Adds Cryptographer unit tests

test/unit/test_cryptographer.py

@@ -0,0 +1,51 @@
+import binascii
+
+from pisa.cryptographer import Cryptographer
+from pisa.encrypted_blob import EncryptedBlob
+from test.unit.conftest import get_random_value_hex
+
+data = "6097cdf52309b1b2124efeed36bd34f46dc1c25ad23ac86f28380f746254f777"
+key = "b2e984a570f6f49bc38ace178e09147b0aa296cbb7c92eb01412f7e2d07b5659"
+encrypted_data = "092e93d4a34aac4367075506f2c050ddfa1a201ee6669b65058572904dcea642aeb01ea4b57293618e8c46809dfadadc"
+encrypted_blob = EncryptedBlob(encrypted_data)
+
+
+# TODO: The decryption tests are assuming the cipher is AES-GCM-128, since EncryptedBlob assumes the same. Fix this.
+def test_decrypt_wrong_data():
+    random_key = get_random_value_hex(32)
+    random_encrypted_data = get_random_value_hex(64)
+    random_encrypted_blob = EncryptedBlob(random_encrypted_data)
+
+    # Trying to decrypt random data (in AES_GCM-128) should result in an InvalidTag exception. Our decrypt function
+    # returns None
+    hex_tx = Cryptographer.decrypt(random_encrypted_blob, random_key)
+    assert hex_tx is None
+
+
+def test_decrypt_odd_length():
+    random_key = get_random_value_hex(32)
+    random_encrypted_data_odd = get_random_value_hex(64)[:-1]
+    random_encrypted_blob_odd = EncryptedBlob(random_encrypted_data_odd)
+
+    assert Cryptographer.decrypt(random_encrypted_blob_odd, random_key) is None
+
+
+def test_decrypt_hex():
+    # Valid data should run with no InvalidTag and verify
+    assert Cryptographer.decrypt(encrypted_blob, key) == data
+
+
+def test_decrypt_bytes():
+    # We can also get the decryption in bytes
+    byte_blob = Cryptographer.decrypt(encrypted_blob, key, rtype="bytes")
+    assert isinstance(byte_blob, bytes) and byte_blob == binascii.unhexlify(data)
+
+
+def test_decrypt_wrong_return():
+    # Any other type but "hex" (default) or "bytes" should fail
+    try:
+        Cryptographer.decrypt(encrypted_blob, key, rtype="random_value")
+        assert False
+
+    except ValueError:
+        assert True