1 files changed, 309 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/sk_assign.c b/tools/testing/selftests/bpf/prog_tests/sk_assign.c
new file mode 100644
index 000000000000..d572e1a2c297
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/sk_assign.c
@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Facebook
+// Copyright (c) 2019 Cloudflare
+// Copyright (c) 2020 Isovalent, Inc.
+/*
+ * Test that the socket assign program is able to redirect traffic towards a
+ * socket, regardless of whether the port or address destination of the traffic
+ * matches the port.
+ */
+
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "test_progs.h"
+
+#define BIND_PORT 1234
+#define CONNECT_PORT 4321
+#define TEST_DADDR (0xC0A80203)
+#define NS_SELF "/proc/self/ns/net"
+
+static const struct timeval timeo_sec = { .tv_sec = 3 };
+static const size_t timeo_optlen = sizeof(timeo_sec);
+static int stop, duration;
+
+static bool
+configure_stack(void)
+{
+	char tc_cmd[BUFSIZ];
+
+	/* Move to a new networking namespace */
+	if (CHECK_FAIL(unshare(CLONE_NEWNET)))
+		return false;
+
+	/* Configure necessary links, routes */
+	if (CHECK_FAIL(system("ip link set dev lo up")))
+		return false;
+	if (CHECK_FAIL(system("ip route add local default dev lo")))
+		return false;
+	if (CHECK_FAIL(system("ip -6 route add local default dev lo")))
+		return false;
+
+	/* Load qdisc, BPF program */
+	if (CHECK_FAIL(system("tc qdisc add dev lo clsact")))
+		return false;
+	sprintf(tc_cmd, "%s %s %s %s", "tc filter add dev lo ingress bpf",
+		       "direct-action object-file ./test_sk_assign.o",
+		       "section classifier/sk_assign_test",
+		       (env.verbosity < VERBOSE_VERY) ? " 2>/dev/null" : "");
+	if (CHECK(system(tc_cmd), "BPF load failed;",
+		  "run with -vv for more info\n"))
+		return false;
+
+	return true;
+}
+
+static int
+start_server(const struct sockaddr *addr, socklen_t len, int type)
+{
+	int fd;
+
+	fd = socket(addr->sa_family, type, 0);
+	if (CHECK_FAIL(fd == -1))
+		goto out;
+	if (CHECK_FAIL(setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeo_sec,
+				  timeo_optlen)))
+		goto close_out;
+	if (CHECK_FAIL(bind(fd, addr, len) == -1))
+		goto close_out;
+	if (type == SOCK_STREAM && CHECK_FAIL(listen(fd, 128) == -1))
+		goto close_out;
+
+	goto out;
+close_out:
+	close(fd);
+	fd = -1;
+out:
+	return fd;
+}
+
+static int
+connect_to_server(const struct sockaddr *addr, socklen_t len, int type)
+{
+	int fd = -1;
+
+	fd = socket(addr->sa_family, type, 0);
+	if (CHECK_FAIL(fd == -1))
+		goto out;
+	if (CHECK_FAIL(setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeo_sec,
+				  timeo_optlen)))
+		goto close_out;
+	if (CHECK_FAIL(connect(fd, addr, len)))
+		goto close_out;
+
+	goto out;
+close_out:
+	close(fd);
+	fd = -1;
+out:
+	return fd;
+}
+
+static in_port_t
+get_port(int fd)
+{
+	struct sockaddr_storage ss;
+	socklen_t slen = sizeof(ss);
+	in_port_t port = 0;
+
+	if (CHECK_FAIL(getsockname(fd, (struct sockaddr *)&ss, &slen)))
+		return port;
+
+	switch (ss.ss_family) {
+	case AF_INET:
+		port = ((struct sockaddr_in *)&ss)->sin_port;
+		break;
+	case AF_INET6:
+		port = ((struct sockaddr_in6 *)&ss)->sin6_port;
+		break;
+	default:
+		CHECK(1, "Invalid address family", "%d\n", ss.ss_family);
+	}
+	return port;
+}
+
+static ssize_t
+rcv_msg(int srv_client, int type)
+{
+	struct sockaddr_storage ss;
+	char buf[BUFSIZ];
+	socklen_t slen;
+
+	if (type == SOCK_STREAM)
+		return read(srv_client, &buf, sizeof(buf));
+	else
+		return recvfrom(srv_client, &buf, sizeof(buf), 0,
+				(struct sockaddr *)&ss, &slen);
+}
+
+static int
+run_test(int server_fd, const struct sockaddr *addr, socklen_t len, int type)
+{
+	int client = -1, srv_client = -1;
+	char buf[] = "testing";
+	in_port_t port;
+	int ret = 1;
+
+	client = connect_to_server(addr, len, type);
+	if (client == -1) {
+		perror("Cannot connect to server");
+		goto out;
+	}
+
+	if (type == SOCK_STREAM) {
+		srv_client = accept(server_fd, NULL, NULL);
+		if (CHECK_FAIL(srv_client == -1)) {
+			perror("Can't accept connection");
+			goto out;
+		}
+	} else {
+		srv_client = server_fd;
+	}
+	if (CHECK_FAIL(write(client, buf, sizeof(buf)) != sizeof(buf))) {
+		perror("Can't write on client");
+		goto out;
+	}
+	if (CHECK_FAIL(rcv_msg(srv_client, type) != sizeof(buf))) {
+		perror("Can't read on server");
+		goto out;
+	}
+
+	port = get_port(srv_client);
+	if (CHECK_FAIL(!port))
+		goto out;
+	/* SOCK_STREAM is connected via accept(), so the server's local address
+	 * will be the CONNECT_PORT rather than the BIND port that corresponds
+	 * to the listen socket. SOCK_DGRAM on the other hand is connectionless
+	 * so we can't really do the same check there; the server doesn't ever
+	 * create a socket with CONNECT_PORT.
