Initial commitstart

1 files changed, 1459 insertions, 0 deletions

diff --git a/bin/named/controlconf.c b/bin/named/controlconf.c
new file mode 100644
index 0000000..766f013
--- /dev/null
+++ b/bin/named/controlconf.c
@@ -0,0 +1,1459 @@
+/*
+ * Copyright (C) 2004-2008  Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 2001-2003  Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: controlconf.c,v 1.60 2008/07/23 23:27:54 marka Exp $ */
+
+/*! \file */
+
+#include <config.h>
+
+#include <isc/base64.h>
+#include <isc/buffer.h>
+#include <isc/event.h>
+#include <isc/mem.h>
+#include <isc/net.h>
+#include <isc/netaddr.h>
+#include <isc/random.h>
+#include <isc/result.h>
+#include <isc/stdtime.h>
+#include <isc/string.h>
+#include <isc/timer.h>
+#include <isc/util.h>
+
+#include <isccfg/namedconf.h>
+
+#include <bind9/check.h>
+
+#include <isccc/alist.h>
+#include <isccc/cc.h>
+#include <isccc/ccmsg.h>
+#include <isccc/events.h>
+#include <isccc/result.h>
+#include <isccc/sexpr.h>
+#include <isccc/symtab.h>
+#include <isccc/util.h>
+
+#include <dns/result.h>
+
+#include <named/config.h>
+#include <named/control.h>
+#include <named/log.h>
+#include <named/server.h>
+
+/*
+ * Note: Listeners and connections are not locked.  All event handlers are
+ * executed by the server task, and all callers of exported routines must
+ * be running under the server task.
+ */
+
+typedef struct controlkey controlkey_t;
+typedef ISC_LIST(controlkey_t) controlkeylist_t;
+
+typedef struct controlconnection controlconnection_t;
+typedef ISC_LIST(controlconnection_t) controlconnectionlist_t;
+
+typedef struct controllistener controllistener_t;
+typedef ISC_LIST(controllistener_t) controllistenerlist_t;
+
+struct controlkey {
+	char *				keyname;
+	isc_region_t			secret;
+	ISC_LINK(controlkey_t)		link;
+};
+
+struct controlconnection {
+	isc_socket_t *			sock;
+	isccc_ccmsg_t			ccmsg;
+	isc_boolean_t			ccmsg_valid;
+	isc_boolean_t			sending;
+	isc_timer_t *			timer;
+	unsigned char			buffer[2048];
+	controllistener_t *		listener;
+	isc_uint32_t			nonce;
+	ISC_LINK(controlconnection_t)	link;
+};
+
+struct controllistener {
+	ns_controls_t *			controls;
+	isc_mem_t *			mctx;
+	isc_task_t *			task;
+	isc_sockaddr_t			address;
+	isc_socket_t *			sock;
+	dns_acl_t *			acl;
+	isc_boolean_t			listening;
+	isc_boolean_t			exiting;
+	controlkeylist_t		keys;
+	controlconnectionlist_t		connections;
+	isc_sockettype_t		type;
+	isc_uint32_t			perm;
+	isc_uint32_t			owner;
+	isc_uint32_t			group;
+	ISC_LINK(controllistener_t)	link;
+};
+
+struct ns_controls {
+	ns_server_t			*server;
+	controllistenerlist_t 		listeners;
+	isc_boolean_t			shuttingdown;
+	isccc_symtab_t			*symtab;
+};
+
+static void control_newconn(isc_task_t *task, isc_event_t *event);
+static void control_recvmessage(isc_task_t *task, isc_event_t *event);
+
+#define CLOCKSKEW 300
+
+static void
+free_controlkey(controlkey_t *key, isc_mem_t *mctx) {
+	if (key->keyname != NULL)
+		isc_mem_free(mctx, key->keyname);
+	if (key->secret.base != NULL)
+		isc_mem_put(mctx, key->secret.base, key->secret.length);
+	isc_mem_put(mctx, key, sizeof(*key));
+}
+
+static void
+free_controlkeylist(controlkeylist_t *keylist, isc_mem_t *mctx) {
+	while (!ISC_LIST_EMPTY(*keylist)) {
+		controlkey_t *key = ISC_LIST_HEAD(*keylist);
+		ISC_LIST_UNLINK(*keylist, key, link);
+		free_controlkey(key, mctx);
+	}
+}
+
+static void
+free_listener(controllistener_t *listener) {
+	INSIST(listener->exiting);
+	INSIST(!listener->listening);
+	INSIST(ISC_LIST_EMPTY(listener->connections));
+
+	if (listener->sock != NULL)
+		isc_socket_detach(&listener->sock);
+
+	free_controlkeylist(&listener->keys, listener->mctx);
+
+	if (listener->acl != NULL)
+		dns_acl_detach(&listener->acl);
+
+	isc_mem_put(listener->mctx, listener, sizeof(*listener));
+}
+
+static void
+maybe_free_listener(controllistener_t *listener) {
+	if (listener->exiting &&
+	    !listener->listening &&
+	    ISC_LIST_EMPTY(listener->connections))
+		free_listener(listener);
+}
+
+static void
+maybe_free_connection(controlconnection_t *conn) {
+	controllistener_t *listener = conn->listener;
+
+	if (conn->timer != NULL)
+		isc_timer_detach(&conn->timer);
+
+	if (conn->ccmsg_valid) {
+		isccc_ccmsg_cancelread(&conn->ccmsg);
+		return;
+	}
+
+	if (conn->sending) {
+		isc_socket_cancel(conn->sock, listener->task,
+				  ISC_SOCKCANCEL_SEND);
+		return;
+	}
+
+	ISC_LIST_UNLINK(listener->connections, conn, link);
+	isc_mem_put(listener->mctx, conn, sizeof(*conn));
+}
+
+static void
+shutdown_listener(controllistener_t *listener) {
+	controlconnection_t *conn;
+	controlconnection_t *next;
+
+	if (!listener->exiting) {
+		char socktext[ISC_SOCKADDR_FORMATSIZE];
+
+		ISC_LIST_UNLINK(listener->controls->listeners, listener, link);
+
+		isc_sockaddr_format(&listener->address, socktext,
+				    sizeof(socktext));
+		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+			      NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE,
