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;
52 int status = ReadFile(device_handle, (void *)device_read_packet.data, MTU, NULL, &device_read_overlapped);
54 if(!status && GetLastError() != ERROR_IO_PENDING) {
55 logger(DEBUG_ALWAYS, LOG_ERR, "Error while reading from %s %s: %s", device_info,
56 device, strerror(errno));
60 static void device_handle_read(void *data, int flags) {
61 ResetEvent(device_read_overlapped.hEvent);
64 if (!GetOverlappedResult(device_handle, &device_read_overlapped, &len, FALSE)) {
65 logger(DEBUG_ALWAYS, LOG_ERR, "Error getting read result from %s %s: %s", device_info,
66 device, strerror(errno));
70 device_read_packet.len = len;
71 device_read_packet.priority = 0;
72 route(myself, &device_read_packet);
76 static bool setup_device(void) {
82 char adaptername[1024];
90 get_config_string(lookup_config(config_tree, "Device"), &device);
91 get_config_string(lookup_config(config_tree, "Interface"), &iface);
93 /* Open registry and look for network adapters */
95 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
96 logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read registry: %s", winerror(GetLastError()));
101 len = sizeof adapterid;
102 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
105 /* Find out more about this adapter */
107 snprintf(regpath, sizeof regpath, "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
109 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
112 len = sizeof adaptername;
113 err = RegQueryValueEx(key2, "Name", 0, 0, (LPBYTE)adaptername, &len);
121 if(!strcmp(device, adapterid)) {
129 if(!strcmp(iface, adaptername)) {
136 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
137 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
138 if(device_handle != INVALID_HANDLE_VALUE) {
147 logger(DEBUG_ALWAYS, LOG_ERR, "No Windows tap device found!");
152 device = xstrdup(adapterid);
155 iface = xstrdup(adaptername);
157 /* Try to open the corresponding tap device */
159 if(device_handle == INVALID_HANDLE_VALUE) {
160 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
161 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
164 if(device_handle == INVALID_HANDLE_VALUE) {
165 logger(DEBUG_ALWAYS, LOG_ERR, "%s (%s) is not a usable Windows tap device: %s", device, iface, winerror(GetLastError()));
169 /* Get MAC address from tap device */
171 if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof mymac.x, mymac.x, sizeof mymac.x, &len, 0)) {
172 logger(DEBUG_ALWAYS, LOG_ERR, "Could not get MAC address from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
176 if(routing_mode == RMODE_ROUTER) {
180 /* Start the tap reader */
182 io_add_event(&device_read_io, device_handle_read, NULL, CreateEvent(NULL, TRUE, FALSE, NULL));
183 device_read_overlapped.hEvent = device_read_io.event;
186 device_info = "Windows tap device";
188 logger(DEBUG_ALWAYS, LOG_INFO, "%s (%s) is a %s", device, iface, device_info);
193 static void enable_device(void) {
194 logger(DEBUG_ALWAYS, LOG_INFO, "Enabling %s", device_info);
197 DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
200 static void disable_device(void) {
201 logger(DEBUG_ALWAYS, LOG_INFO, "Disabling %s", device_info);
204 DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
207 static void close_device(void) {
208 io_del(&device_read_io);
209 CancelIo(device_handle);
210 CloseHandle(device_read_overlapped.hEvent);
211 CloseHandle(device_handle); device_handle = INVALID_HANDLE_VALUE;
213 free(device); device = NULL;
214 free(iface); iface = NULL;
218 static bool read_packet(vpn_packet_t *packet) {
222 static bool write_packet(vpn_packet_t *packet) {
224 OVERLAPPED overlapped = {0};
226 logger(DEBUG_TRAFFIC, LOG_DEBUG, "Writing packet of %d bytes to %s",
227 packet->len, device_info);
229 if(!WriteFile(device_handle, packet->data, packet->len, &outlen, &overlapped)) {
230 logger(DEBUG_ALWAYS, LOG_ERR, "Error while writing to %s %s: %s", device_info, device, winerror(GetLastError()));
237 const devops_t os_devops = {
238 .setup = setup_device,
239 .close = close_device,
241 .write = write_packet,
242 .enable = enable_device,
243 .disable = disable_device,