changing UUID types (in preparation for RTT tracking)

1 files changed, 116 insertions, 21 deletions

diff --git a/src/transport/gnunet-service-tng.c b/src/transport/gnunet-service-tng.c
index c4974ca23..a35357d9b 100644
--- a/src/transport/gnunet-service-tng.c
+++ b/src/transport/gnunet-service-tng.c
@@ -25,6 +25,21 @@
  * TODO:
  * Implement next:
  * - track RTT, distance, loss, etc. => requires extra data structures!
+ *   => fragment UUIDs should be 'sequential' 32-bit numbers, for cummulative
+ * acks with Bitmask
+ *      => fragments carry their own offsets, so receiver will NOT require
+ *         seeing all the possible values
+ *      => can generate 'fresh' UUIDs for each retransmission to track it
+ *         => but need to keep 'map' of 32-bit UUID to queue!
+ *   => message UUIDs are currently overkill with 256 bits
+ *      => cummulative acks for messages include full UUID list
+ *      => message UUID size should be chosen to result in 8 byte alignment
+ *      => could encode 32-bit counter + 32-bit queue UUID in 64-bit message
+ * UUID?
+ *         => Use multihashmap32 on counter for lookup in hashmap?
+ *      => FIXME: 2x32 bit introduced, but still set to random value
+ *         instead of using the generators!
+ *         (and generators not initialized to random starting values either)
  * - consider replacing random `struct GNUNET_ShortHashCode` message UUIDs
  *   with (incrementing) 64-bit numbers (compacting both
  *   `struct TransportReliabilityBox` and `struct
@@ -260,9 +275,16 @@ GNUNET_NETWORK_STRUCT_BEGIN
 struct MessageUUIDP
 {
   /**
-   * Unique value.
+   * Unique value, generated by incrementing the
+   * `message_uuid_ctr` of `struct Neighbour`.
    */
-  struct GNUNET_ShortHashCode uuid; // FIXME: change to 8 bytes
+  uint32_t uuid GNUNET_PACKED;
+
+  /**
+   * UUID of the queue that was used to transmit this message.
+   * Used to map acknowledgements back to the respective queue.
+   */
+  uint32_t queue_uuid GNUNET_PACKED;
 };
 
 
@@ -274,7 +296,7 @@ struct FragmentUUIDP
   /**
    * Unique value identifying a fragment, in NBO.
    */
-  uint32_t uuid GNUNET_PACKED; // FIXME: change to 2x 2 bytes?
+  uint32_t uuid GNUNET_PACKED;
 };
 
 
@@ -1278,6 +1300,14 @@ struct Queue
   uint32_t qid;
 
   /**
+   * UUID used to map acknowledgements back to the queue that
+   * was used for transmission. Note that @e queue_uuid-s are
+   * only unique per neighbour (generated via `queue_uuid_gen`
+   * of `struct Neighbour`).
+   */
+  uint32_t queue_uuid;
+
+  /**
    * Maximum transmission unit supported by this queue.
    */
   uint32_t mtu;
@@ -1426,7 +1456,7 @@ struct Neighbour
    * reassembly. May be NULL if we currently have no fragments from
    * this @e pid (lazy initialization).
    */
-  struct GNUNET_CONTAINER_MultiShortmap *reassembly_map;
+  struct GNUNET_CONTAINER_MultiHashMap32 *reassembly_map;
 
   /**
    * Heap with `struct ReassemblyContext` structs for fragments under
@@ -1497,6 +1527,26 @@ struct Neighbour
   struct GNUNET_TIME_Absolute earliest_timeout;
 
   /**
+   * Incremented by one for each queue to generate
+   * unique queue identifiers. Initially set to a random value.
+   *
+   * FIXME: Deal with wrap around (might be triggered by very
+   * persistent adversary).
+   */
+  uint32_t queue_uuid_gen;
+
+  /**
+   * Incremented by one for each message sent to this neighbour, to
+   * uniquely identify that message in replies (note that fragments
+   * use another additional counter). Initially set to a random value.
+   *
+   * It should be safe to assume that by the time this value may wrap
+   * around, the original message is long "gone" and no longer
+   * relevant.
+   */
+  uint32_t message_uuid_ctr;
+
+  /**
    * Do we have a confirmed working queue and are thus visible to
    * CORE?
    */
@@ -2421,9 +2471,9 @@ free_reassembly_context (struct ReassemblyContext *rc)
 
   GNUNET_assert (rc == GNUNET_CONTAINER_heap_remove_node (rc->hn));
   GNUNET_assert (GNUNET_OK ==
-                 GNUNET_CONTAINER_multishortmap_remove (n->reassembly_map,
-                                                        &rc->msg_uuid.uuid,
-                                                        rc));
+                 GNUNET_CONTAINER_multihashmap32_remove (n->reassembly_map,
+                                                         rc->msg_uuid.uuid,
+                                                         rc));
   GNUNET_free (rc);
 }
 
