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No commits in common. "df1a14d15c181dd9a47e7e74437b073b26e33210" and "365b4ccbf5dfad1eaf0b013523c3fb62ae66ea4f" have entirely different histories.

8 changed files with 355 additions and 486 deletions

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@ -2,5 +2,5 @@
"target_version": "0.4.3", "target_version": "0.4.3",
"branch": "beta", "branch": "beta",
"alpha_iteration": 0, "alpha_iteration": 0,
"beta_iteration": 2 "beta_iteration": 1
} }

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@ -20,15 +20,9 @@
// Адрес следующего узла в цепочке UDP // Адрес следующего узла в цепочке UDP
"upstream_udp": "TARGET_SERVER_IP:50000", "upstream_udp": "TARGET_SERVER_IP:50000",
// URL API конечного (целевого) сервера для синхронизации access_keys. // URL API конечного (целевого) сервера для синхронизации access_keys
// Должен быть доступен с этого relay-сервера (можно через SSH-туннель). // Должен быть доступен с этого relay-сервера (можно через SSH-туннель)
// "upstream_api_url": "http://TARGET_SERVER_IP:9090",
// ВАЖНО: URL обязан включать секретный путь панели (api.webpath целевого
// сервера). Management API смонтирован ВНУТРИ этого пути именно он скрывает
// панель от сканеров, поэтому голый host:port попадает в несуществующий
// маршрут, и синхронизация падает с 404 ещё до проверки токена.
// Это тот же адрес, по которому вы открываете веб-панель.
"upstream_api_url": "http://TARGET_SERVER_IP:9090/TARGET_SERVER_WEBPATH",
// Bearer-токен для доступа к API целевого сервера // Bearer-токен для доступа к API целевого сервера
// Должен совпадать с api.token в конфиге target-сервера // Должен совпадать с api.token в конфиге target-сервера

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@ -418,22 +418,19 @@ pub struct RelayServerConfig {
pub upstream_tcp: String, pub upstream_tcp: String,
/// Upstream address for UDP traffic /// Upstream address for UDP traffic
pub upstream_udp: String, pub upstream_udp: String,
// ── Deprecated ────────────────────────────────────────────────────────── /// Target server's API URL, for key sync
// The relay used to authenticate clients itself and pulled the access-key
// list from the target server's management API to do it. It no longer does:
// sessions are authenticated end-to-end by the target server, and a relay
// that re-checks credentials only adds a weaker second gate plus a copy of
// the key list on a machine that does not need one. These are kept solely
// so existing relay configs still parse; they are ignored.
#[serde(default)]
pub upstream_api_url: String, pub upstream_api_url: String,
/// Bearer token for the target server's API
#[serde(default)] #[serde(default)]
pub upstream_api_token: String, pub upstream_api_token: String,
#[serde(default)] /// Key sync interval in seconds (default 30)
#[serde(default = "default_sync_interval")]
pub sync_interval_secs: u64, pub sync_interval_secs: u64,
pub debug: Option<bool>, pub debug: Option<bool>,
} }
fn default_sync_interval() -> u64 { 30 }
/// Supports both a single string "0.0.0.0:50000" and an array /// Supports both a single string "0.0.0.0:50000" and an array
/// ["0.0.0.0:50000", "[::]:50000"]. /// ["0.0.0.0:50000", "[::]:50000"].
#[derive(Debug, Deserialize, Serialize, Clone)] #[derive(Debug, Deserialize, Serialize, Clone)]

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@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
# In Windows, build-name is used as the major, minor, and patch parts # In Windows, build-name is used as the major, minor, and patch parts
# of the product and file versions while build-number is used as the build suffix. # of the product and file versions while build-number is used as the build suffix.
version: 0.4.3+27 version: 0.4.3+26
environment: environment:
sdk: ^3.11.4 sdk: ^3.11.4

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@ -48,23 +48,10 @@ pub async fn connect_target(
} }
if action == OutboundAction::Proxy { if action == OutboundAction::Proxy {
let proxy_addr = format!("{}:{}", outbound.address, outbound.port); let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
// Case-insensitive: a config saying "SOCKS5" means the same thing return match outbound.protocol.as_str() {
// as "socks5", and silently treating it as unknown is a trap.
return match outbound.protocol.to_ascii_lowercase().as_str() {
"socks5" => connect_via_socks5(&proxy_addr, target).await, "socks5" => connect_via_socks5(&proxy_addr, target).await,
"http" => connect_via_http(&proxy_addr, target).await, "http" => connect_via_http(&proxy_addr, target).await,
// FAIL CLOSED. This used to fall through to a direct _ => connect_direct(target, connect_timeout).await,
// connection, so any unrecognised protocol string — a typo,
// a case difference, an empty value — silently sent ALL TCP
// straight out of the server while the operator believed it
// was proxied. Combined with the same bug on the UDP path,
// that is how one session ends up presenting two different
// exit addresses to the remote site.
other => Err(anyhow::anyhow!(
"outbound.protocol is \"{other}\", which is not a supported proxy type \
(expected \"socks5\" or \"http\"); refusing to connect to {target} \
directly, because the rules asked for the proxy"
)),
}; };
} }
} }
@ -383,22 +370,10 @@ pub async fn connect_udp_target(
} }
if action == OutboundAction::Proxy { if action == OutboundAction::Proxy {
let proxy_addr = format!("{}:{}", outbound.address, outbound.port); let proxy_addr = format!("{}:{}", outbound.address, outbound.port);
if outbound.protocol.eq_ignore_ascii_case("socks5") { if outbound.protocol == "socks5" {
return connect_udp_via_socks5(&proxy_addr, server_udp).await; return connect_udp_via_socks5(&proxy_addr, server_udp).await;
} }
// FAIL CLOSED. HTTP CONNECT genuinely cannot carry UDP — but the // HTTP CONNECT does not support UDP. Fallback to direct.
