661 lines
28 KiB
Rust
661 lines
28 KiB
Rust
//! Client Handler
|
|
|
|
use std::net::SocketAddr;
|
|
use std::sync::Arc;
|
|
use std::time::Duration;
|
|
use tokio::net::TcpStream;
|
|
use tokio::io::{AsyncRead, AsyncWrite, AsyncReadExt, AsyncWriteExt};
|
|
use tokio::time::timeout;
|
|
use tracing::{debug, info, warn, error, trace};
|
|
|
|
use crate::config::ProxyConfig;
|
|
use crate::error::{ProxyError, Result, HandshakeResult};
|
|
use crate::protocol::constants::*;
|
|
use crate::protocol::tls;
|
|
use crate::stats::{Stats, ReplayChecker};
|
|
use crate::transport::{configure_client_socket, UpstreamManager};
|
|
use crate::transport::middle_proxy::{MePool, MeResponse, proto_flags_for_tag};
|
|
use crate::stream::{CryptoReader, CryptoWriter, FakeTlsReader, FakeTlsWriter, BufferPool};
|
|
use crate::crypto::{AesCtr, SecureRandom};
|
|
|
|
use crate::proxy::handshake::{
|
|
handle_tls_handshake, handle_mtproto_handshake,
|
|
HandshakeSuccess, generate_tg_nonce, encrypt_tg_nonce,
|
|
};
|
|
use crate::proxy::relay::relay_bidirectional;
|
|
use crate::proxy::masking::handle_bad_client;
|
|
|
|
pub struct ClientHandler;
|
|
|
|
pub struct RunningClientHandler {
|
|
stream: TcpStream,
|
|
peer: SocketAddr,
|
|
config: Arc<ProxyConfig>,
|
|
stats: Arc<Stats>,
|
|
replay_checker: Arc<ReplayChecker>,
|
|
upstream_manager: Arc<UpstreamManager>,
|
|
buffer_pool: Arc<BufferPool>,
|
|
rng: Arc<SecureRandom>,
|
|
me_pool: Option<Arc<MePool>>,
|
|
}
|
|
|
|
impl ClientHandler {
|
|
pub fn new(
|
|
stream: TcpStream,
|
|
peer: SocketAddr,
|
|
config: Arc<ProxyConfig>,
|
|
stats: Arc<Stats>,
|
|
upstream_manager: Arc<UpstreamManager>,
|
|
replay_checker: Arc<ReplayChecker>,
|
|
buffer_pool: Arc<BufferPool>,
|
|
rng: Arc<SecureRandom>,
|
|
me_pool: Option<Arc<MePool>>,
|
|
) -> RunningClientHandler {
|
|
RunningClientHandler {
|
|
stream, peer, config, stats, replay_checker,
|
|
upstream_manager, buffer_pool, rng, me_pool,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl RunningClientHandler {
|
|
pub async fn run(mut self) -> Result<()> {
|
|
self.stats.increment_connects_all();
|
|
|
|
let peer = self.peer;
|
|
debug!(peer = %peer, "New connection");
|
|
|
|
if let Err(e) = configure_client_socket(
|
|
&self.stream,
|
|
self.config.timeouts.client_keepalive,
|
|
self.config.timeouts.client_ack,
|
|
) {
|
|
debug!(peer = %peer, error = %e, "Failed to configure client socket");
|
|
}
|
|
|
|
let handshake_timeout = Duration::from_secs(self.config.timeouts.client_handshake);
|
|
let stats = self.stats.clone();
|
|
|
|
let result = timeout(handshake_timeout, self.do_handshake()).await;
|
|
|
|
match result {
|
|
Ok(Ok(())) => {
|
|
debug!(peer = %peer, "Connection handled successfully");
|
|
Ok(())
|
|
}
|
|
Ok(Err(e)) => {
|
|
debug!(peer = %peer, error = %e, "Handshake failed");
|
|
Err(e)
|
|
}
|
|
Err(_) => {
|
|
stats.increment_handshake_timeouts();
|
|
debug!(peer = %peer, "Handshake timeout");
|
|
Err(ProxyError::TgHandshakeTimeout)
|
|
}
|
|
}
|
|
}
|
|
|
|
async fn do_handshake(mut self) -> Result<()> {
|
|
let mut first_bytes = [0u8; 5];
|
|
self.stream.read_exact(&mut first_bytes).await?;
|
