xref: /linux/samples/bpf/sockex3_user.c (revision f7af616c632ee2ac3af0876fe33bf9e0232e665a)
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 #include <sys/resource.h>
10 
11 struct flow_key_record {
12 	__be32 src;
13 	__be32 dst;
14 	union {
15 		__be32 ports;
16 		__be16 port16[2];
17 	};
18 	__u32 ip_proto;
19 };
20 
21 struct pair {
22 	__u64 packets;
23 	__u64 bytes;
24 };
25 
26 int main(int argc, char **argv)
27 {
28 	int i, sock, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd;
29 	struct bpf_program *prog;
30 	struct bpf_object *obj;
31 	const char *section;
32 	char filename[256];
33 	FILE *f;
34 
35 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
36 
37 	obj = bpf_object__open_file(filename, NULL);
38 	if (libbpf_get_error(obj)) {
39 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
40 		return 0;
41 	}
42 
43 	/* load BPF program */
44 	if (bpf_object__load(obj)) {
45 		fprintf(stderr, "ERROR: loading BPF object file failed\n");
46 		goto cleanup;
47 	}
48 
49 	jmp_table_fd = bpf_object__find_map_fd_by_name(obj, "jmp_table");
50 	hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
51 	if (jmp_table_fd < 0 || hash_map_fd < 0) {
52 		fprintf(stderr, "ERROR: finding a map in obj file failed\n");
53 		goto cleanup;
54 	}
55 
56 	bpf_object__for_each_program(prog, obj) {
57 		fd = bpf_program__fd(prog);
58 
59 		section = bpf_program__section_name(prog);
60 		if (sscanf(section, "socket/%d", &key) != 1) {
61 			fprintf(stderr, "ERROR: finding prog failed\n");
62 			goto cleanup;
63 		}
64 
65 		if (key == 0)
66 			main_prog_fd = fd;
67 		else
68 			bpf_map_update_elem(jmp_table_fd, &key, &fd, BPF_ANY);
69 	}
70 
71 	sock = open_raw_sock("lo");
72 
73 	/* attach BPF program to socket */
74 	assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &main_prog_fd,
75 			  sizeof(__u32)) == 0);
76 
77 	if (argc > 1)
78 		f = popen("ping -4 -c5 localhost", "r");
79 	else
80 		f = popen("netperf -l 4 localhost", "r");
81 	(void) f;
82 
83 	for (i = 0; i < 5; i++) {
84 		struct flow_key_record key = {}, next_key;
85 		struct pair value;
86 
87 		sleep(1);
88 		printf("IP     src.port -> dst.port               bytes      packets\n");
89 		while (bpf_map_get_next_key(hash_map_fd, &key, &next_key) == 0) {
90 			bpf_map_lookup_elem(hash_map_fd, &next_key, &value);
91 			printf("%s.%05d -> %s.%05d %12lld %12lld\n",
92 			       inet_ntoa((struct in_addr){htonl(next_key.src)}),
93 			       next_key.port16[0],
94 			       inet_ntoa((struct in_addr){htonl(next_key.dst)}),
95 			       next_key.port16[1],
96 			       value.bytes, value.packets);
97 			key = next_key;
98 		}
99 	}
100 
101 cleanup:
102 	bpf_object__close(obj);
103 	return 0;
104 }
105