1 /*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 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 "subscr.h"
39 #include "link.h"
40 #include "bcast.h"
41 #include "socket.h"
42 #include "name_distr.h"
43 #include "discover.h"
44 #include "netlink.h"
45 #include "monitor.h"
46 #include "trace.h"
47 #include "crypto.h"
48
49 #include <linux/pkt_sched.h>
50
51 struct tipc_stats {
52 u32 sent_pkts;
53 u32 recv_pkts;
54 u32 sent_states;
55 u32 recv_states;
56 u32 sent_probes;
57 u32 recv_probes;
58 u32 sent_nacks;
59 u32 recv_nacks;
60 u32 sent_acks;
61 u32 sent_bundled;
62 u32 sent_bundles;
63 u32 recv_bundled;
64 u32 recv_bundles;
65 u32 retransmitted;
66 u32 sent_fragmented;
67 u32 sent_fragments;
68 u32 recv_fragmented;
69 u32 recv_fragments;
70 u32 link_congs; /* # port sends blocked by congestion */
71 u32 deferred_recv;
72 u32 duplicates;
73 u32 max_queue_sz; /* send queue size high water mark */
74 u32 accu_queue_sz; /* used for send queue size profiling */
75 u32 queue_sz_counts; /* used for send queue size profiling */
76 u32 msg_length_counts; /* used for message length profiling */
77 u32 msg_lengths_total; /* used for message length profiling */
78 u32 msg_length_profile[7]; /* used for msg. length profiling */
79 };
80
81 /**
82 * struct tipc_link - TIPC link data structure
83 * @addr: network address of link's peer node
84 * @name: link name character string
85 * @media_addr: media address to use when sending messages over link
86 * @timer: link timer
87 * @net: pointer to namespace struct
88 * @refcnt: reference counter for permanent references (owner node & timer)
89 * @peer_session: link session # being used by peer end of link
90 * @peer_bearer_id: bearer id used by link's peer endpoint
91 * @bearer_id: local bearer id used by link
92 * @tolerance: minimum link continuity loss needed to reset link [in ms]
93 * @abort_limit: # of unacknowledged continuity probes needed to reset link
94 * @state: current state of link FSM
95 * @peer_caps: bitmap describing capabilities of peer node
96 * @silent_intv_cnt: # of timer intervals without any reception from peer
97 * @proto_msg: template for control messages generated by link
98 * @pmsg: convenience pointer to "proto_msg" field
99 * @priority: current link priority
100 * @net_plane: current link network plane ('A' through 'H')
101 * @mon_state: cookie with information needed by link monitor
102 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
103 * @exp_msg_count: # of tunnelled messages expected during link changeover
104 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
105 * @mtu: current maximum packet size for this link
106 * @advertised_mtu: advertised own mtu when link is being established
107 * @transmitq: queue for sent, non-acked messages
108 * @backlogq: queue for messages waiting to be sent
109 * @snt_nxt: next sequence number to use for outbound messages
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 */
124 struct tipc_link {
125 u32 addr;
126 char name[TIPC_MAX_LINK_NAME];
127 struct net *net;
128
129 /* Management and link supervision data */
130 u16 peer_session;
131 u16 session;
132 u16 snd_nxt_state;
133 u16 rcv_nxt_state;
134 u32 peer_bearer_id;
135 u32 bearer_id;
136 u32 tolerance;
137 u32 abort_limit;
138 u32 state;
139 u16 peer_caps;
140 bool in_session;
141 bool active;
142 u32 silent_intv_cnt;
143 char if_name[TIPC_MAX_IF_NAME];
144 u32 priority;
145 char net_plane;
146 struct tipc_mon_state mon_state;
147 u16 rst_cnt;
148
149 /* Failover/synch */
150 u16 drop_point;
151 struct sk_buff *failover_reasm_skb;
152 struct sk_buff_head failover_deferdq;
153
154 /* Max packet negotiation */
155 u16 mtu;
156 u16 advertised_mtu;
157
158 /* Sending */
159 struct sk_buff_head transmq;
160 struct sk_buff_head backlogq;
161 struct {
162 u16 len;
163 u16 limit;
164 struct sk_buff *target_bskb;
165 } backlog[5];
166 u16 snd_nxt;
167
168 /* Reception */
169 u16 rcv_nxt;
170 u32 rcv_unacked;
171 struct sk_buff_head deferdq;
172 struct sk_buff_head *inputq;
173 struct sk_buff_head *namedq;
174
175 /* Congestion handling */
176 struct sk_buff_head wakeupq;
177 u16 window;
178 u16 min_win;
179 u16 ssthresh;
180 u16 max_win;
181 u16 cong_acks;
182 u16 checkpoint;
183
184 /* Fragmentation/reassembly */
185 struct sk_buff *reasm_buf;
186 struct sk_buff *reasm_tnlmsg;
187
188 /* Broadcast */
189 u16 ackers;
190 u16 acked;
191 u16 last_gap;
192 struct tipc_gap_ack_blks *last_ga;
193 struct tipc_link *bc_rcvlink;
194 struct tipc_link *bc_sndlink;
195 u8 nack_state;
196 bool bc_peer_is_up;
197
198 /* Statistics */
199 struct tipc_stats stats;
200 };
201
202 /*
203 * Error message prefixes
204 */
205 static const char *link_co_err = "Link tunneling error, ";
206 static const char *link_rst_msg = "Resetting link ";
207
208 /* Send states for broadcast NACKs
209 */
210 enum {
211 BC_NACK_SND_CONDITIONAL,
212 BC_NACK_SND_UNCONDITIONAL,
213 BC_NACK_SND_SUPPRESS,
214 };
215
216 #define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
217 #define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
218
219 /* Link FSM states:
220 */
221 enum {
222 LINK_ESTABLISHED = 0xe,
223 LINK_ESTABLISHING = 0xe << 4,
224 LINK_RESET = 0x1 << 8,
225 LINK_RESETTING = 0x2 << 12,
226 LINK_PEER_RESET = 0xd << 16,
227 LINK_FAILINGOVER = 0xf << 20,
228 LINK_SYNCHING = 0xc << 24
229 };
230
231 /* Link FSM state checking routines
232 */
link_is_up(struct tipc_link * l)233 static int link_is_up(struct tipc_link *l)
234 {
235 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
236 }
237
238 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
239 struct sk_buff_head *xmitq);
240 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
241 bool probe_reply, u16 rcvgap,
242 int tolerance, int priority,
243 struct sk_buff_head *xmitq);
244 static void link_print(struct tipc_link *l, const char *str);
245 static int tipc_link_build_nack_msg(struct tipc_link *l,
246 struct sk_buff_head *xmitq);
247 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
248 struct sk_buff_head *xmitq);
249 static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
250 struct tipc_link *l, u8 start_index);
251 static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
252 static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
253 u16 acked, u16 gap,
254 struct tipc_gap_ack_blks *ga,
255 struct sk_buff_head *xmitq,
256 bool *retransmitted, int *rc);
257 static void tipc_link_update_cwin(struct tipc_link *l, int released,
258 bool retransmitted);
259 /*
260 * Simple non-static link routines (i.e. referenced outside this file)
261 */
tipc_link_is_up(struct tipc_link * l)262 bool tipc_link_is_up(struct tipc_link *l)
263 {
264 return link_is_up(l);
265 }
266
tipc_link_peer_is_down(struct tipc_link * l)267 bool tipc_link_peer_is_down(struct tipc_link *l)
268 {
269 return l->state == LINK_PEER_RESET;
270 }
271
tipc_link_is_reset(struct tipc_link * l)272 bool tipc_link_is_reset(struct tipc_link *l)
273 {
274 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
275 }
276
tipc_link_is_establishing(struct tipc_link * l)277 bool tipc_link_is_establishing(struct tipc_link *l)
278 {
279 return l->state == LINK_ESTABLISHING;
280 }
281
tipc_link_is_synching(struct tipc_link * l)282 bool tipc_link_is_synching(struct tipc_link *l)
283 {
284 return l->state == LINK_SYNCHING;
285 }
286
tipc_link_is_failingover(struct tipc_link * l)287 bool tipc_link_is_failingover(struct tipc_link *l)
288 {
289 return l->state == LINK_FAILINGOVER;
290 }
291
tipc_link_is_blocked(struct tipc_link * l)292 bool tipc_link_is_blocked(struct tipc_link *l)
293 {
294 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
295 }
296
link_is_bc_sndlink(struct tipc_link * l)297 static bool link_is_bc_sndlink(struct tipc_link *l)
298 {
299 return !l->bc_sndlink;
300 }
301
link_is_bc_rcvlink(struct tipc_link * l)302 static bool link_is_bc_rcvlink(struct tipc_link *l)
303 {
304 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
305 }
306
tipc_link_set_active(struct tipc_link * l,bool active)307 void tipc_link_set_active(struct tipc_link *l, bool active)
308 {
309 l->active = active;
310 }
311
tipc_link_id(struct tipc_link * l)312 u32 tipc_link_id(struct tipc_link *l)
313 {
314 return l->peer_bearer_id << 16 | l->bearer_id;
315 }
316
tipc_link_min_win(struct tipc_link * l)317 int tipc_link_min_win(struct tipc_link *l)
318 {
319 return l->min_win;
320 }
321
tipc_link_max_win(struct tipc_link * l)322 int tipc_link_max_win(struct tipc_link *l)
323 {
324 return l->max_win;
325 }
326
tipc_link_prio(struct tipc_link * l)327 int tipc_link_prio(struct tipc_link *l)
328 {
329 return l->priority;
330 }
331
tipc_link_tolerance(struct tipc_link * l)332 unsigned long tipc_link_tolerance(struct tipc_link *l)
