+ @param is_twicenat - 1 if session is twice-nat
+ @param ext_host_valid - 1 if external host address and port are valid
+ @param ext_host_address - external host IPv4 address
+ @param ext_host_port - external host port
+ @param ext_host_nat_address - post-NAT external host IPv4 address (valid
+ only if twice-nat session)
+ @param ext_host_nat_port - post-NAT external host port (valid only if
+ twice-nat session)