2 device.c -- Interaction with Windows tap driver in a Cygwin 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"
23 #include <w32api/windows.h>
24 #include <w32api/winioctl.h>
27 #include "../device.h"
28 #include "../logger.h"
33 #include "../xalloc.h"
35 #include "../mingw/common.h"
38 static HANDLE device_handle = INVALID_HANDLE_VALUE;
41 static char *device_info = NULL;
43 static uint64_t device_total_in = 0;
44 static uint64_t device_total_out = 0;
46 static pid_t reader_pid;
49 static bool setup_device(void) {
55 char adaptername[1024];
62 get_config_string(lookup_config(config_tree, "Device"), &device);
63 get_config_string(lookup_config(config_tree, "Interface"), &iface);
65 /* Open registry and look for network adapters */
67 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
68 logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read registry: %s", winerror(GetLastError()));
73 len = sizeof adapterid;
74 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
77 /* Find out more about this adapter */
79 snprintf(regpath, sizeof regpath, "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
81 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
84 len = sizeof adaptername;
85 err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
93 if(!strcmp(device, adapterid)) {
101 if(!strcmp(iface, adaptername)) {
108 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
109 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
110 if(device_handle != INVALID_HANDLE_VALUE) {
111 CloseHandle(device_handle);
120 logger(DEBUG_ALWAYS, LOG_ERR, "No Windows tap device found!");
125 device = xstrdup(adapterid);
128 iface = xstrdup(adaptername);
130 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
132 /* Now we are going to open this device twice: once for reading and once for writing.
133 We do this because apparently it isn't possible to check for activity in the select() loop.
134 Furthermore I don't really know how to do it the "Windows" way. */
136 if(socketpair(AF_UNIX, SOCK_DGRAM, PF_UNIX, sp)) {
137 logger(DEBUG_ALWAYS, LOG_DEBUG, "System call `%s' failed: %s", "socketpair", strerror(errno));
141 /* The parent opens the tap device for writing. */
143 device_handle = CreateFile(tapname, GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM , 0);
145 if(device_handle == INVALID_HANDLE_VALUE) {
146 logger(DEBUG_ALWAYS, LOG_ERR, "Could not open Windows tap device %s (%s) for writing: %s", device, iface, winerror(GetLastError()));
152 /* Get MAC address from tap device */
154 if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof mymac.x, mymac.x, sizeof mymac.x, &len, 0)) {
155 logger(DEBUG_ALWAYS, LOG_ERR, "Could not get MAC address from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
159 if(routing_mode == RMODE_ROUTER) {
163 /* Now we start the child */
167 if(reader_pid == -1) {
168 logger(DEBUG_ALWAYS, LOG_DEBUG, "System call `%s' failed: %s", "fork", strerror(errno));
173 /* The child opens the tap device for reading, blocking.
174 It passes everything it reads to the socket. */
179 CloseHandle(device_handle);
181 device_handle = CreateFile(tapname, GENERIC_READ, FILE_SHARE_WRITE, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
183 if(device_handle == INVALID_HANDLE_VALUE) {
184 logger(DEBUG_ALWAYS, LOG_ERR, "Could not open Windows tap device %s (%s) for reading: %s", device, iface, winerror(GetLastError()));
186 write(sp[1], buf, 1);
190 logger(DEBUG_ALWAYS, LOG_DEBUG, "Tap reader forked and running.");
195 write(sp[1], buf, 1);
200 ReadFile(device_handle, buf, MTU, &inlen, NULL);
201 write(sp[1], buf, inlen);
205 read(device_fd, &gelukt, 1);
207 logger(DEBUG_ALWAYS, LOG_DEBUG, "Tap reader failed!");
211 device_info = "Windows tap device";
213 logger(DEBUG_ALWAYS, LOG_INFO, "%s (%s) is a %s", device, iface, device_info);
218 static void close_device(void) {
221 CloseHandle(device_handle);
223 kill(reader_pid, SIGKILL);
229 static bool read_packet(vpn_packet_t *packet) {
232 if((inlen = read(sp[0], packet->data, MTU)) <= 0) {
233 logger(DEBUG_ALWAYS, LOG_ERR, "Error while reading from %s %s: %s", device_info,
234 device, strerror(errno));
240 device_total_in += packet->len;
242 logger(DEBUG_TRAFFIC, LOG_DEBUG, "Read packet of %d bytes from %s", packet->len,
248 static bool write_packet(vpn_packet_t *packet) {
251 logger(DEBUG_TRAFFIC, LOG_DEBUG, "Writing packet of %d bytes to %s",
252 packet->len, device_info);
254 if(!WriteFile (device_handle, packet->data, packet->len, &outlen, NULL)) {
255 logger(DEBUG_ALWAYS, LOG_ERR, "Error while writing to %s %s: %s", device_info, device, winerror(GetLastError()));
259 device_total_out += packet->len;
264 static void dump_device_stats(void) {
265 logger(DEBUG_ALWAYS, LOG_DEBUG, "Statistics for %s %s:", device_info, device);
266 logger(DEBUG_ALWAYS, LOG_DEBUG, " total bytes in: %10"PRIu64, device_total_in);
267 logger(DEBUG_ALWAYS, LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
270 const devops_t os_devops = {
271 .setup = setup_device,
272 .close = close_device,
274 .write = write_packet,
275 .dump_stats = dump_device_stats,