major clean up and bugfixes of SET

1 files changed, 304 insertions, 238 deletions

diff --git a/src/set/gnunet-service-set_intersection.c b/src/set/gnunet-service-set_intersection.c
index 8307672b9..9dc421792 100644
--- a/src/set/gnunet-service-set_intersection.c
+++ b/src/set/gnunet-service-set_intersection.c
@@ -56,6 +56,18 @@ enum IntersectionOperationPhase
   PHASE_BF_EXCHANGE,
 
   /**
+   * We must next send the P2P DONE message (after finishing mostly
+   * with the local client).  Then we will wait for the channel to close.
+   */
+  PHASE_MUST_SEND_DONE,
+
+  /**
+   * We have received the P2P DONE message, and must finish with the
+   * local client before terminating the channel.
+   */
+  PHASE_DONE_RECEIVED,
+
+  /**
    * The protocol is over.  Results may still have to be sent to the
    * client.
    */
@@ -162,6 +174,13 @@ struct OperationState
    * Did we send the client that we are done?
    */
   int client_done_sent;
+
+  /**
+   * Set whenever we reach the state where the death of the
+   * channel is perfectly find and should NOT result in the
+   * operation being cancelled.
+   */
+  int channel_death_expected;
 };
 
 
@@ -193,12 +212,12 @@ send_client_removed_element (struct Operation *op,
   struct GNUNET_MQ_Envelope *ev;
   struct GNUNET_SET_ResultMessage *rm;
 
-  if (GNUNET_SET_RESULT_REMOVED != op->spec->result_mode)
+  if (GNUNET_SET_RESULT_REMOVED != op->result_mode)
     return; /* Wrong mode for transmitting removed elements */
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Sending removed element (size %u) to client\n",
               element->size);
-  GNUNET_assert (0 != op->spec->client_request_id);
+  GNUNET_assert (0 != op->client_request_id);
   ev = GNUNET_MQ_msg_extra (rm,
                             element->size,
                             GNUNET_MESSAGE_TYPE_SET_RESULT);
@@ -208,12 +227,12 @@ send_client_removed_element (struct Operation *op,
     return;
   }
   rm->result_status = htons (GNUNET_SET_STATUS_OK);
-  rm->request_id = htonl (op->spec->client_request_id);
+  rm->request_id = htonl (op->client_request_id);
   rm->element_type = element->element_type;
   GNUNET_memcpy (&rm[1],
-          element->data,
-          element->size);
-  GNUNET_MQ_send (op->spec->set->client_mq,
+                 element->data,
+                 element->size);
+  GNUNET_MQ_send (op->set->cs->mq,
                   ev);
 }
 
@@ -397,9 +416,9 @@ fail_intersection_operation (struct Operation *op)
   ev = GNUNET_MQ_msg (msg,
                       GNUNET_MESSAGE_TYPE_SET_RESULT);
   msg->result_status = htons (GNUNET_SET_STATUS_FAILURE);
-  msg->request_id = htonl (op->spec->client_request_id);
+  msg->request_id = htonl (op->client_request_id);
   msg->element_type = htons (0);
-  GNUNET_MQ_send (op->spec->set->client_mq,
+  GNUNET_MQ_send (op->set->cs->mq,
                   ev);
   _GSS_operation_destroy (op,
                           GNUNET_YES);
@@ -428,8 +447,8 @@ send_bloomfilter (struct Operation *op)
      should use more bits to maximize its set reduction
      potential and minimize overall bandwidth consumption. */
   bf_elementbits = 2 + ceil (log2((double)
-                             (op->spec->remote_element_count /
-                                   (double) op->state->my_element_count)));
+                             (op->remote_element_count /
+                              (double) op->state->my_element_count)));
   if (bf_elementbits < 1)
     bf_elementbits = 1; /* make sure k is not 0 */
   /* optimize BF-size to ~50% of bits set */
@@ -515,12 +534,14 @@ send_client_done_and_destroy (void *cls)
   struct GNUNET_MQ_Envelope *ev;
   struct GNUNET_SET_ResultMessage *rm;
 
