Correct csrf-token impl.

[gigi.git] / src / org / cacert / gigi / output / Form.java

diff --git a/src/org/cacert/gigi/output/Form.java b/src/org/cacert/gigi/output/Form.java
index 9a27127c65e1c82b69f7ebb1e0103e76f3707b70..16440cc3213e8a64ec306c568f38d4d2a4342ab1 100644 (file)
--- a/src/org/cacert/gigi/output/Form.java
+++ b/src/org/cacert/gigi/output/Form.java
@@ -1,19 +1,69 @@
 package org.cacert.gigi.output;
 
 import java.io.PrintWriter;
+import java.util.Map;
 
 import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpSession;
 
+import org.cacert.gigi.Language;
 import org.cacert.gigi.pages.Page;
+import org.cacert.gigi.util.RandomToken;
 
 public abstract class Form implements Outputable {
+       String csrf;
+
+       public Form(HttpServletRequest hsr) {
+               csrf = RandomToken.generateToken(32);
+               HttpSession hs = hsr.getSession();
+               hs.setAttribute("form/" + getClass().getName() + "/" + csrf, this);
+
+       }
+
        public abstract boolean submit(PrintWriter out, HttpServletRequest req);
 
+       @Override
+       public final void output(PrintWriter out, Language l, Map<String, Object> vars) {
+               out.println("<form method='POST' autocomplete='off'>");
+               outputContent(out, l, vars);
+               out.print("<input type='hidden' name='csrf' value='");
+               out.print(getCSRFToken());
+               out.println("'></form>");
+       }
+
+       protected abstract void outputContent(PrintWriter out, Language l, Map<String, Object> vars);
+
        protected void outputError(PrintWriter out, ServletRequest req, String text) {
                out.print("<div>");
                out.print(Page.translate(req, text));
                out.println("</div>");
        }
 
+       protected String getCSRFToken() {
+               return csrf;
+       }
+
+       protected void checkCSRF(HttpServletRequest req) {
+               if (!csrf.equals(req.getParameter("csrf"))) {
+                       throw new CSRFError();
+               }
+       }
+
+       public static <T extends Form> T getForm(HttpServletRequest req, Class<T> target) {
+               String csrf = req.getParameter("csrf");
+               if (csrf == null) {
+                       throw new CSRFError();
+               }
+               HttpSession hs = req.getSession();
+               if (hs == null) {
+                       throw new CSRFError();
+               }
+               Form f = (Form) hs.getAttribute("form/" + target.getName() + "/" + csrf);
+               return (T) f;
+       }
+
+       public static class CSRFError extends Error {
+
+       }
 }