www.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) 2002-2003 Ivo Timmermans <ivo@o2w.nl>,
   4                   2002-2003 Guus Sliepen <guus@sliepen.eu.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: device.c,v 1.1.2.13 2003/08/08 19:49:47 guus Exp $
  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 #define REG_CONTROL_NET      "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
  36
  37 #define USERMODEDEVICEDIR "\\\\.\\"
  38 #define USERDEVICEDIR "\\??\\"
  39 #define TAPSUFFIX     ".tap"
  40
  41 #define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_PHYSICAL_NETCARD | 8000, request, method, FILE_ANY_ACCESS)
  42
  43 #define TAP_IOCTL_GET_LASTMAC    TAP_CONTROL_CODE(0, METHOD_BUFFERED)
  44 #define TAP_IOCTL_GET_MAC        TAP_CONTROL_CODE(1, METHOD_BUFFERED)
  45 #define TAP_IOCTL_SET_STATISTICS TAP_CONTROL_CODE(2, METHOD_BUFFERED)
  46
  47 int device_fd = 0;
  48 HANDLE device_handle = INVALID_HANDLE_VALUE;
  49 char *device = NULL;
  50 char *iface = NULL;
  51 char *device_info = NULL;
  52
  53 int device_total_in = 0;
  54 int device_total_out = 0;
  55
  56 extern char *myport;
  57
  58 DWORD WINAPI tapreader(void *bla) {
  59         int sock, err, status;
  60         struct addrinfo *ai;
  61         struct addrinfo hint = {
  62                 .ai_family = AF_UNSPEC,
  63                 .ai_socktype = SOCK_DGRAM,
  64                 .ai_protocol = IPPROTO_UDP,
  65                 .ai_flags = 0,
  66         };
  67         char buf[MTU];
  68         long len;
  69         OVERLAPPED overlapped;
  70
  71         /* Open a socket to the parent process */
  72
  73         err = getaddrinfo(NULL, myport, &hint, &ai);
  74
  75         if(err || !ai) {
  76                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
  77                 return -1;
  78         }
  79
  80         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
  81
  82         freeaddrinfo(ai);
  83
  84         if(sock < 0) {
  85                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  86                 return -1;
  87         }
  88
  89         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  90                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  91                 return -1;
  92         }
  93
  94         logger(LOG_DEBUG, _("Tap reader running"));
  95
  96         /* Read from tap device and send to parent */
  97
  98         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
  99
 100         for(;;) {
 101                 overlapped.Offset = 0;
 102                 overlapped.OffsetHigh = 0;
 103                 ResetEvent(overlapped.hEvent);
 104
 105                 status = ReadFile(device_handle, buf, sizeof(buf), &len, &overlapped);
 106
 107                 if(!status) {
 108                         if(GetLastError() == ERROR_IO_PENDING) {
 109                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 110                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 111                                         continue;
 112                         } else {
 113                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 114                                            device, strerror(errno));
 115                                 return -1;
 116                         }
 117                 }
 118
 119                 if(send(sock, buf, len, 0) <= 0)
 120                         return -1;
 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
 135         bool found = false;
 136
 137         int sock, err;
 138         HANDLE thread;
 139
 140         struct addrinfo *ai;
 141         struct addrinfo hint = {
 142                 .ai_family = AF_UNSPEC,
 143                 .ai_socktype = SOCK_DGRAM,
 144                 .ai_protocol = IPPROTO_UDP,
 145                 .ai_flags = 0,
 146         };
 147
 148         cp();
 149
 150         get_config_string(lookup_config(config_tree, "Device"), &device);
 151         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 152
 153         /* Open registry and look for network adapters */
 154
 155         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
 156                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 157                 return false;
 158         }
 159
 160         for (i = 0; ; i++) {
 161                 len = sizeof(adapterid);
 162                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 163                         break;
 164
 165                 /* Find out more about this adapter */
 166
 167                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
 168
 169                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 170                         continue;
 171
 172                 len = sizeof(adaptername);
 173                 err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 174
 175                 RegCloseKey(key2);
 176
 177                 if(err)
 178                         continue;
 179
 180                 if(device) {
 181                         if(!strcmp(device, adapterid)) {
 182                                 found = true;
 183                                 break;
 184                         } else
 185                                 continue;
 186                 }
 187
 188                 if(iface) {
 189                         if(!strcmp(iface, adaptername)) {
 190                                 found = true;
 191                                 break;
 192                         } else
 193                                 continue;
 194                 }
 195
 196                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 197                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 198                 if(device_handle != INVALID_HANDLE_VALUE) {
 199                         found = true;
 200                         break;
 201                 }
 202         }
 203
 204         RegCloseKey(key);
 205
 206         if(!found) {
 207                 logger(LOG_ERR, _("No Windows tap device found!"));
 208                 return false;
 209         }
 210
 211         if(!device)
 212                 device = xstrdup(adapterid);
 213
 214         if(!iface)
 215                 iface = xstrdup(adaptername);
 216
 217         /* Try to open the corresponding tap device */
 218
 219         if(device_handle == INVALID_HANDLE_VALUE) {
 220                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 221                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 222         }
 223
 224         if(device_handle == INVALID_HANDLE_VALUE) {
 225                 logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device: %s"), device, iface, winerror(GetLastError()));
 226                 return false;
 227         }
 228
 229         /* Get MAC address from tap device */
 230
 231         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 232                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
 233                 return false;
 234         }
 235
 236         if(routing_mode == RMODE_ROUTER) {
 237                 overwrite_mac = 1;
 238         }
 239
 240         /* Create a listening socket */
 241
 242         err = getaddrinfo(NULL, myport, &hint, &ai);
 243
 244         if(err || !ai) {
 245                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 246                 return false;
 247         }
 248
 249         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 250
 251         if(sock < 0) {
 252                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 253                 return false;
 254         }
 255
 256         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 257                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 258                 return false;
 259         }
 260
 261         freeaddrinfo(ai);
 262
 263         if(listen(sock, 1)) {
 264                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 265                 return false;
 266         }
 267
 268         /* Start the tap reader */
 269
 270         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 271
 272         if(!thread) {
 273                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 274                 return false;
 275         }
 276
 277         /* Wait for the tap reader to connect back to us */
 278
 279         if((device_fd = accept(sock, NULL, 0)) == -1) {
 280                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 281                 return false;
 282         }
 283
 284         closesocket(sock);
 285
 286         device_info = _("Windows tap device");
 287
 288         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 289
 290         return true;
 291 }
 292
 293 void close_device(void)
 294 {
 295         cp();
 296
 297         CloseHandle(device_handle);
 298 }
 299
 300 bool read_packet(vpn_packet_t *packet)
 301 {
 302         int lenin;
 303
 304         cp();
 305
 306         if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
 307                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 308                            device, strerror(errno));
 309                 return false;
 310         }
 311
 312         packet->len = lenin;
 313
 314         device_total_in += packet->len;
 315
 316         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 317                            device_info);
 318
 319         return true;
 320 }
 321
 322 bool write_packet(vpn_packet_t *packet)
 323 {
 324         long lenout;
 325         OVERLAPPED overlapped = {0};
 326
 327         cp();
 328
 329         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 330                            packet->len, device_info);
 331
 332         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 333                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 334                 return false;
 335         }
 336
 337         device_total_out += packet->len;
 338
 339         return true;
 340 }
 341
 342 void dump_device_stats(void)
 343 {
 344         cp();
 345
 346         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 347         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 348         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 349 }