PDF-AS web Developments

4 files changed, 633 insertions, 62 deletions

diff --git a/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/HTMLFormater.java b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/HTMLFormater.java
new file mode 100644
index 00000000..fe2c9271
--- /dev/null
+++ b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/HTMLFormater.java
@@ -0,0 +1,13 @@
+package at.gv.egiz.pdfas.web.helper;
+
+public class HTMLFormater {
+
+	public static String formatStackTrace(StackTraceElement[] elements) {
+		StringBuilder sb = new StringBuilder();
+		for(int i = 0; i < elements.length; i++) {
+			sb.append(elements[i].toString());
+			sb.append("</br>");
+		}
+		return sb.toString();
+	}
+}
diff --git a/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsHelper.java b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsHelper.java
index 154cfd01..daf18108 100644
--- a/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsHelper.java
+++ b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsHelper.java
@@ -5,6 +5,9 @@ import java.io.IOException;
 import java.util.Iterator;
 import java.util.List;
 
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
@@ -12,14 +15,29 @@ import javax.xml.bind.JAXBElement;
 
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.lang3.StringEscapeUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
+import com.lowagie.text.html.WebColors;
+
+import at.gv.egiz.pdfas.lib.api.ByteArrayDataSink;
 import at.gv.egiz.pdfas.lib.api.ByteArrayDataSource;
 import at.gv.egiz.pdfas.lib.api.Configuration;
+import at.gv.egiz.pdfas.lib.api.DataSink;
 import at.gv.egiz.pdfas.lib.api.PdfAs;
 import at.gv.egiz.pdfas.lib.api.PdfAsFactory;
+import at.gv.egiz.pdfas.lib.api.SignaturePosition;
 import at.gv.egiz.pdfas.lib.api.StatusRequest;
+import at.gv.egiz.pdfas.lib.api.sign.IPlainSigner;
 import at.gv.egiz.pdfas.lib.api.sign.SignParameter;
+import at.gv.egiz.pdfas.lib.api.sign.SignResult;
+import at.gv.egiz.pdfas.lib.impl.PdfAsImpl;
+import at.gv.egiz.pdfas.lib.impl.SignaturePositionImpl;
 import at.gv.egiz.pdfas.sigs.pades.PAdESSigner;
+import at.gv.egiz.pdfas.sigs.pades.PAdESSignerKeystore;
+import at.gv.egiz.pdfas.sigs.pkcs7detached.PKCS7DetachedSigner;
+import at.gv.egiz.pdfas.web.config.WebConfiguration;
+import at.gv.egiz.pdfas.web.exception.PdfAsWebException;
 import at.gv.egiz.sl.CreateCMSSignatureRequestType;
 import at.gv.egiz.sl.CreateCMSSignatureResponseType;
 import at.gv.egiz.sl.InfoboxAssocArrayPairType;
@@ -27,6 +45,7 @@ import at.gv.egiz.sl.InfoboxReadRequestType;
 import at.gv.egiz.sl.InfoboxReadResponseType;
 import at.gv.egiz.sl.ObjectFactory;
 import at.gv.egiz.sl.util.BKUSLConnector;
+import at.gv.egiz.sl.util.MOAConnector;
 import at.gv.egiz.sl.util.SLMarschaller;
 
