Merge pull request #697 from Atheros1/master

support pyelliptic's updated HMAC algorithm
This commit is contained in:
Jonathan Warren 2014-07-29 13:56:29 -04:00
commit 833131f2c9

View File

@ -437,8 +437,10 @@ class ECC:
iv = OpenSSL.rand(OpenSSL.get_cipher(ciphername).get_blocksize())
ctx = Cipher(key_e, iv, 1, ciphername)
ciphertext = ctx.ciphering(data)
#ciphertext = iv + pubkey + ctx.ciphering(data) # We will switch to this line after an upgrade period
mac = hmac_sha256(key_m, ciphertext)
return iv + pubkey + ciphertext + mac
#return ciphertext + mac # We will switch to this line after an upgrade period.
def decrypt(self, data, ciphername='aes-256-cbc'):
"""
@ -454,7 +456,14 @@ class ECC:
mac = data[i:]
key = sha512(self.raw_get_ecdh_key(pubkey_x, pubkey_y)).digest()
key_e, key_m = key[:32], key[32:]
"""
pyelliptic was changed slightly so that the hmac covers the
iv and pubkey. So let's have an upgrade period where we support
both the old and the new hmac'ing algorithms.
https://github.com/yann2192/pyelliptic/issues/17
"""
if hmac_sha256(key_m, ciphertext) != mac:
raise RuntimeError("Fail to verify data")
if hmac_sha256(key_m, data[:len(data) - 32]) != mac:
raise RuntimeError("Fail to verify data")
ctx = Cipher(key_e, iv, 0, ciphername)
return ctx.ciphering(ciphertext)