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/****************************************************************************
** File: slip.c
**
** Author: Michael S. Borella
**
** Comments: Dump slip packets
**
*****************************************************************************/
#include <stdio.h>
#include <pcap.h>
#include <unistd.h>
#include "config.h"
#define SLIP_HDRLEN 16
u_char *packet_ptr;
u_char *packet_end;
/*----------------------------------------------------------------------------
**
** dump_slip()
**
** Process packets from the DLT_RAW interface type
**
**----------------------------------------------------------------------------
*/
void dump_slip(u_char *user, const struct pcap_pkthdr *h, u_char *p)
{
u_int length;
u_int caplen;
struct ip *ip;
void dump_ip(u_char *, u_int);
/*
* Get total packet length and length of the captured section
*/
length = h->len;
caplen = h->caplen;
/*
* Dump raw header
*/
printf("==========================================================\n");
printf(" Slip Header (%u.%06u)\n",
(u_int32_t) h->ts.tv_sec, (u_int32_t) h->ts.tv_usec);
/*
* Check for a truncated packet
*/
if (caplen < SLIP_HDRLEN)
{
printf("Truncated slip header\n");
return;
}
/*
* Some printers want to get back at the link level 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.
*/
packet_ptr = p;
packet_end = p + caplen;
/*
* Calculate length of IP header on out
*/
length -= SLIP_HDRLEN;
/*
* XXX write something to dump SLIP fields here!
*/
ip = (struct ip *) (p + SLIP_HDRLEN);
dump_ip((u_char *) ip, length);
}
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