openldap/servers/slapd/back-meta/candidates.c
2003-11-27 06:35:14 +00:00

271 lines
7.0 KiB
C

/* $OpenLDAP$ */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
*
* Copyright 1999-2003 The OpenLDAP Foundation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted only as authorized by the OpenLDAP
* Public License.
*
* A copy of this license is available in the file LICENSE in the
* top-level directory of the distribution or, alternatively, at
* <http://www.OpenLDAP.org/license.html>.
*/
/* ACKNOWLEDGEMENTS:
* This work was initially developed by the Howard Chu for inclusion
* in OpenLDAP Software and subsequently enhanced by Pierangelo
* Masarati.
*/
/* This is an altered version */
/*
* Copyright 2001, Pierangelo Masarati, All rights reserved. <ando@sys-net.it>
*
* This work has been developed to fulfill the requirements
* of SysNet s.n.c. <http:www.sys-net.it> and it has been donated
* to the OpenLDAP Foundation in the hope that it may be useful
* to the Open Source community, but WITHOUT ANY WARRANTY.
*
* Permission is granted to anyone to use this software for any purpose
* on any computer system, and to alter it and redistribute it, subject
* to the following restrictions:
*
* 1. The author and SysNet s.n.c. are not responsible for the consequences
* of use of this software, no matter how awful, even if they arise from
* flaws in it.
*
* 2. The origin of this software must not be misrepresented, either by
* explicit claim or by omission. Since few users ever read sources,
* credits should appear in the documentation.
*
* 3. Altered versions must be plainly marked as such, and must not be
* misrepresented as being the original software. Since few users
* ever read sources, credits should appear in the documentation.
* SysNet s.n.c. cannot be responsible for the consequences of the
* alterations.
*
* 4. This notice may not be removed or altered.
*
*
* This software is based on the backend back-ldap, implemented
* by Howard Chu <hyc@highlandsun.com>, and modified by Mark Valence
* <kurash@sassafras.com>, Pierangelo Masarati <ando@sys-net.it> and other
* contributors. The contribution of the original software to the present
* implementation is acknowledged in this copyright statement.
*
* A special acknowledgement goes to Howard for the overall architecture
* (and for borrowing large pieces of code), and to Mark, who implemented
* from scratch the attribute/objectclass mapping.
*
* The original copyright statement follows.
*
* Copyright 1999, Howard Chu, All rights reserved. <hyc@highlandsun.com>
*
* Permission is granted to anyone to use this software for any purpose
* on any computer system, and to alter it and redistribute it, subject
* to the following restrictions:
*
* 1. The author is not responsible for the consequences of use of this
* software, no matter how awful, even if they arise from flaws in it.
*
* 2. The origin of this software must not be misrepresented, either by
* explicit claim or by omission. Since few users ever read sources,
* credits should appear in the documentation.
*
* 3. Altered versions must be plainly marked as such, and must not be
* misrepresented as being the original software. Since few users
* ever read sources, credits should appear in the
* documentation.
*
* 4. This notice may not be removed or altered.
*
*/
#include "portable.h"
#include <stdio.h>
#include "slap.h"
#include "../back-ldap/back-ldap.h"
#include "back-meta.h"
/*
* The meta-directory has one suffix, called <suffix>.
* It handles a pool of target servers, each with a branch suffix
* of the form <branch X>,<suffix>
*
* When the meta-directory receives a request with a dn that belongs
* to a branch, the corresponding target is invoked. When the dn
* does not belong to a specific branch, all the targets that
* are compatible with the dn are selected as candidates, and
* the request is spawned to all the candidate targets
*
* A request is characterized by a dn. The following cases are handled:
* - the dn is the suffix: <dn> == <suffix>,
* all the targets are candidates (search ...)
* - the dn is a branch suffix: <dn> == <branch X>,<suffix>, or
* - the dn is a subtree of a branch suffix:
* <dn> == <rdn>,<branch X>,<suffix>,
* the target is the only candidate.
*
* A possible extension will include the handling of multiple suffixes
*/
/*
* returns 1 if suffix is candidate for dn, otherwise 0
*
* Note: this function should never be called if dn is the <suffix>.
*/
int
meta_back_is_candidate(
struct berval *nsuffix,
struct berval *ndn
)
{
if ( dnIsSuffix( nsuffix, ndn ) || dnIsSuffix( ndn, nsuffix ) ) {
/*
* suffix longer than dn
*/
return META_CANDIDATE;
}
return META_NOT_CANDIDATE;
}
/*
* meta_back_count_candidates
*
* returns a count of the possible candidate targets
* Note: dn MUST be normalized
*/
int
meta_back_count_candidates(
struct metainfo *li,
struct berval *ndn
)
{
int i, cnt = 0;
/*
* I know assertions should not check run-time values;
* at present I didn't find a place for such checks
* after config.c
*/
assert( li->targets != NULL );
assert( li->ntargets != 0 );
for ( i = 0; i < li->ntargets; ++i ) {
if ( meta_back_is_candidate( &li->targets[ i ]->suffix, ndn ) ) {
++cnt;
}
}
return cnt;
}
/*
* meta_back_is_candidate_unique
*
* checks whether a candidate is unique
* Note: dn MUST be normalized
*/
int
meta_back_is_candidate_unique(
struct metainfo *li,
struct berval *ndn
)
{
return ( meta_back_count_candidates( li, ndn ) == 1 );
}
/*
* meta_back_select_unique_candidate
*
* returns the index of the candidate in case it is unique, otherwise -1
* Note: dn MUST be normalized.
* Note: if defined, the default candidate is returned in case of no match.
*/
int
meta_back_select_unique_candidate(
struct metainfo *li,
struct berval *ndn
)
{
int i;
switch ( meta_back_count_candidates( li, ndn ) ) {
case 1:
break;
case 0:
default:
return ( li->defaulttarget == META_DEFAULT_TARGET_NONE
? -1 : li->defaulttarget );
}
for ( i = 0; i < li->ntargets; ++i ) {
if ( meta_back_is_candidate( &li->targets[ i ]->suffix, ndn ) ) {
return i;
}
}
return -1;
}
/*
* meta_clear_unused_candidates
*
* clears all candidates except candidate
*/
int
meta_clear_unused_candidates(
struct metainfo *li,
struct metaconn *lc,
int candidate,
int reallyclean
)
{
int i;
for ( i = 0; i < li->ntargets; ++i ) {
if ( i == candidate ) {
continue;
}
meta_clear_one_candidate( &lc->conns[ i ], reallyclean );
}
return 0;
}
/*
* meta_clear_one_candidate
*
* clears the selected candidate
*/
int
meta_clear_one_candidate(
struct metasingleconn *lsc,
int reallyclean
)
{
lsc->candidate = META_NOT_CANDIDATE;
if ( !reallyclean ) {
return 0;
}
if ( lsc->ld ) {
ldap_unbind( lsc->ld );
lsc->ld = NULL;
}
if ( lsc->bound_dn.bv_val != NULL ) {
ber_memfree( lsc->bound_dn.bv_val );
lsc->bound_dn.bv_val = NULL;
lsc->bound_dn.bv_len = 0;
}
return 0;
}