Fix compiling under MinGW.
[tinc] / src / mingw / device.c
index 004249c..b047615 100644 (file)
@@ -1,7 +1,7 @@
 /*
     device.c -- Interaction with Windows tap driver in a MinGW environment
     Copyright (C) 2002-2005 Ivo Timmermans,
-                  2002-2006 Guus Sliepen <guus@tinc-vpn.org>
+                  2002-2014 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
     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.
-
-    $Id$
+    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.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-#include "system.h"
+#include "../system.h"
 
 #include <windows.h>
 #include <winioctl.h>
 
-#include "conf.h"
-#include "logger.h"
-#include "net.h"
-#include "route.h"
-#include "utils.h"
-#include "xalloc.h"
+#include "../conf.h"
+#include "../device.h"
+#include "../logger.h"
+#include "../names.h"
+#include "../net.h"
+#include "../route.h"
+#include "../utils.h"
+#include "../xalloc.h"
 
-#include "mingw/common.h"
+#include "common.h"
 
-int device_fd = 0;
+int device_fd = -1;
 static HANDLE device_handle = INVALID_HANDLE_VALUE;
+static io_t device_read_io;
+static OVERLAPPED device_read_overlapped;
+static OVERLAPPED device_write_overlapped;
+static vpn_packet_t device_read_packet;
+static vpn_packet_t device_write_packet;
 char *device = NULL;
 char *iface = NULL;
-char *device_info = NULL;
-
-static int device_total_in = 0;
-static int device_total_out = 0;
+static char *device_info = NULL;
 
 extern char *myport;
 
-static struct packetbuf {
-       uint8_t data[MTU];
-       length_t len;
-} *bufs;
-
-static int nbufs = 64;
-
-DWORD WINAPI tapreader(void *bla) {
-       int sock, err, status;
-       struct addrinfo *ai;
-       struct addrinfo hint = {
-               .ai_family = AF_UNSPEC,
-               .ai_socktype = SOCK_STREAM,
-               .ai_protocol = IPPROTO_TCP,
-               .ai_flags = 0,
-       };
-       unsigned char bufno = 0;
-       long len;
-       OVERLAPPED overlapped;
-
-       /* Open a socket to the parent process */
-
-       err = getaddrinfo(NULL, myport, &hint, &ai);
-
-       if(err || !ai) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
-               return -1;
-       }
-
-       sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
-
-       freeaddrinfo(ai);
-
-       if(sock < 0) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
-               return -1;
-       }
+static void device_issue_read() {
+       device_read_overlapped.Offset = 0;
+       device_read_overlapped.OffsetHigh = 0;
+
+       int status;
+       for (;;) {
+               DWORD len;
+               status = ReadFile(device_handle, (void *)device_read_packet.data, MTU, &len, &device_read_overlapped);
+               if (!status) {
+                       if (GetLastError() != ERROR_IO_PENDING)
+                               logger(DEBUG_ALWAYS, LOG_ERR, "Error while reading from %s %s: %s", device_info,
+                                          device, strerror(errno));
+                       break;
+               }
 
-       if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "connect", strerror(errno));
-               return -1;
+               device_read_packet.len = len;
+               device_read_packet.priority = 0;
+               route(myself, &device_read_packet);
        }
+}
 
-       logger(LOG_DEBUG, _("Tap reader running"));
-
-       /* Read from tap device and send to parent */
-
-       overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
-       
-       for(;;) {
-               overlapped.Offset = 0;
-               overlapped.OffsetHigh = 0;
-               ResetEvent(overlapped.hEvent);
-
-               status = ReadFile(device_handle, bufs[bufno].data, MTU, &len, &overlapped);
-
-               if(!status) {
-                       if(GetLastError() == ERROR_IO_PENDING) {
-                               WaitForSingleObject(overlapped.hEvent, INFINITE);
-                               if(!GetOverlappedResult(device_handle, &overlapped, &len, FALSE))
-                                       continue;
-                       } else {
-                               logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
-                                          device, strerror(errno));
-                               return -1;
-                       }
-               }
+static void device_handle_read(void *data, int flags) {
+       ResetEvent(device_read_overlapped.hEvent);
 
