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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 "port.h"
40#include "subscr.h"
41
42/**
43 * struct tipc_subscriber - TIPC network topology subscriber
44 * @conid: connection identifier to server connecting to subscriber
45 * @lock: control access to subscriber
46 * @subscription_list: list of subscription objects for this subscriber
47 */
48struct tipc_subscriber {
49 int conid;
50 spinlock_t lock;
51 struct list_head subscription_list;
52};
53
54static void subscr_conn_msg_event(int conid, struct sockaddr_tipc *addr,
55 void *usr_data, void *buf, size_t len);
56static void *subscr_named_msg_event(int conid);
57static void subscr_conn_shutdown_event(int conid, void *usr_data);
58
59static atomic_t subscription_count = ATOMIC_INIT(0);
60
61static struct sockaddr_tipc topsrv_addr __read_mostly = {
62 .family = AF_TIPC,
63 .addrtype = TIPC_ADDR_NAMESEQ,
64 .addr.nameseq.type = TIPC_TOP_SRV,
65 .addr.nameseq.lower = TIPC_TOP_SRV,
66 .addr.nameseq.upper = TIPC_TOP_SRV,
67 .scope = TIPC_NODE_SCOPE
68};
69
70static struct tipc_server topsrv __read_mostly = {
71 .saddr = &topsrv_addr,
72 .imp = TIPC_CRITICAL_IMPORTANCE,
73 .type = SOCK_SEQPACKET,
74 .max_rcvbuf_size = sizeof(struct tipc_subscr),
75 .name = "topology_server",
76 .tipc_conn_recvmsg = subscr_conn_msg_event,
77 .tipc_conn_new = subscr_named_msg_event,
78 .tipc_conn_shutdown = subscr_conn_shutdown_event,
79};
80
81/**
82 * htohl - convert value to endianness used by destination
83 * @in: value to convert
84 * @swap: non-zero if endianness must be reversed
85 *
86 * Returns converted value
87 */
88static u32 htohl(u32 in, int swap)
89{
90 return swap ? swab32(in) : in;
91}
92
93static void subscr_send_event(struct tipc_subscription *sub, u32 found_lower,
94 u32 found_upper, u32 event, u32 port_ref,
95 u32 node)
96{
97 struct tipc_subscriber *subscriber = sub->subscriber;
98 struct kvec msg_sect;
99
100 msg_sect.iov_base = (void *)&sub->evt;
101 msg_sect.iov_len = sizeof(struct tipc_event);
102 sub->evt.event = htohl(event, sub->swap);
103 sub->evt.found_lower = htohl(found_lower, sub->swap);
104 sub->evt.found_upper = htohl(found_upper, sub->swap);
105 sub->evt.port.ref = htohl(port_ref, sub->swap);
106 sub->evt.port.node = htohl(node, sub->swap);
107 tipc_conn_sendmsg(&topsrv, subscriber->conid, NULL, msg_sect.iov_base,
108 msg_sect.iov_len);
109}
110
111/**
112 * tipc_subscr_overlap - test for subscription overlap with the given values
113 *
114 * Returns 1 if there is overlap, otherwise 0.
