Я ответил на свой вопрос, создав функцию, которая проверяет, является ли IP-адрес (ipv4 или ipv6) немаршрутизируемым IP-адресом. Я ссылался на статью вики из поста Маккея, чтобы найти много зарезервированных IP-адресов (http://en.wikipedia.org/wiki/Reserved_IP_addresses)
Решение:
/// <summary>
///
/// </summary>
/// <param name="ipAddress"></param>
/// <remarks>A null or empty string passed as the ipAddress will return true. An invalid ipAddress will be returned as true. </remarks>
/// <returns></returns>
public static bool IsNonRoutableIpAddress(string ipAddress)
{
//Reference: http://en.wikipedia.org/wiki/Reserved_IP_addresses
//if the ip address string is empty or null string, we consider it to be non-routable
if (String.IsNullOrEmpty(ipAddress))
{
return true;
}
//if we cannot parse the Ipaddress, then we consider it non-routable
IPAddress tempIpAddress = null;
if (!IPAddress.TryParse(ipAddress, out tempIpAddress))
{
return true;
}
byte[] ipAddressBytes = tempIpAddress.GetAddressBytes();
//if ipAddress is IPv4
if (tempIpAddress.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
{
if (IsIpAddressInRange(ipAddressBytes, "10.0.0.0/8")) //Class A Private network check
{
return true;
}
else if (IsIpAddressInRange(ipAddressBytes, "172.16.0.0/12")) //Class B private network check
{
return true;
}
else if (IsIpAddressInRange(ipAddressBytes, "192.168.0.0/16")) //Class C private network check
{
return true;
}
else if (IsIpAddressInRange(ipAddressBytes, "127.0.0.0/8")) //Loopback
{
return true;
}
else if (IsIpAddressInRange(ipAddressBytes, "0.0.0.0/8")) //reserved for broadcast messages
{
return true;
}
//its routable if its ipv4 and meets none of the criteria
return false;
}
//if ipAddress is IPv6
else if (tempIpAddress.AddressFamily == System.Net.Sockets.AddressFamily.InterNetworkV6)
{
//incomplete
if (IsIpAddressInRange(ipAddressBytes, "::/128")) //Unspecified address
{
return true;
}
else if (IsIpAddressInRange(ipAddressBytes, "::1/128")) //lookback address for localhost
{
return true;
}
else if (IsIpAddressInRange(ipAddressBytes, "2001:db8::/32")) //Addresses used in documentation
{
return true;
}
return false;
}
else
{
//we default to non-routable if its not Ipv4 or Ipv6
return true;
}
}
/// <summary>
///
/// </summary>
/// <param name="ipAddressBytes"></param>
/// <param name="reservedIpAddress"></param>
/// <returns></returns>
private static bool IsIpAddressInRange(byte[] ipAddressBytes, string reservedIpAddress)
{
if (String.IsNullOrEmpty(reservedIpAddress))
{
return false;
}
if (ipAddressBytes == null)
{
return false;
}
//Split the reserved ip address into a bitmask and ip address
string[] ipAddressSplit = reservedIpAddress.Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
if (ipAddressSplit.Length != 2)
{
return false;
}
string ipAddressRange = ipAddressSplit[0];
IPAddress ipAddress = null;
if (!IPAddress.TryParse(ipAddressRange, out ipAddress))
{
return false;
}
// Convert the IP address to bytes.
byte[] ipBytes = ipAddress.GetAddressBytes();
//parse the bits
int bits = 0;
if (!int.TryParse(ipAddressSplit[1], out bits))
{
bits = 0;
}
// BitConverter gives bytes in opposite order to GetAddressBytes().
byte[] maskBytes = null;
if (ipAddress.AddressFamily == AddressFamily.InterNetwork)
{
uint mask = ~(uint.MaxValue >> bits);
maskBytes = BitConverter.GetBytes(mask).Reverse().ToArray();
}
else if (ipAddress.AddressFamily == AddressFamily.InterNetworkV6)
{
//128 places
BitArray bitArray = new BitArray(128, false);
//shift <bits> times to the right
ShiftRight(bitArray, bits, true);
//turn into byte array
maskBytes = ConvertToByteArray(bitArray).Reverse().ToArray();
}
bool result = true;
//Calculate
for (int i = 0; i < ipBytes.Length; i++)
{
result &= (byte)(ipAddressBytes[i] & maskBytes[i]) == ipBytes[i];
}
return result;
}
/// <summary>
///
/// </summary>
/// <param name="bitArray"></param>
/// <param name="shiftN"></param>
/// <param name="fillValue"></param>
private static void ShiftRight(BitArray bitArray, int shiftN, bool fillValue)
{
for (int i = shiftN; i < bitArray.Count; i++)
{
bitArray[i - shiftN] = bitArray[i];
}
//fill the shifted bits as false
for (int index = bitArray.Count - shiftN; index < bitArray.Count; index++)
{
bitArray[index] = fillValue;
}
}
/// <summary>
///
/// </summary>
/// <param name="bitArray"></param>
/// <returns></returns>
private static byte[] ConvertToByteArray(BitArray bitArray)
{
// pack (in this case, using the first bool as the lsb - if you want
// the first bool as the msb, reverse things ;-p)
int bytes = (bitArray.Length + 7) / 8;
byte[] arr2 = new byte[bytes];
int bitIndex = 0;
int byteIndex = 0;
for (int i = 0; i < bitArray.Length; i++)
{
if (bitArray[i])
{
arr2[byteIndex] |= (byte)(1 << bitIndex);
}
bitIndex++;
if (bitIndex == 8)
{
bitIndex = 0;
byteIndex++;
}
}
return arr2;
}