-               bufs[bufno].len = len;
-               if(send(sock, &bufno, 1, 0) <= 0)
-                       return -1;
-               if(++bufno >= nbufs)
-                       bufno = 0;
+       DWORD len;
+       if (!GetOverlappedResult(device_handle, &device_read_overlapped, &len, FALSE)) {
+               logger(DEBUG_ALWAYS, LOG_ERR, "Error getting read result from %s %s: %s", device_info,
+                          device, strerror(errno));
+               return;
        }
+
+       device_read_packet.len = len;
+       device_read_packet.priority = 0;
+       route(myself, &device_read_packet);
+       device_issue_read();
 }
 
-bool setup_device(void)
-{
+static bool setup_device(void) {
        HKEY key, key2;
        int i;
 
@@ -130,48 +92,39 @@ bool setup_device(void)
        char adapterid[1024];
        char adaptername[1024];
        char tapname[1024];
-       long len;
-       unsigned long status;
+       DWORD len;
 
        bool found = false;
 
-       int sock, err;
-       HANDLE thread;
-
-       struct addrinfo *ai;
-       struct addrinfo hint = {
-               .ai_family = AF_UNSPEC,
-               .ai_socktype = SOCK_STREAM,
-               .ai_protocol = IPPROTO_TCP,
-               .ai_flags = AI_PASSIVE,
-       };
-
-       cp();
+       int err;
 
        get_config_string(lookup_config(config_tree, "Device"), &device);
        get_config_string(lookup_config(config_tree, "Interface"), &iface);
 
+       if(device && iface)
+               logger(DEBUG_ALWAYS, LOG_WARNING, "Warning: both Device and Interface specified, results may not be as expected");
+
        /* 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()));
+               logger(DEBUG_ALWAYS, LOG_ERR, "Unable to read registry: %s", winerror(GetLastError()));
                return false;
        }
 
        for (i = 0; ; i++) {
-               len = sizeof(adapterid);
+               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);
+               snprintf(regpath, sizeof regpath, "%s\\%s\\Connection", NETWORK_CONNECTIONS_KEY, adapterid);
 
-                if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
+               if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, regpath, 0, KEY_READ, &key2))
                        continue;
 
-               len = sizeof(adaptername);
-               err = RegQueryValueEx(key2, "Name", 0, 0, adaptername, &len);
+               len = sizeof adaptername;
+               err = RegQueryValueEx(key2, "Name", 0, 0, (LPBYTE)adaptername, &len);
 
                RegCloseKey(key2);
 
@@ -194,7 +147,7 @@ bool setup_device(void)
                                continue;
                }
 
-               snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
+               snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, adapterid);
                device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
                if(device_handle != INVALID_HANDLE_VALUE) {
                        found = true;
@@ -205,7 +158,7 @@ bool setup_device(void)
        RegCloseKey(key);
 
        if(!found) {
-               logger(LOG_ERR, _("No Windows tap device found!"));
+               logger(DEBUG_ALWAYS, LOG_ERR, "No Windows tap device found!");
                return false;
        }
 
@@ -218,19 +171,38 @@ bool setup_device(void)
        /* Try to open the corresponding tap device */
 
        if(device_handle == INVALID_HANDLE_VALUE) {
-               snprintf(tapname, sizeof(tapname), USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
+               snprintf(tapname, sizeof tapname, USERMODEDEVICEDIR "%s" TAPSUFFIX, device);
                device_handle = CreateFile(tapname, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, 0);
        }
-       
+
        if(device_handle == INVALID_HANDLE_VALUE) {
-               logger(LOG_ERR, _("%s (%s) is not a usable Windows tap device: %s"), device, iface, winerror(GetLastError()));
+               logger(DEBUG_ALWAYS, LOG_ERR, "%s (%s) is not a usable Windows tap device: %s", device, iface, winerror(GetLastError()));
                return false;
        }
 
