mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-12-09 18:48:05 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 11

[Part of patch #1182394] Move the HMAC blocksize to be a class-level

Browse source 
constant; this allows changing it in a subclass.  To accommodate this,
copy() now uses __class__.  Also add some text to a comment.
This commit is contained in:
Andrew M. Kuchling 2006-12-27 03:25:31 +00:00
parent a4b2381b20
commit a7ebb33975
1 changed files with 4 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

7
Lib/hmac.py
View file

@ -7,7 +7,7 @@ trans_5C = "".join ([chr (x ^ 0x5C) for x in xrange(256)])
trans_36 = "".join ([chr (x ^ 0x36) for x in xrange(256)]) trans_36 = "".join ([chr (x ^ 0x36) for x in xrange(256)])
# The size of the digests returned by HMAC depends on the underlying # The size of the digests returned by HMAC depends on the underlying
# hashing module used. # hashing module used. Use digest_size from the instance of HMAC instead.
digest_size = None digest_size = None
# A unique object passed by HMAC.copy() to the HMAC constructor, in order # A unique object passed by HMAC.copy() to the HMAC constructor, in order
@ -20,6 +20,7 @@ class HMAC:
This supports the API for Cryptographic Hash Functions (PEP 247). This supports the API for Cryptographic Hash Functions (PEP 247).
""" """
blocksize = 64 # 512-bit HMAC; can be changed in subclasses.
def __init__(self, key, msg = None, digestmod = None): def __init__(self, key, msg = None, digestmod = None):
"""Create a new HMAC object. """Create a new HMAC object.
@ -47,7 +48,7 @@ class HMAC:
self.inner = self.digest_cons() self.inner = self.digest_cons()
self.digest_size = self.inner.digest_size self.digest_size = self.inner.digest_size
blocksize = 64 blocksize = self.blocksize
if len(key) > blocksize: if len(key) > blocksize:
key = self.digest_cons(key).digest() key = self.digest_cons(key).digest()
@ -70,7 +71,7 @@ class HMAC:
An update to this copy won't affect the original object. An update to this copy won't affect the original object.
""" """
other = HMAC(_secret_backdoor_key) other = self.__class__(_secret_backdoor_key)
other.digest_cons = self.digest_cons other.digest_cons = self.digest_cons
other.digest_size = self.digest_size other.digest_size = self.digest_size
other.inner = self.inner.copy() other.inner = self.inner.copy()