source4/scripting/python/samba/ntacls.py

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