/// <summary>
/// Method adds provided IP address and range to the whitelist
/// </summary>
/// <param name="ip">IP address we are adding to the whitelist</param>
/// <param name="bits">network bits of the address. This is used to calculate upper and lower IP address of the range.</param>
/// <returns>true if ip was added, false if it allready exist in the whitelist</returns>
public bool AddWhiteList(IPAddress ip, int bits)
{
IpNumber _IP = GetIpRangeFromIpAddress(ip, bits);
if (!_whiteList.ContainsKey(ip.ToString()))
{
_whiteList.Add(ip.ToString(), _IP);
return(true);
}
return(false);
}
/// <summary>
/// Internal helper method to check if provided ip is in range of provided filter.
/// </summary>
/// <param name="ip">IP address we are checking in byte format.</param>
/// <param name="filter">Ip filter (IP range) we are checking against</param>
/// <returns>true if ip is in range, false if it is not.</returns>
private bool IpInRange(byte[] ip, IpNumber filter)
{
bool _result = true;
for (int i = 0; i < ip.Length; i++)
{
if ((ip[i] >= filter.IPAddressLower[i]) && (ip[i] <= filter.IPAddressUpper[i]))
{
//
}
else
{
_result = false;
}
}
return(_result);
}
/// <summary>
/// internal helper method that calculates upper and lower ip address of ip range, from provided IP address and nework bit mask.
/// ip if provided as IPAddress class and mask is provided as bits (for example: 0, 8, 16, 24, 32, ...)
/// </summary>
/// <param name="ip">IP to be used for range caclulation</param>
/// <param name="bits">Network bits to be used for range calculation</param>
/// <returns>IPNumber filter object contain provided ip address and upper and lowe ranges of the network</returns>
private IpNumber GetIpRangeFromIpAddress(IPAddress ip, int bits)
{
uint _IPMask;
if (bits != 32)
{
_IPMask = ~(uint.MaxValue >> bits);
}
else
{
_IPMask = uint.MaxValue;
}
byte[] _ipBytes = ip.GetAddressBytes();
byte[] _maskBytes;
if (BitConverter.IsLittleEndian)
{
_maskBytes = BitConverter.GetBytes(_IPMask).Reverse().ToArray();
}
else
{
_maskBytes = BitConverter.GetBytes(_IPMask).ToArray();
}
byte[] _lowerIPBytes = new byte[_ipBytes.Length];
byte[] _upperIPBytes = new byte[_ipBytes.Length];
for (int i = 0; i < _ipBytes.Length; i++)
{
_lowerIPBytes[i] = (byte)(_ipBytes[i] & _maskBytes[i]);
_upperIPBytes[i] = (byte)(_ipBytes[i] | ~_maskBytes[i]);
}
IpNumber _IP = new IpNumber();
_IP.IPAddress = _ipBytes;
_IP.IPAddressLower = _lowerIPBytes;
_IP.IPAddressUpper = _upperIPBytes;
return(_IP);
}
