xref: /freebsd/contrib/tcpdump/print-lisp.c (revision 7937bfbc0ca53fe7cdd0d54414f9296e273a518e)
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 /* \summary: - Locator/Identifier Separation Protocol (LISP) printer */
30 
31 /*
32  * specification: RFC 6830
33  *
34  *
35  * The Map-Register message format is:
36  *
37  *       0                   1                   2                   3
38  *       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
39  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40  *      |Type=3 |P|S|I|R|      Reserved               |M| Record Count  |
41  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42  *      |                         Nonce . . .                           |
43  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
44  *      |                         . . . Nonce                           |
45  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
46  *      |            Key ID             |  Authentication Data Length   |
47  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
48  *      ~                     Authentication Data                       ~
49  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
50  *  |   |                          Record TTL                           |
51  *  |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
52  *  R   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
53  *  e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
54  *  c   | Rsvd  |  Map-Version Number   |        EID-Prefix-AFI         |
55  *  o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
56  *  r   |                          EID-Prefix                           |
57  *  d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
58  *  |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
59  *  | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
60  *  | o |        Unused Flags     |L|p|R|           Loc-AFI             |
61  *  | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
62  *  |  \|                             Locator                           |
63  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
64  *
65  *
66  * The Map-Notify message format is:
67  *
68  *       0                   1                   2                   3
69  *       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
70  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71  *      |Type=4 |I|R|          Reserved                 | Record Count  |
72  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73  *      |                         Nonce . . .                           |
74  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
75  *      |                         . . . Nonce                           |
76  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77  *      |            Key ID             |  Authentication Data Length   |
78  *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
79  *      ~                     Authentication Data                       ~
80  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
81  *  |   |                          Record TTL                           |
82  *  |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
83  *  R   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
84  *  e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
85  *  c   | Rsvd  |  Map-Version Number   |         EID-Prefix-AFI        |
86  *  o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
87  *  r   |                          EID-Prefix                           |
88  *  d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
89  *  |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
90  *  | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
91  *  | o |        Unused Flags     |L|p|R|           Loc-AFI             |
92  *  | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
93  *  |  \|                             Locator                           |
94  *  +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
95  */
96 
97 #include <config.h>
98 
99 #include "netdissect-stdinc.h"
100 #include "netdissect.h"
101 
102 #include "ip.h"
103 #include "ip6.h"
104 
105 #include "extract.h"
106 #include "addrtoname.h"
107 
108 
109 #define IPv4_AFI			1
110 #define IPv6_AFI			2
111 #define TYPE_INDEX			4
112 #define LISP_MAP_NOTIFY_IBIT_MASK	8
113 #define LISP_MAP_REGISTER_IBIT_MASK	2
114 
115 enum {
116 	LISP_MAP_REQUEST = 1,
117 	LISP_MAP_REPLY,
118 	LISP_MAP_REGISTER,
119 	LISP_MAP_NOTIFY,
120 	LISP_ENCAPSULATED_CONTROL_MESSAGE = 8
121 };
122 
123 enum {
124 	LISP_AUTH_NONE,
125 	LISP_AUTH_SHA1,
126 	LISP_AUTH_SHA256
127 };
128 
129 static const struct tok lisp_type [] = {
130 	{ 0, "LISP-Reserved"			 },
131 	{ 1, "LISP-Map-Request"			 },
132 	{ 2, "LISP-Map-Reply"			 },
133 	{ 3, "LISP-Map-Register"		 },
134 	{ 4, "LISP-Map-Notify"			 },
135 	{ 8, "LISP-Encapsulated-Control-Message" },
136 	{ 0, NULL }
137 };
138 
139 /*
140  * P-Bit : Request for Proxy Map-Reply from the MS/MR
141  * S-Bit : Security Enhancement. ETR is LISP-SEC enabled. draft-ietf-lisp-sec
142  * I-Bit : 128 bit xTR-ID and 64 bit Site-ID present.
143  *	   xTR-ID and Site-ID help in differentiation of xTRs in multi xTR
144  *	   and multi Site deployment scenarios.
