Adding upstream version 2.4.57+dfsg.upstream/2.4.57+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

18 files changed, 1742 insertions, 0 deletions

diff --git a/servers/slapd/back-sock/Makefile.in b/servers/slapd/back-sock/Makefile.in
new file mode 100644
index 0000000..bb4e94f
--- /dev/null
+++ b/servers/slapd/back-sock/Makefile.in
@@ -0,0 +1,47 @@
+# Makefile.in for back-sock
+# $OpenLDAP$
+## This work is part of OpenLDAP Software <http://www.openldap.org/>.
+##
+## Copyright 2007-2021 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 Brian Candler for inclusion
+## in OpenLDAP Software.
+
+SRCS	= init.c config.c opensock.c search.c bind.c unbind.c add.c \
+		delete.c modify.c modrdn.c compare.c result.c extended.c
+OBJS	= init.lo config.lo opensock.lo search.lo bind.lo unbind.lo add.lo \
+		delete.lo modify.lo modrdn.lo compare.lo result.lo extended.lo
+
+LDAP_INCDIR= ../../../include       
+LDAP_LIBDIR= ../../../libraries
+
+BUILD_OPT = "--enable-sock"
+BUILD_MOD = @BUILD_SOCK@
+
+mod_DEFS = -DSLAPD_IMPORT
+MOD_DEFS = $(@BUILD_SOCK@_DEFS)
+
+shared_LDAP_LIBS = $(LDAP_LIBLDAP_R_LA) $(LDAP_LIBLBER_LA)
+NT_LINK_LIBS = -L.. -lslapd $(@BUILD_LIBS_DYNAMIC@_LDAP_LIBS)
+UNIX_LINK_LIBS = $(@BUILD_LIBS_DYNAMIC@_LDAP_LIBS)
+
+LIBBASE = back_sock
+
+XINCPATH = -I.. -I$(srcdir)/..
+XDEFS = $(MODULES_CPPFLAGS)
+
+all-local-lib:	../.backend
+
+../.backend: lib$(LIBBASE).a
+	@touch $@
+
diff --git a/servers/slapd/back-sock/add.c b/servers/slapd/back-sock/add.c
new file mode 100644
index 0000000..c86c8a9
--- /dev/null
+++ b/servers/slapd/back-sock/add.c
@@ -0,0 +1,69 @@
+/* add.c - sock backend add function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+int
+sock_back_add(
+    Operation	*op,
+    SlapReply	*rs )
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	AttributeDescription *entry = slap_schema.si_ad_entry;
+	FILE			*fp;
+	int			len;
+
+	if ( ! access_allowed( op, op->oq_add.rs_e,
+		entry, NULL, ACL_WADD, NULL ) )
+	{
+		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
+		return -1;
+	}
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the add process */
+	fprintf( fp, "ADD\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	ldap_pvt_thread_mutex_lock( &entry2str_mutex );
+	fprintf( fp, "%s", entry2str( op->oq_add.rs_e, &len ) );
+	ldap_pvt_thread_mutex_unlock( &entry2str_mutex );
+	fprintf (fp, "\n" );
+
+	/* read in the result and send it along */
+	sock_read_and_send_results( op, rs, fp );
+
+	fclose( fp );
+	return( 0 );
+}
diff --git a/servers/slapd/back-sock/back-sock.h b/servers/slapd/back-sock/back-sock.h
new file mode 100644
index 0000000..68abca8
--- /dev/null
+++ b/servers/slapd/back-sock/back-sock.h
@@ -0,0 +1,61 @@
+/* sock.h - socket backend header file */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#ifndef SLAPD_SOCK_H
+#define SLAPD_SOCK_H
+
+#include "proto-sock.h"
+
+LDAP_BEGIN_DECL
+
+struct sockinfo {
+	const char	*si_sockpath;
+	slap_mask_t	si_extensions;
+	slap_mask_t	si_ops;		/* overlay: operations to act on */
+	slap_mask_t	si_resps;	/* overlay: responses to forward */
+	regex_t	si_dnpat;		/* overlay: DN pattern to match */
+	struct berval 	si_dnpatstr;
+};
+
+#define	SOCK_EXT_BINDDN	1
+#define	SOCK_EXT_PEERNAME	2
+#define	SOCK_EXT_SSF		4
+#define	SOCK_EXT_CONNID		8
+
+extern FILE *opensock LDAP_P((
+	const char *sockpath));
+
+extern void sock_print_suffixes LDAP_P((
+	FILE *fp,
+	BackendDB *bd));
+
+extern void sock_print_conn LDAP_P((
+	FILE *fp,
+	Connection *conn,
+	struct sockinfo *si));
+
+extern int sock_read_and_send_results LDAP_P((
+	Operation *op,
+	SlapReply *rs,
+	FILE *fp));
+
+LDAP_END_DECL
+
+#endif
diff --git a/servers/slapd/back-sock/bind.c b/servers/slapd/back-sock/bind.c
new file mode 100644
index 0000000..83982bf
--- /dev/null
+++ b/servers/slapd/back-sock/bind.c
@@ -0,0 +1,80 @@
+/* bind.c - sock backend bind function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/socket.h>
+#include <ac/string.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+int
+sock_back_bind(
+    Operation		*op,
+    SlapReply		*rs )
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	AttributeDescription *entry = slap_schema.si_ad_entry;
+	Entry e;
+	FILE			*fp;
+	int			rc;
+
+	e.e_id = NOID;
+	e.e_name = op->o_req_dn;
+	e.e_nname = op->o_req_ndn;
+	e.e_attrs = NULL;
+	e.e_ocflags = 0;
+	e.e_bv.bv_len = 0;
+	e.e_bv.bv_val = NULL;
+	e.e_private = NULL;
+
+	if ( ! access_allowed( op, &e,
+		entry, NULL, ACL_AUTH, NULL ) )
+	{
+		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
+		return -1;
+	}
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the bind process */
+	fprintf( fp, "BIND\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "dn: %s\n", op->o_req_dn.bv_val );
+	fprintf( fp, "method: %d\n", op->oq_bind.rb_method );
