diff options
Diffstat (limited to 'passlib/handlers/sun_md5_crypt.py')
| -rw-r--r-- | passlib/handlers/sun_md5_crypt.py | 169 |
1 files changed, 88 insertions, 81 deletions
diff --git a/passlib/handlers/sun_md5_crypt.py b/passlib/handlers/sun_md5_crypt.py index 8296e5e..a99289c 100644 --- a/passlib/handlers/sun_md5_crypt.py +++ b/passlib/handlers/sun_md5_crypt.py @@ -7,30 +7,29 @@ See documentation for details. """ -#========================================================= -#imports -#========================================================= -#core +#============================================================================= +# imports +#============================================================================= +# core from hashlib import md5 import re import logging; log = logging.getLogger(__name__) from warnings import warn -#site -#libs +# site +# pkg from passlib.utils import h64, to_unicode from passlib.utils.compat import b, bytes, byte_elem_value, irange, u, \ uascii_to_str, unicode, str_to_bascii import passlib.utils.handlers as uh -#pkg -#local +# local __all__ = [ "sun_md5_crypt", ] -#========================================================= -#backend -#========================================================= -#constant data used by alg - Hamlet act 3 scene 1 + null char +#============================================================================= +# backend +#============================================================================= +# constant data used by alg - Hamlet act 3 scene 1 + null char # exact bytes as in http://www.ibiblio.org/pub/docs/books/gutenberg/etext98/2ws2610.txt # from Project Gutenberg. @@ -72,13 +71,13 @@ MAGIC_HAMLET = b( "Be all my sins remember'd.\n\x00" #<- apparently null at end of C string is included (test vector won't pass otherwise) ) -#NOTE: these sequences are pre-calculated iteration ranges used by X & Y loops w/in rounds function below +# NOTE: these sequences are pre-calculated iteration ranges used by X & Y loops w/in rounds function below xr = irange(7) _XY_ROUNDS = [ - tuple((i,i,i+3) for i in xr), #xrounds 0 - tuple((i,i+1,i+4) for i in xr), #xrounds 1 - tuple((i,i+8,(i+11)&15) for i in xr), #yrounds 0 - tuple((i,(i+9)&15, (i+12)&15) for i in xr), #yrounds 1 + tuple((i,i,i+3) for i in xr), # xrounds 0 + tuple((i,i+1,i+4) for i in xr), # xrounds 1 + tuple((i,i+8,(i+11)&15) for i in xr), # yrounds 0 + tuple((i,(i+9)&15, (i+12)&15) for i in xr), # yrounds 1 ] del xr @@ -88,37 +87,45 @@ def raw_sun_md5_crypt(secret, rounds, salt): assert isinstance(secret, bytes) assert isinstance(salt, bytes) - #validate rounds + # validate rounds if rounds <= 0: rounds = 0 real_rounds = 4096 + rounds - #NOTE: spec seems to imply max 'rounds' is 2**32-1 + # NOTE: spec seems to imply max 'rounds' is 2**32-1 - #generate initial digest to start off round 0. - #NOTE: algorithm 'salt' includes full config string w/ trailing "$" + # generate initial digest to start off round 0. + # NOTE: algorithm 'salt' includes full config string w/ trailing "$" result = md5(secret + salt).digest() assert len(result) == 16 - #NOTE: many things have been inlined to speed up the loop as much as possible, - # so that this only barely resembles the algorithm as described in the docs. - # * all accesses to a given bit have been inlined using the formula - # rbitval(bit) = (rval((bit>>3) & 15) >> (bit & 7)) & 1 - # * the calculation of coinflip value R has been inlined - # * the conditional division of coinflip value V has been inlined as a shift right of 0 or 1. - # * the i, i+3, etc iterations are precalculated in lists. - # * the round-based conditional division of x & y is now performed - # by choosing an appropriate precalculated list, so only the 7 used bits - # are actually calculated + # NOTE: many things in this function have been inlined (to speed up the loop + # as much as possible), to the point that this code barely resembles + # the algorithm as described in the docs. in particular: + # + # * all accesses to a given bit have been inlined using the formula + # rbitval(bit) = (rval((bit>>3) & 15) >> (bit & 7)) & 1 + # + # * the calculation of coinflip value R has