|
|
|
let is_tls = tls::is_tls_handshake(&first_bytes[..3]);
|
|
let peer = self.peer;
|
|
|
|
debug!(peer = %peer, is_tls = is_tls, "Handshake type detected");
|
|
|
|
if is_tls {
|
|
self.handle_tls_client(first_bytes).await
|
|
} else {
|
|
self.handle_direct_client(first_bytes).await
|
|
}
|
|
}
|
|
|
|
async fn handle_tls_client(mut self, first_bytes: [u8; 5]) -> Result<()> {
|
|
let peer = self.peer;
|
|
|
|
let tls_len = u16::from_be_bytes([first_bytes[3], first_bytes[4]]) as usize;
|
|
|
|
debug!(peer = %peer, tls_len = tls_len, "Reading TLS handshake");
|
|
|
|
if tls_len < 512 {
|
|
debug!(peer = %peer, tls_len = tls_len, "TLS handshake too short");
|
|
self.stats.increment_connects_bad();
|
|
let (reader, writer) = self.stream.into_split();
|
|
handle_bad_client(reader, writer, &first_bytes, &self.config).await;
|
|
return Ok(());
|
|
}
|
|
|
|
let mut handshake = vec![0u8; 5 + tls_len];
|
|
handshake[..5].copy_from_slice(&first_bytes);
|
|
self.stream.read_exact(&mut handshake[5..]).await?;
|
|
|
|
let config = self.config.clone();
|
|
let replay_checker = self.replay_checker.clone();
|
|
let stats = self.stats.clone();
|
|
let buffer_pool = self.buffer_pool.clone();
|
|
|
|
let (read_half, write_half) = self.stream.into_split();
|
|
|
|
let (mut tls_reader, tls_writer, _tls_user) = match handle_tls_handshake(
|
|
&handshake, read_half, write_half, peer,
|
|
&config, &replay_checker, &self.rng,
|
|
).await {
|
|
HandshakeResult::Success(result) => result,
|
|
HandshakeResult::BadClient { reader, writer } => {
|
|
stats.increment_connects_bad();
|
|
handle_bad_client(reader, writer, &handshake, &config).await;
|
|
return Ok(());
|
|
}
|
|
HandshakeResult::Error(e) => return Err(e),
|
|
};
|
|
|
|
debug!(peer = %peer, "Reading MTProto handshake through TLS");
|
|
let mtproto_data = tls_reader.read_exact(HANDSHAKE_LEN).await?;
|
|
let mtproto_handshake: [u8; HANDSHAKE_LEN] = mtproto_data[..].try_into()
|
|
.map_err(|_| ProxyError::InvalidHandshake("Short MTProto handshake".into()))?;
|
|
|
|
let (crypto_reader, crypto_writer, success) = match handle_mtproto_handshake(
|
|
&mtproto_handshake, tls_reader, tls_writer, peer,
|
|
&config, &replay_checker, true,
|
|
).await {
|
|
HandshakeResult::Success(result) => result,
|
|
HandshakeResult::BadClient { reader: _, writer: _ } => {
|
|
stats.increment_connects_bad();
|
|
debug!(peer = %peer, "Valid TLS but invalid MTProto handshake");
|
|
return Ok(());
|
|
}
|
|
HandshakeResult::Error(e) => return Err(e),
|
|
};
|
|
|
|
Self::handle_authenticated_static(
|
|
crypto_reader, crypto_writer, success,
|
|
self.upstream_manager, self.stats, self.config,
|
|
buffer_pool, self.rng, self.me_pool,
|
|
).await
|
|
}
|
|
|
|
async fn handle_direct_client(mut self, first_bytes: [u8; 5]) -> Result<()> {
|
|
let peer = self.peer;
|
|
|
|
if !self.config.general.modes.classic && !self.config.general.modes.secure {
|
|
debug!(peer = %peer, "Non-TLS modes disabled");
|
|
self.stats.increment_connects_bad();
|
|
let (reader, writer) = self.stream.into_split();
|
|
handle_bad_client(reader, writer, &first_bytes, &self.config).await;
|
|
return Ok(());
|
|
