v4.19.13 snapshot.
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
new file mode 100644
index 0000000..85d3930
--- /dev/null
+++ b/net/sctp/sm_sideeffect.c
@@ -0,0 +1,1829 @@
+/* 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>
+#include <net/sctp/stream_sched.h>
+
+static int sctp_cmd_interpreter(enum sctp_event event_type,
+ union sctp_subtype subtype,
+ enum sctp_state state,
+ struct sctp_endpoint *ep,
+ struct sctp_association *asoc,
+ void *event_arg,
+ enum sctp_disposition status,
+ struct sctp_cmd_seq *commands,
+ gfp_t gfp);
+static int sctp_side_effects(enum sctp_event event_type,
+ union sctp_subtype subtype,
+ enum sctp_state state,
+ struct sctp_endpoint *ep,
+ struct sctp_association **asoc,
+ void *event_arg,
+ enum sctp_disposition status,
+ struct sctp_cmd_seq *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;
+}
+
+/* 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,
+ struct sctp_cmd_seq *commands)
+{
+ struct sctp_transport *trans = asoc->peer.last_data_from;
+ __u32 ctsn, max_tsn_seen;
+ struct sctp_chunk *sack;
+ int error = 0;
+
+ if (force ||
+ (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) ||
+ (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE)))
+ asoc->peer.sack_needed = 1;
+
+ ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
+ max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map);
+
+ /* From 12.2 Parameters necessary per association (i.e. the TCB):
+ *
+ * Ack State : This flag indicates if the next received packet
+ * : is to be responded to with a SACK. ...
+ * : When DATA chunks are out of order, SACK's
+ * : are not delayed (see Section 6).
+ *
+ * [This is actually not mentioned in Section 6, but we
+ * implement it here anyway. --piggy]
+ */
+ if (max_tsn_seen != ctsn)
+ asoc->peer.sack_needed = 1;
+
+ /* From 6.2 Acknowledgement on Reception of DATA Chunks:
+ *
+ * Section 4.2 of [RFC2581] SHOULD be followed. Specifically,
+ * an acknowledgement SHOULD be generated for at least every
+ * second packet (not every second DATA chunk) received, and
+ * SHOULD be generated within 200 ms of the arrival of any
+ * unacknowledged DATA chunk. ...
+ */
+ if (!asoc->peer.sack_needed) {
+ asoc->peer.sack_cnt++;
+
+ /* Set the SACK delay timeout based on the
+ * SACK delay for the last transport
+ * data was received from, or the default
+ * for the association.
+ */
+ if (trans) {
+ /* We will need a SACK for the next packet. */
+ if (asoc->peer.sack_cnt >= trans->sackfreq - 1)
+ asoc->peer.sack_needed = 1;
+
+ asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
+ trans->sackdelay;
+ } else {
+ /* We will need a SACK for the next packet. */
+ if (asoc->peer.sack_cnt >= asoc->sackfreq - 1)
+ asoc->peer.sack_needed = 1;
+
+ asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] =
+ asoc->sackdelay;
+ }
+
+ /* Restart the SACK timer. */
+ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
+ SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
+ } else {
+ __u32 old_a_rwnd = asoc->a_rwnd;
+
+ asoc->a_rwnd = asoc->rwnd;
+ sack = sctp_make_sack(asoc);
+ if (!sack) {
+ asoc->a_rwnd = old_a_rwnd;
+ goto nomem;
+ }
+
+ asoc->peer.sack_needed = 0;
+ asoc->peer.sack_cnt = 0;
+
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack));
+
+ /* Stop the SACK timer. */
+ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
+ SCTP_TO(SCTP_EVENT_TIMEOUT_SACK));
+ }
+
+ return error;
+nomem:
+ error = -ENOMEM;
+ return error;
+}
+
+/* When the T3-RTX timer expires, it calls this function to create the
+ * relevant state machine event.
+ */
+void sctp_generate_t3_rtx_event(struct timer_list *t)
+{
+ struct sctp_transport *transport =
+ from_timer(transport, t, T3_rtx_timer);
+ struct sctp_association *asoc = transport->asoc;
+ struct sock *sk = asoc->base.sk;
+ struct net *net = sock_net(sk);
+ int error;
+
+ /* Check whether a task is in the sock. */
+
+ bh_lock_sock(sk);
+ if (sock_owned_by_user(sk)) {
+ pr_debug("%s: sock is busy\n", __func__);
+
+ /* Try again later. */
+ if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20)))
+ sctp_transport_hold(transport);
+ goto out_unlock;
+ }
+
+ /* Run through the state machine. */
+ error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
+ SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX),
+ asoc->state,
+ asoc->ep, asoc,
+ transport, GFP_ATOMIC);
+
+ if (error)
+ sk->sk_err = -error;
+
+out_unlock:
+ bh_unlock_sock(sk);
+ sctp_transport_put(transport);
+}
+
+/* This is a sa interface for producing timeout events. It works
+ * for timeouts which use the association as their parameter.