333 {
334 return l->tolerance;
335 }
336
tipc_link_inputq(struct tipc_link * l)337 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
338 {
339 return l->inputq;
340 }
341
tipc_link_plane(struct tipc_link * l)342 char tipc_link_plane(struct tipc_link *l)
343 {
344 return l->net_plane;
345 }
346
tipc_link_update_caps(struct tipc_link * l,u16 capabilities)347 void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
348 {
349 l->peer_caps = capabilities;
350 }
351
tipc_link_add_bc_peer(struct tipc_link * snd_l,struct tipc_link * uc_l,struct sk_buff_head * xmitq)352 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
353 struct tipc_link *uc_l,
354 struct sk_buff_head *xmitq)
355 {
356 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
357
358 snd_l->ackers++;
359 rcv_l->acked = snd_l->snd_nxt - 1;
360 snd_l->state = LINK_ESTABLISHED;
361 tipc_link_build_bc_init_msg(uc_l, xmitq);
362 }
363
tipc_link_remove_bc_peer(struct tipc_link * snd_l,struct tipc_link * rcv_l,struct sk_buff_head * xmitq)364 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
365 struct tipc_link *rcv_l,
366 struct sk_buff_head *xmitq)
367 {
368 u16 ack = snd_l->snd_nxt - 1;
369
370 snd_l->ackers--;
371 rcv_l->bc_peer_is_up = true;
372 rcv_l->state = LINK_ESTABLISHED;
373 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
374 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
375 tipc_link_reset(rcv_l);
376 rcv_l->state = LINK_RESET;
377 if (!snd_l->ackers) {
378 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
379 tipc_link_reset(snd_l);
380 snd_l->state = LINK_RESET;
381 __skb_queue_purge(xmitq);
382 }
383 }
384
tipc_link_bc_peers(struct tipc_link * l)385 int tipc_link_bc_peers(struct tipc_link *l)
386 {
387 return l->ackers;
388 }
389
link_bc_rcv_gap(struct tipc_link * l)390 static u16 link_bc_rcv_gap(struct tipc_link *l)
391 {
392 struct sk_buff *skb = skb_peek(&l->deferdq);
393 u16 gap = 0;
394
395 if (more(l->snd_nxt, l->rcv_nxt))
396 gap = l->snd_nxt - l->rcv_nxt;
397 if (skb)
398 gap = buf_seqno(skb) - l->rcv_nxt;
399 return gap;
400 }
401
tipc_link_set_mtu(struct tipc_link * l,int mtu)402 void tipc_link_set_mtu(struct tipc_link *l, int mtu)
403 {
404 l->mtu = mtu;
405 }
406
tipc_link_mtu(struct tipc_link * l)407 int tipc_link_mtu(struct tipc_link *l)
408 {
409 return l->mtu;
410 }
411
tipc_link_mss(struct tipc_link * l)412 int tipc_link_mss(struct tipc_link *l)
413 {
414 #ifdef CONFIG_TIPC_CRYPTO
415 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
416 #else
417 return l->mtu - INT_H_SIZE;
418 #endif
419 }
420
tipc_link_rcv_nxt(struct tipc_link * l)421 u16 tipc_link_rcv_nxt(struct tipc_link *l)
422 {
423 return l->rcv_nxt;
424 }
425
tipc_link_acked(struct tipc_link * l)426 u16 tipc_link_acked(struct tipc_link *l)
427 {
428 return l->acked;
429 }
430
tipc_link_name(struct tipc_link * l)431 char *tipc_link_name(struct tipc_link *l)
432 {
433 return l->name;
434 }
435
tipc_link_state(struct tipc_link * l)436 u32 tipc_link_state(struct tipc_link *l)
437 {
438 return l->state;
439 }
440
441 /**
442 * tipc_link_create - create a new link
443 * @net: pointer to associated network namespace
444 * @if_name: associated interface name
445 * @bearer_id: id (index) of associated bearer
446 * @tolerance: link tolerance to be used by link
447 * @net_plane: network plane (A,B,c..) this link belongs to
448 * @mtu: mtu to be advertised by link
449 * @priority: priority to be used by link
450 * @min_win: minimal send window to be used by link
451 * @max_win: maximal send window to be used by link
452 * @session: session to be used by link
453 * @ownnode: identity of own node
454 * @peer: node id of peer node
455 * @peer_caps: bitmap describing peer node capabilities
456 * @bc_sndlink: the namespace global link used for broadcast sending
457 * @bc_rcvlink: the peer specific link used for broadcast reception
458 * @inputq: queue to put messages ready for delivery
459 * @namedq: queue to put binding table update messages ready for delivery
460 * @link: return value, pointer to put the created link
461 *
462 * Returns true if link was created, otherwise false
463 */
tipc_link_create(struct net * net,char * if_name,int bearer_id,int tolerance,char net_plane,u32 mtu,int priority,u32 min_win,u32 max_win,u32 session,u32 self,u32 peer,u8 * peer_id,u16 peer_caps,struct tipc_link * bc_sndlink,struct tipc_link * bc_rcvlink,struct sk_buff_head * inputq,struct sk_buff_head * namedq,struct tipc_link ** link)464 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
465 int tolerance, char net_plane, u32 mtu, int priority,
466 u32 min_win, u32 max_win, u32 session, u32 self,
467 u32 peer, u8 *peer_id, u16 peer_caps,
468 struct tipc_link *bc_sndlink,
469 struct tipc_link *bc_rcvlink,
470 struct sk_buff_head *inputq,
471 struct sk_buff_head *namedq,
472 struct tipc_link **link)
473 {
474 char peer_str[NODE_ID_STR_LEN] = {0,};
475 char self_str[NODE_ID_STR_LEN] = {0,};
476 struct tipc_link *l;
477
478 l = kzalloc(sizeof(*l), GFP_ATOMIC);
479 if (!l)
480 return false;
481 *link = l;
482 l->session = session;
483
484 /* Set link name for unicast links only */
485 if (peer_id) {
486 tipc_nodeid2string(self_str, tipc_own_id(net));
487 if (strlen(self_str) > 16)
488 sprintf(self_str, "%x", self);
489 tipc_nodeid2string(peer_str, peer_id);
490 if (strlen(peer_str) > 16)
491 sprintf(peer_str, "%x", peer);
492 }
493 /* Peer i/f name will be completed by reset/activate message */
494 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
495 self_str, if_name, peer_str);
496
497 strcpy(l->if_name, if_name);
498 l->addr = peer;
499 l->peer_caps = peer_caps;
500 l->net = net;
501 l->in_session = false;
502 l->bearer_id = bearer_id;
503 l->tolerance = tolerance;
504 if (bc_rcvlink)
505 bc_rcvlink->tolerance = tolerance;
506 l->net_plane = net_plane;
507 l->advertised_mtu = mtu;
508 l->mtu = mtu;
509 l->priority = priority;
510 tipc_link_set_queue_limits(l, min_win, max_win);
511 l->ackers = 1;
512 l->bc_sndlink = bc_sndlink;
513 l->bc_rcvlink = bc_rcvlink;
514 l->inputq = inputq;
515 l->namedq = namedq;
516 l->state = LINK_RESETTING;
517 __skb_queue_head_init(&l->transmq);
518 __skb_queue_head_init(&l->backlogq);
519 __skb_queue_head_init(&l->deferdq);
520 __skb_queue_head_init(&l->failover_deferdq);
521 skb_queue_head_init(&l->wakeupq);
522 skb_queue_head_init(l->inputq);
523 return true;
524 }
525
526 /**
527 * tipc_link_bc_create - create new link to be used for broadcast
528 * @net: pointer to associated network namespace
529 * @mtu: mtu to be used initially if no peers
530 * @min_win: minimal send window to be used by link
531 * @max_win: maximal send window to be used by link
532 * @inputq: queue to put messages ready for delivery
533 * @namedq: queue to put binding table update messages ready for delivery
534 * @link: return value, pointer to put the created link
535 *
536 * Returns true if link was created, otherwise false
537 */
tipc_link_bc_create(struct net * net,u32 ownnode,u32 peer,u8 * peer_id,int mtu,u32 min_win,u32 max_win,u16 peer_caps,struct sk_buff_head * inputq,struct sk_buff_head * namedq,struct tipc_link * bc_sndlink,struct tipc_link ** link)538 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
539 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
540 struct sk_buff_head *inputq,
541 struct sk_buff_head *namedq,
542 struct tipc_link *bc_sndlink,
543 struct tipc_link **link)
544 {
545 struct tipc_link *l;
546
547 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
548 max_win, 0, ownnode, peer, NULL, peer_caps,
549 bc_sndlink, NULL, inputq, namedq, link))
550 return false;
551
552 l = *link;
553 if (peer_id) {
554 char peer_str[NODE_ID_STR_LEN] = {0,};
555
556 tipc_nodeid2string(peer_str, peer_id);
557 if (strlen(peer_str) > 16)
558 sprintf(peer_str, "%x", peer);
559 /* Broadcast receiver link name: "broadcast-link:<peer>" */
560 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
561 peer_str);
562 } else {
563 strcpy(l->name, tipc_bclink_name);
564 }
565 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
566 tipc_link_reset(l);
567 l->state = LINK_RESET;
568 l->ackers = 0;
569 l->bc_rcvlink = l;
570
571 /* Broadcast send link is always up */
572 if (link_is_bc_sndlink(l))
573 l->state = LINK_ESTABLISHED;
574
575 /* Disable replicast if even a single peer doesn't support it */
576 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
577 tipc_bcast_toggle_rcast(net, false);
578
579 return true;
580 }
581
582 /**
583 * tipc_link_fsm_evt - link finite state machine
584 * @l: pointer to link
585 * @evt: state machine event to be processed
586 */
tipc_link_fsm_evt(struct tipc_link * l,int evt)587 int tipc_link_fsm_evt(struct tipc_link *l, int evt)
