ostp/ostp-server/src/outbound.rs

544 lines
19 KiB
Rust

use anyhow::Result;
use tokio::net::TcpStream;
use tokio::time::Duration;
use serde::{Serialize, Deserialize};
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
pub enum OutboundAction {
Proxy,
Direct,
Block,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OutboundRule {
#[serde(default)]
pub domain_suffix: Vec<String>,
#[serde(default)]
pub ip_cidr: Vec<String>,
#[serde(default)]
pub protocol: Option<String>,
pub action: OutboundAction,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OutboundConfig {
pub enabled: bool,
pub protocol: String,
pub address: String,
pub port: u16,
pub rules: Vec<OutboundRule>,
pub default_action: OutboundAction,
}
// ── Target connection with outbound routing ──────────────────────────────────
pub async fn connect_target(
target: &str,
outbound: Option<&OutboundConfig>,
debug: bool,
) -> Result<TcpStream> {
let connect_timeout = Duration::from_secs(10);
if let Some(outbound) = outbound {
if outbound.enabled {
let action = select_outbound_action(target, "tcp", outbound, debug).await;
if action == OutboundAction::Block {
return Err(anyhow::anyhow!("blocked by outbound rule: {}", target));
}
if action == OutboundAction::Proxy {
let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
return match outbound.protocol.as_str() {
"socks5" => connect_via_socks5(&proxy_addr, target).await,
"http" => connect_via_http(&proxy_addr, target).await,
_ => tokio::time::timeout(connect_timeout, TcpStream::connect(target))
.await
.map_err(|_| anyhow::anyhow!("connect timeout ({}s): {}", connect_timeout.as_secs(), target))?
.map_err(Into::into),
};
}
}
}
tokio::time::timeout(connect_timeout, TcpStream::connect(target))
.await
.map_err(|_| anyhow::anyhow!("connect timeout ({}s): {}", connect_timeout.as_secs(), target))?
.map_err(Into::into)
}
// ── Rule matching ────────────────────────────────────────────────────────────
pub async fn select_outbound_action(
target: &str,
protocol: &str,
outbound: &OutboundConfig,
debug: bool,
) -> OutboundAction {
let (host, port) = match split_host_port(target) {
Some(v) => v,
None => return outbound.default_action,
};
let mut matched = None;
for rule in &outbound.rules {
if let Some(ref rule_proto) = rule.protocol {
if !rule_proto.is_empty() && rule_proto.to_lowercase() != protocol {
continue;
}
}
if rule.domain_suffix.is_empty() && rule.ip_cidr.is_empty() {
// Protocol-only rule match
matched = Some(rule.action);
break;
}
if match_domain_rule(&host, &rule.domain_suffix) {
matched = Some(rule.action);
break;
}
if match_ip_rule(&host, port, &rule.ip_cidr).await {
matched = Some(rule.action);
break;
}
}
let action = matched.unwrap_or(outbound.default_action);
if debug {
tracing::debug!("Outbound routing: target={target} action={action:?}");
}
action
}
fn match_domain_rule(host: &str, suffixes: &[String]) -> bool {
if suffixes.is_empty() {
return false;
}
let host = host.trim_end_matches('.').to_lowercase();
suffixes.iter().any(|suffix| {
let suffix = suffix.trim().trim_start_matches('.').to_lowercase();
!suffix.is_empty() && (host == suffix || host.ends_with(&format!(".{suffix}")))
})
}
async fn match_ip_rule(host: &str, port: u16, cidrs: &[String]) -> bool {
if cidrs.is_empty() {
return false;
}
let parsed: Vec<Cidr> = cidrs.iter().filter_map(|c| parse_cidr(c)).collect();
if parsed.is_empty() {
return false;
}
if let Ok(ip) = host.parse::<std::net::IpAddr>() {
return parsed.iter().any(|cidr| cidr.contains(&ip));
}
false
}
