xref: /netbsd-src/external/bsd/tcpdump/dist/print-lisp.c (revision cc576e1d8e4f4078fd4e81238abca9fca216f6ec)
1 /*
2  * Copyright (c) 2015 Ritesh Ranjan (r.ranjan789@gmail.com)
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. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * netdissect printer for LISP - Locator/Identifier Separation Protocol
31  * RFC 6830
32  *
33  *
34  * The Map-Register message format is:
35  *
36  *       0                   1                   2                   3
37  *       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
38  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39  *      |Type=3 |P|S|I|R|      Reserved               |M| Record Count  |
40  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41  *      |                         Nonce . . .                           |
42  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43  *      |                         . . . Nonce                           |
44  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45  *      |            Key ID             |  Authentication Data Length   |
46  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47  *      ~                     Authentication Data                       ~
48  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49  *  |   |                          Record TTL                           |
50  *  |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51  *  R   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
52  *  e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
53  *  c   | Rsvd  |  Map-Version Number   |        EID-Prefix-AFI         |
54  *  o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
55  *  r   |                          EID-Prefix                           |
56  *  d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57  *  |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
58  *  | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
59  *  | o |        Unused Flags     |L|p|R|           Loc-AFI             |
60  *  | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61  *  |  \|                             Locator                           |
62  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63  *
64  *
65  * The Map-Notify message format is:
66  *
67  *       0                   1                   2                   3
68  *       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
69  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
70  *      |Type=4 |I|R|          Reserved                 | Record Count  |
71  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
72  *      |                         Nonce . . .                           |
73  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
74  *      |                         . . . Nonce                           |
75  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76  *      |            Key ID             |  Authentication Data Length   |
77  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
78  *      ~                     Authentication Data                       ~
79  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
80  *  |   |                          Record TTL                           |
81  *  |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
82  *  R   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
83  *  e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
84  *  c   | Rsvd  |  Map-Version Number   |         EID-Prefix-AFI        |
85  *  o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
86  *  r   |                          EID-Prefix                           |
87  *  d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
88  *  |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
89  *  | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
90  *  | o |        Unused Flags     |L|p|R|           Loc-AFI             |
91  *  | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
92  *  |  \|                             Locator                           |
93  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
94  */
95 
96 #include <sys/cdefs.h>
97 #ifndef lint
98 __RCSID("$NetBSD: print-lisp.c,v 1.2 2017/01/24 23:29:14 christos Exp $");
99 #endif
100 
101 #ifdef HAVE_CONFIG_H
102 #include "config.h"
103 #endif
104 
105 #include <netdissect-stdinc.h>
106 #include <netdissect.h>
107 #include <string.h>
108 #include <stdlib.h>
109 
110 #include "ip.h"
111 #include "ip6.h"
112 
113 #include "extract.h"
114 #include "addrtoname.h"
115 
116 static const char tstr[] = " [|LISP]";
117 
118 #define IPv4_AFI			1
119 #define IPv6_AFI			2
120 #define TYPE_INDEX			4
121 #define LISP_MAP_NOTIFY_IBIT_MASK	8
122 #define LISP_MAP_REGISTER_IBIT_MASK	2
123 
124 enum {
125 	LISP_MAP_REQUEST = 1,
126 	LISP_MAP_REPLY,
127 	LISP_MAP_REGISTER,
128 	LISP_MAP_NOTIFY,
129 	LISP_ENCAPSULATED_CONTROL_MESSAGE = 8
130 };
131 
132 enum {
133 	LISP_AUTH_NONE,
134 	LISP_AUTH_SHA1,
135 	LISP_AUTH_SHA256
136 };
137 
138 static const struct tok lisp_type [] = {
139 	{ 0, "LISP-Reserved"			},
140 	{ 1, "LISP-Map-Request"			},
141 	{ 2, "LISP-Map-Reply"			},
142 	{ 3, "LISP-Map-Register"		},
143 	{ 4, "LISP-Map-Notify"			},
144 	{ 8, "LISP-Encapsulated-Contol-Message" },
145 	{ 0, NULL }
146 };
147 
148 /*
149  * P-Bit : Request for Proxy Map-Reply from the MS/MR
150  * S-Bit : Security Enhancement. ETR is LISP-SEC enabled. draft-ietf-lisp-sec
151  * I-Bit : 128 bit xTR-ID and 64 bit Site-ID present.
152  *	   xTR-ID and Site-ID help in differentiation of xTRs in multi xTR
153  *	   and multi Site deployment scenarios.
