PhrescoFileServer.java

/*
 * ###
 * Phresco File Server
 * 
 * Copyright (C) 1999 - 2012 Photon Infotech Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ###
 */
package com.photon.phresco.fileserver;

import java.net.*;
import java.io.*;
import java.util.*;

public class PhrescoFileServer
{
	public static void main(String[] args) {
		// read arguments
		if (args.length != 2) {
			System.out.println("Usage: java FileServer <port> <wwwhome>");
			System.exit(-1);
		}
		int port = Integer.parseInt(args[0]);
		String wwwhome = args[1];

		// open server socket
		ServerSocket socket = null;
		try {
			socket = new ServerSocket(port);
		} catch (IOException e) {
			System.err.println("Could not start server: " + e);
			System.exit(-1);
		}
		System.out.println("FileServer accepting connections on port " + port);
		// request handler loop
		while (true) {
			Socket connection = null;
			try {
				// wait for request
				connection = socket.accept();
				BufferedReader in = new BufferedReader(new InputStreamReader(
						connection.getInputStream()));
				OutputStream out = new BufferedOutputStream(
						connection.getOutputStream());
				PrintStream pout = new PrintStream(out);

				// read first line of request (ignore the rest)
				String request = in.readLine();
				if (request == null)
					continue;
				log(connection, request);
				while (true) {
					String misc = in.readLine();
					if (misc == null || misc.length() == 0)
						break;
				}

				// parse the line
				if (!request.startsWith("GET")
						|| request.length() < 14
						|| !(request.endsWith("HTTP/1.0") || request
								.endsWith("HTTP/1.1"))) {
					// bad request
					errorReport(pout, connection, "400", "Bad Request",
							"Your browser sent a request that "
									+ "this server could not understand.");
				} else {
					String req = request.substring(4, request.length() - 9)
							.trim();
					if (req.indexOf("..") != -1 || req.indexOf("/.ht") != -1
							|| req.endsWith("~")) {
						// evil hacker trying to read non-wwwhome or secret file
						errorReport(pout, connection, "403", "Forbidden",
								"You don't have permission to access the requested URL.");
					} else {
						String path = wwwhome + "/" + req;
						File f = new File(path);
						if (f.isDirectory() && !path.endsWith("/")) {
							// redirect browser if referring to directory
							// without final '/'
							pout.print("HTTP/1.0 301 Moved Permanently\r\n"
									+ "Location: http://"
									+ connection.getLocalAddress()
											.getHostAddress() + ":"
									+ connection.getLocalPort() + "/" + req
									+ "/\r\n\r\n");
							log(connection, "301 Moved Permanently");
						} else {
							if (f.isDirectory()) {
								// if directory, implicitly add 'index.html'
								path = path + "index.html";
								f = new File(path);
							}
							try {
								// send file
								InputStream file = new FileInputStream(f);
								pout.print("HTTP/1.0 200 OK\r\n"
										+ "Content-Type: "
										+ guessContentType(path) + "\r\n"
										+ "Date: " + new Date() + "\r\n"
										+ "Server: FileServer 1.0\r\n\r\n");
								sendFile(file, out); // send raw file
								log(connection, "200 OK");
							} catch (FileNotFoundException e) {
								// file not found
								errorReport(pout, connection, "404",
										"Not Found",
										"The requested URL was not found on this server.");
							}
						}
					}
				}
				out.flush();
			} catch (IOException e) {
				System.err.println(e);
			}
			try {
				if (connection != null)
					connection.close();
			} catch (IOException e) {
				System.err.println(e);
			}
		}
	}

	private static void log(Socket connection, String msg) {
		//System.err.println(new Date() + " ["
		//		+ connection.getInetAddress().getHostAddress() + ":"
		//		+ connection.getPort() + "] " + msg);
	}

	private static void errorReport(PrintStream pout, Socket connection,
			String code, String title, String msg) {
		pout.print("HTTP/1.0 " + code + " " + title + "\r\n" + "\r\n"
				+ "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">\r\n"
				+ "<TITLE>" + code + " " + title + "</TITLE>\r\n"
				+ "</HEAD><BODY>\r\n" + "<H1>" + title + "</H1>\r\n" + msg
				+ "<P>\r\n" + "<HR><ADDRESS>FileServer 1.0 at "
				+ connection.getLocalAddress().getHostName() + " Port "
				+ connection.getLocalPort() + "</ADDRESS>\r\n"
				+ "</BODY></HTML>\r\n");
		log(connection, code + " " + title);
	}

	private static String guessContentType(String path) {
		if (path.endsWith(".html") || path.endsWith(".htm"))
			return "text/html";
		else if (path.endsWith(".txt") || path.endsWith(".java"))
			return "text/plain";
		else if (path.endsWith(".gif"))
			return "image/gif";
		else if (path.endsWith(".class"))
			return "application/octet-stream";
		else if (path.endsWith(".jpg") || path.endsWith(".jpeg"))
			return "image/jpeg";
		else
			return "text/plain";
	}

	private static void sendFile(InputStream file, OutputStream out) {
		try {
			byte[] buffer = new byte[1000];
			while (file.available() > 0)
				out.write(buffer, 0, file.read(buffer));
		} catch (IOException e) {
			System.err.println(e);
		}
	}
}