// ── SOCKS5 / HTTP CONNECT upstream proxy ─────────────────────────────────────
async fn connect_via_socks5(proxy_addr: &str, target: &str) -> Result<TcpStream> {
use tokio::io::{AsyncReadExt, AsyncWriteExt};
let mut stream = TcpStream::connect(proxy_addr).await?;
stream.write_all(&[0x05, 0x01, 0x00]).await?;
let mut reply = [0u8; 2];
stream.read_exact(&mut reply).await?;
if reply != [0x05, 0x00] {
anyhow::bail!("SOCKS5 auth not accepted");
}
let (host, port) = split_host_port(target).ok_or_else(|| anyhow::anyhow!("invalid target"))?;
let mut req = Vec::new();
req.extend_from_slice(&[0x05, 0x01, 0x00]);
if let Ok(ip) = host.parse::<std::net::IpAddr>() {
match ip {
std::net::IpAddr::V4(v4) => {
req.push(0x01);
req.extend_from_slice(&v4.octets());
}
std::net::IpAddr::V6(v6) => {
req.push(0x04);
req.extend_from_slice(&v6.octets());
}
}
} else {
req.push(0x03);
req.push(host.len() as u8);
req.extend_from_slice(host.as_bytes());
}
req.extend_from_slice(&port.to_be_bytes());
stream.write_all(&req).await?;
let mut header = [0u8; 4];
stream.read_exact(&mut header).await?;
if header[1] != 0x00 {
anyhow::bail!("SOCKS5 connect failed: 0x{:02x}", header[1]);
}
let addr_len = match header[3] {
0x01 => 4,
0x04 => 16,
0x03 => {
let mut len = [0u8; 1];
stream.read_exact(&mut len).await?;
len[0] as usize
}
_ => 0,
};
if addr_len > 0 {
let mut skip = vec![0u8; addr_len + 2];
stream.read_exact(&mut skip).await?;
}
Ok(stream)
}
async fn connect_via_http(proxy_addr: &str, target: &str) -> Result<TcpStream> {
use tokio::io::{AsyncReadExt, AsyncWriteExt};
let mut stream = TcpStream::connect(proxy_addr).await?;
let request = format!("CONNECT {target} HTTP/1.1\r\nHost: {target}\r\n\r\n");
stream.write_all(request.as_bytes()).await?;
let mut buf = vec![0u8; 1024];
let n = stream.read(&mut buf).await?;
let response = String::from_utf8_lossy(&buf[..n]);
if !response.starts_with("HTTP/1.1 200") && !response.starts_with("HTTP/1.0 200") {
anyhow::bail!("HTTP CONNECT failed: {response}");
}
Ok(stream)
}
pub enum UdpProxySocket {
Direct(std::sync::Arc<tokio::net::UdpSocket>),
Socks5 {
tcp_keepalive: TcpStream,
udp_sock: std::sync::Arc<tokio::net::UdpSocket>,
proxy_bnd_addr: std::net::SocketAddr,
},
}
impl UdpProxySocket {
pub async fn send_to(&self, data: &[u8], target: &str) -> Result<usize> {
match self {
UdpProxySocket::Direct(sock) => {
sock.send_to(data, target).await.map_err(Into::into)
}
UdpProxySocket::Socks5 { udp_sock, proxy_bnd_addr, .. } => {
let (host, port) = split_host_port(target).ok_or_else(|| anyhow::anyhow!("invalid target"))?;
let mut req = Vec::with_capacity(10 + host.len() + data.len());
req.extend_from_slice(&[0x00, 0x00, 0x00]); // RSV, FRAG
if let Ok(ip) = host.parse::<std::net::IpAddr>() {
match ip {
std::net::IpAddr::V4(v4) => {
req.push(0x01);
req.extend_from_slice(&v4.octets());
}
std::net::IpAddr::V6(v6) => {
req.push(0x04);
req.extend_from_slice(&v6.octets());
}
}
} else {
req.push(0x03);
req.push(host.len() as u8);
req.extend_from_slice(host.as_bytes());
}
req.extend_from_slice(&port.to_be_bytes());
req.extend_from_slice(data);
udp_sock.send_to(&req, proxy_bnd_addr).await.map_err(Into::into)
}
}
}
pub async fn recv_from(&self, buf: &mut [u8]) -> Result<(usize, String)> {
match self {
UdpProxySocket::Direct(sock) => {
let (len, addr) = sock.recv_from(buf).await?;
Ok((len, addr.to_string()))
}
UdpProxySocket::Socks5 { udp_sock, proxy_bnd_addr, .. } => {
loop {
let (len, src) = udp_sock.recv_from(buf).await?;
if src != *proxy_bnd_addr {
