1 files changed, 312 insertions, 0 deletions
diff --git a/servers/slapd/back-asyncmeta/compare.c b/servers/slapd/back-asyncmeta/compare.c
new file mode 100644
index 0000000..8f56719
--- /dev/null
+++ b/servers/slapd/back-asyncmeta/compare.c
@@ -0,0 +1,312 @@
+/* compare.c - compare exop handler for back-asyncmeta */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2016-2022 The OpenLDAP Foundation.
+ * Portions Copyright 2016 Symas Corporation.
+ * 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 developed by Symas Corporation
++ * based on back-meta module for inclusion in OpenLDAP Software.
++ * This work was sponsored by Ericsson. */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+#include "slap.h"
+#include "../../../libraries/liblber/lber-int.h"
+#include "../../../libraries/libldap/ldap-int.h"
+#include "../back-ldap/back-ldap.h"
+#include "back-asyncmeta.h"
+
+meta_search_candidate_t
+asyncmeta_back_compare_start(Operation *op,
+			     SlapReply *rs,
+			     a_metaconn_t *mc,
+			     bm_context_t *bc,
+			     int candidate,
+			     int do_lock)
+{
+	a_dncookie	dc;
+	a_metainfo_t	*mi = mc->mc_info;
+	a_metatarget_t	*mt = mi->mi_targets[ candidate ];
+	struct berval	c_attr = op->orc_ava->aa_desc->ad_cname;
+	struct berval	mdn = BER_BVNULL;
+	struct berval	mapped_value = op->orc_ava->aa_value;
+	int rc = 0;
+	LDAPControl	**ctrls = NULL;
+	meta_search_candidate_t retcode = META_SEARCH_CANDIDATE;
+	BerElement *ber = NULL;
+	a_metasingleconn_t	*msc = &mc->mc_conns[ candidate ];
+	SlapReply		*candidates = bc->candidates;
+	ber_int_t	msgid;
+
+	dc.op = op;
+	dc.target = mt;
+	dc.memctx = op->o_tmpmemctx;
+	dc.to_from = MASSAGE_REQ;
+
+	asyncmeta_dn_massage( &dc, &op->o_req_dn, &mdn );
+
+	if ( op->orc_ava->aa_desc->ad_type->sat_syntax == slap_schema.si_syn_distinguishedName )
+		asyncmeta_dn_massage( &dc, &op->orc_ava->aa_value, &mapped_value );
+
+	asyncmeta_set_msc_time(msc);
+	ctrls = op->o_ctrls;
+	if ( asyncmeta_controls_add( op, rs, mc, candidate, bc->is_root,&ctrls ) != LDAP_SUCCESS )
+	{
+		candidates[ candidate ].sr_msgid = META_MSGID_IGNORE;
+		retcode = META_SEARCH_ERR;
+		goto done;
+	}
+	/* someone might have reset the connection */
+	if (!( LDAP_BACK_CONN_ISBOUND( msc )
+	       || LDAP_BACK_CONN_ISANON( msc )) || msc->msc_ld == NULL ) {
+		Debug( asyncmeta_debug, "msc %p not initialized at %s:%d\n", msc, __FILE__, __LINE__ );
+		goto error_unavailable;
+	}
+
+	ber = ldap_build_compare_req( msc->msc_ld, mdn.bv_val, c_attr.bv_val, &mapped_value,
+			ctrls, NULL, &msgid);
+
+	if (!ber) {
+		Debug( asyncmeta_debug, "%s asyncmeta_back_compare_start: Operation encoding failed with errno %d\n",
+		       op->o_log_prefix, msc->msc_ld->ld_errno );
+		rs->sr_err = LDAP_OPERATIONS_ERROR;
+		rs->sr_text = "Failed to encode proxied request";
+		retcode = META_SEARCH_ERR;
+		goto done;
+	}
+
+	if (ber) {
+		struct timeval tv = {0, mt->mt_network_timeout*1000};
+		ber_socket_t s;
+		if (!( LDAP_BACK_CONN_ISBOUND( msc )
+		       || LDAP_BACK_CONN_ISANON( msc )) || msc->msc_ld == NULL ) {
+			Debug( asyncmeta_debug, "msc %p not initialized at %s:%d\n", msc, __FILE__, __LINE__ );
+			goto error_unavailable;
+		}
+
+		ldap_get_option( msc->msc_ld, LDAP_OPT_DESC, &s );
+		if (s < 0) {
+			Debug( asyncmeta_debug, "msc %p not initialized at %s:%d\n", msc, __FILE__, __LINE__ );