+ */
+static void sctp_generate_timeout_event(struct sctp_association *asoc,
+ enum sctp_event_timeout timeout_type)
+{
+ struct sock *sk = asoc->base.sk;
+ struct net *net = sock_net(sk);
+ int error = 0;
+
+ bh_lock_sock(sk);
+ if (sock_owned_by_user(sk)) {
+ pr_debug("%s: sock is busy: timer %d\n", __func__,
+ timeout_type);
+
+ /* Try again later. */
+ if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20)))
+ sctp_association_hold(asoc);
+ goto out_unlock;
+ }
+
+ /* Is this association really dead and just waiting around for
+ * the timer to let go of the reference?
+ */
+ if (asoc->base.dead)
+ goto out_unlock;
+
+ /* Run through the state machine. */
+ error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
+ SCTP_ST_TIMEOUT(timeout_type),
+ asoc->state, asoc->ep, asoc,
+ (void *)timeout_type, GFP_ATOMIC);
+
+ if (error)
+ sk->sk_err = -error;
+
+out_unlock:
+ bh_unlock_sock(sk);
+ sctp_association_put(asoc);
+}
+
+static void sctp_generate_t1_cookie_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_COOKIE]);
+
+ sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE);
+}
+
+static void sctp_generate_t1_init_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T1_INIT]);
+
+ sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT);
+}
+
+static void sctp_generate_t2_shutdown_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN]);
+
+ sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN);
+}
+
+static void sctp_generate_t4_rto_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_T4_RTO]);
+
+ sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO);
+}
+
+static void sctp_generate_t5_shutdown_guard_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t,
+ timers[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]);
+
+ sctp_generate_timeout_event(asoc,
+ SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD);
+
+} /* sctp_generate_t5_shutdown_guard_event() */
+
+static void sctp_generate_autoclose_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_AUTOCLOSE]);
+
+ 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(struct timer_list *t)
+{
+ struct sctp_transport *transport = from_timer(transport, t, hb_timer);
+ struct sctp_association *asoc = transport->asoc;
+ struct sock *sk = asoc->base.sk;
+ struct net *net = sock_net(sk);
+ u32 elapsed, timeout;
+ 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->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);
+}
+
+/* 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(struct timer_list *t)
+{
+ struct sctp_transport *transport =
+ from_timer(transport, t, proto_unreach_timer);
+ 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);
+}
+
+ /* Handle the timeout of the RE-CONFIG timer. */
+void sctp_generate_reconf_event(struct timer_list *t)
+{
+ struct sctp_transport *transport =
+ from_timer(transport, t, reconf_timer);
+ 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);
+}
+
+/* Inject a SACK Timeout event into the state machine. */
+static void sctp_generate_sack_event(struct timer_list *t)
+{
+ struct sctp_association *asoc =
+ from_timer(asoc, t, timers[SCTP_EVENT_TIMEOUT_SACK]);
+
+ sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK);
+}
+
+sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
+ [SCTP_EVENT_TIMEOUT_NONE] = NULL,
+ [SCTP_EVENT_TIMEOUT_T1_COOKIE] = sctp_generate_t1_cookie_event,
+ [SCTP_EVENT_TIMEOUT_T1_INIT] = sctp_generate_t1_init_event,
+ [SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = sctp_generate_t2_shutdown_event,
+ [SCTP_EVENT_TIMEOUT_T3_RTX] = NULL,
+ [SCTP_EVENT_TIMEOUT_T4_RTO] = sctp_generate_t4_rto_event,
+ [SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD] =
+ sctp_generate_t5_shutdown_guard_event,
+ [SCTP_EVENT_TIMEOUT_HEARTBEAT] = NULL,
+ [SCTP_EVENT_TIMEOUT_RECONF] = NULL,
+ [SCTP_EVENT_TIMEOUT_SACK] = sctp_generate_sack_event,
+ [SCTP_EVENT_TIMEOUT_AUTOCLOSE] = 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(struct sctp_cmd_seq *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);
+ }
+}
+
+/* Worker routine to handle INIT command failure. */
+static void sctp_cmd_init_failed(struct sctp_cmd_seq *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(struct sctp_cmd_seq *commands,
+ struct sctp_association *asoc,
+ enum sctp_event event_type,
+ union sctp_subtype subtype,
+ struct sctp_chunk *chunk,
+ unsigned int error)
+{
+ struct sctp_ulpevent *event;
+ struct sctp_chunk *abort;
+
+ /* Cancel any partial delivery in progress. */
+ asoc->stream.si->abort_pd(&asoc->ulpq, GFP_ATOMIC);
+
+ if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
+ event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
+ (__u16)error, 0, 0, chunk,
+ GFP_ATOMIC);
+ else
+ event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
+ (__u16)error, 0, 0, NULL,
+ GFP_ATOMIC);
+ if (event)
+ sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
+ SCTP_ULPEVENT(event));
+
+ if (asoc->overall_error_count >= asoc->max_retrans) {
+ abort = sctp_make_violation_max_retrans(asoc, chunk);
+ if (abort)
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(abort));
+ }
+
+ sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
+ SCTP_STATE(SCTP_STATE_CLOSED));
+
+ /* SEND_FAILED sent later when cleaning up the association. */
+ asoc->outqueue.error = error;
+ sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
+}
+
+/* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT
+ * inside the cookie. In reality, this is only used for INIT-ACK processing
+ * since all other cases use "temporary" associations and can do all
+ * their work in statefuns directly.
