The Tcpdump Group git mirrors - libpcap/blob - fad-win32.c

   1 /*
   2  * Copyright (c) 2002 - 2005 NetGroup, Politecnico di Torino (Italy)
   3  * Copyright (c) 2005 - 2006 CACE Technologies, Davis (California)
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  * notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  * notice, this list of conditions and the following disclaimer in the
  14  * documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the Politecnico di Torino, CACE Technologies
  16  * nor the names of its contributors may be used to endorse or promote
  17  * products derived from this software without specific prior written
  18  * permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  24  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  26  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  30  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  *
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include "config.h"
  36 #endif
  37
  38 #define PCAP_DONT_INCLUDE_PCAP_BPF_H
  39 #include <pcap.h>
  40 #include <Packet32.h>
  41 #include <pcap-int.h>
  42
  43 #include <errno.h>
  44
  45 static int
  46 pcap_add_if_win32(pcap_if_t **devlist, char *name, const char *desc,
  47     char *errbuf)
  48 {
  49         pcap_if_t *curdev;
  50         npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES];
  51         LONG if_addr_size;
  52         int res = 0;
  53
  54         if_addr_size = MAX_NETWORK_ADDRESSES;
  55
  56         /*
  57          * Add an entry for this interface, with no addresses.
  58          */
  59         if (add_or_find_if(&curdev, devlist, name, 0, desc, errbuf) == -1) {
  60                 /*
  61                  * Failure.
  62                  */
  63                 return (-1);
  64         }
  65
  66         /*
  67          * Get the list of addresses for the interface.
  68          */
  69         if (!PacketGetNetInfoEx((void *)name, if_addrs, &if_addr_size)) {
  70                 /*
  71                  * Failure.
  72                  *
  73                  * We don't return an error, because this can happen with
  74                  * NdisWan interfaces, and we want to supply them even
  75                  * if we can't supply their addresses.
  76                  *
  77                  * We return an entry with an empty address list.
  78                  */
  79                 return (0);
  80         }
  81
  82         /*
  83          * Now add the addresses.
  84          */
  85         while (if_addr_size-- > 0) {
  86                 /*
  87                  * "curdev" is an entry for this interface; add an entry for
  88                  * this address to its list of addresses.
  89                  */
  90                 if(curdev == NULL)
  91                         break;
  92                 res = add_addr_to_dev(curdev,
  93                     (struct sockaddr *)&if_addrs[if_addr_size].IPAddress,
  94                     sizeof (struct sockaddr_storage),
  95                     (struct sockaddr *)&if_addrs[if_addr_size].SubnetMask,
  96                     sizeof (struct sockaddr_storage),
  97                     (struct sockaddr *)&if_addrs[if_addr_size].Broadcast,
  98                     sizeof (struct sockaddr_storage),
  99                     NULL,
 100                     0,
 101                     errbuf);
 102                 if (res == -1) {
 103                         /*
 104                          * Failure.
 105                          */
 106                         break;
 107                 }
 108         }
 109
 110         return (res);
 111 }
 112
 113
 114 /*
 115  * Get a list of all interfaces that are up and that we can open.
 116  * Returns -1 on error, 0 otherwise.
 117  * The list, as returned through "alldevsp", may be null if no interfaces
 118  * were up and could be opened.
 119  *
 120  * Win32 implementation, based on WinPcap
 121  */
 122 int
 123 pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf)
 124 {
 125         pcap_if_t *devlist = NULL;
 126         int ret = 0;
 127         const char *desc;
 128         char *AdaptersName;
 129         ULONG NameLength;
 130         char *name;
 131         char our_errbuf[PCAP_ERRBUF_SIZE+1];
 132
 133         /*
 134          * Find out how big a buffer we need.
 135          *
 136          * This call should always return FALSE; if the error is
 137          * ERROR_INSUFFICIENT_BUFFER, NameLength will be set to
 138          * the size of the buffer we need, otherwise there's a
 139          * problem, and NameLength should be set to 0.
