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

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <test_progs.h>
   3 #include <network_helpers.h>
   4 #include <net/if.h>
   5 #include "empty_skb.skel.h"
   6
   7 void test_empty_skb(void)
   8 {
   9         LIBBPF_OPTS(bpf_test_run_opts, tattr);
  10         struct empty_skb *bpf_obj = NULL;
  11         struct nstoken *tok = NULL;
  12         struct bpf_program *prog;
  13         char eth_hlen_pp[15];
  14         char eth_hlen[14];
  15         int veth_ifindex;
  16         int ipip_ifindex;
  17         int err;
  18         int i;
  19
  20         struct {
  21                 const char *msg;
  22                 const void *data_in;
  23                 __u32 data_size_in;
  24                 int *ifindex;
  25                 int err;
  26                 int ret;
  27                 bool success_on_tc;
  28         } tests[] = {
  29                 /* Empty packets are always rejected. */
  30
  31                 {
  32                         /* BPF_PROG_RUN ETH_HLEN size check */
  33                         .msg = "veth empty ingress packet",
  34                         .data_in = NULL,
  35                         .data_size_in = 0,
  36                         .ifindex = &veth_ifindex,
  37                         .err = -EINVAL,
  38                 },
  39                 {
  40                         /* BPF_PROG_RUN ETH_HLEN size check */
  41                         .msg = "ipip empty ingress packet",
  42                         .data_in = NULL,
  43                         .data_size_in = 0,
  44                         .ifindex = &ipip_ifindex,
  45                         .err = -EINVAL,
  46                 },
  47
  48                 /* ETH_HLEN-sized packets:
  49                  * - can not be redirected at LWT_XMIT
  50                  * - can be redirected at TC to non-tunneling dest
  51                  */
  52
  53                 {
  54                         /* __bpf_redirect_common */
  55                         .msg = "veth ETH_HLEN packet ingress",
  56                         .data_in = eth_hlen,
  57                         .data_size_in = sizeof(eth_hlen),
  58                         .ifindex = &veth_ifindex,
  59                         .ret = -ERANGE,
  60                         .success_on_tc = true,
  61                 },
  62                 {
  63                         /* __bpf_redirect_no_mac
  64                          *
  65                          * lwt: skb->len=0 <= skb_network_offset=0
  66                          * tc: skb->len=14 <= skb_network_offset=14
  67                          */
  68                         .msg = "ipip ETH_HLEN packet ingress",
  69                         .data_in = eth_hlen,
  70                         .data_size_in = sizeof(eth_hlen),
  71                         .ifindex = &ipip_ifindex,
  72                         .ret = -ERANGE,
  73                 },
  74
  75                 /* ETH_HLEN+1-sized packet should be redirected. */
  76
  77                 {
  78                         .msg = "veth ETH_HLEN+1 packet ingress",
  79                         .data_in = eth_hlen_pp,
  80                         .data_size_in = sizeof(eth_hlen_pp),
  81                         .ifindex = &veth_ifindex,
  82                 },
  83                 {
  84                         .msg = "ipip ETH_HLEN+1 packet ingress",
  85                         .data_in = eth_hlen_pp,
  86                         .data_size_in = sizeof(eth_hlen_pp),
  87                         .ifindex = &ipip_ifindex,
  88                 },
  89         };
  90
  91         SYS(out, "ip netns add empty_skb");
  92         tok = open_netns("empty_skb");
  93         SYS(out, "ip link add veth0 type veth peer veth1");
  94         SYS(out, "ip link set dev veth0 up");
  95         SYS(out, "ip link set dev veth1 up");
  96         SYS(out, "ip addr add 10.0.0.1/8 dev veth0");
  97         SYS(out, "ip addr add 10.0.0.2/8 dev veth1");
  98         veth_ifindex = if_nametoindex("veth0");
  99
 100         SYS(out, "ip link add ipip0 type ipip local 10.0.0.1 remote 10.0.0.2");
 101         SYS(out, "ip link set ipip0 up");
 102         SYS(out, "ip addr add 192.168.1.1/16 dev ipip0");
 103         ipip_ifindex = if_nametoindex("ipip0");
 104
 105         bpf_obj = empty_skb__open_and_load();
 106         if (!ASSERT_OK_PTR(bpf_obj, "open skeleton"))
 107                 goto out;
 108
 109         for (i = 0; i < ARRAY_SIZE(tests); i++) {
 110                 bpf_object__for_each_program(prog, bpf_obj->obj) {
 111                         char buf[128];
 112                         bool at_tc = !strncmp(bpf_program__section_name(prog), "tc", 2);
 113
 114                         tattr.data_in = tests[i].data_in;
 115                         tattr.data_size_in = tests[i].data_size_in;
 116
 117                         tattr.data_size_out = 0;
 118                         bpf_obj->bss->ifindex = *tests[i].ifindex;
 119                         bpf_obj->bss->ret = 0;
 120                         err = bpf_prog_test_run_opts(bpf_program__fd(prog), &tattr);
 121                         sprintf(buf, "err: %s [%s]", tests[i].msg, bpf_program__name(prog));
 122
 123                         if (at_tc && tests[i].success_on_tc)
 124                                 ASSERT_GE(err, 0, buf);
 125                         else
 126                                 ASSERT_EQ(err, tests[i].err, buf);
 127                         sprintf(buf, "ret: %s [%s]", tests[i].msg, bpf_program__name(prog));
 128                         if (at_tc && tests[i].success_on_tc)
 129                                 ASSERT_GE(bpf_obj->bss->ret, 0, buf);
 130                         else
 131                                 ASSERT_EQ(bpf_obj->bss->ret, tests[i].ret, buf);
 132                 }
 133         }
 134
 135 out:
 136         if (bpf_obj)
 137                 empty_skb__destroy(bpf_obj);
 138         if (tok)
 139                 close_netns(tok);
 140         SYS_NOFAIL("ip netns del empty_skb");
 141 }