xref: /freebsd/contrib/tcpdump/print-lisp.c (revision 9247238cc4b8835892a47701136b0fd073f8d67c)
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 #ifdef HAVE_CONFIG_H
98 #include <config.h>
99 #endif
100 
101 #include "netdissect-stdinc.h"
102 #include "netdissect.h"
103 
104 #include "ip.h"
105 #include "ip6.h"
106 
107 #include "extract.h"
108 #include "addrtoname.h"
109 
110 
111 #define IPv4_AFI			1
112 #define IPv6_AFI			2
113 #define TYPE_INDEX			4
114 #define LISP_MAP_NOTIFY_IBIT_MASK	8
115 #define LISP_MAP_REGISTER_IBIT_MASK	2
116 
117 enum {
118 	LISP_MAP_REQUEST = 1,
119 	LISP_MAP_REPLY,
120 	LISP_MAP_REGISTER,
121 	LISP_MAP_NOTIFY,
122 	LISP_ENCAPSULATED_CONTROL_MESSAGE = 8
123 };
124 
125 enum {
126 	LISP_AUTH_NONE,
127 	LISP_AUTH_SHA1,
128 	LISP_AUTH_SHA256
129 };
130 
131 static const struct tok lisp_type [] = {
132 	{ 0, "LISP-Reserved"			},
133 	{ 1, "LISP-Map-Request"			},
134 	{ 2, "LISP-Map-Reply"			},
135 	{ 3, "LISP-Map-Register"		},
136 	{ 4, "LISP-Map-Notify"			},
137 	{ 8, "LISP-Encapsulated-Contol-Message" },
138 	{ 0, NULL }
139 };
140 
141 /*
142  * P-Bit : Request for Proxy Map-Reply from the MS/MR
143  * S-Bit : Security Enhancement. ETR is LISP-SEC enabled. draft-ietf-lisp-sec
144  * I-Bit : 128 bit xTR-ID and 64 bit Site-ID present.
145  *	   xTR-ID and Site-ID help in differentiation of xTRs in multi xTR
146  *	   and multi Site deployment scenarios.
147  * R-Bit : Built for a Reencapsulating-Tunnel-Router. Used in Traffic
148  *	   Engineering and Service Chaining
149  */
150 static const struct tok map_register_hdr_flag[] = {
151 	{ 0x08000000, "P-Proxy-Map-Reply"  },
152 	{ 0x04000000, "S-LISP-SEC-Capable" },
153 	{ 0x02000000, "I-xTR-ID-Present"   },
154 	{ 0x01000000, "R-Build-For-RTR"    },
155 	{ 0x00000100, "M-Want-Map-Notify"  },
156 	{ 0, NULL }
157 };
158 
159 static const struct tok map_notify_hdr_flag[] = {
160 	{ 0x08000000, "I-xTR-ID-Present"   },
161 	{ 0x04000000, "R-Build-For-RTR"    },
162 	{ 0, NULL }
163 };
164 
165 static const struct tok auth_type[] = {
166 	{ LISP_AUTH_NONE,   "None"   },
167 	{ LISP_AUTH_SHA1,   "SHA1"   },
168 	{ LISP_AUTH_SHA256, "SHA256" },
169 	{ 0, NULL}
170 };
171 
172 static const struct tok lisp_eid_action[] = {
173 	{ 0, "No-Action"	},
174 	{ 1, "Natively-Forward" },
175 	{ 2, "Send-Map-Request" },
176 	{ 3, "Drop"		},
177 	{ 0, NULL}
178 };
179 
180 static const struct tok lisp_loc_flag[] = {
181 	{ 0x0004, "Local-Locator" },
182 	{ 0x0002, "RLoc-Probed"	  },
183 	{ 0x0001, "Reachable"	  },
184 	{ 0, NULL }
185 };
186 
187 typedef struct map_register_hdr {
188 	nd_uint8_t type_and_flag;
189 	nd_uint8_t reserved;
190 	nd_uint8_t reserved_and_flag2;
191 	nd_uint8_t record_count;
192 	nd_uint64_t nonce;
193 	nd_uint16_t key_id;
194 	nd_uint16_t auth_data_len;
195 } lisp_map_register_hdr;
196 
197 #define MAP_REGISTER_HDR_LEN sizeof(lisp_map_register_hdr)
198 
199 typedef struct map_register_eid {
200 	nd_uint32_t ttl;
201 	nd_uint8_t locator_count;
202 	nd_uint8_t eid_prefix_mask_length;
203 	nd_uint8_t act_auth_inc_res;
204 	nd_uint8_t reserved;
205 	nd_uint16_t reserved_and_version;
206 	nd_uint16_t eid_prefix_afi;
207 } lisp_map_register_eid;
208 
209 #define MAP_REGISTER_EID_LEN sizeof(lisp_map_register_eid)
210 
211 typedef struct map_register_loc {
212 	nd_uint8_t priority;
213 	nd_uint8_t weight;
214 	nd_uint8_t m_priority;
215 	nd_uint8_t m_weight;
216 	nd_uint16_t unused_and_flag;
217 	nd_uint16_t locator_afi;
218 } lisp_map_register_loc;
219 
220 #define MAP_REGISTER_LOC_LEN sizeof(lisp_map_register_loc)
221 
