src/mingw/device.c

   1 /*
   2     device.c -- Interaction with Windows tap 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 1.1.2.6 2003/07/29 22:59:01 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 int device_fd = 0;
  55 HANDLE device_handle = INVALID_HANDLE_VALUE;
  56 char *device = NULL;
  57 char *iface = NULL;
  58 char *device_info = NULL;
  59
  60 int device_total_in = 0;
  61 int device_total_out = 0;
  62
  63 DWORD WINAPI tapreader(void *bla) {
  64         int sock, err, status;
  65         struct addrinfo *ai;
  66         struct addrinfo hint = {
  67                 .ai_family = AF_UNSPEC,
  68                 .ai_socktype = SOCK_DGRAM,
  69                 .ai_protocol = IPPROTO_UDP,
  70                 .ai_flags = 0,
  71         };
  72         char buf[MTU];
  73         long len;
  74         OVERLAPPED overlapped;
  75
  76         /* Open a socket to the parent process */
  77
  78         err = getaddrinfo(NULL, "12345", &hint, &ai);
  79
  80         if(err || !ai) {
  81                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
  82                 return -1;
  83         }
  84
  85         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
  86
  87         freeaddrinfo(ai);
  88
  89         if(sock < 0) {
  90                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
  91                 return -1;
  92         }
  93
  94         if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
  95                 logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
  96                 return -1;
  97         }
  98
  99         logger(LOG_DEBUG, _("Tap reader running"));
 100
 101         /* Read from tap device and send to parent */
 102
 103         overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
 104
 105         for(;;) {
 106                 overlapped.Offset = 0;
 107                 overlapped.OffsetHigh = 0;
 108                 ResetEvent(overlapped.hEvent);
 109
 110                 status = ReadFile(device_handle, buf, sizeof(buf), &len, &overlapped);
 111
 112                 if(!status) {
 113                         if(GetLastError() == ERROR_IO_PENDING) {
 114                                 WaitForSingleObject(overlapped.hEvent, INFINITE);
 115                                 if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
 116                                         continue;
 117                         } else {
 118                                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 119                                            device, strerror(errno));
 120                                 return -1;
 121                         }
 122                 }
 123
 124                 if(send(sock, buf, len, 0) <= 0)
 125                         return -1;
 126         }
 127 }
 128
 129 bool setup_device(void)
 130 {
 131         HKEY key, key2;
 132         int i;
 133
 134         char regpath[1024];
 135         char adapterid[1024];
 136         char adaptername[1024];
 137         char tapname[1024];
 138         long len;
 139
 140         bool found = false;
 141
 142         int sock, err;
 143         HANDLE thread;
 144
 145         struct addrinfo *ai;
 146         struct addrinfo hint = {
 147                 .ai_family = AF_UNSPEC,
 148                 .ai_socktype = SOCK_DGRAM,
 149                 .ai_protocol = IPPROTO_UDP,
 150                 .ai_flags = AI_PASSIVE,
 151         };
 152
 153         cp();
 154
 155         get_config_string(lookup_config(config_tree, "Device"), &device);
 156         get_config_string(lookup_config(config_tree, "Interface"), &iface);
 157
 158         /* Open registry and look for network adapters */
 159
 160         if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, REG_CONTROL_NET, 0, KEY_READ, &key)) {
 161                 logger(LOG_ERR, _("Unable to read registry"));
 162                 return false;
 163         }
 164
 165         for (i = 0; ; i++) {
 166                 len = sizeof(adapterid);
 167                 if(RegEnumKeyEx(key, i, adapterid, &len, 0, 0, 0, NULL))
 168                         break;
 169
 170                 /* Find out more about this adapter */
 171
 172                 snprintf(regpath, sizeof(regpath), "%s\\%s\\Connection", REG_CONTROL_NET, adapterid);
 173
 174                 if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
 175                         continue;
 176
 177                 len = sizeof(adaptername);
 178                 RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
 179
 180                 if(device) {
 181                         if(!strcmp(device, adapterid)) {
 182                                 found = true;
 183                                 break;
 184                         } else
 185                                 continue;
 186                 }
 187
 188                 if(iface) {
 189                         if(!strcmp(iface, adaptername)) {
 190                                 found = true;
