public List <Message> GetDecryptedMessagesWithPrivateKey(string token, string privateKey)
{
var db = new CryptAByteContext();
var request = db.Keys.Include("Messages").SingleOrDefault(key => key.KeyToken == token);
var crypto = new AsymmetricCryptoProvider();
if (!request.IsReleased)
{
throw new ArgumentOutOfRangeException("Request is not released");
}
var plaintextMessages = new List <Message>();
if (request.Messages != null)
{
request.Messages.ToList().ForEach(retrievedMessage =>
{
string messageDecryptionKey;
var decryptedMessage = crypto.DecryptMessageWithKey(privateKey, retrievedMessage.MessageData,
retrievedMessage.EncryptionKey,
retrievedMessage.MessageHash, out messageDecryptionKey);
retrievedMessage.MessageData = decryptedMessage;
retrievedMessage.EncryptionKey = messageDecryptionKey;
if (!retrievedMessage.IsFile)
{
retrievedMessage.MessageData =
GzipCompression.Decompress(retrievedMessage.MessageData);
}
else
{
// this is a zip file
}
plaintextMessages.Add(retrievedMessage);
});
if (request.DeleteMessagesAfterReading || request.DeleteKeyAfterReading)
{
if (request.DeleteMessagesAfterReading || request.DeleteKeyAfterReading)
{
request.Messages.ToList().ForEach(message => db.Messages.Remove(message));
}
if (request.DeleteKeyAfterReading)
{
db.Keys.Remove(request);
}
db.SaveChanges();
}
}
return(plaintextMessages);
}
public void AddRequest(CryptoKey request)
{
// TODO: Validate key
var db = new CryptAByteContext();
db.Keys.Add(request);
db.SaveChanges();
}
private static void AttachDataToKey(string token, string compressedMessage, bool isFile, string encryptionKey = null)
{
string hash = null;
string encryptedPassword;
var db = new CryptAByteContext();
var request = db.Keys.SingleOrDefault(key => key.KeyToken == token);
string encryptedMessage;
if (string.IsNullOrWhiteSpace(encryptionKey))
{
var crypto = new AsymmetricCryptoProvider();
encryptedMessage = crypto.EncryptMessageWithKey(compressedMessage, request.PublicKey, out encryptedPassword,
out hash);
}
else
{
encryptedMessage = compressedMessage;
encryptedPassword = encryptionKey;
}
if (request.Messages == null)
{
request.Messages = new Collection <Message>();
}
request.Messages.Add(new Message()
{
MessageData = encryptedMessage,
EncryptionKey = encryptedPassword,
MessageHash = hash,
Created = DateTime.Now,
IsFile = isFile
});
db.SaveChanges();
}
public void DeleteKeyWithPassphrase(string token, string passphrase)
{
var db = new CryptAByteContext();
var key = db.Keys.Include("Messages").SingleOrDefault(k => k.KeyToken == token);
if (key == null)
{
throw new ArgumentOutOfRangeException("Key for this token not found. Was it already deleted?");
}
var crypto = new SymmetricCryptoProvider();
try
{
var plaintext = crypto.DecryptWithKey(key.PrivateKey, passphrase);
}
catch (ArgumentException)
{
throw new ArgumentException("Failed to verify passphrase. A correct passphrase is required to verify the delete request.");
}
db.Keys.Remove(key);
db.SaveChanges();
}
