nexmon – Rev 1
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/*
* Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Lawrence Berkeley Laboratory,
* Berkeley, CA. The name of the University may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Initial contribution from Jeff Honig (jch@MITCHELL.CIT.CORNELL.EDU).
*/
#define NETDISSECT_REWORKED
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include "interface.h"
#include "addrtoname.h"
#include "extract.h"
struct egp_packet {
uint8_t egp_version;
#define EGP_VERSION 2
uint8_t egp_type;
#define EGPT_ACQUIRE 3
#define EGPT_REACH 5
#define EGPT_POLL 2
#define EGPT_UPDATE 1
#define EGPT_ERROR 8
uint8_t egp_code;
#define EGPC_REQUEST 0
#define EGPC_CONFIRM 1
#define EGPC_REFUSE 2
#define EGPC_CEASE 3
#define EGPC_CEASEACK 4
#define EGPC_HELLO 0
#define EGPC_HEARDU 1
uint8_t egp_status;
#define EGPS_UNSPEC 0
#define EGPS_ACTIVE 1
#define EGPS_PASSIVE 2
#define EGPS_NORES 3
#define EGPS_ADMIN 4
#define EGPS_GODOWN 5
#define EGPS_PARAM 6
#define EGPS_PROTO 7
#define EGPS_INDET 0
#define EGPS_UP 1
#define EGPS_DOWN 2
#define EGPS_UNSOL 0x80
uint16_t egp_checksum;
uint16_t egp_as;
uint16_t egp_sequence;
union {
uint16_t egpu_hello;
uint8_t egpu_gws[2];
uint16_t egpu_reason;
#define EGPR_UNSPEC 0
#define EGPR_BADHEAD 1
#define EGPR_BADDATA 2
#define EGPR_NOREACH 3
#define EGPR_XSPOLL 4
#define EGPR_NORESP 5
#define EGPR_UVERSION 6
} egp_handg;
#define egp_hello egp_handg.egpu_hello
#define egp_intgw egp_handg.egpu_gws[0]
#define egp_extgw egp_handg.egpu_gws[1]
#define egp_reason egp_handg.egpu_reason
union {
uint16_t egpu_poll;
uint32_t egpu_sourcenet;
} egp_pands;
#define egp_poll egp_pands.egpu_poll
#define egp_sourcenet egp_pands.egpu_sourcenet
};
static const char *egp_acquire_codes[] = {
"request",
"confirm",
"refuse",
"cease",
"cease_ack"
};
static const char *egp_acquire_status[] = {
"unspecified",
"active_mode",
"passive_mode",
"insufficient_resources",
"administratively_prohibited",
"going_down",
"parameter_violation",
"protocol_violation"
};
static const char *egp_reach_codes[] = {
"hello",
"i-h-u"
};
static const char *egp_status_updown[] = {
"indeterminate",
"up",
"down"
};
static const char *egp_reasons[] = {
"unspecified",
"bad_EGP_header_format",
"bad_EGP_data_field_format",
"reachability_info_unavailable",
"excessive_polling_rate",
"no_response",
"unsupported_version"
};
static void
egpnrprint(netdissect_options *ndo,
register const struct egp_packet *egp)
{
register const uint8_t *cp;
uint32_t addr;
register uint32_t net;
register u_int netlen;
int gateways, distances, networks;
int t_gateways;
const char *comma;
addr = egp->egp_sourcenet;
if (IN_CLASSA(addr)) {
net = addr & IN_CLASSA_NET;
netlen = 1;
} else if (IN_CLASSB(addr)) {
net = addr & IN_CLASSB_NET;
netlen = 2;
} else if (IN_CLASSC(addr)) {
net = addr & IN_CLASSC_NET;
netlen = 3;
} else {
net = 0;
netlen = 0;
}
cp = (uint8_t *)(egp + 1);
t_gateways = egp->egp_intgw + egp->egp_extgw;
for (gateways = 0; gateways < t_gateways; ++gateways) {
/* Pickup host part of gateway address */
addr = 0;
ND_TCHECK2(cp[0], 4 - netlen);
switch (netlen) {
case 1:
addr = *cp++;
/* fall through */
case 2:
addr = (addr << 8) | *cp++;
/* fall through */
case 3:
addr = (addr << 8) | *cp++;
}
addr |= net;
ND_TCHECK2(cp[0], 1);
distances = *cp++;
ND_PRINT((ndo, " %s %s ",
gateways < (int)egp->egp_intgw ? "int" : "ext",
ipaddr_string(ndo, &addr)));
comma = "";
ND_PRINT((ndo, "("));
while (--distances >= 0) {
ND_TCHECK2(cp[0], 2);
