CTA_PROTOINFO_TCP_UNSPEC		0
CTA_PROTOINFO_TCP_STATE			1
CTA_PROTOINFO_TCP_WSCALE_ORIGINAL	2
CTA_PROTOINFO_TCP_WSCALE_REPLY		3
CTA_PROTOINFO_TCP_FLAGS_ORIGINAL	4
CTA_PROTOINFO_TCP_FLAGS_REPLY		5