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BGP: Address a -Wformat-truncation= compiler warning
[tcpdump] / print-bgp.c
1 /*
2 * Copyright (C) 1999 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * Extensively modified by Hannes Gredler (hannes@gredler.at) for more
30 * complete BGP support.
31 */
32
33 /* \summary: Border Gateway Protocol (BGP) printer */
34
35 /* specification: RFC 4271 */
36
37 #ifdef HAVE_CONFIG_H
38 #include <config.h>
39 #endif
40
41 #include "netdissect-stdinc.h"
42
43 #include <stdio.h>
44 #include <string.h>
45
46 #include "netdissect.h"
47 #include "addrtoname.h"
48 #include "extract.h"
49 #include "af.h"
50 #include "l2vpn.h"
51
52 struct bgp {
53 nd_byte bgp_marker[16];
54 nd_uint16_t bgp_len;
55 nd_uint8_t bgp_type;
56 };
57 #define BGP_SIZE 19 /* unaligned */
58
59 #define BGP_OPEN 1
60 #define BGP_UPDATE 2
61 #define BGP_NOTIFICATION 3
62 #define BGP_KEEPALIVE 4
63 #define BGP_ROUTE_REFRESH 5
64
65 static const struct tok bgp_msg_values[] = {
66 { BGP_OPEN, "Open"},
67 { BGP_UPDATE, "Update"},
68 { BGP_NOTIFICATION, "Notification"},
69 { BGP_KEEPALIVE, "Keepalive"},
70 { BGP_ROUTE_REFRESH, "Route Refresh"},
71 { 0, NULL}
72 };
73
74 struct bgp_open {
75 nd_byte bgpo_marker[16];
76 nd_uint16_t bgpo_len;
77 nd_uint8_t bgpo_type;
78 nd_uint8_t bgpo_version;
79 nd_uint16_t bgpo_myas;
80 nd_uint16_t bgpo_holdtime;
81 nd_uint32_t bgpo_id;
82 nd_uint8_t bgpo_optlen;
83 /* options should follow */
84 };
85 #define BGP_OPEN_SIZE 29 /* unaligned */
86
87 struct bgp_opt {
88 nd_uint8_t bgpopt_type;
89 nd_uint8_t bgpopt_len;
90 /* variable length */
91 };
92 #define BGP_OPT_SIZE 2 /* some compilers may pad to 4 bytes */
93 #define BGP_CAP_HEADER_SIZE 2 /* some compilers may pad to 4 bytes */
94
95 struct bgp_notification {
96 nd_byte bgpn_marker[16];
97 nd_uint16_t bgpn_len;
98 nd_uint8_t bgpn_type;
99 nd_uint8_t bgpn_major;
100 nd_uint8_t bgpn_minor;
101 };
102 #define BGP_NOTIFICATION_SIZE 21 /* unaligned */
103
104 struct bgp_route_refresh {
105 nd_byte bgp_marker[16];
106 nd_uint16_t len;
107 nd_uint8_t type; /* No padding after this; afi is, in fact, not aligned */
108 nd_uint16_t afi;
109 nd_uint8_t res;
110 nd_uint8_t safi;
111 };
112 #define BGP_ROUTE_REFRESH_SIZE 23
113
114 #define bgp_attr_lenlen(flags, p) \
115 (((flags) & 0x10) ? 2U : 1U)
116 #define bgp_attr_len(flags, p) \
117 (((flags) & 0x10) ? GET_BE_U_2(p) : GET_U_1(p))
118
119 #define BGPTYPE_ORIGIN 1
120 #define BGPTYPE_AS_PATH 2
121 #define BGPTYPE_NEXT_HOP 3
122 #define BGPTYPE_MULTI_EXIT_DISC 4
123 #define BGPTYPE_LOCAL_PREF 5
124 #define BGPTYPE_ATOMIC_AGGREGATE 6
125 #define BGPTYPE_AGGREGATOR 7
126 #define BGPTYPE_COMMUNITIES 8 /* RFC1997 */
127 #define BGPTYPE_ORIGINATOR_ID 9 /* RFC4456 */
128 #define BGPTYPE_CLUSTER_LIST 10 /* RFC4456 */
129 #define BGPTYPE_DPA 11 /* deprecated, draft-ietf-idr-bgp-dpa */
130 #define BGPTYPE_ADVERTISERS 12 /* deprecated RFC1863 */
131 #define BGPTYPE_RCID_PATH 13 /* deprecated RFC1863 */
132 #define BGPTYPE_MP_REACH_NLRI 14 /* RFC4760 */
133 #define BGPTYPE_MP_UNREACH_NLRI 15 /* RFC4760 */
134 #define BGPTYPE_EXTD_COMMUNITIES 16 /* RFC4360 */
135 #define BGPTYPE_AS4_PATH 17 /* RFC6793 */
136 #define BGPTYPE_AGGREGATOR4 18 /* RFC6793 */
137 #define BGPTYPE_PMSI_TUNNEL 22 /* RFC6514 */
138 #define BGPTYPE_TUNNEL_ENCAP 23 /* RFC5512 */
139 #define BGPTYPE_TRAFFIC_ENG 24 /* RFC5543 */
140 #define BGPTYPE_IPV6_EXTD_COMMUNITIES 25 /* RFC5701 */
141 #define BGPTYPE_AIGP 26 /* RFC7311 */
142 #define BGPTYPE_PE_DISTINGUISHER_LABEL 27 /* RFC6514 */
143 #define BGPTYPE_ENTROPY_LABEL 28 /* RFC6790 */
144 #define BGPTYPE_LARGE_COMMUNITY 32 /* draft-ietf-idr-large-community-05 */
145 #define BGPTYPE_ATTR_SET 128 /* RFC6368 */
146
147 #define BGP_MP_NLRI_MINSIZE 3 /* End of RIB Marker detection */
148
149 static const struct tok bgp_attr_values[] = {
150 { BGPTYPE_ORIGIN, "Origin"},
151 { BGPTYPE_AS_PATH, "AS Path"},
152 { BGPTYPE_AS4_PATH, "AS4 Path"},
153 { BGPTYPE_NEXT_HOP, "Next Hop"},
154 { BGPTYPE_MULTI_EXIT_DISC, "Multi Exit Discriminator"},
155 { BGPTYPE_LOCAL_PREF, "Local Preference"},
156 { BGPTYPE_ATOMIC_AGGREGATE, "Atomic Aggregate"},
157 { BGPTYPE_AGGREGATOR, "Aggregator"},
158 { BGPTYPE_AGGREGATOR4, "Aggregator4"},
159 { BGPTYPE_COMMUNITIES, "Community"},
160 { BGPTYPE_ORIGINATOR_ID, "Originator ID"},
161 { BGPTYPE_CLUSTER_LIST, "Cluster List"},
162 { BGPTYPE_DPA, "DPA"},
163 { BGPTYPE_ADVERTISERS, "Advertisers"},
164 { BGPTYPE_RCID_PATH, "RCID Path / Cluster ID"},
165 { BGPTYPE_MP_REACH_NLRI, "Multi-Protocol Reach NLRI"},
166 { BGPTYPE_MP_UNREACH_NLRI, "Multi-Protocol Unreach NLRI"},
167 { BGPTYPE_EXTD_COMMUNITIES, "Extended Community"},
168 { BGPTYPE_PMSI_TUNNEL, "PMSI Tunnel"},
169 { BGPTYPE_TUNNEL_ENCAP, "Tunnel Encapsulation"},
170 { BGPTYPE_TRAFFIC_ENG, "Traffic Engineering"},
171 { BGPTYPE_IPV6_EXTD_COMMUNITIES, "IPv6 Extended Community"},
172 { BGPTYPE_AIGP, "Accumulated IGP Metric"},
173 { BGPTYPE_PE_DISTINGUISHER_LABEL, "PE Distinguisher Label"},
174 { BGPTYPE_ENTROPY_LABEL, "Entropy Label"},
175 { BGPTYPE_LARGE_COMMUNITY, "Large Community"},
176 { BGPTYPE_ATTR_SET, "Attribute Set"},
177 { 255, "Reserved for development"},
178 { 0, NULL}
179 };
180
181 #define BGP_AS_SET 1
182 #define BGP_AS_SEQUENCE 2
183 #define BGP_CONFED_AS_SEQUENCE 3 /* draft-ietf-idr-rfc3065bis-01 */
184 #define BGP_CONFED_AS_SET 4 /* draft-ietf-idr-rfc3065bis-01 */
185
186 #define BGP_AS_SEG_TYPE_MIN BGP_AS_SET
187 #define BGP_AS_SEG_TYPE_MAX BGP_CONFED_AS_SET
188
189 static const struct tok bgp_as_path_segment_open_values[] = {
190 { BGP_AS_SEQUENCE, ""},
191 { BGP_AS_SET, "{ "},
192 { BGP_CONFED_AS_SEQUENCE, "( "},
193 { BGP_CONFED_AS_SET, "({ "},
194 { 0, NULL}
195 };
196
197 static const struct tok bgp_as_path_segment_close_values[] = {
198 { BGP_AS_SEQUENCE, ""},
199 { BGP_AS_SET, "}"},
200 { BGP_CONFED_AS_SEQUENCE, ")"},
201 { BGP_CONFED_AS_SET, "})"},
202 { 0, NULL}
203 };
204
205 #define BGP_OPT_AUTH 1
206 #define BGP_OPT_CAP 2
207
208 static const struct tok bgp_opt_values[] = {
209 { BGP_OPT_AUTH, "Authentication Information"},
210 { BGP_OPT_CAP, "Capabilities Advertisement"},
211 { 0, NULL}
212 };
213
214 #define BGP_CAPCODE_MP 1 /* RFC2858 */
215 #define BGP_CAPCODE_RR 2 /* RFC2918 */
216 #define BGP_CAPCODE_ORF 3 /* RFC5291 */
217 #define BGP_CAPCODE_MR 4 /* RFC3107 */
218 #define BGP_CAPCODE_EXT_NH 5 /* RFC5549 */
219 #define BGP_CAPCODE_ML 8 /* RFC8277 */
220 #define BGP_CAPCODE_RESTART 64 /* RFC4724 */
221 #define BGP_CAPCODE_AS_NEW 65 /* RFC6793 */
222 #define BGP_CAPCODE_DYN_CAP 67 /* draft-ietf-idr-dynamic-cap */
223 #define BGP_CAPCODE_MULTISESS 68 /* draft-ietf-idr-bgp-multisession */
224 #define BGP_CAPCODE_ADD_PATH 69 /* RFC7911 */
225 #define BGP_CAPCODE_ENH_RR 70 /* draft-keyur-bgp-enhanced-route-refresh */
226 #define BGP_CAPCODE_LLGR 71 /* draft-uttaro-idr-bgp-persistence-05 */
227 #define BGP_CAPCODE_RR_CISCO 128
228
229 static const struct tok bgp_capcode_values[] = {
230 { BGP_CAPCODE_MP, "Multiprotocol Extensions"},
231 { BGP_CAPCODE_RR, "Route Refresh"},
232 { BGP_CAPCODE_ORF, "Cooperative Route Filtering"},
233 { BGP_CAPCODE_MR, "Multiple Routes to a Destination"},
234 { BGP_CAPCODE_EXT_NH, "Extended Next Hop Encoding"},
235 { BGP_CAPCODE_ML, "Multiple Labels"},
236 { BGP_CAPCODE_RESTART, "Graceful Restart"},
237 { BGP_CAPCODE_AS_NEW, "32-Bit AS Number"},
238 { BGP_CAPCODE_DYN_CAP, "Dynamic Capability"},
239 { BGP_CAPCODE_MULTISESS, "Multisession BGP"},
240 { BGP_CAPCODE_ADD_PATH, "Multiple Paths"},
241 { BGP_CAPCODE_ENH_RR, "Enhanced Route Refresh"},
242 { BGP_CAPCODE_LLGR, "Long-lived Graceful Restart"},
243 { BGP_CAPCODE_RR_CISCO, "Route Refresh (Cisco)"},
244 { 0, NULL}
245 };
246
247 #define BGP_NOTIFY_MAJOR_MSG 1
248 #define BGP_NOTIFY_MAJOR_OPEN 2
249 #define BGP_NOTIFY_MAJOR_UPDATE 3
250 #define BGP_NOTIFY_MAJOR_HOLDTIME 4
251 #define BGP_NOTIFY_MAJOR_FSM 5
252 #define BGP_NOTIFY_MAJOR_CEASE 6
253 #define BGP_NOTIFY_MAJOR_CAP 7
254
255 static const struct tok bgp_notify_major_values[] = {
256 { BGP_NOTIFY_MAJOR_MSG, "Message Header Error"},
257 { BGP_NOTIFY_MAJOR_OPEN, "OPEN Message Error"},
258 { BGP_NOTIFY_MAJOR_UPDATE, "UPDATE Message Error"},
259 { BGP_NOTIFY_MAJOR_HOLDTIME,"Hold Timer Expired"},
260 { BGP_NOTIFY_MAJOR_FSM, "Finite State Machine Error"},
261 { BGP_NOTIFY_MAJOR_CEASE, "Cease"},
262 { BGP_NOTIFY_MAJOR_CAP, "Capability Message Error"},
263 { 0, NULL}
264 };
265
266 /* draft-ietf-idr-cease-subcode-02 */
267 #define BGP_NOTIFY_MINOR_CEASE_MAXPRFX 1
268 /* draft-ietf-idr-shutdown-07 */
269 #define BGP_NOTIFY_MINOR_CEASE_SHUT 2
270 #define BGP_NOTIFY_MINOR_CEASE_RESET 4
271 #define BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN 128
272 static const struct tok bgp_notify_minor_cease_values[] = {
273 { BGP_NOTIFY_MINOR_CEASE_MAXPRFX, "Maximum Number of Prefixes Reached"},
274 { BGP_NOTIFY_MINOR_CEASE_SHUT, "Administrative Shutdown"},
275 { 3, "Peer Unconfigured"},
276 { BGP_NOTIFY_MINOR_CEASE_RESET, "Administrative Reset"},
277 { 5, "Connection Rejected"},
278 { 6, "Other Configuration Change"},
279 { 7, "Connection Collision Resolution"},
280 { 0, NULL}
281 };
282
283 static const struct tok bgp_notify_minor_msg_values[] = {
284 { 1, "Connection Not Synchronized"},
285 { 2, "Bad Message Length"},
286 { 3, "Bad Message Type"},
287 { 0, NULL}
288 };
289
290 static const struct tok bgp_notify_minor_open_values[] = {
291 { 1, "Unsupported Version Number"},
292 { 2, "Bad Peer AS"},
293 { 3, "Bad BGP Identifier"},
294 { 4, "Unsupported Optional Parameter"},
295 { 5, "Authentication Failure"},
296 { 6, "Unacceptable Hold Time"},
297 { 7, "Capability Message Error"},
298 { 0, NULL}
299 };
300
301 static const struct tok bgp_notify_minor_update_values[] = {
302 { 1, "Malformed Attribute List"},
303 { 2, "Unrecognized Well-known Attribute"},
304 { 3, "Missing Well-known Attribute"},
305 { 4, "Attribute Flags Error"},
306 { 5, "Attribute Length Error"},
307 { 6, "Invalid ORIGIN Attribute"},
308 { 7, "AS Routing Loop"},
309 { 8, "Invalid NEXT_HOP Attribute"},
310 { 9, "Optional Attribute Error"},
311 { 10, "Invalid Network Field"},
312 { 11, "Malformed AS_PATH"},
313 { 0, NULL}
314 };
315
316 static const struct tok bgp_notify_minor_fsm_values[] = {
317 { 0, "Unspecified Error"},
