Commit | Line | Data |
---|---|---|
b97bf3fd | 1 | /* |
5b06c85c | 2 | * net/tipc/subscr.c: TIPC network topology service |
c4307285 | 3 | * |
593a5f22 | 4 | * Copyright (c) 2000-2006, Ericsson AB |
13a2e898 | 5 | * Copyright (c) 2005-2007, 2010-2013, Wind River Systems |
b97bf3fd PL |
6 | * All rights reserved. |
7 | * | |
9ea1fd3c | 8 | * Redistribution and use in source and binary forms, with or without |
b97bf3fd PL |
9 | * modification, are permitted provided that the following conditions are met: |
10 | * | |
9ea1fd3c PL |
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. | |
b97bf3fd | 19 | * |
9ea1fd3c PL |
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 | |
b97bf3fd PL |
34 | * POSSIBILITY OF SUCH DAMAGE. |
35 | */ | |
36 | ||
37 | #include "core.h" | |
b97bf3fd | 38 | #include "name_table.h" |
5b06c85c | 39 | #include "subscr.h" |
b97bf3fd PL |
40 | |
41 | /** | |
11f99906 | 42 | * struct tipc_subscriber - TIPC network topology subscriber |
13a2e898 | 43 | * @conid: connection identifier to server connecting to subscriber |
963a1855 | 44 | * @lock: control access to subscriber |
b97bf3fd | 45 | * @subscription_list: list of subscription objects for this subscriber |
b97bf3fd | 46 | */ |
11f99906 | 47 | struct tipc_subscriber { |
13a2e898 YX |
48 | int conid; |
49 | spinlock_t lock; | |
b97bf3fd | 50 | struct list_head subscription_list; |
b97bf3fd PL |
51 | }; |
52 | ||
4ac1c8d0 YX |
53 | static void subscr_conn_msg_event(struct net *net, int conid, |
54 | struct sockaddr_tipc *addr, void *usr_data, | |
55 | void *buf, size_t len); | |
13a2e898 YX |
56 | static void *subscr_named_msg_event(int conid); |
57 | static void subscr_conn_shutdown_event(int conid, void *usr_data); | |
58 | ||
59 | static atomic_t subscription_count = ATOMIC_INIT(0); | |
60 | ||
61 | static 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 | |
b97bf3fd PL |
68 | }; |
69 | ||
13a2e898 YX |
70 | static 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 | }; | |
b97bf3fd | 80 | |
db5a753b NH |
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 | */ | |
db5a753b NH |
88 | static u32 htohl(u32 in, int swap) |
89 | { | |
90 | return swap ? swab32(in) : in; | |
91 | } | |
92 | ||
13a2e898 YX |
93 | static void subscr_send_event(struct tipc_subscription *sub, u32 found_lower, |
94 | u32 found_upper, u32 event, u32 port_ref, | |
b97bf3fd PL |
95 | u32 node) |
96 | { | |
13a2e898 YX |
97 | struct tipc_subscriber *subscriber = sub->subscriber; |
98 | struct kvec msg_sect; | |
b97bf3fd PL |
99 | |
100 | msg_sect.iov_base = (void *)&sub->evt; | |
101 | msg_sect.iov_len = sizeof(struct tipc_event); | |
db5a753b NH |
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); | |
6d4ebeb4 YX |
107 | tipc_conn_sendmsg(&topsrv, subscriber->conid, NULL, msg_sect.iov_base, |
108 | msg_sect.iov_len); | |
b97bf3fd PL |
109 | } |
110 | ||
111 | /** | |
4323add6 | 112 | * tipc_subscr_overlap - test for subscription overlap with the given values |
b97bf3fd PL |
113 | * |
114 | * Returns 1 if there is overlap, otherwise 0. | |
115 | */ | |
ae8509c4 | 116 | int tipc_subscr_overlap(struct tipc_subscription *sub, u32 found_lower, |
4323add6 | 117 | u32 found_upper) |
b97bf3fd PL |
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 | /** | |
4323add6 | 129 | * tipc_subscr_report_overlap - issue event if there is subscription overlap |
c4307285 | 130 | * |
b97bf3fd PL |
