diff options
Diffstat (limited to 'tun')
| -rw-r--r-- | tun/tun_windows.go | 8 | ||||
| -rw-r--r-- | tun/wintun/wintun_windows.go | 79 |
2 files changed, 71 insertions, 16 deletions
diff --git a/tun/tun_windows.go b/tun/tun_windows.go index 9c635b5..43f0cec 100644 --- a/tun/tun_windows.go +++ b/tun/tun_windows.go @@ -75,17 +75,11 @@ func CreateTUNWithRequestedGUID(ifname string, requestedGUID *windows.GUID) (Dev return nil, fmt.Errorf("Unable to delete already existing Wintun interface: %v", err) } } - wt, _, err = WintunPool.CreateInterface(requestedGUID) + wt, _, err = WintunPool.CreateInterface(ifname, requestedGUID) if err != nil { return nil, fmt.Errorf("Unable to create Wintun interface: %v", err) } - err = wt.SetName(ifname) - if err != nil { - wt.DeleteInterface() - return nil, fmt.Errorf("Unable to set name of Wintun interface: %v", err) - } - tun := &NativeTun{ wt: wt, handle: windows.InvalidHandle, diff --git a/tun/wintun/wintun_windows.go b/tun/wintun/wintun_windows.go index e726748..d6fa35f 100644 --- a/tun/wintun/wintun_windows.go +++ b/tun/wintun/wintun_windows.go @@ -6,14 +6,17 @@ package wintun import ( + "encoding/hex" "errors" "fmt" "strings" "time" "unsafe" + "golang.org/x/crypto/blake2s" "golang.org/x/sys/windows" "golang.org/x/sys/windows/registry" + "golang.org/x/text/unicode/norm" "golang.zx2c4.com/wireguard/tun/wintun/iphlpapi" "golang.zx2c4.com/wireguard/tun/wintun/nci" @@ -99,6 +102,15 @@ func removeNumberedSuffix(ifname string) string { // the interface is found but not a Wintun-class or a member of the pool, // this function returns windows.ERROR_ALREADY_EXISTS. func (pool Pool) GetInterface(ifname string) (*Interface, error) { + mutex, err := pool.takeNameMutex() + if err != nil { + return nil, err + } + defer func() { + windows.ReleaseMutex(mutex) + windows.CloseHandle(mutex) + }() + // Create a list of network devices. devInfoList, err := setupapi.SetupDiGetClassDevsEx(&deviceClassNetGUID, "", 0, setupapi.DIGCF_PRESENT, setupapi.DevInfo(0), "") if err != nil { @@ -178,14 +190,15 @@ func (pool Pool) GetInterface(ifname string) (*Interface, error) { return nil, windows.ERROR_OBJECT_NOT_FOUND } -// CreateInterface creates a Wintun interface. requestedGUID is the GUID of the -// created network interface, which then influences NLA generation -// deterministically. If it is set to nil, the GUID is chosen by the system at -// random, and hence a new NLA entry is created for each new interface. It is -// called "requested" GUID because the API it uses is completely undocumented, -// and so there could be minor interesting complications with its usage. This -// function returns the network interface ID and a flag if reboot is required. -func (pool Pool) CreateInterface(requestedGUID *windows.GUID) (wintun *Interface, rebootRequired bool, err error) { +// CreateInterface creates a Wintun interface. ifname is the requested name of +// the interface, while requestedGUID is the GUID of the created network +// interface, which then influences NLA generation deterministically. If it is +// set to nil, the GUID is chosen by the system at random, and hence a new NLA +// entry is created for each new interface. It is called "requested" GUID +// because the API it uses is completely undocumented, and so there could be minor +// interesting complications with its usage. This function returns the network +// interface ID and a flag if reboot is required. +func (pool Pool) CreateInterface(ifname string, requestedGUID *windows.GUID) (wintun *Interface, rebootRequired bool, err error) { // Create an empty device info set for network adapter device class. devInfoList, err := setupapi.SetupDiCreateDeviceInfoListEx(&deviceClassNetGUID, 0, "") if err != nil { @@ -271,6 +284,15 @@ func (pool Pool) CreateInterface(requestedGUID *windows.GUID) (wintun *Interface return } + mutex, err := pool.takeNameMutex() + if err != nil { + return + } + defer func() { + windows.ReleaseMutex(mutex) + windows.CloseHandle(mutex) + }() + defer func() { if err != nil { // The interface failed to install, or the interface ID was unobtainable. Clean-up. @@ -403,6 +425,12 @@ func (pool Pool) CreateInterface(requestedGUID *windows.GUID) (wintun *Interface // Disable dead gateway detection on our interface. tcpipInterfaceRegKey.SetDWordValue("EnableDeadGWDetect", 0) + err = wintun.SetName(ifname) + if err != nil { + err = fmt.Errorf("Unable to set name of Wintun interface: %v", err) + return + } + return } @@ -444,6 +472,16 @@ func (wintun *Interface) DeleteInterface() (rebootRequired bool, err error) { // given criteria, and returns which ones it deleted, whether a reboot // is required after, and which errors occurred during the process. func (pool Pool) DeleteMatchingInterfaces(matches func(wintun *Interface) bool) (deviceInstancesDeleted []uint32, rebootRequired bool, errors []error) { + mutex, err := pool.takeNameMutex() + if err != nil { + errors = append(errors, err) + return + } + defer func() { + windows.ReleaseMutex(mutex) + windows.CloseHandle(mutex) + }() + devInfoList, err := setupapi.SetupDiGetClassDevsEx(&deviceClassNetGUID, "", 0, setupapi.DIGCF_PRESENT, setupapi.DevInfo(0), "") if err != nil { return nil, false, []error{fmt.Errorf("SetupDiGetClassDevsEx(%v) failed: %v", deviceClassNetGUID, err.Error())} @@ -498,7 +536,7 @@ func (pool Pool) DeleteMatchingInterfaces(matches func(wintun *Interface) bool) wintun, err := makeWintun(devInfoList, deviceData, pool) if err != nil { - errors = append(errors, fmt.Errorf("makeWintun failed: %v", err)) + errors = append(errors, fmt.Errorf("Unable to make Wintun interface object: %v", err)) continue } if !matches(wintun) { @@ -720,3 +758,26 @@ func (wintun *Interface) GUID() windows.GUID { func (wintun *Interface) LUID() uint64 { return ((uint64(wintun.luidIndex) & ((1 << 24) - 1)) << 24) | ((uint64(wintun.ifType) & ((1 << 16) - 1)) << 48) } + +func (pool Pool) takeNameMutex() (windows.Handle, error) { + const mutexLabel = "WireGuard Adapter Name Mutex Stable Suffix v1 jason@zx2c4.com" + b2, _ := blake2s.New256(nil) + b2.Write([]byte(mutexLabel)) + b2.Write(norm.NFC.Bytes([]byte(string(pool)))) + mutexName := `Global\Wintun-Name-Mutex-` + hex.EncodeToString(b2.Sum(nil)) + mutex, err := windows.CreateMutex(nil, false, windows.StringToUTF16Ptr(mutexName)) + if err != nil { + err = fmt.Errorf("Error creating name mutex: %v", err) + return 0, err + } + event, err := windows.WaitForSingleObject(mutex, windows.INFINITE) + if err != nil { + windows.CloseHandle(mutex) + return 0, fmt.Errorf("Error waiting on name mutex: %v", err) + } + if event != windows.WAIT_OBJECT_0 { + windows.CloseHandle(mutex) + return 0, errors.New("Error with event trigger of name mutex") + } + return mutex, nil +}
\ No newline at end of file |