+       /* Get version information from tap device */
+
+       {
+               ULONG info[3] = {0};
+               DWORD len;
+               if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_VERSION, &info, sizeof info, &info, sizeof info, &len, NULL))
+                       logger(DEBUG_ALWAYS, LOG_WARNING, "Could not get version information from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
+               else {
+                       logger(DEBUG_ALWAYS, LOG_INFO, "TAP-Windows driver version: %lu.%lu%s", info[0], info[1], info[2] ? " (DEBUG)" : "");
+
+                       /* Warn if using >=9.21. This is because starting from 9.21, TAP-Win32 seems to use a different, less efficient write path. */
+                       if(info[0] == 9 && info[1] >= 21)
+                               logger(DEBUG_ALWAYS, LOG_WARNING,
+                                       "You are using the newer (>= 9.0.0.21, NDIS6) series of TAP-Win32 drivers. "
+                                       "Using these drivers with tinc is not recommanded as it can result in poor performance. "
+                                       "You might want to revert back to 9.0.0.9 instead.");
+               }
+       }
+
        /* 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()));
+       if(!DeviceIoControl(device_handle, TAP_IOCTL_GET_MAC, mymac.x, sizeof mymac.x, mymac.x, sizeof mymac.x, &len, 0)) {
+               logger(DEBUG_ALWAYS, LOG_ERR, "Could not get MAC address from Windows tap device %s (%s): %s", device, iface, winerror(GetLastError()));
                return false;
        }
 
@@ -238,129 +210,102 @@ bool setup_device(void)
                overwrite_mac = 1;
        }
 
-       /* Set up ringbuffer */
-
-       get_config_int(lookup_config(config_tree, "RingBufferSize"), &nbufs);
-       if(nbufs <= 1)
-               nbufs = 1;
-       else if(nbufs > 256)
-               nbufs = 256;
-       
-       bufs = xmalloc_and_zero(nbufs * sizeof *bufs);
-
-       /* Create a listening socket */
-
-       err = getaddrinfo(NULL, myport, &hint, &ai);
-
-       if(err || !ai) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "getaddrinfo", gai_strerror(errno));
-               return false;
-       }
-
-       sock = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
-
-       if(sock < 0) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "socket", strerror(errno));
-               return false;
-       }
-
-       if(bind(sock, ai->ai_addr, ai->ai_addrlen)) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "bind", strerror(errno));
-               return false;
-       }
+       device_info = "Windows tap device";
 
-       freeaddrinfo(ai);
+       logger(DEBUG_ALWAYS, LOG_INFO, "%s (%s) is a %s", device, iface, device_info);
 
-       if(listen(sock, 1)) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
-               return false;
-       }
+       return true;
+}
 
-       /* Start the tap reader */
+static void enable_device(void) {
+       logger(DEBUG_ALWAYS, LOG_INFO, "Enabling %s", device_info);
 
-       thread = CreateThread(NULL, 0, tapreader, NULL, 0, NULL);
+       ULONG status = 1;
+       DWORD len;
+       DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
 
-       if(!thread) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "CreateThread", winerror(GetLastError()));
-               return false;
-       }
+       /* We don't use the write event directly, but GetOverlappedResult() does, internally. */
 
-       /* Wait for the tap reader to connect back to us */
+       device_read_overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
+       device_write_overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
 
-       if((device_fd = accept(sock, NULL, 0)) == -1) {
-               logger(LOG_ERR, _("System call `%s' failed: %s"), "accept", strerror(errno));
-               return false;
-       }
+       io_add_event(&device_read_io, device_handle_read, NULL, device_read_overlapped.hEvent);
+       device_issue_read();
+}
 
-       closesocket(sock);
+static void disable_device(void) {
+       logger(DEBUG_ALWAYS, LOG_INFO, "Disabling %s", device_info);
 
-       /* Set media status for newer TAP-Win32 devices */
+       io_del(&device_read_io);
+       CancelIo(device_handle);
 
-       status = true;
-       DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof(status), &status, sizeof(status), &len, NULL);
+       /* According to MSDN, CancelIo() does not necessarily wait for the operation to complete.
+          To prevent race conditions, make sure the operation is complete
+          before we close the event it's referencing. */
 