318 { 1, "In OpenSent State"},
319 { 2, "In OpenConfirm State"},
320 { 3, "In Established State"},
321 { 0, NULL }
322 };
323
324 static const struct tok bgp_notify_minor_cap_values[] = {
325 { 1, "Invalid Action Value" },
326 { 2, "Invalid Capability Length" },
327 { 3, "Malformed Capability Value" },
328 { 4, "Unsupported Capability Code" },
329 { 0, NULL }
330 };
331
332 static const struct tok bgp_origin_values[] = {
333 { 0, "IGP"},
334 { 1, "EGP"},
335 { 2, "Incomplete"},
336 { 0, NULL}
337 };
338
339 #define BGP_PMSI_TUNNEL_RSVP_P2MP 1
340 #define BGP_PMSI_TUNNEL_LDP_P2MP 2
341 #define BGP_PMSI_TUNNEL_PIM_SSM 3
342 #define BGP_PMSI_TUNNEL_PIM_SM 4
343 #define BGP_PMSI_TUNNEL_PIM_BIDIR 5
344 #define BGP_PMSI_TUNNEL_INGRESS 6
345 #define BGP_PMSI_TUNNEL_LDP_MP2MP 7
346
347 static const struct tok bgp_pmsi_tunnel_values[] = {
348 { BGP_PMSI_TUNNEL_RSVP_P2MP, "RSVP-TE P2MP LSP"},
349 { BGP_PMSI_TUNNEL_LDP_P2MP, "LDP P2MP LSP"},
350 { BGP_PMSI_TUNNEL_PIM_SSM, "PIM-SSM Tree"},
351 { BGP_PMSI_TUNNEL_PIM_SM, "PIM-SM Tree"},
352 { BGP_PMSI_TUNNEL_PIM_BIDIR, "PIM-Bidir Tree"},
353 { BGP_PMSI_TUNNEL_INGRESS, "Ingress Replication"},
354 { BGP_PMSI_TUNNEL_LDP_MP2MP, "LDP MP2MP LSP"},
355 { 0, NULL}
356 };
357
358 static const struct tok bgp_pmsi_flag_values[] = {
359 { 0x01, "Leaf Information required"},
360 { 0, NULL}
361 };
362
363 #define BGP_AIGP_TLV 1
364
365 static const struct tok bgp_aigp_values[] = {
366 { BGP_AIGP_TLV, "AIGP"},
367 { 0, NULL}
368 };
369
370 /* Subsequent address family identifier, RFC2283 section 7 */
371 #define SAFNUM_RES 0
372 #define SAFNUM_UNICAST 1
373 #define SAFNUM_MULTICAST 2
374 #define SAFNUM_UNIMULTICAST 3 /* deprecated now */
375 /* labeled BGP RFC3107 */
376 #define SAFNUM_LABUNICAST 4
377 /* RFC6514 */
378 #define SAFNUM_MULTICAST_VPN 5
379 /* draft-nalawade-kapoor-tunnel-safi */
380 #define SAFNUM_TUNNEL 64
381 /* RFC4761 */
382 #define SAFNUM_VPLS 65
383 /* RFC6037 */
384 #define SAFNUM_MDT 66
385 /* RFC7432 */
386 #define SAFNUM_EVPN 70
387 /* RFC4364 */
388 #define SAFNUM_VPNUNICAST 128
389 /* RFC6513 */
390 #define SAFNUM_VPNMULTICAST 129
391 #define SAFNUM_VPNUNIMULTICAST 130 /* deprecated now */
392 /* RFC4684 */
393 #define SAFNUM_RT_ROUTING_INFO 132
394
395 #define BGP_VPN_RD_LEN 8
396
397 static const struct tok bgp_safi_values[] = {
398 { SAFNUM_RES, "Reserved"},
399 { SAFNUM_UNICAST, "Unicast"},
400 { SAFNUM_MULTICAST, "Multicast"},
401 { SAFNUM_UNIMULTICAST, "Unicast+Multicast"},
402 { SAFNUM_LABUNICAST, "labeled Unicast"},
403 { SAFNUM_TUNNEL, "Tunnel"},
404 { SAFNUM_VPLS, "VPLS"},
405 { SAFNUM_MDT, "MDT"},
406 { SAFNUM_EVPN, "EVPN"},
407 { SAFNUM_VPNUNICAST, "labeled VPN Unicast"},
408 { SAFNUM_VPNMULTICAST, "labeled VPN Multicast"},
409 { SAFNUM_VPNUNIMULTICAST, "labeled VPN Unicast+Multicast"},
410 { SAFNUM_RT_ROUTING_INFO, "Route Target Routing Information"},
411 { SAFNUM_MULTICAST_VPN, "Multicast VPN"},
412 { 0, NULL }
413 };
414
415 /* well-known community */
416 #define BGP_COMMUNITY_NO_EXPORT 0xffffff01
417 #define BGP_COMMUNITY_NO_ADVERT 0xffffff02
418 #define BGP_COMMUNITY_NO_EXPORT_SUBCONFED 0xffffff03
419
420 /* Extended community type - RFC 4360 */
421 #define BGP_EXT_COM_RT_0 0x0002 /* Route Target,Format AS(2bytes):AN(4bytes) */
422 #define BGP_EXT_COM_RT_1 0x0102 /* Route Target,Format IP address:AN(2bytes) */
423 #define BGP_EXT_COM_RT_2 0x0202 /* Route Target,Format AN(4bytes):local(2bytes) */
424 #define BGP_EXT_COM_RO_0 0x0003 /* Route Origin,Format AS(2bytes):AN(4bytes) */
425 #define BGP_EXT_COM_RO_1 0x0103 /* Route Origin,Format IP address:AN(2bytes) */
426 #define BGP_EXT_COM_RO_2 0x0203 /* Route Origin,Format AN(4bytes):local(2bytes) */
427 #define BGP_EXT_COM_LINKBAND 0x4004 /* Link Bandwidth,Format AS(2B):Bandwidth(4B) */
428 /* rfc2547 bgp-mpls-vpns */
429 #define BGP_EXT_COM_VPN_ORIGIN 0x0005 /* OSPF Domain ID / VPN of Origin - draft-rosen-vpns-ospf-bgp-mpls */
430 #define BGP_EXT_COM_VPN_ORIGIN2 0x0105 /* duplicate - keep for backwards compatibility */
431 #define BGP_EXT_COM_VPN_ORIGIN3 0x0205 /* duplicate - keep for backwards compatibility */
432 #define BGP_EXT_COM_VPN_ORIGIN4 0x8005 /* duplicate - keep for backwards compatibility */
433
434 #define BGP_EXT_COM_OSPF_RTYPE 0x0306 /* OSPF Route Type,Format Area(4B):RouteType(1B):Options(1B) */
435 #define BGP_EXT_COM_OSPF_RTYPE2 0x8000 /* duplicate - keep for backwards compatibility */
436 #define BGP_EXT_COM_ENCAP 0x030c /* rfc5512 */
437
438 #define BGP_EXT_COM_OSPF_RID 0x0107 /* OSPF Router ID,Format RouterID(4B):Unused(2B) */
439 #define BGP_EXT_COM_OSPF_RID2 0x8001 /* duplicate - keep for backwards compatibility */
440
441 #define BGP_EXT_COM_L2INFO 0x800a /* draft-kompella-ppvpn-l2vpn */
442
443 #define BGP_EXT_COM_SOURCE_AS 0x0009 /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */
444 #define BGP_EXT_COM_VRF_RT_IMP 0x010b /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */
445 #define BGP_EXT_COM_L2VPN_RT_0 0x000a /* L2VPN Identifier,Format AS(2bytes):AN(4bytes) */
446 #define BGP_EXT_COM_L2VPN_RT_1 0xF10a /* L2VPN Identifier,Format IP address:AN(2bytes) */
447
448 /* https://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a00801eb09a.shtml */
449 #define BGP_EXT_COM_EIGRP_GEN 0x8800
450 #define BGP_EXT_COM_EIGRP_METRIC_AS_DELAY 0x8801
451 #define BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW 0x8802
452 #define BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU 0x8803
453 #define BGP_EXT_COM_EIGRP_EXT_REMAS_REMID 0x8804
454 #define BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC 0x8805
455
456 static const struct tok bgp_extd_comm_flag_values[] = {
457 { 0x8000, "vendor-specific"},
458 { 0x4000, "non-transitive"},
459 { 0, NULL},
460 };
461
462 static const struct tok bgp_extd_comm_subtype_values[] = {
463 { BGP_EXT_COM_RT_0, "target"},
464 { BGP_EXT_COM_RT_1, "target"},
465 { BGP_EXT_COM_RT_2, "target"},
466 { BGP_EXT_COM_RO_0, "origin"},
467 { BGP_EXT_COM_RO_1, "origin"},
468 { BGP_EXT_COM_RO_2, "origin"},
469 { BGP_EXT_COM_LINKBAND, "link-BW"},
470 { BGP_EXT_COM_VPN_ORIGIN, "ospf-domain"},
471 { BGP_EXT_COM_VPN_ORIGIN2, "ospf-domain"},
472 { BGP_EXT_COM_VPN_ORIGIN3, "ospf-domain"},
473 { BGP_EXT_COM_VPN_ORIGIN4, "ospf-domain"},
474 { BGP_EXT_COM_OSPF_RTYPE, "ospf-route-type"},
475 { BGP_EXT_COM_OSPF_RTYPE2, "ospf-route-type"},
476 { BGP_EXT_COM_ENCAP, "encapsulation"},
477 { BGP_EXT_COM_OSPF_RID, "ospf-router-id"},
478 { BGP_EXT_COM_OSPF_RID2, "ospf-router-id"},
479 { BGP_EXT_COM_L2INFO, "layer2-info"},
480 { BGP_EXT_COM_EIGRP_GEN, "eigrp-general-route (flag, tag)" },
481 { BGP_EXT_COM_EIGRP_METRIC_AS_DELAY, "eigrp-route-metric (AS, delay)" },
482 { BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW, "eigrp-route-metric (reliability, nexthop, bandwidth)" },
483 { BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU, "eigrp-route-metric (load, MTU)" },
484 { BGP_EXT_COM_EIGRP_EXT_REMAS_REMID, "eigrp-external-route (remote-AS, remote-ID)" },
485 { BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC, "eigrp-external-route (remote-proto, remote-metric)" },
486 { BGP_EXT_COM_SOURCE_AS, "source-AS" },
487 { BGP_EXT_COM_VRF_RT_IMP, "vrf-route-import"},
488 { BGP_EXT_COM_L2VPN_RT_0, "l2vpn-id"},
489 { BGP_EXT_COM_L2VPN_RT_1, "l2vpn-id"},
490 { 0, NULL},
491 };
492
493 /* RFC RFC5512 BGP Tunnel Encapsulation Attribute Tunnel Types */
494 #define BGP_ENCAP_TUNNEL_L2TPV3_IP 1
495 #define BGP_ENCAP_TUNNEL_GRE 2
496 #define BGP_ENCAP_TUNNEL_TRANSMIT 3
497 #define BGP_ENCAP_TUNNEL_IPSEC 4
498 #define BGP_ENCAP_TUNNEL_IP_IPSEC 5
499 #define BGP_ENCAP_TUNNEL_MPLS_IP 6
500 #define BGP_ENCAP_TUNNEL_IP_IP 7
501 #define BGP_ENCAP_TUNNEL_VXLAN 8
502 #define BGP_ENCAP_TUNNEL_NVGRE 9
503 #define BGP_ENCAP_TUNNEL_MPLS 10
504 #define BGP_ENCAP_TUNNEL_MPLS_GRE 11
505 #define BGP_ENCAP_TUNNEL_VXLAN_GPE 12
506 #define BGP_ENCAP_TUNNEL_MPLS_UDP 13
507 #define BGP_ENCAP_TUNNEL_IPV6 14
508 #define BGP_ENCAP_TUNNEL_SR_TE 15
509 #define BGP_ENCAP_TUNNEL_BARE 16
510 #define BGP_ENCAP_TUNNEL_SR 17
511
512 static const struct tok bgp_extd_comm_encap_tunnel_values[] = {
513 { BGP_ENCAP_TUNNEL_L2TPV3_IP, "L2TPv3 over IP"},
514 { BGP_ENCAP_TUNNEL_GRE, "GRE"},
515 { BGP_ENCAP_TUNNEL_TRANSMIT, "Transmit Tunnel"},
516 { BGP_ENCAP_TUNNEL_IPSEC, "IPsec"},
517 { BGP_ENCAP_TUNNEL_IP_IPSEC, "IP in IP with IPsec"},
518 { BGP_ENCAP_TUNNEL_MPLS_IP, "MPLS in IP with IPsec"},
519 { BGP_ENCAP_TUNNEL_IP_IP, "IP in IP"},
520 { BGP_ENCAP_TUNNEL_VXLAN, "VXLAN"},
521 { BGP_ENCAP_TUNNEL_NVGRE, "NVGRE"},
522 { BGP_ENCAP_TUNNEL_MPLS, "MPLS"},
523 { BGP_ENCAP_TUNNEL_MPLS_GRE, "MPLS in GRE"},
524 { BGP_ENCAP_TUNNEL_VXLAN_GPE, "VXLAN GPE"},
525 { BGP_ENCAP_TUNNEL_MPLS_UDP, "MPLS in UDP"},
526 { BGP_ENCAP_TUNNEL_IPV6, "IPv6"},
527 { BGP_ENCAP_TUNNEL_SR_TE, "SR TE"},
528 { BGP_ENCAP_TUNNEL_BARE, "Bare"},
529 { BGP_ENCAP_TUNNEL_SR, "SR"},
530 { 0, NULL},
531 };
532
533 /* OSPF codes for BGP_EXT_COM_OSPF_RTYPE draft-rosen-vpns-ospf-bgp-mpls */
534 #define BGP_OSPF_RTYPE_RTR 1 /* OSPF Router LSA */
535 #define BGP_OSPF_RTYPE_NET 2 /* OSPF Network LSA */
536 #define BGP_OSPF_RTYPE_SUM 3 /* OSPF Summary LSA */
537 #define BGP_OSPF_RTYPE_EXT 5 /* OSPF External LSA, note that ASBR doesn't apply to MPLS-VPN */
538 #define BGP_OSPF_RTYPE_NSSA 7 /* OSPF NSSA External*/
539 #define BGP_OSPF_RTYPE_SHAM 129 /* OSPF-MPLS-VPN Sham link */
540 #define BGP_OSPF_RTYPE_METRIC_TYPE 0x1 /* LSB of RTYPE Options Field */
541
542 static const struct tok bgp_extd_comm_ospf_rtype_values[] = {
543 { BGP_OSPF_RTYPE_RTR, "Router" },
544 { BGP_OSPF_RTYPE_NET, "Network" },
545 { BGP_OSPF_RTYPE_SUM, "Summary" },
546 { BGP_OSPF_RTYPE_EXT, "External" },
547 { BGP_OSPF_RTYPE_NSSA,"NSSA External" },
548 { BGP_OSPF_RTYPE_SHAM,"MPLS-VPN Sham" },
549 { 0, NULL },
550 };
551
552 /* ADD-PATH Send/Receive field values */
553 static const struct tok bgp_add_path_recvsend[] = {
554 { 1, "Receive" },
555 { 2, "Send" },
556 { 3, "Both" },
557 { 0, NULL },
558 };
559
560 /* allocate space for the largest possible string */
561 static char astostr[sizeof("xxxxx.xxxxx")];
562
563 /*
564 * as_printf
565 *
566 * Convert an AS number into a string and return string pointer.
567 *
568 * Depending on bflag is set or not, AS number is converted into ASDOT notation
569 * or plain number notation.
