Vendor import ntp 4.2.8.

Reviewed by:	roberto
Security:	VUXML: 4033d826-87dd-11e4-9079-3c970e169bc2
Security:	http://www.kb.cert.org/vuls/id/852879
Security:	CVE-2014-9293
Security	CVE-2014-9294
Security	CVE-2014-9295
Security	CVE-2014-9296

1 files changed, 618 insertions, 181 deletions

diff --git a/lib/isc/task.c b/lib/isc/task.c
index a630173..cd19d2d 100644
--- a/lib/isc/task.c
+++ b/lib/isc/task.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2004-2008  Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 2004-2012  Internet Systems Consortium, Inc. ("ISC")
  * Copyright (C) 1998-2003  Internet Software Consortium.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: task.c,v 1.107 2008/03/27 23:46:57 tbox Exp $ */
+/* $Id$ */
 
 /*! \file
  * \author Principal Author: Bob Halley
@@ -40,9 +40,31 @@
 #include <isc/util.h>
 #include <isc/xml.h>
 
-#ifndef ISC_PLATFORM_USETHREADS
+#ifdef OPENSSL_LEAKS
+#include <openssl/err.h>
+#endif
+
+/*%
+ * For BIND9 internal applications:
+ * when built with threads we use multiple worker threads shared by the whole
+ * application.
+ * when built without threads we share a single global task manager and use
+ * an integrated event loop for socket, timer, and other generic task events.
+ * For generic library:
+ * we don't use either of them: an application can have multiple task managers
+ * whether or not it's threaded, and if the application is threaded each thread
+ * is expected to have a separate manager; no "worker threads" are shared by
+ * the application threads.
+ */
+#ifdef BIND9
+#ifdef ISC_PLATFORM_USETHREADS
+#define USE_WORKER_THREADS
+#else
+#define USE_SHARED_MANAGER
+#endif	/* ISC_PLATFORM_USETHREADS */
+#endif	/* BIND9 */
+
 #include "task_p.h"
-#endif /* ISC_PLATFORM_USETHREADS */
 
 #ifdef ISC_TASK_TRACE
 #define XTRACE(m)		fprintf(stderr, "task %p thread %lu: %s\n", \
@@ -66,7 +88,7 @@ typedef enum {
 	task_state_done
 } task_state_t;
 
-#ifdef HAVE_LIBXML2
+#if defined(HAVE_LIBXML2) && defined(BIND9)
 static const char *statenames[] = {
 	"idle", "ready", "running", "done",
 };
@@ -75,10 +97,13 @@ static const char *statenames[] = {
 #define TASK_MAGIC			ISC_MAGIC('T', 'A', 'S', 'K')
 #define VALID_TASK(t)			ISC_MAGIC_VALID(t, TASK_MAGIC)
 
-struct isc_task {
+typedef struct isc__task isc__task_t;
+typedef struct isc__taskmgr isc__taskmgr_t;
+
+struct isc__task {
 	/* Not locked. */
-	unsigned int			magic;
-	isc_taskmgr_t *			manager;
+	isc_task_t			common;
+	isc__taskmgr_t *		manager;
 	isc_mutex_t			lock;
 	/* Locked by task lock. */
 	task_state_t			state;
@@ -91,11 +116,13 @@ struct isc_task {
 	char				name[16];
 	void *				tag;
 	/* Locked by task manager lock. */
-	LINK(isc_task_t)		link;
-	LINK(isc_task_t)		ready_link;
+	LINK(isc__task_t)		link;
+	LINK(isc__task_t)		ready_link;
+	LINK(isc__task_t)		ready_priority_link;
 };
 
 #define TASK_F_SHUTTINGDOWN		0x01
+#define TASK_F_PRIVILEGED		0x02
 
 #define TASK_SHUTTINGDOWN(t)		(((t)->flags & TASK_F_SHUTTINGDOWN) \
 					 != 0)
@@ -103,9 +130,11 @@ struct isc_task {
 #define TASK_MANAGER_MAGIC		ISC_MAGIC('T', 'S', 'K', 'M')
 #define VALID_MANAGER(m)		ISC_MAGIC_VALID(m, TASK_MANAGER_MAGIC)
 
-struct isc_taskmgr {
+typedef ISC_LIST(isc__task_t)	isc__tasklist_t;
+
+struct isc__taskmgr {
 	/* Not locked. */
-	unsigned int			magic;
+	isc_taskmgr_t			common;
 	isc_mem_t *			mctx;
 	isc_mutex_t			lock;
 #ifdef ISC_PLATFORM_USETHREADS
@@ -114,16 +143,20 @@ struct isc_taskmgr {
 #endif /* ISC_PLATFORM_USETHREADS */
 	/* Locked by task manager lock. */
 	unsigned int			default_quantum;
-	LIST(isc_task_t)		tasks;
-	isc_tasklist_t			ready_tasks;
+	LIST(isc__task_t)		tasks;
+	isc__tasklist_t			ready_tasks;
+	isc__tasklist_t			ready_priority_tasks;
+	isc_taskmgrmode_t		mode;
 #ifdef ISC_PLATFORM_USETHREADS
 	isc_condition_t			work_available;
 	isc_condition_t			exclusive_granted;
+	isc_condition_t			paused;
 #endif /* ISC_PLATFORM_USETHREADS */
 	unsigned int			tasks_running;
+	isc_boolean_t			pause_requested;
 	isc_boolean_t			exclusive_requested;
 	isc_boolean_t			exiting;
-#ifndef ISC_PLATFORM_USETHREADS
+#ifdef USE_SHARED_MANAGER
 	unsigned int			refs;
 #endif /* ISC_PLATFORM_USETHREADS */
 };
@@ -132,17 +165,137 @@ struct isc_taskmgr {
 #define DEFAULT_DEFAULT_QUANTUM		5
 #define FINISHED(m)			((m)->exiting && EMPTY((m)->tasks))
 