131 | * Protected by nameseq.lock in name_table.c |
132 | */ | |
ae8509c4 PG |
133 | void 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) | |
b97bf3fd | 136 | { |
4323add6 | 137 | if (!tipc_subscr_overlap(sub, found_lower, found_upper)) |
b97bf3fd | 138 | return; |
eb409460 | 139 | if (!must && !(sub->filter & TIPC_SUB_PORTS)) |
b97bf3fd | 140 | return; |
e15f8804 | 141 | |
7e244776 | 142 | subscr_send_event(sub, found_lower, found_upper, event, port_ref, node); |
b97bf3fd PL |
143 | } |
144 | ||
2f55c437 | 145 | static void subscr_timeout(unsigned long data) |
b97bf3fd | 146 | { |
2f55c437 | 147 | struct tipc_subscription *sub = (struct tipc_subscription *)data; |
13a2e898 | 148 | struct tipc_subscriber *subscriber = sub->subscriber; |
b97bf3fd | 149 | |
13a2e898 YX |
150 | /* The spin lock per subscriber is used to protect its members */ |
151 | spin_lock_bh(&subscriber->lock); | |
152 | ||
eb409460 | 153 | /* Validate timeout (in case subscription is being cancelled) */ |
eb409460 | 154 | if (sub->timeout == TIPC_WAIT_FOREVER) { |
13a2e898 | 155 | spin_unlock_bh(&subscriber->lock); |
eb409460 LC |
156 | return; |
157 | } | |
158 | ||
b97bf3fd | 159 | /* Unlink subscription from name table */ |
4323add6 | 160 | tipc_nametbl_unsubscribe(sub); |
b97bf3fd | 161 | |
28353e7f | 162 | /* Unlink subscription from subscriber */ |
b97bf3fd PL |
163 | list_del(&sub->subscription_list); |
164 | ||
13a2e898 | 165 | spin_unlock_bh(&subscriber->lock); |
28353e7f AS |
166 | |
167 | /* Notify subscriber of timeout */ | |
28353e7f AS |
168 | subscr_send_event(sub, sub->evt.s.seq.lower, sub->evt.s.seq.upper, |
169 | TIPC_SUBSCR_TIMEOUT, 0, 0); | |
170 | ||
b97bf3fd | 171 | /* Now destroy subscription */ |
b97bf3fd | 172 | kfree(sub); |
13a2e898 | 173 | atomic_dec(&subscription_count); |
b97bf3fd PL |
174 | } |
175 | ||
eb409460 LC |
176 | /** |
177 | * subscr_del - delete a subscription within a subscription list | |
178 | * | |
13a2e898 | 179 | * Called with subscriber lock held. |
eb409460 | 180 | */ |
fead3909 | 181 | static void subscr_del(struct tipc_subscription *sub) |
eb409460 LC |
182 | { |
183 | tipc_nametbl_unsubscribe(sub); | |
184 | list_del(&sub->subscription_list); | |
185 | kfree(sub); | |
13a2e898 | 186 | atomic_dec(&subscription_count); |
eb409460 LC |
187 | } |
188 | ||
b97bf3fd PL |
189 | /** |
190 | * subscr_terminate - terminate communication with a subscriber | |
c4307285 | 191 | * |
13a2e898 | 192 | * Note: Must call it in process context since it might sleep. |
b97bf3fd | 193 | */ |
11f99906 | 194 | static void subscr_terminate(struct tipc_subscriber *subscriber) |
b97bf3fd | 195 | { |
13a2e898 YX |
196 | tipc_conn_terminate(&topsrv, subscriber->conid); |
197 | } | |
198 | ||
199 | static void subscr_release(struct tipc_subscriber *subscriber) | |
200 | { | |
fead3909 PG |
201 | struct tipc_subscription *sub; |
202 | struct tipc_subscription *sub_temp; | |
b97bf3fd | 203 | |
13a2e898 | 204 | spin_lock_bh(&subscriber->lock); |
b97bf3fd PL |
205 | |
206 | /* Destroy any existing subscriptions for subscriber */ | |
b97bf3fd PL |
207 | list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list, |
208 | subscription_list) { | |
209 | if (sub->timeout != TIPC_WAIT_FOREVER) { | |
13a2e898 | 210 | spin_unlock_bh(&subscriber->lock); |
2f55c437 | 211 | del_timer_sync(&sub->timer); |
13a2e898 | 212 | spin_lock_bh(&subscriber->lock); |
b97bf3fd | 213 | } |
eb409460 | 214 | subscr_del(sub); |
