The Tcpdump Group git mirrors - tcpdump/blob - print-egp.c

   1 /*
   2  * Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms are permitted
   6  * provided that the above copyright notice and this paragraph are
   7  * duplicated in all such forms and that any documentation,
   8  * advertising materials, and other materials related to such
   9  * distribution and use acknowledge that the software was developed
  10  * by the University of California, Lawrence Berkeley Laboratory,
  11  * Berkeley, CA.  The name of the University may not be used to
  12  * endorse or promote products derived from this software without
  13  * specific prior written permission.
  14  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  17  *
  18  * Initial contribution from Jeff Honig (jch@MITCHELL.CIT.CORNELL.EDU).
  19  */
  20
  21 #define NETDISSECT_REWORKED
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include <tcpdump-stdinc.h>
  27
  28 #include "interface.h"
  29 #include "addrtoname.h"
  30 #include "extract.h"
  31
  32 struct egp_packet {
  33         uint8_t  egp_version;
  34 #define EGP_VERSION     2
  35         uint8_t  egp_type;
  36 #define  EGPT_ACQUIRE   3
  37 #define  EGPT_REACH     5
  38 #define  EGPT_POLL      2
  39 #define  EGPT_UPDATE    1
  40 #define  EGPT_ERROR     8
  41         uint8_t  egp_code;
  42 #define  EGPC_REQUEST   0
  43 #define  EGPC_CONFIRM   1
  44 #define  EGPC_REFUSE    2
  45 #define  EGPC_CEASE     3
  46 #define  EGPC_CEASEACK  4
  47 #define  EGPC_HELLO     0
  48 #define  EGPC_HEARDU    1
  49         uint8_t  egp_status;
  50 #define  EGPS_UNSPEC    0
  51 #define  EGPS_ACTIVE    1
  52 #define  EGPS_PASSIVE   2
  53 #define  EGPS_NORES     3
  54 #define  EGPS_ADMIN     4
  55 #define  EGPS_GODOWN    5
  56 #define  EGPS_PARAM     6
  57 #define  EGPS_PROTO     7
  58 #define  EGPS_INDET     0
  59 #define  EGPS_UP        1
  60 #define  EGPS_DOWN      2
  61 #define  EGPS_UNSOL     0x80
  62         uint16_t  egp_checksum;
  63         uint16_t  egp_as;
  64         uint16_t  egp_sequence;
  65         union {
  66                 uint16_t  egpu_hello;
  67                 uint8_t egpu_gws[2];
  68                 uint16_t  egpu_reason;
  69 #define  EGPR_UNSPEC    0
  70 #define  EGPR_BADHEAD   1
  71 #define  EGPR_BADDATA   2
  72 #define  EGPR_NOREACH   3
  73 #define  EGPR_XSPOLL    4
  74 #define  EGPR_NORESP    5
  75 #define  EGPR_UVERSION  6
  76         } egp_handg;
  77 #define  egp_hello  egp_handg.egpu_hello
  78 #define  egp_intgw  egp_handg.egpu_gws[0]
  79 #define  egp_extgw  egp_handg.egpu_gws[1]
  80 #define  egp_reason  egp_handg.egpu_reason
  81         union {
  82                 uint16_t  egpu_poll;
  83                 uint32_t egpu_sourcenet;
  84         } egp_pands;
  85 #define  egp_poll  egp_pands.egpu_poll
  86 #define  egp_sourcenet  egp_pands.egpu_sourcenet
  87 };
  88
  89 static const char *egp_acquire_codes[] = {
  90         "request",
  91         "confirm",
  92         "refuse",
  93         "cease",
  94         "cease_ack"
  95 };
  96
  97 static const char *egp_acquire_status[] = {
  98         "unspecified",
  99         "active_mode",
 100         "passive_mode",
 101         "insufficient_resources",
 102         "administratively_prohibited",
 103         "going_down",
 104         "parameter_violation",
 105         "protocol_violation"
 106 };
 107
 108 static const char *egp_reach_codes[] = {
 109         "hello",
 110         "i-h-u"
 111 };
 112
 113 static const char *egp_status_updown[] = {
 114         "indeterminate",
 115         "up",
 116         "down"
 117 };
 118
 119 static const char *egp_reasons[] = {
 120         "unspecified",
 121         "bad_EGP_header_format",
 122         "bad_EGP_data_field_format",
 123         "reachability_info_unavailable",
 124         "excessive_polling_rate",
 125         "no_response",
 126         "unsupported_version"
 127 };
 128
 129 static void
 130 egpnrprint(netdissect_options *ndo,
 131            register const struct egp_packet *egp)
 132 {
 133         register const uint8_t *cp;
 134         uint32_t addr;
 135         register uint32_t net;
 136         register u_int netlen;
 137         int gateways, distances, networks;
 138         int t_gateways;
 139         const char *comma;
 140
 141         addr = egp->egp_sourcenet;
 142         if (IN_CLASSA(addr)) {
 143                 net = addr & IN_CLASSA_NET;
