1 /*
2 * Copyright (c) 2004 - Michael Richardson <mcr@xelerance.com>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that: (1) source code distributions
6 * retain the above copyright notice and this paragraph in its entirety, (2)
7 * distributions including binary code include the above copyright notice and
8 * this paragraph in its entirety in the documentation or other materials
9 * provided with the distribution, and (3) all advertising materials mentioning
10 * features or use of this software display the following acknowledgement:
11 * ``This product includes software developed by the University of California,
12 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
13 * the University nor the names of its contributors may be used to endorse
14 * or promote products derived from this software without specific prior
15 * written permission.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19 *
20 * Format and print EAP packets.
21 *
22 */
23
24 #ifndef lint
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-eap.c,v 1.5 2007-10-04 16:41:33 hannes Exp $";
27 #endif
28
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32
33 #include <tcpdump-stdinc.h>
34
35 #include <stdio.h>
36 #include <string.h>
37
38 #include "netdissect.h"
39 #include "interface.h"
40 #include "addrtoname.h"
41 #include "extract.h"
42 #include "ether.h"
43
44 #define EAP_FRAME_TYPE_PACKET 0
45 #define EAP_FRAME_TYPE_START 1
46 #define EAP_FRAME_TYPE_LOGOFF 2
47 #define EAP_FRAME_TYPE_KEY 3
48 #define EAP_FRAME_TYPE_ENCAP_ASF_ALERT 4
49
50 struct eap_frame_t {
51 unsigned char version;
52 unsigned char type;
53 unsigned char length[2];
54 };
55
56 static const struct tok eap_frame_type_values[] = {
57 { EAP_FRAME_TYPE_PACKET, "EAP packet" },
58 { EAP_FRAME_TYPE_START, "EAPOL start" },
59 { EAP_FRAME_TYPE_LOGOFF, "EAPOL logoff" },
60 { EAP_FRAME_TYPE_KEY, "EAPOL key" },
61 { EAP_FRAME_TYPE_ENCAP_ASF_ALERT, "Encapsulated ASF alert" },
62 { 0, NULL}
63 };
64
65 /* RFC 3748 */
66 struct eap_packet_t {
67 unsigned char code;
68 unsigned char id;
69 unsigned char length[2];
70 };
71
72 #define EAP_REQUEST 1
73 #define EAP_RESPONSE 2
74 #define EAP_SUCCESS 3
75 #define EAP_FAILURE 4
76
77 static const struct tok eap_code_values[] = {
78 { EAP_REQUEST, "Request" },
79 { EAP_RESPONSE, "Response" },
80 { EAP_SUCCESS, "Success" },
81 { EAP_FAILURE, "Failure" },
82 { 0, NULL}
83 };
84
85 #define EAP_TYPE_NO_PROPOSED 0
86 #define EAP_TYPE_IDENTITY 1
87 #define EAP_TYPE_NOTIFICATION 2
88 #define EAP_TYPE_NAK 3
89 #define EAP_TYPE_MD5_CHALLENGE 4
90 #define EAP_TYPE_OTP 5
91 #define EAP_TYPE_GTC 6
92 #define EAP_TYPE_TLS 13 /* RFC 2716 */
93 #define EAP_TYPE_SIM 18 /* RFC 4186 */
94 #define EAP_TYPE_TTLS 21 /* draft-funk-eap-ttls-v0-01.txt */