-#ifndef ISC_PLATFORM_USETHREADS
-static isc_taskmgr_t *taskmgr = NULL;
-#endif /* ISC_PLATFORM_USETHREADS */
+#ifdef USE_SHARED_MANAGER
+static isc__taskmgr_t *taskmgr = NULL;
+#endif /* USE_SHARED_MANAGER */
+
+/*%
+ * The following can be either static or public, depending on build environment.
+ */
+
+#ifdef BIND9
+#define ISC_TASKFUNC_SCOPE
+#else
+#define ISC_TASKFUNC_SCOPE static
+#endif
+
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__task_create(isc_taskmgr_t *manager0, unsigned int quantum,
+		 isc_task_t **taskp);
+ISC_TASKFUNC_SCOPE void
+isc__task_attach(isc_task_t *source0, isc_task_t **targetp);
+ISC_TASKFUNC_SCOPE void
+isc__task_detach(isc_task_t **taskp);
+ISC_TASKFUNC_SCOPE void
+isc__task_send(isc_task_t *task0, isc_event_t **eventp);
+ISC_TASKFUNC_SCOPE void
+isc__task_sendanddetach(isc_task_t **taskp, isc_event_t **eventp);
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_purgerange(isc_task_t *task0, void *sender, isc_eventtype_t first,
+		     isc_eventtype_t last, void *tag);
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_purge(isc_task_t *task, void *sender, isc_eventtype_t type,
+		void *tag);
+ISC_TASKFUNC_SCOPE isc_boolean_t
+isc__task_purgeevent(isc_task_t *task0, isc_event_t *event);
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_unsendrange(isc_task_t *task, void *sender, isc_eventtype_t first,
+		      isc_eventtype_t last, void *tag,
+		      isc_eventlist_t *events);
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_unsend(isc_task_t *task, void *sender, isc_eventtype_t type,
+		 void *tag, isc_eventlist_t *events);
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__task_onshutdown(isc_task_t *task0, isc_taskaction_t action,
+		     const void *arg);
+ISC_TASKFUNC_SCOPE void
+isc__task_shutdown(isc_task_t *task0);
+ISC_TASKFUNC_SCOPE void
+isc__task_destroy(isc_task_t **taskp);
+ISC_TASKFUNC_SCOPE void
+isc__task_setname(isc_task_t *task0, const char *name, void *tag);
+ISC_TASKFUNC_SCOPE const char *
+isc__task_getname(isc_task_t *task0);
+ISC_TASKFUNC_SCOPE void *
+isc__task_gettag(isc_task_t *task0);
+ISC_TASKFUNC_SCOPE void
+isc__task_getcurrenttime(isc_task_t *task0, isc_stdtime_t *t);
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__taskmgr_create(isc_mem_t *mctx, unsigned int workers,
+		    unsigned int default_quantum, isc_taskmgr_t **managerp);
+ISC_TASKFUNC_SCOPE void
+isc__taskmgr_destroy(isc_taskmgr_t **managerp);
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__task_beginexclusive(isc_task_t *task);
+ISC_TASKFUNC_SCOPE void
+isc__task_endexclusive(isc_task_t *task0);
+ISC_TASKFUNC_SCOPE void
+isc__task_setprivilege(isc_task_t *task0, isc_boolean_t priv);
+ISC_TASKFUNC_SCOPE isc_boolean_t
+isc__task_privilege(isc_task_t *task0);
+ISC_TASKFUNC_SCOPE void
+isc__taskmgr_setmode(isc_taskmgr_t *manager0, isc_taskmgrmode_t mode);
+ISC_TASKFUNC_SCOPE isc_taskmgrmode_t
+isc__taskmgr_mode(isc_taskmgr_t *manager0);
+
+static inline isc_boolean_t
+empty_readyq(isc__taskmgr_t *manager);
+
+static inline isc__task_t *
+pop_readyq(isc__taskmgr_t *manager);
+
+static inline void
+push_readyq(isc__taskmgr_t *manager, isc__task_t *task);
+
+static struct isc__taskmethods {
+	isc_taskmethods_t methods;
+
+	/*%
+	 * The following are defined just for avoiding unused static functions.
+	 */
+#ifndef BIND9
+	void *purgeevent, *unsendrange, *getname, *gettag, *getcurrenttime;
+#endif
+} taskmethods = {
+	{
+		isc__task_attach,
+		isc__task_detach,
+		isc__task_destroy,
+		isc__task_send,
+		isc__task_sendanddetach,
+		isc__task_unsend,
+		isc__task_onshutdown,
+		isc__task_shutdown,
+		isc__task_setname,
+		isc__task_purge,
+		isc__task_purgerange,
+		isc__task_beginexclusive,
+		isc__task_endexclusive,
+		isc__task_setprivilege,
+		isc__task_privilege
+	}
+#ifndef BIND9
+	,
+	(void *)isc__task_purgeevent, (void *)isc__task_unsendrange,
+	(void *)isc__task_getname, (void *)isc__task_gettag,
+	(void *)isc__task_getcurrenttime
+#endif
+};
+
+static isc_taskmgrmethods_t taskmgrmethods = {
+	isc__taskmgr_destroy,
+	isc__taskmgr_setmode,
+	isc__taskmgr_mode,
+	isc__task_create
+};
 
 /***
  *** Tasks.
  ***/
 
 static void
-task_finished(isc_task_t *task) {
-	isc_taskmgr_t *manager = task->manager;
+task_finished(isc__task_t *task) {
+	isc__taskmgr_t *manager = task->manager;
 
 	REQUIRE(EMPTY(task->events));
 	REQUIRE(EMPTY(task->on_shutdown));
@@ -153,7 +306,7 @@ task_finished(isc_task_t *task) {
 
 	LOCK(&manager->lock);
 	UNLINK(manager->tasks, task, link);
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
 	if (FINISHED(manager)) {
 		/*
 		 * All tasks have completed and the
@@ -163,19 +316,21 @@ task_finished(isc_task_t *task) {
 		 */
 		BROADCAST(&manager->work_available);
 	}
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_WORKER_THREADS */
 	UNLOCK(&manager->lock);
 
 	DESTROYLOCK(&task->lock);
-	task->magic = 0;
+	task->common.impmagic = 0;
+	task->common.magic = 0;
 	isc_mem_put(manager->mctx, task, sizeof(*task));
 }
 
-isc_result_t
-isc_task_create(isc_taskmgr_t *manager, unsigned int quantum,
-		isc_task_t **taskp)
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__task_create(isc_taskmgr_t *manager0, unsigned int quantum,
+		 isc_task_t **taskp)
 {
-	isc_task_t *task;
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
+	isc__task_t *task;
 	isc_boolean_t exiting;
 	isc_result_t result;
 
@@ -186,12 +341,14 @@ isc_task_create(isc_taskmgr_t *manager, unsigned int quantum,
 	if (task == NULL)
 		return (ISC_R_NOMEMORY);
 	XTRACE("isc_task_create");
-	task->manager = manager;
 	result = isc_mutex_init(&task->lock);
 	if (result != ISC_R_SUCCESS) {
 		isc_mem_put(manager->mctx, task, sizeof(*task));
 		return (result);
 	}
+	LOCK(&manager->lock);
+	LOCK(&task->lock);	/* helps coverity analysis noise ratio */
+	task->manager = manager;
 	task->state = task_state_idle;
 	task->references = 1;
 	INIT_LIST(task->events);
@@ -203,6 +360,9 @@ isc_task_create(isc_taskmgr_t *manager, unsigned int quantum,
 	task->tag = NULL;
 	INIT_LINK(task, link);
 	INIT_LINK(task, ready_link);
+	INIT_LINK(task, ready_priority_link);
+	UNLOCK(&task->lock);
+	UNLOCK(&manager->lock);
 
 	exiting = ISC_FALSE;
 	LOCK(&manager->lock);
@@ -220,14 +380,17 @@ isc_task_create(isc_taskmgr_t *manager, unsigned int quantum,
 		return (ISC_R_SHUTTINGDOWN);
 	}
 
