authentik/passbook/sources/ldap/connector.py

229 lines
9.5 KiB
Python

"""Wrapper for ldap3 to easily manage user"""
from typing import Any, Dict, Optional
import ldap3
import ldap3.core.exceptions
from django.db.utils import IntegrityError
from structlog import get_logger
from passbook.core.exceptions import PropertyMappingExpressionException
from passbook.core.models import Group, User
from passbook.sources.ldap.models import LDAPPropertyMapping, LDAPSource
LOGGER = get_logger()
class Connector:
"""Wrapper for ldap3 to easily manage user authentication and creation"""
_source: LDAPSource
def __init__(self, source: LDAPSource):
self._source = source
@staticmethod
def encode_pass(password: str) -> bytes:
"""Encodes a plain-text password so it can be used by AD"""
return '"{}"'.format(password).encode("utf-16-le")
@property
def base_dn_users(self) -> str:
"""Shortcut to get full base_dn for user lookups"""
if self._source.additional_user_dn:
return f"{self._source.additional_user_dn},{self._source.base_dn}"
return self._source.base_dn
@property
def base_dn_groups(self) -> str:
"""Shortcut to get full base_dn for group lookups"""
if self._source.additional_group_dn:
return f"{self._source.additional_group_dn},{self._source.base_dn}"
return self._source.base_dn
def sync_groups(self):
"""Iterate over all LDAP Groups and create passbook_core.Group instances"""
if not self._source.sync_groups:
LOGGER.warning("Group syncing is disabled for this Source")
return
groups = self._source.connection.extend.standard.paged_search(
search_base=self.base_dn_groups,
search_filter=self._source.group_object_filter,
search_scope=ldap3.SUBTREE,
attributes=ldap3.ALL_ATTRIBUTES,
)
for group in groups:
attributes = group.get("attributes", {})
if self._source.object_uniqueness_field not in attributes:
LOGGER.warning(
"Cannot find uniqueness Field in attributes", user=attributes.keys()
)
continue
uniq = attributes[self._source.object_uniqueness_field]
_, created = Group.objects.update_or_create(
attributes__ldap_uniq=uniq,
parent=self._source.sync_parent_group,
defaults={
"name": attributes.get("name", ""),
"attributes": {
"ldap_uniq": uniq,
"distinguishedName": attributes.get("distinguishedName"),
},
},
)
LOGGER.debug(
"Synced group", group=attributes.get("name", ""), created=created
)
def sync_users(self):
"""Iterate over all LDAP Users and create passbook_core.User instances"""
if not self._source.sync_users:
LOGGER.warning("User syncing is disabled for this Source")
return
users = self._source.connection.extend.standard.paged_search(
search_base=self.base_dn_users,
search_filter=self._source.user_object_filter,
search_scope=ldap3.SUBTREE,
attributes=ldap3.ALL_ATTRIBUTES,
)
for user in users:
attributes = user.get("attributes", {})
if self._source.object_uniqueness_field not in attributes:
LOGGER.warning(
"Cannot find uniqueness Field in attributes", user=user.keys()
)
continue
uniq = attributes[self._source.object_uniqueness_field]
try:
defaults = self._build_object_properties(attributes)
user, created = User.objects.update_or_create(
attributes__ldap_uniq=uniq, defaults=defaults,
)
except IntegrityError as exc:
LOGGER.warning("Failed to create user", exc=exc)
LOGGER.warning(
(
"To merge new User with existing user, set the User's "
f"Attribute 'ldap_uniq' to '{uniq}'"
)
)
else:
if created:
user.set_unusable_password()
user.save()
LOGGER.debug(
"Synced User", user=attributes.get("name", ""), created=created
)
def sync_membership(self):
"""Iterate over all Users and assign Groups using memberOf Field"""
users = self._source.connection.extend.standard.paged_search(
search_base=self.base_dn_users,
search_filter=self._source.user_object_filter,
search_scope=ldap3.SUBTREE,
attributes=[
self._source.user_group_membership_field,
self._source.object_uniqueness_field,
],
)
group_cache: Dict[str, Group] = {}
for user in users:
member_of = user.get("attributes", {}).get(
self._source.user_group_membership_field, []
)
uniq = user.get("attributes", {}).get(
self._source.object_uniqueness_field, []
)
for group_dn in member_of:
# Check if group_dn is within our base_dn_groups, and skip if not
if not group_dn.endswith(self.base_dn_groups):
continue
# Check if we fetched the group already, and if not cache it for later
if group_dn not in group_cache:
groups = Group.objects.filter(
attributes__distinguishedName=group_dn
)
if not groups.exists():
LOGGER.warning(
"Group does not exist in our DB yet, run sync_groups first.",
group=group_dn,
)
return
group_cache[group_dn] = groups.first()
group = group_cache[group_dn]
users = User.objects.filter(attributes__ldap_uniq=uniq)
group.user_set.add(*list(users))
# Now that all users are added, lets write everything
for _, group in group_cache.items():
group.save()
LOGGER.debug("Successfully updated group membership")
def _build_object_properties(
self, attributes: Dict[str, Any]
) -> Dict[str, Dict[Any, Any]]:
properties = {"attributes": {}}
for mapping in self._source.property_mappings.all().select_subclasses():
if not isinstance(mapping, LDAPPropertyMapping):
continue
mapping: LDAPPropertyMapping
try:
value = mapping.evaluate(user=None, request=None, ldap=attributes)
if value is None:
continue
properties[mapping.object_field] = value
except PropertyMappingExpressionException as exc:
LOGGER.warning("Mapping failed to evaluate", exc=exc, mapping=mapping)
continue
if self._source.object_uniqueness_field in attributes:
properties["attributes"]["ldap_uniq"] = attributes.get(
self._source.object_uniqueness_field
)
properties["attributes"]["distinguishedName"] = attributes.get(
"distinguishedName"
)
return properties
def auth_user(self, password: str, **filters: str) -> Optional[User]:
"""Try to bind as either user_dn or mail with password.
Returns True on success, otherwise False"""
users = User.objects.filter(**filters)
if not users.exists():
return None
user: User = users.first()
if "distinguishedName" not in user.attributes:
LOGGER.debug(
"User doesn't have DN set, assuming not LDAP imported.", user=user
)
return None
# Either has unusable password,
# or has a password, but couldn't be authenticated by ModelBackend.
# This means we check with a bind to see if the LDAP password has changed
if self.auth_user_by_bind(user, password):
# Password given successfully binds to LDAP, so we save it in our Database
LOGGER.debug("Updating user's password in DB", user=user)
user.set_password(password)
user.save()
return user
# Password doesn't match
LOGGER.debug("Failed to bind, password invalid")
return None
def auth_user_by_bind(self, user: User, password: str) -> Optional[User]:
"""Attempt authentication by binding to the LDAP server as `user`. This
method should be avoided as its slow to do the bind."""
# Try to bind as new user
LOGGER.debug("Attempting Binding as user", user=user)
try:
temp_connection = ldap3.Connection(
self._source.connection.server,
user=user.attributes.get("distinguishedName"),
password=password,
raise_exceptions=True,
)
temp_connection.bind()
return user
except ldap3.core.exceptions.LDAPInvalidCredentialsResult as exception:
LOGGER.debug("LDAPInvalidCredentialsResult", user=user, error=exception)
except ldap3.core.exceptions.LDAPException as exception:
LOGGER.warning(exception)
return None