ZeroTierOne/osnet/WindowsEthernetTap.cpp

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/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2011-2014 ZeroTier Networks LLC
*
* 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
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* 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, see <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <WinSock2.h>
#include <Windows.h>
#include <tchar.h>
#include <winreg.h>
#include <wchar.h>
#include <ws2ipdef.h>
#include <WS2tcpip.h>
#include <IPHlpApi.h>
#include <nldef.h>
#include <netioapi.h>
#include <atlbase.h>
#include <netlistmgr.h>
#include <nldef.h>
#include <iostream>
#include "../node/Constants.hpp"
#include "WindowsEthernetTap.hpp"
#include "WindowsEthernetTapFactory.hpp"
#include "../node/Utils.hpp"
#include "../node/Mutex.hpp"
#include "..\windows\TapDriver\tap-windows.h"
// ff:ff:ff:ff:ff:ff with no ADI
static const ZeroTier::MulticastGroup _blindWildcardMulticastGroup(ZeroTier::MAC(0xff),0);
#define ZT_WINDOWS_CREATE_FAKE_DEFAULT_ROUTE
namespace ZeroTier {
// Only create or delete devices one at a time
static Mutex _systemTapInitLock;
WindowsEthernetTap::WindowsEthernetTap(
const char *pathToHelpers,
const MAC &mac,
unsigned int mtu,
unsigned int metric,
uint64_t nwid,
const char *desiredDevice,
const char *friendlyName,
void (*handler)(void *,const MAC &,const MAC &,unsigned int,const Buffer<4096> &),
void *arg) :
EthernetTap("WindowsEthernetTap",mac,mtu,metric),
_handler(handler),
_arg(arg),
_nwid(nwid),
_tap(INVALID_HANDLE_VALUE),
_injectSemaphore(INVALID_HANDLE_VALUE),
_pathToHelpers(pathToHelpers),
_run(true),
_initialized(false),
_enabled(true)
{
char subkeyName[4096];
char subkeyClass[4096];
char data[4096];
char tag[24];
if (mtu > 2800)
throw std::runtime_error("MTU too large for Windows tap");
Mutex::Lock _l(_systemTapInitLock);
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HKEY nwAdapters;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}",0,KEY_READ|KEY_WRITE,&nwAdapters) != ERROR_SUCCESS)
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throw std::runtime_error("unable to open registry key for network adapter enumeration");
std::set<std::string> existingDeviceInstances;
std::string mySubkeyName;
// We "tag" registry entries with the network ID to identify persistent devices
Utils::snprintf(tag,sizeof(tag),"%.16llx",(unsigned long long)nwid);
// Look for the tap instance that corresponds with this network
for(DWORD subkeyIndex=0;;++subkeyIndex) {
DWORD type;
DWORD dataLen;
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DWORD subkeyNameLen = sizeof(subkeyName);
DWORD subkeyClassLen = sizeof(subkeyClass);
FILETIME lastWriteTime;
if (RegEnumKeyExA(nwAdapters,subkeyIndex,subkeyName,&subkeyNameLen,(DWORD *)0,subkeyClass,&subkeyClassLen,&lastWriteTime) == ERROR_SUCCESS) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"ComponentId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strnicmp(data,"zttap",5)) {
std::string instanceId;
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"NetCfgInstanceId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
instanceId.assign(data,dataLen);
existingDeviceInstances.insert(instanceId);
}
std::string instanceIdPath;
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"DeviceInstanceID",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS)
instanceIdPath.assign(data,dataLen);
if ((_netCfgInstanceId.length() == 0)&&(instanceId.length() != 0)&&(instanceIdPath.length() != 0)) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"_ZeroTierTapIdentifier",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strcmp(data,tag)) {
_netCfgInstanceId = instanceId;
_deviceInstanceId = instanceIdPath;
mySubkeyName = subkeyName;
break; // found it!