}
|
|
|
|
let mut handshake = [0u8; HANDSHAKE_LEN];
|
|
handshake[..5].copy_from_slice(&first_bytes);
|
|
self.stream.read_exact(&mut handshake[5..]).await?;
|
|
|
|
let config = self.config.clone();
|
|
let replay_checker = self.replay_checker.clone();
|
|
let stats = self.stats.clone();
|
|
let buffer_pool = self.buffer_pool.clone();
|
|
|
|
let (read_half, write_half) = self.stream.into_split();
|
|
|
|
let (crypto_reader, crypto_writer, success) = match handle_mtproto_handshake(
|
|
&handshake, read_half, write_half, peer,
|
|
&config, &replay_checker, false,
|
|
).await {
|
|
HandshakeResult::Success(result) => result,
|
|
HandshakeResult::BadClient { reader, writer } => {
|
|
stats.increment_connects_bad();
|
|
handle_bad_client(reader, writer, &handshake, &config).await;
|
|
return Ok(());
|
|
}
|
|
HandshakeResult::Error(e) => return Err(e),
|
|
};
|
|
|
|
Self::handle_authenticated_static(
|
|
crypto_reader, crypto_writer, success,
|
|
self.upstream_manager, self.stats, self.config,
|
|
buffer_pool, self.rng, self.me_pool,
|
|
).await
|
|
}
|
|
|
|
/// Main dispatch after successful handshake.
|
|
/// Two modes:
|
|
/// - Direct: TCP relay to TG DC (existing behavior)
|
|
/// - Middle Proxy: RPC multiplex through ME pool (new — supports CDN DCs)
|
|
async fn handle_authenticated_static<R, W>(
|
|
client_reader: CryptoReader<R>,
|
|
client_writer: CryptoWriter<W>,
|
|
success: HandshakeSuccess,
|
|
upstream_manager: Arc<UpstreamManager>,
|
|
stats: Arc<Stats>,
|
|
config: Arc<ProxyConfig>,
|
|
buffer_pool: Arc<BufferPool>,
|
|
rng: Arc<SecureRandom>,
|
|
me_pool: Option<Arc<MePool>>,
|
|
) -> Result<()>
|
|
where
|
|
R: AsyncRead + Unpin + Send + 'static,
|
|
W: AsyncWrite + Unpin + Send + 'static,
|
|
{
|
|
let user = &success.user;
|
|
|
|
if let Err(e) = Self::check_user_limits_static(user, &config, &stats) {
|
|
warn!(user = %user, error = %e, "User limit exceeded");
|
|
return Err(e);
|
|
}
|
|
|
|
// Decide: middle proxy or direct
|
|
if config.general.use_middle_proxy {
|
|
if let Some(ref pool) = me_pool {
|
|
return Self::handle_via_middle_proxy(
|
|
client_reader, client_writer, success,
|
|
pool.clone(), stats, config, buffer_pool,
|
|
).await;
|
|
}
|
|
warn!("use_middle_proxy=true but MePool not initialized, falling back to direct");
|
|
}
|
|
|
|
// Direct mode (original behavior)
|
|
Self::handle_via_direct(
|
|
client_reader, client_writer, success,
|
|
upstream_manager, stats, config, buffer_pool, rng,
|
|
).await
|
|
}
|
|
|
|
// =====================================================================
|
|
// Direct mode — TCP relay to Telegram DC
|
|
// =====================================================================
|
|
|
|
async fn handle_via_direct<R, W>(
|
|
client_reader: CryptoReader<R>,
|
|
client_writer: CryptoWriter<W>,
|
|
success: HandshakeSuccess,
|
|
upstream_manager: Arc<UpstreamManager>,
|
|
stats: Arc<Stats>,
|
|
config: Arc<ProxyConfig>,
|
|
buffer_pool: Arc<BufferPool>,
|
|
rng: Arc<SecureRandom>,
|
|
) -> Result<()>
|
|
where
|
|
R: AsyncRead + Unpin + Send + 'static,
|
|
W: AsyncWrite + Unpin + Send + 'static,
|
|
{
|
|
let user = &success.user;
