dist/tcpdump/print-chdlc.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that: (1) source code distributions
   9  * retain the above copyright notice and this paragraph in its entirety, (2)
  10  * distributions including binary code include the above copyright notice and
  11  * this paragraph in its entirety in the documentation or other materials
  12  * provided with the distribution, and (3) all advertising materials mentioning
  13  * features or use of this software display the following acknowledgement:
  14  * ``This product includes software developed by the University of California,
  15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  16  * the University nor the names of its contributors may be used to endorse
  17  * or promote products derived from this software without specific prior
  18  * written permission.
  19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  22  */
  23
  24 #include <sys/cdefs.h>
  25 #ifndef lint
  26 #if 0
  27 static const char rcsid[] _U_ =
  28     "@(#) Header: /tcpdump/master/tcpdump/print-chdlc.c,v 1.32.2.11 2005/11/29 08:57:10 hannes Exp (LBL)";
  29 #else
  30 __RCSID("$NetBSD: tcpdump2rcsid.ex,v 1.1 2001/06/25 20:09:58 itojun Exp $");
  31 #endif
  32 #endif
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include "config.h"
  36 #endif
  37
  38 #include <tcpdump-stdinc.h>
  39
  40 #include <pcap.h>
  41 #include <stdio.h>
  42
  43 #include "interface.h"
  44 #include "addrtoname.h"
  45 #include "ethertype.h"
  46 #include "extract.h"
  47 #include "ppp.h"
  48 #include "chdlc.h"
  49
  50 static void chdlc_slarp_print(const u_char *, u_int);
  51
  52 const struct tok chdlc_cast_values[] = {
  53     { CHDLC_UNICAST, "unicast" },
  54     { CHDLC_BCAST, "bcast" },
  55     { 0, NULL}
  56 };
  57
  58
  59 /* Standard CHDLC printer */
  60 u_int
  61 chdlc_if_print(const struct pcap_pkthdr *h, register const u_char *p)
  62 {
  63         register u_int length = h->len;
  64         register u_int caplen = h->caplen;
  65
  66         if (caplen < CHDLC_HDRLEN) {
  67                 printf("[|chdlc]");
  68                 return (caplen);
  69         }
  70         return (chdlc_print(p,length));
  71 }
  72
  73 u_int
  74 chdlc_print(register const u_char *p, u_int length) {
  75         u_int proto;
  76
  77         proto = EXTRACT_16BITS(&p[2]);
  78         if (eflag) {
  79                 printf("%s, ethertype %s (0x%04x), length %u: ",
  80                        tok2str(chdlc_cast_values, "0x%02x", p[0]),
  81                        tok2str(ethertype_values, "Unknown", proto),
  82                        proto,
  83                        length);
  84         }
  85
  86         length -= CHDLC_HDRLEN;
  87         p += CHDLC_HDRLEN;
  88
  89         switch (proto) {
  90         case ETHERTYPE_IP:
  91                 ip_print(gndo, p, length);
  92                 break;
  93 #ifdef INET6
  94         case ETHERTYPE_IPV6:
  95                 ip6_print(p, length);
  96                 break;
  97 #endif
  98         case CHDLC_TYPE_SLARP:
  99                 chdlc_slarp_print(p, length);
 100                 break;
 101 #if 0
 102         case CHDLC_TYPE_CDP:
 103                 chdlc_cdp_print(p, length);
 104                 break;
 105 #endif
 106         case ETHERTYPE_MPLS:
 107         case ETHERTYPE_MPLS_MULTI:
 108                 mpls_print(p, length);
 109                 break;
 110         case ETHERTYPE_ISO:
 111                 /* is the fudge byte set ? lets verify by spotting ISO headers */
 112                 if (*(p+1) == 0x81 ||
 113                     *(p+1) == 0x82 ||
 114                     *(p+1) == 0x83)
 115                     isoclns_print(p+1, length-1, length-1);
 116                 else
 117                     isoclns_print(p, length, length);
 118                 break;
 119         default:
 120                 if (!eflag)
 121                         printf("unknown CHDLC protocol (0x%04x)", proto);
 122                 break;
 123         }
 124
 125         return (CHDLC_HDRLEN);
 126 }
 127
 128 /*
 129  * The fixed-length portion of a SLARP packet.
 130  */
 131 struct cisco_slarp {
 132         u_int8_t code[4];
 133 #define SLARP_REQUEST   0
 134 #define SLARP_REPLY     1
 135 #define SLARP_KEEPALIVE 2
 136         union {
 137                 struct {
 138                         u_int8_t addr[4];
 139                         u_int8_t mask[4];
 140                 } addr;
 141                 struct {
 142                         u_int8_t myseq[4];
 143                         u_int8_t yourseq[4];
 144                         u_int8_t rel[2];
 145                 } keep;
 146         } un;
 147 };
 148
 149 #define SLARP_MIN_LEN   14
 150 #define SLARP_MAX_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         u_int sec,min,hrs,days;
 157
 158         printf("SLARP (length: %u), ",length);
 159         if (length < SLARP_MIN_LEN)
 160                 goto trunc;
 161
 162         slarp = (const struct cisco_slarp *)cp;
 163         TCHECK2(*slarp, SLARP_MIN_LEN);
 164         switch (EXTRACT_32BITS(&slarp->code)) {
 165         case SLARP_REQUEST:
 166                 printf("request");
 167                 /*
 168                  * At least according to William "Chops" Westfield's
 169                  * message in
 170                  *
 171                  *      http://www.nethelp.no/net/cisco-hdlc.txt
 172                  *
 173                  * the address and mask aren't used in requests -
 174                  * they're just zero.
 175                  */
 176                 break;
 177         case SLARP_REPLY:
 178                 printf("reply %s/%s",
 179                         ipaddr_string(&slarp->un.addr.addr),
 180                         ipaddr_string(&slarp->un.addr.mask));
 181                 break;
 182         case SLARP_KEEPALIVE:
 183                 printf("keepalive: mineseen=0x%08x, yourseen=0x%08x, reliability=0x%04x",
 184                        EXTRACT_32BITS(&slarp->un.keep.myseq),
 185                        EXTRACT_32BITS(&slarp->un.keep.yourseq),
 186                        EXTRACT_16BITS(&slarp->un.keep.rel));
 187
 188                 if (length >= SLARP_MAX_LEN) { /* uptime-stamp is optional */
 189                         cp += SLARP_MIN_LEN;
 190                         if (!TTEST2(*cp, 4))
 191                                 goto trunc;
 192                         sec = EXTRACT_32BITS(cp) / 1000;
 193                         min = sec / 60; sec -= min * 60;
 194                         hrs = min / 60; min -= hrs * 60;
 195                         days = hrs / 24; hrs -= days * 24;
 196                         printf(", link uptime=%ud%uh%um%us",days,hrs,min,sec);
 197                 }
 198                 break;
 199         default:
 200                 printf("0x%02x unknown", EXTRACT_32BITS(&slarp->code));
 201                 if (vflag <= 1)
 202                     print_unknown_data(cp+4,"\n\t",length-4);
 203                 break;
 204         }
 205
 206         if (SLARP_MAX_LEN < length && vflag)
 207                 printf(", (trailing junk: %d bytes)", length - SLARP_MAX_LEN);
 208         if (vflag > 1)
 209             print_unknown_data(cp+4,"\n\t",length-4);
 210         return;
 211
 212 trunc:
 213         printf("[|slarp]");
 214 }
 215
 216
 217 /*
 218  * Local Variables:
 219  * c-style: whitesmith
 220  * c-basic-offset: 8
 221  * End:
 222  */