/* SCTP kernel implementation * (C) Copyright IBM Corp. 2001, 2004 * Copyright (c) 1999 Cisco, Inc. * Copyright (c) 1999-2001 Motorola, Inc. * * This file is part of the SCTP kernel implementation * * These functions work with the state functions in sctp_sm_statefuns.c * to implement that state operations. These functions implement the * steps which require modifying existing data structures. * * This SCTP implementation 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 2, or (at your option) * any later version. * * This SCTP implementation 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 GNU CC; see the file COPYING. If not, see * . * * Please send any bug reports or fixes you make to the * email address(es): * lksctp developers * * Written or modified by: * La Monte H.P. Yarroll * Karl Knutson * Jon Grimm * Hui Huang * Dajiang Zhang * Daisy Chang * Sridhar Samudrala * Ardelle Fan */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include static int sctp_cmd_interpreter(sctp_event_t event_type, sctp_subtype_t subtype, sctp_state_t state, struct sctp_endpoint *ep, struct sctp_association *asoc, void *event_arg, sctp_disposition_t status, sctp_cmd_seq_t *commands, gfp_t gfp); static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, sctp_state_t state, struct sctp_endpoint *ep, struct sctp_association **asoc, void *event_arg, sctp_disposition_t status, sctp_cmd_seq_t *commands, gfp_t gfp); static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, struct sctp_transport *t); /******************************************************************** * Helper functions ********************************************************************/ /* A helper function for delayed processing of INET ECN CE bit. */ static void sctp_do_ecn_ce_work(struct sctp_association *asoc, __u32 lowest_tsn) { /* Save the TSN away for comparison when we receive CWR */ asoc->last_ecne_tsn = lowest_tsn; asoc->need_ecne = 1; } /* Helper function for delayed processing of SCTP ECNE chunk. */ /* RFC 2960 Appendix A * * RFC 2481 details a specific bit for a sender to send in * the header of its next outbound TCP segment to indicate to * its peer that it has reduced its congestion window. This * is termed the CWR bit. For SCTP the same indication is made * by including the CWR chunk. This chunk contains one data * element, i.e. the TSN number that was sent in the ECNE chunk. * This element represents the lowest TSN number in the datagram * that was originally marked with the CE bit. */ static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc, __u32 lowest_tsn, struct sctp_chunk *chunk) { struct sctp_chunk *repl; /* Our previously transmitted packet ran into some congestion * so we should take action by reducing cwnd and ssthresh * and then ACK our peer that we we've done so by * sending a CWR. */ /* First, try to determine if we want to actually lower * our cwnd variables. Only lower them if the ECNE looks more * recent than the last response. */ if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) { struct sctp_transport *transport; /* Find which transport's congestion variables * need to be adjusted. */ transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn); /* Update the congestion variables. */ if (transport) sctp_transport_lower_cwnd(transport, SCTP_LOWER_CWND_ECNE); asoc->last_cwr_tsn = lowest_tsn; } /* Always try to quiet the other end. In case of lost CWR, * resend last_cwr_tsn. */ repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk); /* If we run out of memory, it will look like a lost CWR. We'll * get back in sync eventually. */ return repl; } /* Helper function to do delayed processing of ECN CWR chunk. */ static void sctp_do_ecn_cwr_work(struct sctp_association *asoc, __u32 lowest_tsn) { /* Turn off ECNE getting auto-prepended to every outgoing * packet */ asoc->need_ecne = 0; } /* Generate SACK if necessary. We call this at the end of a packet. */ static int sctp_gen_sack(struct sctp_association *asoc, int force, sctp_cmd_seq_t *commands) { __u32 ctsn, max_tsn_seen; struct sctp_chunk *sack; struct sctp_transport *trans = asoc->peer.last_data_from; int error = 0; if (force || (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) || (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE))) asoc->peer.sack_needed = 1; ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map); /* From 12.2 Parameters necessary per association (i.e. the TCB): * * Ack State : This flag indicates if the next received packet * : is to be responded to with a SACK. ... * : When DATA chunks are out of order, SACK's * : are not delayed (see Section 6). * * [This is actually not mentioned in Section 6, but we * implement it here anyway. --piggy] */ if (max_tsn_seen != ctsn) asoc->peer.sack_needed = 1; /* From 6.2 Acknowledgement on Reception of DATA Chunks: * * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, * an acknowledgement SHOULD be generated for at least every * second packet (not every second DATA chunk) received, and * SHOULD be generated within 200 ms of the arrival of any * unacknowledged DATA chunk. ... */ if (!asoc->peer.sack_needed) { asoc->peer.sack_cnt++; /* Set the SACK delay timeout based on the * SACK delay for the last transport * data was received from, or the default * for the association. */ if (trans) { /* We will need a SACK for the next packet. */ if (asoc->peer.sack_cnt >= trans->sackfreq - 1) asoc->peer.sack_needed = 1; asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = trans->sackdelay; } else { /* We will need a SACK for the next packet. */ if (asoc->peer.sack_cnt >= asoc->sackfreq - 1) asoc->peer.sack_needed = 1; asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay; } /* Restart the SACK timer. */ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); } else { __u32 old_a_rwnd = asoc->a_rwnd; asoc->a_rwnd = asoc->rwnd; sack = sctp_make_sack(asoc); if (!sack) { asoc->a_rwnd = old_a_rwnd; goto nomem; } asoc->peer.sack_needed = 0; asoc->peer.sack_cnt = 0; sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack)); /* Stop the SACK timer. */ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); } return error; nomem: error = -ENOMEM; return error; } /* When the T3-RTX timer expires, it calls this function to create the * relevant state machine event. */ void sctp_generate_t3_rtx_event(unsigned long peer) { int error; struct sctp_transport *transport = (struct sctp_transport *) peer; struct sctp_association *asoc = transport->asoc; struct sock *sk = asoc->base.sk; struct net *net = sock_net(sk); /* Check whether a task is in the sock. */ bh_lock_sock(sk); if (sock_owned_by_user(sk)) { pr_debug("%s: sock is busy\n", __func__); /* Try again later. */ if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20))) sctp_transport_hold(transport); goto out_unlock; } /* Run through the state machine. */ error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT, SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX), asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC); if (error) sk->sk_err = -error; out_unlock: bh_unlock_sock(sk); sctp_transport_put(transport); } /* This is a sa interface for producing timeout events. It works * for timeouts which use the association as their parameter. */ static void sctp_generate_timeout_event(struct sctp_association *asoc, sctp_event_timeout_t timeout_type) { struct sock *sk = asoc->base.sk; struct net *net = sock_net(sk); int error = 0; bh_lock_sock(sk); if (sock_owned_by_user(sk)) { pr_debug("%s: sock is busy: timer %d\n", __func__, timeout_type); /* Try again later. */ if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20))) sctp_association_hold(asoc); goto out_unlock; } /* Is this association really dead and just waiting around for * the timer to let go of the reference? */ if (asoc->base.dead) goto out_unlock; /* Run through the state machine. */ error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT, SCTP_ST_TIMEOUT(timeout_type), asoc->state, asoc->ep, asoc, (void *)timeout_type, GFP_ATOMIC); if (error) sk->sk_err = -error; out_unlock: bh_unlock_sock(sk); sctp_association_put(asoc); } static void sctp_generate_t1_cookie_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *) data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE); } static void sctp_generate_t1_init_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *) data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT); } static void sctp_generate_t2_shutdown_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *) data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN); } static void sctp_generate_t4_rto_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *) data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO); } static void sctp_generate_t5_shutdown_guard_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *)data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD); } /* sctp_generate_t5_shutdown_guard_event() */ static void sctp_generate_autoclose_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *) data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE); } /* Generate a heart beat event. If the sock is busy, reschedule. Make * sure that the transport is still valid. */ void sctp_generate_heartbeat_event(unsigned long data) { int error = 0; struct sctp_transport *transport = (struct sctp_transport *) data; struct sctp_association *asoc = transport->asoc; struct sock *sk = asoc->base.sk; struct net *net = sock_net(sk); bh_lock_sock(sk); if (sock_owned_by_user(sk)) { pr_debug("%s: sock is busy\n", __func__); /* Try again later. */ if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20))) sctp_transport_hold(transport); goto out_unlock; } error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT, SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT), asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC); if (error) sk->sk_err = -error; out_unlock: bh_unlock_sock(sk); sctp_transport_put(transport); } /* Handle the timeout of the ICMP protocol unreachable timer. Trigger * the correct state machine transition that will close the association. */ void sctp_generate_proto_unreach_event(unsigned long data) { struct sctp_transport *transport = (struct sctp_transport *) data; struct sctp_association *asoc = transport->asoc; struct sock *sk = asoc->base.sk; struct net *net = sock_net(sk); bh_lock_sock(sk); if (sock_owned_by_user(sk)) { pr_debug("%s: sock is busy\n", __func__); /* Try again later. */ if (!mod_timer(&transport->proto_unreach_timer, jiffies + (HZ/20))) sctp_association_hold(asoc); goto out_unlock; } /* Is this structure just waiting around for us to actually * get destroyed? */ if (asoc->base.dead) goto out_unlock; sctp_do_sm(net, SCTP_EVENT_T_OTHER, SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH), asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC); out_unlock: bh_unlock_sock(sk); sctp_association_put(asoc); } /* Inject a SACK Timeout event into the state machine. */ static void sctp_generate_sack_event(unsigned long data) { struct sctp_association *asoc = (struct sctp_association *) data; sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK); } sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = { NULL, sctp_generate_t1_cookie_event, sctp_generate_t1_init_event, sctp_generate_t2_shutdown_event, NULL, sctp_generate_t4_rto_event, sctp_generate_t5_shutdown_guard_event, NULL, sctp_generate_sack_event, sctp_generate_autoclose_event, }; /* RFC 2960 8.2 Path Failure Detection * * When its peer endpoint is multi-homed, an endpoint should keep a * error counter for each of the destination transport addresses of the * peer endpoint. * * Each time the T3-rtx timer expires on any address, or when a * HEARTBEAT sent to an idle address is not acknowledged within a RTO, * the error counter of that destination address will be incremented. * When the value in the error counter exceeds the protocol parameter * 'Path.Max.Retrans' of that destination address, the endpoint should * mark the destination transport address as inactive, and a * notification SHOULD be sent to the upper layer. * */ static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands, struct sctp_association *asoc, struct sctp_transport *transport, int is_hb) { struct net *net = sock_net(asoc->base.sk); /* The check for association's overall error counter exceeding the * threshold is done in the state function. */ /* We are here due to a timer expiration. If the timer was * not a HEARTBEAT, then normal error tracking is done. * If the timer was a heartbeat, we only increment error counts * when we already have an outstanding HEARTBEAT that has not * been acknowledged. * Additionally, some tranport states inhibit error increments. */ if (!is_hb) { asoc->overall_error_count++; if (transport->state != SCTP_INACTIVE) transport->error_count++; } else if (transport->hb_sent) { if (transport->state != SCTP_UNCONFIRMED) asoc->overall_error_count++; if (transport->state != SCTP_INACTIVE) transport->error_count++; } /* If the transport error count is greater than the pf_retrans * threshold, and less than pathmaxrtx, and if the current state * is SCTP_ACTIVE, then mark this transport as Partially Failed, * see SCTP Quick Failover Draft, section 5.1 */ if (net->sctp.pf_enable && (transport->state == SCTP_ACTIVE) && (asoc->pf_retrans < transport->pathmaxrxt) && (transport->error_count > asoc->pf_retrans)) { sctp_assoc_control_transport(asoc, transport, SCTP_TRANSPORT_PF, 0); /* Update the hb timer to resend a heartbeat every rto */ sctp_cmd_hb_timer_update(commands, transport); } if (transport->state != SCTP_INACTIVE && (transport->error_count > transport->pathmaxrxt)) { pr_debug("%s: association:%p transport addr:%pISpc failed\n", __func__, asoc, &transport->ipaddr.sa); sctp_assoc_control_transport(asoc, transport, SCTP_TRANSPORT_DOWN, SCTP_FAILED_THRESHOLD); } /* E2) For the destination address for which the timer * expires, set RTO <- RTO * 2 ("back off the timer"). The * maximum value discussed in rule C7 above (RTO.max) may be * used to provide an upper bound to this doubling operation. * * Special Case: the first HB doesn't trigger exponential backoff. * The first unacknowledged HB triggers it. We do this with a flag * that indicates that we have an outstanding HB. */ if (!is_hb || transport->hb_sent) { transport->rto = min((transport->rto * 2), transport->asoc->rto_max); sctp_max_rto(asoc, transport); } } /* Worker routine to handle INIT command failure. */ static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands, struct sctp_association *asoc, unsigned int error) { struct sctp_ulpevent *event; event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_CANT_STR_ASSOC, (__u16)error, 0, 0, NULL, GFP_ATOMIC); if (event) sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event)); sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, SCTP_STATE(SCTP_STATE_CLOSED)); /* SEND_FAILED sent later when cleaning up the association. */ asoc->outqueue.error = error; sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); } /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */ static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, struct sctp_association *asoc, sctp_event_t event_type, sctp_subtype_t subtype, struct sctp_chunk *chunk, unsigned int error) { struct sctp_ulpevent *event; struct sctp_chunk *abort; /* Cancel any partial delivery in progress. */ sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT) event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, (__u16)error, 0, 0, chunk, GFP_ATOMIC); else event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, (__u16)error, 0, 0, NULL, GFP_ATOMIC); if (event) sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event)); if (asoc->overall_error_count >= asoc->max_retrans) { abort = sctp_make_violation_max_retrans(asoc, chunk); if (abort) sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); } sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, SCTP_STATE(SCTP_STATE_CLOSED)); /* SEND_FAILED sent later when cleaning up the association. */ asoc->outqueue.error = error; sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); } /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT * inside the cookie. In reality, this is only used for INIT-ACK processing * since all other cases use "temporary" associations and can do all * their work in statefuns directly. */ static int sctp_cmd_process_init(sctp_cmd_seq_t *commands, struct sctp_association *asoc, struct sctp_chunk *chunk, sctp_init_chunk_t *peer_init, gfp_t gfp) { int error; /* We only process the init as a sideeffect in a single * case. This is when we process the INIT-ACK. If we * fail during INIT processing (due to malloc