tinc-vpn.org Git - tinc/blob - 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 1.1.2.9 2003/08/02 21:01:50 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 NETCARD_REG_KEY_2000 "SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
  36 #define NETCARD_REG_KEY      "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\NetworkCards"
  37 #define REG_SERVICE_KEY      "SYSTEM\\CurrentControlSet\\Services"
  38 #define REG_CONTROL_NET      "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
  39
  40 #define USERMODEDEVICEDIR "\\\\.\\"
  41 #define SYSDEVICEDIR  "\\Device\\"
  42 #define USERDEVICEDIR "\\??\\"
  43 #define TAPSUFFIX     ".tap"
  44
  45 #define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_PHYSICAL_NETCARD | 8000, request, method, FILE_ANY_ACCESS)
  46
  47 #define TAP_IOCTL_GET_LASTMAC    TAP_CONTROL_CODE(0, METHOD_BUFFERED)
  48 #define TAP_IOCTL_GET_MAC        TAP_CONTROL_CODE(1, METHOD_BUFFERED)
  49 #define TAP_IOCTL_SET_STATISTICS TAP_CONTROL_CODE(2, METHOD_BUFFERED)
  50
  51 /* FIXME: This only works for Windows 2000 */
  52 #define OSTYPE 5
  53
  54 int device_fd = 0;
  55 HANDLE device_handle = INVALID_HANDLE_VALUE;
  56 char *device = NULL;
  57 char *iface = NULL;
  58 char *device_info = NULL;
  59
  60 int device_total_in = 0;
  61 int device_total_out = 0;
  62
  63 DWORD WINAPI tapreader(void *bla) {
  64         int sock, err, status;
  65         struct addrinfo *ai;
  66         struct addrinfo hint = {
  67                 .ai_family = AF_UNSPEC,
  68                 .ai_socktype = SOCK_DGRAM,
  69                 .ai_protocol = IPPROTO_UDP,
  70                 .ai_flags = 0,
  71         };
  72         char buf[MTU];
  73         long len;
  74         OVERLAPPED overlapped;
  75
  76         /* Open a socket to the parent process */
  77
  78         err = getaddrinfo(NULL, "12345", &hint, &ai);
  79
  80         if(err || !ai) {
  81                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
  82                 return -1;
  83         }
  84
  85         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
  86
  87         freeaddrinfo(ai);
  88
  89         if(sock < 0) {
  90                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  91                 return -1;
  92         }
  93
  94         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  95                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  96                 return -1;
  97         }
  98
  99         logger(LOG_DEBUG, _("Tap reader running"));
 100
 101         /* Read from tap device and send to parent */
 102
 103         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
 104
 105         for(;;) {
 106                 overlapped.Offset = 0;
 107                 overlapped.OffsetHigh = 0;
 108                 ResetEvent(overlapped.hEvent);
 109
 110                 status = ReadFile(device_handle, buf, sizeof(buf), &len, &overlapped);
 111
 112                 if(!status) {
 113                         if(GetLastError() == ERROR_IO_PENDING) {
 114                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 115                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 116                                         continue;
 117                         } else {
 118                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 119                                            device, strerror(errno));
 120                                 return -1;
 121                         }
 122                 }
 123
 124                 if(send(sock, buf, len, 0) <= 0)
 125                         return -1;
 126         }
 127 }
 128
 129 bool setup_device(void)
 130 {
 131         HKEY key, key2;
 132         int i;
 133
 134         char regpath[1024];
 135         char adapterid[1024];
 136         char adaptername[1024];
 137         char tapname[1024];
 138         long len;
 139
 140         bool found = false;
 141
 142         int sock, err;
 143         HANDLE thread;
 144
 145         struct addrinfo *ai;
 146         struct addrinfo hint = {
 147                 .ai_family = AF_UNSPEC,
 148                 .ai_socktype = SOCK_DGRAM,
 149                 .ai_protocol = IPPROTO_UDP,
 150                 .ai_flags = AI_PASSIVE,
 151         };
 152
 153         cp();
 154
 155         get_config_string(lookup_config(config_tree, "Device"), &device);
 156         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 157
 158         /* Open registry and look for network adapters */
 159
 160         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
 161                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 162                 return false;
 163         }
 164
 165         for (i = 0; ; i++) {
 166                 len = sizeof(adapterid);
 167                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 168                         break;
 169
 170                 /* Find out more about this adapter */
 171
 172                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
 173
 174                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 175                         continue;
 176
 177                 len = sizeof(adaptername);
 178                 RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 179
