--- /dev/null
+/*
+ This file is part of GNUnet.
+ Copyright (C) 2009-2014 GNUnet e.V.
+
+ GNUnet is free software: you can redistribute it and/or modify it
+ under the terms of the GNU Affero General Public License as published
+ by the Free Software Foundation, either version 3 of the License,
+ or (at your option) any later version.
+
+ GNUnet is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file transport/communicator.h
+ * @brief common internal definitions for communicator services
+ * @author Christian Grothoff
+ */
+#ifndef COMMUNICATOR_H
+#define COMMUNICAOTR_H
+
+#include "gnunet_util_lib.h"
+#include "gnunet_protocols.h"
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/**
+ * Message used to tell a communicator about a successful
+ * key exchange.
+ *
+ * Note that this style of KX acknowledgement typically only applies
+ * for communicators where the underlying network protocol is
+ * unidirectional and/or lacks cryptography. Furthermore, this is
+ * just the recommended "generic" style, communicators are always free
+ * to implement original designs that better fit their requirements.
+ */
+struct GNUNET_TRANSPORT_CommunicatorGenericKXConfirmation
+{
+ /**
+ * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_COMMUNICATOR_KX_CONFIRMATION
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Timestamp from the original sender which identifies the original KX.
+ */
+ struct GNUNET_TIME_AbsoluteNBO monotonic_time;
+
+ /**
+ * How long does the receiver of the KX believe that the address
+ * on which the KX was received will continue to be valid.
+ */
+ struct GNUNET_TIME_RelativeNBO validity;
+
+ /**
+ * Hash of the shared secret. Specific hash function may depend on
+ * the communicator's protocol details.
+ */
+ struct GNUNET_HashCode token;
+};
+
+
+/**
+ * Message used to tell a communicator about the receiver's
+ * flow control limits and to acknowledge receipt of certain
+ * messages.
+ *
+ * Note that a sender MAY choose to violate the flow-control
+ * limits provided in this message by a receiver, which may
+ * result in messages being lost (after all, transport is an
+ * unreliable channel). So if the sender violates these
+ * constraints, it should expect that the receive will simply
+ * discard the (partially) received "old" messages.
+ *
+ * This way, if a sender or receiver crashes, there is no protocol
+ * violation.
+ *
+ * Note that this style of flow control typically only applies
+ * for communicators where the underlying network protocol does
+ * not already implement flow control. Furthermore, this is
+ * just the recommended "generic" style, communicators are always
+ * free to implement original designs that better fit their
+ * requirements.
+ */
+struct GNUNET_TRANSPORT_CommunicatorGenericFCLimits
+{
+ /**
+ * Type is #GNUNET_MESSAGE_TYPE_TRANSPORT_COMMUNICATOR_FC_LIMITS
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Maximum number of messages beyond the acknowledged message
+ * number that can still be transmitted concurrently without
+ * further acknowledgements.
+ */
+ uint32_t msg_window_size;
+
+ /**
+ * Up to which message number were all messages received.
+ */
+ uint64_t msg_cummulative_ack;
+
+ /**
+ * Maximum number of payload bytes beyond the acknowledged
+ * number of bytes can still be transmitted without further
+ * acknowledgements.
+ */
+ uint64_t bytes_window_size;
+
+ /**
+ * Cummulative acknowledgement for number of bytes received.
+ */
+ uint64_t bytes_cummulative_ack;
+
+ /**
+ * Followed by a variable-size bitfield for messages received
+ * beyond @e msg_cummulative_ack. Index at offset 0 must thus
+ * be zero, otherwise @e msg_cummulative_ack should be
+ * increased. Note that this field can be overall of 0 bytes.
+ * The variable-size bitfield must be a multiple of 64 bits
+ * long.
+ */
+ /* uint64_t msg_selective_ack_field[]; */
+};
+
+
+
+
+
+GNUNET_NETWORK_STRUCT_END
+
+/* end of communicator.h */
+#endif