1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2022 Facebook */
3
4 #include <test_progs.h>
5 #include "test_custom_sec_handlers.skel.h"
6
7 #define COOKIE_ABC1 1
8 #define COOKIE_ABC2 2
9 #define COOKIE_CUSTOM 3
10 #define COOKIE_FALLBACK 4
11 #define COOKIE_KPROBE 5
12
13 static int custom_setup_prog(struct bpf_program *prog, long cookie)
14 {
15 if (cookie == COOKIE_ABC1)
16 bpf_program__set_autoload(prog, false);
17
18 return 0;
19 }
20
21 static int custom_prepare_load_prog(struct bpf_program *prog,
22 struct bpf_prog_load_opts *opts, long cookie)
23 {
24 if (cookie == COOKIE_FALLBACK)
25 opts->prog_flags |= BPF_F_SLEEPABLE;
26 else if (cookie == COOKIE_ABC1)
27 ASSERT_FALSE(true, "unexpected preload for abc");
28
29 return 0;
30 }
31
32 static int custom_attach_prog(const struct bpf_program *prog, long cookie,
33 struct bpf_link **link)
34 {
35 switch (cookie) {
36 case COOKIE_ABC2:
37 *link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
38 return libbpf_get_error(*link);
39 case COOKIE_CUSTOM:
40 *link = bpf_program__attach_tracepoint(prog, "syscalls", "sys_enter_nanosleep");
41 return libbpf_get_error(*link);
42 case COOKIE_KPROBE:
43 case COOKIE_FALLBACK:
44 /* no auto-attach for SEC("xyz") and SEC("kprobe") */
45 *link = NULL;
46 return 0;
47 default:
48 ASSERT_FALSE(true, "unexpected cookie");
49 return -EINVAL;
50 }
51 }
52
53 static int abc1_id;
54 static int abc2_id;
55 static int custom_id;
56 static int fallback_id;
57 static int kprobe_id;
58
59 __attribute__((constructor))
60 static void register_sec_handlers(void)
61 {
62 LIBBPF_OPTS(libbpf_prog_handler_opts, abc1_opts,
63 .cookie = COOKIE_ABC1,
64 .prog_setup_fn = custom_setup_prog,
65 .prog_prepare_load_fn = custom_prepare_load_prog,
66 .prog_attach_fn = NULL,
67 );
68 LIBBPF_OPTS(libbpf_prog_handler_opts, abc2_opts,
69 .cookie = COOKIE_ABC2,
70 .prog_setup_fn = custom_setup_prog,
71 .prog_prepare_load_fn = custom_prepare_load_prog,
72 .prog_attach_fn = custom_attach_prog,
73 );
74 LIBBPF_OPTS(libbpf_prog_handler_opts, custom_opts,
75 .cookie = COOKIE_CUSTOM,
76 .prog_setup_fn = NULL,
77 .prog_prepare_load_fn = NULL,
78 .prog_attach_fn = custom_attach_prog,
79 );
80
81 abc1_id = libbpf_register_prog_handler("abc", BPF_PROG_TYPE_RAW_TRACEPOINT, 0, &abc1_opts);
82 abc2_id = libbpf_register_prog_handler("abc/", BPF_PROG_TYPE_RAW_TRACEPOINT, 0, &abc2_opts);
83 custom_id = libbpf_register_prog_handler("custom+", BPF_PROG_TYPE_TRACEPOINT, 0, &custom_opts);
84 }
85
86 __attribute__((destructor))
87 static void unregister_sec_handlers(void)
88 {
89 libbpf_unregister_prog_handler(abc1_id);
90 libbpf_unregister_prog_handler(abc2_id);
91 libbpf_unregister_prog_handler(custom_id);
92 }
93
94 void test_custom_sec_handlers(void)
95 {
96 LIBBPF_OPTS(libbpf_prog_handler_opts, opts,
97 .prog_setup_fn = custom_setup_prog,
98 .prog_prepare_load_fn = custom_prepare_load_prog,
99 .prog_attach_fn = custom_attach_prog,
100 );
101 struct test_custom_sec_handlers* skel;
102 int err;
103
104 ASSERT_GT(abc1_id, 0, "abc1_id");
105 ASSERT_GT(abc2_id, 0, "abc2_id");
106 ASSERT_GT(custom_id, 0, "custom_id");
107
108 /* override libbpf's handle of SEC("kprobe/...") but also allow pure
109 * SEC("kprobe") due to "kprobe+" specifier. Register it as
110 * TRACEPOINT, just for fun.
