Issue #1258 - Part 2: Use binoc-central version of ldap

1 files changed, 1659 insertions, 0 deletions

diff --git a/ldap/c-sdk/libldap/request.c b/ldap/c-sdk/libldap/request.c
new file mode 100644
index 000000000..d379917b2
--- /dev/null
+++ b/ldap/c-sdk/libldap/request.c
@@ -0,0 +1,1659 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ * 
+ * The contents of this file are subject to the Mozilla Public License Version 
+ * 1.1 (the "License"); you may not use this file except in compliance with 
+ * the License. You may obtain a copy of the License at 
+ * http://www.mozilla.org/MPL/
+ * 
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ * 
+ * The Original Code is Mozilla Communicator client code, released
+ * March 31, 1998.
+ * 
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1998-1999
+ * the Initial Developer. All Rights Reserved.
+ * 
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ * 
+ * ***** END LICENSE BLOCK ***** */
+/*
+ *  Copyright (c) 1995 Regents of the University of Michigan.
+ *  All rights reserved.
+ */
+/*
+ *  request.c - sending of ldap requests; handling of referrals
+ */
+
+#if 0
+#ifndef lint 
+static char copyright[] = "@(#) Copyright (c) 1995 Regents of the University of Michigan.\nAll rights reserved.\n";
+#endif
+#endif
+
+#include "ldap-int.h"
+
+static LDAPConn *find_connection( LDAP *ld, LDAPServer *srv, int any );
+static void free_servers( LDAPServer *srvlist );
+static int chase_one_referral( LDAP *ld, LDAPRequest *lr, LDAPRequest *origreq,
+    char *refurl, char *desc, int *unknownp, int is_reference );
+static int re_encode_request( LDAP *ld, BerElement *origber,
+    int msgid, LDAPURLDesc *ludp, BerElement **berp, int is_reference );
+
+#ifdef LDAP_DNS
+static LDAPServer *dn2servers( LDAP *ld, char *dn );
+#endif /* LDAP_DNS */
+
+
+/* returns an LDAP error code and also sets error inside LDAP * */
+int
+nsldapi_alloc_ber_with_options( LDAP *ld, BerElement **berp )
+{
+	int	err;
+
+	LDAP_MUTEX_LOCK( ld, LDAP_OPTION_LOCK );
+    	if (( *berp = ber_alloc_t( ld->ld_lberoptions )) == NULLBER ) {
+		err = LDAP_NO_MEMORY;
+		LDAP_SET_LDERRNO( ld, err, NULL, NULL );
+	} else {
+		err = LDAP_SUCCESS;
+#ifdef STR_TRANSLATION
+		nsldapi_set_ber_options( ld, *berp );
+#endif /* STR_TRANSLATION */
+	}
+	LDAP_MUTEX_UNLOCK( ld, LDAP_OPTION_LOCK );
+
+	return( err );
+}
+
+
+void
+nsldapi_set_ber_options( LDAP *ld, BerElement *ber )
+{
+	ber->ber_options = ld->ld_lberoptions;
+#ifdef STR_TRANSLATION
+	if (( ld->ld_lberoptions & LBER_OPT_TRANSLATE_STRINGS ) != 0 ) {
+		ber_set_string_translators( ber,
+		    ld->ld_lber_encode_translate_proc,
+		    ld->ld_lber_decode_translate_proc );
+	}
+#endif /* STR_TRANSLATION */
+}
+
+
+/* returns the message id of the request or -1 if an error occurs */
+int
+nsldapi_send_initial_request( LDAP *ld, int msgid, unsigned long msgtype,
+	char *dn, BerElement *ber )
+{
+	LDAPServer	*servers;
+	
+	LDAPDebug( LDAP_DEBUG_TRACE, "nsldapi_send_initial_request\n", 0,0,0 );
+
+#ifdef LDAP_DNS
+	LDAP_MUTEX_LOCK( ld, LDAP_OPTION_LOCK );
+	if (( ld->ld_options & LDAP_BITOPT_DNS ) != 0 && ldap_is_dns_dn( dn )) {
+		if (( servers = dn2servers( ld, dn )) == NULL ) {
+			ber_free( ber, 1 );
+			LDAP_MUTEX_UNLOCK( ld, LDAP_OPTION_LOCK );
+			return( -1 );
+		}
+
+#ifdef LDAP_DEBUG
+		if ( ldap_debug & LDAP_DEBUG_TRACE ) {
+			LDAPServer	*srv;
+			char    msg[256];
+
+			for ( srv = servers; srv != NULL;
+			    srv = srv->lsrv_next ) {
+				sprintf( msg,
+				    "LDAP server %s:  dn %s, port %d\n",
+				    srv->lsrv_host, ( srv->lsrv_dn == NULL ) ?
+				    "(default)" : srv->lsrv_dn,
+				    srv->lsrv_port );
+				ber_err_print( msg );
+			}
+		}
+#endif /* LDAP_DEBUG */
+	} else {
+#endif /* LDAP_DNS */
+		/*
+		 * use of DNS is turned off or this is an LDAP DN...
+		 * use our default connection
+		 */
+		servers = NULL;
+#ifdef LDAP_DNS
+	}	
+	LDAP_MUTEX_UNLOCK( ld, LDAP_OPTION_LOCK );
+#endif /* LDAP_DNS */
+
+	return( nsldapi_send_server_request( ld, ber, msgid, NULL,
+	    servers, NULL, ( msgtype == LDAP_REQ_BIND ) ? dn : NULL, 0 ));
+}
+
+
+/* returns the message id of the request or -1 if an error occurs */
+int
+nsldapi_send_server_request(
+    LDAP *ld,			/* session handle */
+    BerElement *ber,		/* message to send */
+    int msgid,			/* ID of message to send */
+    LDAPRequest *parentreq,	/* non-NULL for referred requests */
+    LDAPServer *srvlist,	/* servers to connect to (NULL for default) */
+    LDAPConn *lc,		/* connection to use (NULL for default) */
+    char *bindreqdn,		/* non-NULL for bind requests */
+    int bind			/* perform a bind after opening new conn.? */
+)
+{
+	LDAPRequest	*lr;
+	int		err;
+	int		incparent; /* did we bump parent's ref count? */
+	/* EPIPE and Unsolicited Response handling variables */
+	int				res_rc     = 0;
+	int				epipe_err  = 0;
+	int				ext_res_rc = 0;
+	char			*ext_oid   = NULL;
+	struct berval	*ext_data  = NULL;
+	LDAPMessage		*ext_res   = NULL;
+
+	LDAPDebug( LDAP_DEBUG_TRACE, "nsldapi_send_server_request\n", 0, 0, 0 );
+
+	incparent = 0;
+	LDAP_MUTEX_LOCK( ld, LDAP_CONN_LOCK );
+	if ( lc == NULL ) {
+		if ( srvlist == NULL ) {
+			if ( ld->ld_defconn == NULL ) {
+				LDAP_MUTEX_LOCK( ld, LDAP_OPTION_LOCK );
+				if ( bindreqdn == NULL && ( ld->ld_options
+				    & LDAP_BITOPT_RECONNECT ) != 0 ) {
+					LDAP_SET_LDERRNO( ld, LDAP_SERVER_DOWN,
+					    NULL, NULL );
+					ber_free( ber, 1 );
+					LDAP_MUTEX_UNLOCK( ld, LDAP_OPTION_LOCK );
+					LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+					return( -1 );
+				}
+				LDAP_MUTEX_UNLOCK( ld, LDAP_OPTION_LOCK );
+
+				if ( nsldapi_open_ldap_defconn( ld ) < 0 ) {
+					ber_free( ber, 1 );
+					LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+					return( -1 );
+				}
+			}
+			lc = ld->ld_defconn;
+		} else {
+			if (( lc = find_connection( ld, srvlist, 1 )) ==
+			    NULL ) {
+				if ( bind && (parentreq != NULL) ) {
+					/* Remember the bind in the parent */
+					incparent = 1;
+					++parentreq->lr_outrefcnt;
+				}
+
+				lc = nsldapi_new_connection( ld, &srvlist, 0,
+					1, bind );
+			}
+			free_servers( srvlist );
+		}
+	}
+
+
+	/*
+     * return a fatal error if:
+     * 1. no connections exists
+	 * or 
+     * 2. the connection is dead
+	 * or 
+     * 3. it is not in the connected state with normal (non async) I/O
+	 */
+	if (   lc == NULL
+                    || ( lc->lconn_status == LDAP_CONNST_DEAD )
+                    || ( 0 == (ld->ld_options & LDAP_BITOPT_ASYNC) &&
+                        lc->lconn_status != LDAP_CONNST_CONNECTED) ) {
+
+		ber_free( ber, 1 );
+		if ( lc != NULL ) {
+			LDAP_SET_LDERRNO( ld, LDAP_SERVER_DOWN, NULL, NULL );
+		}
+		if ( incparent ) {
