1 /*        $NetBSD: ctxcsn.c,v 1.3 2021/08/14 16:14:58 christos Exp $  */
2 
3 /* ctxcsn.c -- Context CSN Management Routines */
4 /* $OpenLDAP$ */
5 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
6  *
7  * Copyright 2003-2021 The OpenLDAP Foundation.
8  * Portions Copyright 2003 IBM Corporation.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted only as authorized by the OpenLDAP
13  * Public License.
14  *
15  * A copy of this license is available in the file LICENSE in the
16  * top-level directory of the distribution or, alternatively, at
17  * <http://www.OpenLDAP.org/license.html>.
18  */
19 
20 #include <sys/cdefs.h>
21 __RCSID("$NetBSD: ctxcsn.c,v 1.3 2021/08/14 16:14:58 christos Exp $");
22 
23 #include "portable.h"
24 
25 #include <stdio.h>
26 
27 #include <ac/string.h>
28 #include <ac/socket.h>
29 
30 #include "lutil.h"
31 #include "slap.h"
32 #include "lutil_ldap.h"
33 
34 const struct berval slap_ldapsync_bv = BER_BVC("ldapsync");
35 const struct berval slap_ldapsync_cn_bv = BER_BVC("cn=ldapsync");
36 int slap_serverID;
37 
38 /* maxcsn->bv_val must point to a char buf[LDAP_PVT_CSNSTR_BUFSIZE] */
39 void
slap_get_commit_csn(Operation * op,struct berval * maxcsn,int * foundit)40 slap_get_commit_csn(
41           Operation *op,
42           struct berval *maxcsn,
43           int *foundit
44 )
45 {
46           struct slap_csn_entry *csne, *committed_csne = NULL;
47           BackendDB *be = op->o_bd->bd_self;
48           int sid = -1;
49 
50           if ( maxcsn ) {
51                     assert( maxcsn->bv_val != NULL );
52                     assert( maxcsn->bv_len >= LDAP_PVT_CSNSTR_BUFSIZE );
53           }
54           if ( foundit ) {
55                     *foundit = 0;
56           }
57 
58           if ( !BER_BVISEMPTY( &op->o_csn )) {
59                     sid = slap_parse_csn_sid( &op->o_csn );
60           }
61 
62           ldap_pvt_thread_mutex_lock( &be->be_pcl_mutex );
63 
64           LDAP_TAILQ_FOREACH( csne, be->be_pending_csn_list, ce_csn_link ) {
65                     if ( csne->ce_op == op ) {
66                               csne->ce_state = SLAP_CSN_COMMIT;
67                               if ( foundit ) *foundit = 1;
68                               break;
69                     }
70           }
71 
72           LDAP_TAILQ_FOREACH( csne, be->be_pending_csn_list, ce_csn_link ) {
73                     if ( sid != -1 && sid == csne->ce_sid ) {
74                               if ( csne->ce_state == SLAP_CSN_COMMIT ) committed_csne = csne;
75                               if ( csne->ce_state == SLAP_CSN_PENDING ) break;
76                     }
77           }
78 
79           if ( maxcsn ) {
80                     if ( committed_csne ) {
81                               if ( committed_csne->ce_csn.bv_len < maxcsn->bv_len )
82                                         maxcsn->bv_len = committed_csne->ce_csn.bv_len;
83                               AC_MEMCPY( maxcsn->bv_val, committed_csne->ce_csn.bv_val,
84                                         maxcsn->bv_len+1 );
85                     } else {
86                               maxcsn->bv_len = 0;
87                               maxcsn->bv_val[0] = 0;
88                     }
89           }
90           ldap_pvt_thread_mutex_unlock( &be->be_pcl_mutex );
91 }
92 
93 void
slap_rewind_commit_csn(Operation * op)94 slap_rewind_commit_csn( Operation *op )
95 {
96           struct slap_csn_entry *csne;
97           BackendDB *be = op->o_bd->bd_self;
98 
99           ldap_pvt_thread_mutex_lock( &be->be_pcl_mutex );
100 
101           LDAP_TAILQ_FOREACH( csne, be->be_pending_csn_list, ce_csn_link ) {
102                     if ( csne->ce_op == op ) {
103                               csne->ce_state = SLAP_CSN_PENDING;
104                               break;
105                     }
106           }
107 
108           ldap_pvt_thread_mutex_unlock( &be->be_pcl_mutex );
109 }
110 
111 void
slap_graduate_commit_csn(Operation * op)112 slap_graduate_commit_csn( Operation *op )
113 {
114           struct slap_csn_entry *csne;
115           BackendDB *be;
116 
117           if ( op == NULL ) return;
