1 /*
2  * Copyright (c) 1998-2007 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  * Support for the Light Weight Access Point Protocol as per RFC 5412
16  *
17  * Original code by Carles Kishimoto <carles.kishimoto@gmail.com>
18  */
19 
20 #define NETDISSECT_REWORKED
21 #ifdef HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24 
25 #include <tcpdump-stdinc.h>
26 
27 #include "interface.h"
28 #include "extract.h"
29 #include "addrtoname.h"
30 
31 /*
32  * LWAPP transport (common) header
33  *      0                   1                   2                   3
34  *     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
35  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36  *    |VER| RID |C|F|L|    Frag ID    |            Length             |
37  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38  *    |          Status/WLANs         |   Payload...  |
39  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40  *
41  */
42 
43 struct lwapp_transport_header {
44     uint8_t  version;
45     uint8_t  frag_id;
46     uint8_t  length[2];
47     uint16_t status;
48 };
49 
50 /*
51  * LWAPP control header
52  *      0                   1                   2                   3
53  *      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
54  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
55  *     |  Message Type |    Seq Num    |      Msg Element Length       |
56  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57  *     |                           Session ID                          |
58  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
59  *     |      Msg Element [0..N]       |
60  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61  */
62 
63 struct lwapp_control_header {
64     uint8_t  msg_type;
65     uint8_t  seq_num;
66     uint8_t  len[2];
67     uint8_t  session_id[4];
68 };
69 
70 #define LWAPP_VERSION 0
71 #define	LWAPP_EXTRACT_VERSION(x) (((x)&0xC0)>>6)
72 #define	LWAPP_EXTRACT_RID(x) (((x)&0x38)>>3)
73 #define LWAPP_EXTRACT_CONTROL_BIT(x) (((x)&0x04)>>2)
74 
75 static const struct tok lwapp_header_bits_values[] = {
76     { 0x01, "Last Fragment Bit"},
77     { 0x02, "Fragment Bit"},
78     { 0x04, "Control Bit"},
79     { 0, NULL}
80 };
81 
82 #define	LWAPP_MSGTYPE_DISCOVERY_REQUEST			1
83 #define	LWAPP_MSGTYPE_DISCOVERY_RESPONSE		2
84 #define	LWAPP_MSGTYPE_JOIN_REQUEST			3
85 #define LWAPP_MSGTYPE_JOIN_RESPONSE			4
86 #define LWAPP_MSGTYPE_JOIN_ACK				5
87 #define LWAPP_MSGTYPE_JOIN_CONFIRM			6
88 #define LWAPP_MSGTYPE_CONFIGURE_REQUEST			10
89 #define LWAPP_MSGTYPE_CONFIGURE_RESPONSE		11
90 #define LWAPP_MSGTYPE_CONF_UPDATE_REQUEST		12
91 #define LWAPP_MSGTYPE_CONF_UPDATE_RESPONSE		13
92 #define LWAPP_MSGTYPE_WTP_EVENT_REQUEST			14
93 #define LWAPP_MSGTYPE_WTP_EVENT_RESPONSE		15
94 #define LWAPP_MSGTYPE_CHANGE_STATE_EVENT_REQUEST	16
95 #define LWAPP_MSGTYPE_CHANGE_STATE_EVENT_RESPONSE	17
96 #define LWAPP_MSGTYPE_ECHO_REQUEST			22
97 #define LWAPP_MSGTYPE_ECHO_RESPONSE			23
98 #define LWAPP_MSGTYPE_IMAGE_DATA_REQUEST		24
99 #define LWAPP_MSGTYPE_IMAGE_DATA_RESPONSE		25
100 #define LWAPP_MSGTYPE_RESET_REQUEST			26
101 #define LWAPP_MSGTYPE_RESET_RESPONSE			27
102 #define LWAPP_MSGTYPE_KEY_UPDATE_REQUEST		30
103 #define LWAPP_MSGTYPE_KEY_UPDATE_RESPONSE		31
104 #define LWAPP_MSGTYPE_PRIMARY_DISCOVERY_REQUEST		32
105 #define LWAPP_MSGTYPE_PRIMARY_DISCOVERY_RESPONSE	33
106 #define LWAPP_MSGTYPE_DATA_TRANSFER_REQUEST		34
107 #define LWAPP_MSGTYPE_DATA_TRANSFER_RESPONSE		35
108 #define LWAPP_MSGTYPE_CLEAR_CONFIG_INDICATION		36
109 #define LWAPP_MSGTYPE_WLAN_CONFIG_REQUEST		37