 public class PdfAsHelper {
@@ -34,32 +53,240 @@ public class PdfAsHelper {
 	private static final String PDF_CONFIG = "PDF_CONFIG";
 	private static final String PDF_STATUS = "PDF_STATUS";
 	private static final String PDF_SL_CONNECTOR = "PDF_SL_CONNECTOR";
+	private static final String PDF_SIGNER = "PDF_SIGNER";
+	private static final String PDF_SL_INTERACTIVE = "PDF_SL_INTERACTIVE";
+	private static final String PDF_SIGNED_DATA = "PDF_SIGNED_DATA";
+	private static final String PDF_ERR_MESSAGE = "PDF_ERR_MESSAGE";
+	private static final String PDF_ERR_THROWABLE = "PDF_ERR_THROWABLE";
+	private static final String PDF_ERROR_PAGE = "/ErrorPage";
+	private static final String PDF_PROVIDE_PAGE = "/ProvidePDF";
+	private static final String PDF_PDFDATA_PAGE = "/PDFData";
+	private static final String PDF_DATAURL_PAGE = "/DataURL";
+	private static final String PDF_ERR_URL = "PDF_ERR_URL";
+	private static final String PDF_INVOKE_URL = "PDF_INVOKE_URL";
+	private static final String REQUEST_FROM_DU = "REQ_DATA_URL";
+
+	// For development only:
+	public static final String keyStoreFile = "/home/afitzek/devel/pdfas_neu/test.p12";
+	public static final String keyStoreType = "PKCS12";
+	public static final String keyStorePass = "123456";
+	// public static final String keyAlias = "pdf";
+	public static final String keyAlias = "ecc_test";
+	public static final String keyPass = "123456";
+
+	private static final Logger logger = LoggerFactory
+			.getLogger(PdfAsHelper.class);
 
 	private static PdfAs pdfAs;
 	private static ObjectFactory of = new ObjectFactory();
 
 	static {
+		// TODO: read from config file
+		logger.debug("Creating PDF-AS");
 		pdfAs = PdfAsFactory.createPdfAs(new File("/home/afitzek/.pdfas"));
+		logger.debug("Creating PDF-AS done");
 	}
 
