1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright Amazon.com Inc. or its affiliates. */
3 #include "bpf_iter.h"
4 #include "bpf_tracing_net.h"
5 #include <bpf/bpf_helpers.h>
6 #include <limits.h>
7 
8 #define AUTOBIND_LEN 6
9 char sun_path[AUTOBIND_LEN];
10 
11 #define NR_CASES 5
12 int sndbuf_setsockopt[NR_CASES] = {-1, 0, 8192, INT_MAX / 2, INT_MAX};
13 int sndbuf_getsockopt[NR_CASES] = {-1, -1, -1, -1, -1};
14 int sndbuf_getsockopt_expected[NR_CASES];
15 
cmpname(struct unix_sock * unix_sk)16 static inline int cmpname(struct unix_sock *unix_sk)
17 {
18 	int i;
19 
20 	for (i = 0; i < AUTOBIND_LEN; i++) {
21 		if (unix_sk->addr->name->sun_path[i] != sun_path[i])
22 			return -1;
23 	}
24 
25 	return 0;
26 }
27 
28 SEC("iter/unix")
change_sndbuf(struct bpf_iter__unix * ctx)29 int change_sndbuf(struct bpf_iter__unix *ctx)
30 {
31 	struct unix_sock *unix_sk = ctx->unix_sk;
32 	int i, err;
33 
34 	if (!unix_sk || !unix_sk->addr)
35 		return 0;
36 
37 	if (unix_sk->addr->name->sun_path[0])
38 		return 0;
39 
40 	if (cmpname(unix_sk))
41 		return 0;
42 
43 	for (i = 0; i < NR_CASES; i++) {
44 		err = bpf_setsockopt(unix_sk, SOL_SOCKET, SO_SNDBUF,
45 				     &sndbuf_setsockopt[i],
46 				     sizeof(sndbuf_setsockopt[i]));
47 		if (err)
48 			break;
49 
50 		err = bpf_getsockopt(unix_sk, SOL_SOCKET, SO_SNDBUF,
51 				     &sndbuf_getsockopt[i],
52 				     sizeof(sndbuf_getsockopt[i]));
53 		if (err)
54 			break;
55 	}
56 
57 	return 0;
58 }
59 
60 char _license[] SEC("license") = "GPL";
61