package de.tudarmstadt.informatik.hostage.protocol;
import java.security.SecureRandom;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import java.util.Locale;
import java.util.TimeZone;
import de.tudarmstadt.informatik.hostage.commons.HelperUtils;
import de.tudarmstadt.informatik.hostage.wrapper.Packet;
/**
* HTTP protocol. Implementation of RFC document 1945. It can handle the
* following requests: GET, HEAD, TRACE, POST, DELETE. For all other requests
* '400 Bad Request' will be replied.
*
* @author Wulf Pfeiffer
*/
public class HTTP implements Protocol {
/**
* Get the current time in html header format.
*
* @return the formatted server time.
*/
private static String getServerTime() {
Calendar calendar = Calendar.getInstance();
SimpleDateFormat dateFormat = new SimpleDateFormat(
"EEE, dd MMM yyyy HH:mm:ss z", Locale.US);
dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
return dateFormat.format(calendar.getTime());
}
/** Whole request that was sent by the client */
private String request = "";
// version stuff
private static String[][][] possibleHttpVersions = {
{
{ "Apache/2.0." },
{ "28", "32", "35", "36", "39", "40", "42", "43", "44",
"45", "46", "47", "48", "49", "50", "51", "52",
"53", "54", "55", "58", "59", "61", "63", "64",
"65" } },
{
{ "Apache/2.2." },
{ "0", "2", "3", "4", "6", "8", "9", "10", "11", "12",
"13", "14", "15", "16", "17", "18", "19", "20",
"21", "22", "23", "24", "25" } },
{ { "Apache/2.3." },
{ "4", "5", "6", "8", "10", "11", "12", "14", "15", "16" } },
{ { "Apache/2.4." }, { "1", "2", "3", "4", "6" } } };
private static String serverVersion = initServerVersion();
private static String initServerVersion() {
SecureRandom rndm = new SecureRandom();
int majorVersion = rndm.nextInt(possibleHttpVersions.length);
return possibleHttpVersions[majorVersion][0][0]
+ possibleHttpVersions[majorVersion][1][rndm
.nextInt(possibleHttpVersions[majorVersion][1].length)];
}
private String httpVersion = "HTTP/1.1";
private static String htmlDocumentContent = HelperUtils.getRandomString(32,
false);
// request codes
private static final String OPTIONS = "OPTIONS";
private static final String GET = "GET";
private static final String HEAD = "HEAD";
private static final String POST = "POST";
private static final String PUT = "PUT";
private static final String DELETE = "DELETE";
private static final String TRACE = "TRACE";
private static final String CONNECT = "CONNECT";
private static final String STATUS_CODE_200 = "200 OK\r\n";
private static final String STATUS_CODE_400 = "400 Bad Request\r\n";
private static final String STATUS_CODE_505 = "505 HTTP Version not supported\r\n";
/**
* Sets the html document content for HTTP and HTTPS.
*
* @param htmlDocumentContent
*/
public static void setHtmlDocumentContent(String htmlDocumentContent) {
HTTP.htmlDocumentContent = htmlDocumentContent;
}
// html header pre and suffix
private String headerPrefix = "Date: " + getServerTime() + "\r\n"
+ "Server: " + serverVersion + " \r\n"
+ "Vary: Accept-Encoding\r\n" + "Content-Length: ";
private String headerSuffix = "\r\n" + "Keep-Alive: timeout=5, max=100\r\n"
+ "Connection: Keep-Alive\r\n" + "Content-Type: text/html\r\n"
+ "\r\n";
// html website
private String htmlDocument = "\n" + "\n"
+ "\n" + "\n" + ""
+ htmlDocumentContent + "\n" + ""
+ htmlDocumentContent + "\n" + "\n" + "";
// html error pre and suffix
private String errorHtmlPrefix = "\n"
+ "\n" + "\n"
+ "\n" + "";
private String errorHtmlSuffix = "\n" + "\n" + "";
@Override
public int getPort() {
return 80;
}
@Override
public boolean isClosed() {
return true;
}
@Override
public boolean isSecure() {
return false;
}
@Override
public List processMessage(Packet requestPacket) {
String request = null;
if (requestPacket != null) {
request = requestPacket.toString();
}
List responsePackets = new ArrayList();
this.request = request;
if (!request.contains(httpVersion)) {
responsePackets.add(buildPacket(STATUS_CODE_505, ""));
} else if (request.contains(GET)) {
responsePackets.add(buildPacket(STATUS_CODE_200, GET));
} else if (request.contains(HEAD)) {
responsePackets.add(buildPacket(STATUS_CODE_200, HEAD));
} else if (request.contains(TRACE)) {
responsePackets.add(buildPacket(STATUS_CODE_200, TRACE));
} else if (request.contains(OPTIONS)) {
responsePackets.add(buildPacket(STATUS_CODE_400, OPTIONS));
} else if (request.contains(POST)) {
responsePackets.add(buildPacket(STATUS_CODE_200, POST));
} else if (request.contains(PUT)) {
responsePackets.add(buildPacket(STATUS_CODE_400, PUT));
} else if (request.contains(DELETE)) {
responsePackets.add(buildPacket(STATUS_CODE_200, DELETE));
} else if (request.contains(CONNECT)) {
responsePackets.add(buildPacket(STATUS_CODE_400, CONNECT));
} else {
responsePackets.add(buildPacket(STATUS_CODE_400, ""));
}
return responsePackets;
}
@Override
public String toString() {
return "HTTP";
}
@Override
public TALK_FIRST whoTalksFirst() {
return TALK_FIRST.CLIENT;
}
/**
* Builds a html response that can be sent
*
* @param code
* response code that was determined
* @param type
* request type that was sent by the client
* @return the html response
*/
private Packet buildPacket(String code, String type) {
String document = "";
if (type.equals(GET)) {
document = htmlDocument;
} else if (type.equals(HEAD) || type.equals(DELETE)) {
document = "";
} else if (type.equals(TRACE)) {
document = request;
} else {
document = errorHtmlPrefix + " " + code + errorHtmlSuffix;
}
return new Packet(httpVersion + " " + code + headerPrefix
+ document.length() + headerSuffix + document);
}
}