Merge branch '4425-current-level-of-tcp-clients-missing-from-statistics-channel-v9_18' into 'bind-9.18'

[9.18] Expose the TCP client count in statistics channel

See merge request isc-projects/bind9!8660

CHANGES

@@ -33,6 +33,9 @@
 			listener transport type. Thanks to Thomas Amgarten.
 			[GL #4518] [GL #4528]
 
+6325.	[func]		Expose the TCP client count in statistics channel.
+			[GL #4425]
+
 6324.	[bug]		Fix a possible crash in 'dig +nssearch +nofail' and
 			'host -C' commands when one of the name servers returns
 			SERVFAIL. [GL #4508]

bin/named/statschannel.c

@@ -626,6 +626,11 @@ init_desc(void) {
 	SET_SOCKSTATDESC(unixactive, "Unix domain sockets active",
 			 "UnixActive");
 	SET_SOCKSTATDESC(rawactive, "Raw sockets active", "RawActive");
+	SET_SOCKSTATDESC(tcp4clients, "TCP/IPv4 clients currently connected",
+			 "TCP4Clients");
+	SET_SOCKSTATDESC(tcp6clients, "TCP/IPv6 clients currently connected",
+			 "TCP6Clients");
+
 	INSIST(i == isc_sockstatscounter_max);
 
 	/* Initialize DNSSEC statistics */

doc/notes/notes-current.rst

@@ -20,7 +20,8 @@ Security Fixes
 New Features
 ~~~~~~~~~~~~
 
-- None.
+- The statistics channel now includes counters that indicate the number
+  of currently connected TCP IPv4/IPv6 clients. :gl:`#4425`
 
 Removed Features
 ~~~~~~~~~~~~~~~~

lib/isc/include/isc/stats.h

@@ -100,7 +100,10 @@ enum {
 	isc_sockstatscounter_rawrecvfail = 60,
 	isc_sockstatscounter_rawactive = 61,
 
-	isc_sockstatscounter_max = 62
+	isc_sockstatscounter_tcp4clients = 62,
+	isc_sockstatscounter_tcp6clients = 63,
+
+	isc_sockstatscounter_max = 64
 };
 
 ISC_LANG_BEGINDECLS

lib/isc/netmgr/netmgr-int.h

@@ -856,7 +856,8 @@ typedef enum {
 	STATID_SENDFAIL = 8,
 	STATID_RECVFAIL = 9,
 	STATID_ACTIVE = 10,
-	STATID_MAX = 11,
+	STATID_CLIENTS = 11,
+	STATID_MAX = 12,
 } isc__nm_statid_t;
 
 #if HAVE_LIBNGHTTP2

lib/isc/netmgr/netmgr.c

@@ -67,7 +67,8 @@ static const isc_statscounter_t udp4statsindex[] = {
 	-1,
 	isc_sockstatscounter_udp4sendfail,
 	isc_sockstatscounter_udp4recvfail,
-	isc_sockstatscounter_udp4active
+	isc_sockstatscounter_udp4active,
+	-1,
 };
 
 static const isc_statscounter_t udp6statsindex[] = {
@@ -81,7 +82,8 @@ static const isc_statscounter_t udp6statsindex[] = {
 	-1,
 	isc_sockstatscounter_udp6sendfail,
 	isc_sockstatscounter_udp6recvfail,
-	isc_sockstatscounter_udp6active
+	isc_sockstatscounter_udp6active,
+	-1,
 };
 
 static const isc_statscounter_t tcp4statsindex[] = {
@@ -90,7 +92,7 @@ static const isc_statscounter_t tcp4statsindex[] = {
 	isc_sockstatscounter_tcp4connectfail, isc_sockstatscounter_tcp4connect,
 	isc_sockstatscounter_tcp4acceptfail,  isc_sockstatscounter_tcp4accept,
 	isc_sockstatscounter_tcp4sendfail,    isc_sockstatscounter_tcp4recvfail,
-	isc_sockstatscounter_tcp4active
+	isc_sockstatscounter_tcp4active,      isc_sockstatscounter_tcp4clients,
 };
 
 static const isc_statscounter_t tcp6statsindex[] = {
@@ -99,7 +101,7 @@ static const isc_statscounter_t tcp6statsindex[] = {
 	isc_sockstatscounter_tcp6connectfail, isc_sockstatscounter_tcp6connect,
 	isc_sockstatscounter_tcp6acceptfail,  isc_sockstatscounter_tcp6accept,
 	isc_sockstatscounter_tcp6sendfail,    isc_sockstatscounter_tcp6recvfail,
-	isc_sockstatscounter_tcp6active
+	isc_sockstatscounter_tcp6active,      isc_sockstatscounter_tcp6clients,
 };
 
 #if 0

lib/isc/netmgr/tcpdns.c

@@ -689,6 +689,7 @@ destroy:
 	 * chance to be executed.
 	 */
 	if (sock->quota != NULL) {
+		isc__nm_decstats(sock, STATID_CLIENTS);
 		isc_quota_detach(&sock->quota);
 	}
 }
@@ -1004,6 +1005,8 @@ accept_connection(isc_nmsocket_t *ssock, isc_quota_t *quota) {
 	UV_RUNTIME_CHECK(uv_timer_init, r);
 	uv_handle_set_data((uv_handle_t *)&csock->read_timer, csock);
 
+	isc__nm_incstats(csock, STATID_CLIENTS);
+
 	r = uv_accept(&ssock->uv_handle.stream, &csock->uv_handle.stream);
 	if (r != 0) {
 		result = isc__nm_uverr2result(r);
@@ -1366,6 +1369,7 @@ tcpdns_close_direct(isc_nmsocket_t *sock) {
 	REQUIRE(atomic_load(&sock->closing));
 
 	if (sock->quota != NULL) {
+		isc__nm_decstats(sock, STATID_CLIENTS);
 		isc_quota_detach(&sock->quota);
 	}
 

lib/isc/netmgr/tlsdns.c

@@ -895,6 +895,7 @@ destroy:
 	 * had a chance to be executed.
 	 */
 	if (sock->quota != NULL) {
+		isc__nm_decstats(sock, STATID_CLIENTS);
 		isc_quota_detach(&sock->quota);
 	}
 }
@@ -1628,6 +1629,8 @@ accept_connection(isc_nmsocket_t *ssock, isc_quota_t *quota) {
 	UV_RUNTIME_CHECK(uv_timer_init, r);
 	uv_handle_set_data((uv_handle_t *)&csock->read_timer, csock);
 
+	isc__nm_incstats(csock, STATID_CLIENTS);
+
 	r = uv_accept(&ssock->uv_handle.stream, &csock->uv_handle.stream);
 	if (r != 0) {
 		result = isc__nm_uverr2result(r);
@@ -2109,6 +2112,7 @@ tlsdns_close_direct(isc_nmsocket_t *sock) {
 	REQUIRE(sock->tls.pending_req == NULL);
 
 	if (sock->quota != NULL) {
+		isc__nm_decstats(sock, STATID_CLIENTS);
 		isc_quota_detach(&sock->quota);
 	}