Python: Add working tests of AES and RC4

RasmusWL · RasmusWL · commit d18fbb7f07ee · 2021-04-22T14:51:14.000+02:00
diff --git a/python/ql/test/experimental/library-tests/frameworks/cryptodome/test_aes.py b/python/ql/test/experimental/library-tests/frameworks/cryptodome/test_aes.py
@@ -0,0 +1,36 @@
+# https://pycryptodome.readthedocs.io/en/latest/src/cipher/aes.html
+from Cryptodome.Cipher import AES
+
+import os
+
+key = os.urandom(256//8)
+iv = os.urandom(16)
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+
+print("encrypt/decrypt")
+
+secret_message = b"secret message"
+
+padding_len = 16 - (len(secret_message) % 16)
+padding = b"\0"*padding_len
+
+cipher = AES.new(key, AES.MODE_CBC, iv=iv)
+# using separate .encrypt calls on individual lines does not work
+whole_plantext = secret_message + padding
+encrypted = cipher.encrypt(whole_plantext)
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+cipher = AES.new(key, AES.MODE_CBC, iv=iv)
+decrypted = cipher.decrypt(encrypted)
+
+decrypted = decrypted[:-padding_len]
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
diff --git a/python/ql/test/experimental/library-tests/frameworks/cryptodome/test_rc4.py b/python/ql/test/experimental/library-tests/frameworks/cryptodome/test_rc4.py
@@ -0,0 +1,30 @@
+# https://pycryptodome.readthedocs.io/en/latest/src/cipher/arc4.html
+from Cryptodome.Cipher import ARC4
+
+import os
+
+key = os.urandom(256//8)
+
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+
+
+print("encrypt/decrypt")
+
+secret_message = b"secret message"
+
+cipher = ARC4.new(key)
+encrypted = cipher.encrypt(secret_message)
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+cipher = ARC4.new(key)
+decrypted = cipher.decrypt(encrypted)
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
diff --git a/python/ql/test/experimental/library-tests/frameworks/cryptography/test_aes.py b/python/ql/test/experimental/library-tests/frameworks/cryptography/test_aes.py
@@ -0,0 +1,40 @@
+from cryptography.hazmat.primitives.ciphers import algorithms, Cipher, modes
+import os
+
+key = os.urandom(256//8)
+iv = os.urandom(16)
+
+algorithm = algorithms.AES(key)
+cipher = Cipher(algorithm, mode=modes.CBC(iv))
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+# following https://cryptography.io/en/latest/hazmat/primitives/symmetric-encryption/#cryptography.hazmat.primitives.ciphers.Cipher
+
+print("encrypt/decrypt")
+
+secret_message = b"secret message"
+
+padding_len = 16 - (len(secret_message) % 16)
+padding = b"\0"*padding_len
+
+encryptor = cipher.encryptor()
+print(padding_len)
+encrypted = encryptor.update(secret_message)
+encrypted += encryptor.update(padding)
+encrypted += encryptor.finalize()
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+decryptor = cipher.decryptor()
+decrypted = decryptor.update(encrypted)
+decrypted += decryptor.finalize()
+
+decrypted = decrypted[:-padding_len]
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
diff --git a/python/ql/test/experimental/library-tests/frameworks/cryptography/test_rc4.py b/python/ql/test/experimental/library-tests/frameworks/cryptography/test_rc4.py
@@ -0,0 +1,32 @@
+from cryptography.hazmat.primitives.ciphers import algorithms, Cipher
+import os
+
+key = os.urandom(256//8)
+
+algorithm = algorithms.ARC4(key)
+cipher = Cipher(algorithm, mode=None)
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+# following https://cryptography.io/en/latest/hazmat/primitives/symmetric-encryption.html#cryptography.hazmat.primitives.ciphers.algorithms.ARC4
+
+print("encrypt/decrypt")
+
+secret_message = b"secret message"
+
+encryptor = cipher.encryptor()
+encrypted = encryptor.update(secret_message)
+encrypted += encryptor.finalize()
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+decryptor = cipher.decryptor()
+decrypted = decryptor.update(encrypted)
+decrypted += decryptor.finalize()
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
