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

   1 /*
   2  * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #ifndef lint
  23 static const char rcsid[] =
  24     "@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.24 1999-10-07 23:47:12 mcr Exp $ (LBL)";
  25 #endif
  26
  27 #include <sys/param.h>
  28 #include <sys/time.h>
  29 #include <sys/socket.h>
  30 #include <sys/file.h>
  31 #include <sys/ioctl.h>
  32
  33 #if __STDC__
  34 struct mbuf;
  35 struct rtentry;
  36 #endif
  37 #include <net/if.h>
  38
  39 #include <netinet/in.h>
  40 #include <netinet/in_systm.h>
  41 #include <netinet/ip.h>
  42 #include <netinet/if_ether.h>
  43 #include <netinet/ip_var.h>
  44 #include <netinet/udp.h>
  45 #include <netinet/udp_var.h>
  46 #include <netinet/tcp.h>
  47 #include <netinet/tcpip.h>
  48
  49 #include <pcap.h>
  50 #include <stdio.h>
  51 #include <string.h>
  52
  53 #include "interface.h"
  54 #include "addrtoname.h"
  55
  56 #ifndef AF_NS
  57 #define AF_NS           6               /* XEROX NS protocols */
  58 #endif
  59
  60 /*
  61  * The DLT_NULL packet header is 4 bytes long. It contains a network
  62  * order 32 bit integer that specifies the family, e.g. AF_INET
  63  */
  64 #define NULL_HDRLEN 4
  65
  66 static void
  67 null_print(const u_char *p, const struct ip *ip, u_int length)
  68 {
  69         u_int family;
  70
  71         memcpy((char *)&family, (char *)p, sizeof(family));
  72
  73         if (nflag) {
  74                 /* XXX just dump the header */
  75                 return;
  76         }
  77         switch (family) {
  78
  79         case AF_INET:
  80                 printf("ip: ");
  81                 break;
  82
  83         case AF_NS:
  84                 printf("ns: ");
  85                 break;
  86
  87         default:
  88                 printf("AF %d: ", family);
  89                 break;
  90         }
  91 }
  92
  93 void
  94 null_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
  95 {
  96         u_int length = h->len;
  97         u_int caplen = h->caplen;
  98         const struct ip *ip;
  99
 100         ts_print(&h->ts);
 101
 102         /*
 103          * Some printers want to get back at the link level addresses,
 104          * and/or check that they're not walking off the end of the packet.
 105          * Rather than pass them all the way down, we set these globals.
 106          */
 107         packetp = p;
 108         snapend = p + caplen;
 109
 110         length -= NULL_HDRLEN;
 111
 112         ip = (struct ip *)(p + NULL_HDRLEN);
 113
 114         if (eflag)
 115                 null_print(p, ip, length);
 116
 117         ip_print((const u_char *)ip, length);
 118
 119         if (xflag)
 120                 default_print((const u_char *)ip, caplen - NULL_HDRLEN);
 121         putchar('\n');
 122 }
 123