115 */
116int tipc_subscr_overlap(struct tipc_subscription *sub, u32 found_lower,
117 u32 found_upper)
118{
119 if (found_lower < sub->seq.lower)
120 found_lower = sub->seq.lower;
121 if (found_upper > sub->seq.upper)
122 found_upper = sub->seq.upper;
123 if (found_lower > found_upper)
124 return 0;
125 return 1;
126}
127
128/**
129 * tipc_subscr_report_overlap - issue event if there is subscription overlap
130 *
131 * Protected by nameseq.lock in name_table.c
132 */
133void tipc_subscr_report_overlap(struct tipc_subscription *sub, u32 found_lower,
134 u32 found_upper, u32 event, u32 port_ref,
135 u32 node, int must)
136{
137 if (!tipc_subscr_overlap(sub, found_lower, found_upper))
138 return;
139 if (!must && !(sub->filter & TIPC_SUB_PORTS))
140 return;
141
142 subscr_send_event(sub, found_lower, found_upper, event, port_ref, node);
143}
144
145static void subscr_timeout(struct tipc_subscription *sub)
146{
147 struct tipc_subscriber *subscriber = sub->subscriber;
148
149 /* The spin lock per subscriber is used to protect its members */
150 spin_lock_bh(&subscriber->lock);
151
152 /* Validate timeout (in case subscription is being cancelled) */
153 if (sub->timeout == TIPC_WAIT_FOREVER) {
154 spin_unlock_bh(&subscriber->lock);
155 return;
156 }
157
158 /* Unlink subscription from name table */
159 tipc_nametbl_unsubscribe(sub);
160
161 /* Unlink subscription from subscriber */
162 list_del(&sub->subscription_list);
163
164 spin_unlock_bh(&subscriber->lock);
165
166 /* Notify subscriber of timeout */
167 subscr_send_event(sub, sub->evt.s.seq.lower, sub->evt.s.seq.upper,
168 TIPC_SUBSCR_TIMEOUT, 0, 0);
169
170 /* Now destroy subscription */
171 k_term_timer(&sub->timer);
172 kfree(sub);
173 atomic_dec(&subscription_count);
174}
175
176/**
177 * subscr_del - delete a subscription within a subscription list
178 *
179 * Called with subscriber lock held.
180 */
181static void subscr_del(struct tipc_subscription *sub)
182{
183 tipc_nametbl_unsubscribe(sub);
184 list_del(&sub->subscription_list);
185 kfree(sub);
186 atomic_dec(&subscription_count);
187}
188
189/**
190 * subscr_terminate - terminate communication with a subscriber
191 *
192 * Note: Must call it in process context since it might sleep.
193 */
194static void subscr_terminate(struct tipc_subscriber *subscriber)
195{
196 tipc_conn_terminate(&topsrv, subscriber->conid);
197}
198
199static void subscr_release(struct tipc_subscriber *subscriber)
200{
201 struct tipc_subscription *sub;
202 struct tipc_subscription *sub_temp;
203
204 spin_lock_bh(&subscriber->lock);
205
206 /* Destroy any existing subscriptions for subscriber */
207 list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list,
208 subscription_list) {
209 if (sub->timeout != TIPC_WAIT_FOREVER) {
210 spin_unlock_bh(&subscriber->lock);
211 k_cancel_timer(&sub->timer);
212 k_term_timer(&sub->timer);
213 spin_lock_bh(&subscriber->lock);
214 }
215 subscr_del(sub);
216 }
217 spin_unlock_bh(&subscriber->lock);
218
219 /* Now destroy subscriber */
220 kfree(subscriber);
221}
222
223/**
224 * subscr_cancel - handle subscription cancellation request
225 *
226 * Called with subscriber lock held. Routine must temporarily release lock
227 * to enable the subscription timeout routine to finish without deadlocking;
228 * the lock is then reclaimed to allow caller to release it upon return.
229 *
230 * Note that fields of 's' use subscriber's endianness!
231 */
232static void subscr_cancel(struct tipc_subscr *s,
233 struct tipc_subscriber *subscriber)
234{
235 struct tipc_subscription *sub;
236 struct tipc_subscription *sub_temp;
237 int found = 0;
238
239 /* Find first matching subscription, exit if not found */
240 list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list,
241 subscription_list) {
242 if (!memcmp(s, &sub->evt.s, sizeof(struct tipc_subscr))) {
243 found = 1;
244 break;
245 }
246 }
247 if (!found)
248 return;
249
250 /* Cancel subscription timer (if used), then delete subscription */
251 if (sub->timeout != TIPC_WAIT_FOREVER) {
252 sub->timeout = TIPC_WAIT_FOREVER;
253 spin_unlock_bh(&subscriber->lock);
254 k_cancel_timer(&sub->timer);
255 k_term_timer(&sub->timer);
256 spin_lock_bh(&subscriber->lock);
257 }
258 subscr_del(sub);
259}
260
261/**
262 * subscr_subscribe - create subscription for subscriber
263 *
264 * Called with subscriber lock held.
