xref: /linux/tools/testing/selftests/bpf/prog_tests/udp_limit.c (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 #include "udp_limit.skel.h"
4 
5 #include <sys/types.h>
6 #include <sys/socket.h>
7 
8 void test_udp_limit(void)
9 {
10 	struct udp_limit *skel;
11 	int fd1 = -1, fd2 = -1;
12 	int cgroup_fd;
13 
14 	cgroup_fd = test__join_cgroup("/udp_limit");
15 	if (!ASSERT_GE(cgroup_fd, 0, "cg-join"))
16 		return;
17 
18 	skel = udp_limit__open_and_load();
19 	if (!ASSERT_OK_PTR(skel, "skel-load"))
20 		goto close_cgroup_fd;
21 
22 	skel->links.sock = bpf_program__attach_cgroup(skel->progs.sock, cgroup_fd);
23 	if (!ASSERT_OK_PTR(skel->links.sock, "cg_attach_sock"))
24 		goto close_skeleton;
25 	skel->links.sock_release = bpf_program__attach_cgroup(skel->progs.sock_release, cgroup_fd);
26 	if (!ASSERT_OK_PTR(skel->links.sock_release, "cg_attach_sock_release"))
27 		goto close_skeleton;
28 
29 	/* BPF program enforces a single UDP socket per cgroup,
30 	 * verify that.
31 	 */
32 	fd1 = socket(AF_INET, SOCK_DGRAM, 0);
33 	if (!ASSERT_GE(fd1, 0, "socket(fd1)"))
34 		goto close_skeleton;
35 
36 	fd2 = socket(AF_INET, SOCK_DGRAM, 0);
37 	if (!ASSERT_LT(fd2, 0, "socket(fd2)"))
38 		goto close_skeleton;
39 
40 	/* We can reopen again after close. */
41 	close(fd1);
42 	fd1 = -1;
43 
44 	fd1 = socket(AF_INET, SOCK_DGRAM, 0);
45 	if (!ASSERT_GE(fd1, 0, "socket(fd1-again)"))
46 		goto close_skeleton;
47 
48 	/* Make sure the program was invoked the expected
49 	 * number of times:
50 	 * - open fd1           - BPF_CGROUP_INET_SOCK_CREATE
51 	 * - attempt to openfd2 - BPF_CGROUP_INET_SOCK_CREATE
52 	 * - close fd1          - BPF_CGROUP_INET_SOCK_RELEASE
53 	 * - open fd1 again     - BPF_CGROUP_INET_SOCK_CREATE
54 	 */
55 	if (!ASSERT_EQ(skel->bss->invocations, 4, "bss-invocations"))
56 		goto close_skeleton;
57 
58 	/* We should still have a single socket in use */
59 	if (!ASSERT_EQ(skel->bss->in_use, 1, "bss-in_use"))
60 		goto close_skeleton;
61 
62 close_skeleton:
63 	if (fd1 >= 0)
64 		close(fd1);
65 	if (fd2 >= 0)
66 		close(fd2);
67 	udp_limit__destroy(skel);
68 close_cgroup_fd:
69 	close(cgroup_fd);
70 }
71