mirror
/
devilutionX-ZeroTierOne
mirror of https://github.com/diasurgical/ZeroTierOne.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

Windows tap: be REAL REAL REAL PARANOID. Wake up sheeple.

pull/1/head
Adam Ierymenko 12 years ago
parent
76d9ea911d
commit
bf24de43fe
2 changed files with 85 additions and 68 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 149
      node/WindowsEthernetTap.cpp
  2. 4
      node/WindowsEthernetTap.hpp

149
node/WindowsEthernetTap.cpp
Unescape View File

@ -208,7 +208,7 @@ WindowsEthernetTap::WindowsEthernetTap(
_injectSemaphore(INVALID_HANDLE_VALUE),
_run(true),
_initialized(false),
_enabled(false)
_enabled(true)
{
char subkeyName[4096];
char subkeyClass[4096];
@ -380,37 +380,6 @@ WindowsEthernetTap::WindowsEthernetTap(
throw std::runtime_error("unable to convert instance ID GUID to native GUID (invalid NetCfgInstanceId in registry?)");
}
// Disable and enable interface to ensure registry settings take effect
_disableTapDevice(_r,_deviceInstanceId);
if (!_enableTapDevice(_r,_deviceInstanceId))
throw std::runtime_error("cannot enable tap device driver");
// Open the tap, which is in this weird Windows analog of /dev
char tapPath[4096];
Utils::snprintf(tapPath,sizeof(tapPath),"\\\\.\\Global\\%s.tap",_netCfgInstanceId.c_str());
for(int openTrials=0;;) {
// Try multiple times, since there seem to be reports from the field
// of driver init timing issues. Blech.
_tap = CreateFileA(tapPath,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_SYSTEM|FILE_FLAG_OVERLAPPED,NULL);
if (_tap == INVALID_HANDLE_VALUE) {
if (++openTrials >= 3)
throw std::runtime_error(std::string("unable to open tap device ")+tapPath);
else Sleep(500);
} else break;
}
setEnabled(true);
if (!_enabled) {
CloseHandle(_tap);
throw std::runtime_error("cannot enable tap device using IOCTL");
}
// Initialized overlapped I/O structures and related events
memset(&_tapOvlRead,0,sizeof(_tapOvlRead));
_tapOvlRead.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
memset(&_tapOvlWrite,0,sizeof(_tapOvlWrite));
_tapOvlWrite.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
// Start background thread that actually performs I/O
_injectSemaphore = CreateSemaphore(NULL,0,1,NULL);
_thread = Thread::start(this);
@ -422,29 +391,15 @@ WindowsEthernetTap::WindowsEthernetTap(
WindowsEthernetTap::~WindowsEthernetTap()
{
_run = false;
ReleaseSemaphore(_injectSemaphore,1,NULL);
Thread::join(_thread);
CloseHandle(_tap);
CloseHandle(_tapOvlRead.hEvent);
CloseHandle(_tapOvlWrite.hEvent);
CloseHandle(_injectSemaphore);
_disableTapDevice(_r,_deviceInstanceId);
}
void WindowsEthernetTap::setEnabled(bool en)
{
if (_tap == INVALID_HANDLE_VALUE) {
_enabled = false;
} else {
uint32_t tmpi = (en ? 1 : 0);
DWORD bytesReturned = 0;
if (DeviceIoControl(_tap,TAP_WIN_IOCTL_SET_MEDIA_STATUS,&tmpi,sizeof(tmpi),&tmpi,sizeof(tmpi),&bytesReturned,NULL))
_enabled = en;
else _enabled = false;
}
_enabled = en;
}
bool WindowsEthernetTap::enabled() const
@ -624,6 +579,9 @@ bool WindowsEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
{
if (!_initialized)
return false;
HANDLE t = _tap;
if (t == INVALID_HANDLE_VALUE)
return false;
std::set<MulticastGroup> newGroups;
@ -640,7 +598,7 @@ bool WindowsEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
// pretty much anything work... IPv4, IPv6, IPX, oldskool Netbios, who knows...
unsigned char mcastbuf[TAP_WIN_IOCTL_GET_MULTICAST_MEMBERSHIPS_OUTPUT_BUF_SIZE];
DWORD bytesReturned = 0;
if (DeviceIoControl(_tap,TAP_WIN_IOCTL_GET_MULTICAST_MEMBERSHIPS,(LPVOID)0,0,(LPVOID)mcastbuf,sizeof(mcastbuf),&bytesReturned,NULL)) {
if (DeviceIoControl(t,TAP_WIN_IOCTL_GET_MULTICAST_MEMBERSHIPS,(LPVOID)0,0,(LPVOID)mcastbuf,sizeof(mcastbuf),&bytesReturned,NULL)) {
MAC mac;
DWORD i = 0;
while ((i + 6) <= bytesReturned) {
@ -680,41 +638,95 @@ bool WindowsEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
void WindowsEthernetTap::threadMain()
throw()
{
char tapPath[256];
OVERLAPPED tapOvlRead,tapOvlWrite;
HANDLE wait4[3];
char *tapReadBuf = (char *)0;
// Shouldn't be needed, but Windows does not overcommit. This Windows
// tap code is defensive to schizoid paranoia degrees.
while (!tapReadBuf) {
tapReadBuf = (char *)::malloc(ZT_IF_MTU + 32);
if (!tapReadBuf)
Sleep(1000);
}
