AirBears Automatic Login in Java

airbearsautologin.java

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

class AirBearsAutoLogin {

	// Published URLs that SHOULD not change.
	public static String google = "http://www.google.com/generate_204";
	public static String airbears = "https://wlan.berkeley.edu/cgi-bin/login/calnet.cgi";
	public static String calcas = "auth.berkeley.edu/cas/";
	private static String username = "rogerhub";
	private static String password = "";
	private static ArrayList<String[]> wlancookies = new ArrayList<String[]>();

	public static StringBuffer responseText;

	public static void main(String[] args) {
		
		System.out.println("===================================");
		System.out.println("| AirBears Automatic Login (Java) |");
		System.out.println("===================================\n");
		
		// Determine where we're at
		HttpURLConnection connection = checkGoogle(); // Requests: Google
		System.out.println("It looks like we are currently: " + checkStatus(connection));
		if (checkStatus(connection).equals("airbears")) {
			System.out.println("The portal redirects us to:\n  " + getRedirectTarget(connection));
		} else {
			System.out.println("There's nothing left to do! I'm exiting now.");
			return;
		}

		System.out.println();

		String cookieHeader;
		System.out.println("Requesting login using wlan.berkeley.edu. Connecting to:\n  " + getRedirectTarget(connection));
		openHTTP(getRedirectTarget(connection), "", false, false, false); // Requests: wlan
		if ((cookieHeader = getHeader(connection, "Set-Cookie")) != null) {
			assimilateCookies(cookieHeader);
		}
		
		System.out.println();

		// Try Airbears
		System.out.println("Requesting automated WLAN Login through CalNet.");
		connection = checkAirbears(); // Requests: wlan
		
		// Some sanity checks
		String authtarget = getRedirectTarget(connection);
		System.out.println("CAS redirects to:\n  " + authtarget);
		if (authtarget == null || authtarget.toLowerCase().indexOf(calcas) == -1) {
			System.out.println("It looks like there's nothing left to do! I'm exiting now.");
			return;
		}
		if ((cookieHeader = getHeader(connection, "Set-Cookie")) != null) {
			assimilateCookies(cookieHeader);
		}

		System.out.println();

		connection = openHTTP(authtarget, "", false, false, false); // Requests: auth
		System.out.println(getHeader(connection, "Set-Cookie", true));
		System.out.println("Cookie parsed was: " + getCookiePart(getHeader(connection, "Set-Cookie")));

		String params = "lt=" + encodeParam(getInputValueByName("lt"));
		params += "&_eventId=" + encodeParam(getInputValueByName("_eventId"));
		params += "&username=" + encodeParam(username);
		params += "&password=" + encodeParam(password);
		
		authtarget = "https://auth.berkeley.edu" + getTagAttrByAttr("loginForm", "form", "id", "action");
		
		System.out.println("Parameters prepared! Attempting to open connection to:\n  " + authtarget);
		connection = openHTTP(authtarget, params, false, false, true);

		System.out.println();

		try {
			int httpresponse = connection.getResponseCode();
			if (httpresponse == 200) {
				System.out.println("Looks like the authentication failed. Time to quit!");
				return;
			} else if (httpresponse != 302 && httpresponse != 301) {
				System.out.println("Looks like the authentication failed. Time to quit!");
				return;
			}
		} catch (Exception e) {
			System.out.println("Looks like the authentication failed. Time to quit!");
			return;
		}
		
		System.out.println("\n  Successful authentication attempt!\n");
		System.out.println("Attempting final auth: " + authtarget);
		authtarget = getRedirectTarget(connection);
		connection = openHTTP(authtarget, "", false, false, false);
		if ((cookieHeader = getHeader(connection, "Set-Cookie")) != null) {
			assimilateCookies(cookieHeader);
		}
		
		System.out.println("Redirected to: " + authtarget);
		authtarget = getRedirectTarget(connection);
		openHTTP(authtarget, "", false, false, false);
		
		System.out.println();
		System.out.println("All done! Have fun on the Internet.");
	}
	private static HttpURLConnection checkAirbears() {
		HttpURLConnection connection = 	openHTTP(airbears + "?submit=CalNet&url=" + encodeParam(google), "", false, false);
		System.out.println("Received response code: " + connection.getHeaderField(0));
		return connection;
	}
	private static HttpURLConnection checkGoogle() {
		HttpURLConnection connection = 	openHTTP(google, "", false, false);
		System.out.println("Received response code: " + connection.getHeaderField(0));
		return connection;
	}

	private static void assimilateCookies(String cookieHeader) {
		System.out.println("Assimilating cookies from:\n  " + cookieHeader);
		String[] cookieHeaders = cookieHeader.split("\n");
		int i;
		for (i = 0; i < cookieHeaders.length; i++) {
			if (cookieHeaders[i].trim().equals("")) {
				continue;
			}
			String[] cookieSet = new String[2];
			cookieSet[0] = getCookiePart(cookieHeaders[i], "key");
			cookieSet[1] = getCookiePart(cookieHeaders[i], "content");
			wlancookies.add(cookieSet);
		}
	}
	private static String cookieString() {
		String cookies = "";
		for (String[] cookieSet : wlancookies) {
			if (!cookies.equals("")) {
				cookies += "&";
			}
			cookies += encodeParam(cookieSet[0]) + "=" + encodeParam(cookieSet[1]);
		}
		return cookies;
	}

