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4c31bc6b1e
'addr' passed to sctp_transport_init is not always a whole size of union sctp_addr, like the path: sctp_sendmsg() -> sctp_sendmsg_new_asoc() -> sctp_assoc_add_peer() -> sctp_transport_new() -> sctp_transport_init() In the next patches, we will also pass the address length of data only to sctp_assoc_add_peer(). So sctp_transport_init() should copy the only available data from addr to peer->ipaddr, instead of 'peer->ipaddr = *addr' which may cause slab-out-of-bounds. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
697 lines
21 KiB
C
697 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/* SCTP kernel implementation
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* Copyright (c) 1999-2000 Cisco, Inc.
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* Copyright (c) 1999-2001 Motorola, Inc.
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* Copyright (c) 2001-2003 International Business Machines Corp.
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* Copyright (c) 2001 Intel Corp.
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* Copyright (c) 2001 La Monte H.P. Yarroll
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*
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* This file is part of the SCTP kernel implementation
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*
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* This module provides the abstraction for an SCTP tranport representing
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* a remote transport address. For local transport addresses, we just use
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* union sctp_addr.
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*
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* Please send any bug reports or fixes you make to the
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* email address(es):
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* lksctp developers <linux-sctp@vger.kernel.org>
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*
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* Written or modified by:
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* La Monte H.P. Yarroll <piggy@acm.org>
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* Karl Knutson <karl@athena.chicago.il.us>
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* Jon Grimm <jgrimm@us.ibm.com>
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* Xingang Guo <xingang.guo@intel.com>
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* Hui Huang <hui.huang@nokia.com>
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* Sridhar Samudrala <sri@us.ibm.com>
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* Ardelle Fan <ardelle.fan@intel.com>
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/slab.h>
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#include <linux/types.h>
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#include <linux/random.h>
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#include <net/sctp/sctp.h>
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#include <net/sctp/sm.h>
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/* 1st Level Abstractions. */
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/* Initialize a new transport from provided memory. */
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static struct sctp_transport *sctp_transport_init(struct net *net,
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struct sctp_transport *peer,
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const union sctp_addr *addr,
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gfp_t gfp)
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{
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/* Copy in the address. */
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peer->af_specific = sctp_get_af_specific(addr->sa.sa_family);
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memcpy(&peer->ipaddr, addr, peer->af_specific->sockaddr_len);
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memset(&peer->saddr, 0, sizeof(union sctp_addr));
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peer->sack_generation = 0;
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/* From 6.3.1 RTO Calculation:
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*
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* C1) Until an RTT measurement has been made for a packet sent to the
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* given destination transport address, set RTO to the protocol
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* parameter 'RTO.Initial'.
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*/
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peer->rto = msecs_to_jiffies(net->sctp.rto_initial);
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peer->last_time_heard = 0;
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peer->last_time_ecne_reduced = jiffies;
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peer->param_flags = SPP_HB_DISABLE |
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SPP_PMTUD_ENABLE |
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SPP_SACKDELAY_ENABLE;
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/* Initialize the default path max_retrans. */
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peer->pathmaxrxt = net->sctp.max_retrans_path;
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peer->pf_retrans = net->sctp.pf_retrans;
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INIT_LIST_HEAD(&peer->transmitted);
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INIT_LIST_HEAD(&peer->send_ready);
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INIT_LIST_HEAD(&peer->transports);
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timer_setup(&peer->T3_rtx_timer, sctp_generate_t3_rtx_event, 0);
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timer_setup(&peer->hb_timer, sctp_generate_heartbeat_event, 0);
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timer_setup(&peer->reconf_timer, sctp_generate_reconf_event, 0);
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timer_setup(&peer->proto_unreach_timer,
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sctp_generate_proto_unreach_event, 0);
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/* Initialize the 64-bit random nonce sent with heartbeat. */
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get_random_bytes(&peer->hb_nonce, sizeof(peer->hb_nonce));
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refcount_set(&peer->refcnt, 1);
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return peer;
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}
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/* Allocate and initialize a new transport. */
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struct sctp_transport *sctp_transport_new(struct net *net,
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const union sctp_addr *addr,
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gfp_t gfp)
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{
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struct sctp_transport *transport;
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transport = kzalloc(sizeof(*transport), gfp);
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if (!transport)
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goto fail;
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if (!sctp_transport_init(net, transport, addr, gfp))
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goto fail_init;
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SCTP_DBG_OBJCNT_INC(transport);
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return transport;
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fail_init:
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kfree(transport);
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fail:
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return NULL;
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}
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/* This transport is no longer needed. Free up if possible, or
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* delay until it last reference count.
