]> The Tcpdump Group git mirrors - tcpdump/blob - print-bgp.c
projects / tcpdump / blob
summary | shortlog | log | commit | commitdiff | tree
history | raw | HEAD
Revert "Clean a bunch of fuzzed files not to fuzz the container."
[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 nd_uint8_t bgpo_opttype; /* RFC9072 */
84 nd_uint16_t bgpo_optlen_extended; /* RFC9072 */
85 /* options should follow */
86 };
87 #define BGP_OPEN_SIZE 29 /* unaligned */
88
89 struct bgp_opt {
90 nd_uint8_t bgpopt_type;
91 nd_uint16_t bgpopt_len; /* Can be one or two bytes, depending on RFC9072 */
92 /* variable length */
93 };
94 #define BGP_OPT_SIZE 2 /* some compilers may pad to 4 bytes */
95 #define BGP_CAP_HEADER_SIZE 2 /* some compilers may pad to 4 bytes */
96
97 struct bgp_notification {
98 nd_byte bgpn_marker[16];
99 nd_uint16_t bgpn_len;
100 nd_uint8_t bgpn_type;
101 nd_uint8_t bgpn_major;
102 nd_uint8_t bgpn_minor;
103 };
104 #define BGP_NOTIFICATION_SIZE 21 /* unaligned */
105
106 struct bgp_route_refresh {
107 nd_byte bgp_marker[16];
108 nd_uint16_t len;
109 nd_uint8_t type; /* No padding after this; afi is, in fact, not aligned */
110 nd_uint16_t afi;
111 nd_uint8_t subtype;
112 nd_uint8_t safi;
113 };
114 #define BGP_ROUTE_REFRESH_SIZE 23
115 #define BGP_ROUTE_REFRESH_SUBTYPE_NORMAL 0
116 #define BGP_ROUTE_REFRESH_SUBTYPE_BORR 1
117 #define BGP_ROUTE_REFRESH_SUBTYPE_EORR 2
118 #define BGP_ROUTE_REFRESH_SUBTYPE_RESERVED 255
119
120 static const struct tok bgp_route_refresh_subtype_values[] = {
121 {BGP_ROUTE_REFRESH_SUBTYPE_NORMAL, "Normal route refresh request"},
122 {BGP_ROUTE_REFRESH_SUBTYPE_BORR,
123 "Demarcation of the beginning of a route refresh"},
124 {BGP_ROUTE_REFRESH_SUBTYPE_EORR,
125 "Demarcation of the ending of a route refresh"},
126 {0, NULL}};
127
128 #define bgp_attr_lenlen(flags, p) \
129 (((flags) & 0x10) ? 2U : 1U)
130 #define bgp_attr_len(flags, p) \
131 (((flags) & 0x10) ? GET_BE_U_2(p) : GET_U_1(p))
132
133 #define BGPTYPE_ORIGIN 1
134 #define BGPTYPE_AS_PATH 2
135 #define BGPTYPE_NEXT_HOP 3
136 #define BGPTYPE_MULTI_EXIT_DISC 4
137 #define BGPTYPE_LOCAL_PREF 5
138 #define BGPTYPE_ATOMIC_AGGREGATE 6
139 #define BGPTYPE_AGGREGATOR 7
140 #define BGPTYPE_COMMUNITIES 8 /* RFC1997 */
141 #define BGPTYPE_ORIGINATOR_ID 9 /* RFC4456 */
142 #define BGPTYPE_CLUSTER_LIST 10 /* RFC4456 */
143 #define BGPTYPE_MP_REACH_NLRI 14 /* RFC4760 */
144 #define BGPTYPE_MP_UNREACH_NLRI 15 /* RFC4760 */
145 #define BGPTYPE_EXTD_COMMUNITIES 16 /* RFC4360 */
146 #define BGPTYPE_AS4_PATH 17 /* RFC6793 */
147 #define BGPTYPE_AGGREGATOR4 18 /* RFC6793 */
148 #define BGPTYPE_PMSI_TUNNEL 22 /* RFC6514 */
149 #define BGPTYPE_TUNNEL_ENCAP 23 /* RFC5512 */
150 #define BGPTYPE_TRAFFIC_ENG 24 /* RFC5543 */
151 #define BGPTYPE_IPV6_EXTD_COMMUNITIES 25 /* RFC5701 */
152 #define BGPTYPE_AIGP 26 /* RFC7311 */
153 #define BGPTYPE_PE_DISTINGUISHER_LABEL 27 /* RFC6514 */
154 #define BGPTYPE_ENTROPY_LABEL 28 /* RFC6790 */
155 #define BGPTYPE_LARGE_COMMUNITY 32 /* draft-ietf-idr-large-community-05 */
156 #define BGPTYPE_ATTR_SET 128 /* RFC6368 */
157
158 #define BGP_MP_NLRI_MINSIZE 3 /* End of RIB Marker detection */
159
160 static const struct tok bgp_attr_values[] = {
161 { BGPTYPE_ORIGIN, "Origin"},
162 { BGPTYPE_AS_PATH, "AS Path"},
163 { BGPTYPE_AS4_PATH, "AS4 Path"},
164 { BGPTYPE_NEXT_HOP, "Next Hop"},
165 { BGPTYPE_MULTI_EXIT_DISC, "Multi Exit Discriminator"},
166 { BGPTYPE_LOCAL_PREF, "Local Preference"},
167 { BGPTYPE_ATOMIC_AGGREGATE, "Atomic Aggregate"},
168 { BGPTYPE_AGGREGATOR, "Aggregator"},
169 { BGPTYPE_AGGREGATOR4, "Aggregator4"},
170 { BGPTYPE_COMMUNITIES, "Community"},
171 { BGPTYPE_ORIGINATOR_ID, "Originator ID"},
172 { BGPTYPE_CLUSTER_LIST, "Cluster List"},
173 { BGPTYPE_MP_REACH_NLRI, "Multi-Protocol Reach NLRI"},
174 { BGPTYPE_MP_UNREACH_NLRI, "Multi-Protocol Unreach NLRI"},
175 { BGPTYPE_EXTD_COMMUNITIES, "Extended Community"},
176 { BGPTYPE_PMSI_TUNNEL, "PMSI Tunnel"},
177 { BGPTYPE_TUNNEL_ENCAP, "Tunnel Encapsulation"},
178 { BGPTYPE_TRAFFIC_ENG, "Traffic Engineering"},
179 { BGPTYPE_IPV6_EXTD_COMMUNITIES, "IPv6 Extended Community"},
180 { BGPTYPE_AIGP, "Accumulated IGP Metric"},
181 { BGPTYPE_PE_DISTINGUISHER_LABEL, "PE Distinguisher Label"},
182 { BGPTYPE_ENTROPY_LABEL, "Entropy Label"},
183 { BGPTYPE_LARGE_COMMUNITY, "Large Community"},
184 { BGPTYPE_ATTR_SET, "Attribute Set"},
185 { 255, "Reserved for development"},
186 { 0, NULL}
187 };
188
189 #define BGP_AS_SET 1
190 #define BGP_AS_SEQUENCE 2
191 #define BGP_CONFED_AS_SEQUENCE 3 /* draft-ietf-idr-rfc3065bis-01 */
192 #define BGP_CONFED_AS_SET 4 /* draft-ietf-idr-rfc3065bis-01 */
193
194 #define BGP_AS_SEG_TYPE_MIN BGP_AS_SET
195 #define BGP_AS_SEG_TYPE_MAX BGP_CONFED_AS_SET
196
197 static const struct tok bgp_as_path_segment_open_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 static const struct tok bgp_as_path_segment_close_values[] = {
206 { BGP_AS_SEQUENCE, ""},
207 { BGP_AS_SET, "}"},
208 { BGP_CONFED_AS_SEQUENCE, ")"},
209 { BGP_CONFED_AS_SET, "})"},
210 { 0, NULL}
211 };
212
213 #define BGP_OPT_AUTH 1
214 #define BGP_OPT_CAP 2
215
216 static const struct tok bgp_opt_values[] = {
217 { BGP_OPT_AUTH, "Authentication Information"},
218 { BGP_OPT_CAP, "Capabilities Advertisement"},
219 { 0, NULL}
220 };
221
222 #define BGP_CAPCODE_MP 1 /* RFC2858 */
223 #define BGP_CAPCODE_RR 2 /* RFC2918 */
224 #define BGP_CAPCODE_ORF 3 /* RFC5291 */
225 #define BGP_CAPCODE_MR 4 /* RFC3107 */
226 #define BGP_CAPCODE_EXT_NH 5 /* RFC5549 */
227 #define BGP_CAPCODE_EXT_MSG 6 /* RFC8654 */
228 #define BGP_CAPCODE_ML 8 /* RFC8277 */
229 #define BGP_CAPCODE_RESTART 64 /* RFC4724 */
230 #define BGP_CAPCODE_AS_NEW 65 /* RFC6793 */
231 #define BGP_CAPCODE_DYN_CAP 67 /* draft-ietf-idr-dynamic-cap */
232 #define BGP_CAPCODE_MULTISESS 68 /* draft-ietf-idr-bgp-multisession */
233 #define BGP_CAPCODE_ADD_PATH 69 /* RFC7911 */
234 #define BGP_CAPCODE_ENH_RR 70 /* RFC7313 */
235 #define BGP_CAPCODE_LLGR 71 /* draft-uttaro-idr-bgp-persistence-05 */
236 #define BGP_CAPCODE_RR_CISCO 128
237
238 static const struct tok bgp_capcode_values[] = {
239 { BGP_CAPCODE_MP, "Multiprotocol Extensions"},
240 { BGP_CAPCODE_RR, "Route Refresh"},
241 { BGP_CAPCODE_ORF, "Cooperative Route Filtering"},
242 { BGP_CAPCODE_MR, "Multiple Routes to a Destination"},
243 { BGP_CAPCODE_EXT_NH, "Extended Next Hop Encoding"},
244 { BGP_CAPCODE_EXT_MSG, "BGP Extended Message"},
245 { BGP_CAPCODE_ML, "Multiple Labels"},
246 { BGP_CAPCODE_RESTART, "Graceful Restart"},
247 { BGP_CAPCODE_AS_NEW, "32-Bit AS Number"},
248 { BGP_CAPCODE_DYN_CAP, "Dynamic Capability"},
249 { BGP_CAPCODE_MULTISESS, "Multisession BGP"},
250 { BGP_CAPCODE_ADD_PATH, "Multiple Paths"},
251 { BGP_CAPCODE_ENH_RR, "Enhanced Route Refresh"},
252 { BGP_CAPCODE_LLGR, "Long-lived Graceful Restart"},
253 { BGP_CAPCODE_RR_CISCO, "Route Refresh (Cisco)"},
254 { 0, NULL}
255 };
256
257 #define BGP_NOTIFY_MAJOR_MSG 1
258 #define BGP_NOTIFY_MAJOR_OPEN 2
259 #define BGP_NOTIFY_MAJOR_UPDATE 3
260 #define BGP_NOTIFY_MAJOR_HOLDTIME 4
261 #define BGP_NOTIFY_MAJOR_FSM 5
262 #define BGP_NOTIFY_MAJOR_CEASE 6
263 #define BGP_NOTIFY_MAJOR_CAP 7
264
265 static const struct tok bgp_notify_major_values[] = {
266 { BGP_NOTIFY_MAJOR_MSG, "Message Header Error"},
267 { BGP_NOTIFY_MAJOR_OPEN, "OPEN Message Error"},
268 { BGP_NOTIFY_MAJOR_UPDATE, "UPDATE Message Error"},
269 { BGP_NOTIFY_MAJOR_HOLDTIME,"Hold Timer Expired"},
270 { BGP_NOTIFY_MAJOR_FSM, "Finite State Machine Error"},
271 { BGP_NOTIFY_MAJOR_CEASE, "Cease"},
272 { BGP_NOTIFY_MAJOR_CAP, "Capability Message Error"},
273 { 0, NULL}
274 };
275
276 /* RFC 4486 */
277 #define BGP_NOTIFY_MINOR_CEASE_MAXPRFX 1
278 #define BGP_NOTIFY_MINOR_CEASE_SHUT 2
279 #define BGP_NOTIFY_MINOR_CEASE_RESET 4
280 static const struct tok bgp_notify_minor_cease_values[] = {
281 { BGP_NOTIFY_MINOR_CEASE_MAXPRFX, "Maximum Number of Prefixes Reached"},
282 { BGP_NOTIFY_MINOR_CEASE_SHUT, "Administrative Shutdown"},
283 { 3, "Peer Unconfigured"},
284 { BGP_NOTIFY_MINOR_CEASE_RESET, "Administrative Reset"},
285 { 5, "Connection Rejected"},
286 { 6, "Other Configuration Change"},
287 { 7, "Connection Collision Resolution"},
288 { 0, NULL}
289 };
290
291 static const struct tok bgp_notify_minor_msg_values[] = {
292 { 1, "Connection Not Synchronized"},
293 { 2, "Bad Message Length"},
294 { 3, "Bad Message Type"},
295 { 0, NULL}
296 };
297
298 static const struct tok bgp_notify_minor_open_values[] = {
299 { 1, "Unsupported Version Number"},
300 { 2, "Bad Peer AS"},
301 { 3, "Bad BGP Identifier"},
302 { 4, "Unsupported Optional Parameter"},
303 { 5, "Authentication Failure"},
304 { 6, "Unacceptable Hold Time"},
305 { 7, "Capability Message Error"},
306 { 0, NULL}
307 };
308
309 static const struct tok bgp_notify_minor_update_values[] = {
310 { 1, "Malformed Attribute List"},
311 { 2, "Unrecognized Well-known Attribute"},
312 { 3, "Missing Well-known Attribute"},
313 { 4, "Attribute Flags Error"},
314 { 5, "Attribute Length Error"},
315 { 6, "Invalid ORIGIN Attribute"},
316 { 7, "AS Routing Loop"},
317 { 8, "Invalid NEXT_HOP Attribute"},
318 { 9, "Optional Attribute Error"},
319 { 10, "Invalid Network Field"},
320 { 11, "Malformed AS_PATH"},
321 { 0, NULL}
322 };
323
324 static const struct tok bgp_notify_minor_fsm_values[] = {
325 { 0, "Unspecified Error"},
326 { 1, "In OpenSent State"},
327 { 2, "In OpenConfirm State"},
328 { 3, "In Established State"},
329 { 0, NULL }
330 };
331
332 static const struct tok bgp_notify_minor_cap_values[] = {
333 { 1, "Invalid Action Value" },
334 { 2, "Invalid Capability Length" },
335 { 3, "Malformed Capability Value" },
336 { 4, "Unsupported Capability Code" },
337 { 0, NULL }
338 };
339
340 static const struct tok bgp_origin_values[] = {
341 { 0, "IGP"},
342 { 1, "EGP"},
343 { 2, "Incomplete"},
344 { 0, NULL}
345 };
346
