| /* |
| * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| import java.net.*; |
| import java.io.*; |
| import java.util.*; |
| import java.security.*; |
| |
| /** |
| * A minimal proxy server that supports CONNECT tunneling. It does not do |
| * any header transformations. In future this could be added. |
| * Two threads are created per client connection. So, it's not |
| * intended for large numbers of parallel connections. |
| */ |
| public class ProxyServer extends Thread implements Closeable { |
| |
| ServerSocket listener; |
| int port; |
| volatile boolean debug; |
| |
| /** |
| * Create proxy on port (zero means don't care). Call getPort() |
| * to get the assigned port. |
| */ |
| public ProxyServer(Integer port) throws IOException { |
| this(port, false); |
| } |
| |
| public ProxyServer(Integer port, Boolean debug) throws IOException { |
| this.debug = debug; |
| listener = new ServerSocket(port); |
| this.port = listener.getLocalPort(); |
| setName("ProxyListener"); |
| setDaemon(true); |
| connections = new LinkedList<>(); |
| start(); |
| } |
| |
| public ProxyServer(String s) { } |
| |
| /** |
| * Returns the port number this proxy is listening on |
| */ |
| public int getPort() { |
| return port; |
| } |
| |
| /** |
| * Shuts down the proxy, probably aborting any connections |
| * currently open |
| */ |
| public void close() throws IOException { |
| if (debug) System.out.println("Proxy: closing"); |
| done = true; |
| listener.close(); |
| for (Connection c : connections) { |
| if (c.running()) { |
| c.close(); |
| } |
| } |
| } |
| |
| List<Connection> connections; |
| |
| volatile boolean done; |
| |
| public void run() { |
| if (System.getSecurityManager() == null) { |
| execute(); |
| } else { |
| // so calling domain does not need to have socket permission |
| AccessController.doPrivileged(new PrivilegedAction<Void>() { |
| public Void run() { |
| execute(); |
| return null; |
| } |
| }); |
| } |
| } |
| |
| public void execute() { |
| try { |
| while(!done) { |
| Socket s = listener.accept(); |
| if (debug) |
| System.out.println("Client: " + s); |
| Connection c = new Connection(s); |
| connections.add(c); |
| } |
| } catch(Throwable e) { |
| if (debug && !done) { |
| System.out.println("Fatal error: Listener: " + e); |
| e.printStackTrace(); |
| } |
| } |
| } |
| |
| /** |
| * Transparently forward everything, once we know what the destination is |
| */ |
| class Connection { |
| |
| Socket clientSocket, serverSocket; |
| Thread out, in; |
| volatile InputStream clientIn, serverIn; |
| volatile OutputStream clientOut, serverOut; |
| |
| boolean forwarding = false; |
| |
| final static int CR = 13; |
| final static int LF = 10; |
| |
| Connection(Socket s) throws IOException { |
| this.clientSocket= s; |
| this.clientIn = new BufferedInputStream(s.getInputStream()); |
| this.clientOut = s.getOutputStream(); |
| init(); |
| } |
| |
| byte[] readHeaders(InputStream is) throws IOException { |
| byte[] outbuffer = new byte[8000]; |
| int crlfcount = 0; |
| int bytecount = 0; |
| int c; |
| while ((c=is.read()) != -1 && bytecount < outbuffer.length) { |
| outbuffer[bytecount++] = (byte)c; |
| if (debug) System.out.write(c); |
| // were looking for CRLFCRLF sequence |
| if (c == CR || c == LF) { |
| switch(crlfcount) { |
| case 0: |
| if (c == CR) crlfcount ++; |
| break; |
| case 1: |
| if (c == LF) crlfcount ++; |
| break; |
| case 2: |
| if (c == CR) crlfcount ++; |
| break; |
| case 3: |
| if (c == LF) crlfcount ++; |
| break; |
| } |
| } else { |
| crlfcount = 0; |
| } |
| if (crlfcount == 4) { |
| break; |
| } |
| } |
| byte[] ret = new byte[bytecount]; |
| System.arraycopy(outbuffer, 0, ret, 0, bytecount); |
