device: reduce number of append calls when padding

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
This commit is contained in:
Jason A. Donenfeld 2021-01-29 20:10:48 +01:00
parent de51129e33
commit a9f80d8c58

View file

@ -367,7 +367,7 @@ func calculatePaddingSize(packetSize, mtu int) int {
* Obs. One instance per core
*/
func (device *Device) RoutineEncryption() {
var paddingZeros [PaddingMultiple]byte
var nonce [chacha20poly1305.NonceSize]byte
defer device.log.Verbosef("Routine: encryption worker - stopped")
@ -386,11 +386,8 @@ func (device *Device) RoutineEncryption() {
binary.LittleEndian.PutUint64(fieldNonce, elem.nonce)
// pad content to multiple of 16
paddingSize := calculatePaddingSize(len(elem.packet), int(atomic.LoadInt32(&device.tun.mtu)))
for i := 0; i < paddingSize; i++ {
elem.packet = append(elem.packet, 0)
}
elem.packet = append(elem.packet, paddingZeros[:paddingSize]...)
// encrypt content and release to consumer