1 /* 2 * net/tipc/subscr.c: TIPC network topology service 3 * 4 * Copyright (c) 2000-2017, Ericsson AB 5 * Copyright (c) 2005-2007, 2010-2013, Wind River Systems 6 * Copyright (c) 2020-2021, Red Hat Inc 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the names of the copyright holders nor the names of its 18 * contributors may be used to endorse or promote products derived from 19 * this software without specific prior written permission. 20 * 21 * Alternatively, this software may be distributed under the terms of the 22 * GNU General Public License ("GPL") version 2 as published by the Free 23 * Software Foundation. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include "core.h" 39 #include "name_table.h" 40 #include "subscr.h" 41 42 static void tipc_sub_send_event(struct tipc_subscription *sub, 43 struct publication *p, 44 u32 event) 45 { 46 struct tipc_subscr *s = &sub->evt.s; 47 struct tipc_event *evt = &sub->evt; 48 49 if (sub->inactive) 50 return; 51 tipc_evt_write(evt, event, event); 52 if (p) { 53 tipc_evt_write(evt, found_lower, p->sr.lower); 54 tipc_evt_write(evt, found_upper, p->sr.upper); 55 tipc_evt_write(evt, port.ref, p->sk.ref); 56 tipc_evt_write(evt, port.node, p->sk.node); 57 } else { 58 tipc_evt_write(evt, found_lower, s->seq.lower); 59 tipc_evt_write(evt, found_upper, s->seq.upper); 60 tipc_evt_write(evt, port.ref, 0); 61 tipc_evt_write(evt, port.node, 0); 62 } 63 tipc_topsrv_queue_evt(sub->net, sub->conid, event, evt); 64 } 65 66 /** 67 * tipc_sub_check_overlap - test for subscription overlap with the given values 68 * @subscribed: the service range subscribed for 69 * @found: the service range we are checning for match 70 * 71 * Returns true if there is overlap, otherwise false. 72 */ 73 static bool tipc_sub_check_overlap(struct tipc_service_range *subscribed, 74 struct tipc_service_range *found) 75 { 76 u32 found_lower = found->lower; 77 u32 found_upper = found->upper; 78 79 if (found_lower < subscribed->lower) 80 found_lower = subscribed->lower; 81 if (found_upper > subscribed->upper) 82 found_upper = subscribed->upper; 83 return found_lower <= found_upper; 84 } 85 86 void tipc_sub_report_overlap(struct tipc_subscription *sub, 87 struct publication *p, 88 u32 event, bool must) 89 { 90 struct tipc_service_range *sr = &sub->s.seq; 91 u32 filter = sub->s.filter; 92 93 if (!tipc_sub_check_overlap(sr, &p->sr)) 94 return; 95 if (!must && !(filter & TIPC_SUB_PORTS)) 96 return; 97 if (filter & TIPC_SUB_CLUSTER_SCOPE && p->scope == TIPC_NODE_SCOPE) 98 return; 99 if (filter & TIPC_SUB_NODE_SCOPE && p->scope != TIPC_NODE_SCOPE) 100 return; 101 spin_lock(&sub->lock); 102 tipc_sub_send_event(sub, p, event); 103 spin_unlock(&sub->lock); 104 } 105 106 static void tipc_sub_timeout(struct timer_list *t) 107 { 108 struct tipc_subscription *sub = from_timer(sub, t, timer); 109 110 spin_lock(&sub->lock); 111 tipc_sub_send_event(sub, NULL, TIPC_SUBSCR_TIMEOUT); 112 sub->inactive = true; 113 spin_unlock(&sub->lock); 114 } 115 116 static void tipc_sub_kref_release(struct kref *kref) 117 { 118 kfree(container_of(kref, struct tipc_subscription, kref)); 119 } 120 121 void tipc_sub_put(struct tipc_subscription *subscription) 122 { 123 kref_put(&subscription->kref, tipc_sub_kref_release); 124 } 125 126 void tipc_sub_get(struct tipc_subscription *subscription) 127 { 128 kref_get(&subscription->kref); 129 } 130 131 struct tipc_subscription *tipc_sub_subscribe(struct net *net, 132 struct tipc_subscr *s, 133 int conid) 134 { 135 u32 lower = tipc_sub_read(s, seq.lower); 136 u32 upper = tipc_sub_read(s, seq.upper); 137 u32 filter = tipc_sub_read(s, filter); 138 struct tipc_subscription *sub; 139 u32 timeout; 140 141 if ((filter & TIPC_SUB_PORTS && filter & TIPC_SUB_SERVICE) || 142 lower > upper) { 143 pr_warn("Subscription rejected, illegal request\n"); 144 return NULL; 145 } 146 sub = kmalloc(sizeof(*sub), GFP_ATOMIC); 147 if (!sub) { 148 pr_warn("Subscription rejected, no memory\n"); 149 return NULL; 150 } 151 INIT_LIST_HEAD(&sub->service_list); 152 INIT_LIST_HEAD(&sub->sub_list); 153 sub->net = net; 154 sub->conid = conid; 155 sub->inactive = false; 156 memcpy(&sub->evt.s, s, sizeof(*s)); 157 sub->s.seq.type = tipc_sub_read(s, seq.type); 158 sub->s.seq.lower = lower; 159 sub->s.seq.upper = upper; 160 sub->s.filter = filter; 161 sub->s.timeout = tipc_sub_read(s, timeout); 162 memcpy(sub->s.usr_handle, s->usr_handle, 8); 163 spin_lock_init(&sub->lock); 164 kref_init(&sub->kref); 165 if (!tipc_nametbl_subscribe(sub)) { 166 kfree(sub); 167 return NULL; 168 } 169 timer_setup(&sub->timer, tipc_sub_timeout, 0); 170 timeout = tipc_sub_read(&sub->evt.s, timeout); 171 if (timeout != TIPC_WAIT_FOREVER) 172 mod_timer(&sub->timer, jiffies + msecs_to_jiffies(timeout)); 173 return sub; 174 } 175 176 void tipc_sub_unsubscribe(struct tipc_subscription *sub) 177 { 178 tipc_nametbl_unsubscribe(sub); 179 if (sub->evt.s.timeout != TIPC_WAIT_FOREVER) 180 del_timer_sync(&sub->timer); 181 list_del(&sub->sub_list); 182 tipc_sub_put(sub); 183 } 184