347 #define BGP_PMSI_TUNNEL_RSVP_P2MP 1
348 #define BGP_PMSI_TUNNEL_LDP_P2MP 2
349 #define BGP_PMSI_TUNNEL_PIM_SSM 3
350 #define BGP_PMSI_TUNNEL_PIM_SM 4
351 #define BGP_PMSI_TUNNEL_PIM_BIDIR 5
352 #define BGP_PMSI_TUNNEL_INGRESS 6
353 #define BGP_PMSI_TUNNEL_LDP_MP2MP 7
354
355 static const struct tok bgp_pmsi_tunnel_values[] = {
356 { BGP_PMSI_TUNNEL_RSVP_P2MP, "RSVP-TE P2MP LSP"},
357 { BGP_PMSI_TUNNEL_LDP_P2MP, "LDP P2MP LSP"},
358 { BGP_PMSI_TUNNEL_PIM_SSM, "PIM-SSM Tree"},
359 { BGP_PMSI_TUNNEL_PIM_SM, "PIM-SM Tree"},
360 { BGP_PMSI_TUNNEL_PIM_BIDIR, "PIM-Bidir Tree"},
361 { BGP_PMSI_TUNNEL_INGRESS, "Ingress Replication"},
362 { BGP_PMSI_TUNNEL_LDP_MP2MP, "LDP MP2MP LSP"},
363 { 0, NULL}
364 };
365
366 static const struct tok bgp_pmsi_flag_values[] = {
367 { 0x01, "Leaf Information required"},
368 { 0, NULL}
369 };
370
371 #define BGP_AIGP_TLV 1
372
373 static const struct tok bgp_aigp_values[] = {
374 { BGP_AIGP_TLV, "AIGP"},
375 { 0, NULL}
376 };
377
378 /* Subsequent address family identifier, RFC2283 section 7 */
379 #define SAFNUM_RES 0
380 #define SAFNUM_UNICAST 1
381 #define SAFNUM_MULTICAST 2
382 #define SAFNUM_UNIMULTICAST 3 /* deprecated now */
383 /* labeled BGP RFC3107 */
384 #define SAFNUM_LABUNICAST 4
385 /* RFC6514 */
386 #define SAFNUM_MULTICAST_VPN 5
387 /* draft-nalawade-kapoor-tunnel-safi */
388 #define SAFNUM_TUNNEL 64
389 /* RFC4761 */
390 #define SAFNUM_VPLS 65
391 /* RFC6037 */
392 #define SAFNUM_MDT 66
393 /* RFC7432 */
394 #define SAFNUM_EVPN 70
395 /* RFC4364 */
396 #define SAFNUM_VPNUNICAST 128
397 /* RFC6513 */
398 #define SAFNUM_VPNMULTICAST 129
399 #define SAFNUM_VPNUNIMULTICAST 130 /* deprecated now */
400 /* RFC4684 */
401 #define SAFNUM_RT_ROUTING_INFO 132
402
403 #define BGP_VPN_RD_LEN 8
404
405 static const struct tok bgp_safi_values[] = {
406 { SAFNUM_RES, "Reserved"},
407 { SAFNUM_UNICAST, "Unicast"},
408 { SAFNUM_MULTICAST, "Multicast"},
409 { SAFNUM_UNIMULTICAST, "Unicast+Multicast"},
410 { SAFNUM_LABUNICAST, "labeled Unicast"},
411 { SAFNUM_TUNNEL, "Tunnel"},
412 { SAFNUM_VPLS, "VPLS"},
413 { SAFNUM_MDT, "MDT"},
414 { SAFNUM_EVPN, "EVPN"},
415 { SAFNUM_VPNUNICAST, "labeled VPN Unicast"},
416 { SAFNUM_VPNMULTICAST, "labeled VPN Multicast"},
417 { SAFNUM_VPNUNIMULTICAST, "labeled VPN Unicast+Multicast"},
418 { SAFNUM_RT_ROUTING_INFO, "Route Target Routing Information"},
419 { SAFNUM_MULTICAST_VPN, "Multicast VPN"},
420 { 0, NULL }
421 };
422
423 /* well-known community */
424 #define BGP_COMMUNITY_NO_EXPORT 0xffffff01
425 #define BGP_COMMUNITY_NO_ADVERT 0xffffff02
426 #define BGP_COMMUNITY_NO_EXPORT_SUBCONFED 0xffffff03
427
428 /* Extended community type - RFC 4360 */
429 #define BGP_EXT_COM_RT_0 0x0002 /* Route Target,Format AS(2bytes):AN(4bytes) */
430 #define BGP_EXT_COM_RT_1 0x0102 /* Route Target,Format IP address:AN(2bytes) */
431 #define BGP_EXT_COM_RT_2 0x0202 /* Route Target,Format AN(4bytes):local(2bytes) */
432 #define BGP_EXT_COM_RO_0 0x0003 /* Route Origin,Format AS(2bytes):AN(4bytes) */
433 #define BGP_EXT_COM_RO_1 0x0103 /* Route Origin,Format IP address:AN(2bytes) */
434 #define BGP_EXT_COM_RO_2 0x0203 /* Route Origin,Format AN(4bytes):local(2bytes) */
435 #define BGP_EXT_COM_LINKBAND 0x4004 /* Link Bandwidth,Format AS(2B):Bandwidth(4B) */
436 /* rfc2547 bgp-mpls-vpns */
437 #define BGP_EXT_COM_VPN_ORIGIN 0x0005 /* OSPF Domain ID / VPN of Origin - draft-rosen-vpns-ospf-bgp-mpls */
438 #define BGP_EXT_COM_VPN_ORIGIN2 0x0105 /* duplicate - keep for backwards compatibility */
439 #define BGP_EXT_COM_VPN_ORIGIN3 0x0205 /* duplicate - keep for backwards compatibility */
440 #define BGP_EXT_COM_VPN_ORIGIN4 0x8005 /* duplicate - keep for backwards compatibility */
441
442 #define BGP_EXT_COM_OSPF_RTYPE 0x0306 /* OSPF Route Type,Format Area(4B):RouteType(1B):Options(1B) */
443 #define BGP_EXT_COM_OSPF_RTYPE2 0x8000 /* duplicate - keep for backwards compatibility */
444 #define BGP_EXT_COM_ENCAP 0x030c /* rfc5512 */
445
446 #define BGP_EXT_COM_OSPF_RID 0x0107 /* OSPF Router ID,Format RouterID(4B):Unused(2B) */
447 #define BGP_EXT_COM_OSPF_RID2 0x8001 /* duplicate - keep for backwards compatibility */
448
449 #define BGP_EXT_COM_L2INFO 0x800a /* draft-kompella-ppvpn-l2vpn */
450
451 #define BGP_EXT_COM_SOURCE_AS 0x0009 /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */
452 #define BGP_EXT_COM_VRF_RT_IMP 0x010b /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */
453 #define BGP_EXT_COM_L2VPN_RT_0 0x000a /* L2VPN Identifier,Format AS(2bytes):AN(4bytes) */
454 #define BGP_EXT_COM_L2VPN_RT_1 0xF10a /* L2VPN Identifier,Format IP address:AN(2bytes) */
455
456 /* https://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a00801eb09a.shtml */
457 #define BGP_EXT_COM_EIGRP_GEN 0x8800
458 #define BGP_EXT_COM_EIGRP_METRIC_AS_DELAY 0x8801
459 #define BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW 0x8802
460 #define BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU 0x8803
461 #define BGP_EXT_COM_EIGRP_EXT_REMAS_REMID 0x8804
462 #define BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC 0x8805
463
464 /* Optional Parameters */
465 #define BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH 255 /* Non-Ext OP Type */
466
467 static const struct tok bgp_extd_comm_flag_values[] = {
468 { 0x8000, "vendor-specific"},
469 { 0x4000, "non-transitive"},
470 { 0, NULL},
471 };
472
473 static const struct tok bgp_extd_comm_subtype_values[] = {
474 { BGP_EXT_COM_RT_0, "target"},
475 { BGP_EXT_COM_RT_1, "target"},
476 { BGP_EXT_COM_RT_2, "target"},
477 { BGP_EXT_COM_RO_0, "origin"},
478 { BGP_EXT_COM_RO_1, "origin"},
479 { BGP_EXT_COM_RO_2, "origin"},
480 { BGP_EXT_COM_LINKBAND, "link-BW"},
481 { BGP_EXT_COM_VPN_ORIGIN, "ospf-domain"},
482 { BGP_EXT_COM_VPN_ORIGIN2, "ospf-domain"},
483 { BGP_EXT_COM_VPN_ORIGIN3, "ospf-domain"},
484 { BGP_EXT_COM_VPN_ORIGIN4, "ospf-domain"},
485 { BGP_EXT_COM_OSPF_RTYPE, "ospf-route-type"},
486 { BGP_EXT_COM_OSPF_RTYPE2, "ospf-route-type"},
487 { BGP_EXT_COM_ENCAP, "encapsulation"},
488 { BGP_EXT_COM_OSPF_RID, "ospf-router-id"},
489 { BGP_EXT_COM_OSPF_RID2, "ospf-router-id"},
490 { BGP_EXT_COM_L2INFO, "layer2-info"},
491 { BGP_EXT_COM_EIGRP_GEN, "eigrp-general-route (flag, tag)" },
492 { BGP_EXT_COM_EIGRP_METRIC_AS_DELAY, "eigrp-route-metric (AS, delay)" },
493 { BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW, "eigrp-route-metric (reliability, nexthop, bandwidth)" },
494 { BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU, "eigrp-route-metric (load, MTU)" },
495 { BGP_EXT_COM_EIGRP_EXT_REMAS_REMID, "eigrp-external-route (remote-AS, remote-ID)" },
496 { BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC, "eigrp-external-route (remote-proto, remote-metric)" },
497 { BGP_EXT_COM_SOURCE_AS, "source-AS" },
498 { BGP_EXT_COM_VRF_RT_IMP, "vrf-route-import"},
499 { BGP_EXT_COM_L2VPN_RT_0, "l2vpn-id"},
500 { BGP_EXT_COM_L2VPN_RT_1, "l2vpn-id"},
501 { 0, NULL},
502 };
503
504 /* RFC RFC5512 BGP Tunnel Encapsulation Attribute Tunnel Types */
505 #define BGP_ENCAP_TUNNEL_L2TPV3_IP 1
506 #define BGP_ENCAP_TUNNEL_GRE 2
507 #define BGP_ENCAP_TUNNEL_TRANSMIT 3
508 #define BGP_ENCAP_TUNNEL_IPSEC 4
509 #define BGP_ENCAP_TUNNEL_IP_IPSEC 5
510 #define BGP_ENCAP_TUNNEL_MPLS_IP 6
511 #define BGP_ENCAP_TUNNEL_IP_IP 7
512 #define BGP_ENCAP_TUNNEL_VXLAN 8
513 #define BGP_ENCAP_TUNNEL_NVGRE 9
514 #define BGP_ENCAP_TUNNEL_MPLS 10
515 #define BGP_ENCAP_TUNNEL_MPLS_GRE 11
516 #define BGP_ENCAP_TUNNEL_VXLAN_GPE 12
517 #define BGP_ENCAP_TUNNEL_MPLS_UDP 13
518 #define BGP_ENCAP_TUNNEL_IPV6 14
519 #define BGP_ENCAP_TUNNEL_SR_TE 15
520 #define BGP_ENCAP_TUNNEL_BARE 16
521 #define BGP_ENCAP_TUNNEL_SR 17
522
523 static const struct tok bgp_extd_comm_encap_tunnel_values[] = {
524 { BGP_ENCAP_TUNNEL_L2TPV3_IP, "L2TPv3 over IP"},
525 { BGP_ENCAP_TUNNEL_GRE, "GRE"},
526 { BGP_ENCAP_TUNNEL_TRANSMIT, "Transmit Tunnel"},
527 { BGP_ENCAP_TUNNEL_IPSEC, "IPsec"},
528 { BGP_ENCAP_TUNNEL_IP_IPSEC, "IP in IP with IPsec"},
529 { BGP_ENCAP_TUNNEL_MPLS_IP, "MPLS in IP with IPsec"},
530 { BGP_ENCAP_TUNNEL_IP_IP, "IP in IP"},
531 { BGP_ENCAP_TUNNEL_VXLAN, "VXLAN"},
532 { BGP_ENCAP_TUNNEL_NVGRE, "NVGRE"},
533 { BGP_ENCAP_TUNNEL_MPLS, "MPLS"},
534 { BGP_ENCAP_TUNNEL_MPLS_GRE, "MPLS in GRE"},
535 { BGP_ENCAP_TUNNEL_VXLAN_GPE, "VXLAN GPE"},
536 { BGP_ENCAP_TUNNEL_MPLS_UDP, "MPLS in UDP"},
537 { BGP_ENCAP_TUNNEL_IPV6, "IPv6"},
538 { BGP_ENCAP_TUNNEL_SR_TE, "SR TE"},
539 { BGP_ENCAP_TUNNEL_BARE, "Bare"},
540 { BGP_ENCAP_TUNNEL_SR, "SR"},
541 { 0, NULL},
542 };
543
544 /* OSPF codes for BGP_EXT_COM_OSPF_RTYPE draft-rosen-vpns-ospf-bgp-mpls */
545 #define BGP_OSPF_RTYPE_RTR 1 /* OSPF Router LSA */
546 #define BGP_OSPF_RTYPE_NET 2 /* OSPF Network LSA */
547 #define BGP_OSPF_RTYPE_SUM 3 /* OSPF Summary LSA */
548 #define BGP_OSPF_RTYPE_EXT 5 /* OSPF External LSA, note that ASBR doesn't apply to MPLS-VPN */
549 #define BGP_OSPF_RTYPE_NSSA 7 /* OSPF NSSA External*/
550 #define BGP_OSPF_RTYPE_SHAM 129 /* OSPF-MPLS-VPN Sham link */
551 #define BGP_OSPF_RTYPE_METRIC_TYPE 0x1 /* LSB of RTYPE Options Field */
552
553 static const struct tok bgp_extd_comm_ospf_rtype_values[] = {
554 { BGP_OSPF_RTYPE_RTR, "Router" },
555 { BGP_OSPF_RTYPE_NET, "Network" },
556 { BGP_OSPF_RTYPE_SUM, "Summary" },
557 { BGP_OSPF_RTYPE_EXT, "External" },
558 { BGP_OSPF_RTYPE_NSSA,"NSSA External" },
559 { BGP_OSPF_RTYPE_SHAM,"MPLS-VPN Sham" },
560 { 0, NULL },
561 };
562
563 /* ADD-PATH Send/Receive field values */
564 static const struct tok bgp_add_path_recvsend[] = {
565 { 1, "Receive" },
566 { 2, "Send" },
567 { 3, "Both" },
568 { 0, NULL },
569 };
570
571 #define AS_STR_SIZE sizeof("xxxxx.xxxxx")
572
573 /*
574 * as_printf
575 *
576 * Convert an AS number into a string and return string pointer.
577 *
578 * Depending on bflag is set or not, AS number is converted into ASDOT notation
579 * or plain number notation.
