DnsServer/DnsServerCore/Dhcp/NetBiosNameServerOption.cs

/*
Technitium DNS Server
Copyright (C) 2019  Shreyas Zare (shreyas@technitium.com)

This program 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.

This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

*/

using System;
using System.IO;
using System.Net;
using TechnitiumLibrary.IO;

namespace DnsServerCore.Dhcp
{
    class NetBiosNameServerOption : DhcpOption
    {
        #region variables

        readonly IPAddress[] _addresses;

        #endregion

        #region constructor

        public NetBiosNameServerOption(Stream s)
            : base(DhcpOptionCode.NetBiosOverTcpIpNameServer)
        {
            int len = s.ReadByte();
            if (len < 0)
                throw new EndOfStreamException();

            if ((len % 4 != 0) || (len < 4))
                throw new InvalidDataException();

            _addresses = new IPAddress[len / 4];

            for (int i = 0; i < _addresses.Length; i++)
                _addresses[i] = new IPAddress(s.ReadBytes(4));
        }

        #endregion

        #region protected

        protected override void WriteOptionTo(Stream s)
        {
            s.WriteByte(Convert.ToByte(_addresses.Length * 4));

            foreach (IPAddress address in _addresses)
                s.Write(address.GetAddressBytes());
        }

        #endregion

        #region properties

        public IPAddress[] Addresses
        { get { return _addresses; } }

        #endregion
    }
}