problems), * just return the error and stop processing the stack. */ if (!sctp_process_init(asoc, chunk, sctp_source(chunk), peer_init, gfp)) error = -ENOMEM; else error = 0; return error; } /* Helper function to break out starting up of heartbeat timers. */ static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds, struct sctp_association *asoc) { struct sctp_transport *t; /* Start a heartbeat timer for each transport on the association. * hold a reference on the transport to make sure none of * the needed data structures go away. */ list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) sctp_transport_hold(t); } } static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds, struct sctp_association *asoc) { struct sctp_transport *t; /* Stop all heartbeat timers. */ list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { if (del_timer(&t->hb_timer)) sctp_transport_put(t); } } /* Helper function to stop any pending T3-RTX timers */ static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds, struct sctp_association *asoc) { struct sctp_transport *t; list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { if (del_timer(&t->T3_rtx_timer)) sctp_transport_put(t); } } /* Helper function to update the heartbeat timer. */ static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, struct sctp_transport *t) { /* Update the heartbeat timer. */ if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) sctp_transport_hold(t); } /* Helper function to handle the reception of an HEARTBEAT ACK. */ static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds, struct sctp_association *asoc, struct sctp_transport *t, struct sctp_chunk *chunk) { sctp_sender_hb_info_t *hbinfo; int was_unconfirmed = 0; /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the * HEARTBEAT should clear the error counter of the destination * transport address to which the HEARTBEAT was sent. */ t->error_count = 0; /* * Although RFC4960 specifies that the overall error count must * be cleared when a HEARTBEAT ACK is received, we make an * exception while in SHUTDOWN PENDING. If the peer keeps its * window shut forever, we may never be able to transmit our * outstanding data and rely on the retransmission limit be reached * to shutdown the association. */ if (t->asoc->state < SCTP_STATE_SHUTDOWN_PENDING) t->asoc->overall_error_count = 0; /* Clear the hb_sent flag to signal that we had a good * acknowledgement. */ t->hb_sent = 0; /* Mark the destination transport address as active if it is not so * marked. */ if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) { was_unconfirmed = 1; sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, SCTP_HEARTBEAT_SUCCESS); } if (t->state == SCTP_PF) sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, SCTP_HEARTBEAT_SUCCESS); /* HB-ACK was received for a the proper HB. Consider this * forward progress. */ if (t->dst) dst_confirm(t->dst); /* The receiver of the HEARTBEAT ACK should also perform an * RTT measurement for that destination transport address * using the time value carried in the HEARTBEAT ACK chunk. * If the transport's rto_pending variable has been cleared, * it was most likely due to a retransmit. However, we want * to re-enable it to properly update the rto. */ if (t->rto_pending == 0) t->rto_pending = 1; hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at)); /* Update the heartbeat timer. */ if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) sctp_transport_hold(t); if (was_unconfirmed && asoc->peer.transport_count == 1) sctp_transport_immediate_rtx(t); } /* Helper function to process the process SACK command. */ static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds, struct sctp_association *asoc, struct sctp_chunk *chunk) { int err = 0; if (sctp_outq_sack(&asoc->outqueue, chunk)) { struct net *net = sock_net(asoc->base.sk); /* There are no more TSNs awaiting SACK. */ err = sctp_do_sm(net, SCTP_EVENT_T_OTHER, SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), asoc->state, asoc->ep, asoc, NULL, GFP_ATOMIC); } return err; } /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set * the transport for a shutdown chunk. */ static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds, struct sctp_association *asoc, struct sctp_chunk *chunk) { struct sctp_transport *t; if (chunk->transport) t = chunk->transport; else { t = sctp_assoc_choose_alter_transport(asoc, asoc->shutdown_last_sent_to); chunk->transport = t; } asoc->shutdown_last_sent_to = t; asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto; } /* Helper function to change the state of an association. */ static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, struct sctp_association *asoc, sctp_state_t state) { struct sock *sk = asoc->base.sk; asoc->state = state; pr_debug("%s: asoc:%p[%s]\n", __func__, asoc, sctp_state_tbl[state]); if (sctp_style(sk, TCP)) { /* Change the sk->sk_state of a TCP-style socket that has * successfully completed a connect() call. */ if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED)) sk->sk_state = SCTP_SS_ESTABLISHED; /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */ if (sctp_state(asoc, SHUTDOWN_RECEIVED) && sctp_sstate(sk, ESTABLISHED)) sk->sk_shutdown |= RCV_SHUTDOWN; } if (sctp_state(asoc, COOKIE_WAIT)) { /* Reset init timeouts since they may have been * increased due to timer expirations. */ asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial; asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial; } if (sctp_state(asoc, ESTABLISHED) || sctp_state(asoc, CLOSED) || sctp_state(asoc, SHUTDOWN_RECEIVED)) { /* Wake