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

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994
   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 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include <string.h>
  27 #include <tcpdump-stdinc.h>
  28
  29 #include <stdio.h>
  30
  31 struct ipcomp {
  32         u_int8_t comp_nxt;      /* Next Header */
  33         u_int8_t comp_flags;    /* Length of data, in 32bit */
  34         u_int16_t comp_cpi;     /* Compression parameter index */
  35 };
  36
  37 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
  38 #include <zlib.h>
  39 #endif
  40
  41 #include "interface.h"
  42 #include "extract.h"
  43
  44 int
  45 ipcomp_print(register const u_char *bp, int *nhdr _U_)
  46 {
  47         register const struct ipcomp *ipcomp;
  48         register const u_char *ep;
  49         u_int16_t cpi;
  50 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
  51         int advance;
  52 #endif
  53
  54         ipcomp = (struct ipcomp *)bp;
  55         cpi = EXTRACT_16BITS(&ipcomp->comp_cpi);
  56
  57         /* 'ep' points to the end of available data. */
  58         ep = snapend;
  59
  60         if ((u_char *)(ipcomp + 1) >= ep - sizeof(struct ipcomp)) {
  61                 fputs("[|IPCOMP]", stdout);
  62                 goto fail;
  63         }
  64         printf("IPComp(cpi=0x%04x)", cpi);
  65
  66 #if defined(HAVE_LIBZ) && defined(HAVE_ZLIB_H)
  67         if (1)
  68                 goto fail;
  69
  70         /*
  71          * We may want to decompress the packet here.  Packet buffer
  72          * management is a headache (if we decompress, packet will become
  73          * larger).
  74          */
  75         if (nhdr)
  76                 *nhdr = ipcomp->comp_nxt;
  77         advance = sizeof(struct ipcomp);
  78
  79         printf(": ");
  80         return advance;
  81
  82 #endif
  83 fail:
  84         return -1;
  85 }