570 *
571 */
572 static char *
573 as_printf(netdissect_options *ndo,
574 char *str, size_t size, u_int asnum)
575 {
576 if (!ndo->ndo_bflag || asnum <= 0xFFFF) {
577 snprintf(str, size, "%u", asnum);
578 } else {
579 snprintf(str, size, "%u.%u", asnum >> 16, asnum & 0xFFFF);
580 }
581 return str;
582 }
583
584 #define ITEMCHECK(minlen) if (itemlen < minlen) goto badtlv;
585
586 int
587 decode_prefix4(netdissect_options *ndo,
588 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
589 {
590 nd_ipv4 addr;
591 u_int plen, plenbytes;
592
593 ND_TCHECK_1(pptr);
594 ITEMCHECK(1);
595 plen = GET_U_1(pptr);
596 if (32 < plen)
597 return -1;
598 itemlen -= 1;
599
600 memset(&addr, 0, sizeof(addr));
601 plenbytes = (plen + 7) / 8;
602 ND_TCHECK_LEN(pptr + 1, plenbytes);
603 ITEMCHECK(plenbytes);
604 memcpy(&addr, pptr + 1, plenbytes);
605 if (plen % 8) {
606 ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
607 }
608 snprintf(buf, buflen, "%s/%u", ipaddr_string(ndo, (const u_char *)&addr), plen);
609 return 1 + plenbytes;
610
611 trunc:
612 return -2;
613
614 badtlv:
615 return -3;
616 }
617
618 static int
619 decode_labeled_prefix4(netdissect_options *ndo,
620 const u_char *pptr, u_int itemlen, char *buf,
621 size_t buflen)
622 {
623 nd_ipv4 addr;
624 u_int plen, plenbytes;
625
626 /* prefix length and label = 4 bytes */
627 ND_TCHECK_4(pptr);
628 ITEMCHECK(4);
629 plen = GET_U_1(pptr); /* get prefix length */
630
631 /* this is one of the weirdnesses of rfc3107
632 the label length (actually the label + COS bits)
633 is added to the prefix length;
634 we also do only read out just one label -
635 there is no real application for advertisement of
636 stacked labels in a single BGP message
637 */
638
639 if (24 > plen)
640 return -1;
641
642 plen-=24; /* adjust prefixlen - labellength */
643
644 if (32 < plen)
645 return -1;
646 itemlen -= 4;
647
648 memset(&addr, 0, sizeof(addr));
649 plenbytes = (plen + 7) / 8;
650 ND_TCHECK_LEN(pptr + 4, plenbytes);
651 ITEMCHECK(plenbytes);
652 memcpy(&addr, pptr + 4, plenbytes);
653 if (plen % 8) {
654 ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
655 }
656 /* the label may get offsetted by 4 bits so lets shift it right */
657 snprintf(buf, buflen, "%s/%u, label:%u %s",
658 ipaddr_string(ndo, (const u_char *)&addr),
659 plen,
660 GET_BE_U_3(pptr + 1)>>4,
661 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
662
663 return 4 + plenbytes;
664
665 trunc:
666 return -2;
667
668 badtlv:
669 return -3;
670 }
671
672 /*
673 * bgp_vpn_ip_print
674 *
675 * print an ipv4 or ipv6 address into a buffer dependend on address length.
676 */
677 static char *
678 bgp_vpn_ip_print(netdissect_options *ndo,
679 const u_char *pptr, u_int addr_length)
680 {
681
682 /* worst case string is s fully formatted v6 address */
683 static char addr[sizeof("1234:5678:89ab:cdef:1234:5678:89ab:cdef")];
684 char *pos = addr;
685
686 switch(addr_length) {
687 case (sizeof(nd_ipv4) << 3): /* 32 */
688 ND_TCHECK_LEN(pptr, sizeof(nd_ipv4));
689 snprintf(pos, sizeof(addr), "%s", GET_IPADDR_STRING(pptr));
690 break;
691 case (sizeof(nd_ipv6) << 3): /* 128 */
692 ND_TCHECK_LEN(pptr, sizeof(nd_ipv6));
693 snprintf(pos, sizeof(addr), "%s", GET_IP6ADDR_STRING(pptr));
694 break;
695 default:
696 snprintf(pos, sizeof(addr), "bogus address length %u", addr_length);
697 break;
698 }
699 pos += strlen(pos);
700
701 trunc:
702 *(pos) = '\0';
703 return (addr);
704 }
705
706 /*
707 * bgp_vpn_sg_print
708 *
709 * print an multicast s,g entry into a buffer.
710 * the s,g entry is encoded like this.
711 *
712 * +-----------------------------------+
713 * | Multicast Source Length (1 octet) |
714 * +-----------------------------------+
715 * | Multicast Source (Variable) |
716 * +-----------------------------------+
717 * | Multicast Group Length (1 octet) |
718 * +-----------------------------------+
719 * | Multicast Group (Variable) |
720 * +-----------------------------------+
721 *
722 * return the number of bytes read from the wire.
723 */
724 static u_int
725 bgp_vpn_sg_print(netdissect_options *ndo,
726 const u_char *pptr, char *buf, size_t buflen)
727 {
728 uint8_t addr_length;
729 u_int total_length, offset;
730
731 total_length = 0;
732
733 /* Source address length, encoded in bits */
734 ND_TCHECK_1(pptr);
735 addr_length = GET_U_1(pptr);
736 pptr++;
737
738 /* Source address */
739 ND_TCHECK_LEN(pptr, (addr_length >> 3));
740 total_length += (addr_length >> 3) + 1;
741 offset = (u_int)strlen(buf);
742 if (addr_length) {
743 snprintf(buf + offset, buflen - offset, ", Source %s",
744 bgp_vpn_ip_print(ndo, pptr, addr_length));
745 pptr += (addr_length >> 3);
746 }
747
748 /* Group address length, encoded in bits */
749 ND_TCHECK_1(pptr);
750 addr_length = GET_U_1(pptr);
751 pptr++;
752
753 /* Group address */
754 ND_TCHECK_LEN(pptr, (addr_length >> 3));
755 total_length += (addr_length >> 3) + 1;
756 offset = (u_int)strlen(buf);
757 if (addr_length) {
758 snprintf(buf + offset, buflen - offset, ", Group %s",
759 bgp_vpn_ip_print(ndo, pptr, addr_length));
760 pptr += (addr_length >> 3);
761 }
762
763 trunc:
764 return (total_length);
765 }
766
767 /* Print an RFC 4364 Route Distinguisher */
768 const char *
769 bgp_vpn_rd_print(netdissect_options *ndo,
770 const u_char *pptr)
771 {
772 /* allocate space for the largest possible string */
773 static char rd[sizeof("xxxxx.xxxxx:xxxxx (xxx.xxx.xxx.xxx:xxxxx)")];
774 char *pos = rd;
775
776 /* ok lets load the RD format */
777 switch (GET_BE_U_2(pptr)) {
778
779 case 0:
780 /* 2-byte-AS:number fmt */
781 snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (= %u.%u.%u.%u)",
782 GET_BE_U_2(pptr + 2),
783 GET_BE_U_4(pptr + 4),
784 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
785 GET_U_1(pptr + 6), GET_U_1(pptr + 7));
786 break;
787
788 case 1:
789 /* IP-address:AS fmt */
790 snprintf(pos, sizeof(rd) - (pos - rd), "%u.%u.%u.%u:%u",
791 GET_U_1(pptr + 2), GET_U_1(pptr + 3),
792 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
793 GET_BE_U_2(pptr + 6));
794 break;
795
796 case 2:
797 /* 4-byte-AS:number fmt */
798 snprintf(pos, sizeof(rd) - (pos - rd), "%s:%u (%u.%u.%u.%u:%u)",
799 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 2)),
800 GET_BE_U_2(pptr + 6), GET_U_1(pptr + 2),
801 GET_U_1(pptr + 3), GET_U_1(pptr + 4),
802 GET_U_1(pptr + 5), GET_BE_U_2(pptr + 6));
803 break;
804 default:
805 snprintf(pos, sizeof(rd) - (pos - rd), "unknown RD format");
806 break;
807 }
808 pos += strlen(pos);
809 *(pos) = '\0';
810 return (rd);
811 }
812
813 /*
814 * Print an RFC 4360 Extended Community.
815 */
816 static void
817 bgp_extended_community_print(netdissect_options *ndo,
818 const u_char *pptr)
819 {
820 union { /* copy buffer for bandwidth values */
821 float f;
822 uint32_t i;
823 } bw;
824
825 switch (GET_BE_U_2(pptr)) {
826
827 case BGP_EXT_COM_RT_0:
828 case BGP_EXT_COM_RO_0:
829 case BGP_EXT_COM_L2VPN_RT_0:
830 ND_PRINT("%u:%u (= %s)",
831 GET_BE_U_2(pptr + 2),
832 GET_BE_U_4(pptr + 4),
833 GET_IPADDR_STRING(pptr+4));
834 break;
835
836 case BGP_EXT_COM_RT_1:
837 case BGP_EXT_COM_RO_1:
838 case BGP_EXT_COM_L2VPN_RT_1:
839 case BGP_EXT_COM_VRF_RT_IMP:
840 ND_PRINT("%s:%u",
841 GET_IPADDR_STRING(pptr+2),
842 GET_BE_U_2(pptr + 6));
843 break;
844
845 case BGP_EXT_COM_RT_2:
846 case BGP_EXT_COM_RO_2:
847 ND_PRINT("%s:%u",
848 as_printf(ndo, astostr, sizeof(astostr),
849 GET_BE_U_4(pptr + 2)), GET_BE_U_2(pptr + 6));
850 break;
851
852 case BGP_EXT_COM_LINKBAND:
853 bw.i = GET_BE_U_4(pptr + 2);
854 ND_PRINT("bandwidth: %.3f Mbps",
855 bw.f*8/1000000);
856 break;
857
858 case BGP_EXT_COM_VPN_ORIGIN:
859 case BGP_EXT_COM_VPN_ORIGIN2:
860 case BGP_EXT_COM_VPN_ORIGIN3:
861 case BGP_EXT_COM_VPN_ORIGIN4:
862 case BGP_EXT_COM_OSPF_RID:
863 case BGP_EXT_COM_OSPF_RID2:
864 ND_PRINT("%s", GET_IPADDR_STRING(pptr+2));
865 break;
866
867 case BGP_EXT_COM_OSPF_RTYPE:
868 case BGP_EXT_COM_OSPF_RTYPE2:
869 ND_PRINT("area:%s, router-type:%s, metric-type:%s%s",
870 GET_IPADDR_STRING(pptr+2),
871 tok2str(bgp_extd_comm_ospf_rtype_values,
872 "unknown (0x%02x)",
873 GET_U_1((pptr + 6))),
874 (GET_U_1(pptr + 7) & BGP_OSPF_RTYPE_METRIC_TYPE) ? "E2" : "",
875 ((GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_EXT) || (GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_NSSA)) ? "E1" : "");
876 break;
877
878 case BGP_EXT_COM_L2INFO:
879 ND_PRINT("%s Control Flags [0x%02x]:MTU %u",
880 tok2str(l2vpn_encaps_values,
881 "unknown encaps",
882 GET_U_1((pptr + 2))),
883 GET_U_1((pptr + 3)),
884 GET_BE_U_2(pptr + 4));
885 break;
886
887 case BGP_EXT_COM_SOURCE_AS:
888 ND_PRINT("AS %u", GET_BE_U_2(pptr + 2));
889 break;
890
891 case BGP_EXT_COM_ENCAP:
892 ND_PRINT("Tunnel type: %s", tok2str(bgp_extd_comm_encap_tunnel_values,
893 "unknown encaps",
894 GET_BE_U_2(pptr + 6)));
895 break;
896
897 default:
898 ND_PRINT("%02x%02x%02x%02x%02x%02x",
899 GET_U_1(pptr + 2),
900 GET_U_1(pptr + 3),
901 GET_U_1(pptr + 4),
902 GET_U_1(pptr + 5),
903 GET_U_1(pptr + 6),
904 GET_U_1(pptr + 7));
905 break;
906 }
907 }
908
909 /*
910 * RFC4684 (Section 4)/RFC2858 (Section 4).
911 * RTC membership prefix is structured as follows
912 * [prefix-len] [origin-as] [route-target]
913 * The route-target is encoded as RT ext-comms.
914 * Prefix-len may be 0, 32..96
915 *
916 * Note that pptr is not packet data - it is
917 * a buffer owned by our caller - therefore GET_*
918 * macros can not be used.
919 */
920 static char *
921 bgp_rt_prefix_print(netdissect_options *ndo,
922 const u_char *pptr,
923 u_int plen)
924 {
925 /* allocate space for the largest possible string */
926 char rtc_prefix_in_hex[20] = "";
927 u_int rtc_prefix_in_hex_len = 0;
928 static char output[61]; /* max response string */
929 uint16_t ec_type = 0;
930 u_int octet_count;
931 u_int i;
932
933 if (plen == 0) {
934 snprintf(output, sizeof(output), "route-target: 0:0/0");
935 return (output);
936 }
937
938 /* hex representation of the prefix */
939 octet_count = (plen+7)/8;
940 for (i=0; i<octet_count; i++) {
941 rtc_prefix_in_hex_len += snprintf(rtc_prefix_in_hex+rtc_prefix_in_hex_len,
942 sizeof(rtc_prefix_in_hex)-rtc_prefix_in_hex_len,
943 "%02x%s", *(pptr+i),
944 ((i%2 == 1) && (i<octet_count-1)) ? " " : "");
945 }
946
947 if (plen < 16) {
948 /*
949 * The prefix is too short to include the full ext-comm type,
950 * so we have no way to parse it further.
951 */
952 snprintf(output, sizeof(output), "route-target: partial-type: (%s/%d)",
953 rtc_prefix_in_hex, plen);
954 return (output);
955 }
956
957 /*
958 * get the ext-comm type
959 * Note: pptr references a static 8 octet buffer with unused bits set to 0,
960 * hense EXTRACT_*() macros are safe.
961 */
962 ec_type = EXTRACT_BE_U_2(pptr);
963 switch (ec_type) {
964 case BGP_EXT_COM_RT_0:
965 /* 2-byte-AS:number fmt */
966 snprintf(output, sizeof(output), "route-target: %u:%u/%d (%s)",
967 EXTRACT_BE_U_2(pptr+2),
968 EXTRACT_BE_U_4(pptr+4),
969 plen, rtc_prefix_in_hex);
970 break;
971
972 case BGP_EXT_COM_RT_1:
973 /* IP-address:AS fmt */
974 snprintf(output, sizeof(output), "route-target: %u.%u.%u.%u:%u/%d (%s)",
975 *(pptr+2), *(pptr+3), *(pptr+4), *(pptr+5),
976 EXTRACT_BE_U_2(pptr+6), plen, rtc_prefix_in_hex);
977 break;
978
979 case BGP_EXT_COM_RT_2:
980 /* 4-byte-AS:number fmt */
981 snprintf(output, sizeof(output), "route-target: %s:%u/%d (%s)",
982 as_printf(ndo, astostr, sizeof(astostr), EXTRACT_BE_U_4(pptr+2)),
983 EXTRACT_BE_U_2(pptr+6), plen, rtc_prefix_in_hex);
984 break;
985
986 default:
987 snprintf(output, sizeof(output), "route target: unknown-type(%04x) (%s/%d)",
988 ec_type,
989 rtc_prefix_in_hex, plen);
990 break;
991 }
992 return (output);
993 }
994
995 /* RFC 4684 */
996 static int
997 decode_rt_routing_info(netdissect_options *ndo,
998 const u_char *pptr)
999 {
1000 uint8_t route_target[8];
1001 u_int plen;
1002 char asbuf[sizeof(astostr)]; /* bgp_vpn_rd_print() overwrites astostr */
1003 u_int num_octets;
1004
1005 /* NLRI "prefix length" from RFC 2858 Section 4. */
1006 ND_TCHECK_1(pptr);
1007 plen = GET_U_1(pptr); /* get prefix length */
1008
1009 /* NLRI "prefix" (ibid), valid lengths are { 0, 32, 33, ..., 96 } bits.
1010 * RFC 4684 Section 4 defines the layout of "origin AS" and "route
1011 * target" fields inside the "prefix" depending on its length.