+	 */
+	if (type == SOCK_STREAM &&
+	    CHECK(port != htons(CONNECT_PORT), "Expected", "port %u but got %u",
+		  CONNECT_PORT, ntohs(port)))
+		goto out;
+	else if (type == SOCK_DGRAM &&
+		 CHECK(port != htons(BIND_PORT), "Expected",
+		       "port %u but got %u", BIND_PORT, ntohs(port)))
+		goto out;
+
+	ret = 0;
+out:
+	close(client);
+	if (srv_client != server_fd)
+		close(srv_client);
+	if (ret)
+		WRITE_ONCE(stop, 1);
+	return ret;
+}
+
+static void
+prepare_addr(struct sockaddr *addr, int family, __u16 port, bool rewrite_addr)
+{
+	struct sockaddr_in *addr4;
+	struct sockaddr_in6 *addr6;
+
+	switch (family) {
+	case AF_INET:
+		addr4 = (struct sockaddr_in *)addr;
+		memset(addr4, 0, sizeof(*addr4));
+		addr4->sin_family = family;
+		addr4->sin_port = htons(port);
+		if (rewrite_addr)
+			addr4->sin_addr.s_addr = htonl(TEST_DADDR);
+		else
+			addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+		break;
+	case AF_INET6:
+		addr6 = (struct sockaddr_in6 *)addr;
+		memset(addr6, 0, sizeof(*addr6));
+		addr6->sin6_family = family;
+		addr6->sin6_port = htons(port);
+		addr6->sin6_addr = in6addr_loopback;
+		if (rewrite_addr)
+			addr6->sin6_addr.s6_addr32[3] = htonl(TEST_DADDR);
+		break;
+	default:
+		fprintf(stderr, "Invalid family %d", family);
+	}
+}
+
+struct test_sk_cfg {
+	const char *name;
+	int family;
+	struct sockaddr *addr;
+	socklen_t len;
+	int type;
+	bool rewrite_addr;
+};
+
+#define TEST(NAME, FAMILY, TYPE, REWRITE)				\
+{									\
+	.name = NAME,							\
+	.family = FAMILY,						\
+	.addr = (FAMILY == AF_INET) ? (struct sockaddr *)&addr4		\
+				    : (struct sockaddr *)&addr6,	\
+	.len = (FAMILY == AF_INET) ? sizeof(addr4) : sizeof(addr6),	\
+	.type = TYPE,							\
+	.rewrite_addr = REWRITE,					\
+}
+
+void test_sk_assign(void)
+{
+	struct sockaddr_in addr4;
+	struct sockaddr_in6 addr6;
+	struct test_sk_cfg tests[] = {
+		TEST("ipv4 tcp port redir", AF_INET, SOCK_STREAM, false),
+		TEST("ipv4 tcp addr redir", AF_INET, SOCK_STREAM, true),
+		TEST("ipv6 tcp port redir", AF_INET6, SOCK_STREAM, false),
+		TEST("ipv6 tcp addr redir", AF_INET6, SOCK_STREAM, true),
+		TEST("ipv4 udp port redir", AF_INET, SOCK_DGRAM, false),
+		TEST("ipv4 udp addr redir", AF_INET, SOCK_DGRAM, true),
+		TEST("ipv6 udp port redir", AF_INET6, SOCK_DGRAM, false),
+		TEST("ipv6 udp addr redir", AF_INET6, SOCK_DGRAM, true),
+	};
+	int server = -1;
+	int self_net;
+
+	self_net = open(NS_SELF, O_RDONLY);
+	if (CHECK_FAIL(self_net < 0)) {
+		perror("Unable to open "NS_SELF);
+		return;
+	}
+
+	if (!configure_stack()) {
+		perror("configure_stack");
+		goto cleanup;
+	}
+
+	for (int i = 0; i < ARRAY_SIZE(tests) && !READ_ONCE(stop); i++) {
+		struct test_sk_cfg *test = &tests[i];
+		const struct sockaddr *addr;
+
+		if (!test__start_subtest(test->name))
+			continue;
+		prepare_addr(test->addr, test->family, BIND_PORT, false);
+		addr = (const struct sockaddr *)test->addr;
+		server = start_server(addr, test->len, test->type);
+		if (server == -1)
+			goto cleanup;
+
+		/* connect to unbound ports */
+		prepare_addr(test->addr, test->family, CONNECT_PORT,
+			     test->rewrite_addr);
+		if (run_test(server, addr, test->len, test->type))
+			goto close;
+
+		close(server);
+		server = -1;
+	}
+
+close:
+	close(server);
+cleanup:
+	if (CHECK_FAIL(setns(self_net, CLONE_NEWNET)))
+		perror("Failed to setns("NS_SELF")");
+	close(self_net);
+}