tincd/cygwin/device.c

/*
    device.c -- Interaction with Windows tap driver in a Cygwin environment
    Copyright (C) 2002-2003 Ivo Timmermans <ivo@o2w.nl>,
                  2002-2003 Guus Sliepen <guus@sliepen.eu.org>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    $Id: device.c,v 1.1.2.16 2003/08/08 19:49:47 guus Exp $
*/


#include <w32api/windows.h>
#include <w32api/winioctl.h>


#define REG_CONTROL_NET "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"

#define USERMODEDEVICEDIR "\\\\.\\"
#define USERDEVICEDIR "\\??\\"
#define TAPSUFFIX ".tap"

#define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_PHYSICAL_NETCARD | 8000, request, method, FILE_ANY_ACCESS)

#define TAP_IOCTL_GET_LASTMAC    TAP_CONTROL_CODE(0, METHOD_BUFFERED)
#define TAP_IOCTL_GET_MAC        TAP_CONTROL_CODE(1, METHOD_BUFFERED)
#define TAP_IOCTL_SET_STATISTICS TAP_CONTROL_CODE(2, METHOD_BUFFERED)

int device_fd = -1;
static HANDLE device_handle = INVALID_HANDLE_VALUE;
char *device = NULL;
char *iface = NULL;
char *device_info = NULL;

int device_total_in = 0;
int device_total_out = 0;

pid_t reader_pid;
int sp[2];

bool setup_device(void)
{
        HKEY key, key2;
        int i;

        char regpath[1024];
        char adapterid[1024];
        char adaptername[1024];
        char tapname[1024];
        char gelukt = 0;
        long len;

        bool found = false;

        cp();

        get_config_string(lookup_config(config_tree, "Device"), &device);
        get_config_string(lookup_config(config_tree, "Interface"), &iface);

        /* Open registry and look for network adapters */

        if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
                logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
                return false;
        }

        for (i = 0; ; i++) {
                len = sizeof(adapterid);
                if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
                        break;

                /* Find out more about this adapter */

                snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);

                if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
                        continue;

                len = sizeof(adaptername);
                err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);

                RegCloseKey(key2);

                if(err)
                        continue;

                if(device) {
                        if(!strcmp(device, adapterid)) {
                                found = true;
                                break;
                        } else
                                continue;
                }

                if(iface) {
                        if(!strcmp(iface, adaptername)) {
                                found = true;
                                break;
                        } else
                                continue;
                }

                snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
                device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
                if(device_handle != INVALID_HANDLE_VALUE) {
                        CloseHandle(device_handle);
                        found = true;
                        break;
                }
        }

        RegCloseKey(key);

        if(!found) {
                logger(LOG_ERR, _("No Windows tap device found!"));
                return false;
        }

        if(!device)
                device = xstrdup(adapterid);

        if(!iface)
                iface = xstrdup(adaptername);

        snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
        
        /* Now we are going to open this device twice: once for reading and once for writing.
           We do this because apparently it isn't possible to check for activity in the select() loop.
           Furthermore I don't really know how to do it the "Windows" way. */

        if(socketpair(AF_UNIX, SOCK_DGRAM, PF_UNIX, sp)) {
                logger(LOG_DEBUG, _("System call `%s' failed: %s"), "socketpair", strerror(errno));
                return false;
        }

        /* The parent opens the tap device for writing. */
        
        device_handle = CreateFile(tapname, GENERIC_WRITE,  FILE_SHARE_READ,  0,  OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM , 0);
        
        if(device_handle == INVALID_HANDLE_VALUE) {
                logger(LOG_ERR, _("Could not open Windows tap device %s (%s) for writing: %s"), device, iface, winerror(GetLastError()));
                return false;
        }

        device_fd = sp[0];

        /* Get MAC address from tap device */

        if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
                logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
                return false;
        }

        if(routing_mode == RMODE_ROUTER) {
                overwrite_mac = 1;
        }

        /* Now we start the child */

        reader_pid = fork();

        if(reader_pid == -1) {
                logger(LOG_DEBUG, _("System call `%s' failed: %s"), "fork", strerror(errno));
                return false;
        }

        if(!reader_pid) {
                /* The child opens the tap device for reading, blocking.
                   It passes everything it reads to the socket. */
        
                char buf[MTU];
                long lenin;