+			/* Forget about the bind */
+			--parentreq->lr_outrefcnt; 
+		}
+		LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+		return( -1 );
+	}
+
+	if (( lr = nsldapi_new_request( lc, ber, msgid,
+	    1 /* expect a response */)) == NULL
+	    || ( bindreqdn != NULL && ( bindreqdn =
+	    nsldapi_strdup( bindreqdn )) == NULL )) {
+		if ( lr != NULL ) {
+			NSLDAPI_FREE( lr );
+		}
+		LDAP_SET_LDERRNO( ld, LDAP_NO_MEMORY, NULL, NULL );
+		nsldapi_free_connection( ld, lc, NULL, NULL, 0, 0 );
+		ber_free( ber, 1 );
+		if ( incparent ) {
+			/* Forget about the bind */
+			--parentreq->lr_outrefcnt; 
+		}
+		LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+		return( -1 );
+	} 
+	lr->lr_binddn = bindreqdn;
+
+	if ( parentreq != NULL ) {	/* sub-request */
+		if ( !incparent ) { 
+			/* Increment if we didn't do it before the bind */
+			++parentreq->lr_outrefcnt;
+		}
+		lr->lr_origid = parentreq->lr_origid;
+		lr->lr_parentcnt = parentreq->lr_parentcnt + 1;
+		lr->lr_parent = parentreq;
+		if ( parentreq->lr_child != NULL ) {
+			lr->lr_sibling = parentreq->lr_child;
+		}
+		parentreq->lr_child = lr;
+	} else {			/* original request */
+		lr->lr_origid = lr->lr_msgid;
+	}
+
+	LDAP_MUTEX_LOCK( ld, LDAP_REQ_LOCK );
+        /* add new request to the end of the list of outstanding requests */
+	nsldapi_queue_request_nolock( ld, lr );
+
+	/*
+	 * Issue a non-blocking poll() if we need to check this
+	 * connection's status.
+	 */
+	if ( lc->lconn_status == LDAP_CONNST_CONNECTING ||
+	    lc->lconn_pending_requests > 0 ) {
+		struct timeval	tv;
+
+		tv.tv_sec = tv.tv_usec = 0;
+		(void)nsldapi_iostatus_poll( ld, &tv );
+	}
+
+	/*
+	 * If the connect is pending, check to see if it has now completed.
+	 */
+	if ( lc->lconn_status == LDAP_CONNST_CONNECTING &&
+	    nsldapi_iostatus_is_write_ready( ld, lc->lconn_sb )) {
+		lc->lconn_status = LDAP_CONNST_CONNECTED;
+
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "nsldapi_send_server_request: connection 0x%p -"
+		    " LDAP_CONNST_CONNECTING -> LDAP_CONNST_CONNECTED\n",
+		    lc, 0, 0 );
+	}
+
+    if ( lc->lconn_status == LDAP_CONNST_CONNECTING ||
+                        lc->lconn_pending_requests > 0 ) {
+       /*
+        * The connect is not yet complete, or there are existing
+        * requests that have not yet been sent to the server.
+        * Delay sending this request.
+        */
+		lr->lr_status = LDAP_REQST_WRITING;
+                ++lc->lconn_pending_requests;
+		nsldapi_iostatus_interest_write( ld, lc->lconn_sb );
+
+		/*
+		 * If the connection is now connected, and it is ready
+		 * to accept some more outbound data, send as many
+		 * pending requests as possible.
+		 */
+		if ( lc->lconn_status != LDAP_CONNST_CONNECTING
+		    && nsldapi_iostatus_is_write_ready( ld, lc->lconn_sb )) {
+			if ( nsldapi_send_pending_requests_nolock( ld, lc )
+			    == -1 ) {	/* error */
+				/*
+				 * Since nsldapi_send_pending_requests_nolock()
+				 * sets LDAP errno, there is no need to do so
+				 * here.
+				 */
+				LDAP_MUTEX_UNLOCK( ld, LDAP_REQ_LOCK );
+				LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+				return( -1 );
+			}
+		}
+
+	    } else {
+		    if (( err = nsldapi_send_ber_message( ld, lc->lconn_sb,
+				    ber, 0 /* do not free ber */, 
+				    1 /* will handle EPIPE */ )) != 0 ) {
+				    
+				epipe_err = LDAP_GET_ERRNO( ld );
+				if ( epipe_err == EPIPE ) {
+					res_rc = nsldapi_result_nolock(ld, LDAP_RES_UNSOLICITED, 1, 
+									1, (struct timeval *) NULL, &ext_res);
+					if ( ( res_rc == LDAP_RES_EXTENDED ) && ext_res ) {
+						ext_res_rc = ldap_parse_extended_result( ld, ext_res, 
+										&ext_oid, &ext_data, 0 );
+						if ( ext_res_rc != LDAP_SUCCESS ) {
+							if ( ext_res ) {
+								ldap_msgfree( ext_res );
+							}					
+							nsldapi_connection_lost_nolock( ld, lc->lconn_sb );
+						} else {
+#ifdef LDAP_DEBUG
+	LDAPDebug( LDAP_DEBUG_TRACE, 
+			   "nsldapi_send_server_request: Unsolicited response\n", 0, 0, 0 );
+	if ( ext_oid ) {
+		LDAPDebug( LDAP_DEBUG_TRACE, 
+				"nsldapi_send_server_request: Unsolicited response oid: %s\n", 
+				   ext_oid, 0, 0 );
+	}
+	if ( ext_data && ext_data->bv_len && ext_data->bv_val ) {
+		LDAPDebug( LDAP_DEBUG_TRACE, 
+				"nsldapi_send_server_request: Unsolicited response len: %d\n", 
+				   ext_data->bv_len, 0, 0 );
+		LDAPDebug( LDAP_DEBUG_TRACE, 
+				"nsldapi_send_server_request: Unsolicited response val: %s\n", 
+				   ext_data->bv_val, 0, 0 );
+	}
+	if ( !ext_oid && !ext_data ) { 					
+		LDAPDebug( LDAP_DEBUG_TRACE, 
+				"nsldapi_send_server_request: Unsolicited response is empty\n", 
+				   0, 0, 0 );
+	}
+#endif /* LDAP_DEBUG */
+							if ( ext_oid ) {
+								if ( strcmp ( ext_oid, 
+										LDAP_NOTICE_OF_DISCONNECTION ) == 0 ) {
+									if ( ext_data ) {
+										ber_bvfree( ext_data );
+									}
+									if ( ext_oid ) {
+										ldap_memfree( ext_oid );
+									}
+									if ( ext_res ) {
+										ldap_msgfree( ext_res );
+									}
+									nsldapi_connection_lost_nolock( ld, 
+														lc->lconn_sb );
+									nsldapi_free_request( ld, lr, 0 );
+									nsldapi_free_connection( ld, lc, 
+													NULL, NULL, 0, 0 );
+									LDAP_MUTEX_UNLOCK( ld, LDAP_REQ_LOCK );
+									LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+									return( -1 );					
+								}
+							}
+						}
+					} else {
+						if ( ext_res ) {
+							ldap_msgfree( ext_res );
+						}				
+						nsldapi_connection_lost_nolock( ld, lc->lconn_sb );
+					}
+				}
+
+                /* need to continue write later */
+                if (err == -2 ) {       
+                   	lr->lr_status = LDAP_REQST_WRITING;
+                   	++lc->lconn_pending_requests;
+                   	nsldapi_iostatus_interest_write( ld, lc->lconn_sb );
+                } else {
+					LDAP_SET_LDERRNO( ld, LDAP_SERVER_DOWN, NULL, NULL );
+					nsldapi_free_request( ld, lr, 0 );
+                    nsldapi_free_connection( ld, lc, NULL, NULL, 0, 0 );
+					LDAP_MUTEX_UNLOCK( ld, LDAP_REQ_LOCK );
+					LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+					return( -1 );
+				}
+
+			} else {
+				if ( parentreq == NULL ) {
+					ber->ber_end = ber->ber_ptr;
+					ber->ber_ptr = ber->ber_buf;
+				}
+
+				/* sent -- waiting for a response */
+				if (ld->ld_options & LDAP_BITOPT_ASYNC) {
+					lc->lconn_status = LDAP_CONNST_CONNECTED;
+				}
+
+				nsldapi_iostatus_interest_read( ld, lc->lconn_sb );
+			}
+	}
+	LDAP_MUTEX_UNLOCK( ld, LDAP_REQ_LOCK );
+	LDAP_MUTEX_UNLOCK( ld, LDAP_CONN_LOCK );
+
+	LDAP_SET_LDERRNO( ld, LDAP_SUCCESS, NULL, NULL );
+	return( msgid );
+}
+
+
+/*
+ * nsldapi_send_ber_message(): Attempt to send a BER-encoded message.
