1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 #include "test_xdp_attach_fail.skel.h"
4 
5 #define IFINDEX_LO 1
6 #define XDP_FLAGS_REPLACE		(1U << 4)
7 
8 static void test_xdp_attach(const char *file)
9 {
10 	__u32 duration = 0, id1, id2, id0 = 0, len;
11 	struct bpf_object *obj1, *obj2, *obj3;
12 	struct bpf_prog_info info = {};
13 	int err, fd1, fd2, fd3;
14 	LIBBPF_OPTS(bpf_xdp_attach_opts, opts);
15 
16 	len = sizeof(info);
17 
18 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj1, &fd1);
19 	if (CHECK_FAIL(err))
20 		return;
21 	err = bpf_prog_get_info_by_fd(fd1, &info, &len);
22 	if (CHECK_FAIL(err))
23 		goto out_1;
24 	id1 = info.id;
25 
26 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj2, &fd2);
27 	if (CHECK_FAIL(err))
28 		goto out_1;
29 
30 	memset(&info, 0, sizeof(info));
31 	err = bpf_prog_get_info_by_fd(fd2, &info, &len);
32 	if (CHECK_FAIL(err))
33 		goto out_2;
34 	id2 = info.id;
35 
36 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj3, &fd3);
37 	if (CHECK_FAIL(err))
38 		goto out_2;
39 
40 	err = bpf_xdp_attach(IFINDEX_LO, fd1, XDP_FLAGS_REPLACE, &opts);
41 	if (CHECK(err, "load_ok", "initial load failed"))
42 		goto out_close;
43 
44 	err = bpf_xdp_query_id(IFINDEX_LO, 0, &id0);
45 	if (CHECK(err || id0 != id1, "id1_check",
46 		  "loaded prog id %u != id1 %u, err %d", id0, id1, err))
47 		goto out_close;
48 
49 	err = bpf_xdp_attach(IFINDEX_LO, fd2, XDP_FLAGS_REPLACE, &opts);
50 	if (CHECK(!err, "load_fail", "load with expected id didn't fail"))
51 		goto out;
52 
53 	opts.old_prog_fd = fd1;
54 	err = bpf_xdp_attach(IFINDEX_LO, fd2, 0, &opts);
55 	if (CHECK(err, "replace_ok", "replace valid old_fd failed"))
56 		goto out;
57 	err = bpf_xdp_query_id(IFINDEX_LO, 0, &id0);
58 	if (CHECK(err || id0 != id2, "id2_check",
59 		  "loaded prog id %u != id2 %u, err %d", id0, id2, err))
60 		goto out_close;
61 
62 	err = bpf_xdp_attach(IFINDEX_LO, fd3, 0, &opts);
63 	if (CHECK(!err, "replace_fail", "replace invalid old_fd didn't fail"))
64 		goto out;
65 
66 	err = bpf_xdp_detach(IFINDEX_LO, 0, &opts);
67 	if (CHECK(!err, "remove_fail", "remove invalid old_fd didn't fail"))
68 		goto out;
69 
70 	opts.old_prog_fd = fd2;
71 	err = bpf_xdp_detach(IFINDEX_LO, 0, &opts);
72 	if (CHECK(err, "remove_ok", "remove valid old_fd failed"))
73 		goto out;
74 
75 	err = bpf_xdp_query_id(IFINDEX_LO, 0, &id0);
76 	if (CHECK(err || id0 != 0, "unload_check",
77 		  "loaded prog id %u != 0, err %d", id0, err))
78 		goto out_close;
79 out:
80 	bpf_xdp_detach(IFINDEX_LO, 0, NULL);
81 out_close:
82 	bpf_object__close(obj3);
83 out_2:
84 	bpf_object__close(obj2);
85 out_1:
86 	bpf_object__close(obj1);
87 }
88 
89 #define ERRMSG_LEN 64
90 
91 struct xdp_errmsg {
92 	char msg[ERRMSG_LEN];
93 };
94 
95 static void on_xdp_errmsg(void *ctx, int cpu, void *data, __u32 size)
96 {
97 	struct xdp_errmsg *ctx_errmg = ctx, *tp_errmsg = data;
98 
99 	memcpy(&ctx_errmg->msg, &tp_errmsg->msg, ERRMSG_LEN);
100 }
101 
102 static const char tgt_errmsg[] = "Invalid XDP flags for BPF link attachment";
103 
104 static void test_xdp_attach_fail(const char *file)
105 {
106 	struct test_xdp_attach_fail *skel = NULL;
107 	struct xdp_errmsg errmsg = {};
108 	struct perf_buffer *pb = NULL;
109 	struct bpf_object *obj = NULL;
110 	int err, fd_xdp;
111 
112 	LIBBPF_OPTS(bpf_link_create_opts, opts);
113 
114 	skel = test_xdp_attach_fail__open_and_load();
115 	if (!ASSERT_OK_PTR(skel, "test_xdp_attach_fail__open_and_load"))
116 		goto out_close;
117 
118 	err = test_xdp_attach_fail__attach(skel);
119 	if (!ASSERT_EQ(err, 0, "test_xdp_attach_fail__attach"))
120 		goto out_close;
121 
122 	/* set up perf buffer */
123 	pb = perf_buffer__new(bpf_map__fd(skel->maps.xdp_errmsg_pb), 1,
124 			      on_xdp_errmsg, NULL, &errmsg, NULL);
125 	if (!ASSERT_OK_PTR(pb, "perf_buffer__new"))
126 		goto out_close;
127 
128 	err = bpf_prog_test_load(file, BPF_PROG_TYPE_XDP, &obj, &fd_xdp);
129 	if (!ASSERT_EQ(err, 0, "bpf_prog_test_load"))
130 		goto out_close;
131 
132 	opts.flags = 0xFF; // invalid flags to fail to attach XDP prog
133 	err = bpf_link_create(fd_xdp, IFINDEX_LO, BPF_XDP, &opts);
134 	if (!ASSERT_EQ(err, -EINVAL, "bpf_link_create"))
135 		goto out_close;
136 
137 	/* read perf buffer */
138 	err = perf_buffer__poll(pb, 100);
139 	if (!ASSERT_GT(err, -1, "perf_buffer__poll"))
140 		goto out_close;
141 
142 	ASSERT_STRNEQ((const char *) errmsg.msg, tgt_errmsg,
143 		      42 /* strlen(tgt_errmsg) */, "check error message");
144 
145 out_close:
146 	perf_buffer__free(pb);
147 	bpf_object__close(obj);
148 	test_xdp_attach_fail__destroy(skel);
149 }
150 
151 void serial_test_xdp_attach(void)
152 {
153 	if (test__start_subtest("xdp_attach"))
154 		test_xdp_attach("./test_xdp.bpf.o");
155 	if (test__start_subtest("xdp_attach_dynptr"))
156 		test_xdp_attach("./test_xdp_dynptr.bpf.o");
157 	if (test__start_subtest("xdp_attach_failed"))
158 		test_xdp_attach_fail("./xdp_dummy.bpf.o");
159 }
160