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
11struct 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
21struct pair {
22	__u64 packets;
23	__u64 bytes;
24};
25
26int main(int argc, char **argv)
27{
28	int i, sock, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd;
29	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
30	struct bpf_program *prog;
31	struct bpf_object *obj;
32	const char *section;
33	char filename[256];
34	FILE *f;
35
36	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
37	setrlimit(RLIMIT_MEMLOCK, &r);
38
39	obj = bpf_object__open_file(filename, NULL);
40	if (libbpf_get_error(obj)) {
41		fprintf(stderr, "ERROR: opening BPF object file failed\n");
42		return 0;
43	}
44
45	/* load BPF program */
46	if (bpf_object__load(obj)) {
47		fprintf(stderr, "ERROR: loading BPF object file failed\n");
48		goto cleanup;
49	}
50
51	jmp_table_fd = bpf_object__find_map_fd_by_name(obj, "jmp_table");
52	hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
53	if (jmp_table_fd < 0 || hash_map_fd < 0) {
54		fprintf(stderr, "ERROR: finding a map in obj file failed\n");
55		goto cleanup;
56	}
57
58	bpf_object__for_each_program(prog, obj) {
59		fd = bpf_program__fd(prog);
60
61		section = bpf_program__section_name(prog);
62		if (sscanf(section, "socket/%d", &key) != 1) {
63			fprintf(stderr, "ERROR: finding prog failed\n");
64			goto cleanup;
65		}
66
67		if (key == 0)
68			main_prog_fd = fd;
69		else
70			bpf_map_update_elem(jmp_table_fd, &key, &fd, BPF_ANY);
71	}
72
73	sock = open_raw_sock("lo");
74
75	/* attach BPF program to socket */
76	assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &main_prog_fd,
77			  sizeof(__u32)) == 0);
78
79	if (argc > 1)
80		f = popen("ping -4 -c5 localhost", "r");
81	else
82		f = popen("netperf -l 4 localhost", "r");
83	(void) f;
84
85	for (i = 0; i < 5; i++) {
86		struct flow_key_record key = {}, next_key;
87		struct pair value;
88
89		sleep(1);
90		printf("IP     src.port -> dst.port               bytes      packets\n");
91		while (bpf_map_get_next_key(hash_map_fd, &key, &next_key) == 0) {
92			bpf_map_lookup_elem(hash_map_fd, &next_key, &value);
93			printf("%s.%05d -> %s.%05d %12lld %12lld\n",
94			       inet_ntoa((struct in_addr){htonl(next_key.src)}),
95			       next_key.port16[0],
96			       inet_ntoa((struct in_addr){htonl(next_key.dst)}),
97			       next_key.port16[1],
98			       value.bytes, value.packets);
99			key = next_key;
100		}
101	}
102
103cleanup:
104	bpf_object__close(obj);
105	return 0;
106}
107