Merge branch 'use network helpers, part 8'

Geliang Tang says:

====================
v11:
 - new patches 2, 4, 6.
 - drop expect_errno from network_helper_opts as Eduard and Martin
   suggested.
 - drop sockmap_ktls patches from this set.

v10:
 - a new patch 10 is added.
 - patches 1-6, 8-9 unchanged, only commit logs updated.
 - "err = -errno" is used in patches 7, 11, 12 to get the real error
   number before checking value of "err".

v9:
 - new patches 5-7, new struct member expect_errno for network_helper_opts.
 - patches 1-4, 8-9 unchanged.
 - update patches 10-11 to make sure all tests pass.

v8:
 - only patch 8 updated, to fix errors reported by CI.

v7:
 - address Martin's comments in v6. (thanks)
 - use MAX(opts->backlog, 0) instead of opts->backlog.
 - use connect_to_fd_opts instead connect_to_fd.
 - more ASSERT_* to check errors.

v6:
 - update patch 6 as Daniel suggested. (thanks)

v5:
 - keep make_server and make_client as Eduard suggested.

v4:
 - a new patch to use make_sockaddr in sockmap_ktls.
 - a new patch to close fd in error path in drop_on_reuseport.
 - drop make_server() in patch 7.
 - drop make_client() too in patch 9.

v3:
 - a new patch to add backlog for network_helper_opts.
 - use start_server_str in sockmap_ktls now, not start_server.

v2:
 - address Eduard's comments in v1. (thanks)
 - fix errors reported by CI.

This patch set uses network helpers in sk_lookup, and drop the local
helpers inetaddr_len() and make_socket().
====================
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

tools/testing/selftests/bpf/network_helpers.c

@@ -106,7 +106,7 @@ static int __start_server(int type, const struct sockaddr *addr, socklen_t addrl
 	}
 
 	if (type == SOCK_STREAM) {
-		if (listen(fd, 1) < 0) {
+		if (listen(fd, opts->backlog ? MAX(opts->backlog, 0) : 1) < 0) {
 			log_err("Failed to listed on socket");
 			goto error_close;
 		}

tools/testing/selftests/bpf/network_helpers.h

@@ -25,6 +25,16 @@ struct network_helper_opts {
 	int timeout_ms;
 	bool must_fail;
 	int proto;
+	/* +ve: Passed to listen() as-is.
+	 *   0: Default when the test does not set
+	 *      a particular value during the struct init.
+	 *      It is changed to 1 before passing to listen().
+	 *      Most tests only have one on-going connection.
+	 * -ve: It is changed to 0 before passing to listen().
+	 *      It is useful to force syncookie without
+	 *	changing the "tcp_syncookies" sysctl from 1 to 2.
+	 */
+	int backlog;
 	int (*post_socket_cb)(int fd, void *opts);
 	void *cb_opts;
 };

tools/testing/selftests/bpf/prog_tests/sk_lookup.c

@@ -77,6 +77,12 @@ struct test {
 	bool reuseport_has_conns; /* Add a connected socket to reuseport group */
 };
 
+struct cb_opts {
+	int family;
+	int sotype;
+	bool reuseport;
+};
+
 static __u32 duration;		/* for CHECK macro */
 
 static bool is_ipv6(const char *ip)
@@ -142,19 +148,14 @@ static int make_socket(int sotype, const char *ip, int port,
 	return fd;
 }
 
-static int make_server(int sotype, const char *ip, int port,
-		       struct bpf_program *reuseport_prog)
+static int setsockopts(int fd, void *opts)
 {
-	struct sockaddr_storage addr = {0};
+	struct cb_opts *co = (struct cb_opts *)opts;
 	const int one = 1;
-	int err, fd = -1;
-
-	fd = make_socket(sotype, ip, port, &addr);
-	if (fd < 0)
-		return -1;
+	int err = 0;
 
 	/* Enabled for UDPv6 sockets for IPv4-mapped IPv6 to work. */
-	if (sotype == SOCK_DGRAM) {
+	if (co->sotype == SOCK_DGRAM) {
 		err = setsockopt(fd, SOL_IP, IP_RECVORIGDSTADDR, &one,
 				 sizeof(one));
 		if (CHECK(err, "setsockopt(IP_RECVORIGDSTADDR)", "failed\n")) {
@@ -163,7 +164,7 @@ static int make_server(int sotype, const char *ip, int port,
 		}
 	}
 
-	if (sotype == SOCK_DGRAM && addr.ss_family == AF_INET6) {
+	if (co->sotype == SOCK_DGRAM && co->family == AF_INET6) {
 		err = setsockopt(fd, SOL_IPV6, IPV6_RECVORIGDSTADDR, &one,
 				 sizeof(one));
 		if (CHECK(err, "setsockopt(IPV6_RECVORIGDSTADDR)", "failed\n")) {
@@ -172,7 +173,7 @@ static int make_server(int sotype, const char *ip, int port,
 		}
 	}
 
