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 1.43 1999-10-17 21:37:15 mcr Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_NET_SLIP_H
  28 #include <sys/param.h>
  29 #include <sys/time.h>
  30 #include <sys/timeb.h>
  31 #include <sys/file.h>
  32 #include <sys/ioctl.h>
  33 #include <sys/mbuf.h>
  34 #include <sys/socket.h>
  35
  36 #if __STDC__
  37 struct rtentry;
  38 #endif
  39 #include <net/if.h>
  40
  41 #include <netinet/in.h>
  42 #include <netinet/in_systm.h>
  43 #include <netinet/ip.h>
  44 #include <netinet/if_ether.h>
  45 #include <netinet/udp.h>
  46 #include <netinet/tcp.h>
  47
  48 #include <net/slcompress.h>
  49 #include <net/slip.h>
  50
  51 #include <ctype.h>
  52 #include <netdb.h>
  53 #include <pcap.h>
  54 #include <stdio.h>
  55
  56 #include "interface.h"
  57 #include "addrtoname.h"
  58 #include "extract.h"                    /* must come after interface.h */
  59
  60 static u_int lastlen[2][256];
  61 static u_int lastconn = 255;
  62
  63 static void sliplink_print(const u_char *, const struct ip *, u_int);
  64 static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
  65
  66 /* XXX BSD/OS 2.1 compatibility */
  67 #if !defined(SLIP_HDRLEN) && defined(SLC_BPFHDR)
  68 #define SLIP_HDRLEN SLC_BPFHDR
  69 #define SLX_DIR 0
  70 #define SLX_CHDR (SLC_BPFHDRLEN - 1)
  71 #define CHDR_LEN (SLC_BPFHDR - SLC_BPFHDRLEN)
  72 #endif
  73
  74 /* XXX needs more hacking to work right */
  75
  76 void
  77 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
  78 {
  79         register u_int caplen = h->caplen;
  80         register u_int length = h->len;
  81         register const struct ip *ip;
  82
  83         ts_print(&h->ts);
  84
  85         if (caplen < SLIP_HDRLEN) {
  86                 printf("[|slip]");
  87                 goto out;
  88         }
  89         /*
  90          * Some printers want to get back at the link level addresses,
  91          * and/or check that they're not walking off the end of the packet.
  92          * Rather than pass them all the way down, we set these globals.
  93          */
  94         packetp = p;
  95         snapend = p + caplen;
  96
  97         length -= SLIP_HDRLEN;
  98
  99         ip = (struct ip *)(p + SLIP_HDRLEN);
 100
 101         if (eflag)
 102                 sliplink_print(p, ip, length);
 103
 104         ip_print((u_char *)ip, length);
 105
 106         if (xflag)
 107                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
 108  out:
 109         putchar('\n');
 110 }
 111
 112
 113 void
 114 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 115 {
 116         register u_int caplen = h->caplen;
 117         register u_int length = h->len;
 118         register const struct ip *ip;
 119
 120         ts_print(&h->ts);
 121
 122         if (caplen < SLIP_HDRLEN) {
 123                 printf("[|slip]");
 124                 goto out;
 125         }
 126         /*
 127          * Some printers want to get back at the link level addresses,
 128          * and/or check that they're not walking off the end of the packet.
 129          * Rather than pass them all the way down, we set these globals.
 130          */
 131         packetp = p;
 132         snapend = p + caplen;
 133
 134         length -= SLIP_HDRLEN;
 135
 136         ip = (struct ip *)(p + SLIP_HDRLEN);
 137
 138 #ifdef notdef
 139         if (eflag)
 140                 sliplink_print(p, ip, length);
 141 #endif
 142
 143         ip_print((u_char *)ip, length);
 144
 145         if (xflag)
 146                 default_print((u_char *)ip, caplen - SLIP_HDRLEN);
 147  out:
 148         putchar('\n');
 149 }
 150
 151 static void
 152 sliplink_print(register const u_char *p, register const struct ip *ip,
 153                register u_int length)
 154 {
 155         int dir;
 156         u_int hlen;
 157
 158         dir = p[SLX_DIR];
 159         putchar(dir == SLIPDIR_IN ? 'I' : 'O');
 160         putchar(' ');
 161
 162         if (nflag) {
 163                 /* XXX just dump the header */
 164                 register int i;
 165
 166                 for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
 167                         printf("%02x.", p[i]);
 168                 printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
 169                 return;
 170         }
 171         switch (p[SLX_CHDR] & 0xf0) {
 172
 173         case TYPE_IP:
 174                 printf("ip %d: ", length + SLIP_HDRLEN);
 175                 break;
 176
 177         case TYPE_UNCOMPRESSED_TCP:
 178                 /*
 179                  * The connection id is stored in the IP protocol field.