}
}
}
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}
}
} else break; // no more subkeys or error occurred enumerating them
}
// If there is no device, try to create one
bool creatingNewDevice = (_netCfgInstanceId.length() == 0);
if (creatingNewDevice) {
// Log devcon output to a file
HANDLE devconLog = CreateFileA((_pathToHelpers + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
if (devconLog != INVALID_HANDLE_VALUE)
SetFilePointer(devconLog,0,0,FILE_END);
// Execute devcon to install an instance of the Microsoft Loopback Adapter
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
SetFilePointer(devconLog,0,0,FILE_END);
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (!CreateProcessA(NULL,(LPSTR)(std::string("\"") + _pathToHelpers + WindowsEthernetTapFactory::WINENV.devcon + "\" install \"" + _pathToHelpers + WindowsEthernetTapFactory::WINENV.tapDriver + "\" zttap200").c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
RegCloseKey(nwAdapters);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
throw std::runtime_error(std::string("unable to find or execute devcon at ") + WindowsEthernetTapFactory::WINENV.devcon);
}
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
// Scan for the new instance by simply looking for taps that weren't originally there...
for(DWORD subkeyIndex=0;;++subkeyIndex) {
DWORD type;
DWORD dataLen;
DWORD subkeyNameLen = sizeof(subkeyName);
DWORD subkeyClassLen = sizeof(subkeyClass);
FILETIME lastWriteTime;
if (RegEnumKeyExA(nwAdapters,subkeyIndex,subkeyName,&subkeyNameLen,(DWORD *)0,subkeyClass,&subkeyClassLen,&lastWriteTime) == ERROR_SUCCESS) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"ComponentId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
data[dataLen] = '\0';
if (!strnicmp(data,"zttap",5)) {
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"NetCfgInstanceId",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS) {
if (existingDeviceInstances.count(std::string(data,dataLen)) == 0) {
RegSetKeyValueA(nwAdapters,subkeyName,"_ZeroTierTapIdentifier",REG_SZ,tag,(DWORD)(strlen(tag)+1));
_netCfgInstanceId.assign(data,dataLen);
type = 0;
dataLen = sizeof(data);
if (RegGetValueA(nwAdapters,subkeyName,"DeviceInstanceID",RRF_RT_ANY,&type,(PVOID)data,&dataLen) == ERROR_SUCCESS)
_deviceInstanceId.assign(data,dataLen);
mySubkeyName = subkeyName;
// Disable DHCP by default on newly created devices
HKEY tcpIpInterfaces;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\services\\Tcpip\\Parameters\\Interfaces",0,KEY_READ|KEY_WRITE,&tcpIpInterfaces) == ERROR_SUCCESS) {
DWORD enable = 0;
RegSetKeyValueA(tcpIpInterfaces,_netCfgInstanceId.c_str(),"EnableDHCP",REG_DWORD,&enable,sizeof(enable));
RegCloseKey(tcpIpInterfaces);
}
break; // found it!
}
}
}
}
} else break; // no more keys or error occurred
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}
}
if (_netCfgInstanceId.length() > 0) {
char tmps[64];
unsigned int tmpsl = Utils::snprintf(tmps,sizeof(tmps),"%.2X-%.2X-%.2X-%.2X-%.2X-%.2X",(unsigned int)mac[0],(unsigned int)mac[1],(unsigned int)mac[2],(unsigned int)mac[3],(unsigned int)mac[4],(unsigned int)mac[5]) + 1;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"NetworkAddress",REG_SZ,tmps,tmpsl);
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"MAC",REG_SZ,tmps,tmpsl);
DWORD tmp = mtu;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"MTU",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
tmp = 0;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"*NdisDeviceType",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
tmp = IF_TYPE_ETHERNET_CSMACD;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"*IfType",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
if (creatingNewDevice) {
tmp = 0;
RegSetKeyValueA(nwAdapters,mySubkeyName.c_str(),"EnableDHCP",REG_DWORD,(LPCVOID)&tmp,sizeof(tmp));
}
RegCloseKey(nwAdapters);
} else {
RegCloseKey(nwAdapters);
throw std::runtime_error("unable to find or create tap adapter");
}
// Convert device GUID junk... blech... is there an easier way to do this?
