Bug 346139: self-hosted site launching not workingv20110516-1749-fixes-20110519-1147

- avoid infinite loops of proxy requests
https://bugs.eclipse.org/bugs/show_bug.cgi?id=346139

1 files changed, 18 insertions, 0 deletions

diff --git a/bundles/org.eclipse.orion.server.hosting/src/org/eclipse/orion/internal/server/hosting/RemoteURLProxyServlet.java b/bundles/org.eclipse.orion.server.hosting/src/org/eclipse/orion/internal/server/hosting/RemoteURLProxyServlet.java
index 343b44f..53b0c9b 100644
--- a/bundles/org.eclipse.orion.server.hosting/src/org/eclipse/orion/internal/server/hosting/RemoteURLProxyServlet.java
+++ b/bundles/org.eclipse.orion.server.hosting/src/org/eclipse/orion/internal/server/hosting/RemoteURLProxyServlet.java
@@ -124,6 +124,24 @@ public class RemoteURLProxyServlet extends ProxyServlet {
 			if (!xForwardedFor)

 				connection.addRequestProperty("X-Forwarded-For", request.getRemoteAddr());

 

+			// Bug 346139: prevent an infinite proxy loop by decrementing the Max-Forwards header

+			Enumeration maxForwardsHeaders = request.getHeaders("Max-Forwards");

+			String maxForwardsHeader = null;

+			while (maxForwardsHeaders.hasMoreElements()) {

+				maxForwardsHeader = (String) maxForwardsHeaders.nextElement();

+			}

+			int maxForwards = 5;

+			try {

+				maxForwards = Math.max(0, Integer.parseInt(maxForwardsHeader));

+			} catch (NumberFormatException e) {

+				// Use default

+			}

+			if (maxForwards-- < 1) {

+				response.sendError(HttpURLConnection.HTTP_BAD_GATEWAY, "Max-Forwards exceeded");

+				return;

+			}

+			connection.addRequestProperty("Max-Forwards", "" + maxForwards);

+

 			// a little bit of cache control

 			String cache_control = request.getHeader("Cache-Control");

 			if (cache_control != null && (cache_control.indexOf("no-cache") >= 0 || cache_control.indexOf("no-store") >= 0))