tincd/cygwin/device.c

/*
    device.c -- Interaction with Windows tap driver in a Cygwin environment
    Copyright (C) 2002-2004 Ivo Timmermans <ivo@tinc-vpn.org>,
                  2002-2004 Guus Sliepen <guus@tinc-vpn.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 1400 2004-11-01 17:02:19Z guus $
*/

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

#include "mingw/common.h"

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

static int device_total_in = 0;
static int device_total_out = 0;

static pid_t reader_pid;
static int sp[2];

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

        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, NETWORK_CONNECTIONS_KEY, 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", NETWORK_CONNECTIONS_KEY, 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:	1.2
Committed:	Thu Mar 17 23:59:37 2005 UTC (19 years, 3 months ago) by pcg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-1_9, rel-1_8, rel-2_01, rel-3_0, rel-2_2, rel-2_0, rel-2_21, rel-2_22, rel-2_25, HEAD
Changes since 1.1:	+11 -23 lines
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	pcg	1.2	Copyright (C) 2002-2004 Ivo Timmermans <ivo@tinc-vpn.org>,
4			2002-2004 Guus Sliepen <guus@tinc-vpn.org>
5	pcg	1.1
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	pcg	1.2	$Id: device.c 1400 2004-11-01 17:02:19Z guus $
21	pcg	1.1	*/
22
23			#include <w32api/windows.h>
24			#include <w32api/winioctl.h>
25
26	pcg	1.2	#include "mingw/common.h"
27	pcg	1.1
28			int device_fd = -1;
29			static HANDLE device_handle = INVALID_HANDLE_VALUE;
30			char *device = NULL;
31			char *iface = NULL;
32			char *device_info = NULL;
33
34	pcg	1.2	static int device_total_in = 0;
35			static int device_total_out = 0;
36	pcg	1.1
37	pcg	1.2	static pid_t reader_pid;
38			static int sp[2];
39	pcg	1.1
40			bool setup_device(void)
41			{
42			HKEY key, key2;
43	pcg	1.2	int i, err;
44	pcg	1.1
45			char regpath[1024];
46			char adapterid[1024];
47			char adaptername[1024];
48			char tapname[1024];
49			char gelukt = 0;
50			long len;
51
52			bool found = false;
53
54			cp();
55
56			get_config_string(lookup_config(config_tree, "Device"), &device);
57			get_config_string(lookup_config(config_tree, "Interface"), &iface);
58
59			/* Open registry and look for network adapters */
60
61	pcg	1.2	if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
62	pcg	1.1	logger(LOG_ERR, _("Unable to read registry: %s"), winerror(GetLastError()));
63			return false;
64			}
65
66			for (i = 0; ; i++) {
67			len = sizeof(adapterid);
68			if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
69			break;
70
71			/* Find out more about this adapter */
72
73	pcg	1.2	snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
74	pcg	1.1
75			if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
76			continue;
77
78			len = sizeof(adaptername);
79			err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
80
81			RegCloseKey(key2);
82
83			if(err)
84			continue;
85
86			if(device) {
87			if(!strcmp(device, adapterid)) {
88			found = true;
89			break;
90			} else
91			continue;
92			}
93
94			if(iface) {
95			if(!strcmp(iface, adaptername)) {
96			found = true;
97			break;
98			} else
99			continue;
100			}
101
102			snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
103			device_handle = CreateFile(tapname, GENERIC_WRITE \| GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
104			if(device_handle != INVALID_HANDLE_VALUE) {
105			CloseHandle(device_handle);
106			found = true;
107			break;
108			}
109			}
110
111			RegCloseKey(key);
112
113			if(!found) {
114			logger(LOG_ERR, _("No Windows tap device found!"));
115			return false;
116			}
117
118			if(!device)
119			device = xstrdup(adapterid);
120
121			if(!iface)
122			iface = xstrdup(adaptername);
123
124			snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
125