{
char nobraces[128];
const char *nbtmp1 = _netCfgInstanceId.c_str();
char *nbtmp2 = nobraces;
while (*nbtmp1) {
if ((*nbtmp1 != '{')&&(*nbtmp1 != '}'))
*nbtmp2++ = *nbtmp1;
++nbtmp1;
}
*nbtmp2 = (char)0;
if (UuidFromStringA((RPC_CSTR)nobraces,&_deviceGuid) != RPC_S_OK)
throw std::runtime_error("unable to convert instance ID GUID to native GUID (invalid NetCfgInstanceId in registry?)");
}
// Look up interface LUID... why are there (at least) four fucking ways to refer to a network device in Windows?
if (ConvertInterfaceGuidToLuid(&_deviceGuid,&_deviceLuid) != NO_ERROR)
throw std::runtime_error("unable to convert device interface GUID to LUID");
if (friendlyName)
setFriendlyName(friendlyName);
// Start background thread that actually performs I/O
_injectSemaphore = CreateSemaphore(NULL,0,1,NULL);
_thread = Thread::start(this);
// Certain functions can now work (e.g. ips())
_initialized = true;
}
WindowsEthernetTap::~WindowsEthernetTap()
{
_run = false;
ReleaseSemaphore(_injectSemaphore,1,NULL);
Thread::join(_thread);
CloseHandle(_injectSemaphore);
_disableTapDevice();
}
void WindowsEthernetTap::setEnabled(bool en)
{
_enabled = en;
}
bool WindowsEthernetTap::enabled() const
{
return _enabled;
}
bool WindowsEthernetTap::addIP(const InetAddress &ip)
{
if (!_initialized)
return false;
if (!ip.netmaskBits()) // sanity check... netmask of 0.0.0.0 is WUT?
return false;
std::set<InetAddress> haveIps(ips());
try {
// Add IP to interface at the netlink level if not already assigned.
if (!haveIps.count(ip)) {
MIB_UNICASTIPADDRESS_ROW ipr;
InitializeUnicastIpAddressEntry(&ipr);
if (ip.isV4()) {
ipr.Address.Ipv4.sin_family = AF_INET;
ipr.Address.Ipv4.sin_addr.S_un.S_addr = *((const uint32_t *)ip.rawIpData());
ipr.OnLinkPrefixLength = ip.port();
if (ipr.OnLinkPrefixLength >= 32)
return false;
} else if (ip.isV6()) {
ipr.Address.Ipv6.sin6_family = AF_INET6;
memcpy(ipr.Address.Ipv6.sin6_addr.u.Byte,ip.rawIpData(),16);
ipr.OnLinkPrefixLength = ip.port();
if (ipr.OnLinkPrefixLength >= 128)
return false;
} else return false;
ipr.PrefixOrigin = IpPrefixOriginManual;
ipr.SuffixOrigin = IpSuffixOriginManual;
ipr.ValidLifetime = 0xffffffff;
ipr.PreferredLifetime = 0xffffffff;
ipr.InterfaceLuid = _deviceLuid;
ipr.InterfaceIndex = _getDeviceIndex();
if (CreateUnicastIpAddressEntry(&ipr) == NO_ERROR) {
haveIps.insert(ip);
} else {
return false;
}
}
std::vector<std::string> regIps(_getRegistryIPv4Value("IPAddress"));
if (std::find(regIps.begin(),regIps.end(),ip.toIpString()) == regIps.end()) {
std::vector<std::string> regSubnetMasks(_getRegistryIPv4Value("SubnetMask"));
regIps.push_back(ip.toIpString());
regSubnetMasks.push_back(ip.netmask().toIpString());
_setRegistryIPv4Value("IPAddress",regIps);
_setRegistryIPv4Value("SubnetMask",regSubnetMasks);
}
//_syncIpsWithRegistry(haveIps,_netCfgInstanceId);
} catch ( ... ) {
return false;
}
return true;
}
bool WindowsEthernetTap::removeIP(const InetAddress &ip)
{
if (!_initialized)
return false;
try {
MIB_UNICASTIPADDRESS_TABLE *ipt = (MIB_UNICASTIPADDRESS_TABLE *)0;
if (GetUnicastIpAddressTable(AF_UNSPEC,&ipt) == NO_ERROR) {
for(DWORD i=0;i<ipt->NumEntries;++i) {
if (ipt->Table[i].InterfaceLuid.Value == _deviceLuid.Value) {
InetAddress addr;
switch(ipt->Table[i].Address.si_family) {
case AF_INET:
addr.set(&(ipt->Table[i].Address.Ipv4.sin_addr.S_un.S_addr),4,ipt->Table[i].OnLinkPrefixLength);
break;
case AF_INET6:
addr.set(ipt->Table[i].Address.Ipv6.sin6_addr.u.Byte,16,ipt->Table[i].OnLinkPrefixLength);
if (addr.isLinkLocal())
continue; // can't remove link-local IPv6 addresses
