Implementation of aes-ocb in python and javascript

We can know easily encrypt directories in python,
and generate objects in the alias format.

1 files changed, 28 insertions, 0 deletions

diff --git a/crypto/ocb.py b/crypto/ocb.py
new file mode 100644
index 0000000..08814c7
--- /dev/null
+++ b/crypto/ocb.py
@@ -0,0 +1,28 @@
+#-*- coding: utf-8 -*-
+from aespython import key_expander, aes_cipher, ocb_mode
+import json
+import base64
+def hex2byte(hexstring):
+    return map(ord, hexstring.decode("hex"))
+def byte2hex(byteslist):
+    return str(bytearray(byteslist)).encode("hex")
+
+if __name__=="__main__":
+    KE = key_expander.KeyExpander(128)
+    key = hex2byte('12538243c49f1c58e6f7b0687bbd65b2')
+    expanded_key = KE.expand(key)
+    aes_cipher_128 = aes_cipher.AESCipher(expanded_key)
+    aes_ocb_128 = ocb_mode.OCBMode(aes_cipher_128, 16)
+    iv = hex2byte('250c3041c00a605a4100e264abbc588b')
+    aes_ocb_128.set_iv(iv)
+    plaintext = "La chaire est triste, hélas ! et j'ai lu tous les livres.".encode("hex")
+    header = "".encode("hex")
+    (tag,ciphertext) = aes_ocb_128.encrypt_block(hex2byte(plaintext), hex2byte(header))
+    sjcl_object = {"iv": base64.b64encode(bytearray(iv)).rstrip("="),
+                 "mode": "ocb2",
+                 "tag": 128,
+                 "ct": base64.b64encode(bytearray(ciphertext) +
+                                        bytearray(tag)).rstrip("=")
+                 }
+    print json.dumps(sjcl_object)
+