contrib/libpcap/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 #include <pcap.h>
  39 #include <pcap-int.h>
  40 #include <Packet32.h>
  41
  42 #include <errno.h>
  43
  44 static int
  45 pcap_add_if_win32(pcap_if_t **devlist, char *name, const char *desc,
  46     char *errbuf)
  47 {
  48         pcap_if_t *curdev;
  49         npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES];
  50         LONG if_addr_size;
  51         int res = 0;
  52
  53         if_addr_size = MAX_NETWORK_ADDRESSES;
  54
  55         /*
  56          * Add an entry for this interface, with no addresses.
  57          */
  58         if (add_or_find_if(&curdev, devlist, name, 0, desc, errbuf) == -1) {
  59                 /*
  60                  * Failure.
  61                  */
  62                 return (-1);
  63         }
  64
  65         /*
  66          * Get the list of addresses for the interface.
  67          */
  68         if (!PacketGetNetInfoEx((void *)name, if_addrs, &if_addr_size)) {
  69                 /*
  70                  * Failure.
  71                  *
  72                  * We don't return an error, because this can happen with
  73                  * NdisWan interfaces, and we want to supply them even
  74                  * if we can't supply their addresses.
  75                  *
  76                  * We return an entry with an empty address list.
  77                  */
  78                 return (0);
  79         }
  80
  81         /*
  82          * Now add the addresses.
  83          */
  84         while (if_addr_size-- > 0) {
  85                 /*
  86                  * "curdev" is an entry for this interface; add an entry for
  87                  * this address to its list of addresses.
  88                  */
  89                 if(curdev == NULL)
  90                         break;
  91                 res = add_addr_to_dev(curdev,
  92                     (struct sockaddr *)&if_addrs[if_addr_size].IPAddress,
  93                     sizeof (struct sockaddr_storage),
  94                     (struct sockaddr *)&if_addrs[if_addr_size].SubnetMask,
  95                     sizeof (struct sockaddr_storage),
  96                     (struct sockaddr *)&if_addrs[if_addr_size].Broadcast,
  97                     sizeof (struct sockaddr_storage),
  98                     NULL,
  99                     0,
 100                     errbuf);
 101                 if (res == -1) {
 102                         /*
 103                          * Failure.
 104                          */
 105                         break;
 106                 }
 107         }
 108
 109         return (res);
 110 }
 111
 112
 113 /*
 114  * Get a list of all interfaces that are up and that we can open.
 115  * Returns -1 on error, 0 otherwise.
 116  * The list, as returned through "alldevsp", may be null if no interfaces
 117  * were up and could be opened.
 118  *
 119  * Win32 implementation, based on WinPcap
 120  */
 121 int
 122 pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf)
 123 {
 124         pcap_if_t *devlist = NULL;
 125         int ret = 0;
 126         const char *desc;
 127         char *AdaptersName;
 128         ULONG NameLength;
 129         char *name;
 130
 131         /*
 132          * Find out how big a buffer we need.
 133          *
 134          * This call should always return FALSE; if the error is
 135          * ERROR_INSUFFICIENT_BUFFER, NameLength will be set to
 136          * the size of the buffer we need, otherwise there's a
 137          * problem, and NameLength should be set to 0.
 138          *
 139          * It shouldn't require NameLength to be set, but,
 140          * at least as of WinPcap 4.1.3, it checks whether
 141          * NameLength is big enough before it checks for a
 142          * NULL buffer argument, so, while it'll still do
 143          * the right thing if NameLength is uninitialized and
 144          * whatever junk happens to be there is big enough
 145          * (because the pointer argument will be null), it's
 146          * still reading an uninitialized variable.
 147          */
 148         NameLength = 0;
 149         if (!PacketGetAdapterNames(NULL, &NameLength))
 150         {
 151                 DWORD last_error = GetLastError();
 152
 153                 if (last_error != ERROR_INSUFFICIENT_BUFFER)
 154                 {
 155                         snprintf(errbuf, PCAP_ERRBUF_SIZE,
 156                                 "PacketGetAdapterNames: %s",
 157                                 pcap_win32strerror());
 158                         return (-1);
 159                 }
 160         }
 161
 162         if (NameLength > 0)
 163                 AdaptersName = (char*) malloc(NameLength);
 164         else
 165         {
 166                 *alldevsp = NULL;
 167                 return 0;
 168         }
 169         if (AdaptersName == NULL)
 170         {
 171                 snprintf(errbuf, PCAP_ERRBUF_SIZE, "Cannot allocate enough memory to list the adapters.");
 172                 return (-1);
 173         }
 174
 175         if (!PacketGetAdapterNames(AdaptersName, &NameLength)) {
 176                 snprintf(errbuf, PCAP_ERRBUF_SIZE,
 177                         "PacketGetAdapterNames: %s",
 178                         pcap_win32strerror());
 179                 free(AdaptersName);
 180                 return (-1);
 181         }
 182
 183         /*
 184          * "PacketGetAdapterNames()" returned a list of
 185          * null-terminated ASCII interface name strings,
 186          * terminated by a null string, followed by a list
 187          * of null-terminated ASCII interface description
 188          * strings, terminated by a null string.
 189          * This means there are two ASCII nulls at the end
 190          * of the first list.
 191          *
 192          * Find the end of the first list; that's the
 193          * beginning of the second list.
 194          */
 195         desc = &AdaptersName[0];
 196         while (*desc != '\0' || *(desc + 1) != '\0')
 197                 desc++;
 198
 199         /*
 200          * Found it - "desc" points to the first of the two
 201          * nulls at the end of the list of names, so the
 202          * first byte of the list of descriptions is two bytes
 203          * after it.
 204          */
 205         desc += 2;
 206
 207         /*
 208          * Loop over the elements in the first list.
 209          */
 210         name = &AdaptersName[0];
 211         while (*name != '\0') {
 212                 /*
 213                  * Add an entry for this interface.
 214                  */
 215                 if (pcap_add_if_win32(&devlist, name, desc, errbuf) == -1) {
 216                         /*
 217                          * Failure.
 218                          */
 219                         ret = -1;
 220                         break;
 221                 }
 222                 name += strlen(name) + 1;
 223                 desc += strlen(desc) + 1;
 224         }
 225
 226         if (ret != -1) {
 227                 /*
 228                  * We haven't had any errors yet; do any platform-specific
 229                  * operations to add devices.
 230                  */
 231                 if (pcap_platform_finddevs(&devlist, errbuf) < 0)
 232                         ret = -1;
 233         }
 234
 235         if (ret == -1) {
 236                 /*
 237                  * We had an error; free the list we've been constructing.
 238                  */
 239                 if (devlist != NULL) {
 240                         pcap_freealldevs(devlist);
 241                         devlist = NULL;
 242                 }
 243         }
 244
 245         *alldevsp = devlist;
 246         free(AdaptersName);
 247         return (ret);
 248 }