|
|
let dc_addr = Self::get_dc_addr_static(success.dc_idx, &config)?;
|
|
|
|
info!(
|
|
user = %user,
|
|
peer = %success.peer,
|
|
dc = success.dc_idx,
|
|
dc_addr = %dc_addr,
|
|
proto = ?success.proto_tag,
|
|
mode = "direct",
|
|
"Connecting to Telegram DC"
|
|
);
|
|
|
|
let tg_stream = upstream_manager.connect(dc_addr, Some(success.dc_idx)).await?;
|
|
|
|
debug!(peer = %success.peer, dc_addr = %dc_addr, "Connected, performing TG handshake");
|
|
|
|
let (tg_reader, tg_writer) = Self::do_tg_handshake_static(
|
|
tg_stream, &success, &config, rng.as_ref(),
|
|
).await?;
|
|
|
|
debug!(peer = %success.peer, "TG handshake complete, starting relay");
|
|
|
|
stats.increment_user_connects(user);
|
|
stats.increment_user_curr_connects(user);
|
|
|
|
let relay_result = relay_bidirectional(
|
|
client_reader, client_writer,
|
|
tg_reader, tg_writer,
|
|
user, Arc::clone(&stats), buffer_pool,
|
|
).await;
|
|
|
|
stats.decrement_user_curr_connects(user);
|
|
|
|
match &relay_result {
|
|
Ok(()) => debug!(user = %user, "Direct relay completed"),
|
|
Err(e) => debug!(user = %user, error = %e, "Direct relay ended with error"),
|
|
}
|
|
|
|
relay_result
|
|
}
|
|
|
|
// =====================================================================
|
|
// Middle Proxy mode — RPC multiplex through ME pool
|
|
// =====================================================================
|
|
|
|
/// Middle Proxy RPC relay
|
|
///
|
|
/// Architecture (matches C MTProxy):
|
|
/// ```text
|
|
/// Client ←AES-CTR→ [telemt] ←RPC/AES-CBC→ ME ←internal→ DC (any, incl CDN 203)
|
|
/// ```
|
|
///
|
|
/// Key difference from direct mode:
|
|
/// - No per-client TCP to DC; all clients share ME pool connections
|
|
/// - ME internally routes to correct DC based on client's encrypted auth_key_id
|
|
/// - CDN DCs (203+) work because ME knows their internal addresses
|
|
/// - We pass raw client MTProto bytes in RPC_PROXY_REQ envelope
|
|
/// - ME returns responses in RPC_PROXY_ANS envelope
|
|
|
|
async fn handle_via_middle_proxy<R, W>(
|
|
mut client_reader: CryptoReader<R>,
|
|
mut client_writer: CryptoWriter<W>,
|
|
success: HandshakeSuccess,
|
|
me_pool: Arc<MePool>,
|
|
stats: Arc<Stats>,
|
|
config: Arc<ProxyConfig>,
|
|
_buffer_pool: Arc<BufferPool>,
|
|
) -> Result<()>
|
|
where
|
|
R: AsyncRead + Unpin + Send + 'static,
|
|
W: AsyncWrite + Unpin + Send + 'static,
|
|
{
|
|
let user = success.user.clone();
|
|
let peer = success.peer;
|
|
|
|
info!(
|
|
user = %user,
|
|
peer = %peer,
|
|
dc = success.dc_idx,
|
|
proto = ?success.proto_tag,
|
|
mode = "middle_proxy",
|
|
"Routing via Middle-End"
|
|
);
|
|
|
|
let (conn_id, mut me_rx) = me_pool.registry().register().await;
|
|
|
|
let our_addr: SocketAddr = format!("0.0.0.0:{}", config.server.port)
|
|
.parse().unwrap_or_else(|_| "0.0.0.0:443".parse().unwrap());
|
|
|
|
stats.increment_user_connects(&user);
|
|
stats.increment_user_curr_connects(&user);
|
|
|
|
let proto_flags = proto_flags_for_tag(success.proto_tag);
|
|
debug!(user = %user, conn_id, proto_flags = format_args!("0x{:08x}", proto_flags), "ME relay started");
|
|
|
|
// We need to handle framing here.