 180                  * Get it from the link layer since sl_uncompress_tcp()
 181                  * has restored the IP header copy to IPPROTO_TCP.
 182                  */
 183                 lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
 184                 hlen = ip->ip_hl;
 185                 hlen += ((struct tcphdr *)&((int *)ip)[hlen])->th_off;
 186                 lastlen[dir][lastconn] = length - (hlen << 2);
 187                 printf("utcp %d: ", lastconn);
 188                 break;
 189
 190         default:
 191                 if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
 192                         compressed_sl_print(&p[SLX_CHDR], ip,
 193                             length, dir);
 194                         printf(": ");
 195                 } else
 196                         printf("slip-%d!: ", p[SLX_CHDR]);
 197         }
 198 }
 199
 200 static const u_char *
 201 print_sl_change(const char *str, register const u_char *cp)
 202 {
 203         register u_int i;
 204
 205         if ((i = *cp++) == 0) {
 206                 i = EXTRACT_16BITS(cp);
 207                 cp += 2;
 208         }
 209         printf(" %s%d", str, i);
 210         return (cp);
 211 }
 212
 213 static const u_char *
 214 print_sl_winchange(register const u_char *cp)
 215 {
 216         register short i;
 217
 218         if ((i = *cp++) == 0) {
 219                 i = EXTRACT_16BITS(cp);
 220                 cp += 2;
 221         }
 222         if (i >= 0)
 223                 printf(" W+%d", i);
 224         else
 225                 printf(" W%d", i);
 226         return (cp);
 227 }
 228
 229 static void
 230 compressed_sl_print(const u_char *chdr, const struct ip *ip,
 231                     u_int length, int dir)
 232 {
 233         register const u_char *cp = chdr;
 234         register u_int flags, hlen;
 235
 236         flags = *cp++;
 237         if (flags & NEW_C) {
 238                 lastconn = *cp++;
 239                 printf("ctcp %d", lastconn);
 240         } else
 241                 printf("ctcp *");
 242
 243         /* skip tcp checksum */
 244         cp += 2;
 245
 246         switch (flags & SPECIALS_MASK) {
 247         case SPECIAL_I:
 248                 printf(" *SA+%d", lastlen[dir][lastconn]);
 249                 break;
 250
 251         case SPECIAL_D:
 252                 printf(" *S+%d", lastlen[dir][lastconn]);
 253                 break;
 254
 255         default:
 256                 if (flags & NEW_U)
 257                         cp = print_sl_change("U=", cp);
 258                 if (flags & NEW_W)
 259                         cp = print_sl_winchange(cp);
 260                 if (flags & NEW_A)
 261                         cp = print_sl_change("A+", cp);
 262                 if (flags & NEW_S)
 263                         cp = print_sl_change("S+", cp);
 264                 break;
 265         }
 266         if (flags & NEW_I)
 267                 cp = print_sl_change("I+", cp);
 268
 269         /*
 270          * 'hlen' is the length of the uncompressed TCP/IP header (in words).
 271          * 'cp - chdr' is the length of the compressed header.
 272          * 'length - hlen' is the amount of data in the packet.
 273          */
 274         hlen = ip->ip_hl;
 275         hlen += ((struct tcphdr *)&((int32_t *)ip)[hlen])->th_off;
 276         lastlen[dir][lastconn] = length - (hlen << 2);
 277         printf(" %d (%d)", lastlen[dir][lastconn], cp - chdr);
 278 }
 279 #else
 280 #include <sys/types.h>
 281 #include <sys/time.h>
 282
 283 #include <pcap.h>
 284 #include <stdio.h>
 285
 286 #include "interface.h"
 287
 288 void
 289 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 290 {
 291
 292         error("not configured for slip");
 293         /* NOTREACHED */
 294 }
 295
 296 void
 297 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
 298 {
 299
 300         error("not configured for slip");
 301         /* NOTREACHED */
 302 }
 303 #endif