588 {
589 int rc = 0;
590 int old_state = l->state;
591
592 switch (l->state) {
593 case LINK_RESETTING:
594 switch (evt) {
595 case LINK_PEER_RESET_EVT:
596 l->state = LINK_PEER_RESET;
597 break;
598 case LINK_RESET_EVT:
599 l->state = LINK_RESET;
600 break;
601 case LINK_FAILURE_EVT:
602 case LINK_FAILOVER_BEGIN_EVT:
603 case LINK_ESTABLISH_EVT:
604 case LINK_FAILOVER_END_EVT:
605 case LINK_SYNCH_BEGIN_EVT:
606 case LINK_SYNCH_END_EVT:
607 default:
608 goto illegal_evt;
609 }
610 break;
611 case LINK_RESET:
612 switch (evt) {
613 case LINK_PEER_RESET_EVT:
614 l->state = LINK_ESTABLISHING;
615 break;
616 case LINK_FAILOVER_BEGIN_EVT:
617 l->state = LINK_FAILINGOVER;
618 case LINK_FAILURE_EVT:
619 case LINK_RESET_EVT:
620 case LINK_ESTABLISH_EVT:
621 case LINK_FAILOVER_END_EVT:
622 break;
623 case LINK_SYNCH_BEGIN_EVT:
624 case LINK_SYNCH_END_EVT:
625 default:
626 goto illegal_evt;
627 }
628 break;
629 case LINK_PEER_RESET:
630 switch (evt) {
631 case LINK_RESET_EVT:
632 l->state = LINK_ESTABLISHING;
633 break;
634 case LINK_PEER_RESET_EVT:
635 case LINK_ESTABLISH_EVT:
636 case LINK_FAILURE_EVT:
637 break;
638 case LINK_SYNCH_BEGIN_EVT:
639 case LINK_SYNCH_END_EVT:
640 case LINK_FAILOVER_BEGIN_EVT:
641 case LINK_FAILOVER_END_EVT:
642 default:
643 goto illegal_evt;
644 }
645 break;
646 case LINK_FAILINGOVER:
647 switch (evt) {
648 case LINK_FAILOVER_END_EVT:
649 l->state = LINK_RESET;
650 break;
651 case LINK_PEER_RESET_EVT:
652 case LINK_RESET_EVT:
653 case LINK_ESTABLISH_EVT:
654 case LINK_FAILURE_EVT:
655 break;
656 case LINK_FAILOVER_BEGIN_EVT:
657 case LINK_SYNCH_BEGIN_EVT:
658 case LINK_SYNCH_END_EVT:
659 default:
660 goto illegal_evt;
661 }
662 break;
663 case LINK_ESTABLISHING:
664 switch (evt) {
665 case LINK_ESTABLISH_EVT:
666 l->state = LINK_ESTABLISHED;
667 break;
668 case LINK_FAILOVER_BEGIN_EVT:
669 l->state = LINK_FAILINGOVER;
670 break;
671 case LINK_RESET_EVT:
672 l->state = LINK_RESET;
673 break;
674 case LINK_FAILURE_EVT:
675 case LINK_PEER_RESET_EVT:
676 case LINK_SYNCH_BEGIN_EVT:
677 case LINK_FAILOVER_END_EVT:
678 break;
679 case LINK_SYNCH_END_EVT:
680 default:
681 goto illegal_evt;
682 }
683 break;
684 case LINK_ESTABLISHED:
685 switch (evt) {
686 case LINK_PEER_RESET_EVT:
687 l->state = LINK_PEER_RESET;
688 rc |= TIPC_LINK_DOWN_EVT;
689 break;
690 case LINK_FAILURE_EVT:
691 l->state = LINK_RESETTING;
692 rc |= TIPC_LINK_DOWN_EVT;
693 break;
694 case LINK_RESET_EVT:
695 l->state = LINK_RESET;
696 break;
697 case LINK_ESTABLISH_EVT:
698 case LINK_SYNCH_END_EVT:
699 break;
700 case LINK_SYNCH_BEGIN_EVT:
701 l->state = LINK_SYNCHING;
702 break;
703 case LINK_FAILOVER_BEGIN_EVT:
704 case LINK_FAILOVER_END_EVT:
705 default:
706 goto illegal_evt;
707 }
708 break;
709 case LINK_SYNCHING:
710 switch (evt) {
711 case LINK_PEER_RESET_EVT:
712 l->state = LINK_PEER_RESET;
713 rc |= TIPC_LINK_DOWN_EVT;
714 break;
715 case LINK_FAILURE_EVT:
716 l->state = LINK_RESETTING;
717 rc |= TIPC_LINK_DOWN_EVT;
718 break;
719 case LINK_RESET_EVT:
720 l->state = LINK_RESET;
721 break;
722 case LINK_ESTABLISH_EVT:
723 case LINK_SYNCH_BEGIN_EVT:
724 break;
725 case LINK_SYNCH_END_EVT:
726 l->state = LINK_ESTABLISHED;
727 break;
728 case LINK_FAILOVER_BEGIN_EVT:
729 case LINK_FAILOVER_END_EVT:
730 default:
731 goto illegal_evt;
732 }
733 break;
734 default:
735 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
736 }
737 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
738 return rc;
739 illegal_evt:
740 pr_err("Illegal FSM event %x in state %x on link %s\n",
741 evt, l->state, l->name);
742 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
743 return rc;
744 }
745
746 /* link_profile_stats - update statistical profiling of traffic
747 */
link_profile_stats(struct tipc_link * l)748 static void link_profile_stats(struct tipc_link *l)
749 {
750 struct sk_buff *skb;
751 struct tipc_msg *msg;
752 int length;
753
754 /* Update counters used in statistical profiling of send traffic */
755 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
756 l->stats.queue_sz_counts++;
757
758 skb = skb_peek(&l->transmq);
759 if (!skb)
760 return;
761 msg = buf_msg(skb);
762 length = msg_size(msg);
763
764 if (msg_user(msg) == MSG_FRAGMENTER) {
765 if (msg_type(msg) != FIRST_FRAGMENT)
766 return;
767 length = msg_size(msg_inner_hdr(msg));
768 }
769 l->stats.msg_lengths_total += length;
770 l->stats.msg_length_counts++;
771 if (length <= 64)
772 l->stats.msg_length_profile[0]++;
773 else if (length <= 256)
774 l->stats.msg_length_profile[1]++;
775 else if (length <= 1024)
776 l->stats.msg_length_profile[2]++;
777 else if (length <= 4096)
778 l->stats.msg_length_profile[3]++;
779 else if (length <= 16384)
780 l->stats.msg_length_profile[4]++;
781 else if (length <= 32768)
782 l->stats.msg_length_profile[5]++;
783 else
784 l->stats.msg_length_profile[6]++;
785 }
786
787 /**
788 * tipc_link_too_silent - check if link is "too silent"
789 * @l: tipc link to be checked
790 *
791 * Returns true if the link 'silent_intv_cnt' is about to reach the
792 * 'abort_limit' value, otherwise false
793 */
tipc_link_too_silent(struct tipc_link * l)794 bool tipc_link_too_silent(struct tipc_link *l)
795 {
796 return (l->silent_intv_cnt + 2 > l->abort_limit);
797 }
798
799 /* tipc_link_timeout - perform periodic task as instructed from node timeout
800 */
tipc_link_timeout(struct tipc_link * l,struct sk_buff_head * xmitq)801 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
802 {
803 int mtyp = 0;
804 int rc = 0;
805 bool state = false;
806 bool probe = false;
807 bool setup = false;
808 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
809 u16 bc_acked = l->bc_rcvlink->acked;
810 struct tipc_mon_state *mstate = &l->mon_state;
811
812 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
813 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
814 switch (l->state) {
815 case LINK_ESTABLISHED:
816 case LINK_SYNCHING:
817 mtyp = STATE_MSG;
818 link_profile_stats(l);
819 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
820 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
821 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
822 state = bc_acked != bc_snt;
823 state |= l->bc_rcvlink->rcv_unacked;
824 state |= l->rcv_unacked;
825 state |= !skb_queue_empty(&l->transmq);
826 probe = mstate->probing;
827 probe |= l->silent_intv_cnt;
828 if (probe || mstate->monitoring)
829 l->silent_intv_cnt++;
830 probe |= !skb_queue_empty(&l->deferdq);
831 if (l->snd_nxt == l->checkpoint) {
832 tipc_link_update_cwin(l, 0, 0);
833 probe = true;
834 }
835 l->checkpoint = l->snd_nxt;
836 break;
837 case LINK_RESET:
838 setup = l->rst_cnt++ <= 4;
839 setup |= !(l->rst_cnt % 16);
840 mtyp = RESET_MSG;
841 break;
842 case LINK_ESTABLISHING:
843 setup = true;
844 mtyp = ACTIVATE_MSG;
845 break;
846 case LINK_PEER_RESET:
847 case LINK_RESETTING:
848 case LINK_FAILINGOVER:
849 break;
850 default:
851 break;
852 }
853
854 if (state || probe || setup)
855 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
856
857 return rc;
858 }
859
860 /**
861 * link_schedule_user - schedule a message sender for wakeup after congestion
862 * @l: congested link
863 * @hdr: header of message that is being sent
864 * Create pseudo msg to send back to user when congestion abates
865 */
link_schedule_user(struct tipc_link * l,struct tipc_msg * hdr)866 static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
867 {
868 u32 dnode = tipc_own_addr(l->net);
869 u32 dport = msg_origport(hdr);
870 struct sk_buff *skb;
871
872 /* Create and schedule wakeup pseudo message */
873 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
874 dnode, l->addr, dport, 0, 0);
875 if (!skb)
876 return -ENOBUFS;
877 msg_set_dest_droppable(buf_msg(skb), true);
878 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
879 skb_queue_tail(&l->wakeupq, skb);
880 l->stats.link_congs++;
881 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
882 return -ELINKCONG;
883 }
884
885 /**
886 * link_prepare_wakeup - prepare users for wakeup after congestion
887 * @l: congested link
888 * Wake up a number of waiting users, as permitted by available space
889 * in the send queue
890 */
link_prepare_wakeup(struct tipc_link * l)891 static void link_prepare_wakeup(struct tipc_link *l)
892 {
893 struct sk_buff_head *wakeupq = &l->wakeupq;
894 struct sk_buff_head *inputq = l->inputq;
895 struct sk_buff *skb, *tmp;
896 struct sk_buff_head tmpq;
897 int avail[5] = {0,};
898 int imp = 0;
899
900 __skb_queue_head_init(&tmpq);
901
902 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
903 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
904
905 skb_queue_walk_safe(wakeupq, skb, tmp) {
906 imp = TIPC_SKB_CB(skb)->chain_imp;
