The Tcpdump Group git mirrors - tcpdump/blob - 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 1.13 2001-09-17 21:57:57 fenner 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 "extract.h"
  46 #include "ppp.h"
  47 #include "chdlc.h"
  48
  49 static void chdlc_slarp_print(const u_char *, u_int);
  50
  51 /* Standard CHDLC printer */
  52 void
  53 chdlc_if_print(u_char *user, const struct pcap_pkthdr *h,
  54              register const u_char *p)
  55 {
  56         register u_int length = h->len;
  57         register u_int caplen = h->caplen;
  58
  59         ++infodelay;
  60         ts_print(&h->ts);
  61
  62         /*
  63          * Some printers want to get back at the link level addresses,
  64          * and/or check that they're not walking off the end of the packet.
  65          * Rather than pass them all the way down, we set these globals.
  66          */
  67         packetp = p;
  68         snapend = p + caplen;
  69
  70         chdlc_print(p, length, caplen);
  71
  72         putchar('\n');
  73         --infodelay;
  74         if (infoprint)
  75                 info(0);
  76 }
  77
  78 void
  79 chdlc_print(register const u_char *p, u_int length, u_int caplen)
  80 {
  81         const struct ip *ip;
  82         u_int proto;
  83
  84         if (caplen < CHDLC_HDRLEN) {
  85                 printf("[|chdlc]");
  86                 return;
  87         }
  88
  89         proto = EXTRACT_16BITS(&p[2]);
  90         if (eflag) {
  91                 switch (p[0]) {
  92                 case CHDLC_UNICAST:
  93                         printf("unicast ");
  94                         break;
  95                 case CHDLC_BCAST:
  96                         printf("bcast ");
  97                         break;
  98                 default:
  99                         printf("0x%02x ", p[0]);
 100                         break;
 101                 }
 102                 printf("%d %04x: ", length, proto);
 103         }
 104
 105         length -= CHDLC_HDRLEN;
 106         ip = (const struct ip *)(p + CHDLC_HDRLEN);
 107         switch (proto) {
 108         case ETHERTYPE_IP:
 109                 ip_print((const u_char *)ip, length);
 110                 break;
 111 #ifdef INET6
 112         case ETHERTYPE_IPV6:
 113                 ip6_print((const u_char *)ip, length);
 114                 break;
 115 #endif
 116         case CHDLC_TYPE_SLARP:
 117                 chdlc_slarp_print((const u_char *)ip, length);
 118                 break;
 119 #if 0
 120         case CHDLC_TYPE_CDP:
 121                 chdlc_cdp_print((const u_char *)ip, length);
 122                 break;
 123 #endif
 124         }
 125         if (xflag)
 126                 default_print((const u_char *)ip, caplen - CHDLC_HDRLEN);
 127 }
 128
 129 struct cisco_slarp {
 130         u_int32_t code;
 131 #define SLARP_REQUEST   0
 132 #define SLARP_REPLY     1
 133 #define SLARP_KEEPALIVE 2
 134         union {
 135                 struct {
 136                         struct in_addr addr;
 137                         struct in_addr mask;
 138                         u_int16_t unused[3];
 139                 } addr;
 140                 struct {
 141                         u_int32_t myseq;
 142                         u_int32_t yourseq;
 143                         u_int16_t rel;
 144                         u_int16_t t1;
 145                         u_int16_t t2;
 146                 } keep;
 147         } un;
 148 };
 149
 150 #define SLARP_LEN       18
 151
 152 static void
 153 chdlc_slarp_print(const u_char *cp, u_int length)
 154 {
 155         const struct cisco_slarp *slarp;
 156
 157         if (length < SLARP_LEN) {
 158                 printf("[|slarp]");
 159                 return;
 160         }
 161
 162         slarp = (const struct cisco_slarp *)cp;
 163         switch (ntohl(slarp->code)) {
 164         case SLARP_REQUEST:
 165                 printf("slarp-request");
 166                 break;
 167         case SLARP_REPLY:
 168                 printf("slarp-reply %s/%s",
 169                         ipaddr_string(&slarp->un.addr.addr),
 170                         ipaddr_string(&slarp->un.addr.mask));
 171                 break;
 172         case SLARP_KEEPALIVE:
 173                 printf("slarp-keepalive my=0x%x your=0x%x ",
 174                         (u_int32_t)ntohl(slarp->un.keep.myseq),
 175                         (u_int32_t)ntohl(slarp->un.keep.yourseq));
 176                 printf("reliability=0x%04x t1=%d.%d",
 177                         ntohs(slarp->un.keep.rel), ntohs(slarp->un.keep.t1),
 178                         ntohs(slarp->un.keep.t2));
 179                 break;
 180         default:
 181                 printf("slarp-0x%x unknown", (u_int32_t)ntohl(slarp->code));
 182                 break;
 183         }
 184
 185         if (SLARP_LEN < length && vflag)
 186                 printf("(trailing junk: %d bytes)", length - SLARP_LEN);
 187 }