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 1.1.2.10 2003/08/02 21:33:19 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 DWORD WINAPI tapreader(void *bla) {
  57         int sock, err, status;
  58         struct addrinfo *ai;
  59         struct addrinfo hint = {
  60                 .ai_family = AF_UNSPEC,
  61                 .ai_socktype = SOCK_DGRAM,
  62                 .ai_protocol = IPPROTO_UDP,
  63                 .ai_flags = 0,
  64         };
  65         char buf[MTU];
  66         long len;
  67         OVERLAPPED overlapped;
  68
  69         /* Open a socket to the parent process */
  70
  71         err = getaddrinfo(NULL, "12345", &hint, &ai);
  72
  73         if(err || !ai) {
  74                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
  75                 return -1;
  76         }
  77
  78         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
  79
  80         freeaddrinfo(ai);
  81
  82         if(sock < 0) {
  83                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  84                 return -1;
  85         }
  86
  87         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  88                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  89                 return -1;
  90         }
  91
  92         logger(LOG_DEBUG, _("Tap reader running"));
  93
  94         /* Read from tap device and send to parent */
  95
  96         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
  97
  98         for(;;) {
  99                 overlapped.Offset = 0;
 100                 overlapped.OffsetHigh = 0;
 101                 ResetEvent(overlapped.hEvent);
 102
 103                 status = ReadFile(device_handle, buf, sizeof(buf), &len, &overlapped);
 104
 105                 if(!status) {
 106                         if(GetLastError() == ERROR_IO_PENDING) {
 107                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 108                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 109                                         continue;
 110                         } else {
 111                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 112                                            device, strerror(errno));
 113                                 return -1;
 114                         }
 115                 }
 116
 117                 if(send(sock, buf, len, 0) <= 0)
 118                         return -1;
 119         }
 120 }
 121
 122 bool setup_device(void)
 123 {
 124         HKEY key, key2;
 125         int i;
 126
 127         char regpath[1024];
 128         char adapterid[1024];
 129         char adaptername[1024];
 130         char tapname[1024];
 131         long len;
 132
 133         bool found = false;
 134
 135         int sock, err;
 136         HANDLE thread;
 137
 138         struct addrinfo *ai;
 139         struct addrinfo hint = {
 140                 .ai_family = AF_UNSPEC,
 141                 .ai_socktype = SOCK_DGRAM,
 142                 .ai_protocol = IPPROTO_UDP,
 143                 .ai_flags = AI_PASSIVE,
 144         };
 145
 146         cp();
 147
 148         get_config_string(lookup_config(config_tree, "Device"), &device);
 149         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 150
 151         /* Open registry and look for network adapters */
 152
 153         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
 154                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 155                 return false;
 156         }
 157
 158         for (i = 0; ; i++) {
 159                 len = sizeof(adapterid);
 160                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 161                         break;
 162
 163                 /* Find out more about this adapter */
 164
 165                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
 166
 167                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 168                         continue;
 169
 170                 len = sizeof(adaptername);
 171                 RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 172
 173                 RegCloseKey(key2);
 174
 175                 if(device) {
 176                         if(!strcmp(device, adapterid)) {
 177                                 found = true;
 178                                 break;
 179                         } else
 180                                 continue;
 181                 }
 182
 183                 if(iface) {
 184                         if(!strcmp(iface, adaptername)) {
 185                                 found = true;
 186                                 break;
 187                         } else
 188                                 continue;
 189                 }
 190
 191                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 192                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 193                 if(device_handle != INVALID_HANDLE_VALUE) {
 194                         found = true;
 195                         break;
 196                 }
 197         }
 198
 199         RegCloseKey(key);
 200
 201         if(!found) {
 202                 logger(LOG_ERR, _("No Windows tap device found!"));
 203                 return false;
 204         }
 205
 206         if(!device)
 207                 device = xstrdup(adapterid);
 208
 209         if(!iface)
 210                 iface = xstrdup(adaptername);
 211
 212         /* Try to open the corresponding tap device */
 213
 214         if(device_handle == INVALID_HANDLE_VALUE) {
 215                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 216                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 217         }
 218
 219         if(device_handle == INVALID_HANDLE_VALUE) {
 220                 logger(LOG_ERR, _("%s (%s) is no a usable Windows tap device!"), device, iface);
 221                 return false;
 222         }
 223
 224         /* Get MAC address from tap device */
 225
 226         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 227                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device!"));
 228                 return false;
 229         }
 230
 231         if(routing_mode == RMODE_ROUTER) {
 232                 overwrite_mac = 1;
 233         }
 234
 235         /* Create a listening socket */
 236
 237         err = getaddrinfo(NULL, "12345", &hint, &ai);
 238
 239         if(err || !ai) {
 240                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 241                 return false;
 242         }
 243
 244         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 245
 246         if(sock < 0) {
 247                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 248                 return false;
 249         }
 250
 251         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 252                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 253                 return false;
 254         }
 255
 256         freeaddrinfo(ai);
 257
 258         if(listen(sock, 1)) {
 259                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 260                 return false;
 261         }
 262
 263         /* Start the tap reader */
 264
 265         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 266
 267         if(!thread) {
 268                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 269                 return false;
 270         }
 271
 272         /* Wait for the tap reader to connect back to us */
 273
 274         if((device_fd = accept(sock, NULL, 0)) == -1) {
 275                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 276                 return false;
 277         }
 278
 279         closesocket(sock);
 280
 281         device_info = _("Windows tap device");
 282
 283         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 284
 285         return true;
 286 }
 287
 288 void close_device(void)
 289 {
 290         cp();
 291
 292         CloseHandle(device_handle);
 293 }
 294
 295 bool read_packet(vpn_packet_t *packet)
 296 {
 297         int lenin;
 298
 299         cp();
 300
 301         if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
 302                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 303                            device, strerror(errno));
 304                 return false;
 305         }
 306
 307         packet->len = lenin;
 308
 309         device_total_in += packet->len;
 310
 311         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 312                            device_info);
 313
 314         return true;
 315 }
 316
 317 bool write_packet(vpn_packet_t *packet)
 318 {
 319         long lenout;
 320         OVERLAPPED overlapped = {0};
 321
 322         cp();
 323
 324         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 325                            packet->len, device_info);
 326
 327         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 328                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 329                 return false;
 330         }
 331
 332         device_total_out += packet->len;
 333
 334         return true;
 335 }
 336
 337 void dump_device_stats(void)
 338 {
 339         cp();
 340
 341         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 342         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 343         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 344 }