907 if (avail[imp] <= 0)
908 continue;
909 avail[imp]--;
910 __skb_unlink(skb, wakeupq);
911 __skb_queue_tail(&tmpq, skb);
912 }
913
914 spin_lock_bh(&inputq->lock);
915 skb_queue_splice_tail(&tmpq, inputq);
916 spin_unlock_bh(&inputq->lock);
917
918 }
919
920 /**
921 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
922 * the given skb should be next attempted
923 * @skb: skb to set a future retransmission time for
924 * @l: link the skb will be transmitted on
925 */
tipc_link_set_skb_retransmit_time(struct sk_buff * skb,struct tipc_link * l)926 static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
927 struct tipc_link *l)
928 {
929 if (link_is_bc_sndlink(l))
930 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
931 else
932 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
933 }
934
tipc_link_reset(struct tipc_link * l)935 void tipc_link_reset(struct tipc_link *l)
936 {
937 struct sk_buff_head list;
938 u32 imp;
939
940 __skb_queue_head_init(&list);
941
942 l->in_session = false;
943 /* Force re-synch of peer session number before establishing */
944 l->peer_session--;
945 l->session++;
946 l->mtu = l->advertised_mtu;
947
948 spin_lock_bh(&l->wakeupq.lock);
949 skb_queue_splice_init(&l->wakeupq, &list);
950 spin_unlock_bh(&l->wakeupq.lock);
951
952 spin_lock_bh(&l->inputq->lock);
953 skb_queue_splice_init(&list, l->inputq);
954 spin_unlock_bh(&l->inputq->lock);
955
956 __skb_queue_purge(&l->transmq);
957 __skb_queue_purge(&l->deferdq);
958 __skb_queue_purge(&l->backlogq);
959 __skb_queue_purge(&l->failover_deferdq);
960 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
961 l->backlog[imp].len = 0;
962 l->backlog[imp].target_bskb = NULL;
963 }
964 kfree_skb(l->reasm_buf);
965 kfree_skb(l->reasm_tnlmsg);
966 kfree_skb(l->failover_reasm_skb);
967 l->reasm_buf = NULL;
968 l->reasm_tnlmsg = NULL;
969 l->failover_reasm_skb = NULL;
970 l->rcv_unacked = 0;
971 l->snd_nxt = 1;
972 l->rcv_nxt = 1;
973 l->snd_nxt_state = 1;
974 l->rcv_nxt_state = 1;
975 l->acked = 0;
976 l->last_gap = 0;
977 kfree(l->last_ga);
978 l->last_ga = NULL;
979 l->silent_intv_cnt = 0;
980 l->rst_cnt = 0;
981 l->bc_peer_is_up = false;
982 memset(&l->mon_state, 0, sizeof(l->mon_state));
983 tipc_link_reset_stats(l);
984 }
985
986 /**
987 * tipc_link_xmit(): enqueue buffer list according to queue situation
988 * @l: link to use
989 * @list: chain of buffers containing message
990 * @xmitq: returned list of packets to be sent by caller
991 *
992 * Consumes the buffer chain.
993 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
994 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
995 */
tipc_link_xmit(struct tipc_link * l,struct sk_buff_head * list,struct sk_buff_head * xmitq)996 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
997 struct sk_buff_head *xmitq)
998 {
999 struct sk_buff_head *backlogq = &l->backlogq;
1000 struct sk_buff_head *transmq = &l->transmq;
1001 struct sk_buff *skb, *_skb;
1002 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1003 u16 ack = l->rcv_nxt - 1;
1004 u16 seqno = l->snd_nxt;
1005 int pkt_cnt = skb_queue_len(list);
1006 unsigned int mss = tipc_link_mss(l);
1007 unsigned int cwin = l->window;
1008 unsigned int mtu = l->mtu;
1009 struct tipc_msg *hdr;
1010 bool new_bundle;
1011 int rc = 0;
1012 int imp;
1013
1014 if (pkt_cnt <= 0)
1015 return 0;
1016
1017 hdr = buf_msg(skb_peek(list));
1018 if (unlikely(msg_size(hdr) > mtu)) {
1019 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1020 skb_queue_len(list), msg_user(hdr),
1021 msg_type(hdr), msg_size(hdr), mtu);
1022 __skb_queue_purge(list);
1023 return -EMSGSIZE;
1024 }
1025
1026 imp = msg_importance(hdr);
1027 /* Allow oversubscription of one data msg per source at congestion */
1028 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1029 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1030 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1031 return -ENOBUFS;
1032 }
1033 rc = link_schedule_user(l, hdr);
1034 }
1035
1036 if (pkt_cnt > 1) {
1037 l->stats.sent_fragmented++;
1038 l->stats.sent_fragments += pkt_cnt;
1039 }
1040
1041 /* Prepare each packet for sending, and add to relevant queue: */
1042 while ((skb = __skb_dequeue(list))) {
1043 if (likely(skb_queue_len(transmq) < cwin)) {
1044 hdr = buf_msg(skb);
1045 msg_set_seqno(hdr, seqno);
1046 msg_set_ack(hdr, ack);
1047 msg_set_bcast_ack(hdr, bc_ack);
1048 _skb = skb_clone(skb, GFP_ATOMIC);
1049 if (!_skb) {
1050 kfree_skb(skb);
1051 __skb_queue_purge(list);
1052 return -ENOBUFS;
1053 }
1054 __skb_queue_tail(transmq, skb);
1055 tipc_link_set_skb_retransmit_time(skb, l);
1056 __skb_queue_tail(xmitq, _skb);
1057 TIPC_SKB_CB(skb)->ackers = l->ackers;
1058 l->rcv_unacked = 0;
1059 l->stats.sent_pkts++;
1060 seqno++;
1061 continue;
1062 }
1063 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1064 mss, l->addr, &new_bundle)) {
1065 if (skb) {
1066 /* Keep a ref. to the skb for next try */
1067 l->backlog[imp].target_bskb = skb;
1068 l->backlog[imp].len++;
1069 __skb_queue_tail(backlogq, skb);
1070 } else {
1071 if (new_bundle) {
1072 l->stats.sent_bundles++;
1073 l->stats.sent_bundled++;
1074 }
1075 l->stats.sent_bundled++;
1076 }
1077 continue;
1078 }
1079 l->backlog[imp].target_bskb = NULL;
1080 l->backlog[imp].len += (1 + skb_queue_len(list));
1081 __skb_queue_tail(backlogq, skb);
1082 skb_queue_splice_tail_init(list, backlogq);
1083 }
1084 l->snd_nxt = seqno;
1085 return rc;
1086 }
1087
tipc_link_update_cwin(struct tipc_link * l,int released,bool retransmitted)1088 static void tipc_link_update_cwin(struct tipc_link *l, int released,
1089 bool retransmitted)
1090 {
1091 int bklog_len = skb_queue_len(&l->backlogq);
1092 struct sk_buff_head *txq = &l->transmq;
1093 int txq_len = skb_queue_len(txq);
1094 u16 cwin = l->window;
1095
1096 /* Enter fast recovery */
1097 if (unlikely(retransmitted)) {
1098 l->ssthresh = max_t(u16, l->window / 2, 300);
1099 l->window = min_t(u16, l->ssthresh, l->window);
1100 return;
1101 }
1102 /* Enter slow start */
1103 if (unlikely(!released)) {
1104 l->ssthresh = max_t(u16, l->window / 2, 300);
1105 l->window = l->min_win;
1106 return;
1107 }
1108 /* Don't increase window if no pressure on the transmit queue */
1109 if (txq_len + bklog_len < cwin)
1110 return;
1111
1112 /* Don't increase window if there are holes the transmit queue */
1113 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1114 return;
1115
1116 l->cong_acks += released;
1117
1118 /* Slow start */
1119 if (cwin <= l->ssthresh) {
1120 l->window = min_t(u16, cwin + released, l->max_win);
1121 return;
1122 }
1123 /* Congestion avoidance */
1124 if (l->cong_acks < cwin)
1125 return;
1126 l->window = min_t(u16, ++cwin, l->max_win);
1127 l->cong_acks = 0;
1128 }
1129
tipc_link_advance_backlog(struct tipc_link * l,struct sk_buff_head * xmitq)1130 static void tipc_link_advance_backlog(struct tipc_link *l,
1131 struct sk_buff_head *xmitq)
1132 {
1133 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1134 struct sk_buff_head *txq = &l->transmq;
1135 struct sk_buff *skb, *_skb;
1136 u16 ack = l->rcv_nxt - 1;
1137 u16 seqno = l->snd_nxt;
1138 struct tipc_msg *hdr;
1139 u16 cwin = l->window;
1140 u32 imp;
1141
1142 while (skb_queue_len(txq) < cwin) {
1143 skb = skb_peek(&l->backlogq);
1144 if (!skb)
1145 break;
1146 _skb = skb_clone(skb, GFP_ATOMIC);
1147 if (!_skb)
1148 break;
1149 __skb_dequeue(&l->backlogq);
1150 hdr = buf_msg(skb);
1151 imp = msg_importance(hdr);
1152 l->backlog[imp].len--;
1153 if (unlikely(skb == l->backlog[imp].target_bskb))
1154 l->backlog[imp].target_bskb = NULL;
1155 __skb_queue_tail(&l->transmq, skb);
1156 tipc_link_set_skb_retransmit_time(skb, l);
1157
1158 __skb_queue_tail(xmitq, _skb);
1159 TIPC_SKB_CB(skb)->ackers = l->ackers;
1160 msg_set_seqno(hdr, seqno);
1161 msg_set_ack(hdr, ack);
1162 msg_set_bcast_ack(hdr, bc_ack);
1163 l->rcv_unacked = 0;
1164 l->stats.sent_pkts++;
1165 seqno++;
1166 }
1167 l->snd_nxt = seqno;
1168 }
1169
1170 /**
1171 * link_retransmit_failure() - Detect repeated retransmit failures
1172 * @l: tipc link sender
1173 * @r: tipc link receiver (= l in case of unicast)
1174 * @rc: returned code
1175 *
1176 * Return: true if the repeated retransmit failures happens, otherwise
1177 * false
1178 */
link_retransmit_failure(struct tipc_link * l,struct tipc_link * r,int * rc)1179 static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1180 int *rc)
1181 {
1182 struct sk_buff *skb = skb_peek(&l->transmq);
1183 struct tipc_msg *hdr;
1184
1185 if (!skb)
1186 return false;
1187
1188 if (!TIPC_SKB_CB(skb)->retr_cnt)
1189 return false;
1190
1191 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1192 msecs_to_jiffies(r->tolerance * 10)))
1193 return false;
1194
