public void RsaCryptorTest()
{
using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
{
RSAParameters rsaKeyInfo = rsa.ExportParameters(true);
byte[] data = new byte[100];
new Random().NextBytes(data);
var cryptor = new RsaMachine(rsaKeyInfo);
byte[] encrypted = cryptor.Encrypt(data);
byte[] decrypted = cryptor.Decrypt(encrypted);
Assert.IsTrue(data.SequenceEqual(decrypted));
}
}
public void DsaSignerTest()
{
using (
RSACryptoServiceProvider dsaprovider = new RSACryptoServiceProvider())
{
RSAParameters keys = dsaprovider.ExportParameters(true);
byte[] data = new byte[100];
new Random().NextBytes(data);
RsaMachine signer = new RsaMachine(keys);
HashAlgorithm hasher = MD5.Create();
byte[] signature = signer.Sign(data, hasher);
Assert.IsTrue(signer.CheckSignature(data, hasher, signature));
}
}
/// <summary>
/// Decrypts a file.
/// </summary>
/// <param name="input"><see cref="EncryptedFile"/> that will be decrypted.</param>
/// <param name="output">Output <see cref="Stream"/> where the decrypted file will be written.</param>
/// <param name="reportProgress">Action that is used to report progress of decryption in percentages.</param>
public void Decrypt(EncryptedFile input, Stream output, Action <int> reportProgress = null)
{
BinaryReader reader = new BinaryReader(input.BaseStream);
reader.BaseStream.Position = input.HeaderLength;
output.Position = 0;
BinaryWriter outputWriter = new BinaryWriter(output);
byte[] decryptedAlgKey = new RsaMachine(this.Key).Decrypt(input.EncryptedKey);
reportProgress?.Invoke(35);
IMachine decryptor = null;
if (input.CryptorCode == AesMachine.Signature)
{
decryptor = new AesMachine(decryptedAlgKey, reader.ReadBytes(16));
}
else if (input.CryptorCode == TDesMachine.Signature)
{
decryptor = new TDesMachine(decryptedAlgKey, reader.ReadBytes(16));
}
else if (input.CryptorCode == TwofishMachine.Signature)
{
decryptor = new TwofishMachine(decryptedAlgKey, reader.ReadBytes(16));
}
for (int i = 0; i < input.NumberOfBlocks; i++)
{
int currentBlockSize = BitConverter.ToInt32(reader.ReadBytes(4), 0);
byte[] block = reader.ReadBytes(currentBlockSize);
outputWriter.Write(decryptor.Decrypt(block));
reportProgress?.Invoke((int)(((float)i / (float)input.NumberOfBlocks) * 1000.00));
}
reportProgress?.Invoke(1000);
}
public UserInformation Login(string username, string password, out UserDatabase data)
{
UserDatabase dataComp = new UserDatabase(this.userDatabasePath);
var user = dataComp.GetUser(username);
if (user != null && user.IsPasswordValid(password))
{
var userCert = new X509Certificate2(user.PublicCertificate);
if (userCert == null)
{
throw new Exception("Certificate error.");
}
if (CertificateValidator.VerifyCertificate(userCert) == false)
{
throw new Exception("Certificate is invalid.");
}
byte[] keyRaw = File.ReadAllBytes(this.privateKeyPath);
var privateParameters = new KeyFileParser(keyRaw).GetParameters();
RSACryptoServiceProvider publicKeyProvider = (RSACryptoServiceProvider)userCert.PublicKey.Key;
if (!RsaMachine.AreKeysMatched(publicKeyProvider.ExportParameters(false), privateParameters))
{
throw new Exception("The given private key does not match this user's certificate.");
}
data = dataComp;
return(new UserInformation(user, privateParameters));
}
else
{
throw new Exception("Invalid username or password.");
}
}
/// <summary>
/// Encrypts a file using a combination of an encryption and a hash algorithm.
/// </summary>
/// <param name="input"><see cref="OriginalFile"/> to be encrypted.</param>
/// <param name="output">Output <see cref="Stream"/> where the encrypted file will be written.</param>
/// <param name="algs">Combination of an encryption and a hash algorithm.</param>
/// <param name="reportProgress">Action used to report progress somewhere.</param>
public void Encrypt(OriginalFile input, Stream output, CryptCombo algs, Action <int> reportProgress = null)
{
BinaryWriter writer = new BinaryWriter(output); // to write to output
BinaryReader reader = new BinaryReader(input.FileContent);
writer.Seek(0, SeekOrigin.Begin); // write to beginning, this will override if there is something there
reader.BaseStream.Position = 0; // read from beginning
long numberOfBlocks = input.FileContent.Length / algs.Machine.BlockSize;
if (numberOfBlocks * algs.Machine.BlockSize < input.FileContent.Length)
{
numberOfBlocks++;
}
var algKey = algs.Machine.Key;
var cryptedkey = new RsaMachine(this.ReceiverPublicKey).Encrypt(algKey);
byte[] header = new byte[] { };
header = header // we concat here instead of writing directly so we can calculate hash
.Concat(Helpers.MagicBytes)
.Concat(Encoding.ASCII.GetBytes(algs.Machine.GetSignatureString()))
.Concat(Encoding.ASCII.GetBytes(Helpers.GetCodeFromHasher(algs.Hasher)))
.Concat(BitConverter.GetBytes(cryptedkey.Length))
.Concat(cryptedkey)
.Concat(BitConverter.GetBytes(input.Extension.Length))
.Concat(Encoding.ASCII.GetBytes(input.Extension))
.Concat(BitConverter.GetBytes(numberOfBlocks))
.ToArray();
var contentHashAggregate = algs.Hasher.ComputeHash(header);
writer.Write(header);
reportProgress?.Invoke(25);
byte[] additionalData = algs.Machine.AdditionalData;
if (additionalData != null)
{
contentHashAggregate = algs.Hasher.ComputeHash(contentHashAggregate.Concat(algs.Hasher.ComputeHash(additionalData)).ToArray());
writer.Write(additionalData);
}
reportProgress?.Invoke(30);
for (int i = 0; i < numberOfBlocks; i++)
{
byte[] buffer = reader.ReadBytes(algs.Machine.BlockSize);
byte[] encryptedBlock = algs.Machine.Encrypt(buffer);
byte[] encSize = BitConverter.GetBytes(encryptedBlock.Length);
byte[] blockToWrite = encSize.Concat(encryptedBlock).ToArray();
contentHashAggregate = algs.Hasher.ComputeHash(contentHashAggregate.Concat(algs.Hasher.ComputeHash(blockToWrite)).ToArray());
writer.Write(blockToWrite);
int progress = (int)(((float)i / (float)numberOfBlocks) * 1000.00);
reportProgress?.Invoke(progress < 980 ? progress : 980);
}
byte[] rsaSignature = new RsaMachine(this.SenderPrivateKey).Sign(contentHashAggregate, algs.Hasher);
reportProgress?.Invoke(990);
writer.Write(rsaSignature.Length);
writer.Write(rsaSignature);
reportProgress?.Invoke(1000);
}