110 #define LWAPP_MSGTYPE_WLAN_CONFIG_RESPONSE		38
111 #define LWAPP_MSGTYPE_MOBILE_CONFIG_REQUEST		39
112 #define LWAPP_MSGTYPE_MOBILE_CONFIG_RESPONSE		40
113 
114 static const struct tok lwapp_msg_type_values[] = {
115     { LWAPP_MSGTYPE_DISCOVERY_REQUEST, "Discovery req"},
116     { LWAPP_MSGTYPE_DISCOVERY_RESPONSE, "Discovery resp"},
117     { LWAPP_MSGTYPE_JOIN_REQUEST, "Join req"},
118     { LWAPP_MSGTYPE_JOIN_RESPONSE, "Join resp"},
119     { LWAPP_MSGTYPE_JOIN_ACK, "Join ack"},
120     { LWAPP_MSGTYPE_JOIN_CONFIRM, "Join confirm"},
121     { LWAPP_MSGTYPE_CONFIGURE_REQUEST, "Configure req"},
122     { LWAPP_MSGTYPE_CONFIGURE_RESPONSE, "Configure resp"},
123     { LWAPP_MSGTYPE_CONF_UPDATE_REQUEST, "Update req"},
124     { LWAPP_MSGTYPE_CONF_UPDATE_RESPONSE, "Update resp"},
125     { LWAPP_MSGTYPE_WTP_EVENT_REQUEST, "WTP event req"},
126     { LWAPP_MSGTYPE_WTP_EVENT_RESPONSE, "WTP event resp"},
127     { LWAPP_MSGTYPE_CHANGE_STATE_EVENT_REQUEST, "Change state event req"},
128     { LWAPP_MSGTYPE_CHANGE_STATE_EVENT_RESPONSE, "Change state event resp"},
129     { LWAPP_MSGTYPE_ECHO_REQUEST, "Echo req"},
130     { LWAPP_MSGTYPE_ECHO_RESPONSE, "Echo resp"},
131     { LWAPP_MSGTYPE_IMAGE_DATA_REQUEST, "Image data req"},
132     { LWAPP_MSGTYPE_IMAGE_DATA_RESPONSE, "Image data resp"},
133     { LWAPP_MSGTYPE_RESET_REQUEST, "Channel status req"},
134     { LWAPP_MSGTYPE_RESET_RESPONSE, "Channel status resp"},
135     { LWAPP_MSGTYPE_KEY_UPDATE_REQUEST, "Key update req"},
136     { LWAPP_MSGTYPE_KEY_UPDATE_RESPONSE, "Key update resp"},
137     { LWAPP_MSGTYPE_PRIMARY_DISCOVERY_REQUEST, "Primary discovery req"},
138     { LWAPP_MSGTYPE_PRIMARY_DISCOVERY_RESPONSE, "Primary discovery resp"},
139     { LWAPP_MSGTYPE_DATA_TRANSFER_REQUEST, "Data transfer req"},
140     { LWAPP_MSGTYPE_DATA_TRANSFER_RESPONSE, "Data transfer resp"},
141     { LWAPP_MSGTYPE_CLEAR_CONFIG_INDICATION, "Clear config ind"},
142     { LWAPP_MSGTYPE_WLAN_CONFIG_REQUEST, "Wlan config req"},
143     { LWAPP_MSGTYPE_WLAN_CONFIG_RESPONSE, "Wlan config resp"},
144     { LWAPP_MSGTYPE_MOBILE_CONFIG_REQUEST, "Mobile config req"},
145     { LWAPP_MSGTYPE_MOBILE_CONFIG_RESPONSE, "Mobile config resp"},
146     { 0, NULL}
147 };
148 
149 /*
150  * LWAPP message elements
151  *
152  * 0                   1                   2                   3
153  * 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
154  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
155  * |      Type     |             Length            |   Value ...   |
156  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
157  */
158 struct lwapp_message_header {
159     uint8_t type;
160     uint8_t length[2];
161 };
162 
163 void
lwapp_control_print(netdissect_options * ndo,const u_char * pptr,u_int len,int has_ap_ident)164 lwapp_control_print(netdissect_options *ndo,
165                     const u_char *pptr, u_int len, int has_ap_ident)
166 {
167     const struct lwapp_transport_header *lwapp_trans_header;
168     const struct lwapp_control_header *lwapp_control_header;
169     const u_char *tptr;
170     int  tlen;
171     int  msg_tlen;
172 
173     tptr=pptr;
174 
175     if (has_ap_ident) {
176         /* check if enough bytes for AP identity */
177         ND_TCHECK2(*tptr, 6);
178         lwapp_trans_header = (const struct lwapp_transport_header *)(pptr+6);
179     } else {
180         lwapp_trans_header = (const struct lwapp_transport_header *)pptr;
181     }
182     ND_TCHECK(*lwapp_trans_header);
183 
184     /*
185      * Sanity checking of the header.