1195 hdr = buf_msg(skb);
1196 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1197 return false;
1198
1199 pr_warn("Retransmission failure on link <%s>\n", l->name);
1200 link_print(l, "State of link ");
1201 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1202 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1203 pr_info("sqno %u, prev: %x, dest: %x\n",
1204 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1205 pr_info("retr_stamp %d, retr_cnt %d\n",
1206 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1207 TIPC_SKB_CB(skb)->retr_cnt);
1208
1209 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1210 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1211 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1212
1213 if (link_is_bc_sndlink(l)) {
1214 r->state = LINK_RESET;
1215 *rc |= TIPC_LINK_DOWN_EVT;
1216 } else {
1217 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1218 }
1219
1220 return true;
1221 }
1222
1223 /* tipc_data_input - deliver data and name distr msgs to upper layer
1224 *
1225 * Consumes buffer if message is of right type
1226 * Node lock must be held
1227 */
tipc_data_input(struct tipc_link * l,struct sk_buff * skb,struct sk_buff_head * inputq)1228 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1229 struct sk_buff_head *inputq)
1230 {
1231 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1232 struct tipc_msg *hdr = buf_msg(skb);
1233
1234 switch (msg_user(hdr)) {
1235 case TIPC_LOW_IMPORTANCE:
1236 case TIPC_MEDIUM_IMPORTANCE:
1237 case TIPC_HIGH_IMPORTANCE:
1238 case TIPC_CRITICAL_IMPORTANCE:
1239 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1240 skb_queue_tail(mc_inputq, skb);
1241 return true;
1242 }
1243 fallthrough;
1244 case CONN_MANAGER:
1245 skb_queue_tail(inputq, skb);
1246 return true;
1247 case GROUP_PROTOCOL:
1248 skb_queue_tail(mc_inputq, skb);
1249 return true;
1250 case NAME_DISTRIBUTOR:
1251 l->bc_rcvlink->state = LINK_ESTABLISHED;
1252 skb_queue_tail(l->namedq, skb);
1253 return true;
1254 case MSG_BUNDLER:
1255 case TUNNEL_PROTOCOL:
1256 case MSG_FRAGMENTER:
1257 case BCAST_PROTOCOL:
1258 return false;
1259 #ifdef CONFIG_TIPC_CRYPTO
1260 case MSG_CRYPTO:
1261 tipc_crypto_msg_rcv(l->net, skb);
1262 return true;
1263 #endif
1264 default:
1265 pr_warn("Dropping received illegal msg type\n");
1266 kfree_skb(skb);
1267 return true;
1268 };
1269 }
1270
1271 /* tipc_link_input - process packet that has passed link protocol check
1272 *
1273 * Consumes buffer
1274 */
tipc_link_input(struct tipc_link * l,struct sk_buff * skb,struct sk_buff_head * inputq,struct sk_buff ** reasm_skb)1275 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1276 struct sk_buff_head *inputq,
1277 struct sk_buff **reasm_skb)
1278 {
1279 struct tipc_msg *hdr = buf_msg(skb);
1280 struct sk_buff *iskb;
1281 struct sk_buff_head tmpq;
1282 int usr = msg_user(hdr);
1283 int pos = 0;
1284
1285 if (usr == MSG_BUNDLER) {
1286 skb_queue_head_init(&tmpq);
1287 l->stats.recv_bundles++;
1288 l->stats.recv_bundled += msg_msgcnt(hdr);
1289 while (tipc_msg_extract(skb, &iskb, &pos))
1290 tipc_data_input(l, iskb, &tmpq);
1291 tipc_skb_queue_splice_tail(&tmpq, inputq);
1292 return 0;
1293 } else if (usr == MSG_FRAGMENTER) {
1294 l->stats.recv_fragments++;
1295 if (tipc_buf_append(reasm_skb, &skb)) {
1296 l->stats.recv_fragmented++;
1297 tipc_data_input(l, skb, inputq);
1298 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1299 pr_warn_ratelimited("Unable to build fragment list\n");
1300 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1301 }
1302 return 0;
1303 } else if (usr == BCAST_PROTOCOL) {
1304 tipc_bcast_lock(l->net);
1305 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1306 tipc_bcast_unlock(l->net);
1307 }
1308
1309 kfree_skb(skb);
1310 return 0;
1311 }
1312
1313 /* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1314 * inner message along with the ones in the old link's
1315 * deferdq
1316 * @l: tunnel link
1317 * @skb: TUNNEL_PROTOCOL message
1318 * @inputq: queue to put messages ready for delivery
1319 */
tipc_link_tnl_rcv(struct tipc_link * l,struct sk_buff * skb,struct sk_buff_head * inputq)1320 static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1321 struct sk_buff_head *inputq)
1322 {
1323 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1324 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1325 struct sk_buff_head *fdefq = &l->failover_deferdq;
1326 struct tipc_msg *hdr = buf_msg(skb);
1327 struct sk_buff *iskb;
1328 int ipos = 0;
1329 int rc = 0;
1330 u16 seqno;
1331
1332 if (msg_type(hdr) == SYNCH_MSG) {
1333 kfree_skb(skb);
1334 return 0;
1335 }
1336
1337 /* Not a fragment? */
1338 if (likely(!msg_nof_fragms(hdr))) {
1339 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1340 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1341 skb_queue_len(fdefq));
1342 return 0;
1343 }
1344 kfree_skb(skb);
1345 } else {
1346 /* Set fragment type for buf_append */
1347 if (msg_fragm_no(hdr) == 1)
1348 msg_set_type(hdr, FIRST_FRAGMENT);
1349 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1350 msg_set_type(hdr, FRAGMENT);
1351 else
1352 msg_set_type(hdr, LAST_FRAGMENT);
1353
1354 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1355 /* Successful but non-complete reassembly? */
1356 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1357 return 0;
1358 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1359 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1360 }
1361 iskb = skb;
1362 }
1363
1364 do {
1365 seqno = buf_seqno(iskb);
1366 if (unlikely(less(seqno, l->drop_point))) {
1367 kfree_skb(iskb);
1368 continue;
1369 }
1370 if (unlikely(seqno != l->drop_point)) {
1371 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1372 continue;
1373 }
1374
1375 l->drop_point++;
1376 if (!tipc_data_input(l, iskb, inputq))
1377 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1378 if (unlikely(rc))
1379 break;
1380 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1381
1382 return rc;
1383 }
1384
1385 /**
1386 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1387 * @ga: returned pointer to the Gap ACK blocks if any
1388 * @l: the tipc link
1389 * @hdr: the PROTOCOL/STATE_MSG header
1390 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1391 *
1392 * Return: the total Gap ACK blocks size
1393 */
tipc_get_gap_ack_blks(struct tipc_gap_ack_blks ** ga,struct tipc_link * l,struct tipc_msg * hdr,bool uc)1394 u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1395 struct tipc_msg *hdr, bool uc)
1396 {
1397 struct tipc_gap_ack_blks *p;
1398 u16 sz = 0;
1399
1400 /* Does peer support the Gap ACK blocks feature? */
1401 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1402 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1403 sz = ntohs(p->len);
1404 /* Sanity check */
1405 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1406 /* Good, check if the desired type exists */
1407 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1408 goto ok;
1409 /* Backward compatible: peer might not support bc, but uc? */
1410 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1411 if (p->ugack_cnt) {
1412 p->bgack_cnt = 0;
1413 goto ok;
1414 }
1415 }
1416 }
1417 /* Other cases: ignore! */
1418 p = NULL;
1419
1420 ok:
1421 *ga = p;
1422 return sz;
1423 }
1424
__tipc_build_gap_ack_blks(struct tipc_gap_ack_blks * ga,struct tipc_link * l,u8 start_index)1425 static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1426 struct tipc_link *l, u8 start_index)
1427 {
1428 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1429 struct sk_buff *skb = skb_peek(&l->deferdq);
1430 u16 expect, seqno = 0;
1431 u8 n = 0;
1432
1433 if (!skb)
1434 return 0;
1435
1436 expect = buf_seqno(skb);
1437 skb_queue_walk(&l->deferdq, skb) {
1438 seqno = buf_seqno(skb);
1439 if (unlikely(more(seqno, expect))) {
1440 gacks[n].ack = htons(expect - 1);
1441 gacks[n].gap = htons(seqno - expect);
1442 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1443 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1444 l->name, n,
1445 skb_queue_len(&l->deferdq));
1446 return n;
1447 }
1448 } else if (unlikely(less(seqno, expect))) {
1449 pr_warn("Unexpected skb in deferdq!\n");
1450 continue;
1451 }
1452 expect = seqno + 1;
1453 }
1454
1455 /* last block */
1456 gacks[n].ack = htons(seqno);
1457 gacks[n].gap = 0;
1458 n++;
1459 return n;
1460 }
1461
1462 /* tipc_build_gap_ack_blks - build Gap ACK blocks
1463 * @l: tipc unicast link
1464 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1465 *
1466 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1467 * links of a certain peer, the buffer after built has the network data format
1468 * as found at the struct tipc_gap_ack_blks definition.
