_offset + BGP_NOTIFICATION_SIZE));
2996 }
2997 }
2998 break;
2999 default:
3000 break;
3001 }
3002
3003 return;
3004 trunc:
3005 nd_print_trunc(ndo);
3006 }
3007
3008 static void
3009 bgp_route_refresh_print(netdissect_options *ndo,
3010 const u_char *pptr, u_int len)
3011 {
3012 const struct bgp_route_refresh *bgp_route_refresh_header;
3013
3014 ND_TCHECK_LEN(pptr, BGP_ROUTE_REFRESH_SIZE);
3015
3016 /* some little sanity checking */
3017 if (len<BGP_ROUTE_REFRESH_SIZE)
3018 return;
3019
3020 bgp_route_refresh_header = (const struct bgp_route_refresh *)pptr;
3021
3022 ND_PRINT("\n\t AFI %s (%u), SAFI %s (%u)",
3023 tok2str(af_values,"Unknown",
3024 GET_BE_U_2(bgp_route_refresh_header->afi)),
3025 GET_BE_U_2(bgp_route_refresh_header->afi),
3026 tok2str(bgp_safi_values,"Unknown",
3027 GET_U_1(bgp_route_refresh_header->safi)),
3028 GET_U_1(bgp_route_refresh_header->safi));
3029
3030 if (ndo->ndo_vflag > 1) {
3031 ND_TCHECK_LEN(pptr, len);
3032 print_unknown_data(ndo, pptr, "\n\t ", len);
3033 }
3034
3035 return;
3036 trunc:
3037 nd_print_trunc(ndo);
3038 }
3039
3040 static int
3041 bgp_pdu_print(netdissect_options *ndo,
3042 const u_char *dat, u_int length)
3043 {
3044 const struct bgp *bgp_header;
3045 uint8_t bgp_type;
3046
3047 ND_TCHECK_LEN(dat, BGP_SIZE);
3048 bgp_header = (const struct bgp *)dat;
3049 bgp_type = GET_U_1(bgp_header->bgp_type);
3050
3051 ND_PRINT("\n\t%s Message (%u), length: %u",
3052 tok2str(bgp_msg_values, "Unknown", bgp_type),
3053 bgp_type,
3054 length);
3055
3056 switch (bgp_type) {
3057 case BGP_OPEN:
3058 bgp_open_print(ndo, dat, length);
3059 break;
3060 case BGP_UPDATE:
3061 bgp_update_print(ndo, dat, length);
3062 break;
3063 case BGP_NOTIFICATION:
3064 bgp_notification_print(ndo, dat, length);
3065 break;
3066 case BGP_KEEPALIVE:
3067 break;
3068 case BGP_ROUTE_REFRESH:
3069 bgp_route_refresh_print(ndo, dat, length);
3070 break;
3071 default:
3072 /* we have no decoder for the BGP message */
3073 ND_TCHECK_LEN(dat, length);
3074 ND_PRINT("\n\t no Message %u decoder", bgp_type);
3075 print_unknown_data(ndo, dat, "\n\t ", length);
3076 break;
3077 }
3078 return 1;
3079 trunc:
3080 nd_print_trunc(ndo);
3081 return 0;
3082 }
3083
3084 void
3085 bgp_print(netdissect_options *ndo,
3086 const u_char *dat, u_int length _U_)
3087 {
3088 const u_char *p;
3089 const u_char *ep = ndo->ndo_snapend;
3090 const u_char *start;
3091 const u_char marker[] = {
3092 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3093 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3094 };
3095 const struct bgp *bgp_header;
3096 uint16_t hlen;
3097
3098 ndo->ndo_protocol = "bgp";
3099 ND_PRINT(": BGP");
3100
3101 if (ndo->ndo_vflag < 1) /* lets be less chatty */
3102 return;
3103
3104 p = dat;
3105 start = p;
3106 while (p < ep) {
3107 if (!ND_TTEST_1(p))
3108 break;
3109 if (GET_U_1(p) != 0xff) {
3110 p++;
3111 continue;
3112 }
3113
3114 if (!ND_TTEST_LEN(p, sizeof(marker)))
3115 break;
3116 if (memcmp(p, marker, sizeof(marker)) != 0) {
3117 p++;
3118 continue;
3119 }
3120
3121 /* found BGP header */
3122 ND_TCHECK_LEN(p, BGP_SIZE);
3123 bgp_header = (const struct bgp *)p;
3124
3125 if (start != p)
3126 nd_print_trunc(ndo);
3127
3128 hlen = GET_BE_U_2(bgp_header->bgp_len);
3129 if (hlen < BGP_SIZE) {
3130 ND_PRINT("\nmessage length %u < %u", hlen, BGP_SIZE);
3131 nd_print_invalid(ndo);
3132 break;
3133 }
3134
3135 if (ND_TTEST_LEN(p, hlen)) {
3136 if (!bgp_pdu_print(ndo, p, hlen))
3137 return;
3138 p += hlen;
3139 start = p;
3140 } else {
3141 ND_PRINT("\n[|BGP %s]",
3142 tok2str(bgp_msg_values,
3143 "Unknown Message Type",
3144 GET_U_1(bgp_header->bgp_type)));
3145 break;
3146 }
3147 }
3148
3149 return;
3150
3151 trunc:
3152 nd_print_trunc(ndo);
3153 }
[mirror] the TCPdump network dissector