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*/
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void sctp_transport_free(struct sctp_transport *transport)
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{
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/* Try to delete the heartbeat timer. */
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if (del_timer(&transport->hb_timer))
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sctp_transport_put(transport);
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/* Delete the T3_rtx timer if it's active.
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* There is no point in not doing this now and letting
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* structure hang around in memory since we know
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* the tranport is going away.
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*/
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if (del_timer(&transport->T3_rtx_timer))
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sctp_transport_put(transport);
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if (del_timer(&transport->reconf_timer))
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sctp_transport_put(transport);
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/* Delete the ICMP proto unreachable timer if it's active. */
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if (del_timer(&transport->proto_unreach_timer))
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sctp_association_put(transport->asoc);
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sctp_transport_put(transport);
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}
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static void sctp_transport_destroy_rcu(struct rcu_head *head)
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{
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struct sctp_transport *transport;
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transport = container_of(head, struct sctp_transport, rcu);
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dst_release(transport->dst);
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kfree(transport);
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SCTP_DBG_OBJCNT_DEC(transport);
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}
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/* Destroy the transport data structure.
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* Assumes there are no more users of this structure.
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*/
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static void sctp_transport_destroy(struct sctp_transport *transport)
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{
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if (unlikely(refcount_read(&transport->refcnt))) {
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WARN(1, "Attempt to destroy undead transport %p!\n", transport);
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return;
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}
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sctp_packet_free(&transport->packet);
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if (transport->asoc)
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sctp_association_put(transport->asoc);
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call_rcu(&transport->rcu, sctp_transport_destroy_rcu);
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}
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/* Start T3_rtx timer if it is not already running and update the heartbeat
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* timer. This routine is called every time a DATA chunk is sent.
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*/
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void sctp_transport_reset_t3_rtx(struct sctp_transport *transport)
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{
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/* RFC 2960 6.3.2 Retransmission Timer Rules
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*
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* R1) Every time a DATA chunk is sent to any address(including a
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* retransmission), if the T3-rtx timer of that address is not running
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* start it running so that it will expire after the RTO of that
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* address.
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*/
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if (!timer_pending(&transport->T3_rtx_timer))
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if (!mod_timer(&transport->T3_rtx_timer,
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jiffies + transport->rto))
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sctp_transport_hold(transport);
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}
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void sctp_transport_reset_hb_timer(struct sctp_transport *transport)
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{
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unsigned long expires;
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/* When a data chunk is sent, reset the heartbeat interval. */
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expires = jiffies + sctp_transport_timeout(transport);
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if ((time_before(transport->hb_timer.expires, expires) ||
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!timer_pending(&transport->hb_timer)) &&
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!mod_timer(&transport->hb_timer,
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expires + prandom_u32_max(transport->rto)))
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sctp_transport_hold(transport);
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}
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void sctp_transport_reset_reconf_timer(struct sctp_transport *transport)
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{
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if (!timer_pending(&transport->reconf_timer))
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if (!mod_timer(&transport->reconf_timer,
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jiffies + transport->rto))
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sctp_transport_hold(transport);
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}
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/* This transport has been assigned to an association.
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* Initialize fields from the association or from the sock itself.
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* Register the reference count in the association.
