2 device.c -- Interaction with Windows tap driver in a Cygwin environment
3 Copyright (C) 2002-2003 Ivo Timmermans <ivo@o2w.nl>,
4 2002-2003 Guus Sliepen <guus@sliepen.eu.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
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 $Id: device.c,v 1.1.2.15 2003/08/02 21:33:18 guus Exp $
25 #include <w32api/windows.h>
26 #include <w32api/winioctl.h>
35 #define REG_CONTROL_NET "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
37 #define USERMODEDEVICEDIR "\\\\.\\"
38 #define USERDEVICEDIR "\\??\\"
39 #define TAPSUFFIX ".tap"
41 #define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_PHYSICAL_NETCARD | 8000, request, method, FILE_ANY_ACCESS)
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)
48 static HANDLE device_handle = INVALID_HANDLE_VALUE;
51 char *device_info = NULL;
53 int device_total_in = 0;
54 int device_total_out = 0;
59 bool setup_device(void)
66 char adaptername[1024];
75 get_config_string(lookup_config(config_tree, "Device"), &device);
76 get_config_string(lookup_config(config_tree, "Interface"), &iface);
78 /* Open registry and look for network adapters */
80 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
81 logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
86 len = sizeof(adapterid);
87 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
90 /* Find out more about this adapter */
92 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
94 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
97 len = sizeof(adaptername);
98 RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
103 if(!strcmp(device, adapterid)) {
111 if(!strcmp(iface, adaptername)) {
118 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
119 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
120 if(device_handle != INVALID_HANDLE_VALUE) {
121 CloseHandle(device_handle);
130 logger(LOG_ERR, _("No Windows tap device found!"));
135 device = xstrdup(adapterid);
138 iface = xstrdup(adaptername);
140 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
142 /* Now we are going to open this device twice: once for reading and once for writing.
143 We do this because apparently it isn't possible to check for activity in the select() loop.
144 Furthermore I don't really know how to do it the "Windows" way. */
146 if(socketpair(AF_UNIX, SOCK_DGRAM, PF_UNIX, sp)) {
147 logger(LOG_DEBUG, _("System call `%s' failed: %s"), "socketpair", strerror(errno));
151 /* The parent opens the tap device for writing. */
153 device_handle = CreateFile(tapname, GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM , 0);
155 if(device_handle == INVALID_HANDLE_VALUE) {
156 logger(LOG_ERR, _("Could not open Windows tap device for writing: %s"), winerror(GetLastError()));
162 /* Get MAC address from tap device */
164 if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
165 logger(LOG_ERR, _("Could not get MAC address from Windows tap device: %s"), winerror(GetLastError()));
169 if(routing_mode == RMODE_ROUTER) {
173 /* Now we start the child */
177 if(reader_pid == -1) {
178 logger(LOG_DEBUG, _("System call `%s' failed: %s"), "fork", strerror(errno));
183 /* The child opens the tap device for reading, blocking.
184 It passes everything it reads to the socket. */
189 CloseHandle(device_handle);
191 device_handle = CreateFile(tapname, GENERIC_READ, FILE_SHARE_WRITE, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
193 if(device_handle == INVALID_HANDLE_VALUE) {
194 logger(LOG_ERR, _("Could not open Windows tap device for reading: %s"), winerror(GetLastError()));
196 write(sp[1], buf, 1);
200 logger(LOG_DEBUG, _("Tap reader forked and running."));
205 write(sp[1], buf, 1);
210 ReadFile(device_handle, buf, MTU, &lenin, NULL);
211 write(sp[1], buf, lenin);
215 read(device_fd, &gelukt, 1);
217 logger(LOG_DEBUG, _("Tap reader failed!"));
221 device_info = _("Windows tap device");
223 logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
228 void close_device(void)
234 CloseHandle(device_handle);
236 kill(reader_pid, SIGKILL);
239 bool read_packet(vpn_packet_t *packet)
245 if((lenin = read(sp[0], packet->data, MTU)) <= 0) {
246 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
247 device, strerror(errno));
253 device_total_in += packet->len;
255 ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
261 bool write_packet(vpn_packet_t *packet)
267 ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
268 packet->len, device_info);
270 if(!WriteFile (device_handle, packet->data, packet->len, &lenout, NULL)) {
271 logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
275 device_total_out += packet->len;
280 void dump_device_stats(void)
284 logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
285 logger(LOG_DEBUG, _(" total bytes in: %10d"), device_total_in);
286 logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);