580 *
581 */
582 static char *
583 as_printf(netdissect_options *ndo,
584 char *str, size_t size, u_int asnum)
585 {
586 if (!ndo->ndo_bflag || asnum <= 0xFFFF) {
587 snprintf(str, size, "%u", asnum);
588 } else {
589 snprintf(str, size, "%u.%u", asnum >> 16, asnum & 0xFFFF);
590 }
591 return str;
592 }
593
594 #define ITEMCHECK(minlen) if (itemlen < minlen) goto badtlv;
595
596 int
597 decode_prefix4(netdissect_options *ndo,
598 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
599 {
600 nd_ipv4 addr;
601 u_int plen, plenbytes;
602
603 ITEMCHECK(1);
604 plen = GET_U_1(pptr);
605 if (32 < plen)
606 return -1;
607 itemlen -= 1;
608
609 memset(&addr, 0, sizeof(addr));
610 plenbytes = (plen + 7) / 8;
611 ITEMCHECK(plenbytes);
612 GET_CPY_BYTES(&addr, pptr + 1, plenbytes);
613 if (plen % 8) {
614 ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
615 }
616 snprintf(buf, buflen, "%s/%u", ipaddr_string(ndo, (const u_char *)&addr), plen);
617 return 1 + plenbytes;
618
619 badtlv:
620 return -2;
621 }
622
623 static int
624 decode_labeled_prefix4(netdissect_options *ndo,
625 const u_char *pptr, u_int itemlen, char *buf,
626 size_t buflen)
627 {
628 nd_ipv4 addr;
629 u_int plen, plenbytes;
630
631 /* prefix length and label = 4 bytes */
632 ND_TCHECK_4(pptr);
633 ITEMCHECK(4);
634 plen = GET_U_1(pptr); /* get prefix length */
635
636 /* this is one of the weirdnesses of rfc3107
637 the label length (actually the label + COS bits)
638 is added to the prefix length;
639 we also do only read out just one label -
640 there is no real application for advertisement of
641 stacked labels in a single BGP message
642 */
643
644 if (24 > plen)
645 return -1;
646
647 plen-=24; /* adjust prefixlen - labellength */
648
649 if (32 < plen)
650 return -1;
651 itemlen -= 4;
652
653 memset(&addr, 0, sizeof(addr));
654 plenbytes = (plen + 7) / 8;
655 ITEMCHECK(plenbytes);
656 GET_CPY_BYTES(&addr, pptr + 4, plenbytes);
657 if (plen % 8) {
658 ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
659 }
660 /* the label may get offsetted by 4 bits so lets shift it right */
661 snprintf(buf, buflen, "%s/%u, label:%u %s",
662 ipaddr_string(ndo, (const u_char *)&addr),
663 plen,
664 GET_BE_U_3(pptr + 1)>>4,
665 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
666
667 return 4 + plenbytes;
668
669 trunc:
670 return -2;
671
672 badtlv:
673 return -3;
674 }
675
676 /*
677 * bgp_vpn_ip_print
678 *
679 * print an ipv4 or ipv6 address into a buffer dependent on address length.
680 */
681 static char *
682 bgp_vpn_ip_print(netdissect_options *ndo,
683 const u_char *pptr, u_int addr_length)
684 {
685
686 /* worst case string is s fully formatted v6 address */
687 static char addr[sizeof("1234:5678:89ab:cdef:1234:5678:89ab:cdef")];
688 char *pos = addr;
689
690 switch(addr_length) {
691 case (sizeof(nd_ipv4) << 3): /* 32 */
692 snprintf(pos, sizeof(addr), "%s", GET_IPADDR_STRING(pptr));
693 break;
694 case (sizeof(nd_ipv6) << 3): /* 128 */
695 snprintf(pos, sizeof(addr), "%s", GET_IP6ADDR_STRING(pptr));
696 break;
697 default:
698 snprintf(pos, sizeof(addr), "bogus address length %u", addr_length);
699 break;
700 }
701 pos += strlen(pos);
702
703 *(pos) = '\0';
704 return (addr);
705 }
706
707 /*
708 * bgp_vpn_sg_print
709 *
710 * print an multicast s,g entry into a buffer.
711 * the s,g entry is encoded like this.
712 *
713 * +-----------------------------------+
714 * | Multicast Source Length (1 octet) |
715 * +-----------------------------------+
716 * | Multicast Source (Variable) |
717 * +-----------------------------------+
718 * | Multicast Group Length (1 octet) |
719 * +-----------------------------------+
720 * | Multicast Group (Variable) |
721 * +-----------------------------------+
722 *
723 * return the number of bytes read from the wire.
724 */
725 static u_int
726 bgp_vpn_sg_print(netdissect_options *ndo,
727 const u_char *pptr, char *buf, size_t buflen)
728 {
729 uint8_t addr_length;
730 u_int total_length, offset;
731
732 total_length = 0;
733
734 /* Source address length, encoded in bits */
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 addr_length = GET_U_1(pptr);
750 pptr++;
751
752 /* Group address */
753 ND_TCHECK_LEN(pptr, (addr_length >> 3));
754 total_length += (addr_length >> 3) + 1;
755 offset = (u_int)strlen(buf);
756 if (addr_length) {
757 snprintf(buf + offset, buflen - offset, ", Group %s",
758 bgp_vpn_ip_print(ndo, pptr, addr_length));
759 pptr += (addr_length >> 3);
760 }
761
762 trunc:
763 return (total_length);
764 }
765
766 /* Print an RFC 4364 Route Distinguisher */
767 const char *
768 bgp_vpn_rd_print(netdissect_options *ndo,
769 const u_char *pptr)
770 {
771 /* allocate space for the largest possible string */
772 static char rd[sizeof("xxxxx.xxxxx:xxxxx (xxx.xxx.xxx.xxx:xxxxx)")];
773 char *pos = rd;
774 /* allocate space for the largest possible string */
775 char astostr[AS_STR_SIZE];
776
777 /* ok lets load the RD format */
778 switch (GET_BE_U_2(pptr)) {
779
780 case 0:
781 /* 2-byte-AS:number fmt */
782 snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (= %u.%u.%u.%u)",
783 GET_BE_U_2(pptr + 2),
784 GET_BE_U_4(pptr + 4),
785 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
786 GET_U_1(pptr + 6), GET_U_1(pptr + 7));
787 break;
788
789 case 1:
790 /* IP-address:AS fmt */
791 snprintf(pos, sizeof(rd) - (pos - rd), "%u.%u.%u.%u:%u",
792 GET_U_1(pptr + 2), GET_U_1(pptr + 3),
793 GET_U_1(pptr + 4), GET_U_1(pptr + 5),
794 GET_BE_U_2(pptr + 6));
795 break;
796
797 case 2:
798 /* 4-byte-AS:number fmt */
799 snprintf(pos, sizeof(rd) - (pos - rd), "%s:%u (%u.%u.%u.%u:%u)",
800 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 2)),
801 GET_BE_U_2(pptr + 6), GET_U_1(pptr + 2),
802 GET_U_1(pptr + 3), GET_U_1(pptr + 4),
803 GET_U_1(pptr + 5), GET_BE_U_2(pptr + 6));
804 break;
805 default:
806 snprintf(pos, sizeof(rd) - (pos - rd), "unknown RD format");
807 break;
808 }
809 pos += strlen(pos);
810 *(pos) = '\0';
811 return (rd);
812 }
813
814 /*
815 * Print an RFC 4360 Extended Community.
816 */
817 static void
818 bgp_extended_community_print(netdissect_options *ndo,
819 const u_char *pptr)
820 {
821 union { /* copy buffer for bandwidth values */
822 float f;
823 uint32_t i;
824 } bw;
825 /* allocate space for the largest possible string */
826 char astostr[AS_STR_SIZE];
827
828 switch (GET_BE_U_2(pptr)) {
829
830 case BGP_EXT_COM_RT_0:
831 case BGP_EXT_COM_RO_0:
832 case BGP_EXT_COM_L2VPN_RT_0:
833 ND_PRINT("%u:%u (= %s)",
834 GET_BE_U_2(pptr + 2),
835 GET_BE_U_4(pptr + 4),
836 GET_IPADDR_STRING(pptr+4));
837 break;
838
839 case BGP_EXT_COM_RT_1:
840 case BGP_EXT_COM_RO_1:
841 case BGP_EXT_COM_L2VPN_RT_1:
842 case BGP_EXT_COM_VRF_RT_IMP:
843 ND_PRINT("%s:%u",
844 GET_IPADDR_STRING(pptr+2),
845 GET_BE_U_2(pptr + 6));
846 break;
847
848 case BGP_EXT_COM_RT_2:
849 case BGP_EXT_COM_RO_2:
850 ND_PRINT("%s:%u",
851 as_printf(ndo, astostr, sizeof(astostr),
852 GET_BE_U_4(pptr + 2)), GET_BE_U_2(pptr + 6));
853 break;
854
855 case BGP_EXT_COM_LINKBAND:
856 bw.i = GET_BE_U_4(pptr + 4);
857 ND_PRINT("bandwidth: %.3f Mbps",
858 bw.f*8/1000000);
859 break;
860
861 case BGP_EXT_COM_VPN_ORIGIN:
862 case BGP_EXT_COM_VPN_ORIGIN2:
863 case BGP_EXT_COM_VPN_ORIGIN3:
864 case BGP_EXT_COM_VPN_ORIGIN4:
865 case BGP_EXT_COM_OSPF_RID:
866 case BGP_EXT_COM_OSPF_RID2:
867 ND_PRINT("%s", GET_IPADDR_STRING(pptr+2));
868 break;
869
870 case BGP_EXT_COM_OSPF_RTYPE:
871 case BGP_EXT_COM_OSPF_RTYPE2:
872 ND_PRINT("area:%s, router-type:%s, metric-type:%s%s",
873 GET_IPADDR_STRING(pptr+2),
874 tok2str(bgp_extd_comm_ospf_rtype_values,
875 "unknown (0x%02x)",
876 GET_U_1((pptr + 6))),
877 (GET_U_1(pptr + 7) & BGP_OSPF_RTYPE_METRIC_TYPE) ? "E2" : "",
878 ((GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_EXT) || (GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_NSSA)) ? "E1" : "");
879 break;
880
881 case BGP_EXT_COM_L2INFO:
882 ND_PRINT("%s Control Flags [0x%02x]:MTU %u",
883 tok2str(l2vpn_encaps_values,
884 "unknown encaps",
885 GET_U_1((pptr + 2))),
886 GET_U_1((pptr + 3)),
887 GET_BE_U_2(pptr + 4));
888 break;
889
890 case BGP_EXT_COM_SOURCE_AS:
891 ND_PRINT("AS %u", GET_BE_U_2(pptr + 2));
892 break;
893
894 case BGP_EXT_COM_ENCAP:
895 ND_PRINT("Tunnel type: %s", tok2str(bgp_extd_comm_encap_tunnel_values,
896 "unknown encaps",
897 GET_BE_U_2(pptr + 6)));
898 break;
899
900 default:
901 ND_PRINT("%02x%02x%02x%02x%02x%02x",
902 GET_U_1(pptr + 2),
903 GET_U_1(pptr + 3),
904 GET_U_1(pptr + 4),
905 GET_U_1(pptr + 5),
906 GET_U_1(pptr + 6),
907 GET_U_1(pptr + 7));
908 break;
909 }
910 }
911
912 /*
913 * RFC4684 (Section 4)/RFC2858 (Section 4).
914 * RTC membership prefix is structured as follows
915 * [prefix-len] [origin-as] [route-target]
916 * The route-target is encoded as RT ext-comms.
917 * Prefix-len may be 0, 32..96
918 *
919 * Note that pptr is not packet data - it is
920 * a buffer owned by our caller - therefore GET_*
921 * macros can not be used.
922 */
923 static char *
924 bgp_rt_prefix_print(netdissect_options *ndo,
925 const u_char *pptr,
926 u_int plen)
927 {
928 /* allocate space for the largest possible string */
929 char rtc_prefix_in_hex[sizeof("0000 0000 0000 0000")] = "";
930 u_int rtc_prefix_in_hex_len = 0;
931 static char output[61]; /* max response string */
932 /* allocate space for the largest possible string */
933 char astostr[AS_STR_SIZE];
934 uint16_t ec_type = 0;
935 u_int octet_count;
936 u_int i;
937
938 if (plen == 0) {
939 snprintf(output, sizeof(output), "route-target: 0:0/0");
940 return (output);
941 }
942
943 /* hex representation of the prefix */
944 octet_count = (plen+7)/8;
945 for (i=0; i<octet_count; i++) {
946 rtc_prefix_in_hex_len += snprintf(rtc_prefix_in_hex+rtc_prefix_in_hex_len,
947 sizeof(rtc_prefix_in_hex)-rtc_prefix_in_hex_len,
948 "%02x%s", *(pptr+i),
949 ((i%2 == 1) && (i<octet_count-1)) ? " " : "");
950 }
951
952 if (plen < 16) {
953 /*
954 * The prefix is too short to include the full ext-comm type,
955 * so we have no way to parse it further.
956 */
957 snprintf(output, sizeof(output), "route-target: partial-type: (%s/%d)",
958 rtc_prefix_in_hex, plen);
959 return (output);
960 }
961
962 /*
963 * get the ext-comm type
964 * Note: pptr references a static 8 octet buffer with unused bits set to 0,
965 * hense EXTRACT_*() macros are safe.
966 */
967 ec_type = EXTRACT_BE_U_2(pptr);
968 switch (ec_type) {
969 case BGP_EXT_COM_RT_0:
970 /* 2-byte-AS:number fmt */
971 snprintf(output, sizeof(output), "route-target: %u:%u/%d (%s)",
972 EXTRACT_BE_U_2(pptr+2),
973 EXTRACT_BE_U_4(pptr+4),
974 plen, rtc_prefix_in_hex);
975 break;
976
977 case BGP_EXT_COM_RT_1:
978 /* IP-address:AS fmt */
979 snprintf(output, sizeof(output), "route-target: %u.%u.%u.%u:%u/%d (%s)",
980 *(pptr+2), *(pptr+3), *(pptr+4), *(pptr+5),
981 EXTRACT_BE_U_2(pptr+6), plen, rtc_prefix_in_hex);
982 break;
983
984 case BGP_EXT_COM_RT_2:
985 /* 4-byte-AS:number fmt */
986 snprintf(output, sizeof(output), "route-target: %s:%u/%d (%s)",
987 as_printf(ndo, astostr, sizeof(astostr), EXTRACT_BE_U_4(pptr+2)),
988 EXTRACT_BE_U_2(pptr+6), plen, rtc_prefix_in_hex);
989 break;
990
991 default:
992 snprintf(output, sizeof(output), "route target: unknown-type(%04x) (%s/%d)",
993 ec_type,
994 rtc_prefix_in_hex, plen);
995 break;
996 }
997 return (output);
998 }
999
1000 /* RFC 4684 */
1001 static int
1002 decode_rt_routing_info(netdissect_options *ndo,
1003 const u_char *pptr)
1004 {
1005 uint8_t route_target[8];
1006 u_int plen;
1007 /* allocate space for the largest possible string */
1008 char astostr[AS_STR_SIZE];
1009 u_int num_octets;
1010
1011 /* NLRI "prefix length" from RFC 2858 Section 4. */
1012 plen = GET_U_1(pptr); /* get prefix length */
1013
1014 /* NLRI "prefix" (ibid), valid lengths are { 0, 32, 33, ..., 96 } bits.
1015 * RFC 4684 Section 4 defines the layout of "origin AS" and "route
1016 * target" fields inside the "prefix" depending on its length.
1017 */
1018 if (0 == plen) {
1019 /* Without "origin AS", without "route target". */
1020 ND_PRINT("\n\t default route target");
1021 return 1;
1022 }
1023
1024 if (32 > plen) {
1025 ND_PRINT("\n\t (illegal prefix length)");
1026 return -1;
1027 }
1028
1029 /* With at least "origin AS", possibly with "route target". */
1030 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 1));
1031
1032 plen -= 32; /* adjust prefix length */
1033
1034 if (64 < plen) {
1035 ND_PRINT("\n\t (illegal prefix length)");
1036 return -1;
1037 }
1038
1039 /* From now on (plen + 7) / 8 evaluates to { 0, 1, 2, ..., 8 }
1040 * and gives the number of octets in the variable-length "route
1041 * target" field inside this NLRI "prefix". Look for it.