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Intersection succeeded, sending DONE to local client\n");
   ev = GNUNET_MQ_msg (rm,
                       GNUNET_MESSAGE_TYPE_SET_RESULT);
-  rm->request_id = htonl (op->spec->client_request_id);
+  rm->request_id = htonl (op->client_request_id);
   rm->result_status = htons (GNUNET_SET_STATUS_DONE);
   rm->element_type = htons (0);
-  GNUNET_MQ_send (op->spec->set->client_mq,
+  GNUNET_MQ_send (op->set->cs->mq,
                   ev);
   _GSS_operation_destroy (op,
                           GNUNET_YES);
@@ -528,6 +549,53 @@ send_client_done_and_destroy (void *cls)
 
 
 /**
+ * Remember that we are done dealing with the local client
+ * AND have sent the other peer our message that we are done,
+ * so we are not just waiting for the channel to die before
+ * telling the local client that we are done as our last act.
+ *
+ * @param cls the `struct Operation`.
+ */
+static void
+finished_local_operations (void *cls)
+{
+  struct Operation *op = cls;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "DONE sent to other peer, now waiting for other end to close the channel\n");
+  op->state->phase = PHASE_FINISHED;
+  op->state->channel_death_expected = GNUNET_YES;
+}
+
+
+/**
+ * Notify the other peer that we are done.  Once this message
+ * is out, we still need to notify the local client that we
+ * are done.
+ *
+ * @param op operation to notify for.
+ */
+static void
+send_p2p_done (struct Operation *op)
+{
+  struct GNUNET_MQ_Envelope *ev;
+  struct IntersectionDoneMessage *idm;
+
+  GNUNET_assert (PHASE_MUST_SEND_DONE == op->state->phase);
+  GNUNET_assert (GNUNET_NO == op->state->channel_death_expected);
+  ev = GNUNET_MQ_msg (idm,
+                      GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_DONE);
+  idm->final_element_count = htonl (op->state->my_element_count);
+  idm->element_xor_hash = op->state->my_xor;
+  GNUNET_MQ_notify_sent (ev,
+                         &finished_local_operations,
+                         op);
+  GNUNET_MQ_send (op->mq,
+                  ev);
+}
+
+
+/**
  * Send all elements in the full result iterator.
  *
  * @param cls the `struct Operation *`
@@ -550,10 +618,21 @@ send_remaining_elements (void *cls)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                 "Sending done and destroy because iterator ran out\n");
-    op->keep--;
     GNUNET_CONTAINER_multihashmap_iterator_destroy (op->state->full_result_iter);
     op->state->full_result_iter = NULL;
-    send_client_done_and_destroy (op);
+    if (PHASE_DONE_RECEIVED == op->state->phase)
+    {
+      op->state->phase = PHASE_FINISHED;
+      send_client_done_and_destroy (op);
+    }
+    else if (PHASE_MUST_SEND_DONE == op->state->phase)
+    {
+      send_p2p_done (op);
+    }
+    else
+    {
+      GNUNET_assert (0);
+    }
     return;
   }
   ee = nxt;
@@ -562,48 +641,136 @@ send_remaining_elements (void *cls)
               "Sending element %s:%u to client (full set)\n",
               GNUNET_h2s (&ee->element_hash),
               element->size);
-  GNUNET_assert (0 != op->spec->client_request_id);
+  GNUNET_assert (0 != op->client_request_id);
   ev = GNUNET_MQ_msg_extra (rm,
                             element->size,
                             GNUNET_MESSAGE_TYPE_SET_RESULT);
   GNUNET_assert (NULL != ev);
   rm->result_status = htons (GNUNET_SET_STATUS_OK);
-  rm->request_id = htonl (op->spec->client_request_id);
+  rm->request_id = htonl (op->client_request_id);
   rm->element_type = element->element_type;
   GNUNET_memcpy (&rm[1],
-          element->data,
-          element->size);
+                 element->data,
+                 element->size);
   GNUNET_MQ_notify_sent (ev,
                          &send_remaining_elements,
                          op);
-  GNUNET_MQ_send (op->spec->set->client_mq,
+  GNUNET_MQ_send (op->set->cs->mq,
                   ev);
 }
 