+			goto error_unavailable;
+		}
+		rc = ldap_int_poll( msc->msc_ld, s, &tv, 1);
+		if (rc < 0) {
+			Debug( asyncmeta_debug, "msc %p not writable within network timeout %s:%d\n", msc, __FILE__, __LINE__ );
+			if ((msc->msc_result_time + META_BACK_RESULT_INTERVAL) < slap_get_time()) {
+				rc = LDAP_SERVER_DOWN;
+			} else {
+				goto error_unavailable;
+			}
+		} else {
+			candidates[ candidate ].sr_msgid = msgid;
+			rc = ldap_send_initial_request( msc->msc_ld, LDAP_REQ_COMPARE,
+							mdn.bv_val, ber, msgid );
+			if (rc == msgid)
+				rc = LDAP_SUCCESS;
+			else
+				rc = LDAP_SERVER_DOWN;
+			ber = NULL;
+		}
+
+		switch ( rc ) {
+		case LDAP_SUCCESS:
+			retcode = META_SEARCH_CANDIDATE;
+			asyncmeta_set_msc_time(msc);
+			goto done;
+
+		case LDAP_SERVER_DOWN:
+			/* do not lock if called from asyncmeta_handle_bind_result. Also do not reset the connection */
+			if (do_lock > 0) {
+				ldap_pvt_thread_mutex_lock( &mc->mc_om_mutex);
+				asyncmeta_reset_msc(NULL, mc, candidate, 0, __FUNCTION__);
+				ldap_pvt_thread_mutex_unlock( &mc->mc_om_mutex);
+			}
+			/* fall though*/
+		default:
+			Debug( asyncmeta_debug, "msc %p ldap_send_initial_request failed. %s:%d\n", msc, __FILE__, __LINE__ );
+			goto error_unavailable;
+		}
+	}
+
+error_unavailable:
+	if (ber)
+		ber_free(ber, 1);
+	switch (bc->nretries[candidate]) {
+	case -1: /* nretries = forever */
+		retcode = META_SEARCH_NEED_BIND;
+		break;
+	case 0: /* no retries left */
+		candidates[ candidate ].sr_msgid = META_MSGID_IGNORE;
+		rs->sr_err = LDAP_UNAVAILABLE;
+		rs->sr_text = "Unable to send compare request to target";
+		retcode = META_SEARCH_ERR;
+		break;
+	default: /* more retries left - try to rebind and go again */
+		retcode = META_SEARCH_NEED_BIND;
+		bc->nretries[candidate]--;
+		break;
+	}
+done:
+	(void)mi->mi_ldap_extra->controls_free( op, rs, &ctrls );
+
+	if ( op->orc_ava->aa_value.bv_val != mapped_value.bv_val ) {
+		op->o_tmpfree( mapped_value.bv_val, op->o_tmpmemctx );
+	}
+
+	if ( mdn.bv_val != op->o_req_dn.bv_val ) {
+		op->o_tmpfree( mdn.bv_val, op->o_tmpmemctx );
+	}
+
+	Debug( LDAP_DEBUG_TRACE, "%s <<< asyncmeta_back_compare_start[%p]=%d\n", op->o_log_prefix, msc, candidates[candidate].sr_msgid );
+	return retcode;
+}
+
+int
+asyncmeta_back_compare( Operation *op, SlapReply *rs )
+{
+	a_metainfo_t	*mi = ( a_metainfo_t * )op->o_bd->be_private;
+	a_metatarget_t	*mt;
+	a_metaconn_t	*mc;
+	int		rc, candidate = -1;
+	void *thrctx = op->o_threadctx;
+	bm_context_t *bc;
+	SlapReply *candidates;
+	time_t current_time = slap_get_time();
+	int max_pending_ops = (mi->mi_max_pending_ops == 0) ? META_BACK_CFG_MAX_PENDING_OPS : mi->mi_max_pending_ops;
+
+	Debug(LDAP_DEBUG_ARGS, "==> asyncmeta_back_compare: %s\n",
+	      op->o_req_dn.bv_val );
+
+	if (current_time > op->o_time) {
+		Debug( asyncmeta_debug, "==> asyncmeta_back_compare[%s]: o_time:[%ld], current time: [%ld]\n",
+		       op->o_log_prefix, op->o_time, current_time );
+	}
+
+	if ( mi->mi_ntargets == 0 ) {
+		rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
+		rs->sr_text = "No targets are configured for this database";
+		send_ldap_result(op, rs);
+		return rs->sr_err;
+	}
+
+	asyncmeta_new_bm_context(op, rs, &bc, mi->mi_ntargets, mi );
+	if (bc == NULL) {
+		rs->sr_err = LDAP_OTHER;
