ntp.cpp

/*
	This file is part of Fennix Kernel.

	Fennix Kernel is free software: you can redistribute it and/or
	modify it under the terms of the GNU General Public License as
	published by the Free Software Foundation, either version 3 of
	the License, or (at your option) any later version.

	Fennix Kernel is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
*/

#include <net/ntp.hpp>
#include <debug.h>

#include "../kernel.h"

namespace NetworkNTP
{
	void NTP::OnUDPPacketReceived(NetworkUDP::Socket *Socket, uint8_t *Data, size_t Length)
	{
		UNUSED(Socket);
		UNUSED(Length);
		this->NTPPacket = *(NTPHeader *)Data;
		this->TimeReceived = true;
		netdbg("Received UDP packet for NTP.");
	}

	NTP::NTP(NetworkUDP::Socket *Socket) : NetworkUDP::UDPEvents()
	{
		debug("NTP interface %#lx created.", this);
		this->UDPSocket = Socket;
	}

	NTP::~NTP()
	{
		debug("NTP interface %#lx destroyed.", this);
	}

	int NTP::ReadTime()
	{
		netdbg("Requesting time");
		this->TimeReceived = false;

		NTPHeader ReqPacket;                      // This may require physical memory allocation but Ethernet already has this job.
		memset(&ReqPacket, 0, sizeof(NTPHeader)); // Zero out the packet
		*((char *)&ReqPacket) = 0x1b;             // byteswap nightmare, this is the code below but in little endian
		// ReqPacket.LeapIndicator = 0;
		// ReqPacket.VersionNumber = 3;
		// ReqPacket.Mode = 3;
		UDPSocket->SocketUDP->Send(UDPSocket, (uint8_t *)&ReqPacket, sizeof(NTPHeader));

		debug("Waiting for response...");
		int RequestTimeout = 20;
		while (!this->TimeReceived)
		{
			if (--RequestTimeout == 0)
			{
				warn("Request timeout.");
				return 0;
			}
			netdbg("Still waiting...");
			TaskManager->Sleep(1000);
		}

		uint64_t UnixTimestamp = (b32(this->NTPPacket.TransmitTimestamp[0])) - 2208988800;
		debug("Unix time: %d", UnixTimestamp);
		return s_cst(int, UnixTimestamp);
	}
}