continue; // ignore rogue packets
}
if len < 10 {
continue;
}
if buf[0] != 0x00 || buf[1] != 0x00 {
continue; // Invalid RSV
}
let frag = buf[2];
if frag != 0x00 {
continue; // Fragments not supported
}
let atyp = buf[3];
let (addr_str, port, payload_offset) = match atyp {
0x01 if len >= 10 => {
let ip = std::net::Ipv4Addr::new(buf[4], buf[5], buf[6], buf[7]);
let port = u16::from_be_bytes([buf[8], buf[9]]);
(ip.to_string(), port, 10)
}
0x04 if len >= 22 => {
let mut ip_bytes = [0u8; 16];
ip_bytes.copy_from_slice(&buf[4..20]);
let ip = std::net::Ipv6Addr::from(ip_bytes);
let port = u16::from_be_bytes([buf[20], buf[21]]);
(ip.to_string(), port, 22)
}
0x03 if len >= 5 => {
let domain_len = buf[4] as usize;
if len >= 5 + domain_len + 2 {
let domain = String::from_utf8_lossy(&buf[5..5 + domain_len]).into_owned();
let port = u16::from_be_bytes([buf[5 + domain_len], buf[5 + domain_len + 1]]);
(domain, port, 5 + domain_len + 2)
} else {
continue;
}
}
_ => continue,
};
let target = format!("{}:{}", addr_str, port);
let payload_len = len - payload_offset;
// Move payload to start of buffer
buf.copy_within(payload_offset..len, 0);
return Ok((payload_len, target));
}
}
}
}
}
pub async fn connect_udp_target(
target: &str,
outbound: Option<&OutboundConfig>,
debug: bool,
server_udp: std::sync::Arc<tokio::net::UdpSocket>,
) -> Result<UdpProxySocket> {
if let Some(outbound) = outbound {
if outbound.enabled {
let action = select_outbound_action(target, "udp", outbound, debug).await;
if action == OutboundAction::Block {
return Err(anyhow::anyhow!("blocked by outbound udp rule: {}", target));
}
if action == OutboundAction::Proxy {
let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
if outbound.protocol == "socks5" {
return connect_udp_via_socks5(&proxy_addr, server_udp).await;
}
// HTTP CONNECT does not support UDP. Fallback to direct.
}
}
}
Ok(UdpProxySocket::Direct(server_udp))
}
pub async fn connect_udp_via_socks5(
proxy_addr: &str,
server_udp: std::sync::Arc<tokio::net::UdpSocket>,
) -> Result<UdpProxySocket> {
use tokio::io::{AsyncReadExt, AsyncWriteExt};
let mut stream = TcpStream::connect(proxy_addr).await?;
stream.write_all(&[0x05, 0x01, 0x00]).await?;
let mut reply = [0u8; 2];
stream.read_exact(&mut reply).await?;
if reply != [0x05, 0x00] {
anyhow::bail!("SOCKS5 auth not accepted");
}
// Send UDP Associate request
let local_addr = server_udp.local_addr()?;
let mut req = vec![0x05, 0x03, 0x00];
match local_addr.ip() {
std::net::IpAddr::V4(v4) => {
req.push(0x01);
req.extend_from_slice(&v4.octets());
}
std::net::IpAddr::V6(v6) => {
req.push(0x04);
req.extend_from_slice(&v6.octets());
}
}
req.extend_from_slice(&local_addr.port().to_be_bytes());
stream.write_all(&req).await?;
let mut header = [0u8; 4];
stream.read_exact(&mut header).await?;
if header[1] != 0x00 {
anyhow::bail!("SOCKS5 UDP associate failed: 0x{:02x}", header[1]);
}
let bnd_addr = match header[3] {
0x01 => {
let mut ip = [0u8; 4];
stream.read_exact(&mut ip).await?;
std::net::IpAddr::V4(ip.into())
}
0x04 => {
let mut ip = [0u8; 16];
stream.read_exact(&mut ip).await?;
std::net::IpAddr::V6(ip.into())
}
0x03 => {
let mut len = [0u8; 1];
stream.read_exact(&mut len).await?;
let mut domain = vec![0u8; len[0] as usize];
stream.read_exact(&mut domain).await?;
let domain_str = String::from_utf8_lossy(&domain);
// SOCKS5 specifies BND.ADDR. If it's a domain, we must resolve it.
// Typically proxies return an IP address for BND.ADDR.
let resolved = tokio::net::lookup_host(format!("{}:0", domain_str))
.await?
