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

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
   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 <tcpdump-stdinc.h>
  27
  28 #include "interface.h"
  29 #include "extract.h"
  30 #include "ethertype.h"
  31
  32 #include "ether.h"
  33
  34 struct symantec_header {
  35         uint8_t  stuff1[6];
  36         uint16_t ether_type;
  37         uint8_t  stuff2[36];
  38 };
  39
  40 static inline void
  41 symantec_hdr_print(netdissect_options *ndo, register const u_char *bp, u_int length)
  42 {
  43         register const struct symantec_header *sp;
  44         uint16_t etype;
  45
  46         sp = (const struct symantec_header *)bp;
  47
  48         etype = EXTRACT_16BITS(&sp->ether_type);
  49         if (!ndo->ndo_qflag) {
  50                 if (etype <= ETHERMTU)
  51                           ND_PRINT((ndo, "invalid ethertype %u", etype));
  52                 else
  53                           ND_PRINT((ndo, "ethertype %s (0x%04x)",
  54                                        tok2str(ethertype_values,"Unknown", etype),
  55                                        etype));
  56         } else {
  57                 if (etype <= ETHERMTU)
  58                           ND_PRINT((ndo, "invalid ethertype %u", etype));
  59                 else
  60                           ND_PRINT((ndo, "%s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", etype)));
  61         }
  62
  63         ND_PRINT((ndo, ", length %u: ", length));
  64 }
  65
  66 /*
  67  * This is the top level routine of the printer.  'p' points
  68  * to the ether header of the packet, 'h->ts' is the timestamp,
  69  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
  70  * is the number of bytes actually captured.
  71  */
  72 u_int
  73 symantec_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
  74 {
  75         u_int length = h->len;
  76         u_int caplen = h->caplen;
  77         struct symantec_header *sp;
  78         u_short ether_type;
  79
  80         if (caplen < sizeof (struct symantec_header)) {
  81                 ND_PRINT((ndo, "[|symantec]"));
  82                 return caplen;
  83         }
  84
  85         if (ndo->ndo_eflag)
  86                 symantec_hdr_print(ndo, p, length);
  87
  88         length -= sizeof (struct symantec_header);
  89         caplen -= sizeof (struct symantec_header);
  90         sp = (struct symantec_header *)p;
  91         p += sizeof (struct symantec_header);
  92
  93         ether_type = EXTRACT_16BITS(&sp->ether_type);
  94
  95         if (ether_type <= ETHERMTU) {
  96                 /* ether_type not known, print raw packet */
  97                 if (!ndo->ndo_eflag)
  98                         symantec_hdr_print(ndo, (u_char *)sp, length + sizeof (struct symantec_header));
  99
 100                 if (!ndo->ndo_suppress_default_print)
 101                         ND_DEFAULTPRINT(p, caplen);
 102         } else if (ethertype_print(ndo, ether_type, p, length, caplen) == 0) {
 103                 /* ether_type not known, print raw packet */
 104                 if (!ndo->ndo_eflag)
 105                         symantec_hdr_print(ndo, (u_char *)sp, length + sizeof (struct symantec_header));
 106
 107                 if (!ndo->ndo_suppress_default_print)
 108                         ND_DEFAULTPRINT(p, caplen);
 109         }
 110
 111         return (sizeof (struct symantec_header));
 112 }