+ * If freeit is non-zero, ber is freed when the send succeeds.
+ * If errno is EPIPE and epipe_handler is set we let the caller
+ * deal with EPIPE and dont call lost_nolock here but the caller 
+ * should call lost_nolock itself when done with handling EPIPE.
+ *
+ * Return values:
+ *    0: message sent successfully.
+ *   -1: a fatal error occurred while trying to send.
+ *   -2: async. I/O is enabled and the send would block.
+ */
+int
+nsldapi_send_ber_message( LDAP *ld, Sockbuf *sb, BerElement *ber, int freeit,
+		int epipe_handler )
+{
+	int	rc = 0;	/* optimistic */
+	int	async = ( 0 != (ld->ld_options & LDAP_BITOPT_ASYNC));
+	int	more_to_send = 1;
+
+	while ( more_to_send) {
+		 /*
+		  * ber_flush() doesn't set errno on EOF, so we pre-set it to
+		  * zero to avoid getting tricked by leftover "EAGAIN" errors
+		  */
+		LDAP_SET_ERRNO( ld, 0 );
+
+		if ( ber_flush( sb, ber, freeit ) == 0 ) {
+			more_to_send = 0;	/* success */
+		} else {
+			int terrno = LDAP_GET_ERRNO( ld );
+			if ( NSLDAPI_ERRNO_IO_INPROGRESS( terrno )) {
+				if ( async ) {
+					rc = -2;
+					break;
+				}
+			} else {
+				if ( !(epipe_handler && ( terrno == EPIPE )) ) {
+					nsldapi_connection_lost_nolock( ld, sb );
+				}
+				rc = -1;	/* fatal error */
+				break;
+			}
+		}
+    }
+
+	return( rc );
+}
+
+
+/*
+ * nsldapi_send_pending_requests_nolock(): Send one or more pending requests
+ * that are associated with connection 'lc'.
+ *
+ * Return values:  0 -- success.
+ *		  -1 -- fatal error; connection closed.
+ *
+ * Must be called with these two mutexes locked, in this order:
+ *	LDAP_CONN_LOCK
+ *	LDAP_REQ_LOCK
+ */
+int
+nsldapi_send_pending_requests_nolock( LDAP *ld, LDAPConn *lc )
+{
+	int		err;
+	int		waiting_for_a_response = 0;
+	int		rc = 0;
+	LDAPRequest	*lr;
+	char		*logname = "nsldapi_send_pending_requests_nolock";
+
+	LDAPDebug( LDAP_DEBUG_TRACE, "%s\n", logname, 0, 0 );
+
+	for ( lr = ld->ld_requests; lr != NULL; lr = lr->lr_next ) {
+		/*
+		 * This code relies on the fact that the ld_requests list
+		 * is in order from oldest to newest request (the oldest
+		 * requests that have not yet been sent to the server are
+		 * sent first).
+		 */
+		if ( lr->lr_status == LDAP_REQST_WRITING
+		    && lr->lr_conn == lc ) {
+			err = nsldapi_send_ber_message( ld, lc->lconn_sb,
+			    lr->lr_ber, 0 /* do not free ber */, 
+			    0 /* will not handle EPIPE */ );
+			if ( err == 0 ) {		/* send succeeded */
+				LDAPDebug( LDAP_DEBUG_TRACE,
+				    "%s: 0x%p SENT\n", logname, lr, 0 );
+				lr->lr_ber->ber_end = lr->lr_ber->ber_ptr;
+				lr->lr_ber->ber_ptr = lr->lr_ber->ber_buf;
+				lr->lr_status = LDAP_REQST_INPROGRESS;
+				--lc->lconn_pending_requests;
+			} else if ( err == -2 ) {	/* would block */
+				rc = 0; /* not an error */
+				LDAPDebug( LDAP_DEBUG_TRACE,
+				    "%s: 0x%p WOULD BLOCK\n", logname, lr, 0 );
+				break;
+			} else {			/* fatal error */
+				LDAPDebug( LDAP_DEBUG_TRACE,
+				    "%s: 0x%p FATAL ERROR\n", logname, lr, 0 );
+				LDAP_SET_LDERRNO( ld, LDAP_SERVER_DOWN,
+				    NULL, NULL );
+				nsldapi_free_request( ld, lr, 0 );
+				lr = NULL;
+				nsldapi_free_connection( ld, lc, NULL, NULL,
+				    0, 0 );
+				lc = NULL;
+				rc = -1;
+				break;
+			}
+		}
+
+		if (lr->lr_status == LDAP_REQST_INPROGRESS ) {
+			if (lr->lr_expect_resp) {
+				++waiting_for_a_response;
+			} else {
+				LDAPDebug( LDAP_DEBUG_TRACE,
+				    "%s: 0x%p NO RESPONSE EXPECTED;"
+				    " freeing request \n", logname, lr, 0 );
+				nsldapi_free_request( ld, lr, 0 );
+				lr = NULL;
+			}
+		}
+	}
+
+	if ( lc != NULL ) {
+		if ( lc->lconn_pending_requests < 1 ) {
+			/* no need to poll for "write ready" any longer */
+			nsldapi_iostatus_interest_clear( ld, lc->lconn_sb );
+		}
+
+		if ( waiting_for_a_response ) {
+			/* need to poll for "read ready" */
+			nsldapi_iostatus_interest_read( ld, lc->lconn_sb );
+		}
+	}
+
+	LDAPDebug( LDAP_DEBUG_TRACE, "%s <- %d\n", logname, rc, 0 );
+	return( rc );
+}
+
+
+LDAPConn *
+nsldapi_new_connection( LDAP *ld, LDAPServer **srvlistp, int use_ldsb,
+	int connect, int bind )
+{
+	int		rc = -1;
+	LDAPConn	*lc;
+	LDAPServer	*prevsrv, *srv;
+	Sockbuf		*sb = NULL;
+
+	/*
+	 * make a new LDAP server connection
+	 */
+	if (( lc = (LDAPConn *)NSLDAPI_CALLOC( 1, sizeof( LDAPConn ))) == NULL
+	    || ( !use_ldsb && ( sb = ber_sockbuf_alloc()) == NULL )) {
+		if ( lc != NULL ) {
+			NSLDAPI_FREE( (char *)lc );
+		}
+		LDAP_SET_LDERRNO( ld, LDAP_NO_MEMORY, NULL, NULL );
+		return( NULL );
+	}
+
+	LDAP_MUTEX_LOCK( ld, LDAP_OPTION_LOCK );
+	if ( !use_ldsb ) {
+		/*
+		 * we have allocated a new sockbuf
+		 * set I/O routines to match those in default LDAP sockbuf
+		 */
+		IFP				sb_fn;
+		struct lber_x_ext_io_fns	extiofns;
+		
+		extiofns.lbextiofn_size = LBER_X_EXTIO_FNS_SIZE;
+
+		if ( ber_sockbuf_get_option( ld->ld_sbp,
+		    LBER_SOCKBUF_OPT_EXT_IO_FNS, &extiofns ) == 0 ) {
+			ber_sockbuf_set_option( sb,
+			    LBER_SOCKBUF_OPT_EXT_IO_FNS, &extiofns );
+		}
+		if ( ber_sockbuf_get_option( ld->ld_sbp,
+		    LBER_SOCKBUF_OPT_READ_FN, (void *)&sb_fn ) == 0
+		    && sb_fn != NULL ) {
+			ber_sockbuf_set_option( sb, LBER_SOCKBUF_OPT_READ_FN,
+			    (void *)sb_fn );
+		}
+		if ( ber_sockbuf_get_option( ld->ld_sbp,
+		    LBER_SOCKBUF_OPT_WRITE_FN, (void *)&sb_fn ) == 0
