1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2023 Hengqi Chen */
3
4#include <test_progs.h>
5#include "test_uprobe.skel.h"
6
7static FILE *urand_spawn(int *pid)
8{
9	FILE *f;
10
11	/* urandom_read's stdout is wired into f */
12	f = popen("./urandom_read 1 report-pid", "r");
13	if (!f)
14		return NULL;
15
16	if (fscanf(f, "%d", pid) != 1) {
17		pclose(f);
18		errno = EINVAL;
19		return NULL;
20	}
21
22	return f;
23}
24
25static int urand_trigger(FILE **urand_pipe)
26{
27	int exit_code;
28
29	/* pclose() waits for child process to exit and returns their exit code */
30	exit_code = pclose(*urand_pipe);
31	*urand_pipe = NULL;
32
33	return exit_code;
34}
35
36void test_uprobe(void)
37{
38	LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts);
39	struct test_uprobe *skel;
40	FILE *urand_pipe = NULL;
41	int urand_pid = 0, err;
42
43	skel = test_uprobe__open_and_load();
44	if (!ASSERT_OK_PTR(skel, "skel_open"))
45		return;
46
47	urand_pipe = urand_spawn(&urand_pid);
48	if (!ASSERT_OK_PTR(urand_pipe, "urand_spawn"))
49		goto cleanup;
50
51	skel->bss->my_pid = urand_pid;
52
53	/* Manual attach uprobe to urandlib_api
54	 * There are two `urandlib_api` symbols in .dynsym section:
55	 *   - urandlib_api@LIBURANDOM_READ_1.0.0
56	 *   - urandlib_api@@LIBURANDOM_READ_2.0.0
57	 * Both are global bind and would cause a conflict if user
58	 * specify the symbol name without a version suffix
59	 */
60	uprobe_opts.func_name = "urandlib_api";
61	skel->links.test4 = bpf_program__attach_uprobe_opts(skel->progs.test4,
62							    urand_pid,
63							    "./liburandom_read.so",
64							    0 /* offset */,
65							    &uprobe_opts);
66	if (!ASSERT_ERR_PTR(skel->links.test4, "urandlib_api_attach_conflict"))
67		goto cleanup;
68
69	uprobe_opts.func_name = "urandlib_api@LIBURANDOM_READ_1.0.0";
70	skel->links.test4 = bpf_program__attach_uprobe_opts(skel->progs.test4,
71							    urand_pid,
72							    "./liburandom_read.so",
73							    0 /* offset */,
74							    &uprobe_opts);
75	if (!ASSERT_OK_PTR(skel->links.test4, "urandlib_api_attach_ok"))
76		goto cleanup;
77
78	/* Auto attach 3 u[ret]probes to urandlib_api_sameoffset */
79	err = test_uprobe__attach(skel);
80	if (!ASSERT_OK(err, "skel_attach"))
81		goto cleanup;
82
83	/* trigger urandom_read */
84	ASSERT_OK(urand_trigger(&urand_pipe), "urand_exit_code");
85
86	ASSERT_EQ(skel->bss->test1_result, 1, "urandlib_api_sameoffset");
87	ASSERT_EQ(skel->bss->test2_result, 1, "urandlib_api_sameoffset@v1");
88	ASSERT_EQ(skel->bss->test3_result, 3, "urandlib_api_sameoffset@@v2");
89	ASSERT_EQ(skel->bss->test4_result, 1, "urandlib_api");
90
91cleanup:
92	if (urand_pipe)
93		pclose(urand_pipe);
94	test_uprobe__destroy(skel);
95}
96