/* This file is part of GNUnet. (C) 2012 Christian Grothoff (and other contributing authors) GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, 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 General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * @file stream/stream_api.c * @brief Implementation of the stream library * @author Sree Harsha Totakura */ #include "platform.h" #include "gnunet_common.h" #include "gnunet_crypto_lib.h" #include "gnunet_stream_lib.h" #include "stream_protocol.h" /** * The maximum packet size of a stream packet */ #define MAX_PACKET_SIZE 64000 /** * The maximum payload a data message packet can carry */ static size_t max_payload_size = MAX_PACKET_SIZE - sizeof (struct GNUNET_STREAM_DataMessage); /** * Receive buffer */ #define RECEIVE_BUFFER_SIZE 4096000 /** * states in the Protocol */ enum State { /** * Client initialization state */ STATE_INIT, /** * Listener initialization state */ STATE_LISTEN, /** * Pre-connection establishment state */ STATE_HELLO_WAIT, /** * State where a connection has been established */ STATE_ESTABLISHED, /** * State where the socket is closed on our side and waiting to be ACK'ed */ STATE_RECEIVE_CLOSE_WAIT, /** * State where the socket is closed for reading */ STATE_RECEIVE_CLOSED, /** * State where the socket is closed on our side and waiting to be ACK'ed */ STATE_TRANSMIT_CLOSE_WAIT, /** * State where the socket is closed for writing */ STATE_TRANSMIT_CLOSED, /** * State where the socket is closed on our side and waiting to be ACK'ed */ STATE_CLOSE_WAIT, /** * State where the socket is closed */ STATE_CLOSED }; /** * Functions of this type are called when a message is written * * @param cls the closure from queue_message * @param socket the socket the written message was bound to */ typedef void (*SendFinishCallback) (void *cls, struct GNUNET_STREAM_Socket *socket); /** * The send message queue */ struct MessageQueue { /** * The message */ struct GNUNET_STREAM_MessageHeader *message; /** * Callback to be called when the message is sent */ SendFinishCallback finish_cb; /** * The closure for finish_cb */ void *finish_cb_cls; /** * The next message in queue. Should be NULL in the last message */ struct MessageQueue *next; /** * The next message in queue. Should be NULL in the last message */ struct MessageQueue *prev; }; /** * The STREAM Socket Handler */ struct GNUNET_STREAM_Socket { /** * The peer identity of the peer at the other end of the stream */ struct GNUNET_PeerIdentity other_peer; /** * Retransmission timeout */ struct GNUNET_TIME_Relative retransmit_timeout; /** * The Acknowledgement Bitmap */ GNUNET_STREAM_AckBitmap ack_bitmap; /** * Time when the Acknowledgement was queued */ struct GNUNET_TIME_Absolute ack_time_registered; /** * Queued Acknowledgement deadline */ struct GNUNET_TIME_Relative ack_time_deadline; /** * The task for sending timely Acks */ GNUNET_SCHEDULER_TaskIdentifier ack_task_id; /** * The mesh handle */ struct GNUNET_MESH_Handle *mesh; /** * The mesh tunnel handle */ struct GNUNET_MESH_Tunnel *tunnel; /** * Stream open closure */ void *open_cls; /** * Stream open callback */ GNUNET_STREAM_OpenCallback open_cb; /** * The current transmit handle (if a pending transmit request exists) */ struct GNUNET_MESH_TransmitHandle *transmit_handle; /** * The current message associated with the transmit handle */ struct MessageQueue *queue_head; /** * The queue tail, should always point to the last message in queue */ struct MessageQueue *queue_tail; /** * The write IO_handle associated with this socket */ struct GNUNET_STREAM_IOHandle *write_handle; /** * The read IO_handle associated with this socket */ struct GNUNET_STREAM_IOHandle *read_handle; /** * Buffer for storing received messages */ void *receive_buffer; /** * The state of the protocol associated with this socket */ enum State state; /** * The status of the socket */ enum GNUNET_STREAM_Status status; /** * The number of previous timeouts; FIXME: currently not used */ unsigned int retries; /** * The session id associated with this stream connection * FIXME: Not used currently, may be removed */ uint32_t session_id; /** * Write sequence number. Set to random when sending HELLO(client) and * HELLO_ACK(server) */ uint32_t write_sequence_number; /** * Read sequence number. This number's value is determined during handshake */ uint32_t read_sequence_number; /** * receiver's available buffer after the last acknowledged packet */ uint32_t receive_window_available; }; /** * A socket for listening */ struct GNUNET_STREAM_ListenSocket { /** * The mesh handle */ struct GNUNET_MESH_Handle *mesh; /** * The callback function which is called after successful opening socket */ GNUNET_STREAM_ListenCallback listen_cb; /** * The call back closure */ void *listen_cb_cls; /** * The service port */ GNUNET_MESH_ApplicationType