• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (c) 2013 The TCPDUMP project
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that: (1) source code
6  * distributions retain the above copyright notice and this paragraph
7  * in its entirety, and (2) distributions including binary code include
8  * the above copyright notice and this paragraph in its entirety in
9  * the documentation or other materials provided with the distribution.
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
13  * FOR A PARTICULAR PURPOSE.
14  *
15  * Original code by Ola Martin Lykkja (ola.lykkja@q-free.com)
16  */
17 
18 /* \summary: ISO CALM FAST and ETSI GeoNetworking printer */
19 
20 #ifdef HAVE_CONFIG_H
21 #include "config.h"
22 #endif
23 
24 #include <netdissect-stdinc.h>
25 
26 #include "netdissect.h"
27 #include "extract.h"
28 #include "addrtoname.h"
29 
30 
31 /*
32    ETSI TS 102 636-5-1 V1.1.1 (2011-02)
33    Intelligent Transport Systems (ITS); Vehicular Communications; GeoNetworking;
34    Part 5: Transport Protocols; Sub-part 1: Basic Transport Protocol
35 
36    ETSI TS 102 636-4-1 V1.1.1 (2011-06)
37    Intelligent Transport Systems (ITS); Vehicular communications; GeoNetworking;
38    Part 4: Geographical addressing and forwarding for point-to-point and point-to-multipoint communications;
39    Sub-part 1: Media-Independent Functionality
40 */
41 
42 #define GEONET_ADDR_LEN 8
43 
44 static const struct tok msg_type_values[] = {
45 	{   0, "CAM" },
46 	{   1, "DENM" },
47 	{ 101, "TPEGM" },
48 	{ 102, "TSPDM" },
49 	{ 103, "VPM" },
50 	{ 104, "SRM" },
51 	{ 105, "SLAM" },
52 	{ 106, "ecoCAM" },
53 	{ 107, "ITM" },
54 	{ 150, "SA" },
55 	{   0, NULL }
56 };
57 
58 static void
print_btp_body(netdissect_options * ndo,const u_char * bp)59 print_btp_body(netdissect_options *ndo,
60                const u_char *bp)
61 {
62 	int version;
63 	int msg_type;
64 	const char *msg_type_str;
65 
66 	/* Assuming ItsDpuHeader */
67 	version = bp[0];
68 	msg_type = bp[1];
69 	msg_type_str = tok2str(msg_type_values, "unknown (%u)", msg_type);
70 
71 	ND_PRINT((ndo, "; ItsPduHeader v:%d t:%d-%s", version, msg_type, msg_type_str));
72 }
73 
74 static void
print_btp(netdissect_options * ndo,const u_char * bp)75 print_btp(netdissect_options *ndo,
76           const u_char *bp)
77 {
78 	uint16_t dest = EXTRACT_16BITS(bp+0);
79 	uint16_t src = EXTRACT_16BITS(bp+2);
80 	ND_PRINT((ndo, "; BTP Dst:%u Src:%u", dest, src));
81 }
82 
83 static int
print_long_pos_vector(netdissect_options * ndo,const u_char * bp)84 print_long_pos_vector(netdissect_options *ndo,
85                       const u_char *bp)
86 {
87 	uint32_t lat, lon;
88 
89 	if (!ND_TTEST2(*bp, GEONET_ADDR_LEN))
90 		return (-1);
91 	ND_PRINT((ndo, "GN_ADDR:%s ", linkaddr_string (ndo, bp, 0, GEONET_ADDR_LEN)));
92 
93 	if (!ND_TTEST2(*(bp+12), 8))
94 		return (-1);
95 	lat = EXTRACT_32BITS(bp+12);
96 	ND_PRINT((ndo, "lat:%d ", lat));
97 	lon = EXTRACT_32BITS(bp+16);
98 	ND_PRINT((ndo, "lon:%d", lon));
99 	return (0);
100 }
101 
102 
103 /*
104  * This is the top level routine of the printer.  'p' points
105  * to the geonet header of the packet.
