/* This file is part of GNUnet. Copyright (C) 2010-2015 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 transport/gnunet-service-transport_neighbours.c * @brief neighbour management * @author Christian Grothoff */ #include "platform.h" #include "gnunet_ats_service.h" #include "gnunet-service-transport_ats.h" #include "gnunet-service-transport_blacklist.h" #include "gnunet-service-transport_clients.h" #include "gnunet-service-transport_neighbours.h" #include "gnunet-service-transport_manipulation.h" #include "gnunet-service-transport_plugins.h" #include "gnunet-service-transport_validation.h" #include "gnunet-service-transport.h" #include "gnunet_peerinfo_service.h" #include "gnunet_constants.h" #include "transport.h" /** * Size of the neighbour hash map. */ #define NEIGHBOUR_TABLE_SIZE 256 /** * Time we give plugin to transmit DISCONNECT message before the * neighbour entry self-destructs. */ #define DISCONNECT_SENT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 500) /** * How often must a peer violate bandwidth quotas before we start * to simply drop its messages? */ #define QUOTA_VIOLATION_DROP_THRESHOLD 10 /** * How long are we willing to wait for a response from ATS before timing out? */ #define ATS_RESPONSE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5) /** * How long are we willing to wait for an ACK from the other peer before * giving up on our connect operation? */ #define SETUP_CONNECTION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15) /** * How long are we willing to wait for a successful reconnect if * an existing connection went down? Much shorter than the * usual SETUP_CONNECTION_TIMEOUT as we do not inform the * higher layers about the disconnect during this period. */ #define FAST_RECONNECT_TIMEOUT GNUNET_TIME_UNIT_SECONDS /** * Interval to send utilization data */ #define UTIL_TRANSMISSION_INTERVAL GNUNET_TIME_UNIT_SECONDS /** * State describing which kind a reply this neighbour should send */ enum GST_ACK_State { /** * We did not receive a SYN message for this neighbour */ ACK_UNDEFINED = 0, /** * The neighbour received a SYN message and has to send a SYN_ACK * as reply */ ACK_SEND_SYN_ACK = 1, /** * The neighbour sent a SYN_ACK message and has to send a ACK * as reply */ ACK_SEND_ACK = 2 }; GNUNET_NETWORK_STRUCT_BEGIN /** * Message a peer sends to another to indicate that it intends to * setup a connection/session for data exchange. A 'SESSION_SYN' * should be answered with a 'SESSION_SYN_ACK' with the same body * to confirm. A 'SESSION_SYN_ACK' should then be followed with * a 'ACK'. Once the 'ACK' is received, both peers * should be connected. */ struct TransportSynMessage { /** * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN * or #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN_ACK */ struct GNUNET_MessageHeader header; /** * Always zero. */ uint32_t reserved GNUNET_PACKED; /** * Absolute time at the sender. Only the most recent connect * message implies which session is preferred by the sender. */ struct GNUNET_TIME_AbsoluteNBO timestamp; }; /** * Message a peer sends to another when connected to indicate that a * session is in use and the peer is still alive or to respond to a keep alive. * A peer sends a message with type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE * to request a message with #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE. * When the keep alive response with type is received, transport service * will call the respective plugin to update the session timeout */ struct SessionKeepAliveMessage { /** * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE or * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE. */ struct GNUNET_MessageHeader header; /** * A nonce to identify the session the keep alive is used for */ uint32_t nonce GNUNET_PACKED; }; /** * Message a peer sends to another when connected to indicate that * the other peer should limit transmissions to the indicated * quota. */ struct SessionQuotaMessage { /** * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_QUOTA. */ struct GNUNET_MessageHeader header; /** * Quota to use (for sending), in bytes per second. */ uint32_t quota GNUNET_PACKED; }; /** * Message we send to the other peer to notify him that we intentionally * are disconnecting (to reduce timeouts). This is just a friendly * notification, peers must not rely on always receiving disconnect * messages. */ struct SessionDisconnectMessage { /** * Header of type #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT */ struct GNUNET_MessageHeader header; /** * Always zero. */ uint32_t reserved GNUNET_PACKED; /** * Purpose of the signature. Extends over the timestamp. * Purpose should be #GNUNET_SIGNATURE_PURPOSE_TRANSPORT_DISCONNECT. */ struct GNUNET_CRYPTO_EccSignaturePurpose purpose; /** * Absolute time at the sender. Only the most recent connect * message implies which session is preferred by the sender. */ struct GNUNET_TIME_AbsoluteNBO timestamp; /** * Public key of the sender. */ struct GNUNET_CRYPTO_EddsaPublicKey public_key; /** * Signature of the peer that sends us the disconnect. Only * valid if the timestamp is AFTER the timestamp from the * corresponding 'SYN' message. */ struct GNUNET_CRYPTO_EddsaSignature signature; }; GNUNET_NETWORK_STRUCT_END /** * For each neighbour we keep a list of messages * that we still want to transmit to the neighbour. */ struct MessageQueue { /** * This is a doubly linked list. */ struct MessageQueue *next; /** * This is a doubly linked list. */ struct MessageQueue *prev; /** * Function to call once we're done. */ GST_NeighbourSendContinuation cont; /** * Closure for @e cont */ void *cont_cls; /** * The message(s) we want to transmit, GNUNET_MessageHeader(s) * stuck together in memory. Allocated at the end of this struct. */ const char *message_buf; /** * Size of the message buf */ size_t message_buf_size; /** * At what time should we fail? */ struct GNUNET_TIME_Absolute timeout; }; /** * A possible address we could use to communicate with a neighbour. */ struct NeighbourAddress { /** * Active session for this address. */ struct Session *session; /** * Network-level address information. */ struct GNUNET_HELLO_Address *address; /** * Timestamp of the 'SESSION_CONNECT' message we sent to the other * peer for this address. Use to check that the ACK is in response * to our most recent 'SYN'. */ struct GNUNET_TIME_Absolute connect_timestamp; /** * Inbound bandwidth from ATS for this address. */ struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in; /** * Outbound bandwidth from ATS for this address. */ struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out; /** * Did we tell ATS that this is our 'active' address? */ int ats_active; /** * The current nonce sent in the last keep alive messages */ uint32_t keep_alive_nonce; }; /** * Entry in neighbours. */ struct NeighbourMapEntry { /** * Head of list of messages we would like to send to this peer; * must contain at most one message per client. */ struct MessageQueue *messages_head; /** * Tail of list of messages we would like to send to this peer; must * contain at most one message per client. */ struct MessageQueue *messages_tail; /** * Are we currently trying to send a message? If so, which one? */ struct MessageQueue *is_active; /** * Primary address we currently use to communicate with the neighbour. */ struct NeighbourAddress primary_address; /** * Alternative address currently under consideration for communicating * with the neighbour. */ struct NeighbourAddress alternative_address; /** * Identity of this neighbour. */ struct GNUNET_PeerIdentity id; /** * Main task that drives this peer (timeouts, keepalives, etc.). * Always runs the #master_task(). */ struct GNUNET_SCHEDULER_Task *task; /** * Task to disconnect neighbour after we received a DISCONNECT message */ struct GNUNET_SCHEDULER_Task *delayed_disconnect_task; /** * At what time should we sent the next keep-alive message? */ struct GNUNET_TIME_Absolute keep_alive_time; /** * At what time did we sent the last keep-alive message? Used * to calculate round-trip time ("latency"). */ struct GNUNET_TIME_Absolute last_keep_alive_time; /** * Timestamp we should include in our next SYN_ACK message. * (only valid if 'send_connect_ack' is #GNUNET_YES). Used to build * our SYN_ACK message. */ struct GNUNET_TIME_Absolute connect_ack_timestamp; /** * ATS address suggest handle */ struct GNUNET_ATS_ConnectivitySuggestHandle *suggest_handle; /** * Time where we should cut the connection (timeout) if we don't * make progress in the state machine (or get a KEEPALIVE_RESPONSE * if we are in #GNUNET_TRANSPORT_PS_CONNECTED). */ struct GNUNET_TIME_Absolute timeout; /** * Tracker for inbound bandwidth. */ struct GNUNET_BANDWIDTH_Tracker in_tracker; /** * How often has the other peer (recently) violated the inbound * traffic limit? Incremented by 10 per violation, decremented by 1 * per non-violation (for each time interval). */ unsigned int quota_violation_count; /** * Latest quota the other peer send us in bytes per second. * We should not send more, least the other peer throttle * receiving our traffic. */ struct GNUNET_BANDWIDTH_Value32NBO neighbour_receive_quota; /** * The current state of the peer. */ enum GNUNET_TRANSPORT_PeerState state; /** * Did we sent an KEEP_ALIVE message and are we expecting a response? */ int expect_latency_response; /** * When a peer wants to connect we have to reply to the 1st SYN message * with a SYN_ACK message. But sometime we cannot send this message * immediately since we do not have an address and then we have to remember * to send this message as soon as we have an address. * * Flag to set if we still need to send a SYN_ACK message to the other peer * (once we have an address to use and the peer has been allowed by our * blacklist). Initially set to #ACK_UNDEFINED. Set to #ACK_SEND_SYN_ACK * if we need to send a SYN_ACK. Set to #ACK_SEND_ACK if we did * send a SYN_ACK and should go to #S_CONNECTED upon receiving a * 'ACK' (regardless of what our own state machine might say). */ enum GST_ACK_State ack_state; /** * Tracking utilization of outbound bandwidth */ uint32_t util_total_bytes_sent; /** * Tracking utilization of inbound bandwidth */ uint32_t util_total_bytes_recv; /** * Date of last utilization transmission */ struct GNUNET_TIME_Absolute last_util_transmission; }; /** * Context for blacklist checks and the #try_connect_bl_check_cont() * function. Stores information about ongoing blacklist checks. */ struct BlackListCheckContext { /** * We keep blacklist checks in a DLL. */ struct BlackListCheckContext *next; /** * We keep blacklist checks in a DLL. */ struct BlackListCheckContext *prev; /** * Address that is being checked. */ struct NeighbourAddress na; /** * Handle to the ongoing blacklist check. */ struct GST_BlacklistCheck *bc; }; /** * Hash map from peer identities to the respective `struct NeighbourMapEntry`. */ static struct GNUNET_CONTAINER_MultiPeerMap *neighbours; /** * We keep blacklist checks in a DLL so that we can find * the 'sessions' in their 'struct NeighbourAddress' if * a session goes down. */ static struct BlackListCheckContext *bc_head; /** * We keep blacklist checks in a DLL. */ static struct BlackListCheckContext *bc_tail; /** * List of pending blacklist checks: head */ static struct BlacklistCheckSwitchContext *pending_bc_head; /** * List of pending blacklist checks: tail */ static struct BlacklistCheckSwitchContext *pending_bc_tail; /** * counter for connected neighbours */ static unsigned int neighbours_connected; /** * Number of bytes we have currently queued for transmission. */ static unsigned long long bytes_in_send_queue; /** * Task transmitting utilization data */ static struct GNUNET_SCHEDULER_Task *util_transmission_tk; /** * Convert the given ACK state to a string. * * @param s state * @return corresponding human-readable string */ static char * print_ack_state (enum GST_ACK_State s) { switch (s) { case ACK_UNDEFINED: return "UNDEFINED"; case ACK_SEND_SYN_ACK: return "SEND_SYN_ACK"; case ACK_SEND_ACK: return "SEND_ACK"; default: GNUNET_break (0); return "N/A"; } } /** * Notify our clients that another peer connected to us. * * @param peer the peer that connected * @param bandwidth_in inbound bandwidth in NBO * @param bandwidth_out outbound bandwidth in NBO */ static void neighbours_connect_notification (const struct GNUNET_PeerIdentity *peer, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out) { size_t len = sizeof(struct ConnectInfoMessage); char buf[len] GNUNET_ALIGN; struct ConnectInfoMessage *connect_msg = (struct ConnectInfoMessage *) buf; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "We are now connected to peer `%s'\n", GNUNET_i2s (peer)); connect_msg->header.size = htons (sizeof(buf)); connect_msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT); connect_msg->id = *peer; connect_msg->quota_in = bandwidth_in; connect_msg->quota_out = bandwidth_out; GST_clients_broadcast (&connect_msg->header, GNUNET_NO); } /** * Notify our clients (and manipulation) that a peer disconnected from * us. * * @param peer the peer that disconnected */ static void neighbours_disconnect_notification (const struct GNUNET_PeerIdentity *peer) { struct DisconnectInfoMessage disconnect_msg; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Peer `%s' disconnected\n", GNUNET_i2s (peer)); GST_manipulation_peer_disconnect (peer); disconnect_msg.header.size = htons (sizeof(struct DisconnectInfoMessage)); disconnect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT); disconnect_msg.reserved = htonl (0); disconnect_msg.peer = *peer; GST_clients_broadcast (&disconnect_msg.header, GNUNET_NO); } /** * Notify transport clients that a neighbour peer changed its active * address. * * @param peer identity of the peer * @param address address possibly NULL if peer is not connected * @param state current state this peer is in * @param state_timeout timeout for the current state of the peer * @param bandwidth_in bandwidth assigned inbound, 0 on disconnect * @param bandwidth_out bandwidth assigned outbound, 0 on disconnect */ static void neighbours_changed_notification (const struct GNUNET_PeerIdentity *peer, const struct GNUNET_HELLO_Address *address, enum GNUNET_TRANSPORT_PeerState state, struct GNUNET_TIME_Absolute state_timeout, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Notifying about change for peer `%s' with address `%s' in state `%s' timing out at %s\n", GNUNET_i2s (peer), GST_plugins_a2s (address), GNUNET_TRANSPORT_ps2s (state), GNUNET_STRINGS_absolute_time_to_string (state_timeout)); /* FIXME: include bandwidth in notification! */ GST_clients_broadcast_peer_notification (peer, address, state, state_timeout); } /** * Lookup a neighbour entry in the neighbours hash map. * * @param pid identity of the peer to look up * @return the entry, NULL if there is no existing record */ static struct NeighbourMapEntry * lookup_neighbour (const struct GNUNET_PeerIdentity *pid) { if (NULL == neighbours) return NULL; return GNUNET_CONTAINER_multipeermap_get (neighbours, pid); } /** * Test if we're connected to the given peer. * * @param n neighbour entry of peer to test * @return #GNUNET_YES if we are connected, #GNUNET_NO if not */ static int test_connected (struct NeighbourMapEntry *n) { if (NULL == n) return GNUNET_NO; return GNUNET_TRANSPORT_is_connected (n->state); } /** * Send information about a new outbound quota to our clients. * Note that the outbound quota is enforced client-side (i.e. * in libgnunettransport). * * @param target affected peer * @param quota new quota */ static void send_outbound_quota_to_clients (const struct GNUNET_PeerIdentity *target, struct GNUNET_BANDWIDTH_Value32NBO quota) { struct QuotaSetMessage q_msg; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending outbound quota of %u Bps for peer `%s' to all clients\n", ntohl (quota.value__), GNUNET_i2s (target)); q_msg.header.size = htons (sizeof (struct QuotaSetMessage)); q_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA); q_msg.quota = quota; q_msg.peer = (*target); GST_clients_broadcast (&q_msg.header, GNUNET_NO); } /** * We don't need a given neighbour address any more. * Release its resources and give appropriate notifications * to ATS and other subsystems. * * @param na address we are done with; @a na itself must NOT be 'free'd, only the contents! */ static void free_address (struct NeighbourAddress *na) { if (GNUNET_YES == na->ats_active) GST_validation_set_address_use (na->address, GNUNET_NO); if (NULL != na->address) { GST_ats_block_address (na->address, na->session); GNUNET_HELLO_address_free (na->address); na->address = NULL; } na->bandwidth_in = GNUNET_BANDWIDTH_value_init (0); na->bandwidth_out = GNUNET_BANDWIDTH_value_init (0); na->ats_active = GNUNET_NO; na->keep_alive_nonce = 0; na->session = NULL; } /** * Master task run for every neighbour. Performs all of the time-related * activities (keep alive, send next message, disconnect if idle, finish * clean up after disconnect). * * @param cls the `struct NeighbourMapEntry` for which we are running * @param tc scheduler context (unused) */ static void master_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc); /** * Set net state and state timeout for this neighbour and notify monitoring * * @param n the respective neighbour * @param s the new state * @param timeout the new timeout */ static void set_state_and_timeout (struct NeighbourMapEntry *n, enum GNUNET_TRANSPORT_PeerState s, struct GNUNET_TIME_Absolute timeout) { if (GNUNET_TRANSPORT_is_connected (s) && ! GNUNET_TRANSPORT_is_connected (n->state) ) { neighbours_connect_notification (&n->id, n->primary_address.bandwidth_in, n->primary_address.bandwidth_out); GNUNET_STATISTICS_set (GST_stats, gettext_noop ("# peers connected"), ++neighbours_connected, GNUNET_NO); } if (! GNUNET_TRANSPORT_is_connected (s) && GNUNET_TRANSPORT_is_connected (n->state) ) { GNUNET_STATISTICS_set (GST_stats, gettext_noop ("# peers connected"), --neighbours_connected, GNUNET_NO); neighbours_disconnect_notification (&n->id); } n->state = s; if ( (timeout.abs_value_us < n->timeout.abs_value_us) && (NULL != n->task ) ) { /* new timeout is earlier, reschedule master task */ GNUNET_SCHEDULER_cancel (n->task); n->task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining (timeout), &master_task, n); } n->timeout = timeout; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' changed state to %s with timeout %s\n", GNUNET_i2s (&n->id), GNUNET_TRANSPORT_ps2s(s), GNUNET_STRINGS_absolute_time_to_string (timeout)); neighbours_changed_notification (&n->id, n->primary_address.address, n->state, n->timeout, n->primary_address.bandwidth_in, n->primary_address.bandwidth_out); } /** * Initialize the alternative address of a neighbour * * @param n the neighbour * @param address address of the other peer, NULL if other peer * connected to us * @param session session to use (or NULL, in which case an * address must be setup) * @param bandwidth_in inbound quota to be used when connection is up * @param bandwidth_out outbound quota to be used when connection is up */ static void set_alternative_address (struct NeighbourMapEntry *n, const struct GNUNET_HELLO_Address *address, struct Session *session, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out) { struct GNUNET_TRANSPORT_PluginFunctions *papi; if (NULL == (papi = GST_plugins_find (address->transport_name))) { GNUNET_break (0); return; } if (session == n->alternative_address.session) { n->alternative_address.bandwidth_in = bandwidth_in; n->alternative_address.bandwidth_out = bandwidth_out; return; } if (NULL != n->alternative_address.address) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Replacing existing alternative address with another one\n"); free_address (&n->alternative_address); } if (NULL == session) session = papi->get_session (papi->cls, address); if (NULL == session) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Failed to obtain new session for peer `%s' and address '%s'\n", GNUNET_i2s (&address->peer), GST_plugins_a2s (address)); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# session creation failed"), 1, GNUNET_NO); return; } GST_ats_new_session (address, session); GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' configured alternative address %s\n", GNUNET_i2s (&n->id), GST_plugins_a2s(address)); n->alternative_address.address = GNUNET_HELLO_address_copy (address); n->alternative_address.bandwidth_in = bandwidth_in; n->alternative_address.bandwidth_out = bandwidth_out; n->alternative_address.session = session; n->alternative_address.ats_active = GNUNET_NO; n->alternative_address.keep_alive_nonce = 0; GNUNET_assert (GNUNET_YES == GST_ats_is_known (n->alternative_address.address, n->alternative_address.session)); } /** * Initialize the primary address of a neighbour * * @param n the neighbour * @param address address of the other peer, NULL if other peer * connected to us * @param session session to use (or NULL, in which case an * address must be setup) * @param bandwidth_in inbound quota to be used when connection is up * @param bandwidth_out outbound quota to be used when connection is up */ static void set_primary_address (struct NeighbourMapEntry *n, const struct GNUNET_HELLO_Address *address, struct Session *session, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out) { if (session == n->primary_address.session) { GST_validation_set_address_use (n->primary_address.address, GNUNET_YES); if (n->primary_address.bandwidth_in.value__ != bandwidth_in.value__) { n->primary_address.bandwidth_in = bandwidth_in; GST_neighbours_set_incoming_quota (&address->peer, bandwidth_in); } if (n->primary_address.bandwidth_out.value__ != bandwidth_out.value__) { n->primary_address.bandwidth_out = bandwidth_out; send_outbound_quota_to_clients (&address->peer, bandwidth_out); } return; } if ( (NULL != n->primary_address.address) && (0 == GNUNET_HELLO_address_cmp (address, n->primary_address.address)) ) { GNUNET_break (0); return; } if (NULL == session) { GNUNET_break (0); GST_ats_block_address (address, session); return; } if (NULL != n->primary_address.address) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Replacing existing primary address with another one\n"); free_address (&n->primary_address); } n->primary_address.address = GNUNET_HELLO_address_copy (address); n->primary_address.bandwidth_in = bandwidth_in; n->primary_address.bandwidth_out = bandwidth_out; n->primary_address.session = session; n->primary_address.keep_alive_nonce = 0; GNUNET_assert (GNUNET_YES == GST_ats_is_known (n->primary_address.address, n->primary_address.session)); /* subsystems about address use */ GST_validation_set_address_use (n->primary_address.address, GNUNET_YES); GST_neighbours_set_incoming_quota (&address->peer, bandwidth_in); send_outbound_quota_to_clients (&address->peer, bandwidth_out); GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Neighbour `%s' switched to address `%s'\n", GNUNET_i2s (&n->id), GST_plugins_a2s(address)); neighbours_changed_notification (&n->id, n->primary_address.address, n->state, n->timeout, n->primary_address.bandwidth_in, n->primary_address.bandwidth_out); } /** * Clear the primary address of a neighbour since this address is not * valid anymore and notify monitoring about it * * @param n the neighbour */ static void unset_primary_address (struct NeighbourMapEntry *n) { /* Notify monitoring about change */ if (NULL == n->primary_address.address) return; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Disabling primary address\n"); neighbours_changed_notification (&n->id, n->primary_address.address, n->state, n->timeout, GNUNET_BANDWIDTH_value_init (0), GNUNET_BANDWIDTH_value_init (0)); free_address (&n->primary_address); } /** * Free a neighbour map entry. * * @param n entry to free */ static void free_neighbour (struct NeighbourMapEntry *n) { struct MessageQueue *mq; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Freeing neighbour state of peer `%s'\n", GNUNET_i2s (&n->id)); n->is_active = NULL; /* always free'd by its own continuation! */ /* fail messages currently in the queue */ while (NULL != (mq = n->messages_head)) { GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq); if (NULL != mq->cont) mq->cont (mq->cont_cls, GNUNET_SYSERR, mq->message_buf_size, 0); GNUNET_free (mq); } /* Mark peer as disconnected */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED, GNUNET_TIME_UNIT_FOREVER_ABS); /* free addresses and mark as unused */ unset_primary_address (n); if (NULL != n->alternative_address.address) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Cleaning up alternative address\n"); free_address (&n->alternative_address); } GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multipeermap_remove (neighbours, &n->id, n)); /* Cancel address requests for this peer */ if (NULL != n->suggest_handle) { GNUNET_ATS_connectivity_suggest_cancel (n->suggest_handle); n->suggest_handle = NULL; } /* Cancel the disconnect task */ if (NULL != n->delayed_disconnect_task) { GNUNET_SCHEDULER_cancel (n->delayed_disconnect_task); n->delayed_disconnect_task = NULL; } /* Cancel the master task */ if (NULL != n->task) { GNUNET_SCHEDULER_cancel (n->task); n->task = NULL; } /* free rest of memory */ GNUNET_free (n); } /** * Transmit a message using the current session of the given * neighbour. * * @param n entry for the recipient * @param msgbuf buffer to transmit * @param msgbuf_size number of bytes in @a msgbuf buffer * @param priority transmission priority * @param timeout transmission timeout * @param use_keepalive_timeout #GNUNET_YES to use plugin-specific keep-alive * timeout (@a timeout is ignored in that case), #GNUNET_NO otherwise * @param cont continuation to call when finished (can be NULL) * @param cont_cls closure for @a cont * @return timeout (copy of @a timeout or a calculated one if * @a use_keepalive_timeout is #GNUNET_YES. */ static struct GNUNET_TIME_Relative send_with_session (struct NeighbourMapEntry *n, const void *msgbuf, size_t msgbuf_size, uint32_t priority, struct GNUNET_TIME_Relative timeout, unsigned int use_keepalive_timeout, GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls) { struct GNUNET_TRANSPORT_PluginFunctions *papi; struct GNUNET_TIME_Relative result = GNUNET_TIME_UNIT_FOREVER_REL; GNUNET_assert (NULL != n->primary_address.session); if ( ((NULL == (papi = GST_plugins_find (n->primary_address.address->transport_name)) || (-1 == papi->send (papi->cls, n->primary_address.session, msgbuf, msgbuf_size, priority, (result = (GNUNET_NO == use_keepalive_timeout) ? timeout : GNUNET_TIME_relative_divide (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT, papi->query_keepalive_factor (papi->cls))), cont, cont_cls)))) && (NULL != cont)) cont (cont_cls, &n->id, GNUNET_SYSERR, msgbuf_size, 0); GST_neighbours_notify_data_sent (n->primary_address.address, n->primary_address.session, msgbuf_size); GNUNET_break (NULL != papi); return result; } /** * Function called when the 'DISCONNECT' message has been sent by the * plugin. Frees the neighbour --- if the entry still exists. * * @param cls NULL * @param target identity of the neighbour that was disconnected * @param result #GNUNET_OK if the disconnect got out successfully * @param payload bytes payload * @param physical bytes on wire */ static void send_disconnect_cont (void *cls, const struct GNUNET_PeerIdentity *target, int result, size_t payload, size_t physical) { struct NeighbourMapEntry *n; n = lookup_neighbour (target); if (NULL == n) return; /* already gone */ if (GNUNET_TRANSPORT_PS_DISCONNECT != n->state) return; /* have created a fresh entry since */ if (NULL != n->task) GNUNET_SCHEDULER_cancel (n->task); n->task = GNUNET_SCHEDULER_add_now (&master_task, n); } /** * Transmit a DISCONNECT message to the other peer. * * @param n neighbour to send DISCONNECT message. */ static void send_disconnect (struct NeighbourMapEntry *n) { struct SessionDisconnectMessage disconnect_msg; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Sending DISCONNECT message to peer `%4s'\n", GNUNET_i2s (&n->id)); disconnect_msg.header.size = htons (sizeof (struct SessionDisconnectMessage)); disconnect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT); disconnect_msg.reserved = htonl (0); disconnect_msg.purpose.size = htonl (sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) + sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) + sizeof (struct GNUNET_TIME_AbsoluteNBO)); disconnect_msg.purpose.purpose = htonl (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT); disconnect_msg.timestamp = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get ()); disconnect_msg.public_key = GST_my_identity.public_key; GNUNET_assert (GNUNET_OK == GNUNET_CRYPTO_eddsa_sign (GST_my_private_key, &disconnect_msg.purpose, &disconnect_msg.signature)); (void) send_with_session (n, &disconnect_msg, sizeof (disconnect_msg), UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_NO, &send_disconnect_cont, NULL); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# DISCONNECT messages sent"), 1, GNUNET_NO); } /** * Disconnect from the given neighbour, clean up the record. * * @param n neighbour to disconnect from */ static void disconnect_neighbour (struct NeighbourMapEntry *n) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Disconnecting from peer %s in state %s\n", GNUNET_i2s (&n->id), GNUNET_TRANSPORT_ps2s (n->state)); /* depending on state, notify neighbour and/or upper layers of this peer about disconnect */ switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: case GNUNET_TRANSPORT_PS_INIT_ATS: /* other peer is completely unaware of us, no need to send DISCONNECT */ free_neighbour (n); return; case GNUNET_TRANSPORT_PS_SYN_SENT: send_disconnect (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_DISCONNECT, GNUNET_TIME_UNIT_FOREVER_ABS); break; case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: /* we never ACK'ed the other peer's request, no need to send DISCONNECT */ free_neighbour (n); return; case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: /* we DID ACK the other peer's request, must send DISCONNECT */ send_disconnect (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_DISCONNECT, GNUNET_TIME_UNIT_FOREVER_ABS); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: case GNUNET_TRANSPORT_PS_CONNECTED: case GNUNET_TRANSPORT_PS_RECONNECT_SENT: /* we are currently connected, need to send disconnect and do internal notifications and update statistics */ send_disconnect (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_DISCONNECT, GNUNET_TIME_UNIT_FOREVER_ABS); break; case GNUNET_TRANSPORT_PS_RECONNECT_ATS: /* Disconnecting while waiting for an ATS address to reconnect, * cannot send DISCONNECT */ free_neighbour (n); return; case GNUNET_TRANSPORT_PS_DISCONNECT: /* already disconnected, ignore */ break; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: /* already cleaned up, how did we get here!? */ GNUNET_assert (0); break; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); break; } /* schedule timeout to clean up */ if (NULL != n->task) GNUNET_SCHEDULER_cancel (n->task); n->task = GNUNET_SCHEDULER_add_delayed (DISCONNECT_SENT_TIMEOUT, &master_task, n); } /** * We're done with our transmission attempt, continue processing. * * @param cls the `struct MessageQueue` of the message * @param receiver intended receiver * @param success whether it worked or not * @param size_payload bytes payload sent * @param physical bytes sent on wire */ static void transmit_send_continuation (void *cls, const struct GNUNET_PeerIdentity *receiver, int success, size_t size_payload, size_t physical) { struct MessageQueue *mq = cls; struct NeighbourMapEntry *n; if (NULL == (n = lookup_neighbour (receiver))) { if (NULL != mq->cont) mq->cont (mq->cont_cls, GNUNET_SYSERR /* not connected */, size_payload, 0); GNUNET_free (mq); return; /* disconnect or other error while transmitting, can happen */ } if (n->is_active == mq) { /* this is still "our" neighbour, remove us from its queue and allow it to send the next message now */ n->is_active = NULL; if (NULL != n->task) GNUNET_SCHEDULER_cancel (n->task); n->task = GNUNET_SCHEDULER_add_now (&master_task, n); } if (bytes_in_send_queue < mq->message_buf_size) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Bytes_in_send_queue `%u', Message_size %u, result: %s, payload %u, on wire %u\n", bytes_in_send_queue, mq->message_buf_size, (GNUNET_OK == success) ? "OK" : "FAIL", size_payload, physical); GNUNET_break (0); } GNUNET_break (size_payload == mq->message_buf_size); bytes_in_send_queue -= mq->message_buf_size; GNUNET_STATISTICS_set (GST_stats, gettext_noop ("# bytes in message queue for other peers"), bytes_in_send_queue, GNUNET_NO); if (GNUNET_OK == success) GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# messages transmitted to other peers"), 1, GNUNET_NO); else GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# transmission failures for messages to other peers"), 1, GNUNET_NO); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending message to `%s' of type %u with %u bytes was a %s\n", GNUNET_i2s (receiver), ntohs (((struct GNUNET_MessageHeader *) mq->message_buf)->type), mq->message_buf_size, (success == GNUNET_OK) ? "success" : "FAILURE"); if (NULL != mq->cont) mq->cont (mq->cont_cls, success, size_payload, physical); GNUNET_free (mq); } /** * Check the message list for the given neighbour and if we can * send a message, do so. This function should only be called * if the connection is at least generally ready for transmission. * While we will only send one message at a time, no bandwidth * quota management is performed here. If a message was given to * the plugin, the continuation will automatically re-schedule * the 'master' task once the next message might be transmitted. * * @param n target peer for which to transmit */ static void try_transmission_to_peer (struct NeighbourMapEntry *n) { struct MessageQueue *mq; struct GNUNET_TIME_Relative timeout; if (NULL == n->primary_address.address) { /* no address, why are we here? */ GNUNET_break (0); return; } if ((0 == n->primary_address.address->address_length) && (NULL == n->primary_address.session)) { /* no address, why are we here? */ GNUNET_break (0); return; } if (NULL != n->is_active) { /* transmission already pending */ return; } /* timeout messages from the queue that are past their due date */ while (NULL != (mq = n->messages_head)) { timeout = GNUNET_TIME_absolute_get_remaining (mq->timeout); if (timeout.rel_value_us > 0) break; GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# messages timed out while in transport queue"), 1, GNUNET_NO); GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq); n->is_active = mq; transmit_send_continuation (mq, &n->id, GNUNET_SYSERR, mq->message_buf_size, 0); /* timeout */ } if (NULL == mq) return; /* no more messages */ GNUNET_CONTAINER_DLL_remove (n->messages_head, n->messages_tail, mq); n->is_active = mq; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Giving message with %u bytes to plugin session %p\n", mq->message_buf_size, n->primary_address.session); (void) send_with_session (n, mq->message_buf, mq->message_buf_size, 0 /* priority */, timeout, GNUNET_NO, &transmit_send_continuation, mq); } /** * Send keepalive message to the neighbour. Must only be called * if we are on 'connected' state or while trying to switch addresses. * Will internally determine if a keepalive is truly needed (so can * always be called). * * @param n neighbour that went idle and needs a keepalive */ static void send_keepalive (struct NeighbourMapEntry *n) { struct SessionKeepAliveMessage m; struct GNUNET_TIME_Relative timeout; uint32_t nonce; GNUNET_assert ((GNUNET_TRANSPORT_PS_CONNECTED == n->state) || (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state)); if (GNUNET_TIME_absolute_get_remaining (n->keep_alive_time).rel_value_us > 0) return; /* no keepalive needed at this time */ nonce = 0; /* 0 indicates 'not set' */ while (0 == nonce) nonce = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending KEEPALIVE to peer `%s' with nonce %u\n", GNUNET_i2s (&n->id), nonce); m.header.size = htons (sizeof (struct SessionKeepAliveMessage)); m.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE); m.nonce = htonl (nonce); timeout = send_with_session (n, &m, sizeof (m), UINT32_MAX /* priority */, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, NULL, NULL); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVES sent"), 1, GNUNET_NO); n->primary_address.keep_alive_nonce = nonce; n->expect_latency_response = GNUNET_YES; n->last_keep_alive_time = GNUNET_TIME_absolute_get (); n->keep_alive_time = GNUNET_TIME_relative_to_absolute (timeout); } /** * Keep the connection to the given neighbour alive longer, * we received a KEEPALIVE (or equivalent); send a response. * * @param neighbour neighbour to keep alive (by sending keep alive response) * @param m the keep alive message containing the nonce to respond to */ void GST_neighbours_keepalive (const struct GNUNET_PeerIdentity *neighbour, const struct GNUNET_MessageHeader *m) { struct NeighbourMapEntry *n; const struct SessionKeepAliveMessage *msg_in; struct SessionKeepAliveMessage msg; if (sizeof (struct SessionKeepAliveMessage) != ntohs (m->size)) { GNUNET_break_op (0); return; } msg_in = (const struct SessionKeepAliveMessage *) m; if (NULL == (n = lookup_neighbour (neighbour))) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE messages discarded (peer unknown)"), 1, GNUNET_NO); return; } if (NULL == n->primary_address.session) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE messages discarded (no session)"), 1, GNUNET_NO); return; } GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received KEEPALIVE request from peer `%s' with nonce %u\n", GNUNET_i2s (&n->id), ntohl (msg_in->nonce)); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVES received in good order"), 1, GNUNET_NO); /* send reply to allow neighbour to measure latency */ msg.header.size = htons (sizeof (struct SessionKeepAliveMessage)); msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE); msg.nonce = msg_in->nonce; (void) send_with_session (n, &msg, sizeof (struct SessionKeepAliveMessage), UINT32_MAX /* priority */, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, NULL, NULL); } /** * We