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 1.1.2.12 2003/08/08 17:20:12 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                 RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 174
 175                 RegCloseKey(key2);
 176
 177                 if(device) {
 178                         if(!strcmp(device, adapterid)) {
 179                                 found = true;
 180                                 break;
 181                         } else
 182                                 continue;
 183                 }
 184
 185                 if(iface) {
 186                         if(!strcmp(iface, adaptername)) {
 187                                 found = true;
 188                                 break;
 189                         } else
 190                                 continue;
 191                 }
 192
 193                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 194                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 195                 if(device_handle != INVALID_HANDLE_VALUE) {
 196                         found = true;
 197                         break;
 198                 }
 199         }
 200
 201         RegCloseKey(key);
 202
 203         if(!found) {
 204                 logger(LOG_ERR, _("No Windows tap device found!"));
 205                 return false;
 206         }
 207
 208         if(!device)
 209                 device = xstrdup(adapterid);
 210
 211         if(!iface)
 212                 iface = xstrdup(adaptername);
 213
 214         /* Try to open the corresponding tap device */
 215
 216         if(device_handle == INVALID_HANDLE_VALUE) {
 217                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 218                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 219         }
 220
 221         if(device_handle == INVALID_HANDLE_VALUE) {
 222                 logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device!"), device, iface);
 223                 return false;
 224         }
 225
 226         /* Get MAC address from tap device */
 227
 228         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 229                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device!"));
 230                 return false;
 231         }
 232
 233         if(routing_mode == RMODE_ROUTER) {
 234                 overwrite_mac = 1;
 235         }
 236
 237         /* Create a listening socket */
 238
 239         err = getaddrinfo(NULL, myport, &hint, &ai);
 240
 241         if(err || !ai) {
 242                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 243                 return false;
 244         }
 245
 246         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 247
 248         if(sock < 0) {
 249                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 250                 return false;
 251         }
 252
 253         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 254                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 255                 return false;
 256         }
 257
 258         freeaddrinfo(ai);
 259
 260         if(listen(sock, 1)) {
 261                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 262                 return false;
 263         }
 264
 265         /* Start the tap reader */
 266
 267         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 268
 269         if(!thread) {
 270                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
 271                 return false;
 272         }
 273
 274         /* Wait for the tap reader to connect back to us */
 275
 276         if((device_fd = accept(sock, NULL, 0)) == -1) {
 277                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 278                 return false;
 279         }
 280
 281         closesocket(sock);
 282
 283         device_info = _("Windows tap device");
 284
 285         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 286
 287         return true;
 288 }
 289
 290 void close_device(void)
 291 {
 292         cp();
 293
 294         CloseHandle(device_handle);
 295 }
 296
 297 bool read_packet(vpn_packet_t *packet)
 298 {
 299         int lenin;
 300
 301         cp();
 302
 303         if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
 304                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 305                            device, strerror(errno));
 306                 return false;
 307         }
 308
 309         packet->len = lenin;
 310
 311         device_total_in += packet->len;
 312
 313         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 314                            device_info);
 315
 316         return true;
 317 }
 318
 319 bool write_packet(vpn_packet_t *packet)
 320 {
 321         long lenout;
 322         OVERLAPPED overlapped = {0};
 323
 324         cp();
 325
 326         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 327                            packet->len, device_info);
 328
 329         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 330                 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
 331                 return false;
 332         }
 333
 334         device_total_out += packet->len;
 335
 336         return true;
 337 }
 338
 339 void dump_device_stats(void)
 340 {
 341         cp();
 342
 343         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 344         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 345         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 346 }