// answer to that is not to send the datagrams in the clear. The
// previous "fallback to direct" honoured a Proxy rule by
// egressing from the server's own address, so with an HTTP
// upstream every UDP flow (QUIC, DNS) leaked while TCP stayed
// proxied, presenting two exit IPs to the same remote site.
return Err(anyhow::anyhow!(
"outbound rules route UDP to {target} through the proxy, but the upstream \
protocol is \"{}\", which cannot carry UDP. Refusing to send directly. \
Use a socks5 upstream, or add an explicit udp rule with action \"direct\" \
or \"block\" so the intent is recorded in the config.",
outbound.protocol
));
} }
} }
} }

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@ -1,460 +1,403 @@
//! Transparent relay node. //! Authenticated Relay Node
//! //!
//! Forwards traffic to a fixed upstream OSTP server: //! Принимает входящие UDP/TCP (UoT) соединения от клиентов,
//! валидирует HMAC-подпись клиента, используя ключи синхронизированные с upstream-сервера,
//! и слепо пробрасывает авторизованный трафик к целевому upstream-серверу.
//! //!
//! Client -> [Relay] -> [Target server] //! Архитектура цепочек:
//! //! Клиент -> [Relay 1] -> [Relay 2] -> ... -> [Target Server]
//! ## Why this performs no authentication of its own //! Каждый Relay скачивает access_keys напрямую с Target Server API.
//!
//! The previous design had the relay authenticate clients itself, with an
//! HMAC handshake and a background job that pulled the access-key list from the
//! target server's management API. That was wrong on two counts.
//!
//! It did not work: no OSTP client has ever produced those credentials. The TCP
//! path expected an HTTP request (`GET /stream` with an `Authorization: Bearer`
//! header) and the UDP path expected a `timestamp || HMAC` preamble, while the
//! client sends junk frames followed by length-prefixed OSTP frames, and an
//! obfuscated Noise handshake, respectively. Every connection was rejected.
//!
//! It was also weak where it did apply: the HMAC covered only an 8-byte
//! timestamp, so a captured signature was a bearer token that anyone could
//! replay from any address for the length of the clock-skew window. And the
//! HTTP handshake was a plaintext `GET /stream` on the wire, a greppable
//! signature in a protocol whose entire premise is that no byte is
//! recognisable.
//!
//! Authentication belongs where it is cryptographically meaningful: the target
//! server already authenticates every session end-to-end via Noise with a PSK
//! derived from the access key, and silently drops anything that fails. A relay
//! that re-checks credentials adds a second, weaker gate and a copy of the key
//! list on a machine that has no need for it. So this relay makes no security
//! decisions at all — it is a pipe, and says so.
//!
//! What it does need is protection against being used as a resource sink, which
//! is what the session cap and admission rate limit below are for. It forwards
//! only to one fixed upstream and returns replies only to the sender, so it is
//! not a reflector: the amplification factor is one.
use anyhow::{Context, Result}; use anyhow::Result;
use bytes::Bytes;
use hmac::{Hmac, Mac};
use sha2::Sha256;
use std::collections::HashMap; use std::collections::HashMap;
use std::net::SocketAddr; use std::net::SocketAddr;
use std::sync::Arc; use std::sync::{Arc, RwLock};
use std::time::{Duration, Instant}; use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
use tokio::io::{AsyncReadExt, AsyncWriteExt};
use tokio::net::{TcpListener, TcpStream, UdpSocket}; use tokio::net::{TcpListener, TcpStream, UdpSocket};
use tokio::sync::Mutex; use tokio::sync::Mutex;
/// Configuration for a relay node. /// Конфигурация Relay-узла.
#[derive(Debug, Clone)] #[derive(Debug, Clone)]
pub struct RelayConfig { pub struct RelayConfig {
/// Address(es) to accept client traffic on (UDP and TCP both bind here). /// Адрес(а) для прослушивания входящих соединений (UDP + TCP).
pub listen_addrs: Vec<String>, pub listen_addrs: Vec<String>,
/// Upstream target for TCP (UoT) traffic. /// Адрес upstream TCP для пересылки (обычно тот же порт, что и у target-сервера).
pub upstream_tcp: String, pub upstream_tcp: String,
/// Upstream target for UDP traffic. /// Адрес upstream UDP.
pub upstream_udp: String, pub upstream_udp: String,
/// URL API target-сервера для получения access_keys.
/// Пример: "http://127.0.0.1:9090"
pub upstream_api_url: String,
/// Bearer-токен для аутентификации на API target-сервера.
pub upstream_api_token: String,
/// Интервал синхронизации ключей (секунды).
pub sync_interval_secs: u64,
} }
/// Maximum concurrent UDP client sessions. Each holds one upstream socket and type SharedKeys = Arc<RwLock<Vec<String>>>;
/// one reader task, so this bounds both file descriptors and tasks.
const MAX_UDP_SESSIONS: usize = 4096;
/// A UDP session with no traffic for this long is reclaimed. Mobile NAT
/// bindings are typically shorter-lived than this, so it is generous enough not
/// to break roaming clients.
const UDP_SESSION_IDLE: Duration = Duration::from_secs(120);
/// Maximum concurrent relayed TCP connections.
const MAX_TCP_CONNECTIONS: usize = 4096;
/// Sustained rate (and burst ceiling) for admitting NEW sessions, per second.
