source4/scripting/python/samba/ntacls.py

   1 # Unix SMB/CIFS implementation.
   2 # Copyright (C) Matthieu Patou <mat@matws.net> 2009-2010
   3 #
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 3 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 #
  18
  19 """NT Acls."""
  20
  21
  22 import os
  23 import samba.xattr_native, samba.xattr_tdb, samba.posix_eadb
  24 from samba.dcerpc import security, xattr
  25 from samba.ndr import ndr_pack, ndr_unpack
  26
  27 class XattrBackendError(Exception):
  28     """A generic xattr backend error."""
  29
  30
  31 def checkset_backend(lp, backend, eadbfile):
  32     '''return the path to the eadb, or None'''
  33     if backend is None:
  34         xattr_tdb = lp.get("xattr_tdb:file")
  35         if xattr_tdb is not None:
  36             return (samba.xattr_tdb, lp.get("xattr_tdb:file"))
  37         posix_eadb = lp.get("posix:eadb")
  38         if posix_eadb is not None:
  39             return (samba.posix_eadb, lp.get("posix:eadb"))
  40         return (None, None)
  41     elif backend == "native":
  42         return (None, None)
  43     elif backend == "eadb":
  44         if eadbfile is not None:
  45             return (samba.posix_eadb, eadbfile)
  46         else:
  47             return (samba.posix_eadb, os.path.abspath(os.path.join(lp.get("private dir"), "eadb.tdb")))
  48     elif backend == "tdb":
  49         if eadbfile is not None:
  50             return (samba.xattr_tdb, eadbfile)
  51         else:
  52             return (samba.xattr_tdb, os.path.abspath(os.path.join(lp.get("state dir"), "xattr.tdb")))
  53     else:
  54         raise XattrBackendError("Invalid xattr backend choice %s"%backend)
  55
  56
  57 def getntacl(lp, file, backend=None, eadbfile=None):
  58     (backend_obj, dbname) = checkset_backend(lp, backend, eadbfile)
  59     if dbname is not None:
  60         try:
  61             attribute = backend_obj.wrap_getxattr(dbname, file,
  62                 xattr.XATTR_NTACL_NAME)
  63         except Exception:
  64             # FIXME: Don't catch all exceptions, just those related to opening
  65             # xattrdb
  66             print "Fail to open %s" % dbname
  67             attribute = samba.xattr_native.wrap_getxattr(file,
  68                 xattr.XATTR_NTACL_NAME)
  69     else:
  70         attribute = samba.xattr_native.wrap_getxattr(file,
  71             xattr.XATTR_NTACL_NAME)
  72     ntacl = ndr_unpack(xattr.NTACL, attribute)
  73     return ntacl
  74
  75
  76 def setntacl(lp, file, sddl, domsid, backend=None, eadbfile=None):
  77     (backend_obj, dbname) = checkset_backend(lp, backend, eadbfile)
  78     ntacl = xattr.NTACL()
  79     ntacl.version = 1
  80     sid = security.dom_sid(domsid)
  81     sd = security.descriptor.from_sddl(sddl, sid)
  82     ntacl.info = sd
  83     if dbname is not None:
  84         try:
  85             backend_obj.wrap_setxattr(dbname,
  86                 file, xattr.XATTR_NTACL_NAME, ndr_pack(ntacl))
  87         except Exception:
  88             # FIXME: Don't catch all exceptions, just those related to opening
  89             # xattrdb
  90             print "Fail to open %s" % dbname
  91             samba.xattr_native.wrap_setxattr(file, xattr.XATTR_NTACL_NAME,
  92                 ndr_pack(ntacl))
  93     else:
  94         samba.xattr_native.wrap_setxattr(file, xattr.XATTR_NTACL_NAME,
  95                 ndr_pack(ntacl))
  96
  97
  98 def ldapmask2filemask(ldm):
  99     """Takes the access mask of a DS ACE and transform them in a File ACE mask.