+ */
+static int sctp_cmd_process_init(struct sctp_cmd_seq *commands,
+ struct sctp_association *asoc,
+ struct sctp_chunk *chunk,
+ struct sctp_init_chunk *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(struct sctp_cmd_seq *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);
+}
+
+static void sctp_cmd_hb_timers_stop(struct sctp_cmd_seq *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(struct sctp_cmd_seq *cmds,
+ struct sctp_association *asoc)
+{
+ struct sctp_transport *t;
+
+ list_for_each_entry(t, &asoc->peer.transport_addr_list,
+ transports) {
+ if (del_timer(&t->T3_rtx_timer))
+ sctp_transport_put(t);
+ }
+}
+
+
+/* Helper function to handle the reception of an HEARTBEAT ACK. */
+static void sctp_cmd_transport_on(struct sctp_cmd_seq *cmds,
+ struct sctp_association *asoc,
+ struct sctp_transport *t,
+ struct sctp_chunk *chunk)
+{
+ struct sctp_sender_hb_info *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 = (struct sctp_sender_hb_info *)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);
+}
+
+
+/* Helper function to process the process SACK command. */
+static int sctp_cmd_process_sack(struct sctp_cmd_seq *cmds,
+ struct sctp_association *asoc,
+ struct sctp_chunk *chunk)
+{
+ int err = 0;
+
+ if (sctp_outq_sack(&asoc->outqueue, chunk)) {
+ struct net *net = sock_net(asoc->base.sk);
+
+ /* There are no more TSNs awaiting SACK. */
+ err = sctp_do_sm(net, SCTP_EVENT_T_OTHER,
+ SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN),
+ asoc->state, asoc->ep, asoc, NULL,
+ GFP_ATOMIC);
+ }
+
+ return err;
+}
+
+/* Helper function to set the timeout value for T2-SHUTDOWN timer and to set
+ * the transport for a shutdown chunk.
+ */
+static void sctp_cmd_setup_t2(struct sctp_cmd_seq *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;
+}
+
+static void sctp_cmd_assoc_update(struct sctp_cmd_seq *cmds,
+ struct sctp_association *asoc,
+ struct sctp_association *new)
+{
+ struct net *net = sock_net(asoc->base.sk);
+ struct sctp_chunk *abort;
+
+ if (!sctp_assoc_update(asoc, new))
+ return;
+
+ abort = sctp_make_abort(asoc, NULL, sizeof(struct sctp_errhdr));
+ if (abort) {
+ sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0);
+ sctp_add_cmd_sf(cmds, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
+ }
+ sctp_add_cmd_sf(cmds, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNABORTED));
+ sctp_add_cmd_sf(cmds, SCTP_CMD_ASSOC_FAILED,
+ SCTP_PERR(SCTP_ERROR_RSRC_LOW));
+ SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
+ SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
+}
+
+/* Helper function to change the state of an association. */
+static void sctp_cmd_new_state(struct sctp_cmd_seq *cmds,
+ struct sctp_association *asoc,
+ enum sctp_state 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))
+ inet_sk_set_state(sk, SCTP_SS_ESTABLISHED);
+
+ /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
+ if (sctp_state(asoc, SHUTDOWN_RECEIVED) &&
+ sctp_sstate(sk, ESTABLISHED)) {
+ inet_sk_set_state(sk, 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->sk_state_change(sk);
+ }
+
+ if (sctp_state(asoc, SHUTDOWN_PENDING) &&
+ !sctp_outq_is_empty(&asoc->outqueue))
+ sctp_outq_uncork(&asoc->outqueue, GFP_ATOMIC);
+}
+
+/* Helper function to delete an association. */
+static void sctp_cmd_delete_tcb(struct sctp_cmd_seq *cmds,
+ struct sctp_association *asoc)
+{
+ struct sock *sk = asoc->base.sk;
+
+ /* If it is a non-temporary association belonging to a TCP-style
+ * listening socket that is not closed, do not free it so that accept()
+ * can pick it up later.
+ */
+ if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) &&
+ (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK))
+ return;
+
+ sctp_association_free(asoc);
+}
+
+/*
+ * ADDIP Section 4.1 ASCONF Chunk Procedures
+ * A4) Start a T-4 RTO timer, using the RTO value of the selected
+ * destination address (we use active path instead of primary path just
+ * because primary path may be inactive.