port; }; /** * The IO Handle */ struct GNUNET_STREAM_IOHandle { /** * The packet_buffers associated with this Handle */ struct GNUNET_STREAM_DataMessage *messages[64]; /** * The bitmap of this IOHandle; Corresponding bit for a message is set when * it has been acknowledged by the receiver */ GNUNET_STREAM_AckBitmap ack_bitmap; /** * receiver's available buffer */ uint32_t receive_window_available; /** * Number of packets sent before waiting for an ack * * FIXME: Do we need this? */ unsigned int sent_packets; }; /** * Default value in seconds for various timeouts */ static unsigned int default_timeout = 300; /** * Callback function for sending hello message * * @param cls closure the socket * @param size number of bytes available in buf * @param buf where the callee should write the message * @return number of bytes written to buf */ static size_t send_message_notify (void *cls, size_t size, void *buf) { struct GNUNET_STREAM_Socket *socket = cls; struct MessageQueue *head; size_t ret; socket->transmit_handle = NULL; /* Remove the transmit handle */ head = socket->queue_head; if (NULL == head) return 0; /* just to be safe */ if (0 == size) /* request timed out */ { socket->retries++; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Message sending timed out. Retry %d \n", socket->retries); socket->transmit_handle = GNUNET_MESH_notify_transmit_ready (socket->tunnel, 0, /* Corking */ 1, /* Priority */ /* FIXME: exponential backoff */ socket->retransmit_timeout, &socket->other_peer, ntohs (head->message->header.size), &send_message_notify, socket); return 0; } ret = ntohs (head->message->header.size); GNUNET_assert (size >= ret); memcpy (buf, head->message, ret); if (NULL != head->finish_cb) { head->finish_cb (socket, head->finish_cb_cls); } GNUNET_CONTAINER_DLL_remove (socket->queue_head, socket->queue_tail, head); GNUNET_free (head->message); GNUNET_free (head); head = socket->queue_head; if (NULL != head) /* more pending messages to send */ { socket->retries = 0; socket->transmit_handle = GNUNET_MESH_notify_transmit_ready (socket->tunnel, 0, /* Corking */ 1, /* Priority */ /* FIXME: exponential backoff */ socket->retransmit_timeout, &socket->other_peer, ntohs (head->message->header.size), &send_message_notify, socket); } return ret; } /** * Queues a message for sending using the mesh connection of a socket * * @param socket the socket whose mesh connection is used * @param message the message to be sent * @param finish_cb the callback to be called when the message is sent * @param finish_cb_cls the closure for the callback */ static void queue_message (struct GNUNET_STREAM_Socket *socket, struct GNUNET_STREAM_MessageHeader *message, SendFinishCallback finish_cb, void *finish_cb_cls) { struct MessageQueue *queue_entity; queue_entity = GNUNET_malloc (sizeof (struct MessageQueue)); queue_entity->message = message; queue_entity->finish_cb = finish_cb; queue_entity->finish_cb_cls = finish_cb_cls; GNUNET_CONTAINER_DLL_insert_tail (socket->queue_head, socket->queue_tail, queue_entity); if (NULL == socket->transmit_handle) { socket->retries = 0; socket->transmit_handle = GNUNET_MESH_notify_transmit_ready (socket->tunnel, 0, /* Corking */ 1, /* Priority */ socket->retransmit_timeout, &socket->other_peer, ntohs (message->header.size), &send_message_notify, socket); } } /** * Callback function for sending ack message * * @param cls closure the ACK message created in ack_task * @param size number of bytes available in buffer * @param buf where the callee should write the message * @return number of bytes written to buf */ static size_t send_ack_notify (void *cls, size_t size, void *buf) { struct GNUNET_STREAM_AckMessage *ack_msg = cls; if (0 == size) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s called with size 0\n", __func__); return 0; } GNUNET_assert (ack_msg->header.header.size <= size); size = ack_msg->header.header.size; memcpy (buf, ack_msg, size); return size; } /** * Task for sending ACK message * * @param cls the socket * @param tc the Task context */ static void ack_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_STREAM_Socket *socket = cls; struct GNUNET_STREAM_AckMessage *ack_msg; if (GNUNET_SCHEDULER_REASON_SHUTDOWN == tc->reason) { return; } socket->ack_task_id = 0; /* Create the ACK Message */ ack_msg = GNUNET_malloc (sizeof (struct GNUNET_STREAM_AckMessage)); ack_msg->header.header.size = htons (sizeof (struct GNUNET_STREAM_AckMessage)); ack_msg->header.header.type = htons (GNUNET_MESSAGE_TYPE_STREAM_ACK); ack_msg->bitmap = GNUNET_htonll (socket->ack_bitmap); ack_msg->base_sequence_number = htonl (socket->read_sequence_number); ack_msg->receive_window_remaining = htonl (socket->receive_window_available); /* Request MESH for sending ACK */ GNUNET_MESH_notify_transmit_ready (socket->tunnel, 0, /* Corking */ 1, /* Priority */ socket->retransmit_timeout, &socket->other_peer, ntohs (ack_msg->header.header.size), &send_ack_notify, ack_msg); } /** * Function to modify a bit in GNUNET_STREAM_AckBitmap * * @param bitmap the bitmap to modify * @param bit the bit number to modify * @param value GNUNET_YES to on, GNUNET_NO to off */ static void ackbitmap_modify_bit (GNUNET_STREAM_AckBitmap *bitmap, unsigned int bit, int value) { GNUNET_assert (bit < 64); if (GNUNET_YES == value) *bitmap |= (1LL << bit); else *bitmap &= ~(1LL << bit); } /** * Function to check if a bit is set in the GNUNET_STREAM_AckBitmap * * @param bitmap address of the bitmap that has to be checked * @param bit the bit number to check * @return GNUNET_YES if the bit is set; GNUNET_NO if not */ static uint8_t ackbitmap_is_bit_set (const GNUNET_STREAM_AckBitmap *bitmap, unsigned int bit) { GNUNET_assert (bit < 64); return 0 != (*bitmap & (1LL << bit)); } /** * Function called when Data Message is sent * * @param cls the io_handle corresponding to the Data Message * @param socket the socket which was used */ static void write_data_finish_cb (void *cls, struct GNUNET_STREAM_Socket *socket) { struct GNUNET_STREAM_IOHandle *io_handle = cls; io_handle->sent_packets++; } /** * Writes data using the given socket. The amount of data written is limited by * the receive_window_size * * @param socket the socket to use */ static void write_data (struct GNUNET_STREAM_Socket *socket) { struct GNUNET_STREAM_IOHandle *io_handle = socket->write_handle; unsigned int packet; int ack_packet; ack_packet = -1; /* Find the last acknowledged packet */ for (packet=0; packet < 64; packet++) { if (GNUNET_YES == ackbitmap_is_bit_set (&io_handle->ack_bitmap, packet)) ack_packet = packet; else if (NULL == io_handle->messages[packet]) break; } /* Resend packets which weren't ack'ed */ for (packet=0; packet < ack_packet; packet++) { if (GNUNET_NO == ackbitmap_is_bit_set (&io_handle->ack_bitmap, packet)) { queue_message (socket, &io_handle->messages[packet]->header, NULL, NULL); } } packet = ack_packet + 1; /* Now send new packets if there is enough buffer space */ while ( (NULL != io_handle->messages[packet]) && (io_handle->receive_window_available >= ntohs (io_handle->messages[packet]->header.header.size)) ) { io_handle->receive_window_available -= ntohs (io_handle->messages[packet]->header.header.size); queue_message (socket, &io_handle->messages[packet]->header, &write_data_finish_cb, io_handle); packet++; } } /** * Handler for DATA messages; Same for both client and server * * @param socket the socket through which the ack was received * @param tunnel connection to the other end * @param sender who sent the message * @param msg the data message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int handle_data (struct GNUNET_STREAM_Socket *socket, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_STREAM_DataMessage *msg, const struct GNUNET_ATS_Information*atsi) { uint16_t size; const void *payload; size = msg->header.header.size; if (size < sizeof (struct GNUNET_STREAM_DataMessage)) { GNUNET_break_op (0); return GNUNET_SYSERR; } switch (socket->state) { case STATE_ESTABLISHED: case STATE_TRANSMIT_CLOSED: case STATE_TRANSMIT_CLOSE_WAIT: GNUNET_assert (NULL != socket->receive_buffer); /* check if the message's sequence number is greater than the one we are expecting */ if (ntohl (msg->sequence_number) - socket->read_sequence_number >= 64) {/* We are receiving a retransmitted message */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Message with sequence number %d retransmitted\n", ntohl (socket->read_sequence_number)); return GNUNET_YES; } /* Copy Data to buffer and send acknowledgement for this packet */ size -= sizeof (struct GNUNET_STREAM_DataMessage); payload = &msg[1]; memcpy (socket->receive_buffer + (ntohl (msg->sequence_number) - socket->read_sequence_number) * MAX_PACKET_SIZE, payload, size); /* Modify the ACK bitmap */ ackbitmap_modify_bit (&socket->ack_bitmap, ntohl (msg->sequence_number) - socket->read_sequence_number, GNUNET_YES); /* Start ACK sending task if one is not already present */ if (0 == socket->ack_task_id) { socket->ack_task_id = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_ntoh (msg->ack_deadline), &ack_task, socket); } break; default: /* FIXME: call statistics */ break; } return GNUNET_YES; } /** * Client's message Handler for GNUNET_MESSAGE_TYPE_STREAM_DATA * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx place to store local state associated with the tunnel * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_data (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return handle_data (socket, tunnel, sender, (const struct GNUNET_STREAM_DataMessage *) message, atsi); } /** * Callback to set state to ESTABLISHED * * @param cls the closure from queue_message FIXME: document * @param socket the socket to requiring state change */ static void set_state_established (void *cls, struct GNUNET_STREAM_Socket *socket) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Attaining ESTABLISHED state\n"); /* Initialize the receive buffer */ socket->receive_buffer = GNUNET_malloc (RECEIVE_BUFFER_SIZE); socket->state = STATE_ESTABLISHED; } /** * Callback to set state to HELLO_WAIT * * @param cls the closure from queue_message * @param socket the socket to requiring state change */ static void set_state_hello_wait (void *cls, struct GNUNET_STREAM_Socket *socket) { GNUNET_assert (STATE_INIT == socket->state); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Attaining HELLO_WAIT state\n"); socket->state = STATE_HELLO_WAIT; } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_HELLO_ACK * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_hello_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; const struct GNUNET_STREAM_HelloAckMessage *ack_msg; struct GNUNET_STREAM_HelloAckMessage *reply; ack_msg = (const struct GNUNET_STREAM_HelloAckMessage *) message; GNUNET_assert (socket->tunnel == tunnel); switch (socket->state) { case STATE_HELLO_WAIT: socket->read_sequence_number = ntohl (ack_msg->sequence_number); socket->receive_window_available = ntohl (ack_msg->receive_window_size); /* Get the random sequence number */ socket->write_sequence_number = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX); reply = GNUNET_malloc (sizeof (struct GNUNET_STREAM_HelloAckMessage)); reply->header.header.size = htons (sizeof (struct GNUNET_STREAM_MessageHeader)); reply->header.header.type = htons (GNUNET_MESSAGE_TYPE_STREAM_HELLO_ACK); reply->sequence_number = htonl (socket->write_sequence_number); reply->receive_window_size = htonl (RECEIVE_BUFFER_SIZE); queue_message (socket, &reply->header, &set_state_established, NULL); return GNUNET_OK; case STATE_ESTABLISHED: case STATE_RECEIVE_CLOSE_WAIT: // call statistics (# ACKs ignored++) return GNUNET_OK; case STATE_INIT: default: GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Server sent HELLO_ACK when in state %d\n", socket->state); socket->state = STATE_CLOSED; // introduce STATE_ERROR? return GNUNET_SYSERR; } } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_RESET * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_reset (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return GNUNET_OK; } /** * Common message handler for handling TRANSMIT_CLOSE messages * * @param socket the socket through which the ack was received * @param tunnel connection to the other end * @param sender who sent the message * @param msg the transmit close message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int handle_transmit_close (struct GNUNET_STREAM_Socket *socket, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_STREAM_MessageHeader *msg, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_MessageHeader *reply; switch (socket->state) { case STATE_ESTABLISHED: socket->state = STATE_RECEIVE_CLOSED; /* Send TRANSMIT_CLOSE_ACK */ reply = GNUNET_malloc (sizeof (struct GNUNET_STREAM_MessageHeader)); reply->header.type = htons (GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE_ACK); reply->header.size = htons (sizeof (struct GNUNET_STREAM_MessageHeader)); queue_message (socket, reply, NULL, NULL); break; default: /* FIXME: Call statistics? */ break; } return GNUNET_YES; } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_transmit_close (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return handle_transmit_close (socket, tunnel, sender, (struct GNUNET_STREAM_MessageHeader *)message, atsi); } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE_ACK * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_transmit_close_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return GNUNET_OK; } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_receive_close (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return GNUNET_OK; } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE_ACK * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_receive_close_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return GNUNET_OK; } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_CLOSE * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_close (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return GNUNET_OK; } /** * Client's message handler for GNUNET_MESSAGE_TYPE_STREAM_CLOSE_ACK * * @param cls the socket (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx this is NULL * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_close_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; return GNUNET_OK; } /*****************************/ /* Server's Message Handlers */ /*****************************/ /** * Server's message Handler for GNUNET_MESSAGE_TYPE_STREAM_DATA * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_data (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return handle_data (socket, tunnel, sender, (const struct GNUNET_STREAM_DataMessage *)message, atsi); } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_HELLO * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_hello (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; struct GNUNET_STREAM_HelloAckMessage *reply; GNUNET_assert (socket->tunnel == tunnel); if (STATE_INIT == socket->state) { /* Get the random sequence number */ socket->write_sequence_number = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX); reply = GNUNET_malloc (sizeof (struct GNUNET_STREAM_HelloAckMessage)); reply->header.header.size = htons (sizeof (struct GNUNET_STREAM_MessageHeader)); reply->header.header.type = htons (GNUNET_MESSAGE_TYPE_STREAM_HELLO_ACK); reply->sequence_number = htonl (socket->write_sequence_number); queue_message (socket, &reply->header, &set_state_hello_wait, NULL); } else { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Client sent HELLO when in state %d\n", socket->state); /* FIXME: Send RESET? */ } return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_HELLO_ACK * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_hello_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; const struct GNUNET_STREAM_HelloAckMessage *ack_message; ack_message = (struct GNUNET_STREAM_HelloAckMessage *) message; GNUNET_assert (socket->tunnel == tunnel); if (STATE_HELLO_WAIT == socket->state) { socket->read_sequence_number = ntohl (ack_message->sequence_number); socket->receive_window_available = ntohl (ack_message->receive_window_size); socket->state = STATE_ESTABLISHED; } else { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Client sent HELLO_ACK when in state %d\n", socket->state); /* FIXME: Send RESET? */ } return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_RESET * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_reset (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_transmit_close (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return handle_transmit_close (socket, tunnel, sender, (struct GNUNET_STREAM_MessageHeader *)message, atsi); } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE_ACK * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_transmit_close_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_receive_close (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE_ACK * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_receive_close_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_CLOSE * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_close (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return GNUNET_OK; } /** * Server's message handler for GNUNET_MESSAGE_TYPE_STREAM_CLOSE_ACK * * @param cls the closure * @param tunnel connection to the other end * @param tunnel_ctx the socket * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_close_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; return GNUNET_OK; } /** * Message Handler for mesh * * @param socket the socket through which the ack was received * @param tunnel connection to the other end * @param sender who sent the message * @param ack the acknowledgment message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int handle_ack (struct GNUNET_STREAM_Socket *socket, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_STREAM_AckMessage *ack, const struct GNUNET_ATS_Information*atsi) { switch (socket->state) { case (STATE_ESTABLISHED): if (NULL == socket->write_handle) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received DATA ACK when write_handle is NULL\n"); return GNUNET_OK; } socket->write_handle->ack_bitmap = GNUNET_ntohll (ack->bitmap); socket->write_handle->receive_window_available = ntohl (ack->receive_window_remaining); write_data (socket); break; default: break; } return GNUNET_OK; } /** * Message Handler for mesh * * @param cls the 'struct GNUNET_STREAM_Socket' * @param tunnel connection to the other end * @param tunnel_ctx unused * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int client_handle_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = cls; const struct GNUNET_STREAM_AckMessage *ack = (const struct GNUNET_STREAM_AckMessage *) message; return handle_ack (socket, tunnel, sender, ack, atsi); } /** * Message Handler for mesh * * @param cls the server's listen socket * @param tunnel connection to the other end * @param tunnel_ctx pointer to the 'struct GNUNET_STREAM_Socket*' * @param sender who sent the message * @param message the actual message * @param atsi performance data for the connection * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ static int server_handle_ack (void *cls, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity *sender, const struct