-	task->magic = TASK_MAGIC;
-	*taskp = task;
+	task->common.methods = (isc_taskmethods_t *)&taskmethods;
+	task->common.magic = ISCAPI_TASK_MAGIC;
+	task->common.impmagic = TASK_MAGIC;
+	*taskp = (isc_task_t *)task;
 
 	return (ISC_R_SUCCESS);
 }
 
-void
-isc_task_attach(isc_task_t *source, isc_task_t **targetp) {
+ISC_TASKFUNC_SCOPE void
+isc__task_attach(isc_task_t *source0, isc_task_t **targetp) {
+	isc__task_t *source = (isc__task_t *)source0;
 
 	/*
 	 * Attach *targetp to source.
@@ -242,11 +405,11 @@ isc_task_attach(isc_task_t *source, isc_task_t **targetp) {
 	source->references++;
 	UNLOCK(&source->lock);
 
-	*targetp = source;
+	*targetp = (isc_task_t *)source;
 }
 
 static inline isc_boolean_t
-task_shutdown(isc_task_t *task) {
+task_shutdown(isc__task_t *task) {
 	isc_boolean_t was_idle = ISC_FALSE;
 	isc_event_t *event, *prev;
 
@@ -267,6 +430,7 @@ task_shutdown(isc_task_t *task) {
 		}
 		INSIST(task->state == task_state_ready ||
 		       task->state == task_state_running);
+
 		/*
 		 * Note that we post shutdown events LIFO.
 		 */
@@ -282,9 +446,17 @@ task_shutdown(isc_task_t *task) {
 	return (was_idle);
 }
 
+/*
+ * Moves a task onto the appropriate run queue.
+ *
+ * Caller must NOT hold manager lock.
+ */
 static inline void
-task_ready(isc_task_t *task) {
-	isc_taskmgr_t *manager = task->manager;
+task_ready(isc__task_t *task) {
+	isc__taskmgr_t *manager = task->manager;
+#ifdef USE_WORKER_THREADS
+	isc_boolean_t has_privilege = isc__task_privilege((isc_task_t *) task);
+#endif /* USE_WORKER_THREADS */
 
 	REQUIRE(VALID_MANAGER(manager));
 	REQUIRE(task->state == task_state_ready);
@@ -292,17 +464,16 @@ task_ready(isc_task_t *task) {
 	XTRACE("task_ready");
 
 	LOCK(&manager->lock);
-
-	ENQUEUE(manager->ready_tasks, task, ready_link);
-#ifdef ISC_PLATFORM_USETHREADS
-	SIGNAL(&manager->work_available);
-#endif /* ISC_PLATFORM_USETHREADS */
-
+	push_readyq(manager, task);
+#ifdef USE_WORKER_THREADS
+	if (manager->mode == isc_taskmgrmode_normal || has_privilege)
+		SIGNAL(&manager->work_available);
+#endif /* USE_WORKER_THREADS */
 	UNLOCK(&manager->lock);
 }
 
 static inline isc_boolean_t
-task_detach(isc_task_t *task) {
+task_detach(isc__task_t *task) {
 
 	/*
 	 * Caller must be holding the task lock.
@@ -330,9 +501,9 @@ task_detach(isc_task_t *task) {
 	return (ISC_FALSE);
 }
 
-void
-isc_task_detach(isc_task_t **taskp) {
-	isc_task_t *task;
+ISC_TASKFUNC_SCOPE void
+isc__task_detach(isc_task_t **taskp) {
+	isc__task_t *task;
 	isc_boolean_t was_idle;
 
 	/*
@@ -340,7 +511,7 @@ isc_task_detach(isc_task_t **taskp) {
 	 */
 
 	REQUIRE(taskp != NULL);
-	task = *taskp;
+	task = (isc__task_t *)*taskp;
 	REQUIRE(VALID_TASK(task));
 
 	XTRACE("isc_task_detach");
@@ -356,7 +527,7 @@ isc_task_detach(isc_task_t **taskp) {
 }
 
 static inline isc_boolean_t
-task_send(isc_task_t *task, isc_event_t **eventp) {
+task_send(isc__task_t *task, isc_event_t **eventp) {
 	isc_boolean_t was_idle = ISC_FALSE;
 	isc_event_t *event;
 
@@ -385,8 +556,9 @@ task_send(isc_task_t *task, isc_event_t **eventp) {
 	return (was_idle);
 }
 
-void
-isc_task_send(isc_task_t *task, isc_event_t **eventp) {
+ISC_TASKFUNC_SCOPE void
+isc__task_send(isc_task_t *task0, isc_event_t **eventp) {
+	isc__task_t *task = (isc__task_t *)task0;
 	isc_boolean_t was_idle;
 
 	/*
@@ -426,10 +598,10 @@ isc_task_send(isc_task_t *task, isc_event_t **eventp) {
 	}
 }
 
-void
-isc_task_sendanddetach(isc_task_t **taskp, isc_event_t **eventp) {
+ISC_TASKFUNC_SCOPE void
+isc__task_sendanddetach(isc_task_t **taskp, isc_event_t **eventp) {
 	isc_boolean_t idle1, idle2;
-	isc_task_t *task;
+	isc__task_t *task;
 
 	/*
 	 * Send '*event' to '*taskp' and then detach '*taskp' from its
@@ -437,7 +609,7 @@ isc_task_sendanddetach(isc_task_t **taskp, isc_event_t **eventp) {
 	 */
 
 	REQUIRE(taskp != NULL);
-	task = *taskp;
+	task = (isc__task_t *)*taskp;
 	REQUIRE(VALID_TASK(task));
 
 	XTRACE("isc_task_sendanddetach");
@@ -463,7 +635,7 @@ isc_task_sendanddetach(isc_task_t **taskp, isc_event_t **eventp) {
 #define PURGE_OK(event)	(((event)->ev_attributes & ISC_EVENTATTR_NOPURGE) == 0)
 
 static unsigned int
-dequeue_events(isc_task_t *task, void *sender, isc_eventtype_t first,
+dequeue_events(isc__task_t *task, void *sender, isc_eventtype_t first,
 	       isc_eventtype_t last, void *tag,
 	       isc_eventlist_t *events, isc_boolean_t purging)
 {
@@ -502,10 +674,11 @@ dequeue_events(isc_task_t *task, void *sender, isc_eventtype_t first,
 	return (count);
 }
 
