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 1.56 2000-10-10 05:06:10 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         ts_print(&h->ts);
  64
  65         if (caplen < SLIP_HDRLEN) {
  66                 printf("[|slip]");
  67                 goto out;
  68         }
  69         /*
  70          * Some printers want to get back at the link level addresses,
  71          * and/or check that they're not walking off the end of the packet.
  72          * Rather than pass them all the way down, we set these globals.
  73          */
  74         packetp = p;
  75         snapend = p + caplen;
  76
  77         length -= SLIP_HDRLEN;
  78
  79         ip = (struct ip *)(p + SLIP_HDRLEN);
  80
  81         if (eflag)
  82                 sliplink_print(p, ip, length);
  83
  84         switch (IP_V(ip)) {
  85         case 4:
  86                 ip_print((u_char *)ip, length);
  87                 break;
  88 #ifdef INET6
  89         case 6:
  90                 ip6_print((u_char *)ip, length);
  91                 break;
  92 #endif
  93         default:
  94                 printf ("ip v%d", IP_V(ip));
  95         }
  96
  97         if (xflag)
  98                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
  99  out:
 100         putchar('\n');
 101 }
 102
 103
 104 void
 105 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 106 {
 107         register u_int caplen = h->caplen;
 108         register u_int length = h->len;
 109         register const struct ip *ip;
 110
 111         ts_print(&h->ts);
 112
 113         if (caplen < SLIP_HDRLEN) {
 114                 printf("[|slip]");
 115                 goto out;
 116         }
 117         /*
 118          * Some printers want to get back at the link level addresses,
 119          * and/or check that they're not walking off the end of the packet.
 120          * Rather than pass them all the way down, we set these globals.
 121          */
 122         packetp = p;
 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 }
 141
 142 static void
 143 sliplink_print(register const u_char *p, register const struct ip *ip,
 144                register u_int length)
 145 {
 146         int dir;
 147         u_int hlen;
 148
 149         dir = p[SLX_DIR];
 150         putchar(dir == SLIPDIR_IN ? 'I' : 'O');
 151         putchar(' ');
 152
 153         if (nflag) {
 154                 /* XXX just dump the header */
 155                 register int i;
 156
 157                 for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
 158                         printf("%02x.", p[i]);
 159                 printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
 160                 return;
 161         }
 162         switch (p[SLX_CHDR] & 0xf0) {
 163
 164         case TYPE_IP:
 165                 printf("ip %d: ", length + SLIP_HDRLEN);
 166                 break;
 167
 168         case TYPE_UNCOMPRESSED_TCP:
 169                 /*
 170                  * The connection id is stored in the IP protocol field.
 171                  * Get it from the link layer since sl_uncompress_tcp()
 172                  * has restored the IP header copy to IPPROTO_TCP.
 173                  */
 174                 lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
 175                 hlen = IP_HL(ip);
 176                 hlen += TH_OFF((struct tcphdr *)&((int *)ip)[hlen]);
 177                 lastlen[dir][lastconn] = length - (hlen << 2);
 178                 printf("utcp %d: ", lastconn);
 179                 break;
 180
 181         default:
 182                 if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
 183                         compressed_sl_print(&p[SLX_CHDR], ip,
 184                             length, dir);
 185                         printf(": ");
 186                 } else
 187                         printf("slip-%d!: ", p[SLX_CHDR]);
 188         }
 189 }
 190
 191 static const u_char *
 192 print_sl_change(const char *str, register const u_char *cp)
 193 {
 194         register u_int i;
 195
 196         if ((i = *cp++) == 0) {
 197                 i = EXTRACT_16BITS(cp);
 198                 cp += 2;
 199         }
 200         printf(" %s%d", str, i);
 201         return (cp);
 202 }
 203
 204 static const u_char *
 205 print_sl_winchange(register const u_char *cp)
 206 {
 207         register short i;
 208
 209         if ((i = *cp++) == 0) {
 210                 i = EXTRACT_16BITS(cp);
 211                 cp += 2;
 212         }
 213         if (i >= 0)
 214                 printf(" W+%d", i);
 215         else
 216                 printf(" W%d", i);
 217         return (cp);
 218 }
 219
 220 static void
 221 compressed_sl_print(const u_char *chdr, const struct ip *ip,
 222                     u_int length, int dir)
 223 {
 224         register const u_char *cp = chdr;
 225         register u_int flags, hlen;
 226
 227         flags = *cp++;
 228         if (flags & NEW_C) {
 229                 lastconn = *cp++;
 230                 printf("ctcp %d", lastconn);
 231         } else
 232                 printf("ctcp *");
 233
 234         /* skip tcp checksum */
 235         cp += 2;
 236
 237         switch (flags & SPECIALS_MASK) {
 238         case SPECIAL_I:
 239                 printf(" *SA+%d", lastlen[dir][lastconn]);
 240                 break;
 241
 242         case SPECIAL_D:
 243                 printf(" *S+%d", lastlen[dir][lastconn]);
 244                 break;
 245
 246         default:
 247                 if (flags & NEW_U)
 248                         cp = print_sl_change("U=", cp);
 249                 if (flags & NEW_W)
 250                         cp = print_sl_winchange(cp);
 251                 if (flags & NEW_A)
 252                         cp = print_sl_change("A+", cp);
 253                 if (flags & NEW_S)
 254                         cp = print_sl_change("S+", cp);
 255                 break;
 256         }
 257         if (flags & NEW_I)
 258                 cp = print_sl_change("I+", cp);
 259
 260         /*
 261          * 'hlen' is the length of the uncompressed TCP/IP header (in words).
 262          * 'cp - chdr' is the length of the compressed header.
 263          * 'length - hlen' is the amount of data in the packet.
 264          */
 265         hlen = IP_HL(ip);
 266         hlen += TH_OFF((struct tcphdr *)&((int32_t *)ip)[hlen]);
 267         lastlen[dir][lastconn] = length - (hlen << 2);
 268         printf(" %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr));
 269 }