GNUNET_MessageHeader *message, const struct GNUNET_ATS_Information*atsi) { struct GNUNET_STREAM_Socket *socket = *tunnel_ctx; const struct GNUNET_STREAM_AckMessage *ack = (const struct GNUNET_STREAM_AckMessage *) message; return handle_ack (socket, tunnel, sender, ack, atsi); } /** * For client message handlers, the stream socket is in the * closure argument. */ static struct GNUNET_MESH_MessageHandler client_message_handlers[] = { {&client_handle_data, GNUNET_MESSAGE_TYPE_STREAM_DATA, 0}, {&client_handle_ack, GNUNET_MESSAGE_TYPE_STREAM_ACK, sizeof (struct GNUNET_STREAM_AckMessage) }, {&client_handle_hello_ack, GNUNET_MESSAGE_TYPE_STREAM_HELLO_ACK, sizeof (struct GNUNET_STREAM_HelloAckMessage)}, {&client_handle_reset, GNUNET_MESSAGE_TYPE_STREAM_RESET, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&client_handle_transmit_close, GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&client_handle_transmit_close_ack, GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE_ACK, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&client_handle_receive_close, GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&client_handle_receive_close_ack, GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE_ACK, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&client_handle_close, GNUNET_MESSAGE_TYPE_STREAM_CLOSE, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&client_handle_close_ack, GNUNET_MESSAGE_TYPE_STREAM_CLOSE_ACK, sizeof (struct GNUNET_STREAM_MessageHeader)}, {NULL, 0, 0} }; /** * For server message handlers, the stream socket is in the * tunnel context, and the listen socket in the closure argument. */ static struct GNUNET_MESH_MessageHandler server_message_handlers[] = { {&server_handle_data, GNUNET_MESSAGE_TYPE_STREAM_DATA, 0}, {&server_handle_ack, GNUNET_MESSAGE_TYPE_STREAM_ACK, sizeof (struct GNUNET_STREAM_AckMessage) }, {&server_handle_hello, GNUNET_MESSAGE_TYPE_STREAM_HELLO, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_hello_ack, GNUNET_MESSAGE_TYPE_STREAM_HELLO_ACK, sizeof (struct GNUNET_STREAM_HelloAckMessage)}, {&server_handle_reset, GNUNET_MESSAGE_TYPE_STREAM_RESET, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_transmit_close, GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_transmit_close_ack, GNUNET_MESSAGE_TYPE_STREAM_TRANSMIT_CLOSE_ACK, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_receive_close, GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_receive_close_ack, GNUNET_MESSAGE_TYPE_STREAM_RECEIVE_CLOSE_ACK, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_close, GNUNET_MESSAGE_TYPE_STREAM_CLOSE, sizeof (struct GNUNET_STREAM_MessageHeader)}, {&server_handle_close_ack, GNUNET_MESSAGE_TYPE_STREAM_CLOSE_ACK, sizeof (struct GNUNET_STREAM_MessageHeader)}, {NULL, 0, 0} }; /** * Function called when our target peer is connected to our tunnel * * @param cls the socket for which this tunnel is created * @param peer the peer identity of the target * @param atsi performance data for the connection */ static void mesh_peer_connect_callback (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_ATS_Information * atsi) { struct GNUNET_STREAM_Socket *socket = cls; struct GNUNET_STREAM_MessageHeader *message; if (0 != memcmp (&socket->other_peer, peer, sizeof (struct GNUNET_PeerIdentity))) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "A peer (%s) which is not our target has connected to our tunnel", GNUNET_i2s (peer)); return; } GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Target peer %s connected\n", GNUNET_i2s (peer)); /* Set state to INIT */ socket->state = STATE_INIT; /* Send HELLO message */ message = GNUNET_malloc (sizeof (struct GNUNET_STREAM_MessageHeader)); message->header.type = htons (GNUNET_MESSAGE_TYPE_STREAM_HELLO); message->header.size = htons (sizeof (struct GNUNET_STREAM_MessageHeader)); queue_message (socket, message, &set_state_hello_wait, NULL); /* Call open callback */ if (NULL == socket->open_cb) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "STREAM_open callback is NULL\n"); } else { socket->open_cb (socket->open_cls, socket); } } /** * Function called when our target peer is disconnected from our tunnel * * @param cls the socket associated which this tunnel * @param peer the peer identity of the target */ static void mesh_peer_disconnect_callback (void *cls, const struct GNUNET_PeerIdentity *peer) { } /*****************/ /* API functions */ /*****************/ /** * Tries to open a stream to the target peer * * @param cfg configuration to use * @param target the target peer to which the stream has to be opened * @param app_port the application port number which uniquely identifies this * stream * @param open_cb this function will be called after stream has be established * @param open_cb_cls the closure for open_cb * @param ... options to the stream, terminated