b97bf3fd | 215 | } |
13a2e898 | 216 | spin_unlock_bh(&subscriber->lock); |
28353e7f AS |
217 | |
218 | /* Now destroy subscriber */ | |
b97bf3fd PL |
219 | kfree(subscriber); |
220 | } | |
221 | ||
eb409460 LC |
222 | /** |
223 | * subscr_cancel - handle subscription cancellation request | |
224 | * | |
13a2e898 | 225 | * Called with subscriber lock held. Routine must temporarily release lock |
eb409460 LC |
226 | * to enable the subscription timeout routine to finish without deadlocking; |
227 | * the lock is then reclaimed to allow caller to release it upon return. | |
228 | * | |
229 | * Note that fields of 's' use subscriber's endianness! | |
230 | */ | |
eb409460 | 231 | static void subscr_cancel(struct tipc_subscr *s, |
11f99906 | 232 | struct tipc_subscriber *subscriber) |
eb409460 | 233 | { |
fead3909 PG |
234 | struct tipc_subscription *sub; |
235 | struct tipc_subscription *sub_temp; | |
eb409460 LC |
236 | int found = 0; |
237 | ||
238 | /* Find first matching subscription, exit if not found */ | |
eb409460 LC |
239 | list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list, |
240 | subscription_list) { | |
db5a753b NH |
241 | if (!memcmp(s, &sub->evt.s, sizeof(struct tipc_subscr))) { |
242 | found = 1; | |
243 | break; | |
244 | } | |
eb409460 LC |
245 | } |
246 | if (!found) | |
247 | return; | |
248 | ||
249 | /* Cancel subscription timer (if used), then delete subscription */ | |
eb409460 LC |
250 | if (sub->timeout != TIPC_WAIT_FOREVER) { |
251 | sub->timeout = TIPC_WAIT_FOREVER; | |
13a2e898 | 252 | spin_unlock_bh(&subscriber->lock); |
2f55c437 | 253 | del_timer_sync(&sub->timer); |
13a2e898 | 254 | spin_lock_bh(&subscriber->lock); |
eb409460 | 255 | } |
eb409460 LC |
256 | subscr_del(sub); |
257 | } | |
258 | ||
b97bf3fd PL |
259 | /** |
260 | * subscr_subscribe - create subscription for subscriber | |
c4307285 | 261 | * |
13a2e898 | 262 | * Called with subscriber lock held. |
b97bf3fd | 263 | */ |
4ac1c8d0 | 264 | static int subscr_subscribe(struct net *net, struct tipc_subscr *s, |
a5d0e7c0 EH |
265 | struct tipc_subscriber *subscriber, |
266 | struct tipc_subscription **sub_p) { | |
fead3909 | 267 | struct tipc_subscription *sub; |
db5a753b NH |
268 | int swap; |
269 | ||
270 | /* Determine subscriber's endianness */ | |
db5a753b | 271 | swap = !(s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE)); |
eb409460 LC |
272 | |
273 | /* Detect & process a subscription cancellation request */ | |
db5a753b NH |
274 | if (s->filter & htohl(TIPC_SUB_CANCEL, swap)) { |
275 | s->filter &= ~htohl(TIPC_SUB_CANCEL, swap); | |
eb409460 | 276 | subscr_cancel(s, subscriber); |
a5d0e7c0 | 277 | return 0; |
eb409460 LC |
278 | } |
279 | ||
b97bf3fd | 280 | /* Refuse subscription if global limit exceeded */ |
13a2e898 | 281 | if (atomic_read(&subscription_count) >= TIPC_MAX_SUBSCRIPTIONS) { |
2cf8aa19 | 282 | pr_warn("Subscription rejected, limit reached (%u)\n", |
34f256cc | 283 | TIPC_MAX_SUBSCRIPTIONS); |
a5d0e7c0 | 284 | return -EINVAL; |
b97bf3fd PL |
285 | } |
286 | ||
287 | /* Allocate subscription object */ | |
28353e7f | 288 | sub = kmalloc(sizeof(*sub), GFP_ATOMIC); |
a10bd924 | 289 | if (!sub) { |
2cf8aa19 | 290 | pr_warn("Subscription rejected, no memory\n"); |
a5d0e7c0 | 291 | return -ENOMEM; |
b97bf3fd PL |
292 | } |
293 | ||
b97bf3fd | 294 | /* Initialize subscription object */ |
4ac1c8d0 | 295 | sub->net = net; |
db5a753b NH |