up any processes waiting in the asoc's wait queue in * sctp_wait_for_connect() or sctp_wait_for_sndbuf(). */ if (waitqueue_active(&asoc->wait)) wake_up_interruptible(&asoc->wait); /* Wake up any processes waiting in the sk's sleep queue of * a TCP-style or UDP-style peeled-off socket in * sctp_wait_for_accept() or sctp_wait_for_packet(). * For a UDP-style socket, the waiters are woken up by the * notifications. */ if (!sctp_style(sk, UDP)) sk->sk_state_change(sk); } } /* Helper function to delete an association. */ static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds, struct sctp_association *asoc) { struct sock *sk = asoc->base.sk; /* If it is a non-temporary association belonging to a TCP-style * listening socket that is not closed, do not free it so that accept() * can pick it up later. */ if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) && (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK)) return; sctp_association_free(asoc); } /* * ADDIP Section 4.1 ASCONF Chunk Procedures * A4) Start a T-4 RTO timer, using the RTO value of the selected * destination address (we use active path instead of primary path just * because primary path may be inactive. */ static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds, struct sctp_association *asoc, struct sctp_chunk *chunk) { struct sctp_transport *t; t = sctp_assoc_choose_alter_transport(asoc, chunk->transport); asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto; chunk->transport = t; } /* Process an incoming Operation Error Chunk. */ static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds, struct sctp_association *asoc, struct sctp_chunk *chunk) { struct sctp_errhdr *err_hdr; struct sctp_ulpevent *ev; while (chunk->chunk_end > chunk->skb->data) { err_hdr = (struct sctp_errhdr *)(chunk->skb->data); ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0, GFP_ATOMIC); if (!ev) return; sctp_ulpq_tail_event(&asoc->ulpq, ev); switch (err_hdr->cause) { case SCTP_ERROR_UNKNOWN_CHUNK: { sctp_chunkhdr_t *unk_chunk_hdr; unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable; switch (unk_chunk_hdr->type) { /* ADDIP 4.1 A9) If the peer responds to an ASCONF with * an ERROR chunk reporting that it did not recognized * the ASCONF chunk type, the sender of the ASCONF MUST * NOT send any further ASCONF chunks and MUST stop its * T-4 timer. */ case SCTP_CID_ASCONF: if (asoc->peer.asconf_capable == 0) break; asoc->peer.asconf_capable = 0; sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); break; default: break; } break; } default: break; } } } /* Process variable FWDTSN chunk information. */ static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk) { struct sctp_fwdtsn_skip *skip; /* Walk through all the skipped SSNs */ sctp_walk_fwdtsn(skip, chunk) { sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn)); } } /* Helper function to remove the association non-primary peer * transports. */ static void sctp_cmd_del_non_primary(struct sctp_association *asoc) { struct sctp_transport *t; struct list_head *pos; struct list_head *temp; list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { t = list_entry(pos, struct sctp_transport, transports); if (!sctp_cmp_addr_exact(&t->ipaddr, &asoc->peer.primary_addr)) { sctp_assoc_rm_peer(asoc, t); } } } /* Helper function to set sk_err on a 1-1 style socket. */ static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) { struct sock *sk = asoc->base.sk; if (!sctp_style(sk, UDP)) sk->sk_err = error; } /* Helper function to generate an association change event */ static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands, struct sctp_association *asoc, u8 state) { struct sctp_ulpevent *ev; ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0, asoc->c.sinit_num_ostreams, asoc->c.sinit_max_instreams, NULL, GFP_ATOMIC); if (ev) sctp_ulpq_tail_event(&asoc->ulpq, ev); } /* Helper function to generate an adaptation indication event */ static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands, struct sctp_association *asoc) { struct sctp_ulpevent *ev; ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); if (ev) sctp_ulpq_tail_event(&asoc->ulpq, ev); } static void sctp_cmd_t1_timer_update(struct sctp_association *asoc, sctp_event_timeout_t timer, char *name) { struct sctp_transport *t; t = asoc->init_last_sent_to; asoc->init_err_counter++; if (t->init_sent_count > (asoc->init_cycle + 1)) { asoc->timeouts[timer] *= 2; if (asoc->timeouts[timer] > asoc->max_init_timeo) { asoc->timeouts[timer] = asoc->max_init_timeo; } asoc->init_cycle++; pr_debug("%s: T1[%s] timeout adjustment init_err_counter:%d" " cycle:%d timeout:%ld\n", __func__, name, asoc->init_err_counter, asoc->init_cycle, asoc->timeouts[timer]); } } /* Send the whole message, chunk by chunk, to the outqueue. * This way the whole message is queued up and bundling if * encouraged for small fragments. */ static int sctp_cmd_send_msg(struct sctp_association *asoc, struct sctp_datamsg *msg, gfp_t gfp) { struct sctp_chunk *chunk; int error = 0; list_for_each_entry(chunk, &msg->chunks, frag_list) { error = sctp_outq_tail(&asoc->outqueue, chunk, gfp); if (error) break; } return error; } /* Sent the next ASCONF packet currently stored in the association. * This happens after the ASCONF_ACK was succeffully processed. */ static void sctp_cmd_send_asconf(struct sctp_association *asoc) { struct net *net = sock_net(asoc->base.sk); /* Send the next asconf chunk from the addip chunk * queue. */ if (!list_empty(&asoc->addip_chunk_list)) { struct list_head *entry = asoc->addip_chunk_list.next; struct