rplantiko · August 15, 2016 07:53 · Aug 15, 2016
diff --git a/RedirectLogin.java b/RedirectLogin.java
@@ -0,0 +1,231 @@
+package loginServices;
+
+import com.sap.security.core.logon.imp.SAPJ2EECallbackHandler;
+import com.sap.engine.interfaces.security.auth.LoginContextFactory;
+import java.io.IOException;
+import java.io.PrintWriter;
+import javax.security.auth.login.LoginContext;
+import javax.security.auth.login.LoginException;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import javax.servlet.RequestDispatcher;
+import java.util.Enumeration;
+import java.util.Map;
+import java.util.List;
+import javax.servlet.http.Cookie;
+
+import java.net.URL;
+import java.net.MalformedURLException;
+import java.net.HttpURLConnection;
+import java.net.HttpCookie;
+
+public class RedirectLogin extends HttpServlet
+{
+
+  private String authenticationStack;
+  private String authenticationRealm;
+
+  public void init()
+  {            
+    ServletContext servletContext = getServletContext();
+    this.authenticationStack = servletContext.getInitParameter("authenticationStack");
+    this.authenticationRealm = servletContext.getInitParameter("authenticationRealm");
+  }
+
+  protected void doGet(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException, IOException
+  {
+    doPost(request, response);
+  }
+
+  protected void doPost(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException, IOException
+  {
+
+// Sehr gern hätte ich es auf diese Weise gemacht - aber das ging nicht:
+//    RequestDispatcher rd = request.getRequestDispatcher("/nwa");
+//    rd.include(request,response);
+
+    try {
+
+        PrintWriter w = response.getWriter();
+
+        HttpServletRequest httpRequest = (HttpServletRequest) request;
+
+        Cookie mysapsso2;
+        mysapsso2 = getMYSAPSSO2( httpRequest );
+        if (mysapsso2==null) {
+          mysapsso2 = createMYSAPSSO2( httpRequest );
+        }        
+
+        if (mysapsso2 != null) {
+          String redirectURL = getRedirectURL(request);
+          response.addCookie( mysapsso2 );        
+          response.sendRedirect(redirectURL);
+          response.getWriter().println("OK");                        
+        }
+        else throw new LoginException("Could not retrieve MYSAPSSO2 ticket");
+
+      } catch (Throwable t) {
+
+        response.setContentType("text/plain");
+        response.setStatus(401);
+
+        PrintWriter w = response.getWriter();
+        w.println("Exception: " + t.getMessage() );
+        t.printStackTrace(w);
+
+      }
+
+  }
+
+
+
+  protected void doPost1(HttpServletRequest request, HttpServletResponse response)
+    throws ServletException, IOException
+  {
+    try
+    {
+
+      if (doLogin(request)) {
+        SAPJ2EECallbackHandler callbackHandler = new SAPJ2EECallbackHandler(request, response);
+        LoginContext lc = LoginContextFactory.getLoginContext("ticket", callbackHandler);
+        lc.login();
+      }  
+
+      String redirectURL = getRedirectURL(request);
+      response.sendRedirect(redirectURL);
+      response.getWriter().println("OK");
+
+    }
+    catch (LoginException le) {
+
+      if (this.authenticationRealm.matches("\\S")) {
+        response.setHeader("WWW-Authenticate", this.authenticationRealm);
+      }
+
+      response.setContentType("text/html");
+      response.setStatus(401);
+
+      PrintWriter w = response.getWriter();
+      w.println("<html><body><h2>Not authorized (RedirectLogin.java)</h2>");
+      if (traceMode(request)) {
+        w.println("Authentication stack: "+this.authenticationStack);
+        w.println("Authentication realm: "+this.authenticationRealm);
+        w.println("Exception cause: "+le.getMessage());
+        w.println("<pre>");
+        le.printStackTrace(w);      
+        w.println("</pre>");
+        Throwable t = le.getCause();