/// Established sessions are never rate limited; this only bounds how fast an
/// unknown source can cause state to be allocated.
const NEW_SESSION_RATE: f64 = 200.0;
/// How long to wait for the upstream TCP connection before giving up.
const UPSTREAM_CONNECT_TIMEOUT: Duration = Duration::from_secs(8);
/// Token bucket bounding how fast new sessions may be created. /// Точка входа Relay-узла.
struct AdmissionLimiter {
tokens: f64,
last_refill: Instant,
}
impl AdmissionLimiter {
fn new() -> Self {
Self { tokens: NEW_SESSION_RATE, last_refill: Instant::now() }
}
/// Consume one admission slot, or report that the caller should drop.
fn try_admit(&mut self) -> bool {
let now = Instant::now();
let elapsed = now.duration_since(self.last_refill).as_secs_f64();
self.last_refill = now;
self.tokens = (self.tokens + elapsed * NEW_SESSION_RATE).min(NEW_SESSION_RATE);
if self.tokens >= 1.0 {
self.tokens -= 1.0;
true
} else {
false
}
}
}
/// Entry point.
pub async fn run_relay_node(cfg: RelayConfig) -> Result<()> { pub async fn run_relay_node(cfg: RelayConfig) -> Result<()> {
let udp_cfg = cfg.clone(); let shared_keys: SharedKeys = Arc::new(RwLock::new(Vec::new()));
// Первоначальная синхронизация ключей
if let Err(e) = sync_keys(&cfg, &shared_keys).await {
tracing::warn!("Relay: initial key sync failed: {}. Will retry.", e);
} else {
let count = shared_keys.read().unwrap_or_else(|e| e.into_inner()).len();
tracing::info!("Relay: synced {} access key(s) from upstream API", count);
}
// Фоновый синхронизатор ключей
let cfg_clone = cfg.clone();
let keys_clone = shared_keys.clone();
tokio::spawn(async move { tokio::spawn(async move {
if let Err(e) = run_udp_relay(udp_cfg).await { loop {
tracing::error!("Relay UDP loop error: {e}"); tokio::time::sleep(Duration::from_secs(cfg_clone.sync_interval_secs)).await;
match sync_keys(&cfg_clone, &keys_clone).await {
Ok(count) => tracing::debug!("Relay: refreshed {} access key(s)", count),
Err(e) => tracing::warn!("Relay: key sync error: {}", e),
}
} }
}); });
run_tcp_relay(cfg).await // Запуск UDP relay
{
let cfg_udp = cfg.clone();
let keys_udp = shared_keys.clone();
tokio::spawn(async move {
if let Err(e) = run_udp_relay(cfg_udp, keys_udp).await {
tracing::error!("Relay UDP loop error: {}", e);
}
});
}
// Запуск TCP (UoT) relay
run_tcp_relay(cfg, shared_keys).await
} }
// ── UDP ────────────────────────────────────────────────────────────────────── /// Синхронизация access_keys с upstream API.
async fn sync_keys(cfg: &RelayConfig, shared_keys: &SharedKeys) -> Result<usize> {
let url = format!("{}/api/users", cfg.upstream_api_url.trim_end_matches('/'));
struct UdpSession { let client = reqwest::Client::builder()
upstream: Arc<UdpSocket>, .timeout(Duration::from_secs(10))
last_seen: Instant, .build()?;
let mut req = client.get(&url);
if !cfg.upstream_api_token.is_empty() {
req = req.header("Authorization", format!("Bearer {}", cfg.upstream_api_token));
}
let resp = req.send().await?;
if !resp.status().is_success() {
anyhow::bail!("API returned HTTP {}", resp.status());
}
#[derive(serde::Deserialize)]
struct UserStatsSnapshot {
access_key: String,
}
#[derive(serde::Deserialize)]
struct ApiResponse {
ok: bool,
data: Option<Vec<UserStatsSnapshot>>,
}
let body: ApiResponse = resp.json().await?;
if !body.ok {
anyhow::bail!("API returned error ok=false");
}
let keys: Vec<String> = body.data.unwrap_or_default().into_iter().map(|u| u.access_key).collect();
let count = keys.len();
{
let mut lock = shared_keys.write().unwrap();
*lock = keys;
}
Ok(count)
} }
async fn run_udp_relay(cfg: RelayConfig) -> Result<()> { /// Проверяет HMAC-подпись клиента по набору ключей.
// client address -> the upstream socket carrying that client's flow /// Возвращает true если хотя бы один ключ подходит.
