xref: /freebsd/contrib/tcpdump/print-eap.c (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
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
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