+	fprintf( fp, "credlen: %lu\n", op->oq_bind.rb_cred.bv_len );
+	fprintf( fp, "cred: %s\n", op->oq_bind.rb_cred.bv_val ); /* XXX */
+	fprintf( fp, "\n" );
+
+	/* read in the results and send them along */
+	rc = sock_read_and_send_results( op, rs, fp );
+	fclose( fp );
+
+	return( rc );
+}
diff --git a/servers/slapd/back-sock/compare.c b/servers/slapd/back-sock/compare.c
new file mode 100644
index 0000000..72ead88
--- /dev/null
+++ b/servers/slapd/back-sock/compare.c
@@ -0,0 +1,88 @@
+/* compare.c - sock backend compare function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 1998-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+
+#include "slap.h"
+#include "back-sock.h"
+#include "ldif.h"
+
+int
+sock_back_compare(
+    Operation	*op,
+    SlapReply	*rs )
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	AttributeDescription *entry = slap_schema.si_ad_entry;
+	Entry e;
+	FILE			*fp;
+	char *text;
+
+	e.e_id = NOID;
+	e.e_name = op->o_req_dn;
+	e.e_nname = op->o_req_ndn;
+	e.e_attrs = NULL;
+	e.e_ocflags = 0;
+	e.e_bv.bv_len = 0;
+	e.e_bv.bv_val = NULL;
+	e.e_private = NULL;
+
+	if ( ! access_allowed( op, &e,
+		entry, NULL, ACL_COMPARE, NULL ) )
+	{
+		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
+		return -1;
+	}
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the compare process */
+	fprintf( fp, "COMPARE\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "dn: %s\n", op->o_req_dn.bv_val );
+	/* could be binary */
+	text = ldif_put_wrap( LDIF_PUT_VALUE,
+		op->orc_ava->aa_desc->ad_cname.bv_val,
+		op->orc_ava->aa_value.bv_val,
+		op->orc_ava->aa_value.bv_len, LDIF_LINE_WIDTH_MAX );
+	if ( text ) {
+		fprintf( fp, "%s\n", text );
+		ber_memfree( text );
+	} else {
+		fprintf( fp, "\n\n" );
+	}
+
+	/* read in the result and send it along */
+	sock_read_and_send_results( op, rs, fp );
+
+	fclose( fp );
+	return( 0 );
+}
diff --git a/servers/slapd/back-sock/config.c b/servers/slapd/back-sock/config.c
new file mode 100644
index 0000000..a340239
--- /dev/null
+++ b/servers/slapd/back-sock/config.c
@@ -0,0 +1,420 @@
+/* config.c - sock backend configuration file routine */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software. Dynamic config support by Howard Chu.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+
+#include "slap.h"
+#include "config.h"
+#include "back-sock.h"
+
+static ConfigDriver bs_cf_gen;
+static int sock_over_setup();
+static slap_response sock_over_response;
+
+enum {
+	BS_EXT = 1,
+	BS_OPS,
+	BS_RESP,
+	BS_DNPAT
+};
+
+/* The number of overlay-only config attrs */
+#define NUM_OV_ATTRS	3
+
+static ConfigTable bscfg[] = {
+	{ "sockops", "ops", 2, 0, 0, ARG_MAGIC|BS_OPS,
+		bs_cf_gen, "( OLcfgDbAt:7.3 NAME 'olcOvSocketOps' "
+			"DESC 'Operation types to forward' "
+			"EQUALITY caseIgnoreMatch "
+			"SYNTAX OMsDirectoryString )", NULL, NULL },
+	{ "sockresps", "resps", 2, 0, 0, ARG_MAGIC|BS_RESP,
+		bs_cf_gen, "( OLcfgDbAt:7.4 NAME 'olcOvSocketResps' "
+			"DESC 'Response types to forward' "
+			"EQUALITY caseIgnoreMatch "
+			"SYNTAX OMsDirectoryString )", NULL, NULL },
+	{ "sockdnpat", "regexp", 2, 2, 0, ARG_MAGIC|BS_DNPAT,
+		bs_cf_gen, "( OLcfgDbAt:7.5 NAME 'olcOvSocketDNpat' "
+			"DESC 'DN pattern to match' "
+			"EQUALITY caseIgnoreMatch "
+			"SYNTAX OMsDirectoryString SINGLE-VALUE )", NULL, NULL },
+
+	{ "socketpath", "pathname", 2, 2, 0, ARG_STRING|ARG_OFFSET,
+		(void *)offsetof(struct sockinfo, si_sockpath),
+		"( OLcfgDbAt:7.1 NAME 'olcDbSocketPath' "
+			"DESC 'Pathname for Unix domain socket' "
+			"EQUALITY caseExactMatch "
+			"SYNTAX OMsDirectoryString SINGLE-VALUE )", NULL, NULL },
+	{ "extensions", "ext", 2, 0, 0, ARG_MAGIC|BS_EXT,
+		bs_cf_gen, "( OLcfgDbAt:7.2 NAME 'olcDbSocketExtensions' "
+			"DESC 'binddn, peername, or ssf' "
+			"EQUALITY caseIgnoreMatch "
+			"SYNTAX OMsDirectoryString )", NULL, NULL },
+	{ NULL, NULL }
+};
+
+static ConfigOCs bsocs[] = {
+	{ "( OLcfgDbOc:7.1 "
+		"NAME 'olcDbSocketConfig' "
+		"DESC 'Socket backend configuration' "
+		"SUP olcDatabaseConfig "
+		"MUST olcDbSocketPath "
+		"MAY olcDbSocketExtensions )",
+			Cft_Database, bscfg+NUM_OV_ATTRS },
+	{ NULL, 0, NULL }
+};
+
+static ConfigOCs osocs[] = {
+	{ "( OLcfgDbOc:7.2 "
+		"NAME 'olcOvSocketConfig' "
+		"DESC 'Socket overlay configuration' "
+		"SUP olcOverlayConfig "
+		"MUST olcDbSocketPath "
+		"MAY ( olcDbSocketExtensions $ "
+			" olcOvSocketOps $ olcOvSocketResps $ "
+			" olcOvSocketDNpat ) )",
+			Cft_Overlay, bscfg },
+	{ NULL, 0, NULL }
+};
+
+#define SOCK_OP_BIND	0x001
+#define SOCK_OP_UNBIND	0x002
+#define SOCK_OP_SEARCH	0x004
+#define SOCK_OP_COMPARE	0x008
+#define SOCK_OP_MODIFY	0x010
+#define SOCK_OP_MODRDN	0x020
+#define SOCK_OP_ADD		0x040
+#define SOCK_OP_DELETE	0x080
+#define SOCK_OP_EXTENDED	0x100
+
+#define SOCK_REP_RESULT	0x001