|
|
// Client sends: [Len:4][Payload...] (Intermediate/Secure)
|
|
// We must strip Len and send Payload to ME.
|
|
// ME sends: [Payload...]
|
|
// We must add [Len:4] and send to Client.
|
|
|
|
// For Secure mode, Len has padding bit (MSB).
|
|
let is_secure = success.proto_tag == crate::protocol::constants::ProtoTag::Secure;
|
|
|
|
let mut client_closed = false;
|
|
let mut server_closed = false;
|
|
|
|
// Split client_reader/writer to use in select!
|
|
// CryptoReader/Writer don't support splitting easily without Arc/Mutex or unsafe,
|
|
// but here we are in a loop.
|
|
// We can't easily split them because they wrap the underlying stream.
|
|
// However, we can use a loop with select! on read and rx.
|
|
|
|
let mut len_buf = [0u8; 4];
|
|
let mut reading_len = true;
|
|
let mut current_payload_len = 0;
|
|
let mut payload_buf = Vec::new();
|
|
|
|
let result: Result<()> = loop {
|
|
tokio::select! {
|
|
// C->S: Read length, then payload
|
|
res = async {
|
|
if reading_len {
|
|
client_reader.read_exact(&mut len_buf).await.map(|_| true)
|
|
} else {
|
|
// Read payload
|
|
// We need to read exactly current_payload_len
|
|
if payload_buf.len() < current_payload_len {
|
|
let needed = current_payload_len - payload_buf.len();
|
|
let mut chunk = vec![0u8; needed];
|
|
let n = client_reader.read(&mut chunk).await?;
|
|
if n == 0 { return Ok(false); } // EOF
|
|
payload_buf.extend_from_slice(&chunk[..n]);
|
|
Ok(true)
|
|
} else {
|
|
Ok(true) // Should not happen
|
|
}
|
|
}
|
|
}, if !client_closed => {
|
|
match res {
|
|
Ok(true) => {
|
|
if reading_len {
|
|
// Got length
|
|
let raw_len = u32::from_le_bytes(len_buf);
|
|
// In secure mode, MSB is padding flag. In intermediate, it's just len.
|
|
// But wait, standard intermediate doesn't use MSB for padding.
|
|
// Secure mode DOES.
|
|
// Let's trust the protocol tag.
|
|
let len = if is_secure {
|
|
raw_len & 0x7FFFFFFF
|
|
} else {
|
|
raw_len
|
|
};
|
|
|
|
current_payload_len = len as usize;
|
|
// Sanity check
|
|
if current_payload_len > 16 * 1024 * 1024 {
|
|
debug!(conn_id, len=current_payload_len, "Client sent huge frame");
|
|
break Err(ProxyError::Proxy("Frame too large".into()));
|
|
}
|
|
payload_buf.clear();
|
|
payload_buf.reserve(current_payload_len);
|
|
reading_len = false;
|
|
} else {
|
|
// Got some payload data
|
|
if payload_buf.len() == current_payload_len {
|
|
// Full frame received
|
|
trace!(conn_id, bytes = current_payload_len, "C->ME (Frame complete)");
|
|
stats.add_user_octets_from(&user, current_payload_len as u64);
|
|
|
|
// Send to ME
|
|
// Note: In secure mode, we send the PADDING bytes too?
|
|
// Erlang mtp_intermediate: strips 4 bytes len.
|
|
// Erlang mtp_secure: strips 4 bytes len.
|
|
// The payload includes the padding if it was added?
|
|
// Actually, secure layer (mtp_secure.erl) handles padding removal?
|
|
// No, mtp_secure just sets padding=>true for intermediate codec.
|
|
// The intermediate codec (mtp_intermediate.erl) just extracts the packet.
|
|
// The packet passed to RPC is the payload.