1012 */
1013 if (0 == plen) {
1014 /* Without "origin AS", without "route target". */
1015 ND_PRINT("\n\t default route target");
1016 return 1;
1017 }
1018
1019 if (32 > plen) {
1020 ND_PRINT("\n\t (illegal prefix length)");
1021 return -1;
1022 }
1023
1024 /* With at least "origin AS", possibly with "route target". */
1025 ND_TCHECK_4(pptr + 1);
1026 as_printf(ndo, asbuf, sizeof(asbuf), GET_BE_U_4(pptr + 1));
1027
1028 plen -= 32; /* adjust prefix length */
1029
1030 if (64 < plen) {
1031 ND_PRINT("\n\t (illegal prefix length)");
1032 return -1;
1033 }
1034
1035 /* From now on (plen + 7) / 8 evaluates to { 0, 1, 2, ..., 8 }
1036 * and gives the number of octets in the variable-length "route
1037 * target" field inside this NLRI "prefix". Look for it.
1038 */
1039 memset(&route_target, 0, sizeof(route_target));
1040 num_octets = (plen + 7) / 8;
1041 ND_TCHECK_LEN(pptr + 5, num_octets);
1042 memcpy(&route_target, pptr + 5, num_octets);
1043 /* If mask-len is not on octet boundary, ensure all extra bits are 0 */
1044 if (plen % 8) {
1045 ((u_char *)&route_target)[num_octets - 1] &=
1046 ((0xff00 >> (plen % 8)) & 0xff);
1047 }
1048 ND_PRINT("\n\t origin AS: %s, %s",
1049 asbuf,
1050 bgp_rt_prefix_print(ndo, (u_char *)&route_target, plen));
1051
1052 return 5 + num_octets;
1053 trunc:
1054 return -2;
1055 }
1056
1057 static int
1058 decode_labeled_vpn_prefix4(netdissect_options *ndo,
1059 const u_char *pptr, char *buf, size_t buflen)
1060 {
1061 nd_ipv4 addr;
1062 u_int plen;
1063
1064 ND_TCHECK_1(pptr);
1065 plen = GET_U_1(pptr); /* get prefix length */
1066
1067 if ((24+64) > plen)
1068 return -1;
1069
1070 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1071
1072 if (32 < plen)
1073 return -1;
1074
1075 memset(&addr, 0, sizeof(addr));
1076 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1077 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1078 if (plen % 8) {
1079 ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
1080 ((0xff00 >> (plen % 8)) & 0xff);
1081 }
1082 /* the label may get offsetted by 4 bits so lets shift it right */
1083 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1084 bgp_vpn_rd_print(ndo, pptr+4),
1085 ipaddr_string(ndo, (const u_char *)&addr),
1086 plen,
1087 GET_BE_U_3(pptr + 1)>>4,
1088 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1089
1090 return 12 + (plen + 7) / 8;
1091
1092 trunc:
1093 return -2;
1094 }
1095
1096 /*
1097 * +-------------------------------+
1098 * | |
1099 * | RD:IPv4-address (12 octets) |
1100 * | |
1101 * +-------------------------------+
1102 * | MDT Group-address (4 octets) |
1103 * +-------------------------------+
1104 */
1105
1106 #define MDT_VPN_NLRI_LEN 16
1107
1108 static int
1109 decode_mdt_vpn_nlri(netdissect_options *ndo,
1110 const u_char *pptr, char *buf, size_t buflen)
1111 {
1112 const u_char *rd;
1113 const u_char *vpn_ip;
1114
1115 ND_TCHECK_1(pptr);
1116
1117 /* if the NLRI is not predefined length, quit.*/
1118 if (GET_U_1(pptr) != MDT_VPN_NLRI_LEN * 8)
1119 return -1;
1120 pptr++;
1121
1122 /* RD */
1123 ND_TCHECK_8(pptr);
1124 rd = pptr;
1125 pptr += 8;
1126
1127 /* IPv4 address */
1128 ND_TCHECK_LEN(pptr, sizeof(nd_ipv4));
1129 vpn_ip = pptr;
1130 pptr += sizeof(nd_ipv4);
1131
1132 /* MDT Group Address */
1133 ND_TCHECK_LEN(pptr, sizeof(nd_ipv4));
1134
1135 snprintf(buf, buflen, "RD: %s, VPN IP Address: %s, MC Group Address: %s",
1136 bgp_vpn_rd_print(ndo, rd), GET_IPADDR_STRING(vpn_ip), GET_IPADDR_STRING(pptr));
1137
1138 return MDT_VPN_NLRI_LEN + 1;
1139
1140 trunc:
1141 return -2;
1142 }
1143
1144 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI 1
1145 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI 2
1146 #define BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI 3
1147 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF 4
1148 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE 5
1149 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN 6
1150 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN 7
1151
1152 static const struct tok bgp_multicast_vpn_route_type_values[] = {
1153 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI, "Intra-AS I-PMSI"},
1154 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI, "Inter-AS I-PMSI"},
1155 { BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI, "S-PMSI"},
1156 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF, "Intra-AS Segment-Leaf"},
1157 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE, "Source-Active"},
1158 { BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN, "Shared Tree Join"},
1159 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN, "Source Tree Join"},
1160 { 0, NULL}
1161 };
1162
1163 static int
1164 decode_multicast_vpn(netdissect_options *ndo,
1165 const u_char *pptr, char *buf, size_t buflen)
1166 {
1167 uint8_t route_type, route_length;
1168 u_int addr_length, sg_length;
1169 u_int offset;
1170
1171 ND_TCHECK_2(pptr);
1172 route_type = GET_U_1(pptr);
1173 pptr++;
1174 route_length = GET_U_1(pptr);
1175 pptr++;
1176
1177 snprintf(buf, buflen, "Route-Type: %s (%u), length: %u",
1178 tok2str(bgp_multicast_vpn_route_type_values,
1179 "Unknown", route_type),
1180 route_type, route_length);
1181
1182 switch(route_type) {
1183 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI:
1184 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1185 offset = (u_int)strlen(buf);
1186 snprintf(buf + offset, buflen - offset, ", RD: %s, Originator %s",
1187 bgp_vpn_rd_print(ndo, pptr),
1188 bgp_vpn_ip_print(ndo, pptr + BGP_VPN_RD_LEN,
1189 (route_length - BGP_VPN_RD_LEN) << 3));
1190 break;
1191 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI:
1192 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1193 offset = (u_int)strlen(buf);
1194 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1195 bgp_vpn_rd_print(ndo, pptr),
1196 as_printf(ndo, astostr, sizeof(astostr),
1197 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1198 break;
1199
1200 case BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI:
1201 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1202 offset = (u_int)strlen(buf);
1203 snprintf(buf + offset, buflen - offset, ", RD: %s",
1204 bgp_vpn_rd_print(ndo, pptr));
1205 pptr += BGP_VPN_RD_LEN;
1206
1207 sg_length = bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1208 addr_length = route_length - sg_length;
1209
1210 ND_TCHECK_LEN(pptr, addr_length);
1211 offset = (u_int)strlen(buf);
1212 snprintf(buf + offset, buflen - offset, ", Originator %s",
1213 bgp_vpn_ip_print(ndo, pptr, addr_length << 3));
1214 break;
1215
1216 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE:
1217 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1218 offset = (u_int)strlen(buf);
1219 snprintf(buf + offset, buflen - offset, ", RD: %s",
1220 bgp_vpn_rd_print(ndo, pptr));
1221 pptr += BGP_VPN_RD_LEN;
1222
1223 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1224 break;
1225
1226 case BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN: /* fall through */
1227 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN:
1228 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1229 offset = (u_int)strlen(buf);
1230 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1231 bgp_vpn_rd_print(ndo, pptr),
1232 as_printf(ndo, astostr, sizeof(astostr),
1233 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1234 pptr += BGP_VPN_RD_LEN + 4;
1235
1236 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1237 break;
1238
1239 /*
1240 * no per route-type printing yet.
1241 */
1242 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF:
1243 default:
1244 break;
1245 }
1246
1247 return route_length + 2;
1248
1249 trunc:
1250 return -2;
1251 }
1252
1253 /*
1254 * As I remember, some versions of systems have an snprintf() that
1255 * returns -1 if the buffer would have overflowed. If the return
1256 * value is negative, set buflen to 0, to indicate that we've filled
1257 * the buffer up.
1258 *
1259 * If the return value is greater than buflen, that means that
1260 * the buffer would have overflowed; again, set buflen to 0 in
1261 * that case.
1262 */
1263 #define UPDATE_BUF_BUFLEN(buf, buflen, stringlen) \
1264 if (stringlen<0) \
1265 buflen=0; \
1266 else if ((u_int)stringlen>buflen) \
1267 buflen=0; \
1268 else { \
1269 buflen-=stringlen; \
1270 buf+=stringlen; \
1271 }
1272
1273 static int
1274 decode_labeled_vpn_l2(netdissect_options *ndo,
1275 const u_char *pptr, char *buf, size_t buflen)
1276 {
1277 u_int plen, tlen, tlv_type, tlv_len, ttlv_len;
1278 int stringlen;
1279
1280 ND_TCHECK_2(pptr);
1281 plen = GET_BE_U_2(pptr);
1282 tlen = plen;
1283 pptr += 2;
1284 /* Old and new L2VPN NLRI share AFI/SAFI
1285 * -> Assume a 12 Byte-length NLRI is auto-discovery-only
1286 * and > 17 as old format. Complain for the middle case
1287 */
1288 if (plen == 12) {
1289 /* assume AD-only with RD, BGPNH */
1290 ND_TCHECK_LEN(pptr, 12);
1291 buf[0] = '\0';
1292 stringlen = snprintf(buf, buflen, "RD: %s, BGPNH: %s",
1293 bgp_vpn_rd_print(ndo, pptr),
1294 GET_IPADDR_STRING(pptr+8));
1295 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1296 pptr += 12;
1297 tlen -= 12;
1298 return plen + 2;
1299 } else if (plen > 17) {
1300 /* assume old format */
1301 /* RD, ID, LBLKOFF, LBLBASE */
1302
1303 ND_TCHECK_LEN(pptr, 15);
1304 buf[0] = '\0';
1305 stringlen = snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u",
1306 bgp_vpn_rd_print(ndo, pptr),
1307 GET_BE_U_2(pptr + 8),
1308 GET_BE_U_2(pptr + 10),
1309 GET_BE_U_3(pptr + 12)>>4); /* the label is offsetted by 4 bits so lets shift it right */
1310 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1311 pptr += 15;
1312 tlen -= 15;
1313
1314 /* ok now the variable part - lets read out TLVs*/
1315 while (tlen != 0) {
1316 if (tlen < 3) {
1317 if (buflen != 0) {
1318 stringlen=snprintf(buf,buflen, "\n\t\tran past the end");
1319 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1320 }
1321 return plen + 2;
1322 }
1323 ND_TCHECK_3(pptr);
1324 tlv_type = GET_U_1(pptr);
1325 pptr++;
1326 tlv_len = GET_BE_U_2(pptr); /* length, in *bits* */
1327 ttlv_len = (tlv_len + 7)/8; /* length, in *bytes* */
1328 pptr += 2;
1329
1330 switch(tlv_type) {
1331 case 1:
1332 if (buflen != 0) {
1333 stringlen=snprintf(buf,buflen, "\n\t\tcircuit status vector (%u) length: %u: 0x",
1334 tlv_type,
1335 tlv_len);
1336 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1337 }
1338 while (ttlv_len != 0) {
1339 if (tlen < 1) {
1340 if (buflen != 0) {
1341 stringlen=snprintf(buf,buflen, " (ran past the end)");
1342 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1343 }
1344 return plen + 2;
1345 }
1346 ND_TCHECK_1(pptr);
1347 if (buflen != 0) {
1348 stringlen=snprintf(buf,buflen, "%02x",
1349 GET_U_1(pptr));
1350 pptr++;
1351 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1352 }
1353 ttlv_len--;
1354 tlen--;
1355 }
1356 break;
1357 default:
1358 if (buflen != 0) {
1359 stringlen=snprintf(buf,buflen, "\n\t\tunknown TLV #%u, length: %u",
1360 tlv_type,
1361 tlv_len);
1362 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1363 }
1364 if (tlen < ttlv_len) {
1365 if (buflen != 0) {
1366 stringlen=snprintf(buf,buflen, " (ran past the end)");
1367 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1368 }
1369 return plen + 2;
1370 }
1371 tlen -= ttlv_len;
1372 break;
1373 }
1374 }
1375 return plen + 2;
1376 } else {
1377 /* complain bitterly ? */
1378 /* fall through */
1379 goto trunc;
1380 }
1381
1382 trunc:
1383 return -2;
1384 }
1385
1386 int
1387 decode_prefix6(netdissect_options *ndo,
1388 const u_char *pd, u_int itemlen, char *buf, size_t buflen)
1389 {
1390 nd_ipv6 addr;
1391 u_int plen, plenbytes;
1392
1393 ND_TCHECK_1(pd);
1394 ITEMCHECK(1);
1395 plen = GET_U_1(pd);
1396 if (128 < plen)
1397 return -1;
1398 itemlen -= 1;
1399
1400 memset(&addr, 0, sizeof(addr));
1401 plenbytes = (plen + 7) / 8;
1402 ND_TCHECK_LEN(pd + 1, plenbytes);
1403 ITEMCHECK(plenbytes);
1404 memcpy(&addr, pd + 1, plenbytes);
1405 if (plen % 8) {
1406 addr[plenbytes - 1] &=
1407 ((0xff00 >> (plen % 8)) & 0xff);
1408 }
1409 snprintf(buf, buflen, "%s/%u", ip6addr_string(ndo, (const u_char *)&addr), plen);
1410 return 1 + plenbytes;
1411
1412 trunc:
1413 return -2;
1414
1415 badtlv:
1416 return -3;
1417 }
1418
1419 static int
1420 decode_labeled_prefix6(netdissect_options *ndo,
1421 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
1422 {
1423 nd_ipv6 addr;
1424 u_int plen, plenbytes;
1425
1426 /* prefix length and label = 4 bytes */
1427 ND_TCHECK_4(pptr);
1428 ITEMCHECK(4);
1429 plen = GET_U_1(pptr); /* get prefix length */
1430
1431 if (24 > plen)
1432 return -1;
1433
1434 plen -= 24; /* adjust prefixlen - labellength */
1435
1436 if (128 < plen)
1437 return -1;
1438 itemlen -= 4;
1439
1440 memset(&addr, 0, sizeof(addr));
1441 plenbytes = (plen + 7) / 8;
1442 ND_TCHECK_LEN(pptr + 4, plenbytes);
1443 memcpy(&addr, pptr + 4, plenbytes);
1444 if (plen % 8) {
1445 addr[plenbytes - 1] &=
1446 ((0xff00 >> (plen % 8)) & 0xff);
1447 }
1448 /* the label may get offsetted by 4 bits so lets shift it right */
1449 snprintf(buf, buflen, "%s/%u, label:%u %s",
1450 ip6addr_string(ndo, (const u_char *)&addr),
1451 plen,
1452 GET_BE_U_3(pptr + 1)>>4,
1453 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1454
1455 return 4 + plenbytes;
1456
1457 trunc:
1458 return -2;
1459
1460 badtlv:
1461 return -3;
1462 }
1463
1464 static int
1465 decode_labeled_vpn_prefix6(netdissect_options *ndo,
1466 const u_char *pptr, char *buf, size_t buflen)
1467 {
1468 nd_ipv6 addr;
1469 u_int plen;
1470
1471 ND_TCHECK_1(pptr);
1472 plen = GET_U_1(pptr); /* get prefix length */
1473
1474 if ((24+64) > plen)
1475 return -1;
1476
1477 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1478
1479 if (128 < plen)
1480 return -1;
1481
1482 memset(&addr, 0, sizeof(addr));
1483 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1484 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1485 if (plen % 8) {
1486 addr[(plen + 7) / 8 - 1] &=
1487 ((0xff00 >> (plen % 8)) & 0xff);
1488 }
1489 /* the label may get offsetted by 4 bits so lets shift it right */
1490 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1491 bgp_vpn_rd_print(ndo, pptr+4),
1492 ip6addr_string(ndo, (const u_char *)&addr),
1493 plen,
1494 GET_BE_U_3(pptr + 1)>>4,
1495 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1496
1497 return 12 + (plen + 7) / 8;
1498
1499 trunc:
1500 return -2;
1501 }
1502
1503 static int
1504 decode_clnp_prefix(netdissect_options *ndo,
1505 const u_char *pptr, char *buf, size_t buflen)
1506 {
1507 uint8_t addr[19];
1508 u_int plen;
1509
1510 ND_TCHECK_1(pptr);
1511 plen = GET_U_1(pptr); /* get prefix length */
1512
1513 if (152 < plen)
1514 return -1;
1515
1516 memset(&addr, 0, sizeof(addr));
1517 ND_TCHECK_LEN(pptr + 4, (plen + 7) / 8);
1518 memcpy(&addr, pptr + 4, (plen + 7) / 8);
1519 if (plen % 8) {
1520 addr[(plen + 7) / 8 - 1] &=
1521 ((0xff00 >> (plen % 8)) & 0xff);
1522 }
1523 snprintf(buf, buflen, "%s/%u",
1524 isonsap_string(ndo, addr,(plen + 7) / 8),
1525 plen);
1526
1527 return 1 + (plen + 7) / 8;
1528
1529 trunc:
1530 return -2;
1531 }
1532
1533 static int
1534 decode_labeled_vpn_clnp_prefix(netdissect_options *ndo,
1535 const u_char *pptr, char *buf, size_t buflen)
1536 {
1537 uint8_t addr[19];
1538 u_int plen;
1539
1540 ND_TCHECK_1(pptr);
1541 plen = GET_U_1(pptr); /* get prefix length */
1542
1543 if ((24+64) > plen)
1544 return -1;
1545
1546 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1547
1548 if (152 < plen)
1549 return -1;
1550
1551 memset(&addr, 0, sizeof(addr));
1552 ND_TCHECK_LEN(pptr + 12, (plen + 7) / 8);
1553 memcpy(&addr, pptr + 12, (plen + 7) / 8);
1554 if (plen % 8) {
1555 addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
1556 }
1557 /* the label may get offsetted by 4 bits so lets shift it right */
1558 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1559 bgp_vpn_rd_print(ndo, pptr+4),
1560 isonsap_string(ndo, addr,(plen + 7) / 8),
1561 plen,
1562 GET_BE_U_3(pptr + 1)>>4,
1563 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1564
1565 return 12 + (plen + 7) / 8;
1566
1567 trunc:
1568 return -2;
1569 }
1570
1571 /*
1572 * bgp_attr_get_as_size
1573 *
1574 * Try to find the size of the ASs encoded in an as-path. It is not obvious, as
1575 * both Old speakers that do not support 4 byte AS, and the new speakers that do
1576 * support, exchange AS-Path with the same path-attribute type value 0x02.