+#define SOCK_REP_SEARCH	0x002
+
+static slap_verbmasks bs_exts[] = {
+	{ BER_BVC("binddn"), SOCK_EXT_BINDDN },
+	{ BER_BVC("peername"), SOCK_EXT_PEERNAME },
+	{ BER_BVC("ssf"), SOCK_EXT_SSF },
+	{ BER_BVC("connid"), SOCK_EXT_CONNID },
+	{ BER_BVNULL, 0 }
+};
+
+static slap_verbmasks ov_ops[] = {
+	{ BER_BVC("bind"), SOCK_OP_BIND },
+	{ BER_BVC("unbind"), SOCK_OP_UNBIND },
+	{ BER_BVC("search"), SOCK_OP_SEARCH },
+	{ BER_BVC("compare"), SOCK_OP_COMPARE },
+	{ BER_BVC("modify"), SOCK_OP_MODIFY },
+	{ BER_BVC("modrdn"), SOCK_OP_MODRDN },
+	{ BER_BVC("add"), SOCK_OP_ADD },
+	{ BER_BVC("delete"), SOCK_OP_DELETE },
+	{ BER_BVC("extended"), SOCK_OP_EXTENDED },
+	{ BER_BVNULL, 0 }
+};
+
+static slap_verbmasks ov_resps[] = {
+	{ BER_BVC("result"), SOCK_REP_RESULT },
+	{ BER_BVC("search"), SOCK_REP_SEARCH },
+	{ BER_BVNULL, 0 }
+};
+
+static int
+bs_cf_gen( ConfigArgs *c )
+{
+	struct sockinfo	*si;
+	int rc;
+
+	if ( c->be && c->table == Cft_Database )
+		si = c->be->be_private;
+	else if ( c->bi )
+		si = c->bi->bi_private;
+	else
+		return ARG_BAD_CONF;
+
+	if ( c->op == SLAP_CONFIG_EMIT ) {
+		switch( c->type ) {
+		case BS_EXT:
+			return mask_to_verbs( bs_exts, si->si_extensions, &c->rvalue_vals );
+		case BS_OPS:
+			return mask_to_verbs( ov_ops, si->si_ops, &c->rvalue_vals );
+		case BS_RESP:
+			return mask_to_verbs( ov_resps, si->si_resps, &c->rvalue_vals );
+		case BS_DNPAT:
+			value_add_one( &c->rvalue_vals, &si->si_dnpatstr );
+			return 0;
+		}
+	} else if ( c->op == LDAP_MOD_DELETE ) {
+		switch( c->type ) {
+		case BS_EXT:
+			if ( c->valx < 0 ) {
+				si->si_extensions = 0;
+				rc = 0;
+			} else {
+				slap_mask_t dels = 0;
+				rc = verbs_to_mask( c->argc, c->argv, bs_exts, &dels );
+				if ( rc == 0 )
+					si->si_extensions ^= dels;
+			}
+			return rc;
+		case BS_OPS:
+			if ( c->valx < 0 ) {
+				si->si_ops = 0;
+				rc = 0;
+			} else {
+				slap_mask_t dels = 0;
+				rc = verbs_to_mask( c->argc, c->argv, ov_ops, &dels );
+				if ( rc == 0 )
+					si->si_ops ^= dels;
+			}
+			return rc;
+		case BS_RESP:
+			if ( c->valx < 0 ) {
+				si->si_resps = 0;
+				rc = 0;
+			} else {
+				slap_mask_t dels = 0;
+				rc = verbs_to_mask( c->argc, c->argv, ov_resps, &dels );
+				if ( rc == 0 )
+					si->si_resps ^= dels;
+			}
+			return rc;
+		case BS_DNPAT:
+			regfree( &si->si_dnpat );
+			ch_free( si->si_dnpatstr.bv_val );
+			BER_BVZERO( &si->si_dnpatstr );
+			return 0;
+		}
+
+	} else {
+		switch( c->type ) {
+		case BS_EXT:
+			return verbs_to_mask( c->argc, c->argv, bs_exts, &si->si_extensions );
+		case BS_OPS:
+			return verbs_to_mask( c->argc, c->argv, ov_ops, &si->si_ops );
+		case BS_RESP:
+			return verbs_to_mask( c->argc, c->argv, ov_resps, &si->si_resps );
+		case BS_DNPAT:
+			if ( !regcomp( &si->si_dnpat, c->argv[1], REG_EXTENDED|REG_ICASE|REG_NOSUB )) {
+				ber_str2bv( c->argv[1], 0, 1, &si->si_dnpatstr );
+				return 0;
+			} else {
+				return 1;
+			}
+		}
+	}
+	return 1;
+}
+
+int
+sock_back_init_cf( BackendInfo *bi )
+{
+	int rc;
+	bi->bi_cf_ocs = bsocs;
+
+	rc = config_register_schema( bscfg, bsocs );
+	if ( !rc )
+		rc = sock_over_setup();
+	return rc;
+}
+
+/* sock overlay wrapper */
+static slap_overinst sockover;
+
+static int sock_over_db_init( Backend *be, struct config_reply_s *cr );
+static int sock_over_db_destroy( Backend *be, struct config_reply_s *cr );
+
+static BI_op_bind *sockfuncs[] = {
+	sock_back_bind,
+	sock_back_unbind,
+	sock_back_search,
+	sock_back_compare,
+	sock_back_modify,
+	sock_back_modrdn,
+	sock_back_add,
+	sock_back_delete,
+	0,                    /* abandon not supported */
+	sock_back_extended
+};
+
+static const int sockopflags[] = {
+	SOCK_OP_BIND,
+	SOCK_OP_UNBIND,
+	SOCK_OP_SEARCH,
+	SOCK_OP_COMPARE,
+	SOCK_OP_MODIFY,
+	SOCK_OP_MODRDN,
+	SOCK_OP_ADD,
+	SOCK_OP_DELETE,
+	0,                    /* abandon not supported */
+	SOCK_OP_EXTENDED
+};
+
+static int sock_over_op(
+	Operation *op,
+	SlapReply *rs
+)
+{
+	slap_overinst *on = (slap_overinst *)op->o_bd->bd_info;
+	void *private = op->o_bd->be_private;
+	slap_callback *sc;
+	struct sockinfo	*si;
+	slap_operation_t which;
+
+	switch (op->o_tag) {
+	case LDAP_REQ_BIND:	which = op_bind; break;
+	case LDAP_REQ_UNBIND:	which = op_unbind; break;
+	case LDAP_REQ_SEARCH:	which = op_search; break;
+	case LDAP_REQ_COMPARE:	which = op_compare; break;
+	case LDAP_REQ_MODIFY:	which = op_modify; break;
+	case LDAP_REQ_MODRDN:	which = op_modrdn; break;
+	case LDAP_REQ_ADD:	which = op_add; break;
+	case LDAP_REQ_DELETE:	which = op_delete; break;
+	case LDAP_REQ_EXTENDED:	which = op_extended; break;
+	default:
+		return SLAP_CB_CONTINUE;
+	}
+	si = on->on_bi.bi_private;
+	if ( !(si->si_ops & sockopflags[which]))
+		return SLAP_CB_CONTINUE;
+
+	if ( !BER_BVISEMPTY( &si->si_dnpatstr ) &&