+			      "stopping command channel on %s", socktext);
+		if (listener->type == isc_sockettype_unix)
+			isc_socket_cleanunix(&listener->address, ISC_TRUE);
+		listener->exiting = ISC_TRUE;
+	}
+
+	for (conn = ISC_LIST_HEAD(listener->connections);
+	     conn != NULL;
+	     conn = next)
+	{
+		next = ISC_LIST_NEXT(conn, link);
+		maybe_free_connection(conn);
+	}
+
+	if (listener->listening)
+		isc_socket_cancel(listener->sock, listener->task,
+				  ISC_SOCKCANCEL_ACCEPT);
+
+	maybe_free_listener(listener);
+}
+
+static isc_boolean_t
+address_ok(isc_sockaddr_t *sockaddr, dns_acl_t *acl) {
+	isc_netaddr_t netaddr;
+	isc_result_t result;
+	int match;
+
+	isc_netaddr_fromsockaddr(&netaddr, sockaddr);
+
+	result = dns_acl_match(&netaddr, NULL, acl,
+			       &ns_g_server->aclenv, &match, NULL);
+
+	if (result != ISC_R_SUCCESS || match <= 0)
+		return (ISC_FALSE);
+	else
+		return (ISC_TRUE);
+}
+
+static isc_result_t
+control_accept(controllistener_t *listener) {
+	isc_result_t result;
+	result = isc_socket_accept(listener->sock,
+				   listener->task,
+				   control_newconn, listener);
+	if (result != ISC_R_SUCCESS)
+		UNEXPECTED_ERROR(__FILE__, __LINE__,
+				 "isc_socket_accept() failed: %s",
+				 isc_result_totext(result));
+	else
+		listener->listening = ISC_TRUE;
+	return (result);
+}
+
+static isc_result_t
+control_listen(controllistener_t *listener) {
+	isc_result_t result;
+
+	result = isc_socket_listen(listener->sock, 0);
+	if (result != ISC_R_SUCCESS)
+		UNEXPECTED_ERROR(__FILE__, __LINE__,
+				 "isc_socket_listen() failed: %s",
+				 isc_result_totext(result));
+	return (result);
+}
+
+static void
+control_next(controllistener_t *listener) {
+	(void)control_accept(listener);
+}
+
+static void
+control_senddone(isc_task_t *task, isc_event_t *event) {
+	isc_socketevent_t *sevent = (isc_socketevent_t *) event;
+	controlconnection_t *conn = event->ev_arg;
+	controllistener_t *listener = conn->listener;
+	isc_socket_t *sock = (isc_socket_t *)sevent->ev_sender;
+	isc_result_t result;
+
+	REQUIRE(conn->sending);
+
+	UNUSED(task);
+
+	conn->sending = ISC_FALSE;
+
+	if (sevent->result != ISC_R_SUCCESS &&
+	    sevent->result != ISC_R_CANCELED)
+	{
+		char socktext[ISC_SOCKADDR_FORMATSIZE];
+		isc_sockaddr_t peeraddr;
+
+		(void)isc_socket_getpeername(sock, &peeraddr);
+		isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
+		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
+			      "error sending command response to %s: %s",
+			      socktext, isc_result_totext(sevent->result));
+	}
+	isc_event_free(&event);
+
+	result = isccc_ccmsg_readmessage(&conn->ccmsg, listener->task,
+					 control_recvmessage, conn);
+	if (result != ISC_R_SUCCESS) {
+		isc_socket_detach(&conn->sock);
+		maybe_free_connection(conn);
+		maybe_free_listener(listener);
+	}
+}
+
+static inline void
+log_invalid(isccc_ccmsg_t *ccmsg, isc_result_t result) {
+	char socktext[ISC_SOCKADDR_FORMATSIZE];
+	isc_sockaddr_t peeraddr;
+
+	(void)isc_socket_getpeername(ccmsg->sock, &peeraddr);
+	isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
+	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+		      NS_LOGMODULE_CONTROL, ISC_LOG_ERROR,
+		      "invalid command from %s: %s",
+		      socktext, isc_result_totext(result));
+}
+
+static void
+control_recvmessage(isc_task_t *task, isc_event_t *event) {
+	controlconnection_t *conn;
+	controllistener_t *listener;
+	controlkey_t *key;
+	isccc_sexpr_t *request = NULL;
+	isccc_sexpr_t *response = NULL;
+	isccc_region_t ccregion;
+	isccc_region_t secret;
+	isc_stdtime_t now;
+	isc_buffer_t b;
+	isc_region_t r;
+	isc_uint32_t len;
+	isc_buffer_t text;
+	char textarray[1024];
+	isc_result_t result;
+	isc_result_t eresult;
+	isccc_sexpr_t *_ctrl;
+	isccc_time_t sent;
+	isccc_time_t exp;
+	isc_uint32_t nonce;
+
+	REQUIRE(event->ev_type == ISCCC_EVENT_CCMSG);
+
+	conn = event->ev_arg;
+	listener = conn->listener;
+	secret.rstart = NULL;
+
+	/* Is the server shutting down? */
+	if (listener->controls->shuttingdown)
+		goto cleanup;
+
+	if (conn->ccmsg.result != ISC_R_SUCCESS) {
+		if (conn->ccmsg.result != ISC_R_CANCELED &&
+		    conn->ccmsg.result != ISC_R_EOF)
+			log_invalid(&conn->ccmsg, conn->ccmsg.result);
+		goto cleanup;
+	}
+
+	request = NULL;
+
+	for (key = ISC_LIST_HEAD(listener->keys);
+	     key != NULL;
+	     key = ISC_LIST_NEXT(key, link))
+	{
+		ccregion.rstart = isc_buffer_base(&conn->ccmsg.buffer);
+		ccregion.rend = isc_buffer_used(&conn->ccmsg.buffer);
+		secret.rstart = isc_mem_get(listener->mctx, key->secret.length);
+		if (secret.rstart == NULL)
+			goto cleanup;
+		memcpy(secret.rstart, key->secret.base, key->secret.length);
+		secret.rend = secret.rstart + key->secret.length;
+		result = isccc_cc_fromwire(&ccregion, &request, &secret);
+		if (result == ISC_R_SUCCESS)
+			break;
+		isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret));
+		if (result == ISCCC_R_BADAUTH) {
+			/*
+			 * For some reason, request is non-NULL when
+			 * isccc_cc_fromwire returns ISCCC_R_BADAUTH.