 
 /**
- * Inform the peer that this operation is complete.
+ * Fills the "my_elements" hashmap with the initial set of
+ * (non-deleted) elements from the set of the specification.
  *
- * @param op the intersection operation to fail
+ * @param cls closure with the `struct Operation *`
+ * @param key current key code for the element
+ * @param value value in the hash map with the `struct ElementEntry *`
+ * @return #GNUNET_YES (we should continue to iterate)
+ */
+static int
+initialize_map_unfiltered (void *cls,
+                           const struct GNUNET_HashCode *key,
+                           void *value)
+{
+  struct ElementEntry *ee = value;
+  struct Operation *op = cls;
+
+  if (GNUNET_NO == _GSS_is_element_of_operation (ee, op))
+    return GNUNET_YES; /* element not live in operation's generation */
+  GNUNET_CRYPTO_hash_xor (&op->state->my_xor,
+                          &ee->element_hash,
+                          &op->state->my_xor);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Initial full initialization of my_elements, adding %s:%u\n",
+              GNUNET_h2s (&ee->element_hash),
+              ee->element.size);
+  GNUNET_break (GNUNET_YES ==
+                GNUNET_CONTAINER_multihashmap_put (op->state->my_elements,
+                                                   &ee->element_hash,
+                                                   ee,
+                                                   GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
+  return GNUNET_YES;
+}
+
+
+/**
+ * Send our element count to the peer, in case our element count is
+ * lower than his.
+ *
+ * @param op intersection operation
  */
 static void
-send_peer_done (struct Operation *op)
+send_element_count (struct Operation *op)
 {
   struct GNUNET_MQ_Envelope *ev;
-  struct IntersectionDoneMessage *idm;
+  struct IntersectionElementInfoMessage *msg;
 
-  op->state->phase = PHASE_FINISHED;
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Intersection succeeded, sending DONE\n");
-  GNUNET_CONTAINER_bloomfilter_free (op->state->local_bf);
-  op->state->local_bf = NULL;
+              "Sending our element count (%u)\n",
+              op->state->my_element_count);
+  ev = GNUNET_MQ_msg (msg,
+                      GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_ELEMENT_INFO);
+  msg->sender_element_count = htonl (op->state->my_element_count);
+  GNUNET_MQ_send (op->mq, ev);
+}
 
-  ev = GNUNET_MQ_msg (idm,
-                      GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_DONE);
-  idm->final_element_count = htonl (op->state->my_element_count);
-  idm->element_xor_hash = op->state->my_xor;
-  GNUNET_MQ_send (op->mq,
-                  ev);
+
+/**
+ * We go first, initialize our map with all elements and
+ * send the first Bloom filter.
+ *
+ * @param op operation to start exchange for
+ */
+static void
+begin_bf_exchange (struct Operation *op)
+{
+  op->state->phase = PHASE_BF_EXCHANGE;
+  GNUNET_CONTAINER_multihashmap_iterate (op->set->content->elements,
+                                         &initialize_map_unfiltered,
+                                         op);
+  send_bloomfilter (op);
+}
+
+
+/**
+ * Handle the initial `struct IntersectionElementInfoMessage` from a
+ * remote peer.
+ *
+ * @param cls the intersection operation
+ * @param mh the header of the message
+ */
+void
+handle_intersection_p2p_element_info (void *cls,
+                                      const struct IntersectionElementInfoMessage *msg)
+{
+  struct Operation *op = cls;
+
+  if (GNUNET_SET_OPERATION_INTERSECTION != op->set->operation)
+  {
+    GNUNET_break_op (0);
+    fail_intersection_operation(op);
+    return;
+  }
+  op->remote_element_count = ntohl (msg->sender_element_count);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received remote element count (%u), I have %u\n",
+              op->remote_element_count,
+              op->state->my_element_count);
+  if ( ( (PHASE_INITIAL != op->state->phase) &&
+         (PHASE_COUNT_SENT != op->state->phase) ) ||
+       (op->state->my_element_count > op->remote_element_count) ||
+       (0 == op->state->my_element_count) ||
+       (0 == op->remote_element_count) )
+  {
+    GNUNET_break_op (0);
+    fail_intersection_operation(op);
+    return;
+  }
+  GNUNET_break (NULL == op->state->remote_bf);
+  begin_bf_exchange (op);
+  GNUNET_CADET_receive_done (op->channel);
 }
 
