md5crypt.py
author Rémi Cardona <remi.cardona@logilab.fr>
Thu, 10 Dec 2015 12:34:15 +0100
changeset 10960 9e64fddebc89
parent 10775 4b3c1069bd4e
permissions -rw-r--r--
merge with 3.21.3 The change in unittest_serverctl.py is needed because of daef7ce08fea (from 3.20.11) and 3914388b2d0f (from the 3.22 branch). Due to both changes, CubicWebTC.config.repository no longer creates a new repository (and thus, a new connection). Since both DBDumpCommand and CubicWebTC.tearDown try to shutdown the repo, tearDown breaks apart. The solution is to temporarily disable ServerConfiguration's config cache. By forcing DBDumpCommand to get a new configuration object, it then gets its own Repo object, allowing tearDown and DBDumpCommand to work independently.

# md5crypt.py
#
# 0423.2000 by michal wallace http://www.sabren.com/
# based on perl's Crypt::PasswdMD5 by Luis Munoz (lem@cantv.net)
# based on /usr/src/libcrypt/crypt.c from FreeBSD 2.2.5-RELEASE
#
# MANY THANKS TO
#
#  Carey Evans - http://home.clear.net.nz/pages/c.evans/
#  Dennis Marti - http://users.starpower.net/marti1/
#
#  For the patches that got this thing working!
#
# modification by logilab:
# * remove usage of the string module
# * don't include the magic string in the output string
#   for true crypt.crypt compatibility
# * use hashlib module instead of md5
#########################################################
"""md5crypt.py - Provides interoperable MD5-based crypt() function

SYNOPSIS

        import md5crypt.py

        cryptedpassword = md5crypt.md5crypt(password, salt);

DESCRIPTION

unix_md5_crypt() provides a crypt()-compatible interface to the
rather new MD5-based crypt() function found in modern operating systems.
It's based on the implementation found on FreeBSD 2.2.[56]-RELEASE and
contains the following license in it:

 "THE BEER-WARE LICENSE" (Revision 42):
 <phk@login.dknet.dk> wrote this file.  As long as you retain this notice you
 can do whatever you want with this stuff. If we meet some day, and you think
 this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
"""

MAGIC = b'$1$'                        # Magic string
ITOA64 = b"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"

from hashlib import md5 # pylint: disable=E0611

from six import text_type, indexbytes
from six.moves import range


def to64 (v, n):
    ret = bytearray()
    while (n - 1 >= 0):
        n = n - 1
        ret.append(ITOA64[v & 0x3f])
        v = v >> 6
    return ret

def crypt(pw, salt):
    if isinstance(pw, text_type):
        pw = pw.encode('utf-8')
    if isinstance(salt, text_type):
        salt = salt.encode('ascii')
    # Take care of the magic string if present
    if salt.startswith(MAGIC):
        salt = salt[len(MAGIC):]
    # salt can have up to 8 characters:
    salt = salt.split(b'$', 1)[0]
    salt = salt[:8]
    ctx = pw + MAGIC + salt
    final = md5(pw + salt + pw).digest()
    for pl in range(len(pw), 0, -16):
        if pl > 16:
            ctx = ctx + final[:16]
        else:
            ctx = ctx + final[:pl]
    # Now the 'weird' xform (??)
    i = len(pw)
    while i:
        if i & 1:
            ctx = ctx + b'\0'  #if ($i & 1) { $ctx->add(pack("C", 0)); }
        else:
            ctx = ctx + pw[0]
        i = i >> 1
    final = md5(ctx).digest()
    # The following is supposed to make
    # things run slower.
    # my question: WTF???
    for i in range(1000):
        ctx1 = b''
        if i & 1:
            ctx1 = ctx1 + pw
        else:
            ctx1 = ctx1 + final[:16]
        if i % 3:
            ctx1 = ctx1 + salt
        if i % 7:
            ctx1 = ctx1 + pw
        if i & 1:
            ctx1 = ctx1 + final[:16]
        else:
            ctx1 = ctx1 + pw
        final = md5(ctx1).digest()
    # Final xform
    passwd = b''
    passwd += to64((indexbytes(final, 0) << 16)
                   |(indexbytes(final, 6) << 8)
                   |(indexbytes(final, 12)),4)
    passwd += to64((indexbytes(final, 1) << 16)
                   |(indexbytes(final, 7) << 8)
                   |(indexbytes(final, 13)), 4)
    passwd += to64((indexbytes(final, 2) << 16)
                   |(indexbytes(final, 8) << 8)
                   |(indexbytes(final, 14)), 4)
    passwd += to64((indexbytes(final, 3) << 16)
                   |(indexbytes(final, 9) << 8)
                   |(indexbytes(final, 15)), 4)
    passwd += to64((indexbytes(final, 4) << 16)
                   |(indexbytes(final, 10) << 8)
                   |(indexbytes(final, 5)), 4)
    passwd += to64((indexbytes(final, 11)), 2)
    return passwd