juplo.de Git - fix-swf/blob - src/main/java/de/juplo/fixswf/FixSwfServlet.java

   1 package de.juplo.fixswf;
   2
   3 import java.io.IOException;
   4 import java.io.InputStream;
   5 import java.io.OutputStream;
   6 import java.io.PrintWriter;
   7 import java.util.HashMap;
   8 import java.util.Map;
   9 import java.util.regex.Matcher;
  10 import java.util.regex.Pattern;
  11 import javax.servlet.ServletConfig;
  12 import javax.servlet.ServletException;
  13 import javax.servlet.http.HttpServlet;
  14 import javax.servlet.http.HttpServletRequest;
  15 import javax.servlet.http.HttpServletResponse;
  16 import org.apache.commons.fileupload.FileItemIterator;
  17 import org.apache.commons.fileupload.FileItemStream;
  18 import org.apache.commons.fileupload.servlet.ServletFileUpload;
  19 import org.apache.commons.lang.StringEscapeUtils;
  20
  21 /**
  22  *
  23  * @author kai
  24  */
  25 public class FixSwfServlet extends HttpServlet
  26 {
  27   public final String MESSAGE_ATTRIBUTE = getClass().getCanonicalName() + ".MESSAGE";
  28
  29   private Map<Byte,Byte> corrections;
  30   private Pattern pattern;
  31
  32
  33   @Override
  34   public void init(ServletConfig config) throws ServletException {
  35     corrections = new HashMap<Byte,Byte>();
  36     corrections.put((byte)12, (byte)10);
  37     corrections.put((byte)14, (byte)11);
  38     pattern = Pattern.compile("([^/\\\\:<>?\"]+?)(?:\\.swf)?$", Pattern.MULTILINE | Pattern.CASE_INSENSITIVE);
  39   }
  40
  41
  42   /**
  43    * Processes requests for both HTTP
  44    * <code>GET</code> and
  45    * <code>POST</code> methods.
  46    *
  47    * @param request servlet request
  48    * @param response servlet response
  49    * @throws ServletException if a servlet-specific error occurs
  50    * @throws IOException if an I/O error occurs
  51    */
  52   protected void processRequest(
  53       HttpServletRequest request,
  54       HttpServletResponse response
  55     )
  56     throws
  57       ServletException,
  58       IOException
  59   {
  60     response.sendError(HttpServletResponse.SC_NOT_IMPLEMENTED);
  61   }
  62
  63   /**
  64    * Handles the HTTP
  65    * <code>GET</code> method.
  66    *
  67    * @param request servlet request
  68    * @param response servlet response
  69    * @throws ServletException if a servlet-specific error occurs
  70    * @throws IOException if an I/O error occurs
  71    */
  72   @Override
  73   protected void doGet(
  74       HttpServletRequest request,
  75       HttpServletResponse response
  76     )
  77     throws
  78       ServletException,
  79       IOException
  80   {
  81     response.setContentType("text/html;charset=UTF-8");
  82     PrintWriter out = response.getWriter();
  83     try
  84     {
  85       out.println("<html>");
  86       out.println("<head>");
  87       out.println("<title>Fix-Swf</title>");
  88       out.println("</head>");
  89       out.println("<body>");
  90       if (request.getAttribute(MESSAGE_ATTRIBUTE) != null)
  91       {
  92         out.println("<h1>Upload-Results</h1>");
  93         out.println("<p>" + StringEscapeUtils.escapeHtml((String)request.getAttribute(MESSAGE_ATTRIBUTE)) + "</p>");
  94       }
  95       out.println("<h1>Choose SWF-File to check/fix</h1>");
  96       out.println("<p>If the file has to be fixed, the fixed version will be presented to you as a download.</p>");
  97       out.println("<form action=\"\" method=\"post\" enctype=\"multipart/form-data\">");
  98       out.println("<input type=\"file\" name=\"swf\" />");
  99       out.println("<input type=\"submit\" name=\"submit\" value=\"Start Upload\" />");
 100       out.println("</form>");
 101       out.println("</body>");
 102       out.println("</html>");
 103     }
 104     finally
 105     {
 106       out.close();
 107     }
 108   }
 109
 110   /**
 111    * Handles the HTTP
 112    * <code>POST</code> method.
 113    *
 114    * @param request servlet request
 115    * @param response servlet response
 116    * @throws ServletException if a servlet-specific error occurs
 117    * @throws IOException if an I/O error occurs
 118    */
 119   @Override
 120   protected void doPost(
 121       HttpServletRequest request,
 122       HttpServletResponse response
 123     )
 124     throws
 125       ServletException,
 126       IOException
 127   {
 128     // Check that we have a file upload request
 129     if (!ServletFileUpload.isMultipartContent(request))
 130     {
 131       request.setAttribute(MESSAGE_ATTRIBUTE, "No data uploaded!");
 132       request.getRequestDispatcher("/").forward(request, response);
 133       return;
 134     }
 135
 136     // Create a new file upload handler
 137     ServletFileUpload upload = new ServletFileUpload();
 138
 139     try
 140     {
 141       // Parse the request
 142       FileItemIterator iter = upload.getItemIterator(request);
 143
 144       while(iter.hasNext())
 145       {
 146         FileItemStream item = iter.next();
 147
 148         if (item.isFormField())
 149           continue;
 150
 151         if (!item.getFieldName().equals("swf"))
 152           continue;
 153
 154         String filename = item.getName();
 155         InputStream in = item.openStream();
 156         byte[] buffer = new byte[512];
 157         int i;
 158         i = in.read(buffer);
 159
 160         if (i < 4)
 161         {
 162           request.setAttribute(MESSAGE_ATTRIBUTE, "Not enough data uploaded!");
 163           request.getRequestDispatcher("/").forward(request, response);
 164           return;
 165         }
 166
 167         if (!corrections.containsKey(buffer[3]))
 168         {
 169           request.setAttribute(MESSAGE_ATTRIBUTE, "Uploaded SWF-file " + filename + " was valid!");
 170           request.getRequestDispatcher("/").forward(request, response);
 171           return;
 172         }
 173
 174         /** Correct the Flash-Player-Version in Header-Byte 4 */
 175         buffer[3] = corrections.get(buffer[3]);
 176
 177         Matcher matcher = pattern.matcher(filename);
 178         if (matcher.matches())
 179         {
 180           filename = matcher.group(1) + "_FIXED.swf";
 181         }
 182         else
 183         {
 184           filename = "FIXED.swf";
 185         }
 186
 187         response.setHeader("Content-Type", "application/x-shockwave-flash");
 188         response.setHeader("Content-Disposition","attachment; filename=\"" + filename + "\"");
 189         OutputStream out = response.getOutputStream();
 190         do
 191         {
 192           out.write(buffer, 0, i);
 193         }
 194         while ((i = in.read(buffer)) > -1);
 195
 196         out.close();
 197       }
 198     }
 199     catch (Exception e)
 200     {
 201       request.setAttribute(MESSAGE_ATTRIBUTE, "Error while parsing upload: " + e);
 202       request.getRequestDispatcher("/").forward(request, response);
 203       return;
 204     }
 205
 206     /** Fallback, if no data was found (happens when forwarding!) */
 207     doGet(request, response);
 208   }
 209
 210   /**
 211    * Returns a short description of the servlet.
 212    *
 213    * @return a String containing servlet description
 214    */
 215   @Override
 216   public String getServletInfo() {
 217     return "This Servlet fixes the 4th byte of an uploaded SWF-file according to the SWF-filestructre specification.";
 218   }
 219 }