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 1.1.2.14 2003/10/08 11:37:53 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 #define TAP_IOCTL_GET_VERSION           TAP_CONTROL_CODE(3, METHOD_BUFFERED)
  47 #define TAP_IOCTL_GET_MTU               TAP_CONTROL_CODE(4, METHOD_BUFFERED)
  48 #define TAP_IOCTL_GET_INFO              TAP_CONTROL_CODE(5, METHOD_BUFFERED)
  49 #define TAP_IOCTL_CONFIG_POINT_TO_POINT TAP_CONTROL_CODE(6, METHOD_BUFFERED)
  50 #define TAP_IOCTL_SET_MEDIA_STATUS      TAP_CONTROL_CODE(7, METHOD_BUFFERED)
  51
  52
  53 int device_fd = 0;
  54 HANDLE device_handle = INVALID_HANDLE_VALUE;
  55 char *device = NULL;
  56 char *iface = NULL;
  57 char *device_info = NULL;
  58
  59 int device_total_in = 0;
  60 int device_total_out = 0;
  61
  62 extern char *myport;
  63
  64 DWORD WINAPI tapreader(void *bla) {
  65         int sock, err, status;
  66         struct addrinfo *ai;
  67         struct addrinfo hint = {
  68                 .ai_family = AF_UNSPEC,
  69                 .ai_socktype = SOCK_DGRAM,
  70                 .ai_protocol = IPPROTO_UDP,
  71                 .ai_flags = 0,
  72         };
  73         char buf[MTU];
  74         long len;
  75         OVERLAPPED overlapped;
  76
  77         /* Open a socket to the parent process */
  78
  79         err = getaddrinfo(NULL, myport, &hint, &ai);
  80
  81         if(err || !ai) {
  82                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
  83                 return -1;
  84         }
  85
  86         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
  87
  88         freeaddrinfo(ai);
  89
  90         if(sock < 0) {
  91                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  92                 return -1;
  93         }
  94
  95         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  96                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  97                 return -1;
  98         }
  99
 100         logger(LOG_DEBUG, _("Tap reader running"));
 101
 102         /* Read from tap device and send to parent */
 103
 104         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
 105
 106         for(;;) {
 107                 overlapped.Offset = 0;
 108                 overlapped.OffsetHigh = 0;
 109                 ResetEvent(overlapped.hEvent);
 110
 111                 status = ReadFile(device_handle, buf, sizeof(buf), &len, &overlapped);
 112
 113                 if(!status) {
 114                         if(GetLastError() == ERROR_IO_PENDING) {
 115                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 116                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 117                                         continue;
 118                         } else {
 119                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 120                                            device, strerror(errno));
 121                                 return -1;
 122                         }
 123                 }
 124
 125                 if(send(sock, buf, len, 0) <= 0)
 126                         return -1;
 127         }
 128 }
 129
 130 bool setup_device(void)
 131 {
 132         HKEY key, key2;
 133         int i;
 134
 135         char regpath[1024];
 136         char adapterid[1024];
 137         char adaptername[1024];
 138         char tapname[1024];
 139         long len;
 140         unsigned long status;
 141
 142         bool found = false;
 143
 144         int sock, err;
 145         HANDLE thread;
 146
 147         struct addrinfo *ai;
 148         struct addrinfo hint = {
 149                 .ai_family = AF_UNSPEC,
 150                 .ai_socktype = SOCK_DGRAM,
 151                 .ai_protocol = IPPROTO_UDP,
 152                 .ai_flags = 0,
 153         };
 154
 155         cp();
 156
 157         get_config_string(lookup_config(config_tree, "Device"), &device);
 158         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 159
 160         /* Open registry and look for network adapters */
 161
 162         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
 163                 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
 164                 return false;
 165         }
 166
 167         for (i = 0; ; i++) {
 168                 len = sizeof(adapterid);
 169                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 170                         break;
 171
 172                 /* Find out more about this adapter */
 173
 174                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
 175
 176                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 177                         continue;
 178
 179                 len = sizeof(adaptername);
 180                 err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 181
 182                 RegCloseKey(key2);
 183
 184                 if(err)
 185                         continue;
 186
 187                 if(device) {
 188                         if(!strcmp(device, adapterid)) {
 189                                 found = true;
 190                                 break;
 191                         } else
 192                                 continue;
 193                 }
 194