                CloseHandle(device_handle);

                device_handle = CreateFile(tapname, GENERIC_READ, FILE_SHARE_WRITE, 0,  OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);

                if(device_handle == INVALID_HANDLE_VALUE) {
                        logger(LOG_ERR, _("Could not open Windows tap device %s (%s) for reading: %s"), device, iface, winerror(GetLastError()));
                        buf[0] = 0;
                        write(sp[1], buf, 1);
                        exit(1);
                }

                logger(LOG_DEBUG, _("Tap reader forked and running."));

                /* Notify success */

                buf[0] = 1;
                write(sp[1], buf, 1);

                /* Pass packets */

                for(;;) {
                        ReadFile(device_handle, buf, MTU, &lenin, NULL);
                        write(sp[1], buf, lenin);
                }
        }

        read(device_fd, &gelukt, 1);
        if(gelukt != 1) {
                logger(LOG_DEBUG, _("Tap reader failed!"));
                return false;
        }

        device_info = _("Windows tap device");

        logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);

        return true;
}

void close_device(void)
{
        cp();

        close(sp[0]);
        close(sp[1]);
        CloseHandle(device_handle);

        kill(reader_pid, SIGKILL);
}

bool read_packet(vpn_packet_t *packet)
{
        int lenin;

        cp();

        if((lenin = read(sp[0], packet->data, MTU)) <= 0) {
                logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
                           device, strerror(errno));
                return false;
        }
        
        packet->len = lenin;

        device_total_in += packet->len;

        ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
                           device_info);

        return true;
}

bool write_packet(vpn_packet_t *packet)
{
        long lenout;

        cp();

        ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
                           packet->len, device_info);

        if(!WriteFile (device_handle, packet->data, packet->len, &lenout, NULL)) {
                logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
                return false;
        }

        device_total_out += packet->len;

        return true;
}

void dump_device_stats(void)
{
        cp();

        logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
        logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
        logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
}
Revision:	1.1
Committed:	Tue Oct 14 03:22:09 2003 UTC (20 years, 8 months ago) by pcg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	poll-based-iom, VPE_1_2, VPE_1_4, VPE_1_6, rel-1_7, VPE-1_6_1
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/*
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>
5
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.
10
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.
15
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.
19
20			$Id: device.c,v 1.1.2.16 2003/08/08 19:49:47 guus Exp $
21			*/
22
23
24			#include <w32api/windows.h>
25			#include <w32api/winioctl.h>
26
27
28			#define REG_CONTROL_NET "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
29
30			#define USERMODEDEVICEDIR "\\\\.\\"
31			#define USERDEVICEDIR "\\??\\"
32			#define TAPSUFFIX ".tap"
33
34			#define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_PHYSICAL_NETCARD \| 8000, request, method, FILE_ANY_ACCESS)
35
36			#define TAP_IOCTL_GET_LASTMAC TAP_CONTROL_CODE(0, METHOD_BUFFERED)
37			#define TAP_IOCTL_GET_MAC TAP_CONTROL_CODE(1, METHOD_BUFFERED)
38			#define TAP_IOCTL_SET_STATISTICS TAP_CONTROL_CODE(2, METHOD_BUFFERED)
39
40			int device_fd = -1;
41			static HANDLE device_handle = INVALID_HANDLE_VALUE;
42			char *device = NULL;
43			char *iface = NULL;
44			char *device_info = NULL;
45
46			int device_total_in = 0;
47			int device_total_out = 0;
48
49			pid_t reader_pid;
50			int sp[2];
51
52			bool setup_device(void)
53			{
54			HKEY key, key2;
55			int i;
56
57			char regpath[1024];
58			char adapterid[1024];
59			char adaptername[1024];
60			char tapname[1024];
61			char gelukt = 0;
62			long len;
63
64			bool found = false;
65
66			cp();
67
68			get_config_string(lookup_config(config_tree, "Device"), &device);
69			get_config_string(lookup_config(config_tree, "Interface"), &iface);
70
71			/* Open registry and look for network adapters */
72
73			if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
74			logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
75			return false;
76			}
77
78			for (i = 0; ; i++) {
79			len = sizeof(adapterid);
80			if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
81			break;
82
83			/* Find out more about this adapter */
84
85			snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
86
87			if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
88			continue;
89
90			len = sizeof(adaptername);
91			err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
92
93			RegCloseKey(key2);
94
95			if(err)
96			continue;
97
98			if(device) {
99			if(!strcmp(device, adapterid)) {
100			found = true;
101			break;
102			} else
103			continue;
104			}
105
106			if(iface) {
107			if(!strcmp(iface, adaptername)) {
108			found = true;
109			break;
110			} else
111			continue;
112			}
113
114			snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
115			device_handle = CreateFile(tapname, GENERIC_WRITE \| GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
116			if(device_handle != INVALID_HANDLE_VALUE) {
117			CloseHandle(device_handle);
118			found = true;
119			break;
120			}
121			}
122
123			RegCloseKey(key);
124
125			if(!found) {
126			logger(LOG_ERR, _("No Windows tap device found!"));
127			return false;
128			}
129
130			if(!device)
131			device = xstrdup(adapterid);
132
133			if(!iface)
134			iface = xstrdup(adaptername);
135
136			snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
137
138			/* Now we are going to open this device twice: once for reading and once for writing.
139			We do this because apparently it isn't possible to check for activity in the select() loop.
140			Furthermore I don't really know how to do it the "Windows" way. */
141
142			if(socketpair(AF_UNIX, SOCK_DGRAM, PF_UNIX, sp)) {
143			logger(LOG_DEBUG, _("System call `%s' failed: %s"), "socketpair", strerror(errno));
144			return false;
145			}
146
147			/* The parent opens the tap device for writing. */
148
149			device_handle = CreateFile(tapname, GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM , 0);
150
151			if(device_handle == INVALID_HANDLE_VALUE) {
152			logger(LOG_ERR, _("Could not open Windows tap device %s (%s) for writing: %s"), device, iface, winerror(GetLastError()));
153			return false;
154			}
155
156			device_fd = sp[0];
157
158			/* Get MAC address from tap device */
159
160			if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
161			logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
162			return false;
163			}
164
165			if(routing_mode == RMODE_ROUTER) {
166			overwrite_mac = 1;
167			}
168
169			/* Now we start the child */
170
171			reader_pid = fork();
172
173			if(reader_pid == -1) {
174			logger(LOG_DEBUG, _("System call `%s' failed: %s"), "fork", strerror(errno));
175			return false;
176			}
177
178			if(!reader_pid) {
179			/* The child opens the tap device for reading, blocking.
180			It passes everything it reads to the socket. */
181
182			char buf[MTU];
183			long lenin;
184
185			CloseHandle(device_handle);
186
187			device_handle = CreateFile(tapname, GENERIC_READ, FILE_SHARE_WRITE, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
188
189			if(device_handle == INVALID_HANDLE_VALUE) {
190			logger(LOG_ERR, _("Could not open Windows tap device %s (%s) for reading: %s"), device, iface, winerror(GetLastError()));
191			buf[0] = 0;
192			write(sp[1], buf, 1);
193			exit(1);
194			}
195
196			logger(LOG_DEBUG, _("Tap reader forked and running."));
197
198			/* Notify success */
199
200			buf[0] = 1;
201			write(sp[1], buf, 1);
202
203			/* Pass packets */
204
205			for(;;) {
206			ReadFile(device_handle, buf, MTU, &lenin, NULL);
207			write(sp[1], buf, lenin);
208			}
209			}
210
211			read(device_fd, &gelukt, 1);
212			if(gelukt != 1) {
213			logger(LOG_DEBUG, _("Tap reader failed!"));
214			return false;
215			}
216
217			device_info = _("Windows tap device");
218
219			logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
220
221			return true;
222			}
223
224			void close_device(void)
225			{
226			cp();
227
228			close(sp[0]);
229			close(sp[1]);
230			CloseHandle(device_handle);
231
232			kill(reader_pid, SIGKILL);
233			}
234
235			bool read_packet(vpn_packet_t *packet)
236			{
237			int lenin;
238
239			cp();
240
241			if((lenin = read(sp[0], packet->data, MTU)) <= 0) {
242			logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
243			device, strerror(errno));
244			return false;
245			}
246
247			packet->len = lenin;
248
249			device_total_in += packet->len;
250
251			ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
252			device_info);
253
254			return true;
255			}
256
257			bool write_packet(vpn_packet_t *packet)
258			{
259			long lenout;
260
261			cp();
262
263			ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
264			packet->len, device_info);
265
266			if(!WriteFile (device_handle, packet->data, packet->len, &lenout, NULL)) {
267			logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
268			return false;
269			}
270
271			device_total_out += packet->len;
272
273			return true;
274			}
275
276			void dump_device_stats(void)
277			{
278			cp();
279
280			logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
281			logger(LOG_DEBUG, _(" total bytes in: %10d"), device_total_in);
282			logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
283			}