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 <sys/cdefs.h>
98#ifndef lint
99__RCSID("$NetBSD: print-lisp.c,v 1.4 2023/08/17 20:19:40 christos Exp $");
100#endif
101
102#ifdef HAVE_CONFIG_H
103#include <config.h>
104#endif
105
106#include "netdissect-stdinc.h"
107#include "netdissect.h"
108
109#include "ip.h"
110#include "ip6.h"
111
112#include "extract.h"
113#include "addrtoname.h"
114
115
116#define IPv4_AFI			1
117#define IPv6_AFI			2
118#define TYPE_INDEX			4
119#define LISP_MAP_NOTIFY_IBIT_MASK	8
120#define LISP_MAP_REGISTER_IBIT_MASK	2
121
122enum {
123	LISP_MAP_REQUEST = 1,
124	LISP_MAP_REPLY,
125	LISP_MAP_REGISTER,
126	LISP_MAP_NOTIFY,
127	LISP_ENCAPSULATED_CONTROL_MESSAGE = 8
128};
129
130enum {
131	LISP_AUTH_NONE,
132	LISP_AUTH_SHA1,
133	LISP_AUTH_SHA256
134};
135
136static const struct tok lisp_type [] = {
137	{ 0, "LISP-Reserved"			},
138	{ 1, "LISP-Map-Request"			},
139	{ 2, "LISP-Map-Reply"			},
140	{ 3, "LISP-Map-Register"		},
141	{ 4, "LISP-Map-Notify"			},
142	{ 8, "LISP-Encapsulated-Contol-Message" },
143	{ 0, NULL }
144};
145
146/*
147 * P-Bit : Request for Proxy Map-Reply from the MS/MR
148 * S-Bit : Security Enhancement. ETR is LISP-SEC enabled. draft-ietf-lisp-sec
149 * I-Bit : 128 bit xTR-ID and 64 bit Site-ID present.
150 *	   xTR-ID and Site-ID help in differentiation of xTRs in multi xTR
151 *	   and multi Site deployment scenarios.
152 * R-Bit : Built for a Reencapsulating-Tunnel-Router. Used in Traffic
153 *	   Engineering and Service Chaining
154 */
155static const struct tok map_register_hdr_flag[] = {
156	{ 0x08000000, "P-Proxy-Map-Reply"  },
157	{ 0x04000000, "S-LISP-SEC-Capable" },
158	{ 0x02000000, "I-xTR-ID-Present"   },
159	{ 0x01000000, "R-Build-For-RTR"    },
160	{ 0x00000100, "M-Want-Map-Notify"  },
161	{ 0, NULL }
162};
163
164static const struct tok map_notify_hdr_flag[] = {
165	{ 0x08000000, "I-xTR-ID-Present"   },
166	{ 0x04000000, "R-Build-For-RTR"    },
167	{ 0, NULL }
168};
169
170static const struct tok auth_type[] = {
171	{ LISP_AUTH_NONE,   "None"   },
172	{ LISP_AUTH_SHA1,   "SHA1"   },
173	{ LISP_AUTH_SHA256, "SHA256" },
174	{ 0, NULL}
175};
176
177static const struct tok lisp_eid_action[] = {
178	{ 0, "No-Action"	},
179	{ 1, "Natively-Forward" },
180	{ 2, "Send-Map-Request" },
181	{ 3, "Drop"		},
182	{ 0, NULL}
183};
184
185static const struct tok lisp_loc_flag[] = {
186	{ 0x0004, "Local-Locator" },
187	{ 0x0002, "RLoc-Probed"	  },
188	{ 0x0001, "Reachable"	  },
189	{ 0, NULL }
190};
191
192typedef struct map_register_hdr {
193	nd_uint8_t type_and_flag;
194	nd_uint8_t reserved;
195	nd_uint8_t reserved_and_flag2;
196	nd_uint8_t record_count;
197	nd_uint64_t nonce;
198	nd_uint16_t key_id;
199	nd_uint16_t auth_data_len;
200} lisp_map_register_hdr;
201
202#define MAP_REGISTER_HDR_LEN sizeof(lisp_map_register_hdr)
203
204typedef struct map_register_eid {
205	nd_uint32_t ttl;
206	nd_uint8_t locator_count;
207	nd_uint8_t eid_prefix_mask_length;
208	nd_uint8_t act_auth_inc_res;
209	nd_uint8_t reserved;
210	nd_uint16_t reserved_and_version;
211	nd_uint16_t eid_prefix_afi;
212} lisp_map_register_eid;
213
214#define MAP_REGISTER_EID_LEN sizeof(lisp_map_register_eid)
215
216typedef struct map_register_loc {
217	nd_uint8_t priority;
218	nd_uint8_t weight;
219	nd_uint8_t m_priority;
220	nd_uint8_t m_weight;
221	nd_uint16_t unused_and_flag;
222	nd_uint16_t locator_afi;
223} lisp_map_register_loc;
224
