tinc-vpn.org Git - tinc/blob - src/mingw/device.c

   1 /*
   2     device.c -- Interaction with Windows tap driver in a MinGW environment
   3     Copyright (C) 2002-2005 Ivo Timmermans,
   4                   2002-2009 Guus Sliepen <guus@tinc-vpn.org>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id$
  21 */
  22
  23 #include "system.h"
  24
  25 #include <windows.h>
  26 #include <winioctl.h>
  27
  28 #include "conf.h"
  29 #include "logger.h"
  30 #include "net.h"
  31 #include "route.h"
  32 #include "utils.h"
  33 #include "xalloc.h"
  34
  35 #include "mingw/common.h"
  36
  37 int device_fd = -1;
  38 static HANDLE device_handle = INVALID_HANDLE_VALUE;
  39 char *device = NULL;
  40 char *iface = NULL;
  41 static char *device_info = NULL;
  42
  43 static int device_total_in = 0;
  44 static int device_total_out = 0;
  45
  46 extern char *myport;
  47
  48 static DWORD WINAPI tapreader(void *bla) {
  49         int status;
  50         long len;
  51         OVERLAPPED overlapped;
  52         vpn_packet_t packet;
  53
  54         logger(LOG_DEBUG, _("Tap reader running"));
  55
  56         /* Read from tap device and send to parent */
  57
  58         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
  59
  60         for(;;) {
  61                 overlapped.Offset = 0;
  62                 overlapped.OffsetHigh = 0;
  63                 ResetEvent(overlapped.hEvent);
  64
  65                 status = ReadFile(device_handle, packet.data, MTU, &len, &overlapped);
  66
  67                 if(!status) {
  68                         if(GetLastError() == ERROR_IO_PENDING) {
  69                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
  70                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
  71                                         continue;
  72                         } else {
  73                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
  74                                            device, strerror(errno));
  75                                 return -1;
  76                         }
  77                 }
  78
  79                 EnterCriticalSection(&mutex);
  80                 packet.len = len;
  81                 packet.priority = 0;
  82                 route(myself, &packet);
  83                 LeaveCriticalSection(&mutex);
  84         }
  85 }
  86
  87 bool setup_device(void)
  88 {
  89         HKEY key, key2;
  90         int i;
  91
  92         char regpath[1024];
  93         char adapterid[1024];
  94         char adaptername[1024];
  95         char tapname[1024];
  96         long len;
  97         unsigned long status;
  98
  99         bool found = false;
 100
 101         int sock, err;
 102         HANDLE thread;
 103
 104         struct addrinfo *ai;
 105         struct addrinfo hint = {
 106                 .ai_family = AF_UNSPEC,
 107                 .ai_socktype = SOCK_STREAM,
 108                 .ai_protocol = IPPROTO_TCP,
 109                 .ai_flags = 0,
 110         };
 111
 112         cp();
 113
 114         get_config_string(lookup_config(config_tree, "Device"), &device);
 115         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 116
 117         /* Open registry and look for network adapters */
 118
 119         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
 120                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 121                 return false;
 122         }
 123
 124         for (i = 0; ; i++) {
 125                 len = sizeof(adapterid);
 126                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 127                         break;
 128
 129                 /* Find out more about this adapter */
 130
 131                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
 132
 133                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 134                         continue;
 135
 136                 len = sizeof(adaptername);
 137                 err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 138
 139                 RegCloseKey(key2);
 140
 141                 if(err)
 142                         continue;
 143
 144                 if(device) {
 145                         if(!strcmp(device, adapterid)) {
 146                                 found = true;
 147                                 break;
 148                         } else
 149                                 continue;
 150                 }
 151
 152                 if(iface) {
 153                         if(!strcmp(iface, adaptername)) {
 154                                 found = true;
 155                                 break;
 156                         } else
 157                                 continue;
 158                 }
 159
 160                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 161                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 162                 if(device_handle != INVALID_HANDLE_VALUE) {
 163                         found = true;
 164                         break;
 165                 }
 166         }
 167
 168         RegCloseKey(key);
 169
 170         if(!found) {
 171                 logger(LOG_ERR, _("No Windows tap device found!"));
 172                 return false;
 173         }
 174
 175         if(!device)
 176                 device = xstrdup(adapterid);
 177
 178         if(!iface)
 179                 iface = xstrdup(adaptername);
 180
 181         /* Try to open the corresponding tap device */
 182
 183         if(device_handle == INVALID_HANDLE_VALUE) {
 184                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 185                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 186         }
 187
 188         if(device_handle == INVALID_HANDLE_VALUE) {
 189                 logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device: %s"), device, iface, winerror(GetLastError()));
 190                 return false;
 191         }
 192
 193         /* Get MAC address from tap device */
 194
 195         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 196                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
 197                 return false;
 198         }
 199
 200         if(routing_mode == RMODE_ROUTER) {
 201                 overwrite_mac = 1;
 202         }
 203
 204         /* Start the tap reader */
 205
 206         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 207
 208         if(!thread) {
 209                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 210                 return false;
 211         }
 212
 213         /* Set media status for newer TAP-Win32 devices */
 214
 215         status = true;
 216         DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof(status), &status, sizeof(status), &len, NULL);
 217
 218         device_info = _("Windows tap device");
 219
 220         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 221
 222         return true;
 223 }
 224
 225 void close_device(void)
 226 {
 227         cp();
 228
 229         CloseHandle(device_handle);
 230
 231         free(device);
 232         free(iface);
 233 }
 234
 235 bool read_packet(vpn_packet_t *packet)
 236 {
 237         return false;
 238 }
 239
 240 bool write_packet(vpn_packet_t *packet)
 241 {
 242         long lenout;
 243         OVERLAPPED overlapped = {0};
 244
 245         cp();
 246
 247         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 248                            packet->len, device_info);
 249
 250         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 251                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 252                 return false;
 253         }
 254
 255         device_total_out += packet->len;
 256
 257         return true;
 258 }
 259
 260 void dump_device_stats(void)
 261 {
 262         cp();
 263
 264         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 265         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 266         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 267 }