1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
// SPDX-FileCopyrightText: 2026 Dilluti0n <[email protected]>
// SPDX-License-Identifier: GPL-3.0-or-later
use anyhow::{Result, Error};
use std::sync::{
atomic::{AtomicBool, Ordering}
};
use crate::{log::LogLevel, log_println, opt};
use super::{exec_process, INJECT_MARK, IS_U32_SUPPORTED};
static IS_XT_U32_LOADED_BY_US: AtomicBool = AtomicBool::new(false);
const DPIBREAK_CHAIN: &str = "DPIBREAK";
pub struct IPTables {
cmd: &'static str,
}
impl IPTables {
pub fn new(is_ipv6: bool) -> Result<Self> {
Ok(Self {
cmd: if is_ipv6 { "ip6tables" } else { "iptables" },
})
}
fn run(&self, args: &[&str]) -> Result<()> {
let mut full_args = Vec::with_capacity(args.len() + 1);
full_args.push(self.cmd);
full_args.extend_from_slice(args);
exec_process(&full_args, None)
}
pub fn new_chain(&self, table: &str, chain: &str) -> Result<()> {
self.run(&["-t", table, "-N", chain])
}
pub fn flush_chain(&self, table: &str, chain: &str) -> Result<()> {
self.run(&["-t", table, "-F", chain])
}
pub fn delete_chain(&self, table: &str, chain: &str) -> Result<()> {
self.run(&["-t", table, "-X", chain])
}
pub fn insert(&self, table: &str, chain: &str, rule: &[&str], pos: i32) -> Result<()> {
let pos_str = pos.to_string();
let mut args = vec!["-t", table, "-I", chain, &pos_str];
args.extend_from_slice(rule);
self.run(&args)
}
pub fn append(&self, table: &str, chain: &str, rule: &[&str]) -> Result<()> {
let mut args = vec!["-t", table, "-A", chain];
args.extend_from_slice(rule);
self.run(&args)
}
pub fn delete(&self, table: &str, chain: &str, rule: &[&str]) -> Result<()> {
let mut args = vec!["-t", table, "-D", chain];
args.extend_from_slice(rule);
self.run(&args)
}
}
fn is_xt_u32_loaded() -> bool {
std::fs::read_to_string("/proc/modules")
.map(|s| s.lines().any(|l| l.starts_with("xt_u32 ")))
.unwrap_or(false)
}
fn ensure_xt_u32() -> Result<()> {
let before = is_xt_u32_loaded();
_ = exec_process(&["modprobe", "-q", "xt_u32"], None);
let after = is_xt_u32_loaded();
if !before && after {
IS_XT_U32_LOADED_BY_US.store(true, Ordering::Relaxed);
}
Ok(())
}
fn is_u32_supported(ipt: &IPTables) -> bool {
if IS_U32_SUPPORTED.load(Ordering::Relaxed) {
return true;
}
if ensure_xt_u32().is_err() {
log_println!(LogLevel::Warning, "xt_u32 not supported");
return false;
}
log_println!(LogLevel::Info, "xt_u32 loaded");
let rule = ["-m", "u32", "--u32", "0x0=0x0", "-j", "RETURN"];
match ipt.insert("raw", "PREROUTING", &rule, 1) {
Ok(_) => {
_ = ipt.delete("raw", "PREROUTING", &rule);
IS_U32_SUPPORTED.store(true, Ordering::Relaxed);
true
}
Err(_) => false
}
}
pub fn iptables_err(e: impl ToString) -> Error {
Error::msg(format!("iptables: {}", e.to_string()))
}
pub fn install_iptables_rules(ipt: &IPTables) -> Result<()> {
let q_num = crate::opt::queue_num().to_string();
// prevent inf loop
let mark = format!("{:#x}", INJECT_MARK);
let mut rule = vec![
"-p", "tcp", "--dport", "443",
"-j", "NFQUEUE", "--queue-num", &q_num, "--queue-bypass"
];
if is_u32_supported(ipt) {
const U32: &str = "0>>22&0x3C @ 12>>26&0x3C @ 0>>24&0xFF=0x16 && \
0>>22&0x3C @ 12>>26&0x3C @ 2>>24&0xFF=0x01";
rule.extend_from_slice(&["-m", "u32", "--u32", U32]);
}
ipt.new_chain("mangle", DPIBREAK_CHAIN).map_err(iptables_err)?;
ipt.insert(
"mangle",
DPIBREAK_CHAIN,
&["-m", "mark", "--mark", &mark, "-j", "RETURN"],
1
).map_err(iptables_err)?;
if opt::fake_autottl() {
let synack_rule = vec![
"-p", "tcp",
"--sport", "443",
"-m", "tcp", "--tcp-flags", "SYN,ACK", "SYN,ACK",
"-j", "NFQUEUE", "--queue-num", &q_num, "--queue-bypass",
];
ipt.append("mangle", DPIBREAK_CHAIN, &synack_rule).map_err(iptables_err)?;
log_println!(LogLevel::Info, "{}: add SYN/ACK learning rule on mangle/{}", ipt.cmd, DPIBREAK_CHAIN);
ipt.insert("mangle", "INPUT", &["-j", DPIBREAK_CHAIN], 1).map_err(iptables_err)?;
log_println!(LogLevel::Info, "{}: add jump to {} chain on INPUT", ipt.cmd, DPIBREAK_CHAIN);
}
ipt.append("mangle", DPIBREAK_CHAIN, &rule).map_err(iptables_err)?;
log_println!(LogLevel::Info, "{}: new chain {} on table mangle", ipt.cmd, DPIBREAK_CHAIN);
ipt.insert("mangle", "POSTROUTING", &["-j", DPIBREAK_CHAIN], 1).map_err(iptables_err)?;
log_println!(LogLevel::Info, "{}: add jump to {} chain on POSTROUTING", ipt.cmd, DPIBREAK_CHAIN);
Ok(())
}
pub fn cleanup_iptables_rules(ipt: &IPTables) -> Result<()> {
if ipt.delete("mangle", "POSTROUTING", &["-j", DPIBREAK_CHAIN]).is_ok() {
log_println!(LogLevel::Info, "{}: delete jump to {} from mangle/POSTROUTING", ipt.cmd, DPIBREAK_CHAIN);
}
if opt::fake_autottl() && ipt.delete("mangle", "INPUT", &["-j", DPIBREAK_CHAIN]).is_ok() {
log_println!(LogLevel::Info, "{}: delete jump to {} from mangle/INPUT", ipt.cmd, DPIBREAK_CHAIN);
}
if ipt.flush_chain("mangle", DPIBREAK_CHAIN).is_ok() {
log_println!(LogLevel::Info, "{}: flush chain {}", ipt.cmd, DPIBREAK_CHAIN);
}
if ipt.delete_chain("mangle", DPIBREAK_CHAIN).is_ok() {
log_println!(LogLevel::Info, "{}: delete chain {}", ipt.cmd, DPIBREAK_CHAIN);
}
Ok(())
}
pub fn cleanup_xt_u32() -> Result<()> {
if IS_XT_U32_LOADED_BY_US.load(Ordering::Relaxed) {
exec_process(&["modprobe", "-q", "-r", "xt_u32"], None)?;
log_println!(LogLevel::Info, "cleanup: unload xt_u32");
}
Ok(())
}
|