@@ -2467,9 +2517,7 @@ reassembly_cleanup_task (void *cls)
  * @return #GNUNET_OK (continue iteration)
  */
 static int
-free_reassembly_cb (void *cls,
-                    const struct GNUNET_ShortHashCode *key,
-                    void *value)
+free_reassembly_cb (void *cls, uint32_t key, void *value)
 {
   struct ReassemblyContext *rc = value;
 
@@ -2499,10 +2547,10 @@ free_neighbour (struct Neighbour *neighbour)
     GNUNET_SCHEDULER_cancel (neighbour->timeout_task);
   if (NULL != neighbour->reassembly_map)
   {
-    GNUNET_CONTAINER_multishortmap_iterate (neighbour->reassembly_map,
-                                            &free_reassembly_cb,
-                                            NULL);
-    GNUNET_CONTAINER_multishortmap_destroy (neighbour->reassembly_map);
+    GNUNET_CONTAINER_multihashmap32_iterate (neighbour->reassembly_map,
+                                             &free_reassembly_cb,
+                                             NULL);
+    GNUNET_CONTAINER_multihashmap32_destroy (neighbour->reassembly_map);
     neighbour->reassembly_map = NULL;
     GNUNET_CONTAINER_heap_destroy (neighbour->reassembly_heap);
     neighbour->reassembly_heap = NULL;
@@ -4242,6 +4290,48 @@ send_fragment_ack (struct ReassemblyContext *rc)
 
 
 /**
+ * Closure for #find_by_message_uuid.
+ */
+struct FindByMessageUuidContext
+{
+  /**
+   * UUID to look for.
+   */
+  struct MessageUUIDP message_uuid;
+
+  /**
+   * Set to the reassembly context if found.
+   */
+  struct ReassemblyContext *rc;
+};
+
+
+/**
+ * Iterator called to find a reassembly context by the message UUID in the
+ * multihashmap32.
+ *
+ * @param cls a `struct FindByMessageUuidContext`
+ * @param key a key (unused)
+ * @param value a `struct ReassemblyContext`
+ * @return #GNUNET_YES if not found, #GNUNET_NO if found
+ */
+static int
+find_by_message_uuid (void *cls, uint32_t key, void *value)
+{
+  struct FindByMessageUuidContext *fc = cls;
+  struct ReassemblyContext *rc = value;
+
+  (void) key;
+  if (0 == GNUNET_memcmp (&fc->message_uuid, &rc->msg_uuid))
+  {
+    fc->rc = rc;
+    return GNUNET_NO;
+  }
+  return GNUNET_YES;
+}
+
+
+/**
  * Communicator gave us a fragment.  Process the request.
  *
  * @param cls a `struct CommunicatorMessageContext` (must call
@@ -4262,6 +4352,7 @@ handle_fragment_box (void *cls, const struct TransportFragmentBoxMessage *fb)
   char *target;
   struct GNUNET_TIME_Relative cdelay;
   int ack_now;
+  struct FindByMessageUuidContext fc;
 
   n = GNUNET_CONTAINER_multipeermap_get (neighbours, &cmc->im.sender);
   if (NULL == n)
@@ -4275,7 +4366,7 @@ handle_fragment_box (void *cls, const struct TransportFragmentBoxMessage *fb)
   }
   if (NULL == n->reassembly_map)
   {
-    n->reassembly_map = GNUNET_CONTAINER_multishortmap_create (8, GNUNET_YES);
+    n->reassembly_map = GNUNET_CONTAINER_multihashmap32_create (8);
     n->reassembly_heap =
       GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
     n->reassembly_timeout_task =
@@ -4284,9 +4375,13 @@ handle_fragment_box (void *cls, const struct TransportFragmentBoxMessage *fb)
                                     n);
   }
   msize = ntohs (fb->msg_size);
-  rc =
-    GNUNET_CONTAINER_multishortmap_get (n->reassembly_map, &fb->msg_uuid.uuid);
-  if (NULL == rc)
+  fc.message_uuid = fb->msg_uuid;
+  fc.rc = NULL;
+  GNUNET_CONTAINER_multihashmap32_get_multiple (n->reassembly_map,
+                                                fb->msg_uuid.uuid,
+                                                &find_by_message_uuid,
+                                                &fc);
+  if (NULL == (rc = fc.rc))
   {
     rc = GNUNET_malloc (sizeof (*rc) + msize + /* reassembly payload buffer */
                         (msize + 7) / 8 * sizeof (uint8_t) /* bitfield */);
@@ -4300,11 +4395,11 @@ handle_fragment_box (void *cls, const struct TransportFragmentBoxMessage *fb)
                                            rc,
                                            rc->reassembly_timeout.abs_value_us);
     GNUNET_assert (GNUNET_OK ==
-                   GNUNET_CONTAINER_multishortmap_put (
+                   GNUNET_CONTAINER_multihashmap32_put (
                      n->reassembly_map,
-                     &rc->msg_uuid.uuid,
+                     rc->msg_uuid.uuid,
                      rc,
-                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
+                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
     target = (char *) &rc[1];
     rc->bitfield = (uint8_t *) (target + rc->msg_size);
     rc->msg_missing = rc->msg_size;