95 #define EAP_TYPE_AKA 23 /* RFC 4187 */
96 #define EAP_TYPE_FAST 43 /* RFC 4851 */
97 #define EAP_TYPE_EXPANDED_TYPES 254
98 #define EAP_TYPE_EXPERIMENTAL 255
99
100 static const struct tok eap_type_values[] = {
101 { EAP_TYPE_NO_PROPOSED, "No proposed" },
102 { EAP_TYPE_IDENTITY, "Identity" },
103 { EAP_TYPE_NOTIFICATION, "Notification" },
104 { EAP_TYPE_NAK, "Nak" },
105 { EAP_TYPE_MD5_CHALLENGE, "MD5-challenge" },
106 { EAP_TYPE_OTP, "OTP" },
107 { EAP_TYPE_GTC, "GTC" },
108 { EAP_TYPE_TLS, "TLS" },
109 { EAP_TYPE_SIM, "SIM" },
110 { EAP_TYPE_TTLS, "TTLS" },
111 { EAP_TYPE_AKA, "AKA" },
112 { EAP_TYPE_FAST, "FAST" },
113 { EAP_TYPE_EXPANDED_TYPES, "Expanded types" },
114 { EAP_TYPE_EXPERIMENTAL, "Experimental" },
115 { 0, NULL}
116 };
117
118 #define EAP_TLS_EXTRACT_BIT_L(x) (((x)&0x80)>>7)
119
120 /* RFC 2716 - EAP TLS bits */
121 #define EAP_TLS_FLAGS_LEN_INCLUDED (1 << 7)
122 #define EAP_TLS_FLAGS_MORE_FRAGMENTS (1 << 6)
123 #define EAP_TLS_FLAGS_START (1 << 5)
124
125 static const struct tok eap_tls_flags_values[] = {
126 { EAP_TLS_FLAGS_LEN_INCLUDED, "L bit" },
127 { EAP_TLS_FLAGS_MORE_FRAGMENTS, "More fragments bit"},
128 { EAP_TLS_FLAGS_START, "Start bit"},
129 { 0, NULL}
130 };
131
132 #define EAP_TTLS_VERSION(x) ((x)&0x07)
133
134 /* EAP-AKA and EAP-SIM - RFC 4187 */
135 #define EAP_AKA_CHALLENGE 1
136 #define EAP_AKA_AUTH_REJECT 2
137 #define EAP_AKA_SYNC_FAILURE 4
138 #define EAP_AKA_IDENTITY 5
139 #define EAP_SIM_START 10
140 #define EAP_SIM_CHALLENGE 11
141 #define EAP_AKA_NOTIFICATION 12
142 #define EAP_AKA_REAUTH 13
143 #define EAP_AKA_CLIENT_ERROR 14
144
145 static const struct tok eap_aka_subtype_values[] = {
146 { EAP_AKA_CHALLENGE, "Challenge" },
147 { EAP_AKA_AUTH_REJECT, "Auth reject" },
148 { EAP_AKA_SYNC_FAILURE, "Sync failure" },
149 { EAP_AKA_IDENTITY, "Identity" },
150 { EAP_SIM_START, "Start" },
151 { EAP_SIM_CHALLENGE, "Challenge" },
152 { EAP_AKA_NOTIFICATION, "Notification" },
153 { EAP_AKA_REAUTH, "Reauth" },
154 { EAP_AKA_CLIENT_ERROR, "Client error" },
155 { 0, NULL}
156 };
157
158 /*
159 * Print EAP requests / responses
160 */
161 void
eap_print(netdissect_options * ndo _U_,register const u_char * cp,u_int length _U_)162 eap_print(netdissect_options *ndo _U_,
163 register const u_char *cp,
164 u_int length _U_)
165 {
166 const struct eap_frame_t *eap;
167 const u_char *tptr;
168 u_int tlen, type, subtype;
169 int count=0, len;
170
171 tptr = cp;
172 tlen = length;
173 eap = (const struct eap_frame_t *)cp;
174 TCHECK(*eap);
175
176 /* in non-verbose mode just lets print the basic info */
177 if (vflag < 1) {
178 printf("%s (%u) v%u, len %u",
179 tok2str(eap_frame_type_values, "unknown", eap->type),
180 eap->type,
181 eap->version,
182 EXTRACT_16BITS(eap->length));
