slapd-ldap.5

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\fBoverride,{prescriptive|non-prescriptive}\fP

When the 
.B override
flag is used, identity assertion takes place even when the database
is authorizing for the identity of the client, i.e. after binding
with the provided identity, and thus authenticating it, the proxy
performs the identity assertion using the configured identity and
authentication method.

When the
.B prescriptive
flag is used (the default), operations fail with
\fIinappropriateAuthentication\fP
for those identities whose assertion is not allowed by the
.B idassert-authzFrom
patterns.
If the 
.B non-prescriptive
flag is used, operations are performed anonymously for those identities 
whose assertion is not allowed by the
.B idassert-authzFrom
patterns.

This directive obsoletes
.BR idassert-authcDN ,
.BR idassert-passwd ,
.BR idassert-mode ,
and
.BR idassert-method .
.RE

.TP
.B idle-timeout <time>
This directive causes a cached connection to be dropped an recreated
after it has been idle for the specified time.

.TP
.B network-timeout <time>
Sets the network timeout value after which
.BR poll (2)/ select (2) 
following a 
.BR connect (2) 
returns in case of no activity.
The value is in seconds, and it can be specified as for
.BR idle-timeout .

.TP
.B protocol\-version {0,2,3}
This directive indicates what protocol version must be used to contact
the remote server.
If set to 0 (the default), the proxy uses the same protocol version 
used by the client, otherwise the requested protocol is used.
The proxy returns \fIunwillingToPerform\fP if an operation that is 
incompatible with the requested protocol is attempted.

.TP
.B proxy\-whoami {NO|yes}
Turns on proxying of the WhoAmI extended operation. If this option is
given, back-ldap will replace slapd's original WhoAmI routine with its
own. On slapd sessions that were authenticated by back-ldap, the WhoAmI
request will be forwarded to the remote LDAP server. Other sessions will
be handled by the local slapd, as before. This option is mainly useful
in conjunction with Proxy Authorization.

.TP
.B rebind-as-user {NO|yes}
If this option is given, the client's bind credentials are remembered
for rebinds, when trying to re-establish a broken connection,
or when chasing a referral, if 
.B chase-referrals
is set to
.IR yes .

.TP
.B t-f-support {NO|yes|discover}
enable if the remote server supports absolute filters
(see \fIdraft-zeilenga-ldap-t-f\fP for details).
If set to
.BR discover ,
support is detected by reading the remote server's root DSE.

.TP
.B timeout [{add|delete|modify|modrdn}=]<val> [...]
This directive allows to set per-operation timeouts.
If no operation is specified, it affects all.
Currently, only write operations are addressed, because searches
can already be limited by means of the
.B limits
directive (see 
.BR slapd.conf (5)
for details), and other operations are not supposed to incur into the
need for timeouts.
Note: if the timelimit is exceeded, the operation is abandoned;
the protocol does not provide any means to rollback the operation,
so the client will not know if the operation eventually succeeded or not.

.TP
.B tls {[try-]start|[try-]propagate}
execute the StartTLS extended operation when the connection is initialized;
only works if the URI directive protocol scheme is not \fBldaps://\fP.
\fBpropagate\fP issues the StartTLS operation only if the original
connection did.
The \fBtry-\fP prefix instructs the proxy to continue operations
if the StartTLS operation failed; its use is highly deprecated.

.SH BACKWARD COMPATIBILITY
The LDAP backend has been heavily reworked between releases 2.2 and 2.3;
as a side-effect, some of the traditional directives have been
deprecated and should be no longer used, as they might disappear
in future releases.

.TP
.B server <hostname[:port]>
this directive is no longer supported.  Use the 
.B uri
directive as described above.

.TP
.B acl-authcDN "<administrative DN for access control purposes>"
DN which is used to query the target server for acl checking; it
is supposed to have read access on the target server to attributes used
on the proxy for acl checking.
There is no risk of giving away such values; they are only used to
check permissions.
.B The acl-authcDN identity is by no means implicitly used by the proxy 
.B when the client connects anonymously.
See the
.B idassert-*
feature instead.
This directive is obsoleted by the
.B binddn
arg of
.B acl-bind
when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.

.TP
.B acl-passwd <password>
Password used with the above
.B acl-authcDN
directive.
This directive is obsoleted by the
.B binddn
arg of
.B acl-bind
when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.

.TP
.B idassert-authcDN "<administrative DN for proxyAuthz purposes>"
DN which is used to propagate the client's identity to the target
by means of the proxyAuthz control when the client does not
belong to the DIT fragment that is being proxied by back-ldap.
This directive is obsoleted by the
.B binddn
arg of
.BR idassert-bind
when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.

.TP
.B idassert-passwd <password>
Password used with the
.B idassert-authcDN
above.
This directive is obsoleted by the
.B crendentials
of
.B idassert-bind
when \fIbindmethod\fP=\fBsimple\fP, and will be dismissed in the future.

.TP
.B idassert-mode <mode> [<flags>]
defines what type of
.I identity assertion
is used.
This directive is obsoleted by the
.B mode
arg of 
.BR idassert-bind ,
and will be dismissed in the future.

.TP
.B idassert-method <method> [<saslargs>]
This directive is obsoleted by the
.B bindmethod
arg of
.BR idassert-bind ,
and will be dismissed in the future.

.TP
.B suffixmassage, map, rewrite*
These directives are no longer supported by back-ldap; their 
functionality is now delegated to the
.B rwm
overlay.  Essentially, add a statement

.B overlay rwm

first, and prefix all rewrite/map statements with
.B rwm-
to obtain the original behavior.
See
.BR slapo-rwm (5)
for details.
.\" However, to ease update from existing configurations, back-ldap still 
.\" recognizes them and automatically instantiates the
.\" .B rwm
.\" overlay if available and not instantiated yet.
.\" This behavior may change in the future.

.SH ACCESS CONTROL
The
.B ldap
backend does not honor all ACL semantics as described in
.BR slapd.access (5).
In general, access checking is delegated to the remote server(s).
Only
.B read (=r)
access to the
.B entry
pseudo-attribute and to the other attribute values of the entries
returned by the
.B search
operation is honored, which is performed by the frontend.

.SH OVERLAYS
The LDAP backend provides basic proxying functionalities to many overlays.
The 
.B chain
overlay, described in
.BR slapo\-chain (5),
and the
.B translucent
overlay, described in
.BR slapo\-translucent (5),
deserve a special mention.

Conversely, there are many overlays that are best used in conjunction
with the LDAP backend.
The
.B proxycache 
overlay allows caching of LDAP search requests (queries) 
in a local database.
See 
.BR slapo\-pcache (5)
for details.
The
.B rwm
overlay provides DN rewrite and attribute/objectClass mapping
capabilities to the underlying database.
See 
.BR slapo\-rwm (5)
for details.

.SH FILES
.TP
ETCDIR/slapd.conf
default slapd configuration file
.SH SEE ALSO
.BR slapd.conf (5),
.BR slapd\-meta (5),
.BR slapo\-chain (5),
.BR slapo\-pcache (5),
.BR slapo\-rwm (5),
.BR slapo\-translucent (5),
.BR slapd (8),
.BR ldap (3).
.SH AUTHOR
Howard Chu, with enhancements by Pierangelo Masarati