1 // SPDX-License-Identifier: GPL-2.0-only
2
3 /*
4 * Copyright 2021 Google LLC.
5 */
6
7 #include <errno.h>
8 #include <linux/bpf.h>
9 #include <bpf/bpf_helpers.h>
10
11 __u32 invocations = 0;
12 __u32 assertion_error = 0;
13 __u32 retval_value = 0;
14 __u32 ctx_retval_value = 0;
15 __u32 page_size = 0;
16
17 SEC("cgroup/getsockopt")
18 int get_retval(struct bpf_sockopt *ctx)
19 {
20 retval_value = bpf_get_retval();
21 ctx_retval_value = ctx->retval;
22 __sync_fetch_and_add(&invocations, 1);
23
24 /* optval larger than PAGE_SIZE use kernel's buffer. */
25 if (ctx->optlen > page_size)
26 ctx->optlen = 0;
27
28 return 1;
29 }
30
31 SEC("cgroup/getsockopt")
32 int set_eisconn(struct bpf_sockopt *ctx)
33 {
34 __sync_fetch_and_add(&invocations, 1);
35
36 if (bpf_set_retval(-EISCONN))
37 assertion_error = 1;
38
39 /* optval larger than PAGE_SIZE use kernel's buffer. */
40 if (ctx->optlen > page_size)
41 ctx->optlen = 0;
42
43 return 1;
44 }
45
46 SEC("cgroup/getsockopt")
47 int clear_retval(struct bpf_sockopt *ctx)
48 {
49 __sync_fetch_and_add(&invocations, 1);
50
51 ctx->retval = 0;
52
53 /* optval larger than PAGE_SIZE use kernel's buffer. */
54 if (ctx->optlen > page_size)
55 ctx->optlen = 0;
56
57 return 1;
58 }
59
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