.TH SLAPD-RELAY 5 "RELEASEDATE" "OpenLDAP LDVERSION"
+.\" Copyright 1998-2011 The OpenLDAP Foundation All Rights Reserved.
+.\" Copying restrictions apply. See COPYRIGHT/LICENSE.
+.\" $OpenLDAP$
.SH NAME
-slapd-relay \- relay backend to slapd
+slapd\-relay \- relay backend to slapd
.SH SYNOPSIS
ETCDIR/slapd.conf
.SH DESCRIPTION
instance into a virtual naming context, with attributeType
and objectClass manipulation, if required.
It requires the
-.B rwm
-.BR overlay .
+.BR slapo\-rwm (5)
+overlay.
.LP
This backend and the above mentioned overlay are experimental.
.SH CONFIGURATION
.BR slapd.conf (5)
manual page; only the
.B suffix
-directive is required by the
+directive is allowed by the
.I relay
backend.
.TP
-.B relay <real naming context> [massage]
+.B relay <real naming context>
The naming context of the database that is presented
under a virtual naming context.
The presence of this directive implies that one specific database,
i.e. the one serving the
.BR "real naming context" ,
will be presented under a virtual naming context.
-This directive automatically instantiates the
-.IR "rwm overlay" .
-If the optional
-.B massage
-keyword is present, the suffix massaging is automatically
-configured as well; otherwise, specific massaging instructions
-are required by means of the
-.I rewrite
-directives described in
-.BR slapo-rwm (5).
+
+.SH MASSAGING
+The
+.B relay
+database does not automatically rewrite the naming context
+of requests and responses.
+For this purpose, the
+.BR slapo\-rwm (5)
+overlay must be explicitly instantiated, and configured
+as appropriate.
+Usually, the
+.B rwm\-suffixmassage
+directive suffices if only naming context rewriting is required.
.SH ACCESS RULES
One important issue is that access rules are based on the identity
that issued the operation.
After massaging from the virtual to the real naming context, the
-frontend sees the operation as performed by the identty in the
+frontend sees the operation as performed by the identity in the
real naming context.
Moreover, since
-.B back-relay
+.B back\-relay
bypasses the real database frontend operations by short-circuiting
-operations thru the internal backend API, the original database
+operations through the internal backend API, the original database
access rules do not apply but in selected cases, i.e. when the
backend itself applies access control.
As a consequence, the instances of the relay database must provide
databases based on details of the virtual naming context,
e.g. groups on one database and persons on another.
.LP
-.SH Caveats
-The
-.B rwm overlay
-is experimental.
-.LP
.SH EXAMPLES
To implement a plain virtual naming context mapping
that refers to a single database, use
.LP
.nf
- database relay
- suffix "dc=virtual,dc=naming,dc=context"
- relay "dc=real,dc=naming,dc=context" massage
+ database relay
+ suffix "dc=virtual,dc=naming,dc=context"
+ relay "dc=real,dc=naming,dc=context"
+ overlay rwm
+ rwm\-suffixmassage "dc=real,dc=naming,dc=context"
.fi
.LP
To implement a plain virtual naming context mapping
that looks up the real naming context for each operation, use
.LP
.nf
- database relay
- suffix "dc=virtual,dc=naming,dc=context"
- overlay rwm
- suffixmassage "dc=virtual,dc=naming,dc=context"
- "dc=real,dc=naming,dc=context"
+ database relay
+ suffix "dc=virtual,dc=naming,dc=context"
+ overlay rwm
+ rwm\-suffixmassage "dc=real,dc=naming,dc=context"
.fi
.LP
This is useful, for instance, to relay different databases that
back from the real to the virtual naming context, use
.LP
.nf
- database relay
- suffix "dc=virtual,dc=naming,dc=context"
- relay "dc=real,dc=naming,dc=context"
- rewriteEngine on
- rewriteContext default
- rewriteRule "dc=virtual,dc=naming,dc=context"
- "dc=real,dc=naming,dc=context" ":@"
- rewriteContext searchFilter
- rewriteContext searchEntryDN
- rewriteContext searchAttrDN
- rewriteContext matchedDN
+ database relay
+ suffix "dc=virtual,dc=naming,dc=context"
+ relay "dc=real,dc=naming,dc=context"
+ overlay rwm
+ rwm\-rewriteEngine on
+ rwm\-rewriteContext default
+ rwm\-rewriteRule "dc=virtual,dc=naming,dc=context"
+ "dc=real,dc=naming,dc=context" ":@"
+ rwm\-rewriteContext searchFilter
+ rwm\-rewriteContext searchEntryDN
+ rwm\-rewriteContext searchAttrDN
+ rwm\-rewriteContext matchedDN
.fi
.LP
-Note that the virtual database is bound to a single real database,
-so the
-.B rwm overlay
-is automatically instantiated, but the rewrite rules
-are written explicitly to map all the virtual to real
-naming context data flow, but none of the real to virtual.
+Note that the
+.BR slapo\-rwm (5)
+overlay is instantiated, but the rewrite rules are written explicitly,
+rather than automatically as with the
+.B rwm\-suffixmassage
+statement, to map all the virtual to real naming context data flow,
+but none of the real to virtual.
.LP
Access rules:
.LP
.nf
- database bdb
- suffix "dc=example,dc=com"
+ database bdb
+ suffix "dc=example,dc=com"
# skip...
access to dn.subtree="dc=example,dc=com"
by dn.exact="cn=Supervisor,dc=example,dc=com" write
by * read
- database relay
- suffix "o=Example,c=US"
- relay "dc=example,dc=com" massage
+ database relay
+ suffix "o=Example,c=US"
+ relay "dc=example,dc=com"
+ overlay rwm
+ rwm\-suffixmassage "dc=example,dc=com"
# skip ...
access to dn.subtree="o=Example,c=US"
by dn.exact="cn=Supervisor,dc=example,dc=com" write
and in the
.BR "virtual naming context" ,
respectively.
+.SH ACCESS CONTROL
+The
+.B relay
+backend does not honor any of the access control semantics described in
+.BR slapd.access (5);
+all access control is delegated to the relayed database(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 FILES
.TP
ETCDIR/slapd.conf
default slapd configuration file
.SH SEE ALSO
.BR slapd.conf (5),
-.BR slapo-rwm (5),
+.BR slapd\-config (5),
+.BR slapo\-rwm (5),
.BR slapd (8).
projects / openldap / blobdiff