 180                 RegCloseKey(key2);
 181
 182                 if(device) {
 183                         if(!strcmp(device, adapterid)) {
 184                                 found = true;
 185                                 break;
 186                         } else
 187                                 continue;
 188                 }
 189
 190                 if(iface) {
 191                         if(!strcmp(iface, adaptername)) {
 192                                 found = true;
 193                                 break;
 194                         } else
 195                                 continue;
 196                 }
 197
 198                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 199                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 200                 if(device_handle != INVALID_HANDLE_VALUE) {
 201                         found = true;
 202                         break;
 203                 }
 204         }
 205
 206         RegCloseKey(key);
 207
 208         if(!found) {
 209                 logger(LOG_ERR, _("No Windows tap device found!"));
 210                 return false;
 211         }
 212
 213         if(!device)
 214                 device = xstrdup(adapterid);
 215
 216         if(!iface)
 217                 iface = xstrdup(adaptername);
 218
 219         /* Try to open the corresponding tap device */
 220
 221         if(device_handle == INVALID_HANDLE_VALUE) {
 222                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 223                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 224         }
 225
 226         if(device_handle == INVALID_HANDLE_VALUE) {
 227                 logger(LOG_ERR, _("%s (%s) is no a usable Windows tap device!"), device, iface);
 228                 return false;
 229         }
 230
 231         /* Get MAC address from tap device */
 232
 233         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 234                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device!"));
 235                 return false;
 236         }
 237
 238         if(routing_mode == RMODE_ROUTER) {
 239                 overwrite_mac = 1;
 240         }
 241
 242         /* Create a listening socket */
 243
 244         err = getaddrinfo(NULL, "12345", &hint, &ai);
 245
 246         if(err || !ai) {
 247                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 248                 return false;
 249         }
 250
 251         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 252
 253         if(sock < 0) {
 254                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 255                 return false;
 256         }
 257
 258         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 259                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 260                 return false;
 261         }
 262
 263         freeaddrinfo(ai);
 264
 265         if(listen(sock, 1)) {
 266                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 267                 return false;
 268         }
 269
 270         /* Start the tap reader */
 271
 272         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 273
 274         if(!thread) {
 275                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 276                 return false;
 277         }
 278
 279         /* Wait for the tap reader to connect back to us */
 280
 281         if((device_fd = accept(sock, NULL, 0)) == -1) {
 282                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 283                 return false;
 284         }
 285
 286         closesocket(sock);
 287
 288         device_info = _("Windows tap device");
 289
 290         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 291
 292         return true;
 293 }
 294
 295 void close_device(void)
 296 {
 297         cp();
 298
 299         CloseHandle(device_handle);
 300 }
 301
 302 bool read_packet(vpn_packet_t *packet)
 303 {
 304         int lenin;
 305
 306         cp();
 307
 308         if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
 309                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 310                            device, strerror(errno));
 311                 return false;
 312         }
 313
 314         packet->len = lenin;
 315
 316         device_total_in += packet->len;
 317
 318         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 319                            device_info);
 320
 321         return true;
 322 }
 323
 324 bool write_packet(vpn_packet_t *packet)
 325 {
 326         long lenout;
 327         OVERLAPPED overlapped = {0};
 328
 329         cp();
 330
 331         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 332                            packet->len, device_info);
 333
 334         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 335                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 336                 return false;
 337         }
 338
 339         device_total_out += packet->len;
 340
 341         return true;
 342 }
 343
 344 void dump_device_stats(void)
 345 {
 346         cp();
 347
 348         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 349         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 350         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 351 }