 144                 netlen = 1;
 145         } else if (IN_CLASSB(addr)) {
 146                 net = addr & IN_CLASSB_NET;
 147                 netlen = 2;
 148         } else if (IN_CLASSC(addr)) {
 149                 net = addr & IN_CLASSC_NET;
 150                 netlen = 3;
 151         } else {
 152                 net = 0;
 153                 netlen = 0;
 154         }
 155         cp = (uint8_t *)(egp + 1);
 156
 157         t_gateways = egp->egp_intgw + egp->egp_extgw;
 158         for (gateways = 0; gateways < t_gateways; ++gateways) {
 159                 /* Pickup host part of gateway address */
 160                 addr = 0;
 161                 ND_TCHECK2(cp[0], 4 - netlen);
 162                 switch (netlen) {
 163
 164                 case 1:
 165                         addr = *cp++;
 166                         /* fall through */
 167                 case 2:
 168                         addr = (addr << 8) | *cp++;
 169                         /* fall through */
 170                 case 3:
 171                         addr = (addr << 8) | *cp++;
 172                 }
 173                 addr |= net;
 174                 ND_TCHECK2(cp[0], 1);
 175                 distances = *cp++;
 176                 ND_PRINT((ndo, " %s %s ",
 177                        gateways < (int)egp->egp_intgw ? "int" : "ext",
 178                        ipaddr_string(ndo, &addr)));
 179
 180                 comma = "";
 181                 ND_PRINT((ndo, "("));
 182                 while (--distances >= 0) {
 183                         ND_TCHECK2(cp[0], 2);
 184                         ND_PRINT((ndo, "%sd%d:", comma, (int)*cp++));
 185                         comma = ", ";
 186                         networks = *cp++;
 187                         while (--networks >= 0) {
 188                                 /* Pickup network number */
 189                                 ND_TCHECK2(cp[0], 1);
 190                                 addr = (uint32_t)*cp++ << 24;
 191                                 if (IN_CLASSB(addr)) {
 192                                         ND_TCHECK2(cp[0], 1);
 193                                         addr |= (uint32_t)*cp++ << 16;
 194                                 } else if (!IN_CLASSA(addr)) {
 195                                         ND_TCHECK2(cp[0], 2);
 196                                         addr |= (uint32_t)*cp++ << 16;
 197                                         addr |= (uint32_t)*cp++ << 8;
 198                                 }
 199                                 ND_PRINT((ndo, " %s", ipaddr_string(ndo, &addr)));
 200                         }
 201                 }
 202                 ND_PRINT((ndo, ")"));
 203         }
 204         return;
 205 trunc:
 206         ND_PRINT((ndo, "[|]"));
 207 }
 208
 209 void
 210 egp_print(netdissect_options *ndo,
 211           register const uint8_t *bp, register u_int length)
 212 {
 213         register const struct egp_packet *egp;
 214         register int status;
 215         register int code;
 216         register int type;
 217
 218         egp = (struct egp_packet *)bp;
 219         if (!ND_TTEST2(*egp, length)) {
 220                 ND_PRINT((ndo, "[|egp]"));
 221                 return;
 222         }
 223
 224         if (!ndo->ndo_vflag) {
 225             ND_PRINT((ndo, "EGPv%u, AS %u, seq %u, length %u",
 226                    egp->egp_version,
 227                    EXTRACT_16BITS(&egp->egp_as),
 228                    EXTRACT_16BITS(&egp->egp_sequence),
 229                    length));
 230             return;
 231         } else
 232             ND_PRINT((ndo, "EGPv%u, length %u",
 233                    egp->egp_version,
 234                    length));
 235
 236         if (egp->egp_version != EGP_VERSION) {
 237                 ND_PRINT((ndo, "[version %d]", egp->egp_version));
 238                 return;
 239         }
 240
 241         type = egp->egp_type;
 242         code = egp->egp_code;
 243         status = egp->egp_status;
 244
 245         switch (type) {
 246         case EGPT_ACQUIRE:
 247                 ND_PRINT((ndo, " acquire"));
 248                 switch (code) {
 249                 case EGPC_REQUEST:
 250                 case EGPC_CONFIRM:
 251                         ND_PRINT((ndo, " %s", egp_acquire_codes[code]));
 252                         switch (status) {
 253                         case EGPS_UNSPEC:
 254                         case EGPS_ACTIVE:
