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python/gdata/tlslite/utils/cipherfactory.py

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+"""Factory functions for symmetric cryptography."""
+
+import os
+
+import Python_AES
+import Python_RC4
+
+import cryptomath
+
+tripleDESPresent = False
+
+if cryptomath.m2cryptoLoaded:
+    import OpenSSL_AES
+    import OpenSSL_RC4
+    import OpenSSL_TripleDES
+    tripleDESPresent = True
+
+if cryptomath.cryptlibpyLoaded:
+    import Cryptlib_AES
+    import Cryptlib_RC4
+    import Cryptlib_TripleDES
+    tripleDESPresent = True
+
+if cryptomath.pycryptoLoaded:
+    import PyCrypto_AES
+    import PyCrypto_RC4
+    import PyCrypto_TripleDES
+    tripleDESPresent = True
+
+# **************************************************************************
+# Factory Functions for AES
+# **************************************************************************
+
+def createAES(key, IV, implList=None):
+    """Create a new AES object.
+
+    @type key: str
+    @param key: A 16, 24, or 32 byte string.
+
+    @type IV: str
+    @param IV: A 16 byte string
+
+    @rtype: L{tlslite.utils.AES}
+    @return: An AES object.
+    """
+    if implList == None:
+        implList = ["cryptlib", "openssl", "pycrypto", "python"]
+
+    for impl in implList:
+        if impl == "cryptlib" and cryptomath.cryptlibpyLoaded:
+            return Cryptlib_AES.new(key, 2, IV)
+        elif impl == "openssl" and cryptomath.m2cryptoLoaded:
+            return OpenSSL_AES.new(key, 2, IV)
+        elif impl == "pycrypto" and cryptomath.pycryptoLoaded:
+            return PyCrypto_AES.new(key, 2, IV)
+        elif impl == "python":
+            return Python_AES.new(key, 2, IV)
+    raise NotImplementedError()
+
+def createRC4(key, IV, implList=None):
+    """Create a new RC4 object.
+
+    @type key: str
+    @param key: A 16 to 32 byte string.
+
+    @type IV: object
+    @param IV: Ignored, whatever it is.
+
+    @rtype: L{tlslite.utils.RC4}
+    @return: An RC4 object.
+    """
+    if implList == None:
+        implList = ["cryptlib", "openssl", "pycrypto", "python"]
+
+    if len(IV) != 0:
+        raise AssertionError()
+    for impl in implList:
+        if impl == "cryptlib" and cryptomath.cryptlibpyLoaded:
+            return Cryptlib_RC4.new(key)
+        elif impl == "openssl" and cryptomath.m2cryptoLoaded:
+            return OpenSSL_RC4.new(key)
+        elif impl == "pycrypto" and cryptomath.pycryptoLoaded:
+            return PyCrypto_RC4.new(key)
+        elif impl == "python":
+            return Python_RC4.new(key)
+    raise NotImplementedError()
+
+#Create a new TripleDES instance
+def createTripleDES(key, IV, implList=None):
+    """Create a new 3DES object.
+
+    @type key: str
+    @param key: A 24 byte string.
+
+    @type IV: str
+    @param IV: An 8 byte string
+
+    @rtype: L{tlslite.utils.TripleDES}
+    @return: A 3DES object.
+    """
+    if implList == None:
+        implList = ["cryptlib", "openssl", "pycrypto"]
+
+    for impl in implList:
+        if impl == "cryptlib" and cryptomath.cryptlibpyLoaded:
+           return Cryptlib_TripleDES.new(key, 2, IV)
+        elif impl == "openssl" and cryptomath.m2cryptoLoaded:
+            return OpenSSL_TripleDES.new(key, 2, IV)
+        elif impl == "pycrypto" and cryptomath.pycryptoLoaded:
+            return PyCrypto_TripleDES.new(key, 2, IV)
+    raise NotImplementedError()