public void ServerDecryptionFailsWhenRecordModified()
{
using (Aes128GcmRecordProtection recordProtection = new Aes128GcmRecordProtection(this.masterSecret, this.serverRandom, this.clientRandom))
{
byte[] messageAsBytes = Encoding.UTF8.GetBytes(TestMessage);
Record originalRecord = new Record();
originalRecord.ContentType = ContentType.ApplicationData;
originalRecord.Epoch = 1;
originalRecord.SequenceNumber = 124;
originalRecord.Length = (ushort)recordProtection.GetEncryptedSize(messageAsBytes.Length);
ByteSpan encrypted = new byte[originalRecord.Length];
recordProtection.EncryptServerPlaintext(encrypted, messageAsBytes, ref originalRecord);
ByteSpan plaintext = new byte[recordProtection.GetDecryptedSize(encrypted.Length)];
Record record = originalRecord;
record.ContentType = ContentType.Handshake;
bool couldDecrypt = recordProtection.DecryptCiphertextFromServer(plaintext, encrypted, ref record);
Assert.IsFalse(couldDecrypt);
record = originalRecord;
record.Epoch++;
couldDecrypt = recordProtection.DecryptCiphertextFromServer(plaintext, encrypted, ref record);
Assert.IsFalse(couldDecrypt);
record = originalRecord;
record.SequenceNumber++;
couldDecrypt = recordProtection.DecryptCiphertextFromServer(plaintext, encrypted, ref record);
Assert.IsFalse(couldDecrypt);
}
}
public void ClientCanEncryptAndDecryptData()
{
using (Aes128GcmRecordProtection recordProtection = new Aes128GcmRecordProtection(this.masterSecret, this.serverRandom, this.clientRandom))
{
byte[] messageAsBytes = Encoding.UTF8.GetBytes(TestMessage);
Record record = new Record();
record.ContentType = ContentType.ApplicationData;
record.Epoch = 1;
record.SequenceNumber = 124;
record.Length = (ushort)recordProtection.GetEncryptedSize(messageAsBytes.Length);
ByteSpan encrypted = new byte[record.Length];
recordProtection.EncryptClientPlaintext(encrypted, messageAsBytes, ref record);
ByteSpan plaintext = new byte[recordProtection.GetDecryptedSize(encrypted.Length)];
bool couldDecrypt = recordProtection.DecryptCiphertextFromClient(plaintext, encrypted, ref record);
Assert.IsTrue(couldDecrypt);
Assert.AreEqual(messageAsBytes.Length, plaintext.Length);
Assert.AreEqual(TestMessage, Encoding.UTF8.GetString(plaintext.GetUnderlyingArray(), plaintext.Offset, plaintext.Length));
}
}