1577 */
1578 static u_int
1579 bgp_attr_get_as_size(netdissect_options *ndo,
1580 uint8_t bgpa_type, const u_char *pptr, u_int len)
1581 {
1582 const u_char *tptr = pptr;
1583
1584 /*
1585 * If the path attribute is the optional AS4 path type, then we already
1586 * know, that ASs must be encoded in 4 byte format.
1587 */
1588 if (bgpa_type == BGPTYPE_AS4_PATH) {
1589 return 4;
1590 }
1591
1592 /*
1593 * Let us assume that ASs are of 2 bytes in size, and check if the AS-Path
1594 * TLV is good. If not, ask the caller to try with AS encoded as 4 bytes
1595 * each.
1596 */
1597 while (tptr < pptr + len) {
1598 ND_TCHECK_1(tptr);
1599
1600 /*
1601 * If we do not find a valid segment type, our guess might be wrong.
1602 */
1603 if (GET_U_1(tptr) < BGP_AS_SEG_TYPE_MIN || GET_U_1(tptr) > BGP_AS_SEG_TYPE_MAX) {
1604 goto trunc;
1605 }
1606 ND_TCHECK_1(tptr + 1);
1607 tptr += 2 + GET_U_1(tptr + 1) * 2;
1608 }
1609
1610 /*
1611 * If we correctly reached end of the AS path attribute data content,
1612 * then most likely ASs were indeed encoded as 2 bytes.
1613 */
1614 if (tptr == pptr + len) {
1615 return 2;
1616 }
1617
1618 trunc:
1619
1620 /*
1621 * We can come here, either we did not have enough data, or if we
1622 * try to decode 4 byte ASs in 2 byte format. Either way, return 4,
1623 * so that calller can try to decode each AS as of 4 bytes. If indeed
1624 * there was not enough data, it will crib and end the parse anyways.
1625 */
1626 return 4;
1627 }
1628
1629 /*
1630 * The only way to know that a BGP UPDATE message is using add path is
1631 * by checking if the capability is in the OPEN message which we may have missed.
1632 * So this function checks if it is possible that the update could contain add path
1633 * and if so it checks that standard BGP doesn't make sense.
1634 */
1635 static int
1636 check_add_path(netdissect_options *ndo, const u_char *pptr, u_int length,
1637 u_int max_prefix_length)
1638 {
1639 u_int offset, prefix_length;
1640
1641 if (length < 5) {
1642 return 0;
1643 }
1644
1645 /*
1646 * Scan through the NLRI information under the assumpetion that
1647 * it doesn't have path IDs.
1648 */
1649 for (offset = 0; offset < length;) {
1650 offset += 4;
1651 if (!ND_TTEST_1(pptr + offset)) {
1652 /* We ran out of captured data; quit scanning. */
1653 break;
1654 }
1655 prefix_length = GET_U_1(pptr + offset);
1656 /*
1657 * Add 4 to cover the path id
1658 * and check the prefix length isn't greater than 32/128.
1659 */
1660 if (prefix_length > max_prefix_length) {
1661 return 0;
1662 }
1663 /* Add 1 for the prefix_length byte and prefix_length to cover the address */
1664 offset += 1 + ((prefix_length + 7) / 8);
1665 }
1666 /* check we haven't gone past the end of the section */
1667 if (offset > length) {
1668 return 0;
1669 }
1670
1671 /* check it's not standard BGP */
1672 for (offset = 0; offset < length; ) {
1673 if (!ND_TTEST_1(pptr + offset)) {
1674 /* We ran out of captured data; quit scanning. */
1675 break;
1676 }
1677 prefix_length = GET_U_1(pptr + offset);
1678 /*
1679 * If the prefix_length is zero (0.0.0.0/0)
1680 * and since it's not the only address (length >= 5)
1681 * then it is add-path
1682 */
1683 if (prefix_length < 1 || prefix_length > max_prefix_length) {
1684 return 1;
1685 }
1686 offset += 1 + ((prefix_length + 7) / 8);
1687 }
1688 if (offset > length) {
1689 return 1;
1690 }
1691
1692 /* assume not add-path by default */
1693 return 0;
1694 }
1695
1696 static int
1697 bgp_mp_af_print(netdissect_options *ndo,
1698 const u_char *tptr, u_int tlen,
1699 uint16_t *afp, uint8_t *safip)
1700 {
1701 uint16_t af;
1702 uint8_t safi;
1703
1704 af = GET_BE_U_2(tptr);
1705 *afp = af;
1706 safi = GET_U_1(tptr + 2);
1707 *safip = safi;
1708
1709 ND_PRINT("\n\t AFI: %s (%u), %sSAFI: %s (%u)",
1710 tok2str(af_values, "Unknown AFI", af),
1711 af,
1712 (safi>128) ? "vendor specific " : "", /* 128 is meanwhile wellknown */
1713 tok2str(bgp_safi_values, "Unknown SAFI", safi),
1714 safi);
1715
1716 switch(af<<8 | safi) {
1717 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1718 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1719 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1720 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1721 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1722 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1723 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1724 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1725 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
1726 case (AFNUM_INET<<8 | SAFNUM_MDT):
1727 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1728 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1729 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1730 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1731 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1732 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1733 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1734 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1735 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1736 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1737 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1738 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1739 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1740 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1741 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1742 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1743 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1744 break;
1745 default:
1746 ND_TCHECK_LEN(tptr, tlen);
1747 ND_PRINT("\n\t no AFI %u / SAFI %u decoder", af, safi);
1748 if (ndo->ndo_vflag <= 1)
1749 print_unknown_data(ndo, tptr, "\n\t ", tlen);
1750 return -1;
1751 }
1752 return 0;
1753 trunc:
1754 return -2;
1755 }
1756
1757 static int
1758 bgp_nlri_print(netdissect_options *ndo, uint16_t af, uint8_t safi,
1759 const u_char *tptr, u_int len,
1760 char *buf, size_t buflen,
1761 int add_path4, int add_path6)
1762 {
1763 int advance;
1764 u_int path_id = 0;
1765
1766 switch (af<<8 | safi) {
1767 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1768 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1769 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1770 if (add_path4) {
1771 path_id = GET_BE_U_4(tptr);
1772 tptr += 4;
1773 }
1774 advance = decode_prefix4(ndo, tptr, len, buf, buflen);
1775 if (advance == -1)
1776 ND_PRINT("\n\t (illegal prefix length)");
1777 else if (advance == -2)
1778 goto trunc;
1779 else if (advance == -3)
1780 break; /* bytes left, but not enough */
1781 else
1782 ND_PRINT("\n\t %s", buf);
1783 if (add_path4) {
1784 ND_PRINT(" Path Id: %u", path_id);
1785 advance += 4;
1786 }
1787 break;
1788 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1789 advance = decode_labeled_prefix4(ndo, tptr, len, buf, buflen);
1790 if (advance == -1)
1791 ND_PRINT("\n\t (illegal prefix length)");
1792 else if (advance == -2)
1793 goto trunc;
1794 else if (advance == -3)
1795 break; /* bytes left, but not enough */
1796 else
1797 ND_PRINT("\n\t %s", buf);
1798 break;
1799 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1800 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1801 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1802 advance = decode_labeled_vpn_prefix4(ndo, tptr, buf, buflen);
1803 if (advance == -1)
1804 ND_PRINT("\n\t (illegal prefix length)");
1805 else if (advance == -2)
1806 goto trunc;
1807 else
1808 ND_PRINT("\n\t %s", buf);
1809 break;
1810 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1811 advance = decode_rt_routing_info(ndo, tptr);
1812 if (advance == -2)
1813 goto trunc;
1814 break;
1815 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN): /* fall through */
1816 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST_VPN):
1817 advance = decode_multicast_vpn(ndo, tptr, buf, buflen);
1818 if (advance == -1)
1819 ND_PRINT("\n\t (illegal prefix length)");
1820 else if (advance == -2)
1821 goto trunc;
1822 else
1823 ND_PRINT("\n\t %s", buf);
1824 break;
1825
1826 case (AFNUM_INET<<8 | SAFNUM_MDT):
1827 advance = decode_mdt_vpn_nlri(ndo, tptr, buf, buflen);
1828 if (advance == -1)
1829 ND_PRINT("\n\t (illegal prefix length)");
1830 else if (advance == -2)
1831 goto trunc;
1832 else
1833 ND_PRINT("\n\t %s", buf);
1834 break;
1835 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1836 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1837 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1838 if (add_path6) {
1839 path_id = GET_BE_U_4(tptr);
1840 tptr += 4;
1841 }
1842 advance = decode_prefix6(ndo, tptr, len, buf, buflen);
1843 if (advance == -1)
1844 ND_PRINT("\n\t (illegal prefix length)");
1845 else if (advance == -2)
1846 goto trunc;
1847 else if (advance == -3)
1848 break; /* bytes left, but not enough */
1849 else
1850 ND_PRINT("\n\t %s", buf);
1851 if (add_path6) {
1852 ND_PRINT(" Path Id: %u", path_id);
1853 advance += 4;
1854 }
1855 break;
1856 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1857 advance = decode_labeled_prefix6(ndo, tptr, len, buf, buflen);
1858 if (advance == -1)
1859 ND_PRINT("\n\t (illegal prefix length)");
1860 else if (advance == -2)
1861 goto trunc;
1862 else if (advance == -3)
1863 break; /* bytes left, but not enough */
1864 else
1865 ND_PRINT("\n\t %s", buf);
1866 break;
1867 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1868 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1869 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1870 advance = decode_labeled_vpn_prefix6(ndo, tptr, buf, buflen);
1871 if (advance == -1)
1872 ND_PRINT("\n\t (illegal prefix length)");
1873 else if (advance == -2)
1874 goto trunc;
1875 else
1876 ND_PRINT("\n\t %s", buf);
1877 break;
1878 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1879 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1880 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1881 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1882 advance = decode_labeled_vpn_l2(ndo, tptr, buf, buflen);
1883 if (advance == -1)
1884 ND_PRINT("\n\t (illegal length)");
1885 else if (advance == -2)
1886 goto trunc;
1887 else
1888 ND_PRINT("\n\t %s", buf);
1889 break;
1890 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1891 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1892 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1893 advance = decode_clnp_prefix(ndo, tptr, buf, buflen);
1894 if (advance == -1)
1895 ND_PRINT("\n\t (illegal prefix length)");
1896 else if (advance == -2)
1897 goto trunc;
1898 else
1899 ND_PRINT("\n\t %s", buf);
1900 break;
1901 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1902 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1903 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1904 advance = decode_labeled_vpn_clnp_prefix(ndo, tptr, buf, buflen);
1905 if (advance == -1)
1906 ND_PRINT("\n\t (illegal prefix length)");
1907 else if (advance == -2)
1908 goto trunc;
1909 else
1910 ND_PRINT("\n\t %s", buf);
1911 break;
1912 default:
1913 /*
1914 * This should not happen, we should have been protected
1915 * by bgp_mp_af_print()'s return value.
1916 */
1917 ND_PRINT("\n\t ERROR: no AFI %u / SAFI %u decoder", af, safi);
1918 advance = -4;
1919 break;
1920 }
1921 return advance;
1922 trunc: /* we rely on the caller to recognize -2 return value */
1923 return -2;
1924 }
1925
1926 static int
1927 bgp_attr_print(netdissect_options *ndo,
1928 uint8_t atype, const u_char *pptr, u_int len,
1929 const unsigned attr_set_level)
1930 {
1931 u_int i;
1932 uint16_t af;
1933 uint8_t safi, snpa, nhlen;
1934 int advance;
1935 u_int tlen;
1936 const u_char *tptr;
1937 char buf[MAXHOSTNAMELEN + 100];
1938 u_int as_size;
1939 int add_path4, add_path6;
1940 int ret;
1941
1942 tptr = pptr;
1943 tlen = len;
1944
1945 switch (atype) {
1946 case BGPTYPE_ORIGIN:
1947 if (len != 1)
1948 ND_PRINT("invalid len");
1949 else {
1950 ND_TCHECK_1(tptr);
1951 ND_PRINT("%s", tok2str(bgp_origin_values,
1952 "Unknown Origin Typecode",
1953 GET_U_1(tptr)));
1954 }
1955 break;
1956
1957 /*
1958 * Process AS4 byte path and AS2 byte path attributes here.
1959 */
1960 case BGPTYPE_AS4_PATH:
1961 case BGPTYPE_AS_PATH:
1962 if (len % 2) {
1963 ND_PRINT("invalid len");
1964 break;
1965 }
1966 if (!len) {
1967 ND_PRINT("empty");
1968 break;
1969 }
1970
1971 /*
1972 * BGP updates exchanged between New speakers that support 4
1973 * byte AS, ASs are always encoded in 4 bytes. There is no
1974 * definitive way to find this, just by the packet's
1975 * contents. So, check for packet's TLV's sanity assuming
1976 * 2 bytes first, and it does not pass, assume that ASs are
1977 * encoded in 4 bytes format and move on.
