// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library fuchsia.net.filter;

using fuchsia.net;

/// Direction is which way (Incoming or Outgoing) a packet is moving in the stack.
type Direction = strict enum {
    INCOMING = 0;
    OUTGOING = 1;
};

type Action = strict enum {
    PASS = 0;
    DROP = 1;
    DROP_RESET = 2;
};

type SocketProtocol = strict enum {
    ANY = 0;
    ICMP = 1;
    TCP = 2;
    UDP = 3;
    ICMPV6 = 4;
};

/// PortRange specifies an inclusive range of port numbers.
type PortRange = struct {
    start uint16;
    end uint16;
};

/// Rule describes the conditions and the action of a rule.
type Rule = struct {
    action Action;
    direction Direction;
    proto SocketProtocol;
    src_subnet box<fuchsia.net.Subnet>;
    /// If true, matches any address that is NOT contained in the subnet.
    src_subnet_invert_match bool;
    src_port_range PortRange;
    dst_subnet box<fuchsia.net.Subnet>;
    /// If true, matches any address that is NOT contained in the subnet.
    dst_subnet_invert_match bool;
    dst_port_range PortRange;
    nic uint32;
    log bool;
    keep_state bool;
};

/// NAT is a rule for Source Network Address Translation.
///
/// The source address of packets matching the rule will updated to an address
/// belonging to the outgoing interface.
type Nat = struct {
    proto SocketProtocol;
    src_subnet fuchsia.net.Subnet;
    outgoing_nic uint32;
};

/// RDR is a special rule for Redirector, which forwards an incoming packet
/// to a machine inside the firewall.
type Rdr = struct {
    proto SocketProtocol;
    dst_addr fuchsia.net.IpAddress;
    dst_port_range PortRange;
    new_dst_addr fuchsia.net.IpAddress;
    new_dst_port_range PortRange;
    nic uint32;
};