154  * R-Bit : Built for a Reencapsulating-Tunnel-Router. Used in Traffic
155  *	   Engineering and Service Chaining
156  */
157 static const struct tok map_register_hdr_flag[] = {
158 	{ 0x08000000, "P-Proxy-Map-Reply"  },
159 	{ 0x04000000, "S-LISP-SEC-Capable" },
160 	{ 0x02000000, "I-xTR-ID-Present"   },
161 	{ 0x01000000, "R-Build-For-RTR"    },
162 	{ 0x00000100, "M-Want-Map-Notify"  },
163 	{ 0, NULL }
164 };
165 
166 static const struct tok map_notify_hdr_flag[] = {
167 	{ 0x08000000, "I-xTR-ID-Present"   },
168 	{ 0x04000000, "R-Build-For-RTR"    },
169 	{ 0, NULL }
170 };
171 
172 static const struct tok auth_type[] = {
173 	{ LISP_AUTH_NONE,   "None"   },
174 	{ LISP_AUTH_SHA1,   "SHA1"   },
175 	{ LISP_AUTH_SHA256, "SHA256" },
176 	{ 0, NULL}
177 };
178 
179 static const struct tok lisp_eid_action[] = {
180 	{ 0, "No-Action"	},
181 	{ 1, "Natively-Forward" },
182 	{ 2, "Send-Map-Request" },
183 	{ 3, "Drop"		},
184 	{ 0, NULL}
185 };
186 
187 static const struct tok lisp_loc_flag[] = {
188 	{ 0x0004, "Local-Locator" },
189 	{ 0x0002, "RLoc-Probed"	  },
190 	{ 0x0001, "Reachable"	  },
191 	{ 0, NULL }
192 };
193 
194 typedef struct map_register_hdr {
195 	nd_uint8_t type_and_flag;
196 	nd_uint8_t reserved;
197 	nd_uint8_t reserved_and_flag2;
198 	nd_uint8_t record_count;
199 	nd_uint64_t nonce;
200 	nd_uint16_t key_id;
201 	nd_uint16_t auth_data_len;
202 } lisp_map_register_hdr;
203 
204 #define MAP_REGISTER_HDR_LEN sizeof(lisp_map_register_hdr)
205 
206 typedef struct map_register_eid {
207 	nd_uint32_t ttl;
208 	nd_uint8_t locator_count;
209 	nd_uint8_t eid_prefix_mask_length;
210 	nd_uint8_t act_auth_inc_res;
211 	nd_uint8_t reserved;
212 	nd_uint8_t reserved_version_hi;
213 	nd_uint8_t version_low;
214 	nd_uint16_t eid_prefix_afi;
215 } lisp_map_register_eid;
216 
217 #define MAP_REGISTER_EID_LEN sizeof(lisp_map_register_eid)
218 
219 typedef struct map_register_loc {
220 	nd_uint8_t priority;
221 	nd_uint8_t weight;
222 	nd_uint8_t m_priority;
223 	nd_uint8_t m_weight;
224 	nd_uint16_t unused_and_flag;
225 	nd_uint16_t locator_afi;
226 } lisp_map_register_loc;
227 
228 #define MAP_REGISTER_LOC_LEN sizeof(lisp_map_register_loc)
229 
230 static inline uint8_t extract_lisp_type(uint8_t);
231 static inline uint8_t is_xtr_data_present(uint8_t , uint8_t);
232 static void lisp_hdr_flag(netdissect_options *, const lisp_map_register_hdr *);
233 static void action_flag(netdissect_options *, uint8_t);
234 static void loc_hdr_flag(netdissect_options *, uint16_t);
235 
236 void lisp_print(netdissect_options *ndo, const u_char *bp, u_int length)
237 {
238 	uint8_t type;
239 	uint8_t mask_len;
240 	uint8_t loc_count;
241 	uint8_t xtr_present;
242 	uint8_t record_count;
243 	uint16_t key_id;
244 	uint16_t eid_afi;
245 	uint16_t loc_afi;
246 	uint16_t map_version;
247 	uint16_t packet_offset;
248 	uint16_t auth_data_len;
249 	uint32_t ttl;
250 	const u_char *packet_iterator;
251 	const u_char *loc_ip_pointer;
252 	const lisp_map_register_hdr *lisp_hdr;
253 	const lisp_map_register_eid *lisp_eid;
254 	const lisp_map_register_loc *lisp_loc;
255 
256 	/* Check if enough bytes for header are available */
257 	ND_TCHECK2(*bp, MAP_REGISTER_HDR_LEN);
258 	lisp_hdr = (const lisp_map_register_hdr *) bp;
259 	lisp_hdr_flag(ndo, lisp_hdr);
260 	/* Supporting only MAP NOTIFY and MAP REGISTER LISP packets */
261 	type = extract_lisp_type(lisp_hdr->type_and_flag);
262 	if ((type != LISP_MAP_REGISTER) && (type != LISP_MAP_NOTIFY))
263 		return;
264 
265 	/* Find if the packet contains xTR and Site-ID data */
266 	xtr_present = is_xtr_data_present(type, lisp_hdr->type_and_flag);