ND_PRINT((ndo, "%sd%d:", comma, (int)*cp++));
comma = ", ";
networks = *cp++;
while (--networks >= 0) {
/* Pickup network number */
ND_TCHECK2(cp[0], 1);
addr = (uint32_t)*cp++ << 24;
if (IN_CLASSB(addr)) {
ND_TCHECK2(cp[0], 1);
addr |= (uint32_t)*cp++ << 16;
} else if (!IN_CLASSA(addr)) {
ND_TCHECK2(cp[0], 2);
addr |= (uint32_t)*cp++ << 16;
addr |= (uint32_t)*cp++ << 8;
}
ND_PRINT((ndo, " %s", ipaddr_string(ndo, &addr)));
}
}
ND_PRINT((ndo, ")"));
}
return;
trunc:
ND_PRINT((ndo, "[|]"));
}
void
egp_print(netdissect_options *ndo,
register const uint8_t *bp, register u_int length)
{
register const struct egp_packet *egp;
register int status;
register int code;
register int type;
egp = (struct egp_packet *)bp;
if (!ND_TTEST2(*egp, length)) {
ND_PRINT((ndo, "[|egp]"));
return;
}
if (!ndo->ndo_vflag) {
ND_PRINT((ndo, "EGPv%u, AS %u, seq %u, length %u",
egp->egp_version,
EXTRACT_16BITS(&egp->egp_as),
EXTRACT_16BITS(&egp->egp_sequence),
length));
return;
} else
ND_PRINT((ndo, "EGPv%u, length %u",
egp->egp_version,
length));
if (egp->egp_version != EGP_VERSION) {
ND_PRINT((ndo, "[version %d]", egp->egp_version));
return;
}
type = egp->egp_type;
code = egp->egp_code;
status = egp->egp_status;
switch (type) {
case EGPT_ACQUIRE:
ND_PRINT((ndo, " acquire"));
switch (code) {
case EGPC_REQUEST:
case EGPC_CONFIRM:
ND_PRINT((ndo, " %s", egp_acquire_codes[code]));
switch (status) {
case EGPS_UNSPEC:
case EGPS_ACTIVE:
case EGPS_PASSIVE:
ND_PRINT((ndo, " %s", egp_acquire_status[status]));
break;
default:
ND_PRINT((ndo, " [status %d]", status));
break;
}
ND_PRINT((ndo, " hello:%d poll:%d",
EXTRACT_16BITS(&egp->egp_hello),
EXTRACT_16BITS(&egp->egp_poll)));
break;
case EGPC_REFUSE:
case EGPC_CEASE:
case EGPC_CEASEACK:
ND_PRINT((ndo, " %s", egp_acquire_codes[code]));
switch (status ) {
case EGPS_UNSPEC:
case EGPS_NORES:
case EGPS_ADMIN:
case EGPS_GODOWN:
case EGPS_PARAM:
case EGPS_PROTO:
ND_PRINT((ndo, " %s", egp_acquire_status[status]));
break;
default:
ND_PRINT((ndo, "[status %d]", status));
break;
}
break;
default:
ND_PRINT((ndo, "[code %d]", code));
break;
}
break;
case EGPT_REACH:
switch (code) {
case EGPC_HELLO:
case EGPC_HEARDU:
ND_PRINT((ndo, " %s", egp_reach_codes[code]));
if (status <= EGPS_DOWN)
ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
else
ND_PRINT((ndo, " [status %d]", status));
break;
default:
ND_PRINT((ndo, "[reach code %d]", code));
break;
}
break;
case EGPT_POLL:
ND_PRINT((ndo, " poll"));
if (egp->egp_status <= EGPS_DOWN)
ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
else
ND_PRINT((ndo, " [status %d]", status));
ND_PRINT((ndo, " net:%s", ipaddr_string(ndo, &egp->egp_sourcenet)));
break;
case EGPT_UPDATE:
ND_PRINT((ndo, " update"));
if (status & EGPS_UNSOL) {
status &= ~EGPS_UNSOL;
ND_PRINT((ndo, " unsolicited"));
}
if (status <= EGPS_DOWN)
ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
else
ND_PRINT((ndo, " [status %d]", status));
ND_PRINT((ndo, " %s int %d ext %d",
ipaddr_string(ndo, &egp->egp_sourcenet),
egp->egp_intgw,
egp->egp_extgw));
if (ndo->ndo_vflag)
egpnrprint(ndo, egp);
break;
case EGPT_ERROR:
ND_PRINT((ndo, " error"));
if (status <= EGPS_DOWN)
ND_PRINT((ndo, " state:%s", egp_status_updown[status]));
else
ND_PRINT((ndo, " [status %d]", status));
if (EXTRACT_16BITS(&egp->egp_reason) <= EGPR_UVERSION)
ND_PRINT((ndo, " %s", egp_reasons[EXTRACT_16BITS(&egp->egp_reason)]));
else
ND_PRINT((ndo, " [reason %d]", EXTRACT_16BITS(&egp->egp_reason)));
break;
default:
ND_PRINT((ndo, "[type %d]", type));
break;
}
}