 100     """
 101     RIGHT_DS_CREATE_CHILD     = 0x00000001
 102     RIGHT_DS_DELETE_CHILD     = 0x00000002
 103     RIGHT_DS_LIST_CONTENTS    = 0x00000004
 104     ACTRL_DS_SELF             = 0x00000008
 105     RIGHT_DS_READ_PROPERTY    = 0x00000010
 106     RIGHT_DS_WRITE_PROPERTY   = 0x00000020
 107     RIGHT_DS_DELETE_TREE      = 0x00000040
 108     RIGHT_DS_LIST_OBJECT      = 0x00000080
 109     RIGHT_DS_CONTROL_ACCESS   = 0x00000100
 110     FILE_READ_DATA            = 0x0001
 111     FILE_LIST_DIRECTORY       = 0x0001
 112     FILE_WRITE_DATA           = 0x0002
 113     FILE_ADD_FILE             = 0x0002
 114     FILE_APPEND_DATA          = 0x0004
 115     FILE_ADD_SUBDIRECTORY     = 0x0004
 116     FILE_CREATE_PIPE_INSTANCE = 0x0004
 117     FILE_READ_EA              = 0x0008
 118     FILE_WRITE_EA             = 0x0010
 119     FILE_EXECUTE              = 0x0020
 120     FILE_TRAVERSE             = 0x0020
 121     FILE_DELETE_CHILD         = 0x0040
 122     FILE_READ_ATTRIBUTES      = 0x0080
 123     FILE_WRITE_ATTRIBUTES     = 0x0100
 124     DELETE                    = 0x00010000
 125     READ_CONTROL              = 0x00020000
 126     WRITE_DAC                 = 0x00040000
 127     WRITE_OWNER               = 0x00080000
 128     SYNCHRONIZE               = 0x00100000
 129     STANDARD_RIGHTS_ALL       = 0x001F0000
 130
 131     filemask = ldm & STANDARD_RIGHTS_ALL
 132
 133     if (ldm & RIGHT_DS_READ_PROPERTY) and (ldm & RIGHT_DS_LIST_CONTENTS):
 134         filemask = filemask | (SYNCHRONIZE | FILE_LIST_DIRECTORY |\
 135                                 FILE_READ_ATTRIBUTES | FILE_READ_EA |\
 136                                 FILE_READ_DATA | FILE_EXECUTE)
 137
 138     if ldm & RIGHT_DS_WRITE_PROPERTY:
 139         filemask = filemask | (SYNCHRONIZE | FILE_WRITE_DATA |\
 140                                 FILE_APPEND_DATA | FILE_WRITE_EA |\
 141                                 FILE_WRITE_ATTRIBUTES | FILE_ADD_FILE |\
 142                                 FILE_ADD_SUBDIRECTORY)
 143
 144     if ldm & RIGHT_DS_CREATE_CHILD:
 145         filemask = filemask | (FILE_ADD_SUBDIRECTORY | FILE_ADD_FILE)
 146
 147     if ldm & RIGHT_DS_DELETE_CHILD:
 148         filemask = filemask | FILE_DELETE_CHILD
 149
 150     return filemask
 151
 152
 153 def dsacl2fsacl(dssddl, domsid):
 154     """
 155
 156     This function takes an the SDDL representation of a DS
 157     ACL and return the SDDL representation of this ACL adapted
 158     for files. It's used for Policy object provision
 159     """
 160     sid = security.dom_sid(domsid)
 161     ref = security.descriptor.from_sddl(dssddl, sid)
 162     fdescr = security.descriptor()
 163     fdescr.owner_sid = ref.owner_sid
 164     fdescr.group_sid = ref.group_sid
 165     fdescr.type = ref.type
 166     fdescr.revision = ref.revision
 167     fdescr.sacl = ref.sacl
 168     aces = ref.dacl.aces
 169     for i in range(0, len(aces)):
 170         ace = aces[i]
 171         if not ace.type & security.SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT and str(ace.trustee) != security.SID_BUILTIN_PREW2K:
 172        #    if fdescr.type & security.SEC_DESC_DACL_AUTO_INHERITED:
 173             ace.flags = ace.flags | security.SEC_ACE_FLAG_OBJECT_INHERIT | security.SEC_ACE_FLAG_CONTAINER_INHERIT
 174             if str(ace.trustee) == security.SID_CREATOR_OWNER:
 175                 # For Creator/Owner the IO flag is set as this ACE has only a sense for child objects
 176                 ace.flags = ace.flags | security.SEC_ACE_FLAG_INHERIT_ONLY
 177             ace.access_mask =  ldapmask2filemask(ace.access_mask)
 178             fdescr.dacl_add(ace)
 179
 180     return fdescr.as_sddl(sid)