More generic handling of tap device under Windows.
[tinc] / src / mingw / device.c
1 /*
2     device.c -- Interaction with CIPE driver in a MinGW 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 1.1.2.3 2003/07/28 21:54:03 guus Exp $
21 */
22
23 #include "system.h"
24
25 #include <windows.h>
26 #include <winioctl.h>
27
28 #include "conf.h"
29 #include "logger.h"
30 #include "net.h"
31 #include "route.h"
32 #include "utils.h"
33 #include "xalloc.h"
34
35 #define NETCARD_REG_KEY_2000 "SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
36 #define NETCARD_REG_KEY      "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\NetworkCards"
37 #define REG_SERVICE_KEY      "SYSTEM\\CurrentControlSet\\Services"
38 #define REG_CONTROL_NET      "SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}"
39
40 #define USERMODEDEVICEDIR "\\\\.\\"
41 #define SYSDEVICEDIR  "\\Device\\"
42 #define USERDEVICEDIR "\\??\\"
43 #define TAPSUFFIX     ".tap"
44
45 #define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_PHYSICAL_NETCARD | 8000, request, method, FILE_ANY_ACCESS)
46
47 #define TAP_IOCTL_GET_LASTMAC    TAP_CONTROL_CODE(0, METHOD_BUFFERED)
48 #define TAP_IOCTL_GET_MAC        TAP_CONTROL_CODE(1, METHOD_BUFFERED)
49 #define TAP_IOCTL_SET_STATISTICS TAP_CONTROL_CODE(2, METHOD_BUFFERED)
50
51 /* FIXME: This only works for Windows 2000 */
52 #define OSTYPE 5
53
54 HANDLE device_fd = INVALID_HANDLE_VALUE;
55 char *device = NULL;
56 char *iface = NULL;
57 char *device_info = NULL;
58
59 int device_total_in = 0;
60 int device_total_out = 0;
61
62 bool setup_device(void)
63 {
64         HKEY key, key2;
65         int i;
66
67         char regpath[1024];
68         char adapterid[1024];
69         char adaptername[1024];
70         char tapname[1024];
71         char gelukt = 0;
72         long len;
73
74         bool found = false;
75
76         cp();
77
78         get_config_string(lookup_config(config_tree, "Device"), &device);
79         get_config_string(lookup_config(config_tree, "Interface"), &iface);
80
81         /* Open registry and look for network adapters */
82
83         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
84                 logger(LOG_ERR, _("Unable to read registry"));
85                 return false;
86         }
87
88         for (i = 0; ; i++) {
89                 len = sizeof(adapterid);
90                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
91                         break;
92
93                 if(device) {
94                         if(!strcmp(device, adapterid)) {
95                                 found = true;
96                                 break;
97                         } else
98                                 continue;
99                 }
100
101                 /* Find out more about this adapter */
102
103                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
104
105                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2)) {
106                         logger(LOG_ERR, _("Unable to read registry"));
107                         return false;
108                 }
109
110                 len = sizeof(adaptername);
111                 RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
112
113                 if(iface) {
114                         if(!strcmp(iface, adaptername)) {
115                                 found = true;
116                                 break;
117                         } else
118                                 continue;
119                 }
120
121                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
122                 device_fd = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
123                 if(device_fd != INVALID_HANDLE_VALUE) {
124                         found = true;
125                         break;
126                 }
127         }
128
129         if(!found) {
130                 logger(LOG_ERR, _("No Windows tap device found!"));
131                 return false;
132         }
133
134         device = adapterid;
135         iface = adaptername;
136
137         /* Try to open the corresponding tap device */
138
139         if(device_fd == INVALID_HANDLE_VALUE) {
140                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
141                 device_fd = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM, 0);
142         }
143         
144         if(device_fd == INVALID_HANDLE_VALUE) {
145                 logger(LOG_ERR, _("%s (%s) is no a usable Windows tap device!"), device, iface);
146                 return false;
147         }
148
149         /* Get MAC address from tap device */
150
151         if(DeviceIoControl(device_fd, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
152                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device!"));
153                 return false;
154         }
155
156         if(routing_mode == RMODE_ROUTER) {
157                 overwrite_mac = 1;
158         }
159
160         if(!get_config_string(lookup_config(config_tree, "Interface"), &iface))
161                 iface = device;
162
163         device_info = _("Windows tap device");
164
165         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
166
167         return true;
168 }
169
170 void close_device(void)
171 {
172         cp();
173
174         CloseHandle(device_fd);
175 }
176
177 bool read_packet(vpn_packet_t *packet)
178 {
179         int lenin;
180
181         cp();
182
183         if(!ReadFile(device_fd, packet->data, MTU, &lenin, NULL)) {
184                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
185                            device, strerror(errno));
186                 return false;
187         }
188         
189         packet->len = lenin;
190
191         device_total_in += packet->len;
192
193         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
194                            device_info);
195
196         return true;
197 }
198
199 bool write_packet(vpn_packet_t *packet)
200 {
201         int lenout;
202
203         cp();
204
205         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
206                            packet->len, device_info);
207
208         if(!WriteFile(device_fd, packet->data, packet->len, &lenout, NULL)) {
209                 logger(LOG_ERR, "Error while writing to %s %s", device_info, device);
210                 return false;
211         }
212
213         device_total_out += packet->len;
214
215         return true;
216 }
217
218 void dump_device_stats(void)
219 {
220         cp();
221
222         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
223         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
224         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
225 }