1042 */
1043 memset(&route_target, 0, sizeof(route_target));
1044 num_octets = (plen + 7) / 8;
1045 GET_CPY_BYTES(&route_target, pptr + 5, num_octets);
1046 /* If mask-len is not on octet boundary, ensure all extra bits are 0 */
1047 if (plen % 8) {
1048 ((u_char *)&route_target)[num_octets - 1] &=
1049 ((0xff00 >> (plen % 8)) & 0xff);
1050 }
1051 ND_PRINT("\n\t origin AS: %s, %s",
1052 astostr,
1053 bgp_rt_prefix_print(ndo, (u_char *)&route_target, plen));
1054
1055 return 5 + num_octets;
1056 }
1057
1058 static int
1059 decode_labeled_vpn_prefix4(netdissect_options *ndo,
1060 const u_char *pptr, char *buf, size_t buflen)
1061 {
1062 nd_ipv4 addr;
1063 u_int plen;
1064
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 GET_CPY_BYTES(&addr, pptr + 12, (plen + 7) / 8);
1077 if (plen % 8) {
1078 ((u_char *)&addr)[(plen + 7) / 8 - 1] &=
1079 ((0xff00 >> (plen % 8)) & 0xff);
1080 }
1081 /* the label may get offsetted by 4 bits so lets shift it right */
1082 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1083 bgp_vpn_rd_print(ndo, pptr+4),
1084 ipaddr_string(ndo, (const u_char *)&addr),
1085 plen,
1086 GET_BE_U_3(pptr + 1)>>4,
1087 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1088
1089 return 12 + (plen + 7) / 8;
1090 }
1091
1092 /*
1093 * +-------------------------------+
1094 * | |
1095 * | RD:IPv4-address (12 octets) |
1096 * | |
1097 * +-------------------------------+
1098 * | MDT Group-address (4 octets) |
1099 * +-------------------------------+
1100 */
1101
1102 #define MDT_VPN_NLRI_LEN 16
1103
1104 static int
1105 decode_mdt_vpn_nlri(netdissect_options *ndo,
1106 const u_char *pptr, char *buf, size_t buflen)
1107 {
1108 const u_char *rd;
1109 const u_char *vpn_ip;
1110
1111 /* if the NLRI is not predefined length, quit.*/
1112 if (GET_U_1(pptr) != MDT_VPN_NLRI_LEN * 8)
1113 return -1;
1114 pptr++;
1115
1116 /* RD */
1117 ND_TCHECK_8(pptr);
1118 rd = pptr;
1119 pptr += 8;
1120
1121 /* IPv4 address */
1122 vpn_ip = pptr;
1123 pptr += sizeof(nd_ipv4);
1124
1125 /* MDT Group Address */
1126 snprintf(buf, buflen, "RD: %s, VPN IP Address: %s, MC Group Address: %s",
1127 bgp_vpn_rd_print(ndo, rd), GET_IPADDR_STRING(vpn_ip), GET_IPADDR_STRING(pptr));
1128
1129 return MDT_VPN_NLRI_LEN + 1;
1130
1131 trunc:
1132 return -2;
1133 }
1134
1135 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI 1
1136 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI 2
1137 #define BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI 3
1138 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF 4
1139 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE 5
1140 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN 6
1141 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN 7
1142
1143 static const struct tok bgp_multicast_vpn_route_type_values[] = {
1144 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI, "Intra-AS I-PMSI"},
1145 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI, "Inter-AS I-PMSI"},
1146 { BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI, "S-PMSI"},
1147 { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF, "Intra-AS Segment-Leaf"},
1148 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE, "Source-Active"},
1149 { BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN, "Shared Tree Join"},
1150 { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN, "Source Tree Join"},
1151 { 0, NULL}
1152 };
1153
1154 static int
1155 decode_multicast_vpn(netdissect_options *ndo,
1156 const u_char *pptr, char *buf, size_t buflen)
1157 {
1158 /* allocate space for the largest possible string */
1159 char astostr[AS_STR_SIZE];
1160 uint8_t route_type, route_length;
1161 u_int addr_length, sg_length;
1162 u_int offset;
1163
1164 route_type = GET_U_1(pptr);
1165 pptr++;
1166 route_length = GET_U_1(pptr);
1167 pptr++;
1168
1169 snprintf(buf, buflen, "Route-Type: %s (%u), length: %u",
1170 tok2str(bgp_multicast_vpn_route_type_values,
1171 "Unknown", route_type),
1172 route_type, route_length);
1173
1174 switch(route_type) {
1175 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI:
1176 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1177 offset = (u_int)strlen(buf);
1178 snprintf(buf + offset, buflen - offset, ", RD: %s, Originator %s",
1179 bgp_vpn_rd_print(ndo, pptr),
1180 bgp_vpn_ip_print(ndo, pptr + BGP_VPN_RD_LEN,
1181 (route_length - BGP_VPN_RD_LEN) << 3));
1182 break;
1183 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI:
1184 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1185 offset = (u_int)strlen(buf);
1186 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1187 bgp_vpn_rd_print(ndo, pptr),
1188 as_printf(ndo, astostr, sizeof(astostr),
1189 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1190 break;
1191
1192 case BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI:
1193 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1194 offset = (u_int)strlen(buf);
1195 snprintf(buf + offset, buflen - offset, ", RD: %s",
1196 bgp_vpn_rd_print(ndo, pptr));
1197 pptr += BGP_VPN_RD_LEN;
1198
1199 sg_length = bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1200 addr_length = route_length - sg_length;
1201
1202 ND_TCHECK_LEN(pptr, addr_length);
1203 offset = (u_int)strlen(buf);
1204 snprintf(buf + offset, buflen - offset, ", Originator %s",
1205 bgp_vpn_ip_print(ndo, pptr, addr_length << 3));
1206 break;
1207
1208 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE:
1209 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN);
1210 offset = (u_int)strlen(buf);
1211 snprintf(buf + offset, buflen - offset, ", RD: %s",
1212 bgp_vpn_rd_print(ndo, pptr));
1213 pptr += BGP_VPN_RD_LEN;
1214
1215 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1216 break;
1217
1218 case BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN: /* fall through */
1219 case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN:
1220 ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4);
1221 offset = (u_int)strlen(buf);
1222 snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s",
1223 bgp_vpn_rd_print(ndo, pptr),
1224 as_printf(ndo, astostr, sizeof(astostr),
1225 GET_BE_U_4(pptr + BGP_VPN_RD_LEN)));
1226 pptr += BGP_VPN_RD_LEN + 4;
1227
1228 bgp_vpn_sg_print(ndo, pptr, buf, buflen);
1229 break;
1230
1231 /*
1232 * no per route-type printing yet.
1233 */
1234 case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF:
1235 default:
1236 break;
1237 }
1238
1239 return route_length + 2;
1240
1241 trunc:
1242 return -2;
1243 }
1244
1245 /*
1246 * As I remember, some versions of systems have an snprintf() that
1247 * returns -1 if the buffer would have overflowed. If the return
1248 * value is negative, set buflen to 0, to indicate that we've filled
1249 * the buffer up.
1250 *
1251 * If the return value is greater than buflen, that means that
1252 * the buffer would have overflowed; again, set buflen to 0 in
1253 * that case.
1254 */
1255 #define UPDATE_BUF_BUFLEN(buf, buflen, stringlen) \
1256 if (stringlen<0) \
1257 buflen=0; \
1258 else if ((u_int)stringlen>buflen) \
1259 buflen=0; \
1260 else { \
1261 buflen-=stringlen; \
1262 buf+=stringlen; \
1263 }
1264
1265 static int
1266 decode_labeled_vpn_l2(netdissect_options *ndo,
1267 const u_char *pptr, char *buf, size_t buflen)
1268 {
1269 u_int plen, tlen, tlv_type, tlv_len, ttlv_len;
1270 int stringlen;
1271
1272 plen = GET_BE_U_2(pptr);
1273 tlen = plen;
1274 pptr += 2;
1275 /* Old and new L2VPN NLRI share AFI/SAFI
1276 * -> Assume a 12 Byte-length NLRI is auto-discovery-only
1277 * and > 17 as old format. Complain for the middle case
1278 */
1279 if (plen == 12) {
1280 /* assume AD-only with RD, BGPNH */
1281 ND_TCHECK_LEN(pptr, 12);
1282 buf[0] = '\0';
1283 stringlen = snprintf(buf, buflen, "RD: %s, BGPNH: %s",
1284 bgp_vpn_rd_print(ndo, pptr),
1285 GET_IPADDR_STRING(pptr+8));
1286 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1287 pptr += 12;
1288 tlen -= 12;
1289 return plen + 2;
1290 } else if (plen > 17) {
1291 /* assume old format */
1292 /* RD, ID, LBLKOFF, LBLBASE */
1293
1294 ND_TCHECK_LEN(pptr, 15);
1295 buf[0] = '\0';
1296 stringlen = snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u",
1297 bgp_vpn_rd_print(ndo, pptr),
1298 GET_BE_U_2(pptr + 8),
1299 GET_BE_U_2(pptr + 10),
1300 GET_BE_U_3(pptr + 12)>>4); /* the label is offsetted by 4 bits so lets shift it right */
1301 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1302 pptr += 15;
1303 tlen -= 15;
1304
1305 /* ok now the variable part - lets read out TLVs*/
1306 while (tlen != 0) {
1307 if (tlen < 3) {
1308 if (buflen != 0) {
1309 stringlen=snprintf(buf,buflen, "\n\t\tran past the end");
1310 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1311 }
1312 return plen + 2;
1313 }
1314 tlv_type = GET_U_1(pptr);
1315 pptr++;
1316 tlv_len = GET_BE_U_2(pptr); /* length, in *bits* */
1317 ttlv_len = (tlv_len + 7)/8; /* length, in *bytes* */
1318 pptr += 2;
1319
1320 switch(tlv_type) {
1321 case 1:
1322 if (buflen != 0) {
1323 stringlen=snprintf(buf,buflen, "\n\t\tcircuit status vector (%u) length: %u: 0x",
1324 tlv_type,
1325 tlv_len);
1326 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1327 }
1328 while (ttlv_len != 0) {
1329 if (tlen < 1) {
1330 if (buflen != 0) {
1331 stringlen=snprintf(buf,buflen, " (ran past the end)");
1332 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1333 }
1334 return plen + 2;
1335 }
1336 ND_TCHECK_1(pptr);
1337 if (buflen != 0) {
1338 stringlen=snprintf(buf,buflen, "%02x",
1339 GET_U_1(pptr));
1340 pptr++;
1341 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1342 }
1343 ttlv_len--;
1344 tlen--;
1345 }
1346 break;
1347 default:
1348 if (buflen != 0) {
1349 stringlen=snprintf(buf,buflen, "\n\t\tunknown TLV #%u, length: %u",
1350 tlv_type,
1351 tlv_len);
1352 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1353 }
1354 if (tlen < ttlv_len) {
1355 if (buflen != 0) {
1356 stringlen=snprintf(buf,buflen, " (ran past the end)");
1357 UPDATE_BUF_BUFLEN(buf, buflen, stringlen);
1358 }
1359 return plen + 2;
1360 }
1361 tlen -= ttlv_len;
1362 break;
1363 }
1364 }
1365 return plen + 2;
1366 } else {
1367 /* complain bitterly ? */
1368 /* fall through */
1369 goto trunc;
1370 }
1371
1372 trunc:
1373 return -2;
1374 }
1375
1376 int
1377 decode_prefix6(netdissect_options *ndo,
1378 const u_char *pd, u_int itemlen, char *buf, size_t buflen)
1379 {
1380 nd_ipv6 addr;
1381 u_int plen, plenbytes;
1382
1383 ITEMCHECK(1);
1384 plen = GET_U_1(pd);
1385 if (128 < plen)
1386 return -1;
1387 itemlen -= 1;
1388
1389 memset(&addr, 0, sizeof(addr));
1390 plenbytes = (plen + 7) / 8;
1391 ITEMCHECK(plenbytes);
1392 GET_CPY_BYTES(&addr, pd + 1, plenbytes);
1393 if (plen % 8) {
1394 addr[plenbytes - 1] &=
1395 ((0xff00 >> (plen % 8)) & 0xff);
1396 }
1397 snprintf(buf, buflen, "%s/%u", ip6addr_string(ndo, (const u_char *)&addr), plen);
1398 return 1 + plenbytes;
1399
1400 badtlv:
1401 return -2;
1402 }
1403
1404 static int
1405 decode_labeled_prefix6(netdissect_options *ndo,
1406 const u_char *pptr, u_int itemlen, char *buf, size_t buflen)
1407 {
1408 nd_ipv6 addr;
1409 u_int plen, plenbytes;
1410
1411 /* prefix length and label = 4 bytes */
1412 ND_TCHECK_4(pptr);
1413 ITEMCHECK(4);
1414 plen = GET_U_1(pptr); /* get prefix length */
1415
1416 if (24 > plen)
1417 return -1;
1418
1419 plen -= 24; /* adjust prefixlen - labellength */
1420
1421 if (128 < plen)
1422 return -1;
1423 itemlen -= 4;
1424
1425 memset(&addr, 0, sizeof(addr));
1426 plenbytes = (plen + 7) / 8;
1427 GET_CPY_BYTES(&addr, pptr + 4, plenbytes);
1428 if (plen % 8) {
1429 addr[plenbytes - 1] &=
1430 ((0xff00 >> (plen % 8)) & 0xff);
1431 }
1432 /* the label may get offsetted by 4 bits so lets shift it right */
1433 snprintf(buf, buflen, "%s/%u, label:%u %s",
1434 ip6addr_string(ndo, (const u_char *)&addr),
1435 plen,
1436 GET_BE_U_3(pptr + 1)>>4,
1437 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1438
1439 return 4 + plenbytes;
1440
1441 trunc:
1442 return -2;
1443
1444 badtlv:
1445 return -3;
1446 }
1447
1448 static int
1449 decode_labeled_vpn_prefix6(netdissect_options *ndo,
1450 const u_char *pptr, char *buf, size_t buflen)
1451 {
1452 nd_ipv6 addr;
1453 u_int plen;
1454
1455 plen = GET_U_1(pptr); /* get prefix length */
1456
1457 if ((24+64) > plen)
1458 return -1;
1459
1460 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1461
1462 if (128 < plen)
1463 return -1;
1464
1465 memset(&addr, 0, sizeof(addr));
1466 GET_CPY_BYTES(&addr, pptr + 12, (plen + 7) / 8);
1467 if (plen % 8) {
1468 addr[(plen + 7) / 8 - 1] &=
1469 ((0xff00 >> (plen % 8)) & 0xff);
1470 }
1471 /* the label may get offsetted by 4 bits so lets shift it right */
1472 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1473 bgp_vpn_rd_print(ndo, pptr+4),
1474 ip6addr_string(ndo, (const u_char *)&addr),
1475 plen,
1476 GET_BE_U_3(pptr + 1)>>4,
1477 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1478
1479 return 12 + (plen + 7) / 8;
1480 }
1481
1482 static int
1483 decode_clnp_prefix(netdissect_options *ndo,
1484 const u_char *pptr, char *buf, size_t buflen)
1485 {
1486 uint8_t addr[19];
1487 u_int plen;
1488
1489 plen = GET_U_1(pptr); /* get prefix length */
1490
1491 if (152 < plen)
1492 return -1;
1493
1494 memset(&addr, 0, sizeof(addr));
1495 GET_CPY_BYTES(&addr, pptr + 4, (plen + 7) / 8);
1496 if (plen % 8) {
1497 addr[(plen + 7) / 8 - 1] &=
1498 ((0xff00 >> (plen % 8)) & 0xff);
1499 }
1500 /* Cannot use GET_ISONSAP_STRING (not packet buffer pointer) */
1501 snprintf(buf, buflen, "%s/%u",
1502 isonsap_string(ndo, addr,(plen + 7) / 8),
1503 plen);
1504
1505 return 1 + (plen + 7) / 8;
1506 }
1507
1508 static int
1509 decode_labeled_vpn_clnp_prefix(netdissect_options *ndo,
1510 const u_char *pptr, char *buf, size_t buflen)
1511 {
1512 uint8_t addr[19];
1513 u_int plen;
1514
1515 plen = GET_U_1(pptr); /* get prefix length */
1516
1517 if ((24+64) > plen)
1518 return -1;
1519
1520 plen -= (24+64); /* adjust prefixlen - labellength - RD len*/
1521
1522 if (152 < plen)
1523 return -1;
1524
1525 memset(&addr, 0, sizeof(addr));
1526 GET_CPY_BYTES(&addr, pptr + 12, (plen + 7) / 8);
1527 if (plen % 8) {
1528 addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff);
1529 }
1530 /* the label may get offsetted by 4 bits so lets shift it right */
1531 /* Cannot use GET_ISONSAP_STRING (not packet buffer pointer) */
1532 snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s",
1533 bgp_vpn_rd_print(ndo, pptr+4),
1534 isonsap_string(ndo, addr,(plen + 7) / 8),
1535 plen,
1536 GET_BE_U_3(pptr + 1)>>4,
1537 ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" );
1538
1539 return 12 + (plen + 7) / 8;
1540 }
1541
1542 /*
1543 * bgp_attr_get_as_size
1544 *
1545 * Try to find the size of the ASs encoded in an as-path. It is not obvious, as
1546 * both Old speakers that do not support 4 byte AS, and the new speakers that do
1547 * support, exchange AS-Path with the same path-attribute type value 0x02.