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*/
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void sctp_transport_set_owner(struct sctp_transport *transport,
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struct sctp_association *asoc)
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{
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transport->asoc = asoc;
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sctp_association_hold(asoc);
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}
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/* Initialize the pmtu of a transport. */
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void sctp_transport_pmtu(struct sctp_transport *transport, struct sock *sk)
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{
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/* If we don't have a fresh route, look one up */
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if (!transport->dst || transport->dst->obsolete) {
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sctp_transport_dst_release(transport);
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transport->af_specific->get_dst(transport, &transport->saddr,
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&transport->fl, sk);
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}
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if (transport->param_flags & SPP_PMTUD_DISABLE) {
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struct sctp_association *asoc = transport->asoc;
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if (!transport->pathmtu && asoc && asoc->pathmtu)
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transport->pathmtu = asoc->pathmtu;
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if (transport->pathmtu)
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return;
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}
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if (transport->dst)
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transport->pathmtu = sctp_dst_mtu(transport->dst);
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else
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transport->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
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}
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bool sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu)
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{
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struct dst_entry *dst = sctp_transport_dst_check(t);
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struct sock *sk = t->asoc->base.sk;
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bool change = true;
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if (unlikely(pmtu < SCTP_DEFAULT_MINSEGMENT)) {
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pr_warn_ratelimited("%s: Reported pmtu %d too low, using default minimum of %d\n",
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__func__, pmtu, SCTP_DEFAULT_MINSEGMENT);
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/* Use default minimum segment instead */
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pmtu = SCTP_DEFAULT_MINSEGMENT;
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}
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pmtu = SCTP_TRUNC4(pmtu);
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if (dst) {
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struct sctp_pf *pf = sctp_get_pf_specific(dst->ops->family);
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union sctp_addr addr;
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pf->af->from_sk(&addr, sk);
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pf->to_sk_daddr(&t->ipaddr, sk);
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dst->ops->update_pmtu(dst, sk, NULL, pmtu);
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pf->to_sk_daddr(&addr, sk);
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dst = sctp_transport_dst_check(t);
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}
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if (!dst) {
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t->af_specific->get_dst(t, &t->saddr, &t->fl, sk);
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dst = t->dst;
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}
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if (dst) {
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/* Re-fetch, as under layers may have a higher minimum size */
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pmtu = sctp_dst_mtu(dst);
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change = t->pathmtu != pmtu;
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}
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t->pathmtu = pmtu;
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return change;
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}
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/* Caches the dst entry and source address for a transport's destination
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* address.
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*/
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void sctp_transport_route(struct sctp_transport *transport,
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union sctp_addr *saddr, struct sctp_sock *opt)
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{
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struct sctp_association *asoc = transport->asoc;
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struct sctp_af *af = transport->af_specific;
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sctp_transport_dst_release(transport);
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af->get_dst(transport, saddr, &transport->fl, sctp_opt2sk(opt));
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if (saddr)
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memcpy(&transport->saddr, saddr, sizeof(union sctp_addr));
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else
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af->get_saddr(opt, transport, &transport->fl);
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sctp_transport_pmtu(transport, sctp_opt2sk(opt));
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/* Initialize sk->sk_rcv_saddr, if the transport is the
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* association's active path for getsockname().
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*/
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if (transport->dst && asoc &&
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(!asoc->peer.primary_path || transport == asoc->peer.active_path))
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opt->pf->to_sk_saddr(&transport->saddr, asoc->base.sk);
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}
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/* Hold a reference to a transport. */
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int sctp_transport_hold(struct sctp_transport *transport)
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{
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return refcount_inc_not_zero(&transport->refcnt);
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}
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/* Release a reference to a transport and clean up
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* if there are no more references.