sctp_chunk *asconf = list_entry(entry, struct sctp_chunk, list); list_del_init(entry); /* Hold the chunk until an ASCONF_ACK is received. */ sctp_chunk_hold(asconf); if (sctp_primitive_ASCONF(net, asoc, asconf)) sctp_chunk_free(asconf); else asoc->addip_last_asconf = asconf; } } /* These three macros allow us to pull the debugging code out of the * main flow of sctp_do_sm() to keep attention focused on the real * functionality there. */ #define debug_pre_sfn() \ pr_debug("%s[pre-fn]: ep:%p, %s, %s, asoc:%p[%s], %s\n", __func__, \ ep, sctp_evttype_tbl[event_type], (*debug_fn)(subtype), \ asoc, sctp_state_tbl[state], state_fn->name) #define debug_post_sfn() \ pr_debug("%s[post-fn]: asoc:%p, status:%s\n", __func__, asoc, \ sctp_status_tbl[status]) #define debug_post_sfx() \ pr_debug("%s[post-sfx]: error:%d, asoc:%p[%s]\n", __func__, error, \ asoc, sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \ sctp_assoc2id(asoc))) ? asoc->state : SCTP_STATE_CLOSED]) /* * This is the master state machine processing function. * * If you want to understand all of lksctp, this is a * good place to start. */ int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype, sctp_state_t state, struct sctp_endpoint *ep, struct sctp_association *asoc, void *event_arg, gfp_t gfp) { sctp_cmd_seq_t commands; const sctp_sm_table_entry_t *state_fn; sctp_disposition_t status; int error = 0; typedef const char *(printfn_t)(sctp_subtype_t); static printfn_t *table[] = { NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname, }; printfn_t *debug_fn __attribute__ ((unused)) = table[event_type]; /* Look up the state function, run it, and then process the * side effects. These three steps are the heart of lksctp. */ state_fn = sctp_sm_lookup_event(net, event_type, state, subtype); sctp_init_cmd_seq(&commands); debug_pre_sfn(); status = state_fn->fn(net, ep, asoc, subtype, event_arg, &commands); debug_post_sfn(); error = sctp_side_effects(event_type, subtype, state, ep, &asoc, event_arg, status, &commands, gfp); debug_post_sfx(); return error; } /***************************************************************** * This the master state function side effect processing function. *****************************************************************/ static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, sctp_state_t state, struct sctp_endpoint *ep, struct sctp_association **asoc, void *event_arg, sctp_disposition_t status, sctp_cmd_seq_t *commands, gfp_t gfp) { int error; /* FIXME - Most of the dispositions left today would be categorized * as "exceptional" dispositions. For those dispositions, it * may not be proper to run through any of the commands at all. * For example, the command interpreter might be run only with * disposition SCTP_DISPOSITION_CONSUME. */ if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state, ep, *asoc, event_arg, status, commands, gfp))) goto bail; switch (status) { case SCTP_DISPOSITION_DISCARD: pr_debug("%s: ignored sctp protocol event - state:%d, " "event_type:%d, event_id:%d\n", __func__, state, event_type, subtype.chunk); break; case SCTP_DISPOSITION_NOMEM: /* We ran out of memory, so we need to discard this * packet. */ /* BUG--we should now recover some memory, probably by * reneging... */ error = -ENOMEM; break; case SCTP_DISPOSITION_DELETE_TCB: case SCTP_DISPOSITION_ABORT: /* This should now be a command. */ *asoc = NULL; break; case SCTP_DISPOSITION_CONSUME: /* * We should no longer have much work to do here as the * real work has been done as explicit commands above. */ break; case SCTP_DISPOSITION_VIOLATION: net_err_ratelimited("protocol violation state %d chunkid %d\n", state, subtype.chunk); break; case SCTP_DISPOSITION_NOT_IMPL: pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n", state, event_type, subtype.chunk); break; case SCTP_DISPOSITION_BUG: pr_err("bug in state %d, event_type %d, event_id %d\n", state, event_type, subtype.chunk); BUG(); break; default: pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n", status, state, event_type, subtype.chunk); BUG(); break; } bail: return error; } /******************************************************************** * 2nd Level Abstractions ********************************************************************/ /* This is the side-effect interpreter. */ static int sctp_cmd_interpreter(sctp_event_t event_type, sctp_subtype_t subtype, sctp_state_t state, struct sctp_endpoint *ep, struct sctp_association *asoc, void *event_arg, sctp_disposition_t status, sctp_cmd_seq_t *commands, gfp_t gfp) { struct sock *sk = ep->base.sk; struct sctp_sock *sp = sctp_sk(sk); int error = 0; int force; sctp_cmd_t *cmd; struct sctp_chunk *new_obj; struct sctp_chunk *chunk = NULL; struct sctp_packet *packet; struct timer_list *timer; unsigned long timeout; struct sctp_transport *t; struct sctp_sackhdr sackh; int local_cork = 0; if (SCTP_EVENT_T_TIMEOUT != event_type) chunk = event_arg; /* Note: This whole file is a huge candidate for rework. * For example, each command could either have its own handler, so * the loop would look like: * while (cmds) * cmd->handle(x, y, z) * --jgrimm */ while (NULL != (cmd = sctp_next_cmd(commands))) { switch (cmd->verb) { case SCTP_CMD_NOP: /* Do nothing. */ break; case SCTP_CMD_NEW_ASOC: /* Register a new association. */ if (local_cork) { sctp_outq_uncork(&asoc->outqueue, gfp); local_cork = 0; } /* Register with the endpoint. */ asoc = cmd->obj.asoc; BUG_ON(asoc->peer.primary_path == NULL); sctp_endpoint_add_asoc(ep, asoc); break; case SCTP_CMD_UPDATE_ASSOC: sctp_assoc_update(asoc, cmd->obj.asoc); break; case