XX-net/XX-Net · warning

socks5 %r connect to %s:%d conn_id:%d closed:%r

Error message

socks5 %r connect to %s:%d conn_id:%d closed:%r

What it means

After a successful SOCKS5 CONNECT and create_conn, sending the success reply to the client raised (client vanished/reset). The tunnel conn is stopped via do_stop and the warning logged with the exception.

Source

Thrown at code/default/x_tunnel/local/proxy_handler.py:283

            return

        port = struct.unpack('>H', self.rfile.read(2))[0]

        conn_id = proxy_session.create_conn(sock, addr, port)
        if not conn_id:
            xlog.warn("socks5 create conn to %s:%d fail", addr, port)
            reply = b"\x05\x01\x00" + addrtype_pack + addr_pack + struct.pack(">H", port)
            sock.send(reply)
            return

        xlog.info("socks5 %r connect to %s:%d conn:%d", self.client_address, addr, port, conn_id)
        reply = b"\x05\x00\x00" + addrtype_pack + addr_pack + struct.pack(">H", port)
        try:
            sock.send(reply)
        except Exception as e:
            if conn_id in g.session.conn_list:
                g.session.conn_list[conn_id].do_stop("close_on_Socks5_reply")
            xlog.warn("socks5 %r connect to %s:%d conn_id:%d closed:%r", self.client_address, addr, port, conn_id, e)
            return

        if len(self.read_buffer) - self.buffer_start:
            g.session.conn_list[conn_id].transfer_received_data(self.read_buffer[self.buffer_start:])

        g.session.conn_list[conn_id].start(block=True)

    def https_handler(self):
        line = self.read_crlf_line()
        line = line.decode('iso-8859-1')
        words = line.split()
        if len(words) == 3:
            command, path, version = words
        elif len(words) == 2:
            command, path = words
            version = b"HTTP/1.1"
        else:
            xlog.warn("https req line fail:%s", line)

View on GitHub (pinned to cfa5bc17b6)

Solutions

1. Usually benign — the tunnel is cleaned up automatically
2. Increase client connect timeout if frequent
3. Check client-side network stability

try:
    sock.send(reply)
except Exception as e:
    g.session.conn_list[conn_id].do_stop('client_gone')

When it happens

Trigger: Client disconnects or RSTs between CONNECT request and reply; e.g. timeout or cancel in the client app.

Common situations: Apps with short connect timeouts, page navigations cancelling requests, mobile network switches.

Related errors

• do_unwrap_socks connect to x-tunnel for %s:%d proxy fail.
• request not supported command mode:%d
• request address type unknown:%d
• socks5 create conn to %s:%d fail
• https %r connect to %s:%d conn:%d closed.

AI-assisted analysis of XX-net/XX-Net@cfa5bc17b6 (2026-08-27). Data as JSON: /api/errors/3f871ac37e3752d5. Report an issue: GitHub.