http://hg.viff.dk/viff/rev/3be465a9f016
changeset: 1077:3be465a9f016
user: Marcel Keller <[email protected]>
date: Mon Jan 12 15:26:47 2009 +0100
summary: AES encryption added.
diffstat:
2 files changed, 55 insertions(+)
viff/aes.py | 42 ++++++++++++++++++++++++++++++++++++++++++
viff/test/test_aes.py | 13 +++++++++++++
diffs (69 lines):
diff -r e77c20718de2 -r 3be465a9f016 viff/aes.py
--- a/viff/aes.py Mon Jan 12 15:23:53 2009 +0100
+++ b/viff/aes.py Mon Jan 12 15:26:47 2009 +0100
@@ -199,3 +199,45 @@
expanded_key.append(new_word)
return expanded_key
+
+ def preprocess(self, input):
+ if (isinstance(input, str)):
+ return [Share(self.runtime, GF256, GF256(ord(c)))
+ for c in input]
+ else:
+ for byte in input:
+ assert byte.field == GF256, \
+ "Input must be a list of GF256 elements " \
+ "or of shares thereof."
+ return input
+
+ def encrypt(self, cleartext, key):
+ """Rijndael encryption.
+
+ Cleartext and key should be either a string or a list of bytes
+ (possibly shared as elements of GF256)."""
+
+ assert len(cleartext) == 4 * self.n_b, "Wrong length of cleartext."
+ assert len(key) == 4 * self.n_k, "Wrong length of key."
+
+ cleartext = self.preprocess(cleartext)
+ key = self.preprocess(key)
+
+ state = [cleartext[i::4] for i in xrange(4)]
+ key = [key[4*i:4*i+4] for i in xrange(self.n_k)]
+
+ expanded_key = self.key_expansion(key)
+
+ self.add_round_key(state, expanded_key[0:self.n_b])
+
+ for i in xrange(1, self.rounds):
+ self.byte_sub(state)
+ self.shift_row(state)
+ self.mix_column(state)
+ self.add_round_key(state, expanded_key[i*self.n_b:(i+1)*self.n_b])
+
+ self.byte_sub(state)
+ self.shift_row(state)
+ self.add_round_key(state, expanded_key[self.rounds*self.n_b:])
+
+ return [byte for word in zip(*state) for byte in word]
diff -r e77c20718de2 -r 3be465a9f016 viff/test/test_aes.py
--- a/viff/test/test_aes.py Mon Jan 12 15:23:53 2009 +0100
+++ b/viff/test/test_aes.py Mon Jan 12 15:26:47 2009 +0100
@@ -116,3 +116,16 @@
word /= 256
self.verify(runtime, result, expected_result)
+
+ @protocol
+ def test_encrypt(self, runtime):
+ cleartext = "Encrypt this!!!!"
+ key = "Supposed to be secret!?!"
+
+ aes = AES(runtime, 192)
+ r = rijndael(key)
+
+ result = aes.encrypt(cleartext, key)
+ expected = [ord(c) for c in r.encrypt(cleartext)]
+
+ return self.verify(runtime, [result], [expected])
_______________________________________________
viff-commits mailing list
[email protected]
http://lists.viff.dk/listinfo.cgi/viff-commits-viff.dk