 140          *
 141          * It shouldn't require NameLength to be set, but,
 142          * at least as of WinPcap 4.1.3, it checks whether
 143          * NameLength is big enough before it checks for a
 144          * NULL buffer argument, so, while it'll still do
 145          * the right thing if NameLength is uninitialized and
 146          * whatever junk happens to be there is big enough
 147          * (because the pointer argument will be null), it's
 148          * still reading an uninitialized variable.
 149          */
 150         NameLength = 0;
 151         if (!PacketGetAdapterNames(NULL, &NameLength))
 152         {
 153                 DWORD last_error = GetLastError();
 154
 155                 if (last_error != ERROR_INSUFFICIENT_BUFFER)
 156                 {
 157                         pcap_win32_err_to_str(last_error, our_errbuf);
 158                         snprintf(errbuf, PCAP_ERRBUF_SIZE,
 159                             "PacketGetAdapterNames: %s", our_errbuf);
 160                         return (-1);
 161                 }
 162         }
 163
 164         if (NameLength > 0)
 165                 AdaptersName = (char*) malloc(NameLength);
 166         else
 167         {
 168                 *alldevsp = NULL;
 169                 return 0;
 170         }
 171         if (AdaptersName == NULL)
 172         {
 173                 snprintf(errbuf, PCAP_ERRBUF_SIZE, "Cannot allocate enough memory to list the adapters.");
 174                 return (-1);
 175         }
 176
 177         if (!PacketGetAdapterNames(AdaptersName, &NameLength)) {
 178                 pcap_win32_err_to_str(GetLastError(), our_errbuf);
 179                 snprintf(errbuf, PCAP_ERRBUF_SIZE, "PacketGetAdapterNames: %s",
 180                     our_errbuf);
 181                 free(AdaptersName);
 182                 return (-1);
 183         }
 184
 185         /*
 186          * "PacketGetAdapterNames()" returned a list of
 187          * null-terminated ASCII interface name strings,
 188          * terminated by a null string, followed by a list
 189          * of null-terminated ASCII interface description
 190          * strings, terminated by a null string.
 191          * This means there are two ASCII nulls at the end
 192          * of the first list.
 193          *
 194          * Find the end of the first list; that's the
 195          * beginning of the second list.
 196          */
 197         desc = &AdaptersName[0];
 198         while (*desc != '\0' || *(desc + 1) != '\0')
 199                 desc++;
 200
 201         /*
 202          * Found it - "desc" points to the first of the two
 203          * nulls at the end of the list of names, so the
 204          * first byte of the list of descriptions is two bytes
 205          * after it.
 206          */
 207         desc += 2;
 208
 209         /*
 210          * Loop over the elements in the first list.
 211          */
 212         name = &AdaptersName[0];
 213         while (*name != '\0') {
 214                 /*
 215                  * Add an entry for this interface.
 216                  */
 217                 if (pcap_add_if_win32(&devlist, name, desc, errbuf) == -1) {
 218                         /*
 219                          * Failure.
 220                          */
 221                         ret = -1;
 222                         break;
 223                 }
 224                 name += strlen(name) + 1;
 225                 desc += strlen(desc) + 1;
 226         }
 227
 228         if (ret != -1) {
 229                 /*
 230                  * We haven't had any errors yet; do any platform-specific
 231                  * operations to add devices.
 232                  */
 233                 if (pcap_platform_finddevs(&devlist, errbuf) < 0)
 234                         ret = -1;
 235         }
 236
 237         if (ret == -1) {
 238                 /*
 239                  * We had an error; free the list we've been constructing.
 240                  */
 241                 if (devlist != NULL) {
 242                         pcap_freealldevs(devlist);
 243                         devlist = NULL;
 244                 }
 245         }
 246
 247         *alldevsp = devlist;
 248         free(AdaptersName);
 249         return (ret);
 250 }