+		regexec( &si->si_dnpat, op->o_req_ndn.bv_val, 0, NULL, 0 ))
+		return SLAP_CB_CONTINUE;
+
+	op->o_bd->be_private = si;
+	sc = op->o_callback;
+	op->o_callback = NULL;
+	sockfuncs[which]( op, rs );
+	op->o_bd->be_private = private;
+	op->o_callback = sc;
+	return rs->sr_err;
+}
+
+static int
+sock_over_response( Operation *op, SlapReply *rs )
+{
+	slap_overinst *on = (slap_overinst *)op->o_bd->bd_info;
+	struct sockinfo *si = (struct sockinfo *)on->on_bi.bi_private;
+	FILE *fp;
+
+	if ( rs->sr_type == REP_RESULT ) {
+		if ( !( si->si_resps & SOCK_REP_RESULT ))
+			return SLAP_CB_CONTINUE;
+	} else if ( rs->sr_type == REP_SEARCH ) {
+		if ( !( si->si_resps & SOCK_REP_SEARCH ))
+			return SLAP_CB_CONTINUE;
+	} else
+		return SLAP_CB_CONTINUE;
+
+	if (( fp = opensock( si->si_sockpath )) == NULL )
+		return SLAP_CB_CONTINUE;
+
+	if ( rs->sr_type == REP_RESULT ) {
+		/* write out the result */
+		fprintf( fp, "RESULT\n" );
+		fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+		sock_print_conn( fp, op->o_conn, si );
+		fprintf( fp, "code: %d\n", rs->sr_err );
+		if ( rs->sr_matched )
+			fprintf( fp, "matched: %s\n", rs->sr_matched );
+		if (rs->sr_text )
+			fprintf( fp, "info: %s\n", rs->sr_text );
+	} else {
+		/* write out the search entry */
+		int len;
+		fprintf( fp, "ENTRY\n" );
+		fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+		sock_print_conn( fp, op->o_conn, si );
+		ldap_pvt_thread_mutex_lock( &entry2str_mutex );
+		fprintf( fp, "%s", entry2str( rs->sr_entry, &len ) );
+		ldap_pvt_thread_mutex_unlock( &entry2str_mutex );
+	}
+	fprintf( fp, "\n" );
+	fclose( fp );
+
+	return SLAP_CB_CONTINUE;
+}
+
+static int
+sock_over_setup()
+{
+	int rc;
+
+	sockover.on_bi.bi_type = "sock";
+	sockover.on_bi.bi_db_init = sock_over_db_init;
+	sockover.on_bi.bi_db_destroy = sock_over_db_destroy;
+
+	sockover.on_bi.bi_op_bind = sock_over_op;
+	sockover.on_bi.bi_op_unbind = sock_over_op;
+	sockover.on_bi.bi_op_search = sock_over_op;
+	sockover.on_bi.bi_op_compare = sock_over_op;
+	sockover.on_bi.bi_op_modify = sock_over_op;
+	sockover.on_bi.bi_op_modrdn = sock_over_op;
+	sockover.on_bi.bi_op_add = sock_over_op;
+	sockover.on_bi.bi_op_delete = sock_over_op;
+	sockover.on_bi.bi_extended = sock_over_op;
+	sockover.on_response = sock_over_response;
+
+	sockover.on_bi.bi_cf_ocs = osocs;
+
+	rc = config_register_schema( bscfg, osocs );
+	if ( rc ) return rc;
+
+	return overlay_register( &sockover );
+}
+
+static int
+sock_over_db_init(
+    Backend	*be,
+	struct config_reply_s *cr
+)
+{
+	slap_overinst	*on = (slap_overinst *)be->bd_info;
+	void *private = be->be_private;
+	void *cf_ocs = be->be_cf_ocs;
+	int rc;
+
+	be->be_private = NULL;
+	rc = sock_back_db_init( be, cr );
+	on->on_bi.bi_private = be->be_private;
+	be->be_private = private;
+	be->be_cf_ocs = cf_ocs;
+	return rc;
+}
+
+static int
+sock_over_db_destroy(
+    Backend	*be,
+	struct config_reply_s *cr
+)
+{
+	slap_overinst	*on = (slap_overinst *)be->bd_info;
+	void *private = be->be_private;
+	int rc;
+
+	be->be_private = on->on_bi.bi_private;
+	rc = sock_back_db_destroy( be, cr );
+	on->on_bi.bi_private = be->be_private;
+	be->be_private = private;
+	return rc;
+}
diff --git a/servers/slapd/back-sock/delete.c b/servers/slapd/back-sock/delete.c
new file mode 100644
index 0000000..a657954
--- /dev/null
+++ b/servers/slapd/back-sock/delete.c
@@ -0,0 +1,75 @@
+/* delete.c - sock backend delete function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+int
+sock_back_delete(
+    Operation	*op,
+    SlapReply	*rs )
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	AttributeDescription *entry = slap_schema.si_ad_entry;
+	Entry e;
+	FILE			*fp;
+
+	e.e_id = NOID;
+	e.e_name = op->o_req_dn;
+	e.e_nname = op->o_req_ndn;
+	e.e_attrs = NULL;
+	e.e_ocflags = 0;
+	e.e_bv.bv_len = 0;
+	e.e_bv.bv_val = NULL;
+	e.e_private = NULL;
+
+	if ( ! access_allowed( op, &e,
+		entry, NULL, ACL_WDEL, NULL ) )
+	{
+		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
+		return -1;
+	}
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the delete process */
+	fprintf( fp, "DELETE\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "dn: %s\n", op->o_req_dn.bv_val );
+	fprintf( fp, "\n" );
+
+	/* read in the results and send them along */
+	sock_read_and_send_results( op, rs, fp );
+	fclose( fp );
+	return( 0 );
+}
diff --git a/servers/slapd/back-sock/extended.c b/servers/slapd/back-sock/extended.c
new file mode 100644
index 0000000..779c249
--- /dev/null
+++ b/servers/slapd/back-sock/extended.c
@@ -0,0 +1,76 @@
+/* extended.c - sock backend extended routines */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2000-2021 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>.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+#include <ac/string.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+#include "lutil.h"