222 static uint8_t extract_lisp_type(uint8_t);
223 static uint8_t is_xtr_data_present(uint8_t, uint8_t);
224 static void lisp_hdr_flag(netdissect_options *, const lisp_map_register_hdr *);
225 static void action_flag(netdissect_options *, uint8_t);
226 static void loc_hdr_flag(netdissect_options *, uint16_t);
227 
228 void
229 lisp_print(netdissect_options *ndo, const u_char *bp, u_int length)
230 {
231 	uint8_t type_and_flag;
232 	uint8_t type;
233 	uint8_t mask_len;
234 	uint8_t loc_count;
235 	uint8_t xtr_present;
236 	uint8_t record_count;
237 	uint16_t key_id;
238 	uint16_t eid_afi;
239 	uint16_t loc_afi;
240 	uint16_t map_version;
241 	uint16_t packet_offset;
242 	uint16_t auth_data_len;
243 	uint32_t ttl;
244 	const u_char *packet_iterator;
245 	const u_char *loc_ip_pointer;
246 	const lisp_map_register_hdr *lisp_hdr;
247 	const lisp_map_register_eid *lisp_eid;
248 	const lisp_map_register_loc *lisp_loc;
249 
250 	ndo->ndo_protocol = "lisp";
251 	/* Check if enough bytes for header are available */
252 	ND_TCHECK_LEN(bp, MAP_REGISTER_HDR_LEN);
253 	lisp_hdr = (const lisp_map_register_hdr *) bp;
254 	lisp_hdr_flag(ndo, lisp_hdr);
255 	/* Supporting only MAP NOTIFY and MAP REGISTER LISP packets */
256 	type_and_flag = GET_U_1(lisp_hdr->type_and_flag);
257 	type = extract_lisp_type(type_and_flag);
258 	if ((type != LISP_MAP_REGISTER) && (type != LISP_MAP_NOTIFY))
259 		return;
260 
261 	/* Find if the packet contains xTR and Site-ID data */
262 	xtr_present = is_xtr_data_present(type, type_and_flag);
263 
264 	/* Extract the number of EID records present */
265 	auth_data_len = GET_BE_U_2(lisp_hdr->auth_data_len);
266 	packet_iterator = (const u_char *)(lisp_hdr);
267 	packet_offset = MAP_REGISTER_HDR_LEN;
268 	record_count = GET_U_1(lisp_hdr->record_count);
269 
270 	if (ndo->ndo_vflag) {
271 		key_id = GET_BE_U_2(lisp_hdr->key_id);
272 		ND_PRINT("\n    %u record(s), ", record_count);
273 		ND_PRINT("Authentication %s,",
274 			tok2str(auth_type, "unknown-type", key_id));
275 		hex_print(ndo, "\n    Authentication-Data: ", packet_iterator +
276 						packet_offset, auth_data_len);
277 	} else {
278 		ND_PRINT(" %u record(s),", record_count);
279 	}
280 	packet_offset += auth_data_len;
281 
282 	if (record_count == 0)
283 		goto invalid;
284 
285 	/* Print all the EID records */
286 	while ((length > packet_offset) && (record_count != 0)) {
287 		record_count--;
288 		ND_TCHECK_LEN(packet_iterator + packet_offset,
289 			      MAP_REGISTER_EID_LEN);
290 		ND_PRINT("\n");
291 		lisp_eid = (const lisp_map_register_eid *)
292 				((const u_char *)lisp_hdr + packet_offset);
293 		packet_offset += MAP_REGISTER_EID_LEN;
294 		mask_len = GET_U_1(lisp_eid->eid_prefix_mask_length);
295 		eid_afi = GET_BE_U_2(lisp_eid->eid_prefix_afi);
296 		loc_count = GET_U_1(lisp_eid->locator_count);
297 
298 		if (ndo->ndo_vflag) {
299 			ttl = GET_BE_U_4(lisp_eid->ttl);
300 			ND_PRINT("      Record TTL %u,", ttl);
301 			action_flag(ndo, GET_U_1(lisp_eid->act_auth_inc_res));
302 			map_version = GET_BE_U_2(lisp_eid->reserved_and_version) & 0x0FFF;
303 			ND_PRINT(" Map Version: %u,", map_version);
304 		}
305 
306 		switch (eid_afi) {
307 		case IPv4_AFI:
308 			ND_PRINT(" EID %s/%u,",
309 				GET_IPADDR_STRING(packet_iterator + packet_offset),
310 				mask_len);
311 			packet_offset += 4;
312 			break;
313 		case IPv6_AFI:
314 			ND_PRINT(" EID %s/%u,",
315 				GET_IP6ADDR_STRING(packet_iterator + packet_offset),
316 				mask_len);
317 			packet_offset += 16;
318 			break;
319 		default:
320 			/*
321 			 * No support for LCAF right now.