267 
268 	/* Extract the number of EID records present */
269 	auth_data_len = EXTRACT_16BITS(&lisp_hdr->auth_data_len);
270 	packet_iterator = (const u_char *)(lisp_hdr);
271 	packet_offset = MAP_REGISTER_HDR_LEN;
272 	record_count = lisp_hdr->record_count;
273 
274 	if (ndo->ndo_vflag) {
275 		key_id = EXTRACT_16BITS(&lisp_hdr->key_id);
276 		ND_PRINT((ndo, "\n    %u record(s), ", record_count));
277 		ND_PRINT((ndo, "Authentication %s,",
278 			tok2str(auth_type, "unknown-type", key_id)));
279 		hex_print(ndo, "\n    Authentication-Data: ", packet_iterator +
280 						packet_offset, auth_data_len);
281 	} else {
282 		ND_PRINT((ndo, " %u record(s),", record_count));
283 	}
284 	packet_offset += auth_data_len;
285 
286 	if (record_count == 0)
287 		goto invalid;
288 
289 	/* Print all the EID records */
290 	while ((length > packet_offset) && (record_count--)) {
291 
292 		ND_TCHECK2(*(packet_iterator + packet_offset), MAP_REGISTER_EID_LEN);
293 		ND_PRINT((ndo, "\n"));
294 		lisp_eid = (const lisp_map_register_eid *)
295 				((const u_char *)lisp_hdr + packet_offset);
296 		packet_offset += MAP_REGISTER_EID_LEN;
297 		mask_len = lisp_eid->eid_prefix_mask_length;
298 		eid_afi = EXTRACT_16BITS(&lisp_eid->eid_prefix_afi);
299 		loc_count = lisp_eid->locator_count;
300 
301 		if (ndo->ndo_vflag) {
302 			ttl = EXTRACT_32BITS(&lisp_eid->ttl);
303 			ND_PRINT((ndo, "      Record TTL %u,", ttl));
304 			action_flag(ndo, lisp_eid->act_auth_inc_res);
305 			map_version = (((lisp_eid->reserved_version_hi) & 15 ) * 255) +
306 					lisp_eid->version_low;
307 			ND_PRINT((ndo, " Map Version: %u,", map_version));
308 		}
309 
310 		switch (eid_afi) {
311 		case IPv4_AFI:
312 			ND_TCHECK2(*(packet_iterator + packet_offset), 4);
313 			ND_PRINT((ndo, " EID %s/%u,", ipaddr_string(ndo,
314 				packet_iterator + packet_offset), mask_len));
315 			packet_offset += 4;
316 			break;
317 		case IPv6_AFI:
318 			ND_TCHECK2(*(packet_iterator + packet_offset), 16);
319 			ND_PRINT((ndo, " EID %s/%u,", ip6addr_string(ndo,
320 				packet_iterator + packet_offset), mask_len));
321 			packet_offset += 16;
322 			break;
323 		default:
324 			/*
325 			 * No support for LCAF right now.
326 			 */
327 			return;
328 			break;
329 		}
330 
331 		ND_PRINT((ndo, " %u locator(s)", loc_count));
332 
333 		while (loc_count--) {
334 			ND_TCHECK2(*(packet_iterator + packet_offset), MAP_REGISTER_LOC_LEN);
335 			lisp_loc = (const lisp_map_register_loc *) (packet_iterator + packet_offset);
336 			loc_ip_pointer = (const u_char *) (lisp_loc + 1);
337 			packet_offset += MAP_REGISTER_LOC_LEN;
338 			loc_afi = EXTRACT_16BITS(&lisp_loc->locator_afi);
339 
340 			if (ndo->ndo_vflag)
341 				ND_PRINT((ndo, "\n       "));
342 
343 			switch (loc_afi) {
344 			case IPv4_AFI:
345 				ND_TCHECK2(*(packet_iterator + packet_offset), 4);
346 				ND_PRINT((ndo, " LOC %s", ipaddr_string(ndo, loc_ip_pointer)));
347 				packet_offset += 4;
348 				break;
349 			case IPv6_AFI:
350 				ND_TCHECK2(*(packet_iterator + packet_offset), 16);
351 				ND_PRINT((ndo, " LOC %s", ip6addr_string(ndo, loc_ip_pointer)));
352 				packet_offset += 16;
353 				break;
354 			default:
355 				break;
356 			}
357 			if (ndo->ndo_vflag) {
358 				ND_PRINT((ndo, "\n          Priority/Weight %u/%u,"
359 						" Multicast Priority/Weight %u/%u,",
360 						lisp_loc->priority, lisp_loc->weight,
361 						lisp_loc->m_priority, lisp_loc->m_weight));
362 				loc_hdr_flag(ndo, EXTRACT_16BITS(&lisp_loc->unused_and_flag));
363 			}
364 		}
365 	}
366 
367 	/*
368 	 * Print xTR and Site ID. Handle the fact that the packet could be invalid.
