[rtags] Allow to 'derive' rtags
Since some releases, rtags (structure underlying uicfg) have selector and may be
copied using something like:
new_rtags = deepcopy(original_rtags)
new_rtags.__module__ = __name__
new_rtags.__select__ = custom_selector
The problem is that starting from that, both rtags wil diverge and changes in
original_rtags won't be considered, while we usually want to set a few specific
rules only in new_rtags. To fix this problem, this cset introduces the notion of
"derivated/parent" rtag, eg:
new_rtags = original_rtags.derive(__name__, custom_selector)
Beside easier copying, when using the above method changes in original_rtags
which are not overriden by new_rtags will be considered since it only hold its
specific rules but look among its parent chain for non-found keys.
Along the way, flake8 unittest_rtags.
Closes #16164880
# 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