let sessions: Arc<Mutex<HashMap<SocketAddr, UdpSession>>> = fn verify_hmac(ts_bytes: &[u8; 8], provided_mac: &[u8], keys: &[String]) -> bool {
let client_ts = u64::from_be_bytes(*ts_bytes);
let now = SystemTime::now()
.duration_since(UNIX_EPOCH)
.unwrap()
.as_secs();
// Защита от replay: ±60 секунд
if client_ts > now + 30 || client_ts < now.saturating_sub(60) {
return false;
}
for key in keys {
if let Ok(mut mac) = Hmac::<Sha256>::new_from_slice(key.as_bytes()) {
mac.update(ts_bytes);
if mac.verify_slice(provided_mac).is_ok() {
return true;
}
}
}
false
}
// ── UDP Relay ────────────────────────────────────────────────────────────────
async fn run_udp_relay(cfg: RelayConfig, shared_keys: SharedKeys) -> Result<()> {
// NAT-таблица: client_addr -> (upstream_socket, last_seen)
let nat_table: Arc<Mutex<HashMap<SocketAddr, (Arc<UdpSocket>, Instant)>>> =
Arc::new(Mutex::new(HashMap::new())); Arc::new(Mutex::new(HashMap::new()));
let limiter = Arc::new(Mutex::new(AdmissionLimiter::new()));
for bind_addr in &cfg.listen_addrs { for bind_addr in &cfg.listen_addrs {
let sock = Arc::new( let sock = UdpSocket::bind(bind_addr).await?;
UdpSocket::bind(bind_addr) tracing::info!("Relay UDP listening on {}", bind_addr);
.await let sock = Arc::new(sock);
.with_context(|| format!("relay: failed to bind UDP on {bind_addr}"))?, let upstream_udp = cfg.upstream_udp.clone();
); let keys = shared_keys.clone();
tracing::info!("Relay UDP listening on {bind_addr} -> {}", cfg.upstream_udp); let nat = nat_table.clone();
let upstream_addr = cfg.upstream_udp.clone();
let sessions = sessions.clone();
let limiter = limiter.clone();
tokio::spawn(async move { tokio::spawn(async move {
let mut buf = vec![0u8; 65535]; let mut buf = vec![0u8; 65535];
loop { loop {
let (len, peer) = match sock.recv_from(&mut buf).await { let (n, peer) = match sock.recv_from(&mut buf).await {
Ok(v) => v, Ok(v) => v,
Err(e) => { Err(_) => continue,
tracing::warn!("Relay UDP recv error: {e}");
continue;
}
}; };
// Fast path: an established session just forwards. let packet = Bytes::copy_from_slice(&buf[..n]);
// Быстрая проверка: первый UDP-пакет от нового клиента содержит Noise handshake.
// Мы берём из него первые 8 байт как timestamp + 32 байта MAC.
// Если пакет достаточно длинный, проверяем подпись.
// Для уже авторизованных клиентов (есть в NAT) — пропускаем проверку.
{ {
let mut map = sessions.lock().await; let nat_lock = nat.lock().await;
if let Some(session) = map.get_mut(&peer) { if !nat_lock.contains_key(&peer) {
session.last_seen = Instant::now(); drop(nat_lock);
let upstream = session.upstream.clone();
drop(map); // Пакет должен быть >= 40 байт (8 ts + 32 hmac) для первичной проверки
let _ = upstream.send(&buf[..len]).await; if packet.len() < 40 {
continue; tracing::debug!("Relay UDP: dropping short packet from {}", peer);
continue;
}
let ts_bytes: [u8; 8] = packet[0..8].try_into().unwrap();
let provided_mac = &packet[8..40];
let keys_guard = keys.read().unwrap_or_else(|e| e.into_inner());
if !verify_hmac(&ts_bytes, provided_mac, &keys_guard) {
tracing::debug!("Relay UDP: unauthorized probe from {}, dropped", peer);
continue;
}
tracing::debug!("Relay UDP: authorized new client {}", peer);
} }
} }
// New client: bounded by both a hard cap and an admission rate, // Находим или создаём upstream socket для этого клиента
// so a flood of spoofed sources cannot exhaust sockets or tasks. let upstream_sock = {
{ let mut nat_lock = nat.lock().await;
let map = sessions.lock().await; if let Some(entry) = nat_lock.get_mut(&peer) {
if map.len() >= MAX_UDP_SESSIONS { entry.1 = Instant::now();
continue; entry.0.clone()
} } else {
} // Новый upstream socket для этого клиента
if !limiter.lock().await.try_admit() { let usock = match UdpSocket::bind("0.0.0.0:0").await {
continue; Ok(s) => Arc::new(s),
} Err(e) => {
tracing::warn!("Relay UDP: failed to bind upstream socket: {}", e);
continue;
}
};
if usock.connect(&upstream_udp).await.is_err() {
tracing::warn!("Relay UDP: failed to connect to upstream {}", upstream_udp);
continue;
}
let upstream = match new_upstream_socket(&upstream_addr).await { nat_lock.insert(peer, (usock.clone(), Instant::now()));
Ok(s) => s,
Err(e) => {
tracing::warn!("Relay UDP: cannot reach upstream {upstream_addr}: {e}");
continue;
}
};
sessions.lock().await.insert( // Задача: читаем ответы от upstream и отправляем клиенту
peer, let usock_rx = usock.clone();
UdpSession { upstream: upstream.clone(), last_seen: Instant::now() }, let client_sock = sock.clone();
); let peer_addr = peer;
tokio::spawn(async move {
// Reverse direction for this client. let mut rbuf = vec![0u8; 65535];
let back_sock = sock.clone(); loop {
let sessions_rx = sessions.clone(); match usock_rx.recv(&mut rbuf).await {
tokio::spawn(async move { Ok(n) => {
let mut rbuf = vec![0u8; 65535]; let _ = client_sock.send_to(&rbuf[..n], peer_addr).await;
loop { }
match upstream.recv(&mut rbuf).await { Err(_) => break,
Ok(n) => {
if back_sock.send_to(&rbuf[..n], peer).await.is_err() {
break;
}
if let Some(s) = sessions_rx.lock().await.get_mut(&peer) {
s.last_seen = Instant::now();
} }
} }
Err(_) => break, });
}
}
sessions_rx.lock().await.remove(&peer);
});
let _ = sessions usock
.lock() }
.await };
.get(&peer)
.map(|s| s.upstream.clone()) // Пересылаем пакет в upstream
.unwrap() let _ = upstream_sock.send(&packet).await;
.send(&buf[..len])
.await;
} }
}); });
} }
// Reclaim idle sessions. Dropping the entry closes the upstream socket, // Периодически чистим устаревшие NAT записи (timeout 120 сек)
// which ends that session's reader task.
