python/samba/__init__.py

   1 # Unix SMB/CIFS implementation.
   2 # Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2007-2008
   3 #
   4 # Based on the original in EJS:
   5 # Copyright (C) Andrew Tridgell <tridge@samba.org> 2005
   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 """Samba 4."""
  22
  23 __docformat__ = "restructuredText"
  24
  25 import os
  26 import sys
  27 import samba.param
  28
  29
  30 def source_tree_topdir():
  31     """Return the top level source directory."""
  32     paths = ["../../..", "../../../.."]
  33     for p in paths:
  34         topdir = os.path.normpath(os.path.join(os.path.dirname(__file__), p))
  35         if os.path.exists(os.path.join(topdir, 'source4')):
  36             return topdir
  37     raise RuntimeError("unable to find top level source directory")
  38
  39
  40 def in_source_tree():
  41     """Return True if we are running from within the samba source tree"""
  42     try:
  43         topdir = source_tree_topdir()
  44     except RuntimeError:
  45         return False
  46     return True
  47
  48
  49 import ldb
  50 from samba._ldb import Ldb as _Ldb
  51
  52
  53 class Ldb(_Ldb):
  54     """Simple Samba-specific LDB subclass that takes care
  55     of setting up the modules dir, credentials pointers, etc.
  56
  57     Please note that this is intended to be for all Samba LDB files,
  58     not necessarily the Sam database. For Sam-specific helper
  59     functions see samdb.py.
  60     """
  61
  62     def __init__(self, url=None, lp=None, modules_dir=None, session_info=None,
  63                  credentials=None, flags=0, options=None):
  64         """Opens a Samba Ldb file.
  65
  66         :param url: Optional LDB URL to open
  67         :param lp: Optional loadparm object
  68         :param modules_dir: Optional modules directory
  69         :param session_info: Optional session information
  70         :param credentials: Optional credentials, defaults to anonymous.
  71         :param flags: Optional LDB flags
  72         :param options: Additional options (optional)
  73
  74         This is different from a regular Ldb file in that the Samba-specific
  75         modules-dir is used by default and that credentials and session_info
  76         can be passed through (required by some modules).
  77         """
  78
  79         if modules_dir is not None:
  80             self.set_modules_dir(modules_dir)
  81         else:
  82             self.set_modules_dir(os.path.join(samba.param.modules_dir(), "ldb"))
  83
  84         if session_info is not None:
  85             self.set_session_info(session_info)
  86
  87         if credentials is not None:
  88             self.set_credentials(credentials)
  89
  90         if lp is not None:
  91             self.set_loadparm(lp)
  92
  93         # This must be done before we load the schema, as these handlers for
  94         # objectSid and objectGUID etc must take precedence over the 'binary
  95         # attribute' declaration in the schema
  96         self.register_samba_handlers()
  97
  98         # TODO set debug
  99         def msg(l, text):
 100             print text
 101         #self.set_debug(msg)
 102
 103         self.set_utf8_casefold()
 104
 105         # Allow admins to force non-sync ldb for all databases
 106         if lp is not None:
 107             nosync_p = lp.get("nosync", "ldb")
 108             if nosync_p is not None and nosync_p:
 109                 flags |= ldb.FLG_NOSYNC
 110
 111         self.set_create_perms(0600)
 112
 113         if url is not None:
 114             self.connect(url, flags, options)
 115
 116     def searchone(self, attribute, basedn=None, expression=None,
 117                   scope=ldb.SCOPE_BASE):
 118         """Search for one attribute as a string.
 119
 120         :param basedn: BaseDN for the search.
 121         :param attribute: Name of the attribute
 122         :param expression: Optional search expression.
 123         :param scope: Search scope (defaults to base).
 124         :return: Value of attribute as a string or None if it wasn't found.
 125         """
 126         res = self.search(basedn, scope, expression, [attribute])
 127         if len(res) != 1 or res[0][attribute] is None:
 128             return None
 129         values = set(res[0][attribute])
 130         assert len(values) == 1
 131         return self.schema_format_value(attribute, values.pop())
 132
 133     def erase_users_computers(self, dn):
 134         """Erases user and computer objects from our AD.
