LXR linux/samples/bpf/sockex2

   1// SPDX-License-Identifier: GPL-2.0
   2#include <stdio.h>
   3#include <assert.h>
   4#include <linux/bpf.h>
   5#include <bpf/bpf.h>
   6#include <bpf/libbpf.h>
   7#include "sock_example.h"
   8#include <unistd.h>
   9#include <arpa/inet.h>
  10#include <sys/resource.h>
  11
  12struct pair {
  13        __u64 packets;
  14        __u64 bytes;
  15};
  16
  17int main(int ac, char **argv)
  18{
  19        struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
  20        struct bpf_object *obj;
  21        int map_fd, prog_fd;
  22        char filename[256];
  23        int i, sock;
  24        FILE *f;
  25
  26        snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
  27        setrlimit(RLIMIT_MEMLOCK, &r);
  28
  29        if (bpf_prog_load(filename, BPF_PROG_TYPE_SOCKET_FILTER,
  30                          &obj, &prog_fd))
  31                return 1;
  32
  33        map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
  34
  35        sock = open_raw_sock("lo");
  36
  37        assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd,
  38                          sizeof(prog_fd)) == 0);
  39
  40        f = popen("ping -4 -c5 localhost", "r");
  41        (void) f;
  42
  43        for (i = 0; i < 5; i++) {
  44                int key = 0, next_key;
  45                struct pair value;
  46
  47                while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) {
  48                        bpf_map_lookup_elem(map_fd, &next_key, &value);
  49                        printf("ip %s bytes %lld packets %lld\n",
  50                               inet_ntoa((struct in_addr){htonl(next_key)}),
  51                               value.bytes, value.packets);
  52                        key = next_key;
  53                }
  54                sleep(1);
  55        }
  56        return 0;
  57}
  58