1 /* noopsrch.c - LDAP Control that counts entries a search would return */
2 /* $OpenLDAP$ */
3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
4  *
5  * Copyright 2010-2021 The OpenLDAP Foundation.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted only as authorized by the OpenLDAP
10  * Public License.
11  *
12  * A copy of this license is available in the file LICENSE in the
13  * top-level directory of the distribution or, alternatively, at
14  * <http://www.OpenLDAP.org/license.html>.
15  */
16 /* ACKNOWLEDGEMENTS:
17  * This work was initially developed by Pierangelo Masarati for inclusion
18  * in OpenLDAP Software.
19  */
20 
21 #include "portable.h"
22 
23 /* define SLAPD_OVER_NOOPSRCH=2 to build as run-time loadable module */
24 #ifdef SLAPD_OVER_NOOPSRCH
25 
26 /*
27  * Control OID
28  */
29 #define	LDAP_CONTROL_X_NOOPSRCH		"1.3.6.1.4.1.4203.666.5.18"
30 
31 #include "slap.h"
32 #include "ac/string.h"
33 
34 #define o_noopsrch			o_ctrlflag[noopsrch_cid]
35 #define o_ctrlnoopsrch		o_controls[noopsrch_cid]
36 
37 static int noopsrch_cid;
38 static slap_overinst noopsrch;
39 
40 static int
noopsrch_parseCtrl(Operation * op,SlapReply * rs,LDAPControl * ctrl)41 noopsrch_parseCtrl (
42 	Operation *op,
43 	SlapReply *rs,
44 	LDAPControl *ctrl )
45 {
46 	if ( op->o_noopsrch != SLAP_CONTROL_NONE ) {
47 		rs->sr_text = "No-op Search control specified multiple times";
48 		return LDAP_PROTOCOL_ERROR;
49 	}
50 
51 	if ( !BER_BVISNULL( &ctrl->ldctl_value ) ) {
52 		rs->sr_text = "No-op Search control value is present";
53 		return LDAP_PROTOCOL_ERROR;
54 	}
55 
56 	op->o_ctrlnoopsrch = (void *)NULL;
57 
58 	op->o_noopsrch = ctrl->ldctl_iscritical
59 		? SLAP_CONTROL_CRITICAL
60 		: SLAP_CONTROL_NONCRITICAL;
61 
62 	rs->sr_err = LDAP_SUCCESS;
63 
64 	return rs->sr_err;
65 }
66 
67 int dummy;
68 
69 typedef struct noopsrch_cb_t {
70 	slap_overinst	*nc_on;
71 	ber_int_t		nc_nentries;
72 	ber_int_t		nc_nsearchref;
73 	AttributeName	*nc_save_attrs;
74 	int				*nc_pdummy;
75 	int				nc_save_slimit;
76 } noopsrch_cb_t;
77 
78 static int
noopsrch_response(Operation * op,SlapReply * rs)79 noopsrch_response( Operation *op, SlapReply *rs )
80 {
81 	noopsrch_cb_t		*nc = (noopsrch_cb_t *)op->o_callback->sc_private;
82 
83 	/* if the control is global, limits are not computed yet  */
84 	if ( nc->nc_pdummy == &dummy ) {
85 		nc->nc_save_slimit = op->ors_slimit;
86 		op->ors_slimit = SLAP_NO_LIMIT;
87 		nc->nc_pdummy = NULL;
88 	}
89 
90 	if ( rs->sr_type == REP_SEARCH ) {
91 		nc->nc_nentries++;
92 #ifdef NOOPSRCH_DEBUG
93 		Debug( LDAP_DEBUG_TRACE, "noopsrch_response(REP_SEARCH): nentries=%d\n", nc->nc_nentries, 0, 0 );
94 #endif
95 		return 0;
96 
97 	} else if ( rs->sr_type == REP_SEARCHREF ) {
98 		nc->nc_nsearchref++;
99 		return 0;
100 
101 	} else if ( rs->sr_type == REP_RESULT ) {
102 		BerElementBuffer	berbuf;
103 		BerElement			*ber = (BerElement *) &berbuf;
104 		struct berval		ctrlval;
105 		LDAPControl			*ctrl, *ctrlsp[2];
106 		int					rc = rs->sr_err;
107 
108 		if ( nc->nc_save_slimit >= 0 && nc->nc_nentries >= nc->nc_save_slimit ) {
109 			rc = LDAP_SIZELIMIT_EXCEEDED;
110 		}
111 
112 #ifdef NOOPSRCH_DEBUG
113 		Debug( LDAP_DEBUG_TRACE, "noopsrch_response(REP_RESULT): err=%d nentries=%d nref=%d\n", rc, nc->nc_nentries, nc->nc_nsearchref );
114 #endif
115 
116 		ber_init2( ber, NULL, LBER_USE_DER );
117 
118 		ber_printf( ber, "{iii}", rc, nc->nc_nentries, nc->nc_nsearchref );
119 		if ( ber_flatten2( ber, &ctrlval, 0 ) == -1 ) {
120 			ber_free_buf( ber );
121 			if ( op->o_noopsrch == SLAP_CONTROL_CRITICAL ) {
122 				return LDAP_CONSTRAINT_VIOLATION;
123 			}
124 			return SLAP_CB_CONTINUE;
125 		}
126 
127 		ctrl = op->o_tmpcalloc( 1,
128 			sizeof( LDAPControl ) + ctrlval.bv_len + 1,
129 			op->o_tmpmemctx );
