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                   2002-2007 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 = 0;
  38 static HANDLE device_handle = INVALID_HANDLE_VALUE;
  39 char *device = NULL;
  40 char *iface = NULL;
  41 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 struct packetbuf {
  49         uint8_t data[MTU];
  50         length_t len;
  51 } *bufs;
  52
  53 static int nbufs = 64;
  54
  55 DWORD WINAPI tapreader(void *bla) {
  56         int sock, err, status;
  57         struct addrinfo *ai;
  58         struct addrinfo hint = {
  59                 .ai_family = AF_UNSPEC,
  60                 .ai_socktype = SOCK_STREAM,
  61                 .ai_protocol = IPPROTO_TCP,
  62                 .ai_flags = 0,
  63         };
  64         unsigned char bufno = 0;
  65         long len;
  66         OVERLAPPED overlapped;
  67
  68         /* Open a socket to the parent process */
  69
  70         err = getaddrinfo(NULL, myport, &hint, &ai);
  71
  72         if(err || !ai) {
  73                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
  74                 return -1;
  75         }
  76
  77         sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
  78
  79         if(sock < 0) {
  80                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  81                 freeaddrinfo(ai);
  82                 return -1;
  83         }
  84
  85         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  86                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  87                 freeaddrinfo(ai);
  88                 return -1;
  89         }
  90
  91         freeaddrinfo(ai);
  92
  93         logger(LOG_DEBUG, _("Tap reader running"));
  94
  95         /* Read from tap device and send to parent */
  96
  97         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
  98
  99         for(;;) {
 100                 overlapped.Offset = 0;
 101                 overlapped.OffsetHigh = 0;
 102                 ResetEvent(overlapped.hEvent);
 103
 104                 status = ReadFile(device_handle, bufs[bufno].data, MTU, &len, &overlapped);
 105
 106                 if(!status) {
 107                         if(GetLastError() == ERROR_IO_PENDING) {
 108                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 109                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 110                                         continue;
 111                         } else {
 112                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 113                                            device, strerror(errno));
 114                                 return -1;
 115                         }
 116                 }
 117
 118                 bufs[bufno].len = len;
 119                 if(send(sock, &bufno, 1, 0) <= 0)
 120                         return -1;
 121                 if(++bufno >= nbufs)
 122                         bufno = 0;
 123         }
 124 }
 125
 126 bool setup_device(void)
 127 {
 128         HKEY key, key2;
 129         int i;
 130
 131         char regpath[1024];
 132         char adapterid[1024];
 133         char adaptername[1024];
 134         char tapname[1024];
 135         long len;
 136         unsigned long status;
 137
 138         bool found = false;
 139
 140         int sock, err;
 141         HANDLE thread;
 142
 143         struct addrinfo *ai;
 144         struct addrinfo hint = {
 145                 .ai_family = AF_UNSPEC,
 146                 .ai_socktype = SOCK_STREAM,
 147                 .ai_protocol = IPPROTO_TCP,
 148                 .ai_flags = 0,
 149         };
 150
 151         cp();
 152
 153         get_config_string(lookup_config(config_tree, "Device"), &device);
 154         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 155
 156         /* Open registry and look for network adapters */
 157
 158         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
 159                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 160                 return false;
 161         }
 162
 163         for (i = 0; ; i++) {
 164                 len = sizeof(adapterid);
 165                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 166                         break;
 167
 168                 /* Find out more about this adapter */
 169
 170                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
 171
 172                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 173                         continue;
 174
 175                 len = sizeof(adaptername);
 176                 err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 177
 178                 RegCloseKey(key2);
 179
 180                 if(err)
 181                         continue;
 182
 183                 if(device) {
 184                         if(!strcmp(device, adapterid)) {
 185                                 found = true;
 186                                 break;
 187                         } else
 188                                 continue;
 189                 }
 190
 191                 if(iface) {
 192                         if(!strcmp(iface, adaptername)) {
 193                                 found = true;
 194                                 break;
 195                         } else
 196                                 continue;
