ipv4.h

// (C) 2020-2023 by folkert van heusden <mail@vanheusden.com>, released under Apache License v2.0
#pragma once

#include <atomic>
#include <map>
#include <optional>
#include <stdint.h>
#include <string>

#include "duration_events.h"
#include "network_layer.h"
#include "phys.h"
#include "router.h"
#include "stats.h"
#include "transport_layer.h"


class arp;

class ipv4 : public network_layer
{
private:
	std::vector<std::thread *> ths;

	arp  *const iarp { nullptr };

	const any_addr myip;

	const bool     forward  { false   };

	uint64_t *ip_n_pkt      { nullptr };
	uint64_t *ip_n_disc     { nullptr };
	uint64_t *ip_n_del      { nullptr };
	uint64_t *ip_n_out_req  { nullptr };
	uint64_t *ip_n_out_disc { nullptr };
	uint64_t *ipv4_n_pkt    { nullptr };
	uint64_t *ipv4_not_me   { nullptr };
	uint64_t *ipv4_ttl_ex   { nullptr };
	uint64_t *ipv4_unk_prot { nullptr };
	uint64_t *ipv4_n_tx     { nullptr };
	uint64_t *ipv4_tx_err   { nullptr };

	duration_events transmit_packet_de { "ipv4: transmit packet", 8 };
	duration_events receive_packet_de  { "ipv4: receive packet", 8 };

	void send_ttl_exceeded(const packet *const pkt) const;

public:
	ipv4(stats *const s, arp *const iarp, const any_addr & myip, router *const r, const bool forward, const int n_threads);
	virtual ~ipv4();

	any_addr get_addr() const override { return myip; }

	bool transmit_packet(const std::optional<any_addr> & dst_mac, const any_addr & dst_ip, const any_addr & src_ip, const uint8_t protocol, const uint8_t *payload, const size_t pl_size, const uint8_t *const header_template) override;

	virtual int get_max_packet_size() const override { return default_pdev->get_max_packet_size() - 20 /* 20 = size of IPv4 header (without options, as MyIP does) */; }

	void operator()() override;
};