145  * R-Bit : Built for a Reencapsulating-Tunnel-Router. Used in Traffic
146  *	   Engineering and Service Chaining
147  */
148 static const struct tok map_register_hdr_flag[] = {
149 	{ 0x08000000, "P-Proxy-Map-Reply"  },
150 	{ 0x04000000, "S-LISP-SEC-Capable" },
151 	{ 0x02000000, "I-xTR-ID-Present"   },
152 	{ 0x01000000, "R-Build-For-RTR"    },
153 	{ 0x00000100, "M-Want-Map-Notify"  },
154 	{ 0, NULL }
155 };
156 
157 static const struct tok map_notify_hdr_flag[] = {
158 	{ 0x08000000, "I-xTR-ID-Present"   },
159 	{ 0x04000000, "R-Build-For-RTR"    },
160 	{ 0, NULL }
161 };
162 
163 static const struct tok auth_type[] = {
164 	{ LISP_AUTH_NONE,   "None"   },
165 	{ LISP_AUTH_SHA1,   "SHA1"   },
166 	{ LISP_AUTH_SHA256, "SHA256" },
167 	{ 0, NULL}
168 };
169 
170 static const struct tok lisp_eid_action[] = {
171 	{ 0, "No-Action"	},
172 	{ 1, "Natively-Forward" },
173 	{ 2, "Send-Map-Request" },
174 	{ 3, "Drop"		},
175 	{ 0, NULL}
176 };
177 
178 static const struct tok lisp_loc_flag[] = {
179 	{ 0x0004, "Local-Locator" },
180 	{ 0x0002, "RLoc-Probed"	  },
181 	{ 0x0001, "Reachable"	  },
182 	{ 0, NULL }
183 };
184 
185 typedef struct map_register_hdr {
186 	nd_uint8_t type_and_flag;
187 	nd_uint8_t reserved;
188 	nd_uint8_t reserved_and_flag2;
189 	nd_uint8_t record_count;
190 	nd_uint64_t nonce;
191 	nd_uint16_t key_id;
192 	nd_uint16_t auth_data_len;
193 } lisp_map_register_hdr;
194 
195 #define MAP_REGISTER_HDR_LEN sizeof(lisp_map_register_hdr)
196 
197 typedef struct map_register_eid {
198 	nd_uint32_t ttl;
199 	nd_uint8_t locator_count;
200 	nd_uint8_t eid_prefix_mask_length;
201 	nd_uint8_t act_auth_inc_res;
202 	nd_uint8_t reserved;
203 	nd_uint16_t reserved_and_version;
204 	nd_uint16_t eid_prefix_afi;
205 } lisp_map_register_eid;
206 
207 #define MAP_REGISTER_EID_LEN sizeof(lisp_map_register_eid)
208 
209 typedef struct map_register_loc {
210 	nd_uint8_t priority;
211 	nd_uint8_t weight;
212 	nd_uint8_t m_priority;
213 	nd_uint8_t m_weight;
214 	nd_uint16_t unused_and_flag;
215 	nd_uint16_t locator_afi;
216 } lisp_map_register_loc;
217 
218 #define MAP_REGISTER_LOC_LEN sizeof(lisp_map_register_loc)
219 
220 static uint8_t extract_lisp_type(uint8_t);
221 static uint8_t is_xtr_data_present(uint8_t, uint8_t);
222 static void lisp_hdr_flag(netdissect_options *, const lisp_map_register_hdr *);
223 static void action_flag(netdissect_options *, uint8_t);
224 static void loc_hdr_flag(netdissect_options *, uint16_t);
225 
226 void
227 lisp_print(netdissect_options *ndo, const u_char *bp, u_int length)
228 {
229 	uint8_t type_and_flag;
230 	uint8_t type;
231 	uint8_t mask_len;
232 	uint8_t loc_count;
233 	uint8_t xtr_present;
234 	uint8_t record_count;
235 	uint16_t key_id;
236 	uint16_t eid_afi;
237 	uint16_t loc_afi;
238 	uint16_t map_version;
239 	uint16_t packet_offset;
240 	uint16_t auth_data_len;
241 	uint32_t ttl;
