1 .TH SLAPO-NSSOV 5 "RELEASEDATE" "OpenLDAP LDVERSION"
2 .\" Copyright 1998-2009 The OpenLDAP Foundation, All Rights Reserved.
3 .\" Copying restrictions apply. See the COPYRIGHT file.
6 slapo-nssov \- NSS and PAM requests through a local Unix Domain socket
14 services NSS and PAM requests through a local Unix Domain socket.
15 It uses the same IPC protocol as Arthur de Jong's nss-ldapd, and
16 a complete copy of the nss-ldapd source is included along with the
19 Using a separate IPC protocol for NSS and PAM requests eliminates the
20 libldap dependencies/clashes that the current pam_ldap/nss_ldap solutions
21 all suffer from. Both the original nss-ldapd and this nssov solution
22 are free from these library issues.
24 Unlike nss-ldapd, since this overlay executes inside slapd it allows for
25 the possibility of sophisticated caching, without any of the weaknesses of
26 nscd and other related caching solutions. E.g., a remote LDAP database can
27 be accessed using back-ldap with proxy caching (see
31 ) to leverage back-ldap's
32 connection pooling as well as pcache's persistent caching, to provide
33 high performance and a measure of support for disconnected operation.
34 Alternatively, cache considerations can be completely eliminated by running
35 a regular database with syncrepl to maintain synchronization with a remote
38 Another major benefit of nssov is that it allows all security policy to be
39 administered centrally via LDAP, instead of having fragile rules scattered
40 across multiple flat files. As such, there is no client-side configuration at
41 all for the NSS/PAM stub libraries. (The stubs talk to the server via a Unix
42 domain socket whose path is hardcoded to /var/run/nslcd/). As a side benefit,
43 this can finally eliminate the perpetual confusion between OpenLDAP's
44 ldap.conf file in ETCDIR/ldap.conf and the similarly named files typically
45 used by pam_ldap and nss_ldap.
47 User authentication is performed by internal simple Binds. User authorization
48 leverages the slapd ACL engine, which offers much more power and flexibility
49 than the simple group/hostname checks in the old pam_ldap code.
51 To use this code, you will need the client-side stub library from
52 nss-ldapd (which resides in nss-ldapd/nss). You will not need the
53 nslcd daemon; this overlay replaces that part. You should already
54 be familiar with the [RFC2307] and [RFC2307bis] schema to use this
57 for more information on the schema and which features are supported.
59 You will also need to include the nis.schema in your slapd configuration
60 for RFC2307 support. If you wish to use RFC2307bis you will need a slightly
61 different schema. You will also need the ldapns.schema for PAM authorization
66 in the appropriate services in
68 in order for these NSS features to take effect. Likewise, you must
71 for the authenticate, account, session, and password services in
75 for these PAM features to take effect.
79 This directive adds the nssov overlay to the current backend.
81 .B nssov-ssd <service> <url>
82 This directive configures a Service Search Descriptor (SSD) for each NSS
83 service that will be used. The <service> may be one of
99 and the <url> must be of the form
102 .B ldap:///[<basedn>][??[<scope>][?<filter>]]
106 will default to the first suffix of the current database.
109 defaults to "subtree". The default
111 depends on which service is being used.
113 .B nssov-map <service> <orig> <new>
114 If the local database is actually a proxy to a foreign LDAP server, some
115 mapping of schema may be needed. This directive allows some simple attribute
116 substitutions to be performed. See the
118 for the original attribute names used in this code.
120 .B nssov-pam <option> [...]
121 This directive determines a number of PAM behaviors. Multiple options may
122 be used at once, and available levels are:
128 check host attribute in user entry for authorization
131 check authorizedService attribute in user entry for authorization
134 check that user is a member of specific group for authorization
137 check authorizedService attribute in host entry for authorization
140 use authz-regexp mapping to map uid to LDAP DN
143 use NSS passwd SSD to map uid to LDAP DN
152 options duplicates the original pam_ldap authorization behavior.
154 The recommended approach is to use
156 instead. In this case, ipHost entries must be created for all hosts
157 being managed, and they must also have the authorizedServiceObject
158 class to allow authorizedService attributes to be used. Also the
159 NSS host SSD must be configured so that ipHost entries can be found.
160 Authorization is checked by performing an LDAP Compare operation
161 looking for the PAM service name in the authorizedService attribute.