225#define MAP_REGISTER_LOC_LEN sizeof(lisp_map_register_loc)
226
227static uint8_t extract_lisp_type(uint8_t);
228static uint8_t is_xtr_data_present(uint8_t, uint8_t);
229static void lisp_hdr_flag(netdissect_options *, const lisp_map_register_hdr *);
230static void action_flag(netdissect_options *, uint8_t);
231static void loc_hdr_flag(netdissect_options *, uint16_t);
232
233void
234lisp_print(netdissect_options *ndo, const u_char *bp, u_int length)
235{
236	uint8_t type_and_flag;
237	uint8_t type;
238	uint8_t mask_len;
239	uint8_t loc_count;
240	uint8_t xtr_present;
241	uint8_t record_count;
242	uint16_t key_id;
243	uint16_t eid_afi;
244	uint16_t loc_afi;
245	uint16_t map_version;
246	uint16_t packet_offset;
247	uint16_t auth_data_len;
248	uint32_t ttl;
249	const u_char *packet_iterator;
250	const u_char *loc_ip_pointer;
251	const lisp_map_register_hdr *lisp_hdr;
252	const lisp_map_register_eid *lisp_eid;
253	const lisp_map_register_loc *lisp_loc;
254
255	ndo->ndo_protocol = "lisp";
256	/* Check if enough bytes for header are available */
257	ND_TCHECK_LEN(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_and_flag = GET_U_1(lisp_hdr->type_and_flag);
262	type = extract_lisp_type(type_and_flag);
263	if ((type != LISP_MAP_REGISTER) && (type != LISP_MAP_NOTIFY))
264		return;
265
266	/* Find if the packet contains xTR and Site-ID data */
267	xtr_present = is_xtr_data_present(type, type_and_flag);
268
269	/* Extract the number of EID records present */
270	auth_data_len = GET_BE_U_2(lisp_hdr->auth_data_len);
271	packet_iterator = (const u_char *)(lisp_hdr);
272	packet_offset = MAP_REGISTER_HDR_LEN;
273	record_count = GET_U_1(lisp_hdr->record_count);
274
275	if (ndo->ndo_vflag) {
276		key_id = GET_BE_U_2(lisp_hdr->key_id);
277		ND_PRINT("\n    %u record(s), ", record_count);
278		ND_PRINT("Authentication %s,",
279			tok2str(auth_type, "unknown-type", key_id));
280		hex_print(ndo, "\n    Authentication-Data: ", packet_iterator +
281						packet_offset, auth_data_len);
282	} else {
283		ND_PRINT(" %u record(s),", record_count);
284	}
285	packet_offset += auth_data_len;
286
287	if (record_count == 0)
288		goto invalid;
289
290	/* Print all the EID records */
291	while ((length > packet_offset) && (record_count != 0)) {
292		record_count--;
293		ND_TCHECK_LEN(packet_iterator + packet_offset,
294			      MAP_REGISTER_EID_LEN);
295		ND_PRINT("\n");
296		lisp_eid = (const lisp_map_register_eid *)
297				((const u_char *)lisp_hdr + packet_offset);
298		packet_offset += MAP_REGISTER_EID_LEN;
299		mask_len = GET_U_1(lisp_eid->eid_prefix_mask_length);
300		eid_afi = GET_BE_U_2(lisp_eid->eid_prefix_afi);
301		loc_count = GET_U_1(lisp_eid->locator_count);
302
303		if (ndo->ndo_vflag) {
304			ttl = GET_BE_U_4(lisp_eid->ttl);
305			ND_PRINT("      Record TTL %u,", ttl);
306			action_flag(ndo, GET_U_1(lisp_eid->act_auth_inc_res));
307			map_version = GET_BE_U_2(lisp_eid->reserved_and_version) & 0x0FFF;
308			ND_PRINT(" Map Version: %u,", map_version);
309		}
310
311		switch (eid_afi) {
312		case IPv4_AFI:
313			ND_PRINT(" EID %s/%u,",
314				GET_IPADDR_STRING(packet_iterator + packet_offset),
315				mask_len);
316			packet_offset += 4;
317			break;
318		case IPv6_AFI:
319			ND_PRINT(" EID %s/%u,",
320				GET_IP6ADDR_STRING(packet_iterator + packet_offset),
321				mask_len);
322			packet_offset += 16;
323			break;
324		default:
325			/*
326			 * No support for LCAF right now.