-	public static void startSignature(HttpServletRequest request,
+	private static void validatePdfSize(HttpServletRequest request,
+			HttpServletResponse response, byte[] pdfData)
+			throws PdfAsWebException {
+		// Try to check num-bytes
+		String pdfSizeString = PdfAsParameterExtractor.getNumBytes(request);
+		if (pdfSizeString != null) {
+			long pdfSize = -1;
+			try {
+				pdfSize = Long.parseLong(pdfSizeString);
+			} catch (NumberFormatException e) {
+				throw new PdfAsWebException(
+						PdfAsParameterExtractor.PARAM_NUM_BYTES
+								+ " parameter has to be a positiv number!", e);
+			}
+			if (pdfSize <= 0) {
+				throw new PdfAsWebException(
+						"Invalid PDF Size! Has to bigger than zero!");
+			}
+
+			if (pdfData.length != pdfSize) {
+				throw new PdfAsWebException("Signature Data Size and "
+						+ PdfAsParameterExtractor.PARAM_NUM_BYTES
+						+ " missmatch!");
+			}
+		}
+	}
+
+	private static String buildPosString(HttpServletRequest request,
+			HttpServletResponse response) throws PdfAsWebException {
+		String posP = PdfAsParameterExtractor.getSigPosP(request);
+		String posX = PdfAsParameterExtractor.getSigPosX(request);
+		String posY = PdfAsParameterExtractor.getSigPosY(request);
+		String posW = PdfAsParameterExtractor.getSigPosW(request);
+
+		if (posP == null && posW == null && posX == null && posY == null) {
+			return null;
+		}
+
+		StringBuilder sb = new StringBuilder();
+
+		if (posX != null) {
+			try {
+				Float.parseFloat(posX);
+			} catch (NumberFormatException e) {
+				throw new PdfAsWebException(
+						PdfAsParameterExtractor.PARAM_SIG_POS_X
+								+ " has invalid value!", e);
+			}
+			sb.append("x:" + posX.trim() + ";");
+		} else {
+			sb.append("x:auto;");
+		}
+
+		if (posY != null) {
+			try {
+				Float.parseFloat(posY);
+			} catch (NumberFormatException e) {
+				throw new PdfAsWebException(
+						PdfAsParameterExtractor.PARAM_SIG_POS_Y
+								+ " has invalid value!", e);
+			}
+			sb.append("y:" + posY.trim() + ";");
+		} else {
+			sb.append("y:auto;");
+		}
+
+		if (posW != null) {
+			try {
+				Float.parseFloat(posW);
+			} catch (NumberFormatException e) {
+				throw new PdfAsWebException(
+						PdfAsParameterExtractor.PARAM_SIG_POS_W
+								+ " has invalid value!", e);
+			}
+			sb.append("w:" + posW.trim() + ";");
+		} else {
+			sb.append("w:auto;");
+		}
+
+		if (posP != null) {
+			if (!(posP.equals("auto") || posP.equals("new"))) {
+				throw new PdfAsWebException(
+						PdfAsParameterExtractor.PARAM_SIG_POS_P
+								+ " has invalid value! (auto | new )");
+			}
+			sb.append("p:" + posP.trim() + ";");
+		} else {
+			sb.append("P:auto;");
+		}
+
+		return sb.toString();
+	}
+
+	public static void doSignature(HttpServletRequest request,
+			HttpServletResponse response, byte[] pdfData) throws Exception {
+
+	}
+
+	/**
+	 * Create synchronous PDF Signature
+	 * 
+	 * @param request
+	 *            The Web request
+	 * @param response
+	 *            The Web response
+	 * @param pdfData
+	 *            The pdf data
+	 * @return The signed pdf data