+		    && sb_fn != NULL ) {
+			ber_sockbuf_set_option( sb, LBER_SOCKBUF_OPT_WRITE_FN,
+			    (void *)sb_fn );
+		}
+	}
+
+	lc->lconn_sb = ( use_ldsb ) ? ld->ld_sbp : sb;
+	lc->lconn_version = ld->ld_version;	/* inherited */
+	LDAP_MUTEX_UNLOCK( ld, LDAP_OPTION_LOCK );
+
+	if ( connect ) {
+		prevsrv = NULL;
+        /* 
+         * save the return code for later
+         */ 
+		for ( srv = *srvlistp; srv != NULL; srv = srv->lsrv_next ) {
+			rc = nsldapi_connect_to_host( ld, lc->lconn_sb,
+				   srv->lsrv_host, srv->lsrv_port,
+			       (  srv->lsrv_options & LDAP_SRV_OPT_SECURE ) != 0,
+					&lc->lconn_krbinstance );
+			if (rc != -1) {
+				break;
+			}
+			prevsrv = srv;
+		}
+
+		if ( srv == NULL ) {
+		    if ( !use_ldsb ) {
+			NSLDAPI_FREE( (char *)lc->lconn_sb );
+		    }
+		    NSLDAPI_FREE( (char *)lc );
+		    /* nsldapi_open_ldap_connection has already set ld_errno */
+		    return( NULL );
+		}
+
+		if ( prevsrv == NULL ) {
+		    *srvlistp = srv->lsrv_next;
+		} else {
+		    prevsrv->lsrv_next = srv->lsrv_next;
+		}
+		lc->lconn_server = srv;
+	}
+
+        if ( 0 != (ld->ld_options & LDAP_BITOPT_ASYNC)) {
+                /*
+                 * Technically, the socket may already be connected but we are
+                 * not sure. By setting the state to LDAP_CONNST_CONNECTING, we
+                 * ensure that we will check the socket status to make sure it
+                 * is connected before we try to send any LDAP messages.
+                 */
+        lc->lconn_status = LDAP_CONNST_CONNECTING;
+    } else {
+        lc->lconn_status = LDAP_CONNST_CONNECTED;
+    }
+    
+	lc->lconn_next = ld->ld_conns;
+	ld->ld_conns = lc;
+
+	/*
+	 * XXX for now, we always do a synchronous bind.  This will have
+	 * to change in the long run...
+	 */
+	if ( bind ) {
+		int		err, lderr, freepasswd, authmethod;
+		char		*binddn, *passwd;
+		LDAPConn	*savedefconn;
+
+		freepasswd = err = 0;
+
+		if ( ld->ld_rebind_fn == NULL ) {
+			binddn = passwd = "";
+			authmethod = LDAP_AUTH_SIMPLE;
+		} else {
+			if (( lderr = (*ld->ld_rebind_fn)( ld, &binddn, &passwd,
+			    &authmethod, 0, ld->ld_rebind_arg ))
+			    == LDAP_SUCCESS ) {
+				freepasswd = 1;
+			} else {
+				LDAP_SET_LDERRNO( ld, lderr, NULL, NULL );
+				err = -1;
+			}
+		}
+
+
+		if ( err == 0 ) {
+			savedefconn = ld->ld_defconn;
+			ld->ld_defconn = lc;
+			++lc->lconn_refcnt;	/* avoid premature free */
+
+			/*
+			 * when binding, we will back down as low as LDAPv2
+			 * if we get back "protocol error" from bind attempts
+			 */
+			for ( ;; ) {
+				/* LDAP_MUTEX_UNLOCK(ld, LDAP_CONN_LOCK); */
+				if (( lderr = ldap_bind_s( ld, binddn, passwd,
+				    authmethod )) == LDAP_SUCCESS ) {
+					/* LDAP_MUTEX_LOCK(ld, LDAP_CONN_LOCK); */
+					break;
+				}
+				/* LDAP_MUTEX_LOCK(ld, LDAP_CONN_LOCK); */
+				if ( lc->lconn_version <= LDAP_VERSION2
+				    || lderr != LDAP_PROTOCOL_ERROR ) {
+					err = -1;
+					break;
+				}
+				--lc->lconn_version;	/* try lower version */
+			}
+			--lc->lconn_refcnt;
+			ld->ld_defconn = savedefconn;
+		}
+
+		if ( freepasswd ) {
+			(*ld->ld_rebind_fn)( ld, &binddn, &passwd,
+				&authmethod, 1, ld->ld_rebind_arg );
+		}
+
+		if ( err != 0 ) {
+			nsldapi_free_connection( ld, lc, NULL, NULL, 1, 0 );
+			lc = NULL;
+		}
+	}
+
+	return( lc );
+}
+
+
+#define LDAP_CONN_SAMEHOST( h1, h2 ) \
+	(( (h1) == NULL && (h2) == NULL ) || \
+	( (h1) != NULL && (h2) != NULL && strcasecmp( (h1), (h2) ) == 0 ))
+
+static LDAPConn *
+find_connection( LDAP *ld, LDAPServer *srv, int any )
+/*
+ * return an existing connection (if any) to the server srv
+ * if "any" is non-zero, check for any server in the "srv" chain
+ */
+{
+	LDAPConn	*lc;
+	LDAPServer	*ls;
+
+	for ( lc = ld->ld_conns; lc != NULL; lc = lc->lconn_next ) {
+		for ( ls = srv; ls != NULL; ls = ls->lsrv_next ) {
+			if ( LDAP_CONN_SAMEHOST( ls->lsrv_host,
+			    lc->lconn_server->lsrv_host )
+			    && ls->lsrv_port == lc->lconn_server->lsrv_port
+			    && ls->lsrv_options ==
+			    lc->lconn_server->lsrv_options ) {
+				return( lc );
+			}
+			if ( !any ) {
+				break;
+			}
+		}
+	}
+
+	return( NULL );
+}
+
+
+void
+nsldapi_free_connection( LDAP *ld, LDAPConn *lc, LDAPControl **serverctrls,
+    LDAPControl **clientctrls, int force, int unbind )
+{
+	LDAPConn	*tmplc, *prevlc;
+
+	LDAPDebug( LDAP_DEBUG_TRACE, "nsldapi_free_connection\n", 0, 0, 0 );
+
+	if ( force || --lc->lconn_refcnt <= 0 ) {
+		nsldapi_iostatus_interest_clear( ld, lc->lconn_sb );
+		if ( lc->lconn_status == LDAP_CONNST_CONNECTED ) {
+			if ( unbind ) {
+				nsldapi_send_unbind( ld, lc->lconn_sb,
+				    serverctrls, clientctrls );
+			}
+		}
+		nsldapi_close_connection( ld, lc->lconn_sb );
+		prevlc = NULL;
+		for ( tmplc = ld->ld_conns; tmplc != NULL;
+		    tmplc = tmplc->lconn_next ) {
+			if ( tmplc == lc ) {
+				if ( prevlc == NULL ) {
+				    ld->ld_conns = tmplc->lconn_next;
+				} else {
+				    prevlc->lconn_next = tmplc->lconn_next;
+				}
+				break;
+			}
+			prevlc = tmplc;
+		}
+		free_servers( lc->lconn_server );
+		if ( lc->lconn_krbinstance != NULL ) {
+			NSLDAPI_FREE( lc->lconn_krbinstance );
+		}
+		/*
+		 * if this is the default connection (lc->lconn_sb==ld->ld_sbp)
+		 * we do not free the Sockbuf here since it will be freed
+		 * later inside ldap_unbind().
