summaryrefslogtreecommitdiffstats
path: root/accounts/backend/user/ldap.py
blob: 6ab02c64be6f2ea0f0ec48a240821859c46344fe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
# -*- coding: utf-8 -*-
from __future__ import absolute_import

import ldap3
from ldap3.utils.conv import escape_filter_chars
from ldap3.utils.dn import escape_attribute_value

from . import Backend, InvalidPasswordError, NoSuchUserError
from accounts.models import Account


def _escape(value, wildcard=False):
    if not wildcard:
        value = escape_filter_chars(value)
    return escape_attribute_value(value)


def _change_password(conn, dn, passwords, as_admin=False):
    old_password, new_password = passwords
    if as_admin:
        conn.extend.standard.modify_password(dn, None, new_password)
    else:
        try:
            conn.extend.standard.modify_password(dn, old_password,
                                                 new_password)
        except ldap3.LDAPException:
            raise InvalidPasswordError('Invalid password')


class LdapBackend(Backend):

    def __init__(self, app):
        super(LdapBackend, self).__init__(app)

        self.host = self.app.config['LDAP_HOST']
        self.base_dn = self.app.config['LDAP_BASE_DN']
        self.admin_user = self.app.config['LDAP_ADMIN_USER']
        self.admin_pass = self.app.config['LDAP_ADMIN_PASS']
        self.services = self.app.all_services

        self.admin = False
        self.binded = False

    def auth(self, username, password):
        """
        Tries to authenticate a user with a given password. If the
        authentication is successful an Account object will be returned.
        """
        user_dn = self._format_dn([('uid', username), ('ou', 'users')])
        conn = self._connect(user_dn, password)

        uid = None
        mail = None
        services = []
        conn.search(user_dn, '(objectClass=*)',
                    attributes=['objectClass', 'uid', 'mail', 'cn'])
        for entry in conn.entries:
            if 'inetOrgPerson' in entry.objectClass.values:
                uid = entry.uid.value
                mail = entry.mail.value
            elif 'servicePassword' in entry.objectClass.value:
                services.append(entry.cn.value)

        if uid is None or mail is None:
            raise NoSuchUserError("User not found")

        return Account(uid, mail, services, password)

    def find(self, filters=None, wildcard=False):
        """
        Find accounts by a given filter.
        """
        if filters is None:
            filters = dict()

        filters['objectClass'] = 'inetOrgPerson'
        filter_as_list = ['(%s=%s)' % (attr, _escape(value, wildcard))
                          for attr, value in filters.items()]
        filterstr = '(&%s)' % ''.join(filter_as_list)

        conn = self._connect()
        base_dn = self._format_dn([('ou', 'users')])

        accounts = []
        try:
            conn.search(base_dn, filterstr, search_scope=ldap3.LEVEL,
                        attributes=['uid', 'mail'])
            for entry in conn.entries:
                accounts.append(Account(entry.uid.value, entry.mail.value))
        except ldap3.LDAPException:
            pass

        return accounts

    def register(self, account):
        """
        Persists an account in the backend.
        """
        conn = self._connect_as_admin()

        user_dn = self._format_dn([('uid', account.uid), ('ou', 'users')])
        attrs = {
            'objectClass': ['top', 'inetOrgPerson'],
            'uid': _escape(account.uid),
            'sn': 'n/a',
            'cn': _escape(account.uid),
            'mail': _escape(account.mail),
        }

        conn.add(user_dn, attributes=attrs)
        account.new_password_root = (None, account.password)
        self._alter_passwords(conn, account)

    def update(self, account, as_admin=False):
        """
        Updates account informations like passwords or email.
        """
        conn = None
        user_dn = self._format_dn([('uid', account.uid), ('ou', 'users')])
        if as_admin:
            conn = self._connect_as_admin()
        else:
            conn = self._connect(user_dn, account.password)

        attrs = {key: [(ldap3.MODIFY_REPLACE, [value])]
                 for key, value in account.attributes.items()}
        conn.modify(user_dn, attrs)
        self._alter_passwords(conn, account, as_admin=as_admin)

    def delete(self, account, as_admin=False):
        """
        Deletes an account permanently.
        """
        conn = None
        if as_admin:
            conn = self._connect_as_admin()
        else:
            conn = self._connect(account.uid, account.password)

        dns = [[('cn', service.id), ('uid', account.uid), ('ou', 'users')]
               for service in account.services] + \
              [[('uid', account.uid), ('ou', 'users')]]

        for dn in dns:
            conn.delete(self._format_dn(dn))

    def _format_dn(self, attr, with_base_dn=True):
        if with_base_dn:
            attr.extend(self.base_dn)

        dn = ['%s=%s' % (item[0], _escape(item[1]))
              for item in attr]

        return ','.join(dn)

    def _connect(self, user=None, password=None):
        server = ldap3.Server(self.host)
        conn = ldap3.Connection(server, user, password, raise_exceptions=True)

        try:
            conn.bind()
        except ldap3.LDAPInvalidCredentialsResult:
            raise InvalidPasswordError('Invalid password')

        return conn

    def _connect_as_admin(self):
        admin_dn = self._format_dn([('cn', self.admin_user)])
        return self._connect(admin_dn, self.admin_pass)

    def _alter_passwords(self, conn, account, as_admin=False):
        if account.new_password_root:
            user_dn = self._format_dn([('uid', account.uid), ('ou', 'users')])
            _change_password(conn, user_dn, account.new_password_root, as_admin)
            _, account.password = account.new_password_root
            account.new_password_root = None

        for service, passwords in account.new_password_services.items():
            service_id = service.lower()
            service_dn = self._format_dn([('cn', service_id), ('uid', account.uid),
                                          ('ou', 'users')])
            _, new = passwords

            if new != None:
                if service_id not in account.services:
                    attrs = {
                        'objectClass': ['top', 'servicePassword'],
                        'cn': _escape(service_id),
                    }
                    conn.add(service_dn, attributes=attrs)
                    account.services.append(service_id)

                _change_password(conn, service_dn, passwords, as_admin)
            else:
                if service_id in account.services:
                    conn.delete(service_dn)
                    account.services.remove(service_id)

            del account.new_password_services[service]