+		send_ldap_result(op, rs);
+		return rs->sr_err;
+	}
+
+	candidates = bc->candidates;
+	mc = asyncmeta_getconn( op, rs, candidates, &candidate, LDAP_BACK_DONTSEND, 0);
+	if ( !mc || rs->sr_err != LDAP_SUCCESS) {
+		send_ldap_result(op, rs);
+		return rs->sr_err;
+	}
+
+	mt = mi->mi_targets[ candidate ];
+	bc->timeout = mt->mt_timeout[ SLAP_OP_COMPARE ];
+	bc->retrying = LDAP_BACK_RETRYING;
+	bc->sendok = ( LDAP_BACK_SENDRESULT | bc->retrying );
+	bc->stoptime = op->o_time + bc->timeout;
+	bc->bc_active = 1;
+
+	if (mc->pending_ops >= max_pending_ops) {
+		rs->sr_err = LDAP_BUSY;
+		rs->sr_text = "Maximum pending ops limit exceeded";
+		send_ldap_result(op, rs);
+		return rs->sr_err;
+	}
+
+	ldap_pvt_thread_mutex_lock( &mc->mc_om_mutex);
+	rc = asyncmeta_add_message_queue(mc, bc);
+	mc->mc_conns[candidate].msc_active++;
+	ldap_pvt_thread_mutex_unlock( &mc->mc_om_mutex);
+
+	if (rc != LDAP_SUCCESS) {
+		rs->sr_err = LDAP_BUSY;
+		rs->sr_text = "Maximum pending ops limit exceeded";
+		send_ldap_result(op, rs);
+		ldap_pvt_thread_mutex_lock( &mc->mc_om_mutex);
+		mc->mc_conns[candidate].msc_active--;
+		ldap_pvt_thread_mutex_unlock( &mc->mc_om_mutex);
+		goto finish;
+	}
+
+retry:
+	if (bc->timeout && bc->stoptime < slap_get_time()) {
+		int		timeout_err;
+		timeout_err = op->o_protocol >= LDAP_VERSION3 ?
+			LDAP_ADMINLIMIT_EXCEEDED : LDAP_OTHER;
+		rs->sr_err = timeout_err;
+		rs->sr_text = "Operation timed out before it was sent to target";
+		asyncmeta_error_cleanup(op, rs, bc, mc, candidate);
+		goto finish;
+	}
+
+	rc = asyncmeta_dobind_init_with_retry(op, rs, bc, mc, candidate);
+	switch (rc)
+	{
+	case META_SEARCH_CANDIDATE:
+		/* target is already bound, just send the request */
+		Debug( LDAP_DEBUG_TRACE, "%s asyncmeta_back_compare:  "
+		       "cnd=\"%d\"\n", op->o_log_prefix, candidate );
+
+		rc = asyncmeta_back_compare_start( op, rs, mc, bc, candidate, 1);
+		if (rc == META_SEARCH_ERR) {
+			asyncmeta_error_cleanup(op, rs, bc, mc, candidate);
+			goto finish;
+
+		} else if (rc == META_SEARCH_NEED_BIND) {
+			goto retry;
+		}
+		break;
+	case META_SEARCH_NOT_CANDIDATE:
+		Debug( LDAP_DEBUG_TRACE, "%s asyncmeta_back_compare: NOT_CANDIDATE "
+		       "cnd=\"%d\"\n", op->o_log_prefix, candidate );
+		asyncmeta_error_cleanup(op, rs, bc, mc, candidate);
+		goto finish;
+
+	case META_SEARCH_NEED_BIND:
+	case META_SEARCH_BINDING:
+			Debug( LDAP_DEBUG_TRACE, "%s asyncmeta_back_compare: BINDING "
+			       "cnd=\"%d\" %p\n", op->o_log_prefix, candidate , &mc->mc_conns[candidate]);
+			/* Todo add the context to the message queue but do not send the request
+			   the receiver must send this when we are done binding */
+			/* question - how would do receiver know to which targets??? */
+			break;
+
+	case META_SEARCH_ERR:
+			Debug( LDAP_DEBUG_TRACE, "%s asyncmeta_back_compare: ERR "
+			       "cnd=\"%d\"\n", op->o_log_prefix, candidate );
+			asyncmeta_error_cleanup(op, rs, bc, mc, candidate);
+			goto finish;
+		default:
+			assert( 0 );
+			break;
+		}
+
+	ldap_pvt_thread_mutex_lock( &mc->mc_om_mutex);
+	mc->mc_conns[candidate].msc_active--;
+	asyncmeta_start_one_listener(mc, candidates, bc, candidate);
+	bc->bc_active--;
+	ldap_pvt_thread_mutex_unlock( &mc->mc_om_mutex);
+	rs->sr_err = SLAPD_ASYNCOP;
+finish:
+	return rs->sr_err;
+}