-       device_info = _("Windows tap device");
+       DWORD len;
+       if(!GetOverlappedResult(device_handle, &device_read_overlapped, &len, TRUE) && GetLastError() != ERROR_OPERATION_ABORTED)
+               logger(DEBUG_ALWAYS, LOG_ERR, "Could not wait for %s %s read to cancel: %s", device_info, device, winerror(GetLastError()));
+       if(device_write_packet.len > 0 && !GetOverlappedResult(device_handle, &device_write_overlapped, &len, TRUE) && GetLastError() != ERROR_OPERATION_ABORTED)
+               logger(DEBUG_ALWAYS, LOG_ERR, "Could not wait for %s %s write to cancel: %s", device_info, device, winerror(GetLastError()));
+       device_write_packet.len = 0;
 
-       logger(LOG_INFO, _("%s (%s) is a %s"), device, iface, device_info);
+       CloseHandle(device_read_overlapped.hEvent);
+       CloseHandle(device_write_overlapped.hEvent);
 
-       return true;
+       ULONG status = 0;
+       DeviceIoControl(device_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof status, &status, sizeof status, &len, NULL);
 }
 
-void close_device(void)
-{
-       cp();
+static void close_device(void) {
+       CloseHandle(device_handle); device_handle = INVALID_HANDLE_VALUE;
 
-       CloseHandle(device_handle);
+       free(device); device = NULL;
+       free(iface); iface = NULL;
+       device_info = NULL;
 }
 
-bool read_packet(vpn_packet_t *packet)
-{
-       unsigned char bufno;
-
-       cp();
-
-       if((recv(device_fd, &bufno, 1, 0)) <= 0) {
-               logger(LOG_ERR, _("Error while reading from %s %s: %s"), device_info,
-                          device, strerror(errno));
-               return false;
-       }
-       
-       packet->len = bufs[bufno].len;
-       memcpy(packet->data, bufs[bufno].data, bufs[bufno].len);
+static bool read_packet(vpn_packet_t *packet) {
+       return false;
+}
 
-       device_total_in += packet->len;
+static bool write_packet(vpn_packet_t *packet) {
+       DWORD outlen;
 
-       ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Read packet of %d bytes from %s"), packet->len,
-                          device_info);
+       logger(DEBUG_TRAFFIC, LOG_DEBUG, "Writing packet of %d bytes to %s",
+                          packet->len, device_info);
 
-       return true;
-}
+       if(device_write_packet.len > 0) {
+               /* Make sure the previous write operation is finished before we start the next one;
+                  otherwise we end up with multiple write ops referencing the same OVERLAPPED structure,
+                  which according to MSDN is a no-no. */
 
-bool write_packet(vpn_packet_t *packet)
-{
-       long lenout;
-       OVERLAPPED overlapped = {0};
+               if(!GetOverlappedResult(device_handle, &device_write_overlapped, &outlen, FALSE)) {
+                       int log_level = (GetLastError() == ERROR_IO_INCOMPLETE) ? DEBUG_TRAFFIC : DEBUG_ALWAYS;
+                       logger(log_level, LOG_ERR, "Error while checking previous write to %s %s: %s", device_info, device, winerror(GetLastError()));
+                       return false;
+               }
+       }
 
-       cp();
+       /* Copy the packet, since the write operation might still be ongoing after we return. */
 
-       ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Writing packet of %d bytes to %s"),
-                          packet->len, device_info);
+       memcpy(&device_write_packet, packet, sizeof *packet);
 
-       if(!WriteFile(device_handle, packet->data, packet->len, &lenout, &overlapped)) {
-               logger(LOG_ERR, _("Error while writing to %s %s: %s"), device_info, device, winerror(GetLastError()));
+       if(WriteFile(device_handle, DATA(&device_write_packet), device_write_packet.len, &outlen, &device_write_overlapped))
+               device_write_packet.len = 0;
+       else if (GetLastError() != ERROR_IO_PENDING) {
+               logger(DEBUG_ALWAYS, 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);
-}
+const devops_t os_devops = {
+       .setup = setup_device,
+       .close = close_device,
+       .read = read_packet,
+       .write = write_packet,
+       .enable = enable_device,
+       .disable = disable_device,
+};