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*/
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void sctp_transport_put(struct sctp_transport *transport)
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{
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if (refcount_dec_and_test(&transport->refcnt))
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sctp_transport_destroy(transport);
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}
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/* Update transport's RTO based on the newly calculated RTT. */
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void sctp_transport_update_rto(struct sctp_transport *tp, __u32 rtt)
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{
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if (unlikely(!tp->rto_pending))
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/* We should not be doing any RTO updates unless rto_pending is set. */
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pr_debug("%s: rto_pending not set on transport %p!\n", __func__, tp);
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if (tp->rttvar || tp->srtt) {
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struct net *net = sock_net(tp->asoc->base.sk);
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/* 6.3.1 C3) When a new RTT measurement R' is made, set
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* RTTVAR <- (1 - RTO.Beta) * RTTVAR + RTO.Beta * |SRTT - R'|
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* SRTT <- (1 - RTO.Alpha) * SRTT + RTO.Alpha * R'
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*/
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/* Note: The above algorithm has been rewritten to
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* express rto_beta and rto_alpha as inverse powers
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* of two.
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* For example, assuming the default value of RTO.Alpha of
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* 1/8, rto_alpha would be expressed as 3.
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*/
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tp->rttvar = tp->rttvar - (tp->rttvar >> net->sctp.rto_beta)
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+ (((__u32)abs((__s64)tp->srtt - (__s64)rtt)) >> net->sctp.rto_beta);
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tp->srtt = tp->srtt - (tp->srtt >> net->sctp.rto_alpha)
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+ (rtt >> net->sctp.rto_alpha);
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} else {
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/* 6.3.1 C2) When the first RTT measurement R is made, set
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* SRTT <- R, RTTVAR <- R/2.
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*/
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tp->srtt = rtt;
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tp->rttvar = rtt >> 1;
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}
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/* 6.3.1 G1) Whenever RTTVAR is computed, if RTTVAR = 0, then
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* adjust RTTVAR <- G, where G is the CLOCK GRANULARITY.
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*/
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if (tp->rttvar == 0)
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tp->rttvar = SCTP_CLOCK_GRANULARITY;
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/* 6.3.1 C3) After the computation, update RTO <- SRTT + 4 * RTTVAR. */
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tp->rto = tp->srtt + (tp->rttvar << 2);
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/* 6.3.1 C6) Whenever RTO is computed, if it is less than RTO.Min
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* seconds then it is rounded up to RTO.Min seconds.
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*/
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if (tp->rto < tp->asoc->rto_min)
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tp->rto = tp->asoc->rto_min;
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/* 6.3.1 C7) A maximum value may be placed on RTO provided it is
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* at least RTO.max seconds.
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*/
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if (tp->rto > tp->asoc->rto_max)
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tp->rto = tp->asoc->rto_max;
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sctp_max_rto(tp->asoc, tp);
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tp->rtt = rtt;
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/* Reset rto_pending so that a new RTT measurement is started when a
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* new data chunk is sent.
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*/
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tp->rto_pending = 0;
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pr_debug("%s: transport:%p, rtt:%d, srtt:%d rttvar:%d, rto:%ld\n",
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__func__, tp, rtt, tp->srtt, tp->rttvar, tp->rto);
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}
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/* This routine updates the transport's cwnd and partial_bytes_acked
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* parameters based on the bytes acked in the received SACK.
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*/
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void sctp_transport_raise_cwnd(struct sctp_transport *transport,
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__u32 sack_ctsn, __u32 bytes_acked)
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{
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struct sctp_association *asoc = transport->asoc;
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__u32 cwnd, ssthresh, flight_size, pba, pmtu;
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cwnd = transport->cwnd;
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flight_size = transport->flight_size;
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/* See if we need to exit Fast Recovery first */
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if (asoc->fast_recovery &&
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TSN_lte(asoc->fast_recovery_exit, sack_ctsn))
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asoc->fast_recovery = 0;
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ssthresh = transport->ssthresh;
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pba = transport->partial_bytes_acked;
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pmtu = transport->asoc->pathmtu;
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if (cwnd <= ssthresh) {
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/* RFC 4960 7.2.1
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* o When cwnd is less than or equal to ssthresh, an SCTP
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* endpoint MUST use the slow-start algorithm to increase
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* cwnd only if the current congestion window is being fully
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* utilized, an incoming SACK advances the Cumulative TSN
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* Ack Point, and the data sender is not in Fast Recovery.
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* Only when these three conditions are met can the cwnd be
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* increased; otherwise, the cwnd MUST not be increased.
