int bridge add name=bridge1
int bridge port add interface=ether1 bridge=bridge1
int bridge port add interface=ether2 bridge=bridge1
int bridge port add interface=ether3 bridge=bridge1
int bridge port add interface=ether4 bridge=bridge1
int bridge port add interface=ether5 bridge=bridge1
int bridge filter add chain=forward out-interface=!ether1 in-interface=ether2 action=drop
int bridge filter add chain=forward out-interface=!ether1 in-interface=ether3 action=drop
int bridge filter add chain=forward out-interface=!ether1 in-interface=ether4 action=drop
int bridge filter add chain=forward out-interface=!ether1 in-interface=ether5 action=drop