130 		ctrl->ldctl_value.bv_val = (char *)&ctrl[ 1 ];
131 		ctrl->ldctl_oid = LDAP_CONTROL_X_NOOPSRCH;
132 		ctrl->ldctl_iscritical = 0;
133 		ctrl->ldctl_value.bv_len = ctrlval.bv_len;
134 		AC_MEMCPY( ctrl->ldctl_value.bv_val, ctrlval.bv_val, ctrlval.bv_len );
135 		ctrl->ldctl_value.bv_val[ ctrl->ldctl_value.bv_len ] = '\0';
136 
137 		ber_free_buf( ber );
138 
139 		ctrlsp[0] = ctrl;
140 		ctrlsp[1] = NULL;
141 		slap_add_ctrls( op, rs, ctrlsp );
142 	}
143 	return SLAP_CB_CONTINUE;
144 }
145 
146 static int
noopsrch_cleanup(Operation * op,SlapReply * rs)147 noopsrch_cleanup( Operation *op, SlapReply *rs )
148 {
149 	if ( rs->sr_type == REP_RESULT || rs->sr_err == SLAPD_ABANDON ) {
150 		noopsrch_cb_t		*nc = (noopsrch_cb_t *)op->o_callback->sc_private;
151 		op->ors_attrs = nc->nc_save_attrs;
152 		if ( nc->nc_pdummy == NULL ) {
153 			op->ors_slimit = nc->nc_save_slimit;
154 		}
155 
156 		op->o_tmpfree( op->o_callback, op->o_tmpmemctx );
157 		op->o_callback = NULL;
158 	}
159 
160 	return SLAP_CB_CONTINUE;
161 }
162 
163 static int
noopsrch_op_search(Operation * op,SlapReply * rs)164 noopsrch_op_search( Operation *op, SlapReply *rs )
165 {
166 	if ( op->o_noopsrch != SLAP_CONTROL_NONE ) {
167 		slap_callback *sc;
168 		noopsrch_cb_t *nc;
169 
170 		sc = op->o_tmpcalloc( 1, sizeof( slap_callback ) + sizeof( noopsrch_cb_t ), op->o_tmpmemctx );
171 
172 		nc = (noopsrch_cb_t *)&sc[ 1 ];
173 		nc->nc_on = (slap_overinst *)op->o_bd->bd_info;
174 		nc->nc_nentries = 0;
175 		nc->nc_nsearchref = 0;
176 		nc->nc_save_attrs = op->ors_attrs;
177 		nc->nc_pdummy = &dummy;
178 
179 		sc->sc_response = noopsrch_response;
180 		sc->sc_cleanup = noopsrch_cleanup;
181 		sc->sc_private = (void *)nc;
182 
183 		op->ors_attrs = slap_anlist_no_attrs;
184 
185 		sc->sc_next = op->o_callback->sc_next;
186                 op->o_callback->sc_next = sc;
187 	}
188 
189 	return SLAP_CB_CONTINUE;
190 }
191 
192 static int noopsrch_cnt;
193 
194 static int
noopsrch_db_init(BackendDB * be,ConfigReply * cr)195 noopsrch_db_init( BackendDB *be, ConfigReply *cr)
196 {
197 	if ( noopsrch_cnt++ == 0 ) {
198 		int rc;
199 
200 		rc = register_supported_control( LDAP_CONTROL_X_NOOPSRCH,
201 			SLAP_CTRL_SEARCH | SLAP_CTRL_GLOBAL_SEARCH, NULL,
202 			noopsrch_parseCtrl, &noopsrch_cid );
203 		if ( rc != LDAP_SUCCESS ) {
204 			Debug( LDAP_DEBUG_ANY,
205 				"noopsrch_initialize: Failed to register control '%s' (%d)\n",
206 				LDAP_CONTROL_X_NOOPSRCH, rc, 0 );
207 			return rc;
208 		}
209 	}
210 
211 	return LDAP_SUCCESS;
212 }
213 
214 static int
noopsrch_db_destroy(BackendDB * be,ConfigReply * cr)215 noopsrch_db_destroy( BackendDB *be, ConfigReply *cr )
216 {
217 	assert( noopsrch_cnt > 0 );
218 
219 #ifdef SLAP_CONFIG_DELETE
220 	overlay_unregister_control( be, LDAP_CONTROL_X_NOOPSRCH );
221 	if ( --noopsrch_cnt == 0 ) {
222 		unregister_supported_control( LDAP_CONTROL_X_NOOPSRCH );
223 	}
224 
225 #endif /* SLAP_CONFIG_DELETE */
226 
227 	return 0;
228 }
229 
230 #if SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC
231 static
232 #endif /* SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC */
233 int
noopsrch_initialize(void)234 noopsrch_initialize( void )
235 {
236 
237 	noopsrch.on_bi.bi_type = "noopsrch";
238 
239 	noopsrch.on_bi.bi_db_init = noopsrch_db_init;
240 	noopsrch.on_bi.bi_db_destroy = noopsrch_db_destroy;
241 	noopsrch.on_bi.bi_op_search = noopsrch_op_search;
242 
243 	return overlay_register( &noopsrch );
244 }
245 
246 #if SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC
247 int
init_module(int argc,char * argv[])248 init_module( int argc, char *argv[] )
249 {
250 	return noopsrch_initialize();
251 }
252 #endif /* SLAPD_OVER_NOOPSRCH == SLAPD_MOD_DYNAMIC */
253 
254 #endif /* SLAPD_OVER_NOOPSRCH */
255