369 	 * If the xTR_ID_Present bit is not set, and we still have data to display,
370 	 * show it as hex data.
371 	 */
372 	if (xtr_present) {
373 		if (!ND_TTEST2(*(packet_iterator + packet_offset), 24))
374 			goto invalid;
375 		hex_print_with_offset(ndo, "\n    xTR-ID: ", packet_iterator + packet_offset, 16, 0);
376 		ND_PRINT((ndo, "\n    SITE-ID: %" PRIu64,
377 			EXTRACT_64BITS(packet_iterator + packet_offset + 16)));
378 	} else {
379 		/* Check if packet isn't over yet */
380 		if (packet_iterator + packet_offset < ndo->ndo_snapend) {
381 			hex_print_with_offset(ndo, "\n    Data: ", packet_iterator + packet_offset,
382 				(ndo->ndo_snapend - (packet_iterator + packet_offset)), 0);
383 		}
384 	}
385 	return;
386 trunc:
387 	ND_PRINT((ndo, "\n   %s", tstr));
388 	return;
389 invalid:
390 	ND_PRINT((ndo, "\n   %s", istr));
391 	return;
392 }
393 
394 static inline uint8_t extract_lisp_type(uint8_t lisp_hdr_flags)
395 {
396 	return (lisp_hdr_flags) >> TYPE_INDEX;
397 }
398 
399 static inline uint8_t is_xtr_data_present(uint8_t type, uint8_t lisp_hdr_flags)
400 {
401 	uint8_t xtr_present = 0;
402 
403 	if (type == LISP_MAP_REGISTER)
404 		xtr_present = (lisp_hdr_flags) & LISP_MAP_REGISTER_IBIT_MASK;
405 	else if (type == LISP_MAP_NOTIFY)
406 		xtr_present = (lisp_hdr_flags) & LISP_MAP_NOTIFY_IBIT_MASK;
407 
408 	return xtr_present;
409 }
410 
411 static void lisp_hdr_flag(netdissect_options *ndo, const lisp_map_register_hdr *lisp_hdr)
412 {
413 	uint8_t type = extract_lisp_type(lisp_hdr->type_and_flag);
414 
415 	if (!ndo->ndo_vflag) {
416 		ND_PRINT((ndo, "%s,", tok2str(lisp_type, "unknown-type-%u", type)));
417 		return;
418 	} else {
419 		ND_PRINT((ndo, "%s,", tok2str(lisp_type, "unknown-type-%u", type)));
420 	}
421 
422 	if (type == LISP_MAP_REGISTER) {
423 		ND_PRINT((ndo, " flags [%s],", bittok2str(map_register_hdr_flag,
424 			 "none", EXTRACT_32BITS(lisp_hdr))));
425 	} else if (type == LISP_MAP_NOTIFY) {
426 		ND_PRINT((ndo, " flags [%s],", bittok2str(map_notify_hdr_flag,
427 			 "none", EXTRACT_32BITS(lisp_hdr))));
428 	}
429 
430 	return;
431 }
432 
433 static void action_flag(netdissect_options *ndo, uint8_t act_auth_inc_res)
434 {
435 	uint8_t action;
436 	uint8_t authoritative;
437 
438 	authoritative  = ((act_auth_inc_res >> 4) & 1);
439 
440 	if (authoritative)
441 		ND_PRINT((ndo, " Authoritative,"));
442 	else
443 		ND_PRINT((ndo, " Non-Authoritative,"));
444 
445 	action = act_auth_inc_res >> 5;
446 	ND_PRINT((ndo, " %s,", tok2str(lisp_eid_action, "unknown", action)));
447 }
448 
449 static void loc_hdr_flag(netdissect_options *ndo, uint16_t flag)
450 {
451 	ND_PRINT((ndo, " flags [%s],", bittok2str(lisp_loc_flag, "none", flag)));
452 }
453 
454