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python/gdata/tlslite/utils/TripleDES.py

@@ -0,0 +1,26 @@
+"""Abstract class for 3DES."""
+
+from compat import * #For True
+
+class TripleDES:
+    def __init__(self, key, mode, IV, implementation):
+        if len(key) != 24:
+            raise ValueError()
+        if mode != 2:
+            raise ValueError()
+        if len(IV) != 8:
+            raise ValueError()
+        self.isBlockCipher = True
+        self.block_size = 8
+        self.implementation = implementation
+        self.name = "3des"
+
+    #CBC-Mode encryption, returns ciphertext
+    #WARNING: *MAY* modify the input as well
+    def encrypt(self, plaintext):
+        assert(len(plaintext) % 8 == 0)
+
+    #CBC-Mode decryption, returns plaintext
+    #WARNING: *MAY* modify the input as well
+    def decrypt(self, ciphertext):
+        assert(len(ciphertext) % 8 == 0)