 135
 136         This is needed since the 'samldb' module denies the deletion of primary
 137         groups. Therefore all groups shouldn't be primary somewhere anymore.
 138         """
 139
 140         try:
 141             res = self.search(base=dn, scope=ldb.SCOPE_SUBTREE, attrs=[],
 142                       expression="(|(objectclass=user)(objectclass=computer))")
 143         except ldb.LdbError, (errno, _):
 144             if errno == ldb.ERR_NO_SUCH_OBJECT:
 145                 # Ignore no such object errors
 146                 return
 147             else:
 148                 raise
 149
 150         try:
 151             for msg in res:
 152                 self.delete(msg.dn, ["relax:0"])
 153         except ldb.LdbError, (errno, _):
 154             if errno != ldb.ERR_NO_SUCH_OBJECT:
 155                 # Ignore no such object errors
 156                 raise
 157
 158     def erase_except_schema_controlled(self):
 159         """Erase this ldb.
 160
 161         :note: Removes all records, except those that are controlled by
 162             Samba4's schema.
 163         """
 164
 165         basedn = ""
 166
 167         # Try to delete user/computer accounts to allow deletion of groups
 168         self.erase_users_computers(basedn)
 169
 170         # Delete the 'visible' records, and the invisble 'deleted' records (if
 171         # this DB supports it)
 172         for msg in self.search(basedn, ldb.SCOPE_SUBTREE,
 173                        "(&(|(objectclass=*)(distinguishedName=*))(!(distinguishedName=@BASEINFO)))",
 174                        [], controls=["show_deleted:0", "show_recycled:0"]):
 175             try:
 176                 self.delete(msg.dn, ["relax:0"])
 177             except ldb.LdbError, (errno, _):
 178                 if errno != ldb.ERR_NO_SUCH_OBJECT:
 179                     # Ignore no such object errors
 180                     raise
 181
 182         res = self.search(basedn, ldb.SCOPE_SUBTREE,
 183             "(&(|(objectclass=*)(distinguishedName=*))(!(distinguishedName=@BASEINFO)))",
 184             [], controls=["show_deleted:0", "show_recycled:0"])
 185         assert len(res) == 0
 186
 187         # delete the specials
 188         for attr in ["@SUBCLASSES", "@MODULES",
 189                      "@OPTIONS", "@PARTITION", "@KLUDGEACL"]:
 190             try:
 191                 self.delete(attr, ["relax:0"])
 192             except ldb.LdbError, (errno, _):
 193                 if errno != ldb.ERR_NO_SUCH_OBJECT:
 194                     # Ignore missing dn errors
 195                     raise
 196
 197     def erase(self):
 198         """Erase this ldb, removing all records."""
 199         self.erase_except_schema_controlled()
 200
 201         # delete the specials
 202         for attr in ["@INDEXLIST", "@ATTRIBUTES"]:
 203             try:
 204                 self.delete(attr, ["relax:0"])
 205             except ldb.LdbError, (errno, _):
 206                 if errno != ldb.ERR_NO_SUCH_OBJECT:
 207                     # Ignore missing dn errors
 208                     raise
 209
 210     def load_ldif_file_add(self, ldif_path):
 211         """Load a LDIF file.
 212
 213         :param ldif_path: Path to LDIF file.
 214         """
 215         self.add_ldif(open(ldif_path, 'r').read())
 216
 217     def add_ldif(self, ldif, controls=None):
 218         """Add data based on a LDIF string.
 219
 220         :param ldif: LDIF text.
 221         """
 222         for changetype, msg in self.parse_ldif(ldif):
 223             assert changetype == ldb.CHANGETYPE_NONE
 224             self.add(msg, controls)
 225
 226     def modify_ldif(self, ldif, controls=None):
 227         """Modify database based on a LDIF string.
 228
 229         :param ldif: LDIF text.
 230         """
 231         for changetype, msg in self.parse_ldif(ldif):
 232             if changetype == ldb.CHANGETYPE_ADD:
 233                 self.add(msg, controls)
 234             else:
 235                 self.modify(msg, controls)
 236
 237
 238 def substitute_var(text, values):
 239     """Substitute strings of the form ${NAME} in str, replacing
 240     with substitutions from values.
