The Tcpdump Group git mirrors - tcpdump/blob - netdissect.c

   1 /*
   2  * Copyright (c) 1988-1997
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Copyright (c) 1998-2012  Michael Richardson <mcr@tcpdump.org>
   6  *      The TCPDUMP project
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that: (1) source code distributions
  10  * retain the above copyright notice and this paragraph in its entirety, (2)
  11  * distributions including binary code include the above copyright notice and
  12  * this paragraph in its entirety in the documentation or other materials
  13  * provided with the distribution, and (3) all advertising materials mentioning
  14  * features or use of this software display the following acknowledgement:
  15  * ``This product includes software developed by the University of California,
  16  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  17  * the University nor the names of its contributors may be used to endorse
  18  * or promote products derived from this software without specific prior
  19  * written permission.
  20  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  21  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  22  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  23  */
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include <netdissect-stdinc.h>
  30 #include "netdissect.h"
  31 #include <string.h>
  32 #include <stdio.h>
  33
  34 #ifdef USE_LIBSMI
  35 #include <smi.h>
  36 #endif
  37
  38 /*
  39  * Initialize anything that must be initialized before dissecting
  40  * packets.
  41  *
  42  * This should be called at the beginning of the program; it does
  43  * not need to be called, and should not be called, for every
  44  * netdissect_options structure.
  45  */
  46 int
  47 nd_init(char *errbuf, size_t errbuf_size)
  48 {
  49 #ifdef _WIN32
  50         WORD wVersionRequested;
  51         WSADATA wsaData;
  52         int err;
  53
  54         /*
  55          * Request Winsock 2.2; we expect Winsock 2.
  56          */
  57         wVersionRequested = MAKEWORD(2, 2);
  58         err = WSAStartup(wVersionRequested, &wsaData);
  59         if (err != 0) {
  60                 strlcpy(errbuf, "Attempting to initialize Winsock failed",
  61                     errbuf_size);
  62                 return (-1);
  63         }
  64 #endif /* _WIN32 */
  65
  66 #ifdef USE_LIBSMI
  67         /*
  68          * XXX - should we just fail if this fails?  Some of the
  69          * libsmi calls may fail.
  70          */
  71         smiInit("tcpdump");
  72 #endif
  73
  74         /*
  75          * Clears the error buffer, and uses it so we don't get
  76          * "unused argument" warnings at compile time.
  77          */
  78         strlcpy(errbuf, "", errbuf_size);
  79         return (0);
  80 }
  81
  82 /*
  83  * Clean up anything that ndo_init() did.
  84  */
  85 void
  86 nd_cleanup(void)
  87 {
  88 #ifdef USE_LIBSMI
  89         /*
  90          * This appears, in libsmi 0.4.8, to do nothing if smiInit()
  91          * wasn't done or failed, so we call it unconditionally.
  92          */
  93         smiExit();
  94 #endif
  95
  96 #ifdef _WIN32
  97         /*
  98          * Undo the WSAStartup() call above.
  99          */
 100         WSACleanup();
 101 #endif
 102 }
 103
 104 int
 105 nd_have_smi_support(void)
 106 {
 107 #ifdef USE_LIBSMI
 108         return (1);
 109 #else
 110         return (0);
 111 #endif
 112 }
 113
 114 /*
 115  * Indicates whether an SMI module has been loaded, so that we can use
 116  * libsmi to translate OIDs.
 117  */
 118 int nd_smi_module_loaded;
 119
 120 int
 121 nd_load_smi_module(const char *module, char *errbuf, size_t errbuf_size)
 122 {
 123 #ifdef USE_LIBSMI
 124         if (smiLoadModule(module) == 0) {
 125                 snprintf(errbuf, errbuf_size, "could not load MIB module %s",
 126                     module);
 127                 return (-1);
 128         }
 129         nd_smi_module_loaded = 1;
 130         return (0);
 131 #else
 132         snprintf(errbuf, errbuf_size, "MIB module %s not loaded: no libsmi support",
 133             module);
 134         return (-1);
 135 #endif
 136 }
 137
 138 const char *
 139 nd_smi_version_string(void)
 140 {
 141 #ifdef USE_LIBSMI
 142         return (smi_version_string);
 143 #else
 144         return (NULL);
 145 #endif
 146 }