appypod-rattail/shared/ldap_connector.py

277 lines
13 KiB
Python

# ------------------------------------------------------------------------------
import string
try:
import ldap
except ImportError:
# For people that do not care about ldap
ldap = None
# ------------------------------------------------------------------------------
class LdapConfig:
'''Parameters for authenticating users to an LDAP server. This class is
used by gen-applications. For a pure, appy-independent LDAP connector,
see the class LdapConnector below.'''
ldapAttributes = { 'loginAttribute':None, 'emailAttribute':'email',
'fullNameAttribute':'title',
'firstNameAttribute':'firstName',
'lastNameAttribute':'name' }
def __init__(self):
self.server = '' # Name of the LDAP server
self.port = None # Port for this server.
# Login and password of the technical power user that the Appy
# application will use to connect to the LDAP.
self.adminLogin = ''
self.adminPassword = ''
# LDAP attribute to use as login for authenticating users.
self.loginAttribute = 'dn' # Can also be "mail", "sAMAccountName", "cn"
# LDAP attributes for storing email
self.emailAttribute = None
# LDAP attribute for storing full name (first + last name)
self.fullNameAttribute = None
# Alternately, LDAP attributes for storing 1st & last names separately.
self.firstNameAttribute = None
self.lastNameAttribute = None
# LDAP classes defining the users stored in the LDAP.
self.userClasses = ('top', 'person')
self.baseDn = '' # Base DN where to find users in the LDAP.
self.scope = 'SUBTREE' # Scope of the search within self.baseDn
# Is this server connection enabled ?
self.enabled = True
# The "user map" allows to put LDAP users into groups or assign them
# roles. This dict will be used every time a local User will be created.
# It can be while synchronizing all users (see m_synchronizeUsers
# below) or when the user logs in for the first time (see m_getUser
# below). This dict will NOT be used subsequently, when updating the
# User instance. Every key must be a user login. Every value is an
# appy.Object instance having the optional attributes:
# "groups": a list of group IDs (logins);
# "roles": a list of global role names.
self.userMap = {}
def getServerUri(self):
'''Returns the complete URI for accessing the LDAP, ie
"ldap://some.ldap.server:389".'''
port = self.port or 389
return 'ldap://%s:%d' % (self.server, port)
def getUserFilterValues(self, login=None):
'''Gets the filter values required to perform a query for finding user
corresponding to p_login in the LDAP, or all users if p_login is
None.'''
res = login and [(self.loginAttribute, login)] or []
for userClass in self.userClasses:
res.append( ('objectClass', userClass) )
return res
def getUserAttributes(self):
'''Gets the attributes we want to get from the LDAP for characterizing
a user.'''
res = []
for name in self.ldapAttributes.iterkeys():
if getattr(self, name):
res.append(getattr(self, name))
return res
def getUserParams(self, ldapData):
'''Formats the user-related p_ldapData retrieved from the ldap, as a
dict of params usable for creating or updating the corresponding
Appy user.'''
res = {}
for name, appyName in self.ldapAttributes.iteritems():
if not appyName: continue
# Get the name of the attribute as known in the LDAP
ldapName = getattr(self, name)
if not ldapName: continue
if ldapData.has_key(ldapName) and ldapData[ldapName]:
value = ldapData[ldapName]
if isinstance(value, list): value = value[0]
res[appyName] = value
return res
def setLocalUser(self, tool, attrs, login, password=None):
'''Creates or updates the local User instance corresponding to a LDAP
user from the LDAP, having p_login. Its other attributes are in
p_attrs and, when relevant, its password is in p_password. This
method returns a 2-tuple containing:
* the local User instance;
* the status of the operation:
- "created" if the instance has been created,
- "updated" if at least one data from p_attrs is different from the
one stored on the existing User instance;
- None else.
'''
# Do we already have a local User instance for this user ?
status = None
user = tool.search1('User', noSecurity=True, login=login)
if user:
# Yes. Update it with info about him from the LDAP
for name, value in attrs.iteritems():
currentValue = getattr(user, name)
if value != currentValue:
setattr(user, name, value)
status = 'updated'
# Update user password, if given
if password: user.setPassword(password, log=False)
user.reindex()
else:
# Create the user
user = tool.create('users', noSecurity=True, login=login,
source='ldap', **attrs)
if password: user.setPassword(password, log=False)
status = 'created'
# Put him into groups and/or grant him some roles according to
# self.userMap.
if login in self.userMap:
privileges = self.userMap[login]
# Put the user in some groups
groups = getattr(privileges, 'groups', None)
if groups:
for groupLogin in groups:
group = tool.search1('Group', noSecurity=True,
login=groupLogin)
group.link('users', user)
# Grant him some roles
roles = getattr(privileges, 'roles', None)
if roles:
for role in roles: user.addRole(role)
tool.log('%s: automatic privileges set.' % login)
return user, status
def getUser(self, tool, login, password):
'''Returns a local User instance corresponding to a LDAP user if p_login
and p_password correspond to a valid LDAP user.'''
