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 1.30 1999-12-22 06:27:21 itojun Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <sys/param.h>
  32 #include <sys/time.h>
  33 #include <sys/socket.h>
  34 #include <sys/file.h>
  35 #include <sys/ioctl.h>
  36
  37 #if __STDC__
  38 struct mbuf;
  39 struct rtentry;
  40 #endif
  41 #include <net/if.h>
  42
  43 #include <netinet/in.h>
  44 #include <netinet/in_systm.h>
  45 #include <netinet/ip.h>
  46 #include <netinet/if_ether.h>
  47 #include <netinet/ip_var.h>
  48 #include <netinet/udp.h>
  49 #include <netinet/udp_var.h>
  50 #include <netinet/tcp.h>
  51
  52 #include <pcap.h>
  53 #include <stdio.h>
  54 #include <string.h>
  55
  56 #ifdef INET6
  57 #include <netinet/ip6.h>
  58 #endif
  59
  60 #include "interface.h"
  61 #include "addrtoname.h"
  62
  63 #ifndef AF_NS
  64 #define AF_NS           6               /* XEROX NS protocols */
  65 #endif
  66
  67 /*
  68  * The DLT_NULL packet header is 4 bytes long. It contains a network
  69  * order 32 bit integer that specifies the family, e.g. AF_INET
  70  */
  71 #define NULL_HDRLEN 4
  72
  73 static void
  74 null_print(const u_char *p, const struct ip *ip, u_int length)
  75 {
  76         u_int family;
  77
  78         memcpy((char *)&family, (char *)p, sizeof(family));
  79
  80         if (nflag) {
  81                 /* XXX just dump the header */
  82                 return;
  83         }
  84         switch (family) {
  85
  86         case AF_INET:
  87                 printf("ip: ");
  88                 break;
  89
  90 #ifdef INET6
  91         case AF_INET6:
  92                 printf("ip6: ");
  93                 break;
  94 #endif
  95
  96         case AF_NS:
  97                 printf("ns: ");
  98                 break;
  99
 100         default:
 101                 printf("AF %d: ", family);
 102                 break;
 103         }
 104 }
 105
 106 void
 107 null_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 108 {
 109         u_int length = h->len;
 110         u_int caplen = h->caplen;
 111         const struct ip *ip;
 112
 113         ts_print(&h->ts);
 114
 115         /*
 116          * Some printers want to get back at the link level addresses,
 117          * and/or check that they're not walking off the end of the packet.
 118          * Rather than pass them all the way down, we set these globals.
 119          */
 120         packetp = p;
 121         snapend = p + caplen;
 122
 123         length -= NULL_HDRLEN;
 124
 125         ip = (struct ip *)(p + NULL_HDRLEN);
 126
 127         if (eflag)
 128                 null_print(p, ip, length);
 129
 130         switch (ip->ip_v) {
 131         case 4:
 132                 ip_print((const u_char *)ip, length);
 133                 break;
 134 #ifdef INET6
 135         case 6:
 136                 ip6_print((const u_char *)ip, length);
 137                 break;
 138 #endif /* INET6 */
 139         default:
 140                 printf("ip v%d", ip->ip_v);
 141                 break;
 142         }
 143
 144         if (xflag)
 145                 default_print((const u_char *)ip, caplen - NULL_HDRLEN);
 146         putchar('\n');
 147 }
 148