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 #ifndef lint
  35 static const char rcsid[] _U_ =
  36     "@(#) $Header: /tcpdump/master/libpcap/fad-win32.c,v 1.15 2007-09-25 20:34:36 guy Exp $ (LBL)";
  37 #endif
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include "config.h"
  41 #endif
  42
  43 #include <pcap.h>
  44 #include <pcap-int.h>
  45 #include <Packet32.h>
  46
  47 #include <errno.h>
  48
  49 /*
  50  * Add an entry to the list of addresses for an interface.
  51  * "curdev" is the entry for that interface.
  52  */
  53 static int
  54 add_addr_to_list(pcap_if_t *curdev, struct sockaddr *addr,
  55     struct sockaddr *netmask, struct sockaddr *broadaddr,
  56     struct sockaddr *dstaddr, char *errbuf)
  57 {
  58         pcap_addr_t *curaddr, *prevaddr, *nextaddr;
  59
  60         /*
  61          * Allocate the new entry and fill it in.
  62          */
  63         curaddr = (pcap_addr_t*)malloc(sizeof(pcap_addr_t));
  64         if (curaddr == NULL) {
  65                 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
  66                     "malloc: %s", pcap_strerror(errno));
  67                 return (-1);
  68         }
  69
  70         curaddr->next = NULL;
  71         if (addr != NULL) {
  72                 curaddr->addr = (struct sockaddr*)dup_sockaddr(addr, sizeof(struct sockaddr_storage));
  73                 if (curaddr->addr == NULL) {
  74                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
  75                             "malloc: %s", pcap_strerror(errno));
  76                         free(curaddr);
  77                         return (-1);
  78                 }
  79         } else
  80                 curaddr->addr = NULL;
  81
  82         if (netmask != NULL) {
  83                 curaddr->netmask = (struct sockaddr*)dup_sockaddr(netmask, sizeof(struct sockaddr_storage));
  84                 if (curaddr->netmask == NULL) {
  85                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
  86                             "malloc: %s", pcap_strerror(errno));
  87                         free(curaddr);
  88                         return (-1);
  89                 }
  90         } else
  91                 curaddr->netmask = NULL;
  92
  93         if (broadaddr != NULL) {
  94                 curaddr->broadaddr = (struct sockaddr*)dup_sockaddr(broadaddr, sizeof(struct sockaddr_storage));
  95                 if (curaddr->broadaddr == NULL) {
  96                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
  97                             "malloc: %s", pcap_strerror(errno));
  98                         free(curaddr);
  99                         return (-1);
 100                 }
 101         } else
 102                 curaddr->broadaddr = NULL;
 103
 104         if (dstaddr != NULL) {
 105                 curaddr->dstaddr = (struct sockaddr*)dup_sockaddr(dstaddr, sizeof(struct sockaddr_storage));
 106                 if (curaddr->dstaddr == NULL) {
 107                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 108                             "malloc: %s", pcap_strerror(errno));
 109                         free(curaddr);
 110                         return (-1);
 111                 }
 112         } else
 113                 curaddr->dstaddr = NULL;
 114
 115         /*
 116          * Find the end of the list of addresses.
 117          */
 118         for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
 119                 nextaddr = prevaddr->next;
 120                 if (nextaddr == NULL) {
 121                         /*
 122                          * This is the end of the list.
 123                          */
 124                         break;
 125                 }
 126         }
 127
 128         if (prevaddr == NULL) {
 129                 /*
 130                  * The list was empty; this is the first member.
 131                  */
 132                 curdev->addresses = curaddr;
 133         } else {
 134                 /*
 135                  * "prevaddr" is the last member of the list; append
 136                  * this member to it.
 137                  */
 138                 prevaddr->next = curaddr;
 139         }
 140
 141         return (0);
 142 }
 143
 144
 145 static int
 146 pcap_add_if_win32(pcap_if_t **devlist, char *name, const char *desc,
 147     char *errbuf)
 148 {
 149         pcap_if_t *curdev;
 150         npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES];
 151         LONG if_addr_size;
 152         int res = 0;
 153
 154         if_addr_size = MAX_NETWORK_ADDRESSES;
 155
 156         /*
 157          * Add an entry for this interface, with no addresses.
 158          */
 159         if (add_or_find_if(&curdev, devlist, name, 0, desc, errbuf) == -1) {
 160                 /*
 161                  * Failure.
 162                  */
 163                 return (-1);
 164         }
 165
 166         /*
 167          * Get the list of addresses for the interface.
 168          */
 169         if (!PacketGetNetInfoEx((void *)name, if_addrs, &if_addr_size)) {
 170                 /*
 171                  * Failure.
 172                  *
 173                  * We don't return an error, because this can happen with
 174                  * NdisWan interfaces, and we want to supply them even
 175                  * if we can't supply their addresses.
 176                  *
 177                  * We return an entry with an empty address list.
 178                  */
 179                 return (0);
 180         }
 181
 182         /*
 183          * Now add the addresses.
 184          */
 185         while (if_addr_size-- > 0) {
 186                 /*
 187                  * "curdev" is an entry for this interface; add an entry for
 188                  * this address to its list of addresses.