1978 */
1979 as_size = bgp_attr_get_as_size(ndo, atype, pptr, len);
1980
1981 while (tptr < pptr + len) {
1982 ND_TCHECK_1(tptr);
1983 ND_PRINT("%s", tok2str(bgp_as_path_segment_open_values,
1984 "?", GET_U_1(tptr)));
1985 ND_TCHECK_1(tptr + 1);
1986 for (i = 0; i < GET_U_1(tptr + 1) * as_size; i += as_size) {
1987 ND_TCHECK_LEN(tptr + 2 + i, as_size);
1988 ND_PRINT("%s ",
1989 as_printf(ndo, astostr, sizeof(astostr),
1990 as_size == 2 ?
1991 GET_BE_U_2(tptr + i + 2) :
1992 GET_BE_U_4(tptr + i + 2)));
1993 }
1994 ND_TCHECK_1(tptr);
1995 ND_PRINT("%s", tok2str(bgp_as_path_segment_close_values,
1996 "?", GET_U_1(tptr)));
1997 ND_TCHECK_1(tptr + 1);
1998 tptr += 2 + GET_U_1(tptr + 1) * as_size;
1999 }
2000 break;
2001 case BGPTYPE_NEXT_HOP:
2002 if (len != 4)
2003 ND_PRINT("invalid len");
2004 else {
2005 ND_TCHECK_4(tptr);
2006 ND_PRINT("%s", GET_IPADDR_STRING(tptr));
2007 }
2008 break;
2009 case BGPTYPE_MULTI_EXIT_DISC:
2010 case BGPTYPE_LOCAL_PREF:
2011 if (len != 4)
2012 ND_PRINT("invalid len");
2013 else {
2014 ND_TCHECK_4(tptr);
2015 ND_PRINT("%u", GET_BE_U_4(tptr));
2016 }
2017 break;
2018 case BGPTYPE_ATOMIC_AGGREGATE:
2019 if (len != 0)
2020 ND_PRINT("invalid len");
2021 break;
2022 case BGPTYPE_AGGREGATOR:
2023
2024 /*
2025 * Depending on the AS encoded is of 2 bytes or of 4 bytes,
2026 * the length of this PA can be either 6 bytes or 8 bytes.
2027 */
2028 if (len != 6 && len != 8) {
2029 ND_PRINT("invalid len");
2030 break;
2031 }
2032 ND_TCHECK_LEN(tptr, len);
2033 if (len == 6) {
2034 ND_PRINT(" AS #%s, origin %s",
2035 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(tptr)),
2036 GET_IPADDR_STRING(tptr + 2));
2037 } else {
2038 ND_PRINT(" AS #%s, origin %s",
2039 as_printf(ndo, astostr, sizeof(astostr),
2040 GET_BE_U_4(tptr)), GET_IPADDR_STRING(tptr + 4));
2041 }
2042 break;
2043 case BGPTYPE_AGGREGATOR4:
2044 if (len != 8) {
2045 ND_PRINT("invalid len");
2046 break;
2047 }
2048 ND_TCHECK_8(tptr);
2049 ND_PRINT(" AS #%s, origin %s",
2050 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)),
2051 GET_IPADDR_STRING(tptr + 4));
2052 break;
2053 case BGPTYPE_COMMUNITIES:
2054 if (len % 4) {
2055 ND_PRINT("invalid len");
2056 break;
2057 }
2058 while (tlen != 0) {
2059 uint32_t comm;
2060 ND_TCHECK_4(tptr);
2061 if (tlen < 4)
2062 goto trunc;
2063 comm = GET_BE_U_4(tptr);
2064 switch (comm) {
2065 case BGP_COMMUNITY_NO_EXPORT:
2066 ND_PRINT(" NO_EXPORT");
2067 break;
2068 case BGP_COMMUNITY_NO_ADVERT:
2069 ND_PRINT(" NO_ADVERTISE");
2070 break;
2071 case BGP_COMMUNITY_NO_EXPORT_SUBCONFED:
2072 ND_PRINT(" NO_EXPORT_SUBCONFED");
2073 break;
2074 default:
2075 ND_PRINT("%u:%u%s",
2076 (comm >> 16) & 0xffff,
2077 comm & 0xffff,
2078 (tlen>4) ? ", " : "");
2079 break;
2080 }
2081 tlen -=4;
2082 tptr +=4;
2083 }
2084 break;
2085 case BGPTYPE_ORIGINATOR_ID:
2086 if (len != 4) {
2087 ND_PRINT("invalid len");
2088 break;
2089 }
2090 ND_TCHECK_4(tptr);
2091 ND_PRINT("%s",GET_IPADDR_STRING(tptr));
2092 break;
2093 case BGPTYPE_CLUSTER_LIST:
2094 if (len % 4) {
2095 ND_PRINT("invalid len");
2096 break;
2097 }
2098 while (tlen != 0) {
2099 ND_TCHECK_4(tptr);
2100 if (tlen < 4)
2101 goto trunc;
2102 ND_PRINT("%s%s",
2103 GET_IPADDR_STRING(tptr),
2104 (tlen>4) ? ", " : "");
2105 tlen -=4;
2106 tptr +=4;
2107 }
2108 break;
2109 case BGPTYPE_MP_REACH_NLRI:
2110 ND_TCHECK_3(tptr);
2111 if (tlen < 3)
2112 goto trunc;
2113 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2114 if (ret == -2)
2115 goto trunc;
2116 if (ret < 0)
2117 break;
2118
2119 tptr += 3;
2120 tlen -= 3;
2121
2122 ND_TCHECK_1(tptr);
2123 if (tlen < 1)
2124 goto trunc;
2125 nhlen = GET_U_1(tptr);
2126 tptr++;
2127 tlen--;
2128
2129 if (nhlen) {
2130 u_int nnh = 0;
2131 uint8_t tnhlen = nhlen;
2132 if (tlen < tnhlen)
2133 goto trunc;
2134 ND_PRINT("\n\t nexthop: ");
2135 while (tnhlen != 0) {
2136 if (nnh++ > 0) {
2137 ND_PRINT(", " );
2138 }
2139 switch(af<<8 | safi) {
2140 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
2141 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
2142 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
2143 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
2144 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
2145 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
2146 case (AFNUM_INET<<8 | SAFNUM_MDT):
2147 if (tnhlen < sizeof(nd_ipv4)) {
2148 ND_PRINT("invalid len");
2149 tptr += tnhlen;
2150 tlen -= tnhlen;
2151 tnhlen = 0;
2152 } else {
2153 ND_TCHECK_LEN(tptr, sizeof(nd_ipv4));
2154 ND_PRINT("%s",GET_IPADDR_STRING(tptr));
2155 tptr += sizeof(nd_ipv4);
2156 tnhlen -= sizeof(nd_ipv4);
2157 tlen -= sizeof(nd_ipv4);
2158 }
2159 break;
2160 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
2161 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
2162 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
2163 if (tnhlen < sizeof(nd_ipv4)+BGP_VPN_RD_LEN) {
2164 ND_PRINT("invalid len");
2165 tptr += tnhlen;
2166 tlen -= tnhlen;
2167 tnhlen = 0;
2168 } else {
2169 ND_TCHECK_LEN(tptr,
2170 sizeof(nd_ipv4) + BGP_VPN_RD_LEN);
2171 ND_PRINT("RD: %s, %s",
2172 bgp_vpn_rd_print(ndo, tptr),
2173 GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN));
2174 tptr += (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2175 tlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2176 tnhlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2177 }
2178 break;
2179 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
2180 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
2181 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
2182 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
2183 if (tnhlen < sizeof(nd_ipv6)) {
2184 ND_PRINT("invalid len");
2185 tptr += tnhlen;
2186 tlen -= tnhlen;
2187 tnhlen = 0;
2188 } else {
2189 ND_TCHECK_LEN(tptr, sizeof(nd_ipv6));
2190 ND_PRINT("%s", GET_IP6ADDR_STRING(tptr));
2191 tptr += sizeof(nd_ipv6);
2192 tlen -= sizeof(nd_ipv6);
2193 tnhlen -= sizeof(nd_ipv6);
2194 }
2195 break;
2196 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
2197 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
2198 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
2199 if (tnhlen < sizeof(nd_ipv6)+BGP_VPN_RD_LEN) {
2200 ND_PRINT("invalid len");
2201 tptr += tnhlen;
2202 tlen -= tnhlen;
2203 tnhlen = 0;
2204 } else {
2205 ND_TCHECK_LEN(tptr,
2206 sizeof(nd_ipv6) + BGP_VPN_RD_LEN);
2207 ND_PRINT("RD: %s, %s",
2208 bgp_vpn_rd_print(ndo, tptr),
2209 GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN));
2210 tptr += (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2211 tlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2212 tnhlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2213 }
2214 break;
2215 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
2216 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
2217 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
2218 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
2219 if (tnhlen < sizeof(nd_ipv4)) {
2220 ND_PRINT("invalid len");
2221 tptr += tnhlen;
2222 tlen -= tnhlen;
2223 tnhlen = 0;
2224 } else {
2225 ND_TCHECK_LEN(tptr, sizeof(nd_ipv4));
2226 ND_PRINT("%s", GET_IPADDR_STRING(tptr));
2227 tptr += (sizeof(nd_ipv4));
2228 tlen -= (sizeof(nd_ipv4));
2229 tnhlen -= (sizeof(nd_ipv4));
2230 }
2231 break;
2232 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
2233 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
2234 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
2235 ND_TCHECK_LEN(tptr, tnhlen);
2236 ND_PRINT("%s", GET_ISONSAP_STRING(tptr, tnhlen));
2237 tptr += tnhlen;
2238 tlen -= tnhlen;
2239 tnhlen = 0;
2240 break;
2241
2242 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
2243 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
2244 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
2245 if (tnhlen < BGP_VPN_RD_LEN+1) {
2246 ND_PRINT("invalid len");
2247 tptr += tnhlen;
2248 tlen -= tnhlen;
2249 tnhlen = 0;
2250 } else {
2251 ND_TCHECK_LEN(tptr, tnhlen);
2252 ND_PRINT("RD: %s, %s",
2253 bgp_vpn_rd_print(ndo, tptr),
2254 GET_ISONSAP_STRING(tptr+BGP_VPN_RD_LEN,tnhlen-BGP_VPN_RD_LEN));
2255 /* rfc986 mapped IPv4 address ? */
2256 if (GET_BE_U_4(tptr + BGP_VPN_RD_LEN) == 0x47000601)
2257 ND_PRINT(" = %s", GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN+4));
2258 /* rfc1888 mapped IPv6 address ? */
2259 else if (GET_BE_U_3(tptr + BGP_VPN_RD_LEN) == 0x350000)
2260 ND_PRINT(" = %s", GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN+3));
2261 tptr += tnhlen;
2262 tlen -= tnhlen;
2263 tnhlen = 0;
2264 }
2265 break;
2266 default:
2267 /*
2268 * bgp_mp_af_print() should have saved us from
2269 * an unsupported AFI/SAFI.
2270 */
2271 ND_PRINT("ERROR: no AFI %u/SAFI %u nexthop decoder", af, safi);
2272 tptr += tnhlen;
2273 tlen -= tnhlen;
2274 tnhlen = 0;
2275 goto done;
2276 break;
2277 }
2278 }
2279 }
2280 ND_PRINT(", nh-length: %u", nhlen);
2281
2282 /* As per RFC 2858; this is reserved in RFC 4760 */
2283 if (tlen < 1)
2284 goto trunc;
2285 ND_TCHECK_1(tptr);
2286 snpa = GET_U_1(tptr);
2287 tptr++;
2288 tlen--;
2289
2290 if (snpa) {
2291 ND_PRINT("\n\t %u SNPA", snpa);
2292 for (/*nothing*/; snpa != 0; snpa--) {
2293 uint8_t snpalen;
2294 if (tlen < 1)
2295 goto trunc;
2296 ND_TCHECK_1(tptr);
2297 snpalen = GET_U_1(tptr);
2298 ND_PRINT("\n\t %u bytes", snpalen);
2299 tptr++;
2300 tlen--;
2301 if (tlen < snpalen)
2302 goto trunc;
2303 ND_TCHECK_LEN(tptr, snpalen);
2304 tptr += snpalen;
2305 tlen -= snpalen;
2306 }
2307 } else {
2308 ND_PRINT(", no SNPA");
2309 }
2310
2311 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2312 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2313
2314 while (tptr < pptr + len) {
2315 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2316 add_path4, add_path6);
2317 if (advance == -2)
2318 goto trunc;
2319 if (advance < 0)
2320 break;
2321 tptr += advance;
2322 }
2323 break;
2324
2325 case BGPTYPE_MP_UNREACH_NLRI:
2326 ND_TCHECK_LEN(tptr, BGP_MP_NLRI_MINSIZE);
2327 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2328 if (ret == -2)
2329 goto trunc;
2330 if (ret < 0)
2331 break;
2332
2333 if (len == BGP_MP_NLRI_MINSIZE)
2334 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2335
2336 tptr += 3;
2337
2338 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2339 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2340
2341 while (tptr < pptr + len) {
2342 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2343 add_path4, add_path6);
2344 if (advance == -2)
2345 goto trunc;
2346 if (advance < 0)
2347 break;
2348 tptr += advance;
2349 }
2350 break;
2351 case BGPTYPE_EXTD_COMMUNITIES:
2352 if (len % 8) {
2353 ND_PRINT("invalid len");
2354 break;
2355 }
2356 while (tlen != 0) {
2357 uint16_t extd_comm;
2358
2359 ND_TCHECK_2(tptr);
2360 if (tlen < 2)
2361 goto trunc;
2362 extd_comm=GET_BE_U_2(tptr);
2363
2364 ND_PRINT("\n\t %s (0x%04x), Flags [%s]",
2365 tok2str(bgp_extd_comm_subtype_values,
2366 "unknown extd community typecode",
2367 extd_comm),
2368 extd_comm,
2369 bittok2str(bgp_extd_comm_flag_values, "none", extd_comm));
2370
2371 ND_TCHECK_8(tptr);
2372 if (tlen < 8)
2373 goto trunc;
2374 ND_PRINT(": ");
2375 bgp_extended_community_print(ndo, tptr);
2376 tlen -= 8;
2377 tptr += 8;
2378 }
2379 break;
2380
2381 case BGPTYPE_PMSI_TUNNEL:
2382 {
2383 uint8_t tunnel_type, flags;
2384
2385 ND_TCHECK_5(tptr);
2386 if (tlen < 5)
2387 goto trunc;
2388 flags = GET_U_1(tptr);
2389 tunnel_type = GET_U_1(tptr + 1);
2390
2391 ND_PRINT("\n\t Tunnel-type %s (%u), Flags [%s], MPLS Label %u",
2392 tok2str(bgp_pmsi_tunnel_values, "Unknown", tunnel_type),
2393 tunnel_type,
2394 bittok2str(bgp_pmsi_flag_values, "none", flags),
2395 GET_BE_U_3(tptr + 2)>>4);
2396
2397 tptr +=5;
2398 tlen -= 5;
2399
2400 switch (tunnel_type) {
2401 case BGP_PMSI_TUNNEL_PIM_SM: /* fall through */
2402 case BGP_PMSI_TUNNEL_PIM_BIDIR:
2403 ND_TCHECK_8(tptr);
2404 ND_PRINT("\n\t Sender %s, P-Group %s",
2405 GET_IPADDR_STRING(tptr),
2406 GET_IPADDR_STRING(tptr+4));
2407 break;
2408
2409 case BGP_PMSI_TUNNEL_PIM_SSM:
2410 ND_TCHECK_8(tptr);
2411 ND_PRINT("\n\t Root-Node %s, P-Group %s",
2412 GET_IPADDR_STRING(tptr),
2413 GET_IPADDR_STRING(tptr+4));
2414 break;
2415 case BGP_PMSI_TUNNEL_INGRESS:
2416 ND_TCHECK_4(tptr);
2417 ND_PRINT("\n\t Tunnel-Endpoint %s",
2418 GET_IPADDR_STRING(tptr));
2419 break;
2420 case BGP_PMSI_TUNNEL_LDP_P2MP: /* fall through */
2421 case BGP_PMSI_TUNNEL_LDP_MP2MP:
2422 ND_TCHECK_8(tptr);
2423 ND_PRINT("\n\t Root-Node %s, LSP-ID 0x%08x",
2424 GET_IPADDR_STRING(tptr),
2425 GET_BE_U_4(tptr + 4));
2426 break;
2427 case BGP_PMSI_TUNNEL_RSVP_P2MP:
2428 ND_TCHECK_8(tptr);
2429 ND_PRINT("\n\t Extended-Tunnel-ID %s, P2MP-ID 0x%08x",
2430 GET_IPADDR_STRING(tptr),
2431 GET_BE_U_4(tptr + 4));
2432 break;
2433 default:
2434 if (ndo->ndo_vflag <= 1) {
2435 print_unknown_data(ndo, tptr, "\n\t ", tlen);
2436 }
2437 }
2438 break;
2439 }
2440 case BGPTYPE_AIGP:
2441 {
2442 uint8_t type;
2443 uint16_t length;
2444
2445 while (tlen >= 3) {
2446
2447 ND_TCHECK_3(tptr);
2448
2449 type = GET_U_1(tptr);
2450 length = GET_BE_U_2(tptr + 1);
2451 tptr += 3;
2452 tlen -= 3;
2453
2454 ND_PRINT("\n\t %s TLV (%u), length %u",
2455 tok2str(bgp_aigp_values, "Unknown", type),
2456 type, length);
2457
2458 if (length < 3)
2459 goto trunc;
2460 length -= 3;
2461
2462 /*
2463 * Check if we can read the TLV data.
