/*
* net/tipc/subscr.c: TIPC network topology service
*
* Copyright (c) 2000-2017, Ericsson AB
* Copyright (c) 2005-2007, 2010-2013, Wind River Systems
* Copyright (c) 2020-2021, Red Hat Inc
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "core.h"
#include "name_table.h"
#include "subscr.h"
static void tipc_sub_send_event(struct tipc_subscription *sub,
struct publication *p,
u32 event)
{
struct tipc_subscr *s = &sub->evt.s;
struct tipc_event *evt = &sub->evt;
if (sub->inactive)
return;
tipc_evt_write(evt, event, event);
if (p) {
tipc_evt_write(evt, found_lower, p->sr.lower);
tipc_evt_write(evt, found_upper, p->sr.upper);
tipc_evt_write(evt, port.ref, p->sk.ref);
tipc_evt_write(evt, port.node, p->sk.node);
} else {
tipc_evt_write(evt, found_lower, s->seq.lower);
tipc_evt_write(evt, found_upper, s->seq.upper);
tipc_evt_write(evt, port.ref, 0);
tipc_evt_write(evt, port.node, 0);
}
tipc_topsrv_queue_evt(sub->net, sub->conid, event, evt);
}
/**
* tipc_sub_check_overlap - test for subscription overlap with the given values
* @subscribed: the service range subscribed for
* @found: the service range we are checking for match
*
* Returns true if there is overlap, otherwise false.
*/
static bool tipc_sub_check_overlap(struct tipc_service_range *subscribed,
struct tipc_service_range *found)
{
u32 found_lower = found->lower;
u32 found_upper = found->upper;
if (found_lower < subscribed->lower)
found_lower = subscribed->lower;
if (found_upper > subscribed->upper)
found_upper = subscribed->upper;
return found_lower <= found_upper;
}
void tipc_sub_report_overlap(struct tipc_subscription *sub,
struct publication *p,
u32 event, bool must)
{
struct tipc_service_range *sr = &sub->s.seq;
u32 filter = sub->s.filter;
if (!tipc_sub_check_overlap(sr, &p->sr))
return;
if (!must && !(filter & TIPC_SUB_PORTS))
return;
if (filter & TIPC_SUB_CLUSTER_SCOPE && p->scope == TIPC_NODE_SCOPE)
return;
if (filter & TIPC_SUB_NODE_SCOPE && p->scope != TIPC_NODE_SCOPE)
return;
spin_lock(&sub->lock);
tipc_sub_send_event(sub, p, event);
spin_unlock(&sub->lock);
}
static void tipc_sub_timeout(struct timer_list *t)
{
struct tipc_subscription *sub = from_timer(sub, t, timer);
spin_lock(&sub->lock);
tipc_sub_send_event(sub, NULL, TIPC_SUBSCR_TIMEOUT);
sub->inactive = true;
spin_unlock(&sub->lock);
}
static void tipc_sub_kref_release(struct kref *kref)
{
kfree(container_of(kref, struct tipc_subscription, kref));
}
void tipc_sub_put(struct tipc_subscription *subscription)
{
kref_put(&subscription->kref, tipc_sub_kref_release);
}
void tipc_sub_get(struct tipc_subscription *subscription)
{
kref_get(&subscription->kref);
}
struct tipc_subscription *tipc_sub_subscribe(struct net *net,
struct tipc_subscr *s,
int conid)
{
u32 lower = tipc_sub_read(s, seq.lower);
u32 upper = tipc_sub_read(s, seq.upper);
u32 filter = tipc_sub_read(s, filter);
struct tipc_subscription *sub;
u32 timeout;
if ((filter & TIPC_SUB_PORTS && filter & TIPC_SUB_SERVICE) ||
lower > upper) {
pr_warn("Subscription rejected, illegal request\n");
return NULL;
}
sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
if (!sub) {
pr_warn("Subscription rejected, no memory\n");
return NULL;
}
INIT_LIST_HEAD(&sub->service_list);
INIT_LIST_HEAD(&sub->sub_list);
sub->net = net;
sub->conid = conid;
sub->inactive = false;
memcpy(&sub->evt.s, s, sizeof(*s));
sub->s.seq.type = tipc_sub_read(s, seq.type);
sub->s.seq.lower = lower;
sub->s.seq.upper = upper;
sub->s.filter = filter;
sub->s.timeout = tipc_sub_read(s, timeout);
memcpy(sub->s.usr_handle, s->usr_handle, 8);
spin_lock_init(&sub->lock);
kref_init(&sub->kref);
if (!tipc_nametbl_subscribe(sub)) {
kfree(sub);
return NULL;
}
timer_setup(&sub->timer, tipc_sub_timeout, 0);
timeout = tipc_sub_read(&sub->evt.s, timeout);
if (timeout != TIPC_WAIT_FOREVER)
mod_timer(&sub->timer, jiffies + msecs_to_jiffies(timeout));
return sub;
}
void tipc_sub_unsubscribe(struct tipc_subscription *sub)
{
tipc_nametbl_unsubscribe(sub);
if (sub->evt.s.timeout != TIPC_WAIT_FOREVER)
del_timer_sync(&sub->timer);
list_del(&sub->sub_list);
tipc_sub_put(sub);
}
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