+
+int
+sock_back_extended( Operation *op, SlapReply *rs )
+{
+	int			rc;
+	struct	sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	FILE		*fp;
+	struct berval b64;
+
+	Debug( LDAP_DEBUG_ARGS, "==> sock_back_extended(%s)\n",
+		op->ore_reqoid.bv_val, op->o_req_dn.bv_val, 0 );
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+			"could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the extended process */
+	fprintf( fp, "EXTENDED\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "oid: %s\n", op->ore_reqoid.bv_val );
+
+	if (op->ore_reqdata) {
+
+		b64.bv_len = LUTIL_BASE64_ENCODE_LEN( op->ore_reqdata->bv_len ) + 1;
+		b64.bv_val = op->o_tmpalloc( b64.bv_len + 1, op->o_tmpmemctx );
+
+		rc = lutil_b64_ntop(
+			(unsigned char *) op->ore_reqdata->bv_val, op->ore_reqdata->bv_len,
+			b64.bv_val, b64.bv_len );
+
+		b64.bv_len = rc;
+		assert( strlen(b64.bv_val) == b64.bv_len );
+
+		fprintf( fp, "value: %s\n", b64.bv_val );
+
+		op->o_tmpfree( b64.bv_val, op->o_tmpmemctx );
+
+	}
+
+	fprintf( fp, "\n" );
+
+	/* read in the results and send them along */
+	rc = sock_read_and_send_results( op, rs, fp );
+	fclose( fp );
+
+	return( rc );
+}
diff --git a/servers/slapd/back-sock/init.c b/servers/slapd/back-sock/init.c
new file mode 100644
index 0000000..ef15270
--- /dev/null
+++ b/servers/slapd/back-sock/init.c
@@ -0,0 +1,97 @@
+/* init.c - initialize sock backend */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/socket.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+int
+sock_back_initialize(
+    BackendInfo	*bi
+)
+{
+	bi->bi_open = 0;
+	bi->bi_config = 0;
+	bi->bi_close = 0;
+	bi->bi_destroy = 0;
+
+	bi->bi_db_init = sock_back_db_init;
+	bi->bi_db_config = 0;
+	bi->bi_db_open = 0;
+	bi->bi_db_close = 0;
+	bi->bi_db_destroy = sock_back_db_destroy;
+
+	bi->bi_op_bind = sock_back_bind;
+	bi->bi_op_unbind = sock_back_unbind;
+	bi->bi_op_search = sock_back_search;
+	bi->bi_op_compare = sock_back_compare;
+	bi->bi_op_modify = sock_back_modify;
+	bi->bi_op_modrdn = sock_back_modrdn;
+	bi->bi_op_add = sock_back_add;
+	bi->bi_op_delete = sock_back_delete;
+	bi->bi_op_abandon = 0;
+
+	bi->bi_extended = sock_back_extended;
+
+	bi->bi_chk_referrals = 0;
+
+	bi->bi_connection_init = 0;
+	bi->bi_connection_destroy = 0;
+
+	return sock_back_init_cf( bi );
+}
+
+int
+sock_back_db_init(
+    Backend	*be,
+	struct config_reply_s *cr
+)
+{
+	struct sockinfo	*si;
+
+	si = (struct sockinfo *) ch_calloc( 1, sizeof(struct sockinfo) );
+
+	be->be_private = si;
+	be->be_cf_ocs = be->bd_info->bi_cf_ocs;
+
+	return si == NULL;
+}
+
+int
+sock_back_db_destroy(
+    Backend	*be,
+	struct config_reply_s *cr
+)
+{
+	free( be->be_private );
+	return 0;
+}
+
+#if SLAPD_SOCK == SLAPD_MOD_DYNAMIC
+
+/* conditionally define the init_module() function */
+SLAP_BACKEND_INIT_MODULE( sock )
+
+#endif /* SLAPD_SOCK == SLAPD_MOD_DYNAMIC */
diff --git a/servers/slapd/back-sock/modify.c b/servers/slapd/back-sock/modify.c
new file mode 100644
index 0000000..dcf860d
--- /dev/null
+++ b/servers/slapd/back-sock/modify.c
@@ -0,0 +1,117 @@
+/* modify.c - sock backend modify function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+
+#include "slap.h"
+#include "back-sock.h"
+#include "ldif.h"
+
+int
+sock_back_modify(
+    Operation	*op,
+    SlapReply	*rs )
+{
+	Modification *mod;
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	AttributeDescription *entry = slap_schema.si_ad_entry;
+	Modifications *ml  = op->orm_modlist;
+	Entry e;
+	FILE			*fp;
+	int			i;
+
+	e.e_id = NOID;
+	e.e_name = op->o_req_dn;
+	e.e_nname = op->o_req_ndn;
+	e.e_attrs = NULL;
+	e.e_ocflags = 0;
+	e.e_bv.bv_len = 0;
+	e.e_bv.bv_val = NULL;
+	e.e_private = NULL;
+
+	if ( ! access_allowed( op, &e,
+		entry, NULL, ACL_WRITE, NULL ) )
+	{
+		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
+		return -1;
+	}
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the modify process */
+	fprintf( fp, "MODIFY\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "dn: %s\n", op->o_req_dn.bv_val );
+	for ( ; ml != NULL; ml = ml->sml_next ) {
+		mod = &ml->sml_mod;
+
+		switch ( mod->sm_op ) {
+		case LDAP_MOD_ADD:
+			fprintf( fp, "add: %s\n", mod->sm_desc->ad_cname.bv_val );
+			break;
+
+		case LDAP_MOD_DELETE:
+			fprintf( fp, "delete: %s\n", mod->sm_desc->ad_cname.bv_val );
+			break;
+
+		case LDAP_MOD_REPLACE:
+			fprintf( fp, "replace: %s\n", mod->sm_desc->ad_cname.bv_val );
+			break;
+
+		case LDAP_MOD_INCREMENT:
+			fprintf( fp, "increment: %s\n", mod->sm_desc->ad_cname.bv_val );
+			break;
+		}
+
+		if( mod->sm_values != NULL ) {
+			for ( i = 0; mod->sm_values[i].bv_val != NULL; i++ ) {
+				char *text = ldif_put_wrap( LDIF_PUT_VALUE,
+					mod->sm_desc->ad_cname.bv_val,
+					mod->sm_values[i].bv_val,
