1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <stdio.h>
3*4882a593Smuzhiyun #include <unistd.h>
4*4882a593Smuzhiyun #include <string.h>
5*4882a593Smuzhiyun #include <assert.h>
6*4882a593Smuzhiyun #include <sys/resource.h>
7*4882a593Smuzhiyun #include <bpf/libbpf.h>
8*4882a593Smuzhiyun #include <bpf/bpf.h>
9*4882a593Smuzhiyun #include "trace_helpers.h"
10*4882a593Smuzhiyun
main(int ac,char ** argv)11*4882a593Smuzhiyun int main(int ac, char **argv)
12*4882a593Smuzhiyun {
13*4882a593Smuzhiyun struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
14*4882a593Smuzhiyun char filename[256], symbol[256];
15*4882a593Smuzhiyun struct bpf_object *obj = NULL;
16*4882a593Smuzhiyun struct bpf_link *links[20];
17*4882a593Smuzhiyun long key, next_key, value;
18*4882a593Smuzhiyun struct bpf_program *prog;
19*4882a593Smuzhiyun int map_fd, i, j = 0;
20*4882a593Smuzhiyun const char *section;
21*4882a593Smuzhiyun struct ksym *sym;
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun if (setrlimit(RLIMIT_MEMLOCK, &r)) {
24*4882a593Smuzhiyun perror("setrlimit(RLIMIT_MEMLOCK)");
25*4882a593Smuzhiyun return 1;
26*4882a593Smuzhiyun }
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun if (load_kallsyms()) {
29*4882a593Smuzhiyun printf("failed to process /proc/kallsyms\n");
30*4882a593Smuzhiyun return 2;
31*4882a593Smuzhiyun }
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
34*4882a593Smuzhiyun obj = bpf_object__open_file(filename, NULL);
35*4882a593Smuzhiyun if (libbpf_get_error(obj)) {
36*4882a593Smuzhiyun fprintf(stderr, "ERROR: opening BPF object file failed\n");
37*4882a593Smuzhiyun obj = NULL;
38*4882a593Smuzhiyun goto cleanup;
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun /* load BPF program */
42*4882a593Smuzhiyun if (bpf_object__load(obj)) {
43*4882a593Smuzhiyun fprintf(stderr, "ERROR: loading BPF object file failed\n");
44*4882a593Smuzhiyun goto cleanup;
45*4882a593Smuzhiyun }
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun map_fd = bpf_object__find_map_fd_by_name(obj, "my_map");
48*4882a593Smuzhiyun if (map_fd < 0) {
49*4882a593Smuzhiyun fprintf(stderr, "ERROR: finding a map in obj file failed\n");
50*4882a593Smuzhiyun goto cleanup;
51*4882a593Smuzhiyun }
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun bpf_object__for_each_program(prog, obj) {
54*4882a593Smuzhiyun section = bpf_program__section_name(prog);
55*4882a593Smuzhiyun if (sscanf(section, "kprobe/%s", symbol) != 1)
56*4882a593Smuzhiyun continue;
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun /* Attach prog only when symbol exists */
59*4882a593Smuzhiyun if (ksym_get_addr(symbol)) {
60*4882a593Smuzhiyun links[j] = bpf_program__attach(prog);
61*4882a593Smuzhiyun if (libbpf_get_error(links[j])) {
62*4882a593Smuzhiyun fprintf(stderr, "bpf_program__attach failed\n");
63*4882a593Smuzhiyun links[j] = NULL;
64*4882a593Smuzhiyun goto cleanup;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun j++;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun for (i = 0; i < 5; i++) {
71*4882a593Smuzhiyun key = 0;
72*4882a593Smuzhiyun printf("kprobing funcs:");
73*4882a593Smuzhiyun while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) {
74*4882a593Smuzhiyun bpf_map_lookup_elem(map_fd, &next_key, &value);
75*4882a593Smuzhiyun assert(next_key == value);
76*4882a593Smuzhiyun sym = ksym_search(value);
77*4882a593Smuzhiyun key = next_key;
78*4882a593Smuzhiyun if (!sym) {
79*4882a593Smuzhiyun printf("ksym not found. Is kallsyms loaded?\n");
80*4882a593Smuzhiyun continue;
81*4882a593Smuzhiyun }
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun printf(" %s", sym->name);
84*4882a593Smuzhiyun }
85*4882a593Smuzhiyun if (key)
86*4882a593Smuzhiyun printf("\n");
87*4882a593Smuzhiyun key = 0;
88*4882a593Smuzhiyun while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0)
89*4882a593Smuzhiyun bpf_map_delete_elem(map_fd, &next_key);
90*4882a593Smuzhiyun sleep(1);
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun cleanup:
94*4882a593Smuzhiyun for (j--; j >= 0; j--)
95*4882a593Smuzhiyun bpf_link__destroy(links[j]);
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun bpf_object__close(obj);
98*4882a593Smuzhiyun return 0;
99*4882a593Smuzhiyun }
100