SCTP_CMD_PURGE_OUTQUEUE: sctp_outq_teardown(&asoc->outqueue); break; case SCTP_CMD_DELETE_TCB: if (local_cork) { sctp_outq_uncork(&asoc->outqueue, gfp); local_cork = 0; } /* Delete the current association. */ sctp_cmd_delete_tcb(commands, asoc); asoc = NULL; break; case SCTP_CMD_NEW_STATE: /* Enter a new state. */ sctp_cmd_new_state(commands, asoc, cmd->obj.state); break; case SCTP_CMD_REPORT_TSN: /* Record the arrival of a TSN. */ error = sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32, NULL); break; case SCTP_CMD_REPORT_FWDTSN: /* Move the Cumulattive TSN Ack ahead. */ sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32); /* purge the fragmentation queue */ sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32); /* Abort any in progress partial delivery. */ sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); break; case SCTP_CMD_PROCESS_FWDTSN: sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.chunk); break; case SCTP_CMD_GEN_SACK: /* Generate a Selective ACK. * The argument tells us whether to just count * the packet and MAYBE generate a SACK, or * force a SACK out. */ force = cmd->obj.i32; error = sctp_gen_sack(asoc, force, commands); break; case SCTP_CMD_PROCESS_SACK: /* Process an inbound SACK. */ error = sctp_cmd_process_sack(commands, asoc, cmd->obj.chunk); break; case SCTP_CMD_GEN_INIT_ACK: /* Generate an INIT ACK chunk. */ new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 0); if (!new_obj) goto nomem; sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); break; case SCTP_CMD_PEER_INIT: /* Process a unified INIT from the peer. * Note: Only used during INIT-ACK processing. If * there is an error just return to the outter * layer which will bail. */ error = sctp_cmd_process_init(commands, asoc, chunk, cmd->obj.init, gfp); break; case SCTP_CMD_GEN_COOKIE_ECHO: /* Generate a COOKIE ECHO chunk. */ new_obj = sctp_make_cookie_echo(asoc, chunk); if (!new_obj) { if (cmd->obj.chunk) sctp_chunk_free(cmd->obj.chunk); goto nomem; } sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); /* If there is an ERROR chunk to be sent along with * the COOKIE_ECHO, send it, too. */ if (cmd->obj.chunk) sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(cmd->obj.chunk)); if (new_obj->transport) { new_obj->transport->init_sent_count++; asoc->init_last_sent_to = new_obj->transport; } /* FIXME - Eventually come up with a cleaner way to * enabling COOKIE-ECHO + DATA bundling during * multihoming stale cookie scenarios, the following * command plays with asoc->peer.retran_path to * avoid the problem of sending the COOKIE-ECHO and * DATA in different paths, which could result * in the association being ABORTed if the DATA chunk * is processed first by the server. Checking the * init error counter simply causes this command * to be executed only during failed attempts of * association establishment. */ if ((asoc->peer.retran_path != asoc->peer.primary_path) && (asoc->init_err_counter > 0)) { sctp_add_cmd_sf(commands, SCTP_CMD_FORCE_PRIM_RETRAN, SCTP_NULL()); } break; case SCTP_CMD_GEN_SHUTDOWN: /* Generate SHUTDOWN when in SHUTDOWN_SENT state. * Reset error counts. */ asoc->overall_error_count = 0; /* Generate a SHUTDOWN chunk. */ new_obj = sctp_make_shutdown(asoc, chunk); if (!new_obj) goto nomem; sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); break; case SCTP_CMD_CHUNK_ULP: /* Send a chunk to the sockets layer. */ pr_debug("%s: sm_sideff: chunk_up:%p, ulpq:%p\n", __func__, cmd->obj.chunk, &asoc->ulpq); sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.chunk, GFP_ATOMIC); break; case SCTP_CMD_EVENT_ULP: /* Send a notification to the sockets layer. */ pr_debug("%s: sm_sideff: event_up:%p, ulpq:%p\n", __func__, cmd->obj.ulpevent, &asoc->ulpq); sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ulpevent); break; case SCTP_CMD_REPLY: /* If an caller has not already corked, do cork. */ if (!asoc->outqueue.cork) { sctp_outq_cork(&asoc->outqueue); local_cork = 1; } /* Send a chunk to our peer. */ error = sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk, gfp); break; case SCTP_CMD_SEND_PKT: /* Send a full packet to our peer. */ packet = cmd->obj.packet; sctp_packet_transmit(packet, gfp); sctp_ootb_pkt_free(packet); break; case SCTP_CMD_T1_RETRAN: /* Mark a transport for retransmission. */ sctp_retransmit(&asoc->outqueue, cmd->obj.transport, SCTP_RTXR_T1_RTX); break; case SCTP_CMD_RETRAN: /* Mark a transport for retransmission. */ sctp_retransmit(&asoc->outqueue, cmd->obj.transport, SCTP_RTXR_T3_RTX); break; case SCTP_CMD_ECN_CE: /* Do delayed CE processing. */ sctp_do_ecn_ce_work(asoc, cmd->obj.u32); break; case SCTP_CMD_ECN_ECNE: /* Do delayed ECNE processing. */ new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32, chunk); if (new_obj) sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); break; case SCTP_CMD_ECN_CWR: /* Do delayed CWR processing. */ sctp_do_ecn_cwr_work(asoc, cmd->obj.u32); break; case SCTP_CMD_SETUP_T2: sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk); break; case SCTP_CMD_TIMER_START_ONCE: timer = &asoc->timers[cmd->obj.to]; if (timer_pending(timer)) break; /* fall through */ case SCTP_CMD_TIMER_START: timer = &asoc->timers[cmd->obj.to]; timeout = asoc->timeouts[cmd->obj.to]; BUG_ON(!timeout); timer->expires = jiffies + timeout; sctp_association_hold(asoc); add_timer(timer); break; case SCTP_CMD_TIMER_RESTART: timer = &asoc->timers[cmd->obj.to]; timeout = asoc->timeouts[cmd->obj.to]; if (!mod_timer(timer, jiffies + timeout)) sctp_association_hold(asoc); break; case