1469 *
1470 * returns the actual allocated memory size
1471 */
tipc_build_gap_ack_blks(struct tipc_link * l,struct tipc_msg * hdr)1472 static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1473 {
1474 struct tipc_link *bcl = l->bc_rcvlink;
1475 struct tipc_gap_ack_blks *ga;
1476 u16 len;
1477
1478 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1479
1480 /* Start with broadcast link first */
1481 tipc_bcast_lock(bcl->net);
1482 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1483 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1484 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1485 tipc_bcast_unlock(bcl->net);
1486
1487 /* Now for unicast link, but an explicit NACK only (???) */
1488 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1489 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1490
1491 /* Total len */
1492 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1493 ga->len = htons(len);
1494 return len;
1495 }
1496
1497 /* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1498 * acked packets, also doing retransmissions if
1499 * gaps found
1500 * @l: tipc link with transmq queue to be advanced
1501 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1502 * @acked: seqno of last packet acked by peer without any gaps before
1503 * @gap: # of gap packets
1504 * @ga: buffer pointer to Gap ACK blocks from peer
1505 * @xmitq: queue for accumulating the retransmitted packets if any
1506 * @retransmitted: returned boolean value if a retransmission is really issued
1507 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1508 * happens (- unlikely case)
1509 *
1510 * Return: the number of packets released from the link transmq
1511 */
tipc_link_advance_transmq(struct tipc_link * l,struct tipc_link * r,u16 acked,u16 gap,struct tipc_gap_ack_blks * ga,struct sk_buff_head * xmitq,bool * retransmitted,int * rc)1512 static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1513 u16 acked, u16 gap,
1514 struct tipc_gap_ack_blks *ga,
1515 struct sk_buff_head *xmitq,
1516 bool *retransmitted, int *rc)
1517 {
1518 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1519 struct tipc_gap_ack *gacks = NULL;
1520 struct sk_buff *skb, *_skb, *tmp;
1521 struct tipc_msg *hdr;
1522 u32 qlen = skb_queue_len(&l->transmq);
1523 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1524 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1525 u16 ack = l->rcv_nxt - 1;
1526 u16 seqno, n = 0;
1527 u16 end = r->acked, start = end, offset = r->last_gap;
1528 u16 si = (last_ga) ? last_ga->start_index : 0;
1529 bool is_uc = !link_is_bc_sndlink(l);
1530 bool bc_has_acked = false;
1531
1532 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1533
1534 /* Determine Gap ACK blocks if any for the particular link */
1535 if (ga && is_uc) {
1536 /* Get the Gap ACKs, uc part */
1537 gack_cnt = ga->ugack_cnt;
1538 gacks = &ga->gacks[ga->bgack_cnt];
1539 } else if (ga) {
1540 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1541 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1542 GFP_ATOMIC);
1543 if (likely(this_ga)) {
1544 this_ga->start_index = 0;
1545 /* Start with the bc Gap ACKs */
1546 gack_cnt = this_ga->bgack_cnt;
1547 gacks = &this_ga->gacks[0];
1548 } else {
1549 /* Hmm, we can get in trouble..., simply ignore it */
1550 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1551 }
1552 }
1553
1554 /* Advance the link transmq */
1555 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1556 seqno = buf_seqno(skb);
1557
1558 next_gap_ack:
1559 if (less_eq(seqno, nacked)) {
1560 if (is_uc)
1561 goto release;
1562 /* Skip packets peer has already acked */
1563 if (!more(seqno, r->acked))
1564 continue;
1565 /* Get the next of last Gap ACK blocks */
1566 while (more(seqno, end)) {
1567 if (!last_ga || si >= last_ga->bgack_cnt)
1568 break;
1569 start = end + offset + 1;
1570 end = ntohs(last_ga->gacks[si].ack);
1571 offset = ntohs(last_ga->gacks[si].gap);
1572 si++;
1573 WARN_ONCE(more(start, end) ||
1574 (!offset &&
1575 si < last_ga->bgack_cnt) ||
1576 si > MAX_GAP_ACK_BLKS,
1577 "Corrupted Gap ACK: %d %d %d %d %d\n",
1578 start, end, offset, si,
1579 last_ga->bgack_cnt);
1580 }
1581 /* Check against the last Gap ACK block */
1582 if (in_range(seqno, start, end))
1583 continue;
1584 /* Update/release the packet peer is acking */
1585 bc_has_acked = true;
1586 if (--TIPC_SKB_CB(skb)->ackers)
1587 continue;
1588 release:
1589 /* release skb */
1590 __skb_unlink(skb, &l->transmq);
1591 kfree_skb(skb);
1592 } else if (less_eq(seqno, nacked + ngap)) {
1593 /* First gap: check if repeated retrans failures? */
1594 if (unlikely(seqno == acked + 1 &&
1595 link_retransmit_failure(l, r, rc))) {
1596 /* Ignore this bc Gap ACKs if any */
1597 kfree(this_ga);
1598 this_ga = NULL;
1599 break;
1600 }
1601 /* retransmit skb if unrestricted*/
1602 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1603 continue;
1604 tipc_link_set_skb_retransmit_time(skb, l);
1605 _skb = pskb_copy(skb, GFP_ATOMIC);
1606 if (!_skb)
1607 continue;
1608 hdr = buf_msg(_skb);
1609 msg_set_ack(hdr, ack);
1610 msg_set_bcast_ack(hdr, bc_ack);
1611 _skb->priority = TC_PRIO_CONTROL;
1612 __skb_queue_tail(xmitq, _skb);
1613 l->stats.retransmitted++;
1614 if (!is_uc)
1615 r->stats.retransmitted++;
1616 *retransmitted = true;
1617 /* Increase actual retrans counter & mark first time */
1618 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1619 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1620 } else {
1621 /* retry with Gap ACK blocks if any */
1622 if (n >= gack_cnt)
1623 break;
1624 nacked = ntohs(gacks[n].ack);
1625 ngap = ntohs(gacks[n].gap);
1626 n++;
1627 goto next_gap_ack;
1628 }
1629 }
1630
1631 /* Renew last Gap ACK blocks for bc if needed */
1632 if (bc_has_acked) {
1633 if (this_ga) {
1634 kfree(last_ga);
1635 r->last_ga = this_ga;
1636 r->last_gap = gap;
1637 } else if (last_ga) {
1638 if (less(acked, start)) {
1639 si--;
1640 offset = start - acked - 1;
1641 } else if (less(acked, end)) {
1642 acked = end;
1643 }
1644 if (si < last_ga->bgack_cnt) {
1645 last_ga->start_index = si;
1646 r->last_gap = offset;
1647 } else {
1648 kfree(last_ga);
1649 r->last_ga = NULL;
1650 r->last_gap = 0;
1651 }
1652 } else {
1653 r->last_gap = 0;
1654 }
1655 r->acked = acked;
1656 } else {
1657 kfree(this_ga);
1658 }
1659
1660 return qlen - skb_queue_len(&l->transmq);
1661 }
1662
1663 /* tipc_link_build_state_msg: prepare link state message for transmission
1664 *
1665 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1666 * risk of ack storms towards the sender
1667 */
tipc_link_build_state_msg(struct tipc_link * l,struct sk_buff_head * xmitq)1668 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1669 {
1670 if (!l)
1671 return 0;
1672
1673 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1674 if (link_is_bc_rcvlink(l)) {
1675 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1676 return 0;
1677 l->rcv_unacked = 0;
1678
1679 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1680 l->snd_nxt = l->rcv_nxt;
1681 return TIPC_LINK_SND_STATE;
1682 }
1683 /* Unicast ACK */
1684 l->rcv_unacked = 0;
1685 l->stats.sent_acks++;
1686 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1687 return 0;
1688 }
1689
1690 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1691 */
tipc_link_build_reset_msg(struct tipc_link * l,struct sk_buff_head * xmitq)1692 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1693 {
1694 int mtyp = RESET_MSG;
1695 struct sk_buff *skb;
1696
1697 if (l->state == LINK_ESTABLISHING)
1698 mtyp = ACTIVATE_MSG;
1699
1700 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1701
1702 /* Inform peer that this endpoint is going down if applicable */
1703 skb = skb_peek_tail(xmitq);
1704 if (skb && (l->state == LINK_RESET))
1705 msg_set_peer_stopping(buf_msg(skb), 1);
1706 }
1707
1708 /* tipc_link_build_nack_msg: prepare link nack message for transmission
1709 * Note that sending of broadcast NACK is coordinated among nodes, to
1710 * reduce the risk of NACK storms towards the sender
1711 */
tipc_link_build_nack_msg(struct tipc_link * l,struct sk_buff_head * xmitq)1712 static int tipc_link_build_nack_msg(struct tipc_link *l,
1713 struct sk_buff_head *xmitq)
1714 {
1715 u32 def_cnt = ++l->stats.deferred_recv;
1716 struct sk_buff_head *dfq = &l->deferdq;
1717 u32 defq_len = skb_queue_len(dfq);
1718 int match1, match2;
1719
1720 if (link_is_bc_rcvlink(l)) {
1721 match1 = def_cnt & 0xf;
1722 match2 = tipc_own_addr(l->net) & 0xf;
1723 if (match1 == match2)
1724 return TIPC_LINK_SND_STATE;
1725 return 0;
1726 }
1727
1728 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1729 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1730
1731 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1732 rcvgap, 0, 0, xmitq);
1733 }
1734 return 0;
1735 }
1736
1737 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1738 * @l: the link that should handle the message
1739 * @skb: TIPC packet
1740 * @xmitq: queue to place packets to be sent after this call
1741 */
tipc_link_rcv(struct tipc_link * l,struct sk_buff * skb,struct sk_buff_head * xmitq)1742 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1743 struct sk_buff_head *xmitq)
1744 {
1745 struct sk_buff_head *defq = &l->deferdq;
1746 struct tipc_msg *hdr = buf_msg(skb);
1747 u16 seqno, rcv_nxt, win_lim;
1748 int released = 0;
1749 int rc = 0;
1750
1751 /* Verify and update link state */