loop { loop {
tokio::time::sleep(Duration::from_secs(30)).await; tokio::time::sleep(Duration::from_secs(30)).await;
let mut nat_lock = nat_table.lock().await;
let now = Instant::now(); let now = Instant::now();
let mut map = sessions.lock().await; nat_lock.retain(|_, (_, last)| now.duration_since(*last) < Duration::from_secs(120));
let before = map.len();
map.retain(|_, s| now.duration_since(s.last_seen) < UDP_SESSION_IDLE);
let reclaimed = before - map.len();
if reclaimed > 0 {
tracing::debug!("Relay UDP: reclaimed {reclaimed} idle session(s), {} active", map.len());
}
} }
} }
/// One upstream socket per client, `connect`ed so replies can be read with // ── TCP (UoT) Relay ──────────────────────────────────────────────────────────
/// `recv` and cannot come from anywhere else.
async fn new_upstream_socket(upstream: &str) -> Result<Arc<UdpSocket>> {
// Resolve first, then bind the SAME address family. Binding "[::]:0" and
// connecting to an IPv4 upstream fails anywhere IPV6_V6ONLY defaults on
// (Windows, and many Linux configurations) — which is every deployment with
// an IPv4 target server, i.e. the common case.
let addr: SocketAddr = tokio::net::lookup_host(upstream)
.await
.with_context(|| format!("resolve upstream {upstream}"))?
.next()
.ok_or_else(|| anyhow::anyhow!("upstream {upstream} resolved to no addresses"))?;
let bind: SocketAddr = if addr.is_ipv6() {
"[::]:0".parse().expect("valid literal")
} else {
"0.0.0.0:0".parse().expect("valid literal")
};
let sock = UdpSocket::bind(bind).await?;
sock.connect(addr)
.await
.with_context(|| format!("connect to upstream {addr}"))?;
Ok(Arc::new(sock))
}
// ── TCP (UoT) ────────────────────────────────────────────────────────────────
async fn run_tcp_relay(cfg: RelayConfig) -> Result<()> {
let live = Arc::new(std::sync::atomic::AtomicUsize::new(0));
async fn run_tcp_relay(cfg: RelayConfig, shared_keys: SharedKeys) -> Result<()> {
for bind_addr in &cfg.listen_addrs { for bind_addr in &cfg.listen_addrs {
let listener = TcpListener::bind(bind_addr) let listener = TcpListener::bind(bind_addr).await?;
.await tracing::info!("Relay TCP (UoT) listening on {}", bind_addr);
.with_context(|| format!("relay: failed to bind TCP on {bind_addr}"))?;
tracing::info!("Relay TCP (UoT) listening on {bind_addr} -> {}", cfg.upstream_tcp);
let upstream = cfg.upstream_tcp.clone(); let upstream_tcp = cfg.upstream_tcp.clone();
let live = live.clone(); let keys = shared_keys.clone();
tokio::spawn(async move { tokio::spawn(async move {
loop { loop {
let (client, peer) = match listener.accept().await { let (stream, peer_addr) = match listener.accept().await {
Ok(v) => v, Ok(v) => v,
Err(e) => { Err(e) => {
tracing::warn!("Relay TCP accept error: {e}"); tracing::warn!("Relay TCP accept error: {}", e);
continue; continue;
} }
}; };
use std::sync::atomic::Ordering; let upstream = upstream_tcp.clone();
if live.load(Ordering::Relaxed) >= MAX_TCP_CONNECTIONS { let keys_clone = keys.clone();
// Close immediately rather than queueing unbounded work.
drop(client);
continue;
}
live.fetch_add(1, Ordering::Relaxed);
let upstream = upstream.clone();
let live = live.clone();
tokio::spawn(async move { tokio::spawn(async move {
if let Err(e) = splice_tcp(client, &upstream).await { if let Err(e) = handle_tcp_client(stream, peer_addr, upstream, keys_clone).await {
tracing::debug!("Relay TCP {peer} closed: {e}"); tracing::debug!("Relay TCP client {} closed: {}", peer_addr, e);
} }
live.fetch_sub(1, Ordering::Relaxed);
}); });
} }
}); });
} }
// Держим поток живым
futures_util::future::pending::<()>().await; futures_util::future::pending::<()>().await;
Ok(()) Ok(())
} }
/// Splice a client connection to the upstream, byte for byte. /// Обработка одного TCP (UoT) соединения.
/// ///
/// Nothing is parsed or rewritten: the relay must stay agnostic to the payload, /// Алгоритм:
/// both because the payload is an opaque encrypted stream and because any /// 1. Читаем HTTP-заголовки (фейковый WebSocket upgrade).
/// parsing would be a place for the relay to disagree with the endpoints. /// 2. Извлекаем HMAC-подпись из Authorization: Bearer.
async fn splice_tcp(mut client: TcpStream, upstream_addr: &str) -> Result<()> { /// 3. Проверяем подпись по синхронизированным ключам.
let mut upstream = tokio::time::timeout( /// 4. Если авторизован — открываем соединение к upstream и пайпим потоки.
