water/waterutil/tun_ipv4.go
2013-03-25 14:49:39 -05:00

38 lines
700 B
Go

package waterutil
import (
"net"
)
func IPv4DSCP(packet []byte) byte {
return packet[1] >> 2
}
func IPv4ECN(packet []byte) byte {
return packet[1] & 0x03
}
func IPv4Identification(packet []byte) [2]byte {
return [2]byte{packet[4], packet[5]}
}
func IPv4TTL(packet []byte) byte {
return packet[8]
}
func IPv4Protocol(packet []byte) IPProtocol {
return IPProtocol(packet[9])
}
func IPv4Source(packet []byte) net.IP {
return net.IPv4(packet[12], packet[13], packet[14], packet[15])
}
func IPv4Destination(packet []byte) net.IP {
return net.IPv4(packet[16], packet[17], packet[18], packet[19])
}
func IPv4Payload(packet []byte) []byte {
ihl := packet[0] & 0x0F
return packet[ihl*4:]
}