| return ret; |
| } |
| |
| boolean running() { |
| return out.isAlive() || in.isAlive(); |
| } |
| |
| public void close() throws IOException { |
| if (debug) System.out.println("Closing connection (proxy)"); |
| if (serverSocket != null) serverSocket.close(); |
| if (clientSocket != null) clientSocket.close(); |
| } |
| |
| int findCRLF(byte[] b) { |
| for (int i=0; i<b.length-1; i++) { |
| if (b[i] == CR && b[i+1] == LF) { |
| return i; |
| } |
| } |
| return -1; |
| } |
| |
| public void init() { |
| try { |
| byte[] buf = readHeaders(clientIn); |
| int p = findCRLF(buf); |
| if (p == -1) { |
| close(); |
| return; |
| } |
| String cmd = new String(buf, 0, p, "US-ASCII"); |
| String[] params = cmd.split(" "); |
| if (params[0].equals("CONNECT")) { |
| doTunnel(params[1]); |
| } else { |
| doProxy(params[1], buf, p, cmd); |
| } |
| } catch (IOException e) { |
| if (debug) { |
| System.out.println (e); |
| } |
| try {close(); } catch (IOException e1) {} |
| } |
| } |
| |
| void doProxy(String dest, byte[] buf, int p, String cmdLine) |
| throws IOException |
| { |
| try { |
| URI uri = new URI(dest); |
| if (!uri.isAbsolute()) { |
| throw new IOException("request URI not absolute"); |
| } |
| dest = uri.getAuthority(); |
| // now extract the path from the URI and recreate the cmd line |
| int sp = cmdLine.indexOf(' '); |
| String method = cmdLine.substring(0, sp); |
| cmdLine = method + " " + uri.getPath() + " HTTP/1.1"; |
| int x = cmdLine.length() - 1; |
| int i = p; |
| while (x >=0) { |
| buf[i--] = (byte)cmdLine.charAt(x--); |
| } |
| i++; |
| |
| commonInit(dest, 80); |
| serverOut.write(buf, i, buf.length-i); |
| proxyCommon(); |
| |
| } catch (URISyntaxException e) { |
| throw new IOException(e); |
| } |
| } |
| |
| void commonInit(String dest, int defaultPort) throws IOException { |
| int port; |
| String[] hostport = dest.split(":"); |
| if (hostport.length == 1) { |
| port = defaultPort; |
| } else { |
| port = Integer.parseInt(hostport[1]); |
| } |
| if (debug) System.out.printf("Server: (%s/%d)\n", hostport[0], port); |
| serverSocket = new Socket(hostport[0], port); |
| serverOut = serverSocket.getOutputStream(); |
| |
| serverIn = new BufferedInputStream(serverSocket.getInputStream()); |
| } |
| |
| void proxyCommon() throws IOException { |
| out = new Thread(() -> { |
| try { |
| byte[] bb = new byte[8000]; |
| int n; |
| while ((n = clientIn.read(bb)) != -1) { |
| serverOut.write(bb, 0, n); |
| } |
| serverSocket.close(); |
| clientSocket.close(); |
| } catch (IOException e) { |
| if (debug) { |
| System.out.println (e); |
| } |
| } |
| }); |
| in = new Thread(() -> { |
| try { |
| byte[] bb = new byte[8000]; |
| int n; |
| while ((n = serverIn.read(bb)) != -1) { |
| clientOut.write(bb, 0, n); |
| } |
| serverSocket.close(); |
| clientSocket.close(); |
| } catch (IOException e) { |
| if (debug) { |
| System.out.println(e); |
| e.printStackTrace(); |
| } |
| } |
| }); |
| out.setName("Proxy-outbound"); |
| out.setDaemon(true); |
| in.setDaemon(true); |
| in.setName("Proxy-inbound"); |
| out.start(); |
| in.start(); |
| } |
| |
| void doTunnel(String dest) throws IOException { |
| commonInit(dest, 443); |
| clientOut.write("HTTP/1.1 200 OK\r\n\r\n".getBytes()); |
| proxyCommon(); |
| } |
| } |
| |
| public static void main(String[] args) throws Exception { |
| int port = Integer.parseInt(args[0]); |
| boolean debug = args.length > 1 && args[1].equals("-debug"); |
| System.out.println("Debugging : " + debug); |
| ProxyServer ps = new ProxyServer(port, debug); |
| System.out.println("Proxy server listening on port " + ps.getPort()); |
| while (true) { |
| Thread.sleep(5000); |
| } |
| } |
| } |