Check for correct first nibble

The code before assumed that the flow label was always zero.
2018-04-20 05:30:22 +02:00 · 2018-04-20 05:30:22 +02:00 · f5c256affd
commit f5c256affd
parent 4973ea0c9e
1 changed files with 1 additions and 1 deletions
--- a/tun_linux.go
+++ b/tun_linux.go
@ -273,7 +273,7 @@ func (tun *NativeTun) Write(buff []byte, offset int) (int, error) {
 		buff[0] = 0x00
 		buff[1] = 0x00

-		if buff[4] == ipv6.Version<<4 {
+		if buff[4]>>4 == ipv6.Version {
 			buff[2] = 0x86
 			buff[3] = 0xdd
 		} else {