break;
}
if (addr == ip) {
DeleteUnicastIpAddressEntry(&(ipt->Table[i]));
FreeMibTable(ipt);
std::vector<std::string> regIps(_getRegistryIPv4Value("IPAddress"));
std::vector<std::string> regSubnetMasks(_getRegistryIPv4Value("SubnetMask"));
std::string ipstr(ip.toIpString());
for(std::vector<std::string>::iterator rip(regIps.begin()),rm(regSubnetMasks.begin());((rip!=regIps.end())&&(rm!=regSubnetMasks.end()));++rip,++rm) {
if (*rip == ipstr) {
regIps.erase(rip);
regSubnetMasks.erase(rm);
_setRegistryIPv4Value("IPAddress",regIps);
_setRegistryIPv4Value("SubnetMask",regSubnetMasks);
break;
}
}
return true;
}
}
}
FreeMibTable((PVOID)ipt);
}
} catch ( ... ) {}
return false;
}
std::set<InetAddress> WindowsEthernetTap::ips() const
{
static const InetAddress linkLocalLoopback("fe80::1",64); // what is this and why does Windows assign it?
std::set<InetAddress> addrs;
if (!_initialized)
return addrs;
try {
MIB_UNICASTIPADDRESS_TABLE *ipt = (MIB_UNICASTIPADDRESS_TABLE *)0;
if (GetUnicastIpAddressTable(AF_UNSPEC,&ipt) == NO_ERROR) {
for(DWORD i=0;i<ipt->NumEntries;++i) {
if (ipt->Table[i].InterfaceLuid.Value == _deviceLuid.Value) {
switch(ipt->Table[i].Address.si_family) {
case AF_INET: {
InetAddress ip(&(ipt->Table[i].Address.Ipv4.sin_addr.S_un.S_addr),4,ipt->Table[i].OnLinkPrefixLength);
if (ip != InetAddress::LO4)
addrs.insert(ip);
} break;
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case AF_INET6: {
InetAddress ip(ipt->Table[i].Address.Ipv6.sin6_addr.u.Byte,16,ipt->Table[i].OnLinkPrefixLength);
if ((ip != linkLocalLoopback)&&(ip != InetAddress::LO6))
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addrs.insert(ip);
} break;
}
}
}
FreeMibTable(ipt);
}
} catch ( ... ) {} // sanity check, shouldn't happen unless out of memory
return addrs;
}
void WindowsEthernetTap::put(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len)
{
if ((!_initialized)||(!_enabled)||(_tap == INVALID_HANDLE_VALUE)||(len > (ZT_IF_MTU)))
return;
Mutex::Lock _l(_injectPending_m);
_injectPending.push( std::pair<Array<char,ZT_IF_MTU + 32>,unsigned int>(Array<char,ZT_IF_MTU + 32>(),len + 14) );
char *d = _injectPending.back().first.data;
to.copyTo(d,6);
from.copyTo(d + 6,6);
d[12] = (char)((etherType >> 8) & 0xff);
d[13] = (char)(etherType & 0xff);
memcpy(d + 14,data,len);
ReleaseSemaphore(_injectSemaphore,1,NULL);
}
std::string WindowsEthernetTap::deviceName() const
{
char tmp[1024];
if (ConvertInterfaceLuidToNameA(&_deviceLuid,tmp,sizeof(tmp)) != NO_ERROR)
return std::string("[ConvertInterfaceLuidToName() failed]");
return std::string(tmp);
}
void WindowsEthernetTap::setFriendlyName(const char *dn)
{
if (!_initialized)
return;
HKEY ifp;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,(std::string("SYSTEM\\CurrentControlSet\\Control\\Network\\{4D36E972-E325-11CE-BFC1-08002BE10318}\\") + _netCfgInstanceId).c_str(),0,KEY_READ|KEY_WRITE,&ifp) == ERROR_SUCCESS) {
RegSetKeyValueA(ifp,"Connection","Name",REG_SZ,(LPCVOID)dn,(DWORD)(strlen(dn)+1));
RegCloseKey(ifp);
}
}
bool WindowsEthernetTap::updateMulticastGroups(std::set<MulticastGroup> &groups)
{
if (!_initialized)
return false;
HANDLE t = _tap;
if (t == INVALID_HANDLE_VALUE)
return false;
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std::set<MulticastGroup> newGroups;
// Ensure that groups are added for each IP... this handles the MAC:ADI
// groups that are created from IPv4 addresses. Some of these may end
// up being duplicates of what the IOCTL returns but that's okay since
// the set<> will filter that.