+			 */
+			if (request != NULL)
+				isccc_sexpr_free(&request);
+		} else {
+			log_invalid(&conn->ccmsg, result);
+			goto cleanup;
+		}
+	}
+
+	if (key == NULL) {
+		log_invalid(&conn->ccmsg, ISCCC_R_BADAUTH);
+		goto cleanup;
+	}
+
+	/* We shouldn't be getting a reply. */
+	if (isccc_cc_isreply(request)) {
+		log_invalid(&conn->ccmsg, ISC_R_FAILURE);
+		goto cleanup_request;
+	}
+
+	isc_stdtime_get(&now);
+
+	/*
+	 * Limit exposure to replay attacks.
+	 */
+	_ctrl = isccc_alist_lookup(request, "_ctrl");
+	if (_ctrl == NULL) {
+		log_invalid(&conn->ccmsg, ISC_R_FAILURE);
+		goto cleanup_request;
+	}
+
+	if (isccc_cc_lookupuint32(_ctrl, "_tim", &sent) == ISC_R_SUCCESS) {
+		if ((sent + CLOCKSKEW) < now || (sent - CLOCKSKEW) > now) {
+			log_invalid(&conn->ccmsg, ISCCC_R_CLOCKSKEW);
+			goto cleanup_request;
+		}
+	} else {
+		log_invalid(&conn->ccmsg, ISC_R_FAILURE);
+		goto cleanup_request;
+	}
+
+	/*
+	 * Expire messages that are too old.
+	 */
+	if (isccc_cc_lookupuint32(_ctrl, "_exp", &exp) == ISC_R_SUCCESS &&
+	    now > exp) {
+		log_invalid(&conn->ccmsg, ISCCC_R_EXPIRED);
+		goto cleanup_request;
+	}
+
+	/*
+	 * Duplicate suppression (required for UDP).
+	 */
+	isccc_cc_cleansymtab(listener->controls->symtab, now);
+	result = isccc_cc_checkdup(listener->controls->symtab, request, now);
+	if (result != ISC_R_SUCCESS) {
+		if (result == ISC_R_EXISTS)
+			result = ISCCC_R_DUPLICATE;
+		log_invalid(&conn->ccmsg, result);
+		goto cleanup_request;
+	}
+
+	if (conn->nonce != 0 &&
+	    (isccc_cc_lookupuint32(_ctrl, "_nonce", &nonce) != ISC_R_SUCCESS ||
+	     conn->nonce != nonce)) {
+		log_invalid(&conn->ccmsg, ISCCC_R_BADAUTH);
+		goto cleanup_request;
+	}
+
+	/*
+	 * Establish nonce.
+	 */
+	while (conn->nonce == 0)
+		isc_random_get(&conn->nonce);
+
+	isc_buffer_init(&text, textarray, sizeof(textarray));
+	eresult = ns_control_docommand(request, &text);
+
+	result = isccc_cc_createresponse(request, now, now + 60, &response);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup_request;
+	if (eresult != ISC_R_SUCCESS) {
+		isccc_sexpr_t *data;
+
+		data = isccc_alist_lookup(response, "_data");
+		if (data != NULL) {
+			const char *estr = isc_result_totext(eresult);
+			if (isccc_cc_definestring(data, "err", estr) == NULL)
+				goto cleanup_response;
+		}
+	}
+
+	if (isc_buffer_usedlength(&text) > 0) {
+		isccc_sexpr_t *data;
+
+		data = isccc_alist_lookup(response, "_data");
+		if (data != NULL) {
+			char *str = (char *)isc_buffer_base(&text);
+			if (isccc_cc_definestring(data, "text", str) == NULL)
+				goto cleanup_response;
+		}
+	}
+
+	_ctrl = isccc_alist_lookup(response, "_ctrl");
+	if (_ctrl == NULL ||
+	    isccc_cc_defineuint32(_ctrl, "_nonce", conn->nonce) == NULL)
+		goto cleanup_response;
+
+	ccregion.rstart = conn->buffer + 4;
+	ccregion.rend = conn->buffer + sizeof(conn->buffer);
+	result = isccc_cc_towire(response, &ccregion, &secret);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup_response;
+	isc_buffer_init(&b, conn->buffer, 4);
+	len = sizeof(conn->buffer) - REGION_SIZE(ccregion);
+	isc_buffer_putuint32(&b, len - 4);
+	r.base = conn->buffer;
+	r.length = len;
+
+	result = isc_socket_send(conn->sock, &r, task, control_senddone, conn);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup_response;
+	conn->sending = ISC_TRUE;
+
+	isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret));
+	isccc_sexpr_free(&request);
+	isccc_sexpr_free(&response);
+	return;
+
+ cleanup_response:
+	isccc_sexpr_free(&response);
+
+ cleanup_request:
+	isccc_sexpr_free(&request);
+	isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret));
+
+ cleanup:
+	isc_socket_detach(&conn->sock);
+	isccc_ccmsg_invalidate(&conn->ccmsg);
+	conn->ccmsg_valid = ISC_FALSE;
+	maybe_free_connection(conn);
+	maybe_free_listener(listener);
+}
+
+static void
+control_timeout(isc_task_t *task, isc_event_t *event) {
+	controlconnection_t *conn = event->ev_arg;
+
+	UNUSED(task);
+
+	isc_timer_detach(&conn->timer);
+	maybe_free_connection(conn);
+
+	isc_event_free(&event);
+}
+
+static isc_result_t
+newconnection(controllistener_t *listener, isc_socket_t *sock) {
+	controlconnection_t *conn;
+	isc_interval_t interval;
+	isc_result_t result;
+
+	conn = isc_mem_get(listener->mctx, sizeof(*conn));
+	if (conn == NULL)
+		return (ISC_R_NOMEMORY);
+
+	conn->sock = sock;
+	isccc_ccmsg_init(listener->mctx, sock, &conn->ccmsg);
+	conn->ccmsg_valid = ISC_TRUE;
+	conn->sending = ISC_FALSE;
+	conn->timer = NULL;
+	isc_interval_set(&interval, 60, 0);
+	result = isc_timer_create(ns_g_timermgr, isc_timertype_once,