|
|
// If secure mode adds random padding at the end, it is part of the payload
|
|
// that ME receives?
|
|
// Let's look at C code.
|
|
// ext-server.c: reads packet_len.
|
|
// if (packet_len & 0x80000000) -> has padding.
|
|
// It reads the full packet.
|
|
// Then it passes it to forward_tcp_query.
|
|
// So YES, we send the full payload including padding to ME.
|
|
|
|
if let Err(e) = me_pool.send_proxy_req(
|
|
conn_id, peer, our_addr, &payload_buf, proto_flags
|
|
).await {
|
|
break Err(e);
|
|
}
|
|
|
|
// Reset for next frame
|
|
reading_len = true;
|
|
}
|
|
}
|
|
}
|
|
Ok(false) => {
|
|
// EOF
|
|
debug!(conn_id, "Client EOF");
|
|
client_closed = true;
|
|
let _ = me_pool.send_close(conn_id).await;
|
|
if server_closed { break Ok(()); }
|
|
}
|
|
Err(e) => {
|
|
debug!(conn_id, error = %e, "Client read error");
|
|
break Err(ProxyError::Io(e));
|
|
}
|
|
}
|
|
}
|
|
|
|
// S->C: ME sends data, we wrap and send to client
|
|
me_msg = me_rx.recv(), if !server_closed => {
|
|
match me_msg {
|
|
Some(MeResponse::Data(data)) => {
|
|
trace!(conn_id, bytes = data.len(), "ME->C");
|
|
stats.add_user_octets_to(&user, data.len() as u64);
|
|
|
|
// Wrap in intermediate frame
|
|
let len = data.len() as u32;
|
|
// For secure mode, we might need to add padding?
|
|
// C code: forward_mtproto_packet -> just sends data.
|
|
// But wait, C code adds framing in net-tcp-rpc-ext-server.c?
|
|
// No, forward_tcp_query sends RPC_PROXY_REQ.
|
|
// ME sends RPC_PROXY_ANS.
|
|
// The data in ANS is the MTProto packet.
|
|
// We need to send it to client.
|
|
// If client is Intermediate/Secure, we MUST add the 4-byte length prefix.
|
|
// Secure mode: usually we don't ADD padding on response, we just send valid packets.
|
|
// But we MUST send the length.
|
|
|
|
if let Err(e) = client_writer.write_all(&len.to_le_bytes()).await {
|
|
break Err(ProxyError::Io(e));
|
|
}
|
|
if let Err(e) = client_writer.write_all(&data).await {
|
|
break Err(ProxyError::Io(e));
|
|
}
|
|
if let Err(e) = client_writer.flush().await {
|
|
break Err(ProxyError::Io(e));
|
|
}
|
|
}
|
|
Some(MeResponse::Ack(_)) => {
|
|
trace!(conn_id, "ME ACK");
|
|
}
|
|
Some(MeResponse::Close) => {
|
|
debug!(conn_id, "ME sent CLOSE");
|
|
server_closed = true;
|
|
if client_closed { break Ok(()); }
|
|
// We should probably close client connection too
|
|
break Ok(());
|
|
}
|
|
None => {
|
|
debug!(conn_id, "ME channel closed");
|
|
server_closed = true;
|
|
if client_closed { break Ok(()); }
|
|
break Err(ProxyError::Proxy("ME connection lost".into()));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
// Cleanup
|
|
debug!(user = %user, conn_id, "ME relay cleanup");
|
|
me_pool.registry().unregister(conn_id).await;
|
|
stats.decrement_user_curr_connects(&user);
|
|
result
|
|
}
|
|
|
|
|
|
fn check_user_limits_static(user: &str, config: &ProxyConfig, stats: &Stats) -> Result<()> {
|
|
if let Some(expiration) = config.access.user_expirations.get(user) {
|
|
if chrono::Utc::now() > *expiration {
|
|