std::set<InetAddress> ipaddrs(ips());
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for(std::set<InetAddress>::const_iterator i(ipaddrs.begin());i!=ipaddrs.end();++i)
newGroups.insert(MulticastGroup::deriveMulticastGroupForAddressResolution(*i));
// The ZT1 tap driver supports an IOCTL to get multicast memberships at the L2
// level... something Windows does not seem to expose ordinarily. This lets
// 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(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) {
mac.setTo(mcastbuf + i,6);
i += 6;
if ((mac.isMulticast())&&(!mac.isBroadcast())) {
// exclude the nulls that may be returned or any other junk Windows puts in there
newGroups.insert(MulticastGroup(mac,0));
}
}
}
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bool changed = false;
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for(std::set<MulticastGroup>::iterator mg(newGroups.begin());mg!=newGroups.end();++mg) {
if (!groups.count(*mg)) {
groups.insert(*mg);
changed = true;
}
}
for(std::set<MulticastGroup>::iterator mg(groups.begin());mg!=groups.end();) {
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if ((!newGroups.count(*mg))&&(*mg != _blindWildcardMulticastGroup)) {
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groups.erase(mg++);
changed = true;
} else ++mg;
}
return changed;
}
bool WindowsEthernetTap::injectPacketFromHost(const MAC &from,const MAC &to,unsigned int etherType,const void *data,unsigned int len)
{
return false;
}
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.
*
* Eventually when ZeroTier has actual money we will have someone create an
* NDIS6 tap driver. Yes, we'll likely be cool and open source it. */
bool throwOneAway = true;
while (_run) {
_disableTapDevice();
Sleep(250);
if (!_enableTapDevice()) {
::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);
bytesReturned = 0;
DeviceIoControl(_tap,TAP_WIN_IOCTL_SET_MEDIA_STATUS,&tmpi,sizeof(tmpi),&tmpi,sizeof(tmpi),&bytesReturned,NULL);
}
{
#ifdef ZT_WINDOWS_CREATE_FAKE_DEFAULT_ROUTE
/* This inserts a fake default route and a fake ARP entry, forcing
* Windows to detect this as a "real" network and apply proper
* firewall rules.
*
* This hack is completely stupid, but Windows made me do it
* by being broken and insane.
*
* Background: Windows tries to detect its network location by
* matching it to the ARP address of the default route. Networks
* without default routes are "unidentified networks" and cannot
* have their firewall classification changed by the user (easily).
*
* Yes, you read that right.
*
* The common workaround is to set *NdisDeviceType to 1, which
* totally disables all Windows firewall functionality. This is
* the answer you'll find on most forums for things like OpenVPN.
*
* Yes, you read that right.
*
* The default route workaround is also known, but for this to
* work there must be a known default IP that resolves to a known
* ARP address. This works for an OpenVPN tunnel, but not here
* because this isn't a tunnel. It's a mesh. There is no "other
* end," or any other known always on IP.
*
* So let's make a fake one and shove it in there along with its
* fake static ARP entry. Also makes it instant-on and static.
*
* We'll have to see what DHCP does with this. In the future we
* probably will not want to do this on DHCP-enabled networks, so
* when we enable DHCP we will go in and yank this wacko hacko from
* the routing table before doing so.
