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 #include <sys/resource.h>
  10
  11 struct 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
  21 struct pair {
  22         __u64 packets;
  23         __u64 bytes;
  24 };
  25
  26 int 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
 101 cleanup:
 102         bpf_object__close(obj);
 103         return 0;
 104 }