1752 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1753 return tipc_link_proto_rcv(l, skb, xmitq);
1754
1755 /* Don't send probe at next timeout expiration */
1756 l->silent_intv_cnt = 0;
1757
1758 do {
1759 hdr = buf_msg(skb);
1760 seqno = msg_seqno(hdr);
1761 rcv_nxt = l->rcv_nxt;
1762 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1763
1764 if (unlikely(!link_is_up(l))) {
1765 if (l->state == LINK_ESTABLISHING)
1766 rc = TIPC_LINK_UP_EVT;
1767 kfree_skb(skb);
1768 break;
1769 }
1770
1771 /* Drop if outside receive window */
1772 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1773 l->stats.duplicates++;
1774 kfree_skb(skb);
1775 break;
1776 }
1777 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1778 NULL, NULL, NULL, NULL);
1779
1780 /* Defer delivery if sequence gap */
1781 if (unlikely(seqno != rcv_nxt)) {
1782 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1783 l->stats.duplicates++;
1784 rc |= tipc_link_build_nack_msg(l, xmitq);
1785 break;
1786 }
1787
1788 /* Deliver packet */
1789 l->rcv_nxt++;
1790 l->stats.recv_pkts++;
1791
1792 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1793 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1794 else if (!tipc_data_input(l, skb, l->inputq))
1795 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1796 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1797 rc |= tipc_link_build_state_msg(l, xmitq);
1798 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1799 break;
1800 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1801
1802 /* Forward queues and wake up waiting users */
1803 if (released) {
1804 tipc_link_update_cwin(l, released, 0);
1805 tipc_link_advance_backlog(l, xmitq);
1806 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1807 link_prepare_wakeup(l);
1808 }
1809 return rc;
1810 }
1811
tipc_link_build_proto_msg(struct tipc_link * l,int mtyp,bool probe,bool probe_reply,u16 rcvgap,int tolerance,int priority,struct sk_buff_head * xmitq)1812 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1813 bool probe_reply, u16 rcvgap,
1814 int tolerance, int priority,
1815 struct sk_buff_head *xmitq)
1816 {
1817 struct tipc_mon_state *mstate = &l->mon_state;
1818 struct sk_buff_head *dfq = &l->deferdq;
1819 struct tipc_link *bcl = l->bc_rcvlink;
1820 struct tipc_msg *hdr;
1821 struct sk_buff *skb;
1822 bool node_up = link_is_up(bcl);
1823 u16 glen = 0, bc_rcvgap = 0;
1824 int dlen = 0;
1825 void *data;
1826
1827 /* Don't send protocol message during reset or link failover */
1828 if (tipc_link_is_blocked(l))
1829 return;
1830
1831 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1832 return;
1833
1834 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1835 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1836
1837 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1838 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1839 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1840 if (!skb)
1841 return;
1842
1843 hdr = buf_msg(skb);
1844 data = msg_data(hdr);
1845 msg_set_session(hdr, l->session);
1846 msg_set_bearer_id(hdr, l->bearer_id);
1847 msg_set_net_plane(hdr, l->net_plane);
1848 msg_set_next_sent(hdr, l->snd_nxt);
1849 msg_set_ack(hdr, l->rcv_nxt - 1);
1850 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1851 msg_set_bc_ack_invalid(hdr, !node_up);
1852 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1853 msg_set_link_tolerance(hdr, tolerance);
1854 msg_set_linkprio(hdr, priority);
1855 msg_set_redundant_link(hdr, node_up);
1856 msg_set_seq_gap(hdr, 0);
1857 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1858
1859 if (mtyp == STATE_MSG) {
1860 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1861 msg_set_seqno(hdr, l->snd_nxt_state++);
1862 msg_set_seq_gap(hdr, rcvgap);
1863 bc_rcvgap = link_bc_rcv_gap(bcl);
1864 msg_set_bc_gap(hdr, bc_rcvgap);
1865 msg_set_probe(hdr, probe);
1866 msg_set_is_keepalive(hdr, probe || probe_reply);
1867 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1868 glen = tipc_build_gap_ack_blks(l, hdr);
1869 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1870 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1871 skb_trim(skb, INT_H_SIZE + glen + dlen);
1872 l->stats.sent_states++;
1873 l->rcv_unacked = 0;
1874 } else {
1875 /* RESET_MSG or ACTIVATE_MSG */
1876 if (mtyp == ACTIVATE_MSG) {
1877 msg_set_dest_session_valid(hdr, 1);
1878 msg_set_dest_session(hdr, l->peer_session);
1879 }
1880 msg_set_max_pkt(hdr, l->advertised_mtu);
1881 strcpy(data, l->if_name);
1882 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1883 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1884 }
1885 if (probe)
1886 l->stats.sent_probes++;
1887 if (rcvgap)
1888 l->stats.sent_nacks++;
1889 if (bc_rcvgap)
1890 bcl->stats.sent_nacks++;
1891 skb->priority = TC_PRIO_CONTROL;
1892 __skb_queue_tail(xmitq, skb);
1893 trace_tipc_proto_build(skb, false, l->name);
1894 }
1895
tipc_link_create_dummy_tnl_msg(struct tipc_link * l,struct sk_buff_head * xmitq)1896 void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1897 struct sk_buff_head *xmitq)
1898 {
1899 u32 onode = tipc_own_addr(l->net);
1900 struct tipc_msg *hdr, *ihdr;
1901 struct sk_buff_head tnlq;
1902 struct sk_buff *skb;
1903 u32 dnode = l->addr;
1904
1905 __skb_queue_head_init(&tnlq);
1906 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1907 INT_H_SIZE, BASIC_H_SIZE,
1908 dnode, onode, 0, 0, 0);
1909 if (!skb) {
1910 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1911 return;
1912 }
1913
1914 hdr = buf_msg(skb);
1915 msg_set_msgcnt(hdr, 1);
1916 msg_set_bearer_id(hdr, l->peer_bearer_id);
1917
1918 ihdr = (struct tipc_msg *)msg_data(hdr);
1919 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1920 BASIC_H_SIZE, dnode);
1921 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1922 __skb_queue_tail(&tnlq, skb);
1923 tipc_link_xmit(l, &tnlq, xmitq);
1924 }
1925
1926 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1927 * with contents of the link's transmit and backlog queues.
1928 */
tipc_link_tnl_prepare(struct tipc_link * l,struct tipc_link * tnl,int mtyp,struct sk_buff_head * xmitq)1929 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1930 int mtyp, struct sk_buff_head *xmitq)
1931 {
1932 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1933 struct sk_buff *skb, *tnlskb;
1934 struct tipc_msg *hdr, tnlhdr;
1935 struct sk_buff_head *queue = &l->transmq;
1936 struct sk_buff_head tmpxq, tnlq, frags;
1937 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1938 bool pktcnt_need_update = false;
1939 u16 syncpt;
1940 int rc;
1941
1942 if (!tnl)
1943 return;
1944
1945 __skb_queue_head_init(&tnlq);
1946 /* Link Synching:
1947 * From now on, send only one single ("dummy") SYNCH message
1948 * to peer. The SYNCH message does not contain any data, just
1949 * a header conveying the synch point to the peer.
1950 */
1951 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1952 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1953 INT_H_SIZE, 0, l->addr,
1954 tipc_own_addr(l->net),
1955 0, 0, 0);
1956 if (!tnlskb) {
1957 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1958 link_co_err);
1959 return;
1960 }
1961
1962 hdr = buf_msg(tnlskb);
1963 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1964 msg_set_syncpt(hdr, syncpt);
1965 msg_set_bearer_id(hdr, l->peer_bearer_id);
1966 __skb_queue_tail(&tnlq, tnlskb);
1967 tipc_link_xmit(tnl, &tnlq, xmitq);
1968 return;
1969 }
1970
1971 __skb_queue_head_init(&tmpxq);
1972 __skb_queue_head_init(&frags);
1973 /* At least one packet required for safe algorithm => add dummy */
1974 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1975 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1976 0, 0, TIPC_ERR_NO_PORT);
1977 if (!skb) {
1978 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1979 return;
1980 }
1981 __skb_queue_tail(&tnlq, skb);
1982 tipc_link_xmit(l, &tnlq, &tmpxq);
1983 __skb_queue_purge(&tmpxq);
1984
1985 /* Initialize reusable tunnel packet header */
1986 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1987 mtyp, INT_H_SIZE, l->addr);
1988 if (mtyp == SYNCH_MSG)
1989 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
1990 else
1991 pktcnt = skb_queue_len(&l->transmq);
1992 pktcnt += skb_queue_len(&l->backlogq);
1993 msg_set_msgcnt(&tnlhdr, pktcnt);
1994 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1995 tnl:
1996 /* Wrap each packet into a tunnel packet */
1997 skb_queue_walk(queue, skb) {
1998 hdr = buf_msg(skb);
1999 if (queue == &l->backlogq)
2000 msg_set_seqno(hdr, seqno++);
2001 pktlen = msg_size(hdr);
2002
2003 /* Tunnel link MTU is not large enough? This could be
2004 * due to:
2005 * 1) Link MTU has just changed or set differently;
2006 * 2) Or FAILOVER on the top of a SYNCH message
2007 *
2008 * The 2nd case should not happen if peer supports
2009 * TIPC_TUNNEL_ENHANCED
2010 */
2011 if (pktlen > tnl->mtu - INT_H_SIZE) {
2012 if (mtyp == FAILOVER_MSG &&
2013 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2014 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2015 &frags);
2016 if (rc) {
2017 pr_warn("%sunable to frag msg: rc %d\n",
2018 link_co_err, rc);
2019 return;
2020 }
2021 pktcnt += skb_queue_len(&frags) - 1;
2022 pktcnt_need_update = true;
2023 skb_queue_splice_tail_init(&frags, &tnlq);
2024 continue;
2025 }
2026 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2027 * => Just warn it and return!
