/// <summary>
/// ValidateKey method implmentation
/// </summary>
public bool ValidateKey(string upn)
{
if (string.IsNullOrEmpty(upn))
{
return(false);
}
string lupn = upn.ToLower();
string key = ReadKey(lupn);
if (string.IsNullOrEmpty(key))
{
return(false);
}
if (HasStorageInfos(key))
{
byte[] crypted = StripStorageInfos(key);
if (crypted == null)
{
return(false);
}
using (var prov = new AES256CNGEncryption(XORSecret))
{
byte[] cleared = prov.GetDecryptedKey(crypted, lupn);
if (cleared == null)
{
return(false); // Key corrupted
}
if (prov.CheckSum == null)
{
return(false); // Key corrupted
}
if (prov.CheckSum.SequenceEqual(CheckSumEncoding.CheckSum(lupn)))
{
return(true); // OK
}
else
{
return(false); // Key corrupted
}
}
}
else
{
return(false);
}
}
/// <summary>
/// ProbeKey method implmentation
/// </summary>
public byte[] ProbeKey(string upn)
{
if (string.IsNullOrEmpty(upn))
{
return(null);
}
string lupn = upn.ToLower();
string key = ReadKey(lupn);
if (string.IsNullOrEmpty(key))
{
return(null);
}
byte[] probed = null;
byte[] crypted = StripStorageInfos(key);
if (crypted == null)
{
return(null);
}
using (var prov = new AES256CNGEncryption(XORSecret))
{
probed = prov.GetDecryptedKey(crypted, lupn);
if (probed == null)
{
return(null);
}
}
if (probed.Length > MAX_PROBE_LEN)
{
byte[] buffer = new byte[MAX_PROBE_LEN];
Buffer.BlockCopy(probed, 0, buffer, 0, MAX_PROBE_LEN);
return(buffer);
}
else
{
return(probed);
}
}