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 rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
  30         struct bpf_program *prog;
  31         struct bpf_object *obj;
  32         const char *section;
  33         char filename[256];
  34         FILE *f;
  35
  36         snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
  37         setrlimit(RLIMIT_MEMLOCK, &r);
  38
  39         obj = bpf_object__open_file(filename, NULL);
  40         if (libbpf_get_error(obj)) {
  41                 fprintf(stderr, "ERROR: opening BPF object file failed\n");
  42                 return 0;
  43         }
  44
  45         /* load BPF program */
  46         if (bpf_object__load(obj)) {
  47                 fprintf(stderr, "ERROR: loading BPF object file failed\n");
  48                 goto cleanup;
  49         }
  50
  51         jmp_table_fd = bpf_object__find_map_fd_by_name(obj, "jmp_table");
  52         hash_map_fd = bpf_object__find_map_fd_by_name(obj, "hash_map");
  53         if (jmp_table_fd < 0 || hash_map_fd < 0) {
  54                 fprintf(stderr, "ERROR: finding a map in obj file failed\n");
  55                 goto cleanup;
  56         }
  57
  58         bpf_object__for_each_program(prog, obj) {
  59                 fd = bpf_program__fd(prog);
  60
  61                 section = bpf_program__section_name(prog);
  62                 if (sscanf(section, "socket/%d", &key) != 1) {
  63                         fprintf(stderr, "ERROR: finding prog failed\n");
  64                         goto cleanup;
  65                 }
  66
  67                 if (key == 0)
  68                         main_prog_fd = fd;
  69                 else
  70                         bpf_map_update_elem(jmp_table_fd, &key, &fd, BPF_ANY);
  71         }
  72
  73         sock = open_raw_sock("lo");
  74
  75         /* attach BPF program to socket */
  76         assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &main_prog_fd,
  77                           sizeof(__u32)) == 0);
  78
  79         if (argc > 1)
  80                 f = popen("ping -4 -c5 localhost", "r");
  81         else
  82                 f = popen("netperf -l 4 localhost", "r");
  83         (void) f;
  84
  85         for (i = 0; i < 5; i++) {
  86                 struct flow_key_record key = {}, next_key;
  87                 struct pair value;
  88
  89                 sleep(1);
  90                 printf("IP     src.port -> dst.port               bytes      packets\n");
  91                 while (bpf_map_get_next_key(hash_map_fd, &key, &next_key) == 0) {
  92                         bpf_map_lookup_elem(hash_map_fd, &next_key, &value);
  93                         printf("%s.%05d -> %s.%05d %12lld %12lld\n",
  94                                inet_ntoa((struct in_addr){htonl(next_key.src)}),
  95                                next_key.port16[0],
  96                                inet_ntoa((struct in_addr){htonl(next_key.dst)}),
  97                                next_key.port16[1],
  98                                value.bytes, value.packets);
  99                         key = next_key;
 100                 }
 101         }
 102
 103 cleanup:
 104         bpf_object__close(obj);
 105         return 0;
 106 }