cregit-Linux how code gets into the kernel

Release 4.11 net/sctp/sm_sideeffect.c

Directory: net/sctp
/* 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
 * <http://www.gnu.org/licenses/>.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <linux-sctp@vger.kernel.org>
 *
 * 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>
 */


#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);

/********************************************************************
 * 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;
}


Contributors
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Jon Grimm2696.30%375.00%


David S. Miller13.70%125.00%


Total27100.00%4100.00%



/* 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm9198.91%583.33%


David S. Miller11.09%116.67%


Total92100.00%6100.00%



/* 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2095.24%375.00%


Sridhar Samudrala14.76%125.00%


Total21100.00%4100.00%



/* 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm16450.46%440.00%


Frank Filz7723.69%110.00%


Wei Yongjun6018.46%110.00%


Marcelo Ricardo Leitner154.62%110.00%


Vladislav Yasevich72.15%110.00%


Sridhar Samudrala20.62%220.00%


Total325100.00%10100.00%



/* 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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm12278.21%327.27%


Eric W. Biedermann127.69%19.09%


Karl Heiss117.05%19.09%


David S. Miller31.92%19.09%


Sridhar Samudrala21.28%19.09%


Daniel Borkmann21.28%19.09%


Wang Weidong21.28%19.09%


Arnaldo Carvalho de Melo10.64%19.09%


Harvey Harrison10.64%19.09%


Total156100.00%11100.00%



/* 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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm13382.10%333.33%


Eric W. Biedermann127.41%111.11%


Karl Heiss116.79%111.11%


Daniel Borkmann21.23%111.11%


Wang Weidong21.23%111.11%


Arnaldo Carvalho de Melo10.62%111.11%


Harvey Harrison10.62%111.11%


Total162100.00%9100.00%






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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2896.55%375.00%


Sridhar Samudrala13.45%125.00%


Total29100.00%4100.00%






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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2896.55%375.00%


Sridhar Samudrala13.45%125.00%


Total29100.00%4100.00%






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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2586.21%360.00%


Sridhar Samudrala413.79%240.00%


Total29100.00%5100.00%






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);
}


Contributors
PersonTokensPropCommitsCommitProp
Sridhar Samudrala29100.00%2100.00%


Total29100.00%2100.00%






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);

} 
Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2896.55%375.00%


Sridhar Samudrala13.45%125.00%


Total29100.00%4100.00%



/* 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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2896.55%375.00%


Sridhar Samudrala13.45%125.00%


Total29100.00%4100.00%



/* 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);
	u32 elapsed, timeout;

	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;
	}

	/* Check if we should still send the heartbeat or reschedule */
	elapsed = jiffies - transport->last_time_sent;
	timeout = sctp_transport_timeout(transport);
	if (elapsed < timeout) {
		elapsed = timeout - elapsed;
		if (!mod_timer(&transport->hb_timer, jiffies + elapsed))
			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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm12357.48%433.33%


Marcelo Ricardo Leitner5827.10%18.33%


Eric W. Biedermann125.61%18.33%


Karl Heiss115.14%18.33%


Daisy Chang41.87%18.33%


Wang Weidong20.93%18.33%


Daniel Borkmann20.93%18.33%


Harvey Harrison10.47%18.33%


Arnaldo Carvalho de Melo10.47%18.33%


Total214100.00%12100.00%



/* 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);
}

 
Contributors
PersonTokensPropCommitsCommitProp
Vladislav Yasevich12382.00%120.00%


Eric W. Biedermann128.00%120.00%


Karl Heiss117.33%120.00%


Wang Weidong21.33%120.00%


Daniel Borkmann21.33%120.00%


Total150100.00%5100.00%



/* Handle the timeout of the RE-CONFIG timer. */



void sctp_generate_reconf_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);
	int error = 0;

	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->reconf_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_RECONF),
			   asoc->state, asoc->ep, asoc,
			   transport, GFP_ATOMIC);

	if (error)
		sk->sk_err = -error;

out_unlock:
	bh_unlock_sock(sk);
	sctp_transport_put(transport);
}


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Xin Long156100.00%1100.00%


Total156100.00%1100.00%



/* 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);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2482.76%250.00%


Daisy Chang413.79%125.00%


Sridhar Samudrala13.45%125.00%


Total29100.00%4100.00%




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,
	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_transport_reset_hb_timer(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);
	}
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm7229.75%315.79%


Vladislav Yasevich6225.62%315.79%


Neil Horman4719.42%15.26%


Zhu Yanjun208.26%15.26%


Frank Filz114.55%210.53%


Sridhar Samudrala83.31%15.26%


Michele Baldessari72.89%15.26%


Daniel Borkmann41.65%15.26%


Karl Heiss31.24%15.26%


Matija Glavinic Pecotic31.24%15.26%


Al Viro20.83%15.26%


Lucas De Marchi10.41%15.26%


Marcelo Ricardo Leitner10.41%15.26%


Daniel Mack10.41%15.26%


Total242100.00%19100.00%



/* 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());
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm8084.21%562.50%


Sridhar Samudrala1212.63%112.50%


Vladislav Yasevich22.11%112.50%


Eric Dumazet11.05%112.50%


Total95100.00%8100.00%



/* 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());
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm11357.65%450.00%


Neil Horman4221.43%112.50%


Vladislav Yasevich3919.90%112.50%


Sridhar Samudrala10.51%112.50%


Eric Dumazet10.51%112.50%


Total196100.00%8100.00%



/* 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm6298.41%375.00%


Al Viro11.59%125.00%


Total63100.00%4100.00%



/* 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)
		sctp_transport_reset_hb_timer(t);
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm2779.41%350.00%


Robert P. J. Day38.82%116.67%


Sridhar Samudrala38.82%116.67%


Marcelo Ricardo Leitner12.94%116.67%


Total34100.00%6100.00%






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);
	}
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm4291.30%480.00%


Robert P. J. Day48.70%120.00%


Total46100.00%5100.00%



/* 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);
	}
}



Contributors
PersonTokensPropCommitsCommitProp
Sridhar Samudrala4191.11%150.00%


Robert P. J. Day48.89%150.00%


Total45100.00%2100.00%



/* 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)
		sctp_transport_dst_confirm(t);

	/* 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.  */
	sctp_transport_reset_hb_timer(t);

	if (was_unconfirmed && asoc->peer.transport_count == 1)
		sctp_transport_immediate_rtx(t);
}



Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm8040.61%633.33%


Michio Honda2814.21%15.56%


Vladislav Yasevich2211.17%211.11%


Sridhar Samudrala2010.15%211.11%


Neil Horman199.64%15.56%


Daniel Borkmann115.58%15.56%


Thomas Graf115.58%15.56%


Frank Filz31.52%15.56%


Julian Anastasov10.51%15.56%


Marcelo Ricardo Leitner10.51%15.56%


Xin Long10.51%15.56%


Total197100.00%18100.00%



/* 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm6374.12%450.00%


Eric W. Biedermann1618.82%112.50%


Nicolas Dichtel33.53%112.50%


Vladislav Yasevich22.35%112.50%


Sridhar Samudrala11.18%112.50%


Total85100.00%8100.00%



/* 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;
}


Contributors
PersonTokensPropCommitsCommitProp
Jon Grimm4864.86%466.67%


Vladislav Yasevich2128.38%116.67%


Wei Yongjun56.76%116.67%


Total74100.00%6100.00%



/* 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_state = SCTP_SS_CLOSING;
			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