tools/testing/selftests/bpf/connect4_prog.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (c) 2018 Facebook
   3
   4 #include <string.h>
   5
   6 #include <linux/stddef.h>
   7 #include <linux/bpf.h>
   8 #include <linux/in.h>
   9 #include <linux/in6.h>
  10 #include <sys/socket.h>
  11
  12 #include "bpf_helpers.h"
  13 #include "bpf_endian.h"
  14
  15 #define SRC_REWRITE_IP4         0x7f000004U
  16 #define DST_REWRITE_IP4         0x7f000001U
  17 #define DST_REWRITE_PORT4       4444
  18
  19 int _version SEC("version") = 1;
  20
  21 SEC("cgroup/connect4")
  22 int connect_v4_prog(struct bpf_sock_addr *ctx)
  23 {
  24         struct sockaddr_in sa;
  25
  26         /* Rewrite destination. */
  27         ctx->user_ip4 = bpf_htonl(DST_REWRITE_IP4);
  28         ctx->user_port = bpf_htons(DST_REWRITE_PORT4);
  29
  30         if (ctx->type == SOCK_DGRAM || ctx->type == SOCK_STREAM) {
  31                 ///* Rewrite source. */
  32                 memset(&sa, 0, sizeof(sa));
  33
  34                 sa.sin_family = AF_INET;
  35                 sa.sin_port = bpf_htons(0);
  36                 sa.sin_addr.s_addr = bpf_htonl(SRC_REWRITE_IP4);
  37
  38                 if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0)
  39                         return 0;
  40         }
  41
  42         return 1;
  43 }
  44
  45 char _license[] SEC("license") = "GPL";