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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
42static 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 checking for match
70 *
71 * Returns true if there is overlap, otherwise false.
72 */
73static 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
86void 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
106static 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
116static void tipc_sub_kref_release(struct kref *kref)
117{
118 kfree(container_of(kref, struct tipc_subscription, kref));
119}
120
121void tipc_sub_put(struct tipc_subscription *subscription)
122{
123 kref_put(&subscription->kref, tipc_sub_kref_release);
124}
125
126void tipc_sub_get(struct tipc_subscription *subscription)
127{
128 kref_get(&subscription->kref);
129}
130
131struct 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
176void 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}
1/*
2 * net/tipc/subscr.c: TIPC network topology service
3 *
4 * Copyright (c) 2000-2006, Ericsson AB
5 * Copyright (c) 2005-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "name_table.h"
39#include "subscr.h"
40
41/**
42 * struct tipc_subscriber - TIPC network topology subscriber
43 * @kref: reference counter to tipc_subscription object
44 * @conid: connection identifier to server connecting to subscriber
45 * @lock: control access to subscriber
46 * @subscrp_list: list of subscription objects for this subscriber
47 */
48struct tipc_subscriber {
49 struct kref kref;
50 int conid;
51 spinlock_t lock;
52 struct list_head subscrp_list;
53};
54
55static void tipc_subscrp_delete(struct tipc_subscription *sub);
56static void tipc_subscrb_put(struct tipc_subscriber *subscriber);
57
58/**
59 * htohl - convert value to endianness used by destination
60 * @in: value to convert
61 * @swap: non-zero if endianness must be reversed
62 *
63 * Returns converted value
64 */
65static u32 htohl(u32 in, int swap)
66{
67 return swap ? swab32(in) : in;
68}
69
70static void tipc_subscrp_send_event(struct tipc_subscription *sub,
71 u32 found_lower, u32 found_upper,
72 u32 event, u32 port_ref, u32 node)
73{
74 struct tipc_net *tn = net_generic(sub->net, tipc_net_id);
75 struct tipc_subscriber *subscriber = sub->subscriber;
76 struct kvec msg_sect;
77
78 msg_sect.iov_base = (void *)&sub->evt;
79 msg_sect.iov_len = sizeof(struct tipc_event);
80 sub->evt.event = htohl(event, sub->swap);
81 sub->evt.found_lower = htohl(found_lower, sub->swap);
82 sub->evt.found_upper = htohl(found_upper, sub->swap);
83 sub->evt.port.ref = htohl(port_ref, sub->swap);
84 sub->evt.port.node = htohl(node, sub->swap);
85 tipc_conn_sendmsg(tn->topsrv, subscriber->conid, NULL,
86 msg_sect.iov_base, msg_sect.iov_len);
87}
88
89/**
90 * tipc_subscrp_check_overlap - test for subscription overlap with the
91 * given values
92 *
93 * Returns 1 if there is overlap, otherwise 0.
94 */
95int tipc_subscrp_check_overlap(struct tipc_name_seq *seq, u32 found_lower,
96 u32 found_upper)
97{
98 if (found_lower < seq->lower)
99 found_lower = seq->lower;
100 if (found_upper > seq->upper)
101 found_upper = seq->upper;
102 if (found_lower > found_upper)
103 return 0;
104 return 1;
105}
106
107u32 tipc_subscrp_convert_seq_type(u32 type, int swap)
108{
109 return htohl(type, swap);
110}
111
112void tipc_subscrp_convert_seq(struct tipc_name_seq *in, int swap,
113 struct tipc_name_seq *out)
114{
115 out->type = htohl(in->type, swap);
116 out->lower = htohl(in->lower, swap);
117 out->upper = htohl(in->upper, swap);
118}
119
120void tipc_subscrp_report_overlap(struct tipc_subscription *sub, u32 found_lower,
121 u32 found_upper, u32 event, u32 port_ref,
122 u32 node, int must)
123{
124 struct tipc_name_seq seq;
125
126 tipc_subscrp_convert_seq(&sub->evt.s.seq, sub->swap, &seq);
127 if (!tipc_subscrp_check_overlap(&seq, found_lower, found_upper))