+	 * @throws Exception
+	 */
+	public static byte[] synchornousSignature(HttpServletRequest request,
 			HttpServletResponse response, byte[] pdfData) throws Exception {
+		validatePdfSize(request, response, pdfData);
+
+		Configuration config = pdfAs.getConfiguration();
+
+		// Generate Sign Parameter
+		SignParameter signParameter = PdfAsFactory.createSignParameter(config,
+				new ByteArrayDataSource(pdfData));
+
+		// Get Connector
+		String connector = PdfAsParameterExtractor.getConnector(request);
+
+		if (!connector.equals("moa") && !connector.equals("jks")) {
+			throw new PdfAsWebException("Invalid connector (moa | jks)");
+		}
+
+		IPlainSigner signer;
+		if (connector.equals("moa")) {
+			signer = new PAdESSigner(new MOAConnector(config));
+		} else {
+			// TODO:
+			// signer = new PAdESSignerKeystore(file, alias, kspassword,
+			// keypassword, type)
+			signer = new PKCS7DetachedSigner(keyStoreFile, keyAlias,
+					keyStorePass, keyPass, keyStoreType);
+		}
+
+		signParameter.setPlainSigner(signer);
+
+		// set Signature Profile (null use default ...)
+		signParameter.setSignatureProfileId(PdfAsParameterExtractor
+				.getSigType(request));
+
+		ByteArrayDataSink output = new ByteArrayDataSink();
+		signParameter.setOutput(output);
+
+		// set Signature Position
+		signParameter.setSignaturePosition(buildPosString(request, response));
+
+		pdfAs.sign(signParameter);
+
+		return output.getData();
+	}
+
+	public static void startSignature(HttpServletRequest request,
+			HttpServletResponse response, ServletContext context, byte[] pdfData)
+			throws Exception {
+
+		validatePdfSize(request, response, pdfData);
 
 		HttpSession session = request.getSession();
 
 		Configuration config = pdfAs.getConfiguration();
 		session.setAttribute(PDF_CONFIG, config);
-		BKUSLConnector bkuSLConnector = new BKUSLConnector(config);
+
+		// Generate Sign Parameter
 		SignParameter signParameter = PdfAsFactory.createSignParameter(config,
 				new ByteArrayDataSource(pdfData));
-		signParameter.setPlainSigner(new PAdESSigner(bkuSLConnector));
-		
-		session.setAttribute(PDF_SL_CONNECTOR, bkuSLConnector);
+
+		// Get Connector
+		String connector = PdfAsParameterExtractor.getConnector(request);
+
+		IPlainSigner signer;
+		if (connector.equals("bku") || connector.equals("onlinebku") || connector.equals("mobilebku")) {
+			BKUSLConnector conn = new BKUSLConnector(config);
+			signer = new PAdESSigner(conn);
+			session.setAttribute(PDF_SL_CONNECTOR, conn);
+		} else {
+			throw new PdfAsWebException("Invalid connector (bku | onlinebku | mobilebku | moa | jks)");
+		}
+
+		signParameter.setPlainSigner(signer);
+		session.setAttribute(PDF_SIGNER, signer);
+		session.setAttribute(PDF_SL_INTERACTIVE, connector);
+
+		// set Signature Profile (null use default ...)
+		signParameter.setSignatureProfileId(PdfAsParameterExtractor
+				.getSigType(request));
+
+		ByteArrayDataSink dataSink = new ByteArrayDataSink();
+		signParameter.setOutput(dataSink);
+
+		// set Signature Position
+		signParameter.setSignaturePosition(buildPosString(request, response));
 
