1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 #include <net/if.h>
4 #include "test_xdp.skel.h"
5 #include "test_xdp_bpf2bpf.skel.h"
6 
7 struct meta {
8 	int ifindex;
9 	int pkt_len;
10 };
11 
12 static void on_sample(void *ctx, int cpu, void *data, __u32 size)
13 {
14 	int duration = 0;
15 	struct meta *meta = (struct meta *)data;
16 	struct ipv4_packet *trace_pkt_v4 = data + sizeof(*meta);
17 
18 	if (CHECK(size < sizeof(pkt_v4) + sizeof(*meta),
19 		  "check_size", "size %u < %zu\n",
20 		  size, sizeof(pkt_v4) + sizeof(*meta)))
21 		return;
22 
23 	if (CHECK(meta->ifindex != if_nametoindex("lo"), "check_meta_ifindex",
24 		  "meta->ifindex = %d\n", meta->ifindex))
25 		return;
26 
27 	if (CHECK(meta->pkt_len != sizeof(pkt_v4), "check_meta_pkt_len",
28 		  "meta->pkt_len = %zd\n", sizeof(pkt_v4)))
29 		return;
30 
31 	if (CHECK(memcmp(trace_pkt_v4, &pkt_v4, sizeof(pkt_v4)),
32 		  "check_packet_content", "content not the same\n"))
33 		return;
34 
35 	*(bool *)ctx = true;
36 }
37 
38 void test_xdp_bpf2bpf(void)
39 {
40 	__u32 duration = 0, retval, size;
41 	char buf[128];
42 	int err, pkt_fd, map_fd;
43 	bool passed = false;
44 	struct iphdr *iph = (void *)buf + sizeof(struct ethhdr);
45 	struct iptnl_info value4 = {.family = AF_INET};
46 	struct test_xdp *pkt_skel = NULL;
47 	struct test_xdp_bpf2bpf *ftrace_skel = NULL;
48 	struct vip key4 = {.protocol = 6, .family = AF_INET};
49 	struct bpf_program *prog;
50 	struct perf_buffer *pb = NULL;
51 	struct perf_buffer_opts pb_opts = {};
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_opts.sample_cb = on_sample;
89 	pb_opts.ctx = &passed;
90 	pb = perf_buffer__new(bpf_map__fd(ftrace_skel->maps.perf_buf_map),
91 			      1, &pb_opts);
92 	if (CHECK(IS_ERR(pb), "perf_buf__new", "err %ld\n", PTR_ERR(pb)))
93 		goto out;
94 
95 	/* Run test program */
96 	err = bpf_prog_test_run(pkt_fd, 1, &pkt_v4, sizeof(pkt_v4),
97 				buf, &size, &retval, &duration);
98 
99 	if (CHECK(err || retval != XDP_TX || size != 74 ||
100 		  iph->protocol != IPPROTO_IPIP, "ipv4",
101 		  "err %d errno %d retval %d size %d\n",
102 		  err, errno, retval, size))
103 		goto out;
104 
105 	/* Make sure bpf_xdp_output() was triggered and it sent the expected
106 	 * data to the perf ring buffer.
107 	 */
108 	err = perf_buffer__poll(pb, 100);
109 	if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
110 		goto out;
111 
112 	CHECK_FAIL(!passed);
113 
114 	/* Verify test results */
115 	if (CHECK(ftrace_skel->bss->test_result_fentry != if_nametoindex("lo"),
116 		  "result", "fentry failed err %llu\n",
117 		  ftrace_skel->bss->test_result_fentry))
118 		goto out;
119 
120 	CHECK(ftrace_skel->bss->test_result_fexit != XDP_TX, "result",
121 	      "fexit failed err %llu\n", ftrace_skel->bss->test_result_fexit);
122 
123 out:
124 	if (pb)
125 		perf_buffer__free(pb);
126 	test_xdp__destroy(pkt_skel);
127 	test_xdp_bpf2bpf__destroy(ftrace_skel);
128 }
129