diff options
| -rw-r--r-- | aes_keywrap.py | 32 |
1 files changed, 13 insertions, 19 deletions
diff --git a/aes_keywrap.py b/aes_keywrap.py index 75aaa88..1d0be29 100644 --- a/aes_keywrap.py +++ b/aes_keywrap.py @@ -2,7 +2,7 @@ """ Python prototype of an AES Key Wrap implementation, RFC 5649 flavor -per Russ, using Cryptlib to supply the AES code. +per Russ, using PyCrypto to supply the AES code. """ # Terminology mostly follows the RFC, including variable names. @@ -15,9 +15,9 @@ per Russ, using Cryptlib to supply the AES code. # 64-bit blocks. -from cryptlib_py import * from struct import pack, unpack -import atexit +from Crypto.Cipher import AES +from array import array verbose = False @@ -88,7 +88,7 @@ class Buffer(array): class KEK(object): """ - Key encryption key, based on a Cryptlib encryption context. + Key encryption key, based on a PyCrypto encryption context. This can work with either Block objects or Python arrays. @@ -98,10 +98,7 @@ class KEK(object): """ def __init__(self, key): - self.ctx = cryptCreateContext(CRYPT_UNUSED, CRYPT_ALGO_AES) - atexit.register(cryptDestroyContext, self.ctx) - self.ctx.CTXINFO_MODE = CRYPT_MODE_ECB - self.ctx.CTXINFO_KEY = key + self.ctx = AES.new(key, AES.MODE_ECB) def encrypt_block(self, i1, i2): """ @@ -109,9 +106,9 @@ class KEK(object): with AES-ECB, return the result split back into 64-bit blocks. """ - aes_block = array("B", pack(">QQ", i1, i2)) - cryptEncrypt(self.ctx, aes_block) - o1, o2 = tuple(Block(b) for b in unpack(">QQ", aes_block.tostring())) + aes_block = pack(">QQ", i1, i2) + aes_block = self.ctx.encrypt(aes_block) + o1, o2 = tuple(Block(b) for b in unpack(">QQ", aes_block)) if verbose: print " Encrypt: %s | %s => %s | %s" % tuple(b.to_hex() for b in (i1, i2, o1, o2)) return o1, o2 @@ -123,7 +120,7 @@ class KEK(object): """ aes_block = b1 + b2 - cryptEncrypt(self.ctx, aes_block) + aes_block = self.ctx.encrypt(aes_block.tostring()) return Buffer(aes_block[:8]), Buffer(aes_block[8:]) def decrypt_block(self, i1, i2): @@ -132,9 +129,9 @@ class KEK(object): with AES-ECB, return the result split back into 64-bit blocks. """ - aes_block = array("B", pack(">QQ", i1, i2)) - cryptDecrypt(self.ctx, aes_block) - o1, o2 = tuple(Block(b) for b in unpack(">QQ", aes_block.tostring())) + aes_block = pack(">QQ", i1, i2) + aes_block = self.ctx.decrypt(aes_block) + o1, o2 = tuple(Block(b) for b in unpack(">QQ", aes_block)) if verbose: print " Decrypt: %s | %s => %s | %s" % tuple(b.to_hex() for b in (i1, i2, o1, o2)) return o1, o2 @@ -146,7 +143,7 @@ class KEK(object): """ aes_block = b1 + b2 - cryptDecrypt(self.ctx, aes_block) + aes_block = self.ctx.decrypt(aes_block.tostring()) return Buffer(aes_block[:8]), Buffer(aes_block[8:]) @@ -506,9 +503,6 @@ if __name__ == "__main__": args = parser.parse_args() verbose = args.verbose - cryptInit() - atexit.register(cryptEnd) - if args.under_test in ("long", "both"): print "Testing with Block (Python long) implementation" print |