+				  NULL, &interval, listener->task,
+				  control_timeout, conn, &conn->timer);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup;
+
+	conn->listener = listener;
+	conn->nonce = 0;
+	ISC_LINK_INIT(conn, link);
+
+	result = isccc_ccmsg_readmessage(&conn->ccmsg, listener->task,
+					 control_recvmessage, conn);
+	if (result != ISC_R_SUCCESS)
+		goto cleanup;
+	isccc_ccmsg_setmaxsize(&conn->ccmsg, 2048);
+
+	ISC_LIST_APPEND(listener->connections, conn, link);
+	return (ISC_R_SUCCESS);
+
+ cleanup:
+	isccc_ccmsg_invalidate(&conn->ccmsg);
+	if (conn->timer != NULL)
+		isc_timer_detach(&conn->timer);
+	isc_mem_put(listener->mctx, conn, sizeof(*conn));
+	return (result);
+}
+
+static void
+control_newconn(isc_task_t *task, isc_event_t *event) {
+	isc_socket_newconnev_t *nevent = (isc_socket_newconnev_t *)event;
+	controllistener_t *listener = event->ev_arg;
+	isc_socket_t *sock;
+	isc_sockaddr_t peeraddr;
+	isc_result_t result;
+
+	UNUSED(task);
+
+	listener->listening = ISC_FALSE;
+
+	if (nevent->result != ISC_R_SUCCESS) {
+		if (nevent->result == ISC_R_CANCELED) {
+			shutdown_listener(listener);
+			goto cleanup;
+		}
+		goto restart;
+	}
+
+	sock = nevent->newsocket;
+	isc_socket_setname(sock, "control", NULL);
+	(void)isc_socket_getpeername(sock, &peeraddr);
+	if (listener->type == isc_sockettype_tcp &&
+	    !address_ok(&peeraddr, listener->acl)) {
+		char socktext[ISC_SOCKADDR_FORMATSIZE];
+		isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
+		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
+			      "rejected command channel message from %s",
+			      socktext);
+		isc_socket_detach(&sock);
+		goto restart;
+	}
+
+	result = newconnection(listener, sock);
+	if (result != ISC_R_SUCCESS) {
+		char socktext[ISC_SOCKADDR_FORMATSIZE];
+		isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
+		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
+			      "dropped command channel from %s: %s",
+			      socktext, isc_result_totext(result));
+		isc_socket_detach(&sock);
+		goto restart;
+	}
+
+ restart:
+	control_next(listener);
+ cleanup:
+	isc_event_free(&event);
+}
+
+static void
+controls_shutdown(ns_controls_t *controls) {
+	controllistener_t *listener;
+	controllistener_t *next;
+
+	for (listener = ISC_LIST_HEAD(controls->listeners);
+	     listener != NULL;
+	     listener = next)
+	{
+		/*
+		 * This is asynchronous.  As listeners shut down, they will
+		 * call their callbacks.
+		 */
+		next = ISC_LIST_NEXT(listener, link);
+		shutdown_listener(listener);
+	}
+}
+
+void
+ns_controls_shutdown(ns_controls_t *controls) {
+	controls_shutdown(controls);
+	controls->shuttingdown = ISC_TRUE;
+}
+
+static isc_result_t
+cfgkeylist_find(const cfg_obj_t *keylist, const char *keyname,
+		const cfg_obj_t **objp)
+{
+	const cfg_listelt_t *element;
+	const char *str;
+	const cfg_obj_t *obj;
+
+	for (element = cfg_list_first(keylist);
+	     element != NULL;
+	     element = cfg_list_next(element))
+	{
+		obj = cfg_listelt_value(element);
+		str = cfg_obj_asstring(cfg_map_getname(obj));
+		if (strcasecmp(str, keyname) == 0)
+			break;
+	}
+	if (element == NULL)
+		return (ISC_R_NOTFOUND);
+	obj = cfg_listelt_value(element);
+	*objp = obj;
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+controlkeylist_fromcfg(const cfg_obj_t *keylist, isc_mem_t *mctx,
+		       controlkeylist_t *keyids)
+{
+	const cfg_listelt_t *element;
+	char *newstr = NULL;
+	const char *str;
+	const cfg_obj_t *obj;
+	controlkey_t *key;
+
+	for (element = cfg_list_first(keylist);
+	     element != NULL;
+	     element = cfg_list_next(element))
+	{
+		obj = cfg_listelt_value(element);
+		str = cfg_obj_asstring(obj);
+		newstr = isc_mem_strdup(mctx, str);
+		if (newstr == NULL)
+			goto cleanup;
+		key = isc_mem_get(mctx, sizeof(*key));
+		if (key == NULL)
+			goto cleanup;
+		key->keyname = newstr;
+		key->secret.base = NULL;
+		key->secret.length = 0;
+		ISC_LINK_INIT(key, link);
+		ISC_LIST_APPEND(*keyids, key, link);
+		newstr = NULL;
+	}
+	return (ISC_R_SUCCESS);
+
+ cleanup:
+	if (newstr != NULL)
+		isc_mem_free(mctx, newstr);
+	free_controlkeylist(keyids, mctx);
+	return (ISC_R_NOMEMORY);
+}
+
+static void
+register_keys(const cfg_obj_t *control, const cfg_obj_t *keylist,
+	      controlkeylist_t *keyids, isc_mem_t *mctx, const char *socktext)
+{
+	controlkey_t *keyid, *next;
+	const cfg_obj_t *keydef;
+	char secret[1024];
+	isc_buffer_t b;
+	isc_result_t result;
+
+	/*
+	 * Find the keys corresponding to the keyids used by this listener.