 		StatusRequest statusRequest = pdfAs.startSign(signParameter);
 		session.setAttribute(PDF_STATUS, statusRequest);
 
-		PdfAsHelper.process(request, response);
+		PdfAsHelper.process(request, response, context);
 	}
 
 	private static byte[] getCertificate(
@@ -69,36 +296,40 @@ public class PdfAsHelper {
 			List<InfoboxAssocArrayPairType> pairs = infoboxReadResponseType
 					.getAssocArrayData().getPair();
 			Iterator<InfoboxAssocArrayPairType> pairIterator = pairs.iterator();
-			while(pairIterator.hasNext()) {
+			while (pairIterator.hasNext()) {
 				InfoboxAssocArrayPairType pair = pairIterator.next();
-				if(pair.getKey().equals("SecureSignatureKeypair")) {
+				if (pair.getKey().equals("SecureSignatureKeypair")) {
 					return pair.getBase64Content();
 				}
 			}
 		}
 		// SecureSignatureKeypair
-		
+
 		return data;
 	}
 
 	public static void injectCertificate(HttpServletRequest request,
-			HttpServletResponse response, 
-			InfoboxReadResponseType infoboxReadResponseType) throws Exception {
-		
+			HttpServletResponse response,
+			InfoboxReadResponseType infoboxReadResponseType,
+			ServletContext context) throws Exception {
+
 		HttpSession session = request.getSession();
-		StatusRequest statusRequest = (StatusRequest)session.getAttribute(PDF_STATUS);
-		
+		StatusRequest statusRequest = (StatusRequest) session
+				.getAttribute(PDF_STATUS);
+
 		statusRequest.setCertificate(getCertificate(infoboxReadResponseType));
 		statusRequest = pdfAs.process(statusRequest);
 		session.setAttribute(PDF_STATUS, statusRequest);
-		
-		PdfAsHelper.process(request, response);
+
+		PdfAsHelper.process(request, response, context);
 	}
 
 	public static void injectSignature(HttpServletRequest request,
 			HttpServletResponse response,
-			CreateCMSSignatureResponseType createCMSSignatureResponseType)
-			throws Exception {
+			CreateCMSSignatureResponseType createCMSSignatureResponseType,
+			ServletContext context) throws Exception {
+
+		logger.info("Got CMS Signature Response");
 
 		HttpSession session = request.getSession();
 		StatusRequest statusRequest = (StatusRequest) session
@@ -109,58 +340,88 @@ public class PdfAsHelper {
 		statusRequest = pdfAs.process(statusRequest);
 		session.setAttribute(PDF_STATUS, statusRequest);
 
-		PdfAsHelper.process(request, response);
+		PdfAsHelper.process(request, response, context);
 	}
 
 	public static void process(HttpServletRequest request,
-			HttpServletResponse response) throws Exception {
+			HttpServletResponse response, ServletContext context)
+			throws Exception {
 
