xref: /linux/samples/bpf/sockex3_user.c (revision 6562c9acb43ac69ba5a956b0c3911b883d90541f)
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, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd;
28 	struct bpf_program *prog;
29 	struct bpf_object *obj;
30 	const char *section;
31 	char filename[256];
32 	FILE *f;
33 
34 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
35 
36 	obj = bpf_object__open_file(filename, NULL);
37 	if (libbpf_get_error(obj)) {
38 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
39 		return 0;
40 	}
41 
42 	/* load BPF program */
43 	if (bpf_object__load(obj)) {
44 		fprintf(stderr, "ERROR: loading BPF object file failed\n");
45 		goto cleanup;
46 	}
47 
48 	jmp_table_fd = bpf_object__find_map_fd_by_name(obj, "jmp_table");
49 	hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
50 	if (jmp_table_fd < 0 || hash_map_fd < 0) {
51 		fprintf(stderr, "ERROR: finding a map in obj file failed\n");
52 		goto cleanup;
53 	}
54 
55 	bpf_object__for_each_program(prog, obj) {
56 		fd = bpf_program__fd(prog);
57 
58 		section = bpf_program__section_name(prog);
59 		if (sscanf(section, "socket/%d", &key) != 1) {
60 			fprintf(stderr, "ERROR: finding prog failed\n");
61 			goto cleanup;
62 		}
63 
64 		if (key == 0)
65 			main_prog_fd = fd;
66 		else
67 			bpf_map_update_elem(jmp_table_fd, &key, &fd, BPF_ANY);
68 	}
69 
70 	sock = open_raw_sock("lo");
71 
72 	/* attach BPF program to socket */
73 	assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &main_prog_fd,
74 			  sizeof(__u32)) == 0);
75 
76 	if (argc > 1)
77 		f = popen("ping -4 -c5 localhost", "r");
78 	else
79 		f = popen("netperf -l 4 localhost", "r");
80 	(void) f;
81 
82 	for (i = 0; i < 5; i++) {
83 		struct flow_key_record key = {}, next_key;
84 		struct pair value;
85 
86 		sleep(1);
87 		printf("IP     src.port -> dst.port               bytes      packets\n");
88 		while (bpf_map_get_next_key(hash_map_fd, &key, &next_key) == 0) {
89 			bpf_map_lookup_elem(hash_map_fd, &next_key, &value);
90 			printf("%s.%05d -> %s.%05d %12lld %12lld\n",
91 			       inet_ntoa((struct in_addr){htonl(next_key.src)}),
92 			       next_key.port16[0],
93 			       inet_ntoa((struct in_addr){htonl(next_key.dst)}),
94 			       next_key.port16[1],
95 			       value.bytes, value.packets);
96 			key = next_key;
97 		}
98 	}
99 
100 cleanup:
101 	bpf_object__close(obj);
102 	return 0;
103 }
104