 191                                 break;
 192                         } else
 193                                 continue;
 194                 }
 195
 196                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
 197                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 198                 if(device_handle != INVALID_HANDLE_VALUE) {
 199                         found = true;
 200                         break;
 201                 }
 202         }
 203
 204         if(!found) {
 205                 logger(LOG_ERR, _("No Windows tap device found!"));
 206                 return false;
 207         }
 208
 209         if(!device)
 210                 device = xstrdup(adapterid);
 211
 212         if(!iface)
 213                 iface = xstrdup(adaptername);
 214
 215         /* Try to open the corresponding tap device */
 216
 217         if(device_handle == INVALID_HANDLE_VALUE) {
 218                 snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
 219                 device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
 220         }
 221
 222         if(device_handle == INVALID_HANDLE_VALUE) {
 223                 logger(LOG_ERR, _("%s (%s) is no a usable Windows tap device!"), device, iface);
 224                 return false;
 225         }
 226
 227         /* Get MAC address from tap device */
 228
 229         if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof(mymac.x), mymac.x, sizeof(mymac.x), &len, 0)) {
 230                 logger(LOG_ERR, _("Could not get MAC address from Windows tap device!"));
 231                 return false;
 232         }
 233
 234         if(routing_mode == RMODE_ROUTER) {
 235                 overwrite_mac = 1;
 236         }
 237
 238         /* Create a listening socket */
 239
 240         err = getaddrinfo(NULL, "12345", &hint, &ai);
 241
 242         if(err || !ai) {
 243                 logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
 244                 return false;
 245         }
 246
 247         sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 248
 249         if(sock < 0) {
 250                 logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
 251                 return false;
 252         }
 253
 254         if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
 255                 logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
 256                 return false;
 257         }
 258
 259         freeaddrinfo(ai);
 260
 261         if(listen(sock, 1)) {
 262                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
 263                 return false;
 264         }
 265
 266         /* Start the tap reader */
 267
 268         thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
 269
 270         if(!thread) {
 271                 logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", strerror(errno));
 272                 return false;
 273         }
 274
 275         /* Wait for the tap reader to connect back to us */
 276
 277         if((device_fd = accept(sock, NULL, 0)) == -1) {
 278                 logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
 279                 return false;
 280         }
 281
 282         closesocket(sock);
 283
 284         device_info = _("Windows tap device");
 285
 286         logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
 287
 288         return true;
 289 }
 290
 291 void close_device(void)
 292 {
 293         cp();
 294
 295         CloseHandle(device_handle);
 296 }
 297
 298 bool read_packet(vpn_packet_t *packet)
 299 {
 300         int lenin;
 301
 302         cp();
 303
 304         if((lenin = recv(device_fd, packet->data, MTU, 0)) <= 0) {
 305                 logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
 306                            device, strerror(errno));
 307                 return false;
 308         }
 309
 310         packet->len = lenin;
 311
 312         device_total_in += packet->len;
 313
 314         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
 315                            device_info);
 316
 317         return true;
 318 }
 319
 320 bool write_packet(vpn_packet_t *packet)
 321 {
 322         long lenout;
 323         OVERLAPPED overlapped = {0};
 324
 325         cp();
 326
 327         ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
 328                            packet->len, device_info);
 329
 330         if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
 331                 logger(LOG_ERR, _("Error while writing to %s %s"), device_info, device);
 332                 return false;
 333         }
 334
 335         device_total_out += packet->len;
 336
 337         return true;
 338 }
 339
 340 void dump_device_stats(void)
 341 {
 342         cp();
 343
 344         logger(LOG_DEBUG, _("Statistics for %s %s:"), device_info, device);
 345         logger(LOG_DEBUG, _(" total bytes in:  %10d"), device_total_in);
 346         logger(LOG_DEBUG, _(" total bytes out: %10d"), device_total_out);
 347 }