 		HttpSession session = request.getSession();
 		StatusRequest statusRequest = (StatusRequest) session
 				.getAttribute(PDF_STATUS);
-		BKUSLConnector bkuSLConnector = (BKUSLConnector) session
-				.getAttribute(PDF_SL_CONNECTOR);
-		Configuration config = (Configuration) session.getAttribute(PDF_CONFIG);
-
-		if (statusRequest.needCertificate()) {
-			// build SL Request to read certificate
-			InfoboxReadRequestType readCertificateRequest = bkuSLConnector
-					.createInfoboxReadRequest();
-
-			JAXBElement<InfoboxReadRequestType> readRequest = of
-					.createInfoboxReadRequest(readCertificateRequest);
-
-			String url = request.getContextPath() + "/DataURL;jsessionid="
-					+ session.getId();
-			String fullurl = request.getScheme() + "://"
-					+ request.getServerName() + ":" + request.getServerPort()
-					+ url;
-			String slRequest = SLMarschaller.marshalToString(readRequest);
-			String template = getTemplateSL();
-			template = template.replace("##BKU##",
-					"http://127.0.0.1:3495/http-security-layer-request");
-			template = template.replace("##XMLRequest##",
-					StringEscapeUtils.escapeHtml4(slRequest));
-			template = template.replace("##DataURL##", fullurl);
-			response.getWriter().write(template);
-			response.getWriter().close();
-		} else if (statusRequest.needSignature()) {
-			// build SL Request for cms signature
-			CreateCMSSignatureRequestType createCMSSignatureRequestType = 
-					bkuSLConnector.createCMSRequest(statusRequest.getSignatureData(), 
-							statusRequest.getSignatureDataByteRange());
-			
-			String slRequest = SLMarschaller.marshalToString(of
-						.createCreateCMSSignatureRequest(createCMSSignatureRequestType));
-			
-			response.setContentType("text/xml");
-			response.getWriter().write(slRequest);
-			response.getWriter().close();
-			
-		} else if (statusRequest.isReady()) {
-			// TODO: store pdf document redirect to Finish URL
+		IPlainSigner plainSigner = (IPlainSigner) session
+				.getAttribute(PDF_SIGNER);
+
+		String connector = (String) session.getAttribute(PDF_SL_INTERACTIVE);
+
+		if (connector.equals("bku") || connector.equals("onlinebku") || connector.equals("mobilebku")) {
+			BKUSLConnector bkuSLConnector = (BKUSLConnector) session
+					.getAttribute(PDF_SL_CONNECTOR);
+
+			// TODO Handle logic for BKU interaction
+
+			Configuration config = (Configuration) session
+					.getAttribute(PDF_CONFIG);
+
+			if (statusRequest.needCertificate()) {
+				logger.info("Needing Certificate from BKU");
+				// build SL Request to read certificate
+				InfoboxReadRequestType readCertificateRequest = bkuSLConnector
+						.createInfoboxReadRequest();
+
+				JAXBElement<InfoboxReadRequestType> readRequest = of
+						.createInfoboxReadRequest(readCertificateRequest);
+
+				String url = request.getContextPath() + "/DataURL;jsessionid="
+						+ session.getId();
+				String fullurl = request.getScheme() + "://"
+						+ request.getServerName() + ":"
+						+ request.getServerPort() + url;
+				String slRequest = SLMarschaller.marshalToString(readRequest);
+				String template = getTemplateSL();
+				template = template.replace("##BKU##",
+						generateBKUURL(connector));
+				template = template.replace("##XMLRequest##",
+						StringEscapeUtils.escapeHtml4(slRequest));
+				template = template.replace("##DataURL##", fullurl);
+				response.getWriter().write(template);
+				response.getWriter().close();
+			} else if (statusRequest.needSignature()) {
+				logger.info("Needing Signature from BKU");
+				// build SL Request for cms signature
+				CreateCMSSignatureRequestType createCMSSignatureRequestType = bkuSLConnector
+						.createCMSRequest(statusRequest.getSignatureData(),
+								statusRequest.getSignatureDataByteRange());
+
+				String slRequest = SLMarschaller
+						.marshalToString(of
+								.createCreateCMSSignatureRequest(createCMSSignatureRequestType));
+
+				response.setContentType("text/xml");
+				response.getWriter().write(slRequest);
+				response.getWriter().close();
+
+			} else if (statusRequest.isReady()) {
+				// TODO: store pdf document redirect to Finish URL
+				logger.info("Document ready!");
+
+				SignResult result = pdfAs.finishSign(statusRequest);
+				DataSink output = result.getOutputDocument();
+				if (output instanceof ByteArrayDataSink) {
+					ByteArrayDataSink byteDataSink = (ByteArrayDataSink) output;
+					PdfAsHelper.setSignedPdf(request, response,
+							byteDataSink.getData());
+					PdfAsHelper.gotoProvidePdf(context, request, response);
+				} else {
+					// TODO: no signature data available!
+				}
+
+			} else {
+				// TODO: invalid state
+			}
 		} else {
-			// TODO: invalid state
+			// TODO Handle logic for
 		}
 	}
 
