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