128 return;
129 if (!must &&
130 !(htohl(sub->evt.s.filter, sub->swap) & TIPC_SUB_PORTS))
131 return;
132
133 tipc_subscrp_send_event(sub, found_lower, found_upper, event, port_ref,
134 node);
135}
136
137static void tipc_subscrp_timeout(unsigned long data)
138{
139 struct tipc_subscription *sub = (struct tipc_subscription *)data;
140 struct tipc_subscriber *subscriber = sub->subscriber;
141
142 /* Notify subscriber of timeout */
143 tipc_subscrp_send_event(sub, sub->evt.s.seq.lower, sub->evt.s.seq.upper,
144 TIPC_SUBSCR_TIMEOUT, 0, 0);
145
146 spin_lock_bh(&subscriber->lock);
147 tipc_subscrp_delete(sub);
148 spin_unlock_bh(&subscriber->lock);
149
150 tipc_subscrb_put(subscriber);
151}
152
153static void tipc_subscrb_kref_release(struct kref *kref)
154{
155 struct tipc_subscriber *subcriber = container_of(kref,
156 struct tipc_subscriber, kref);
157
158 kfree(subcriber);
159}
160
161static void tipc_subscrb_put(struct tipc_subscriber *subscriber)
162{
163 kref_put(&subscriber->kref, tipc_subscrb_kref_release);
164}
165
166static void tipc_subscrb_get(struct tipc_subscriber *subscriber)
167{
168 kref_get(&subscriber->kref);
169}
170
171static struct tipc_subscriber *tipc_subscrb_create(int conid)
172{
173 struct tipc_subscriber *subscriber;
174
175 subscriber = kzalloc(sizeof(*subscriber), GFP_ATOMIC);
176 if (!subscriber) {
177 pr_warn("Subscriber rejected, no memory\n");
178 return NULL;
179 }
180 kref_init(&subscriber->kref);
181 INIT_LIST_HEAD(&subscriber->subscrp_list);
182 subscriber->conid = conid;
183 spin_lock_init(&subscriber->lock);
184
185 return subscriber;
186}
187
188static void tipc_subscrb_delete(struct tipc_subscriber *subscriber)
189{
190 struct tipc_subscription *sub, *temp;
191 u32 timeout;
192
193 spin_lock_bh(&subscriber->lock);
194 /* Destroy any existing subscriptions for subscriber */
195 list_for_each_entry_safe(sub, temp, &subscriber->subscrp_list,
196 subscrp_list) {
197 timeout = htohl(sub->evt.s.timeout, sub->swap);
198 if ((timeout == TIPC_WAIT_FOREVER) || del_timer(&sub->timer)) {
199 tipc_subscrp_delete(sub);
200 tipc_subscrb_put(subscriber);
201 }
202 }
203 spin_unlock_bh(&subscriber->lock);
204
205 tipc_subscrb_put(subscriber);
206}
207
208static void tipc_subscrp_delete(struct tipc_subscription *sub)
209{
210 struct tipc_net *tn = net_generic(sub->net, tipc_net_id);
211
212 tipc_nametbl_unsubscribe(sub);
213 list_del(&sub->subscrp_list);
214 kfree(sub);
215 atomic_dec(&tn->subscription_count);
216}
217
218static void tipc_subscrp_cancel(struct tipc_subscr *s,
219 struct tipc_subscriber *subscriber)
220{
221 struct tipc_subscription *sub, *temp;
222 u32 timeout;
223
224 spin_lock_bh(&subscriber->lock);
225 /* Find first matching subscription, exit if not found */
226 list_for_each_entry_safe(sub, temp, &subscriber->subscrp_list,
227 subscrp_list) {
228 if (!memcmp(s, &sub->evt.s, sizeof(struct tipc_subscr))) {
229 timeout = htohl(sub->evt.s.timeout, sub->swap);
230 if ((timeout == TIPC_WAIT_FOREVER) ||
231 del_timer(&sub->timer)) {
232 tipc_subscrp_delete(sub);
233 tipc_subscrb_put(subscriber);
234 }
235 break;
236 }
237 }
238 spin_unlock_bh(&subscriber->lock);
239}
240
241static struct tipc_subscription *tipc_subscrp_create(struct net *net,
242 struct tipc_subscr *s,
243 int swap)
244{
245 struct tipc_net *tn = net_generic(net, tipc_net_id);
246 struct tipc_subscription *sub;
247 u32 filter = htohl(s->filter, swap);
248
249 /* Refuse subscription if global limit exceeded */
250 if (atomic_read(&tn->subscription_count) >= TIPC_MAX_SUBSCRIPTIONS) {
251 pr_warn("Subscription rejected, limit reached (%u)\n",
252 TIPC_MAX_SUBSCRIPTIONS);
253 return NULL;
254 }
255
256 /* Allocate subscription object */
257 sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
258 if (!sub) {
259 pr_warn("Subscription rejected, no memory\n");
260 return NULL;
261 }