242 	const u_char *packet_iterator;
243 	const u_char *loc_ip_pointer;
244 	const lisp_map_register_hdr *lisp_hdr;
245 	const lisp_map_register_eid *lisp_eid;
246 	const lisp_map_register_loc *lisp_loc;
247 
248 	ndo->ndo_protocol = "lisp";
249 	/* Check if enough bytes for header are available */
250 	ND_TCHECK_LEN(bp, MAP_REGISTER_HDR_LEN);
251 	lisp_hdr = (const lisp_map_register_hdr *) bp;
252 	lisp_hdr_flag(ndo, lisp_hdr);
253 	/* Supporting only MAP NOTIFY and MAP REGISTER LISP packets */
254 	type_and_flag = GET_U_1(lisp_hdr->type_and_flag);
255 	type = extract_lisp_type(type_and_flag);
256 	if ((type != LISP_MAP_REGISTER) && (type != LISP_MAP_NOTIFY))
257 		return;
258 
259 	/* Find if the packet contains xTR and Site-ID data */
260 	xtr_present = is_xtr_data_present(type, type_and_flag);
261 
262 	/* Extract the number of EID records present */
263 	auth_data_len = GET_BE_U_2(lisp_hdr->auth_data_len);
264 	packet_iterator = (const u_char *)(lisp_hdr);
265 	packet_offset = MAP_REGISTER_HDR_LEN;
266 	record_count = GET_U_1(lisp_hdr->record_count);
267 
268 	if (ndo->ndo_vflag) {
269 		key_id = GET_BE_U_2(lisp_hdr->key_id);
270 		ND_PRINT("\n    %u record(s), ", record_count);
271 		ND_PRINT("Authentication %s,",
272 			tok2str(auth_type, "unknown-type", key_id));
273 		hex_print(ndo, "\n    Authentication-Data: ", packet_iterator +
274 						packet_offset, auth_data_len);
275 	} else {
276 		ND_PRINT(" %u record(s),", record_count);
277 	}
278 	packet_offset += auth_data_len;
279 
280 	if (record_count == 0)
281 		goto invalid;
282 
283 	/* Print all the EID records */
284 	while ((length > packet_offset) && (record_count != 0)) {
285 		record_count--;
286 		ND_TCHECK_LEN(packet_iterator + packet_offset,
287 			      MAP_REGISTER_EID_LEN);
288 		ND_PRINT("\n");
289 		lisp_eid = (const lisp_map_register_eid *)
290 				((const u_char *)lisp_hdr + packet_offset);
291 		packet_offset += MAP_REGISTER_EID_LEN;
292 		mask_len = GET_U_1(lisp_eid->eid_prefix_mask_length);
293 		eid_afi = GET_BE_U_2(lisp_eid->eid_prefix_afi);
294 		loc_count = GET_U_1(lisp_eid->locator_count);
295 
296 		if (ndo->ndo_vflag) {
297 			ttl = GET_BE_U_4(lisp_eid->ttl);
298 			ND_PRINT("      Record TTL %u,", ttl);
299 			action_flag(ndo, GET_U_1(lisp_eid->act_auth_inc_res));
300 			map_version = GET_BE_U_2(lisp_eid->reserved_and_version) & 0x0FFF;
301 			ND_PRINT(" Map Version: %u,", map_version);
302 		}
303 
304 		switch (eid_afi) {
305 		case IPv4_AFI:
306 			ND_PRINT(" EID %s/%u,",
307 				GET_IPADDR_STRING(packet_iterator + packet_offset),
308 				mask_len);
309 			packet_offset += 4;
310 			break;
311 		case IPv6_AFI:
312 			ND_PRINT(" EID %s/%u,",
313 				GET_IP6ADDR_STRING(packet_iterator + packet_offset),
314 				mask_len);
315 			packet_offset += 16;
316 			break;
317 		default:
318 			/*
319 			 * No support for LCAF right now.