 
@@ -618,9 +785,9 @@ process_bf (struct Operation *op)
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Received BF in phase %u, foreign count is %u, my element count is %u/%u\n",
               op->state->phase,
-              op->spec->remote_element_count,
+              op->remote_element_count,
               op->state->my_element_count,
-              GNUNET_CONTAINER_multihashmap_size (op->spec->set->content->elements));
+              GNUNET_CONTAINER_multihashmap_size (op->set->content->elements));
   switch (op->state->phase)
   {
   case PHASE_INITIAL:
@@ -631,7 +798,7 @@ process_bf (struct Operation *op)
     /* This is the first BF being sent, build our initial map with
        filtering in place */
     op->state->my_element_count = 0;
-    GNUNET_CONTAINER_multihashmap_iterate (op->spec->set->content->elements,
+    GNUNET_CONTAINER_multihashmap_iterate (op->set->content->elements,
                                            &filtered_map_initialization,
                                            op);
     break;
@@ -641,6 +808,14 @@ process_bf (struct Operation *op)
                                            &iterator_bf_reduce,
                                            op);
     break;
+  case PHASE_MUST_SEND_DONE:
+    GNUNET_break_op (0);
+    fail_intersection_operation(op);
+    return;
+  case PHASE_DONE_RECEIVED:
+    GNUNET_break_op (0);
+    fail_intersection_operation(op);
+    return;
   case PHASE_FINISHED:
     GNUNET_break_op (0);
     fail_intersection_operation(op);
@@ -650,13 +825,28 @@ process_bf (struct Operation *op)
   op->state->remote_bf = NULL;
 
   if ( (0 == op->state->my_element_count) || /* fully disjoint */
-       ( (op->state->my_element_count == op->spec->remote_element_count) &&
+       ( (op->state->my_element_count == op->remote_element_count) &&
          (0 == memcmp (&op->state->my_xor,
                        &op->state->other_xor,
                        sizeof (struct GNUNET_HashCode))) ) )
   {
     /* we are done */
-    send_peer_done (op);
+    op->state->phase = PHASE_MUST_SEND_DONE;
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Intersection succeeded, sending DONE to other peer\n");
+    GNUNET_CONTAINER_bloomfilter_free (op->state->local_bf);
+    op->state->local_bf = NULL;
+    if (GNUNET_SET_RESULT_FULL == op->result_mode)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                  "Sending full result set (%u elements)\n",
+                  GNUNET_CONTAINER_multihashmap_size (op->state->my_elements));
+      op->state->full_result_iter
+        = GNUNET_CONTAINER_multihashmap_iterator_create (op->state->my_elements);
+      send_remaining_elements (op);
+      return;
+    }
+    send_p2p_done (op);
     return;
   }
   op->state->phase = PHASE_BF_EXCHANGE;
@@ -677,7 +867,7 @@ check_intersection_p2p_bf (void *cls,
 {
   struct Operation *op = cls;
 
-  if (GNUNET_SET_OPERATION_INTERSECTION != op->operation)
+  if (GNUNET_SET_OPERATION_INTERSECTION != op->set->operation)
   {
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
@@ -727,7 +917,7 @@ handle_intersection_p2p_bf (void *cls,
                                              bf_size,
                                              bf_bits_per_element);
       op->state->salt = ntohl (msg->sender_mutator);
-      op->spec->remote_element_count = ntohl (msg->sender_element_count);
+      op->remote_element_count = ntohl (msg->sender_element_count);
       process_bf (op);
       break;
     }
@@ -740,7 +930,7 @@ handle_intersection_p2p_bf (void *cls,
       op->state->bf_bits_per_element = bf_bits_per_element;
       op->state->bf_data_offset = 0;
       op->state->salt = ntohl (msg->sender_mutator);
-      op->spec->remote_element_count = ntohl (msg->sender_element_count);
+      op->remote_element_count = ntohl (msg->sender_element_count);
     }
     else
     {
@@ -749,7 +939,7 @@ handle_intersection_p2p_bf (void *cls,
            (op->state->bf_bits_per_element != bf_bits_per_element) ||
            (op->state->bf_data_offset + chunk_size > bf_size) ||
            (op->state->salt != ntohl (msg->sender_mutator)) ||
-           (op->spec->remote_element_count != ntohl (msg->sender_element_count)) )
+           (op->remote_element_count != ntohl (msg->sender_element_count)) )
       {
         GNUNET_break_op (0);
         fail_intersection_operation (op);
@@ -783,147 +973,6 @@ handle_intersection_p2p_bf (void *cls,
 