 255                         case EGPS_PASSIVE:
 256                                 ND_PRINT((ndo, " %s", egp_acquire_status[status]));
 257                                 break;
 258
 259                         default:
 260                                 ND_PRINT((ndo, " [status %d]", status));
 261                                 break;
 262                         }
 263                         ND_PRINT((ndo, " hello:%d poll:%d",
 264                                EXTRACT_16BITS(&egp->egp_hello),
 265                                EXTRACT_16BITS(&egp->egp_poll)));
 266                         break;
 267
 268                 case EGPC_REFUSE:
 269                 case EGPC_CEASE:
 270                 case EGPC_CEASEACK:
 271                         ND_PRINT((ndo, " %s", egp_acquire_codes[code]));
 272                         switch (status ) {
 273                         case EGPS_UNSPEC:
 274                         case EGPS_NORES:
 275                         case EGPS_ADMIN:
 276                         case EGPS_GODOWN:
 277                         case EGPS_PARAM:
 278                         case EGPS_PROTO:
 279                                 ND_PRINT((ndo, " %s", egp_acquire_status[status]));
 280                                 break;
 281
 282                         default:
 283                                 ND_PRINT((ndo, "[status %d]", status));
 284                                 break;
 285                         }
 286                         break;
 287
 288                 default:
 289                         ND_PRINT((ndo, "[code %d]", code));
 290                         break;
 291                 }
 292                 break;
 293
 294         case EGPT_REACH:
 295                 switch (code) {
 296
 297                 case EGPC_HELLO:
 298                 case EGPC_HEARDU:
 299                         ND_PRINT((ndo, " %s", egp_reach_codes[code]));
 300                         if (status <= EGPS_DOWN)
 301                                 ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 302                         else
 303                                 ND_PRINT((ndo, " [status %d]", status));
 304                         break;
 305
 306                 default:
 307                         ND_PRINT((ndo, "[reach code %d]", code));
 308                         break;
 309                 }
 310                 break;
 311
 312         case EGPT_POLL:
 313                 ND_PRINT((ndo, " poll"));
 314                 if (egp->egp_status <= EGPS_DOWN)
 315                         ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 316                 else
 317                         ND_PRINT((ndo, " [status %d]", status));
 318                 ND_PRINT((ndo, " net:%s", ipaddr_string(ndo, &egp->egp_sourcenet)));
 319                 break;
 320
 321         case EGPT_UPDATE:
 322                 ND_PRINT((ndo, " update"));
 323                 if (status & EGPS_UNSOL) {
 324                         status &= ~EGPS_UNSOL;
 325                         ND_PRINT((ndo, " unsolicited"));
 326                 }
 327                 if (status <= EGPS_DOWN)
 328                         ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 329                 else
 330                         ND_PRINT((ndo, " [status %d]", status));
 331                 ND_PRINT((ndo, " %s int %d ext %d",
 332                        ipaddr_string(ndo, &egp->egp_sourcenet),
 333                        egp->egp_intgw,
 334                        egp->egp_extgw));
 335                 if (ndo->ndo_vflag)
 336                         egpnrprint(ndo, egp);
 337                 break;
 338
 339         case EGPT_ERROR:
 340                 ND_PRINT((ndo, " error"));
 341                 if (status <= EGPS_DOWN)
 342                         ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
 343                 else
 344                         ND_PRINT((ndo, " [status %d]", status));
 345
 346                 if (EXTRACT_16BITS(&egp->egp_reason) <= EGPR_UVERSION)
 347                         ND_PRINT((ndo, " %s", egp_reasons[EXTRACT_16BITS(&egp->egp_reason)]));
 348                 else
 349                         ND_PRINT((ndo, " [reason %d]", EXTRACT_16BITS(&egp->egp_reason)));
 350                 break;
 351
 352         default:
 353                 ND_PRINT((ndo, "[type %d]", type));
 354                 break;
 355         }
 356 }