by GNUNET_STREAM_OPTION_END * @return if successful it returns the stream socket; NULL if stream cannot be * opened */ struct GNUNET_STREAM_Socket * GNUNET_STREAM_open (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_PeerIdentity *target, GNUNET_MESH_ApplicationType app_port, GNUNET_STREAM_OpenCallback open_cb, void *open_cb_cls, ...) { struct GNUNET_STREAM_Socket *socket; enum GNUNET_STREAM_Option option; va_list vargs; /* Variable arguments */ socket = GNUNET_malloc (sizeof (struct GNUNET_STREAM_Socket)); socket->other_peer = *target; socket->open_cb = open_cb; socket->open_cls = open_cb_cls; /* Set defaults */ socket->retransmit_timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, default_timeout); va_start (vargs, open_cb_cls); /* Parse variable args */ do { option = va_arg (vargs, enum GNUNET_STREAM_Option); switch (option) { case GNUNET_STREAM_OPTION_INITIAL_RETRANSMIT_TIMEOUT: /* Expect struct GNUNET_TIME_Relative */ socket->retransmit_timeout = va_arg (vargs, struct GNUNET_TIME_Relative); break; case GNUNET_STREAM_OPTION_END: break; } } while (GNUNET_STREAM_OPTION_END != option); va_end (vargs); /* End of variable args parsing */ socket->mesh = GNUNET_MESH_connect (cfg, /* the configuration handle */ 1, /* QUEUE size as parameter? */ socket, /* cls */ NULL, /* No inbound tunnel handler */ NULL, /* No inbound tunnel cleaner */ client_message_handlers, NULL); /* We don't get inbound tunnels */ // FIXME: if (NULL == socket->mesh) ... /* Now create the mesh tunnel to target */ socket->tunnel = GNUNET_MESH_tunnel_create (socket->mesh, NULL, /* Tunnel context */ &mesh_peer_connect_callback, &mesh_peer_disconnect_callback, socket); // FIXME: if (NULL == socket->tunnel) ... return socket; } /** * Closes the stream * * @param socket the stream socket */ void GNUNET_STREAM_close (struct GNUNET_STREAM_Socket *socket) { struct MessageQueue *head; /* Clear Transmit handles */ if (NULL != socket->transmit_handle) { GNUNET_MESH_notify_transmit_ready_cancel (socket->transmit_handle); socket->transmit_handle = NULL; } /* Clear existing message queue */ while (NULL != (head = socket->queue_head)) { GNUNET_CONTAINER_DLL_remove (socket->queue_head, socket->queue_tail, head); GNUNET_free (head->message); GNUNET_free (head); } /* Close associated tunnel */ if (NULL != socket->tunnel) { GNUNET_MESH_tunnel_destroy (socket->tunnel); socket->tunnel = NULL; } /* Close mesh connection */ if (NULL != socket->mesh) { GNUNET_MESH_disconnect (socket->mesh); socket->mesh = NULL; } /* Release receive buffer */ if (NULL != socket->receive_buffer) { GNUNET_free (socket->receive_buffer); } GNUNET_free (socket); } /** * Method called whenever a peer creates a tunnel to us * * @param cls closure * @param tunnel new handle to the tunnel * @param initiator peer that started the tunnel * @param atsi performance information for the tunnel * @return initial tunnel context for the tunnel * (can be NULL -- that's not an error) */ static void * new_tunnel_notify (void *cls, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_PeerIdentity *initiator, const struct GNUNET_ATS_Information *atsi) { struct GNUNET_STREAM_ListenSocket *lsocket = cls; struct GNUNET_STREAM_Socket *socket; socket = GNUNET_malloc (sizeof (struct GNUNET_STREAM_Socket)); socket->tunnel = tunnel; socket->session_id = 0; /* FIXME */ socket->other_peer = *initiator; socket->state = STATE_INIT; if (GNUNET_SYSERR == lsocket->listen_cb (lsocket->listen_cb_cls, socket, &socket->other_peer)) { socket->state = STATE_CLOSED; /* FIXME: Send CLOSE message and then free */ GNUNET_free (socket); GNUNET_MESH_tunnel_destroy (tunnel); /* Destroy the tunnel */ } return socket; } /** * Function called whenever an inbound tunnel is destroyed. Should clean up * any associated state. This function is NOT called if the client has * explicitly asked for the tunnel to be destroyed using * GNUNET_MESH_tunnel_destroy. It must NOT call GNUNET_MESH_tunnel_destroy on * the tunnel. * * @param cls closure (set from GNUNET_MESH_connect) * @param tunnel connection to the other end (henceforth invalid) * @param tunnel_ctx place where local state associated * with the tunnel is stored */ static void tunnel_cleaner (void *cls, const struct GNUNET_MESH_Tunnel *tunnel, void *tunnel_ctx) { struct GNUNET_STREAM_Socket *socket = tunnel_ctx; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer %s has terminated connection abruptly\n", GNUNET_i2s (&socket->other_peer)); socket->status = GNUNET_STREAM_SHUTDOWN; /* Clear Transmit handles */ if (NULL != socket->transmit_handle) { GNUNET_MESH_notify_transmit_ready_cancel (socket->transmit_handle); socket->transmit_handle = NULL; } socket->tunnel = NULL; } /** * Listens for stream connections for a specific application ports * * @param cfg the configuration to use * @param app_port the