+		 */
+		if ( lc->lconn_sb != ld->ld_sbp ) {
+			ber_sockbuf_free( lc->lconn_sb );
+			lc->lconn_sb = NULL;
+		}
+		if ( lc->lconn_ber != NULLBER ) {
+			ber_free( lc->lconn_ber, 1 );
+		}
+		if ( lc->lconn_binddn != NULL ) {
+			NSLDAPI_FREE( lc->lconn_binddn );
+		}
+#ifdef LDAP_SASLIO_HOOKS
+		if ( lc->lconn_sasl_ctx ) { /* the sasl connection context */
+			sasl_dispose(&lc->lconn_sasl_ctx);
+			lc->lconn_sasl_ctx = NULL;
+		}
+#endif /* LDAP_SASLIO_HOOKS */
+		NSLDAPI_FREE( lc );
+		LDAPDebug( LDAP_DEBUG_TRACE, "nsldapi_free_connection: actually freed\n",
+		    0, 0, 0 );
+	} else {
+		lc->lconn_lastused = time( 0 );
+		LDAPDebug( LDAP_DEBUG_TRACE, "nsldapi_free_connection: refcnt %d\n",
+		    lc->lconn_refcnt, 0, 0 );
+	}
+}
+
+
+#ifdef LDAP_DEBUG
+void
+nsldapi_dump_connection( LDAP *ld, LDAPConn *lconns, int all )
+{
+	LDAPConn	*lc;
+	char        msg[256];
+/* CTIME for this platform doesn't use this. */
+#if !defined(SUNOS4) && !defined(_WIN32) && !defined(LINUX) && !defined(macintosh)
+	char		buf[26];
+#endif
+
+	sprintf( msg, "** Connection%s:\n", all ? "s" : "" );
+	ber_err_print( msg );
+	for ( lc = lconns; lc != NULL; lc = lc->lconn_next ) {
+		if ( lc->lconn_server != NULL ) {
+                        sprintf( msg, "* 0x%p - host: %s  port: %d  secure: %s%s\n",
+                                lc, ( lc->lconn_server->lsrv_host == NULL ) ? "(null)"
+			    : lc->lconn_server->lsrv_host,
+			    lc->lconn_server->lsrv_port,
+			    ( lc->lconn_server->lsrv_options &
+			    LDAP_SRV_OPT_SECURE ) ? "Yes" :
+			    "No", ( lc->lconn_sb == ld->ld_sbp ) ?
+			    "  (default)" : "" );
+			ber_err_print( msg );
+		}
+                sprintf( msg, "  refcnt: %d  pending: %d  status: %s\n",
+                    lc->lconn_refcnt, lc->lconn_pending_requests,
+                    ( lc->lconn_status == LDAP_CONNST_CONNECTING )
+                    ? "Connecting" :
+		    ( lc->lconn_status == LDAP_CONNST_DEAD ) ? "Dead" :
+		    "Connected" );
+		ber_err_print( msg );
+		sprintf( msg, "  last used: %s",
+		    NSLDAPI_CTIME( (time_t *) &lc->lconn_lastused, buf,
+				sizeof(buf) ));
+		ber_err_print( msg );
+		if ( lc->lconn_ber != NULLBER ) {
+			ber_err_print( "  partial response has been received:\n" );
+			ber_dump( lc->lconn_ber, 1 );
+		}
+		ber_err_print( "\n" );
+
+		if ( !all ) {
+			break;
+		}
+	}
+}
+
+
+void
+nsldapi_dump_requests_and_responses( LDAP *ld )
+{
+	LDAPRequest	*lr;
+	LDAPMessage	*lm, *l;
+	char        msg[256];
+
+	ber_err_print( "** Outstanding Requests:\n" );
+	LDAP_MUTEX_LOCK( ld, LDAP_REQ_LOCK );
+	if (( lr = ld->ld_requests ) == NULL ) {
+		ber_err_print( "   Empty\n" );
+	}
+	for ( ; lr != NULL; lr = lr->lr_next ) {
+            sprintf( msg, " * 0x%p - msgid %d,  origid %d, status %s\n",
+                lr, lr->lr_msgid, lr->lr_origid, ( lr->lr_status ==
+		LDAP_REQST_INPROGRESS ) ? "InProgress" :
+		( lr->lr_status == LDAP_REQST_CHASINGREFS ) ? "ChasingRefs" :
+		( lr->lr_status == LDAP_REQST_CONNDEAD ) ? "Dead" :
+		"Writing" );
+	    ber_err_print( msg );
+	    sprintf( msg, "   outstanding referrals %d, parent count %d\n",
+		    lr->lr_outrefcnt, lr->lr_parentcnt );
+	    ber_err_print( msg );
+	    if ( lr->lr_binddn != NULL ) {
+		    sprintf( msg, "   pending bind DN: <%s>\n", lr->lr_binddn );
+		    ber_err_print( msg );
+	    }
+	}
+	LDAP_MUTEX_UNLOCK( ld, LDAP_REQ_LOCK );
+
+	ber_err_print( "** Response Queue:\n" );
+	LDAP_MUTEX_LOCK( ld, LDAP_RESP_LOCK );
+	if (( lm = ld->ld_responses ) == NULLMSG ) {
+		ber_err_print( "   Empty\n" );
+	}
+	for ( ; lm != NULLMSG; lm = lm->lm_next ) {
+                sprintf( msg, " * 0x%p - msgid %d,  type %d\n",
+                    lm, lm->lm_msgid, lm->lm_msgtype );
+		ber_err_print( msg );
+		if (( l = lm->lm_chain ) != NULL ) {
+			ber_err_print( "   chained responses:\n" );
+			for ( ; l != NULLMSG; l = l->lm_chain ) {
+				sprintf( msg,
+                                    "  * 0x%p - msgid %d,  type %d\n",
+                                    l, l->lm_msgid, l->lm_msgtype );
+				ber_err_print( msg );
+			}
+		}
+	}
+	LDAP_MUTEX_UNLOCK( ld, LDAP_RESP_LOCK );
+}
+#endif /* LDAP_DEBUG */
+
+
+LDAPRequest *
+nsldapi_new_request( LDAPConn *lc, BerElement *ber, int msgid, int expect_resp )
+{
+	LDAPRequest	*lr;
+
+	lr = (LDAPRequest *)NSLDAPI_CALLOC( 1, sizeof( LDAPRequest ));
+
+	if ( lr != NULL ) {
+		lr->lr_conn = lc;
+		lr->lr_ber = ber;
+		lr->lr_msgid = lr->lr_origid = msgid;
+		lr->lr_expect_resp = expect_resp;
+		lr->lr_status = LDAP_REQST_INPROGRESS;
+		lr->lr_res_errno = LDAP_SUCCESS;	/* optimistic */
+
+		if ( lc != NULL ) {	/* mark connection as in use */
+			++lc->lconn_refcnt;
+			lc->lconn_lastused = time( 0 );
+		}
+	}
+
+	return( lr );
+}
+
+
+void
+nsldapi_free_request( LDAP *ld, LDAPRequest *lr, int free_conn )
+{
+	LDAPRequest	*tmplr, *nextlr;
+
+	LDAPDebug( LDAP_DEBUG_TRACE,
+		"nsldapi_free_request 0x%p (origid %d, msgid %d)\n",
+		lr, lr->lr_origid, lr->lr_msgid );
+
+	if ( lr->lr_parent != NULL ) {
+		/* unlink child from parent */
+		lr->lr_parent->lr_child = NULL;
+		--lr->lr_parent->lr_outrefcnt;
+	}
+
+	if ( lr->lr_status == LDAP_REQST_WRITING ) {
+		--lr->lr_conn->lconn_pending_requests;
+	}
+
+	/* free all of our spawned referrals (child requests) */
+	for ( tmplr = lr->lr_child; tmplr != NULL; tmplr = nextlr ) {
+		nextlr = tmplr->lr_sibling;
+		nsldapi_free_request( ld, tmplr, free_conn );
+	}
+
+	if ( free_conn ) {
+		nsldapi_free_connection( ld, lr->lr_conn, NULL, NULL, 0, 1 );
+	}
+
+	if ( lr->lr_prev == NULL ) {
+		ld->ld_requests = lr->lr_next;
+	} else {
+		lr->lr_prev->lr_next = lr->lr_next;
+	}
+
+	if ( lr->lr_next != NULL ) {
+		lr->lr_next->lr_prev = lr->lr_prev;
+	}
+
+	if ( lr->lr_ber != NULL ) {
+		ber_free( lr->lr_ber, 1 );
+	}
+
+	if ( lr->lr_res_error != NULL ) {
+		NSLDAPI_FREE( lr->lr_res_error );
+	}
+
+	if ( lr->lr_res_matched != NULL ) {
+		NSLDAPI_FREE( lr->lr_res_matched );
+	}
+
+	if ( lr->lr_binddn != NULL ) {
+		NSLDAPI_FREE( lr->lr_binddn );
+	}
+
+	if ( lr->lr_res_ctrls != NULL ) {
+		ldap_controls_free( lr->lr_res_ctrls );
+	}
+	NSLDAPI_FREE( lr );
+}
+
+
+/*
+ * Add a request to the end of the list of outstanding requests.
