contrib/tcpdump/print-chdlc.c

   1 /* maybe it should be merged into print-ppp.c */
   2 /*
   3  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that: (1) source code distributions
   8  * retain the above copyright notice and this paragraph in its entirety, (2)
   9  * distributions including binary code include the above copyright notice and
  10  * this paragraph in its entirety in the documentation or other materials
  11  * provided with the distribution, and (3) all advertising materials mentioning
  12  * features or use of this software display the following acknowledgement:
  13  * ``This product includes software developed by the University of California,
  14  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  15  * the University nor the names of its contributors may be used to endorse
  16  * or promote products derived from this software without specific prior
  17  * written permission.
  18  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  19  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  20  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  21  */
  22
  23 #ifndef lint
  24 static const char rcsid[] =
  25     "@(#) $Header: /tcpdump/master/tcpdump/print-chdlc.c,v 1.11 2000/10/09 01:53:19 guy Exp $ (LBL)";
  26 #endif
  27
  28 #ifdef HAVE_CONFIG_H
  29 #include "config.h"
  30 #endif
  31
  32 #include <sys/param.h>
  33 #include <sys/time.h>
  34
  35 #include <netinet/in.h>
  36
  37 #include <ctype.h>
  38 #include <netdb.h>
  39 #include <pcap.h>
  40 #include <stdio.h>
  41
  42 #include "interface.h"
  43 #include "addrtoname.h"
  44 #include "ethertype.h"
  45 #include "ppp.h"
  46 #include "chdlc.h"
  47
  48 static void chdlc_slarp_print(const u_char *, u_int);
  49
  50 /* Standard CHDLC printer */
  51 void
  52 chdlc_if_print(u_char *user, const struct pcap_pkthdr *h,
  53              register const u_char *p)
  54 {
  55         register u_int length = h->len;
  56         register u_int caplen = h->caplen;
  57         const struct ip *ip;
  58         u_int proto;
  59
  60         ts_print(&h->ts);
  61
  62         if (caplen < CHDLC_HDRLEN) {
  63                 printf("[|chdlc]");
  64                 goto out;
  65         }
  66
  67         /*
  68          * Some printers want to get back at the link level addresses,
  69          * and/or check that they're not walking off the end of the packet.
  70          * Rather than pass them all the way down, we set these globals.
  71          */
  72         proto = ntohs(*(u_short *)&p[2]);
  73         packetp = p;
  74         snapend = p + caplen;
  75
  76         if (eflag) {
  77                 switch (p[0]) {
  78                 case CHDLC_UNICAST:
  79                         printf("unicast ");
  80                         break;
  81                 case CHDLC_BCAST:
  82                         printf("bcast ");
  83                         break;
  84                 default:
  85                         printf("0x%02x ", p[0]);
  86                         break;
  87                 }
  88                 printf("%d %04x: ", length, proto);
  89         }
  90
  91         length -= CHDLC_HDRLEN;
  92         ip = (struct ip *)(p + CHDLC_HDRLEN);
  93         switch (proto) {
  94         case ETHERTYPE_IP:
  95                 ip_print((const u_char *)ip, length);
  96                 break;
  97 #ifdef INET6
  98         case ETHERTYPE_IPV6:
  99                 ip6_print((const u_char *)ip, length);
 100                 break;
 101 #endif
 102         case CHDLC_TYPE_SLARP:
 103                 chdlc_slarp_print((const u_char *)ip, length);
 104                 break;
 105 #if 0
 106         case CHDLC_TYPE_CDP:
 107                 chdlc_cdp_print((const u_char *)ip, length);
 108                 break;
 109 #endif
 110         }
 111         if (xflag)
 112                 default_print((const u_char *)ip, caplen - CHDLC_HDRLEN);
 113 out:
 114         putchar('\n');
 115 }
 116
 117 struct cisco_slarp {
 118         u_int32_t code;
 119 #define SLARP_REQUEST   0
 120 #define SLARP_REPLY     1
 121 #define SLARP_KEEPALIVE 2
 122         union {
 123                 struct {
 124                         struct in_addr addr;
 125                         struct in_addr mask;
 126                         u_int16_t unused[3];
 127                 } addr;
 128                 struct {
 129                         u_int32_t myseq;
 130                         u_int32_t yourseq;
 131                         u_int16_t rel;
 132                         u_int16_t t1;
 133                         u_int16_t t2;
 134                 } keep;
 135         } un;
 136 };
 137
 138 #define SLARP_LEN       18
 139
 140 static void
 141 chdlc_slarp_print(const u_char *cp, u_int length)
 142 {
 143         struct cisco_slarp *slarp;
 144
 145         if (length < SLARP_LEN) {
 146                 printf("[|slarp]");
 147                 return;
 148         }
 149
 150         slarp = (struct cisco_slarp *)cp;
 151         switch (ntohl(slarp->code)) {
 152         case SLARP_REQUEST:
 153                 printf("slarp-request");
 154                 break;
 155         case SLARP_REPLY:
 156                 printf("slarp-reply %s/%s",
 157                         ipaddr_string(&slarp->un.addr.addr),
 158                         ipaddr_string(&slarp->un.addr.mask));
 159                 break;
 160         case SLARP_KEEPALIVE:
 161                 printf("slarp-keepalive my=0x%x your=0x%x ",
 162                         (u_int32_t)ntohl(slarp->un.keep.myseq),
 163                         (u_int32_t)ntohl(slarp->un.keep.yourseq));
 164                 printf("reliability=0x%04x t1=%d.%d",
 165                         ntohs(slarp->un.keep.rel), ntohs(slarp->un.keep.t1),
 166                         ntohs(slarp->un.keep.t2));
 167                 break;
 168         default:
 169                 printf("slarp-0x%x unknown", (u_int32_t)ntohl(slarp->code));
 170                 break;
 171         }
 172
 173         if (SLARP_LEN < length && vflag)
 174                 printf("(trailing junk: %d bytes)", length - SLARP_LEN);
 175 }