tools/testing/selftests/bpf/prog_tests/skb_ctx.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <test_progs.h>
   3 #include <network_helpers.h>
   4
   5 void test_skb_ctx(void)
   6 {
   7         struct __sk_buff skb = {
   8                 .cb[0] = 1,
   9                 .cb[1] = 2,
  10                 .cb[2] = 3,
  11                 .cb[3] = 4,
  12                 .cb[4] = 5,
  13                 .priority = 6,
  14                 .ifindex = 1,
  15                 .tstamp = 7,
  16                 .wire_len = 100,
  17                 .gso_segs = 8,
  18                 .mark = 9,
  19                 .gso_size = 10,
  20         };
  21         struct bpf_prog_test_run_attr tattr = {
  22                 .data_in = &pkt_v4,
  23                 .data_size_in = sizeof(pkt_v4),
  24                 .ctx_in = &skb,
  25                 .ctx_size_in = sizeof(skb),
  26                 .ctx_out = &skb,
  27                 .ctx_size_out = sizeof(skb),
  28         };
  29         struct bpf_object *obj;
  30         int err;
  31         int i;
  32
  33         err = bpf_prog_load("./test_skb_ctx.o", BPF_PROG_TYPE_SCHED_CLS, &obj,
  34                             &tattr.prog_fd);
  35         if (CHECK_ATTR(err, "load", "err %d errno %d\n", err, errno))
  36                 return;
  37
  38         /* ctx_in != NULL, ctx_size_in == 0 */
  39
  40         tattr.ctx_size_in = 0;
  41         err = bpf_prog_test_run_xattr(&tattr);
  42         CHECK_ATTR(err == 0, "ctx_size_in", "err %d errno %d\n", err, errno);
  43         tattr.ctx_size_in = sizeof(skb);
  44
  45         /* ctx_out != NULL, ctx_size_out == 0 */
  46
  47         tattr.ctx_size_out = 0;
  48         err = bpf_prog_test_run_xattr(&tattr);
  49         CHECK_ATTR(err == 0, "ctx_size_out", "err %d errno %d\n", err, errno);
  50         tattr.ctx_size_out = sizeof(skb);
  51
  52         /* non-zero [len, tc_index] fields should be rejected*/
  53
  54         skb.len = 1;
  55         err = bpf_prog_test_run_xattr(&tattr);
  56         CHECK_ATTR(err == 0, "len", "err %d errno %d\n", err, errno);
  57         skb.len = 0;
  58
  59         skb.tc_index = 1;
  60         err = bpf_prog_test_run_xattr(&tattr);
  61         CHECK_ATTR(err == 0, "tc_index", "err %d errno %d\n", err, errno);
  62         skb.tc_index = 0;
  63
  64         /* non-zero [hash, sk] fields should be rejected */
  65
  66         skb.hash = 1;
  67         err = bpf_prog_test_run_xattr(&tattr);
  68         CHECK_ATTR(err == 0, "hash", "err %d errno %d\n", err, errno);
  69         skb.hash = 0;
  70
  71         skb.sk = (struct bpf_sock *)1;
  72         err = bpf_prog_test_run_xattr(&tattr);
  73         CHECK_ATTR(err == 0, "sk", "err %d errno %d\n", err, errno);
  74         skb.sk = 0;
  75
  76         err = bpf_prog_test_run_xattr(&tattr);
  77         CHECK_ATTR(err != 0 || tattr.retval,
  78                    "run",
  79                    "err %d errno %d retval %d\n",
  80                    err, errno, tattr.retval);
  81
  82         CHECK_ATTR(tattr.ctx_size_out != sizeof(skb),
  83                    "ctx_size_out",
  84                    "incorrect output size, want %zu have %u\n",
  85                    sizeof(skb), tattr.ctx_size_out);
  86
  87         for (i = 0; i < 5; i++)
  88                 CHECK_ATTR(skb.cb[i] != i + 2,
  89                            "ctx_out_cb",
  90                            "skb->cb[i] == %d, expected %d\n",
  91                            skb.cb[i], i + 2);
  92         CHECK_ATTR(skb.priority != 7,
  93                    "ctx_out_priority",
  94                    "skb->priority == %d, expected %d\n",
  95                    skb.priority, 7);
  96         CHECK_ATTR(skb.ifindex != 1,
  97                    "ctx_out_ifindex",
  98                    "skb->ifindex == %d, expected %d\n",
  99                    skb.ifindex, 1);
 100         CHECK_ATTR(skb.tstamp != 8,
 101                    "ctx_out_tstamp",
 102                    "skb->tstamp == %lld, expected %d\n",
 103                    skb.tstamp, 8);
 104         CHECK_ATTR(skb.mark != 10,
 105                    "ctx_out_mark",
 106                    "skb->mark == %u, expected %d\n",
 107                    skb.mark, 10);
 108 }