+	 */
+	for (keyid = ISC_LIST_HEAD(*keyids); keyid != NULL; keyid = next) {
+		next = ISC_LIST_NEXT(keyid, link);
+
+		result = cfgkeylist_find(keylist, keyid->keyname, &keydef);
+		if (result != ISC_R_SUCCESS) {
+			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
+				    "couldn't find key '%s' for use with "
+				    "command channel %s",
+				    keyid->keyname, socktext);
+			ISC_LIST_UNLINK(*keyids, keyid, link);
+			free_controlkey(keyid, mctx);
+		} else {
+			const cfg_obj_t *algobj = NULL;
+			const cfg_obj_t *secretobj = NULL;
+			const char *algstr = NULL;
+			const char *secretstr = NULL;
+
+			(void)cfg_map_get(keydef, "algorithm", &algobj);
+			(void)cfg_map_get(keydef, "secret", &secretobj);
+			INSIST(algobj != NULL && secretobj != NULL);
+
+			algstr = cfg_obj_asstring(algobj);
+			secretstr = cfg_obj_asstring(secretobj);
+
+			if (ns_config_getkeyalgorithm(algstr, NULL, NULL) !=
+			    ISC_R_SUCCESS)
+			{
+				cfg_obj_log(control, ns_g_lctx,
+					    ISC_LOG_WARNING,
+					    "unsupported algorithm '%s' in "
+					    "key '%s' for use with command "
+					    "channel %s",
+					    algstr, keyid->keyname, socktext);
+				ISC_LIST_UNLINK(*keyids, keyid, link);
+				free_controlkey(keyid, mctx);
+				continue;
+			}
+
+			isc_buffer_init(&b, secret, sizeof(secret));
+			result = isc_base64_decodestring(secretstr, &b);
+
+			if (result != ISC_R_SUCCESS) {
+				cfg_obj_log(keydef, ns_g_lctx, ISC_LOG_WARNING,
+					    "secret for key '%s' on "
+					    "command channel %s: %s",
+					    keyid->keyname, socktext,
+					    isc_result_totext(result));
+				ISC_LIST_UNLINK(*keyids, keyid, link);
+				free_controlkey(keyid, mctx);
+				continue;
+			}
+
+			keyid->secret.length = isc_buffer_usedlength(&b);
+			keyid->secret.base = isc_mem_get(mctx,
+							 keyid->secret.length);
+			if (keyid->secret.base == NULL) {
+				cfg_obj_log(keydef, ns_g_lctx, ISC_LOG_WARNING,
+					   "couldn't register key '%s': "
+					   "out of memory", keyid->keyname);
+				ISC_LIST_UNLINK(*keyids, keyid, link);
+				free_controlkey(keyid, mctx);
+				break;
+			}
+			memcpy(keyid->secret.base, isc_buffer_base(&b),
+			       keyid->secret.length);
+		}
+	}
+}
+
+#define CHECK(x) \
+	do { \
+		 result = (x); \
+		 if (result != ISC_R_SUCCESS) \
+			goto cleanup; \
+	} while (0)
+
+static isc_result_t
+get_rndckey(isc_mem_t *mctx, controlkeylist_t *keyids) {
+	isc_result_t result;
+	cfg_parser_t *pctx = NULL;
+	cfg_obj_t *config = NULL;
+	const cfg_obj_t *key = NULL;
+	const cfg_obj_t *algobj = NULL;
+	const cfg_obj_t *secretobj = NULL;
+	const char *algstr = NULL;
+	const char *secretstr = NULL;
+	controlkey_t *keyid = NULL;
+	char secret[1024];
+	isc_buffer_t b;
+
+	CHECK(cfg_parser_create(mctx, ns_g_lctx, &pctx));
+	CHECK(cfg_parse_file(pctx, ns_g_keyfile, &cfg_type_rndckey, &config));
+	CHECK(cfg_map_get(config, "key", &key));
+
+	keyid = isc_mem_get(mctx, sizeof(*keyid));
+	if (keyid == NULL)
+		CHECK(ISC_R_NOMEMORY);
+	keyid->keyname = isc_mem_strdup(mctx,
+					cfg_obj_asstring(cfg_map_getname(key)));
+	keyid->secret.base = NULL;
+	keyid->secret.length = 0;
+	ISC_LINK_INIT(keyid, link);
+	if (keyid->keyname == NULL)
+		CHECK(ISC_R_NOMEMORY);
+
+	CHECK(bind9_check_key(key, ns_g_lctx));
+
+	(void)cfg_map_get(key, "algorithm", &algobj);
+	(void)cfg_map_get(key, "secret", &secretobj);
+	INSIST(algobj != NULL && secretobj != NULL);
+
+	algstr = cfg_obj_asstring(algobj);
+	secretstr = cfg_obj_asstring(secretobj);
+
+	if (ns_config_getkeyalgorithm(algstr, NULL, NULL) != ISC_R_SUCCESS) {
+		cfg_obj_log(key, ns_g_lctx,
+			    ISC_LOG_WARNING,
+			    "unsupported algorithm '%s' in "
+			    "key '%s' for use with command "
+			    "channel",
+			    algstr, keyid->keyname);
+		goto cleanup;
+	}
+
+	isc_buffer_init(&b, secret, sizeof(secret));
+	result = isc_base64_decodestring(secretstr, &b);
+
+	if (result != ISC_R_SUCCESS) {
+		cfg_obj_log(key, ns_g_lctx, ISC_LOG_WARNING,
+			    "secret for key '%s' on command channel: %s",
+			    keyid->keyname, isc_result_totext(result));
+		CHECK(result);
+	}
+
+	keyid->secret.length = isc_buffer_usedlength(&b);
+	keyid->secret.base = isc_mem_get(mctx,
+					 keyid->secret.length);
+	if (keyid->secret.base == NULL) {
+		cfg_obj_log(key, ns_g_lctx, ISC_LOG_WARNING,
+			   "couldn't register key '%s': "
+			   "out of memory", keyid->keyname);
+		CHECK(ISC_R_NOMEMORY);
+	}
+	memcpy(keyid->secret.base, isc_buffer_base(&b),
+	       keyid->secret.length);
+	ISC_LIST_APPEND(*keyids, keyid, link);
+	keyid = NULL;
+	result = ISC_R_SUCCESS;
+
+  cleanup:
+	if (keyid != NULL)
+		free_controlkey(keyid, mctx);
+	if (config != NULL)
+		cfg_obj_destroy(pctx, &config);
+	if (pctx != NULL)
+		cfg_parser_destroy(&pctx);
+	return (result);
+}
+
+/*
+ * Ensures that both '*global_keylistp' and '*control_keylistp' are
+ * valid or both are NULL.
