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 = (void *)buf + sizeof(struct ethhdr);
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 	struct perf_buffer_opts pb_opts = {};
53 
54 	/* Load XDP program to introspect */
55 	pkt_skel = test_xdp__open_and_load();
56 	if (CHECK(!pkt_skel, "pkt_skel_load", "test_xdp skeleton failed\n"))
57 		return;
58 
59 	pkt_fd = bpf_program__fd(pkt_skel->progs._xdp_tx_iptunnel);
60 
61 	map_fd = bpf_map__fd(pkt_skel->maps.vip2tnl);
62 	bpf_map_update_elem(map_fd, &key4, &value4, 0);
63 
64 	/* Load trace program */
65 	ftrace_skel = test_xdp_bpf2bpf__open();
66 	if (CHECK(!ftrace_skel, "__open", "ftrace skeleton failed\n"))
67 		goto out;
68 
69 	/* Demonstrate the bpf_program__set_attach_target() API rather than
70 	 * the load with options, i.e. opts.attach_prog_fd.
71 	 */
72 	prog = ftrace_skel->progs.trace_on_entry;
73 	bpf_program__set_expected_attach_type(prog, BPF_TRACE_FENTRY);
74 	bpf_program__set_attach_target(prog, pkt_fd, "_xdp_tx_iptunnel");
75 
76 	prog = ftrace_skel->progs.trace_on_exit;
77 	bpf_program__set_expected_attach_type(prog, BPF_TRACE_FEXIT);
78 	bpf_program__set_attach_target(prog, pkt_fd, "_xdp_tx_iptunnel");
79 
80 	err = test_xdp_bpf2bpf__load(ftrace_skel);
81 	if (CHECK(err, "__load", "ftrace skeleton failed\n"))
82 		goto out;
83 
84 	err = test_xdp_bpf2bpf__attach(ftrace_skel);
85 	if (CHECK(err, "ftrace_attach", "ftrace attach failed: %d\n", err))
86 		goto out;
87 
88 	/* Set up perf buffer */
89 	pb_opts.sample_cb = on_sample;
90 	pb_opts.ctx = &passed;
91 	pb = perf_buffer__new(bpf_map__fd(ftrace_skel->maps.perf_buf_map),
92 			      1, &pb_opts);
93 	if (CHECK(IS_ERR(pb), "perf_buf__new", "err %ld\n", PTR_ERR(pb)))
94 		goto out;
95 
96 	/* Run test program */
97 	err = bpf_prog_test_run(pkt_fd, 1, &pkt_v4, sizeof(pkt_v4),
98 				buf, &size, &retval, &duration);
99 
100 	if (CHECK(err || retval != XDP_TX || size != 74 ||
101 		  iph->protocol != IPPROTO_IPIP, "ipv4",
102 		  "err %d errno %d retval %d size %d\n",
103 		  err, errno, retval, size))
104 		goto out;
105 
106 	/* Make sure bpf_xdp_output() was triggered and it sent the expected
107 	 * data to the perf ring buffer.
108 	 */
109 	err = perf_buffer__poll(pb, 100);
110 	if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
111 		goto out;
112 
113 	CHECK_FAIL(!passed);
114 
115 	/* Verify test results */
116 	if (CHECK(ftrace_skel->bss->test_result_fentry != if_nametoindex("lo"),
117 		  "result", "fentry failed err %llu\n",
118 		  ftrace_skel->bss->test_result_fentry))
119 		goto out;
120 
121 	CHECK(ftrace_skel->bss->test_result_fexit != XDP_TX, "result",
122 	      "fexit failed err %llu\n", ftrace_skel->bss->test_result_fexit);
123 
124 out:
125 	if (pb)
126 		perf_buffer__free(pb);
127 	test_xdp__destroy(pkt_skel);
128 	test_xdp_bpf2bpf__destroy(ftrace_skel);
129 }
130