+					mod->sm_values[i].bv_len, LDIF_LINE_WIDTH_MAX );
+				if ( text ) {
+					fprintf( fp, "%s", text );
+					ber_memfree( text );
+				} else {
+					break;
+				}
+			}
+		}
+
+		fprintf( fp, "-\n" );
+	}
+	fprintf( fp, "\n" );
+
+	/* read in the results and send them along */
+	sock_read_and_send_results( op, rs, fp );
+	fclose( fp );
+	return( 0 );
+}
diff --git a/servers/slapd/back-sock/modrdn.c b/servers/slapd/back-sock/modrdn.c
new file mode 100644
index 0000000..7f1b7ca
--- /dev/null
+++ b/servers/slapd/back-sock/modrdn.c
@@ -0,0 +1,81 @@
+/* modrdn.c - sock backend modrdn function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/socket.h>
+#include <ac/string.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+int
+sock_back_modrdn(
+    Operation	*op,
+    SlapReply	*rs )
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	AttributeDescription *entry = slap_schema.si_ad_entry;
+	Entry e;
+	FILE			*fp;
+
+	e.e_id = NOID;
+	e.e_name = op->o_req_dn;
+	e.e_nname = op->o_req_ndn;
+	e.e_attrs = NULL;
+	e.e_ocflags = 0;
+	e.e_bv.bv_len = 0;
+	e.e_bv.bv_val = NULL;
+	e.e_private = NULL;
+
+	if ( ! access_allowed( op, &e, entry, NULL,
+			op->oq_modrdn.rs_newSup ? ACL_WDEL : ACL_WRITE,
+			NULL ) )
+	{
+		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
+		return -1;
+	}
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the modrdn process */
+	fprintf( fp, "MODRDN\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "dn: %s\n", op->o_req_dn.bv_val );
+	fprintf( fp, "newrdn: %s\n", op->oq_modrdn.rs_newrdn.bv_val );
+	fprintf( fp, "deleteoldrdn: %d\n", op->oq_modrdn.rs_deleteoldrdn ? 1 : 0 );
+	if ( op->oq_modrdn.rs_newSup != NULL ) {
+		fprintf( fp, "newSuperior: %s\n", op->oq_modrdn.rs_newSup->bv_val );
+	}
+	fprintf( fp, "\n" );
+
+	/* read in the results and send them along */
+	sock_read_and_send_results( op, rs, fp );
+	fclose( fp );
+	return( 0 );
+}
diff --git a/servers/slapd/back-sock/opensock.c b/servers/slapd/back-sock/opensock.c
new file mode 100644
index 0000000..cc93b1e
--- /dev/null
+++ b/servers/slapd/back-sock/opensock.c
@@ -0,0 +1,71 @@
+/* opensock.c - open a unix domain socket */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/errno.h>
+#include <ac/string.h>
+#include <ac/socket.h>
+#include <ac/unistd.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+/*
+ * FIXME: count the number of concurrent open sockets (since each thread
+ * may open one). Perhaps block here if a soft limit is reached, and fail
+ * if a hard limit reached
+ */
+
+FILE *
+opensock(
+    const char	*sockpath
+)
+{
+	int	fd;
+	FILE	*fp;
+	struct sockaddr_un sockun;
+
+	fd = socket(PF_UNIX, SOCK_STREAM, 0);
+	if ( fd < 0 ) {
+		Debug( LDAP_DEBUG_ANY, "socket create failed\n", 0, 0, 0 );
+		return( NULL );
+	}
+
+	sockun.sun_family = AF_UNIX;
+	sprintf(sockun.sun_path, "%.*s", (int)(sizeof(sockun.sun_path)-1),
+		sockpath);
+	if ( connect( fd, (struct sockaddr *)&sockun, sizeof(sockun) ) < 0 ) {
+		Debug( LDAP_DEBUG_ANY, "socket connect(%s) failed\n",
+			sockpath ? sockpath : "<null>", 0, 0 );
+		close( fd );
+		return( NULL );
+	}
+
+	if ( ( fp = fdopen( fd, "r+" ) ) == NULL ) {
+		Debug( LDAP_DEBUG_ANY, "fdopen failed\n", 0, 0, 0 );
+		close( fd );
+		return( NULL );
+	}
+
+	return( fp );
+}
diff --git a/servers/slapd/back-sock/proto-sock.h b/servers/slapd/back-sock/proto-sock.h
new file mode 100644
index 0000000..76410a7
--- /dev/null
+++ b/servers/slapd/back-sock/proto-sock.h
@@ -0,0 +1,49 @@
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#ifndef _PROTO_SOCK_H
+#define _PROTO_SOCK_H
+
+LDAP_BEGIN_DECL
+
+extern BI_init		sock_back_initialize;
+
+extern BI_open		sock_back_open;
+extern BI_close		sock_back_close;
+extern BI_destroy	sock_back_destroy;
+
+extern BI_db_init	sock_back_db_init;
+extern BI_db_destroy	sock_back_db_destroy;
+
+extern BI_op_bind	sock_back_bind;
+extern BI_op_unbind	sock_back_unbind;
+extern BI_op_search	sock_back_search;
+extern BI_op_compare	sock_back_compare;
+extern BI_op_modify	sock_back_modify;
+extern BI_op_modrdn	sock_back_modrdn;
+extern BI_op_add	sock_back_add;
+extern BI_op_delete	sock_back_delete;
+
+extern BI_op_extended	sock_back_extended;
+
+extern int sock_back_init_cf( BackendInfo *bi );
+
+LDAP_END_DECL
+
+#endif /* _PROTO_SOCK_H */
diff --git a/servers/slapd/back-sock/result.c b/servers/slapd/back-sock/result.c
new file mode 100644
index 0000000..f4c93d1
--- /dev/null
+++ b/servers/slapd/back-sock/result.c
@@ -0,0 +1,167 @@
+/* result.c - sock backend result reading function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/errno.h>
+#include <ac/string.h>
+#include <ac/socket.h>
+#include <ac/unistd.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+/*
+ * FIXME: make a RESULT section compulsory from the socket response.