received a KEEP_ALIVE_RESPONSE message and use this to calculate * latency to this peer. Pass the updated information (existing ats * plus calculated latency) to ATS. * * @param neighbour neighbour to keep alive * @param m the message containing the keep alive response */ void GST_neighbours_keepalive_response (const struct GNUNET_PeerIdentity *neighbour, const struct GNUNET_MessageHeader *m) { struct NeighbourMapEntry *n; const struct SessionKeepAliveMessage *msg; struct GNUNET_TRANSPORT_PluginFunctions *papi; struct GNUNET_TIME_Relative latency; if (sizeof (struct SessionKeepAliveMessage) != ntohs (m->size)) { GNUNET_break_op (0); return; } msg = (const struct SessionKeepAliveMessage *) m; if (NULL == (n = lookup_neighbour (neighbour))) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE_RESPONSEs discarded (not connected)"), 1, GNUNET_NO); return; } if ( (GNUNET_TRANSPORT_PS_CONNECTED != n->state) || (GNUNET_YES != n->expect_latency_response) ) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE_RESPONSEs discarded (not expected)"), 1, GNUNET_NO); return; } if (NULL == n->primary_address.address) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE_RESPONSEs discarded (address changed)"), 1, GNUNET_NO); return; } if (n->primary_address.keep_alive_nonce != ntohl (msg->nonce)) { if (0 == n->primary_address.keep_alive_nonce) GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE_RESPONSEs discarded (no nonce)"), 1, GNUNET_NO); else GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE_RESPONSEs discarded (bad nonce)"), 1, GNUNET_NO); return; } GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# KEEPALIVE_RESPONSEs received (OK)"), 1, GNUNET_NO); /* Update session timeout here */ if (NULL != (papi = GST_plugins_find (n->primary_address.address->transport_name))) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Updating session for peer `%s' for session %p\n", GNUNET_i2s (&n->id), n->primary_address.session); papi->update_session_timeout (papi->cls, &n->id, n->primary_address.session); } else { GNUNET_break (0); } n->primary_address.keep_alive_nonce = 0; n->expect_latency_response = GNUNET_NO; set_state_and_timeout (n, n->state, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT)); latency = GNUNET_TIME_absolute_get_duration (n->last_keep_alive_time); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received KEEPALIVE_RESPONSE from peer `%s', latency is %s\n", GNUNET_i2s (&n->id), GNUNET_STRINGS_relative_time_to_string (latency, GNUNET_YES)); GST_ats_update_delay (n->primary_address.address, GNUNET_TIME_relative_divide (latency, 2)); } /** * We have received a message from the given sender. How long should * we delay before receiving more? (Also used to keep the peer marked * as live). * * @param sender sender of the message * @param size size of the message * @param do_forward set to #GNUNET_YES if the message should be forwarded to clients * #GNUNET_NO if the neighbour is not connected or violates the quota, * #GNUNET_SYSERR if the connection is not fully up yet * @return how long to wait before reading more from this sender */ struct GNUNET_TIME_Relative GST_neighbours_calculate_receive_delay (const struct GNUNET_PeerIdentity *sender, ssize_t size, int *do_forward) { struct NeighbourMapEntry *n; struct GNUNET_TIME_Relative ret; if (NULL == neighbours) { *do_forward = GNUNET_NO; return GNUNET_TIME_UNIT_FOREVER_REL; /* This can happen during shutdown */ } if (NULL == (n = lookup_neighbour (sender))) { GST_neighbours_try_connect (sender); if (NULL == (n = lookup_neighbour (sender))) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# messages discarded due to lack of neighbour record"), 1, GNUNET_NO); *do_forward = GNUNET_NO; return GNUNET_TIME_UNIT_ZERO; } } if (! test_connected (n)) { *do_forward = GNUNET_SYSERR; return GNUNET_TIME_UNIT_ZERO; } if (GNUNET_YES == GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, size)) { n->quota_violation_count++; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Bandwidth quota (%u b/s) violation detected (total of %u).\n", n->in_tracker.available_bytes_per_s__, n->quota_violation_count); /* Discount 32k per violation */ GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, -32 * 1024); } else { if (n->quota_violation_count > 0) { /* try to add 32k back */ GNUNET_BANDWIDTH_tracker_consume (&n->in_tracker, 32 * 1024); n->quota_violation_count--; } } if (n->quota_violation_count > QUOTA_VIOLATION_DROP_THRESHOLD) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# bandwidth quota violations by other peers"), 1, GNUNET_NO); *do_forward = GNUNET_NO; return GNUNET_CONSTANTS_QUOTA_VIOLATION_TIMEOUT; } *do_forward = GNUNET_YES; ret = GNUNET_BANDWIDTH_tracker_get_delay (&n->in_tracker, 32 * 1024); if (ret.rel_value_us > 0) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Throttling read (%lld bytes excess at %u b/s), waiting %s before reading more.\n", (long long) n->in_tracker.consumption_since_last_update__, (unsigned int) n->in_tracker.available_bytes_per_s__, GNUNET_STRINGS_relative_time_to_string (ret, GNUNET_YES)); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# ms throttling suggested"), (int64_t) ret.rel_value_us / 1000LL, GNUNET_NO); } return ret; } /** * Transmit a message to the given target using the active connection. * * @param target destination * @param msg message to send * @param msg_size number of bytes in msg * @param timeout when to fail with timeout * @param cont function to call when done * @param cont_cls closure for @a cont */ void GST_neighbours_send (const struct GNUNET_PeerIdentity *target, const void *msg, size_t msg_size, struct GNUNET_TIME_Relative timeout, GST_NeighbourSendContinuation cont, void *cont_cls) { struct NeighbourMapEntry *n; struct MessageQueue *mq; /* All ove these cases should never happen; they are all API violations. But we check anyway, just to be sure. */ if (NULL == (n = lookup_neighbour (target))) { GNUNET_break (0); if (NULL != cont) cont (cont_cls, GNUNET_SYSERR, msg_size, 0); return; } if (GNUNET_YES != test_connected (n)) { GNUNET_break (0); if (NULL != cont) cont (cont_cls, GNUNET_SYSERR, msg_size, 0); return; } bytes_in_send_queue += msg_size; GNUNET_STATISTICS_set (GST_stats, gettext_noop ("# bytes in message queue for other peers"), bytes_in_send_queue, GNUNET_NO); mq = GNUNET_malloc (sizeof (struct MessageQueue) + msg_size); mq->cont = cont; mq->cont_cls = cont_cls; memcpy (&mq[1], msg, msg_size); mq->message_buf = (const char *) &mq[1]; mq->message_buf_size = msg_size; mq->timeout = GNUNET_TIME_relative_to_absolute (timeout); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Enqueueing %u bytes to send to peer %s\n", msg_size, GNUNET_i2s (target)); GNUNET_CONTAINER_DLL_insert_tail (n->messages_head, n->messages_tail, mq); if (NULL != n->task) GNUNET_SCHEDULER_cancel (n->task); n->task = GNUNET_SCHEDULER_add_now (&master_task, n); } /** * Continuation called from our attempt to transmitted our * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN to the specified @a * target. Continue processing based on the @a result. Specifically, * if we failed to transmit, discard the address we used. * * @param cls NULL * @param target which peer received the transmission * @param result #GNUNET_OK if sending worked * @param size_payload how many bytes of payload were sent (ignored) * @param size_on_wire how much bandwidth was consumed on the wire (ignored) */ static void send_session_syn_cont (void *cls, const struct GNUNET_PeerIdentity *target, int result, size_t size_payload, size_t size_on_wire) { struct NeighbourMapEntry *n; n = lookup_neighbour (target); if (NULL == n) { /* SYN continuation was called after neighbor was freed, * for example due to a time out for the state or the session * used was already terminated: nothing to do here... */ return; } if ( (GNUNET_TRANSPORT_PS_SYN_SENT != n->state) && (GNUNET_TRANSPORT_PS_RECONNECT_SENT != n->state) && (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT != n->state)) { /* SYN continuation was called after neighbor changed state, * for example due to a time out for the state or the session * used was already terminated: nothing to do here... */ return; } if (GNUNET_OK == result) return; GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Failed to send SYN message to peer `%s'\n"), GNUNET_i2s (target)); switch (n->state) { case GNUNET_TRANSPORT_PS_SYN_SENT: /* Remove address and request an additional one */ unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: /* Remove address and request an additional one */ unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: /* Remove address and request and go back to primary address */ GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# Failed attempts to switch addresses (failed to send SYN CONT)"), 1, GNUNET_NO); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Switch failed, cleaning up alternative address\n"); free_address (&n->alternative_address); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; default: disconnect_neighbour (n); break; } } /** * Send a SYN message via the given address. * * @param na address to use */ static void send_syn (struct NeighbourAddress *na) { struct GNUNET_TRANSPORT_PluginFunctions *papi; struct TransportSynMessage connect_msg; struct NeighbourMapEntry *n; GNUNET_assert (NULL != na->session); GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Sending SYN message to peer `%s' at %s\n", GNUNET_i2s (&na->address->peer), GST_plugins_a2s (na->address)); papi = GST_plugins_find (na->address->transport_name); GNUNET_assert (NULL != papi); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# SYN messages sent"), 1, GNUNET_NO); na->connect_timestamp = GNUNET_TIME_absolute_get (); connect_msg.header.size = htons (sizeof (struct TransportSynMessage)); connect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN); connect_msg.reserved = htonl (0); connect_msg.timestamp = GNUNET_TIME_absolute_hton (na->connect_timestamp); if (-1 == papi->send (papi->cls, na->session, (const char *) &connect_msg, sizeof (struct TransportSynMessage), UINT_MAX, SETUP_CONNECTION_TIMEOUT, &send_session_syn_cont, NULL)) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Failed to transmit SYN message to %s\n"), GST_plugins_a2s (na->address)); n = lookup_neighbour (&na->address->peer); if (NULL == n) { GNUNET_break (0); return; } switch (n->state) { case GNUNET_TRANSPORT_PS_SYN_SENT: /* Remove address and request and additional one */ GNUNET_assert (na == &n->primary_address); unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT)); /* Hard failure to send the SYN message with this address: Destroy address and session */ break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: /* Remove address and request an additional one */ GNUNET_assert (na == &n->primary_address); unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: GNUNET_assert (na == &n->alternative_address); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# Failed attempts to switch addresses (failed to send SYN)"), 1, GNUNET_NO); /* Remove address and request an additional one */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Switch failed, cleaning up alternative address\n"); free_address (&n->alternative_address); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; default: GNUNET_break (0); disconnect_neighbour (n); break; } return; } GST_neighbours_notify_data_sent (na->address, na->session, sizeof (struct TransportSynMessage)); } /** * Continuation called from our attempt to transmitted our * #GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN_ACK to the specified @a * target. Continue processing based on the @a result. Specifically, * if we failed to transmit, discard the address we used. * * @param cls NULL * @param target which peer received the transmission * @param result #GNUNET_OK if sending worked * @param size_payload how many bytes of payload were sent (ignored) * @param size_on_wire how much bandwidth was consumed on the wire (ignored) */ static void send_session_syn_ack_cont (void *cls, const struct GNUNET_PeerIdentity *target, int result, size_t size_payload, size_t size_on_wire) { struct NeighbourMapEntry *n; n = lookup_neighbour (target); if (NULL == n) { /* SYN_ACK continuation was called after neighbor was freed, * for example due to a time out for the state or the session * used was already terminated: nothing to do here... */ return; } if (GNUNET_TRANSPORT_PS_SYN_RECV_ACK != n->state) { /* SYN_ACK continuation was called after neighbor changed state, * for example due to a time out for the state or the session * used was already terminated: nothing to do here... */ return; } if (GNUNET_OK == result) return; GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Failed to send SYN_ACK message