1548 */
1549 static u_int
1550 bgp_attr_get_as_size(netdissect_options *ndo,
1551 uint8_t bgpa_type, const u_char *pptr, u_int len)
1552 {
1553 const u_char *tptr = pptr;
1554
1555 /*
1556 * If the path attribute is the optional AS4 path type, then we already
1557 * know, that ASs must be encoded in 4 byte format.
1558 */
1559 if (bgpa_type == BGPTYPE_AS4_PATH) {
1560 return 4;
1561 }
1562
1563 /*
1564 * Let us assume that ASs are of 2 bytes in size, and check if the AS-Path
1565 * TLV is good. If not, ask the caller to try with AS encoded as 4 bytes
1566 * each.
1567 */
1568 while (tptr < pptr + len) {
1569 /*
1570 * If we do not find a valid segment type, our guess might be wrong.
1571 */
1572 if (GET_U_1(tptr) < BGP_AS_SEG_TYPE_MIN || GET_U_1(tptr) > BGP_AS_SEG_TYPE_MAX) {
1573 goto trunc;
1574 }
1575 tptr += 2 + GET_U_1(tptr + 1) * 2;
1576 }
1577
1578 /*
1579 * If we correctly reached end of the AS path attribute data content,
1580 * then most likely ASs were indeed encoded as 2 bytes.
1581 */
1582 if (tptr == pptr + len) {
1583 return 2;
1584 }
1585
1586 trunc:
1587
1588 /*
1589 * We can come here, either we did not have enough data, or if we
1590 * try to decode 4 byte ASs in 2 byte format. Either way, return 4,
1591 * so that calller can try to decode each AS as of 4 bytes. If indeed
1592 * there was not enough data, it will crib and end the parse anyways.
1593 */
1594 return 4;
1595 }
1596
1597 /*
1598 * The only way to know that a BGP UPDATE message is using add path is
1599 * by checking if the capability is in the OPEN message which we may have missed.
1600 * So this function checks if it is possible that the update could contain add path
1601 * and if so it checks that standard BGP doesn't make sense.
1602 */
1603 static int
1604 check_add_path(netdissect_options *ndo, const u_char *pptr, u_int length,
1605 u_int max_prefix_length)
1606 {
1607 u_int offset, prefix_length;
1608
1609 if (length < 5) {
1610 return 0;
1611 }
1612
1613 /*
1614 * Scan through the NLRI information under the assumpetion that
1615 * it doesn't have path IDs.
1616 */
1617 for (offset = 0; offset < length;) {
1618 offset += 4;
1619 if (!ND_TTEST_1(pptr + offset)) {
1620 /* We ran out of captured data; quit scanning. */
1621 break;
1622 }
1623 prefix_length = GET_U_1(pptr + offset);
1624 /*
1625 * Add 4 to cover the path id
1626 * and check the prefix length isn't greater than 32/128.
1627 */
1628 if (prefix_length > max_prefix_length) {
1629 return 0;
1630 }
1631 /* Add 1 for the prefix_length byte and prefix_length to cover the address */
1632 offset += 1 + ((prefix_length + 7) / 8);
1633 }
1634 /* check we haven't gone past the end of the section */
1635 if (offset > length) {
1636 return 0;
1637 }
1638
1639 /* check it's not standard BGP */
1640 for (offset = 0; offset < length; ) {
1641 if (!ND_TTEST_1(pptr + offset)) {
1642 /* We ran out of captured data; quit scanning. */
1643 break;
1644 }
1645 prefix_length = GET_U_1(pptr + offset);
1646 /*
1647 * If the prefix_length is zero (0.0.0.0/0)
1648 * and since it's not the only address (length >= 5)
1649 * then it is add-path
1650 */
1651 if (prefix_length < 1 || prefix_length > max_prefix_length) {
1652 return 1;
1653 }
1654 offset += 1 + ((prefix_length + 7) / 8);
1655 }
1656 if (offset > length) {
1657 return 1;
1658 }
1659
1660 /* assume not add-path by default */
1661 return 0;
1662 }
1663
1664 static int
1665 bgp_mp_af_print(netdissect_options *ndo,
1666 const u_char *tptr, u_int tlen,
1667 uint16_t *afp, uint8_t *safip)
1668 {
1669 uint16_t af;
1670 uint8_t safi;
1671
1672 af = GET_BE_U_2(tptr);
1673 *afp = af;
1674 safi = GET_U_1(tptr + 2);
1675 *safip = safi;
1676
1677 ND_PRINT("\n\t AFI: %s (%u), %sSAFI: %s (%u)",
1678 tok2str(af_values, "Unknown AFI", af),
1679 af,
1680 (safi>128) ? "vendor specific " : "", /* 128 is meanwhile wellknown */
1681 tok2str(bgp_safi_values, "Unknown SAFI", safi),
1682 safi);
1683
1684 switch(af<<8 | safi) {
1685 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1686 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1687 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1688 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1689 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1690 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1691 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1692 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1693 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
1694 case (AFNUM_INET<<8 | SAFNUM_MDT):
1695 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1696 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1697 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1698 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1699 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1700 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1701 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1702 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1703 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1704 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1705 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1706 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1707 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1708 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1709 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1710 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1711 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1712 break;
1713 default:
1714 ND_TCHECK_LEN(tptr, tlen);
1715 ND_PRINT("\n\t no AFI %u / SAFI %u decoder", af, safi);
1716 if (ndo->ndo_vflag <= 1)
1717 print_unknown_data(ndo, tptr, "\n\t ", tlen);
1718 return -1;
1719 }
1720 return 0;
1721 trunc:
1722 return -2;
1723 }
1724
1725 static int
1726 bgp_nlri_print(netdissect_options *ndo, uint16_t af, uint8_t safi,
1727 const u_char *tptr, u_int len,
1728 char *buf, size_t buflen,
1729 int add_path4, int add_path6)
1730 {
1731 int advance;
1732 u_int path_id = 0;
1733
1734 switch (af<<8 | safi) {
1735 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
1736 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
1737 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
1738 if (add_path4) {
1739 path_id = GET_BE_U_4(tptr);
1740 tptr += 4;
1741 }
1742 advance = decode_prefix4(ndo, tptr, len, buf, buflen);
1743 if (advance == -1)
1744 ND_PRINT("\n\t (illegal prefix length)");
1745 else if (advance == -2)
1746 break; /* bytes left, but not enough */
1747 else
1748 ND_PRINT("\n\t %s", buf);
1749 if (add_path4) {
1750 ND_PRINT(" Path Id: %u", path_id);
1751 advance += 4;
1752 }
1753 break;
1754 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
1755 advance = decode_labeled_prefix4(ndo, tptr, len, buf, buflen);
1756 if (advance == -1)
1757 ND_PRINT("\n\t (illegal prefix length)");
1758 else if (advance == -2)
1759 goto trunc;
1760 else if (advance == -3)
1761 break; /* bytes left, but not enough */
1762 else
1763 ND_PRINT("\n\t %s", buf);
1764 break;
1765 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
1766 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
1767 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
1768 advance = decode_labeled_vpn_prefix4(ndo, tptr, buf, buflen);
1769 if (advance == -1)
1770 ND_PRINT("\n\t (illegal prefix length)");
1771 else
1772 ND_PRINT("\n\t %s", buf);
1773 break;
1774 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
1775 advance = decode_rt_routing_info(ndo, tptr);
1776 break;
1777 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN): /* fall through */
1778 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST_VPN):
1779 advance = decode_multicast_vpn(ndo, tptr, buf, buflen);
1780 if (advance == -1)
1781 ND_PRINT("\n\t (illegal prefix length)");
1782 else if (advance == -2)
1783 goto trunc;
1784 else
1785 ND_PRINT("\n\t %s", buf);
1786 break;
1787
1788 case (AFNUM_INET<<8 | SAFNUM_MDT):
1789 advance = decode_mdt_vpn_nlri(ndo, tptr, buf, buflen);
1790 if (advance == -1)
1791 ND_PRINT("\n\t (illegal prefix length)");
1792 else if (advance == -2)
1793 goto trunc;
1794 else
1795 ND_PRINT("\n\t %s", buf);
1796 break;
1797 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
1798 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
1799 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
1800 if (add_path6) {
1801 path_id = GET_BE_U_4(tptr);
1802 tptr += 4;
1803 }
1804 advance = decode_prefix6(ndo, tptr, len, buf, buflen);
1805 if (advance == -1)
1806 ND_PRINT("\n\t (illegal prefix length)");
1807 else if (advance == -2)
1808 break; /* bytes left, but not enough */
1809 else
1810 ND_PRINT("\n\t %s", buf);
1811 if (add_path6) {
1812 ND_PRINT(" Path Id: %u", path_id);
1813 advance += 4;
1814 }
1815 break;
1816 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
1817 advance = decode_labeled_prefix6(ndo, tptr, len, buf, buflen);
1818 if (advance == -1)
1819 ND_PRINT("\n\t (illegal prefix length)");
1820 else if (advance == -2)
1821 goto trunc;
1822 else if (advance == -3)
1823 break; /* bytes left, but not enough */
1824 else
1825 ND_PRINT("\n\t %s", buf);
1826 break;
1827 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
1828 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
1829 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
1830 advance = decode_labeled_vpn_prefix6(ndo, tptr, buf, buflen);
1831 if (advance == -1)
1832 ND_PRINT("\n\t (illegal prefix length)");
1833 else
1834 ND_PRINT("\n\t %s", buf);
1835 break;
1836 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
1837 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
1838 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
1839 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
1840 advance = decode_labeled_vpn_l2(ndo, tptr, buf, buflen);
1841 if (advance == -1)
1842 ND_PRINT("\n\t (illegal length)");
1843 else if (advance == -2)
1844 goto trunc;
1845 else
1846 ND_PRINT("\n\t %s", buf);
1847 break;
1848 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
1849 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
1850 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
1851 advance = decode_clnp_prefix(ndo, tptr, buf, buflen);
1852 if (advance == -1)
1853 ND_PRINT("\n\t (illegal prefix length)");
1854 else
1855 ND_PRINT("\n\t %s", buf);
1856 break;
1857 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
1858 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
1859 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
1860 advance = decode_labeled_vpn_clnp_prefix(ndo, tptr, buf, buflen);
1861 if (advance == -1)
1862 ND_PRINT("\n\t (illegal prefix length)");
1863 else
1864 ND_PRINT("\n\t %s", buf);
1865 break;
1866 default:
1867 /*
1868 * This should not happen, we should have been protected
1869 * by bgp_mp_af_print()'s return value.
1870 */
1871 ND_PRINT("\n\t ERROR: no AFI %u / SAFI %u decoder", af, safi);
1872 advance = -4;
1873 break;
1874 }
1875 return advance;
1876 trunc: /* we rely on the caller to recognize -2 return value */
1877 return -2;
1878 }
1879
1880 static int
1881 bgp_attr_print(netdissect_options *ndo,
1882 uint8_t atype, const u_char *pptr, u_int len,
1883 const unsigned attr_set_level)
1884 {
1885 /* allocate space for the largest possible string */
1886 char astostr[AS_STR_SIZE];
1887 u_int i;
1888 uint16_t af;
1889 uint8_t safi, snpa, nhlen;
1890 int advance;
1891 u_int tlen;
1892 const u_char *tptr;
1893 char buf[MAXHOSTNAMELEN + 100];
1894 u_int as_size;
1895 int add_path4, add_path6;
1896 int ret;
1897
1898 tptr = pptr;
1899 tlen = len;
1900
1901 switch (atype) {
1902 case BGPTYPE_ORIGIN:
1903 if (len != 1)
1904 ND_PRINT("invalid len");
1905 else {
1906 ND_PRINT("%s", tok2str(bgp_origin_values,
1907 "Unknown Origin Typecode",
1908 GET_U_1(tptr)));
1909 }
1910 break;
1911
1912 /*
1913 * Process AS4 byte path and AS2 byte path attributes here.
1914 */
1915 case BGPTYPE_AS4_PATH:
1916 case BGPTYPE_AS_PATH:
1917 if (len % 2) {
1918 ND_PRINT("invalid len");
1919 break;
1920 }
1921 if (!len) {
1922 ND_PRINT("empty");
1923 break;
1924 }
1925
1926 /*
1927 * BGP updates exchanged between New speakers that support 4
1928 * byte AS, ASs are always encoded in 4 bytes. There is no
1929 * definitive way to find this, just by the packet's
1930 * contents. So, check for packet's TLV's sanity assuming
1931 * 2 bytes first, and it does not pass, assume that ASs are
1932 * encoded in 4 bytes format and move on.
1933 */
1934 as_size = bgp_attr_get_as_size(ndo, atype, pptr, len);
1935
1936 while (tptr < pptr + len) {
1937 ND_PRINT("%s", tok2str(bgp_as_path_segment_open_values,
1938 "?", GET_U_1(tptr)));
1939 for (i = 0; i < GET_U_1(tptr + 1) * as_size; i += as_size) {
1940 ND_TCHECK_LEN(tptr + 2 + i, as_size);
1941 ND_PRINT("%s ",
1942 as_printf(ndo, astostr, sizeof(astostr),
1943 as_size == 2 ?
1944 GET_BE_U_2(tptr + i + 2) :
1945 GET_BE_U_4(tptr + i + 2)));
1946 }
1947 ND_PRINT("%s", tok2str(bgp_as_path_segment_close_values,
1948 "?", GET_U_1(tptr)));
1949 tptr += 2 + GET_U_1(tptr + 1) * as_size;
1950 }
1951 break;
1952 case BGPTYPE_NEXT_HOP:
1953 if (len != 4)
1954 ND_PRINT("invalid len");
1955 else {
1956 ND_PRINT("%s", GET_IPADDR_STRING(tptr));
1957 }
1958 break;
1959 case BGPTYPE_MULTI_EXIT_DISC:
1960 case BGPTYPE_LOCAL_PREF:
1961 if (len != 4)
1962 ND_PRINT("invalid len");
1963 else {
1964 ND_PRINT("%u", GET_BE_U_4(tptr));
1965 }
1966 break;
1967 case BGPTYPE_ATOMIC_AGGREGATE:
1968 if (len != 0)
1969 ND_PRINT("invalid len");
1970 break;
1971 case BGPTYPE_AGGREGATOR:
1972
1973 /*
1974 * Depending on the AS encoded is of 2 bytes or of 4 bytes,
1975 * the length of this PA can be either 6 bytes or 8 bytes.
