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

   1 /*
   2  * Copyright (c) 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 #ifndef lint
  22 static const char rcsid[] =
  23     "@(#) $Header: /tcpdump/master/tcpdump/print-atm.c,v 1.22 2002-04-07 02:54:03 guy Exp $ (LBL)";
  24 #endif
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29
  30 #include <sys/param.h>
  31 #include <sys/time.h>
  32 #include <sys/socket.h>
  33
  34 #include <netinet/in.h>
  35
  36 #include <stdio.h>
  37 #include <pcap.h>
  38 #include <string.h>
  39
  40 #include "interface.h"
  41 #include "addrtoname.h"
  42 #include "ethertype.h"
  43
  44 #include "ether.h"
  45
  46 /*
  47  * Print an RFC 1483 LLC-encapsulated ATM frame.
  48  */
  49 static void
  50 atm_llc_print(const u_char *p, int length, int caplen)
  51 {
  52         struct ether_header ehdr;
  53         u_short ether_type;
  54         u_short extracted_ethertype;
  55
  56         ether_type = p[6] << 8 | p[7];
  57
  58         /*
  59          * Fake up an Ethernet header for the benefit of printers that
  60          * insist on "packetp" pointing to an Ethernet header.
  61          */
  62         memset(&ehdr, '\0', sizeof ehdr);
  63
  64         /*
  65          * Some printers want to get back at the ethernet addresses,
  66          * and/or check that they're not walking off the end of the packet.
  67          * Rather than pass them all the way down, we set these globals.
  68          */
  69         snapend = p + caplen;
  70         /*
  71          * Actually, the only printers that use packetp are print-arp.c
  72          * and print-bootp.c, and they assume that packetp points to an
  73          * Ethernet header.  The right thing to do is to fix them to know
  74          * which link type is in use when they excavate. XXX
  75          */
  76         packetp = (u_char *)&ehdr;
  77
  78         if (!llc_print(p, length, caplen, ESRC(&ehdr), EDST(&ehdr),
  79             &extracted_ethertype)) {
  80                 /* ether_type not known, print raw packet */
  81                 if (extracted_ethertype) {
  82                         printf("(LLC %s) ",
  83                 etherproto_string(htons(extracted_ethertype)));
  84                 }
  85                 if (!xflag && !qflag)
  86                         default_print(p, caplen);
  87         }
  88 }
  89
  90 /*
  91  * This is the top level routine of the printer.  'p' is the points
  92  * to the LLC/SNAP header of the packet, 'tvp' is the timestamp,
  93  * 'length' is the length of the packet off the wire, and 'caplen'
  94  * is the number of bytes actually captured.
  95  */
  96 void
  97 atm_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
  98 {
  99         u_int caplen = h->caplen;
 100         u_int length = h->len;
 101
 102         ++infodelay;
 103         ts_print(&h->ts);
 104
 105         if (caplen < 8) {
 106                 printf("[|atm]");
 107                 goto out;
 108         }
 109         if (p[0] != 0xaa || p[1] != 0xaa || p[2] != 0x03) {
 110                 /*XXX assume 802.6 MAC header from fore driver */
 111                 if (eflag)
 112                         printf("%04x%04x %04x%04x ",
 113                                p[0] << 24 | p[1] << 16 | p[2] << 8 | p[3],
 114                                p[4] << 24 | p[5] << 16 | p[6] << 8 | p[7],
 115                                p[8] << 24 | p[9] << 16 | p[10] << 8 | p[11],
 116                                p[12] << 24 | p[13] << 16 | p[14] << 8 | p[15]);
 117                 p += 20;
 118                 length -= 20;
 119                 caplen -= 20;
 120         }
 121         atm_llc_print(p, length, caplen);
 122         if (xflag)
 123                 default_print(p, caplen);
 124  out:
 125         putchar('\n');
 126         --infodelay;
 127         if (infoprint)
 128                 info(0);
 129 }