2 device.c -- Interaction with Windows tap driver in a MinGW environment
3 Copyright (C) 2002-2005 Ivo Timmermans,
4 2002-2013 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;
39 static io_t device_read_io;
40 static OVERLAPPED device_read_overlapped;
41 static vpn_packet_t device_read_packet;
44 static char *device_info = NULL;
48 static void device_issue_read() {
49 device_read_overlapped.Offset = 0;
50 device_read_overlapped.OffsetHigh = 0;
55 status = ReadFile(device_handle, (void *)device_read_packet.data, MTU, &len, &device_read_overlapped);
57 if (GetLastError() != ERROR_IO_PENDING)
58 logger(DEBUG_ALWAYS, LOG_ERR, "Error while reading from %s %s: %s", device_info,
59 device, strerror(errno));
63 device_read_packet.len = len;
64 device_read_packet.priority = 0;
65 route(myself, &device_read_packet);
69 static void device_handle_read(void *data, int flags) {
70 ResetEvent(device_read_overlapped.hEvent);
73 if (!GetOverlappedResult(device_handle, &device_read_overlapped, &len, FALSE)) {
74 logger(DEBUG_ALWAYS, LOG_ERR, "Error getting read result from %s %s: %s", device_info,
75 device, strerror(errno));
79 device_read_packet.len = len;
80 device_read_packet.priority = 0;
81 route(myself, &device_read_packet);
85 static bool setup_device(void) {
91 char adaptername[1024];
99 get_config_string(lookup_config(config_tree, "Device"), &device);
100 get_config_string(lookup_config(config_tree, "Interface"), &iface);
102 /* Open registry and look for network adapters */
104 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
105 logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read registry: %s", winerror(GetLastError()));
110 len = sizeof adapterid;
111 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
114 /* Find out more about this adapter */
116 snprintf(regpath, sizeof regpath, "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
118 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
121 len = sizeof adaptername;
122 err = RegQueryValueEx(key2, "Name", 0, 0, (LPBYTE)adaptername, &len);
130 if(!strcmp(device, adapterid)) {
138 if(!strcmp(iface, adaptername)) {
145 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
146 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
147 if(device_handle != INVALID_HANDLE_VALUE) {
156 logger(DEBUG_ALWAYS, LOG_ERR, "No Windows tap device found!");
161 device = xstrdup(adapterid);
164 iface = xstrdup(adaptername);
166 /* Try to open the corresponding tap device */
168 if(device_handle == INVALID_HANDLE_VALUE) {
169 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
170 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
173 if(device_handle == INVALID_HANDLE_VALUE) {
174 logger(DEBUG_ALWAYS, LOG_ERR, "%s (%s) is not a usable Windows tap device: %s", device, iface, winerror(GetLastError()));
178 /* Get MAC address from tap device */
180 if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof mymac.x, mymac.x, sizeof mymac.x, &len, 0)) {
181 logger(DEBUG_ALWAYS, LOG_ERR, "Could not get MAC address from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
185 if(routing_mode == RMODE_ROUTER) {
189 device_info = "Windows tap device";
191 logger(DEBUG_ALWAYS, LOG_INFO, "%s (%s) is a %s", device, iface, device_info);
196 static void enable_device(void) {
197 logger(DEBUG_ALWAYS, LOG_INFO, "Enabling %s", device_info);
201 DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
203 io_add_event(&device_read_io, device_handle_read, NULL, CreateEvent(NULL, TRUE, FALSE, NULL));
204 device_read_overlapped.hEvent = device_read_io.event;
208 static void disable_device(void) {
209 logger(DEBUG_ALWAYS, LOG_INFO, "Disabling %s", device_info);
211 io_del(&device_read_io);
212 CancelIo(device_handle);
213 CloseHandle(device_read_overlapped.hEvent);
217 DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
220 static void close_device(void) {
221 CloseHandle(device_handle); device_handle = INVALID_HANDLE_VALUE;
223 free(device); device = NULL;
224 free(iface); iface = NULL;
228 static bool read_packet(vpn_packet_t *packet) {
232 static bool write_packet(vpn_packet_t *packet) {
234 OVERLAPPED overlapped = {0};
236 logger(DEBUG_TRAFFIC, LOG_DEBUG, "Writing packet of %d bytes to %s",
237 packet->len, device_info);
239 if(!WriteFile(device_handle, packet->data, packet->len, &outlen, &overlapped)) {
240 logger(DEBUG_ALWAYS, LOG_ERR, "Error while writing to %s %s: %s", device_info, device, winerror(GetLastError()));
247 const devops_t os_devops = {
248 .setup = setup_device,
249 .close = close_device,
251 .write = write_packet,
252 .enable = enable_device,
253 .disable = disable_device,