been inlined + # + # * the conditional division of coinflip value V has been inlined as + # a shift right of 0 or 1. + # + # * the i, i+3, etc iterations are precalculated in lists. + # + # * the round-based conditional division of x & y is now performed + # by choosing an appropriate precalculated list, so that it only + # calculates the 7 bits which will actually be used. + # X_ROUNDS_0, X_ROUNDS_1, Y_ROUNDS_0, Y_ROUNDS_1 = _XY_ROUNDS - #NOTE: % appears to be *slightly* slower than &, so we prefer & if possible + # NOTE: % appears to be *slightly* slower than &, so we prefer & if possible round = 0 while round < real_rounds: - #convert last result byte string to list of byte-ints for easy access + # convert last result byte string to list of byte-ints for easy access rval = [ byte_elem_value(c) for c in result ].__getitem__ - #build up X bit by bit + # build up X bit by bit x = 0 xrounds = X_ROUNDS_1 if (rval((round>>3) & 15)>>(round & 7)) & 1 else X_ROUNDS_0 for i, ia, ib in xrounds: @@ -127,7 +134,7 @@ def raw_sun_md5_crypt(secret, rounds, salt): v = rval((a >> (b % 5)) & 15) >> ((b>>(a&7)) & 1) x |= ((rval((v>>3)&15)>>(v&7))&1) << i - #build up Y bit by bit + # build up Y bit by bit y = 0 yrounds = Y_ROUNDS_1 if (rval(((round+64)>>3) & 15)>>(round & 7)) & 1 else Y_ROUNDS_0 for i, ia, ib in yrounds: @@ -136,10 +143,10 @@ def raw_sun_md5_crypt(secret, rounds, salt): v = rval((a >> (b % 5)) & 15) >> ((b>>(a&7)) & 1) y |= ((rval((v>>3)&15)>>(v&7))&1) << i - #extract x'th and y'th bit, xoring them together to yeild "coin flip" + # extract x'th and y'th bit, xoring them together to yeild "coin flip" coin = ((rval(x>>3) >> (x&7)) ^ (rval(y>>3) >> (y&7))) & 1 - #construct hash for this round + # construct hash for this round h = md5(result) if coin: h.update(MAGIC_HAMLET) @@ -148,10 +155,10 @@ def raw_sun_md5_crypt(secret, rounds, salt): round += 1 - #encode output + # encode output return h64.encode_transposed_bytes(result, _chk_offsets) -#NOTE: same offsets as md5_crypt +# NOTE: same offsets as md5_crypt _chk_offsets = ( 12,6,0, 13,7,1, @@ -161,9 +168,9 @@ _chk_offsets = ( 11, ) -#========================================================= -#handler -#========================================================= +#============================================================================= +# handler +#============================================================================= class sun_md5_crypt(uh.HasRounds, uh.HasSalt, uh.GenericHandler): """This class implements the Sun-MD5-Crypt password hash, and follows the :ref:`password-hash-api`. @@ -206,47 +213,47 @@ class sun_md5_crypt(uh.HasRounds, uh.HasSalt, uh.GenericHandler): .. versionadded:: 1.6 """ - #========================================================= - #class attrs - #========================================================= + #=================================================================== + # class attrs + #=================================================================== name = "sun_md5_crypt" setting_kwds = ("salt", "rounds", "bare_salt", "salt_size") checksum_chars = uh.HASH64_CHARS checksum_size = 22 - #NOTE: docs say max password length is 255. - #release 9u2 + # NOTE: docs say max password length is 255. + # release 9u2 - #NOTE: not sure if original crypt has a salt size limit, + # NOTE: not sure if original crypt has a salt size limit, # all instances that have been seen use 8 chars. default_salt_size = 8 min_salt_size = 0 max_salt_size = None salt_chars = uh.HASH64_CHARS - default_rounds = 5000 #current passlib default + default_rounds = 5000 # current passlib default min_rounds = 0 max_rounds = 4294963199 ##2**32-1-4096 - #XXX: ^ not sure what it does if past this bound... does 32 int roll over? + # XXX: ^ not sure what it does if past this bound... does 32 int roll over? rounds_cost = "linear" ident_values = (u("$md5$"), u("$md5,")) - #========================================================= - #instance attrs - #========================================================= - bare_salt = False #flag to indicate legacy hashes that lack "$$" suffix + #=================================================================== + # instance attrs + #=================================================================== + bare_salt = False # flag to indicate legacy hashes that lack "$$" suffix - #========================================================= - #constructor - #========================================================= + #=================================================================== + # constructor + #=================================================================== def __init__(self, bare_salt=False, **kwds): self.bare_salt = bare_salt super(sun_md5_crypt, self).