@@ -169,5 +430,187 @@ public class PdfAsHelper {
 				.toFile(PdfAsHelper.class.getResource("/template_sl.html")));
 		return xml;
 	}
+	
+	public static String getErrorRedirectTemplateSL() throws IOException {
+		String xml = FileUtils.readFileToString(FileUtils
+				.toFile(PdfAsHelper.class.getResource("/template_error_redirect.html")));
+		return xml;
+	}
+	
+	public static String getInvokeRedirectTemplateSL() throws IOException {
+		String xml = FileUtils.readFileToString(FileUtils
+				.toFile(PdfAsHelper.class.getResource("/template_invoke_redirect.html")));
+		return xml;
+	}
+
+	public static byte[] getSignedPdf(HttpServletRequest request,
+			HttpServletResponse response) {
+		HttpSession session = request.getSession();
+		Object signedData = session.getAttribute(PDF_SIGNED_DATA);
+		if (signedData == null) {
+			return null;
+		}
+
+		if (signedData instanceof byte[]) {
+			return (byte[]) signedData;
+		}
+		logger.warn("PDF_SIGNED_DATA in session is not a byte[] type!");
+		return null;
+	}
+
+	public static void setSignedPdf(HttpServletRequest request,
+			HttpServletResponse response, byte[] signedData) {
+		HttpSession session = request.getSession();
+		session.setAttribute(PDF_SIGNED_DATA, signedData);
+	}
+
+	public static void setSessionException(HttpServletRequest request,
+			HttpServletResponse response, String message, Throwable e) {
+		HttpSession session = request.getSession();
+		session.setAttribute(PDF_ERR_MESSAGE, message);
+		session.setAttribute(PDF_ERR_THROWABLE, e);
+	}
+
+	public static String getSessionErrMessage(HttpServletRequest request,
+			HttpServletResponse response) {
+		HttpSession session = request.getSession();
+		Object obj = session.getAttribute(PDF_ERR_MESSAGE);
+		return obj == null ? null : obj.toString();
+	}
+
+	public static Throwable getSessionException(HttpServletRequest request,
+			HttpServletResponse response) {
+		HttpSession session = request.getSession();
+		Object obj = session.getAttribute(PDF_ERR_THROWABLE);
+		if (obj == null) {
+			return null;
+		}
+
+		if (obj instanceof Throwable) {
+			return (Throwable) obj;
+		}
+		logger.warn("PDF_ERR_THROWABLE in session is not a throwable type!");
+		return null;
+	}
+
+	public static void gotoError(ServletContext context,
+			HttpServletRequest request, HttpServletResponse response)
+			throws ServletException, IOException {
+		if (PdfAsHelper.getFromDataUrl(request)) {
+			response.sendRedirect(generateErrorURL(request, response));
+		} else {
+			RequestDispatcher dispatcher = context
+					.getRequestDispatcher(PDF_ERROR_PAGE);
+			dispatcher.forward(request, response);
+		}
+	}
+
+	public static void gotoProvidePdf(ServletContext context,
+			HttpServletRequest request, HttpServletResponse response)
+			throws ServletException, IOException {
+		if (PdfAsHelper.getFromDataUrl(request)) {
+			response.sendRedirect(generateProvideURL(request, response));
+		} else {
+			RequestDispatcher dispatcher = context
+					.getRequestDispatcher(PDF_PROVIDE_PAGE);
+			dispatcher.forward(request, response);
+		}
+	}
+
+	public static void setErrorURL(HttpServletRequest request,
+			HttpServletResponse response, String url) {
+		HttpSession session = request.getSession();
+		session.setAttribute(PDF_ERR_URL, url);
+	}
+
+	public static String getErrorURL(HttpServletRequest request,
+			HttpServletResponse response) {
+		HttpSession session = request.getSession();
+		Object obj = session.getAttribute(PDF_ERR_URL);
+		return obj == null ? null : obj.toString();
+	}
+	
+	public static void setInvokeURL(HttpServletRequest request,
+			HttpServletResponse response, String url) {
+		HttpSession session = request.getSession();
+		session.setAttribute(PDF_INVOKE_URL, url);
+		logger.info("External Invoke URL: " + url);
+	}
+
+	public static String getInvokeURL(HttpServletRequest request,
+			HttpServletResponse response) {
+		HttpSession session = request.getSession();
+		Object obj = session.getAttribute(PDF_INVOKE_URL);
+		return obj == null ? null : obj.toString();
+	}
 
