// 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.
enum Direction {
    INCOMING = 0;
    OUTGOING = 1;
};

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

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

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

/// Rule describes the conditions and the action of a rule.
struct Rule {
    Action action;
    Direction direction;
    /// If true, no more rules will be tested.
    bool quick;
    SocketProtocol proto;
    fuchsia.net.Subnet? src_subnet;
    /// If true, matches any address that is NOT contained in the subnet.
    bool src_subnet_invert_match;
    PortRange src_port_range;
    fuchsia.net.Subnet? dst_subnet;
    /// If true, matches any address that is NOT contained in the subnet.
    bool dst_subnet_invert_match;
    PortRange dst_port_range;
    uint32 nic;
    bool log;
    bool keep_state;
};

/// NAT is a special rule for Network Address Translation, which rewrites
/// the address of an outgoing packet.
struct Nat {
    SocketProtocol proto;
    fuchsia.net.Subnet src_subnet;
    fuchsia.net.IpAddress new_src_addr;
    uint32 nic;
};

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