# Check if LDAP is enabled
if not self.enabled: return
# Get a connector to the LDAP server and connect to the LDAP server
serverUri = self.getServerUri()
connector = LdapConnector(serverUri, tool=tool)
success, msg = connector.connect(self.adminLogin, self.adminPassword)
if not success: return
# Check if the user corresponding to p_login exists in the LDAP
filter = connector.getFilter(self.getUserFilterValues(login))
params = self.getUserAttributes()
ldapData = connector.search(self.baseDn, self.scope, filter, params)
if not ldapData: return
# The user exists. Try to connect to the LDAP with this user in order
# to validate its password.
userConnector = LdapConnector(serverUri, tool=tool)
success, msg = userConnector.connect(ldapData[0][0], password)
if not success: return
# The password is correct. We can create/update our local user
# corresponding to this LDAP user.
userParams = self.getUserParams(ldapData[0][1])
user, status = self.setLocalUser(tool, userParams, login, password)
return user
def synchronizeUsers(self, tool):
'''Synchronizes the local User copies with this LDAP user base. Returns
a 2-tuple containing the number of created, updated and untouched
local copies.'''
if not self.enabled: raise Exception('LDAP config not enabled.')
# Get a connector to the LDAP server and connect to the LDAP server
serverUri = self.getServerUri()
tool.log('reading users from %s...' % serverUri)
connector = LdapConnector(serverUri, tool=tool)
success, msg = connector.connect(self.adminLogin, self.adminPassword)
if not success: raise Exception('Could not connect to %s' % serverUri)
# Query the LDAP for users. Perform several queries to avoid having
# error ldap.SIZELIMIT_EXCEEDED.
params = self.getUserAttributes()
# Count the number of created, updated and untouched users
created = updated = untouched = 0
for letter in string.ascii_lowercase:
# Get all the users whose login starts with "letter"
filter = connector.getFilter(self.getUserFilterValues('%s*'%letter))
ldapData = connector.search(self.baseDn, self.scope, filter, params)
if not ldapData: continue
for userData in ldapData:
# Get the user login
login = userData[1][self.loginAttribute][0]
# Get the other user parameters, as Appy wants it
userParams = self.getUserParams(userData[1])
# Create or update the user
user, status = self.setLocalUser(tool, userParams, login)
if status == 'created': created += 1
elif status == 'updated': updated += 1
else: untouched += 1
tool.log('users synchronization: %d local user(s) created, ' \
'%d updated and %d untouched.'% (created, updated, untouched))
return created, updated, untouched
# ------------------------------------------------------------------------------
class LdapConnector:
'''This class manages the communication with a LDAP server.'''
def __init__(self, serverUri, tentatives=5, ssl=False, timeout=5,
tool=None):
# The URI of the LDAP server, ie ldap://some.ldap.server:389.
self.serverUri = serverUri
# The object that will represent the LDAP server
self.server = None
# The number of trials the connector will at most perform to the LDAP
# server, when executing a query in it.
self.tentatives = tentatives
self.ssl = ssl
# The timeout for every query to the LDAP.
self.timeout = timeout
# A tool from a Appy application can be given and will be used, ie for
# logging purpose.
self.tool = tool
def log(self, message, type='info'):
'''Logs via a Appy tool if available.'''
if self.tool:
self.tool.log(message, type=type)
else:
print(message)
def connect(self, login, password):
'''Connects to the LDAP server using p_login and p_password as
credentials. If the connection succeeds, a server object is created
in self.server and tuple (True, None) is returned. Else, tuple
(False, errorMessage) is returned.'''
try:
self.server = ldap.initialize(self.serverUri)
self.server.simple_bind_s(login, password)
return True, None
except AttributeError, ae:
# When the ldap module is not there, trying to catch ldap.LDAPError
# will raise an error.
message = str(ae)
self.log('Ldap connect error with login %s (%s).' % \
(login, message))
return False, message
except ldap.LDAPError, le:
message = str(le)
self.log('%s: connect error with login %s (%s).' % \
(self.serverUri, login, message))
return False, message
def getFilter(self, values):
'''Builds and returns a LDAP filter based on p_values, a tuple or list
of tuples (name,value).'''
return '(&%s)' % ''.join(['(%s=%s)' % (n, v) for n, v in values])
def search(self, baseDn, scope, filter, attributes=None):
'''Performs a query in the LDAP at node p_baseDn, with the given
p_scope. p_filter is a LDAP filter that constraints the search. It
can be computed from a list of tuples (value, name) by method
m_getFilter. p_attributes is the list of attributes that we will
retrieve from the LDAP. If None, all attributes will be retrieved.'''
if self.ssl: self.server.start_tls_s()
try:
# Get the LDAP constant corresponding to p_scope.
scope = getattr(ldap, 'SCOPE_%s' % scope)
# Perform the query.
for i in range(self.tentatives):
try:
return self.server.search_st(\
baseDn, scope, filterstr=filter, attrlist=attributes,
timeout=self.timeout)
except ldap.TIMEOUT:
pass
except ldap.LDAPError, le:
self.log('LDAP query error %s: %s' % \
(le.__class__.__name__, str(le)))
# ------------------------------------------------------------------------------