2 device.c -- Interaction with Windows tap driver in a MinGW environment
3 Copyright (C) 2002-2005 Ivo Timmermans,
4 2002-2014 Guus Sliepen <guus@tinc-vpn.org>
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.
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.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 #include "../system.h"
27 #include "../device.h"
28 #include "../logger.h"
33 #include "../xalloc.h"
38 static HANDLE device_handle = INVALID_HANDLE_VALUE;
41 static char *device_info = NULL;
45 static DWORD WINAPI tapreader(void *bla) {
48 OVERLAPPED overlapped;
52 logger(DEBUG_ALWAYS, LOG_DEBUG, "Tap reader running");
54 /* Read from tap device and send to parent */
56 overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
59 overlapped.Offset = 0;
60 overlapped.OffsetHigh = 0;
61 ResetEvent(overlapped.hEvent);
63 status = ReadFile(device_handle, (void *)packet.data, MTU, &len, &overlapped);
66 if(GetLastError() == ERROR_IO_PENDING) {
67 WaitForSingleObject(overlapped.hEvent, INFINITE);
68 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
71 logger(DEBUG_ALWAYS, LOG_ERR, "Error while reading from %s %s: %s", device_info,
72 device, strerror(errno));
75 EnterCriticalSection(&mutex);
77 LeaveCriticalSection(&mutex);
88 EnterCriticalSection(&mutex);
89 route(myself, &packet);
91 LeaveCriticalSection(&mutex);
95 static bool setup_device(void) {
100 char adapterid[1024];
101 char adaptername[1024];
104 unsigned long status;
111 get_config_string(lookup_config(config_tree, "Device"), &device);
112 get_config_string(lookup_config(config_tree, "Interface"), &iface);
114 /* Open registry and look for network adapters */
116 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
117 logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read registry: %s", winerror(GetLastError()));
122 len = sizeof adapterid;
123 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
126 /* Find out more about this adapter */
128 snprintf(regpath, sizeof regpath, "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
130 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
133 len = sizeof adaptername;
134 err = RegQueryValueEx(key2, "Name", 0, 0, (LPBYTE)adaptername, &len);
142 if(!strcmp(device, adapterid)) {
150 if(!strcmp(iface, adaptername)) {
157 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
158 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
159 if(device_handle != INVALID_HANDLE_VALUE) {
168 logger(DEBUG_ALWAYS, LOG_ERR, "No Windows tap device found!");
173 device = xstrdup(adapterid);
176 iface = xstrdup(adaptername);
178 /* Try to open the corresponding tap device */
180 if(device_handle == INVALID_HANDLE_VALUE) {
181 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
182 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
185 if(device_handle == INVALID_HANDLE_VALUE) {
186 logger(DEBUG_ALWAYS, LOG_ERR, "%s (%s) is not a usable Windows tap device: %s", device, iface, winerror(GetLastError()));
190 /* Get MAC address from tap device */
192 if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof mymac.x, mymac.x, sizeof mymac.x, &len, 0)) {
193 logger(DEBUG_ALWAYS, LOG_ERR, "Could not get MAC address from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
197 if(routing_mode == RMODE_ROUTER) {
201 /* Start the tap reader */
203 thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
206 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "CreateThread", winerror(GetLastError()));
210 /* Set media status for newer TAP-Win32 devices */
213 DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
215 device_info = "Windows tap device";
217 logger(DEBUG_ALWAYS, LOG_INFO, "%s (%s) is a %s", device, iface, device_info);
222 static void close_device(void) {
223 CloseHandle(device_handle);
229 static bool read_packet(vpn_packet_t *packet) {
233 static bool write_packet(vpn_packet_t *packet) {
235 OVERLAPPED overlapped = {0};
237 logger(DEBUG_TRAFFIC, LOG_DEBUG, "Writing packet of %d bytes to %s",
238 packet->len, device_info);
240 if(!WriteFile(device_handle, packet->data, packet->len, &outlen, &overlapped)) {
241 logger(DEBUG_ALWAYS, LOG_ERR, "Error while writing to %s %s: %s", device_info, device, winerror(GetLastError()));
248 const devops_t os_devops = {
249 .setup = setup_device,
250 .close = close_device,
252 .write = write_packet,