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* If these conditions are met, then cwnd MUST be increased
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* by, at most, the lesser of 1) the total size of the
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* previously outstanding DATA chunk(s) acknowledged, and
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* 2) the destination's path MTU. This upper bound protects
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* against the ACK-Splitting attack outlined in [SAVAGE99].
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*/
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if (asoc->fast_recovery)
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return;
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/* The appropriate cwnd increase algorithm is performed
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* if, and only if the congestion window is being fully
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* utilized. Note that RFC4960 Errata 3.22 removed the
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* other condition on ctsn moving.
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*/
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if (flight_size < cwnd)
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return;
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if (bytes_acked > pmtu)
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cwnd += pmtu;
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else
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cwnd += bytes_acked;
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pr_debug("%s: slow start: transport:%p, bytes_acked:%d, "
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"cwnd:%d, ssthresh:%d, flight_size:%d, pba:%d\n",
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__func__, transport, bytes_acked, cwnd, ssthresh,
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flight_size, pba);
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} else {
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/* RFC 2960 7.2.2 Whenever cwnd is greater than ssthresh,
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* upon each SACK arrival, increase partial_bytes_acked
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* by the total number of bytes of all new chunks
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* acknowledged in that SACK including chunks
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* acknowledged by the new Cumulative TSN Ack and by Gap
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* Ack Blocks. (updated by RFC4960 Errata 3.22)
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*
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* When partial_bytes_acked is greater than cwnd and
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|
* before the arrival of the SACK the sender had less
|
|
* bytes of data outstanding than cwnd (i.e., before
|
|
* arrival of the SACK, flightsize was less than cwnd),
|
|
* reset partial_bytes_acked to cwnd. (RFC 4960 Errata
|
|
* 3.26)
|
|
*
|
|
* When partial_bytes_acked is equal to or greater than
|
|
* cwnd and before the arrival of the SACK the sender
|
|
* had cwnd or more bytes of data outstanding (i.e.,
|
|
* before arrival of the SACK, flightsize was greater
|
|
* than or equal to cwnd), partial_bytes_acked is reset
|
|
* to (partial_bytes_acked - cwnd). Next, cwnd is
|
|
* increased by MTU. (RFC 4960 Errata 3.12)
|
|
*/
|
|
pba += bytes_acked;
|
|
if (pba > cwnd && flight_size < cwnd)
|
|
pba = cwnd;
|
|
if (pba >= cwnd && flight_size >= cwnd) {
|
|
pba = pba - cwnd;
|
|
cwnd += pmtu;
|
|
}
|
|
|
|
pr_debug("%s: congestion avoidance: transport:%p, "
|
|
"bytes_acked:%d, cwnd:%d, ssthresh:%d, "
|
|
"flight_size:%d, pba:%d\n", __func__,
|
|
transport, bytes_acked, cwnd, ssthresh,
|
|
flight_size, pba);
|
|
}
|
|
|
|
transport->cwnd = cwnd;
|
|
transport->partial_bytes_acked = pba;
|
|
}
|
|
|
|
/* This routine is used to lower the transport's cwnd when congestion is
|
|
* detected.
|
|
*/
|
|
void sctp_transport_lower_cwnd(struct sctp_transport *transport,
|
|
enum sctp_lower_cwnd reason)
|
|
{
|
|
struct sctp_association *asoc = transport->asoc;
|
|
|
|
switch (reason) {
|
|
case SCTP_LOWER_CWND_T3_RTX:
|
|
/* RFC 2960 Section 7.2.3, sctpimpguide
|
|
* When the T3-rtx timer expires on an address, SCTP should
|
|
* perform slow start by:
|
|
* ssthresh = max(cwnd/2, 4*MTU)
|
|
* cwnd = 1*MTU
|
|
* partial_bytes_acked = 0
|
|
*/
|
|
transport->ssthresh = max(transport->cwnd/2,
|
|
4*asoc->pathmtu);
|
|
transport->cwnd = asoc->pathmtu;
|
|
|
|
/* T3-rtx also clears fast recovery */
|
|
asoc->fast_recovery = 0;
|
|
break;
|
|
|
|
case SCTP_LOWER_CWND_FAST_RTX:
|
|
/* RFC 2960 7.2.4 Adjust the ssthresh and cwnd of the
|
|
* destination address(es) to which the missing DATA chunks
|
|
* were last sent, according to the formula described in
|
|
* Section 7.2.3.
