# Unix SMB/CIFS implementation.
# Copyright (C) Matthieu Patou <mat@matws.net> 2009-2010
#
#
# 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; either version 3 of the License, or
# (at your option) any later version.
#
# 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, see <http://www.gnu.org/licenses/>.
#
"""NT Acls."""
import os
import samba.xattr_native, samba.xattr_tdb, samba.posix_eadb
from samba.dcerpc import security, xattr, idmap
from samba.ndr import ndr_pack, ndr_unpack
from samba.samba3 import smbd
class XattrBackendError(Exception):
"""A generic xattr backend error."""
def checkset_backend(lp, backend, eadbfile):
'''return the path to the eadb, or None'''
if backend is None:
xattr_tdb = lp.get("xattr_tdb:file")
if xattr_tdb is not None:
return (samba.xattr_tdb, lp.get("xattr_tdb:file"))
posix_eadb = lp.get("posix:eadb")
if posix_eadb is not None:
return (samba.posix_eadb, lp.get("posix:eadb"))
return (None, None)
elif backend == "native":
return (None, None)
elif backend == "eadb":
if eadbfile is not None:
return (samba.posix_eadb, eadbfile)
else:
return (samba.posix_eadb, os.path.abspath(os.path.join(lp.get("private dir"), "eadb.tdb")))
elif backend == "tdb":
if eadbfile is not None:
return (samba.xattr_tdb, eadbfile)
else:
return (samba.xattr_tdb, os.path.abspath(os.path.join(lp.get("state dir"), "xattr.tdb")))
else:
raise XattrBackendError("Invalid xattr backend choice %s"%backend)
def getntacl(lp, file, backend=None, eadbfile=None, direct_db_access=True):
if direct_db_access:
(backend_obj, dbname) = checkset_backend(lp, backend, eadbfile)
if dbname is not None:
try:
attribute = backend_obj.wrap_getxattr(dbname, file,
xattr.XATTR_NTACL_NAME)
except Exception:
# FIXME: Don't catch all exceptions, just those related to opening
# xattrdb
print "Fail to open %s" % dbname
attribute = samba.xattr_native.wrap_getxattr(file,
xattr.XATTR_NTACL_NAME)
else:
attribute = samba.xattr_native.wrap_getxattr(file,
xattr.XATTR_NTACL_NAME)
ntacl = ndr_unpack(xattr.NTACL, attribute)
if ntacl.version == 1:
return ntacl.info
elif ntacl.version == 2:
return ntacl.info.sd
elif ntacl.version == 3:
return ntacl.info.sd
else:
return smbd.get_nt_acl(file, security.SECINFO_OWNER | security.SECINFO_GROUP | security.SECINFO_DACL | security.SECINFO_SACL)
def setntacl(lp, file, sddl, domsid, backend=None, eadbfile=None, use_ntvfs=True, skip_invalid_chown=False, passdb=None):
sid = security.dom_sid(domsid)
sd = security.descriptor.from_sddl(sddl, sid)
if not use_ntvfs and skip_invalid_chown:
# Check if the owner can be resolved as a UID
(owner_id, owner_type) = passdb.sid_to_id(sd.owner_sid)
if ((owner_type != idmap.ID_TYPE_UID) and (owner_type != idmap.ID_TYPE_BOTH)):
# Check if this particular owner SID was domain admins,
# because we special-case this as mapping to
# 'administrator' instead.
if sd.owner_sid == security.dom_sid("%s-%d" % (domsid, security.DOMAIN_RID_ADMINS)):
administrator = security.dom_sid("%s-%d" % (domsid, security.DOMAIN_RID_ADMINISTRATOR))
(admin_id, admin_type) = passdb.sid_to_id(administrator)
# Confirm we have a UID for administrator
if ((admin_type == idmap.ID_TYPE_UID) or (admin_type == idmap.ID_TYPE_BOTH)):
# Set it, changing the owner to 'administrator' rather than domain admins
sd2 = security.descriptor.from_sddl(sddl, sid)
sd2.owner_sid = administrator
smbd.set_nt_acl(file, security.SECINFO_OWNER |security.SECINFO_GROUP | security.SECINFO_DACL | security.SECINFO_SACL, sd2)
# and then set an NTVFS ACL (which does not set the posix ACL) to pretend the owner really was set
use_ntvfs = True
else:
raise XattrBackendError("Unable to find UID for domain administrator %s, got id %d of type %d" % (administrator, admin_id, admin_type))
else:
# For all other owning users, reset the owner to root
# and then set the ACL without changing the owner
#
# This won't work in test environments, as it tries a real (rather than xattr-based fake) chown
os.chown(file, 0, 0)
smbd.set_nt_acl(file, security.SECINFO_GROUP | security.SECINFO_DACL | security.SECINFO_SACL, sd)
if use_ntvfs:
(backend_obj, dbname) = checkset_backend(lp, backend, eadbfile)
ntacl = xattr.NTACL()
ntacl.version = 1
ntacl.info = sd
if dbname is not None:
try:
backend_obj.wrap_setxattr(dbname,
file, xattr.XATTR_NTACL_NAME, ndr_pack(ntacl))
except Exception:
# FIXME: Don't catch all exceptions, just those related to opening
# xattrdb
print "Fail to open %s" % dbname
samba.xattr_native.wrap_setxattr(file, xattr.XATTR_NTACL_NAME,
ndr_pack(ntacl))
else:
samba.xattr_native.wrap_setxattr(file, xattr.XATTR_NTACL_NAME,
ndr_pack(ntacl))
else:
smbd.set_nt_acl(file, security.SECINFO_OWNER | security.SECINFO_GROUP | security.SECINFO_DACL | security.SECINFO_SACL, sd)
def ldapmask2filemask(ldm):
"""Takes the access mask of a DS ACE and transform them in a File ACE mask.
