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, 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 }