1976 */
1977 if (len != 6 && len != 8) {
1978 ND_PRINT("invalid len");
1979 break;
1980 }
1981 ND_TCHECK_LEN(tptr, len);
1982 if (len == 6) {
1983 ND_PRINT(" AS #%s, origin %s",
1984 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(tptr)),
1985 GET_IPADDR_STRING(tptr + 2));
1986 } else {
1987 ND_PRINT(" AS #%s, origin %s",
1988 as_printf(ndo, astostr, sizeof(astostr),
1989 GET_BE_U_4(tptr)), GET_IPADDR_STRING(tptr + 4));
1990 }
1991 break;
1992 case BGPTYPE_AGGREGATOR4:
1993 if (len != 8) {
1994 ND_PRINT("invalid len");
1995 break;
1996 }
1997 ND_PRINT(" AS #%s, origin %s",
1998 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)),
1999 GET_IPADDR_STRING(tptr + 4));
2000 break;
2001 case BGPTYPE_COMMUNITIES:
2002 if (len % 4) {
2003 ND_PRINT("invalid len");
2004 break;
2005 }
2006 while (tlen != 0) {
2007 uint32_t comm;
2008 ND_TCHECK_4(tptr);
2009 if (tlen < 4)
2010 goto trunc;
2011 comm = GET_BE_U_4(tptr);
2012 switch (comm) {
2013 case BGP_COMMUNITY_NO_EXPORT:
2014 ND_PRINT(" NO_EXPORT");
2015 break;
2016 case BGP_COMMUNITY_NO_ADVERT:
2017 ND_PRINT(" NO_ADVERTISE");
2018 break;
2019 case BGP_COMMUNITY_NO_EXPORT_SUBCONFED:
2020 ND_PRINT(" NO_EXPORT_SUBCONFED");
2021 break;
2022 default:
2023 ND_PRINT("%u:%u%s",
2024 (comm >> 16) & 0xffff,
2025 comm & 0xffff,
2026 (tlen>4) ? ", " : "");
2027 break;
2028 }
2029 tlen -=4;
2030 tptr +=4;
2031 }
2032 break;
2033 case BGPTYPE_ORIGINATOR_ID:
2034 if (len != 4) {
2035 ND_PRINT("invalid len");
2036 break;
2037 }
2038 ND_PRINT("%s",GET_IPADDR_STRING(tptr));
2039 break;
2040 case BGPTYPE_CLUSTER_LIST:
2041 if (len % 4) {
2042 ND_PRINT("invalid len");
2043 break;
2044 }
2045 while (tlen != 0) {
2046 if (tlen < 4)
2047 goto trunc;
2048 ND_PRINT("%s%s",
2049 GET_IPADDR_STRING(tptr),
2050 (tlen>4) ? ", " : "");
2051 tlen -=4;
2052 tptr +=4;
2053 }
2054 break;
2055 case BGPTYPE_MP_REACH_NLRI:
2056 ND_TCHECK_3(tptr);
2057 if (tlen < 3)
2058 goto trunc;
2059 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2060 if (ret == -2)
2061 goto trunc;
2062 if (ret < 0)
2063 break;
2064
2065 tptr += 3;
2066 tlen -= 3;
2067
2068 ND_TCHECK_1(tptr);
2069 if (tlen < 1)
2070 goto trunc;
2071 nhlen = GET_U_1(tptr);
2072 tptr++;
2073 tlen--;
2074
2075 if (nhlen) {
2076 u_int nnh = 0;
2077 uint8_t tnhlen = nhlen;
2078 if (tlen < tnhlen)
2079 goto trunc;
2080 ND_PRINT("\n\t nexthop: ");
2081 while (tnhlen != 0) {
2082 if (nnh++ > 0) {
2083 ND_PRINT(", " );
2084 }
2085 switch(af<<8 | safi) {
2086 case (AFNUM_INET<<8 | SAFNUM_UNICAST):
2087 case (AFNUM_INET<<8 | SAFNUM_MULTICAST):
2088 case (AFNUM_INET<<8 | SAFNUM_UNIMULTICAST):
2089 case (AFNUM_INET<<8 | SAFNUM_LABUNICAST):
2090 case (AFNUM_INET<<8 | SAFNUM_RT_ROUTING_INFO):
2091 case (AFNUM_INET<<8 | SAFNUM_MULTICAST_VPN):
2092 case (AFNUM_INET<<8 | SAFNUM_MDT):
2093 if (tnhlen < sizeof(nd_ipv4)) {
2094 ND_PRINT("invalid len");
2095 tptr += tnhlen;
2096 tlen -= tnhlen;
2097 tnhlen = 0;
2098 } else {
2099 ND_PRINT("%s",GET_IPADDR_STRING(tptr));
2100 tptr += sizeof(nd_ipv4);
2101 tnhlen -= sizeof(nd_ipv4);
2102 tlen -= sizeof(nd_ipv4);
2103 }
2104 break;
2105 case (AFNUM_INET<<8 | SAFNUM_VPNUNICAST):
2106 case (AFNUM_INET<<8 | SAFNUM_VPNMULTICAST):
2107 case (AFNUM_INET<<8 | SAFNUM_VPNUNIMULTICAST):
2108 if (tnhlen < sizeof(nd_ipv4)+BGP_VPN_RD_LEN) {
2109 ND_PRINT("invalid len");
2110 tptr += tnhlen;
2111 tlen -= tnhlen;
2112 tnhlen = 0;
2113 } else {
2114 ND_PRINT("RD: %s, %s",
2115 bgp_vpn_rd_print(ndo, tptr),
2116 GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN));
2117 tptr += (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2118 tlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2119 tnhlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN);
2120 }
2121 break;
2122 case (AFNUM_INET6<<8 | SAFNUM_UNICAST):
2123 case (AFNUM_INET6<<8 | SAFNUM_MULTICAST):
2124 case (AFNUM_INET6<<8 | SAFNUM_UNIMULTICAST):
2125 case (AFNUM_INET6<<8 | SAFNUM_LABUNICAST):
2126 if (tnhlen < sizeof(nd_ipv6)) {
2127 ND_PRINT("invalid len");
2128 tptr += tnhlen;
2129 tlen -= tnhlen;
2130 tnhlen = 0;
2131 } else {
2132 ND_PRINT("%s", GET_IP6ADDR_STRING(tptr));
2133 tptr += sizeof(nd_ipv6);
2134 tlen -= sizeof(nd_ipv6);
2135 tnhlen -= sizeof(nd_ipv6);
2136 }
2137 break;
2138 case (AFNUM_INET6<<8 | SAFNUM_VPNUNICAST):
2139 case (AFNUM_INET6<<8 | SAFNUM_VPNMULTICAST):
2140 case (AFNUM_INET6<<8 | SAFNUM_VPNUNIMULTICAST):
2141 if (tnhlen < sizeof(nd_ipv6)+BGP_VPN_RD_LEN) {
2142 ND_PRINT("invalid len");
2143 tptr += tnhlen;
2144 tlen -= tnhlen;
2145 tnhlen = 0;
2146 } else {
2147 ND_PRINT("RD: %s, %s",
2148 bgp_vpn_rd_print(ndo, tptr),
2149 GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN));
2150 tptr += (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2151 tlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2152 tnhlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN);
2153 }
2154 break;
2155 case (AFNUM_VPLS<<8 | SAFNUM_VPLS):
2156 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST):
2157 case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST):
2158 case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST):
2159 if (tnhlen < sizeof(nd_ipv4)) {
2160 ND_PRINT("invalid len");
2161 tptr += tnhlen;
2162 tlen -= tnhlen;
2163 tnhlen = 0;
2164 } else {
2165 ND_PRINT("%s", GET_IPADDR_STRING(tptr));
2166 tptr += (sizeof(nd_ipv4));
2167 tlen -= (sizeof(nd_ipv4));
2168 tnhlen -= (sizeof(nd_ipv4));
2169 }
2170 break;
2171 case (AFNUM_NSAP<<8 | SAFNUM_UNICAST):
2172 case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST):
2173 case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST):
2174 ND_PRINT("%s", GET_ISONSAP_STRING(tptr, tnhlen));
2175 tptr += tnhlen;
2176 tlen -= tnhlen;
2177 tnhlen = 0;
2178 break;
2179
2180 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST):
2181 case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST):
2182 case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST):
2183 if (tnhlen < BGP_VPN_RD_LEN+1) {
2184 ND_PRINT("invalid len");
2185 tptr += tnhlen;
2186 tlen -= tnhlen;
2187 tnhlen = 0;
2188 } else {
2189 ND_TCHECK_LEN(tptr, tnhlen);
2190 ND_PRINT("RD: %s, %s",
2191 bgp_vpn_rd_print(ndo, tptr),
2192 GET_ISONSAP_STRING(tptr+BGP_VPN_RD_LEN,tnhlen-BGP_VPN_RD_LEN));
2193 /* rfc986 mapped IPv4 address ? */
2194 if (GET_BE_U_4(tptr + BGP_VPN_RD_LEN) == 0x47000601)
2195 ND_PRINT(" = %s", GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN+4));
2196 /* rfc1888 mapped IPv6 address ? */
2197 else if (GET_BE_U_3(tptr + BGP_VPN_RD_LEN) == 0x350000)
2198 ND_PRINT(" = %s", GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN+3));
2199 tptr += tnhlen;
2200 tlen -= tnhlen;
2201 tnhlen = 0;
2202 }
2203 break;
2204 default:
2205 /*
2206 * bgp_mp_af_print() should have saved us from
2207 * an unsupported AFI/SAFI.
2208 */
2209 ND_PRINT("ERROR: no AFI %u/SAFI %u nexthop decoder", af, safi);
2210 tptr += tnhlen;
2211 tlen -= tnhlen;
2212 tnhlen = 0;
2213 goto done;
2214 break;
2215 }
2216 }
2217 }
2218 ND_PRINT(", nh-length: %u", nhlen);
2219
2220 /* As per RFC 2858; this is reserved in RFC 4760 */
2221 if (tlen < 1)
2222 goto trunc;
2223 snpa = GET_U_1(tptr);
2224 tptr++;
2225 tlen--;
2226
2227 if (snpa) {
2228 ND_PRINT("\n\t %u SNPA", snpa);
2229 for (/*nothing*/; snpa != 0; snpa--) {
2230 uint8_t snpalen;
2231 if (tlen < 1)
2232 goto trunc;
2233 snpalen = GET_U_1(tptr);
2234 ND_PRINT("\n\t %u bytes", snpalen);
2235 tptr++;
2236 tlen--;
2237 if (tlen < snpalen)
2238 goto trunc;
2239 ND_TCHECK_LEN(tptr, snpalen);
2240 tptr += snpalen;
2241 tlen -= snpalen;
2242 }
2243 } else {
2244 ND_PRINT(", no SNPA");
2245 }
2246
2247 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2248 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2249
2250 while (tptr < pptr + len) {
2251 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2252 add_path4, add_path6);
2253 if (advance == -2)
2254 goto trunc;
2255 if (advance < 0)
2256 break;
2257 tptr += advance;
2258 }
2259 break;
2260
2261 case BGPTYPE_MP_UNREACH_NLRI:
2262 ND_TCHECK_LEN(tptr, BGP_MP_NLRI_MINSIZE);
2263 ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi);
2264 if (ret == -2)
2265 goto trunc;
2266 if (ret < 0)
2267 break;
2268
2269 if (len == BGP_MP_NLRI_MINSIZE)
2270 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2271
2272 tptr += 3;
2273
2274 add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32);
2275 add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128);
2276
2277 while (tptr < pptr + len) {
2278 advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf),
2279 add_path4, add_path6);
2280 if (advance == -2)
2281 goto trunc;
2282 if (advance < 0)
2283 break;
2284 tptr += advance;
2285 }
2286 break;
2287 case BGPTYPE_EXTD_COMMUNITIES:
2288 if (len % 8) {
2289 ND_PRINT("invalid len");
2290 break;
2291 }
2292 while (tlen != 0) {
2293 uint16_t extd_comm;
2294
2295 ND_TCHECK_2(tptr);
2296 if (tlen < 2)
2297 goto trunc;
2298 extd_comm=GET_BE_U_2(tptr);
2299
2300 ND_PRINT("\n\t %s (0x%04x), Flags [%s]",
2301 tok2str(bgp_extd_comm_subtype_values,
2302 "unknown extd community typecode",
2303 extd_comm),
2304 extd_comm,
2305 bittok2str(bgp_extd_comm_flag_values, "none", extd_comm));
2306
2307 ND_TCHECK_8(tptr);
2308 if (tlen < 8)
2309 goto trunc;
2310 ND_PRINT(": ");
2311 bgp_extended_community_print(ndo, tptr);
2312 tlen -= 8;
2313 tptr += 8;
2314 }
2315 break;
2316
2317 case BGPTYPE_PMSI_TUNNEL:
2318 {
2319 uint8_t tunnel_type, flags;
2320
2321 ND_TCHECK_5(tptr);
2322 if (tlen < 5)
2323 goto trunc;
2324 flags = GET_U_1(tptr);
2325 tunnel_type = GET_U_1(tptr + 1);
2326
2327 ND_PRINT("\n\t Tunnel-type %s (%u), Flags [%s], MPLS Label %u",
2328 tok2str(bgp_pmsi_tunnel_values, "Unknown", tunnel_type),
2329 tunnel_type,
2330 bittok2str(bgp_pmsi_flag_values, "none", flags),
2331 GET_BE_U_3(tptr + 2)>>4);
2332
2333 tptr +=5;
2334 tlen -= 5;
2335
2336 switch (tunnel_type) {
2337 case BGP_PMSI_TUNNEL_PIM_SM: /* fall through */
2338 case BGP_PMSI_TUNNEL_PIM_BIDIR:
2339 ND_PRINT("\n\t Sender %s, P-Group %s",
2340 GET_IPADDR_STRING(tptr),
2341 GET_IPADDR_STRING(tptr+4));
2342 break;
2343
2344 case BGP_PMSI_TUNNEL_PIM_SSM:
2345 ND_PRINT("\n\t Root-Node %s, P-Group %s",
2346 GET_IPADDR_STRING(tptr),
2347 GET_IPADDR_STRING(tptr+4));
2348 break;
2349 case BGP_PMSI_TUNNEL_INGRESS:
2350 ND_PRINT("\n\t Tunnel-Endpoint %s",
2351 GET_IPADDR_STRING(tptr));
2352 break;
2353 case BGP_PMSI_TUNNEL_LDP_P2MP: /* fall through */
2354 case BGP_PMSI_TUNNEL_LDP_MP2MP:
2355 ND_PRINT("\n\t Root-Node %s, LSP-ID 0x%08x",
2356 GET_IPADDR_STRING(tptr),
2357 GET_BE_U_4(tptr + 4));
2358 break;
2359 case BGP_PMSI_TUNNEL_RSVP_P2MP:
2360 ND_PRINT("\n\t Extended-Tunnel-ID %s, P2MP-ID 0x%08x",
2361 GET_IPADDR_STRING(tptr),
2362 GET_BE_U_4(tptr + 4));
2363 break;
2364 default:
2365 if (ndo->ndo_vflag <= 1) {
2366 print_unknown_data(ndo, tptr, "\n\t ", tlen);
2367 }
2368 }
2369 break;
2370 }
2371 case BGPTYPE_AIGP:
2372 {
2373 uint8_t type;
2374 uint16_t length;
2375
2376 while (tlen >= 3) {
2377 type = GET_U_1(tptr);
2378 length = GET_BE_U_2(tptr + 1);
2379 tptr += 3;
2380 tlen -= 3;
2381
2382 ND_PRINT("\n\t %s TLV (%u), length %u",
2383 tok2str(bgp_aigp_values, "Unknown", type),
2384 type, length);
2385
2386 if (length < 3)
2387 goto trunc;
2388 length -= 3;
2389
2390 /*
2391 * Check if we can read the TLV data.
