diff options
| -rw-r--r-- | device/tun.go | 23 |
1 files changed, 15 insertions, 8 deletions
diff --git a/device/tun.go b/device/tun.go index 9ff6c23..17c2493 100644 --- a/device/tun.go +++ b/device/tun.go @@ -6,6 +6,7 @@ package device import ( + "fmt" "sync/atomic" "golang.zx2c4.com/wireguard/tun" @@ -20,16 +21,22 @@ func (device *Device) RoutineTUNEventReader() { for event := range device.tun.device.Events() { if event&tun.EventMTUUpdate != 0 { mtu, err := device.tun.device.MTU() - old := atomic.LoadInt32(&device.tun.mtu) if err != nil { device.log.Errorf("Failed to load updated MTU of device: %v", err) - } else if int(old) != mtu { - if mtu+MessageTransportSize > MaxMessageSize { - device.log.Verbosef("MTU updated: %v (too large)", mtu) - } else { - device.log.Verbosef("MTU updated: %v", mtu) - } - atomic.StoreInt32(&device.tun.mtu, int32(mtu)) + continue + } + if mtu < 0 { + device.log.Errorf("MTU not updated to negative value: %v", mtu) + continue + } + var tooLarge string + if mtu > MaxContentSize { + tooLarge = fmt.Sprintf(" (too large, capped at %v)", MaxContentSize) + mtu = MaxContentSize + } + old := atomic.SwapInt32(&device.tun.mtu, int32(mtu)) + if int(old) != mtu { + device.log.Verbosef("MTU updated: %v%s", mtu, tooLarge) } } |