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Note: File does not exist in v3.1.
  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 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
101cleanup:
102	bpf_object__close(obj);
103	return 0;
104}