 189                  */
 190                 if(curdev == NULL)
 191                         break;
 192                 res = add_addr_to_list(curdev,
 193                     (struct sockaddr *)&if_addrs[if_addr_size].IPAddress,
 194                     (struct sockaddr *)&if_addrs[if_addr_size].SubnetMask,
 195                     (struct sockaddr *)&if_addrs[if_addr_size].Broadcast,
 196                     NULL,
 197                         errbuf);
 198                 if (res == -1) {
 199                         /*
 200                          * Failure.
 201                          */
 202                         break;
 203                 }
 204         }
 205
 206         return (res);
 207 }
 208
 209
 210 /*
 211  * Get a list of all interfaces that are up and that we can open.
 212  * Returns -1 on error, 0 otherwise.
 213  * The list, as returned through "alldevsp", may be null if no interfaces
 214  * were up and could be opened.
 215  *
 216  * Win32 implementation, based on WinPcap
 217  */
 218 int
 219 pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf)
 220 {
 221         pcap_if_t *devlist = NULL;
 222         int ret = 0;
 223         const char *desc;
 224         char *AdaptersName;
 225         ULONG NameLength;
 226         char *name;
 227
 228         /*
 229          * Find out how big a buffer we need.
 230          *
 231          * This call should always return FALSE; if the error is
 232          * ERROR_INSUFFICIENT_BUFFER, NameLength will be set to
 233          * the size of the buffer we need, otherwise there's a
 234          * problem, and NameLength should be set to 0.
 235          *
 236          * It shouldn't require NameLength to be set, but,
 237          * at least as of WinPcap 4.1.3, it checks whether
 238          * NameLength is big enough before it checks for a
 239          * NULL buffer argument, so, while it'll still do
 240          * the right thing if NameLength is uninitialized and
 241          * whatever junk happens to be there is big enough
 242          * (because the pointer argument will be null), it's
 243          * still reading an uninitialized variable.
 244          */
 245         NameLength = 0;
 246         if (!PacketGetAdapterNames(NULL, &NameLength))
 247         {
 248                 DWORD last_error = GetLastError();
 249
 250                 if (last_error != ERROR_INSUFFICIENT_BUFFER)
 251                 {
 252                         snprintf(errbuf, PCAP_ERRBUF_SIZE,
 253                                 "PacketGetAdapterNames: %s",
 254                                 pcap_win32strerror());
 255                         return (-1);
 256                 }
 257         }
 258
 259         if (NameLength > 0)
 260                 AdaptersName = (char*) malloc(NameLength);
 261         else
 262         {
 263                 *alldevsp = NULL;
 264                 return 0;
 265         }
 266         if (AdaptersName == NULL)
 267         {
 268                 snprintf(errbuf, PCAP_ERRBUF_SIZE, "Cannot allocate enough memory to list the adapters.");
 269                 return (-1);
 270         }
 271
 272         if (!PacketGetAdapterNames(AdaptersName, &NameLength)) {
 273                 snprintf(errbuf, PCAP_ERRBUF_SIZE,
 274                         "PacketGetAdapterNames: %s",
 275                         pcap_win32strerror());
 276                 free(AdaptersName);
 277                 return (-1);
 278         }
 279
 280         /*
 281          * "PacketGetAdapterNames()" returned a list of
 282          * null-terminated ASCII interface name strings,
 283          * terminated by a null string, followed by a list
 284          * of null-terminated ASCII interface description
 285          * strings, terminated by a null string.
 286          * This means there are two ASCII nulls at the end
 287          * of the first list.
 288          *
 289          * Find the end of the first list; that's the
 290          * beginning of the second list.
 291          */
 292         desc = &AdaptersName[0];
 293         while (*desc != '\0' || *(desc + 1) != '\0')
 294                 desc++;
 295
 296         /*
 297          * Found it - "desc" points to the first of the two
 298          * nulls at the end of the list of names, so the
 299          * first byte of the list of descriptions is two bytes
 300          * after it.
 301          */
 302         desc += 2;
 303
 304         /*
 305          * Loop over the elements in the first list.
 306          */
 307         name = &AdaptersName[0];
 308         while (*name != '\0') {
 309                 /*
 310                  * Add an entry for this interface.
 311                  */
 312                 if (pcap_add_if_win32(&devlist, name, desc, errbuf) == -1) {
 313                         /*
 314                          * Failure.
 315                          */
 316                         ret = -1;
 317                         break;
 318                 }
 319                 name += strlen(name) + 1;
 320                 desc += strlen(desc) + 1;
 321         }
 322
 323         if (ret != -1) {
 324                 /*
 325                  * We haven't had any errors yet; do any platform-specific
 326                  * operations to add devices.
 327                  */
 328                 if (pcap_platform_finddevs(&devlist, errbuf) < 0)
 329                         ret = -1;
 330         }
 331
 332         if (ret == -1) {
 333                 /*
 334                  * We had an error; free the list we've been constructing.
 335                  */
 336                 if (devlist != NULL) {
 337                         pcap_freealldevs(devlist);
 338                         devlist = NULL;
 339                 }
 340         }
 341
 342         *alldevsp = devlist;
 343         free(AdaptersName);
 344         return (ret);
 345 }