111 */
112 opts.cookie = COOKIE_KPROBE;
113 kprobe_id = libbpf_register_prog_handler("kprobe+", BPF_PROG_TYPE_TRACEPOINT, 0, &opts);
114 /* fallback treats everything as BPF_PROG_TYPE_SYSCALL program to test
115 * setting custom BPF_F_SLEEPABLE bit in preload handler
116 */
117 opts.cookie = COOKIE_FALLBACK;
118 fallback_id = libbpf_register_prog_handler(NULL, BPF_PROG_TYPE_SYSCALL, 0, &opts);
119
120 if (!ASSERT_GT(fallback_id, 0, "fallback_id") /* || !ASSERT_GT(kprobe_id, 0, "kprobe_id")*/) {
121 if (fallback_id > 0)
122 libbpf_unregister_prog_handler(fallback_id);
123 if (kprobe_id > 0)
124 libbpf_unregister_prog_handler(kprobe_id);
125 return;
126 }
127
128 /* open skeleton and validate assumptions */
129 skel = test_custom_sec_handlers__open();
130 if (!ASSERT_OK_PTR(skel, "skel_open"))
131 goto cleanup;
132
133 ASSERT_EQ(bpf_program__type(skel->progs.abc1), BPF_PROG_TYPE_RAW_TRACEPOINT, "abc1_type");
134 ASSERT_FALSE(bpf_program__autoload(skel->progs.abc1), "abc1_autoload");
135
136 ASSERT_EQ(bpf_program__type(skel->progs.abc2), BPF_PROG_TYPE_RAW_TRACEPOINT, "abc2_type");
137 ASSERT_EQ(bpf_program__type(skel->progs.custom1), BPF_PROG_TYPE_TRACEPOINT, "custom1_type");
138 ASSERT_EQ(bpf_program__type(skel->progs.custom2), BPF_PROG_TYPE_TRACEPOINT, "custom2_type");
139 ASSERT_EQ(bpf_program__type(skel->progs.kprobe1), BPF_PROG_TYPE_TRACEPOINT, "kprobe1_type");
140 ASSERT_EQ(bpf_program__type(skel->progs.xyz), BPF_PROG_TYPE_SYSCALL, "xyz_type");
141
142 skel->rodata->my_pid = getpid();
143
144 /* now attempt to load everything */
145 err = test_custom_sec_handlers__load(skel);
146 if (!ASSERT_OK(err, "skel_load"))
147 goto cleanup;
148
149 /* now try to auto-attach everything */
150 err = test_custom_sec_handlers__attach(skel);
151 if (!ASSERT_OK(err, "skel_attach"))
152 goto cleanup;
153
154 skel->links.xyz = bpf_program__attach(skel->progs.kprobe1);
155 ASSERT_EQ(errno, EOPNOTSUPP, "xyz_attach_err");
156 ASSERT_ERR_PTR(skel->links.xyz, "xyz_attach");
157
158 /* trigger programs */
159 usleep(1);
160
161 /* SEC("abc") is set to not auto-loaded */
162 ASSERT_FALSE(skel->bss->abc1_called, "abc1_called");
163 ASSERT_TRUE(skel->bss->abc2_called, "abc2_called");
164 ASSERT_TRUE(skel->bss->custom1_called, "custom1_called");
165 ASSERT_TRUE(skel->bss->custom2_called, "custom2_called");
166 /* SEC("kprobe") shouldn't be auto-attached */
167 ASSERT_FALSE(skel->bss->kprobe1_called, "kprobe1_called");
168 /* SEC("xyz") shouldn't be auto-attached */
169 ASSERT_FALSE(skel->bss->xyz_called, "xyz_called");
170
171 cleanup:
172 test_custom_sec_handlers__destroy(skel);
173
174 ASSERT_OK(libbpf_unregister_prog_handler(fallback_id), "unregister_fallback");
175 ASSERT_OK(libbpf_unregister_prog_handler(kprobe_id), "unregister_kprobe");
176 }
177
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