return Err(ProxyError::UserExpired { user: user.to_string() });
|
|
}
|
|
}
|
|
|
|
if let Some(limit) = config.access.user_max_tcp_conns.get(user) {
|
|
if stats.get_user_curr_connects(user) >= *limit as u64 {
|
|
return Err(ProxyError::ConnectionLimitExceeded { user: user.to_string() });
|
|
}
|
|
}
|
|
|
|
if let Some(quota) = config.access.user_data_quota.get(user) {
|
|
if stats.get_user_total_octets(user) >= *quota {
|
|
return Err(ProxyError::DataQuotaExceeded { user: user.to_string() });
|
|
}
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
|
|
/// Resolve DC index to target address (used only in direct mode)
|
|
fn get_dc_addr_static(dc_idx: i16, config: &ProxyConfig) -> Result<SocketAddr> {
|
|
let datacenters = if config.general.prefer_ipv6 {
|
|
&*TG_DATACENTERS_V6
|
|
} else {
|
|
&*TG_DATACENTERS_V4
|
|
};
|
|
|
|
let num_dcs = datacenters.len();
|
|
|
|
let dc_key = dc_idx.to_string();
|
|
if let Some(addr_str) = config.dc_overrides.get(&dc_key) {
|
|
match addr_str.parse::<SocketAddr>() {
|
|
Ok(addr) => {
|
|
debug!(dc_idx = dc_idx, addr = %addr, "Using DC override from config");
|
|
return Ok(addr);
|
|
}
|
|
Err(_) => {
|
|
warn!(dc_idx = dc_idx, addr_str = %addr_str,
|
|
"Invalid DC override address in config, ignoring");
|
|
}
|
|
}
|
|
}
|
|
|
|
let abs_dc = dc_idx.unsigned_abs() as usize;
|
|
if abs_dc >= 1 && abs_dc <= num_dcs {
|
|
return Ok(SocketAddr::new(datacenters[abs_dc - 1], TG_DATACENTER_PORT));
|
|
}
|
|
|
|
let default_dc = config.default_dc.unwrap_or(2) as usize;
|
|
let fallback_idx = if default_dc >= 1 && default_dc <= num_dcs {
|
|
default_dc - 1
|
|
} else {
|
|
1
|
|
};
|
|
|
|
info!(
|
|
original_dc = dc_idx,
|
|
fallback_dc = (fallback_idx + 1) as u16,
|
|
fallback_addr = %datacenters[fallback_idx],
|
|
"Special DC ---> default_cluster"
|
|
);
|
|
|
|
Ok(SocketAddr::new(datacenters[fallback_idx], TG_DATACENTER_PORT))
|
|
}
|
|
|
|
/// Perform obfuscated handshake with Telegram DC (direct mode only)
|
|
async fn do_tg_handshake_static(
|
|
mut stream: TcpStream,
|
|
success: &HandshakeSuccess,
|
|
config: &ProxyConfig,
|
|
rng: &SecureRandom,
|
|
) -> Result<(CryptoReader<tokio::net::tcp::OwnedReadHalf>, CryptoWriter<tokio::net::tcp::OwnedWriteHalf>)> {
|
|
let (nonce, tg_enc_key, tg_enc_iv, tg_dec_key, tg_dec_iv) = generate_tg_nonce(
|
|
success.proto_tag,
|
|
success.dc_idx,
|
|
&success.dec_key,
|
|
success.dec_iv,
|
|
rng,
|
|
config.general.fast_mode,
|
|
);
|
|
|
|
let encrypted_nonce = encrypt_tg_nonce(&nonce);
|
|
|
|
debug!(
|
|
peer = %success.peer,
|
|
nonce_head = %hex::encode(&nonce[..16]),
|
|
"Sending nonce to Telegram"
|
|
);
|
|
|
|
stream.write_all(&encrypted_nonce).await?;
|
|
stream.flush().await?;
|
|
|
|
let (read_half, write_half) = stream.into_split();
|
|
|
|
let decryptor = AesCtr::new(&tg_dec_key, tg_dec_iv);
|
|
let encryptor = AesCtr::new(&tg_enc_key, tg_enc_iv);
|
|
|
|
Ok((
|
|
CryptoReader::new(read_half, decryptor),
|
|
CryptoWriter::new(write_half, encryptor),
|
|
))
|
|
}
|
|
}
|
|
|