*
* Like Jesse Pinkman would say: "YEEEEAAH BITCH!" */
const uint32_t fakeIp = htonl(0x19fffffe); // 25.255.255.254 -- unrouted IPv4 block
for(int i=0;i<8;++i) {
MIB_IPNET_ROW2 ipnr;
memset(&ipnr,0,sizeof(ipnr));
ipnr.Address.si_family = AF_INET;
ipnr.Address.Ipv4.sin_addr.s_addr = fakeIp;
ipnr.InterfaceLuid.Value = _deviceLuid.Value;
ipnr.PhysicalAddress[0] = _mac[0] ^ 0x10; // just make something up that's consistent and not part of this net
ipnr.PhysicalAddress[1] = 0x00;
ipnr.PhysicalAddress[2] = (UCHAR)((_deviceGuid.Data1 >> 24) & 0xff);
ipnr.PhysicalAddress[3] = (UCHAR)((_deviceGuid.Data1 >> 16) & 0xff);
ipnr.PhysicalAddress[4] = (UCHAR)((_deviceGuid.Data1 >> 8) & 0xff);
ipnr.PhysicalAddress[5] = (UCHAR)(_deviceGuid.Data1 & 0xff);
ipnr.PhysicalAddressLength = 6;
ipnr.State = NlnsPermanent;
ipnr.IsRouter = 1;
ipnr.IsUnreachable = 0;
ipnr.ReachabilityTime.LastReachable = 0x0fffffff;
ipnr.ReachabilityTime.LastUnreachable = 1;
DWORD result = CreateIpNetEntry2(&ipnr);
if (result != NO_ERROR)
Sleep(500);
else break;
}
for(int i=0;i<8;++i) {
MIB_IPFORWARD_ROW2 nr;
memset(&nr,0,sizeof(nr));
InitializeIpForwardEntry(&nr);
nr.InterfaceLuid.Value = _deviceLuid.Value;
nr.DestinationPrefix.Prefix.si_family = AF_INET; // rest is left as 0.0.0.0/0
nr.NextHop.si_family = AF_INET;
nr.NextHop.Ipv4.sin_addr.s_addr = fakeIp;
nr.Metric = 9999; // do not use as real default route
nr.Protocol = MIB_IPPROTO_NETMGMT;
DWORD result = CreateIpForwardEntry2(&nr);
if (result != NO_ERROR)
Sleep(500);
else break;
}
#endif
}
if (throwOneAway) {
throwOneAway = false;
CloseHandle(_tap);
_tap = INVALID_HANDLE_VALUE;
Sleep(1000);
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
// Start overlapped read, which is always active
ReadFile(_tap,tapReadBuf,sizeof(tapReadBuf),NULL,&tapOvlRead);
bool writeInProgress = false;
for(;;) {
if (!_run) break;
DWORD r = WaitForMultipleObjectsEx(writeInProgress ? 3 : 2,wait4,FALSE,5000,TRUE);
if (!_run) break;
if ((r == WAIT_TIMEOUT)||(r == WAIT_FAILED))
continue;
if (HasOverlappedIoCompleted(&tapOvlRead)) {
DWORD bytesRead = 0;
if (GetOverlappedResult(_tap,&tapOvlRead,&bytesRead,FALSE)) {
if ((bytesRead > 14)&&(_enabled)) {
MAC to(tapReadBuf,6);
MAC from(tapReadBuf + 6,6);
unsigned int etherType = ((((unsigned int)tapReadBuf[12]) & 0xff) << 8) | (((unsigned int)tapReadBuf[13]) & 0xff);
try {
Buffer<4096> tmp(tapReadBuf + 14,bytesRead - 14);
_handler(_arg,from,to,etherType,tmp);
} catch ( ... ) {} // handlers should not throw
}
}
ReadFile(_tap,tapReadBuf,ZT_IF_MTU + 32,NULL,&tapOvlRead);
}
if (writeInProgress) {
if (HasOverlappedIoCompleted(&tapOvlWrite)) {
writeInProgress = false;
_injectPending_m.lock();
_injectPending.pop();
} else continue; // still writing, so skip code below and wait
} else _injectPending_m.lock();
if (!_injectPending.empty()) {
WriteFile(_tap,_injectPending.front().first.data,_injectPending.front().second,NULL,&tapOvlWrite);
writeInProgress = true;
}
_injectPending_m.unlock();
}
CancelIo(_tap);
CloseHandle(tapOvlRead.hEvent);
CloseHandle(tapOvlWrite.hEvent);
CloseHandle(_tap);
_tap = INVALID_HANDLE_VALUE;
::free(tapReadBuf);
}
bool WindowsEthernetTap::_disableTapDevice()
{
HANDLE devconLog = CreateFileA((_pathToHelpers + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
if (devconLog != INVALID_HANDLE_VALUE)
SetFilePointer(devconLog,0,0,FILE_END);