+ */
+static void
+get_key_info(const cfg_obj_t *config, const cfg_obj_t *control,
+	     const cfg_obj_t **global_keylistp,
+	     const cfg_obj_t **control_keylistp)
+{
+	isc_result_t result;
+	const cfg_obj_t *control_keylist = NULL;
+	const cfg_obj_t *global_keylist = NULL;
+
+	REQUIRE(global_keylistp != NULL && *global_keylistp == NULL);
+	REQUIRE(control_keylistp != NULL && *control_keylistp == NULL);
+
+	control_keylist = cfg_tuple_get(control, "keys");
+
+	if (!cfg_obj_isvoid(control_keylist) &&
+	    cfg_list_first(control_keylist) != NULL) {
+		result = cfg_map_get(config, "key", &global_keylist);
+
+		if (result == ISC_R_SUCCESS) {
+			*global_keylistp = global_keylist;
+			*control_keylistp = control_keylist;
+		}
+	}
+}
+
+static void
+update_listener(ns_controls_t *cp, controllistener_t **listenerp,
+		const cfg_obj_t *control, const cfg_obj_t *config,
+		isc_sockaddr_t *addr, cfg_aclconfctx_t *aclconfctx,
+		const char *socktext, isc_sockettype_t type)
+{
+	controllistener_t *listener;
+	const cfg_obj_t *allow;
+	const cfg_obj_t *global_keylist = NULL;
+	const cfg_obj_t *control_keylist = NULL;
+	dns_acl_t *new_acl = NULL;
+	controlkeylist_t keys;
+	isc_result_t result = ISC_R_SUCCESS;
+
+	for (listener = ISC_LIST_HEAD(cp->listeners);
+	     listener != NULL;
+	     listener = ISC_LIST_NEXT(listener, link))
+		if (isc_sockaddr_equal(addr, &listener->address))
+			break;
+
+	if (listener == NULL) {
+		*listenerp = NULL;
+		return;
+	}
+
+	/*
+	 * There is already a listener for this sockaddr.
+	 * Update the access list and key information.
+	 *
+	 * First try to deal with the key situation.  There are a few
+	 * possibilities:
+	 *  (a)	It had an explicit keylist and still has an explicit keylist.
+	 *  (b)	It had an automagic key and now has an explicit keylist.
+	 *  (c)	It had an explicit keylist and now needs an automagic key.
+	 *  (d) It has an automagic key and still needs the automagic key.
+	 *
+	 * (c) and (d) are the annoying ones.  The caller needs to know
+	 * that it should use the automagic configuration for key information
+	 * in place of the named.conf configuration.
+	 *
+	 * XXXDCL There is one other hazard that has not been dealt with,
+	 * the problem that if a key change is being caused by a control
+	 * channel reload, then the response will be with the new key
+	 * and not able to be decrypted by the client.
+	 */
+	if (control != NULL)
+		get_key_info(config, control, &global_keylist,
+			     &control_keylist);
+
+	if (control_keylist != NULL) {
+		INSIST(global_keylist != NULL);
+
+		ISC_LIST_INIT(keys);
+		result = controlkeylist_fromcfg(control_keylist,
+						listener->mctx, &keys);
+		if (result == ISC_R_SUCCESS) {
+			free_controlkeylist(&listener->keys, listener->mctx);
+			listener->keys = keys;
+			register_keys(control, global_keylist, &listener->keys,
+				      listener->mctx, socktext);
+		}
+	} else {
+		free_controlkeylist(&listener->keys, listener->mctx);
+		result = get_rndckey(listener->mctx, &listener->keys);
+	}
+
+	if (result != ISC_R_SUCCESS && global_keylist != NULL) {
+		/*
+		 * This message might be a little misleading since the
+		 * "new keys" might in fact be identical to the old ones,
+		 * but tracking whether they are identical just for the
+		 * sake of avoiding this message would be too much trouble.
+		 */
+		if (control != NULL)
+			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
+				    "couldn't install new keys for "
+				    "command channel %s: %s",
+				    socktext, isc_result_totext(result));
+		else
+			isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+				      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
+				      "couldn't install new keys for "
+				      "command channel %s: %s",
+				      socktext, isc_result_totext(result));
+	}
+
+	/*
+	 * Now, keep the old access list unless a new one can be made.
+	 */
+	if (control != NULL && type == isc_sockettype_tcp) {
+		allow = cfg_tuple_get(control, "allow");
+		result = cfg_acl_fromconfig(allow, config, ns_g_lctx,
+					    aclconfctx, listener->mctx, 0,
+					    &new_acl);
+	} else {
+		result = dns_acl_any(listener->mctx, &new_acl);
+	}
+
+	if (result == ISC_R_SUCCESS) {
+		dns_acl_detach(&listener->acl);
+		dns_acl_attach(new_acl, &listener->acl);
+		dns_acl_detach(&new_acl);
+		/* XXXDCL say the old acl is still used? */
+	} else if (control != NULL)
+		cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
+			    "couldn't install new acl for "
+			    "command channel %s: %s",
+			    socktext, isc_result_totext(result));
+	else
+		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
+			      "couldn't install new acl for "
+			      "command channel %s: %s",
+			      socktext, isc_result_totext(result));
+
+	if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) {
+		isc_uint32_t perm, owner, group;
+		perm  = cfg_obj_asuint32(cfg_tuple_get(control, "perm"));
+		owner = cfg_obj_asuint32(cfg_tuple_get(control, "owner"));
+		group = cfg_obj_asuint32(cfg_tuple_get(control, "group"));
+		result = ISC_R_SUCCESS;
+		if (listener->perm != perm || listener->owner != owner ||
+		    listener->group != group)
+			result = isc_socket_permunix(&listener->address, perm,
+						     owner, group);
+		if (result == ISC_R_SUCCESS) {
+			listener->perm = perm;
+			listener->owner = owner;
+			listener->group = group;
+		} else if (control != NULL)
+			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
+				    "couldn't update ownership/permission for "
+				    "command channel %s", socktext);
+	}
+
+	*listenerp = listener;
+}
+
+static void
+add_listener(ns_controls_t *cp, controllistener_t **listenerp,
+	     const cfg_obj_t *control, const cfg_obj_t *config,
+	     isc_sockaddr_t *addr, cfg_aclconfctx_t *aclconfctx,
+	     const char *socktext, isc_sockettype_t type)
+{
+	isc_mem_t *mctx = cp->server->mctx;
+	controllistener_t *listener;
+	const cfg_obj_t *allow;
+	const cfg_obj_t *global_keylist = NULL;
+	const cfg_obj_t *control_keylist = NULL;
+	dns_acl_t *new_acl = NULL;
+	isc_result_t result = ISC_R_SUCCESS;
+
+	listener = isc_mem_get(mctx, sizeof(*listener));
+	if (listener == NULL)
+		result = ISC_R_NOMEMORY;
+
+	if (result == ISC_R_SUCCESS) {
+		listener->controls = cp;
+		listener->mctx = mctx;
+		listener->task = cp->server->task;
+		listener->address = *addr;
+		listener->sock = NULL;
+		listener->listening = ISC_FALSE;
+		listener->exiting = ISC_FALSE;
+		listener->acl = NULL;
+		listener->type = type;
+		listener->perm = 0;
+		listener->owner = 0;
+		listener->group = 0;
+		ISC_LINK_INIT(listener, link);
+		ISC_LIST_INIT(listener->keys);
+		ISC_LIST_INIT(listener->connections);
+
+		/*
+		 * Make the acl.