106  */
107 void
geonet_print(netdissect_options * ndo,const u_char * bp,u_int length,const struct lladdr_info * src)108 geonet_print(netdissect_options *ndo, const u_char *bp, u_int length,
109 	     const struct lladdr_info *src)
110 {
111 	int version;
112 	int next_hdr;
113 	int hdr_type;
114 	int hdr_subtype;
115 	uint16_t payload_length;
116 	int hop_limit;
117 	const char *next_hdr_txt = "Unknown";
118 	const char *hdr_type_txt = "Unknown";
119 	int hdr_size = -1;
120 
121 	ND_PRINT((ndo, "GeoNet "));
122 	if (src != NULL)
123 		ND_PRINT((ndo, "src:%s", (src->addr_string)(ndo, src->addr)));
124 	ND_PRINT((ndo, "; "));
125 
126 	/* Process Common Header */
127 	if (length < 36)
128 		goto invalid;
129 
130 	ND_TCHECK2(*bp, 8);
131 	version = bp[0] >> 4;
132 	next_hdr = bp[0] & 0x0f;
133 	hdr_type = bp[1] >> 4;
134 	hdr_subtype = bp[1] & 0x0f;
135 	payload_length = EXTRACT_16BITS(bp+4);
136 	hop_limit = bp[7];
137 
138 	switch (next_hdr) {
139 		case 0: next_hdr_txt = "Any"; break;
140 		case 1: next_hdr_txt = "BTP-A"; break;
141 		case 2: next_hdr_txt = "BTP-B"; break;
142 		case 3: next_hdr_txt = "IPv6"; break;
143 	}
144 
145 	switch (hdr_type) {
146 		case 0: hdr_type_txt = "Any"; break;
147 		case 1: hdr_type_txt = "Beacon"; break;
148 		case 2: hdr_type_txt = "GeoUnicast"; break;
149 		case 3: switch (hdr_subtype) {
150 				case 0: hdr_type_txt = "GeoAnycastCircle"; break;
151 				case 1: hdr_type_txt = "GeoAnycastRect"; break;
152 				case 2: hdr_type_txt = "GeoAnycastElipse"; break;
153 			}
154 			break;
155 		case 4: switch (hdr_subtype) {
156 				case 0: hdr_type_txt = "GeoBroadcastCircle"; break;
157 				case 1: hdr_type_txt = "GeoBroadcastRect"; break;
158 				case 2: hdr_type_txt = "GeoBroadcastElipse"; break;
159 			}
160 			break;
161 		case 5: switch (hdr_subtype) {
162 				case 0: hdr_type_txt = "TopoScopeBcast-SH"; break;
163 				case 1: hdr_type_txt = "TopoScopeBcast-MH"; break;
164 			}
165 			break;
166 		case 6: switch (hdr_subtype) {
167 				case 0: hdr_type_txt = "LocService-Request"; break;
168 				case 1: hdr_type_txt = "LocService-Reply"; break;
169 			}
170 			break;
171 	}
172 
173 	ND_PRINT((ndo, "v:%d ", version));
174 	ND_PRINT((ndo, "NH:%d-%s ", next_hdr, next_hdr_txt));
175 	ND_PRINT((ndo, "HT:%d-%d-%s ", hdr_type, hdr_subtype, hdr_type_txt));
176 	ND_PRINT((ndo, "HopLim:%d ", hop_limit));
177 	ND_PRINT((ndo, "Payload:%d ", payload_length));
178 	if (print_long_pos_vector(ndo, bp + 8) == -1)
179 		goto trunc;
180 
181 	/* Skip Common Header */
182 	length -= 36;
183 	bp += 36;
184 
185 	/* Process Extended Headers */
186 	switch (hdr_type) {
187 		case 0: /* Any */
188 			hdr_size = 0;
189 			break;
190 		case 1: /* Beacon */
191 			hdr_size = 0;
192 			break;
193 		case 2: /* GeoUnicast */
194 			break;
195 		case 3: switch (hdr_subtype) {
196 				case 0: /* GeoAnycastCircle */
197 					break;
198 				case 1: /* GeoAnycastRect */
199 					break;
200 				case 2: /* GeoAnycastElipse */
201 					break;
202 			}
203 			break;
204 		case 4: switch (hdr_subtype) {
205 				case 0: /* GeoBroadcastCircle */
206 					break;
207 				case 1: /* GeoBroadcastRect */
208 					break;
209 				case 2: /* GeoBroadcastElipse */
210 					break;
211 			}
212 			break;
213 		case 5: switch (hdr_subtype) {
214 				case 0: /* TopoScopeBcast-SH */
215 					hdr_size = 0;
216 					break;
217 				case 1: /* TopoScopeBcast-MH */
218 					hdr_size = 68 - 36;
219 					break;
220 			}
221 			break;
222 		case 6: switch (hdr_subtype) {
223 				case 0: /* LocService-Request */
224 					break;
225 				case 1: /* LocService-Reply */
226 					break;
227 			}
228 			break;
229 	}
230 
231 	/* Skip Extended headers */
232 	if (hdr_size >= 0) {
233 		if (length < (u_int)hdr_size)
234 			goto invalid;
235 		ND_TCHECK2(*bp, hdr_size);
236 		length -= hdr_size;
237 		bp += hdr_size;
238 		switch (next_hdr) {
239 			case 0: /* Any */
240 				break;
241 			case 1:
242 			case 2: /* BTP A/B */
243 				if (length < 4)
244 					goto invalid;
245 				ND_TCHECK2(*bp, 4);
246 				print_btp(ndo, bp);
247 				length -= 4;
248 				bp += 4;
249 				if (length >= 2) {
250 					/*
251 					 * XXX - did print_btp_body()
252 					 * return if length < 2
253 					 * because this is optional,
254 					 * or was that just not
255 					 * reporting genuine errors?
256 					 */
257 					ND_TCHECK2(*bp, 2);
258 					print_btp_body(ndo, bp);
259 				}
260 				break;
261 			case 3: /* IPv6 */
262 				break;
263 		}
264 	}
265 
266 	/* Print user data part */
267 	if (ndo->ndo_vflag)
268 		ND_DEFAULTPRINT(bp, length);
269 	return;
270 
271 invalid:
272 	ND_PRINT((ndo, " Malformed (small) "));
273 	/* XXX - print the remaining data as hex? */
274 	return;
275 
276 trunc:
277 	ND_PRINT((ndo, "[|geonet]"));
278 }
279 
280 
281 /*
282  * Local Variables:
283  * c-style: whitesmith
284  * c-basic-offset: 8
285  * End:
286  */
287