-	if (sotype == SOCK_STREAM) {
+	if (co->sotype == SOCK_STREAM) {
 		err = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one,
 				 sizeof(one));
 		if (CHECK(err, "setsockopt(SO_REUSEADDR)", "failed\n")) {
@@ -181,7 +182,7 @@ static int make_server(int sotype, const char *ip, int port,
 		}
 	}
 
-	if (reuseport_prog) {
+	if (co->reuseport) {
 		err = setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one,
 				 sizeof(one));
 		if (CHECK(err, "setsockopt(SO_REUSEPORT)", "failed\n")) {
@@ -190,19 +191,28 @@ static int make_server(int sotype, const char *ip, int port,
 		}
 	}
 
-	err = bind(fd, (void *)&addr, inetaddr_len(&addr));
-	if (CHECK(err, "bind", "failed\n")) {
-		log_err("failed to bind listen socket");
-		goto fail;
-	}
+fail:
+	return err;
+}
 
-	if (sotype == SOCK_STREAM) {
-		err = listen(fd, SOMAXCONN);
-		if (CHECK(err, "make_server", "listen")) {
-			log_err("failed to listen on port %d", port);
-			goto fail;
-		}
-	}
+static int make_server(int sotype, const char *ip, int port,
+		       struct bpf_program *reuseport_prog)
+{
+	struct cb_opts cb_opts = {
+		.family = is_ipv6(ip) ? AF_INET6 : AF_INET,
+		.sotype = sotype,
+		.reuseport = reuseport_prog,
+	};
+	struct network_helper_opts opts = {
+		.backlog	= SOMAXCONN,
+		.post_socket_cb = setsockopts,
+		.cb_opts	= &cb_opts,
+	};
+	int err, fd;
+
+	fd = start_server_str(cb_opts.family, sotype, ip, port, &opts);
+	if (!ASSERT_OK_FD(fd, "start_server_str"))
+		return -1;
 
 	/* Late attach reuseport prog so we can have one init path */
 	if (reuseport_prog) {
@@ -406,18 +416,12 @@ static int udp_recv_send(int server_fd)
 	}
 
 	/* Reply from original destination address. */
-	fd = socket(dst_addr->ss_family, SOCK_DGRAM, 0);
-	if (CHECK(fd < 0, "socket", "failed\n")) {
+	fd = start_server_addr(SOCK_DGRAM, dst_addr, sizeof(*dst_addr), NULL);
+	if (!ASSERT_OK_FD(fd, "start_server_addr")) {
 		log_err("failed to create tx socket");
 		return -1;
 	}
 
-	ret = bind(fd, (struct sockaddr *)dst_addr, sizeof(*dst_addr));
-	if (CHECK(ret, "bind", "failed\n")) {
-		log_err("failed to bind tx socket");
-		goto out;
-	}
-
 	msg.msg_control = NULL;
 	msg.msg_controllen = 0;
 	n = sendmsg(fd, &msg, 0);
@@ -629,9 +633,6 @@ static void run_lookup_prog(const struct test *t)
 	 * BPF socket lookup.
 	 */
 	if (t->reuseport_has_conns) {
-		struct sockaddr_storage addr = {};
-		socklen_t len = sizeof(addr);
-
 		/* Add an extra socket to reuseport group */
 		reuse_conn_fd = make_server(t->sotype, t->listen_at.ip,
 					    t->listen_at.port,
@@ -640,11 +641,8 @@ static void run_lookup_prog(const struct test *t)
 			goto close;
 
 		 /* Connect the extra socket to itself */
-		err = getsockname(reuse_conn_fd, (void *)&addr, &len);
-		if (CHECK(err, "getsockname", "errno %d\n", errno))
-			goto close;
-		err = connect(reuse_conn_fd, (void *)&addr, len);
-		if (CHECK(err, "connect", "errno %d\n", errno))
+		err = connect_fd_to_fd(reuse_conn_fd, reuse_conn_fd, 0);
+		if (!ASSERT_OK(err, "connect_fd_to_fd"))
 			goto close;
 	}
 
@@ -994,7 +992,7 @@ static void drop_on_reuseport(const struct test *t)
 
 	err = update_lookup_map(t->sock_map, SERVER_A, server1);
 	if (err)
-		goto detach;
+		goto close_srv1;
 
 	/* second server on destination address we should never reach */
 	server2 = make_server(t->sotype, t->connect_to.ip, t->connect_to.port,

tools/testing/selftests/bpf/test_progs.h

@@ -377,6 +377,15 @@ int test__join_cgroup(const char *path);
 	___ok;								\
 })
 
+#define ASSERT_OK_FD(fd, name) ({					\
+	static int duration = 0;					\
+	int ___fd = (fd);						\
+	bool ___ok = ___fd >= 0;					\
+	CHECK(!___ok, (name), "unexpected fd: %d (errno %d)\n",		\
+	      ___fd, errno);						\
+	___ok;								\
+})
+
 #define SYS(goto_label, fmt, ...)					\
 	({								\
 		char cmd[1024];						\