-unsigned int
-isc_task_purgerange(isc_task_t *task, void *sender, isc_eventtype_t first,
-		    isc_eventtype_t last, void *tag)
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_purgerange(isc_task_t *task0, void *sender, isc_eventtype_t first,
+		     isc_eventtype_t last, void *tag)
 {
+	isc__task_t *task = (isc__task_t *)task0;
 	unsigned int count;
 	isc_eventlist_t events;
 	isc_event_t *event, *next_event;
@@ -533,9 +706,9 @@ isc_task_purgerange(isc_task_t *task, void *sender, isc_eventtype_t first,
 	return (count);
 }
 
-unsigned int
-isc_task_purge(isc_task_t *task, void *sender, isc_eventtype_t type,
-	       void *tag)
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_purge(isc_task_t *task, void *sender, isc_eventtype_t type,
+		void *tag)
 {
 	/*
 	 * Purge events from a task's event queue.
@@ -543,11 +716,12 @@ isc_task_purge(isc_task_t *task, void *sender, isc_eventtype_t type,
 
 	XTRACE("isc_task_purge");
 
-	return (isc_task_purgerange(task, sender, type, type, tag));
+	return (isc__task_purgerange(task, sender, type, type, tag));
 }
 
-isc_boolean_t
-isc_task_purgeevent(isc_task_t *task, isc_event_t *event) {
+ISC_TASKFUNC_SCOPE isc_boolean_t
+isc__task_purgeevent(isc_task_t *task0, isc_event_t *event) {
+	isc__task_t *task = (isc__task_t *)task0;
 	isc_event_t *curr_event, *next_event;
 
 	/*
@@ -588,10 +762,10 @@ isc_task_purgeevent(isc_task_t *task, isc_event_t *event) {
 	return (ISC_TRUE);
 }
 
-unsigned int
-isc_task_unsendrange(isc_task_t *task, void *sender, isc_eventtype_t first,
-		     isc_eventtype_t last, void *tag,
-		     isc_eventlist_t *events)
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_unsendrange(isc_task_t *task, void *sender, isc_eventtype_t first,
+		      isc_eventtype_t last, void *tag,
+		      isc_eventlist_t *events)
 {
 	/*
 	 * Remove events from a task's event queue.
@@ -599,13 +773,13 @@ isc_task_unsendrange(isc_task_t *task, void *sender, isc_eventtype_t first,
 
 	XTRACE("isc_task_unsendrange");
 
-	return (dequeue_events(task, sender, first, last, tag, events,
-			       ISC_FALSE));
+	return (dequeue_events((isc__task_t *)task, sender, first,
+			       last, tag, events, ISC_FALSE));
 }
 
-unsigned int
-isc_task_unsend(isc_task_t *task, void *sender, isc_eventtype_t type,
-		void *tag, isc_eventlist_t *events)
+ISC_TASKFUNC_SCOPE unsigned int
+isc__task_unsend(isc_task_t *task, void *sender, isc_eventtype_t type,
+		 void *tag, isc_eventlist_t *events)
 {
 	/*
 	 * Remove events from a task's event queue.
@@ -613,13 +787,15 @@ isc_task_unsend(isc_task_t *task, void *sender, isc_eventtype_t type,
 
 	XTRACE("isc_task_unsend");
 
-	return (dequeue_events(task, sender, type, type, tag, events,
-			       ISC_FALSE));
+	return (dequeue_events((isc__task_t *)task, sender, type,
+			       type, tag, events, ISC_FALSE));
 }
 
-isc_result_t
-isc_task_onshutdown(isc_task_t *task, isc_taskaction_t action, const void *arg)
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__task_onshutdown(isc_task_t *task0, isc_taskaction_t action,
+		     const void *arg)
 {
+	isc__task_t *task = (isc__task_t *)task0;
 	isc_boolean_t disallowed = ISC_FALSE;
 	isc_result_t result = ISC_R_SUCCESS;
 	isc_event_t *event;
@@ -655,8 +831,9 @@ isc_task_onshutdown(isc_task_t *task, isc_taskaction_t action, const void *arg)
 	return (result);
 }
 
-void
-isc_task_shutdown(isc_task_t *task) {
+ISC_TASKFUNC_SCOPE void
+isc__task_shutdown(isc_task_t *task0) {
+	isc__task_t *task = (isc__task_t *)task0;
 	isc_boolean_t was_idle;
 
 	/*
@@ -673,8 +850,8 @@ isc_task_shutdown(isc_task_t *task) {
 		task_ready(task);
 }
 
-void
-isc_task_destroy(isc_task_t **taskp) {
+ISC_TASKFUNC_SCOPE void
+isc__task_destroy(isc_task_t **taskp) {
 
 	/*
 	 * Destroy '*taskp'.
@@ -686,8 +863,9 @@ isc_task_destroy(isc_task_t **taskp) {
 	isc_task_detach(taskp);
 }
 
-void
-isc_task_setname(isc_task_t *task, const char *name, void *tag) {
+ISC_TASKFUNC_SCOPE void
+isc__task_setname(isc_task_t *task0, const char *name, void *tag) {
+	isc__task_t *task = (isc__task_t *)task0;
 
 	/*
 	 * Name 'task'.
@@ -702,38 +880,108 @@ isc_task_setname(isc_task_t *task, const char *name, void *tag) {
 	UNLOCK(&task->lock);
 }
 
-const char *
-isc_task_getname(isc_task_t *task) {
+ISC_TASKFUNC_SCOPE const char *
+isc__task_getname(isc_task_t *task0) {
+	isc__task_t *task = (isc__task_t *)task0;
+
+	REQUIRE(VALID_TASK(task));
+
 	return (task->name);
 }
 
-void *
-isc_task_gettag(isc_task_t *task) {
+ISC_TASKFUNC_SCOPE void *
+isc__task_gettag(isc_task_t *task0) {
+	isc__task_t *task = (isc__task_t *)task0;
+
+	REQUIRE(VALID_TASK(task));
+
 	return (task->tag);
 }
 
-void
-isc_task_getcurrenttime(isc_task_t *task, isc_stdtime_t *t) {
+ISC_TASKFUNC_SCOPE void
+isc__task_getcurrenttime(isc_task_t *task0, isc_stdtime_t *t) {
+	isc__task_t *task = (isc__task_t *)task0;
+
 	REQUIRE(VALID_TASK(task));
 	REQUIRE(t != NULL);
 