UPSTREAM_CONNECT_TIMEOUT, async fn handle_tcp_client(
TcpStream::connect(upstream_addr), mut client: TcpStream,
peer_addr: SocketAddr,
upstream_addr: String,
shared_keys: SharedKeys,
) -> Result<()> {
// Читаем HTTP-заголовки (до \r\n\r\n)
let mut header_buf = vec![0u8; 4096];
let mut header_len = 0usize;
loop {
let n = client.read(&mut header_buf[header_len..]).await?;
if n == 0 {
anyhow::bail!("connection closed before handshake");
}
header_len += n;
if header_buf[..header_len].windows(4).any(|w| w == b"\r\n\r\n") {
break;
}
if header_len >= header_buf.len() {
anyhow::bail!("headers too large");
}
}
let headers_str = String::from_utf8_lossy(&header_buf[..header_len]);
// Быстрая проверка: должен быть GET /stream
if !headers_str.starts_with("GET /stream HTTP/1.1\r\n") {
// Возвращаем 404 как обычный сервер (anti-scan)
let _ = client.write_all(b"HTTP/1.1 404 Not Found\r\nContent-Length: 9\r\nConnection: close\r\n\r\nNot Found").await;
anyhow::bail!("invalid request from {}", peer_addr);
}
// Извлекаем HMAC-подпись
let mut sig_b64 = None;
for line in headers_str.lines() {
let lower = line.to_ascii_lowercase();
if lower.starts_with("authorization: bearer ") {
sig_b64 = Some(line[22..].trim().to_string());
} else if lower.starts_with("cookie: ostp_token=") {
sig_b64 = Some(line[19..].trim().to_string());
}
}
let sig_b64 = match sig_b64 {
Some(s) => s,
None => {
let _ = client.write_all(b"HTTP/1.1 404 Not Found\r\nContent-Length: 9\r\nConnection: close\r\n\r\nNot Found").await;
anyhow::bail!("missing authorization from {}", peer_addr);
}
};
let sig_bytes = base64::Engine::decode(
&base64::engine::general_purpose::STANDARD_NO_PAD,
&sig_b64,
) )
.await .map_err(|_| anyhow::anyhow!("invalid base64 from {}", peer_addr))?;
.map_err(|_| anyhow::anyhow!("upstream {upstream_addr} connect timed out"))?
.with_context(|| format!("connect to upstream {upstream_addr}"))?;
// Both sides carry latency-sensitive framed traffic; Nagle would add delay if sig_bytes.len() < 40 {
// for no benefit on an already-batched stream. let _ = client.write_all(b"HTTP/1.1 401 Unauthorized\r\nContent-Length: 12\r\nConnection: close\r\n\r\nUnauthorized").await;
let _ = client.set_nodelay(true); anyhow::bail!("signature too short from {}", peer_addr);
let _ = upstream.set_nodelay(true); }
tokio::io::copy_bidirectional(&mut client, &mut upstream).await?; let ts_bytes: [u8; 8] = sig_bytes[0..8].try_into().unwrap();
let provided_mac = &sig_bytes[8..];
// Проверяем по синхронизированным ключам
let authorized = {
let keys = shared_keys.read().unwrap_or_else(|e| e.into_inner());
verify_hmac(&ts_bytes, provided_mac, &keys)
};
if !authorized {
let _ = client.write_all(b"HTTP/1.1 404 Not Found\r\nContent-Length: 9\r\nConnection: close\r\n\r\nNot Found").await;
anyhow::bail!("unauthorized client {}", peer_addr);
}
tracing::info!("Relay TCP: authorized client {}, forwarding to {}", peer_addr, upstream_addr);
// Подключаемся к upstream
let mut upstream = TcpStream::connect(&upstream_addr).await
.map_err(|e| anyhow::anyhow!("failed to connect to upstream {}: {}", upstream_addr, e))?;
// Пересылаем upstream заголовки AS-IS (он сам проверит подпись)
upstream.write_all(&header_buf[..header_len]).await?;
// Пайпим оба потока: client <-> upstream
let (mut cr, mut cw) = client.into_split();
let (mut ur, mut uw) = upstream.into_split();
let c2u = tokio::spawn(async move {
let _ = tokio::io::copy(&mut cr, &mut uw).await;
});
let u2c = tokio::spawn(async move {
let _ = tokio::io::copy(&mut ur, &mut cw).await;
});
let _ = tokio::join!(c2u, u2c);
Ok(()) Ok(())
} }
#[cfg(test)]
mod tests {
use super::*;
/// The admission limiter is what replaced per-client authentication as the
/// defence against resource abuse, so it has to actually stop admitting.
#[test]
fn admission_limiter_stops_at_the_burst_ceiling() {
let mut limiter = AdmissionLimiter::new();
let mut admitted = 0usize;
// Ask for far more than one burst without letting time pass.
for _ in 0..(NEW_SESSION_RATE as usize * 3) {
if limiter.try_admit() {
admitted += 1;
}
}
assert!(
admitted <= NEW_SESSION_RATE as usize + 1,
"admitted {admitted} sessions in one instant, ceiling is {NEW_SESSION_RATE}"
);
assert!(admitted > 0, "limiter admitted nothing at all");
}
/// It must also refill, or the relay would accept a burst once and then
/// refuse every client forever.
#[test]
fn admission_limiter_refills_over_time() {
let mut limiter = AdmissionLimiter::new();
while limiter.try_admit() {}
assert!(!limiter.try_admit(), "bucket should be empty");
std::thread::sleep(Duration::from_millis(50));
assert!(
limiter.try_admit(),
"limiter never refilled; the relay would stop accepting new clients"
);
}
/// End-to-end through the real UDP path: a client datagram reaches the
/// upstream and the reply comes back to that same client. This is the whole
/// job of the relay, and it is what the previous implementation could not do
/// with a real client, because it demanded credentials no client sends.