126			/* Now we are going to open this device twice: once for reading and once for writing.
127			We do this because apparently it isn't possible to check for activity in the select() loop.
128			Furthermore I don't really know how to do it the "Windows" way. */
129
130			if(socketpair(AF_UNIX, SOCK_DGRAM, PF_UNIX, sp)) {
131			logger(LOG_DEBUG, _("System call `%s' failed: %s"), "socketpair", strerror(errno));
132			return false;
133			}
134
135			/* The parent opens the tap device for writing. */
136
137			device_handle = CreateFile(tapname, GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM , 0);
138
139			if(device_handle == INVALID_HANDLE_VALUE) {
140			logger(LOG_ERR, _("Could not open Windows tap device %s (%s) for writing: %s"), device, iface, winerror(GetLastError()));
141			return false;
142			}
143
144			device_fd = sp[0];
145
146			/* Get MAC address from tap device */
147
148			if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
149			logger(LOG_ERR, _("Could not get MAC address from Windows tap device %s (%s): %s"), device, iface, winerror(GetLastError()));
150			return false;
151			}
152
153			if(routing_mode == RMODE_ROUTER) {
154			overwrite_mac = 1;
155			}
156
157			/* Now we start the child */
158
159			reader_pid = fork();
160
161			if(reader_pid == -1) {
162			logger(LOG_DEBUG, _("System call `%s' failed: %s"), "fork", strerror(errno));
163			return false;
164			}
165
166			if(!reader_pid) {
167			/* The child opens the tap device for reading, blocking.
168			It passes everything it reads to the socket. */
169
170			char buf[MTU];
171			long lenin;
172
173			CloseHandle(device_handle);
174
175			device_handle = CreateFile(tapname, GENERIC_READ, FILE_SHARE_WRITE, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
176
177			if(device_handle == INVALID_HANDLE_VALUE) {
178			logger(LOG_ERR, _("Could not open Windows tap device %s (%s) for reading: %s"), device, iface, winerror(GetLastError()));
179			buf[0] = 0;
180			write(sp[1], buf, 1);
181			exit(1);
182			}
183
184			logger(LOG_DEBUG, _("Tap reader forked and running."));
185
186			/* Notify success */
187
188			buf[0] = 1;
189			write(sp[1], buf, 1);
190
191			/* Pass packets */
192
193			for(;;) {
194			ReadFile(device_handle, buf, MTU, &lenin, NULL);
195			write(sp[1], buf, lenin);
196			}
197			}
198
199			read(device_fd, &gelukt, 1);
200			if(gelukt != 1) {
201			logger(LOG_DEBUG, _("Tap reader failed!"));
202			return false;
203			}
204
205			device_info = _("Windows tap device");
206
207			logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
208
209			return true;
210			}
211
212			void close_device(void)
213			{
214			cp();
215
216			close(sp[0]);
217			close(sp[1]);
218			CloseHandle(device_handle);
219
220			kill(reader_pid, SIGKILL);
221			}
222
223			bool read_packet(vpn_packet_t *packet)
224			{
225			int lenin;
226
227			cp();
228
229			if((lenin = read(sp[0], packet->data, MTU)) <= 0) {
230			logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
231			device, strerror(errno));
232			return false;
233			}
234
235			packet->len = lenin;
236
237			device_total_in += packet->len;
238
239			ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
240			device_info);
241
242			return true;
243			}
244
245			bool write_packet(vpn_packet_t *packet)
246			{
247			long lenout;
248
249			cp();
250
251			ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
252			packet->len, device_info);
253
254			if(!WriteFile (device_handle, packet->data, packet->len, &lenout, NULL)) {
255			logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
256			return false;
257			}
258
259			device_total_out += packet->len;
260
261			return true;
262			}
263
264			void dump_device_stats(void)
265			{
266			cp();
267
268			logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
269			logger(LOG_DEBUG, _(" total bytes in: %10d"), device_total_in);
270			logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
271			}