 	LOCK(&task->lock);
-
 	*t = task->now;
-
 	UNLOCK(&task->lock);
 }
 
 /***
  *** Task Manager.
  ***/
+
+/*
+ * Return ISC_TRUE if the current ready list for the manager, which is
+ * either ready_tasks or the ready_priority_tasks, depending on whether
+ * the manager is currently in normal or privileged execution mode.
+ *
+ * Caller must hold the task manager lock.
+ */
+static inline isc_boolean_t
+empty_readyq(isc__taskmgr_t *manager) {
+	isc__tasklist_t queue;
+
+	if (manager->mode == isc_taskmgrmode_normal)
+		queue = manager->ready_tasks;
+	else
+		queue = manager->ready_priority_tasks;
+
+	return (ISC_TF(EMPTY(queue)));
+}
+
+/*
+ * Dequeue and return a pointer to the first task on the current ready
+ * list for the manager.
+ * If the task is privileged, dequeue it from the other ready list
+ * as well.
+ *
+ * Caller must hold the task manager lock.
+ */
+static inline isc__task_t *
+pop_readyq(isc__taskmgr_t *manager) {
+	isc__task_t *task;
+
+	if (manager->mode == isc_taskmgrmode_normal)
+		task = HEAD(manager->ready_tasks);
+	else
+		task = HEAD(manager->ready_priority_tasks);
+
+	if (task != NULL) {
+		DEQUEUE(manager->ready_tasks, task, ready_link);
+		if (ISC_LINK_LINKED(task, ready_priority_link))
+			DEQUEUE(manager->ready_priority_tasks, task,
+				ready_priority_link);
+	}
+
+	return (task);
+}
+
+/*
+ * Push 'task' onto the ready_tasks queue.  If 'task' has the privilege
+ * flag set, then also push it onto the ready_priority_tasks queue.
+ *
+ * Caller must hold the task manager lock.
+ */
+static inline void
+push_readyq(isc__taskmgr_t *manager, isc__task_t *task) {
+	ENQUEUE(manager->ready_tasks, task, ready_link);
+	if ((task->flags & TASK_F_PRIVILEGED) != 0)
+		ENQUEUE(manager->ready_priority_tasks, task,
+			ready_priority_link);
+}
+
 static void
-dispatch(isc_taskmgr_t *manager) {
-	isc_task_t *task;
-#ifndef ISC_PLATFORM_USETHREADS
+dispatch(isc__taskmgr_t *manager) {
+	isc__task_t *task;
+#ifndef USE_WORKER_THREADS
 	unsigned int total_dispatch_count = 0;
-	isc_tasklist_t ready_tasks;
-#endif /* ISC_PLATFORM_USETHREADS */
+	isc__tasklist_t new_ready_tasks;
+	isc__tasklist_t new_priority_tasks;
+#endif /* USE_WORKER_THREADS */
 
 	REQUIRE(VALID_MANAGER(manager));
 
@@ -787,22 +1035,26 @@ dispatch(isc_taskmgr_t *manager) {
 	 * unlocks.  The while expression is always protected by the lock.
 	 */
 
-#ifndef ISC_PLATFORM_USETHREADS
-	ISC_LIST_INIT(ready_tasks);
+#ifndef USE_WORKER_THREADS
+	ISC_LIST_INIT(new_ready_tasks);
+	ISC_LIST_INIT(new_priority_tasks);
 #endif
 	LOCK(&manager->lock);
+
 	while (!FINISHED(manager)) {
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
 		/*
 		 * For reasons similar to those given in the comment in
 		 * isc_task_send() above, it is safe for us to dequeue
 		 * the task while only holding the manager lock, and then
 		 * change the task to running state while only holding the
 		 * task lock.
+		 *
+		 * If a pause has been requested, don't do any work
+		 * until it's been released.
 		 */
-		while ((EMPTY(manager->ready_tasks) ||
-			manager->exclusive_requested) &&
-			!FINISHED(manager))
+		while ((empty_readyq(manager) || manager->pause_requested ||
+			manager->exclusive_requested) && !FINISHED(manager))
 		{
 			XTHREADTRACE(isc_msgcat_get(isc_msgcat,
 						    ISC_MSGSET_GENERAL,
@@ -812,15 +1064,15 @@ dispatch(isc_taskmgr_t *manager) {
 						    ISC_MSGSET_TASK,
 						    ISC_MSG_AWAKE, "awake"));
 		}
-#else /* ISC_PLATFORM_USETHREADS */
+#else /* USE_WORKER_THREADS */
 		if (total_dispatch_count >= DEFAULT_TASKMGR_QUANTUM ||
-		    EMPTY(manager->ready_tasks))
+		    empty_readyq(manager))
 			break;
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_WORKER_THREADS */
 		XTHREADTRACE(isc_msgcat_get(isc_msgcat, ISC_MSGSET_TASK,
 					    ISC_MSG_WORKING, "working"));
 
-		task = HEAD(manager->ready_tasks);
+		task = pop_readyq(manager);
 		if (task != NULL) {
 			unsigned int dispatch_count = 0;
 			isc_boolean_t done = ISC_FALSE;
@@ -835,7 +1087,6 @@ dispatch(isc_taskmgr_t *manager) {
 			 * have a task to do.  We must reacquire the manager
 			 * lock before exiting the 'if (task != NULL)' block.
 			 */
-			DEQUEUE(manager->ready_tasks, task, ready_link);
 			manager->tasks_running++;
 			UNLOCK(&manager->lock);
 
@@ -859,13 +1110,15 @@ dispatch(isc_taskmgr_t *manager) {
 							    "execute action"));
 					if (event->ev_action != NULL) {
 						UNLOCK(&task->lock);
-						(event->ev_action)(task,event);
+						(event->ev_action)(
+							(isc_task_t *)task,
+							event);
 						LOCK(&task->lock);
 					}
 					dispatch_count++;
-#ifndef ISC_PLATFORM_USETHREADS
+#ifndef USE_WORKER_THREADS
 					total_dispatch_count++;
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_WORKER_THREADS */
 				}
 
 				if (task->references == 0 &&
@@ -950,12 +1203,15 @@ dispatch(isc_taskmgr_t *manager) {
 
