feat(lite): merge TUN mode with IPv6 routing

2026-09-19 03:41:41 +08:00
parent 3e29012d9c
commit 50364dc17a
23 changed files with 2996 additions and 237 deletions
@@ -0,0 +1,121 @@
+#!/usr/bin/env python3
+"""RRPP 裸 UoT v2 relay。
+
+nginx 的 proxy_connect 模块负责 TLS、Basic Auth 和 CONNECT，relay 只监听
+127.0.0.1:15201，收到的首字节就是 UoT v2 request，不再解析 HTTP。
+"""
+
+from __future__ import annotations
+
+import ipaddress
+import logging
+import socket
+import struct
+import threading
+
+MAGIC = "sp.v2.udp-over-tcp.arpa"
+LISTEN_HOST = "127.0.0.1"
+LISTEN_PORT = 15201
+MAX_PACKET = 65535
+IDLE_TIMEOUT = 9 * 60
+
+
+def read_exact(conn: socket.socket, size: int) -> bytes:
+    data = bytearray()
+    while len(data) < size:
+        chunk = conn.recv(size - len(data))
+        if not chunk:
+            raise ConnectionError("客户端连接已关闭")
+        data.extend(chunk)
+    return bytes(data)
+
+
+def read_address(conn: socket.socket):
+    atyp = read_exact(conn, 1)[0]
+    if atyp == 0:
+        host = str(ipaddress.IPv4Address(read_exact(conn, 4)))
+    elif atyp == 1:
+        host = str(ipaddress.IPv6Address(read_exact(conn, 16)))
+    elif atyp == 2:
+        size = read_exact(conn, 1)[0]
+        host = read_exact(conn, size).decode("idna")
+    else:
+        raise ValueError(f"未知 UoT 地址类型: {atyp}")
+    return host, struct.unpack("!H", read_exact(conn, 2))[0]
+
+
+def encode_address(host: str, port: int) -> bytes:
+    try:
+        addr = ipaddress.ip_address(host)
+    except ValueError:
+        raw = host.encode("idna")
+        return b"\x02" + bytes([len(raw)]) + raw + struct.pack("!H", port)
+    return (b"\x00" if addr.version == 4 else b"\x01") + addr.packed + struct.pack("!H", port)
+
+
+def resolve_destination(host: str, port: int):
+    return socket.getaddrinfo(host, port, socket.AF_UNSPEC, socket.SOCK_DGRAM)[0][4]
+
+
+def handle(conn: socket.socket, peer):
+    udp = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    udp.settimeout(0.2)
+    # 与 nginx 的 10 分钟读写超时错开，空闲连接由 relay 先回收。
+    conn.settimeout(IDLE_TIMEOUT)
+    send_lock = threading.Lock()
+    try:
+        is_connect = read_exact(conn, 1)[0]
+        first_target = read_address(conn)
+        logging.info("UoT client %s target=%s:%s connect=%s", peer, *first_target, is_connect)
+
+        def udp_reader():
+            while True:
+                try:
+                    data, source = udp.recvfrom(MAX_PACKET)
+                except socket.timeout:
+                    continue
+                except OSError:
+                    return
+                try:
+                    with send_lock:
+                        if is_connect:
+                            conn.sendall(struct.pack("!H", len(data)) + data)
+                        else:
+                            conn.sendall(encode_address(source[0], source[1]) +
+                                          struct.pack("!H", len(data)) + data)
+                except OSError:
+                    return
+
+        threading.Thread(target=udp_reader, daemon=True).start()
+        if is_connect:
+            while True:
+                length = struct.unpack("!H", read_exact(conn, 2))[0]
+                payload = read_exact(conn, length)
+                udp.sendto(payload, resolve_destination(*first_target))
+        else:
+            while True:
+                destination = read_address(conn)
+                length = struct.unpack("!H", read_exact(conn, 2))[0]
+                payload = read_exact(conn, length)
+                udp.sendto(payload, resolve_destination(*destination))
+    except (ConnectionError, OSError, ValueError) as exc:
+        logging.info("UoT client %s closed: %s", peer, exc)
+    finally:
+        udp.close()
+        conn.close()
+
+
+def main():
+    logging.basicConfig(level=logging.INFO, format="%(asctime)s %(levelname)s %(message)s")
+    listener = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+    listener.bind((LISTEN_HOST, LISTEN_PORT))
+    listener.listen(128)
+    logging.info("RRPP UoT relay listening on %s:%d", LISTEN_HOST, LISTEN_PORT)
+    while True:
+        conn, peer = listener.accept()
+        threading.Thread(target=handle, args=(conn, peer), daemon=True).start()
+
+
+if __name__ == "__main__":
+    main()