+ * This function must be called with these two locks in hand, acquired in
+ * this order:
+ *	LDAP_CONN_LOCK
+ *	LDAP_REQ_LOCK
+ */
+void
+nsldapi_queue_request_nolock( LDAP *ld, LDAPRequest *lr )
+{
+        if ( NULL == ld->ld_requests ) {
+		ld->ld_requests = lr;
+        } else {
+                LDAPRequest     *tmplr;
+
+                for ( tmplr = ld->ld_requests; tmplr->lr_next != NULL;
+                                tmplr = tmplr->lr_next ) {
+                        ;
+                }
+                tmplr->lr_next = lr;
+                lr->lr_prev = tmplr;
+        }
+}
+
+
+static void
+free_servers( LDAPServer *srvlist )
+{
+    LDAPServer	*nextsrv;
+
+    while ( srvlist != NULL ) {
+	nextsrv = srvlist->lsrv_next;
+	if ( srvlist->lsrv_dn != NULL ) {
+		NSLDAPI_FREE( srvlist->lsrv_dn );
+	}
+	if ( srvlist->lsrv_host != NULL ) {
+		NSLDAPI_FREE( srvlist->lsrv_host );
+	}
+	NSLDAPI_FREE( srvlist );
+	srvlist = nextsrv;
+    }
+}
+
+
+/*
+ * Initiate chasing of LDAPv2+ (Umich extension) referrals.
+ *
+ * Returns an LDAP error code.
+ *
+ * Note that *hadrefp will be set to 1 if one or more referrals were found in
+ * "*errstrp" (even if we can't chase them) and zero if none were found.
+ * 
+ * XXX merging of errors in this routine needs to be improved.
+ */
+int
+nsldapi_chase_v2_referrals( LDAP *ld, LDAPRequest *lr, char **errstrp,
+    int *totalcountp, int *chasingcountp )
+{
+	char		*p, *ref, *unfollowed;
+	LDAPRequest	*origreq;
+	int		rc, tmprc, len, unknown;
+
+	LDAPDebug( LDAP_DEBUG_TRACE, "nsldapi_chase_v2_referrals\n", 0, 0, 0 );
+
+	*totalcountp = *chasingcountp = 0;
+
+	if ( *errstrp == NULL ) {
+		return( LDAP_SUCCESS );
+	}
+
+	len = strlen( *errstrp );
+	for ( p = *errstrp; len >= LDAP_REF_STR_LEN; ++p, --len ) {
+		if (( *p == 'R' || *p == 'r' ) && strncasecmp( p,
+		    LDAP_REF_STR, LDAP_REF_STR_LEN ) == 0 ) {
+			*p = '\0';
+			p += LDAP_REF_STR_LEN;
+			break;
+		}
+	}
+
+	if ( len < LDAP_REF_STR_LEN ) {
+		return( LDAP_SUCCESS );
+	}
+
+	if ( lr->lr_parentcnt >= ld->ld_refhoplimit ) {
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "more than %d referral hops (dropping)\n",
+		    ld->ld_refhoplimit, 0, 0 );
+		return( LDAP_REFERRAL_LIMIT_EXCEEDED );
+	}
+
+	/* find original request */
+	for ( origreq = lr; origreq->lr_parent != NULL;
+	     origreq = origreq->lr_parent ) {
+		;
+	}
+
+	unfollowed = NULL;
+	rc = LDAP_SUCCESS;
+
+	/* parse out & follow referrals */
+	for ( ref = p; rc == LDAP_SUCCESS && ref != NULL; ref = p ) {
+		if (( p = strchr( ref, '\n' )) != NULL ) {
+			*p++ = '\0';
+		} else {
+			p = NULL;
+		}
+
+		++*totalcountp;
+
+		rc = chase_one_referral( ld, lr, origreq, ref, "v2 referral",
+		    &unknown, 0 /* not a reference */ );
+
+		if ( rc != LDAP_SUCCESS || unknown ) {
+			if (( tmprc = nsldapi_append_referral( ld, &unfollowed,
+			    ref )) != LDAP_SUCCESS ) {
+				rc = tmprc;
+			}
+		} else {
+			++*chasingcountp;
+		}
+	}
+
+	NSLDAPI_FREE( *errstrp );
+	*errstrp = unfollowed;
+
+	return( rc );
+}
+
+
+/* returns an LDAP error code */
+int
+nsldapi_chase_v3_refs( LDAP *ld, LDAPRequest *lr, char **v3refs,
+    int is_reference, int *totalcountp, int *chasingcountp )
+{
+   	int		rc = LDAP_SUCCESS;
+	int		i, unknown;
+	LDAPRequest	*origreq;
+
+	*totalcountp = *chasingcountp = 0;
+
+	if ( v3refs == NULL || v3refs[0] == NULL ) {
+		return( LDAP_SUCCESS );
+	}
+
+	*totalcountp = 1;
+
+	if ( lr->lr_parentcnt >= ld->ld_refhoplimit ) {
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "more than %d referral hops (dropping)\n",
+		    ld->ld_refhoplimit, 0, 0 );
+		return( LDAP_REFERRAL_LIMIT_EXCEEDED );
+	}
+
+	/* find original request */
+	for ( origreq = lr; origreq->lr_parent != NULL;
+	    origreq = origreq->lr_parent ) {
+		;
+	}
+
+	/*
+	 * in LDAPv3, we just need to follow one referral in the set.
+	 * we dp this by stopping as soon as we succeed in initiating a
+	 * chase on any referral (basically this means we were able to connect
+	 * to the server and bind).
+	 */
+	for ( i = 0; v3refs[i] != NULL; ++i ) {
+		rc = chase_one_referral( ld, lr, origreq, v3refs[i],
+		    is_reference ? "v3 reference" : "v3 referral", &unknown,
+		    is_reference );
+		if ( rc == LDAP_SUCCESS && !unknown ) {
+			*chasingcountp = 1;
+			break;
+		}
+	}
+
+	/* XXXmcs: should we save unfollowed referrals somewhere? */
+
+	return( rc );	/* last error is as good as any other I guess... */
+}
+
+
+/*
+ * returns an LDAP error code
+ *
+ * XXXmcs: this function used to have #ifdef LDAP_DNS code in it but I
+ *	removed it when I improved the parsing (we don't define LDAP_DNS
+ *	here at Netscape).