 			LOCK(&manager->lock);
 			manager->tasks_running--;
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
 			if (manager->exclusive_requested &&
 			    manager->tasks_running == 1) {
 				SIGNAL(&manager->exclusive_granted);
+			} else if (manager->pause_requested &&
+				   manager->tasks_running == 0) {
+				SIGNAL(&manager->paused);
 			}
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_WORKER_THREADS */
 			if (requeue) {
 				/*
 				 * We know we're awake, so we don't have
@@ -976,28 +1232,50 @@ dispatch(isc_taskmgr_t *manager) {
 				 * were usually nonempty, the 'optimization'
 				 * might even hurt rather than help.
 				 */
-#ifdef ISC_PLATFORM_USETHREADS
-				ENQUEUE(manager->ready_tasks, task,
-					ready_link);
+#ifdef USE_WORKER_THREADS
+				push_readyq(manager, task);
 #else
-				ENQUEUE(ready_tasks, task, ready_link);
+				ENQUEUE(new_ready_tasks, task, ready_link);
+				if ((task->flags & TASK_F_PRIVILEGED) != 0)
+					ENQUEUE(new_priority_tasks, task,
+						ready_priority_link);
 #endif
 			}
 		}
+
+#ifdef USE_WORKER_THREADS
+		/*
+		 * If we are in privileged execution mode and there are no
+		 * tasks remaining on the current ready queue, then
+		 * we're stuck.  Automatically drop privileges at that
+		 * point and continue with the regular ready queue.
+		 */
+		if (manager->tasks_running == 0 && empty_readyq(manager)) {
+			manager->mode = isc_taskmgrmode_normal;
+			if (!empty_readyq(manager))
+				BROADCAST(&manager->work_available);
+		}
+#endif
 	}
-#ifndef ISC_PLATFORM_USETHREADS
-	ISC_LIST_APPENDLIST(manager->ready_tasks, ready_tasks, ready_link);
+
+#ifndef USE_WORKER_THREADS
+	ISC_LIST_APPENDLIST(manager->ready_tasks, new_ready_tasks, ready_link);
+	ISC_LIST_APPENDLIST(manager->ready_priority_tasks, new_priority_tasks,
+			    ready_priority_link);
+	if (empty_readyq(manager))
+		manager->mode = isc_taskmgrmode_normal;
 #endif
+
 	UNLOCK(&manager->lock);
 }
 
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
 static isc_threadresult_t
 #ifdef _WIN32
 WINAPI
 #endif
 run(void *uap) {
-	isc_taskmgr_t *manager = uap;
+	isc__taskmgr_t *manager = uap;
 
 	XTHREADTRACE(isc_msgcat_get(isc_msgcat, ISC_MSGSET_GENERAL,
 				    ISC_MSG_STARTING, "starting"));
@@ -1007,33 +1285,45 @@ run(void *uap) {
 	XTHREADTRACE(isc_msgcat_get(isc_msgcat, ISC_MSGSET_GENERAL,
 				    ISC_MSG_EXITING, "exiting"));
 
+#ifdef OPENSSL_LEAKS
+	ERR_remove_state(0);
+#endif
+
 	return ((isc_threadresult_t)0);
 }
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_WORKER_THREADS */
 
 static void
-manager_free(isc_taskmgr_t *manager) {
+manager_free(isc__taskmgr_t *manager) {
 	isc_mem_t *mctx;
 
-#ifdef ISC_PLATFORM_USETHREADS
+	LOCK(&manager->lock);
+#ifdef USE_WORKER_THREADS
 	(void)isc_condition_destroy(&manager->exclusive_granted);
 	(void)isc_condition_destroy(&manager->work_available);
+	(void)isc_condition_destroy(&manager->paused);
 	isc_mem_free(manager->mctx, manager->threads);
-#endif /* ISC_PLATFORM_USETHREADS */
-	DESTROYLOCK(&manager->lock);
-	manager->magic = 0;
+#endif /* USE_WORKER_THREADS */
+	manager->common.impmagic = 0;
+	manager->common.magic = 0;
 	mctx = manager->mctx;
+	UNLOCK(&manager->lock);
+	DESTROYLOCK(&manager->lock);
 	isc_mem_put(mctx, manager, sizeof(*manager));
 	isc_mem_detach(&mctx);
+
+#ifdef USE_SHARED_MANAGER
+	taskmgr = NULL;
+#endif	/* USE_SHARED_MANAGER */
 }
 
-isc_result_t
-isc_taskmgr_create(isc_mem_t *mctx, unsigned int workers,
-		   unsigned int default_quantum, isc_taskmgr_t **managerp)
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__taskmgr_create(isc_mem_t *mctx, unsigned int workers,
+		    unsigned int default_quantum, isc_taskmgr_t **managerp)
 {
 	isc_result_t result;
 	unsigned int i, started = 0;
-	isc_taskmgr_t *manager;
+	isc__taskmgr_t *manager;
 
 	/*
 	 * Create a new task manager.
@@ -1042,28 +1332,35 @@ isc_taskmgr_create(isc_mem_t *mctx, unsigned int workers,
 	REQUIRE(workers > 0);
 	REQUIRE(managerp != NULL && *managerp == NULL);
 
-#ifndef ISC_PLATFORM_USETHREADS
+#ifndef USE_WORKER_THREADS
 	UNUSED(i);
 	UNUSED(started);
-	UNUSED(workers);
+#endif
 
+#ifdef USE_SHARED_MANAGER
 	if (taskmgr != NULL) {
+		if (taskmgr->refs == 0)
+			return (ISC_R_SHUTTINGDOWN);
 		taskmgr->refs++;
-		*managerp = taskmgr;
+		*managerp = (isc_taskmgr_t *)taskmgr;
 		return (ISC_R_SUCCESS);
 	}
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_SHARED_MANAGER */
 
 	manager = isc_mem_get(mctx, sizeof(*manager));
 	if (manager == NULL)
 		return (ISC_R_NOMEMORY);
-	manager->magic = TASK_MANAGER_MAGIC;
+	manager->common.methods = &taskmgrmethods;
+	manager->common.impmagic = TASK_MANAGER_MAGIC;
+	manager->common.magic = ISCAPI_TASKMGR_MAGIC;
+	manager->mode = isc_taskmgrmode_normal;
 	manager->mctx = NULL;
 	result = isc_mutex_init(&manager->lock);
 	if (result != ISC_R_SUCCESS)
 		goto cleanup_mgr;
+	LOCK(&manager->lock);
 
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
 	manager->workers = 0;
 	manager->threads = isc_mem_allocate(mctx,
 					    workers * sizeof(isc_thread_t));
@@ -1087,20 +1384,29 @@ isc_taskmgr_create(isc_mem_t *mctx, unsigned int workers,
 		result = ISC_R_UNEXPECTED;
 		goto cleanup_workavailable;
 	}
-#endif /* ISC_PLATFORM_USETHREADS */
+	if (isc_condition_init(&manager->paused) != ISC_R_SUCCESS) {
+		UNEXPECTED_ERROR(__FILE__, __LINE__,
+				 "isc_condition_init() %s",
+				 isc_msgcat_get(isc_msgcat, ISC_MSGSET_GENERAL,
+						ISC_MSG_FAILED, "failed"));
+		result = ISC_R_UNEXPECTED;
+		goto cleanup_exclusivegranted;
+	}
+#endif /* USE_WORKER_THREADS */
 	if (default_quantum == 0)
 		default_quantum = DEFAULT_DEFAULT_QUANTUM;
 	manager->default_quantum = default_quantum;
 	INIT_LIST(manager->tasks);
 	INIT_LIST(manager->ready_tasks);
+	INIT_LIST(manager->ready_priority_tasks);
 	manager->tasks_running = 0;
 	manager->exclusive_requested = ISC_FALSE;
+	manager->pause_requested = ISC_FALSE;
 	manager->exiting = ISC_FALSE;
 
 	isc_mem_attach(mctx, &manager->mctx);
 