296 | sub->seq.type = htohl(s->seq.type, swap); |
297 | sub->seq.lower = htohl(s->seq.lower, swap); | |
298 | sub->seq.upper = htohl(s->seq.upper, swap); | |
2f55c437 | 299 | sub->timeout = msecs_to_jiffies(htohl(s->timeout, swap)); |
db5a753b | 300 | sub->filter = htohl(s->filter, swap); |
8c974438 NH |
301 | if ((!(sub->filter & TIPC_SUB_PORTS) == |
302 | !(sub->filter & TIPC_SUB_SERVICE)) || | |
f64f9e71 | 303 | (sub->seq.lower > sub->seq.upper)) { |
2cf8aa19 | 304 | pr_warn("Subscription rejected, illegal request\n"); |
b97bf3fd | 305 | kfree(sub); |
a5d0e7c0 | 306 | return -EINVAL; |
b97bf3fd | 307 | } |
b97bf3fd | 308 | list_add(&sub->subscription_list, &subscriber->subscription_list); |
13a2e898 | 309 | sub->subscriber = subscriber; |
db5a753b | 310 | sub->swap = swap; |
28353e7f | 311 | memcpy(&sub->evt.s, s, sizeof(struct tipc_subscr)); |
13a2e898 | 312 | atomic_inc(&subscription_count); |
b97bf3fd | 313 | if (sub->timeout != TIPC_WAIT_FOREVER) { |
2f55c437 YX |
314 | setup_timer(&sub->timer, subscr_timeout, (unsigned long)sub); |
315 | mod_timer(&sub->timer, jiffies + sub->timeout); | |
b97bf3fd | 316 | } |
a5d0e7c0 EH |
317 | *sub_p = sub; |
318 | return 0; | |
b97bf3fd PL |
319 | } |
320 | ||
13a2e898 YX |
321 | /* Handle one termination request for the subscriber */ |
322 | static void subscr_conn_shutdown_event(int conid, void *usr_data) | |
b97bf3fd | 323 | { |
13a2e898 | 324 | subscr_release((struct tipc_subscriber *)usr_data); |
b97bf3fd PL |
325 | } |
326 | ||
13a2e898 | 327 | /* Handle one request to create a new subscription for the subscriber */ |
4ac1c8d0 YX |
328 | static void subscr_conn_msg_event(struct net *net, int conid, |
329 | struct sockaddr_tipc *addr, void *usr_data, | |
330 | void *buf, size_t len) | |
b97bf3fd | 331 | { |
13a2e898 | 332 | struct tipc_subscriber *subscriber = usr_data; |
a5d0e7c0 | 333 | struct tipc_subscription *sub = NULL; |
28353e7f | 334 | |
13a2e898 | 335 | spin_lock_bh(&subscriber->lock); |
4ac1c8d0 YX |
336 | if (subscr_subscribe(net, (struct tipc_subscr *)buf, subscriber, |
337 | &sub) < 0) { | |
a5d0e7c0 EH |
338 | spin_unlock_bh(&subscriber->lock); |
339 | subscr_terminate(subscriber); | |
340 | return; | |
341 | } | |
13a2e898 YX |
342 | if (sub) |
343 | tipc_nametbl_subscribe(sub); | |
344 | spin_unlock_bh(&subscriber->lock); | |
b97bf3fd PL |
345 | } |
346 | ||
13a2e898 YX |
347 | |
348 | /* Handle one request to establish a new subscriber */ | |
349 | static void *subscr_named_msg_event(int conid) | |
b97bf3fd | 350 | { |
11f99906 | 351 | struct tipc_subscriber *subscriber; |
b97bf3fd PL |
352 | |
353 | /* Create subscriber object */ | |
11f99906 | 354 | subscriber = kzalloc(sizeof(struct tipc_subscriber), GFP_ATOMIC); |
b97bf3fd | 355 | if (subscriber == NULL) { |
2cf8aa19 | 356 | pr_warn("Subscriber rejected, no memory\n"); |
13a2e898 | 357 | return NULL; |
b97bf3fd | 358 | } |
b97bf3fd | 359 | INIT_LIST_HEAD(&subscriber->subscription_list); |
13a2e898 YX |
360 | subscriber->conid = conid; |
361 | spin_lock_init(&subscriber->lock); | |
28353e7f | 362 | |
13a2e898 | 363 | return (void *)subscriber; |
b97bf3fd PL |
364 | } |
365 | ||
4323add6 | 366 | int tipc_subscr_start(void) |
b97bf3fd | 367 | { |
13a2e898 | 368 | return tipc_server_start(&topsrv); |
b97bf3fd PL |
369 | } |
370 | ||
4323add6 | 371 | void tipc_subscr_stop(void) |
b97bf3fd | 372 | { |
13a2e898 | 373 | tipc_server_stop(&topsrv); |
b97bf3fd | 374 | } |