 241
 242     :param text: Text in which to subsitute.
 243     :param values: Dictionary with keys and values.
 244     """
 245
 246     for (name, value) in values.items():
 247         assert isinstance(name, str), "%r is not a string" % name
 248         assert isinstance(value, str), "Value %r for %s is not a string" % (value, name)
 249         text = text.replace("${%s}" % name, value)
 250
 251     return text
 252
 253
 254 def check_all_substituted(text):
 255     """Check that all substitution variables in a string have been replaced.
 256
 257     If not, raise an exception.
 258
 259     :param text: The text to search for substitution variables
 260     """
 261     if not "${" in text:
 262         return
 263
 264     var_start = text.find("${")
 265     var_end = text.find("}", var_start)
 266
 267     raise Exception("Not all variables substituted: %s" %
 268         text[var_start:var_end+1])
 269
 270
 271 def read_and_sub_file(file_name, subst_vars):
 272     """Read a file and sub in variables found in it
 273
 274     :param file_name: File to be read (typically from setup directory)
 275      param subst_vars: Optional variables to subsitute in the file.
 276     """
 277     data = open(file_name, 'r').read()
 278     if subst_vars is not None:
 279         data = substitute_var(data, subst_vars)
 280         check_all_substituted(data)
 281     return data
 282
 283
 284 def setup_file(template, fname, subst_vars=None):
 285     """Setup a file in the private dir.
 286
 287     :param template: Path of the template file.
 288     :param fname: Path of the file to create.
 289     :param subst_vars: Substitution variables.
 290     """
 291     if os.path.exists(fname):
 292         os.unlink(fname)
 293
 294     data = read_and_sub_file(template, subst_vars)
 295     f = open(fname, 'w')
 296     try:
 297         f.write(data)
 298     finally:
 299         f.close()
 300
 301 MAX_NETBIOS_NAME_LEN = 15
 302 def is_valid_netbios_char(c):
 303     return (c.isalnum() or c in " !#$%&'()-.@^_{}~")
 304
 305
 306 def valid_netbios_name(name):
 307     """Check whether a name is valid as a NetBIOS name. """
 308     # See crh's book (1.4.1.1)
 309     if len(name) > MAX_NETBIOS_NAME_LEN:
 310         return False
 311     for x in name:
 312         if not is_valid_netbios_char(x):
 313             return False
 314     return True
 315
 316
 317 def import_bundled_package(modulename, location):
 318     """Import the bundled version of a package.
 319
 320     :note: This should only be called if the system version of the package
 321         is not adequate.
 322
 323     :param modulename: Module name to import
 324     :param location: Location to add to sys.path (can be relative to
 325         ${srcdir}/lib)
 326     """
 327     if in_source_tree():
 328         sys.path.insert(0, os.path.join(source_tree_topdir(), "lib", location))
 329         sys.modules[modulename] = __import__(modulename)
 330     else:
 331         sys.modules[modulename] = __import__(
 332             "samba.external.%s" % modulename, fromlist=["samba.external"])
 333
 334
 335 def ensure_external_module(modulename, location):
 336     """Add a location to sys.path if an external dependency can't be found.
 337
 338     :param modulename: Module name to import
 339     :param location: Location to add to sys.path (can be relative to
 340         ${srcdir}/lib)
 341     """
 342     try:
 343         __import__(modulename)
 344     except ImportError:
 345         import_bundled_package(modulename, location)
 346
 347
 348 def dn_from_dns_name(dnsdomain):
 349     """return a DN from a DNS name domain/forest root"""
 350     return "DC=" + ",DC=".join(dnsdomain.split("."))
 351
 352 import _glue
 353 version = _glue.version
 354 interface_ips = _glue.interface_ips
 355 set_debug_level = _glue.set_debug_level
 356 get_debug_level = _glue.get_debug_level
 357 unix2nttime = _glue.unix2nttime
 358 nttime2string = _glue.nttime2string
 359 nttime2unix = _glue.nttime2unix
 360 unix2nttime = _glue.unix2nttime
 361 generate_random_password = _glue.generate_random_password
 362 strcasecmp_m = _glue.strcasecmp_m
 363 strstr_m = _glue.strstr_m