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

   1 /*
   2  * Copyright (c) 1990, 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-chdlc.c,v 1.27 2002-12-19 09:39:11 guy Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <tcpdump-stdinc.h>
  32
  33 #include <pcap.h>
  34 #include <stdio.h>
  35
  36 #include "interface.h"
  37 #include "addrtoname.h"
  38 #include "ethertype.h"
  39 #include "extract.h"
  40 #include "ppp.h"
  41 #include "chdlc.h"
  42
  43 static void chdlc_slarp_print(const u_char *, u_int);
  44
  45 /* Standard CHDLC printer */
  46 u_int
  47 chdlc_if_print(const struct pcap_pkthdr *h, register const u_char *p)
  48 {
  49         register u_int length = h->len;
  50         register u_int caplen = h->caplen;
  51         const struct ip *ip;
  52         u_int proto;
  53
  54         if (caplen < CHDLC_HDRLEN) {
  55                 printf("[|chdlc]");
  56                 return (caplen);
  57         }
  58
  59         proto = EXTRACT_16BITS(&p[2]);
  60         if (eflag) {
  61                 switch (p[0]) {
  62                 case CHDLC_UNICAST:
  63                         printf("unicast ");
  64                         break;
  65                 case CHDLC_BCAST:
  66                         printf("bcast ");
  67                         break;
  68                 default:
  69                         printf("0x%02x ", p[0]);
  70                         break;
  71                 }
  72                 printf("%d %04x: ", length, proto);
  73         }
  74
  75         length -= CHDLC_HDRLEN;
  76         ip = (const struct ip *)(p + CHDLC_HDRLEN);
  77         switch (proto) {
  78         case ETHERTYPE_IP:
  79                 ip_print((const u_char *)ip, length);
  80                 break;
  81 #ifdef INET6
  82         case ETHERTYPE_IPV6:
  83                 ip6_print((const u_char *)ip, length);
  84                 break;
  85 #endif
  86         case CHDLC_TYPE_SLARP:
  87                 chdlc_slarp_print((const u_char *)ip, length);
  88                 break;
  89 #if 0
  90         case CHDLC_TYPE_CDP:
  91                 chdlc_cdp_print((const u_char *)ip, length);
  92                 break;
  93 #endif
  94         case ETHERTYPE_MPLS:
  95         case ETHERTYPE_MPLS_MULTI:
  96                 mpls_print((const u_char *)(ip), length);
  97                 break;
  98         case ETHERTYPE_ISO:
  99                 /* is the fudge byte set ? lets verify by spotting ISO headers */
 100                 if (*(p+CHDLC_HDRLEN+1) == 0x81 ||
 101                     *(p+CHDLC_HDRLEN+1) == 0x82 ||
 102                     *(p+CHDLC_HDRLEN+1) == 0x83)
 103                     isoclns_print(p+CHDLC_HDRLEN+1, length-1, length-1, NULL, NULL);
 104                 else
 105                     isoclns_print(p+CHDLC_HDRLEN, length, length, NULL, NULL);
 106                 break;
 107         default:
 108                 printf("unknown CHDLC protocol (0x%04x)", proto);
 109                 break;
 110         }
 111
 112         return (CHDLC_HDRLEN);
 113 }
 114
 115 struct cisco_slarp {
 116         u_int32_t code;
 117 #define SLARP_REQUEST   0
 118 #define SLARP_REPLY     1
 119 #define SLARP_KEEPALIVE 2
 120         union {
 121                 struct {
 122                         struct in_addr addr;
 123                         struct in_addr mask;
 124                         u_int16_t unused[3];
 125                 } addr;
 126                 struct {
 127                         u_int32_t myseq;
 128                         u_int32_t yourseq;
 129                         u_int16_t rel;
 130                         u_int16_t t1;
 131                         u_int16_t t2;
 132                 } keep;
 133         } un;
 134 };
 135
 136 #define SLARP_LEN       18
 137
 138 static void
 139 chdlc_slarp_print(const u_char *cp, u_int length)
 140 {
 141         const struct cisco_slarp *slarp;
 142
 143         if (length < SLARP_LEN) {
 144                 printf("[|slarp]");
 145                 return;
 146         }
 147
 148         slarp = (const struct cisco_slarp *)cp;
 149         printf("SLARP (length: %u), ",length);
 150         switch (EXTRACT_32BITS(&slarp->code)) {
 151         case SLARP_REQUEST:
 152                 printf("request");
 153                 /* ok we do not know it - but lets at least dump it */
 154                 print_unknown_data(cp+4,"\n\t",length-4);
 155                 break;
 156         case SLARP_REPLY:
 157                 printf("reply %s/%s",
 158                         ipaddr_string(&slarp->un.addr.addr),
 159                         ipaddr_string(&slarp->un.addr.mask));
 160                 break;
 161         case SLARP_KEEPALIVE:
 162                 printf("keepalive: mineseen=0x%08x, yourseen=0x%08x",
 163                         EXTRACT_32BITS(&slarp->un.keep.myseq),
 164                         EXTRACT_32BITS(&slarp->un.keep.yourseq));
 165                 printf(", reliability=0x%04x, t1=%d.%d",
 166                         EXTRACT_16BITS(&slarp->un.keep.rel),
 167                         EXTRACT_16BITS(&slarp->un.keep.t1),
 168                         EXTRACT_16BITS(&slarp->un.keep.t2));
 169                 break;
 170         default:
 171                 printf("0x%02x unknown", EXTRACT_32BITS(&slarp->code));
 172                 if (vflag <= 1)
 173                     print_unknown_data(cp+4,"\n\t",length-4);
 174                 break;
 175         }
 176
 177         if (SLARP_LEN < length && vflag)
 178                 printf(", (trailing junk: %d bytes)", length - SLARP_LEN);
 179         if (vflag > 1)
 180             print_unknown_data(cp+4,"\n\t",length-4);
 181 }