contrib/tcpdump/print-eap.c

   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  */