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/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may 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.
*
* $FreeBSD$
*/
#ifndef lint
static const char rcsid[] =
"@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.61 2000/12/22 22:45:10 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
struct mbuf;
struct rtentry;
#include <netinet/in.h>
#include <stdio.h>
#include <pcap.h>
#include "interface.h"
#include "addrtoname.h"
#include "ethertype.h"
#include "ether.h"
const u_char *packetp;
const u_char *snapend;
static inline void
ether_print(register const u_char *bp, u_int length)
{
register const struct ether_header *ep;
ep = (const struct ether_header *)bp;
if (qflag)
(void)printf("%s %s %d: ",
etheraddr_string(ESRC(ep)),
etheraddr_string(EDST(ep)),
length);
else
(void)printf("%s %s %s %d: ",
etheraddr_string(ESRC(ep)),
etheraddr_string(EDST(ep)),
etherproto_string(ep->ether_type),
length);
}
/*
* This is the top level routine of the printer. 'p' is the points
* to the ether header of the packet, 'h->tv' is the timestamp,
* 'h->length' is the length of the packet off the wire, and 'h->caplen'
* is the number of bytes actually captured.
*/
void
ether_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
{
u_int caplen = h->caplen;
u_int length = h->len;
struct ether_header *ep;
u_short ether_type;
u_short extracted_ethertype;
ts_print(&h->ts);
if (caplen < ETHER_HDRLEN) {
printf("[|ether]");
goto out;
}
if (eflag)
ether_print(p, length);
/*
* Some printers want to get back at the ethernet addresses,
* and/or check that they're not walking off the end of the packet.
* Rather than pass them all the way down, we set these globals.
*/
packetp = p;
snapend = p + caplen;
length -= ETHER_HDRLEN;
caplen -= ETHER_HDRLEN;
ep = (struct ether_header *)p;
p += ETHER_HDRLEN;
ether_type = ntohs(ep->ether_type);
/*
* Is it (gag) an 802.3 encapsulation?
*/
extracted_ethertype = 0;
if (ether_type <= ETHERMTU) {
/* Try to print the LLC-layer header & higher layers */
if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
&extracted_ethertype) == 0) {
/* ether_type not known, print raw packet */
if (!eflag)
ether_print((u_char *)ep, length + ETHER_HDRLEN);
if (extracted_ethertype) {
printf("(LLC %s) ",
etherproto_string(htons(extracted_ethertype)));
}
if (!xflag && !qflag)
default_print(p, caplen);
}
} else if (ether_encap_print(ether_type, p, length, caplen,
&extracted_ethertype) == 0) {
/* ether_type not known, print raw packet */
if (!eflag)
ether_print((u_char *)ep, length + ETHER_HDRLEN);
if (!xflag && !qflag)
default_print(p, caplen);
}
if (xflag)
default_print(p, caplen);
out:
putchar('\n');
}
/*
* Prints the packet encapsulated in an Ethernet data segment
* (or an equivalent encapsulation), given the Ethernet type code.
*
* Returns non-zero if it can do so, zero if the ethertype is unknown.
*
* The Ethernet type code is passed through a pointer; if it was
* ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
* the 802.1Q payload, for the benefit of lower layers that might
* want to know what it is.
*/
int
ether_encap_print(u_short ethertype, const u_char *p,
u_int length, u_int caplen, u_short *extracted_ethertype)
{
recurse:
*extracted_ethertype = ethertype;
switch (ethertype) {
case ETHERTYPE_IP:
ip_print(p, length);
return (1);
#ifdef INET6
case ETHERTYPE_IPV6:
ip6_print(p, length);
return (1);
#endif /*INET6*/
case ETHERTYPE_ARP:
case ETHERTYPE_REVARP:
arp_print(p, length, caplen);
return (1);
case ETHERTYPE_DN:
decnet_print(p, length, caplen);
return (1);
case ETHERTYPE_ATALK:
if (vflag)
fputs("et1 ", stdout);
atalk_print(p, length);
return (1);
case ETHERTYPE_AARP:
aarp_print(p, length);
return (1);
case ETHERTYPE_IPX:
ipx_print(p, length);
return (1);
case ETHERTYPE_8021Q:
printf("802.1Q vlan#%d P%d%s ",
ntohs(*(u_int16_t *)p) & 0xfff,
ntohs(*(u_int16_t *)p) >> 13,
(ntohs(*(u_int16_t *)p) & 0x1000) ? " CFI" : "");
ethertype = ntohs(*(u_int16_t *)(p + 2));
p += 4;
length -= 4;
caplen -= 4;
if (ethertype > ETHERMTU)
goto recurse;
*extracted_ethertype = 0;
if (llc_print(p, length, caplen, p - 18, p - 12,
extracted_ethertype) == 0) {
/* ether_type not known, print raw packet */
if (!eflag)
ether_print(p - 18, length + 4);
if (*extracted_ethertype) {
printf("(LLC %s) ",
etherproto_string(htons(*extracted_ethertype)));
}
if (!xflag && !qflag)
default_print(p - 18, caplen + 4);
}
return (1);
case ETHERTYPE_PPPOED:
case ETHERTYPE_PPPOES:
pppoe_print(p, length);
return (1);
case ETHERTYPE_LAT:
case ETHERTYPE_SCA:
case ETHERTYPE_MOPRC:
case ETHERTYPE_MOPDL:
/* default_print for now */
default:
return (0);
}
}
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