2464 */
2465 ND_TCHECK_LEN(tptr + 3, length);
2466 if (tlen < length)
2467 goto trunc;
2468
2469 switch (type) {
2470
2471 case BGP_AIGP_TLV:
2472 if (length < 8)
2473 goto trunc;
2474 ND_PRINT(", metric %" PRIu64,
2475 GET_BE_U_8(tptr));
2476 break;
2477
2478 default:
2479 if (ndo->ndo_vflag <= 1) {
2480 print_unknown_data(ndo, tptr,"\n\t ", length);
2481 }
2482 }
2483
2484 tptr += length;
2485 tlen -= length;
2486 }
2487 break;
2488 }
2489 case BGPTYPE_ATTR_SET:
2490 ND_TCHECK_4(tptr);
2491 if (len < 4)
2492 goto trunc;
2493 ND_PRINT("\n\t Origin AS: %s",
2494 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)));
2495 tptr += 4;
2496 len -= 4;
2497
2498 while (len) {
2499 u_int aflags, alenlen, alen;
2500
2501 ND_TCHECK_2(tptr);
2502 if (len < 2) {
2503 ND_PRINT(" [path attr too short]");
2504 tptr += len;
2505 break;
2506 }
2507 aflags = GET_U_1(tptr);
2508 atype = GET_U_1(tptr + 1);
2509 tptr += 2;
2510 len -= 2;
2511 alenlen = bgp_attr_lenlen(aflags, tptr);
2512 ND_TCHECK_LEN(tptr, alenlen);
2513 if (len < alenlen) {
2514 ND_PRINT(" [path attr too short]");
2515 tptr += len;
2516 break;
2517 }
2518 alen = bgp_attr_len(aflags, tptr);
2519 tptr += alenlen;
2520 len -= alenlen;
2521
2522 ND_PRINT("\n\t %s (%u), length: %u",
2523 tok2str(bgp_attr_values,
2524 "Unknown Attribute", atype),
2525 atype,
2526 alen);
2527
2528 if (aflags) {
2529 ND_PRINT(", Flags [%s%s%s%s",
2530 aflags & 0x80 ? "O" : "",
2531 aflags & 0x40 ? "T" : "",
2532 aflags & 0x20 ? "P" : "",
2533 aflags & 0x10 ? "E" : "");
2534 if (aflags & 0xf)
2535 ND_PRINT("+%x", aflags & 0xf);
2536 ND_PRINT("]");
2537 }
2538 ND_PRINT(": ");
2539 if (len < alen) {
2540 ND_PRINT(" [path attr too short]");
2541 tptr += len;
2542 break;
2543 }
2544 /*
2545 * The protocol encoding per se allows ATTR_SET to be nested
2546 * as many times as the message can accommodate. This printer
2547 * used to be able to recurse into ATTR_SET contents until the
2548 * stack exhaustion, but now there is a limit on that (if live
2549 * protocol exchange goes that many levels deep, something is
2550 * probably wrong anyway). Feel free to refine this value if
2551 * you can find the spec with respective normative text.
2552 */
2553 if (attr_set_level == 10)
2554 ND_PRINT("(too many nested levels, not recursing)");
2555 else if (!bgp_attr_print(ndo, atype, tptr, alen, attr_set_level + 1))
2556 return 0;
2557 tptr += alen;
2558 len -= alen;
2559 }
2560 break;
2561
2562 case BGPTYPE_LARGE_COMMUNITY:
2563 if (len == 0 || len % 12) {
2564 ND_PRINT("invalid len");
2565 break;
2566 }
2567 ND_PRINT("\n\t ");
2568 while (len != 0) {
2569 ND_TCHECK_LEN(tptr, 12);
2570 ND_PRINT("%u:%u:%u%s",
2571 GET_BE_U_4(tptr),
2572 GET_BE_U_4(tptr + 4),
2573 GET_BE_U_4(tptr + 8),
2574 (len > 12) ? ", " : "");
2575 tptr += 12;
2576 /*
2577 * len will always be a multiple of 12, as per the above,
2578 * so this will never underflow.
2579 */
2580 len -= 12;
2581 }
2582 break;
2583 default:
2584 ND_TCHECK_LEN(pptr, len);
2585 ND_PRINT("\n\t no Attribute %u decoder", atype); /* we have no decoder for the attribute */
2586 if (ndo->ndo_vflag <= 1)
2587 print_unknown_data(ndo, pptr, "\n\t ", len);
2588 break;
2589 }
2590 done:
2591 if (ndo->ndo_vflag > 1 && len) { /* omit zero length attributes*/
2592 ND_TCHECK_LEN(pptr, len);
2593 print_unknown_data(ndo, pptr, "\n\t ", len);
2594 }
2595 return 1;
2596
2597 trunc:
2598 return 0;
2599 }
2600
2601 static void
2602 bgp_capabilities_print(netdissect_options *ndo,
2603 const u_char *opt, u_int caps_len)
2604 {
2605 u_int cap_type, cap_len, tcap_len, cap_offset;
2606 u_int i = 0;
2607
2608 while (i < caps_len) {
2609 ND_TCHECK_LEN(opt + i, BGP_CAP_HEADER_SIZE);
2610 cap_type=GET_U_1(opt + i);
2611 cap_len=GET_U_1(opt + i + 1);
2612 ND_PRINT("\n\t %s (%u), length: %u",
2613 tok2str(bgp_capcode_values, "Unknown", cap_type),
2614 cap_type,
2615 cap_len);
2616 ND_TCHECK_LEN(opt + 2 + i, cap_len);
2617 switch (cap_type) {
2618 case BGP_CAPCODE_MP:
2619 /* AFI (16 bits), Reserved (8 bits), SAFI (8 bits) */
2620 if (cap_len < 4) {
2621 ND_PRINT(" (too short, < 4)");
2622 return;
2623 }
2624 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u)",
2625 tok2str(af_values, "Unknown", GET_BE_U_2(opt + i + 2)),
2626 GET_BE_U_2(opt + i + 2),
2627 tok2str(bgp_safi_values, "Unknown", GET_U_1(opt + i + 5)),
2628 GET_U_1(opt + i + 5));
2629 break;
2630 case BGP_CAPCODE_ML:
2631 cap_offset = 2;
2632 tcap_len = cap_len;
2633 while (tcap_len >= 4) {
2634 ND_PRINT( "\n\t\tAFI %s (%u), SAFI %s (%u), Count: %u",
2635 tok2str(af_values, "Unknown",
2636 GET_BE_U_2(opt + i + cap_offset)),
2637 GET_BE_U_2(opt + i + cap_offset),
2638 tok2str(bgp_safi_values, "Unknown",
2639 GET_U_1(opt + i + cap_offset + 2)),
2640 GET_U_1(opt + i + cap_offset + 2),
2641 GET_U_1(opt + i + cap_offset + 3));
2642 tcap_len -= 4;
2643 cap_offset += 4;
2644 }
2645 break;
2646 case BGP_CAPCODE_RESTART:
2647 /* Restart Flags (4 bits), Restart Time in seconds (12 bits) */
2648 if (cap_len < 2) {
2649 ND_PRINT(" (too short, < 2)");
2650 return;
2651 }
2652 tcap_len=cap_len;
2653 ND_PRINT("\n\t\tRestart Flags: [%s], Restart Time %us",
2654 ((GET_U_1(opt + i + 2))&0x80) ? "R" : "none",
2655 GET_BE_U_2(opt + i + 2)&0xfff);
2656 tcap_len-=2;
2657 cap_offset=4;
2658 while(tcap_len>=4) {
2659 ND_PRINT("\n\t\t AFI %s (%u), SAFI %s (%u), Forwarding state preserved: %s",
2660 tok2str(af_values,"Unknown",
2661 GET_BE_U_2(opt + i + cap_offset)),
2662 GET_BE_U_2(opt + i + cap_offset),
2663 tok2str(bgp_safi_values,"Unknown",
2664 GET_U_1(opt + i + cap_offset + 2)),
2665 GET_U_1(opt + (i + cap_offset + 2)),
2666 ((GET_U_1(opt + (i + cap_offset + 3)))&0x80) ? "yes" : "no" );
2667 tcap_len -= 4;
2668 cap_offset += 4;
2669 }
2670 break;
2671 case BGP_CAPCODE_RR:
2672 case BGP_CAPCODE_LLGR:
2673 case BGP_CAPCODE_RR_CISCO:
2674 break;
2675 case BGP_CAPCODE_AS_NEW:
2676 /*
2677 * Extract the 4 byte AS number encoded.
2678 */
2679 if (cap_len < 4) {
2680 ND_PRINT(" (too short, < 4)");
2681 return;
2682 }
2683 ND_PRINT("\n\t\t 4 Byte AS %s",
2684 as_printf(ndo, astostr, sizeof(astostr),
2685 GET_BE_U_4(opt + i + 2)));
2686 break;
2687 case BGP_CAPCODE_ADD_PATH:
2688 if (cap_len == 0) {
2689 ND_PRINT(" (bogus)"); /* length */
2690 break;
2691 }
2692 tcap_len=cap_len;
2693 cap_offset=2;
2694 while (tcap_len != 0) {
2695 if (tcap_len < 4) {
2696 nd_print_invalid(ndo);
2697 break;
2698 }
2699 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u), Send/Receive: %s",
2700 tok2str(af_values,"Unknown",GET_BE_U_2(opt + i + cap_offset)),
2701 GET_BE_U_2(opt + i + cap_offset),
2702 tok2str(bgp_safi_values,"Unknown",GET_U_1(opt + i + cap_offset + 2)),
2703 GET_U_1(opt + (i + cap_offset + 2)),
2704 tok2str(bgp_add_path_recvsend,"Bogus (0x%02x)",GET_U_1(opt + i + cap_offset + 3))
2705 );
2706 tcap_len -= 4;
2707 cap_offset += 4;
2708 }
2709 break;
2710 default:
2711 ND_PRINT("\n\t\tno decoder for Capability %u",
2712 cap_type);
2713 if (ndo->ndo_vflag <= 1)
2714 print_unknown_data(ndo, opt + i + 2, "\n\t\t",
2715 cap_len);
2716 break;
2717 }
2718 if (ndo->ndo_vflag > 1 && cap_len != 0) {
2719 print_unknown_data(ndo, opt + i + 2, "\n\t\t", cap_len);
2720 }
2721 i += BGP_CAP_HEADER_SIZE + cap_len;
2722 }
2723 return;
2724
2725 trunc:
2726 nd_print_trunc(ndo);
2727 }
2728
2729 static void
2730 bgp_open_print(netdissect_options *ndo,
2731 const u_char *dat, u_int length)
2732 {
2733 const struct bgp_open *bgp_open_header;
2734 u_int optslen;
2735 const struct bgp_opt *bgpopt;
2736 const u_char *opt;
2737 u_int i;
2738
2739 ND_TCHECK_LEN(dat, BGP_OPEN_SIZE);
2740 if (length < BGP_OPEN_SIZE)
2741 goto trunc;
2742
2743 bgp_open_header = (const struct bgp_open *)dat;
2744
2745 ND_PRINT("\n\t Version %u, ",
2746 GET_U_1(bgp_open_header->bgpo_version));
2747 ND_PRINT("my AS %s, ",
2748 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(bgp_open_header->bgpo_myas)));
2749 ND_PRINT("Holdtime %us, ",
2750 GET_BE_U_2(bgp_open_header->bgpo_holdtime));
2751 ND_PRINT("ID %s", GET_IPADDR_STRING(bgp_open_header->bgpo_id));
2752 optslen = GET_U_1(bgp_open_header->bgpo_optlen);
2753 ND_PRINT("\n\t Optional parameters, length: %u", optslen);
2754
2755 opt = dat + BGP_OPEN_SIZE;
2756 length -= BGP_OPEN_SIZE;
2757
2758 i = 0;
2759 while (i < optslen) {
2760 uint8_t opt_type, opt_len;
2761
2762 ND_TCHECK_LEN(opt + i, BGP_OPT_SIZE);
2763 if (length < BGP_OPT_SIZE + i)
2764 goto trunc;
2765 bgpopt = (const struct bgp_opt *)(opt + i);
2766 opt_type = GET_U_1(bgpopt->bgpopt_type);
2767 opt_len = GET_U_1(bgpopt->bgpopt_len);
2768 if (BGP_OPT_SIZE + i + opt_len > optslen) {
2769 ND_PRINT("\n\t Option %u, length: %u, goes past the end of the options",
2770 opt_type, opt_len);
2771 break;
2772 }
2773
2774 ND_PRINT("\n\t Option %s (%u), length: %u",
2775 tok2str(bgp_opt_values,"Unknown",opt_type),
2776 opt_type,
2777 opt_len);
2778
2779 /* now let's decode the options we know*/
2780 switch(opt_type) {
2781
2782 case BGP_OPT_CAP:
2783 bgp_capabilities_print(ndo, opt + BGP_OPT_SIZE + i,
2784 opt_len);
2785 break;
2786
2787 case BGP_OPT_AUTH:
2788 default:
2789 ND_PRINT("\n\t no decoder for option %u",
2790 opt_type);
2791 break;
2792 }
2793 i += BGP_OPT_SIZE + opt_len;
2794 }
2795 return;
2796 trunc:
2797 nd_print_trunc(ndo);
2798 }
2799
2800 static void
2801 bgp_update_print(netdissect_options *ndo,
2802 const u_char *dat, u_int length)
2803 {
2804 const u_char *p;
2805 u_int withdrawn_routes_len;
2806 char buf[MAXHOSTNAMELEN + 100];
2807 int wpfx;
2808 u_int len;
2809 int i;
2810 int add_path;
2811 u_int path_id = 0;
2812
2813 ND_TCHECK_LEN(dat, BGP_SIZE);
2814 if (length < BGP_SIZE)
2815 goto trunc;
2816 p = dat + BGP_SIZE;
2817 length -= BGP_SIZE;
2818
2819 /* Unfeasible routes */
2820 ND_TCHECK_2(p);
2821 if (length < 2)
2822 goto trunc;
2823 withdrawn_routes_len = GET_BE_U_2(p);
2824 p += 2;
2825 length -= 2;
2826 if (withdrawn_routes_len > 1) {
2827 /*
2828 * Without keeping state from the original NLRI message,
2829 * it's not possible to tell if this a v4 or v6 route,
2830 * so only try to decode it if we're not v6 enabled.
