GenerateTransactionID generates a random 32-bits number suitable for use as TransactionID.

MakeBroadcastSocket creates a socket that can be passed to unix.Sendto that will send packets out to the broadcast address.

MakeRawUDPPacket converts a payload (a serialized packet) into a raw UDP packet for the specified serverAddr from the specified clientAddr.

returns a reader which should always be closed, even if we return an error.

Linux specific returns a writer which should always be closed, even if we return an error.

TransactionID represents a 4-byte DHCP transaction ID as defined in RFC 951, Section 3.