+ */
+static void sctp_cmd_setup_t4(struct sctp_cmd_seq *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(struct sctp_cmd_seq *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;
+
+ asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+
+ switch (err_hdr->cause) {
+ case SCTP_ERROR_UNKNOWN_CHUNK:
+ {
+ struct sctp_chunkhdr *unk_chunk_hdr;
+
+ unk_chunk_hdr = (struct sctp_chunkhdr *)
+ 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;
+ }
+ }
+}
+
+/* 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 *temp;
+ struct list_head *pos;
+
+ list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
+ t = list_entry(pos, struct sctp_transport, transports);
+ if (!sctp_cmp_addr_exact(&t->ipaddr,
+ &asoc->peer.primary_addr)) {
+ sctp_assoc_rm_peer(asoc, t);
+ }
+ }
+}
+
+/* Helper function to set sk_err on a 1-1 style socket. */
+static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error)
+{
+ struct sock *sk = asoc->base.sk;
+
+ if (!sctp_style(sk, UDP))
+ sk->sk_err = error;
+}
+
+/* Helper function to generate an association change event */
+static void sctp_cmd_assoc_change(struct sctp_cmd_seq *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)
+ asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+}
+
+static void sctp_cmd_peer_no_auth(struct sctp_cmd_seq *commands,
+ struct sctp_association *asoc)
+{
+ struct sctp_ulpevent *ev;
+
+ ev = sctp_ulpevent_make_authkey(asoc, 0, SCTP_AUTH_NO_AUTH, GFP_ATOMIC);
+ if (ev)
+ asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+}
+
+/* Helper function to generate an adaptation indication event */
+static void sctp_cmd_adaptation_ind(struct sctp_cmd_seq *commands,
+ struct sctp_association *asoc)
+{
+ struct sctp_ulpevent *ev;
+
+ ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC);
+
+ if (ev)
+ asoc->stream.si->enqueue_event(&asoc->ulpq, ev);
+}
+
+
+static void sctp_cmd_t1_timer_update(struct sctp_association *asoc,
+ enum sctp_event_timeout timer,
+ char *name)
+{
+ struct sctp_transport *t;
+
+ t = asoc->init_last_sent_to;
+ asoc->init_err_counter++;
+
+ if (t->init_sent_count > (asoc->init_cycle + 1)) {
+ asoc->timeouts[timer] *= 2;
+ if (asoc->timeouts[timer] > asoc->max_init_timeo) {
+ asoc->timeouts[timer] = asoc->max_init_timeo;
+ }
+ asoc->init_cycle++;
+
+ pr_debug("%s: T1[%s] timeout adjustment init_err_counter:%d"
+ " cycle:%d timeout:%ld\n", __func__, name,
+ asoc->init_err_counter, asoc->init_cycle,
+ asoc->timeouts[timer]);
+ }
+
+}
+
+/* Send the whole message, chunk by chunk, to the outqueue.
+ * This way the whole message is queued up and bundling if
+ * encouraged for small fragments.
+ */
+static void sctp_cmd_send_msg(struct sctp_association *asoc,
+ struct sctp_datamsg *msg, gfp_t gfp)
+{
+ struct sctp_chunk *chunk;
+
+ list_for_each_entry(chunk, &msg->chunks, frag_list)
+ sctp_outq_tail(&asoc->outqueue, chunk, gfp);
+
+ asoc->outqueue.sched->enqueue(&asoc->outqueue, msg);
+}
+
+
+/* Sent the next ASCONF packet currently stored in the association.
+ * This happens after the ASCONF_ACK was succeffully processed.
+ */
+static void sctp_cmd_send_asconf(struct sctp_association *asoc)
+{
+ struct net *net = sock_net(asoc->base.sk);
+
+ /* Send the next asconf chunk from the addip chunk
+ * queue.
+ */
+ if (!list_empty(&asoc->addip_chunk_list)) {
+ struct list_head *entry = asoc->addip_chunk_list.next;
+ struct sctp_chunk *asconf = list_entry(entry,
+ struct sctp_chunk, list);
+ list_del_init(entry);
+
+ /* Hold the chunk until an ASCONF_ACK is received. */
+ sctp_chunk_hold(asconf);
+ if (sctp_primitive_ASCONF(net, asoc, asconf))
+ sctp_chunk_free(asconf);
+ else
+ asoc->addip_last_asconf = asconf;
+ }
+}
+
+
+/* These three macros allow us to pull the debugging code out of the
+ * main flow of sctp_do_sm() to keep attention focused on the real
+ * functionality there.
+ */
+#define debug_pre_sfn() \
+ pr_debug("%s[pre-fn]: ep:%p, %s, %s, asoc:%p[%s], %s\n", __func__, \
+ ep, sctp_evttype_tbl[event_type], (*debug_fn)(subtype), \
+ asoc, sctp_state_tbl[state], state_fn->name)
+
+#define debug_post_sfn() \
+ pr_debug("%s[post-fn]: asoc:%p, status:%s\n", __func__, asoc, \
+ sctp_status_tbl[status])
+
+#define debug_post_sfx() \
+ pr_debug("%s[post-sfx]: error:%d, asoc:%p[%s]\n", __func__, error, \
+ asoc, sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \
+ sctp_assoc2id(asoc))) ? asoc->state : SCTP_STATE_CLOSED])
+
+/*
+ * This is the master state machine processing function.
+ *
+ * If you want to understand all of lksctp, this is a
+ * good place to start.
+ */
+int sctp_do_sm(struct net *net, enum sctp_event event_type,
+ union sctp_subtype subtype, enum sctp_state state,
+ struct sctp_endpoint *ep, struct sctp_association *asoc,
+ void *event_arg, gfp_t gfp)
+{
+ typedef const char *(printfn_t)(union sctp_subtype);
+ static printfn_t *table[] = {
+ NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname,
+ };
+ printfn_t *debug_fn __attribute__ ((unused)) = table[event_type];
+ const struct sctp_sm_table_entry *state_fn;
+ struct sctp_cmd_seq commands;
+ enum sctp_disposition status;
+ int error = 0;
+
+ /* Look up the state function, run it, and then process the
+ * side effects. These three steps are the heart of lksctp.
