xref: /linux/samples/bpf/sockex3_user.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <stdio.h>
3 #include <assert.h>
4 #include <bpf/bpf.h>
5 #include <bpf/libbpf.h>
6 #include "sock_example.h"
7 #include <unistd.h>
8 #include <arpa/inet.h>
9 
10 struct flow_key_record {
11 	__be32 src;
12 	__be32 dst;
13 	union {
14 		__be32 ports;
15 		__be16 port16[2];
16 	};
17 	__u32 ip_proto;
18 };
19 
20 struct pair {
21 	__u64 packets;
22 	__u64 bytes;
23 };
24 
25 int main(int argc, char **argv)
26 {
27 	int i, sock, fd, main_prog_fd, hash_map_fd;
28 	struct bpf_program *prog;
29 	struct bpf_object *obj;
30 	char filename[256];
31 	FILE *f;
32 
33 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
34 
35 	obj = bpf_object__open_file(filename, NULL);
36 	if (libbpf_get_error(obj)) {
37 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
38 		return 0;
39 	}
40 
41 	/* load BPF program */
42 	if (bpf_object__load(obj)) {
43 		fprintf(stderr, "ERROR: loading BPF object file failed\n");
44 		goto cleanup;
45 	}
46 
47 	hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
48 	if (hash_map_fd < 0) {
49 		fprintf(stderr, "ERROR: finding a map in obj file failed\n");
50 		goto cleanup;
51 	}
52 
53 	/* find BPF main program */
54 	main_prog_fd = 0;
55 	bpf_object__for_each_program(prog, obj) {
56 		fd = bpf_program__fd(prog);
57 
58 		if (!strcmp(bpf_program__name(prog), "main_prog"))
59 			main_prog_fd = fd;
60 	}
61 
62 	if (main_prog_fd == 0) {
63 		fprintf(stderr, "ERROR: can't find main_prog\n");
64 		goto cleanup;
65 	}
66 
67 	sock = open_raw_sock("lo");
68 
69 	/* attach BPF program to socket */
70 	assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &main_prog_fd,
71 			  sizeof(__u32)) == 0);
72 
73 	if (argc > 1)
74 		f = popen("ping -4 -c5 localhost", "r");
75 	else
76 		f = popen("netperf -l 4 localhost", "r");
77 	(void) f;
78 
79 	for (i = 0; i < 5; i++) {
80 		struct flow_key_record key = {}, next_key;
81 		struct pair value;
82 
83 		sleep(1);
84 		printf("IP     src.port -> dst.port               bytes      packets\n");
85 		while (bpf_map_get_next_key(hash_map_fd, &key, &next_key) == 0) {
86 			bpf_map_lookup_elem(hash_map_fd, &next_key, &value);
87 			printf("%s.%05d -> %s.%05d %12lld %12lld\n",
88 			       inet_ntoa((struct in_addr){htonl(next_key.src)}),
89 			       next_key.port16[0],
90 			       inet_ntoa((struct in_addr){htonl(next_key.dst)}),
91 			       next_key.port16[1],
92 			       value.bytes, value.packets);
93 			key = next_key;
94 		}
95 	}
96 
97 cleanup:
98 	bpf_object__close(obj);
99 	return 0;
100 }
101