320 			 */
321 			return;
322 			break;
323 		}
324 
325 		ND_PRINT(" %u locator(s)", loc_count);
326 
327 		while (loc_count != 0) {
328 			loc_count--;
329 			ND_TCHECK_LEN(packet_iterator + packet_offset,
330 				      MAP_REGISTER_LOC_LEN);
331 			lisp_loc = (const lisp_map_register_loc *) (packet_iterator + packet_offset);
332 			loc_ip_pointer = (const u_char *) (lisp_loc + 1);
333 			packet_offset += MAP_REGISTER_LOC_LEN;
334 			loc_afi = GET_BE_U_2(lisp_loc->locator_afi);
335 
336 			if (ndo->ndo_vflag)
337 				ND_PRINT("\n       ");
338 
339 			switch (loc_afi) {
340 			case IPv4_AFI:
341 				ND_TCHECK_4(packet_iterator + packet_offset);
342 				ND_PRINT(" LOC %s", GET_IPADDR_STRING(loc_ip_pointer));
343 				packet_offset += 4;
344 				break;
345 			case IPv6_AFI:
346 				ND_TCHECK_16(packet_iterator + packet_offset);
347 				ND_PRINT(" LOC %s", GET_IP6ADDR_STRING(loc_ip_pointer));
348 				packet_offset += 16;
349 				break;
350 			default:
351 				break;
352 			}
353 			if (ndo->ndo_vflag) {
354 				ND_PRINT("\n          Priority/Weight %u/%u,"
355 						" Multicast Priority/Weight %u/%u,",
356 						GET_U_1(lisp_loc->priority),
357 						GET_U_1(lisp_loc->weight),
358 						GET_U_1(lisp_loc->m_priority),
359 						GET_U_1(lisp_loc->m_weight));
360 				loc_hdr_flag(ndo,
361 					     GET_BE_U_2(lisp_loc->unused_and_flag));
362 			}
363 		}
364 	}
365 
366 	/*
367 	 * Print xTR and Site ID. Handle the fact that the packet could be invalid.
368 	 * If the xTR_ID_Present bit is not set, and we still have data to display,
369 	 * show it as hex data.
370 	 */
371 	if (xtr_present) {
372 		if (!ND_TTEST_LEN(packet_iterator + packet_offset, 24))
373 			goto invalid;
374 		hex_print(ndo, "\n    xTR-ID: ", packet_iterator + packet_offset, 16);
375 		ND_PRINT("\n    SITE-ID: %" PRIu64,
376 			GET_BE_U_8(packet_iterator + packet_offset + 16));
377 	} else {
378 		/* Check if packet isn't over yet */
379 		if (packet_iterator + packet_offset < ndo->ndo_snapend) {
380 			hex_print(ndo, "\n    Data: ", packet_iterator + packet_offset,
381 				ND_BYTES_AVAILABLE_AFTER(packet_iterator + packet_offset));
382 		}
383 	}
384 	return;
385 trunc:
386 	nd_print_trunc(ndo);
387 	return;
388 invalid:
389 	nd_print_invalid(ndo);
390 }
391 
392 static uint8_t
393 extract_lisp_type(uint8_t lisp_hdr_flags)
394 {
395 	return (lisp_hdr_flags) >> TYPE_INDEX;
396 }
397 
398 static uint8_t
399 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(GET_U_1(lisp_hdr->type_and_flag));
414 
415 	if (!ndo->ndo_vflag) {
416 		ND_PRINT("%s,", tok2str(lisp_type, "unknown-type-%u", type));
417 		return;
418 	} else {
419 		ND_PRINT("%s,", tok2str(lisp_type, "unknown-type-%u", type));
420 	}
421 
422 	if (type == LISP_MAP_REGISTER) {
423 		ND_PRINT(" flags [%s],", bittok2str(map_register_hdr_flag,
424 			 "none", GET_BE_U_4(lisp_hdr)));
425 	} else if (type == LISP_MAP_NOTIFY) {
426 		ND_PRINT(" flags [%s],", bittok2str(map_notify_hdr_flag,
427 			 "none", GET_BE_U_4(lisp_hdr)));
428 	}
429 }
430 
431 static void action_flag(netdissect_options *ndo, uint8_t act_auth_inc_res)
432 {
433 	uint8_t action;
434 	uint8_t authoritative;
435 
436 	authoritative  = ((act_auth_inc_res >> 4) & 1);
437 
438 	if (authoritative)
439 		ND_PRINT(" Authoritative,");
440 	else
441 		ND_PRINT(" Non-Authoritative,");
442 
443 	action = act_auth_inc_res >> 5;
444 	ND_PRINT(" %s,", tok2str(lisp_eid_action, "unknown", action));
445 }
446 
447 static void loc_hdr_flag(netdissect_options *ndo, uint16_t flag)
448 {
449 	ND_PRINT(" flags [%s],", bittok2str(lisp_loc_flag, "none", flag));
450 }
451 
452