322 			 */
323 			return;
324 			break;
325 		}
326 
327 		ND_PRINT(" %u locator(s)", loc_count);
328 
329 		while (loc_count != 0) {
330 			loc_count--;
331 			ND_TCHECK_LEN(packet_iterator + packet_offset,
332 				      MAP_REGISTER_LOC_LEN);
333 			lisp_loc = (const lisp_map_register_loc *) (packet_iterator + packet_offset);
334 			loc_ip_pointer = (const u_char *) (lisp_loc + 1);
335 			packet_offset += MAP_REGISTER_LOC_LEN;
336 			loc_afi = GET_BE_U_2(lisp_loc->locator_afi);
337 
338 			if (ndo->ndo_vflag)
339 				ND_PRINT("\n       ");
340 
341 			switch (loc_afi) {
342 			case IPv4_AFI:
343 				ND_TCHECK_4(packet_iterator + packet_offset);
344 				ND_PRINT(" LOC %s", GET_IPADDR_STRING(loc_ip_pointer));
345 				packet_offset += 4;
346 				break;
347 			case IPv6_AFI:
348 				ND_TCHECK_16(packet_iterator + packet_offset);
349 				ND_PRINT(" LOC %s", GET_IP6ADDR_STRING(loc_ip_pointer));
350 				packet_offset += 16;
351 				break;
352 			default:
353 				break;
354 			}
355 			if (ndo->ndo_vflag) {
356 				ND_PRINT("\n          Priority/Weight %u/%u,"
357 						" Multicast Priority/Weight %u/%u,",
358 						GET_U_1(lisp_loc->priority),
359 						GET_U_1(lisp_loc->weight),
360 						GET_U_1(lisp_loc->m_priority),
361 						GET_U_1(lisp_loc->m_weight));
362 				loc_hdr_flag(ndo,
363 					     GET_BE_U_2(lisp_loc->unused_and_flag));
364 			}
365 		}
366 	}
367 
368 	/*
369 	 * Print xTR and Site ID. Handle the fact that the packet could be invalid.
370 	 * If the xTR_ID_Present bit is not set, and we still have data to display,
371 	 * show it as hex data.
372 	 */
373 	if (xtr_present) {
374 		if (!ND_TTEST_LEN(packet_iterator + packet_offset, 24))
375 			goto invalid;
376 		hex_print(ndo, "\n    xTR-ID: ", packet_iterator + packet_offset, 16);
377 		ND_PRINT("\n    SITE-ID: %" PRIu64,
378 			GET_BE_U_8(packet_iterator + packet_offset + 16));
379 	} else {
380 		/* Check if packet isn't over yet */
381 		if (packet_iterator + packet_offset < ndo->ndo_snapend) {
382 			hex_print(ndo, "\n    Data: ", packet_iterator + packet_offset,
383 				ND_BYTES_AVAILABLE_AFTER(packet_iterator + packet_offset));
384 		}
385 	}
386 	return;
387 trunc:
388 	nd_print_trunc(ndo);
389 	return;
390 invalid:
391 	nd_print_invalid(ndo);
392 }
393 
394 static uint8_t
395 extract_lisp_type(uint8_t lisp_hdr_flags)
396 {
397 	return (lisp_hdr_flags) >> TYPE_INDEX;
398 }
399 
400 static uint8_t
401 is_xtr_data_present(uint8_t type, uint8_t lisp_hdr_flags)
402 {
403 	uint8_t xtr_present = 0;
404 
405 	if (type == LISP_MAP_REGISTER)
406 		xtr_present = (lisp_hdr_flags) & LISP_MAP_REGISTER_IBIT_MASK;
407 	else if (type == LISP_MAP_NOTIFY)
408 		xtr_present = (lisp_hdr_flags) & LISP_MAP_NOTIFY_IBIT_MASK;
409 
410 	return xtr_present;
411 }
412 
413 static void lisp_hdr_flag(netdissect_options *ndo, const lisp_map_register_hdr *lisp_hdr)
414 {
415 	uint8_t type = extract_lisp_type(GET_U_1(lisp_hdr->type_and_flag));
416 
417 	if (!ndo->ndo_vflag) {
418 		ND_PRINT("%s,", tok2str(lisp_type, "unknown-type-%u", type));
419 		return;
420 	} else {
421 		ND_PRINT("%s,", tok2str(lisp_type, "unknown-type-%u", type));
422 	}
423 
424 	if (type == LISP_MAP_REGISTER) {
425 		ND_PRINT(" flags [%s],", bittok2str(map_register_hdr_flag,
426 			 "none", GET_BE_U_4(lisp_hdr)));
427 	} else if (type == LISP_MAP_NOTIFY) {
428 		ND_PRINT(" flags [%s],", bittok2str(map_notify_hdr_flag,
429 			 "none", GET_BE_U_4(lisp_hdr)));
430 	}
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(" Authoritative,");
442 	else
443 		ND_PRINT(" Non-Authoritative,");
444 
445 	action = act_auth_inc_res >> 5;
446 	ND_PRINT(" %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(" flags [%s],", bittok2str(lisp_loc_flag, "none", flag));
452 }
453 
454