+	private static String generateURL(HttpServletRequest request,
+			HttpServletResponse response, String Servlet) {
+		HttpSession session = request.getSession();
+		String publicURL = WebConfiguration.getPublicURL();
+		String dataURL = null;
+		if (publicURL != null) {
+			dataURL = publicURL + Servlet + ";jsessionid=" + session.getId();
+		} else {
+			if ((request.getScheme().equals("http") && request.getServerPort() == 80)
+					|| (request.getScheme().equals("https") && request
+							.getServerPort() == 443)) {
+				dataURL = request.getScheme() + "://" + request.getServerName()
+						+ request.getContextPath() + Servlet + ";jsessionid="
+						+ session.getId();
+			} else {
+				dataURL = request.getScheme() + "://" + request.getServerName()
+						+ ":" + request.getServerPort()
+						+ request.getContextPath() + Servlet + ";jsessionid="
+						+ session.getId();
+			}
+		}
+		logger.info("Generated URL: " + dataURL);
+		return dataURL;
+	}
+	
+	public static String generateDataURL(HttpServletRequest request,
+			HttpServletResponse response) {
+		return generateURL(request, response, PDF_DATAURL_PAGE);
+	}
+
+	public static String generateProvideURL(HttpServletRequest request,
+			HttpServletResponse response) {
+		return generateURL(request, response, PDF_PROVIDE_PAGE);
+	}
+	
+	public static String generateErrorURL(HttpServletRequest request,
+			HttpServletResponse response) {
+		return generateURL(request, response, PDF_ERROR_PAGE);
+	}
+
+	public static String generatePdfURL(HttpServletRequest request,
+			HttpServletResponse response) {
+		return generateURL(request, response, PDF_PDFDATA_PAGE);
+	}
+	
+	public static String generateBKUURL(String connector) {
+		if(connector.equals("bku")) {
+			return WebConfiguration.getLocalBKUURL();
+		} else if(connector.equals("onlinebku")) {
+			return WebConfiguration.getOnlineBKUURL();
+		} else if(connector.equals("mobilebku")) {
+			return WebConfiguration.getHandyBKUURL();
+		}
+		return WebConfiguration.getLocalBKUURL();
+	}
+
+	public static void setFromDataUrl(HttpServletRequest request) {
+		request.setAttribute(REQUEST_FROM_DU, (Boolean) true);
+	}
+
+	public static boolean getFromDataUrl(HttpServletRequest request) {
+		Object obj = request.getAttribute(REQUEST_FROM_DU);
+		if (obj != null) {
+			if (obj instanceof Boolean) {
+				return ((Boolean) obj).booleanValue();
+			}
+		}
+		return false;
+	}
 }
diff --git a/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsParameterExtractor.java b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsParameterExtractor.java
new file mode 100644
index 00000000..5a79bb4a
--- /dev/null
+++ b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/PdfAsParameterExtractor.java
@@ -0,0 +1,85 @@
+package at.gv.egiz.pdfas.web.helper;
+
+import javax.servlet.http.HttpServletRequest;
+
+public class PdfAsParameterExtractor {
+
+	public static final String PARAM_CONNECTOR = "connector";
+	public static final String PARAM_CONNECTOR_DEFAULT = "bku";
+	
+	
+	public static final String PARAM_INVOKE_URL = "invoke-app-url";
+	public static final String PARAM_INVOKE_URL_ERROR = "invoke-app-error-url";
+	public static final String PARAM_LOCALE = "locale";
+	public static final String PARAM_NUM_BYTES = "num-bytes";
+	public static final String PARAM_PDF_URL = "pdf-url";
+	public static final String PARAM_SIG_TYPE = "sig_type";
+	public static final String PARAM_SIG_POS_P = "sig-pos-p";
+	public static final String PARAM_SIG_POS_Y = "sig-pos-y";
+	public static final String PARAM_SIG_POS_X = "sig-pos-x";
+	public static final String PARAM_SIG_POS_W = "sig-pos-w";
+	
+	public static String getConnector(HttpServletRequest request) {
+		String connector = (String)request.getAttribute(PARAM_CONNECTOR);
+		if(connector != null) {
+			return connector;
+		} 
+		return PARAM_CONNECTOR_DEFAULT;
+	}
+	
+	public static String getInvokeURL(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_INVOKE_URL);
+	}
+	
+	public static String getInvokeErrorURL(HttpServletRequest request) {
+		String url = (String)request.getAttribute(PARAM_INVOKE_URL_ERROR);
+		if(url != null) {
+			//TODO validation!
+		}
+		return url;
+	}
+	
+	public static String getLocale(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_LOCALE);
+	}
+	
+	public static String getNumBytes(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_NUM_BYTES);
+	}
+	
+	public static String getPdfUrl(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_PDF_URL);
+	}
+	
+	public static String getSigType(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_SIG_TYPE);
+	}
+	
+	public static String getSigPosP(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_SIG_POS_P);
+	}
+	
+	public static String getSigPosY(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_SIG_POS_Y);
+	}
+	
+	public static String getSigPosX(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_SIG_POS_X);
+	}
+	
+	public static String getSigPosW(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_SIG_POS_W);
+	}
+	
+	// legacy Parameter
+	public static final String PARAM_PDF_ID = "pdf-id";
+	public static final String PARAM_SESSION_ID = "session-id";
+	
+	public static String getPdfId(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_PDF_ID);
+	}
+	
+	public static String getSessionId(HttpServletRequest request) {
+		return (String)request.getAttribute(PARAM_SESSION_ID);
+	}
+}
diff --git a/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/RemotePDFFetcher.java b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/RemotePDFFetcher.java
new file mode 100644
index 00000000..7c90dbc8
--- /dev/null
+++ b/pdf-as-web/src/main/java/at/gv/egiz/pdfas/web/helper/RemotePDFFetcher.java
@@ -0,0 +1,30 @@
+package at.gv.egiz.pdfas.web.helper;
+
+import java.io.InputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import at.gv.egiz.pdfas.common.utils.StreamUtils;
+import at.gv.egiz.pdfas.web.exception.PdfAsWebException;
+
+public class RemotePDFFetcher {
+
+	public static byte[] fetchPdfFile(String pdfURL) throws PdfAsWebException {
+		URL url;
+		try {
+			url = new URL(pdfURL);
+		} catch (MalformedURLException e) {
+			throw new PdfAsWebException("Not a valid URL!", e);
+		}
+		if(url.getProtocol().equals("http") || url.getProtocol().equals("https")) {
+			try {
+				InputStream is = url.openStream();
+				return StreamUtils.inputStreamToByteArray(is);
+			} catch (Exception e) {
+				throw new PdfAsWebException("Failed to fetch pdf document!", e);
+			}
+		} else {
+			throw new PdfAsWebException("Failed to fetch pdf document protocol " + url.getProtocol() + " is not supported");
+		}
+	}
+}