#[tokio::test]
async fn udp_relay_forwards_both_directions() {
// Stand-in upstream that echoes with a marker.
let upstream = UdpSocket::bind("127.0.0.1:0").await.unwrap();
let upstream_addr = upstream.local_addr().unwrap();
tokio::spawn(async move {
let mut buf = [0u8; 1500];
while let Ok((n, from)) = upstream.recv_from(&mut buf).await {
let mut reply = b"echo:".to_vec();
reply.extend_from_slice(&buf[..n]);
let _ = upstream.send_to(&reply, from).await;
}
});
let relay_listen = {
let probe = UdpSocket::bind("127.0.0.1:0").await.unwrap();
let a = probe.local_addr().unwrap();
drop(probe);
a
};
tokio::spawn(run_udp_relay(RelayConfig {
listen_addrs: vec![relay_listen.to_string()],
upstream_tcp: upstream_addr.to_string(),
upstream_udp: upstream_addr.to_string(),
}));
tokio::time::sleep(Duration::from_millis(150)).await;
// A plain OSTP-looking datagram: no credentials, no preamble.
let client = UdpSocket::bind("127.0.0.1:0").await.unwrap();
client.send_to(b"opaque-payload", relay_listen).await.unwrap();
let mut buf = [0u8; 1500];
let (n, _) = tokio::time::timeout(Duration::from_secs(3), client.recv_from(&mut buf))
.await
.expect("relay did not deliver a reply within 3s")
.unwrap();
assert_eq!(
&buf[..n],
b"echo:opaque-payload",
"relay did not forward the payload verbatim in both directions"
);
}
/// Same for TCP: bytes must cross unmodified in both directions, with no
/// handshake demanded of the client.
#[tokio::test]
async fn tcp_relay_splices_both_directions() {
use tokio::io::{AsyncReadExt, AsyncWriteExt};
let upstream = TcpListener::bind("127.0.0.1:0").await.unwrap();
let upstream_addr = upstream.local_addr().unwrap();
tokio::spawn(async move {
if let Ok((mut sock, _)) = upstream.accept().await {
let mut buf = [0u8; 128];
if let Ok(n) = sock.read(&mut buf).await {
let mut reply = b"echo:".to_vec();
reply.extend_from_slice(&buf[..n]);
let _ = sock.write_all(&reply).await;
}
}
});
let relay_listen = {
let probe = TcpListener::bind("127.0.0.1:0").await.unwrap();
let a = probe.local_addr().unwrap();
drop(probe);
a
};
tokio::spawn(run_tcp_relay(RelayConfig {
listen_addrs: vec![relay_listen.to_string()],
upstream_tcp: upstream_addr.to_string(),
upstream_udp: upstream_addr.to_string(),
}));
tokio::time::sleep(Duration::from_millis(150)).await;
let mut client = TcpStream::connect(relay_listen).await.unwrap();
client.write_all(b"opaque-stream").await.unwrap();
let mut buf = [0u8; 128];
let n = tokio::time::timeout(Duration::from_secs(3), client.read(&mut buf))
.await
.expect("relay did not deliver a reply within 3s")
.unwrap();
assert_eq!(&buf[..n], b"echo:opaque-stream");
}
}

View File

@ -47,29 +47,12 @@ impl Router {
let mut proxy = None; let mut proxy = None;
if let Some(ref c) = cfg { if let Some(ref c) = cfg {
if c.enabled { if c.enabled && c.protocol == "socks5" {
if c.protocol == "socks5" { let proxy_addr = format!("{}:{}", c.address, c.port);
let proxy_addr = format!("{}:{}", c.address, c.port); if let Ok(p) = crate::outbound::connect_udp_via_socks5(&proxy_addr, server_udp.clone()).await {
match crate::outbound::connect_udp_via_socks5(&proxy_addr, server_udp.clone()).await { proxy = Some(Arc::new(p));
Ok(p) => proxy = Some(Arc::new(p)), } else if self.debug {
// Warn unconditionally, not only under `debug`. Every UDP tracing::warn!("Failed to establish SOCKS5 UDP Associate");
// flow the rules want proxied is now dropped instead of
// sent, so an operator who cannot see this has a session
// where TCP works and UDP silently does not.
Err(e) => tracing::warn!(
"SOCKS5 UDP ASSOCIATE to {proxy_addr} failed: {e}. UDP that the \
outbound rules route through the proxy will be DROPPED (it is not \
sent directly, which would expose this server's address)."
),
}
} else {
tracing::warn!(
"Upstream proxy protocol is '{}', which cannot carry UDP. UDP matching \
a Proxy rule will be DROPPED. Use a socks5 upstream for UDP, or add an \
explicit udp rule with action \"direct\" or \"block\" to make the \
intent explicit.",
c.protocol
);
} }
} }
} }
@ -104,28 +87,9 @@ impl UdpSessionRouter {
return Err(anyhow::anyhow!("blocked by outbound udp rule: {}", target)); return Err(anyhow::anyhow!("blocked by outbound udp rule: {}", target));
} }
if action == crate::outbound::OutboundAction::Proxy { if action == crate::outbound::OutboundAction::Proxy {
return match &self.proxy { if let Some(p) = &self.proxy {
Some(p) => p.send_to(data, target).await, return p.send_to(data, target).await;
// FAIL CLOSED. This used to fall through to the direct }
// socket, so whenever the UDP proxy was unavailable —
// the SOCKS5 UDP ASSOCIATE failed, or the upstream is an
// HTTP proxy, which cannot carry UDP at all — every UDP
// datagram silently egressed from the server's own
// address while TCP still went through the proxy. The
// session then had two different exit IPs, which is what
// Google flags and why YouTube (QUIC, i.e. UDP/443)
// geolocated to the server instead of the proxy exit.
