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 1.60 2002-12-18 08:53:24 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 "extract.h"                    /* must come after interface.h */
  39
  40 #include "ip.h"
  41 #include "tcp.h"
  42 #include "slip.h"
  43 #include "slcompress.h"
  44
  45 static u_int lastlen[2][256];
  46 static u_int lastconn = 255;
  47
  48 static void sliplink_print(const u_char *, const struct ip *, u_int);
  49 static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
  50
  51 void
  52 sl_if_print(u_char *user _U_, const struct pcap_pkthdr *h, const u_char *p)
  53 {
  54         register u_int caplen = h->caplen;
  55         register u_int length = h->len;
  56         register const struct ip *ip;
  57
  58         ++infodelay;
  59         ts_print(&h->ts);
  60
  61         if (caplen < SLIP_HDRLEN) {
  62                 printf("[|slip]");
  63                 goto out;
  64         }
  65
  66         /*
  67          * Some printers want to check that they're not walking off the
  68          * end of the packet.
  69          * Rather than pass it all the way down, we set this global.
  70          */
  71         snapend = p + caplen;
  72
  73         length -= SLIP_HDRLEN;
  74
  75         ip = (struct ip *)(p + SLIP_HDRLEN);
  76
  77         if (eflag)
  78                 sliplink_print(p, ip, length);
  79
  80         switch (IP_V(ip)) {
  81         case 4:
  82                 ip_print((u_char *)ip, length);
  83                 break;
  84 #ifdef INET6
  85         case 6:
  86                 ip6_print((u_char *)ip, length);
  87                 break;
  88 #endif
  89         default:
  90                 printf ("ip v%d", IP_V(ip));
  91         }
  92
  93         if (xflag)
  94                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
  95  out:
  96         putchar('\n');
  97         --infodelay;
  98         if (infoprint)
  99                 info(0);
 100 }
 101
 102
 103 void
 104 sl_bsdos_if_print(u_char *user _U_, const struct pcap_pkthdr *h, const u_char *p)
 105 {
 106         register u_int caplen = h->caplen;
 107         register u_int length = h->len;
 108         register const struct ip *ip;
 109
 110         ++infodelay;
 111         ts_print(&h->ts);
 112
 113         if (caplen < SLIP_HDRLEN) {
 114                 printf("[|slip]");
 115                 goto out;
 116         }
 117
 118         /*
 119          * Some printers want to check that they're not walking off the
 120          * end of the packet.
 121          * Rather than pass it all the way down, we set this global.
 122          */
 123         snapend = p + caplen;
 124
 125         length -= SLIP_HDRLEN;
 126
 127         ip = (struct ip *)(p + SLIP_HDRLEN);
 128
 129 #ifdef notdef
 130         if (eflag)
 131                 sliplink_print(p, ip, length);
 132 #endif
 133
 134         ip_print((u_char *)ip, length);
 135
 136         if (xflag)
 137                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
 138  out:
 139         putchar('\n');
 140         --infodelay;
 141         if (infoprint)
 142                 info(0);
 143 }
 144
 145 static void
 146 sliplink_print(register const u_char *p, register const struct ip *ip,
 147                register u_int length)
 148 {
 149         int dir;
 150         u_int hlen;
 151
 152         dir = p[SLX_DIR];
 153         putchar(dir == SLIPDIR_IN ? 'I' : 'O');
 154         putchar(' ');
 155
 156         if (nflag) {
 157                 /* XXX just dump the header */
 158                 register int i;
 159
 160                 for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
 161                         printf("%02x.", p[i]);
 162                 printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
 163                 return;
 164         }
 165         switch (p[SLX_CHDR] & 0xf0) {
 166
 167         case TYPE_IP:
 168                 printf("ip %d: ", length + SLIP_HDRLEN);
 169                 break;
 170
 171         case TYPE_UNCOMPRESSED_TCP:
 172                 /*
 173                  * The connection id is stored in the IP protocol field.
 174                  * Get it from the link layer since sl_uncompress_tcp()
 175                  * has restored the IP header copy to IPPROTO_TCP.
 176                  */
 177                 lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
 178                 hlen = IP_HL(ip);
 179                 hlen += TH_OFF((struct tcphdr *)&((int *)ip)[hlen]);
 180                 lastlen[dir][lastconn] = length - (hlen << 2);
 181                 printf("utcp %d: ", lastconn);
 182                 break;
 183
 184         default:
 185                 if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
 186                         compressed_sl_print(&p[SLX_CHDR], ip,
 187                             length, dir);
 188                         printf(": ");
 189                 } else
 190                         printf("slip-%d!: ", p[SLX_CHDR]);
 191         }
 192 }
 193
 194 static const u_char *
 195 print_sl_change(const char *str, register const u_char *cp)
 196 {
 197         register u_int i;
 198
 199         if ((i = *cp++) == 0) {
 200                 i = EXTRACT_16BITS(cp);
 201                 cp += 2;
 202         }
 203         printf(" %s%d", str, i);
 204         return (cp);
 205 }
 206
 207 static const u_char *
 208 print_sl_winchange(register const u_char *cp)
 209 {
 210         register short i;
 211
 212         if ((i = *cp++) == 0) {
 213                 i = EXTRACT_16BITS(cp);
 214                 cp += 2;
 215         }
 216         if (i >= 0)
 217                 printf(" W+%d", i);
 218         else
 219                 printf(" W%d", i);
 220         return (cp);
 221 }
 222
 223 static void
 224 compressed_sl_print(const u_char *chdr, const struct ip *ip,
 225                     u_int length, int dir)
 226 {
 227         register const u_char *cp = chdr;
 228         register u_int flags, hlen;
 229
 230         flags = *cp++;
 231         if (flags & NEW_C) {
 232                 lastconn = *cp++;
 233                 printf("ctcp %d", lastconn);
 234         } else
 235                 printf("ctcp *");
 236
 237         /* skip tcp checksum */
 238         cp += 2;
 239
 240         switch (flags & SPECIALS_MASK) {
 241         case SPECIAL_I:
 242                 printf(" *SA+%d", lastlen[dir][lastconn]);
 243                 break;
 244
 245         case SPECIAL_D:
 246                 printf(" *S+%d", lastlen[dir][lastconn]);
 247                 break;
 248
 249         default:
 250                 if (flags & NEW_U)
 251                         cp = print_sl_change("U=", cp);
 252                 if (flags & NEW_W)
 253                         cp = print_sl_winchange(cp);
 254                 if (flags & NEW_A)
 255                         cp = print_sl_change("A+", cp);
 256                 if (flags & NEW_S)
 257                         cp = print_sl_change("S+", cp);
 258                 break;
 259         }
 260         if (flags & NEW_I)
 261                 cp = print_sl_change("I+", cp);
 262
 263         /*
 264          * 'hlen' is the length of the uncompressed TCP/IP header (in words).
 265          * 'cp - chdr' is the length of the compressed header.
 266          * 'length - hlen' is the amount of data in the packet.
 267          */
 268         hlen = IP_HL(ip);
 269         hlen += TH_OFF((struct tcphdr *)&((int32_t *)ip)[hlen]);
 270         lastlen[dir][lastconn] = length - (hlen << 2);
 271         printf(" %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr));
 272 }