.next()
.ok_or_else(|| anyhow::anyhow!("could not resolve proxy BND.ADDR"))?;
resolved.ip()
}
_ => anyhow::bail!("unknown address type in SOCKS5 reply"),
};
let mut port_bytes = [0u8; 2];
stream.read_exact(&mut port_bytes).await?;
let bnd_port = u16::from_be_bytes(port_bytes);
let proxy_bnd_addr = std::net::SocketAddr::new(bnd_addr, bnd_port);
Ok(UdpProxySocket::Socks5 {
tcp_keepalive: stream,
udp_sock: server_udp,
proxy_bnd_addr,
})
}
// ── CIDR utilities ───────────────────────────────────────────────────────────
enum Cidr {
V4(u32, u8),
V6(u128, u8),
}
impl Cidr {
fn contains(&self, ip: &std::net::IpAddr) -> bool {
match (self, ip) {
(Cidr::V4(net, bits), std::net::IpAddr::V4(addr)) => {
let mask = if *bits == 0 { 0 } else { u32::MAX << (32 - bits) };
let ip = u32::from_be_bytes(addr.octets());
(ip & mask) == (*net & mask)
}
(Cidr::V6(net, bits), std::net::IpAddr::V6(addr)) => {
let mask = if *bits == 0 { 0 } else { u128::MAX << (128 - bits) };
let ip = u128::from_be_bytes(addr.octets());
(ip & mask) == (*net & mask)
}
_ => false,
}
}
}
fn parse_cidr(value: &str) -> Option<Cidr> {
let value = value.trim();
if value.is_empty() {
return None;
}
if let Some((addr_str, bits_str)) = value.split_once('/') {
let bits: u8 = bits_str.parse().ok()?;
if let Ok(addr) = addr_str.parse::<std::net::IpAddr>() {
return match addr {
std::net::IpAddr::V4(v4) => Some(Cidr::V4(u32::from_be_bytes(v4.octets()), bits.min(32))),
std::net::IpAddr::V6(v6) => Some(Cidr::V6(u128::from_be_bytes(v6.octets()), bits.min(128))),
};
}
}
if let Ok(addr) = value.parse::<std::net::IpAddr>() {
return match addr {
std::net::IpAddr::V4(v4) => Some(Cidr::V4(u32::from_be_bytes(v4.octets()), 32)),
std::net::IpAddr::V6(v6) => Some(Cidr::V6(u128::from_be_bytes(v6.octets()), 128)),
};
}
None
}
pub fn split_host_port(target: &str) -> Option<(String, u16)> {
if let Some((host, port)) = target.rsplit_once(':') {
if host.starts_with('[') && host.ends_with(']') {
let host = host.trim_start_matches('[').trim_end_matches(']').to_string();
let port = port.parse().ok()?;
return Some((host, port));
}
if host.contains(':') {
return None;
}
let port = port.parse().ok()?;
return Some((host.to_string(), port));
}
None
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_split_host_port() {
assert_eq!(split_host_port("example.com:443"), Some(("example.com".to_string(), 443)));
assert_eq!(split_host_port("127.0.0.1:80"), Some(("127.0.0.1".to_string(), 80)));
assert_eq!(split_host_port("[::1]:8080"), Some(("::1".to_string(), 8080)));
assert_eq!(split_host_port("noport"), None);
assert_eq!(split_host_port("::1:8080"), None); // ambiguous IPv6 without brackets
}
#[test]
fn test_parse_cidr_v4() {
let cidr = parse_cidr("10.0.0.0/8").unwrap();
assert!(cidr.contains(&"10.1.2.3".parse().unwrap()));
assert!(cidr.contains(&"10.255.255.255".parse().unwrap()));
assert!(!cidr.contains(&"11.0.0.1".parse().unwrap()));
}
#[test]
fn test_parse_cidr_v4_exact() {
let cidr = parse_cidr("192.168.1.1").unwrap();
assert!(cidr.contains(&"192.168.1.1".parse().unwrap()));
assert!(!cidr.contains(&"192.168.1.2".parse().unwrap()));
}
#[test]
fn test_parse_cidr_v6() {
let cidr = parse_cidr("::1/128").unwrap();
assert!(cidr.contains(&"::1".parse().unwrap()));
assert!(!cidr.contains(&"::2".parse().unwrap()));
}
#[test]
fn test_parse_cidr_invalid() {
assert!(parse_cidr("").is_none());
assert!(parse_cidr("not-an-ip/24").is_none());
}
#[test]
fn test_match_domain_rule() {
assert!(match_domain_rule("example.com", &[".example.com".to_string()]));
assert!(match_domain_rule("sub.example.com", &[".example.com".to_string()]));
assert!(!match_domain_rule("notexample.com", &[".example.com".to_string()]));
assert!(match_domain_rule("test.onion", &[".onion".to_string()]));
assert!(!match_domain_rule("onion.com", &[".onion".to_string()]));
}
#[test]
fn test_match_domain_rule_exact() {
// Without dot prefix, the rule matches both exact and subdomains
// because the implementation treats "example.com" as a suffix match
assert!(match_domain_rule("example.com", &["example.com".to_string()]));
assert!(match_domain_rule("sub.example.com", &["example.com".to_string()]));
}
#[test]
fn test_match_domain_rule_empty() {
assert!(!match_domain_rule("example.com", &[]));
}
}