]> git.meshlink.io Git - meshlink/blob - src/mingw/device.c
Fix compiler warnings on Windows.
[meshlink] / src / mingw / device.c
1 /*
2     device.c -- Interaction with Windows tap driver in a MinGW environment
3     Copyright (C) 2002-2005 Ivo Timmermans,
4                   2002-2013 Guus Sliepen <guus@tinc-vpn.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 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.
19 */
20
21 #include "system.h"
22
23 #include <windows.h>
24 #include <winioctl.h>
25
26 #include "conf.h"
27 #include "device.h"
28 #include "logger.h"
29 #include "names.h"
30 #include "net.h"
31 #include "route.h"
32 #include "utils.h"
33 #include "xalloc.h"
34
35 #include "mingw/common.h"
36
37 int device_fd = -1;
38 static HANDLE device_handle = INVALID_HANDLE_VALUE;
39 char *device = NULL;
40 char *iface = NULL;
41 static char *device_info = NULL;
42
43 static uint64_t device_total_in = 0;
44 static uint64_t device_total_out = 0;
45
46 extern char *myport;
47
48 static DWORD WINAPI tapreader(void *bla) {
49         int status;
50         DWORD len;
51         OVERLAPPED overlapped;
52         vpn_packet_t packet;
53
54         logger(DEBUG_ALWAYS, LOG_DEBUG, "Tap reader running");
55
56         /* Read from tap device and send to parent */
57
58         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
59
60         for(;;) {
61                 overlapped.Offset = 0;
62                 overlapped.OffsetHigh = 0;
63                 ResetEvent(overlapped.hEvent);
64
65                 status = ReadFile(device_handle, (void *)packet.data, MTU, &len, &overlapped);
66
67                 if(!status) {
68                         if(GetLastError() == ERROR_IO_PENDING) {
69                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
70                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
71                                         continue;
72                         } else {
73                                 logger(DEBUG_ALWAYS, LOG_ERR, "Error while reading from %s %s: %s", device_info,
74                                            device, strerror(errno));
75                                 return -1;
76                         }
77                 }
78
79                 EnterCriticalSection(&mutex);
80                 packet.len = len;
81                 packet.priority = 0;
82                 route(myself, &packet);
83                 LeaveCriticalSection(&mutex);
84         }
85 }
86
87 static bool setup_device(void) {
88         HKEY key, key2;
89         int i;
90
91         char regpath[1024];
92         char adapterid[1024];
93         char adaptername[1024];
94         char tapname[1024];
95         DWORD len;
96         unsigned long status;
97
98         bool found = false;
99
100         int err;
101         HANDLE thread;
102
103         get_config_string(lookup_config(config_tree, "Device"), &device);
104         get_config_string(lookup_config(config_tree, "Interface"), &iface);
105
106         /* Open registry and look for network adapters */
107
108         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {
109                 logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read registry: %s", winerror(GetLastError()));
110                 return false;
111         }
112
113         for (i = 0; ; i++) {
114                 len = sizeof adapterid;
115                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
116                         break;
117
118                 /* Find out more about this adapter */
119
120                 snprintf(regpath, sizeof regpath, "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
121
122                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
123                         continue;
124
125                 len = sizeof adaptername;
126                 err = RegQueryValueEx(key2, "Name", 0, 0, (LPBYTE)adaptername, &len);
127
128                 RegCloseKey(key2);
129
130                 if(err)
131                         continue;
132
133                 if(device) {
134                         if(!strcmp(device, adapterid)) {
135                                 found = true;
136                                 break;
137                         } else
138                                 continue;
139                 }
140
141                 if(iface) {
142                         if(!strcmp(iface, adaptername)) {
143                                 found = true;
144                                 break;
145                         } else
146                                 continue;
147                 }
148
149                 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
150                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
151                 if(device_handle != INVALID_HANDLE_VALUE) {
152                         found = true;
153                         break;
154                 }
155         }
156
157         RegCloseKey(key);
158
159         if(!found) {
160                 logger(DEBUG_ALWAYS, LOG_ERR, "No Windows tap device found!");
161                 return false;
162         }
163
164         if(!device)
165                 device = xstrdup(adapterid);
166
167         if(!iface)
168                 iface = xstrdup(adaptername);
169
170         /* Try to open the corresponding tap device */
171
172         if(device_handle == INVALID_HANDLE_VALUE) {
173                 snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
174                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
175         }
176
177         if(device_handle == INVALID_HANDLE_VALUE) {
178                 logger(DEBUG_ALWAYS, LOG_ERR, "%s (%s) is not a usable Windows tap device: %s", device, iface, winerror(GetLastError()));
179                 return false;
180         }
181
182         /* Get MAC address from tap device */
183
184         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof mymac.x, mymac.x, sizeof mymac.x, &len, 0)) {
185                 logger(DEBUG_ALWAYS, LOG_ERR, "Could not get MAC address from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
186                 return false;
187         }
188
189         if(routing_mode == RMODE_ROUTER) {
190                 overwrite_mac = 1;
191         }
192
193         /* Start the tap reader */
194
195         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
196
197         if(!thread) {
198                 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "CreateThread", winerror(GetLastError()));
199                 return false;
200         }
201
202         /* Set media status for newer TAP-Win32 devices */
203
204         status = true;
205         DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
206
207         device_info = "Windows tap device";
208
209         logger(DEBUG_ALWAYS, LOG_INFO, "%s (%s) is a %s", device, iface, device_info);
210
211         return true;
212 }
213
214 static void close_device(void) {
215         CloseHandle(device_handle);
216
217         free(device);
218         free(iface);
219 }
220
221 static bool read_packet(vpn_packet_t *packet) {
222         return false;
223 }
224
225 static bool write_packet(vpn_packet_t *packet) {
226         DWORD outlen;
227         OVERLAPPED overlapped = {0};
228
229         logger(DEBUG_TRAFFIC, LOG_DEBUG, "Writing packet of %d bytes to %s",
230                            packet->len, device_info);
231
232         if(!WriteFile(device_handle, packet->data, packet->len, &outlen, &overlapped)) {
233                 logger(DEBUG_ALWAYS, LOG_ERR, "Error while writing to %s %s: %s", device_info, device, winerror(GetLastError()));
234                 return false;
235         }
236
237         device_total_out += packet->len;
238
239         return true;
240 }
241
242 static void dump_device_stats(void) {
243         logger(DEBUG_ALWAYS, LOG_DEBUG, "Statistics for %s %s:", device_info, device);
244         logger(DEBUG_ALWAYS, LOG_DEBUG, " total bytes in:  %10"PRIu64, device_total_in);
245         logger(DEBUG_ALWAYS, LOG_DEBUG, " total bytes out: %10"PRIu64, device_total_out);
246 }
247
248 const devops_t os_devops = {
249         .setup = setup_device,
250         .close = close_device,
251         .read = read_packet,
252         .write = write_packet,
253         .dump_stats = dump_device_stats,
254 };