Home | History | Annotate | Download | only in tcpdump
      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 (at) 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 }
    357