|
|
*
|
|
* RFC 2960 7.2.3, sctpimpguide Upon detection of packet
|
|
* losses from SACK (see Section 7.2.4), An endpoint
|
|
* should do the following:
|
|
* ssthresh = max(cwnd/2, 4*MTU)
|
|
* cwnd = ssthresh
|
|
* partial_bytes_acked = 0
|
|
*/
|
|
if (asoc->fast_recovery)
|
|
return;
|
|
|
|
/* Mark Fast recovery */
|
|
asoc->fast_recovery = 1;
|
|
asoc->fast_recovery_exit = asoc->next_tsn - 1;
|
|
|
|
transport->ssthresh = max(transport->cwnd/2,
|
|
4*asoc->pathmtu);
|
|
transport->cwnd = transport->ssthresh;
|
|
break;
|
|
|
|
case SCTP_LOWER_CWND_ECNE:
|
|
/* RFC 2481 Section 6.1.2.
|
|
* If the sender receives an ECN-Echo ACK packet
|
|
* then the sender knows that congestion was encountered in the
|
|
* network on the path from the sender to the receiver. The
|
|
* indication of congestion should be treated just as a
|
|
* congestion loss in non-ECN Capable TCP. That is, the TCP
|
|
* source halves the congestion window "cwnd" and reduces the
|
|
* slow start threshold "ssthresh".
|
|
* A critical condition is that TCP does not react to
|
|
* congestion indications more than once every window of
|
|
* data (or more loosely more than once every round-trip time).
|
|
*/
|
|
if (time_after(jiffies, transport->last_time_ecne_reduced +
|
|
transport->rtt)) {
|
|
transport->ssthresh = max(transport->cwnd/2,
|
|
4*asoc->pathmtu);
|
|
transport->cwnd = transport->ssthresh;
|
|
transport->last_time_ecne_reduced = jiffies;
|
|
}
|
|
break;
|
|
|
|
case SCTP_LOWER_CWND_INACTIVE:
|
|
/* RFC 2960 Section 7.2.1, sctpimpguide
|
|
* When the endpoint does not transmit data on a given
|
|
* transport address, the cwnd of the transport address
|
|
* should be adjusted to max(cwnd/2, 4*MTU) per RTO.
|
|
* NOTE: Although the draft recommends that this check needs
|
|
* to be done every RTO interval, we do it every hearbeat
|
|
* interval.
|
|
*/
|
|
transport->cwnd = max(transport->cwnd/2,
|
|
4*asoc->pathmtu);
|
|
/* RFC 4960 Errata 3.27.2: also adjust sshthresh */
|
|
transport->ssthresh = transport->cwnd;
|
|
break;
|
|
}
|
|
|
|
transport->partial_bytes_acked = 0;
|
|
|
|
pr_debug("%s: transport:%p, reason:%d, cwnd:%d, ssthresh:%d\n",
|
|
__func__, transport, reason, transport->cwnd,
|
|
transport->ssthresh);
|
|
}
|
|
|
|
/* Apply Max.Burst limit to the congestion window:
|
|
* sctpimpguide-05 2.14.2
|
|
* D) When the time comes for the sender to
|
|
* transmit new DATA chunks, the protocol parameter Max.Burst MUST
|
|
* first be applied to limit how many new DATA chunks may be sent.
