1 files changed, 26 insertions, 15 deletions

diff --git a/src/backend/anastasis-httpd_truth.c b/src/backend/anastasis-httpd_truth.c
index 6c05ef8..54969bf 100644
--- a/src/backend/anastasis-httpd_truth.c
+++ b/src/backend/anastasis-httpd_truth.c
@@ -237,6 +237,27 @@ static struct GNUNET_SCHEDULER_Task *to_task;
 
 
 /**
+ * Generate a response telling the client that answering this
+ * challenge failed because the rate limit has been exceeded.
+ *
+ * @param gc request to answer for
+ * @return MHD status code
+ */
+static MHD_RESULT
+reply_rate_limited (const struct GetContext *gc)
+{
+  return TALER_MHD_REPLY_JSON_PACK (
+    gc->connection,
+    MHD_HTTP_TOO_MANY_REQUESTS,
+    TALER_MHD_PACK_EC (TALER_EC_ANASTASIS_TRUTH_RATE_LIMITED),
+    GNUNET_JSON_pack_uint64 ("request_limit",
+                             gc->authorization->retry_counter),
+    GNUNET_JSON_pack_time_rel ("request_frequency",
+                               gc->authorization->code_rotation_period));
+}
+
+
+/**
  * Timeout requests that are past their due date.
  *
  * @param cls NULL
@@ -991,9 +1012,8 @@ run_authorization_process (struct MHD_Connection *connection,
 
 
 /**
- * Use the database to rate-limit queries to the
- * authentication procedure, but without actually
- * storing 'real' challenge codes.
+ * Use the database to rate-limit queries to the authentication
+ * procedure, but without actually storing 'real' challenge codes.
  *
  * @param[in,out] gc context to rate limit requests for
  * @return #GNUNET_OK if rate-limiting passes,
@@ -1034,10 +1054,7 @@ rate_limit (struct GetContext *gc)
   if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
   {
     return (MHD_YES ==
-            TALER_MHD_reply_with_error (gc->connection,
-                                        MHD_HTTP_TOO_MANY_REQUESTS,
-                                        TALER_EC_ANASTASIS_TRUTH_RATE_LIMITED,
-                                        NULL))
+            reply_rate_limited (gc))
       ? GNUNET_NO
       : GNUNET_SYSERR;
   }
@@ -1066,10 +1083,7 @@ rate_limit (struct GetContext *gc)
       : GNUNET_SYSERR;
   case ANASTASIS_DB_CODE_STATUS_NO_RESULTS:
     return (MHD_YES ==
-            TALER_MHD_reply_with_error (gc->connection,
-                                        MHD_HTTP_TOO_MANY_REQUESTS,
-                                        TALER_EC_ANASTASIS_TRUTH_RATE_LIMITED,
-                                        NULL))
+            reply_rate_limited (gc))
       ? GNUNET_NO
       : GNUNET_SYSERR;
   case ANASTASIS_DB_CODE_STATUS_VALID_CODE_STORED:
@@ -1640,10 +1654,7 @@ AH_handler_truth_get (
       case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
         /* 0 == retry_counter of existing challenge => rate limit exceeded */
         GNUNET_free (decrypted_truth);
-        return TALER_MHD_reply_with_error (connection,
-                                           MHD_HTTP_TOO_MANY_REQUESTS,
-                                           TALER_EC_ANASTASIS_TRUTH_RATE_LIMITED,
-                                           NULL);
+        return reply_rate_limited (gc);
       case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT:
         /* challenge code was stored successfully*/
         GNUNET_log (GNUNET_ERROR_TYPE_INFO,