Make sure the unit test listening and connecting ports are different

In rare circumstances, the UDP port for the listening socket and the UDP
port for the connecting socket might be the same.  Because we use the
"reuse" port socket option, this isn't caught when binding the socket,
and thus the connected client socket could send a datagram to itself,
completely bypassing the server.  This doesn't happen under normal
operation mode because `named` is listening on a privileged port (53),
and even if not, it doesn't usually talk to itself as the tests do.

Pick an arbitrary port for listening (9153-9156) that is outside the
ephemeral port range for the network manager related unit tests (except
the `doh_test).

tests/isc/netmgr_common.c

@@ -95,69 +95,20 @@ bool allow_send_back = false;
 bool noanswer = false;
 bool stream_use_TLS = false;
 bool stream = false;
+in_port_t stream_port = 0;
 
 isc_nm_recv_cb_t connect_readcb = NULL;
 
-int
-setup_ephemeral_port(isc_sockaddr_t *addr, sa_family_t family) {
-	socklen_t addrlen = sizeof(*addr);
-	uv_os_sock_t fd = -1;
-	int r;
-
-	isc_sockaddr_fromin6(addr, &in6addr_loopback, 0);
-
-	fd = socket(AF_INET6, family, 0);
-	if (fd < 0) {
-		perror("setup_ephemeral_port: socket()");
-		return (-1);
-	}
-
-	r = bind(fd, (const struct sockaddr *)&addr->type.sa,
-		 sizeof(addr->type.sin6));
-	if (r != 0) {
-		perror("setup_ephemeral_port: bind()");
-		isc__nm_closesocket(fd);
-		return (r);
-	}
-
-	r = getsockname(fd, (struct sockaddr *)&addr->type.sa, &addrlen);
-	if (r != 0) {
-		perror("setup_ephemeral_port: getsockname()");
-		isc__nm_closesocket(fd);
-		return (r);
-	}
-
-#if IPV6_RECVERR
-#define setsockopt_on(socket, level, name) \
-	setsockopt(socket, level, name, &(int){ 1 }, sizeof(int))
-
-	r = setsockopt_on(fd, IPPROTO_IPV6, IPV6_RECVERR);
-	if (r != 0) {
-		perror("setup_ephemeral_port");
-		isc__nm_closesocket(fd);
-		return (r);
-	}
-#endif
-
-	return (fd);
-}
-
 int
 setup_netmgr_test(void **state) {
 	char *env_workers = getenv("ISC_TASK_WORKERS");
-	uv_os_sock_t tcp_listen_sock = -1;
 	size_t nworkers;
 
 	tcp_connect_addr = (isc_sockaddr_t){ .length = 0 };
 	isc_sockaddr_fromin6(&tcp_connect_addr, &in6addr_loopback, 0);
 
 	tcp_listen_addr = (isc_sockaddr_t){ .length = 0 };
-	tcp_listen_sock = setup_ephemeral_port(&tcp_listen_addr, SOCK_STREAM);
-	if (tcp_listen_sock < 0) {
-		return (-1);
-	}
-	isc__nm_closesocket(tcp_listen_sock);
-	tcp_listen_sock = -1;
+	isc_sockaddr_fromin6(&tcp_listen_addr, &in6addr_loopback, stream_port);
 
 	if (env_workers != NULL) {
 		workers = atoi(env_workers);

tests/isc/netmgr_common.h

@@ -18,6 +18,16 @@
 
 #include "netmgr/netmgr-int.h"
 
+/*
+ * Pick unused port outside the ephemeral port range, so we don't clash with
+ * connected sockets.
+ */
+#define UDP_TEST_PORT	 9153
+#define TCP_TEST_PORT	 9154
+#define TLS_TEST_PORT	 9155
+#define TCPDNS_TEST_PORT 9156
+#define TLSDNS_TEST_PORT 9157
+
 typedef void (*stream_connect_function)(isc_nm_t *nm);
 typedef void (*connect_func)(isc_nm_t *);
 
@@ -119,6 +129,7 @@ extern bool allow_send_back;
 extern bool noanswer;
 extern bool stream_use_TLS;
 extern bool stream;
+extern in_port_t stream_port;
 
 extern isc_nm_recv_cb_t connect_readcb;
 
@@ -213,9 +224,6 @@ extern isc_nm_recv_cb_t connect_readcb;
 #define atomic_assert_int_ge(val, exp) assert_true(atomic_load(&val) >= exp)
 #define atomic_assert_int_gt(val, exp) assert_true(atomic_load(&val) > exp)
 
-int
-setup_ephemeral_port(isc_sockaddr_t *addr, sa_family_t family);
-
 int
 setup_netmgr_test(void **state);
 int

tests/isc/tcp_test.c

@@ -132,6 +132,7 @@ ISC_TEST_LIST_END
 
 static int
 tcp_setup(void **state __attribute__((__unused__))) {
+	stream_port = TCP_TEST_PORT;
 	stream_use_TLS = false;
 	stream = true;
 

tests/isc/tcpdns_test.c

@@ -142,4 +142,12 @@ ISC_TEST_ENTRY_CUSTOM(tcpdns_recv_send, stream_recv_send_setup,
 		      stream_recv_send_teardown)
 
 ISC_TEST_LIST_END
-ISC_TEST_MAIN
+
+static int
+tcpdns_setup(void **state __attribute__((__unused__))) {
+	stream_port = TCPDNS_TEST_PORT;
+
+	return (0);
+}
+
+ISC_TEST_MAIN_CUSTOM(tcpdns_setup, NULL)

tests/isc/tls_test.c

@@ -131,6 +131,7 @@ ISC_TEST_LIST_END
 
 static int
 tls_setup(void **state __attribute__((__unused__))) {
+	stream_port = TLS_TEST_PORT;
 	stream_use_TLS = true;
 	stream = true;
 

tests/isc/tlsdns_test.c

@@ -147,4 +147,12 @@ ISC_TEST_ENTRY_CUSTOM(tlsdns_recv_send, stream_recv_send_setup,
 /* FIXME: Re-add the noalpn tests */
 
 ISC_TEST_LIST_END
-ISC_TEST_MAIN
+
+static int
+tlsdns_setup(void **state __attribute__((__unused__))) {
+	stream_port = TCPDNS_TEST_PORT;
+
+	return (0);
+}
+
+ISC_TEST_MAIN_CUSTOM(tlsdns_setup, NULL)

tests/isc/udp_test.c

@@ -56,8 +56,6 @@ static isc_sockaddr_t udp_connect_addr;
 
 static int
 setup_test(void **state) {
-	uv_os_sock_t udp_listen_sock = -1;
-
 	setup_loopmgr(state);
 	setup_netmgr(state);
 
@@ -65,11 +63,8 @@ setup_test(void **state) {
 	isc_sockaddr_fromin6(&udp_connect_addr, &in6addr_loopback, 0);
 
 	udp_listen_addr = (isc_sockaddr_t){ .length = 0 };
-	udp_listen_sock = setup_ephemeral_port(&udp_listen_addr, SOCK_DGRAM);
-	if (udp_listen_sock < 0) {
-		return (-1);
-	}
-	isc__nm_closesocket(udp_listen_sock);
+	isc_sockaddr_fromin6(&udp_listen_addr, &in6addr_loopback,
+			     UDP_TEST_PORT);
 
 	atomic_store(&sreads, 0);
 	atomic_store(&ssends, 0);