186      */
187     if (LWAPP_EXTRACT_VERSION(lwapp_trans_header->version) != LWAPP_VERSION) {
188 	ND_PRINT((ndo, "LWAPP version %u packet not supported",
189                LWAPP_EXTRACT_VERSION(lwapp_trans_header->version)));
190 	return;
191     }
192 
193     /* non-verbose */
194     if (ndo->ndo_vflag < 1) {
195         ND_PRINT((ndo, "LWAPPv%u, %s frame, Flags [%s], length %u",
196                LWAPP_EXTRACT_VERSION(lwapp_trans_header->version),
197                LWAPP_EXTRACT_CONTROL_BIT(lwapp_trans_header->version) ? "Control" : "Data",
198                bittok2str(lwapp_header_bits_values,"none",(lwapp_trans_header->version)&0x07),
199                len));
200         return;
201     }
202 
203     /* ok they seem to want to know everything - lets fully decode it */
204     tlen=EXTRACT_16BITS(lwapp_trans_header->length);
205 
206     ND_PRINT((ndo, "LWAPPv%u, %s frame, Radio-id %u, Flags [%s], Frag-id %u, length %u",
207            LWAPP_EXTRACT_VERSION(lwapp_trans_header->version),
208            LWAPP_EXTRACT_CONTROL_BIT(lwapp_trans_header->version) ? "Control" : "Data",
209            LWAPP_EXTRACT_RID(lwapp_trans_header->version),
210            bittok2str(lwapp_header_bits_values,"none",(lwapp_trans_header->version)&0x07),
211 	   lwapp_trans_header->frag_id,
212 	   tlen));
213 
214     if (has_ap_ident) {
215         ND_PRINT((ndo, "\n\tAP identity: %s", etheraddr_string(ndo, tptr)));
216         tptr+=sizeof(const struct lwapp_transport_header)+6;
217     } else {
218         tptr+=sizeof(const struct lwapp_transport_header);
219     }
220 
221     while(tlen>0) {
222 
223         /* did we capture enough for fully decoding the object header ? */
224         ND_TCHECK2(*tptr, sizeof(struct lwapp_control_header));
225 
226         lwapp_control_header = (const struct lwapp_control_header *)tptr;
227 	msg_tlen = EXTRACT_16BITS(lwapp_control_header->len);
228 
229 	/* print message header */
230         ND_PRINT((ndo, "\n\t  Msg type: %s (%u), Seqnum: %u, Msg len: %d, Session: 0x%08x",
231                tok2str(lwapp_msg_type_values,"Unknown",lwapp_control_header->msg_type),
232                lwapp_control_header->msg_type,
233                lwapp_control_header->seq_num,
234                msg_tlen,
235                EXTRACT_32BITS(lwapp_control_header->session_id)));
236 
237         /* did we capture enough for fully decoding the message */
238         ND_TCHECK2(*tptr, msg_tlen);
239 
240 	/* XXX - Decode sub messages for each message */
241         switch(lwapp_control_header->msg_type) {
242         case LWAPP_MSGTYPE_DISCOVERY_REQUEST:
243         case LWAPP_MSGTYPE_DISCOVERY_RESPONSE:
244         case LWAPP_MSGTYPE_JOIN_REQUEST:
245         case LWAPP_MSGTYPE_JOIN_RESPONSE:
246         case LWAPP_MSGTYPE_JOIN_ACK:
247         case LWAPP_MSGTYPE_JOIN_CONFIRM:
248         case LWAPP_MSGTYPE_CONFIGURE_REQUEST:
249         case LWAPP_MSGTYPE_CONFIGURE_RESPONSE:
250         case LWAPP_MSGTYPE_CONF_UPDATE_REQUEST:
251         case LWAPP_MSGTYPE_CONF_UPDATE_RESPONSE:
252         case LWAPP_MSGTYPE_WTP_EVENT_REQUEST:
253         case LWAPP_MSGTYPE_WTP_EVENT_RESPONSE:
254         case LWAPP_MSGTYPE_CHANGE_STATE_EVENT_REQUEST:
255         case LWAPP_MSGTYPE_CHANGE_STATE_EVENT_RESPONSE:
256         case LWAPP_MSGTYPE_ECHO_REQUEST:
257         case LWAPP_MSGTYPE_ECHO_RESPONSE:
258         case LWAPP_MSGTYPE_IMAGE_DATA_REQUEST:
259         case LWAPP_MSGTYPE_IMAGE_DATA_RESPONSE:
260         case LWAPP_MSGTYPE_RESET_REQUEST:
261         case LWAPP_MSGTYPE_RESET_RESPONSE:
262         case LWAPP_MSGTYPE_KEY_UPDATE_REQUEST:
263         case LWAPP_MSGTYPE_KEY_UPDATE_RESPONSE:
264         case LWAPP_MSGTYPE_PRIMARY_DISCOVERY_REQUEST:
265         case LWAPP_MSGTYPE_PRIMARY_DISCOVERY_RESPONSE:
266         case LWAPP_MSGTYPE_DATA_TRANSFER_REQUEST:
267         case LWAPP_MSGTYPE_DATA_TRANSFER_RESPONSE:
268         case LWAPP_MSGTYPE_CLEAR_CONFIG_INDICATION:
269         case LWAPP_MSGTYPE_WLAN_CONFIG_REQUEST:
270         case LWAPP_MSGTYPE_WLAN_CONFIG_RESPONSE:
271         case LWAPP_MSGTYPE_MOBILE_CONFIG_REQUEST:
272         case LWAPP_MSGTYPE_MOBILE_CONFIG_RESPONSE:
273         default:
274             break;
275         }
276 
277         tptr += sizeof(struct lwapp_control_header) + msg_tlen;
278         tlen -= sizeof(struct lwapp_control_header) + msg_tlen;
279     }
280     return;
281 
282  trunc:
283     ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
284 }
285 
286 void
lwapp_data_print(netdissect_options * ndo,const u_char * pptr,u_int len)287 lwapp_data_print(netdissect_options *ndo,
288                  const u_char *pptr, u_int len)
289 {
290     const struct lwapp_transport_header *lwapp_trans_header;
291     const u_char *tptr;
292     int tlen;
293 
294     tptr=pptr;
295 
296     /* check if enough bytes for AP identity */
297     ND_TCHECK2(*tptr, 6);
298     lwapp_trans_header = (const struct lwapp_transport_header *)pptr;
299     ND_TCHECK(*lwapp_trans_header);
300 
301     /*
302      * Sanity checking of the header.
303      */
304     if (LWAPP_EXTRACT_VERSION(lwapp_trans_header->version) != LWAPP_VERSION) {
305         ND_PRINT((ndo, "LWAPP version %u packet not supported",
306                LWAPP_EXTRACT_VERSION(lwapp_trans_header->version)));
307         return;
308     }
309 
310     /* non-verbose */
311     if (ndo->ndo_vflag < 1) {
312         ND_PRINT((ndo, "LWAPPv%u, %s frame, Flags [%s], length %u",
313                LWAPP_EXTRACT_VERSION(lwapp_trans_header->version),
314                LWAPP_EXTRACT_CONTROL_BIT(lwapp_trans_header->version) ? "Control" : "Data",
315                bittok2str(lwapp_header_bits_values,"none",(lwapp_trans_header->version)&0x07),
316                len));
317         return;
318     }
319 
320     /* ok they seem to want to know everything - lets fully decode it */
321     tlen=EXTRACT_16BITS(lwapp_trans_header->length);
322 
323     ND_PRINT((ndo, "LWAPPv%u, %s frame, Radio-id  %u, Flags [%s], Frag-id  %u, length %u",
324            LWAPP_EXTRACT_VERSION(lwapp_trans_header->version),
325            LWAPP_EXTRACT_CONTROL_BIT(lwapp_trans_header->version) ? "Control" : "Data",
326            LWAPP_EXTRACT_RID(lwapp_trans_header->version),
327            bittok2str(lwapp_header_bits_values,"none",(lwapp_trans_header->version)&0x07),
328            lwapp_trans_header->frag_id,
329            tlen));
330 
331     tptr+=sizeof(const struct lwapp_transport_header);
332     tlen-=sizeof(const struct lwapp_transport_header);
333 
334     /* FIX - An IEEE 802.11 frame follows - hexdump for now */
335     print_unknown_data(ndo, tptr, "\n\t", tlen);
336 
337     return;
338 
339  trunc:
340     ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
341 }
342 
343 /*
344  * Local Variables:
345  * c-style: whitesmith
346  * c-basic-offset: 8
347  * End:
348  */
349