+		 */
+		if (control != NULL && type == isc_sockettype_tcp) {
+			allow = cfg_tuple_get(control, "allow");
+			result = cfg_acl_fromconfig(allow, config, ns_g_lctx,
+						    aclconfctx, mctx, 0,
+						    &new_acl);
+		} else {
+			result = dns_acl_any(mctx, &new_acl);
+		}
+	}
+
+	if (result == ISC_R_SUCCESS) {
+		dns_acl_attach(new_acl, &listener->acl);
+		dns_acl_detach(&new_acl);
+
+		if (config != NULL)
+			get_key_info(config, control, &global_keylist,
+				     &control_keylist);
+
+		if (control_keylist != NULL) {
+			result = controlkeylist_fromcfg(control_keylist,
+							listener->mctx,
+							&listener->keys);
+			if (result == ISC_R_SUCCESS)
+				register_keys(control, global_keylist,
+					      &listener->keys,
+					      listener->mctx, socktext);
+		} else
+			result = get_rndckey(mctx, &listener->keys);
+
+		if (result != ISC_R_SUCCESS && control != NULL)
+			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
+				    "couldn't install keys for "
+				    "command channel %s: %s",
+				    socktext, isc_result_totext(result));
+	}
+
+	if (result == ISC_R_SUCCESS) {
+		int pf = isc_sockaddr_pf(&listener->address);
+		if ((pf == AF_INET && isc_net_probeipv4() != ISC_R_SUCCESS) ||
+#ifdef ISC_PLATFORM_HAVESYSUNH
+		    (pf == AF_UNIX && isc_net_probeunix() != ISC_R_SUCCESS) ||
+#endif
+		    (pf == AF_INET6 && isc_net_probeipv6() != ISC_R_SUCCESS))
+			result = ISC_R_FAMILYNOSUPPORT;
+	}
+
+	if (result == ISC_R_SUCCESS && type == isc_sockettype_unix)
+		isc_socket_cleanunix(&listener->address, ISC_FALSE);
+
+	if (result == ISC_R_SUCCESS)
+		result = isc_socket_create(ns_g_socketmgr,
+					   isc_sockaddr_pf(&listener->address),
+					   type, &listener->sock);
+	if (result == ISC_R_SUCCESS)
+		isc_socket_setname(listener->sock, "control", NULL);
+
+	if (result == ISC_R_SUCCESS)
+		result = isc_socket_bind(listener->sock, &listener->address,
+					 ISC_SOCKET_REUSEADDRESS);
+
+	if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) {
+		listener->perm = cfg_obj_asuint32(cfg_tuple_get(control,
+								"perm"));
+		listener->owner = cfg_obj_asuint32(cfg_tuple_get(control,
+								 "owner"));
+		listener->group = cfg_obj_asuint32(cfg_tuple_get(control,
+								 "group"));
+		result = isc_socket_permunix(&listener->address, listener->perm,
+					     listener->owner, listener->group);
+	}
+	if (result == ISC_R_SUCCESS)
+		result = control_listen(listener);
+
+	if (result == ISC_R_SUCCESS)
+		result = control_accept(listener);
+
+	if (result == ISC_R_SUCCESS) {
+		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+			      NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE,
+			      "command channel listening on %s", socktext);
+		*listenerp = listener;
+
+	} else {
+		if (listener != NULL) {
+			listener->exiting = ISC_TRUE;
+			free_listener(listener);
+		}
+
+		if (control != NULL)
+			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
+				    "couldn't add command channel %s: %s",
+				    socktext, isc_result_totext(result));
+		else
+			isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
+				      NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE,
+				      "couldn't add command channel %s: %s",
+				      socktext, isc_result_totext(result));
+
+		*listenerp = NULL;
+	}
+
+	/* XXXDCL return error results? fail hard? */
+}
+
+isc_result_t
+ns_controls_configure(ns_controls_t *cp, const cfg_obj_t *config,
+		      cfg_aclconfctx_t *aclconfctx)
+{
+	controllistener_t *listener;
+	controllistenerlist_t new_listeners;
+	const cfg_obj_t *controlslist = NULL;
+	const cfg_listelt_t *element, *element2;
+	char socktext[ISC_SOCKADDR_FORMATSIZE];
+
+	ISC_LIST_INIT(new_listeners);
+
+	/*
+	 * Get the list of named.conf 'controls' statements.
+	 */
+	(void)cfg_map_get(config, "controls", &controlslist);
+
+	/*
+	 * Run through the new control channel list, noting sockets that
+	 * are already being listened on and moving them to the new list.
+	 *
+	 * Identifying duplicate addr/port combinations is left to either
+	 * the underlying config code, or to the bind attempt getting an
+	 * address-in-use error.
+	 */
+	if (controlslist != NULL) {
+		for (element = cfg_list_first(controlslist);
+		     element != NULL;
+		     element = cfg_list_next(element)) {
+			const cfg_obj_t *controls;
+			const cfg_obj_t *inetcontrols = NULL;
+
+			controls = cfg_listelt_value(element);
+			(void)cfg_map_get(controls, "inet", &inetcontrols);
+			if (inetcontrols == NULL)
+				continue;
+
+			for (element2 = cfg_list_first(inetcontrols);
+			     element2 != NULL;
+			     element2 = cfg_list_next(element2)) {
+				const cfg_obj_t *control;
+				const cfg_obj_t *obj;
+				isc_sockaddr_t addr;
+
+				/*
+				 * The parser handles BIND 8 configuration file
+				 * syntax, so it allows unix phrases as well
+				 * inet phrases with no keys{} clause.
+				 */
+				control = cfg_listelt_value(element2);
+
+				obj = cfg_tuple_get(control, "address");
+				addr = *cfg_obj_assockaddr(obj);
+				if (isc_sockaddr_getport(&addr) == 0)
+					isc_sockaddr_setport(&addr,
+							     NS_CONTROL_PORT);
+
+				isc_sockaddr_format(&addr, socktext,
+						    sizeof(socktext));
+
+				isc_log_write(ns_g_lctx,
+					      NS_LOGCATEGORY_GENERAL,
+					      NS_LOGMODULE_CONTROL,
+					      ISC_LOG_DEBUG(9),
+					      "processing control channel %s",
+					      socktext);
+
+				update_listener(cp, &listener, control, config,
+						&addr, aclconfctx, socktext,
+						isc_sockettype_tcp);
+
+				if (listener != NULL)
+					/*
+					 * Remove the listener from the old
+					 * list, so it won't be shut down.