 
 /**
- * Fills the "my_elements" hashmap with the initial set of
- * (non-deleted) elements from the set of the specification.
- *
- * @param cls closure with the `struct Operation *`
- * @param key current key code for the element
- * @param value value in the hash map with the `struct ElementEntry *`
- * @return #GNUNET_YES (we should continue to iterate)
- */
-static int
-initialize_map_unfiltered (void *cls,
-                           const struct GNUNET_HashCode *key,
-                           void *value)
-{
-  struct ElementEntry *ee = value;
-  struct Operation *op = cls;
-
-  if (GNUNET_NO == _GSS_is_element_of_operation (ee, op))
-    return GNUNET_YES; /* element not live in operation's generation */
-  GNUNET_CRYPTO_hash_xor (&op->state->my_xor,
-                          &ee->element_hash,
-                          &op->state->my_xor);
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Initial full initialization of my_elements, adding %s:%u\n",
-              GNUNET_h2s (&ee->element_hash),
-              ee->element.size);
-  GNUNET_break (GNUNET_YES ==
-                GNUNET_CONTAINER_multihashmap_put (op->state->my_elements,
-                                                   &ee->element_hash,
-                                                   ee,
-                                                   GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
-  return GNUNET_YES;
-}
-
-
-/**
- * Send our element count to the peer, in case our element count is
- * lower than his.
- *
- * @param op intersection operation
- */
-static void
-send_element_count (struct Operation *op)
-{
-  struct GNUNET_MQ_Envelope *ev;
-  struct IntersectionElementInfoMessage *msg;
-
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Sending our element count (%u)\n",
-              op->state->my_element_count);
-  ev = GNUNET_MQ_msg (msg,
-                      GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_ELEMENT_INFO);
-  msg->sender_element_count = htonl (op->state->my_element_count);
-  GNUNET_MQ_send (op->mq, ev);
-}
-
-
-/**
- * We go first, initialize our map with all elements and
- * send the first Bloom filter.
- *
- * @param op operation to start exchange for
- */
-static void
-begin_bf_exchange (struct Operation *op)
-{
-  op->state->phase = PHASE_BF_EXCHANGE;
-  GNUNET_CONTAINER_multihashmap_iterate (op->spec->set->content->elements,
-                                         &initialize_map_unfiltered,
-                                         op);
-  send_bloomfilter (op);
-}
-
-
-/**
- * Handle the initial `struct IntersectionElementInfoMessage` from a
- * remote peer.
- *
- * @param cls the intersection operation
- * @param mh the header of the message
- */
-void
-handle_intersection_p2p_element_info (void *cls,
-                                      const struct IntersectionElementInfoMessage *msg)
-{
-  struct Operation *op = cls;
-
-  if (GNUNET_SET_OPERATION_INTERSECTION != op->operation)
-  {
-    GNUNET_break_op (0);
-    fail_intersection_operation(op);
-    return;
-  }
-  op->spec->remote_element_count = ntohl (msg->sender_element_count);
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Received remote element count (%u), I have %u\n",
-              op->spec->remote_element_count,
-              op->state->my_element_count);
-  if ( ( (PHASE_INITIAL != op->state->phase) &&
-         (PHASE_COUNT_SENT != op->state->phase) ) ||
-       (op->state->my_element_count > op->spec->remote_element_count) ||
-       (0 == op->state->my_element_count) ||
-       (0 == op->spec->remote_element_count) )
-  {
-    GNUNET_break_op (0);
-    fail_intersection_operation(op);
-    return;
-  }
-  GNUNET_break (NULL == op->state->remote_bf);
-  begin_bf_exchange (op);
-  GNUNET_CADET_receive_done (op->channel);
-}
-
-
-/**
- * Send a result message to the client indicating that the operation
- * is over.  After the result done message has been sent to the
- * client, destroy the evaluate operation.
- *
- * @param op intersection operation
- */
-static void
-finish_and_destroy (struct Operation *op)
-{
-  GNUNET_assert (GNUNET_NO == op->state->client_done_sent);
-
-  if (GNUNET_SET_RESULT_FULL == op->spec->result_mode)
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                "Sending full result set (%u elements)\n",
-                GNUNET_CONTAINER_multihashmap_size (op->state->my_elements));
-    op->state->full_result_iter
-      = GNUNET_CONTAINER_multihashmap_iterator_create (op->state->my_elements);
-    op->keep++;
-    send_remaining_elements (op);
-    return;
-  }
-  send_client_done_and_destroy (op);
-}
-
-
-/**
  * Remove all elements from our hashmap.
  *
  * @param cls closure with the `struct Operation *`
@@ -970,10 +1019,10 @@ handle_intersection_p2p_done (void *cls,
 {
   struct Operation *op = cls;
 