to peer `%s' using address `%s'\n"), GNUNET_i2s (target), GST_plugins_a2s (n->primary_address.address)); /* Remove address and request and additional one */ /* FIXME: what if the neighbour's primary address changed in the meantime? Might want to instead pass "something" around in closure to be sure. */ unset_primary_address (n); n->ack_state = ACK_SEND_SYN_ACK; set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); } /** * Send a SYN_ACK message via the given address. * * @param na address and session to use * @param timestamp timestamp to use for the ACK message * @return #GNUNET_SYSERR if sending immediately failed, #GNUNET_OK otherwise */ static void send_syn_ack_message (struct NeighbourAddress *na, struct GNUNET_TIME_Absolute timestamp) { const struct GNUNET_HELLO_Address *address = na->address; struct Session *session = na->session; struct GNUNET_TRANSPORT_PluginFunctions *papi; struct TransportSynMessage connect_msg; struct NeighbourMapEntry *n; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Sending SYN_ACK to peer `%s'\n", GNUNET_i2s (&address->peer)); if (NULL == (papi = GST_plugins_find (address->transport_name))) { GNUNET_break (0); return; } if (NULL == session) session = papi->get_session (papi->cls, address); if (NULL == session) { GNUNET_break (0); return; } GST_ats_new_session (address, session); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# SYN_ACK messages sent"), 1, GNUNET_NO); connect_msg.header.size = htons (sizeof (struct TransportSynMessage)); connect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_SYN_ACK); connect_msg.reserved = htonl (0); connect_msg.timestamp = GNUNET_TIME_absolute_hton (timestamp); if (GNUNET_SYSERR == papi->send (papi->cls, session, (const char *) &connect_msg, sizeof (struct TransportSynMessage), UINT_MAX, GNUNET_TIME_UNIT_FOREVER_REL, &send_session_syn_ack_cont, NULL)) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Failed to transmit SYN_ACK message to %s\n"), GST_plugins_a2s (address)); n = lookup_neighbour (&address->peer); if (NULL == n) { GNUNET_break (0); return; } /* Remove address and request and additional one */ unset_primary_address (n); n->ack_state = ACK_SEND_SYN_ACK; set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); return; } } /** * Function called by the bandwidth tracker for a peer whenever * the tracker's state changed such that we need to recalculate * the delay for flow control. We calculate the latest delay * and inform the plugin (if applicable). * * @param cls the `struct NeighbourMapEntry` to update calculations for */ static void inbound_bw_tracker_update (void *cls) { struct NeighbourMapEntry *n = cls; struct GNUNET_TRANSPORT_PluginFunctions *papi; struct GNUNET_TIME_Relative delay; int do_forward; if (NULL == n->primary_address.address) return; /* not active, ignore */ papi = GST_plugins_find (n->primary_address.address->transport_name); GNUNET_assert (NULL != papi); if (NULL == papi->update_inbound_delay) return; delay = GST_neighbours_calculate_receive_delay (&n->id, 0, &do_forward); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "New inbound delay for peer `%s' is %llu ms\n", GNUNET_i2s (&n->id), delay.rel_value_us / 1000); papi->update_inbound_delay (papi->cls, &n->id, n->primary_address.session, delay); } /** * Create a fresh entry in the neighbour map for the given peer * * @param peer peer to create an entry for * @return new neighbour map entry */ static struct NeighbourMapEntry * setup_neighbour (const struct GNUNET_PeerIdentity *peer) { struct NeighbourMapEntry *n; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Creating new neighbour entry for `%s'\n", GNUNET_i2s (peer)); n = GNUNET_new (struct NeighbourMapEntry); n->id = *peer; n->ack_state = ACK_UNDEFINED; n->last_util_transmission = GNUNET_TIME_absolute_get(); n->neighbour_receive_quota = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT; GNUNET_BANDWIDTH_tracker_init (&n->in_tracker, &inbound_bw_tracker_update, n, GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT, MAX_BANDWIDTH_CARRY_S); n->task = GNUNET_SCHEDULER_add_now (&master_task, n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_NOT_CONNECTED, GNUNET_TIME_UNIT_FOREVER_ABS); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multipeermap_put (neighbours, &n->id, n, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); n->suggest_handle = GNUNET_ATS_connectivity_suggest (GST_ats_connect, peer); return n; } /** * Entry in a DLL we use to keep track of pending blacklist checks. */ struct BlacklistCheckSwitchContext { /** * DLL prev pointer. */ struct BlacklistCheckSwitchContext *prev; /** * DLL next pointer. */ struct BlacklistCheckSwitchContext *next; /** * Handle to the blacklist check we are performing. */ struct GST_BlacklistCheck *blc; /** * Inbound bandwidth that was assigned to @e address. */ struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in; /** * Outbound bandwidth that was assigned to @e address. */ struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out; }; /** * Black list check result for try_connect call * If connection to the peer is allowed request adddress and * * @param cls blc_ctx bl context * @param peer the peer * @param address address associated with the request * @param session session associated with the request * @param result #GNUNET_OK if the connection is allowed, * #GNUNET_NO if not, * #GNUNET_SYSERR if operation was aborted */ static void try_connect_bl_check_cont (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_HELLO_Address *address, struct Session *session, int result) { struct BlacklistCheckSwitchContext *blc_ctx = cls; struct NeighbourMapEntry *n; GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, blc_ctx); GNUNET_free (blc_ctx); if (GNUNET_OK != result) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Blacklisting disapproved to connect to peer `%s'\n"), GNUNET_i2s (peer)); return; } /* Setup a new neighbour */ if (NULL != lookup_neighbour(peer)) return; /* The neighbor was created in the meantime while waited for BL clients */ n = setup_neighbour (peer); /* Request address suggestions for this peer */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); } /** * Try to create a connection to the given target (eventually). * * @param target peer to try to connect to */ void GST_neighbours_try_connect (const struct GNUNET_PeerIdentity *target) { struct NeighbourMapEntry *n; struct GST_BlacklistCheck *blc; struct BlacklistCheckSwitchContext *blc_ctx; if (NULL == neighbours) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Asked to connect to peer `%s' during shutdown\n", GNUNET_i2s (target)); return; /* during shutdown, do nothing */ } n = lookup_neighbour (target); GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Asked to connect to peer `%s' (state: %s)\n", GNUNET_i2s (target), (NULL != n) ? GNUNET_TRANSPORT_ps2s(n->state) : "NEW PEER"); if (NULL != n) { switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: /* this should not be possible */ GNUNET_break (0); free_neighbour (n); break; case GNUNET_TRANSPORT_PS_INIT_ATS: case GNUNET_TRANSPORT_PS_SYN_SENT: case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Ignoring request to try to connect to `%s', already trying!\n", GNUNET_i2s (target)); return; /* already trying */ case GNUNET_TRANSPORT_PS_CONNECTED: case GNUNET_TRANSPORT_PS_RECONNECT_ATS: case GNUNET_TRANSPORT_PS_RECONNECT_SENT: case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Ignoring request to try to connect, already connected to `%s'!\n", GNUNET_i2s (target)); return; /* already connected */ case GNUNET_TRANSPORT_PS_DISCONNECT: /* get rid of remains, ready to re-try immediately */ free_neighbour (n); break; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: /* should not be possible */ GNUNET_assert (0); return; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); free_neighbour (n); break; } } /* Do blacklist check if connecting to this peer is allowed */ blc_ctx = GNUNET_new (struct BlacklistCheckSwitchContext); GNUNET_CONTAINER_DLL_insert (pending_bc_head, pending_bc_tail, blc_ctx); if (NULL != (blc = GST_blacklist_test_allowed (target, NULL, &try_connect_bl_check_cont, blc_ctx, NULL, NULL))) { blc_ctx->blc = blc; } } /** * We received a 'SYN' message from the other peer. * Consider switching to it. * * @param message possibly a `struct TransportSynMessage` (check format) * @param peer identity of the peer to switch the address for * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error */ int GST_neighbours_handle_session_syn (const struct GNUNET_MessageHeader *message, const struct GNUNET_PeerIdentity *peer) { const struct TransportSynMessage *scm; struct NeighbourMapEntry *n; struct GNUNET_TIME_Absolute ts; if (ntohs (message->size) != sizeof (struct TransportSynMessage)) { GNUNET_break_op (0); return GNUNET_SYSERR; } GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# SYN messages received"), 1, GNUNET_NO); if (NULL == neighbours) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("SYN request from peer `%s' ignored due impending shutdown\n"), GNUNET_i2s (peer)); return GNUNET_OK; /* we're shutting down */ } scm = (const struct TransportSynMessage *) message; GNUNET_break_op (0 == ntohl (scm->reserved)); ts = GNUNET_TIME_absolute_ntoh (scm->timestamp); n = lookup_neighbour (peer); if (NULL == n) { /* This is a new neighbour and set to not connected */ n = setup_neighbour (peer); } /* Remember this SYN message in neighbour */ n->ack_state = ACK_SEND_SYN_ACK; n->connect_ack_timestamp = ts; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Received SYN for peer `%s' in state %s/%s\n", GNUNET_i2s (peer), GNUNET_TRANSPORT_ps2s (n->state), print_ack_state (n->ack_state)); switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: /* Request an address from ATS to send SYN_ACK to this peer */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_INIT_ATS: /* SYN message takes priority over us asking ATS for address: * Wait for ATS to suggest an address and send SYN_ACK */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: /* We already wait for an address to send an SYN_ACK */ break; case GNUNET_TRANSPORT_PS_SYN_SENT: case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: /* Send ACK immediately */ n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, ts); break; case GNUNET_TRANSPORT_PS_CONNECTED: /* we are already connected and can thus send the ACK immediately */ GNUNET_assert (NULL != n->primary_address.address); GNUNET_assert (NULL != n->primary_address.session); n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, ts); break; case GNUNET_TRANSPORT_PS_RECONNECT_ATS: /* We wait for ATS address suggestion */ break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: /* We received a SYN message while waiting for a SYN_ACK in fast * reconnect. Send SYN_ACK immediately */ n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, n->connect_ack_timestamp); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: /* We are already connected and can thus send the ACK immediately; still, it can never hurt to have an alternative address, so also tell ATS about it */ GNUNET_assert (NULL != n->primary_address.address); GNUNET_assert (NULL != n->primary_address.session); n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, ts); break; case GNUNET_TRANSPORT_PS_DISCONNECT: /* Get rid of remains and re-try */ free_neighbour (n); n = setup_neighbour (peer); /* Remember the SYN time stamp for ACK message */ n->ack_state = ACK_SEND_SYN_ACK; n->connect_ack_timestamp = ts; /* Request an address for the peer */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: /* should not be possible */ GNUNET_assert (0); break; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Check if the given @a address is the same that we are already * using for the respective neighbour. If so, update the bandwidth * assignment and possibly the session and return #GNUNET_OK. * If the new address is different from what the neighbour is * using right now, return #GNUNET_NO. * * @param address address of the other peer, * @param session session to use or NULL if transport should initiate a session * @param bandwidth_in inbound quota to be used when connection is up, * 0 to disconnect from peer * @param bandwidth_out outbound quota to be used when connection is up, * 0 to disconnect from peer * @return #GNUNET_OK if we were able to just update the bandwidth and session, * #GNUNET_NO if more extensive changes are required (address changed) */ static int try_run_fast_ats_update (const struct GNUNET_HELLO_Address *address, struct Session *session, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out) { struct NeighbourMapEntry *n; struct GNUNET_BANDWIDTH_Value32NBO bandwidth_min; n = lookup_neighbour (&address->peer); if ( (NULL == n) || (NULL == n->primary_address.address) || (0 != GNUNET_HELLO_address_cmp (address, n->primary_address.address)) ) return GNUNET_NO; /* We are not really switching addresses, but merely adjusting session and/or bandwidth, can do fast ATS update! */ if (session != n->primary_address.session) { /* switch to a different session, but keeping same address; could happen if there is a 2nd inbound connection */ n->primary_address.session = session; GNUNET_assert (GNUNET_YES == GST_ats_is_known (n->primary_address.address, n->primary_address.session)); } if (n->primary_address.bandwidth_in.value__ != bandwidth_in.value__) { n->primary_address.bandwidth_in = bandwidth_in; GST_neighbours_set_incoming_quota (&address->peer, bandwidth_in); } if (n->primary_address.bandwidth_out.value__ != bandwidth_out.value__) { n->primary_address.bandwidth_out = bandwidth_out; bandwidth_min = GNUNET_BANDWIDTH_value_min (bandwidth_out, n->neighbour_receive_quota); send_outbound_quota_to_clients (&address->peer, bandwidth_min); } return GNUNET_OK; } /** * We've been asked to switch addresses, and just now got the result * from the blacklist check to see if this is allowed. * * @param cls the `struct BlacklistCheckSwitchContext` with * the information about the future address * @param peer the peer we may switch addresses on * @param address address associated with the request * @param session session associated with the request * @param result #GNUNET_OK if the connection is allowed, * #GNUNET_NO if not, * #GNUNET_SYSERR if operation was aborted */ static void switch_address_bl_check_cont (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_HELLO_Address *address, struct Session *session, int result) { struct BlacklistCheckSwitchContext *blc_ctx = cls; struct GNUNET_TRANSPORT_PluginFunctions *papi; struct NeighbourMapEntry *n; if (GNUNET_SYSERR == result) goto cleanup; papi = GST_plugins_find (address->transport_name); GNUNET_assert (NULL != papi); if (GNUNET_NO == result) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Blacklist denied to switch to suggested address `%s' session %p for peer `%s'\n", GST_plugins_a2s (address), session, GNUNET_i2s (peer)); GNUNET_STATISTICS_update (GST_stats, "# ATS suggestions ignored (blacklist denied)", 1, GNUNET_NO); papi->disconnect_session (papi->cls, session); if (GNUNET_YES != GNUNET_HELLO_address_check_option (address, GNUNET_HELLO_ADDRESS_INFO_INBOUND)) GST_ats_block_address (address, NULL); goto cleanup; } if (NULL == session) { /* need to create a session, ATS only gave us an address */ session = papi->get_session (papi->cls, address); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Obtained new session for peer `%s' and address '%s': %p\n", GNUNET_i2s (&address->peer), GST_plugins_a2s (address), session); if (NULL != session) GST_ats_new_session (address, session); } if (NULL == session) { /* session creation failed, bad!, fail! */ GNUNET_STATISTICS_update (GST_stats, "# ATS suggestions ignored (failed to create session)", 1, GNUNET_NO); /* No session could be obtained, remove blacklist check and clean up */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Failed to obtain new session for peer `%s' and address '%s'\n", GNUNET_i2s (&address->peer), GST_plugins_a2s (address)); GST_ats_block_address (address, session); goto cleanup; } /* We did this check already before going into blacklist, but it is theoretically possible that the situation changed in the meantime, hence we check again here */ if (GNUNET_OK == try_run_fast_ats_update (address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out)) goto cleanup; /* was just a minor update, we're done */ /* check if we also need to setup the neighbour entry */ if (NULL == (n = lookup_neighbour (peer))) { n = setup_neighbour (peer); n->state = GNUNET_TRANSPORT_PS_INIT_ATS; } GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Peer `%s' switches to address `%s'\n", GNUNET_i2s (&address->peer), GST_plugins_a2s (address)); switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: GNUNET_break (0); GST_ats_block_address (address, session); free_neighbour (n); return; case GNUNET_TRANSPORT_PS_INIT_ATS: /* We requested an address and ATS suggests one: * set primary address and send SYN message*/ set_primary_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); if (ACK_SEND_SYN_ACK == n->ack_state) { /* Send pending SYN_ACK message */ n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, n->connect_ack_timestamp); } set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_SENT, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); send_syn (&n->primary_address); break; case GNUNET_TRANSPORT_PS_SYN_SENT: /* ATS suggested a new address while waiting for an SYN_ACK: * Switch and send new SYN */ /* ATS suggests a different address, switch again */ set_primary_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); if (ACK_SEND_SYN_ACK == n->ack_state) { /* Send pending SYN_ACK message */ n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, n->connect_ack_timestamp); } set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_SENT, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); send_syn (&n->primary_address); break; case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: /* We requested an address and ATS suggests one: * set primary address and send SYN_ACK message*/ set_primary_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); /* Send an ACK message as a response to the SYN msg */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ACK, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); send_syn_ack_message (&n->primary_address, n->connect_ack_timestamp); if ( (ACK_SEND_SYN_ACK == n->ack_state) || (ACK_UNDEFINED == n->ack_state) ) n->ack_state = ACK_SEND_ACK; break; case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: /* ATS asks us to switch while we were trying to connect; switch to new address and check blacklist again */ if ( (ACK_SEND_SYN_ACK == n->ack_state) ) { n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, n->connect_ack_timestamp); } set_primary_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SYN_RECV_ACK, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_CONNECTED: GNUNET_assert (NULL != n->primary_address.address); GNUNET_assert (NULL != n->primary_address.session); GNUNET_break (n->primary_address.session != session); /* ATS asks us to switch a life connection; see if we can get a SYN_ACK on it before we actually do this! */ set_alternative_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# Attempts to switch addresses"), 1, GNUNET_NO); send_syn (&n->alternative_address); break; case GNUNET_TRANSPORT_PS_RECONNECT_ATS: set_primary_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); if (ACK_SEND_SYN_ACK == n->ack_state) { /* Send pending SYN_ACK message */ n->ack_state = ACK_SEND_ACK; send_syn_ack_message (&n->primary_address, n->connect_ack_timestamp); } set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_SENT, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT)); send_syn (&n->primary_address); break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: /* ATS asks us to switch while we were trying to reconnect; switch to new address and send SYN again */ set_primary_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_SENT, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT)); send_syn (&n->primary_address); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: if ( (0 == GNUNET_HELLO_address_cmp (n->primary_address.address, address)) && (n->primary_address.session == session) ) { /* ATS switches back to still-active session */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "ATS double-switched, cleaning up alternative address\n"); free_address (&n->alternative_address); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, n->timeout); break; } /* ATS asks us to switch a life connection, send */ set_alternative_address (n, address, session, blc_ctx->bandwidth_in, blc_ctx->bandwidth_out); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); send_syn (&n->alternative_address); break; case GNUNET_TRANSPORT_PS_DISCONNECT: /* not going to switch addresses while disconnecting */ GNUNET_STATISTICS_update (GST_stats, "# ATS suggestion ignored (disconnecting)", 1, GNUNET_NO); return; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: GNUNET_assert (0); break; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); break; } cleanup: GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, blc_ctx); GNUNET_free (blc_ctx); } /** * For the given peer, switch to this address. * * Before accepting this addresses and actively using it, a blacklist check * is performed. * * If any check fails or the suggestion can somehow not be followed, we * MUST call #GST_ats_block_address() to tell ATS that the suggestion * could not be satisfied and force ATS to do something else. * * @param address address of the other peer, * @param session session to use or NULL if transport should initiate a session * @param bandwidth_in inbound quota to be used when connection is up, * 0 to disconnect from peer * @param bandwidth_out outbound quota to be used when connection is up, * 0 to disconnect from peer */ void GST_neighbours_switch_to_address (const struct GNUNET_HELLO_Address *address, struct Session *session, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in, struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out) { struct GST_BlacklistCheck *blc; struct BlacklistCheckSwitchContext *blc_ctx; GNUNET_assert (NULL != address->transport_name); if (GNUNET_OK == try_run_fast_ats_update (address, session, bandwidth_in, bandwidth_out)) return; /* Check if plugin is available */ if (NULL == (GST_plugins_find (address->transport_name))) { /* we don't have the plugin for this address */ GNUNET_break (0); GST_ats_block_address (address, session); return; } if ((NULL == session) && (GNUNET_HELLO_address_check_option (address, GNUNET_HELLO_ADDRESS_INFO_INBOUND))) { /* This is a inbound address and we do not have a session to use! */ GNUNET_break (0); GST_ats_block_address (address, session); return; } GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "ATS suggests address '%s' for peer `%s' at %u/%u speed\n", GST_plugins_a2s (address), GNUNET_i2s (&address->peer), (unsigned int) ntohl (bandwidth_in.value__), (unsigned int) ntohl (bandwidth_out.value__)); /* Perform blacklist check */ blc_ctx = GNUNET_new (struct BlacklistCheckSwitchContext); blc_ctx->bandwidth_in = bandwidth_in; blc_ctx->bandwidth_out = bandwidth_out; GNUNET_CONTAINER_DLL_insert (pending_bc_head, pending_bc_tail, blc_ctx); if (NULL != (blc = GST_blacklist_test_allowed (&address->peer, address->transport_name, &switch_address_bl_check_cont, blc_ctx, address, session))) { blc_ctx->blc = blc; } } /** * Function called to send network utilization data to ATS for * each active connection. * * @param cls NULL * @param key peer we send utilization data for * @param value the `struct NeighbourMapEntry *` with data to send * @return #GNUNET_OK (continue to iterate) */ static int send_utilization_data (void *cls, const struct GNUNET_PeerIdentity *key, void *value) { struct NeighbourMapEntry *n = value; uint32_t bps_in; uint32_t bps_out; struct GNUNET_TIME_Relative delta; if ( (GNUNET_YES != test_connected (n)) || (NULL == n->primary_address.address) ) return GNUNET_OK; delta = GNUNET_TIME_absolute_get_difference (n->last_util_transmission, GNUNET_TIME_absolute_get ()); bps_in = 0; if ((0 != n->util_total_bytes_recv) && (0 != delta.rel_value_us)) bps_in = (1000LL * 1000LL * n->util_total_bytes_recv) / (delta.rel_value_us); bps_out = 0; if ((0 != n->util_total_bytes_sent) && (0 != delta.rel_value_us)) bps_out = (1000LL * 1000LL * n->util_total_bytes_sent) / delta.rel_value_us; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s' total: received %u Bytes/s, sent %u Bytes/s\n", GNUNET_i2s (key), bps_in, bps_out); GST_ats_update_utilization (n->primary_address.address, bps_in, bps_out); n->util_total_bytes_recv = 0; n->util_total_bytes_sent = 0; n->last_util_transmission = GNUNET_TIME_absolute_get (); return GNUNET_OK; } /** * Task transmitting utilization in a regular interval * * @param cls the 'struct NeighbourMapEntry' for which we are running * @param tc scheduler context (unused) */ static void utilization_transmission (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { util_transmission_tk = NULL; GNUNET_CONTAINER_multipeermap_iterate (neighbours, &send_utilization_data, NULL); util_transmission_tk = GNUNET_SCHEDULER_add_delayed (UTIL_TRANSMISSION_INTERVAL, &utilization_transmission, NULL); } /** * Track information about data we received from the * given address (used to notify ATS about our utilization * of allocated resources). * * @param