265 */
266static int subscr_subscribe(struct tipc_subscr *s,
267 struct tipc_subscriber *subscriber,
268 struct tipc_subscription **sub_p) {
269 struct tipc_subscription *sub;
270 int swap;
271
272 /* Determine subscriber's endianness */
273 swap = !(s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE));
274
275 /* Detect & process a subscription cancellation request */
276 if (s->filter & htohl(TIPC_SUB_CANCEL, swap)) {
277 s->filter &= ~htohl(TIPC_SUB_CANCEL, swap);
278 subscr_cancel(s, subscriber);
279 return 0;
280 }
281
282 /* Refuse subscription if global limit exceeded */
283 if (atomic_read(&subscription_count) >= TIPC_MAX_SUBSCRIPTIONS) {
284 pr_warn("Subscription rejected, limit reached (%u)\n",
285 TIPC_MAX_SUBSCRIPTIONS);
286 return -EINVAL;
287 }
288
289 /* Allocate subscription object */
290 sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
291 if (!sub) {
292 pr_warn("Subscription rejected, no memory\n");
293 return -ENOMEM;
294 }
295
296 /* Initialize subscription object */
297 sub->seq.type = htohl(s->seq.type, swap);
298 sub->seq.lower = htohl(s->seq.lower, swap);
299 sub->seq.upper = htohl(s->seq.upper, swap);
300 sub->timeout = htohl(s->timeout, swap);
301 sub->filter = htohl(s->filter, swap);
302 if ((!(sub->filter & TIPC_SUB_PORTS) ==
303 !(sub->filter & TIPC_SUB_SERVICE)) ||
304 (sub->seq.lower > sub->seq.upper)) {
305 pr_warn("Subscription rejected, illegal request\n");
306 kfree(sub);
307 return -EINVAL;
308 }
309 INIT_LIST_HEAD(&sub->nameseq_list);
310 list_add(&sub->subscription_list, &subscriber->subscription_list);
311 sub->subscriber = subscriber;
312 sub->swap = swap;
313 memcpy(&sub->evt.s, s, sizeof(struct tipc_subscr));
314 atomic_inc(&subscription_count);
315 if (sub->timeout != TIPC_WAIT_FOREVER) {
316 k_init_timer(&sub->timer,
317 (Handler)subscr_timeout, (unsigned long)sub);
318 k_start_timer(&sub->timer, sub->timeout);
319 }
320 *sub_p = sub;
321 return 0;
322}
323
324/* Handle one termination request for the subscriber */
325static void subscr_conn_shutdown_event(int conid, void *usr_data)
326{
327 subscr_release((struct tipc_subscriber *)usr_data);
328}
329
330/* Handle one request to create a new subscription for the subscriber */
331static void subscr_conn_msg_event(int conid, struct sockaddr_tipc *addr,
332 void *usr_data, void *buf, size_t len)
333{
334 struct tipc_subscriber *subscriber = usr_data;
335 struct tipc_subscription *sub = NULL;
336
337 spin_lock_bh(&subscriber->lock);
338 if (subscr_subscribe((struct tipc_subscr *)buf, subscriber, &sub) < 0) {
339 spin_unlock_bh(&subscriber->lock);
340 subscr_terminate(subscriber);
341 return;
342 }
343 if (sub)
344 tipc_nametbl_subscribe(sub);
345 spin_unlock_bh(&subscriber->lock);
346}
347
348
349/* Handle one request to establish a new subscriber */
350static void *subscr_named_msg_event(int conid)
351{
352 struct tipc_subscriber *subscriber;
353
354 /* Create subscriber object */
355 subscriber = kzalloc(sizeof(struct tipc_subscriber), GFP_ATOMIC);
356 if (subscriber == NULL) {
357 pr_warn("Subscriber rejected, no memory\n");
358 return NULL;
359 }
360 INIT_LIST_HEAD(&subscriber->subscription_list);
361 subscriber->conid = conid;
362 spin_lock_init(&subscriber->lock);
363
364 return (void *)subscriber;
365}
366
367int tipc_subscr_start(void)
368{
369 return tipc_server_start(&topsrv);
370}
371
372void tipc_subscr_stop(void)
373{
374 tipc_server_stop(&topsrv);
375}
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}