application port for which new streams will be accepted * @param listen_cb this function will be called when a peer tries to establish * a stream with us * @param listen_cb_cls closure for listen_cb * @return listen socket, NULL for any error */ struct GNUNET_STREAM_ListenSocket * GNUNET_STREAM_listen (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_MESH_ApplicationType app_port, GNUNET_STREAM_ListenCallback listen_cb, void *listen_cb_cls) { /* FIXME: Add variable args for passing configration options? */ struct GNUNET_STREAM_ListenSocket *lsocket; GNUNET_MESH_ApplicationType app_types[2]; app_types[0] = app_port; app_types[1] = 0; lsocket = GNUNET_malloc (sizeof (struct GNUNET_STREAM_ListenSocket)); lsocket->port = app_port; lsocket->listen_cb = listen_cb; lsocket->listen_cb_cls = listen_cb_cls; lsocket->mesh = GNUNET_MESH_connect (cfg, 10, /* FIXME: QUEUE size as parameter? */ lsocket, /* Closure */ &new_tunnel_notify, &tunnel_cleaner, server_message_handlers, app_types); return lsocket; } /** * Closes the listen socket * * @param lsocket the listen socket */ void GNUNET_STREAM_listen_close (struct GNUNET_STREAM_ListenSocket *lsocket) { /* Close MESH connection */ GNUNET_MESH_disconnect (lsocket->mesh); GNUNET_free (lsocket); } /** * Tries to write the given data to the stream * * @param socket the socket representing a stream * @param data the data buffer from where the data is written into the stream * @param size the number of bytes to be written from the data buffer * @param timeout the timeout period * @param write_cont the function to call upon writing some bytes into the stream * @param write_cont_cls the closure * @return handle to cancel the operation */ struct GNUNET_STREAM_IOHandle * GNUNET_STREAM_write (struct GNUNET_STREAM_Socket *socket, const void *data, size_t size, struct GNUNET_TIME_Relative timeout, GNUNET_STREAM_CompletionContinuation write_cont, void *write_cont_cls) { unsigned int num_needed_packets; unsigned int packet; struct GNUNET_STREAM_IOHandle *io_handle; size_t packet_size; struct GNUNET_STREAM_DataMessage *data_msg; const void *sweep; /* Return NULL if there is already a write request pending */ if (NULL != socket->write_handle) { GNUNET_break (0); return NULL; } if (!((STATE_ESTABLISHED == socket->state) || (STATE_RECEIVE_CLOSE_WAIT == socket->state) || (STATE_RECEIVE_CLOSED == socket->state))) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Attempting to write on a closed (OR) not-yet-established" "stream\n"); return NULL; } if (GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH * max_payload_size < size) size = GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH * max_payload_size; num_needed_packets = (size + (max_payload_size - 1)) / max_payload_size; io_handle = GNUNET_malloc (sizeof (struct GNUNET_STREAM_IOHandle)); io_handle->receive_window_available = socket->receive_window_available; sweep = data; /* Divide the given buffer into packets for sending */ for (packet=0; packet < num_needed_packets; packet++) { if ((packet + 1) * max_payload_size < size) { packet_size = MAX_PACKET_SIZE; } else { packet_size = size - packet * max_payload_size + sizeof (struct GNUNET_STREAM_DataMessage); } io_handle->messages[packet] = GNUNET_malloc (packet_size); io_handle->messages[packet]->header.header.size = htons (packet_size); io_handle->messages[packet]->header.header.type = htons (GNUNET_MESSAGE_TYPE_STREAM_DATA); io_handle->messages[packet]->sequence_number = htons (socket->write_sequence_number++); /* FIXME: Remove the fixed delay for ack deadline; Set it to the value determined from RTT */ io_handle->messages[packet]->ack_deadline = GNUNET_TIME_relative_hton (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)); data_msg = io_handle->messages[packet]; /* Copy data from given buffer to the packet */ memcpy (&data_msg[1], sweep, packet_size - sizeof (struct GNUNET_STREAM_DataMessage)); sweep += packet_size - sizeof (struct GNUNET_STREAM_DataMessage); } socket->write_handle = io_handle; write_data (socket); return io_handle; } /** * Tries to read data from the stream * * @param socket the socket representing a stream * @param timeout the timeout period * @param proc function to call with data (once only) * @param proc_cls the closure for proc * @return handle to cancel the operation */ struct GNUNET_STREAM_IOHandle * GNUNET_STREAM_read (const struct GNUNET_STREAM_Socket *socket, struct GNUNET_TIME_Relative timeout, GNUNET_STREAM_DataProcessor proc, void *proc_cls) { /* Check the bitmap for any holes */ /* Deem the data from the starting of the bitmap upto a hole as available data */ /* Create an IO handle */ /* Call the Data processor with this available data */ /* Update the read_sequence_number to the first hole in the bitmap */ /* Shift the bitmap so that the first hole is now at the start */ }