// Tap is in this weird Windows global pseudo file space
Utils::snprintf(tapPath,sizeof(tapPath),"\\\\.\\Global\\%s.tap",_netCfgInstanceId.c_str());
// More insanity: repetatively try to enable/disable tap device. The first
// time we succeed, close it and do it again. This is to fix a driver init
// bug that seems to be extremely non-deterministic and to only occur after
// headless MSI upgrade. It cannot be reproduced in any other circumstance.
bool throwOneAway = true;
while (_run) {
_disableTapDevice(_r,_deviceInstanceId);
Sleep(250);
if (!_enableTapDevice(_r,_deviceInstanceId)) {
::free(tapReadBuf);
_enabled = false;
return; // only happens if devcon is missing or totally fails
}
Sleep(250);
_tap = CreateFileA(tapPath,GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_SYSTEM|FILE_FLAG_OVERLAPPED,NULL);
if (_tap == INVALID_HANDLE_VALUE) {
Sleep(500);
continue;
}
uint32_t tmpi = 1;
DWORD bytesReturned = 0;
DeviceIoControl(_tap,TAP_WIN_IOCTL_SET_MEDIA_STATUS,&tmpi,sizeof(tmpi),&tmpi,sizeof(tmpi),&bytesReturned,NULL);
if (throwOneAway) {
throwOneAway = false;
CloseHandle(_tap);
_tap = INVALID_HANDLE_VALUE;
Sleep(250);
continue;
} else break;
}
memset(&tapOvlRead,0,sizeof(tapOvlRead));
tapOvlRead.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
memset(&tapOvlWrite,0,sizeof(tapOvlWrite));
tapOvlWrite.hEvent = CreateEvent(NULL,TRUE,FALSE,NULL);
wait4[0] = _injectSemaphore;
wait4[1] = _tapOvlRead.hEvent;
wait4[2] = _tapOvlWrite.hEvent; // only included if writeInProgress is true
wait4[1] = tapOvlRead.hEvent;
wait4[2] = tapOvlWrite.hEvent; // only included if writeInProgress is true
ReadFile(_tap,_tapReadBuf,sizeof(_tapReadBuf),NULL,&_tapOvlRead);
// Start overlapped read, which is always active
ReadFile(_tap,tapReadBuf,sizeof(tapReadBuf),NULL,&tapOvlRead);
bool writeInProgress = false;
for(;;) {
// Windows can DIAF
if (_enabled)
setEnabled(true);
if (!_run) break;
DWORD r = WaitForMultipleObjectsEx(writeInProgress ? 3 : 2,wait4,FALSE,INFINITE,TRUE);
DWORD r = WaitForMultipleObjectsEx(writeInProgress ? 3 : 2,wait4,FALSE,5000,TRUE);
if (!_run) break;
if (HasOverlappedIoCompleted(&_tapOvlRead)) {
if ((r == WAIT_TIMEOUT)||(r == WAIT_FAILED))
continue;
if (HasOverlappedIoCompleted(&tapOvlRead)) {
DWORD bytesRead = 0;
if (GetOverlappedResult(_tap,&_tapOvlRead,&bytesRead,FALSE)) {
if (GetOverlappedResult(_tap,&tapOvlRead,&bytesRead,FALSE)) {
if ((bytesRead > 14)&&(_enabled)) {
MAC to(_tapReadBuf);
MAC from(_tapReadBuf + 6);
unsigned int etherType = ((((unsigned int)_tapReadBuf[12]) & 0xff) << 8) | (((unsigned int)_tapReadBuf[13]) & 0xff);
MAC to(tapReadBuf);
MAC from(tapReadBuf + 6);
unsigned int etherType = ((((unsigned int)tapReadBuf[12]) & 0xff) << 8) | (((unsigned int)tapReadBuf[13]) & 0xff);
try {
Buffer<4096> tmp(_tapReadBuf + 14,bytesRead - 14);
Buffer<4096> tmp(tapReadBuf + 14,bytesRead - 14);
_handler(_arg,from,to,etherType,tmp);
} catch ( ... ) {} // handlers should not throw
}
}
ReadFile(_tap,_tapReadBuf,sizeof(_tapReadBuf),NULL,&_tapOvlRead);
ReadFile(_tap,tapReadBuf,ZT_IF_MTU + 32,NULL,&tapOvlRead);
}
if (writeInProgress) {
if (HasOverlappedIoCompleted(&_tapOvlWrite)) {
if (HasOverlappedIoCompleted(&tapOvlWrite)) {
writeInProgress = false;
_injectPending_m.lock();
_injectPending.pop();
@ -722,7 +734,7 @@ void WindowsEthernetTap::threadMain()
} else _injectPending_m.lock();
if (!_injectPending.empty()) {
WriteFile(_tap,_injectPending.front().first.data,_injectPending.front().second,NULL,&_tapOvlWrite);
WriteFile(_tap,_injectPending.front().first.data,_injectPending.front().second,NULL,&tapOvlWrite);
writeInProgress = true;
}
@ -730,6 +742,13 @@ void WindowsEthernetTap::threadMain()
}
CancelIo(_tap);
CloseHandle(tapOvlRead.hEvent);
CloseHandle(tapOvlWrite.hEvent);
CloseHandle(_tap);
_tap = INVALID_HANDLE_VALUE;
::free(tapReadBuf);
}
bool WindowsEthernetTap::deletePersistentTapDevice(const RuntimeEnvironment *_r,const char *pid)

4
node/WindowsEthernetTap.hpp
Unescape View File

@ -118,9 +118,7 @@ private:
void *_arg;
Thread _thread;
HANDLE _tap;
OVERLAPPED _tapOvlRead,_tapOvlWrite;
char _tapReadBuf[ZT_IF_MTU + 32];
volatile HANDLE _tap;
HANDLE _injectSemaphore;
GUID _deviceGuid;
std::string _netCfgInstanceId; // NetCfgInstanceId, a GUID

Write Preview
Loading…
Cancel
Save