+        if (t!=null) {
+          w.println("Cause: "+t.getMessage()+"<pre>");
+          t.printStackTrace();
+          w.println("</pre>");
+          }
+        else {
+          w.println("(no causing exception given)");
+        }  
+      }  
+      w.println("</body></html>");
+    }
+  }
+
+  private Cookie getMYSAPSSO2(HttpServletRequest httpRequest) {
+    Cookie[] cookies = httpRequest.getCookies();
+    if (cookies != null && cookies.length > 0) {
+      for (Cookie c : cookies) {
+        if (c.getName().equals("MYSAPSSO2")) {
+          return c;         
+        }
+      }
+    }
+    return null; 
+  }
+
+  private Cookie createMYSAPSSO2( HttpServletRequest request ) throws LoginException, IOException, MalformedURLException {  
+
+    // Authentifizierung verlangt die Existenz des Headerfelds            
+    if ( request.getHeader("dxmSAPusername") == null ) {
+      throw new LoginException("No Airlock authentication");
+    }
+
+    // HTTP-Verbindung zu /nwa aufmachen, um MYSAPSSO2 Cookie zu erzeugen
+    URL nwa = new URL( request.getRequestURL().toString().replace("/RedirectLogin/redirect","/nwa") );
+    HttpURLConnection c = (HttpURLConnection)nwa.openConnection();
+    // Alle Headerfelder ausser cookie wie ein Proxy übernehmen      
+    Enumeration<String> headerNames = request.getHeaderNames();
+    if (headerNames != null) {
+       while (headerNames.hasMoreElements()) {
+         String headerFieldName = headerNames.nextElement();
+         if (headerFieldName.equals("cookie")) continue;
+         c.setRequestProperty(headerFieldName,request.getHeader(headerFieldName) );
+       }                        
+    }        
+
+    // (synchronen) Request auf /nwa ausführen...
+    c.connect();
+
+    // Hat geklappt
+    if (c.getResponseCode( ) == 200) {
+      // MYSAPSSO2 Cookie aus der Antwort herausschälen
+      Map<String, List<String>> responseHeaderFields = c.getHeaderFields();
+      List<String> cookiesHeader = responseHeaderFields.get("set-cookie");
+      if (cookiesHeader != null) {
+        for (String cs : cookiesHeader) {
+          HttpCookie ch = HttpCookie.parse( cs ).get(0);
+          if (ch.getName().equals("MYSAPSSO2")) {
+           return servletCookie(ch);
+          }
+        }
+        throw new LoginException("Authentication response contains not MYSAPSSO2 ticket");
+      } else throw new LoginException("Authentication response incomplete"+responseHeaderFields);  
+    } else throw new LoginException("HTTP error code " + c.getResponseCode() + " from authentication"); 
+
+  }
+
+  private Cookie servletCookie(HttpCookie c){
+    Cookie _c=new Cookie(c.getName(),c.getValue());
+    if (c.getComment() != null) {
+      _c.setComment(c.getComment());
+    }
+    if (c.getDomain() != null) {
+      _c.setDomain(c.getDomain());
+    }
+    if (c.getPath() != null) {
+      _c.setPath(c.getPath());
+    }
+    _c.setSecure(c.getSecure());
+    _c.setVersion(c.getVersion());
+    //_c.setHttpOnly(c.getDiscard());
+    _c.setMaxAge((int)c.getMaxAge());
+    return _c;
+  }  
+
+  private String getRedirectURL(HttpServletRequest request)
+  {
+    String dest = request.getHeader("migros-redirect");
+    if ((dest == null) || (dest.equals("")))
+    {
+      dest = request.getParameter("migros-redirect");
+      if ((dest == null) || (dest.equals("")))
+      {
+        dest = getServletContext().getInitParameter("defaultRedirectURL");
+      }
+    }
+    return dest;
+  }
+
+  private boolean traceMode(HttpServletRequest request) {
+      String trc = request.getParameter("trc");
+      return ((trc != null) && trc.equals("on"));
+  }
+
+  private boolean doLogin(HttpServletRequest request) {
+      String login = request.getParameter("login");
+      return ((login == null) || !login.equals("off"));
+  }
+
+}