diff options
Diffstat (limited to 'passlib/utils/md4.py')
| -rw-r--r-- | passlib/utils/md4.py | 84 |
1 files changed, 42 insertions, 42 deletions
diff --git a/passlib/utils/md4.py b/passlib/utils/md4.py index 63f0d1b..cdc1493 100644 --- a/passlib/utils/md4.py +++ b/passlib/utils/md4.py @@ -7,20 +7,20 @@ implementated based on rfc at http://www.faqs.org/rfcs/rfc1320.html """ -#========================================================================= -#imports -#========================================================================= -#core +#============================================================================= +# imports +#============================================================================= +# core from binascii import hexlify import struct from warnings import warn -#site +# site from passlib.utils.compat import b, bytes, bascii_to_str, irange, PY3 -#local +# local __all__ = [ "md4" ] -#========================================================================= -#utils -#========================================================================= +#============================================================================= +# utils +#============================================================================= def F(x,y,z): return (x&y) | ((~x) & z) @@ -32,9 +32,9 @@ def G(x,y,z): MASK_32 = 2**32-1 -#========================================================================= -#main class -#========================================================================= +#============================================================================= +# main class +#============================================================================= class md4(object): """pep-247 compatible implementation of MD4 hash algorithm @@ -58,16 +58,16 @@ class md4(object): return hexdecimal version of digest """ - #FIXME: make this follow hash object PEP better. - #FIXME: this isn't threadsafe - #XXX: should we monkeypatch ourselves into hashlib for general use? probably wouldn't be nice. + # FIXME: make this follow hash object PEP better. + # FIXME: this isn't threadsafe + # XXX: should we monkeypatch ourselves into hashlib for general use? probably wouldn't be nice. name = "md4" digest_size = digestsize = 16 - _count = 0 #number of 64-byte blocks processed so far (not including _buf) - _state = None #list of [a,b,c,d] 32 bit ints used as internal register - _buf = None #data processed in 64 byte blocks, this holds leftover from last update + _count = 0 # number of 64-byte blocks processed so far (not including _buf) + _state = None # list of [a,b,c,d] 32 bit ints used as internal register + _buf = None # data processed in 64 byte blocks, this holds leftover from last update def __init__(self, content=None): self._count = 0 @@ -76,7 +76,7 @@ class md4(object): if content: self.update(content) - #round 1 table - [abcd k s] + # round 1 table - [abcd k s] _round1 = [ [0,1,2,3, 0,3], [3,0,1,2, 1,7], @@ -99,7 +99,7 @@ class md4(object): [1,2,3,0, 15,19], ] - #round 2 table - [abcd k s] + # round 2 table - [abcd k s] _round2 = [ [0,1,2,3, 0,3], [3,0,1,2, 4,5], @@ -122,7 +122,7 @@ class md4(object): [1,2,3,0, 15,13], ] - #round 3 table - [abcd k s] + # round 3 table - [abcd k s] _round3 = [ [0,1,2,3, 0,3], [3,0,1,2, 8,9], @@ -147,29 +147,29 @@ class md4(object): def _process(self, block): "process 64 byte block" - #unpack block into 16 32-bit ints + # unpack block into 16 32-bit ints X = struct.unpack("<16I", block) - #clone state + # clone state orig = self._state state = list(orig) - #round 1 - F function - (x&y)|(~x & z) + # round 1 - F function - (x&y)|(~x & z) for a,b,c,d,k,s in self._round1: t = (state[a] + F(state[b],state[c],state[d]) + X[k]) & MASK_32 state[a] = ((t<<s) & MASK_32) + (t>>(32-s)) - #round 2 - G function + # round 2 - G function for a,b,c,d,k,s in self._round2: t = (state[a] + G(state[b],state[c],state[d]) + X[k] + 0x5a827999) & MASK_32 state[a] = ((t<<s) & MASK_32) + (t>>(32-s)) - #round 3 - H function - x ^ y ^ z + # round 3 - H function - x ^ y ^ z for a,b,c,d,k,s in self._round3: t = (state[a] + (state[b] ^ state[c] ^ state[d]) + X[k] + 0x6ed9eba1) & MASK_32 state[a] = ((t<<s) & MASK_32) + (t>>(32-s)) - #add back into original state + # add back into original state for i in irange(4): orig[i] = (orig[i]+state[i]) & MASK_32 @@ -199,11 +199,11 @@ class md4(object): return other def digest(self): - #NOTE: backing up state so we can restore it after _process is called, - #in case object is updated again (this is only attr altered by this method) + # NOTE: backing up state so we can restore it after _process is called, + # in case object is updated again (this is only attr altered by this method) orig = list(self._state) - #final block: buf + 0x80, + # final block: buf + 0x80, # then 0x00 padding until congruent w/ 56 mod 64 bytes # then last 8 bytes = msg length in bits buf = self._buf @@ -217,7 +217,7 @@ class md4(object): assert len(block) == 64 self._process(block) - #render digest & restore un-finalized state + # render digest & restore un-finalized state out = struct.pack("<4I", *self._state) self._state = orig return out @@ -225,16 +225,16 @@ class md4(object): def hexdigest(self): return bascii_to_str(hexlify(self.digest())) - #========================================================================= - #eoc - #========================================================================= + #=================================================================== + # eoc + #=================================================================== -#keep ref around for unittest, 'md4' usually replaced by ssl wrapper, below. +# keep ref around for unittest, 'md4' usually replaced by ssl wrapper, below. _builtin_md4 = md4 -#========================================================================= -#check if hashlib provides accelarated md4 -#========================================================================= +#============================================================================= +# check if hashlib provides accelarated md4 +#============================================================================= import hashlib from passlib.utils import PYPY @@ -256,11 +256,11 @@ def _has_native_md4(): # pragma: no cover -- runtime detection return False if _has_native_md4(): - #overwrite md4 class w/ hashlib wrapper + # overwrite md4 class w/ hashlib wrapper def md4(content=None): "wrapper for hashlib.new('md4')" return hashlib.new('md4', content or b('')) -#========================================================================= -#eof -#========================================================================= +#============================================================================= +# eof +#============================================================================= |