+ */
+ state_fn = sctp_sm_lookup_event(net, event_type, state, subtype);
+
+ sctp_init_cmd_seq(&commands);
+
+ debug_pre_sfn();
+ status = state_fn->fn(net, ep, asoc, subtype, event_arg, &commands);
+ debug_post_sfn();
+
+ error = sctp_side_effects(event_type, subtype, state,
+ ep, &asoc, event_arg, status,
+ &commands, gfp);
+ debug_post_sfx();
+
+ return error;
+}
+
+/*****************************************************************
+ * This the master state function side effect processing function.
+ *****************************************************************/
+static int sctp_side_effects(enum sctp_event event_type,
+ union sctp_subtype subtype,
+ enum sctp_state state,
+ struct sctp_endpoint *ep,
+ struct sctp_association **asoc,
+ void *event_arg,
+ enum sctp_disposition status,
+ struct sctp_cmd_seq *commands,
+ gfp_t gfp)
+{
+ int error;
+
+ /* FIXME - Most of the dispositions left today would be categorized
+ * as "exceptional" dispositions. For those dispositions, it
+ * may not be proper to run through any of the commands at all.
+ * For example, the command interpreter might be run only with
+ * disposition SCTP_DISPOSITION_CONSUME.
+ */
+ if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state,
+ ep, *asoc,
+ event_arg, status,
+ commands, gfp)))
+ goto bail;
+
+ switch (status) {
+ case SCTP_DISPOSITION_DISCARD:
+ pr_debug("%s: ignored sctp protocol event - state:%d, "
+ "event_type:%d, event_id:%d\n", __func__, state,
+ event_type, subtype.chunk);
+ break;
+
+ case SCTP_DISPOSITION_NOMEM:
+ /* We ran out of memory, so we need to discard this
+ * packet.
+ */
+ /* BUG--we should now recover some memory, probably by
+ * reneging...
+ */
+ error = -ENOMEM;
+ break;
+
+ case SCTP_DISPOSITION_DELETE_TCB:
+ case SCTP_DISPOSITION_ABORT:
+ /* This should now be a command. */
+ *asoc = NULL;
+ break;
+
+ case SCTP_DISPOSITION_CONSUME:
+ /*
+ * We should no longer have much work to do here as the
+ * real work has been done as explicit commands above.
+ */
+ break;
+
+ case SCTP_DISPOSITION_VIOLATION:
+ net_err_ratelimited("protocol violation state %d chunkid %d\n",
+ state, subtype.chunk);
+ break;
+
+ case SCTP_DISPOSITION_NOT_IMPL:
+ pr_warn("unimplemented feature in state %d, event_type %d, event_id %d\n",
+ state, event_type, subtype.chunk);
+ break;
+
+ case SCTP_DISPOSITION_BUG:
+ pr_err("bug in state %d, event_type %d, event_id %d\n",
+ state, event_type, subtype.chunk);
+ BUG();
+ break;
+
+ default:
+ pr_err("impossible disposition %d in state %d, event_type %d, event_id %d\n",
+ status, state, event_type, subtype.chunk);
+ BUG();
+ break;
+ }
+
+bail:
+ return error;
+}
+
+/********************************************************************
+ * 2nd Level Abstractions
+ ********************************************************************/
+
+/* This is the side-effect interpreter. */
+static int sctp_cmd_interpreter(enum sctp_event event_type,
+ union sctp_subtype subtype,
+ enum sctp_state state,
+ struct sctp_endpoint *ep,
+ struct sctp_association *asoc,
+ void *event_arg,
+ enum sctp_disposition status,
+ struct sctp_cmd_seq *commands,
+ gfp_t gfp)
+{
+ struct sctp_sock *sp = sctp_sk(ep->base.sk);
+ struct sctp_chunk *chunk = NULL, *new_obj;
+ struct sctp_packet *packet;
+ struct sctp_sackhdr sackh;
+ struct timer_list *timer;
+ struct sctp_transport *t;
+ unsigned long timeout;
+ struct sctp_cmd *cmd;
+ int local_cork = 0;
+ int error = 0;
+ int force;
+
+ if (SCTP_EVENT_T_TIMEOUT != event_type)
+ chunk = event_arg;
+
+ /* Note: This whole file is a huge candidate for rework.
+ * For example, each command could either have its own handler, so
+ * the loop would look like:
+ * while (cmds)
+ * cmd->handle(x, y, z)
+ * --jgrimm
+ */
+ while (NULL != (cmd = sctp_next_cmd(commands))) {
+ switch (cmd->verb) {
+ case SCTP_CMD_NOP:
+ /* Do nothing. */
+ break;
+
+ case SCTP_CMD_NEW_ASOC:
+ /* Register a new association. */
+ if (local_cork) {
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+ local_cork = 0;
+ }
+
+ /* Register with the endpoint. */
+ asoc = cmd->obj.asoc;
+ BUG_ON(asoc->peer.primary_path == NULL);
+ sctp_endpoint_add_asoc(ep, asoc);
+ break;
+
+ case SCTP_CMD_UPDATE_ASSOC:
+ sctp_cmd_assoc_update(commands, asoc, cmd->obj.asoc);
+ break;
+
+ case SCTP_CMD_PURGE_OUTQUEUE:
+ sctp_outq_teardown(&asoc->outqueue);
+ break;
+
+ case SCTP_CMD_DELETE_TCB:
+ if (local_cork) {
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+ local_cork = 0;
+ }
+ /* Delete the current association. */
+ sctp_cmd_delete_tcb(commands, asoc);
+ asoc = NULL;
+ break;
+
+ case SCTP_CMD_NEW_STATE:
+ /* Enter a new state. */
+ sctp_cmd_new_state(commands, asoc, cmd->obj.state);
+ break;
+
+ case SCTP_CMD_REPORT_TSN:
+ /* Record the arrival of a TSN. */
+ error = sctp_tsnmap_mark(&asoc->peer.tsn_map,
+ cmd->obj.u32, NULL);
+ break;
+
+ case SCTP_CMD_REPORT_FWDTSN:
+ asoc->stream.si->report_ftsn(&asoc->ulpq, cmd->obj.u32);
+ break;
+
+ case SCTP_CMD_PROCESS_FWDTSN:
+ asoc->stream.si->handle_ftsn(&asoc->ulpq,
+ cmd->obj.chunk);
+ break;
+
+ case SCTP_CMD_GEN_SACK:
+ /* Generate a Selective ACK.
