tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2018 Facebook
3
4#include <linux/bpf.h>
5#include <sys/socket.h>
6
7#include "bpf_helpers.h"
8#include "bpf_endian.h"
9
10struct socket_cookie {
11 __u64 cookie_key;
12 __u32 cookie_value;
13};
14
15struct {
16 __uint(type, BPF_MAP_TYPE_SK_STORAGE);
17 __uint(map_flags, BPF_F_NO_PREALLOC);
18 __type(key, int);
19 __type(value, struct socket_cookie);
20} socket_cookies SEC(".maps");
21
22SEC("cgroup/connect6")
23int set_cookie(struct bpf_sock_addr *ctx)
24{
25 struct socket_cookie *p;
26
27 if (ctx->family != AF_INET6 || ctx->user_family != AF_INET6)
28 return 1;
29
30 p = bpf_sk_storage_get(&socket_cookies, ctx->sk, 0,
31 BPF_SK_STORAGE_GET_F_CREATE);
32 if (!p)
33 return 1;
34
35 p->cookie_value = 0xFF;
36 p->cookie_key = bpf_get_socket_cookie(ctx);
37
38 return 1;
39}
40
41SEC("sockops")
42int update_cookie(struct bpf_sock_ops *ctx)
43{
44 struct bpf_sock *sk;
45 struct socket_cookie *p;
46
47 if (ctx->family != AF_INET6)
48 return 1;
49
50 if (ctx->op != BPF_SOCK_OPS_TCP_CONNECT_CB)
51 return 1;
52
53 if (!ctx->sk)
54 return 1;
55
56 p = bpf_sk_storage_get(&socket_cookies, ctx->sk, 0, 0);
57 if (!p)
58 return 1;
59
60 if (p->cookie_key != bpf_get_socket_cookie(ctx))
61 return 1;
62
63 p->cookie_value = (ctx->local_port << 8) | p->cookie_value;
64
65 return 1;
66}
67
68int _version SEC("version") = 1;
69
70char _license[] SEC("license") = "GPL";