"""
RIGHT_DS_CREATE_CHILD = 0x00000001
RIGHT_DS_DELETE_CHILD = 0x00000002
RIGHT_DS_LIST_CONTENTS = 0x00000004
ACTRL_DS_SELF = 0x00000008
RIGHT_DS_READ_PROPERTY = 0x00000010
RIGHT_DS_WRITE_PROPERTY = 0x00000020
RIGHT_DS_DELETE_TREE = 0x00000040
RIGHT_DS_LIST_OBJECT = 0x00000080
RIGHT_DS_CONTROL_ACCESS = 0x00000100
FILE_READ_DATA = 0x0001
FILE_LIST_DIRECTORY = 0x0001
FILE_WRITE_DATA = 0x0002
FILE_ADD_FILE = 0x0002
FILE_APPEND_DATA = 0x0004
FILE_ADD_SUBDIRECTORY = 0x0004
FILE_CREATE_PIPE_INSTANCE = 0x0004
FILE_READ_EA = 0x0008
FILE_WRITE_EA = 0x0010
FILE_EXECUTE = 0x0020
FILE_TRAVERSE = 0x0020
FILE_DELETE_CHILD = 0x0040
FILE_READ_ATTRIBUTES = 0x0080
FILE_WRITE_ATTRIBUTES = 0x0100
DELETE = 0x00010000
READ_CONTROL = 0x00020000
WRITE_DAC = 0x00040000
WRITE_OWNER = 0x00080000
SYNCHRONIZE = 0x00100000
STANDARD_RIGHTS_ALL = 0x001F0000
filemask = ldm & STANDARD_RIGHTS_ALL
if (ldm & RIGHT_DS_READ_PROPERTY) and (ldm & RIGHT_DS_LIST_CONTENTS):
filemask = filemask | (SYNCHRONIZE | FILE_LIST_DIRECTORY |
FILE_READ_ATTRIBUTES | FILE_READ_EA |
FILE_READ_DATA | FILE_EXECUTE)
if ldm & RIGHT_DS_WRITE_PROPERTY:
filemask = filemask | (SYNCHRONIZE | FILE_WRITE_DATA |
FILE_APPEND_DATA | FILE_WRITE_EA |
FILE_WRITE_ATTRIBUTES | FILE_ADD_FILE |
FILE_ADD_SUBDIRECTORY)
if ldm & RIGHT_DS_CREATE_CHILD:
filemask = filemask | (FILE_ADD_SUBDIRECTORY | FILE_ADD_FILE)
if ldm & RIGHT_DS_DELETE_CHILD:
filemask = filemask | FILE_DELETE_CHILD
return filemask
def dsacl2fsacl(dssddl, domsid):
"""
This function takes an the SDDL representation of a DS
ACL and return the SDDL representation of this ACL adapted
for files. It's used for Policy object provision
"""
sid = security.dom_sid(domsid)
ref = security.descriptor.from_sddl(dssddl, sid)
fdescr = security.descriptor()
fdescr.owner_sid = ref.owner_sid
fdescr.group_sid = ref.group_sid
fdescr.type = ref.type
fdescr.revision = ref.revision
fdescr.sacl = ref.sacl
aces = ref.dacl.aces
for i in range(0, len(aces)):
ace = aces[i]
if not ace.type & security.SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT and str(ace.trustee) != security.SID_BUILTIN_PREW2K:
# if fdescr.type & security.SEC_DESC_DACL_AUTO_INHERITED:
ace.flags = ace.flags | security.SEC_ACE_FLAG_OBJECT_INHERIT | security.SEC_ACE_FLAG_CONTAINER_INHERIT
if str(ace.trustee) == security.SID_CREATOR_OWNER:
# For Creator/Owner the IO flag is set as this ACE has only a sense for child objects
ace.flags = ace.flags | security.SEC_ACE_FLAG_INHERIT_ONLY
ace.access_mask = ldapmask2filemask(ace.access_mask)
fdescr.dacl_add(ace)
return fdescr.as_sddl(sid)