__init__(**kwds) - #========================================================= - #internal helpers - #========================================================= + #=================================================================== + # internal helpers + #=================================================================== @classmethod def identify(cls, hash): hash = uh.to_unicode_for_identify(hash) @@ -257,9 +264,9 @@ class sun_md5_crypt(uh.HasRounds, uh.HasSalt, uh.GenericHandler): hash = to_unicode(hash, "ascii", "hash") # - #detect if hash specifies rounds value. - #if so, parse and validate it. - #by end, set 'rounds' to int value, and 'tail' containing salt+chk + # detect if hash specifies rounds value. + # if so, parse and validate it. + # by end, set 'rounds' to int value, and 'tail' containing salt+chk # if hash.startswith(u("$md5$")): rounds = 0 @@ -276,7 +283,7 @@ class sun_md5_crypt(uh.HasRounds, uh.HasSalt, uh.GenericHandler): if rstr != unicode(rounds): raise uh.exc.ZeroPaddedRoundsError(cls) if rounds == 0: - #NOTE: not sure if this is forbidden by spec or not; + # NOTE: not sure if this is forbidden by spec or not; # but allowing it would complicate things, # and it should never occur anyways. raise uh.exc.MalformedHashError(cls, "explicit zero rounds") @@ -285,9 +292,9 @@ class sun_md5_crypt(uh.HasRounds, uh.HasSalt, uh.GenericHandler): raise uh.exc.InvalidHashError(cls) # - #salt/checksum separation is kinda weird, - #to deal cleanly with some backward-compatible workarounds - #implemented by original implementation. + # salt/checksum separation is kinda weird, + # to deal cleanly with some backward-compatible workarounds + # implemented by original implementation. # chk_idx = hash.rfind(u("$"), salt_idx) if chk_idx == -1: @@ -333,25 +340,25 @@ class sun_md5_crypt(uh.HasRounds, uh.HasSalt, uh.GenericHandler): hash = u("%s$%s") % (hash, chk) return uascii_to_str(hash) - #========================================================= - #primary interface - #========================================================= - #TODO: if we're on solaris, check for native crypt() support. - # this will require extra testing, to make sure native crypt - # actually behaves correctly. - # especially, when using ''-config, make sure to append '$x' to string. + #=================================================================== + # primary interface + #=================================================================== + # TODO: if we're on solaris, check for native crypt() support. + # this will require extra testing, to make sure native crypt + # actually behaves correctly. of particular importance: + # when using ""-config, make sure to append "$x" to string. def _calc_checksum(self, secret): - #NOTE: no reference for how sun_md5_crypt handles unicode + # NOTE: no reference for how sun_md5_crypt handles unicode if isinstance(secret, unicode): secret = secret.encode("utf-8") config = str_to_bascii(self.to_string(withchk=False)) return raw_sun_md5_crypt(secret, self.rounds, config).decode("ascii") - #========================================================= - #eoc - #========================================================= + #=================================================================== + # eoc + #=================================================================== -#========================================================= -#eof -#========================================================= +#============================================================================= +# eof +#============================================================================= |