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (!CreateProcessA(NULL,(LPSTR)(std::string("\"") + _pathToHelpers + WindowsEthernetTapFactory::WINENV.devcon + "\" disable @" + _deviceInstanceId).c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
return false;
}
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
return true;
}
bool WindowsEthernetTap::_enableTapDevice()
{
HANDLE devconLog = CreateFileA((_pathToHelpers + "\\devcon.log").c_str(),GENERIC_WRITE,FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
if (devconLog != INVALID_HANDLE_VALUE)
SetFilePointer(devconLog,0,0,FILE_END);
STARTUPINFOA startupInfo;
startupInfo.cb = sizeof(startupInfo);
if (devconLog != INVALID_HANDLE_VALUE) {
startupInfo.hStdOutput = devconLog;
startupInfo.hStdError = devconLog;
}
PROCESS_INFORMATION processInfo;
memset(&startupInfo,0,sizeof(STARTUPINFOA));
memset(&processInfo,0,sizeof(PROCESS_INFORMATION));
if (!CreateProcessA(NULL,(LPSTR)(std::string("\"") + _pathToHelpers + WindowsEthernetTapFactory::WINENV.devcon + "\" enable @" + _deviceInstanceId).c_str(),NULL,NULL,FALSE,0,NULL,NULL,&startupInfo,&processInfo)) {
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
return false;
}
WaitForSingleObject(processInfo.hProcess,INFINITE);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
if (devconLog != INVALID_HANDLE_VALUE)
CloseHandle(devconLog);
return true;
}
NET_IFINDEX WindowsEthernetTap::_getDeviceIndex()
{
MIB_IF_TABLE2 *ift = (MIB_IF_TABLE2 *)0;
if (GetIfTable2Ex(MibIfTableRaw,&ift) != NO_ERROR)
throw std::runtime_error("GetIfTable2Ex() failed");
for(ULONG i=0;i<ift->NumEntries;++i) {
if (ift->Table[i].InterfaceLuid.Value == _deviceLuid.Value) {
NET_IFINDEX idx = ift->Table[i].InterfaceIndex;
FreeMibTable(ift);
return idx;
}
}
FreeMibTable(&ift);
throw std::runtime_error("interface not found");
}
std::vector<std::string> WindowsEthernetTap::_getRegistryIPv4Value(const char *regKey)
{
std::vector<std::string> value;
HKEY tcpIpInterfaces;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\services\\Tcpip\\Parameters\\Interfaces",0,KEY_READ|KEY_WRITE,&tcpIpInterfaces) == ERROR_SUCCESS) {
char buf[16384];
DWORD len = sizeof(buf);
DWORD kt = REG_MULTI_SZ;
if (RegGetValueA(tcpIpInterfaces,_netCfgInstanceId.c_str(),regKey,0,&kt,&buf,&len) == ERROR_SUCCESS) {
switch(kt) {
case REG_SZ:
if (len > 0)
value.push_back(std::string(buf));
break;
case REG_MULTI_SZ: {
for(DWORD k=0,s=0;k<len;++k) {
if (!buf[k]) {
if (s < k) {
value.push_back(std::string(buf + s));
s = k + 1;
} else break;
}
}
} break;
}
}
RegCloseKey(tcpIpInterfaces);
}
return value;
}
void WindowsEthernetTap::_setRegistryIPv4Value(const char *regKey,const std::vector<std::string> &value)
{
std::string regMulti;
for(std::vector<std::string>::const_iterator s(value.begin());s!=value.end();++s) {
regMulti.append(*s);
regMulti.push_back((char)0);
}
HKEY tcpIpInterfaces;
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE,"SYSTEM\\CurrentControlSet\\services\\Tcpip\\Parameters\\Interfaces",0,KEY_READ|KEY_WRITE,&tcpIpInterfaces) == ERROR_SUCCESS) {
if (regMulti.length() > 0) {
regMulti.push_back((char)0);
RegSetKeyValueA(tcpIpInterfaces,_netCfgInstanceId.c_str(),regKey,REG_MULTI_SZ,regMulti.data(),(DWORD)regMulti.length());
} else {
RegDeleteKeyValueA(tcpIpInterfaces,_netCfgInstanceId.c_str(),regKey);
}
RegCloseKey(tcpIpInterfaces);
}
}
} // namespace ZeroTier