327			 */
328			return;
329			break;
330		}
331
332		ND_PRINT(" %u locator(s)", loc_count);
333
334		while (loc_count != 0) {
335			loc_count--;
336			ND_TCHECK_LEN(packet_iterator + packet_offset,
337				      MAP_REGISTER_LOC_LEN);
338			lisp_loc = (const lisp_map_register_loc *) (packet_iterator + packet_offset);
339			loc_ip_pointer = (const u_char *) (lisp_loc + 1);
340			packet_offset += MAP_REGISTER_LOC_LEN;
341			loc_afi = GET_BE_U_2(lisp_loc->locator_afi);
342
343			if (ndo->ndo_vflag)
344				ND_PRINT("\n       ");
345
346			switch (loc_afi) {
347			case IPv4_AFI:
348				ND_TCHECK_4(packet_iterator + packet_offset);
349				ND_PRINT(" LOC %s", GET_IPADDR_STRING(loc_ip_pointer));
350				packet_offset += 4;
351				break;
352			case IPv6_AFI:
353				ND_TCHECK_16(packet_iterator + packet_offset);
354				ND_PRINT(" LOC %s", GET_IP6ADDR_STRING(loc_ip_pointer));
355				packet_offset += 16;
356				break;
357			default:
358				break;
359			}
360			if (ndo->ndo_vflag) {
361				ND_PRINT("\n          Priority/Weight %u/%u,"
362						" Multicast Priority/Weight %u/%u,",
363						GET_U_1(lisp_loc->priority),
364						GET_U_1(lisp_loc->weight),
365						GET_U_1(lisp_loc->m_priority),
366						GET_U_1(lisp_loc->m_weight));
367				loc_hdr_flag(ndo,
368					     GET_BE_U_2(lisp_loc->unused_and_flag));
369			}
370		}
371	}
372
373	/*
374	 * Print xTR and Site ID. Handle the fact that the packet could be invalid.
375	 * If the xTR_ID_Present bit is not set, and we still have data to display,
376	 * show it as hex data.
377	 */
378	if (xtr_present) {
379		if (!ND_TTEST_LEN(packet_iterator + packet_offset, 24))
380			goto invalid;
381		hex_print(ndo, "\n    xTR-ID: ", packet_iterator + packet_offset, 16);
382		ND_PRINT("\n    SITE-ID: %" PRIu64,
383			GET_BE_U_8(packet_iterator + packet_offset + 16));
384	} else {
385		/* Check if packet isn't over yet */
386		if (packet_iterator + packet_offset < ndo->ndo_snapend) {
387			hex_print(ndo, "\n    Data: ", packet_iterator + packet_offset,
388				ND_BYTES_AVAILABLE_AFTER(packet_iterator + packet_offset));
389		}
390	}
391	return;
392trunc:
393	nd_print_trunc(ndo);
394	return;
395invalid:
396	nd_print_invalid(ndo);
397}
398
399static uint8_t
400extract_lisp_type(uint8_t lisp_hdr_flags)
401{
402	return (lisp_hdr_flags) >> TYPE_INDEX;
403}
404
405static uint8_t
406is_xtr_data_present(uint8_t type, uint8_t lisp_hdr_flags)
407{
408	uint8_t xtr_present = 0;
409
410	if (type == LISP_MAP_REGISTER)
411		xtr_present = (lisp_hdr_flags) & LISP_MAP_REGISTER_IBIT_MASK;
412	else if (type == LISP_MAP_NOTIFY)
413		xtr_present = (lisp_hdr_flags) & LISP_MAP_NOTIFY_IBIT_MASK;
414
415	return xtr_present;
416}
417
418static void lisp_hdr_flag(netdissect_options *ndo, const lisp_map_register_hdr *lisp_hdr)
419{
420	uint8_t type = extract_lisp_type(GET_U_1(lisp_hdr->type_and_flag));
421
422	if (!ndo->ndo_vflag) {
423		ND_PRINT("%s,", tok2str(lisp_type, "unknown-type-%u", type));
424		return;
425	} else {
426		ND_PRINT("%s,", tok2str(lisp_type, "unknown-type-%u", type));
427	}
428
429	if (type == LISP_MAP_REGISTER) {
430		ND_PRINT(" flags [%s],", bittok2str(map_register_hdr_flag,
431			 "none", GET_BE_U_4(lisp_hdr)));
432	} else if (type == LISP_MAP_NOTIFY) {
433		ND_PRINT(" flags [%s],", bittok2str(map_notify_hdr_flag,
434			 "none", GET_BE_U_4(lisp_hdr)));
435	}
436}
437
438static void action_flag(netdissect_options *ndo, uint8_t act_auth_inc_res)
439{
440	uint8_t action;
441	uint8_t authoritative;
442
443	authoritative  = ((act_auth_inc_res >> 4) & 1);
444
445	if (authoritative)
446		ND_PRINT(" Authoritative,");
447	else
448		ND_PRINT(" Non-Authoritative,");
449
450	action = act_auth_inc_res >> 5;
451	ND_PRINT(" %s,", tok2str(lisp_eid_action, "unknown", action));
452}
453
454static void loc_hdr_flag(netdissect_options *ndo, uint16_t flag)
455{
456	ND_PRINT(" flags [%s],", bittok2str(lisp_loc_flag, "none", flag));
457}
458
459