//
// A rule that says "proxy" must never be satisfied by
// sending in the clear: a dropped datagram is visible and
// debuggable, a deanonymising leak is neither.
None => Err(anyhow::anyhow!(
"outbound rule requires the proxy for UDP to {target}, but no UDP \
proxy is available (SOCKS5 UDP ASSOCIATE failed, or the upstream \
is an HTTP proxy, which cannot carry UDP) - dropping rather than \
leaking the server's own address"
)),
};
} }
} }
} }

View File

@ -799,16 +799,18 @@ fn run_setup_wizard(config_path: &std::path::Path) -> Result<()> {
let listen = wizard_prompt("Listen address (host:port)", "0.0.0.0:50000"); let listen = wizard_prompt("Listen address (host:port)", "0.0.0.0:50000");
let upstream = wizard_prompt("Upstream server address (host:port)", ""); let upstream = wizard_prompt("Upstream server address (host:port)", "");
if upstream.is_empty() { anyhow::bail!("Upstream address cannot be empty."); } if upstream.is_empty() { anyhow::bail!("Upstream address cannot be empty."); }
let api_url = wizard_prompt("Upstream server API URL (e.g. http://1.2.3.4:9090)", "");
let api_token = wizard_prompt("Upstream API token (leave blank if none)", "");
wizard_step(2, TOTAL, "Saving configuration"); wizard_step(2, TOTAL, "Saving configuration");
// No credentials are collected: the relay forwards transparently and
// authenticates nothing, so it needs neither the target's API nor a
// copy of the access keys.
let relay_json = serde_json::json!({ let relay_json = serde_json::json!({
"mode": "relay", "mode": "relay",
"listen": listen, "listen": listen,
"upstream_tcp": upstream, "upstream_tcp": upstream,
"upstream_udp": upstream, "upstream_udp": upstream,
"upstream_api_url": api_url,
"upstream_api_token": api_token,
"sync_interval_secs": 30,
"debug": false "debug": false
}); });
@ -1135,9 +1137,7 @@ async fn run_app() -> Result<()> {
println!(" Listen: {:?}", r.listen.primary().cyan()); println!(" Listen: {:?}", r.listen.primary().cyan());
println!(" Upstream TCP: {}", r.upstream_tcp.cyan()); println!(" Upstream TCP: {}", r.upstream_tcp.cyan());
println!(" Upstream UDP: {}", r.upstream_udp.cyan()); println!(" Upstream UDP: {}", r.upstream_udp.cyan());
if !r.upstream_api_url.is_empty() { println!(" API sync: {}", r.upstream_api_url.yellow());
println!(" {}", "upstream_api_url is set but no longer used - safe to remove".yellow());
}
} }
} }
} }
@ -1213,9 +1213,9 @@ async fn run_app() -> Result<()> {
"listen": "0.0.0.0:50000", "listen": "0.0.0.0:50000",
"upstream_tcp": "TARGET_SERVER_IP:50000", "upstream_tcp": "TARGET_SERVER_IP:50000",
"upstream_udp": "TARGET_SERVER_IP:50000", "upstream_udp": "TARGET_SERVER_IP:50000",
// The relay forwards transparently and holds no keys: sessions are "upstream_api_url": "http://TARGET_SERVER_IP:9090",
// authenticated end-to-end by the target server, which drops anything that "upstream_api_token": "YOUR_API_TOKEN_HERE",
// fails. Nothing else needs configuring here. "sync_interval_secs": 30,
"debug": false "debug": false
}"#.to_string() }"#.to_string()
} else { } else {
@ -1414,18 +1414,14 @@ async fn run_app() -> Result<()> {
println!("{} Starting relay node on {:?}", "[ostp]".cyan().bold(), listen_addrs); println!("{} Starting relay node on {:?}", "[ostp]".cyan().bold(), listen_addrs);
println!("{} Upstream TCP: {}", "[ostp]".cyan().bold(), relay_cfg.upstream_tcp); println!("{} Upstream TCP: {}", "[ostp]".cyan().bold(), relay_cfg.upstream_tcp);
println!("{} Upstream UDP: {}", "[ostp]".cyan().bold(), relay_cfg.upstream_udp); println!("{} Upstream UDP: {}", "[ostp]".cyan().bold(), relay_cfg.upstream_udp);
if !relay_cfg.upstream_api_url.is_empty() { println!("{} Key sync API: {}", "[ostp]".cyan().bold(), relay_cfg.upstream_api_url);
println!(
"{} Note: upstream_api_url is no longer used and can be removed. The relay \
forwards transparently; sessions are authenticated end-to-end by the target \
server.",
"[ostp]".yellow().bold()
);
}
let relay_config = ostp_server::RelayConfig { let relay_config = ostp_server::RelayConfig {
listen_addrs, listen_addrs,
upstream_tcp: relay_cfg.upstream_tcp, upstream_tcp: relay_cfg.upstream_tcp,
upstream_udp: relay_cfg.upstream_udp, upstream_udp: relay_cfg.upstream_udp,
upstream_api_url: relay_cfg.upstream_api_url,
upstream_api_token: relay_cfg.upstream_api_token,
sync_interval_secs: relay_cfg.sync_interval_secs,
}; };
ostp_server::relay_node::run_relay_node(relay_config).await?; ostp_server::relay_node::run_relay_node(relay_config).await?;
} }