163 ACLs should be set to grant or deny
165 privilege to the appropriate users or groups as desired.
169 option is set then authz-regexp mappings will be used to map the
170 PAM username to an LDAP DN. The authentication DN will be of the
173 .B cn=<service>+uid=<user>,cn=<hostname>,cn=pam,cn=auth
176 If no mapping is found for this authentication DN, then this
177 mapping will be ignored.
181 option is set then the NSS passwd SSD will be used to map the
182 PAM username to an LDAP DN. The passwd SSD must have already been
183 configured for this mapping to succeed.
185 If neither the authz2dn nor the uid2dn mapping succeeds, the module
186 will return a PAM_USER_UNKNOWN failure code. If both options are set,
187 the authz mapping is attempted first; if it succeeds the uid2dn mapping
195 .B nssov-pam-defhost <hostname>
196 Specify a default hostname to check if an ipHost entry for the current
197 hostname cannot be found. This setting is only relevant if the
201 .B nssov-pam-group-dn <DN>
202 Specify the DN of an LDAP group to check for authorization. The LDAP user
203 must be a member of this group for the login to be allowed. There is no
204 default value. This setting is only relevant if the
208 .B nssov-pam-group-ad <attribute>
209 Specify the attribute to use for group membership checks.
210 There is no default value. This setting is only relevant if the
214 .B nssov-pam-minuid <integer>
215 Specify a minimum uid that is allowed to login. Users with a uidNumber
216 lower than this value will be denied access. The default is zero, which
217 disables this setting.
219 .B nssov-pam-maxuid <integer>
220 Specify a maximum uid that is allowed to login. Users with a uidNumber
221 higher than this value will be denied access. The default is zero, which
222 disables this setting.
224 .B nssov-pam-template-ad <attribute>
225 Specify an attribute to check in a user's entry for a template login name.
226 The template login feature is used by FreeBSD's PAM framework. It can be
227 viewed as a form of proxying, where a user can authenticate with one
228 username/password pair, but is assigned the identity and credentials of
229 the template user. This setting is disabled by default.
231 .B nssov-pam-template <name>
232 Specify a default username to be used if no template attribute is found
233 in the user's entry. The
234 .B nssov-pam-template-ad
235 directive must be configured for this setting to have any effect.
237 .B nssov-pam-session <service>
238 Specify a PAM service name whose sessions will be recorded. For the
239 configured services, logins will be recorded in the
241 operational attribute of the user's entry. The attribute's values are
245 .B <generalizedTime> <host> <service> <tty> (<ruser@rhost>)
248 Upon logout the corresponding value will be deleted. This feature allows
249 a single LDAP Search to be used to check which users are logged in across
250 all the hosts of a network. The rootdn of the database is used to perform
251 the updates of the loginStatus attribute, so a rootdn must already be
252 configured for this feature to work. By default no services are configured.
254 The PAM functions support LDAP Password Policy as well. If the password
255 policy overlay is in use (see
256 .BR slapo-ppolicy (5)),
258 information (e.g. password expiration, password quality, etc.)
259 may be returned to the PAM client as a result of authentication,
260 account management, and password modification requests.
262 The overlay also supports dynamic configuration in cn=config. An example
263 of the config entry is
267 dn: olcOverlay={0}nssov,ocDatabase={1}hdb,cn=config
268 objectClass: olcOverlayConfig
269 objectClass: olcNssOvConfig
271 olcNssSsd: passwd ldap:///ou=users,dc=example,dc=com??one
272 olcNssMap: passwd uid accountName
273 olcNssPam: hostservice uid2dn
274 olcNssPamDefHost: defaulthost
276 olcNssPamMaxUid: 32000
277 olcNssPamSession: login
278 olcNssPamSession: sshd
282 which enables the passwd service, and uses the accountName attribute to
283 fetch what is usually retrieved from the uid attribute. It also enables
284 some PAM authorization controls, and specifies that the PAM
288 services should have their logins recorded.
292 default slapd configuration file
295 .BR slapd\-config (5),
297 .BR slapo\-pcache (5),
298 .BR slapo\-ppolicy (5),
301 Howard Chu, inspired by nss-ldapd by Arthur de Jong and pam_ldap by Luke Howard