git.meshlink.io Git - meshlink/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                   2002-2006 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         freeaddrinfo(ai);
  80
  81         if(sock < 0) {
  82                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  83                 return -1;
  84         }
  85
  86         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  87                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  88                 return -1;
  89         }
  90
  91         logger(LOG_DEBUG, _("Tap reader running"));
  92
  93         /* Read from tap device and send to parent */
  94
  95         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
  96
  97         for(;;) {
  98                 overlapped.Offset = 0;
  99                 overlapped.OffsetHigh = 0;
 100                 ResetEvent(overlapped.hEvent);
 101
 102                 status = ReadFile(device_handle, bufs[bufno].data, MTU, &len, &overlapped);
 103
 104                 if(!status) {
 105                         if(GetLastError() == ERROR_IO_PENDING) {
 106                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 107                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 108                                         continue;
 109                         } else {
 110                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 111                                            device, strerror(errno));
 112                                 return -1;
 113                         }
 114                 }
 115
 116                 bufs[bufno].len = len;
 117                 if(send(sock, &bufno, 1, 0) <= 0)
 118                         return -1;
 119                 if(++bufno >= nbufs)
 120                         bufno = 0;
 121         }
 122 }
 123
 124 bool setup_device(void)
 125 {
 126         HKEY key, key2;
 127         int i;
 128
 129         char regpath[1024];
 130         char adapterid[1024];
 131         char adaptername[1024];
 132         char tapname[1024];
 133         long len;
 134         unsigned long status;
 135
 136         bool found = false;
 137
 138         int sock, err;
 139         HANDLE thread;
 140
 141         struct addrinfo *ai;
 142         struct addrinfo hint = {
 143                 .ai_family = AF_UNSPEC,
 144                 .ai_socktype = SOCK_STREAM,
 145                 .ai_protocol = IPPROTO_TCP,
 146                 .ai_flags = 0,
 147         };
 148
 149         cp();
 150
 151         get_config_string(lookup_config(config_tree, "Device"), &device);
 152         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 153
 154         /* Open registry and look for network adapters */
 155
 156         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
 157                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 158                 return false;
 159         }
 160
 161         for (i = 0; ; i++) {
 162                 len = sizeof(adapterid);
 163                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 164                         break;
 165
 166                 /* Find out more about this adapter */
 167
 168                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
 169
 170                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 171                         continue;
 172
 173                 len = sizeof(adaptername);
 174                 err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 175
 176                 RegCloseKey(key2);
 177
 178                 if(err)
 179                         continue;
 180
 181                 if(device) {
 182                         if(!strcmp(device, adapterid)) {
 183                                 found = true;
 184                                 break;
 185                         } else
 186                                 continue;
 187                 }
 188
 189                 if(iface) {
 190                         if(!strcmp(iface, adaptername)) {
 191                                 found = true;
 192                                 break;
 193                         } else
 194                                 continue;
 195                 }
 196
 197                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 198                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 199                 if(device_handle != INVALID_HANDLE_VALUE) {
 200                         found = true;
 201                         break;
 202                 }
 203         }
 204
 205         RegCloseKey(key);
 206
 207         if(!found) {
 208                 logger(LOG_ERR, _("No Windows tap device found!"));
 209                 return false;
 210         }
 211
 212         if(!device)
 213                 device = xstrdup(adapterid);
 214
 215         if(!iface)
 216                 iface = xstrdup(adaptername);
 217
 218         /* Try to open the corresponding tap device */
 219
 220         if(device_handle == INVALID_HANDLE_VALUE) {
 221                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 222                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 223         }
 224
 225         if(device_handle == INVALID_HANDLE_VALUE) {
 226                 logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device: %s"), device, iface, winerror(GetLastError()));
 227                 return false;
 228         }
 229
 230         /* Get MAC address from tap device */
 231
 232         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 233                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
 234                 return false;
 235         }
 236
 237         if(routing_mode == RMODE_ROUTER) {
 238                 overwrite_mac = 1;
 239         }
 240
 241         /* Set up ringbuffer */
 242
 243         get_config_int(lookup_config(config_tree, "RingBufferSize"), &nbufs);
 244         if(nbufs <= 1)
 245                 nbufs = 1;
 246         else if(nbufs > 256)
 247                 nbufs = 256;
 248
 249         bufs = xmalloc_and_zero(nbufs * sizeof *bufs);
 250
 251         /* Create a listening socket */
 252
 253         err = getaddrinfo(NULL, myport, &hint, &ai);
 254
 255         if(err || !ai) {
 256                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 257                 return false;
 258         }
 259
 260         sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
 261
 262         if(sock < 0) {
 263                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 264                 return false;
 265         }
 266
 267         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 268                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 269                 return false;
 270         }
 271
 272         freeaddrinfo(ai);
 273
 274         if(listen(sock, 1)) {
 275                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 276                 return false;
 277         }
 278
 279         /* Start the tap reader */
 280
 281         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 282
 283         if(!thread) {
 284                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 285                 return false;
 286         }
 287
 288         /* Wait for the tap reader to connect back to us */
 289
 290         if((device_fd = accept(sock, NULL, 0)) == -1) {
 291                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 292                 return false;
 293         }
 294
 295         closesocket(sock);
 296
 297         /* Set media status for newer TAP-Win32 devices */
 298
 299         status = true;
 300         DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof(status), &status, sizeof(status), &len, NULL);
 301
 302         device_info = _("Windows tap device");
 303
 304         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 305
 306         return true;
 307 }
 308
 309 void close_device(void)
 310 {
 311         cp();
 312
 313         CloseHandle(device_handle);
 314 }
 315
 316 bool read_packet(vpn_packet_t *packet)
 317 {
 318         unsigned char bufno;
 319
 320         cp();
 321
 322         if((recv(device_fd, &bufno, 1, 0)) <= 0) {
 323                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 324                            device, strerror(errno));
 325                 return false;
 326         }
 327
 328         packet->len = bufs[bufno].len;
 329         memcpy(packet->data, bufs[bufno].data, bufs[bufno].len);
 330
 331         device_total_in += packet->len;
 332
 333         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 334                            device_info);
 335
 336         return true;
 337 }
 338
 339 bool write_packet(vpn_packet_t *packet)
 340 {
 341         long lenout;
 342         OVERLAPPED overlapped = {0};
 343
 344         cp();
 345
 346         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 347                            packet->len, device_info);
 348
 349         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 350                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 351                 return false;
 352         }
 353
 354         device_total_out += packet->len;
 355
 356         return true;
 357 }
 358
 359 void dump_device_stats(void)
 360 {
 361         cp();
 362
 363         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 364         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 365         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 366 }