118           if ( op->o_bd == NULL ) return;
119           be = op->o_bd->bd_self;
120 
121           ldap_pvt_thread_mutex_lock( &be->be_pcl_mutex );
122 
123           LDAP_TAILQ_FOREACH( csne, be->be_pending_csn_list, ce_csn_link ) {
124                     if ( csne->ce_op == op ) {
125                               LDAP_TAILQ_REMOVE( be->be_pending_csn_list,
126                                         csne, ce_csn_link );
127                               Debug( LDAP_DEBUG_SYNC, "slap_graduate_commit_csn: removing %p %s\n",
128                                         csne, csne->ce_csn.bv_val );
129                               if ( op->o_csn.bv_val == csne->ce_csn.bv_val ) {
130                                         BER_BVZERO( &op->o_csn );
131                               }
132                               ch_free( csne->ce_csn.bv_val );
133                               ch_free( csne );
134                               break;
135                     }
136           }
137 
138           ldap_pvt_thread_mutex_unlock( &be->be_pcl_mutex );
139 
140           return;
141 }
142 
143 static struct berval ocbva[] = {
144           BER_BVC("top"),
145           BER_BVC("subentry"),
146           BER_BVC("syncProviderSubentry"),
147           BER_BVNULL
148 };
149 
150 Entry *
slap_create_context_csn_entry(Backend * be,struct berval * context_csn)151 slap_create_context_csn_entry(
152           Backend *be,
153           struct berval *context_csn )
154 {
155           Entry* e;
156 
157           struct berval bv;
158 
159           e = entry_alloc();
160 
161           attr_merge( e, slap_schema.si_ad_objectClass,
162                     ocbva, NULL );
163           attr_merge_one( e, slap_schema.si_ad_structuralObjectClass,
164                     &ocbva[1], NULL );
165           attr_merge_one( e, slap_schema.si_ad_cn,
166                     (struct berval *)&slap_ldapsync_bv, NULL );
167 
168           if ( context_csn ) {
169                     attr_merge_one( e, slap_schema.si_ad_contextCSN,
170                               context_csn, NULL );
171           }
172 
173           BER_BVSTR( &bv, "{}" );
174           attr_merge_one( e, slap_schema.si_ad_subtreeSpecification, &bv, NULL );
175 
176           build_new_dn( &e->e_name, &be->be_nsuffix[0],
177                     (struct berval *)&slap_ldapsync_cn_bv, NULL );
178           ber_dupbv( &e->e_nname, &e->e_name );
179 
180           return e;
181 }
182 
183 void
slap_queue_csn(Operation * op,struct berval * csn)184 slap_queue_csn(
185           Operation *op,
186           struct berval *csn )
187 {
188           struct slap_csn_entry *pending;
189           BackendDB *be = op->o_bd->bd_self;
190 
191           pending = (struct slap_csn_entry *) ch_calloc( 1,
192                               sizeof( struct slap_csn_entry ));
193 
194           Debug( LDAP_DEBUG_SYNC, "slap_queue_csn: queueing %p %s\n", pending, csn->bv_val );
195 
196           ber_dupbv( &pending->ce_csn, csn );
197           ber_bvreplace_x( &op->o_csn, &pending->ce_csn, op->o_tmpmemctx );
198           pending->ce_sid = slap_parse_csn_sid( csn );
199           pending->ce_op = op;
200           pending->ce_state = SLAP_CSN_PENDING;
201 
202           ldap_pvt_thread_mutex_lock( &be->be_pcl_mutex );
203           LDAP_TAILQ_INSERT_TAIL( be->be_pending_csn_list,
204                     pending, ce_csn_link );
205           ldap_pvt_thread_mutex_unlock( &be->be_pcl_mutex );
206 }
207 
208 int
slap_get_csn(Operation * op,struct berval * csn,int manage_ctxcsn)209 slap_get_csn(
210           Operation *op,
211           struct berval *csn,
212           int manage_ctxcsn )
213 {
214           if ( csn == NULL ) return LDAP_OTHER;
215 
216           csn->bv_len = ldap_pvt_csnstr( csn->bv_val, csn->bv_len, slap_serverID, 0 );
217           Debug( LDAP_DEBUG_SYNC, "slap_get_csn: %s generated new csn=%s manage=%d\n",
218                     op->o_log_prefix, csn->bv_val, manage_ctxcsn );
219           if ( manage_ctxcsn )
220                     slap_queue_csn( op, csn );
221 
222           return LDAP_SUCCESS;
223 }
224