2392 */
2393 if (tlen < length)
2394 goto trunc;
2395
2396 switch (type) {
2397
2398 case BGP_AIGP_TLV:
2399 if (length < 8)
2400 goto trunc;
2401 ND_PRINT(", metric %" PRIu64,
2402 GET_BE_U_8(tptr));
2403 break;
2404
2405 default:
2406 if (ndo->ndo_vflag <= 1) {
2407 print_unknown_data(ndo, tptr,"\n\t ", length);
2408 }
2409 }
2410
2411 tptr += length;
2412 tlen -= length;
2413 }
2414 break;
2415 }
2416 case BGPTYPE_ATTR_SET:
2417 ND_TCHECK_4(tptr);
2418 if (len < 4)
2419 goto trunc;
2420 ND_PRINT("\n\t Origin AS: %s",
2421 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)));
2422 tptr += 4;
2423 len -= 4;
2424
2425 while (len) {
2426 u_int aflags, alenlen, alen;
2427
2428 ND_TCHECK_2(tptr);
2429 if (len < 2) {
2430 ND_PRINT(" [path attr too short]");
2431 tptr += len;
2432 break;
2433 }
2434 aflags = GET_U_1(tptr);
2435 atype = GET_U_1(tptr + 1);
2436 tptr += 2;
2437 len -= 2;
2438 alenlen = bgp_attr_lenlen(aflags, tptr);
2439 ND_TCHECK_LEN(tptr, alenlen);
2440 if (len < alenlen) {
2441 ND_PRINT(" [path attr too short]");
2442 tptr += len;
2443 break;
2444 }
2445 alen = bgp_attr_len(aflags, tptr);
2446 tptr += alenlen;
2447 len -= alenlen;
2448
2449 ND_PRINT("\n\t %s (%u), length: %u",
2450 tok2str(bgp_attr_values,
2451 "Unknown Attribute", atype),
2452 atype,
2453 alen);
2454
2455 if (aflags) {
2456 ND_PRINT(", Flags [%s%s%s%s",
2457 aflags & 0x80 ? "O" : "",
2458 aflags & 0x40 ? "T" : "",
2459 aflags & 0x20 ? "P" : "",
2460 aflags & 0x10 ? "E" : "");
2461 if (aflags & 0xf)
2462 ND_PRINT("+%x", aflags & 0xf);
2463 ND_PRINT("]");
2464 }
2465 ND_PRINT(": ");
2466 if (len < alen) {
2467 ND_PRINT(" [path attr too short]");
2468 tptr += len;
2469 break;
2470 }
2471 /*
2472 * The protocol encoding per se allows ATTR_SET to be nested
2473 * as many times as the message can accommodate. This printer
2474 * used to be able to recurse into ATTR_SET contents until the
2475 * stack exhaustion, but now there is a limit on that (if live
2476 * protocol exchange goes that many levels deep, something is
2477 * probably wrong anyway). Feel free to refine this value if
2478 * you can find the spec with respective normative text.
2479 */
2480 if (attr_set_level == 10)
2481 ND_PRINT("(too many nested levels, not recursing)");
2482 else if (!bgp_attr_print(ndo, atype, tptr, alen, attr_set_level + 1))
2483 return 0;
2484 tptr += alen;
2485 len -= alen;
2486 }
2487 break;
2488
2489 case BGPTYPE_LARGE_COMMUNITY:
2490 if (len == 0 || len % 12) {
2491 ND_PRINT("invalid len");
2492 break;
2493 }
2494 ND_PRINT("\n\t ");
2495 while (len != 0) {
2496 ND_PRINT("%u:%u:%u%s",
2497 GET_BE_U_4(tptr),
2498 GET_BE_U_4(tptr + 4),
2499 GET_BE_U_4(tptr + 8),
2500 (len > 12) ? ", " : "");
2501 tptr += 12;
2502 /*
2503 * len will always be a multiple of 12, as per the above,
2504 * so this will never underflow.
2505 */
2506 len -= 12;
2507 }
2508 break;
2509 default:
2510 ND_TCHECK_LEN(pptr, len);
2511 ND_PRINT("\n\t no Attribute %u decoder", atype); /* we have no decoder for the attribute */
2512 if (ndo->ndo_vflag <= 1)
2513 print_unknown_data(ndo, pptr, "\n\t ", len);
2514 break;
2515 }
2516 done:
2517 if (ndo->ndo_vflag > 1 && len) { /* omit zero length attributes*/
2518 ND_TCHECK_LEN(pptr, len);
2519 print_unknown_data(ndo, pptr, "\n\t ", len);
2520 }
2521 return 1;
2522
2523 trunc:
2524 return 0;
2525 }
2526
2527 static void
2528 bgp_capabilities_print(netdissect_options *ndo,
2529 const u_char *opt, u_int caps_len)
2530 {
2531 /* allocate space for the largest possible string */
2532 char astostr[AS_STR_SIZE];
2533 u_int cap_type, cap_len, tcap_len, cap_offset;
2534 u_int i = 0;
2535
2536 while (i < caps_len) {
2537 ND_TCHECK_LEN(opt + i, BGP_CAP_HEADER_SIZE);
2538 cap_type=GET_U_1(opt + i);
2539 cap_len=GET_U_1(opt + i + 1);
2540 ND_PRINT("\n\t %s (%u), length: %u",
2541 tok2str(bgp_capcode_values, "Unknown", cap_type),
2542 cap_type,
2543 cap_len);
2544 ND_TCHECK_LEN(opt + 2 + i, cap_len);
2545 switch (cap_type) {
2546 case BGP_CAPCODE_MP:
2547 /* AFI (16 bits), Reserved (8 bits), SAFI (8 bits) */
2548 if (cap_len < 4) {
2549 ND_PRINT(" (too short, < 4)");
2550 return;
2551 }
2552 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u)",
2553 tok2str(af_values, "Unknown", GET_BE_U_2(opt + i + 2)),
2554 GET_BE_U_2(opt + i + 2),
2555 tok2str(bgp_safi_values, "Unknown", GET_U_1(opt + i + 5)),
2556 GET_U_1(opt + i + 5));
2557 break;
2558 case BGP_CAPCODE_ML:
2559 cap_offset = 2;
2560 tcap_len = cap_len;
2561 while (tcap_len >= 4) {
2562 ND_PRINT( "\n\t\tAFI %s (%u), SAFI %s (%u), Count: %u",
2563 tok2str(af_values, "Unknown",
2564 GET_BE_U_2(opt + i + cap_offset)),
2565 GET_BE_U_2(opt + i + cap_offset),
2566 tok2str(bgp_safi_values, "Unknown",
2567 GET_U_1(opt + i + cap_offset + 2)),
2568 GET_U_1(opt + i + cap_offset + 2),
2569 GET_U_1(opt + i + cap_offset + 3));
2570 tcap_len -= 4;
2571 cap_offset += 4;
2572 }
2573 break;
2574 case BGP_CAPCODE_RESTART:
2575 /* Restart Flags (4 bits), Restart Time in seconds (12 bits) */
2576 if (cap_len < 2) {
2577 ND_PRINT(" (too short, < 2)");
2578 return;
2579 }
2580 tcap_len=cap_len;
2581 ND_PRINT("\n\t\tRestart Flags: [%s], Restart Time %us",
2582 ((GET_U_1(opt + i + 2))&0x80) ? "R" : "none",
2583 GET_BE_U_2(opt + i + 2)&0xfff);
2584 tcap_len-=2;
2585 cap_offset=4;
2586 while(tcap_len>=4) {
2587 ND_PRINT("\n\t\t AFI %s (%u), SAFI %s (%u), Forwarding state preserved: %s",
2588 tok2str(af_values,"Unknown",
2589 GET_BE_U_2(opt + i + cap_offset)),
2590 GET_BE_U_2(opt + i + cap_offset),
2591 tok2str(bgp_safi_values,"Unknown",
2592 GET_U_1(opt + i + cap_offset + 2)),
2593 GET_U_1(opt + (i + cap_offset + 2)),
2594 ((GET_U_1(opt + (i + cap_offset + 3)))&0x80) ? "yes" : "no" );
2595 tcap_len -= 4;
2596 cap_offset += 4;
2597 }
2598 break;
2599 case BGP_CAPCODE_RR:
2600 case BGP_CAPCODE_LLGR:
2601 case BGP_CAPCODE_RR_CISCO:
2602 case BGP_CAPCODE_EXT_MSG:
2603 case BGP_CAPCODE_ENH_RR:
2604 break;
2605 case BGP_CAPCODE_AS_NEW:
2606 /*
2607 * Extract the 4 byte AS number encoded.
2608 */
2609 if (cap_len < 4) {
2610 ND_PRINT(" (too short, < 4)");
2611 return;
2612 }
2613 ND_PRINT("\n\t\t 4 Byte AS %s",
2614 as_printf(ndo, astostr, sizeof(astostr),
2615 GET_BE_U_4(opt + i + 2)));
2616 break;
2617 case BGP_CAPCODE_ADD_PATH:
2618 if (cap_len == 0) {
2619 ND_PRINT(" (bogus)"); /* length */
2620 break;
2621 }
2622 tcap_len=cap_len;
2623 cap_offset=2;
2624 while (tcap_len != 0) {
2625 if (tcap_len < 4) {
2626 nd_print_invalid(ndo);
2627 break;
2628 }
2629 ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u), Send/Receive: %s",
2630 tok2str(af_values,"Unknown",GET_BE_U_2(opt + i + cap_offset)),
2631 GET_BE_U_2(opt + i + cap_offset),
2632 tok2str(bgp_safi_values,"Unknown",GET_U_1(opt + i + cap_offset + 2)),
2633 GET_U_1(opt + (i + cap_offset + 2)),
2634 tok2str(bgp_add_path_recvsend,"Bogus (0x%02x)",GET_U_1(opt + i + cap_offset + 3))
2635 );
2636 tcap_len -= 4;
2637 cap_offset += 4;
2638 }
2639 break;
2640 default:
2641 ND_PRINT("\n\t\tno decoder for Capability %u",
2642 cap_type);
2643 if (ndo->ndo_vflag <= 1)
2644 print_unknown_data(ndo, opt + i + 2, "\n\t\t",
2645 cap_len);
2646 break;
2647 }
2648 if (ndo->ndo_vflag > 1 && cap_len != 0) {
2649 print_unknown_data(ndo, opt + i + 2, "\n\t\t", cap_len);
2650 }
2651 i += BGP_CAP_HEADER_SIZE + cap_len;
2652 }
2653 return;
2654
2655 trunc:
2656 nd_print_trunc(ndo);
2657 }
2658
2659 static void
2660 bgp_open_print(netdissect_options *ndo,
2661 const u_char *dat, u_int length)
2662 {
2663 /* allocate space for the largest possible string */
2664 char astostr[AS_STR_SIZE];
2665 const struct bgp_open *bgp_open_header;
2666 u_int optslen;
2667 uint8_t opsttype;
2668 const struct bgp_opt *bgpopt;
2669 const u_char *opt;
2670 u_int i;
2671 uint8_t extended_opt_params = 0;
2672 u_int open_size = BGP_OPEN_SIZE;
2673 u_int opt_size = BGP_OPT_SIZE;
2674
2675 ND_TCHECK_LEN(dat, BGP_OPEN_SIZE);
2676 if (length < BGP_OPEN_SIZE)
2677 goto trunc;
2678
2679 bgp_open_header = (const struct bgp_open *)dat;
2680
2681 ND_PRINT("\n\t Version %u, ",
2682 GET_U_1(bgp_open_header->bgpo_version));
2683 ND_PRINT("my AS %s, ",
2684 as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(bgp_open_header->bgpo_myas)));
2685 ND_PRINT("Holdtime %us, ",
2686 GET_BE_U_2(bgp_open_header->bgpo_holdtime));
2687 ND_PRINT("ID %s", GET_IPADDR_STRING(bgp_open_header->bgpo_id));
2688 optslen = GET_U_1(bgp_open_header->bgpo_optlen);
2689 opsttype = GET_U_1(bgp_open_header->bgpo_opttype);
2690 if (opsttype == BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH) {
2691 optslen = GET_BE_U_2(bgp_open_header->bgpo_optlen_extended);
2692 extended_opt_params = 1;
2693 open_size += 3;
2694 opt_size += 1;
2695 }
2696 ND_PRINT("\n\t Optional parameters%s, length: %u",
2697 extended_opt_params ? " (Extended)" : "", optslen);
2698
2699 opt = dat + open_size;
2700 length -= open_size;
2701
2702 i = 0;
2703 while (i < optslen) {
2704 uint8_t opt_type;
2705 uint16_t opt_len;
2706
2707 ND_TCHECK_LEN(opt + i, opt_size);
2708 if (length < opt_size + i)
2709 goto trunc;
2710 bgpopt = (const struct bgp_opt *)(opt + i);
2711 opt_type = GET_U_1(bgpopt->bgpopt_type);
2712 opt_len = extended_opt_params ? GET_BE_U_2(bgpopt->bgpopt_len)
2713 : GET_U_1(bgpopt->bgpopt_len);
2714 if (opt_size + i + opt_len > optslen) {
2715 ND_PRINT("\n\t Option %u, length: %u, goes past the end of the options",
2716 opt_type, opt_len);
2717 break;
2718 }
2719
2720 ND_PRINT("\n\t Option %s (%u), length: %u",
2721 tok2str(bgp_opt_values,"Unknown",opt_type),
2722 opt_type,
2723 opt_len);
2724
2725 /* now let's decode the options we know*/
2726 switch(opt_type) {
2727
2728 case BGP_OPT_CAP:
2729 bgp_capabilities_print(ndo, opt + opt_size + i,
2730 opt_len);
2731 break;
2732
2733 case BGP_OPT_AUTH:
2734 default:
2735 ND_PRINT("\n\t no decoder for option %u",
2736 opt_type);
2737 break;
2738 }
2739 i += opt_size + opt_len;
2740 }
2741 return;
2742 trunc:
2743 nd_print_trunc(ndo);
2744 }
2745
2746 static void
2747 bgp_update_print(netdissect_options *ndo,
2748 const u_char *dat, u_int length)
2749 {
2750 const u_char *p;
2751 u_int withdrawn_routes_len;
2752 char buf[MAXHOSTNAMELEN + 100];
2753 int wpfx;
2754 u_int len;
2755 int i;
2756 int add_path;
2757 u_int path_id = 0;
2758
2759 ND_TCHECK_LEN(dat, BGP_SIZE);
2760 if (length < BGP_SIZE)
2761 goto trunc;
2762 p = dat + BGP_SIZE;
2763 length -= BGP_SIZE;
2764
2765 /* Unfeasible routes */
2766 ND_TCHECK_2(p);
2767 if (length < 2)
2768 goto trunc;
2769 withdrawn_routes_len = GET_BE_U_2(p);
2770 p += 2;
2771 length -= 2;
2772 if (withdrawn_routes_len > 1) {
2773 /*
2774 * Without keeping state from the original NLRI message,
2775 * it's not possible to tell if this a v4 or v6 route,
2776 * so only try to decode it if we're not v6 enabled.
