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

   1 /*
   2  * Copyright (c) 1989, 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-sl.c,v 1.57 2001-07-05 18:54:17 guy Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <sys/param.h>
  32 #include <sys/time.h>
  33
  34 #include <netinet/in.h>
  35
  36 #include <ctype.h>
  37 #include <netdb.h>
  38 #include <pcap.h>
  39 #include <stdio.h>
  40
  41 #include "interface.h"
  42 #include "addrtoname.h"
  43 #include "extract.h"                    /* must come after interface.h */
  44
  45 #include "ip.h"
  46 #include "tcp.h"
  47 #include "slip.h"
  48 #include "slcompress.h"
  49
  50 static u_int lastlen[2][256];
  51 static u_int lastconn = 255;
  52
  53 static void sliplink_print(const u_char *, const struct ip *, u_int);
  54 static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
  55
  56 void
  57 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
  58 {
  59         register u_int caplen = h->caplen;
  60         register u_int length = h->len;
  61         register const struct ip *ip;
  62
  63         ++infodelay;
  64         ts_print(&h->ts);
  65
  66         if (caplen < SLIP_HDRLEN) {
  67                 printf("[|slip]");
  68                 goto out;
  69         }
  70         /*
  71          * Some printers want to get back at the link level addresses,
  72          * and/or check that they're not walking off the end of the packet.
  73          * Rather than pass them all the way down, we set these globals.
  74          */
  75         packetp = p;
  76         snapend = p + caplen;
  77
  78         length -= SLIP_HDRLEN;
  79
  80         ip = (struct ip *)(p + SLIP_HDRLEN);
  81
  82         if (eflag)
  83                 sliplink_print(p, ip, length);
  84
  85         switch (IP_V(ip)) {
  86         case 4:
  87                 ip_print((u_char *)ip, length);
  88                 break;
  89 #ifdef INET6
  90         case 6:
  91                 ip6_print((u_char *)ip, length);
  92                 break;
  93 #endif
  94         default:
  95                 printf ("ip v%d", IP_V(ip));
  96         }
  97
  98         if (xflag)
  99                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
 100  out:
 101         putchar('\n');
 102         --infodelay;
 103         if (infoprint)
 104                 info(0);
 105 }
 106
 107
 108 void
 109 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 110 {
 111         register u_int caplen = h->caplen;
 112         register u_int length = h->len;
 113         register const struct ip *ip;
 114
 115         ++infodelay;
 116         ts_print(&h->ts);
 117
 118         if (caplen < SLIP_HDRLEN) {
 119                 printf("[|slip]");
 120                 goto out;
 121         }
 122         /*
 123          * Some printers want to get back at the link level addresses,
 124          * and/or check that they're not walking off the end of the packet.
 125          * Rather than pass them all the way down, we set these globals.
 126          */
 127         packetp = p;
 128         snapend = p + caplen;
 129
 130         length -= SLIP_HDRLEN;
 131
 132         ip = (struct ip *)(p + SLIP_HDRLEN);
 133
 134 #ifdef notdef
 135         if (eflag)
 136                 sliplink_print(p, ip, length);
 137 #endif
 138
 139         ip_print((u_char *)ip, length);
 140
 141         if (xflag)
 142                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
 143  out:
 144         putchar('\n');
 145         --infodelay;
 146         if (infoprint)
 147                 info(0);
 148 }
 149
 150 static void
 151 sliplink_print(register const u_char *p, register const struct ip *ip,
 152                register u_int length)
 153 {
 154         int dir;
 155         u_int hlen;
 156
 157         dir = p[SLX_DIR];
 158         putchar(dir == SLIPDIR_IN ? 'I' : 'O');
 159         putchar(' ');
 160
 161         if (nflag) {
 162                 /* XXX just dump the header */
 163                 register int i;
 164
 165                 for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
 166                         printf("%02x.", p[i]);
 167                 printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
 168                 return;
 169         }
 170         switch (p[SLX_CHDR] & 0xf0) {
 171
 172         case TYPE_IP:
 173                 printf("ip %d: ", length + SLIP_HDRLEN);
 174                 break;
 175
 176         case TYPE_UNCOMPRESSED_TCP:
 177                 /*
 178                  * The connection id is stored in the IP protocol field.
 179                  * Get it from the link layer since sl_uncompress_tcp()
 180                  * has restored the IP header copy to IPPROTO_TCP.
 181                  */
 182                 lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
 183                 hlen = IP_HL(ip);
 184                 hlen += TH_OFF((struct tcphdr *)&((int *)ip)[hlen]);
 185                 lastlen[dir][lastconn] = length - (hlen << 2);
 186                 printf("utcp %d: ", lastconn);
 187                 break;
 188
 189         default:
 190                 if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
 191                         compressed_sl_print(&p[SLX_CHDR], ip,
 192                             length, dir);
 193                         printf(": ");
 194                 } else
 195                         printf("slip-%d!: ", p[SLX_CHDR]);
 196         }
 197 }
 198
 199 static const u_char *
 200 print_sl_change(const char *str, register const u_char *cp)
 201 {
 202         register u_int i;
 203
 204         if ((i = *cp++) == 0) {
 205                 i = EXTRACT_16BITS(cp);
 206                 cp += 2;
 207         }
 208         printf(" %s%d", str, i);
 209         return (cp);
 210 }
 211
 212 static const u_char *
 213 print_sl_winchange(register const u_char *cp)
 214 {
 215         register short i;
 216
 217         if ((i = *cp++) == 0) {
 218                 i = EXTRACT_16BITS(cp);
 219                 cp += 2;
 220         }
 221         if (i >= 0)
 222                 printf(" W+%d", i);
 223         else
 224                 printf(" W%d", i);
 225         return (cp);
 226 }
 227
 228 static void
 229 compressed_sl_print(const u_char *chdr, const struct ip *ip,
 230                     u_int length, int dir)
 231 {
 232         register const u_char *cp = chdr;
 233         register u_int flags, hlen;
 234
 235         flags = *cp++;
 236         if (flags & NEW_C) {
 237                 lastconn = *cp++;
 238                 printf("ctcp %d", lastconn);
 239         } else
 240                 printf("ctcp *");
 241
 242         /* skip tcp checksum */
 243         cp += 2;
 244
 245         switch (flags & SPECIALS_MASK) {
 246         case SPECIAL_I:
 247                 printf(" *SA+%d", lastlen[dir][lastconn]);
 248                 break;
 249
 250         case SPECIAL_D:
 251                 printf(" *S+%d", lastlen[dir][lastconn]);
 252                 break;
 253
 254         default:
 255                 if (flags & NEW_U)
 256                         cp = print_sl_change("U=", cp);
 257                 if (flags & NEW_W)
 258                         cp = print_sl_winchange(cp);
 259                 if (flags & NEW_A)
 260                         cp = print_sl_change("A+", cp);
 261                 if (flags & NEW_S)
 262                         cp = print_sl_change("S+", cp);
 263                 break;
 264         }
 265         if (flags & NEW_I)
 266                 cp = print_sl_change("I+", cp);
 267
 268         /*
 269          * 'hlen' is the length of the uncompressed TCP/IP header (in words).
 270          * 'cp - chdr' is the length of the compressed header.
 271          * 'length - hlen' is the amount of data in the packet.
 272          */
 273         hlen = IP_HL(ip);
 274         hlen += TH_OFF((struct tcphdr *)&((int32_t *)ip)[hlen]);
 275         lastlen[dir][lastconn] = length - (hlen << 2);
 276         printf(" %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr));
 277 }