wintun: rename duplicate adapters instead of ourselves

diff --git a/tun/wintun/iphlpapi/conversion_windows.go b/tun/wintun/iphlpapi/conversion_windows.go
new file mode 100644 (file)
index 0000000..a19e961
--- /dev/null
+++ b/tun/wintun/iphlpapi/conversion_windows.go
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
+ */
+
+package iphlpapi
+
+import "golang.org/x/sys/windows"
+
+//sys  convertInterfaceLUIDToGUID(interfaceLUID *uint64, interfaceGUID *windows.GUID) (ret error) = iphlpapi.ConvertInterfaceLuidToGuid
+//sys  convertInterfaceAliasToLUID(interfaceAlias *uint16, interfaceLUID *uint64) (ret error) = iphlpapi.ConvertInterfaceAliasToLuid
+
+func InterfaceGUIDFromAlias(alias string) (*windows.GUID, error) {
+       var luid uint64
+       var guid windows.GUID
+       err := convertInterfaceAliasToLUID(windows.StringToUTF16Ptr(alias), &luid)
+       if err != nil {
+               return nil, err
+       }
+       err = convertInterfaceLUIDToGUID(&luid, &guid)
+       if err != nil {
+               return nil, err
+       }
+       return &guid, nil
+}

diff --git a/tun/wintun/iphlpapi/mksyscall.go b/tun/wintun/iphlpapi/mksyscall.go
new file mode 100644 (file)
index 0000000..f2639ea
--- /dev/null
+++ b/tun/wintun/iphlpapi/mksyscall.go
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
+ */
+
+package iphlpapi
+
+//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall_windows.go conversion_windows.go

diff --git a/tun/wintun/iphlpapi/zsyscall_windows.go b/tun/wintun/iphlpapi/zsyscall_windows.go
new file mode 100644 (file)
index 0000000..dc14294
--- /dev/null
+++ b/tun/wintun/iphlpapi/zsyscall_windows.go
@@ -0,0 +1,60 @@
+// Code generated by 'go generate'; DO NOT EDIT.
+
+package iphlpapi
+
+import (
+       "syscall"
+       "unsafe"
+
+       "golang.org/x/sys/windows"
+)
+
+var _ unsafe.Pointer
+
+// Do the interface allocations only once for common
+// Errno values.
+const (
+       errnoERROR_IO_PENDING = 997
+)
+
+var (
+       errERROR_IO_PENDING error = syscall.Errno(errnoERROR_IO_PENDING)
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+       switch e {
+       case 0:
+               return nil
+       case errnoERROR_IO_PENDING:
+               return errERROR_IO_PENDING
+       }
+       // TODO: add more here, after collecting data on the common
+       // error values see on Windows. (perhaps when running
+       // all.bat?)
+       return e
+}
+
+var (
+       modiphlpapi = windows.NewLazySystemDLL("iphlpapi.dll")
+
+       procConvertInterfaceLuidToGuid  = modiphlpapi.NewProc("ConvertInterfaceLuidToGuid")
+       procConvertInterfaceAliasToLuid = modiphlpapi.NewProc("ConvertInterfaceAliasToLuid")
+)
+
+func convertInterfaceLUIDToGUID(interfaceLUID *uint64, interfaceGUID *windows.GUID) (ret error) {
+       r0, _, _ := syscall.Syscall(procConvertInterfaceLuidToGuid.Addr(), 2, uintptr(unsafe.Pointer(interfaceLUID)), uintptr(unsafe.Pointer(interfaceGUID)), 0)
+       if r0 != 0 {
+               ret = syscall.Errno(r0)
+       }
+       return
+}
+
+func convertInterfaceAliasToLUID(interfaceAlias *uint16, interfaceLUID *uint64) (ret error) {
+       r0, _, _ := syscall.Syscall(procConvertInterfaceAliasToLuid.Addr(), 2, uintptr(unsafe.Pointer(interfaceAlias)), uintptr(unsafe.Pointer(interfaceLUID)), 0)
+       if r0 != 0 {
+               ret = syscall.Errno(r0)
+       }
+       return
+}

diff --git a/tun/wintun/wintun_windows.go b/tun/wintun/wintun_windows.go
index 81da2517b0e13df44577b88724fee13d7ec8524a..f5d42eb2b349500384e8120283899bb28ee91f98 100644 (file)
--- a/tun/wintun/wintun_windows.go
+++ b/tun/wintun/wintun_windows.go
@@ -15,6 +15,7 @@ import (
        "golang.org/x/sys/windows"
        "golang.org/x/sys/windows/registry"
 
+       "golang.zx2c4.com/wireguard/tun/wintun/iphlpapi"
        "golang.zx2c4.com/wireguard/tun/wintun/nci"
        registryEx "golang.zx2c4.com/wireguard/tun/wintun/registry"
        "golang.zx2c4.com/wireguard/tun/wintun/setupapi"
@@ -528,11 +529,35 @@ func (wintun *Wintun) InterfaceName() (string, error) {
 func (wintun *Wintun) SetInterfaceName(ifname string) error {
        const maxSuffix = 1000
        availableIfname := ifname
+setloop:
        for i := 0; ; i++ {
                err := nci.SetConnectionName(&wintun.cfgInstanceID, availableIfname)
                if err == nil {
                        break
                }
+               if err == windows.ERROR_DUP_NAME {
+                       duplicateGuid, err2 := iphlpapi.InterfaceGUIDFromAlias(availableIfname)
+                       if err2 == nil {
+                               for j := 0; j < 1000; j++ {
+                                       proposal := fmt.Sprintf("%s %d", ifname, j+1)
+                                       if proposal == availableIfname {
+                                               continue
+                                       }
+                                       err2 = nci.SetConnectionName(duplicateGuid, proposal)
+                                       if err2 == windows.ERROR_DUP_NAME {
+                                               continue
+                                       }
+                                       if err2 == nil {
+                                               err = nci.SetConnectionName(&wintun.cfgInstanceID, availableIfname)
+                                               if err == nil {
+                                                       break setloop
+                                               }
+                                       }
+                                       break
+                               }
+                       }
+               }
+
                if i > maxSuffix || err != windows.ERROR_DUP_NAME {
                        return fmt.Errorf("NciSetConnectionName failed: %v", err)
                }