+ * Otherwise, a partial/aborted response is treated as 'success'.
+ * This is a divergence from the back-shell protocol, but makes things
+ * more robust.
+ */
+
+int
+sock_read_and_send_results(
+    Operation	*op,
+    SlapReply	*rs,
+    FILE	*fp )
+{
+	int	bsize, len;
+	char	*buf, *bp;
+	char	line[BUFSIZ];
+	char	ebuf[128];
+
+	(void) fflush(fp);
+	/* read in the result and send it along */
+	buf = (char *) ch_malloc( BUFSIZ );
+	buf[0] = '\0';
+	bsize = BUFSIZ;
+	bp = buf;
+	while ( !feof(fp) ) {
+		errno = 0;
+		if ( fgets( line, sizeof(line), fp ) == NULL ) {
+			if ( errno == EINTR ) continue;
+
+			Debug( LDAP_DEBUG_ANY, "sock: fgets failed: %s (%d)\n",
+				AC_STRERROR_R(errno, ebuf, sizeof ebuf), errno, 0 ); 
+			break;
+		}
+
+		Debug( LDAP_DEBUG_SHELL, "sock search reading line (%s)\n",
+		    line, 0, 0 );
+
+		/* ignore lines beginning with # (LDIFv1 comments) */
+		if ( *line == '#' ) {
+			continue;
+		}
+
+		/* ignore lines beginning with DEBUG: */
+		if ( strncasecmp( line, "DEBUG:", 6 ) == 0 ) {
+			continue;
+		}
+
+		if ( strncasecmp( line, "CONTINUE", 8 ) == 0 ) {
+			struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+			/* Only valid when operating as an overlay! */
+			assert( si->si_ops != 0 );
+			rs->sr_err = SLAP_CB_CONTINUE;
+			goto skip;
+		}
+
+		len = strlen( line );
+		while ( bp + len + 1 - buf > bsize ) {
+			size_t offset = bp - buf;
+			bsize += BUFSIZ;
+			buf = (char *) ch_realloc( buf, bsize );
+			bp = &buf[offset];
+		}
+		strcpy( bp, line );
+		bp += len;
+
+		/* line marked the end of an entry or result */
+		if ( *line == '\n' ) {
+			if ( strncasecmp( buf, "RESULT", 6 ) == 0 ) {
+				break;
+			}
+
+			if ( (rs->sr_entry = str2entry( buf )) == NULL ) {
+				Debug( LDAP_DEBUG_ANY, "str2entry(%s) failed\n",
+				    buf, 0, 0 );
+			} else {
+				rs->sr_attrs = op->oq_search.rs_attrs;
+				rs->sr_flags = REP_ENTRY_MODIFIABLE;
+				send_search_entry( op, rs );
+				entry_free( rs->sr_entry );
+				rs->sr_attrs = NULL;
+			}
+
+			bp = buf;
+		}
+	}
+	(void) str2result( buf, &rs->sr_err, (char **)&rs->sr_matched, (char **)&rs->sr_text );
+
+	/* otherwise, front end will send this result */
+	if ( rs->sr_err != 0 || op->o_tag != LDAP_REQ_BIND ) {
+		send_ldap_result( op, rs );
+	}
+
+skip:
+	ch_free( buf );
+
+	return( rs->sr_err );
+}
+
+void
+sock_print_suffixes(
+    FILE	*fp,
+    Backend	*be
+)
+{
+	int	i;
+
+	for ( i = 0; be->be_suffix[i].bv_val != NULL; i++ ) {
+		fprintf( fp, "suffix: %s\n", be->be_suffix[i].bv_val );
+	}
+}
+
+void
+sock_print_conn(
+    FILE	*fp,
+    Connection	*conn,
+    struct sockinfo *si
+)
+{
+	if ( conn == NULL ) return;
+
+	if( si->si_extensions & SOCK_EXT_BINDDN ) {
+		fprintf( fp, "binddn: %s\n",
+			conn->c_dn.bv_len ? conn->c_dn.bv_val : "" );
+	}
+	if( si->si_extensions & SOCK_EXT_PEERNAME ) {
+		fprintf( fp, "peername: %s\n",
+			conn->c_peer_name.bv_len ? conn->c_peer_name.bv_val : "" );
+	}
+	if( si->si_extensions & SOCK_EXT_SSF ) {
+		fprintf( fp, "ssf: %d\n", conn->c_ssf );
+	}
+	if( si->si_extensions & SOCK_EXT_CONNID ) {
+		fprintf( fp, "connid: %lu\n", conn->c_connid );
+	}
+}
diff --git a/servers/slapd/back-sock/search.c b/servers/slapd/back-sock/search.c
new file mode 100644
index 0000000..2a8279b
--- /dev/null
+++ b/servers/slapd/back-sock/search.c
@@ -0,0 +1,74 @@
+/* search.c - sock backend search function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/socket.h>
+#include <ac/string.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+/*
+ * FIXME: add a filterSearchResults option like back-perl has
+ */
+
+int
+sock_back_search(
+    Operation	*op,
+    SlapReply	*rs )
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	FILE			*fp;
+	AttributeName		*an;
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the search process */
+	fprintf( fp, "SEARCH\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "base: %s\n", op->o_req_dn.bv_val );
+	fprintf( fp, "scope: %d\n", op->oq_search.rs_scope );
+	fprintf( fp, "deref: %d\n", op->oq_search.rs_deref );
+	fprintf( fp, "sizelimit: %d\n", op->oq_search.rs_slimit );
+	fprintf( fp, "timelimit: %d\n", op->oq_search.rs_tlimit );
+	fprintf( fp, "filter: %s\n", op->oq_search.rs_filterstr.bv_val );
