Prefer Cryptodome which is better maintained

beaker/crypto/pycrypto.py

@@ -1,9 +1,44 @@
-"""Encryption module that uses pycryptopp or pycrypto"""
+"""Encryption module that uses cryptodomex, pycryptopp, or pycrypto, whichever is
+available first.
+
+cryptodomex is preferred over Pycryptopp because (as of 2021-01-26) it
+is more actively maintained.
+
+"""
+
+try:
+    import Cryptodome
+    have_cryptodome = True
+except ImportError:
+    have_cryptodome = False
+
 try:
-    # Pycryptopp is preferred over Crypto because Crypto has had
-    # various periods of not being maintained, and pycryptopp uses
-    # the Crypto++ library which is generally considered the 'gold standard'
-    # of crypto implementations
+    import pycryptopp
+    have_pycryptopp = True
+except ImportError:
+    have_pycryptopp = False
+
+try:
+    import Crypto
+    have_pycrypto = True
+except ImportError:
+    have_pycrypto = False
+
+if have_cryptodome:
+    from Cryptodome.Cipher import AES
+    from Cryptodome.Util import Counter
+
+    def aesEncrypt(data, key):
+        cipher = AES.new(key, AES.MODE_CTR,
+                         counter=Counter.new(128, initial_value=0))
+
+        return cipher.encrypt(data)
+
+    def aesDecrypt(data, key):
+        cipher = AES.new(key, AES.MODE_CTR,
+                         counter=Counter.new(128, initial_value=0))
+        return cipher.decrypt(data)
+elif have_pycryptopp:
     from pycryptopp.cipher import aes
 
     def aesEncrypt(data, key):
@@ -12,8 +47,7 @@ def aesEncrypt(data, key):
 
     # magic.
     aesDecrypt = aesEncrypt
-
-except ImportError:
+elif have_pycrypto:
     from Crypto.Cipher import AES
     from Crypto.Util import Counter
 
@@ -27,6 +61,8 @@ def aesDecrypt(data, key):
         cipher = AES.new(key, AES.MODE_CTR,
                          counter=Counter.new(128, initial_value=0))
         return cipher.decrypt(data)
+else:
+    raise Exception("Could not find a suitable module to implement beaker.crypto.pycrypto")
 
 has_aes = True
 

setup.py

@@ -23,7 +23,7 @@
     INSTALL_REQUIRES.append('funcsigs')
 
 
-TESTS_REQUIRE = ['pytest', 'Mock', 'pycryptodome']
+TESTS_REQUIRE = ['pytest', 'Mock', 'pycryptodomex']
 
 if py_version == (2, 6):
     TESTS_REQUIRE.append('WebTest<2.0.24')
@@ -90,7 +90,7 @@
       extras_require={
           'crypto': ['pycryptopp>=0.5.12'],
           'pycrypto': ['pycrypto'],
-          'pycryptodome': ['pycryptodome'],
+          'pycryptodome': ['pycryptodomex'],
           'cryptography': ['cryptography'],
           'testsuite': [TESTS_REQUIRE]
       },