-#ifdef ISC_PLATFORM_USETHREADS
-	LOCK(&manager->lock);
+#ifdef USE_WORKER_THREADS
 	/*
 	 * Start workers.
 	 */
@@ -1119,21 +1425,26 @@ isc_taskmgr_create(isc_mem_t *mctx, unsigned int workers,
 		return (ISC_R_NOTHREADS);
 	}
 	isc_thread_setconcurrency(workers);
-#else /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_WORKER_THREADS */
+#ifdef USE_SHARED_MANAGER
 	manager->refs = 1;
+	UNLOCK(&manager->lock);
 	taskmgr = manager;
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif /* USE_SHARED_MANAGER */
 
-	*managerp = manager;
+	*managerp = (isc_taskmgr_t *)manager;
 
 	return (ISC_R_SUCCESS);
 
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
+ cleanup_exclusivegranted:
+	(void)isc_condition_destroy(&manager->exclusive_granted);
  cleanup_workavailable:
 	(void)isc_condition_destroy(&manager->work_available);
  cleanup_threads:
 	isc_mem_free(mctx, manager->threads);
  cleanup_lock:
+	UNLOCK(&manager->lock);
 	DESTROYLOCK(&manager->lock);
 #endif
  cleanup_mgr:
@@ -1141,10 +1452,10 @@ isc_taskmgr_create(isc_mem_t *mctx, unsigned int workers,
 	return (result);
 }
 
-void
-isc_taskmgr_destroy(isc_taskmgr_t **managerp) {
-	isc_taskmgr_t *manager;
-	isc_task_t *task;
+ISC_TASKFUNC_SCOPE void
+isc__taskmgr_destroy(isc_taskmgr_t **managerp) {
+	isc__taskmgr_t *manager;
+	isc__task_t *task;
 	unsigned int i;
 
 	/*
@@ -1152,18 +1463,20 @@ isc_taskmgr_destroy(isc_taskmgr_t **managerp) {
 	 */
 
 	REQUIRE(managerp != NULL);
-	manager = *managerp;
+	manager = (isc__taskmgr_t *)*managerp;
 	REQUIRE(VALID_MANAGER(manager));
 
-#ifndef ISC_PLATFORM_USETHREADS
+#ifndef USE_WORKER_THREADS
 	UNUSED(i);
+#endif /* USE_WORKER_THREADS */
 
-	if (manager->refs > 1) {
-		manager->refs--;
+#ifdef USE_SHARED_MANAGER
+	manager->refs--;
+	if (manager->refs > 0) {
 		*managerp = NULL;
 		return;
 	}
-#endif /* ISC_PLATFORM_USETHREADS */
+#endif
 
 	XTHREADTRACE("isc_taskmgr_destroy");
 	/*
@@ -1192,6 +1505,11 @@ isc_taskmgr_destroy(isc_taskmgr_t **managerp) {
 	manager->exiting = ISC_TRUE;
 
 	/*
+	 * If privileged mode was on, turn it off.
+	 */
+	manager->mode = isc_taskmgrmode_normal;
+
+	/*
 	 * Post shutdown event(s) to every task (if they haven't already been
 	 * posted).
 	 */
@@ -1200,10 +1518,10 @@ isc_taskmgr_destroy(isc_taskmgr_t **managerp) {
 	     task = NEXT(task, link)) {
 		LOCK(&task->lock);
 		if (task_shutdown(task))
-			ENQUEUE(manager->ready_tasks, task, ready_link);
+			push_readyq(manager, task);
 		UNLOCK(&task->lock);
 	}
-#ifdef ISC_PLATFORM_USETHREADS
+#ifdef USE_WORKER_THREADS
 	/*
 	 * Wake up any sleeping workers.  This ensures we get work done if
 	 * there's work left to do, and if there are already no tasks left
@@ -1217,36 +1535,76 @@ isc_taskmgr_destroy(isc_taskmgr_t **managerp) {
 	 */
 	for (i = 0; i < manager->workers; i++)
 		(void)isc_thread_join(manager->threads[i], NULL);
-#else /* ISC_PLATFORM_USETHREADS */
+#else /* USE_WORKER_THREADS */
 	/*
 	 * Dispatch the shutdown events.
 	 */
 	UNLOCK(&manager->lock);
-	while (isc__taskmgr_ready())
-		(void)isc__taskmgr_dispatch();
+	while (isc__taskmgr_ready((isc_taskmgr_t *)manager))
+		(void)isc__taskmgr_dispatch((isc_taskmgr_t *)manager);
+#ifdef BIND9
 	if (!ISC_LIST_EMPTY(manager->tasks))
 		isc_mem_printallactive(stderr);
+#endif
 	INSIST(ISC_LIST_EMPTY(manager->tasks));
-#endif /* ISC_PLATFORM_USETHREADS */
+#ifdef USE_SHARED_MANAGER
+	taskmgr = NULL;
+#endif
+#endif /* USE_WORKER_THREADS */
 
 	manager_free(manager);
 
 	*managerp = NULL;
 }
 
-#ifndef ISC_PLATFORM_USETHREADS
+ISC_TASKFUNC_SCOPE void
+isc__taskmgr_setmode(isc_taskmgr_t *manager0, isc_taskmgrmode_t mode) {
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
+
+	LOCK(&manager->lock);
+	manager->mode = mode;
+	UNLOCK(&manager->lock);
+}
+
+ISC_TASKFUNC_SCOPE isc_taskmgrmode_t
+isc__taskmgr_mode(isc_taskmgr_t *manager0) {
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
+	isc_taskmgrmode_t mode;
+	LOCK(&manager->lock);
+	mode = manager->mode;
+	UNLOCK(&manager->lock);
+	return (mode);
+}
+
+#ifndef USE_WORKER_THREADS
 isc_boolean_t
-isc__taskmgr_ready(void) {
-	if (taskmgr == NULL)
+isc__taskmgr_ready(isc_taskmgr_t *manager0) {
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
+	isc_boolean_t is_ready;
+
+#ifdef USE_SHARED_MANAGER
+	if (manager == NULL)
+		manager = taskmgr;
+#endif
+	if (manager == NULL)
 		return (ISC_FALSE);
-	return (ISC_TF(!ISC_LIST_EMPTY(taskmgr->ready_tasks)));
+
+	LOCK(&manager->lock);
+	is_ready = !empty_readyq(manager);
+	UNLOCK(&manager->lock);
+
+	return (is_ready);
 }
 
 isc_result_t
-isc__taskmgr_dispatch(void) {
-	isc_taskmgr_t *manager = taskmgr;
+isc__taskmgr_dispatch(isc_taskmgr_t *manager0) {
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
 
