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
3#include <string.h>
4
5#include <linux/stddef.h>
6#include <linux/bpf.h>
7
8#include <sys/socket.h>
9
10#include <bpf/bpf_helpers.h>
11#include <bpf/bpf_endian.h>
12
13#define VERDICT_REJECT 0
14#define VERDICT_PROCEED 1
15
16int port;
17
18SEC("cgroup/connect4")
19int connect_v4_dropper(struct bpf_sock_addr *ctx)
20{
21 if (ctx->type != SOCK_STREAM)
22 return VERDICT_PROCEED;
23 if (ctx->user_port == bpf_htons(port))
24 return VERDICT_REJECT;
25 return VERDICT_PROCEED;
26}
27
28char _license[] SEC("license") = "GPL";