Add maximum message size

2 files changed, 22 insertions, 4 deletions

diff --git a/src/cadet/cadet_api.c b/src/cadet/cadet_api.c
index d5faf65ba..3c7829330 100644
--- a/src/cadet/cadet_api.c
+++ b/src/cadet/cadet_api.c
@@ -1352,6 +1352,7 @@ send_callback (void *cls, size_t size, void *buf)
       psize = th->notify (th->notify_cls,
                           size - sizeof (struct GNUNET_CADET_LocalData),
                           mh);
+
       if (psize > 0)
       {
         psize += sizeof (struct GNUNET_CADET_LocalData);
@@ -1379,6 +1380,8 @@ send_callback (void *cls, size_t size, void *buf)
       memcpy (cbuf, &th[1], th->size);
       psize = th->size;
     }
+    GNUNET_assert (GNUNET_CONSTANTS_MAX_CADET_MESSAGE_SIZE >= psize);
+
     if (th->timeout_task != GNUNET_SCHEDULER_NO_TASK)
       GNUNET_SCHEDULER_cancel (th->timeout_task);
     GNUNET_CONTAINER_DLL_remove (h->th_head, h->th_tail, th);
@@ -1709,14 +1712,15 @@ GNUNET_CADET_channel_get_info (struct GNUNET_CADET_Channel *channel,
 
 struct GNUNET_CADET_TransmitHandle *
 GNUNET_CADET_notify_transmit_ready (struct GNUNET_CADET_Channel *channel, int cork,
-                                   struct GNUNET_TIME_Relative maxdelay,
-                                   size_t notify_size,
-                                   GNUNET_CONNECTION_TransmitReadyNotify notify,
-                                   void *notify_cls)
+                                    struct GNUNET_TIME_Relative maxdelay,
+                                    size_t notify_size,
+                                    GNUNET_CONNECTION_TransmitReadyNotify notify,
+                                    void *notify_cls)
 {
   struct GNUNET_CADET_TransmitHandle *th;
 
   GNUNET_assert (NULL != channel);
+  GNUNET_assert (GNUNET_CONSTANTS_MAX_CADET_MESSAGE_SIZE >= notify_size);
   LOG (GNUNET_ERROR_TYPE_DEBUG, "CADET NOTIFY TRANSMIT READY\n");
   LOG (GNUNET_ERROR_TYPE_DEBUG, "    on channel %X\n", channel->chid);
   LOG (GNUNET_ERROR_TYPE_DEBUG, "    allow_send %d\n", channel->allow_send);
diff --git a/src/include/gnunet_constants.h b/src/include/gnunet_constants.h
index 705809186..1d2e65581 100644
--- a/src/include/gnunet_constants.h
+++ b/src/include/gnunet_constants.h
@@ -121,6 +121,20 @@ extern "C"
 #define GNUNET_CONSTANTS_MAX_ENCRYPTED_MESSAGE_SIZE (63 * 1024)
 
 /**
+ * Size of the CADET message overhead
+ * - sizeof(GNUNET_CADET_Encrypted) // FIXME use GNUNET_CADET_EncryptedAck when available
+ * - sizeof(GNUNET_CADET_Data)
+
+ */
+#define GNUNET_CONSTANTS_CADET_P2P_OVERHEAD (sizeof (struct GNUNET_CADET_Encrypted) + sizeof (struct GNUNET_CADET_Data))
+
+/**
+ * Same as core, the conservative value would be:
+ * GNUNET_CONSTANTS_MAX_ENCRYPTED_MESSAGE_SIZE - GNUNET_CONSTANTS_CADET_P2P_OVERHEAD
+ */
+#define GNUNET_CONSTANTS_MAX_CADET_MESSAGE_SIZE (62 * 1024)
+
+/**
  * Largest block that can be stored in the DHT.
  */
 #define GNUNET_CONSTANTS_MAX_BLOCK_SIZE (62 * 1024)