+ * The argument tells us whether to just count
+ * the packet and MAYBE generate a SACK, or
+ * force a SACK out.
+ */
+ force = cmd->obj.i32;
+ error = sctp_gen_sack(asoc, force, commands);
+ break;
+
+ case SCTP_CMD_PROCESS_SACK:
+ /* Process an inbound SACK. */
+ error = sctp_cmd_process_sack(commands, asoc,
+ cmd->obj.chunk);
+ break;
+
+ case SCTP_CMD_GEN_INIT_ACK:
+ /* Generate an INIT ACK chunk. */
+ new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,
+ 0);
+ if (!new_obj)
+ goto nomem;
+
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(new_obj));
+ break;
+
+ case SCTP_CMD_PEER_INIT:
+ /* Process a unified INIT from the peer.
+ * Note: Only used during INIT-ACK processing. If
+ * there is an error just return to the outter
+ * layer which will bail.
+ */
+ error = sctp_cmd_process_init(commands, asoc, chunk,
+ cmd->obj.init, gfp);
+ break;
+
+ case SCTP_CMD_GEN_COOKIE_ECHO:
+ /* Generate a COOKIE ECHO chunk. */
+ new_obj = sctp_make_cookie_echo(asoc, chunk);
+ if (!new_obj) {
+ if (cmd->obj.chunk)
+ sctp_chunk_free(cmd->obj.chunk);
+ goto nomem;
+ }
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(new_obj));
+
+ /* If there is an ERROR chunk to be sent along with
+ * the COOKIE_ECHO, send it, too.
+ */
+ if (cmd->obj.chunk)
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(cmd->obj.chunk));
+
+ if (new_obj->transport) {
+ new_obj->transport->init_sent_count++;
+ asoc->init_last_sent_to = new_obj->transport;
+ }
+
+ /* FIXME - Eventually come up with a cleaner way to
+ * enabling COOKIE-ECHO + DATA bundling during
+ * multihoming stale cookie scenarios, the following
+ * command plays with asoc->peer.retran_path to
+ * avoid the problem of sending the COOKIE-ECHO and
+ * DATA in different paths, which could result
+ * in the association being ABORTed if the DATA chunk
+ * is processed first by the server. Checking the
+ * init error counter simply causes this command
+ * to be executed only during failed attempts of
+ * association establishment.
+ */
+ if ((asoc->peer.retran_path !=
+ asoc->peer.primary_path) &&
+ (asoc->init_err_counter > 0)) {
+ sctp_add_cmd_sf(commands,
+ SCTP_CMD_FORCE_PRIM_RETRAN,
+ SCTP_NULL());
+ }
+
+ break;
+
+ case SCTP_CMD_GEN_SHUTDOWN:
+ /* Generate SHUTDOWN when in SHUTDOWN_SENT state.
+ * Reset error counts.
