wintun: take mutex so that deletion uses the right name

This commit is contained in:
Jason A. Donenfeld 2019-08-29 17:42:28 -06:00 committed by Simon Rozman
parent 353f0956bc
commit 14df9c3e75
4 changed files with 84 additions and 25 deletions

7
go.mod
View file

@ -3,7 +3,8 @@ module golang.zx2c4.com/wireguard
go 1.12
require (
golang.org/x/crypto v0.0.0-20190617133340-57b3e21c3d56
golang.org/x/net v0.0.0-20190613194153-d28f0bde5980
golang.org/x/sys v0.0.0-20190618155005-516e3c20635f
golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472
golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297
golang.org/x/sys v0.0.0-20190830023255-19e00faab6ad
golang.org/x/text v0.3.2
)

15
go.sum
View file

@ -1,11 +1,14 @@
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/crypto v0.0.0-20190617133340-57b3e21c3d56 h1:ZpKuNIejY8P0ExLOVyKhb0WsgG8UdvHXe6TWjY7eL6k=
golang.org/x/crypto v0.0.0-20190617133340-57b3e21c3d56/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472 h1:Gv7RPwsi3eZ2Fgewe3CBsuOebPwO27PoXzRpJPsvSSM=
golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20190613194153-d28f0bde5980 h1:dfGZHvZk057jK2MCeWus/TowKpJ8y4AmooUzdBSR9GU=
golang.org/x/net v0.0.0-20190613194153-d28f0bde5980/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297 h1:k7pJ2yAPLPgbskkFdhRCsA77k2fySZ1zf2zCjvQCiIM=
golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20190618155005-516e3c20635f h1:dHNZYIYdq2QuU6w73vZ/DzesPbVlZVYZTtTZmrnsbQ8=
golang.org/x/sys v0.0.0-20190618155005-516e3c20635f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20190830023255-19e00faab6ad h1:cCejgArrk10gX6kFqjWeLwXD7aVMqWoRpyUCaaJSggc=
golang.org/x/sys v0.0.0-20190830023255-19e00faab6ad/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

View file

@ -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,

View file

@ -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
}