freeipa/ipalib/aci.py

246 lines
8.7 KiB
Python
Executable File

# Authors:
# Rob Crittenden <rcritten@redhat.com>
#
# Copyright (C) 2008 Red Hat
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; version 2 only
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
import shlex
import re
import ldap
# The Python re module doesn't do nested parenthesis
# Break the ACI into 3 pieces: target, name, permissions/bind_rules
ACIPat = re.compile(r'\s*(\(.*\)+)\s*\(version\s+3.0\s*;\s*acl\s+\"(.*)\"\s*;\s*(.*);\)')
# Break the permissions/bind_rules out
PermPat = re.compile(r'(\w+)\s*\((.*)\)\s+(.*)')
class ACI:
"""
Holds the basic data for an ACI entry, as stored in the cn=accounts
entry in LDAP. Has methods to parse an ACI string and export to an
ACI String.
"""
# Don't allow arbitrary attributes to be set in our __setattr__ implementation.
_objectattrs = ["name", "orig_acistr", "target", "action", "permissions",
"bindrule"]
__actions = ["allow", "deny"]
__permissions = ["read", "write", "add", "delete", "search", "compare",
"selfwrite", "proxy", "all"]
def __init__(self,acistr=None):
self.name = None
self.orig_acistr = acistr
self.target = {}
self.action = "allow"
self.permissions = ["write"]
self.bindrule = None
if acistr is not None:
self._parse_acistr(acistr)
def __getitem__(self,key):
"""Fake getting attributes by key for sorting"""
if key == 0:
return self.name
if key == 1:
return self.source_group
if key == 2:
return self.dest_group
raise TypeError("Unknown key value %s" % key)
def __repr__(self):
"""An alias for export_to_string()"""
return self.export_to_string()
def __getattr__(self, name):
"""
Backward compatibility for the old ACI class.
The following extra attributes are available:
- source_group
- dest_group
- attrs
"""
if name == 'source_group':
group = ''
dn = self.bindrule.split('=',1)
if dn[0] == "groupdn":
group = self._remove_quotes(dn[1])
if group.startswith("ldap:///"):
group = group[8:]
return group
if name == 'dest_group':
group = self.target.get('targetfilter', '')
if group:
g = group.split('=',1)[1]
if g.endswith(')'):
g = g[:-1]
return g
return ''
if name == 'attrs':
return self.target.get('targetattr', None)
raise AttributeError, "object has no attribute '%s'" % name
def __setattr__(self, name, value):
"""
Backward compatibility for the old ACI class.
The following extra attributes are available:
- source_group
- dest_group
- attrs
"""
if name == 'source_group':
self.__dict__['bindrule'] = 'groupdn="ldap:///%s"' % value
elif name == 'dest_group':
if value.startswith('('):
self.__dict__['target']['targetfilter'] = 'memberOf=%s' % value
else:
self.__dict__['target']['targetfilter'] = '(memberOf=%s)' % value
elif name == 'attrs':
self.__dict__['target']['targetattr'] = value
elif name in self._objectattrs:
self.__dict__[name] = value
else:
raise AttributeError, "object has no attribute '%s'" % name
def export_to_string(self):
"""Output a Directory Server-compatible ACI string"""
self.validate()
aci = ""
for t in self.target:
if isinstance(self.target[t], list):
target = ""
for l in self.target[t]:
target = target + l + " || "
target = target[:-4]
aci = aci + "(%s=\"%s\")" % (t, target)
else:
aci = aci + "(%s=\"%s\")" % (t, self.target[t])
aci = aci + "(version 3.0;acl \"%s\";%s (%s) %s" % (self.name, self.action, ",".join(self.permissions), self.bindrule) + ";)"
return aci
def _remove_quotes(self, s):
# Remove leading and trailing quotes
if s.startswith('"'):
s = s[1:]
if s.endswith('"'):
s = s[:-1]
return s
def _parse_target(self, aci):
lexer = shlex.shlex(aci)
lexer.wordchars = lexer.wordchars + "."
l = []
var = False
for token in lexer:
# We should have the form (a = b)(a = b)...
if token == "(":
var = lexer.next().strip()
operator = lexer.next()
if operator != "=" and operator != "!=":
raise SyntaxError('No operator in target, got %s' % operator)
val = lexer.next().strip()
val = self._remove_quotes(val)
end = lexer.next()
if end != ")":
raise SyntaxError('No end parenthesis in target, got %s' % end)
if var == 'targetattr':
# Make a string of the form attr || attr || ... into a list
t = re.split('[\W]+', val)
self.target[var] = t
else:
self.target[var] = val
def _parse_acistr(self, acistr):
acimatch = ACIPat.match(acistr)
if not acimatch or len(acimatch.groups()) < 3:
raise SyntaxError, "malformed ACI"
self._parse_target(acimatch.group(1))
self.name = acimatch.group(2)
bindperms = PermPat.match(acimatch.group(3))
if not bindperms or len(bindperms.groups()) < 3:
raise SyntaxError, "malformed ACI"
self.action = bindperms.group(1)
self.permissions = bindperms.group(2).split(',')
self.bindrule = bindperms.group(3)
def validate(self):
"""Do some basic verification that this will produce a
valid LDAP ACI.
returns True if valid
"""
if not isinstance(self.permissions, list):
raise SyntaxError, "permissions must be a list"
for p in self.permissions:
if not p.lower() in self.__permissions:
raise SyntaxError, "invalid permission: '%s'" % p
if not self.name:
raise SyntaxError, "name must be set"
if not isinstance(self.name, basestring):
raise SyntaxError, "name must be a string"
if not isinstance(self.target, dict) or len(self.target) == 0:
raise SyntaxError, "target must be a non-empty dictionary"
return True
def extract_group_cns(aci_list, client):
"""Extracts all the cn's from a list of aci's and returns them as a hash
from group_dn to group_cn.
It first tries to cheat by looking at the first rdn for the
group dn. If that's not cn for some reason, it looks up the group."""
group_dn_to_cn = {}
for aci in aci_list:
for dn in (aci.source_group, aci.dest_group):
if not group_dn_to_cn.has_key(dn):
rdn_list = ldap.explode_dn(dn, 0)
first_rdn = rdn_list[0]
(type,value) = first_rdn.split('=')
if type == "cn":
group_dn_to_cn[dn] = value
else:
try:
group = client.get_entry_by_dn(dn, ['cn'])
group_dn_to_cn[dn] = group.getValue('cn')
except ipaerror.IPAError, e:
group_dn_to_cn[dn] = 'unknown'
return group_dn_to_cn
if __name__ == '__main__':
# Pass in an ACI as a string
a = ACI('(targetattr="title")(targetfilter="(memberOf=cn=bar,cn=groups,cn=accounts ,dc=example,dc=com)")(version 3.0;acl "foobar";allow (write) groupdn="ldap:///cn=foo,cn=groups,cn=accounts,dc=example,dc=com";)')
print a
# Create an ACI in pieces
a = ACI()
a.name ="foobar"
a.source_group="cn=foo,cn=groups,dc=example,dc=org"
a.dest_group="cn=bar,cn=groups,dc=example,dc=org"
a.attrs = ['title']
a.permissions = ['read','write','add']
print a