 197                 }
 198
 199                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 200                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 201                 if(device_handle != INVALID_HANDLE_VALUE) {
 202                         found = true;
 203                         break;
 204                 }
 205         }
 206
 207         RegCloseKey(key);
 208
 209         if(!found) {
 210                 logger(LOG_ERR, _("No Windows tap device found!"));
 211                 return false;
 212         }
 213
 214         if(!device)
 215                 device = xstrdup(adapterid);
 216
 217         if(!iface)
 218                 iface = xstrdup(adaptername);
 219
 220         /* Try to open the corresponding tap device */
 221
 222         if(device_handle == INVALID_HANDLE_VALUE) {
 223                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 224                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 225         }
 226
 227         if(device_handle == INVALID_HANDLE_VALUE) {
 228                 logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device: %s"), device, iface, winerror(GetLastError()));
 229                 return false;
 230         }
 231
 232         /* Get MAC address from tap device */
 233
 234         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 235                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
 236                 return false;
 237         }
 238
 239         if(routing_mode == RMODE_ROUTER) {
 240                 overwrite_mac = 1;
 241         }
 242
 243         /* Set up ringbuffer */
 244
 245         get_config_int(lookup_config(config_tree, "RingBufferSize"), &nbufs);
 246         if(nbufs <= 1)
 247                 nbufs = 1;
 248         else if(nbufs > 256)
 249                 nbufs = 256;
 250
 251         bufs = xmalloc_and_zero(nbufs * sizeof *bufs);
 252
 253         /* Create a listening socket */
 254
 255         err = getaddrinfo(NULL, myport, &hint, &ai);
 256
 257         if(err || !ai) {
 258                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 259                 return false;
 260         }
 261
 262         sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 263
 264         if(sock < 0) {
 265                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 266                 return false;
 267         }
 268
 269         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 270                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 271                 return false;
 272         }
 273
 274         freeaddrinfo(ai);
 275
 276         if(listen(sock, 1)) {
 277                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 278                 return false;
 279         }
 280
 281         /* Start the tap reader */
 282
 283         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 284
 285         if(!thread) {
 286                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 287                 return false;
 288         }
 289
 290         /* Wait for the tap reader to connect back to us */
 291
 292         if((device_fd = accept(sock, NULL, 0)) == -1) {
 293                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 294                 return false;
 295         }
 296
 297         closesocket(sock);
 298
 299         /* Set media status for newer TAP-Win32 devices */
 300
 301         status = true;
 302         DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof(status), &status, sizeof(status), &len, NULL);
 303
 304         device_info = _("Windows tap device");
 305
 306         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 307
 308         return true;
 309 }
 310
 311 void close_device(void)
 312 {
 313         cp();
 314
 315         CloseHandle(device_handle);
 316 }
 317
 318 bool read_packet(vpn_packet_t *packet)
 319 {
 320         unsigned char bufno;
 321
 322         cp();
 323
 324         if((recv(device_fd, &bufno, 1, 0)) <= 0) {
 325                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 326                            device, strerror(errno));
 327                 return false;
 328         }
 329
 330         packet->len = bufs[bufno].len;
 331         memcpy(packet->data, bufs[bufno].data, bufs[bufno].len);
 332
 333         device_total_in += packet->len;
 334
 335         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 336                            device_info);
 337
 338         return true;
 339 }
 340
 341 bool write_packet(vpn_packet_t *packet)
 342 {
 343         long lenout;
 344         OVERLAPPED overlapped = {0};
 345
 346         cp();
 347
 348         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 349                            packet->len, device_info);
 350
 351         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 352                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 353                 return false;
 354         }
 355
 356         device_total_out += packet->len;
 357
 358         return true;
 359 }
 360
 361 void dump_device_stats(void)
 362 {
 363         cp();
 364
 365         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 366         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 367         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 368 }