+ */
+ asoc->overall_error_count = 0;
+
+ /* Generate a SHUTDOWN chunk. */
+ new_obj = sctp_make_shutdown(asoc, chunk);
+ if (!new_obj)
+ goto nomem;
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(new_obj));
+ break;
+
+ case SCTP_CMD_CHUNK_ULP:
+ /* Send a chunk to the sockets layer. */
+ pr_debug("%s: sm_sideff: chunk_up:%p, ulpq:%p\n",
+ __func__, cmd->obj.chunk, &asoc->ulpq);
+
+ asoc->stream.si->ulpevent_data(&asoc->ulpq,
+ cmd->obj.chunk,
+ GFP_ATOMIC);
+ break;
+
+ case SCTP_CMD_EVENT_ULP:
+ /* Send a notification to the sockets layer. */
+ pr_debug("%s: sm_sideff: event_up:%p, ulpq:%p\n",
+ __func__, cmd->obj.ulpevent, &asoc->ulpq);
+
+ asoc->stream.si->enqueue_event(&asoc->ulpq,
+ cmd->obj.ulpevent);
+ break;
+
+ case SCTP_CMD_REPLY:
+ /* If an caller has not already corked, do cork. */
+ if (!asoc->outqueue.cork) {
+ sctp_outq_cork(&asoc->outqueue);
+ local_cork = 1;
+ }
+ /* Send a chunk to our peer. */
+ sctp_outq_tail(&asoc->outqueue, cmd->obj.chunk, gfp);
+ break;
+
+ case SCTP_CMD_SEND_PKT:
+ /* Send a full packet to our peer. */
+ packet = cmd->obj.packet;
+ sctp_packet_transmit(packet, gfp);
+ sctp_ootb_pkt_free(packet);
+ break;
+
+ case SCTP_CMD_T1_RETRAN:
+ /* Mark a transport for retransmission. */
+ sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
+ SCTP_RTXR_T1_RTX);
+ break;
+
+ case SCTP_CMD_RETRAN:
+ /* Mark a transport for retransmission. */
+ sctp_retransmit(&asoc->outqueue, cmd->obj.transport,
+ SCTP_RTXR_T3_RTX);
+ break;
+
+ case SCTP_CMD_ECN_CE:
+ /* Do delayed CE processing. */
+ sctp_do_ecn_ce_work(asoc, cmd->obj.u32);
+ break;
+
+ case SCTP_CMD_ECN_ECNE:
+ /* Do delayed ECNE processing. */
+ new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32,
+ chunk);
+ if (new_obj)
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(new_obj));
+ break;
+
+ case SCTP_CMD_ECN_CWR:
+ /* Do delayed CWR processing. */
+ sctp_do_ecn_cwr_work(asoc, cmd->obj.u32);
+ break;
+
+ case SCTP_CMD_SETUP_T2:
+ sctp_cmd_setup_t2(commands, asoc, cmd->obj.chunk);
+ break;
+
+ case SCTP_CMD_TIMER_START_ONCE:
+ timer = &asoc->timers[cmd->obj.to];
+
+ if (timer_pending(timer))
+ break;
+ /* fall through */
+
+ case SCTP_CMD_TIMER_START:
+ timer = &asoc->timers[cmd->obj.to];
+ timeout = asoc->timeouts[cmd->obj.to];
+ BUG_ON(!timeout);
+
+ timer->expires = jiffies + timeout;
+ sctp_association_hold(asoc);
+ add_timer(timer);
+ break;
+
+ case SCTP_CMD_TIMER_RESTART:
+ timer = &asoc->timers[cmd->obj.to];
+ timeout = asoc->timeouts[cmd->obj.to];
+ if (!mod_timer(timer, jiffies + timeout))
+ sctp_association_hold(asoc);
+ break;
+
+ case SCTP_CMD_TIMER_STOP:
+ timer = &asoc->timers[cmd->obj.to];
+ if (del_timer(timer))
+ sctp_association_put(asoc);
+ break;
+
+ case SCTP_CMD_INIT_CHOOSE_TRANSPORT:
+ chunk = cmd->obj.chunk;
+ t = sctp_assoc_choose_alter_transport(asoc,
+ asoc->init_last_sent_to);
+ asoc->init_last_sent_to = t;
+ chunk->transport = t;
+ t->init_sent_count++;
+ /* Set the new transport as primary */
+ sctp_assoc_set_primary(asoc, t);
+ break;
+
+ case SCTP_CMD_INIT_RESTART:
+ /* Do the needed accounting and updates
+ * associated with restarting an initialization
+ * timer. Only multiply the timeout by two if
+ * all transports have been tried at the current
+ * timeout.
+ */
+ sctp_cmd_t1_timer_update(asoc,
+ SCTP_EVENT_TIMEOUT_T1_INIT,
+ "INIT");
+
+ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
+ SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
+ break;
+
+ case SCTP_CMD_COOKIEECHO_RESTART:
+ /* Do the needed accounting and updates
+ * associated with restarting an initialization
+ * timer. Only multiply the timeout by two if
+ * all transports have been tried at the current
+ * timeout.
+ */
+ sctp_cmd_t1_timer_update(asoc,
+ SCTP_EVENT_TIMEOUT_T1_COOKIE,
+ "COOKIE");
+
+ /* If we've sent any data bundled with
+ * COOKIE-ECHO we need to resend.