SCTP_CMD_TIMER_STOP: timer = &asoc->timers[cmd->obj.to]; if (del_timer(timer)) sctp_association_put(asoc); break; case SCTP_CMD_INIT_CHOOSE_TRANSPORT: chunk = cmd->obj.chunk; t = sctp_assoc_choose_alter_transport(asoc, asoc->init_last_sent_to); asoc->init_last_sent_to = t; chunk->transport = t; t->init_sent_count++; /* Set the new transport as primary */ sctp_assoc_set_primary(asoc, t); break; case SCTP_CMD_INIT_RESTART: /* Do the needed accounting and updates * associated with restarting an initialization * timer. Only multiply the timeout by two if * all transports have been tried at the current * timeout. */ sctp_cmd_t1_timer_update(asoc, SCTP_EVENT_TIMEOUT_T1_INIT, "INIT"); sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); break; case SCTP_CMD_COOKIEECHO_RESTART: /* Do the needed accounting and updates * associated with restarting an initialization * timer. Only multiply the timeout by two if * all transports have been tried at the current * timeout. */ sctp_cmd_t1_timer_update(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE, "COOKIE"); /* If we've sent any data bundled with * COOKIE-ECHO we need to resend. */ list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { sctp_retransmit_mark(&asoc->outqueue, t, SCTP_RTXR_T1_RTX); } sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); break; case SCTP_CMD_INIT_FAILED: sctp_cmd_init_failed(commands, asoc, cmd->obj.err); break; case SCTP_CMD_ASSOC_FAILED: sctp_cmd_assoc_failed(commands, asoc, event_type, subtype, chunk, cmd->obj.err); break; case SCTP_CMD_INIT_COUNTER_INC: asoc->init_err_counter++; break; case SCTP_CMD_INIT_COUNTER_RESET: asoc->init_err_counter = 0; asoc->init_cycle = 0; list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { t->init_sent_count = 0; } break; case SCTP_CMD_REPORT_DUP: sctp_tsnmap_mark_dup(&asoc->peer.tsn_map, cmd->obj.u32); break; case SCTP_CMD_REPORT_BAD_TAG: pr_debug("%s: vtag mismatch!\n", __func__); break; case SCTP_CMD_STRIKE: /* Mark one strike against a transport. */ sctp_do_8_2_transport_strike(commands, asoc, cmd->obj.transport, 0); break; case SCTP_CMD_TRANSPORT_IDLE: t = cmd->obj.transport; sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE); break; case SCTP_CMD_TRANSPORT_HB_SENT: t = cmd->obj.transport; sctp_do_8_2_transport_strike(commands, asoc, t, 1); t->hb_sent = 1; break; case SCTP_CMD_TRANSPORT_ON: t = cmd->obj.transport; sctp_cmd_transport_on(commands, asoc, t, chunk); break; case SCTP_CMD_HB_TIMERS_START: sctp_cmd_hb_timers_start(commands, asoc); break; case SCTP_CMD_HB_TIMER_UPDATE: t = cmd->obj.transport; sctp_cmd_hb_timer_update(commands, t); break; case SCTP_CMD_HB_TIMERS_STOP: sctp_cmd_hb_timers_stop(commands, asoc); break; case SCTP_CMD_REPORT_ERROR: error = cmd->obj.error; break; case SCTP_CMD_PROCESS_CTSN: /* Dummy up a SACK for processing. */ sackh.cum_tsn_ack = cmd->obj.be32; sackh.a_rwnd = asoc->peer.rwnd + asoc->outqueue.outstanding_bytes; sackh.num_gap_ack_blocks = 0; sackh.num_dup_tsns = 0; chunk->subh.sack_hdr = &sackh; sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_CHUNK(chunk)); break; case SCTP_CMD_DISCARD_PACKET: /* We need to discard the whole packet. * Uncork the queue since there might be * responses pending */ chunk->pdiscard = 1; if (asoc) { sctp_outq_uncork(&asoc->outqueue, gfp); local_cork = 0; } break; case SCTP_CMD_RTO_PENDING: t = cmd->obj.transport; t->rto_pending = 1; break; case SCTP_CMD_PART_DELIVER: sctp_ulpq_partial_delivery(&asoc->ulpq, GFP_ATOMIC); break; case SCTP_CMD_RENEGE: sctp_ulpq_renege(&asoc->ulpq, cmd->obj.chunk, GFP_ATOMIC); break; case SCTP_CMD_SETUP_T4: sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk); break; case SCTP_CMD_PROCESS_OPERR: sctp_cmd_process_operr(commands, asoc, chunk); break; case SCTP_CMD_CLEAR_INIT_TAG: asoc->peer.i.init_tag = 0; break; case SCTP_CMD_DEL_NON_PRIMARY: sctp_cmd_del_non_primary(asoc); break; case SCTP_CMD_T3_RTX_TIMERS_STOP: sctp_cmd_t3_rtx_timers_stop(commands, asoc); break; case SCTP_CMD_FORCE_PRIM_RETRAN: t = asoc->peer.retran_path; asoc->peer.retran_path = asoc->peer.primary_path; error = sctp_outq_uncork(&asoc->outqueue, gfp); local_cork = 0; asoc->peer.retran_path = t; break; case SCTP_CMD_SET_SK_ERR: sctp_cmd_set_sk_err(asoc, cmd->obj.error); break; case SCTP_CMD_ASSOC_CHANGE: sctp_cmd_assoc_change(commands, asoc, cmd->obj.u8); break; case SCTP_CMD_ADAPTATION_IND: sctp_cmd_adaptation_ind(commands, asoc); break; case SCTP_CMD_ASSOC_SHKEY: error = sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); break; case SCTP_CMD_UPDATE_INITTAG: asoc->peer.i.init_tag = cmd->obj.u32; break; case SCTP_CMD_SEND_MSG: if (!asoc->outqueue.cork) { sctp_outq_cork(&asoc->outqueue); local_cork = 1; } error = sctp_cmd_send_msg(asoc, cmd->obj.msg, gfp); break; case SCTP_CMD_SEND_NEXT_ASCONF: sctp_cmd_send_asconf(asoc); break; case SCTP_CMD_PURGE_ASCONF_QUEUE: sctp_asconf_queue_teardown(asoc); break; case SCTP_CMD_SET_ASOC: asoc = cmd->obj.asoc; break; default: pr_warn("Impossible command: %u\n", cmd->verb); break; } if (error) break; } out: /* If this is in response to a received chunk, wait until * we are done with the packet to open the queue so that we don't * send multiple packets in response to a single request. */ if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) { if (chunk->end_of_packet || chunk->singleton) error = sctp_outq_uncork(&asoc->outqueue, gfp); } else if (local_cork) error = sctp_outq_uncork(&asoc->outqueue, gfp); if (sp->pending_data_ready) { sk->sk_data_ready(sk); sp->pending_data_ready = 0; } return error; nomem: error = -ENOMEM; goto out; }