-  if (GNUNET_SET_OPERATION_INTERSECTION != op->operation)
+  if (GNUNET_SET_OPERATION_INTERSECTION != op->set->operation)
   {
     GNUNET_break_op (0);
-    fail_intersection_operation(op);
+    fail_intersection_operation (op);
     return;
   }
   if (PHASE_BF_EXCHANGE != op->state->phase)
@@ -1005,9 +1054,22 @@ handle_intersection_p2p_done (void *cls,
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Got IntersectionDoneMessage, have %u elements in intersection\n",
               op->state->my_element_count);
-  op->state->phase = PHASE_FINISHED;
-  finish_and_destroy (op);
+  op->state->phase = PHASE_DONE_RECEIVED;
   GNUNET_CADET_receive_done (op->channel);
+
+  GNUNET_assert (GNUNET_NO == op->state->client_done_sent);
+  if (GNUNET_SET_RESULT_FULL == op->result_mode)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Sending full result set to client (%u elements)\n",
+                GNUNET_CONTAINER_multihashmap_size (op->state->my_elements));
+    op->state->full_result_iter
+      = GNUNET_CONTAINER_multihashmap_iterator_create (op->state->my_elements);
+    send_remaining_elements (op);
+    return;
+  }
+  op->state->phase = PHASE_FINISHED;
+  send_client_done_and_destroy (op);
 }
 
 
@@ -1018,24 +1080,16 @@ handle_intersection_p2p_done (void *cls,
  *        begin the evaluation
  * @param opaque_context message to be transmitted to the listener
  *        to convince him to accept, may be NULL
+ * @return operation-specific state to keep in @a op
  */
-static void
+static struct OperationState *
 intersection_evaluate (struct Operation *op,
                        const struct GNUNET_MessageHeader *opaque_context)
 {
+  struct OperationState *state;
   struct GNUNET_MQ_Envelope *ev;
   struct OperationRequestMessage *msg;
 
-  op->state = GNUNET_new (struct OperationState);
-  /* we started the operation, thus we have to send the operation request */
-  op->state->phase = PHASE_INITIAL;
-  op->state->my_element_count = op->spec->set->state->current_set_element_count;
-  op->state->my_elements
-    = GNUNET_CONTAINER_multihashmap_create (op->state->my_element_count,
-                                            GNUNET_YES);
-
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Initiating intersection operation evaluation\n");
   ev = GNUNET_MQ_msg_nested_mh (msg,
                                 GNUNET_MESSAGE_TYPE_SET_P2P_OPERATION_REQUEST,
                                 opaque_context);
@@ -1043,20 +1097,30 @@ intersection_evaluate (struct Operation *op,
   {
     /* the context message is too large!? */
     GNUNET_break (0);
-    GNUNET_SERVICE_client_drop (op->spec->set->client);
-    return;
+    return NULL;
   }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Initiating intersection operation evaluation\n");
+  state = GNUNET_new (struct OperationState);
+  /* we started the operation, thus we have to send the operation request */
+  state->phase = PHASE_INITIAL;
+  state->my_element_count = op->set->state->current_set_element_count;
+  state->my_elements
+    = GNUNET_CONTAINER_multihashmap_create (state->my_element_count,
+                                            GNUNET_YES);
+
   msg->operation = htonl (GNUNET_SET_OPERATION_INTERSECTION);
-  msg->element_count = htonl (op->state->my_element_count);
+  msg->element_count = htonl (state->my_element_count);
   GNUNET_MQ_send (op->mq,
                   ev);
-  op->state->phase = PHASE_COUNT_SENT;
+  state->phase = PHASE_COUNT_SENT;
   if (NULL != opaque_context)
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                 "Sent op request with context message\n");
   else
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                 "Sent op request without context message\n");
+  return state;
 }
 
