| /* 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, write to |
| * the Free Software Foundation, 59 Temple Place - Suite 330, |
| * Boston, MA 02111-1307, USA. |
| * |
| * Please send any bug reports or fixes you make to the |
| * email address(es): |
| * lksctp developers <lksctp-developers@lists.sourceforge.net> |
| * |
| * Or submit a bug report through the following website: |
| * http://www.sf.net/projects/lksctp |
| * |
| * Written or modified by: |
| * La Monte H.P. Yarroll <piggy@acm.org> |
| * Karl Knutson <karl@athena.chicago.il.us> |
| * Jon Grimm <jgrimm@austin.ibm.com> |
| * Hui Huang <hui.huang@nokia.com> |
| * Dajiang Zhang <dajiang.zhang@nokia.com> |
| * Daisy Chang <daisyc@us.ibm.com> |
| * Sridhar Samudrala <sri@us.ibm.com> |
| * Ardelle Fan <ardelle.fan@intel.com> |
| * |
| * Any bugs reported given to us we will try to fix... any fixes shared will |
| * be incorporated into the next SCTP release. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/skbuff.h> |
| #include <linux/types.h> |
| #include <linux/socket.h> |
| #include <linux/ip.h> |
| #include <linux/gfp.h> |
| #include <net/sock.h> |
| #include <net/sctp/sctp.h> |
| #include <net/sctp/sm.h> |
| |
| 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 { |
| asoc->a_rwnd = asoc->rwnd; |
| sack = sctp_make_sack(asoc); |
| if (!sack) |
| 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 net *net = sock_net(asoc->base.sk); |
| |
| /* Check whether a task is in the sock. */ |
| |
| sctp_bh_lock_sock(asoc->base.sk); |
| if (sock_owned_by_user(asoc->base.sk)) { |
| SCTP_DEBUG_PRINTK("%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; |
| } |
| |
| /* Is this transport really dead and just waiting around for |
| * the timer to let go of the reference? |
| */ |
| if (transport->dead) |
| 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) |
| asoc->base.sk->sk_err = -error; |
| |
| out_unlock: |
| sctp_bh_unlock_sock(asoc->base.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 net *net = sock_net(asoc->base.sk); |
| int error = 0; |
| |
| sctp_bh_lock_sock(asoc->base.sk); |
| if (sock_owned_by_user(asoc->base.sk)) { |
| SCTP_DEBUG_PRINTK("%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) |
| asoc->base.sk->sk_err = -error; |
| |
| out_unlock: |
| sctp_bh_unlock_sock(asoc->base.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 net *net = sock_net(asoc->base.sk); |
| |
| sctp_bh_lock_sock(asoc->base.sk); |
| if (sock_owned_by_user(asoc->base.sk)) { |
| SCTP_DEBUG_PRINTK("%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; |
| } |
| |
| /* Is this structure just waiting around for us to actually |
| * get destroyed? |
| */ |
| if (transport->dead) |
| 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) |
| asoc->base.sk->sk_err = -error; |
| |
| out_unlock: |
| sctp_bh_unlock_sock(asoc->base.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 net *net = sock_net(asoc->base.sk); |
| |
| sctp_bh_lock_sock(asoc->base.sk); |
| if (sock_owned_by_user(asoc->base.sk)) { |
| SCTP_DEBUG_PRINTK("%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: |
| sctp_bh_unlock_sock(asoc->base.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) |
| { |
| /* 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, then mark this transport |
| * as Partially Failed, ee SCTP Quick Failover Draft, secon 5.1, |
| * point 1 |
| */ |
| if ((transport->state != SCTP_PF) && |
| (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)) { |
| SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p", |
| " transport IP: port:%d failed.\n", |
| asoc, |
| (&transport->ipaddr), |
| ntohs(transport->ipaddr.v4.sin_port)); |
| 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); |
| } |
| } |
| |
| /* 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; |
| |
| /* 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)); |
| |
| 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 (timer_pending(&t->T3_rtx_timer) && |
| 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); |
| |
| /* 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_sackhdr *sackh) |
| { |
| int err = 0; |
| |
| if (sctp_outq_sack(&asoc->outqueue, sackh)) { |
| 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; |
| |
| SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n", |
| 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_unhash_established(asoc); |
| 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_del_peer(asoc, &t->ipaddr); |
| } |
| } |
| } |
| |
| /* 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++; |
| SCTP_DEBUG_PRINTK( |