2831 */
2832 ND_TCHECK_LEN(p, withdrawn_routes_len);
2833 if (length < withdrawn_routes_len)
2834 goto trunc;
2835 ND_PRINT("\n\t Withdrawn routes:");
2836 add_path = check_add_path(ndo, p, withdrawn_routes_len, 32);
2837 while (withdrawn_routes_len != 0) {
2838 if (add_path) {
2839 if (withdrawn_routes_len < 4) {
2840 p += withdrawn_routes_len;
2841 length -= withdrawn_routes_len;
2842 break;
2843 }
2844 path_id = GET_BE_U_4(p);
2845 p += 4;
2846 length -= 4;
2847 withdrawn_routes_len -= 4;
2848 }
2849 wpfx = decode_prefix4(ndo, p, withdrawn_routes_len, buf, sizeof(buf));
2850 if (wpfx == -1) {
2851 ND_PRINT("\n\t (illegal prefix length)");
2852 break;
2853 } else if (wpfx == -2)
2854 goto trunc;
2855 else if (wpfx == -3)
2856 goto trunc; /* bytes left, but not enough */
2857 else {
2858 ND_PRINT("\n\t %s", buf);
2859 if (add_path) {
2860 ND_PRINT(" Path Id: %u", path_id);
2861 }
2862 p += wpfx;
2863 length -= wpfx;
2864 withdrawn_routes_len -= wpfx;
2865 }
2866 }
2867 } else {
2868 ND_TCHECK_LEN(p, withdrawn_routes_len);
2869 if (length < withdrawn_routes_len)
2870 goto trunc;
2871 p += withdrawn_routes_len;
2872 length -= withdrawn_routes_len;
2873 }
2874
2875 ND_TCHECK_2(p);
2876 if (length < 2)
2877 goto trunc;
2878 len = GET_BE_U_2(p);
2879 p += 2;
2880 length -= 2;
2881
2882 if (withdrawn_routes_len == 0 && len == 0 && length == 0) {
2883 /* No withdrawn routes, no path attributes, no NLRI */
2884 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2885 return;
2886 }
2887
2888 if (len) {
2889 /* do something more useful!*/
2890 while (len) {
2891 uint8_t aflags, atype, alenlen;
2892 uint16_t alen;
2893
2894 ND_TCHECK_2(p);
2895 if (length < 2)
2896 goto trunc;
2897 if (len < 2) {
2898 ND_PRINT("\n\t [path attrs too short]");
2899 p += len;
2900 length -= len;
2901 break;
2902 }
2903 aflags = GET_U_1(p);
2904 atype = GET_U_1(p + 1);
2905 p += 2;
2906 len -= 2;
2907 length -= 2;
2908 alenlen = bgp_attr_lenlen(aflags, p);
2909 ND_TCHECK_LEN(p, alenlen);
2910 if (length < alenlen)
2911 goto trunc;
2912 if (len < alenlen) {
2913 ND_PRINT("\n\t [path attrs too short]");
2914 p += len;
2915 length -= len;
2916 break;
2917 }
2918 alen = bgp_attr_len(aflags, p);
2919 p += alenlen;
2920 len -= alenlen;
2921 length -= alenlen;
2922
2923 ND_PRINT("\n\t %s (%u), length: %u",
2924 tok2str(bgp_attr_values, "Unknown Attribute", atype),
2925 atype,
2926 alen);
2927
2928 if (aflags) {
2929 ND_PRINT(", Flags [%s%s%s%s",
2930 aflags & 0x80 ? "O" : "",
2931 aflags & 0x40 ? "T" : "",
2932 aflags & 0x20 ? "P" : "",
2933 aflags & 0x10 ? "E" : "");
2934 if (aflags & 0xf)
2935 ND_PRINT("+%x", aflags & 0xf);
2936 ND_PRINT("]: ");
2937 }
2938 if (len < alen) {
2939 ND_PRINT(" [path attrs too short]");
2940 p += len;
2941 length -= len;
2942 break;
2943 }
2944 if (length < alen)
2945 goto trunc;
2946 if (!bgp_attr_print(ndo, atype, p, alen, 0))
2947 goto trunc;
2948 p += alen;
2949 len -= alen;
2950 length -= alen;
2951 }
2952 }
2953
2954 if (length) {
2955 add_path = check_add_path(ndo, p, length, 32);
2956 ND_PRINT("\n\t Updated routes:");
2957 while (length != 0) {
2958 if (add_path) {
2959 ND_TCHECK_4(p);
2960 if (length < 4)
2961 goto trunc;
2962 path_id = GET_BE_U_4(p);
2963 p += 4;
2964 length -= 4;
2965 }
2966 i = decode_prefix4(ndo, p, length, buf, sizeof(buf));
2967 if (i == -1) {
2968 ND_PRINT("\n\t (illegal prefix length)");
2969 break;
2970 } else if (i == -2)
2971 goto trunc;
2972 else if (i == -3)
2973 goto trunc; /* bytes left, but not enough */
2974 else {
2975 ND_PRINT("\n\t %s", buf);
2976 if (add_path) {
2977 ND_PRINT(" Path Id: %u", path_id);
2978 }
2979 p += i;
2980 length -= i;
2981 }
2982 }
2983 }
2984 return;
2985 trunc:
2986 nd_print_trunc(ndo);
2987 }
2988
2989 static void
2990 bgp_notification_print(netdissect_options *ndo,
2991 const u_char *dat, u_int length)
2992 {
2993 const struct bgp_notification *bgp_notification_header;
2994 const u_char *tptr;
2995 uint8_t bgpn_major, bgpn_minor;
2996 uint8_t shutdown_comm_length;
2997 uint8_t remainder_offset;
2998
2999 ND_TCHECK_LEN(dat, BGP_NOTIFICATION_SIZE);
3000 if (length<BGP_NOTIFICATION_SIZE)
3001 return;
3002
3003 bgp_notification_header = (const struct bgp_notification *)dat;
3004 bgpn_major = GET_U_1(bgp_notification_header->bgpn_major);
3005 bgpn_minor = GET_U_1(bgp_notification_header->bgpn_minor);
3006
3007 ND_PRINT(", %s (%u)",
3008 tok2str(bgp_notify_major_values, "Unknown Error",
3009 bgpn_major),
3010 bgpn_major);
3011
3012 switch (bgpn_major) {
3013
3014 case BGP_NOTIFY_MAJOR_MSG:
3015 ND_PRINT(", subcode %s (%u)",
3016 tok2str(bgp_notify_minor_msg_values, "Unknown",
3017 bgpn_minor),
3018 bgpn_minor);
3019 break;
3020 case BGP_NOTIFY_MAJOR_OPEN:
3021 ND_PRINT(", subcode %s (%u)",
3022 tok2str(bgp_notify_minor_open_values, "Unknown",
3023 bgpn_minor),
3024 bgpn_minor);
3025 break;
3026 case BGP_NOTIFY_MAJOR_UPDATE:
3027 ND_PRINT(", subcode %s (%u)",
3028 tok2str(bgp_notify_minor_update_values, "Unknown",
3029 bgpn_minor),
3030 bgpn_minor);
3031 break;
3032 case BGP_NOTIFY_MAJOR_FSM:
3033 ND_PRINT(" subcode %s (%u)",
3034 tok2str(bgp_notify_minor_fsm_values, "Unknown",
3035 bgpn_minor),
3036 bgpn_minor);
3037 break;
3038 case BGP_NOTIFY_MAJOR_CAP:
3039 ND_PRINT(" subcode %s (%u)",
3040 tok2str(bgp_notify_minor_cap_values, "Unknown",
3041 bgpn_minor),
3042 bgpn_minor);
3043 break;
3044 case BGP_NOTIFY_MAJOR_CEASE:
3045 ND_PRINT(", subcode %s (%u)",
3046 tok2str(bgp_notify_minor_cease_values, "Unknown",
3047 bgpn_minor),
3048 bgpn_minor);
3049
3050 /* draft-ietf-idr-cease-subcode-02 mentions optionally 7 bytes
3051 * for the maxprefix subtype, which may contain AFI, SAFI and MAXPREFIXES
3052 */
3053 if(bgpn_minor == BGP_NOTIFY_MINOR_CEASE_MAXPRFX && length >= BGP_NOTIFICATION_SIZE + 7) {
3054 tptr = dat + BGP_NOTIFICATION_SIZE;
3055 ND_TCHECK_7(tptr);
3056 ND_PRINT(", AFI %s (%u), SAFI %s (%u), Max Prefixes: %u",
3057 tok2str(af_values, "Unknown", GET_BE_U_2(tptr)),
3058 GET_BE_U_2(tptr),
3059 tok2str(bgp_safi_values, "Unknown", GET_U_1((tptr + 2))),
3060 GET_U_1((tptr + 2)),
3061 GET_BE_U_4(tptr + 3));
3062 }
3063 /*
3064 * draft-ietf-idr-shutdown describes a method to send a communication
3065 * intended for human consumption regarding the Administrative Shutdown
3066 */
3067 if ((bgpn_minor == BGP_NOTIFY_MINOR_CEASE_SHUT ||
3068 bgpn_minor == BGP_NOTIFY_MINOR_CEASE_RESET) &&
3069 length >= BGP_NOTIFICATION_SIZE + 1) {
3070 tptr = dat + BGP_NOTIFICATION_SIZE;
3071 ND_TCHECK_1(tptr);
3072 shutdown_comm_length = GET_U_1(tptr);
3073 remainder_offset = 0;
3074 /* garbage, hexdump it all */
3075 if (shutdown_comm_length > BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN ||
3076 shutdown_comm_length > length - (BGP_NOTIFICATION_SIZE + 1)) {
3077 ND_PRINT(", invalid Shutdown Communication length");
3078 }
3079 else if (shutdown_comm_length == 0) {
3080 ND_PRINT(", empty Shutdown Communication");
3081 remainder_offset += 1;
3082 }
3083 /* a proper shutdown communication */
3084 else {
3085 ND_TCHECK_LEN(tptr + 1, shutdown_comm_length);
3086 ND_PRINT(", Shutdown Communication (length: %u): \"", shutdown_comm_length);
3087 (void)nd_printn(ndo, tptr+1, shutdown_comm_length, NULL);
3088 ND_PRINT("\"");
3089 remainder_offset += shutdown_comm_length + 1;
3090 }
3091 /* if there is trailing data, hexdump it */
3092 if(length - (remainder_offset + BGP_NOTIFICATION_SIZE) > 0) {
3093 ND_PRINT(", Data: (length: %u)", length - (remainder_offset + BGP_NOTIFICATION_SIZE));
3094 hex_print(ndo, "\n\t\t", tptr + remainder_offset, length - (remainder_offset + BGP_NOTIFICATION_SIZE));
3095 }
3096 }
3097 break;
3098 default:
3099 break;
3100 }
3101
3102 return;
3103 trunc:
3104 nd_print_trunc(ndo);
3105 }
3106
3107 static void
3108 bgp_route_refresh_print(netdissect_options *ndo,
3109 const u_char *pptr, u_int len)
3110 {
3111 const struct bgp_route_refresh *bgp_route_refresh_header;
3112
3113 ND_TCHECK_LEN(pptr, BGP_ROUTE_REFRESH_SIZE);
3114
3115 /* some little sanity checking */
3116 if (len<BGP_ROUTE_REFRESH_SIZE)
3117 return;
3118
3119 bgp_route_refresh_header = (const struct bgp_route_refresh *)pptr;
3120
3121 ND_PRINT("\n\t AFI %s (%u), SAFI %s (%u)",
3122 tok2str(af_values,"Unknown",
3123 GET_BE_U_2(bgp_route_refresh_header->afi)),
3124 GET_BE_U_2(bgp_route_refresh_header->afi),
3125 tok2str(bgp_safi_values,"Unknown",
3126 GET_U_1(bgp_route_refresh_header->safi)),
3127 GET_U_1(bgp_route_refresh_header->safi));
3128
3129 if (ndo->ndo_vflag > 1) {
3130 ND_TCHECK_LEN(pptr, len);
3131 print_unknown_data(ndo, pptr, "\n\t ", len);
3132 }
3133
3134 return;
3135 trunc:
3136 nd_print_trunc(ndo);
3137 }
3138
3139 static int
3140 bgp_pdu_print(netdissect_options *ndo,
3141 const u_char *dat, u_int length)
3142 {
3143 const struct bgp *bgp_header;
3144 uint8_t bgp_type;
3145
3146 ND_TCHECK_LEN(dat, BGP_SIZE);
3147 bgp_header = (const struct bgp *)dat;
3148 bgp_type = GET_U_1(bgp_header->bgp_type);
3149
3150 ND_PRINT("\n\t%s Message (%u), length: %u",
3151 tok2str(bgp_msg_values, "Unknown", bgp_type),
3152 bgp_type,
3153 length);
3154
3155 switch (bgp_type) {
3156 case BGP_OPEN:
3157 bgp_open_print(ndo, dat, length);
3158 break;
3159 case BGP_UPDATE:
3160 bgp_update_print(ndo, dat, length);
3161 break;
3162 case BGP_NOTIFICATION:
3163 bgp_notification_print(ndo, dat, length);
3164 break;
3165 case BGP_KEEPALIVE:
3166 break;
3167 case BGP_ROUTE_REFRESH:
3168 bgp_route_refresh_print(ndo, dat, length);
3169 break;
3170 default:
3171 /* we have no decoder for the BGP message */
3172 ND_TCHECK_LEN(dat, length);
3173 ND_PRINT("\n\t no Message %u decoder", bgp_type);
3174 print_unknown_data(ndo, dat, "\n\t ", length);
3175 break;
3176 }
3177 return 1;
3178 trunc:
3179 nd_print_trunc(ndo);
3180 return 0;
3181 }
3182
3183 void
3184 bgp_print(netdissect_options *ndo,
3185 const u_char *dat, u_int length _U_)
3186 {
3187 const u_char *p;
3188 const u_char *ep = ndo->ndo_snapend;
3189 const u_char *start;
3190 const u_char marker[] = {
3191 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3192 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3193 };
3194 const struct bgp *bgp_header;
3195 uint16_t hlen;
3196
3197 ndo->ndo_protocol = "bgp";
3198 ND_PRINT(": BGP");
3199
3200 if (ndo->ndo_vflag < 1) /* lets be less chatty */
3201 return;
3202
3203 p = dat;
3204 start = p;
3205 while (p < ep) {
3206 if (!ND_TTEST_1(p))
3207 break;
3208 if (GET_U_1(p) != 0xff) {
3209 p++;
3210 continue;
3211 }
3212
3213 if (!ND_TTEST_LEN(p, sizeof(marker)))
3214 break;
3215 if (memcmp(p, marker, sizeof(marker)) != 0) {
3216 p++;
3217 continue;
3218 }
3219
3220 /* found BGP header */
3221 ND_TCHECK_LEN(p, BGP_SIZE);
3222 bgp_header = (const struct bgp *)p;
3223
3224 if (start != p)
3225 nd_print_trunc(ndo);
3226
3227 hlen = GET_BE_U_2(bgp_header->bgp_len);
3228 if (hlen < BGP_SIZE) {
3229 ND_PRINT("\nmessage length %u < %u", hlen, BGP_SIZE);
3230 nd_print_invalid(ndo);
3231 break;
3232 }
3233
3234 if (ND_TTEST_LEN(p, hlen)) {
3235 if (!bgp_pdu_print(ndo, p, hlen))
3236 return;
3237 p += hlen;
3238 start = p;
3239 } else {
3240 ND_PRINT("\n[|BGP %s]",
3241 tok2str(bgp_msg_values,
3242 "Unknown Message Type",
3243 GET_U_1(bgp_header->bgp_type)));
3244 break;
3245 }
3246 }
3247
3248 return;
3249
3250 trunc:
3251 nd_print_trunc(ndo);
3252 }
[mirror] the TCPdump network dissector