address the address we got data from * @param message the message we received (really only the size is used) */ void GST_neighbours_notify_data_recv (const struct GNUNET_HELLO_Address *address, const struct GNUNET_MessageHeader *message) { struct NeighbourMapEntry *n; n = lookup_neighbour (&address->peer); if (NULL == n) return; n->util_total_bytes_recv += ntohs (message->size); } /** * Track information about data we transmitted using the given @a * address and @a session (used to notify ATS about our utilization of * allocated resources). * * @param address the address we transmitted data to * @param session session we used to transmit data * @param message the message we sent (really only the size is used) */ void GST_neighbours_notify_data_sent (const struct GNUNET_HELLO_Address *address, struct Session *session, size_t size) { struct NeighbourMapEntry *n; n = lookup_neighbour (&address->peer); if (NULL == n) return; if (n->primary_address.session != session) return; n->util_total_bytes_sent += size; } /** * Master task run for every neighbour. Performs all of the time-related * activities (keep alive, send next message, disconnect if idle, finish * clean up after disconnect). * * @param cls the 'struct NeighbourMapEntry' for which we are running * @param tc scheduler context (unused) */ static void master_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct NeighbourMapEntry *n = cls; struct GNUNET_TIME_Relative delay; n->task = NULL; delay = GNUNET_TIME_absolute_get_remaining (n->timeout); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Master task runs for neighbour `%s' in state %s with timeout in %s\n", GNUNET_i2s (&n->id), GNUNET_TRANSPORT_ps2s(n->state), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES)); switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: /* invalid state for master task, clean up */ GNUNET_break (0); free_neighbour (n); return; case GNUNET_TRANSPORT_PS_INIT_ATS: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out waiting for ATS to provide address\n", GNUNET_i2s (&n->id)); free_neighbour (n); return; } break; case GNUNET_TRANSPORT_PS_SYN_SENT: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out waiting for other peer to send SYN_ACK\n", GNUNET_i2s (&n->id)); /* Remove address and request and additional one */ unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); return; } break; case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out waiting ATS to provide address to use for SYN_ACK\n", GNUNET_i2s (&n->id)); free_neighbour (n); return; } break; case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out waiting for other peer to send ACK\n", GNUNET_i2s (&n->id)); disconnect_neighbour (n); return; } break; case GNUNET_TRANSPORT_PS_CONNECTED: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out, missing KEEPALIVE_RESPONSEs\n", GNUNET_i2s (&n->id)); disconnect_neighbour (n); return; } try_transmission_to_peer (n); send_keepalive (n); break; case GNUNET_TRANSPORT_PS_RECONNECT_ATS: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out, waiting for ATS replacement address\n", GNUNET_i2s (&n->id)); disconnect_neighbour (n); return; } break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Connection to `%s' timed out, waiting for other peer to SYN_ACK replacement address\n", GNUNET_i2s (&n->id)); disconnect_neighbour (n); return; } break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: if (0 == delay.rel_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Switch failed, cleaning up alternative address\n"); free_address (&n->alternative_address); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (SETUP_CONNECTION_TIMEOUT)); } try_transmission_to_peer (n); send_keepalive (n); break; case GNUNET_TRANSPORT_PS_DISCONNECT: GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Cleaning up connection to `%s' after sending DISCONNECT\n", GNUNET_i2s (&n->id)); free_neighbour (n); return; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: /* how did we get here!? */ GNUNET_assert (0); break; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); break; } delay = GNUNET_TIME_absolute_get_remaining (n->timeout); if ( (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state) || (GNUNET_TRANSPORT_PS_CONNECTED == n->state) ) { /* if we are *now* in one of the two states, we're sending keep alive messages, so we need to consider the keepalive delay, not just the connection timeout */ delay = GNUNET_TIME_relative_min (GNUNET_TIME_absolute_get_remaining (n->keep_alive_time), delay); } if (NULL == n->task) n->task = GNUNET_SCHEDULER_add_delayed (delay, &master_task, n); } /** * Send a ACK message to the neighbour to confirm that we * got his SYN_ACK. * * @param n neighbour to send the ACK to */ static void send_session_ack_message (struct NeighbourMapEntry *n) { struct GNUNET_MessageHeader msg; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Sending ACK message to peer `%s'\n", GNUNET_i2s (&n->id)); msg.size = htons (sizeof (struct GNUNET_MessageHeader)); msg.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_ACK); (void) send_with_session (n, &msg, sizeof (struct GNUNET_MessageHeader), UINT32_MAX, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_NO, NULL, NULL); } /** * We received a 'SESSION_SYN_ACK' message from the other peer. * Consider switching to it. * * @param message possibly a `struct SessionConnectMessage` (check format) * @param peer identity of the peer to switch the address for * @param address address of the other peer, NULL if other peer * connected to us * @param session session to use (or NULL) * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error */ int GST_neighbours_handle_session_syn_ack (const struct GNUNET_MessageHeader *message, const struct GNUNET_HELLO_Address *address, struct Session *session) { const struct TransportSynMessage *scm; struct GNUNET_TIME_Absolute ts; struct NeighbourMapEntry *n; if (ntohs (message->size) != sizeof (struct TransportSynMessage)) { GNUNET_break_op (0); return GNUNET_SYSERR; } GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# SYN_ACK messages received"), 1, GNUNET_NO); scm = (const struct TransportSynMessage *) message; GNUNET_break_op (ntohl (scm->reserved) == 0); if (NULL == (n = lookup_neighbour (&address->peer))) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# unexpected SYN_ACK messages (no peer)"), 1, GNUNET_NO); return GNUNET_SYSERR; } GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received SYN_ACK message from peer `%s' in state %s/%s\n", GNUNET_i2s (&address->peer), GNUNET_TRANSPORT_ps2s (n->state), print_ack_state (n->ack_state)); ts = GNUNET_TIME_absolute_ntoh (scm->timestamp); switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: GNUNET_break (0); free_neighbour (n); return GNUNET_SYSERR; case GNUNET_TRANSPORT_PS_INIT_ATS: GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# unexpected SYN_ACK messages (not ready)"), 1, GNUNET_NO); break; case GNUNET_TRANSPORT_PS_SYN_SENT: if (ts.abs_value_us != n->primary_address.connect_timestamp.abs_value_us) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, "SYN_ACK ignored as the timestamp does not match our SYN request\n"); return GNUNET_OK; } set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT)); set_primary_address (n, n->primary_address.address, n->primary_address.session, n->primary_address.bandwidth_in, n->primary_address.bandwidth_out); send_session_ack_message (n); break; case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# unexpected SYN_ACK messages (not ready)"), 1, GNUNET_NO); break; case GNUNET_TRANSPORT_PS_CONNECTED: /* duplicate SYN_ACK, let's answer by duplicate ACK just in case */ send_session_ack_message (n); break; case GNUNET_TRANSPORT_PS_RECONNECT_ATS: /* we didn't expect any SYN_ACK, as we are waiting for ATS to give us a new address... */ GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# unexpected SYN_ACK messages (waiting on ATS)"), 1, GNUNET_NO); break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: /* Reconnecting with new address address worked; go back to connected! */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT)); send_session_ack_message (n); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: /* new address worked; adopt it and go back to connected! */ set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT)); GNUNET_break (GNUNET_NO == n->alternative_address.ats_active); /* Set primary addresses */ set_primary_address (n, n->alternative_address.address, n->alternative_address.session, n->alternative_address.bandwidth_in, n->alternative_address.bandwidth_out); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# Successful attempts to switch addresses"), 1, GNUNET_NO); GNUNET_HELLO_address_free (n->alternative_address.address); memset (&n->alternative_address, 0, sizeof (n->alternative_address)); send_session_ack_message (n); break; case GNUNET_TRANSPORT_PS_DISCONNECT: GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# unexpected SYN_ACK messages (disconnecting)"), 1, GNUNET_NO); return GNUNET_SYSERR; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: GNUNET_assert (0); break; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * A session was terminated. Take note; if needed, try to get * an alternative address from ATS. * * @param peer identity of the peer where the session died * @param session session that is gone * @return #GNUNET_YES if this was a session used, #GNUNET_NO if * this session was not in use */ int GST_neighbours_session_terminated (const struct GNUNET_PeerIdentity *peer, struct Session *session) { struct NeighbourMapEntry *n; struct BlackListCheckContext *bcc; struct BlackListCheckContext *bcc_next; /* make sure to cancel all ongoing blacklist checks involving 'session' */ bcc_next = bc_head; while (NULL != (bcc = bcc_next)) { bcc_next = bcc->next; if (bcc->na.session == session) { if (NULL != bcc->bc) GST_blacklist_test_cancel (bcc->bc); GNUNET_HELLO_address_free (bcc->na.address); GNUNET_CONTAINER_DLL_remove (bc_head, bc_tail, bcc); GNUNET_free (bcc); } } if (NULL == (n = lookup_neighbour (peer))) return GNUNET_NO; /* can't affect us */ if (session != n->primary_address.session) { /* Free alternative address */ if (session == n->alternative_address.session) { if (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state) set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, n->timeout); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Session died, cleaning up alternative address\n"); free_address (&n->alternative_address); } return GNUNET_NO; /* doesn't affect us further */ } n->expect_latency_response = GNUNET_NO; /* The session for neighbour's primary address died */ switch (n->state) { case GNUNET_TRANSPORT_PS_NOT_CONNECTED: GNUNET_break (0); free_neighbour (n); return GNUNET_YES; case GNUNET_TRANSPORT_PS_INIT_ATS: GNUNET_break (0); free_neighbour (n); return GNUNET_YES; case GNUNET_TRANSPORT_PS_SYN_SENT: /* The session used to send the SYN terminated: * this implies a connect error*/ GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Failed to send SYN in %s with `%s' %p: session terminated\n", "CONNECT_SENT", GST_plugins_a2s (n->primary_address.address), n->primary_address.session, GNUNET_i2s (peer)); /* Destroy the address since it cannot be used */ unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_INIT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_SYN_RECV_ATS: case GNUNET_TRANSPORT_PS_SYN_RECV_ACK: /* error on inbound session; free neighbour entirely */ free_neighbour (n); return GNUNET_YES; case GNUNET_TRANSPORT_PS_CONNECTED: /* Our primary connection died, try a fast reconnect */ unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_RECONNECT_ATS: /* we don't have an address, how can it go down? */ GNUNET_break (0); break; case GNUNET_TRANSPORT_PS_RECONNECT_SENT: GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Failed to send SYN in %s with `%s' %p: session terminated\n", "RECONNECT_SENT", GST_plugins_a2s (n->primary_address.address), n->primary_address.session, GNUNET_i2s (peer)); /* Destroy the address since it cannot be used */ unset_primary_address (n); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_ATS, GNUNET_TIME_relative_to_absolute (ATS_RESPONSE_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT: /* primary went down while we were waiting for SYN_ACK on secondary; secondary as primary */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connection `%s' %p to peer `%s' was terminated while switching, " "switching to alternative address `%s' %p\n", GST_plugins_a2s (n->primary_address.address), n->primary_address.session, GNUNET_i2s (peer), GST_plugins_a2s (n->alternative_address.address), n->alternative_address.session); /* Destroy the inbound address since it cannot be used */ free_address (&n->primary_address); n->primary_address = n->alternative_address; GNUNET_assert (GNUNET_YES == GST_ats_is_known (n->primary_address.address, n->primary_address.session)); memset (&n->alternative_address, 0, sizeof (struct NeighbourAddress)); set_state_and_timeout (n, GNUNET_TRANSPORT_PS_RECONNECT_SENT, GNUNET_TIME_relative_to_absolute (FAST_RECONNECT_TIMEOUT)); break; case GNUNET_TRANSPORT_PS_DISCONNECT: unset_primary_address (n); break; case GNUNET_TRANSPORT_PS_DISCONNECT_FINISHED: /* neighbour was freed and plugins told to terminate session */ return GNUNET_NO; default: GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Unhandled state `%s'\n", GNUNET_TRANSPORT_ps2s (n->state)); GNUNET_break (0); break; } if (NULL != n->task) GNUNET_SCHEDULER_cancel (n->task); n->task = GNUNET_SCHEDULER_add_now (&master_task, n); return GNUNET_YES; } /** * We received a 'ACK' message from the other peer. * If we sent a 'SYN_ACK' last, this means we are now * connected. Otherwise, do nothing. * * @param message possibly a 'struct SessionConnectMessage' (check format) * @param address address of the other peer * @param session session to use (or NULL) * @return #GNUNET_OK if the message was fine, #GNUNET_SYSERR on serious error */ int GST_neighbours_handle_session_ack (const struct GNUNET_MessageHeader *message, const struct GNUNET_HELLO_Address *address, struct Session *session) { struct NeighbourMapEntry *n; if (ntohs (message->size) != sizeof (struct GNUNET_MessageHeader)) { GNUNET_break_op (0); return GNUNET_SYSERR; } GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# ACK messages received"), 1, GNUNET_NO); if (NULL == (n = lookup_neighbour (&address->peer))) { GNUNET_break_op (0); return GNUNET_SYSERR; } GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received ACK for peer `%s' in state %s/%s\n", GNUNET_i2s (&address->peer), GNUNET_TRANSPORT_ps2s (n->state), print_ack_state (n->ack_state)); /* Check if we are in a plausible state for having sent a SYN_ACK. If not, return, otherwise break. The remote peers sends a ACK as a response for a SYN_ACK message. We expect a ACK: - If a remote peer has sent a SYN, we responded with a SYN_ACK and now wait for the ACK to finally be connected - If we sent a SYN_ACK to this peer before */ if ( (GNUNET_TRANSPORT_PS_SYN_RECV_ACK != n->state) && (ACK_SEND_ACK != n->ack_state)) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Received unexpected ACK message from peer `%s' in state %s/%s\n", GNUNET_i2s (&address->peer), GNUNET_TRANSPORT_ps2s (n->state), print_ack_state (n->ack_state)); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# unexpected ACK messages"), 1, GNUNET_NO); return GNUNET_OK; } if (GNUNET_TRANSPORT_PS_SWITCH_SYN_SENT == n->state) { /* We tried to switch addresses while being connect. We explicitly wait * for a SYN_ACK before going to GNUNET_TRANSPORT_PS_CONNECTED, * so we do not want to set the address as in use! */ return GNUNET_OK; } set_state_and_timeout (n, GNUNET_TRANSPORT_PS_CONNECTED, GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT)); /* Reset backoff for primary address */ GST_ats_block_reset (n->primary_address.address, n->primary_address.session); return GNUNET_OK; } /** * Test if we're connected to the given peer. * * @param target peer to test * @return #GNUNET_YES if we are connected, #GNUNET_NO if not */ int GST_neighbours_test_connected (const struct GNUNET_PeerIdentity *target) { return test_connected (lookup_neighbour (target)); } /** * Change the incoming quota for the given peer. Updates * our own receive rate and informs the neighbour about * the new quota. * * @param neighbour identity of peer to change qutoa for * @param quota new quota */ void GST_neighbours_set_incoming_quota (const struct GNUNET_PeerIdentity *neighbour, struct GNUNET_BANDWIDTH_Value32NBO quota) { struct NeighbourMapEntry *n; if (NULL == (n = lookup_neighbour (neighbour))) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# SET QUOTA messages ignored (no such peer)"), 1, GNUNET_NO); return; } GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Setting inbound quota of %u Bps for peer `%s' to all clients\n", ntohl (quota.value__), GNUNET_i2s (&n->id)); GNUNET_BANDWIDTH_tracker_update_quota (&n->in_tracker, quota); if (0 != ntohl (quota.value__)) { struct SessionQuotaMessage sqm; sqm.header.size = htons (sizeof (struct SessionQuotaMessage)); sqm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_QUOTA); sqm.quota = quota.value__; (void) send_with_session (n, &sqm, sizeof (sqm), UINT32_MAX - 1, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_NO, NULL, NULL); return; } GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Disconnecting peer `%4s' due to SET_QUOTA\n", GNUNET_i2s (&n->id)); if (GNUNET_YES == test_connected (n)) GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# disconnects due to quota of 0"), 1, GNUNET_NO); disconnect_neighbour (n); } /** * Task to asynchronously run #free_neighbour(). * * @param cls the `struct NeighbourMapEntry` to free * @param tc unused */ static void delayed_disconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext* tc) { struct NeighbourMapEntry *n = cls; n->delayed_disconnect_task = NULL; GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Disconnecting by request from peer %s\n", GNUNET_i2s (&n->id)); free_neighbour (n); } /** * We received a quoat message from the given peer, * validate and process. * * @param peer sender of the message * @param msg the quota message */ void GST_neighbours_handle_quota_message (const struct GNUNET_PeerIdentity *peer, const struct GNUNET_MessageHeader *msg) { struct NeighbourMapEntry *n; const struct SessionQuotaMessage *sqm; struct GNUNET_BANDWIDTH_Value32NBO bandwidth_min; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received QUOTA message from peer `%s'\n", GNUNET_i2s (peer)); if (ntohs (msg->size) != sizeof (struct SessionQuotaMessage)) { GNUNET_break_op (0); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# quota messages ignored (malformed)"), 1, GNUNET_NO); return; } GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# QUOTA messages received"), 1, GNUNET_NO); sqm = (const struct SessionQuotaMessage *) msg; if (NULL == (n = lookup_neighbour (peer))) { /* gone already */ return; } n->neighbour_receive_quota = GNUNET_BANDWIDTH_value_max (GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT, GNUNET_BANDWIDTH_value_init (ntohl (sqm->quota))); bandwidth_min = GNUNET_BANDWIDTH_value_min (n->primary_address.bandwidth_out, n->neighbour_receive_quota); send_outbound_quota_to_clients (peer, bandwidth_min); } /** * We received a disconnect message from the given peer, * validate and process. * * @param peer sender of the message * @param msg the disconnect message */ void GST_neighbours_handle_disconnect_message (const struct GNUNET_PeerIdentity *peer, const struct GNUNET_MessageHeader *msg) { struct NeighbourMapEntry *n; const struct SessionDisconnectMessage *sdm; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received DISCONNECT message from peer `%s'\n", GNUNET_i2s (peer)); if (ntohs (msg->size) != sizeof (struct SessionDisconnectMessage)) { GNUNET_break_op (0); GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# disconnect messages ignored (malformed)"), 1, GNUNET_NO); return; } GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# DISCONNECT messages received"), 1, GNUNET_NO); sdm = (const struct SessionDisconnectMessage *) msg; if (NULL == (n = lookup_neighbour (peer))) { /* gone already */ return; } if (GNUNET_TIME_absolute_ntoh (sdm->timestamp).abs_value_us <= n->connect_ack_timestamp.abs_value_us) { GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# disconnect messages ignored (timestamp)"), 1, GNUNET_NO); return; } if (0 != memcmp (peer, &sdm->public_key, sizeof (struct GNUNET_PeerIdentity))) { GNUNET_break_op (0); return; } if (ntohl (sdm->purpose.size) != sizeof (struct GNUNET_CRYPTO_EccSignaturePurpose) + sizeof (struct GNUNET_CRYPTO_EddsaPublicKey) + sizeof (struct GNUNET_TIME_AbsoluteNBO)) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "DISCONNECT message from peer `%s' has invalid size\n", GNUNET_i2s (peer)); GNUNET_break_op (0); return; } if (GNUNET_OK != GNUNET_CRYPTO_eddsa_verify (GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT, &sdm->purpose, &sdm->signature, &sdm->public_key)) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "DISCONNECT message from peer `%s' cannot be verified \n", GNUNET_i2s (peer)); GNUNET_break_op (0); return; } if (NULL == n->delayed_disconnect_task) { n->delayed_disconnect_task = GNUNET_SCHEDULER_add_now (&delayed_disconnect, n); } } /** * Closure for the #neighbours_iterate() function. */ struct IteratorContext { /** * Function to call on each connected neighbour. */ GST_NeighbourIterator cb; /** * Closure for @e cb. */ void *cb_cls; }; /** * Call the callback from the closure for each neighbour. * * @param cls the `struct IteratorContext` * @param key the hash of the public key of the neighbour * @param value the `struct NeighbourMapEntry` * @return #GNUNET_OK (continue to iterate) */ static int neighbours_iterate (void *cls, const struct GNUNET_PeerIdentity *key, void *value) { struct IteratorContext *ic = cls; struct NeighbourMapEntry *n = value; struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in; struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out; if (NULL != n->primary_address.address) { bandwidth_in = n->primary_address.bandwidth_in; bandwidth_out = n->primary_address.bandwidth_out; } else { bandwidth_in = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT; bandwidth_out = GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT; } ic->cb (ic->cb_cls, &n->id, n->primary_address.address, n->state, n->timeout, bandwidth_in, bandwidth_out); return GNUNET_OK; } /** * Iterate over all connected neighbours. * * @param cb function to call * @param cb_cls closure for cb */ void GST_neighbours_iterate (GST_NeighbourIterator cb, void *cb_cls) { struct IteratorContext ic; if (NULL == neighbours) return; /* can happen during shutdown */ ic.cb = cb; ic.cb_cls = cb_cls; GNUNET_CONTAINER_multipeermap_iterate (neighbours, &neighbours_iterate, &ic); } /** * If we have an active connection to the given target, it must be shutdown. * * @param target peer to disconnect from */ void GST_neighbours_force_disconnect (const struct GNUNET_PeerIdentity *target) { struct NeighbourMapEntry *n; if (NULL == (n = lookup_neighbour (target))) return; /* not active */ if (GNUNET_YES == test_connected (n)) GNUNET_STATISTICS_update (GST_stats, gettext_noop ("# disconnected from peer upon explicit request"), 1, GNUNET_NO); GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Forced disconnect from peer %s\n", GNUNET_i2s (target)); disconnect_neighbour (n); } /** * Obtain current address information for the given neighbour. * * @param peer * @return address currently used */ struct GNUNET_HELLO_Address * GST_neighbour_get_current_address (const struct GNUNET_PeerIdentity *peer) { struct NeighbourMapEntry *n; n = lookup_neighbour (peer); if (NULL == n) return NULL; return n->primary_address.address; } /** * Initialize the neighbours subsystem. * * @param max_fds maximum number of fds to use */ void GST_neighbours_start (unsigned int max_fds) { neighbours = GNUNET_CONTAINER_multipeermap_create (NEIGHBOUR_TABLE_SIZE, GNUNET_NO); util_transmission_tk = GNUNET_SCHEDULER_add_delayed (UTIL_TRANSMISSION_INTERVAL, &utilization_transmission, NULL); } /** * Disconnect from the given neighbour. * * @param cls unused * @param key hash of neighbour's public key (not used) * @param value the 'struct NeighbourMapEntry' of the neighbour * @return #GNUNET_OK (continue to iterate) */ static int disconnect_all_neighbours (void *cls, const struct GNUNET_PeerIdentity *key, void *value) { struct NeighbourMapEntry *n = value; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting peer `%4s' during shutdown\n", GNUNET_i2s (&n->id)); free_neighbour (n); return GNUNET_OK; } /** * Cleanup the neighbours subsystem. */ void GST_neighbours_stop () { struct BlacklistCheckSwitchContext *cur; struct BlacklistCheckSwitchContext *next; if (NULL == neighbours) return; if (NULL != util_transmission_tk) { GNUNET_SCHEDULER_cancel (util_transmission_tk); util_transmission_tk = NULL; } GNUNET_CONTAINER_multipeermap_iterate (neighbours, &disconnect_all_neighbours, NULL); GNUNET_CONTAINER_multipeermap_destroy (neighbours); neighbours = NULL; next = pending_bc_head; for (cur = next; NULL != cur; cur = next) { next = cur->next; GNUNET_CONTAINER_DLL_remove (pending_bc_head, pending_bc_tail, cur); if (NULL != cur->blc) { GST_blacklist_test_cancel (cur->blc); cur->blc = NULL; } GNUNET_free (cur); } } /* end of file gnunet-service-transport_neighbours.c */