/*
* Copyright (c) 2019-2021 David Timber <mieabby@gmail.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#pragma once
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>

#include "protocol.h"


// Workaround for header issues in uClibc
typedef struct prne_iphdr4 prne_iphdr4_t;
typedef struct prne_iphdr6 prne_iphdr6_t;

struct prne_iphdr4 {
	uint8_t saddr[4];
	uint8_t daddr[4];
	uint16_t total_len;
	uint16_t id;
	uint8_t ttl;
	uint8_t protocol;
	uint8_t ihl;
};

struct prne_iphdr6 {
	uint8_t saddr[16];
	uint8_t daddr[16];
	uint32_t flow_label;
	uint16_t payload_len;
	uint8_t next_hdr;
	uint8_t hop_limit;
};

void prne_netmask_from_cidr (uint8_t *out, size_t cidr);
uint16_t prne_calc_tcp_chksum4 (
	const prne_iphdr4_t *ih,
	const uint8_t *th,
	size_t th_len,
	const uint8_t *data,
	size_t data_len);
uint16_t prne_calc_tcp_chksum6 (
	const prne_iphdr6_t *ih,
	const uint8_t *th,
	size_t th_len,
	const uint8_t *data,
	size_t data_len);

void prne_ser_iphdr4 (uint8_t *mem, const prne_iphdr4_t *in);
void prne_ser_iphdr6 (uint8_t *mem, const prne_iphdr6_t *in);

void prne_dser_iphdr4 (const uint8_t *data, prne_iphdr4_t *out);
void prne_dser_iphdr6 (const uint8_t *data, prne_iphdr6_t *out);