initial code for dumping imessages in a reasonable format

dump-imessages/iphone-dataprotection/python_scripts/crypto/aes.py

@@ -0,0 +1,26 @@
+from Crypto.Cipher import AES
+
+ZEROIV = "\x00"*16
+def removePadding(blocksize, s):
+    'Remove rfc 1423 padding from string.'
+    n = ord(s[-1]) # last byte contains number of padding bytes
+    if n > blocksize or n > len(s):
+        raise Exception('invalid padding')
+    return s[:-n]
+
+
+def AESdecryptCBC(data, key, iv=ZEROIV, padding=False):
+    if len(data) % 16:
+        print "AESdecryptCBC: data length not /16, truncating"
+        data = data[0:(len(data)/16) * 16]
+    data = AES.new(key, AES.MODE_CBC, iv).decrypt(data)
+    if padding:
+        return removePadding(16, data)
+    return data
+
+def AESencryptCBC(data, key, iv=ZEROIV, padding=False):
+    if len(data) % 16:
+        print "AESdecryptCBC: data length not /16, truncating"
+        data = data[0:(len(data)/16) * 16]
+    data = AES.new(key, AES.MODE_CBC, iv).encrypt(data)
+    return data