print-lisp.c revision 313537 
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#include <string.h>
104#include <stdlib.h>
105
106#include "ip.h"
107#include "ip6.h"
108
109#include "extract.h"
110#include "addrtoname.h"
111
112static const char tstr[] = " [|LISP]";
113
114#define IPv4_AFI			1
115#define IPv6_AFI			2
116#define TYPE_INDEX			4
117#define LISP_MAP_NOTIFY_IBIT_MASK	8
118#define LISP_MAP_REGISTER_IBIT_MASK	2
119
120enum {
121	LISP_MAP_REQUEST = 1,
122	LISP_MAP_REPLY,
123	LISP_MAP_REGISTER,
124	LISP_MAP_NOTIFY,
125	LISP_ENCAPSULATED_CONTROL_MESSAGE = 8
126};
127
128enum {
129	LISP_AUTH_NONE,
130	LISP_AUTH_SHA1,
131	LISP_AUTH_SHA256
132};
133
134static const struct tok lisp_type [] = {
135	{ 0, "LISP-Reserved"			},
136	{ 1, "LISP-Map-Request"			},
137	{ 2, "LISP-Map-Reply"			},
138	{ 3, "LISP-Map-Register"		},
139	{ 4, "LISP-Map-Notify"			},
140	{ 8, "LISP-Encapsulated-Contol-Message" },
141	{ 0, NULL }
142};
143
144/*
145 * P-Bit : Request for Proxy Map-Reply from the MS/MR
146 * S-Bit : Security Enhancement. ETR is LISP-SEC enabled. draft-ietf-lisp-sec
147 * I-Bit : 128 bit xTR-ID and 64 bit Site-ID present.
148 *	   xTR-ID and Site-ID help in differentiation of xTRs in multi xTR
149 *	   and multi Site deployment scenarios.
150 * R-Bit : Built for a Reencapsulating-Tunnel-Router. Used in Traffic
151 *	   Engineering and Service Chaining
152 */
153static const struct tok map_register_hdr_flag[] = {
154	{ 0x08000000, "P-Proxy-Map-Reply"  },
155	{ 0x04000000, "S-LISP-SEC-Capable" },
156	{ 0x02000000, "I-xTR-ID-Present"   },
157	{ 0x01000000, "R-Build-For-RTR"    },
158	{ 0x00000100, "M-Want-Map-Notify"  },
159	{ 0, NULL }
160};
161
162static const struct tok map_notify_hdr_flag[] = {
163	{ 0x08000000, "I-xTR-ID-Present"   },
164	{ 0x04000000, "R-Build-For-RTR"    },
165	{ 0, NULL }
166};
167
168static const struct tok auth_type[] = {
169	{ LISP_AUTH_NONE,   "None"   },
170	{ LISP_AUTH_SHA1,   "SHA1"   },
171	{ LISP_AUTH_SHA256, "SHA256" },
172	{ 0, NULL}
173};
174
175static const struct tok lisp_eid_action[] = {
176	{ 0, "No-Action"	},
177	{ 1, "Natively-Forward" },
178	{ 2, "Send-Map-Request" },
179	{ 3, "Drop"		},
180	{ 0, NULL}
181};
182
183static const struct tok lisp_loc_flag[] = {
184	{ 0x0004, "Local-Locator" },
185	{ 0x0002, "RLoc-Probed"	  },
186	{ 0x0001, "Reachable"	  },
187	{ 0, NULL }
188};
189
190typedef struct map_register_hdr {
191	nd_uint8_t type_and_flag;
192	nd_uint8_t reserved;
193	nd_uint8_t reserved_and_flag2;
194	nd_uint8_t record_count;
195	nd_uint64_t nonce;
196	nd_uint16_t key_id;
197	nd_uint16_t auth_data_len;
198} lisp_map_register_hdr;
199
200#define MAP_REGISTER_HDR_LEN sizeof(lisp_map_register_hdr)
201
202typedef struct map_register_eid {
203	nd_uint32_t ttl;
204	nd_uint8_t locator_count;
205	nd_uint8_t eid_prefix_mask_length;
206	nd_uint8_t act_auth_inc_res;
207	nd_uint8_t reserved;
208	nd_uint8_t reserved_version_hi;
209	nd_uint8_t version_low;
210	nd_uint16_t eid_prefix_afi;
211} lisp_map_register_eid;
212
213#define MAP_REGISTER_EID_LEN sizeof(lisp_map_register_eid)
214
215typedef struct map_register_loc {
216	nd_uint8_t priority;
217	nd_uint8_t weight;
218	nd_uint8_t m_priority;
219	nd_uint8_t m_weight;
220	nd_uint16_t unused_and_flag;
221	nd_uint16_t locator_afi;
222} lisp_map_register_loc;
223
224#define MAP_REGISTER_LOC_LEN sizeof(lisp_map_register_loc)
225
226static inline uint8_t extract_lisp_type(uint8_t);
227static inline uint8_t is_xtr_data_present(uint8_t , uint8_t);
228static void lisp_hdr_flag(netdissect_options *, const lisp_map_register_hdr *);
229static void action_flag(netdissect_options *, uint8_t);
230static void loc_hdr_flag(netdissect_options *, uint16_t);
231
232void lisp_print(netdissect_options *ndo, const u_char *bp, u_int length)