+	fprintf( fp, "attrsonly: %d\n", op->oq_search.rs_attrsonly ? 1 : 0 );
+	fprintf( fp, "attrs:%s", op->oq_search.rs_attrs == NULL ? " all" : "" );
+	for ( an = op->oq_search.rs_attrs; an && an->an_name.bv_val; an++ ) {
+		fprintf( fp, " %s", an->an_name.bv_val );
+	}
+	fprintf( fp, "\n\n" );  /* end of attr line plus blank line */
+
+	/* read in the results and send them along */
+	rs->sr_attrs = op->oq_search.rs_attrs;
+	sock_read_and_send_results( op, rs, fp );
+
+	fclose( fp );
+	return( 0 );
+}
diff --git a/servers/slapd/back-sock/searchexample.conf b/servers/slapd/back-sock/searchexample.conf
new file mode 100644
index 0000000..ac88c68
--- /dev/null
+++ b/servers/slapd/back-sock/searchexample.conf
@@ -0,0 +1,23 @@
+# $OpenLDAP$
+## This work is part of OpenLDAP Software <http://www.openldap.org/>.
+##
+## Copyright 2007-2021 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 Brian Candler for inclusion
+## in OpenLDAP Software.
+
+include		/usr/local/etc/openldap/schema/core.schema
+
+database	sock
+suffix		"dc=example,dc=com"
+socketpath	/tmp/example.sock
diff --git a/servers/slapd/back-sock/searchexample.pl b/servers/slapd/back-sock/searchexample.pl
new file mode 100644
index 0000000..a9b066c
--- /dev/null
+++ b/servers/slapd/back-sock/searchexample.pl
@@ -0,0 +1,90 @@
+#!/usr/bin/perl -w -T
+# $OpenLDAP$
+## This work is part of OpenLDAP Software <http://www.openldap.org/>.
+##
+## Copyright 2007-2021 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 Brian Candler for inclusion
+## in OpenLDAP Software.
+
+# See: http://search.cpan.org/dist/Net-Server/
+
+package ExampleDB;
+
+use strict;
+use vars qw(@ISA);
+use Net::Server::PreFork; # any personality will do
+
+@ISA = qw(Net::Server::PreFork);
+
+ExampleDB->run(
+  port=>"/tmp/example.sock|unix"
+  #conf_file=>"/etc/example.conf"
+);
+exit;
+
+### over-ridden subs below
+# The protocol is the same as back-shell
+
+sub process_request {
+  my $self = shift;
+
+  eval {
+
+    local $SIG{ALRM} = sub { die "Timed Out!\n" };
+    my $timeout = 30; # give the user 30 seconds to type a line
+    alarm($timeout);
+
+    my $request = <STDIN>;
+    
+    if ($request eq "SEARCH\n") {
+      my %req = ();
+      while (my $line = <STDIN>) {
+        chomp($line);
+        last if $line eq "";
+        if ($line =~ /^([^:]+):\s*(.*)$/) { # FIXME: handle base64 encoded
+          $req{$1} = $2;
+        }
+      }
+      #sleep(2);  # to test concurrency
+      print "dn: cn=test, dc=example, dc=com\n";
+      print "cn: test\n";
+      print "objectclass: cnobject\n";
+      print "\n";
+      print "RESULT\n";
+      print "code: 0\n";
+      print "info: answered by process $$\n";      
+    }
+    else {
+      print "RESULT\n";
+      print "code: 53\n";  # unwillingToPerform
+      print "info: I don't implement $request";
+    }
+
+  };
+
+  return unless $@;
+  if( $@=~/timed out/i ){
+    print "RESULT\n";
+    print "code: 3\n"; # timeLimitExceeded
+    print "info: Timed out\n";
+  }
+  else {
+    print "RESULT\n";
+    print "code: 1\n"; # operationsError
+    print "info: $@\n"; # FIXME: remove CR/LF
+  }
+
+}
+
+1;
diff --git a/servers/slapd/back-sock/unbind.c b/servers/slapd/back-sock/unbind.c
new file mode 100644
index 0000000..5af29fc
--- /dev/null
+++ b/servers/slapd/back-sock/unbind.c
@@ -0,0 +1,57 @@
+/* unbind.c - sock backend unbind function */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2007-2021 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 Brian Candler for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/socket.h>
+#include <ac/string.h>
+
+#include "slap.h"
+#include "back-sock.h"
+
+int
+sock_back_unbind(
+    Operation		*op,
+    SlapReply		*rs
+)
+{
+	struct sockinfo	*si = (struct sockinfo *) op->o_bd->be_private;
+	FILE			*fp;
+
+	if ( (fp = opensock( si->si_sockpath )) == NULL ) {
+		send_ldap_error( op, rs, LDAP_OTHER,
+		    "could not open socket" );
+		return( -1 );
+	}
+
+	/* write out the request to the unbind process */
+	fprintf( fp, "UNBIND\n" );
+	fprintf( fp, "msgid: %ld\n", (long) op->o_msgid );
+	sock_print_conn( fp, op->o_conn, si );
+	sock_print_suffixes( fp, op->o_bd );
+	fprintf( fp, "\n" );
+
+	/* no response to unbind */
+	fclose( fp );
+
+	return 0;
+}