 195                 if(iface) {
 196                         if(!strcmp(iface, adaptername)) {
 197                                 found = true;
 198                                 break;
 199                         } else
 200                                 continue;
 201                 }
 202
 203                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 204                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 205                 if(device_handle != INVALID_HANDLE_VALUE) {
 206                         found = true;
 207                         break;
 208                 }
 209         }
 210
 211         RegCloseKey(key);
 212
 213         if(!found) {
 214                 logger(LOG_ERR, _("No Windows tap device found!"));
 215                 return false;
 216         }
 217
 218         if(!device)
 219                 device = xstrdup(adapterid);
 220
 221         if(!iface)
 222                 iface = xstrdup(adaptername);
 223
 224         /* Try to open the corresponding tap device */
 225
 226         if(device_handle == INVALID_HANDLE_VALUE) {
 227                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 228                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 229         }
 230
 231         if(device_handle == INVALID_HANDLE_VALUE) {
 232                 logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device: %s"), device, iface, winerror(GetLastError()));
 233                 return false;
 234         }
 235
 236         /* Get MAC address from tap device */
 237
 238         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 239                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
 240                 return false;
 241         }
 242
 243         if(routing_mode == RMODE_ROUTER) {
 244                 overwrite_mac = 1;
 245         }
 246
 247         /* Create a listening socket */
 248
 249         err = getaddrinfo(NULL, myport, &hint, &ai);
 250
 251         if(err || !ai) {
 252                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 253                 return false;
 254         }
 255
 256         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 257
 258         if(sock < 0) {
 259                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 260                 return false;
 261         }
 262
 263         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 264                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 265                 return false;
 266         }
 267
 268         freeaddrinfo(ai);
 269
 270         if(listen(sock, 1)) {
 271                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 272                 return false;
 273         }
 274
 275         /* Start the tap reader */
 276
 277         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 278
 279         if(!thread) {
 280                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 281                 return false;
 282         }
 283
 284         /* Wait for the tap reader to connect back to us */
 285
 286         if((device_fd = accept(sock, NULL, 0)) == -1) {
 287                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 288                 return false;
 289         }
 290
 291         closesocket(sock);
 292
 293         /* Set media status for newer TAP-Win32 devices */
 294
 295         status = true;
 296         DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof(status), &status, sizeof(status), &len, NULL);
 297
 298         device_info = _("Windows tap device");
 299
 300         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 301
 302         return true;
 303 }
 304
 305 void close_device(void)
 306 {
 307         cp();
 308
 309         CloseHandle(device_handle);
 310 }
 311
 312 bool read_packet(vpn_packet_t *packet)
 313 {
 314         int lenin;
 315
 316         cp();
 317
 318         if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
 319                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 320                            device, strerror(errno));
 321                 return false;
 322         }
 323
 324         packet->len = lenin;
 325
 326         device_total_in += packet->len;
 327
 328         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 329                            device_info);
 330
 331         return true;
 332 }
 333
 334 bool write_packet(vpn_packet_t *packet)
 335 {
 336         long lenout;
 337         OVERLAPPED overlapped = {0};
 338
 339         cp();
 340
 341         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 342                            packet->len, device_info);
 343
 344         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 345                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 346                 return false;
 347         }
 348
 349         device_total_out += packet->len;
 350
 351         return true;
 352 }
 353
 354 void dump_device_stats(void)
 355 {
 356         cp();
 357
 358         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 359         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 360         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 361 }