-	if (taskmgr == NULL)
+#ifdef USE_SHARED_MANAGER
+	if (manager == NULL)
+		manager = taskmgr;
+#endif
+	if (manager == NULL)
 		return (ISC_R_NOTFOUND);
 
 	dispatch(manager);
@@ -1254,12 +1612,36 @@ isc__taskmgr_dispatch(void) {
 	return (ISC_R_SUCCESS);
 }
 
-#endif /* ISC_PLATFORM_USETHREADS */
+#else
+ISC_TASKFUNC_SCOPE void
+isc__taskmgr_pause(isc_taskmgr_t *manager0) {
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
+	LOCK(&manager->lock);
+	while (manager->tasks_running > 0) {
+		WAIT(&manager->paused, &manager->lock);
+	}
+	manager->pause_requested = ISC_TRUE;
+	UNLOCK(&manager->lock);
+}
 
-isc_result_t
-isc_task_beginexclusive(isc_task_t *task) {
-#ifdef ISC_PLATFORM_USETHREADS
-	isc_taskmgr_t *manager = task->manager;
+ISC_TASKFUNC_SCOPE void
+isc__taskmgr_resume(isc_taskmgr_t *manager0) {
+	isc__taskmgr_t *manager = (isc__taskmgr_t *)manager0;
+
+	LOCK(&manager->lock);
+	if (manager->pause_requested) {
+		manager->pause_requested = ISC_FALSE;
+		BROADCAST(&manager->work_available);
+	}
+	UNLOCK(&manager->lock);
+}
+#endif /* USE_WORKER_THREADS */
+
+ISC_TASKFUNC_SCOPE isc_result_t
+isc__task_beginexclusive(isc_task_t *task0) {
+#ifdef USE_WORKER_THREADS
+	isc__task_t *task = (isc__task_t *)task0;
+	isc__taskmgr_t *manager = task->manager;
 	REQUIRE(task->state == task_state_running);
 	LOCK(&manager->lock);
 	if (manager->exclusive_requested) {
@@ -1272,15 +1654,17 @@ isc_task_beginexclusive(isc_task_t *task) {
 	}
 	UNLOCK(&manager->lock);
 #else
-	UNUSED(task);
+	UNUSED(task0);
 #endif
 	return (ISC_R_SUCCESS);
 }
 
-void
-isc_task_endexclusive(isc_task_t *task) {
-#ifdef ISC_PLATFORM_USETHREADS
-	isc_taskmgr_t *manager = task->manager;
+ISC_TASKFUNC_SCOPE void
+isc__task_endexclusive(isc_task_t *task0) {
+#ifdef USE_WORKER_THREADS
+	isc__task_t *task = (isc__task_t *)task0;
+	isc__taskmgr_t *manager = task->manager;
+
 	REQUIRE(task->state == task_state_running);
 	LOCK(&manager->lock);
 	REQUIRE(manager->exclusive_requested);
@@ -1288,16 +1672,69 @@ isc_task_endexclusive(isc_task_t *task) {
 	BROADCAST(&manager->work_available);
 	UNLOCK(&manager->lock);
 #else
-	UNUSED(task);
+	UNUSED(task0);
+#endif
+}
+
+ISC_TASKFUNC_SCOPE void
+isc__task_setprivilege(isc_task_t *task0, isc_boolean_t priv) {
+	isc__task_t *task = (isc__task_t *)task0;
+	isc__taskmgr_t *manager = task->manager;
+	isc_boolean_t oldpriv;
+
+	LOCK(&task->lock);
+	oldpriv = ISC_TF((task->flags & TASK_F_PRIVILEGED) != 0);
+	if (priv)
+		task->flags |= TASK_F_PRIVILEGED;
+	else
+		task->flags &= ~TASK_F_PRIVILEGED;
+	UNLOCK(&task->lock);
+
+	if (priv == oldpriv)
+		return;
+
+	LOCK(&manager->lock);
+	if (priv && ISC_LINK_LINKED(task, ready_link))
+		ENQUEUE(manager->ready_priority_tasks, task,
+			ready_priority_link);
+	else if (!priv && ISC_LINK_LINKED(task, ready_priority_link))
+		DEQUEUE(manager->ready_priority_tasks, task,
+			ready_priority_link);
+	UNLOCK(&manager->lock);
+}
+
+ISC_TASKFUNC_SCOPE isc_boolean_t
+isc__task_privilege(isc_task_t *task0) {
+	isc__task_t *task = (isc__task_t *)task0;
+	isc_boolean_t priv;
+
+	LOCK(&task->lock);
+	priv = ISC_TF((task->flags & TASK_F_PRIVILEGED) != 0);
+	UNLOCK(&task->lock);
+	return (priv);
+}
+
+#ifdef USE_SOCKETIMPREGISTER
+isc_result_t
+isc__task_register() {
+	return (isc_task_register(isc__taskmgr_create));
+}
 #endif
+
+isc_boolean_t
+isc_task_exiting(isc_task_t *t) {
+	isc__task_t *task = (isc__task_t *)t;
+
+	REQUIRE(VALID_TASK(task));
+	return (TASK_SHUTTINGDOWN(task));
 }
 
-#ifdef HAVE_LIBXML2
 
+#if defined(HAVE_LIBXML2) && defined(BIND9)
 void
-isc_taskmgr_renderxml(isc_taskmgr_t *mgr, xmlTextWriterPtr writer)
-{
-	isc_task_t *task;
+isc_taskmgr_renderxml(isc_taskmgr_t *mgr0, xmlTextWriterPtr writer) {
+	isc__taskmgr_t *mgr = (isc__taskmgr_t *)mgr0;
+	isc__task_t *task;
 
 	LOCK(&mgr->lock);
 
@@ -1373,4 +1810,4 @@ isc_taskmgr_renderxml(isc_taskmgr_t *mgr, xmlTextWriterPtr writer)
 
 	UNLOCK(&mgr->lock);
 }
-#endif /* HAVE_LIBXML2 */
+#endif /* HAVE_LIBXML2 && BIND9 */