 
@@ -1066,53 +1130,33 @@ intersection_evaluate (struct Operation *op,
  *
  * @param op operation that will be accepted as an intersection operation
  */
-static void
+static struct OperationState *
 intersection_accept (struct Operation *op)
 {
+  struct OperationState *state;
+
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Accepting set intersection operation\n");
-  op->state = GNUNET_new (struct OperationState);
-  op->state->phase = PHASE_INITIAL;
-  op->state->my_element_count
-    = op->spec->set->state->current_set_element_count;
-  GNUNET_assert (NULL == op->state->my_elements);
-  op->state->my_elements
-    = GNUNET_CONTAINER_multihashmap_create (GNUNET_MIN (op->state->my_element_count,
-                                                        op->spec->remote_element_count),
+  state = GNUNET_new (struct OperationState);
+  state->phase = PHASE_INITIAL;
+  state->my_element_count
+    = op->set->state->current_set_element_count;
+  state->my_elements
+    = GNUNET_CONTAINER_multihashmap_create (GNUNET_MIN (state->my_element_count,
+                                                        op->remote_element_count),
                                             GNUNET_YES);
-  if (op->spec->remote_element_count < op->state->my_element_count)
+  op->state = state;
+  if (op->remote_element_count < state->my_element_count)
   {
     /* If the other peer (Alice) has fewer elements than us (Bob),
        we just send the count as Alice should send the first BF */
     send_element_count (op);
-    op->state->phase = PHASE_COUNT_SENT;
-    return;
+    state->phase = PHASE_COUNT_SENT;
+    return state;
   }
   /* We have fewer elements, so we start with the BF */
   begin_bf_exchange (op);
-}
-
-
-/**
- * Handler for peer-disconnects, notifies the client about the aborted
- * operation.  If we did not expect anything from the other peer, we
- * gracefully terminate the operation.
- *
- * @param op the destroyed operation
- */
-static void
-intersection_peer_disconnect (struct Operation *op)
-{
-  if (PHASE_FINISHED != op->state->phase)
-  {
-    fail_intersection_operation (op);
-    return;
-  }
-  /* the session has already been concluded */
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "Other peer disconnected (finished)\n");
-  if (GNUNET_NO == op->state->client_done_sent)
-    finish_and_destroy (op);
+  return state;
 }
 
 
@@ -1215,6 +1259,28 @@ intersection_remove (struct SetState *set_state,
 
 
 /**
+ * Callback for channel death for the intersection operation.
+ *
+ * @param op operation that lost the channel
+ */
+static void
+intersection_channel_death (struct Operation *op)
+{
+  if (GNUNET_YES == op->state->channel_death_expected)
+  {
+    /* oh goodie, we are done! */
+    send_client_done_and_destroy (op);
+  }
+  else
+  {
+    /* sorry, channel went down early, too bad. */
+    _GSS_operation_destroy (op,
+                            GNUNET_YES);
+  }
+}
+
+
+/**
  * Get the table with implementing functions for set intersection.
  *
  * @return the operation specific VTable
@@ -1229,8 +1295,8 @@ _GSS_intersection_vt ()
     .destroy_set = &intersection_set_destroy,
     .evaluate = &intersection_evaluate,
     .accept = &intersection_accept,
-    .peer_disconnect = &intersection_peer_disconnect,
     .cancel = &intersection_op_cancel,
+    .channel_death = &intersection_channel_death,
   };
 
   return &intersection_vt;