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commit 264c4a8eb49248723d9dd6cfa7b1be4eaa95c5e3
parent 5ee2aba9cce8bb1d90b251ad7d0dc95e74e74fe7
Author: Christian Grothoff <christian@grothoff.org>
Date:   Sat, 10 Oct 2026 21:27:32 +0200

cap long-polling at 30 minutes

Diffstat:
M
src/include/taler/taler_mhd_lib.h
 | 
6
++++--
M
src/mhd/mhd_parsing.c
 | 
17
+++++++++++++++--

2 files changed, 19 insertions(+), 4 deletions(-)
diff --git a/src/include/taler/taler_mhd_lib.h b/src/include/taler/taler_mhd_lib.h
@@ -534,7 +534,8 @@ TALER_MHD_parse_request_arg_rel_time (struct MHD_Connection *connection,
  *
  * @param connection the MHD connection
  * @param[out] expiration set to #GNUNET_TIME_UNIT_ZERO_ABS if there was no timeout,
- *         the current time plus the value given under "timeout_ms" otherwise
+ *         the current time plus the value given under "timeout_ms" otherwise,
+ *         where values above 30 minutes are treated as 30 minutes
  * @return #GNUNET_OK on success, #GNUNET_NO if an
  *     error was returned on @a connection (caller should return #MHD_YES) and
  *     #GNUNET_SYSERR if we failed to return an error (caller should return #MHD_NO)
@@ -551,7 +552,8 @@ TALER_MHD_parse_request_arg_timeout (struct MHD_Connection *connection,
  *
  * @param connection the MHD connection
  * @param[out] expiration set to #GNUNET_TIME_UNIT_ZERO_ABS if there was no timeout,
- *         the current time plus the value given under "timeout_ms" otherwise
+ *         the current time plus the value given under "timeout_ms" otherwise,
+ *         where values above 30 minutes are treated as 30 minutes
  */
 #define TALER_MHD_parse_request_timeout(connection,expiration) \
         do {                                                         \
diff --git a/src/mhd/mhd_parsing.c b/src/mhd/mhd_parsing.c
@@ -27,6 +27,16 @@
 #include "taler/taler_mhd_lib.h"
 
 
+/**
+ * Longest long-poll wait we grant a client, in milliseconds.  While
+ * long-polling, the connection is suspended and thus not subject to
+ * MHD's connection timeout, so without a bound a client could pin the
+ * connection (with its file descriptor and database event handler)
+ * for the lifetime of the process.  Clients simply poll again.
+ */
+#define MAX_TIMEOUT_MS (30LLU * 60 * 1000)
+
+
 enum GNUNET_GenericReturnValue
 TALER_MHD_parse_post_json (struct MHD_Connection *connection,
                            void **con_cls,
@@ -210,8 +220,9 @@ TALER_MHD_parse_request_arg_rel_time (
       ? GNUNET_NO
       : GNUNET_SYSERR;
   }
-  *duration = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS,
-                                             tms);
+  *duration = GNUNET_TIME_relative_saturating_multiply (
+    GNUNET_TIME_UNIT_MILLISECONDS,
+    tms);
   return GNUNET_OK;
 }
 
@@ -250,6 +261,8 @@ TALER_MHD_parse_request_arg_timeout (
       ? GNUNET_NO
       : GNUNET_SYSERR;
   }
+  if (tms > MAX_TIMEOUT_MS)
+    tms = MAX_TIMEOUT_MS;
   *expiration = GNUNET_TIME_relative_to_absolute (
     GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS,
                                    tms));