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python/gdata/tlslite/utils/AES.py

@@ -0,0 +1,31 @@
+"""Abstract class for AES."""
+
+class AES:
+    def __init__(self, key, mode, IV, implementation):
+        if len(key) not in (16, 24, 32):
+            raise AssertionError()
+        if mode != 2:
+            raise AssertionError()
+        if len(IV) != 16:
+            raise AssertionError()
+        self.isBlockCipher = True
+        self.block_size = 16
+        self.implementation = implementation
+        if len(key)==16:
+            self.name = "aes128"
+        elif len(key)==24:
+            self.name = "aes192"
+        elif len(key)==32:
+            self.name = "aes256"
+        else:
+            raise AssertionError()
+
+    #CBC-Mode encryption, returns ciphertext
+    #WARNING: *MAY* modify the input as well
+    def encrypt(self, plaintext):
+        assert(len(plaintext) % 16 == 0)
+
+    #CBC-Mode decryption, returns plaintext
+    #WARNING: *MAY* modify the input as well
+    def decrypt(self, ciphertext):
+        assert(len(ciphertext) % 16 == 0)