+ */
+ list_for_each_entry(t, &asoc->peer.transport_addr_list,
+ transports) {
+ sctp_retransmit_mark(&asoc->outqueue, t,
+ SCTP_RTXR_T1_RTX);
+ }
+
+ sctp_add_cmd_sf(commands,
+ SCTP_CMD_TIMER_RESTART,
+ SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE));
+ break;
+
+ case SCTP_CMD_INIT_FAILED:
+ sctp_cmd_init_failed(commands, asoc, cmd->obj.u32);
+ break;
+
+ case SCTP_CMD_ASSOC_FAILED:
+ sctp_cmd_assoc_failed(commands, asoc, event_type,
+ subtype, chunk, cmd->obj.u32);
+ break;
+
+ case SCTP_CMD_INIT_COUNTER_INC:
+ asoc->init_err_counter++;
+ break;
+
+ case SCTP_CMD_INIT_COUNTER_RESET:
+ asoc->init_err_counter = 0;
+ asoc->init_cycle = 0;
+ list_for_each_entry(t, &asoc->peer.transport_addr_list,
+ transports) {
+ t->init_sent_count = 0;
+ }
+ break;
+
+ case SCTP_CMD_REPORT_DUP:
+ sctp_tsnmap_mark_dup(&asoc->peer.tsn_map,
+ cmd->obj.u32);
+ break;
+
+ case SCTP_CMD_REPORT_BAD_TAG:
+ pr_debug("%s: vtag mismatch!\n", __func__);
+ break;
+
+ case SCTP_CMD_STRIKE:
+ /* Mark one strike against a transport. */
+ sctp_do_8_2_transport_strike(commands, asoc,
+ cmd->obj.transport, 0);
+ break;
+
+ case SCTP_CMD_TRANSPORT_IDLE:
+ t = cmd->obj.transport;
+ sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE);
+ break;
+
+ case SCTP_CMD_TRANSPORT_HB_SENT:
+ t = cmd->obj.transport;
+ sctp_do_8_2_transport_strike(commands, asoc,
+ t, 1);
+ t->hb_sent = 1;
+ break;
+
+ case SCTP_CMD_TRANSPORT_ON:
+ t = cmd->obj.transport;
+ sctp_cmd_transport_on(commands, asoc, t, chunk);
+ break;
+
+ case SCTP_CMD_HB_TIMERS_START:
+ sctp_cmd_hb_timers_start(commands, asoc);
+ break;
+
+ case SCTP_CMD_HB_TIMER_UPDATE:
+ t = cmd->obj.transport;
+ sctp_transport_reset_hb_timer(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 = htonl(asoc->peer.rwnd +
+ asoc->outqueue.outstanding_bytes);
+ sackh.num_gap_ack_blocks = 0;
+ sackh.num_dup_tsns = 0;
+ chunk->subh.sack_hdr = &sackh;
+ sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK,
+ SCTP_CHUNK(chunk));
+ break;
+
+ case SCTP_CMD_DISCARD_PACKET:
+ /* We need to discard the whole packet.
+ * Uncork the queue since there might be
+ * responses pending
+ */
+ chunk->pdiscard = 1;
+ if (asoc) {
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+ local_cork = 0;
+ }
+ break;
+
+ case SCTP_CMD_RTO_PENDING:
+ t = cmd->obj.transport;
+ t->rto_pending = 1;
+ break;
+
+ case SCTP_CMD_PART_DELIVER:
+ asoc->stream.si->start_pd(&asoc->ulpq, GFP_ATOMIC);
+ break;
+
+ case SCTP_CMD_RENEGE:
+ asoc->stream.si->renege_events(&asoc->ulpq,
+ cmd->obj.chunk,
+ GFP_ATOMIC);
+ break;
+
+ case SCTP_CMD_SETUP_T4:
+ sctp_cmd_setup_t4(commands, asoc, cmd->obj.chunk);
+ break;
+
+ case SCTP_CMD_PROCESS_OPERR:
+ sctp_cmd_process_operr(commands, asoc, chunk);
+ break;
+ case SCTP_CMD_CLEAR_INIT_TAG:
+ asoc->peer.i.init_tag = 0;
+ break;
+ case SCTP_CMD_DEL_NON_PRIMARY:
+ sctp_cmd_del_non_primary(asoc);
+ break;
+ case SCTP_CMD_T3_RTX_TIMERS_STOP:
+ sctp_cmd_t3_rtx_timers_stop(commands, asoc);
+ break;
+ case SCTP_CMD_FORCE_PRIM_RETRAN:
+ t = asoc->peer.retran_path;
+ asoc->peer.retran_path = asoc->peer.primary_path;
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+ local_cork = 0;
+ asoc->peer.retran_path = t;
+ break;
+ case SCTP_CMD_SET_SK_ERR:
+ sctp_cmd_set_sk_err(asoc, cmd->obj.error);
+ break;
+ case SCTP_CMD_ASSOC_CHANGE:
+ sctp_cmd_assoc_change(commands, asoc,
+ cmd->obj.u8);
+ break;
+ case SCTP_CMD_ADAPTATION_IND:
+ sctp_cmd_adaptation_ind(commands, asoc);
+ break;
+ case SCTP_CMD_PEER_NO_AUTH:
+ sctp_cmd_peer_no_auth(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;
+ }
+ sctp_cmd_send_msg(asoc, cmd->obj.msg, gfp);
+ break;
+ case SCTP_CMD_SEND_NEXT_ASCONF:
+ sctp_cmd_send_asconf(asoc);
+ break;
+ case SCTP_CMD_PURGE_ASCONF_QUEUE:
+ sctp_asconf_queue_teardown(asoc);
+ break;
+
+ case SCTP_CMD_SET_ASOC:
+ if (asoc && local_cork) {
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+ local_cork = 0;
+ }
+ asoc = cmd->obj.asoc;
+ break;
+
+ default:
+ pr_warn("Impossible command: %u\n",
+ cmd->verb);
+ break;
+ }
+
+ if (error)
+ break;
+ }
+
+out:
+ /* If this is in response to a received chunk, wait until
+ * we are done with the packet to open the queue so that we don't
+ * send multiple packets in response to a single request.
+ */
+ if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) {
+ if (chunk->end_of_packet || chunk->singleton)
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+ } else if (local_cork)
+ sctp_outq_uncork(&asoc->outqueue, gfp);
+
+ if (sp->data_ready_signalled)
+ sp->data_ready_signalled = 0;
+
+ return error;
+nomem:
+ error = -ENOMEM;
+ goto out;
+}