262
263 /* Initialize subscription object */
264 sub->net = net;
265 if (((filter & TIPC_SUB_PORTS) && (filter & TIPC_SUB_SERVICE)) ||
266 (htohl(s->seq.lower, swap) > htohl(s->seq.upper, swap))) {
267 pr_warn("Subscription rejected, illegal request\n");
268 kfree(sub);
269 return NULL;
270 }
271
272 sub->swap = swap;
273 memcpy(&sub->evt.s, s, sizeof(*s));
274 atomic_inc(&tn->subscription_count);
275 return sub;
276}
277
278static void tipc_subscrp_subscribe(struct net *net, struct tipc_subscr *s,
279 struct tipc_subscriber *subscriber, int swap)
280{
281 struct tipc_net *tn = net_generic(net, tipc_net_id);
282 struct tipc_subscription *sub = NULL;
283 u32 timeout;
284
285 sub = tipc_subscrp_create(net, s, swap);
286 if (!sub)
287 return tipc_conn_terminate(tn->topsrv, subscriber->conid);
288
289 spin_lock_bh(&subscriber->lock);
290 list_add(&sub->subscrp_list, &subscriber->subscrp_list);
291 tipc_subscrb_get(subscriber);
292 sub->subscriber = subscriber;
293 tipc_nametbl_subscribe(sub);
294 spin_unlock_bh(&subscriber->lock);
295
296 timeout = htohl(sub->evt.s.timeout, swap);
297 if (timeout == TIPC_WAIT_FOREVER)
298 return;
299
300 setup_timer(&sub->timer, tipc_subscrp_timeout, (unsigned long)sub);
301 mod_timer(&sub->timer, jiffies + msecs_to_jiffies(timeout));
302}
303
304/* Handle one termination request for the subscriber */
305static void tipc_subscrb_shutdown_cb(int conid, void *usr_data)
306{
307 tipc_subscrb_delete((struct tipc_subscriber *)usr_data);
308}
309
310/* Handle one request to create a new subscription for the subscriber */
311static void tipc_subscrb_rcv_cb(struct net *net, int conid,
312 struct sockaddr_tipc *addr, void *usr_data,
313 void *buf, size_t len)
314{
315 struct tipc_subscriber *subscriber = usr_data;
316 struct tipc_subscr *s = (struct tipc_subscr *)buf;
317 int swap;
318
319 /* Determine subscriber's endianness */
320 swap = !(s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE |
321 TIPC_SUB_CANCEL));
322
323 /* Detect & process a subscription cancellation request */
324 if (s->filter & htohl(TIPC_SUB_CANCEL, swap)) {
325 s->filter &= ~htohl(TIPC_SUB_CANCEL, swap);
326 return tipc_subscrp_cancel(s, subscriber);
327 }
328
329 if (s)
330 tipc_subscrp_subscribe(net, s, subscriber, swap);
331}
332
333/* Handle one request to establish a new subscriber */
334static void *tipc_subscrb_connect_cb(int conid)
335{
336 return (void *)tipc_subscrb_create(conid);
337}
338
339int tipc_topsrv_start(struct net *net)
340{
341 struct tipc_net *tn = net_generic(net, tipc_net_id);
342 const char name[] = "topology_server";
343 struct tipc_server *topsrv;
344 struct sockaddr_tipc *saddr;
345
346 saddr = kzalloc(sizeof(*saddr), GFP_ATOMIC);
347 if (!saddr)
348 return -ENOMEM;
349 saddr->family = AF_TIPC;
350 saddr->addrtype = TIPC_ADDR_NAMESEQ;
351 saddr->addr.nameseq.type = TIPC_TOP_SRV;
352 saddr->addr.nameseq.lower = TIPC_TOP_SRV;
353 saddr->addr.nameseq.upper = TIPC_TOP_SRV;
354 saddr->scope = TIPC_NODE_SCOPE;
355
356 topsrv = kzalloc(sizeof(*topsrv), GFP_ATOMIC);
357 if (!topsrv) {
358 kfree(saddr);
359 return -ENOMEM;
360 }
361 topsrv->net = net;
362 topsrv->saddr = saddr;
363 topsrv->imp = TIPC_CRITICAL_IMPORTANCE;
364 topsrv->type = SOCK_SEQPACKET;
365 topsrv->max_rcvbuf_size = sizeof(struct tipc_subscr);
366 topsrv->tipc_conn_recvmsg = tipc_subscrb_rcv_cb;
367 topsrv->tipc_conn_new = tipc_subscrb_connect_cb;
368 topsrv->tipc_conn_shutdown = tipc_subscrb_shutdown_cb;
369
370 strncpy(topsrv->name, name, strlen(name) + 1);
371 tn->topsrv = topsrv;
372 atomic_set(&tn->subscription_count, 0);
373
374 return tipc_server_start(topsrv);
375}
376
377void tipc_topsrv_stop(struct net *net)
378{
379 struct tipc_net *tn = net_generic(net, tipc_net_id);
380 struct tipc_server *topsrv = tn->topsrv;
381
382 tipc_server_stop(topsrv);
383 kfree(topsrv->saddr);
384 kfree(topsrv);
385}