public void InvalidNonceSize(int nonceSize)
{
int dataLength = 30;
byte[] plaintext = Enumerable.Range(1, dataLength).Select((x) => (byte)x).ToArray();
byte[] ciphertext = new byte[dataLength];
byte[] key = AesGcmTestHelpers.GetRandomBuffer(16);
byte[] nonce = AesGcmTestHelpers.GetRandomBuffer(nonceSize);
byte[] tag = new byte[AesGcmWindows.TagByteSizes.MinSize];
using (var aesGcm = new AesGcmWindows(key))
{
Assert.Throws <ArgumentException>(() => aesGcm.Encrypt(nonce, plaintext, ciphertext, tag), "nonce");
}
}
public static void InplaceEncryptDecrypt()
{
byte[] key = "d5a194ed90cfe08abecd4691997ceb2c".HexToByteArray();
byte[] nonce = AesGcmTestHelpers.GetRandomBuffer(12);
byte[] originalPlaintext = new byte[] { 1, 2, 8, 12, 16, 99, 0 };
byte[] data = (byte[])originalPlaintext.Clone();
byte[] tag = AesGcmTestHelpers.GetRandomBuffer(16);
using (var aesGcm = new AesGcmWindows(key))
{
aesGcm.Encrypt(nonce, data, data, tag);
Assert.AreNotEqual(originalPlaintext, data);
aesGcm.Decrypt(nonce, data, tag, data);
Assert.AreEqual(originalPlaintext, data);
}
}
public static void ValidTagSize(int tagSize)
{
const int dataLength = 35;
byte[] plaintext = Enumerable.Range(1, dataLength).Select((x) => (byte)x).ToArray();
byte[] ciphertext = new byte[dataLength];
byte[] key = AesGcmTestHelpers.GetRandomBuffer(16);
byte[] nonce = AesGcmTestHelpers.GetRandomBuffer(12);
byte[] tag = new byte[tagSize];
using (var aesGcm = new AesGcmWindows(key))
{
aesGcm.Encrypt(nonce, plaintext, ciphertext, tag);
byte[] decrypted = new byte[dataLength];
aesGcm.Decrypt(nonce, ciphertext, tag, decrypted);
Assert.AreEqual(plaintext, decrypted);
}
}
public static void InplaceEncryptTamperTagDecrypt()
{
byte[] key = "d5a194ed90cfe08abecd4691997ceb2c".HexToByteArray();
byte[] nonce = AesGcmTestHelpers.GetRandomBuffer(12);
byte[] originalPlaintext = new byte[] { 1, 2, 8, 12, 16, 99, 0 };
byte[] data = (byte[])originalPlaintext.Clone();
byte[] tag = new byte[16];
using (var aesGcm = new AesGcmWindows(key))
{
aesGcm.Encrypt(nonce, data, data, tag);
Assert.AreNotEqual(originalPlaintext, data);
tag[0] ^= 1;
Assert.Throws <CryptographicException>(
() => aesGcm.Decrypt(nonce, data, tag, data));
Assert.AreEqual(new byte[data.Length], data);
}
}
public static void AesGcmNistTestsTamperTagVectorSelected()
{
foreach (AeadTest test in s_nistGcmTestVectorsSelectedCases)
{
using (var aesGcm = new AesGcmWindows(test.Key))
{
byte[] ciphertext = new byte[test.Plaintext.Length];
byte[] tag = new byte[test.Tag.Length];
aesGcm.Encrypt(test.Nonce, test.Plaintext, ciphertext, tag, test.AssociatedData);
Assert.AreEqual(test.Ciphertext, ciphertext);
Assert.AreEqual(test.Tag, tag);
tag[0] ^= 1;
byte[] plaintext = AesGcmTestHelpers.GetRandomBuffer(test.Plaintext.Length);
Assert.Throws <CryptographicException>(
() => aesGcm.Decrypt(test.Nonce, ciphertext, tag, plaintext, test.AssociatedData));
Assert.AreEqual(new byte[plaintext.Length], plaintext);
}
}
}
public void EncryptTamperAADDecrypt(int dataLength, int additionalDataLength)
{
byte[] additionalData = AesGcmTestHelpers.GetRandomBuffer(additionalDataLength);
byte[] plaintext = Enumerable.Range(1, dataLength).Select((x) => (byte)x).ToArray();
byte[] ciphertext = new byte[dataLength];
byte[] key = AesGcmTestHelpers.GetRandomBuffer(16);
byte[] nonce = AesGcmTestHelpers.GetRandomBuffer(AesGcmWindows.NonceByteSizes.MinSize);
byte[] tag = new byte[AesGcmWindows.TagByteSizes.MinSize];
using (var aesGcm = new AesGcmWindows(key))
{
aesGcm.Encrypt(nonce, plaintext, ciphertext, tag, additionalData);
additionalData[0] ^= 1;
byte[] decrypted = new byte[dataLength];
Assert.Throws <CryptographicException>(
() => aesGcm.Decrypt(nonce, ciphertext, tag, decrypted, additionalData));
}
}