+					 */
+					ISC_LIST_UNLINK(cp->listeners,
+							listener, link);
+				else
+					/*
+					 * This is a new listener.
+					 */
+					add_listener(cp, &listener, control,
+						     config, &addr, aclconfctx,
+						     socktext,
+						     isc_sockettype_tcp);
+
+				if (listener != NULL)
+					ISC_LIST_APPEND(new_listeners,
+							listener, link);
+			}
+		}
+		for (element = cfg_list_first(controlslist);
+		     element != NULL;
+		     element = cfg_list_next(element)) {
+			const cfg_obj_t *controls;
+			const cfg_obj_t *unixcontrols = NULL;
+
+			controls = cfg_listelt_value(element);
+			(void)cfg_map_get(controls, "unix", &unixcontrols);
+			if (unixcontrols == NULL)
+				continue;
+
+			for (element2 = cfg_list_first(unixcontrols);
+			     element2 != NULL;
+			     element2 = cfg_list_next(element2)) {
+				const cfg_obj_t *control;
+				const cfg_obj_t *path;
+				isc_sockaddr_t addr;
+				isc_result_t result;
+
+				/*
+				 * The parser handles BIND 8 configuration file
+				 * syntax, so it allows unix phrases as well
+				 * inet phrases with no keys{} clause.
+				 */
+				control = cfg_listelt_value(element2);
+
+				path = cfg_tuple_get(control, "path");
+				result = isc_sockaddr_frompath(&addr,
+						      cfg_obj_asstring(path));
+				if (result != ISC_R_SUCCESS) {
+					isc_log_write(ns_g_lctx,
+					      NS_LOGCATEGORY_GENERAL,
+					      NS_LOGMODULE_CONTROL,
+					      ISC_LOG_DEBUG(9),
+					      "control channel '%s': %s",
+					      cfg_obj_asstring(path),
+					      isc_result_totext(result));
+					continue;
+				}
+
+				isc_log_write(ns_g_lctx,
+					      NS_LOGCATEGORY_GENERAL,
+					      NS_LOGMODULE_CONTROL,
+					      ISC_LOG_DEBUG(9),
+					      "processing control channel '%s'",
+					      cfg_obj_asstring(path));
+
+				update_listener(cp, &listener, control, config,
+						&addr, aclconfctx,
+						cfg_obj_asstring(path),
+						isc_sockettype_unix);
+
+				if (listener != NULL)
+					/*
+					 * Remove the listener from the old
+					 * list, so it won't be shut down.
+					 */
+					ISC_LIST_UNLINK(cp->listeners,
+							listener, link);
+				else
+					/*
+					 * This is a new listener.
+					 */
+					add_listener(cp, &listener, control,
+						     config, &addr, aclconfctx,
+						     cfg_obj_asstring(path),
+						     isc_sockettype_unix);
+
+				if (listener != NULL)
+					ISC_LIST_APPEND(new_listeners,
+							listener, link);
+			}
+		}
+	} else {
+		int i;
+
+		for (i = 0; i < 2; i++) {
+			isc_sockaddr_t addr;
+
+			if (i == 0) {
+				struct in_addr localhost;
+
+				if (isc_net_probeipv4() != ISC_R_SUCCESS)
+					continue;
+				localhost.s_addr = htonl(INADDR_LOOPBACK);
+				isc_sockaddr_fromin(&addr, &localhost, 0);
+			} else {
+				if (isc_net_probeipv6() != ISC_R_SUCCESS)
+					continue;
+				isc_sockaddr_fromin6(&addr,
+						     &in6addr_loopback, 0);
+			}
+			isc_sockaddr_setport(&addr, NS_CONTROL_PORT);
+
+			isc_sockaddr_format(&addr, socktext, sizeof(socktext));
+
+			update_listener(cp, &listener, NULL, NULL,
+					&addr, NULL, socktext,
+					isc_sockettype_tcp);
+
+			if (listener != NULL)
+				/*
+				 * Remove the listener from the old
+				 * list, so it won't be shut down.
+				 */
+				ISC_LIST_UNLINK(cp->listeners,
+						listener, link);
+			else
+				/*
+				 * This is a new listener.
+				 */
+				add_listener(cp, &listener, NULL, NULL,
+					     &addr, NULL, socktext,
+					     isc_sockettype_tcp);
+
+			if (listener != NULL)
+				ISC_LIST_APPEND(new_listeners,
+						listener, link);
+		}
+	}
+
+	/*
+	 * ns_control_shutdown() will stop whatever is on the global
+	 * listeners list, which currently only has whatever sockaddrs
+	 * were in the previous configuration (if any) that do not
+	 * remain in the current configuration.
+	 */
+	controls_shutdown(cp);
+
+	/*
+	 * Put all of the valid listeners on the listeners list.
+	 * Anything already on listeners in the process of shutting
+	 * down will be taken care of by listen_done().
+	 */
+	ISC_LIST_APPENDLIST(cp->listeners, new_listeners, link);
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+ns_controls_create(ns_server_t *server, ns_controls_t **ctrlsp) {
+	isc_mem_t *mctx = server->mctx;
+	isc_result_t result;
+	ns_controls_t *controls = isc_mem_get(mctx, sizeof(*controls));
+
+	if (controls == NULL)
+		return (ISC_R_NOMEMORY);
+	controls->server = server;
+	ISC_LIST_INIT(controls->listeners);
+	controls->shuttingdown = ISC_FALSE;
+	controls->symtab = NULL;
+	result = isccc_cc_createsymtab(&controls->symtab);
+	if (result != ISC_R_SUCCESS) {
+		isc_mem_put(server->mctx, controls, sizeof(*controls));
+		return (result);
+	}
+	*ctrlsp = controls;
+	return (ISC_R_SUCCESS);
+}
+
+void
+ns_controls_destroy(ns_controls_t **ctrlsp) {
+	ns_controls_t *controls = *ctrlsp;
+
+	REQUIRE(ISC_LIST_EMPTY(controls->listeners));
+
+	isccc_symtab_destroy(&controls->symtab);
+	isc_mem_put(controls->server->mctx, controls, sizeof(*controls));
+	*ctrlsp = NULL;
+}