233{
234	uint8_t type;
235	uint8_t mask_len;
236	uint8_t loc_count;
237	uint8_t xtr_present;
238	uint8_t record_count;
239	uint16_t key_id;
240	uint16_t eid_afi;
241	uint16_t loc_afi;
242	uint16_t map_version;
243	uint16_t packet_offset;
244	uint16_t auth_data_len;
245	uint32_t ttl;
246	const u_char *packet_iterator;
247	const u_char *loc_ip_pointer;
248	const lisp_map_register_hdr *lisp_hdr;
249	const lisp_map_register_eid *lisp_eid;
250	const lisp_map_register_loc *lisp_loc;
251
252	/* Check if enough bytes for header are available */
253	ND_TCHECK2(*bp, MAP_REGISTER_HDR_LEN);
254	lisp_hdr = (const lisp_map_register_hdr *) bp;
255	lisp_hdr_flag(ndo, lisp_hdr);
256	/* Supporting only MAP NOTIFY and MAP REGISTER LISP packets */
257	type = extract_lisp_type(lisp_hdr->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, lisp_hdr->type_and_flag);
263
264	/* Extract the number of EID records present */
265	auth_data_len = EXTRACT_16BITS(&lisp_hdr->auth_data_len);
266	packet_iterator = (const u_char *)(lisp_hdr);
267	packet_offset = MAP_REGISTER_HDR_LEN;
268	record_count = lisp_hdr->record_count;
269
270	if (ndo->ndo_vflag) {
271		key_id = EXTRACT_16BITS(&lisp_hdr->key_id);
272		ND_PRINT((ndo, "\n    %u record(s), ", record_count));
273		ND_PRINT((ndo, "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((ndo, " %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--)) {
287
288		ND_TCHECK2(*(packet_iterator + packet_offset), MAP_REGISTER_EID_LEN);
289		ND_PRINT((ndo, "\n"));
290		lisp_eid = (const lisp_map_register_eid *)
291				((const u_char *)lisp_hdr + packet_offset);
292		packet_offset += MAP_REGISTER_EID_LEN;
293		mask_len = lisp_eid->eid_prefix_mask_length;
294		eid_afi = EXTRACT_16BITS(&lisp_eid->eid_prefix_afi);
295		loc_count = lisp_eid->locator_count;
296
297		if (ndo->ndo_vflag) {
298			ttl = EXTRACT_32BITS(&lisp_eid->ttl);
299			ND_PRINT((ndo, "      Record TTL %u,", ttl));
300			action_flag(ndo, lisp_eid->act_auth_inc_res);
301			map_version = (((lisp_eid->reserved_version_hi) & 15 ) * 255) +
302					lisp_eid->version_low;
303			ND_PRINT((ndo, " Map Version: %u,", map_version));
304		}
305
306		switch (eid_afi) {
307		case IPv4_AFI:
308			ND_TCHECK2(*(packet_iterator + packet_offset), 4);
309			ND_PRINT((ndo, " EID %s/%u,", ipaddr_string(ndo,
310				packet_iterator + packet_offset), mask_len));
311			packet_offset += 4;
312			break;
313		case IPv6_AFI:
314			ND_TCHECK2(*(packet_iterator + packet_offset), 16);
315			ND_PRINT((ndo, " EID %s/%u,", ip6addr_string(ndo,
316				packet_iterator + packet_offset), 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((ndo, " %u locator(s)", loc_count));
328
329		while (loc_count--) {
330			ND_TCHECK2(*(packet_iterator + packet_offset), 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 = EXTRACT_16BITS(&lisp_loc->locator_afi);
335
336			if (ndo->ndo_vflag)
337				ND_PRINT((ndo, "\n       "));
338
339			switch (loc_afi) {
340			case IPv4_AFI:
341				ND_TCHECK2(*(packet_iterator + packet_offset), 4);
342				ND_PRINT((ndo, " LOC %s", ipaddr_string(ndo, loc_ip_pointer)));
343				packet_offset += 4;
344				break;
345			case IPv6_AFI:
346				ND_TCHECK2(*(packet_iterator + packet_offset), 16);
347				ND_PRINT((ndo, " LOC %s", ip6addr_string(ndo, loc_ip_pointer)));
348				packet_offset += 16;
349				break;
350			default:
351				break;
352			}
353			if (ndo->ndo_vflag) {
354				ND_PRINT((ndo, "\n          Priority/Weight %u/%u,"
355						" Multicast Priority/Weight %u/%u,",
356						lisp_loc->priority, lisp_loc->weight,
357						lisp_loc->m_priority, lisp_loc->m_weight));
358				loc_hdr_flag(ndo, EXTRACT_16BITS(&lisp_loc->unused_and_flag));
359			}
360		}
361	}
362
363	/*
364	 * Print xTR and Site ID. Handle the fact that the packet could be invalid.
