samples/bpf/sockex3_user.c

   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, fd, main_prog_fd, hash_map_fd;
  28         struct bpf_program *prog;
  29         struct bpf_object *obj;
  30         char filename[256];
  31         FILE *f;
  32
  33         snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
  34
  35         obj = bpf_object__open_file(filename, NULL);
  36         if (libbpf_get_error(obj)) {
  37                 fprintf(stderr, "ERROR: opening BPF object file failed\n");
  38                 return 0;
  39         }
  40
  41         /* load BPF program */
  42         if (bpf_object__load(obj)) {
  43                 fprintf(stderr, "ERROR: loading BPF object file failed\n");
  44                 goto cleanup;
  45         }
  46
  47         hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
  48         if (hash_map_fd < 0) {
  49                 fprintf(stderr, "ERROR: finding a map in obj file failed\n");
  50                 goto cleanup;
  51         }
  52
  53         /* find BPF main program */
  54         main_prog_fd = 0;
  55         bpf_object__for_each_program(prog, obj) {
  56                 fd = bpf_program__fd(prog);
  57
  58                 if (!strcmp(bpf_program__name(prog), "main_prog"))
  59                         main_prog_fd = fd;
  60         }
  61
  62         if (main_prog_fd == 0) {
  63                 fprintf(stderr, "ERROR: can't find main_prog\n");
  64                 goto cleanup;
  65         }
  66
  67         sock = open_raw_sock("lo");
  68
  69         /* attach BPF program to socket */
  70         assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &main_prog_fd,
  71                           sizeof(__u32)) == 0);
  72
  73         if (argc > 1)
  74                 f = popen("ping -4 -c5 localhost", "r");
  75         else
  76                 f = popen("netperf -l 4 localhost", "r");
  77         (void) f;
  78
  79         for (i = 0; i < 5; i++) {
  80                 struct flow_key_record key = {}, next_key;
  81                 struct pair value;
  82
  83                 sleep(1);
  84                 printf("IP     src.port -> dst.port               bytes      packets\n");
  85                 while (bpf_map_get_next_key(hash_map_fd, &key, &next_key) == 0) {
  86                         bpf_map_lookup_elem(hash_map_fd, &next_key, &value);
  87                         printf("%s.%05d -> %s.%05d %12lld %12lld\n",
  88                                inet_ntoa((struct in_addr){htonl(next_key.src)}),
  89                                next_key.port16[0],
  90                                inet_ntoa((struct in_addr){htonl(next_key.dst)}),
  91                                next_key.port16[1],
  92                                value.bytes, value.packets);
  93                         key = next_key;
  94                 }
  95         }
  96
  97 cleanup:
  98         bpf_object__close(obj);
  99         return 0;
 100 }