+ */
+static int
+chase_one_referral( LDAP *ld, LDAPRequest *lr, LDAPRequest *origreq,
+    char *refurl, char *desc, int *unknownp, int is_reference )
+{
+	int		rc, tmprc, secure, msgid;
+	LDAPServer	*srv;
+	BerElement	*ber;
+	LDAPURLDesc	*ludp;
+
+	*unknownp = 0;
+	ludp = NULLLDAPURLDESC;
+
+	if ( nsldapi_url_parse( refurl, &ludp, 0 ) != 0 ) {
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "ignoring unknown %s <%s>\n", desc, refurl, 0 );
+		*unknownp = 1;
+		rc = LDAP_SUCCESS;
+		goto cleanup_and_return;
+	}
+
+	secure = (( ludp->lud_options & LDAP_URL_OPT_SECURE ) != 0 );
+
+/* XXXmcs: can't tell if secure is supported by connect callback */
+	if ( secure && ld->ld_extconnect_fn == NULL ) {
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "ignoring LDAPS %s <%s>\n", desc, refurl, 0 );
+		*unknownp = 1;
+		rc = LDAP_SUCCESS;
+		goto cleanup_and_return;
+	}
+
+	LDAPDebug( LDAP_DEBUG_TRACE, "chasing LDAP%s %s: <%s>\n",
+	    secure ? "S" : "", desc, refurl );
+
+	LDAP_MUTEX_LOCK( ld, LDAP_MSGID_LOCK );
+	msgid = ++ld->ld_msgid;
+	LDAP_MUTEX_UNLOCK( ld, LDAP_MSGID_LOCK );
+
+	if (( tmprc = re_encode_request( ld, origreq->lr_ber, msgid,
+	    ludp, &ber, is_reference )) != LDAP_SUCCESS ) {
+		rc = tmprc;
+		goto cleanup_and_return;
+	}
+
+	if (( srv = (LDAPServer *)NSLDAPI_CALLOC( 1, sizeof( LDAPServer )))
+	    == NULL ) {
+		ber_free( ber, 1 );
+		rc = LDAP_NO_MEMORY;
+		goto cleanup_and_return;
+	}
+
+	if ( ludp->lud_host == NULL && ld->ld_defhost == NULL ) {
+		srv->lsrv_host = NULL;
+	} else {
+		if ( ludp->lud_host == NULL ) {
+		  srv->lsrv_host =
+		    nsldapi_strdup( origreq->lr_conn->lconn_server->lsrv_host );
+		  LDAPDebug( LDAP_DEBUG_TRACE,
+		    "chase_one_referral: using hostname '%s' from original "
+		    "request on new request\n",
+		    srv->lsrv_host, 0, 0);
+		} else {
+		  srv->lsrv_host = nsldapi_strdup( ludp->lud_host );
+		  LDAPDebug( LDAP_DEBUG_TRACE,
+		    "chase_one_referral: using hostname '%s' as specified "
+		    "on new request\n",
+		    srv->lsrv_host, 0, 0);
+		}
+
+		if ( srv->lsrv_host == NULL ) {
+			NSLDAPI_FREE( (char *)srv );
+			ber_free( ber, 1 );
+			rc = LDAP_NO_MEMORY;
+			goto cleanup_and_return;
+		}
+	}
+
+	if ( ludp->lud_port == 0 && ludp->lud_host == NULL ) {
+		srv->lsrv_port = origreq->lr_conn->lconn_server->lsrv_port;
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "chase_one_referral: using port (%d) from original "
+		    "request on new request\n",
+		    srv->lsrv_port, 0, 0);
+	} else if ( ludp->lud_port != 0 ) {
+		srv->lsrv_port = ludp->lud_port;
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "chase_one_referral: using port (%d) as specified on "
+		    "new request\n",
+		    srv->lsrv_port, 0, 0);
+	} else {
+		srv->lsrv_port = secure ? LDAPS_PORT : LDAP_PORT;
+		LDAPDebug( LDAP_DEBUG_TRACE,
+		    "chase_one_referral: using default port (%d)\n",
+			srv->lsrv_port, 0, 0 );
+	}
+
+	if ( secure ) {
+		srv->lsrv_options |= LDAP_SRV_OPT_SECURE;
+	}
+
+	if ( nsldapi_send_server_request( ld, ber, msgid,
+	    lr, srv, NULL, NULL, 1 ) < 0 ) {
+		rc = LDAP_GET_LDERRNO( ld, NULL, NULL );
+		LDAPDebug( LDAP_DEBUG_ANY, "Unable to chase %s %s (%s)\n",
+		    desc, refurl, ldap_err2string( rc ));
+	} else {
+		rc = LDAP_SUCCESS;
+	}
+
+cleanup_and_return:
+	if ( ludp != NULLLDAPURLDESC ) {
+		ldap_free_urldesc( ludp );
+	}
+
+	return( rc );
+}
+
+
+/* returns an LDAP error code */
+int
+nsldapi_append_referral( LDAP *ld, char **referralsp, char *s )
+{
+	int	first;
+
+	if ( *referralsp == NULL ) {
+		first = 1;
+		*referralsp = (char *)NSLDAPI_MALLOC( strlen( s ) +
+		    LDAP_REF_STR_LEN + 1 );
+	} else {
+		first = 0;
+		*referralsp = (char *)NSLDAPI_REALLOC( *referralsp,
+		    strlen( *referralsp ) + strlen( s ) + 2 );
+	}
+
+	if ( *referralsp == NULL ) {
+		return( LDAP_NO_MEMORY );
+	}
+
+	if ( first ) {
+		strcpy( *referralsp, LDAP_REF_STR );
+	} else {
+		strcat( *referralsp, "\n" );
+	}
+	strcat( *referralsp, s );
+
+	return( LDAP_SUCCESS );
+}
+
+
+
+/* returns an LDAP error code */
+static int
+re_encode_request( LDAP *ld, BerElement *origber, int msgid, LDAPURLDesc *ludp,
+    BerElement **berp, int is_reference )
+{
+/*
+ * XXX this routine knows way too much about how the lber library works!
+ */
+	ber_int_t origmsgid;
+	ber_tag_t tag;
+	ber_int_t ver;
+	int			rc;
+	BerElement		*ber;
+	struct berelement	tmpber;
+	char			*dn, *orig_dn;
+	/* extra stuff for search request */
+	ber_int_t scope = -1;
+
+	LDAPDebug( LDAP_DEBUG_TRACE,
+	    "re_encode_request: new msgid %d, new dn <%s>\n",
+	    msgid, ( ludp->lud_dn == NULL ) ? "NONE" : ludp->lud_dn, 0 );
+
+	tmpber = *origber;
+
+	/*
+	 * All LDAP requests are sequences that start with a message id.  For
+	 * everything except delete requests, this is followed by a sequence
+	 * that is tagged with the operation code.  For deletes, there is just
+	 * a DN that is tagged with the operation code.
+	 */
+
+	/* skip past msgid and get operation tag */
+	if ( ber_scanf( &tmpber, "{it", &origmsgid, &tag ) == LBER_ERROR ) {
+		return( LDAP_DECODING_ERROR );
+	}
+
+	/*
+	 * XXXmcs: we don't support filters in search referrals yet,
+	 * so if present we return an error which is probably
+	 * better than just ignoring the extra info.
+	 * XXXrichm: we now support scopes.  Supporting filters would require
+	 * a lot more additional work to be able to read the filter from
+	 * the ber original search request, convert to string, etc.  It might
+	 * be better and easier to change nsldapi_build_search_req to have
+	 * some special mode by which you could tell it to skip filter and
+	 * attrlist encoding if no filter was given - then we could just
+	 * create a new ber search request with our new filter if present.
