// Copyright 2020 The gVisor Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package ip

import "gvisor.dev/gvisor/pkg/tcpip"

// LINT.IfChange(MultiCounterIPStats)

// MultiCounterIPStats holds IP statistics, each counter may have several
// versions.
type MultiCounterIPStats struct {
	// PacketsReceived is the total number of IP packets received from the link
	// layer.
	PacketsReceived tcpip.MultiCounterStat

	// DisabledPacketsReceived is the total number of IP packets received from the
	// link layer when the IP layer is disabled.
	DisabledPacketsReceived tcpip.MultiCounterStat

	// InvalidDestinationAddressesReceived is the total number of IP packets
	// received with an unknown or invalid destination address.
	InvalidDestinationAddressesReceived tcpip.MultiCounterStat

	// InvalidSourceAddressesReceived is the total number of IP packets received
	// with a source address that should never have been received on the wire.
	InvalidSourceAddressesReceived tcpip.MultiCounterStat

	// PacketsDelivered is the total number of incoming IP packets that are
	// successfully delivered to the transport layer.
	PacketsDelivered tcpip.MultiCounterStat

	// PacketsSent is the total number of IP packets sent via WritePacket.
	PacketsSent tcpip.MultiCounterStat

	// OutgoingPacketErrors is the total number of IP packets which failed to
	// write to a link-layer endpoint.
	OutgoingPacketErrors tcpip.MultiCounterStat

	// MalformedPacketsReceived is the total number of IP Packets that were
	// dropped due to the IP packet header failing validation checks.
	MalformedPacketsReceived tcpip.MultiCounterStat

	// MalformedFragmentsReceived is the total number of IP Fragments that were
	// dropped due to the fragment failing validation checks.
	MalformedFragmentsReceived tcpip.MultiCounterStat

	// IPTablesPreroutingDropped is the total number of IP packets dropped in the
	// Prerouting chain.
	IPTablesPreroutingDropped tcpip.MultiCounterStat

	// IPTablesInputDropped is the total number of IP packets dropped in the Input
	// chain.
	IPTablesInputDropped tcpip.MultiCounterStat

	// IPTablesOutputDropped is the total number of IP packets dropped in the
	// Output chain.
	IPTablesOutputDropped tcpip.MultiCounterStat

	// TODO(https://gvisor.dev/issues/5529): Move the IPv4-only option stats out
	// of IPStats.

	// OptionTimestampReceived is the number of Timestamp options seen.
	OptionTimestampReceived tcpip.MultiCounterStat

	// OptionRecordRouteReceived is the number of Record Route options seen.
	OptionRecordRouteReceived tcpip.MultiCounterStat

	// OptionRouterAlertReceived is the number of Router Alert options seen.
	OptionRouterAlertReceived tcpip.MultiCounterStat

	// OptionUnknownReceived is the number of unknown IP options seen.
	OptionUnknownReceived tcpip.MultiCounterStat
}

// Init sets internal counters to track a and b counters.
func (m *MultiCounterIPStats) Init(a, b *tcpip.IPStats) {
	m.PacketsReceived.Init(a.PacketsReceived, b.PacketsReceived)
	m.DisabledPacketsReceived.Init(a.DisabledPacketsReceived, b.DisabledPacketsReceived)
	m.InvalidDestinationAddressesReceived.Init(a.InvalidDestinationAddressesReceived, b.InvalidDestinationAddressesReceived)
	m.InvalidSourceAddressesReceived.Init(a.InvalidSourceAddressesReceived, b.InvalidSourceAddressesReceived)
	m.PacketsDelivered.Init(a.PacketsDelivered, b.PacketsDelivered)
	m.PacketsSent.Init(a.PacketsSent, b.PacketsSent)
	m.OutgoingPacketErrors.Init(a.OutgoingPacketErrors, b.OutgoingPacketErrors)
	m.MalformedPacketsReceived.Init(a.MalformedPacketsReceived, b.MalformedPacketsReceived)
	m.MalformedFragmentsReceived.Init(a.MalformedFragmentsReceived, b.MalformedFragmentsReceived)
	m.IPTablesPreroutingDropped.Init(a.IPTablesPreroutingDropped, b.IPTablesPreroutingDropped)
	m.IPTablesInputDropped.Init(a.IPTablesInputDropped, b.IPTablesInputDropped)
	m.IPTablesOutputDropped.Init(a.IPTablesOutputDropped, b.IPTablesOutputDropped)
	m.OptionTimestampReceived.Init(a.OptionTimestampReceived, b.OptionTimestampReceived)
	m.OptionRecordRouteReceived.Init(a.OptionRecordRouteReceived, b.OptionRecordRouteReceived)
	m.OptionRouterAlertReceived.Init(a.OptionRouterAlertReceived, b.OptionRouterAlertReceived)
	m.OptionUnknownReceived.Init(a.OptionUnknownReceived, b.OptionUnknownReceived)
}

// LINT.ThenChange(:MultiCounterIPStats, ../../../tcpip.go:IPStats)