| "T1 %s Timeout adjustment" |
| " init_err_counter: %d" |
| " cycle: %d" |
| " timeout: %ld\n", |
| 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) |
| { |
| struct sctp_chunk *chunk; |
| int error = 0; |
| |
| list_for_each_entry(chunk, &msg->chunks, frag_list) { |
| error = sctp_outq_tail(&asoc->outqueue, chunk); |
| 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 \ |
| SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \ |
| "ep %p, %s, %s, asoc %p[%s], %s\n", \ |
| ep, sctp_evttype_tbl[event_type], \ |
| (*debug_fn)(subtype), asoc, \ |
| sctp_state_tbl[state], state_fn->name) |
| |
| #define DEBUG_POST \ |
| SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \ |
| "asoc %p, status: %s\n", \ |
| asoc, sctp_status_tbl[status]) |
| |
| #define DEBUG_POST_SFX \ |
| SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \ |
| 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; |
| status = (*state_fn->fn)(net, ep, asoc, subtype, event_arg, &commands); |
| DEBUG_POST; |
| |
| error = sctp_side_effects(event_type, subtype, state, |
| ep, asoc, event_arg, status, |
| &commands, gfp); |
| DEBUG_POST_SFX; |
| |
| return error; |
| } |
| |
| #undef DEBUG_PRE |
| #undef DEBUG_POST |
| |
| /***************************************************************** |
| * 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: |
| SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, " |
| "event_type %d, event_id %d\n", |
| 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: |
| /* This should now be a command. */ |
| break; |
| |
| case SCTP_DISPOSITION_CONSUME: |
| case SCTP_DISPOSITION_ABORT: |
| /* |
| * 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) |
| { |
| 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); |
| local_cork = 0; |
| } |
| asoc = cmd->obj.ptr; |
| /* Register with the endpoint. */ |
| sctp_endpoint_add_asoc(ep, asoc); |
| sctp_hash_established(asoc); |
| break; |
| |
| case SCTP_CMD_UPDATE_ASSOC: |
| sctp_assoc_update(asoc, cmd->obj.ptr); |
| 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); |
| 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.ptr); |
| 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.ptr); |
| 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.ptr, 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.ptr) |
| sctp_chunk_free(cmd->obj.ptr); |
| 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.ptr) |
| sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
| SCTP_CHUNK(cmd->obj.ptr)); |
| |
| 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. */ |
| SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", |
| "chunk_up:", cmd->obj.ptr, |
| "ulpq:", &asoc->ulpq); |
| sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr, |
| GFP_ATOMIC); |
| break; |
| |
| case SCTP_CMD_EVENT_ULP: |
| /* Send a notification to the sockets layer. */ |
| SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", |
| "event_up:",cmd->obj.ptr, |
| "ulpq:",&asoc->ulpq); |
| sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr); |
| 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.ptr); |
| break; |
| |
| case SCTP_CMD_SEND_PKT: |
| /* Send a full packet to our peer. */ |
| packet = cmd->obj.ptr; |
| sctp_packet_transmit(packet); |
| 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.ptr); |
| 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 (timer_pending(timer) && del_timer(timer)) |
| sctp_association_put(asoc); |
| break; |
| |
| case SCTP_CMD_INIT_CHOOSE_TRANSPORT: |
| chunk = cmd->obj.ptr; |
| 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: |
| SCTP_DEBUG_PRINTK("vtag mismatch!\n"); |
| 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; |
| sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, |
| SCTP_SACKH(&sackh)); |
| 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); |
| 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, cmd->obj.ptr, |
| GFP_ATOMIC); |
| break; |
| |
| case SCTP_CMD_RENEGE: |
| sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr, |
| GFP_ATOMIC); |
| break; |
| |
| case SCTP_CMD_SETUP_T4: |
| sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr); |
| 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); |
| 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); |
| 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, %p\n", |
| cmd->verb, cmd->obj.ptr); |
| 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); |
| } else if (local_cork) |
| error = sctp_outq_uncork(&asoc->outqueue); |
| return error; |
| nomem: |
| error = -ENOMEM; |
| goto out; |
| } |
| |