1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 #include <network_helpers.h>
4 #include <net/if.h>
5 #include "test_xdp.skel.h"
6 #include "test_xdp_bpf2bpf.skel.h"
7 
8 struct meta {
9 	int ifindex;
10 	int pkt_len;
11 };
12 
13 static void on_sample(void *ctx, int cpu, void *data, __u32 size)
14 {
15 	int duration = 0;
16 	struct meta *meta = (struct meta *)data;
17 	struct ipv4_packet *trace_pkt_v4 = data + sizeof(*meta);
18 
19 	if (CHECK(size < sizeof(pkt_v4) + sizeof(*meta),
20 		  "check_size", "size %u < %zu\n",
21 		  size, sizeof(pkt_v4) + sizeof(*meta)))
22 		return;
23 
24 	if (CHECK(meta->ifindex != if_nametoindex("lo"), "check_meta_ifindex",
25 		  "meta->ifindex = %d\n", meta->ifindex))
26 		return;
27 
28 	if (CHECK(meta->pkt_len != sizeof(pkt_v4), "check_meta_pkt_len",
29 		  "meta->pkt_len = %zd\n", sizeof(pkt_v4)))
30 		return;
31 
32 	if (CHECK(memcmp(trace_pkt_v4, &pkt_v4, sizeof(pkt_v4)),
33 		  "check_packet_content", "content not the same\n"))
34 		return;
35 
36 	*(bool *)ctx = true;
37 }
38 
39 void test_xdp_bpf2bpf(void)
40 {
41 	__u32 duration = 0, retval, size;
42 	char buf[128];
43 	int err, pkt_fd, map_fd;
44 	bool passed = false;
45 	struct iphdr iph;
46 	struct iptnl_info value4 = {.family = AF_INET};
47 	struct test_xdp *pkt_skel = NULL;
48 	struct test_xdp_bpf2bpf *ftrace_skel = NULL;
49 	struct vip key4 = {.protocol = 6, .family = AF_INET};
50 	struct bpf_program *prog;
51 	struct perf_buffer *pb = NULL;
52 
53 	/* Load XDP program to introspect */
54 	pkt_skel = test_xdp__open_and_load();
55 	if (CHECK(!pkt_skel, "pkt_skel_load", "test_xdp skeleton failed\n"))
56 		return;
57 
58 	pkt_fd = bpf_program__fd(pkt_skel->progs._xdp_tx_iptunnel);
59 
60 	map_fd = bpf_map__fd(pkt_skel->maps.vip2tnl);
61 	bpf_map_update_elem(map_fd, &key4, &value4, 0);
62 
63 	/* Load trace program */
64 	ftrace_skel = test_xdp_bpf2bpf__open();
65 	if (CHECK(!ftrace_skel, "__open", "ftrace skeleton failed\n"))
66 		goto out;
67 
68 	/* Demonstrate the bpf_program__set_attach_target() API rather than
69 	 * the load with options, i.e. opts.attach_prog_fd.
70 	 */
71 	prog = ftrace_skel->progs.trace_on_entry;
72 	bpf_program__set_expected_attach_type(prog, BPF_TRACE_FENTRY);
73 	bpf_program__set_attach_target(prog, pkt_fd, "_xdp_tx_iptunnel");
74 
75 	prog = ftrace_skel->progs.trace_on_exit;
76 	bpf_program__set_expected_attach_type(prog, BPF_TRACE_FEXIT);
77 	bpf_program__set_attach_target(prog, pkt_fd, "_xdp_tx_iptunnel");
78 
79 	err = test_xdp_bpf2bpf__load(ftrace_skel);
80 	if (CHECK(err, "__load", "ftrace skeleton failed\n"))
81 		goto out;
82 
83 	err = test_xdp_bpf2bpf__attach(ftrace_skel);
84 	if (CHECK(err, "ftrace_attach", "ftrace attach failed: %d\n", err))
85 		goto out;
86 
87 	/* Set up perf buffer */
88 	pb = perf_buffer__new(bpf_map__fd(ftrace_skel->maps.perf_buf_map), 1,
89 			      on_sample, NULL, &passed, NULL);
90 	if (!ASSERT_OK_PTR(pb, "perf_buf__new"))
91 		goto out;
92 
93 	/* Run test program */
94 	err = bpf_prog_test_run(pkt_fd, 1, &pkt_v4, sizeof(pkt_v4),
95 				buf, &size, &retval, &duration);
96 	memcpy(&iph, buf + sizeof(struct ethhdr), sizeof(iph));
97 	if (CHECK(err || retval != XDP_TX || size != 74 ||
98 		  iph.protocol != IPPROTO_IPIP, "ipv4",
99 		  "err %d errno %d retval %d size %d\n",
100 		  err, errno, retval, size))
101 		goto out;
102 
103 	/* Make sure bpf_xdp_output() was triggered and it sent the expected
104 	 * data to the perf ring buffer.
105 	 */
106 	err = perf_buffer__poll(pb, 100);
107 	if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
108 		goto out;
109 
110 	CHECK_FAIL(!passed);
111 
112 	/* Verify test results */
113 	if (CHECK(ftrace_skel->bss->test_result_fentry != if_nametoindex("lo"),
114 		  "result", "fentry failed err %llu\n",
115 		  ftrace_skel->bss->test_result_fentry))
116 		goto out;
117 
118 	CHECK(ftrace_skel->bss->test_result_fexit != XDP_TX, "result",
119 	      "fexit failed err %llu\n", ftrace_skel->bss->test_result_fexit);
120 
121 out:
122 	if (pb)
123 		perf_buffer__free(pb);
124 	test_xdp__destroy(pkt_skel);
125 	test_xdp_bpf2bpf__destroy(ftrace_skel);
126 }
127