183 return;
184 }
185
186 printf("%s (%u) v%u, len %u",
187 tok2str(eap_frame_type_values, "unknown", eap->type),
188 eap->type,
189 eap->version,
190 EXTRACT_16BITS(eap->length));
191
192 tptr += sizeof(const struct eap_frame_t);
193 tlen -= sizeof(const struct eap_frame_t);
194
195 switch (eap->type) {
196 case EAP_FRAME_TYPE_PACKET:
197 type = *(tptr);
198 len = EXTRACT_16BITS(tptr+2);
199 printf(", %s (%u), id %u, len %u",
200 tok2str(eap_code_values, "unknown", type),
201 type,
202 *(tptr+1),
203 len);
204
205 if (!TTEST2(*tptr, len))
206 goto trunc;
207
208 if (type <= 2) { /* For EAP_REQUEST and EAP_RESPONSE only */
209 subtype = *(tptr+4);
210 printf("\n\t\t Type %s (%u)",
211 tok2str(eap_type_values, "unknown", *(tptr+4)),
212 *(tptr+4));
213
214 switch (subtype) {
215 case EAP_TYPE_IDENTITY:
216 if (len - 5 > 0) {
217 printf(", Identity: ");
218 safeputs((const char *)tptr+5, len-5);
219 }
220 break;
221
222 case EAP_TYPE_NOTIFICATION:
223 if (len - 5 > 0) {
224 printf(", Notification: ");
225 safeputs((const char *)tptr+5, len-5);
226 }
227 break;
228
229 case EAP_TYPE_NAK:
230 count = 5;
231
232 /*
233 * one or more octets indicating
234 * the desired authentication
235 * type one octet per type
236 */
237 while (count < len) {
238 printf(" %s (%u),",
239 tok2str(eap_type_values, "unknown", *(tptr+count)),
240 *(tptr+count));
241 count++;
242 }
243 break;
244
245 case EAP_TYPE_TTLS:
246 printf(" TTLSv%u",
247 EAP_TTLS_VERSION(*(tptr+5))); /* fall through */
248 case EAP_TYPE_TLS:
249 printf(" flags [%s] 0x%02x,",
250 bittok2str(eap_tls_flags_values, "none", *(tptr+5)),
251 *(tptr+5));
252
253 if (EAP_TLS_EXTRACT_BIT_L(*(tptr+5))) {
254 printf(" len %u", EXTRACT_32BITS(tptr+6));
255 }
256 break;
257
258 case EAP_TYPE_FAST:
259 printf(" FASTv%u",
260 EAP_TTLS_VERSION(*(tptr+5)));
261 printf(" flags [%s] 0x%02x,",
262 bittok2str(eap_tls_flags_values, "none", *(tptr+5)),
263 *(tptr+5));
264
265 if (EAP_TLS_EXTRACT_BIT_L(*(tptr+5))) {
266 printf(" len %u", EXTRACT_32BITS(tptr+6));
267 }
268
269 /* FIXME - TLV attributes follow */
270 break;
271
272 case EAP_TYPE_AKA:
273 case EAP_TYPE_SIM:
274 printf(" subtype [%s] 0x%02x,",
275 tok2str(eap_aka_subtype_values, "unknown", *(tptr+5)),
276 *(tptr+5));
277
278 /* FIXME - TLV attributes follow */
279 break;
280
281 case EAP_TYPE_MD5_CHALLENGE:
282 case EAP_TYPE_OTP:
283 case EAP_TYPE_GTC:
284 case EAP_TYPE_EXPANDED_TYPES:
285 case EAP_TYPE_EXPERIMENTAL:
286 default:
287 break;
288 }
289 }
290 break;
291
292 case EAP_FRAME_TYPE_LOGOFF:
293 case EAP_FRAME_TYPE_ENCAP_ASF_ALERT:
294 default:
295 break;
296 }
297 return;
298
299 trunc:
300 printf("\n\t[|EAP]");
301 }
302
303 /*
304 * Local Variables:
305 * c-basic-offset: 4
306 * End:
307 */
308