2777 */
2778 ND_TCHECK_LEN(p, withdrawn_routes_len);
2779 if (length < withdrawn_routes_len)
2780 goto trunc;
2781 ND_PRINT("\n\t Withdrawn routes:");
2782 add_path = check_add_path(ndo, p, withdrawn_routes_len, 32);
2783 while (withdrawn_routes_len != 0) {
2784 if (add_path) {
2785 if (withdrawn_routes_len < 4) {
2786 p += withdrawn_routes_len;
2787 length -= withdrawn_routes_len;
2788 break;
2789 }
2790 path_id = GET_BE_U_4(p);
2791 p += 4;
2792 length -= 4;
2793 withdrawn_routes_len -= 4;
2794 }
2795 wpfx = decode_prefix4(ndo, p, withdrawn_routes_len, buf, sizeof(buf));
2796 if (wpfx == -1) {
2797 ND_PRINT("\n\t (illegal prefix length)");
2798 break;
2799 } else if (wpfx == -2)
2800 goto trunc; /* bytes left, but not enough */
2801 else {
2802 ND_PRINT("\n\t %s", buf);
2803 if (add_path) {
2804 ND_PRINT(" Path Id: %u", path_id);
2805 }
2806 p += wpfx;
2807 length -= wpfx;
2808 withdrawn_routes_len -= wpfx;
2809 }
2810 }
2811 } else {
2812 ND_TCHECK_LEN(p, withdrawn_routes_len);
2813 if (length < withdrawn_routes_len)
2814 goto trunc;
2815 p += withdrawn_routes_len;
2816 length -= withdrawn_routes_len;
2817 }
2818
2819 ND_TCHECK_2(p);
2820 if (length < 2)
2821 goto trunc;
2822 len = GET_BE_U_2(p);
2823 p += 2;
2824 length -= 2;
2825
2826 if (withdrawn_routes_len == 0 && len == 0 && length == 0) {
2827 /* No withdrawn routes, no path attributes, no NLRI */
2828 ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)");
2829 return;
2830 }
2831
2832 if (len) {
2833 /* Make sure the path attributes don't go past the end of the packet */
2834 if (length < len)
2835 goto trunc;
2836 /* do something more useful!*/
2837 while (len) {
2838 uint8_t aflags, atype, alenlen;
2839 uint16_t alen;
2840
2841 ND_TCHECK_2(p);
2842 if (length < 2)
2843 goto trunc;
2844 if (len < 2) {
2845 ND_PRINT("\n\t [path attrs too short]");
2846 p += len;
2847 length -= len;
2848 break;
2849 }
2850 aflags = GET_U_1(p);
2851 atype = GET_U_1(p + 1);
2852 p += 2;
2853 len -= 2;
2854 length -= 2;
2855 alenlen = bgp_attr_lenlen(aflags, p);
2856 ND_TCHECK_LEN(p, alenlen);
2857 if (length < alenlen)
2858 goto trunc;
2859 if (len < alenlen) {
2860 ND_PRINT("\n\t [path attrs too short]");
2861 p += len;
2862 length -= len;
2863 break;
2864 }
2865 alen = bgp_attr_len(aflags, p);
2866 p += alenlen;
2867 len -= alenlen;
2868 length -= alenlen;
2869
2870 ND_PRINT("\n\t %s (%u), length: %u",
2871 tok2str(bgp_attr_values, "Unknown Attribute", atype),
2872 atype,
2873 alen);
2874
2875 if (aflags) {
2876 ND_PRINT(", Flags [%s%s%s%s",
2877 aflags & 0x80 ? "O" : "",
2878 aflags & 0x40 ? "T" : "",
2879 aflags & 0x20 ? "P" : "",
2880 aflags & 0x10 ? "E" : "");
2881 if (aflags & 0xf)
2882 ND_PRINT("+%x", aflags & 0xf);
2883 ND_PRINT("]: ");
2884 }
2885 if (len < alen) {
2886 ND_PRINT(" [path attrs too short]");
2887 p += len;
2888 length -= len;
2889 break;
2890 }
2891 if (length < alen)
2892 goto trunc;
2893 if (!bgp_attr_print(ndo, atype, p, alen, 0))
2894 goto trunc;
2895 p += alen;
2896 len -= alen;
2897 length -= alen;
2898 }
2899 }
2900
2901 if (length) {
2902 add_path = check_add_path(ndo, p, length, 32);
2903 ND_PRINT("\n\t Updated routes:");
2904 while (length != 0) {
2905 if (add_path) {
2906 ND_TCHECK_4(p);
2907 if (length < 4)
2908 goto trunc;
2909 path_id = GET_BE_U_4(p);
2910 p += 4;
2911 length -= 4;
2912 }
2913 i = decode_prefix4(ndo, p, length, buf, sizeof(buf));
2914 if (i == -1) {
2915 ND_PRINT("\n\t (illegal prefix length)");
2916 break;
2917 } else if (i == -2)
2918 goto trunc; /* bytes left, but not enough */
2919 else {
2920 ND_PRINT("\n\t %s", buf);
2921 if (add_path) {
2922 ND_PRINT(" Path Id: %u", path_id);
2923 }
2924 p += i;
2925 length -= i;
2926 }
2927 }
2928 }
2929 return;
2930 trunc:
2931 nd_print_trunc(ndo);
2932 }
2933
2934 static void
2935 bgp_notification_print(netdissect_options *ndo,
2936 const u_char *dat, u_int length)
2937 {
2938 const struct bgp_notification *bgp_notification_header;
2939 const u_char *tptr;
2940 uint8_t bgpn_major, bgpn_minor;
2941
2942 ND_TCHECK_LEN(dat, BGP_NOTIFICATION_SIZE);
2943 if (length<BGP_NOTIFICATION_SIZE)
2944 return;
2945
2946 bgp_notification_header = (const struct bgp_notification *)dat;
2947 bgpn_major = GET_U_1(bgp_notification_header->bgpn_major);
2948 bgpn_minor = GET_U_1(bgp_notification_header->bgpn_minor);
2949
2950 ND_PRINT(", %s (%u)",
2951 tok2str(bgp_notify_major_values, "Unknown Error",
2952 bgpn_major),
2953 bgpn_major);
2954
2955 switch (bgpn_major) {
2956
2957 case BGP_NOTIFY_MAJOR_MSG:
2958 ND_PRINT(", subcode %s (%u)",
2959 tok2str(bgp_notify_minor_msg_values, "Unknown",
2960 bgpn_minor),
2961 bgpn_minor);
2962 break;
2963 case BGP_NOTIFY_MAJOR_OPEN:
2964 ND_PRINT(", subcode %s (%u)",
2965 tok2str(bgp_notify_minor_open_values, "Unknown",
2966 bgpn_minor),
2967 bgpn_minor);
2968 break;
2969 case BGP_NOTIFY_MAJOR_UPDATE:
2970 ND_PRINT(", subcode %s (%u)",
2971 tok2str(bgp_notify_minor_update_values, "Unknown",
2972 bgpn_minor),
2973 bgpn_minor);
2974 break;
2975 case BGP_NOTIFY_MAJOR_FSM:
2976 ND_PRINT(" subcode %s (%u)",
2977 tok2str(bgp_notify_minor_fsm_values, "Unknown",
2978 bgpn_minor),
2979 bgpn_minor);
2980 break;
2981 case BGP_NOTIFY_MAJOR_CAP:
2982 ND_PRINT(" subcode %s (%u)",
2983 tok2str(bgp_notify_minor_cap_values, "Unknown",
2984 bgpn_minor),
2985 bgpn_minor);
2986 break;
2987 case BGP_NOTIFY_MAJOR_CEASE:
2988 ND_PRINT(", subcode %s (%u)",
2989 tok2str(bgp_notify_minor_cease_values, "Unknown",
2990 bgpn_minor),
2991 bgpn_minor);
2992
2993 /* RFC 4486 mentions optionally 7 bytes
2994 * for the maxprefix subtype, which may contain AFI, SAFI and MAXPREFIXES
2995 */
2996 if(bgpn_minor == BGP_NOTIFY_MINOR_CEASE_MAXPRFX && length >= BGP_NOTIFICATION_SIZE + 7) {
2997 tptr = dat + BGP_NOTIFICATION_SIZE;
2998 ND_PRINT(", AFI %s (%u), SAFI %s (%u), Max Prefixes: %u",
2999 tok2str(af_values, "Unknown", GET_BE_U_2(tptr)),
3000 GET_BE_U_2(tptr),
3001 tok2str(bgp_safi_values, "Unknown", GET_U_1((tptr + 2))),
3002 GET_U_1((tptr + 2)),
3003 GET_BE_U_4(tptr + 3));
3004 }
3005 /*
3006 * RFC 9003 describes a method to send a communication
3007 * intended for human consumption regarding the Administrative Shutdown
3008 */
3009 if ((bgpn_minor == BGP_NOTIFY_MINOR_CEASE_SHUT ||
3010 bgpn_minor == BGP_NOTIFY_MINOR_CEASE_RESET) &&
3011 length >= BGP_NOTIFICATION_SIZE + 1) {
3012 tptr = dat + BGP_NOTIFICATION_SIZE;
3013 uint8_t shutdown_comm_length = GET_U_1(tptr);
3014 uint8_t remainder_offset = 0;
3015 /* garbage, hexdump it all */
3016 if (shutdown_comm_length > length - (BGP_NOTIFICATION_SIZE + 1)) {
3017 ND_PRINT(", invalid Shutdown Communication length");
3018 }
3019 else if (shutdown_comm_length == 0) {
3020 ND_PRINT(", empty Shutdown Communication");
3021 remainder_offset += 1;
3022 }
3023 /* a proper shutdown communication */
3024 else {
3025 ND_PRINT(", Shutdown Communication (length: %u): \"", shutdown_comm_length);
3026 nd_printjn(ndo, tptr+1, shutdown_comm_length);
3027 ND_PRINT("\"");
3028 remainder_offset += shutdown_comm_length + 1;
3029 }
3030 /* if there is trailing data, hexdump it */
3031 if(length - (remainder_offset + BGP_NOTIFICATION_SIZE) > 0) {
3032 ND_PRINT(", Data: (length: %u)", length - (remainder_offset + BGP_NOTIFICATION_SIZE));
3033 hex_print(ndo, "\n\t\t", tptr + remainder_offset, length - (remainder_offset + BGP_NOTIFICATION_SIZE));
3034 }
3035 }
3036 break;
3037 default:
3038 break;
3039 }
3040
3041 return;
3042 trunc:
3043 nd_print_trunc(ndo);
3044 }
3045
3046 static void
3047 bgp_route_refresh_print(netdissect_options *ndo,
3048 const u_char *pptr, u_int len)
3049 {
3050 const struct bgp_route_refresh *bgp_route_refresh_header;
3051
3052 ND_TCHECK_LEN(pptr, BGP_ROUTE_REFRESH_SIZE);
3053
3054 /* some little sanity checking */
3055 if (len<BGP_ROUTE_REFRESH_SIZE)
3056 return;
3057
3058 bgp_route_refresh_header = (const struct bgp_route_refresh *)pptr;
3059
3060 ND_PRINT("\n\t AFI %s (%u), SAFI %s (%u), Subtype %s (%u)",
3061 tok2str(af_values, "Unknown",
3062 GET_BE_U_2(bgp_route_refresh_header->afi)),
3063 GET_BE_U_2(bgp_route_refresh_header->afi),
3064 tok2str(bgp_safi_values, "Unknown",
3065 GET_U_1(bgp_route_refresh_header->safi)),
3066 GET_U_1(bgp_route_refresh_header->safi),
3067 tok2str(bgp_route_refresh_subtype_values, "Unknown",
3068 GET_U_1(bgp_route_refresh_header->subtype)),
3069 GET_U_1(bgp_route_refresh_header->subtype));
3070
3071 if (ndo->ndo_vflag > 1) {
3072 ND_TCHECK_LEN(pptr, len);
3073 print_unknown_data(ndo, pptr, "\n\t ", len);
3074 }
3075
3076 return;
3077 trunc:
3078 nd_print_trunc(ndo);
3079 }
3080
3081 static int
3082 bgp_pdu_print(netdissect_options *ndo,
3083 const u_char *dat, u_int length)
3084 {
3085 const struct bgp *bgp_header;
3086 uint8_t bgp_type;
3087
3088 ND_TCHECK_LEN(dat, BGP_SIZE);
3089 bgp_header = (const struct bgp *)dat;
3090 bgp_type = GET_U_1(bgp_header->bgp_type);
3091
3092 ND_PRINT("\n\t%s Message (%u), length: %u",
3093 tok2str(bgp_msg_values, "Unknown", bgp_type),
3094 bgp_type,
3095 length);
3096
3097 switch (bgp_type) {
3098 case BGP_OPEN:
3099 bgp_open_print(ndo, dat, length);
3100 break;
3101 case BGP_UPDATE:
3102 bgp_update_print(ndo, dat, length);
3103 break;
3104 case BGP_NOTIFICATION:
3105 bgp_notification_print(ndo, dat, length);
3106 break;
3107 case BGP_KEEPALIVE:
3108 break;
3109 case BGP_ROUTE_REFRESH:
3110 bgp_route_refresh_print(ndo, dat, length);
3111 break;
3112 default:
3113 /* we have no decoder for the BGP message */
3114 ND_TCHECK_LEN(dat, length);
3115 ND_PRINT("\n\t no Message %u decoder", bgp_type);
3116 print_unknown_data(ndo, dat, "\n\t ", length);
3117 break;
3118 }
3119 return 1;
3120 trunc:
3121 nd_print_trunc(ndo);
3122 return 0;
3123 }
3124
3125 void
3126 bgp_print(netdissect_options *ndo,
3127 const u_char *dat, u_int length _U_)
3128 {
3129 const u_char *p;
3130 const u_char *ep = ndo->ndo_snapend;
3131 const u_char *start;
3132 const u_char marker[] = {
3133 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3134 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
3135 };
3136 const struct bgp *bgp_header;
3137 uint16_t hlen;
3138
3139 ndo->ndo_protocol = "bgp";
3140 ND_PRINT(": BGP");
3141
3142 if (ndo->ndo_vflag < 1) /* lets be less chatty */
3143 return;
3144
3145 p = dat;
3146 start = p;
3147 while (p < ep) {
3148 if (!ND_TTEST_1(p))
3149 break;
3150 if (GET_U_1(p) != 0xff) {
3151 p++;
3152 continue;
3153 }
3154
3155 if (!ND_TTEST_LEN(p, sizeof(marker)))
3156 break;
3157 if (memcmp(p, marker, sizeof(marker)) != 0) {
3158 p++;
3159 continue;
3160 }
3161
3162 /* found BGP header */
3163 ND_TCHECK_LEN(p, BGP_SIZE);
3164 bgp_header = (const struct bgp *)p;
3165
3166 if (start != p)
3167 nd_print_trunc(ndo);
3168
3169 hlen = GET_BE_U_2(bgp_header->bgp_len);
3170 if (hlen < BGP_SIZE) {
3171 ND_PRINT("\nmessage length %u < %u", hlen, BGP_SIZE);
3172 nd_print_invalid(ndo);
3173 break;
3174 }
3175
3176 if (ND_TTEST_LEN(p, hlen)) {
3177 if (!bgp_pdu_print(ndo, p, hlen))
3178 return;
3179 p += hlen;
3180 start = p;
3181 } else {
3182 ND_PRINT("\n[|BGP %s]",
3183 tok2str(bgp_msg_values,
3184 "Unknown Message Type",
3185 GET_U_1(bgp_header->bgp_type)));
3186 break;
3187 }
3188 }
3189
3190 return;
3191
3192 trunc:
3193 nd_print_trunc(ndo);
3194 }
[mirror] the TCPdump network dissector