	private static String checkStatus(HttpURLConnection connection) {
		try {
			int httpresponse = connection.getResponseCode();
			if (httpresponse == 204) {
				return "connected";
			} else if (httpresponse == 302 || httpresponse == 301) {
				return "airbears";
			} else if (httpresponse == 200) {
				return "unknown";
			} else {
				return "fuckfuck";
			}
		} catch (IOException e) {
			e.printStackTrace();
			return null;
		}
	}
	private static String getRedirectTarget(HttpURLConnection connection) {
		String target;
		if ((target = getHeader(connection, "Location")) != null) {
			return target;
		} else {
			return target; // hahaha
		}
	}
	private static String getHeader(HttpURLConnection connection) {
		return getHeader(connection, "", true);
	}
	private static String getHeader(HttpURLConnection connection, String headerKey) {
		return getHeader(connection, headerKey, false);
	}
	private static String getHeader(HttpURLConnection connection, String headerKey, boolean printDebug) {
		int i = 1;
		String key;
		while ((key = connection.getHeaderFieldKey(i)) != null) {
			if (printDebug) {
				System.out.println("\tGot header -- " + key + ": " + connection.getHeaderField(i));
			}
			if (key.equalsIgnoreCase(headerKey)) {
				return connection.getHeaderField(i);
			} else {
				i += 1;
			}
		}
		return null;
	}
	
	public static String encodeParam(String param) {
		try {
			return URLEncoder.encode(param, "UTF-8");
		} catch (Exception e) {
			return "";
		}
	}
	public static String getCookiePart(String cookie) {
		return getCookiePart(cookie, "content");
	}
	public static String getCookiePart(String cookie, String part) {
		String[] cookieparts = cookie.split(";");
		if (part.equals("content") || part.equals("key")) {
			String[] partparts = cookieparts[0].split("=");
			if (part.equals("content")) {
				return partparts[1].trim();
			} else {
				return partparts[0].trim();			
			}
		}
		int i;
		for (i = 1; i < cookieparts.length; i++) {
			String[] partparts = cookieparts[i].split("=");
			if (partparts[0].trim().equals(part)) {
				return partparts[1].trim();
			}
		}
		return null;
	}
	private static String getInputValueByName(String name) {
		return getTagValueByName(name, "input");
	}
	private static String getTagValueByName(String name, String tagname) {
		return getTagValueByAttr(name, tagname, "name");
	}
	private static String getTagValueByAttr(String name, String tagname, String attr) {
		return getTagAttrByAttr(name, tagname, attr, "value");
	}
	private static String getTagAttrByAttr(String name, String tagname, String attr, String targetattr) {
		Matcher m = Pattern.compile("<" + tagname + "[^>]+>").matcher(responseText);
		String tag;
		while (m.find()) {
			tag = m.group();
			Matcher name_match = Pattern.compile(attr + "=\"([^\"]+)\"").matcher(tag);
			if (name_match.find()) { // Only first result
				System.out.println("match!" + name_match.group());
				if (name_match.group(1).trim().toLowerCase().equals(name.toLowerCase())) {
					Matcher value_match = Pattern.compile(targetattr + "=\"([^\"]+)\"").matcher(tag);
					if (value_match.find()) {
						return value_match.group(1);
					}
				}
			}
		}
		return "";
	}

	public static HttpURLConnection openHTTP(String targetUrl, String urlParameters) {
		return openHTTP(targetUrl, urlParameters, true);	
	}
	public static HttpURLConnection openHTTP(String targetUrl, String urlParameters, boolean followRedirect) {
		return openHTTP(targetUrl, urlParameters, followRedirect, true);
	}
	public static HttpURLConnection openHTTP(String targetUrl, String urlParameters, boolean followRedirect, boolean useCache) {
		return openHTTP(targetUrl, urlParameters, followRedirect, useCache, false);
	}
	public static HttpURLConnection openHTTP(String targetUrl, String urlParameters, boolean followRedirect, boolean useCache, boolean usePost) {
		URL url;
		HttpURLConnection connection = null;
		try {
			
			url = new URL(targetUrl); // Reuse, yes I know.

			connection = (HttpURLConnection) url.openConnection();
			connection.setRequestMethod(usePost ? "POST" : "GET");
			if (usePost) {
				connection.setRequestProperty("Content-Length", Integer.toString(urlParameters.getBytes().length));
			}
			String cookies;
			if ((cookies = cookieString()) != "") {
				connection.setRequestProperty("Cookie", cookieString());
			}
			
			connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.97 Safari/537.11");
			connection.setInstanceFollowRedirects(followRedirect);
			connection.setUseCaches(useCache);
			connection.setDoInput(true);
			connection.setDoOutput(true);

			if (usePost) {
				DataOutputStream wr = new DataOutputStream(connection.getOutputStream());
				wr.writeBytes(urlParameters);
				wr.flush();
				wr.close();
			}

			InputStream is = connection.getInputStream();
			BufferedReader rd = new BufferedReader(new InputStreamReader(is));
			
			String line;
			responseText = new StringBuffer();
			while ((line = rd.readLine()) != null) {
				responseText.append(line);
				responseText.append('\n');
			}
			
			rd.close();

			return connection;
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if (connection != null) {
				connection.disconnect();
			}
		}
		return null;
	}
}