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, 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 u32 found_lower, u32 found_upper, 44 u32 event, u32 port, u32 node) 45 { 46 struct tipc_event *evt = &sub->evt; 47 48 if (sub->inactive) 49 return; 50 tipc_evt_write(evt, event, event); 51 tipc_evt_write(evt, found_lower, found_lower); 52 tipc_evt_write(evt, found_upper, found_upper); 53 tipc_evt_write(evt, port.ref, port); 54 tipc_evt_write(evt, port.node, node); 55 tipc_topsrv_queue_evt(sub->net, sub->conid, event, evt); 56 } 57 58 /** 59 * tipc_sub_check_overlap - test for subscription overlap with the given values 60 * @seq: tipc_name_seq to check 61 * @found_lower: lower value to test 62 * @found_upper: upper value to test 63 * 64 * Return: 1 if there is overlap, otherwise 0. 65 */ 66 int tipc_sub_check_overlap(struct tipc_service_range *seq, u32 found_lower, 67 u32 found_upper) 68 { 69 if (found_lower < seq->lower) 70 found_lower = seq->lower; 71 if (found_upper > seq->upper) 72 found_upper = seq->upper; 73 if (found_lower > found_upper) 74 return 0; 75 return 1; 76 } 77 78 void tipc_sub_report_overlap(struct tipc_subscription *sub, 79 u32 found_lower, u32 found_upper, 80 u32 event, u32 port, u32 node, 81 u32 scope, int must) 82 { 83 struct tipc_subscr *s = &sub->evt.s; 84 u32 filter = tipc_sub_read(s, filter); 85 struct tipc_service_range seq; 86 87 seq.type = tipc_sub_read(s, seq.type); 88 seq.lower = tipc_sub_read(s, seq.lower); 89 seq.upper = tipc_sub_read(s, seq.upper); 90 91 if (!tipc_sub_check_overlap(&seq, found_lower, found_upper)) 92 return; 93 94 if (!must && !(filter & TIPC_SUB_PORTS)) 95 return; 96 if (filter & TIPC_SUB_CLUSTER_SCOPE && scope == TIPC_NODE_SCOPE) 97 return; 98 if (filter & TIPC_SUB_NODE_SCOPE && scope != TIPC_NODE_SCOPE) 99 return; 100 spin_lock(&sub->lock); 101 tipc_sub_send_event(sub, found_lower, found_upper, 102 event, port, node); 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 struct tipc_subscr *s = &sub->evt.s; 110 111 spin_lock(&sub->lock); 112 tipc_sub_send_event(sub, s->seq.lower, s->seq.upper, 113 TIPC_SUBSCR_TIMEOUT, 0, 0); 114 sub->inactive = true; 115 spin_unlock(&sub->lock); 116 } 117 118 static void tipc_sub_kref_release(struct kref *kref) 119 { 120 kfree(container_of(kref, struct tipc_subscription, kref)); 121 } 122 123 void tipc_sub_put(struct tipc_subscription *subscription) 124 { 125 kref_put(&subscription->kref, tipc_sub_kref_release); 126 } 127 128 void tipc_sub_get(struct tipc_subscription *subscription) 129 { 130 kref_get(&subscription->kref); 131 } 132 133 struct tipc_subscription *tipc_sub_subscribe(struct net *net, 134 struct tipc_subscr *s, 135 int conid) 136 { 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 (tipc_sub_read(s, seq.lower) > tipc_sub_read(s, seq.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 spin_lock_init(&sub->lock); 158 kref_init(&sub->kref); 159 if (!tipc_nametbl_subscribe(sub)) { 160 kfree(sub); 161 return NULL; 162 } 163 timer_setup(&sub->timer, tipc_sub_timeout, 0); 164 timeout = tipc_sub_read(&sub->evt.s, timeout); 165 if (timeout != TIPC_WAIT_FOREVER) 166 mod_timer(&sub->timer, jiffies + msecs_to_jiffies(timeout)); 167 return sub; 168 } 169 170 void tipc_sub_unsubscribe(struct tipc_subscription *sub) 171 { 172 tipc_nametbl_unsubscribe(sub); 173 if (sub->evt.s.timeout != TIPC_WAIT_FOREVER) 174 del_timer_sync(&sub->timer); 175 list_del(&sub->sub_list); 176 tipc_sub_put(sub); 177 } 178