detecting infinite redirect loops (Feature #192)

stamparm · stamparm · commit d2f88b6ebead · 2010-07-19T12:38:30.000Z
diff --git a/lib/request/redirecthandler.py b/lib/request/redirecthandler.py
@@ -24,7 +24,17 @@
 
 import urllib2
 
+from lib.core.exception import sqlmapConnectionException
+
 class SmartRedirectHandler(urllib2.HTTPRedirectHandler):
+    # maximum number of redirections to any single URL
+    # this is needed because of the state that cookies introduce
+    max_repeats = 4
+
+    # maximum total number of redirections (regardless of URL) before
+    # assuming we're in a loop
+    max_redirections = 10
+
     def common_http_redirect(self, result, headers, code):
         if "location" in headers:
             result.redurl = headers.getheaders("location")[0].split("?")[0]
@@ -36,9 +46,17 @@ def common_http_redirect(self, result, headers, code):
         return result
 
     def http_error_301(self, req, fp, code, msg, headers):
+        self.infinite_loop_check(req)
         result = urllib2.HTTPRedirectHandler.http_error_301(self, req, fp, code, msg, headers)
         return self.common_http_redirect(result, headers, code)
 
     def http_error_302(self, req, fp, code, msg, headers):
+        self.infinite_loop_check(req)
         result = urllib2.HTTPRedirectHandler.http_error_302(self, req, fp, code, msg, headers)
         return self.common_http_redirect(result, headers, code)
+
+    def infinite_loop_check(self, req):
+        if hasattr(req, 'redirect_dict') and (req.redirect_dict.get(req.get_full_url(), 0) >= self.max_repeats or len(req.redirect_dict) >= self.max_redirections):
+            errMsg  = "infinite redirect loop detected (%s). " % ", ".join(item for item in req.redirect_dict.keys())
+            errMsg += "please check all provided parameters and/or provide missing ones."
+            raise sqlmapConnectionException, errMsg