365	 * If the xTR_ID_Present bit is not set, and we still have data to display,
366	 * show it as hex data.
367	 */
368	if (xtr_present) {
369		if (!ND_TTEST2(*(packet_iterator + packet_offset), 24))
370			goto invalid;
371		hex_print_with_offset(ndo, "\n    xTR-ID: ", packet_iterator + packet_offset, 16, 0);
372		ND_PRINT((ndo, "\n    SITE-ID: %" PRIu64,
373			EXTRACT_64BITS(packet_iterator + packet_offset + 16)));
374	} else {
375		/* Check if packet isn't over yet */
376		if (packet_iterator + packet_offset < ndo->ndo_snapend) {
377			hex_print_with_offset(ndo, "\n    Data: ", packet_iterator + packet_offset,
378				(ndo->ndo_snapend - (packet_iterator + packet_offset)), 0);
379		}
380	}
381	return;
382trunc:
383	ND_PRINT((ndo, "\n   %s", tstr));
384	return;
385invalid:
386	ND_PRINT((ndo, "\n   %s", istr));
387	return;
388}
389
390static inline uint8_t extract_lisp_type(uint8_t lisp_hdr_flags)
391{
392	return (lisp_hdr_flags) >> TYPE_INDEX;
393}
394
395static inline uint8_t is_xtr_data_present(uint8_t type, uint8_t lisp_hdr_flags)
396{
397	uint8_t xtr_present = 0;
398
399	if (type == LISP_MAP_REGISTER)
400		xtr_present = (lisp_hdr_flags) & LISP_MAP_REGISTER_IBIT_MASK;
401	else if (type == LISP_MAP_NOTIFY)
402		xtr_present = (lisp_hdr_flags) & LISP_MAP_NOTIFY_IBIT_MASK;
403
404	return xtr_present;
405}
406
407static void lisp_hdr_flag(netdissect_options *ndo, const lisp_map_register_hdr *lisp_hdr)
408{
409	uint8_t type = extract_lisp_type(lisp_hdr->type_and_flag);
410
411	if (!ndo->ndo_vflag) {
412		ND_PRINT((ndo, "%s,", tok2str(lisp_type, "unknown-type-%u", type)));
413		return;
414	} else {
415		ND_PRINT((ndo, "%s,", tok2str(lisp_type, "unknown-type-%u", type)));
416	}
417
418	if (type == LISP_MAP_REGISTER) {
419		ND_PRINT((ndo, " flags [%s],", bittok2str(map_register_hdr_flag,
420			 "none", EXTRACT_32BITS(lisp_hdr))));
421	} else if (type == LISP_MAP_NOTIFY) {
422		ND_PRINT((ndo, " flags [%s],", bittok2str(map_notify_hdr_flag,
423			 "none", EXTRACT_32BITS(lisp_hdr))));
424	}
425
426	return;
427}
428
429static void action_flag(netdissect_options *ndo, uint8_t act_auth_inc_res)
430{
431	uint8_t action;
432	uint8_t authoritative;
433
434	authoritative  = ((act_auth_inc_res >> 4) & 1);
435
436	if (authoritative)
437		ND_PRINT((ndo, " Authoritative,"));
438	else
439		ND_PRINT((ndo, " Non-Authoritative,"));
440
441	action = act_auth_inc_res >> 5;
442	ND_PRINT((ndo, " %s,", tok2str(lisp_eid_action, "unknown", action)));
443}
444
445static void loc_hdr_flag(netdissect_options *ndo, uint16_t flag)
446{
447	ND_PRINT((ndo, " flags [%s],", bittok2str(lisp_loc_flag, "none", flag)));
448}
449
450