|
|
* The limit is applied by adjusting cwnd as follows:
|
|
* if ((flightsize+ Max.Burst * MTU) < cwnd)
|
|
* cwnd = flightsize + Max.Burst * MTU
|
|
*/
|
|
|
|
void sctp_transport_burst_limited(struct sctp_transport *t)
|
|
{
|
|
struct sctp_association *asoc = t->asoc;
|
|
u32 old_cwnd = t->cwnd;
|
|
u32 max_burst_bytes;
|
|
|
|
if (t->burst_limited || asoc->max_burst == 0)
|
|
return;
|
|
|
|
max_burst_bytes = t->flight_size + (asoc->max_burst * asoc->pathmtu);
|
|
if (max_burst_bytes < old_cwnd) {
|
|
t->cwnd = max_burst_bytes;
|
|
t->burst_limited = old_cwnd;
|
|
}
|
|
}
|
|
|
|
/* Restore the old cwnd congestion window, after the burst had it's
|
|
* desired effect.
|
|
*/
|
|
void sctp_transport_burst_reset(struct sctp_transport *t)
|
|
{
|
|
if (t->burst_limited) {
|
|
t->cwnd = t->burst_limited;
|
|
t->burst_limited = 0;
|
|
}
|
|
}
|
|
|
|
/* What is the next timeout value for this transport? */
|
|
unsigned long sctp_transport_timeout(struct sctp_transport *trans)
|
|
{
|
|
/* RTO + timer slack +/- 50% of RTO */
|
|
unsigned long timeout = trans->rto >> 1;
|
|
|
|
if (trans->state != SCTP_UNCONFIRMED &&
|
|
trans->state != SCTP_PF)
|
|
timeout += trans->hbinterval;
|
|
|
|
return max_t(unsigned long, timeout, HZ / 5);
|
|
}
|
|
|
|
/* Reset transport variables to their initial values */
|
|
void sctp_transport_reset(struct sctp_transport *t)
|
|
{
|
|
struct sctp_association *asoc = t->asoc;
|
|
|
|
/* RFC 2960 (bis), Section 5.2.4
|
|
* All the congestion control parameters (e.g., cwnd, ssthresh)
|
|
* related to this peer MUST be reset to their initial values
|
|
* (see Section 6.2.1)
|
|
*/
|
|
t->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
|
|
t->burst_limited = 0;
|
|
t->ssthresh = asoc->peer.i.a_rwnd;
|
|
t->rto = asoc->rto_initial;
|
|
sctp_max_rto(asoc, t);
|
|
t->rtt = 0;
|
|
t->srtt = 0;
|
|
t->rttvar = 0;
|
|
|
|
/* Reset these additional variables so that we have a clean slate. */
|
|
t->partial_bytes_acked = 0;
|
|
t->flight_size = 0;
|
|
t->error_count = 0;
|
|
t->rto_pending = 0;
|
|
t->hb_sent = 0;
|
|
|
|
/* Initialize the state information for SFR-CACC */
|
|
t->cacc.changeover_active = 0;
|
|
t->cacc.cycling_changeover = 0;
|
|
t->cacc.next_tsn_at_change = 0;
|
|
t->cacc.cacc_saw_newack = 0;
|
|
}
|
|
|
|
/* Schedule retransmission on the given transport */
|
|
void sctp_transport_immediate_rtx(struct sctp_transport *t)
|
|
{
|
|
/* Stop pending T3_rtx_timer */
|
|
if (del_timer(&t->T3_rtx_timer))
|
|
sctp_transport_put(t);
|
|
|
|
sctp_retransmit(&t->asoc->outqueue, t, SCTP_RTXR_T3_RTX);
|
|
if (!timer_pending(&t->T3_rtx_timer)) {
|
|
if (!mod_timer(&t->T3_rtx_timer, jiffies + t->rto))
|
|
sctp_transport_hold(t);
|
|
}
|
|
}
|
|
|
|
/* Drop dst */
|
|
void sctp_transport_dst_release(struct sctp_transport *t)
|
|
{
|
|
dst_release(t->dst);
|
|
t->dst = NULL;
|
|
t->dst_pending_confirm = 0;
|
|
}
|
|
|
|
/* Schedule neighbour confirm */
|
|
void sctp_transport_dst_confirm(struct sctp_transport *t)
|
|
{
|
|
t->dst_pending_confirm = 1;
|
|
}
|