+	 */
+	if ( ( tag == LDAP_REQ_SEARCH ) && ( ludp->lud_filter != NULL )) {
+		return( LDAP_LOCAL_ERROR );
+	}
+
+	if ( tag == LDAP_REQ_BIND ) {
+		/* bind requests have a version number before the DN */
+		rc = ber_scanf( &tmpber, "{ia", &ver, &orig_dn );
+	} else if ( tag == LDAP_REQ_DELETE ) {
+		/* delete requests DNs are not within a sequence */
+		rc = ber_scanf( &tmpber, "a", &orig_dn );
+	} else if ( tag == LDAP_REQ_SEARCH ) {
+	    /* need scope */
+	    rc = ber_scanf( &tmpber, "{ae", &orig_dn, &scope );
+	} else {
+	    rc = ber_scanf( &tmpber, "{a", &orig_dn );
+	}
+
+	if ( rc == LBER_ERROR ) {
+	    return( LDAP_DECODING_ERROR );
+	}
+
+	if ( ludp->lud_dn == NULL ) {
+	    dn = orig_dn;
+	} else {
+	    dn = ludp->lud_dn;
+	    NSLDAPI_FREE( orig_dn );
+	    orig_dn = NULL;
+	}
+
+	if ( ludp->lud_scope != -1 ) {
+	    scope = ludp->lud_scope; /* scope provided by ref - use it */
+	} else if (is_reference) {
+	    /* 
+	     * RFC 4511 says that the we should use scope BASE in the
+	     * search reference if the client's original request was for scope
+	     * ONELEVEL - since the server did not include the scope in the 
+	     * search reference returned, we must provide the correct behavior
+	     * in the client (i.e. the correct behavior is implied)
+	     * see RFC 4511 section 4.5.3 for more information
+	     */
+	    if (scope == LDAP_SCOPE_ONELEVEL) {
+		scope = LDAP_SCOPE_BASE;
+	    }
+	}
+
+	/* allocate and build the new request */
+	if (( rc = nsldapi_alloc_ber_with_options( ld, &ber ))
+	    != LDAP_SUCCESS ) {
+		if ( orig_dn != NULL ) {
+			NSLDAPI_FREE( orig_dn );
+		}
+		return( rc );
+	}
+
+	if ( tag == LDAP_REQ_BIND ) {
+		rc = ber_printf( ber, "{it{is", msgid, tag, ver , dn );
+	} else if ( tag == LDAP_REQ_DELETE ) {
+	    rc = ber_printf( ber, "{its}", msgid, tag, dn );
+	} else if ( tag == LDAP_REQ_SEARCH ) {
+	    rc = ber_printf( ber, "{it{se", msgid, tag, dn, scope );
+	} else {
+	    rc = ber_printf( ber, "{it{s", msgid, tag, dn );
+	}
+
+	if ( orig_dn != NULL ) {
+		NSLDAPI_FREE( orig_dn );
+	}
+/*
+ * can't use "dn" or "orig_dn" from this point on (they've been freed)
+ */
+
+	if ( rc == -1 ) {
+		ber_free( ber, 1 );
+		return( LDAP_ENCODING_ERROR );
+	}
+
+	if ( tag != LDAP_REQ_DELETE &&
+	    ( ber_write( ber, tmpber.ber_ptr, ( tmpber.ber_end -
+	    tmpber.ber_ptr ), 0 ) != ( tmpber.ber_end - tmpber.ber_ptr )
+	    || ber_printf( ber, "}}" ) == -1 )) {
+		ber_free( ber, 1 );
+		return( LDAP_ENCODING_ERROR );
+	}
+
+#ifdef LDAP_DEBUG
+	if ( ldap_debug & LDAP_DEBUG_PACKETS ) {
+		LDAPDebug( LDAP_DEBUG_ANY, "re_encode_request new request is:\n",
+		    0, 0, 0 );
+		ber_dump( ber, 0 );
+	}
+#endif /* LDAP_DEBUG */
+
+	*berp = ber;
+	return( LDAP_SUCCESS );
+}
+
+
+LDAPRequest *
+nsldapi_find_request_by_msgid( LDAP *ld, int msgid )
+{
+    	LDAPRequest	*lr;
+
+	for ( lr = ld->ld_requests; lr != NULL; lr = lr->lr_next ) {
+		if ( msgid == lr->lr_msgid ) {
+			break;
+		}
+	}
+
+	return( lr );
+}
+
+
+/*
+ * nsldapi_connection_lost_nolock() resets "ld" to a non-connected, known
+ * state.  It should be called whenever a fatal error occurs on the
+ * Sockbuf "sb."  sb == NULL means we don't know specifically where
+ * the problem was so we assume all connections are bad.
+ */
+void
+nsldapi_connection_lost_nolock( LDAP *ld, Sockbuf *sb )
+{
+	LDAPRequest	*lr;
+
+	/*
+	 * change status of all pending requests that are associated with "sb
+	 *	to "connection dead."
+	 * also change the connection status to "dead" and remove it from
+	 *	the list of sockets we are interested in.
+	 */
+	for ( lr = ld->ld_requests; lr != NULL; lr = lr->lr_next ) {
+		if ( sb == NULL ||
+		    ( lr->lr_conn != NULL && lr->lr_conn->lconn_sb == sb )) {
+			lr->lr_status = LDAP_REQST_CONNDEAD;
+			if ( lr->lr_conn != NULL ) {
+				lr->lr_conn->lconn_status = LDAP_CONNST_DEAD;
+				nsldapi_iostatus_interest_clear( ld,
+				    lr->lr_conn->lconn_sb );
+			}
+		}
+	}
+}
+
+
+#ifdef LDAP_DNS
+static LDAPServer *
+dn2servers( LDAP *ld, char *dn )	/* dn can also be a domain.... */
+{
+	char		*p, *domain, *host, *server_dn, **dxs;
+	int		i, port;
+	LDAPServer	*srvlist, *prevsrv, *srv;
+
+	if (( domain = strrchr( dn, '@' )) != NULL ) {
+		++domain;
+	} else {
+		domain = dn;
+	}
+
+	if (( dxs = nsldapi_getdxbyname( domain )) == NULL ) {
+		LDAP_SET_LDERRNO( ld, LDAP_NO_MEMORY, NULL, NULL );
+		return( NULL );
+	}
+
+	srvlist = NULL;
+
+	for ( i = 0; dxs[ i ] != NULL; ++i ) {
+		port = LDAP_PORT;
+		server_dn = NULL;
+		if ( strchr( dxs[ i ], ':' ) == NULL ) {
+			host = dxs[ i ];
+		} else if ( strlen( dxs[ i ] ) >= 7 &&
+		    strncmp( dxs[ i ], "ldap://", 7 ) == 0 ) {
+			host = dxs[ i ] + 7;
+			if (( p = strchr( host, ':' )) == NULL ) {
+				p = host;
+			} else {
+				*p++ = '\0';
+				port = atoi( p );
+			}
+			if (( p = strchr( p, '/' )) != NULL ) {
+				server_dn = ++p;
+				if ( *server_dn == '\0' ) {
+					server_dn = NULL;
+				}
+			}
+		} else {
+			host = NULL;
+		}
+
+		if ( host != NULL ) {	/* found a server we can use */
+			if (( srv = (LDAPServer *)NSLDAPI_CALLOC( 1,
+			    sizeof( LDAPServer ))) == NULL ) {
+				free_servers( srvlist );
+				srvlist = NULL;
+				break;		/* exit loop & return */
+			}
+
+			/* add to end of list of servers */
+			if ( srvlist == NULL ) {
+				srvlist = srv;
+			} else {
+				prevsrv->lsrv_next = srv;
+			}
+			prevsrv = srv;
+			
+			/* copy in info. */
+			if (( srv->lsrv_host = nsldapi_strdup( host )) == NULL
+			    || ( server_dn != NULL && ( srv->lsrv_dn =
+			    nsldapi_strdup( server_dn )) == NULL )) {
+				free_servers( srvlist );
+				srvlist = NULL;
+				break;		/* exit loop & return */
+			}
+			srv->lsrv_port = port;
+		}
+	}
+
+	ldap_value_free( dxs );
+
+	if ( srvlist == NULL ) {
+		LDAP_SET_LDERRNO( ld, LDAP_SERVER_DOWN, NULL, NULL );
+	}
+
+	return( srvlist );
+}
+#endif /* LDAP_DNS */