2028 */
2029 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2030 link_co_err, msg_user(hdr),
2031 msg_type(hdr), msg_size(hdr));
2032 return;
2033 }
2034
2035 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2036 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2037 if (!tnlskb) {
2038 pr_warn("%sunable to send packet\n", link_co_err);
2039 return;
2040 }
2041 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2042 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2043 __skb_queue_tail(&tnlq, tnlskb);
2044 }
2045 if (queue != &l->backlogq) {
2046 queue = &l->backlogq;
2047 goto tnl;
2048 }
2049
2050 if (pktcnt_need_update)
2051 skb_queue_walk(&tnlq, skb) {
2052 hdr = buf_msg(skb);
2053 msg_set_msgcnt(hdr, pktcnt);
2054 }
2055
2056 tipc_link_xmit(tnl, &tnlq, xmitq);
2057
2058 if (mtyp == FAILOVER_MSG) {
2059 tnl->drop_point = l->rcv_nxt;
2060 tnl->failover_reasm_skb = l->reasm_buf;
2061 l->reasm_buf = NULL;
2062
2063 /* Failover the link's deferdq */
2064 if (unlikely(!skb_queue_empty(fdefq))) {
2065 pr_warn("Link failover deferdq not empty: %d!\n",
2066 skb_queue_len(fdefq));
2067 __skb_queue_purge(fdefq);
2068 }
2069 skb_queue_splice_init(&l->deferdq, fdefq);
2070 }
2071 }
2072
2073 /**
2074 * tipc_link_failover_prepare() - prepare tnl for link failover
2075 *
2076 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2077 * see the tipc_node_link_failover() for details
2078 *
2079 * @l: failover link
2080 * @tnl: tunnel link
2081 * @xmitq: queue for messages to be xmited
2082 */
tipc_link_failover_prepare(struct tipc_link * l,struct tipc_link * tnl,struct sk_buff_head * xmitq)2083 void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2084 struct sk_buff_head *xmitq)
2085 {
2086 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2087
2088 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2089
2090 /* This failover link endpoint was never established before,
2091 * so it has not received anything from peer.
2092 * Otherwise, it must be a normal failover situation or the
2093 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2094 * would have to start over from scratch instead.
2095 */
2096 tnl->drop_point = 1;
2097 tnl->failover_reasm_skb = NULL;
2098
2099 /* Initiate the link's failover deferdq */
2100 if (unlikely(!skb_queue_empty(fdefq))) {
2101 pr_warn("Link failover deferdq not empty: %d!\n",
2102 skb_queue_len(fdefq));
2103 __skb_queue_purge(fdefq);
2104 }
2105 }
2106
2107 /* tipc_link_validate_msg(): validate message against current link state
2108 * Returns true if message should be accepted, otherwise false
2109 */
tipc_link_validate_msg(struct tipc_link * l,struct tipc_msg * hdr)2110 bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2111 {
2112 u16 curr_session = l->peer_session;
2113 u16 session = msg_session(hdr);
2114 int mtyp = msg_type(hdr);
2115
2116 if (msg_user(hdr) != LINK_PROTOCOL)
2117 return true;
2118
2119 switch (mtyp) {
2120 case RESET_MSG:
2121 if (!l->in_session)
2122 return true;
2123 /* Accept only RESET with new session number */
2124 return more(session, curr_session);
2125 case ACTIVATE_MSG:
2126 if (!l->in_session)
2127 return true;
2128 /* Accept only ACTIVATE with new or current session number */
2129 return !less(session, curr_session);
2130 case STATE_MSG:
2131 /* Accept only STATE with current session number */
2132 if (!l->in_session)
2133 return false;
2134 if (session != curr_session)
2135 return false;
2136 /* Extra sanity check */
2137 if (!link_is_up(l) && msg_ack(hdr))
2138 return false;
2139 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2140 return true;
2141 /* Accept only STATE with new sequence number */
2142 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2143 default:
2144 return false;
2145 }
2146 }
2147
2148 /* tipc_link_proto_rcv(): receive link level protocol message :
2149 * Note that network plane id propagates through the network, and may
2150 * change at any time. The node with lowest numerical id determines
2151 * network plane
2152 */
tipc_link_proto_rcv(struct tipc_link * l,struct sk_buff * skb,struct sk_buff_head * xmitq)2153 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2154 struct sk_buff_head *xmitq)
2155 {
2156 struct tipc_msg *hdr = buf_msg(skb);
2157 struct tipc_gap_ack_blks *ga = NULL;
2158 bool reply = msg_probe(hdr), retransmitted = false;
2159 u32 dlen = msg_data_sz(hdr), glen = 0;
2160 u16 peers_snd_nxt = msg_next_sent(hdr);
2161 u16 peers_tol = msg_link_tolerance(hdr);
2162 u16 peers_prio = msg_linkprio(hdr);
2163 u16 gap = msg_seq_gap(hdr);
2164 u16 ack = msg_ack(hdr);
2165 u16 rcv_nxt = l->rcv_nxt;
2166 u16 rcvgap = 0;
2167 int mtyp = msg_type(hdr);
2168 int rc = 0, released;
2169 char *if_name;
2170 void *data;
2171
2172 trace_tipc_proto_rcv(skb, false, l->name);
2173
2174 if (dlen > U16_MAX)
2175 goto exit;
2176
2177 if (tipc_link_is_blocked(l) || !xmitq)
2178 goto exit;
2179
2180 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2181 l->net_plane = msg_net_plane(hdr);
2182
2183 skb_linearize(skb);
2184 hdr = buf_msg(skb);
2185 data = msg_data(hdr);
2186
2187 if (!tipc_link_validate_msg(l, hdr)) {
2188 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2189 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2190 goto exit;
2191 }
2192
2193 switch (mtyp) {
2194 case RESET_MSG:
2195 case ACTIVATE_MSG:
2196 /* Complete own link name with peer's interface name */
2197 if_name = strrchr(l->name, ':') + 1;
2198 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2199 break;
2200 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2201 break;
2202 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2203
2204 /* Update own tolerance if peer indicates a non-zero value */
2205 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2206 l->tolerance = peers_tol;
2207 l->bc_rcvlink->tolerance = peers_tol;
2208 }
2209 /* Update own priority if peer's priority is higher */
2210 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2211 l->priority = peers_prio;
2212
2213 /* If peer is going down we want full re-establish cycle */
2214 if (msg_peer_stopping(hdr)) {
2215 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2216 break;
2217 }
2218
2219 /* If this endpoint was re-created while peer was ESTABLISHING
2220 * it doesn't know current session number. Force re-synch.
2221 */
2222 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2223 l->session != msg_dest_session(hdr)) {
2224 if (less(l->session, msg_dest_session(hdr)))
2225 l->session = msg_dest_session(hdr) + 1;
2226 break;
2227 }
2228
2229 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2230 if (mtyp == RESET_MSG || !link_is_up(l))
2231 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2232
2233 /* ACTIVATE_MSG takes up link if it was already locally reset */
2234 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2235 rc = TIPC_LINK_UP_EVT;
2236
2237 l->peer_session = msg_session(hdr);
2238 l->in_session = true;
2239 l->peer_bearer_id = msg_bearer_id(hdr);
2240 if (l->mtu > msg_max_pkt(hdr))
2241 l->mtu = msg_max_pkt(hdr);
2242 break;
2243
2244 case STATE_MSG:
2245 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2246
2247 /* Update own tolerance if peer indicates a non-zero value */
2248 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2249 l->tolerance = peers_tol;
2250 l->bc_rcvlink->tolerance = peers_tol;
2251 }
2252 /* Update own prio if peer indicates a different value */
2253 if ((peers_prio != l->priority) &&
2254 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2255 l->priority = peers_prio;
2256 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2257 }
2258
2259 l->silent_intv_cnt = 0;
2260 l->stats.recv_states++;
2261 if (msg_probe(hdr))
2262 l->stats.recv_probes++;
2263
2264 if (!link_is_up(l)) {
2265 if (l->state == LINK_ESTABLISHING)
2266 rc = TIPC_LINK_UP_EVT;
2267 break;
2268 }
2269
2270 /* Receive Gap ACK blocks from peer if any */
2271 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2272 if(glen > dlen)
2273 break;
2274 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2275 &l->mon_state, l->bearer_id);
2276
2277 /* Send NACK if peer has sent pkts we haven't received yet */
2278 if ((reply || msg_is_keepalive(hdr)) &&
2279 more(peers_snd_nxt, rcv_nxt) &&
2280 !tipc_link_is_synching(l) &&
2281 skb_queue_empty(&l->deferdq))
2282 rcvgap = peers_snd_nxt - l->rcv_nxt;
2283 if (rcvgap || reply)
2284 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2285 rcvgap, 0, 0, xmitq);
2286
2287 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2288 &retransmitted, &rc);
2289 if (gap)
2290 l->stats.recv_nacks++;
2291 if (released || retransmitted)
2292 tipc_link_update_cwin(l, released, retransmitted);
2293 if (released)
2294 tipc_link_advance_backlog(l, xmitq);
2295 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2296 link_prepare_wakeup(l);
2297 }
2298 exit:
2299 kfree_skb(skb);
2300 return rc;
2301 }
2302
2303 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2304 */
tipc_link_build_bc_proto_msg(struct tipc_link * l,bool bcast,u16 peers_snd_nxt,struct sk_buff_head * xmitq)2305 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2306 u16 peers_snd_nxt,
2307 struct sk_buff_head *xmitq)
2308 {
2309 struct sk_buff *skb;
2310 struct tipc_msg *hdr;
2311 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2312 u16 ack = l->rcv_nxt - 1;
2313 u16 gap_to = peers_snd_nxt - 1;
2314
2315 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2316 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2317 if (!skb)
2318 return false;
2319 hdr = buf_msg(skb);
2320 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2321 msg_set_bcast_ack(hdr, ack);
2322 msg_set_bcgap_after(hdr, ack);
2323 if (dfrd_skb)
2324 gap_to = buf_seqno(dfrd_skb) - 1;
2325 msg_set_bcgap_to(hdr, gap_to);
2326 msg_set_non_seq(hdr, bcast);
2327 __skb_queue_tail(xmitq, skb);
2328 return true;
2329 }
2330
2331 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2332 *
2333 * Give a newly added peer node the sequence number where it should
2334 * start receiving and acking broadcast packets.
2335 */
tipc_link_build_bc_init_msg(struct tipc_link * l,struct sk_buff_head * xmitq)2336 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2337 struct sk_buff_head *xmitq)
2338 {
2339 struct sk_buff_head list;
2340
2341 __skb_queue_head_init(&list);
2342 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2343 return;
2344 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2345 tipc_link_xmit(l, &list, xmitq);
2346 }
2347
2348 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2349 */
tipc_link_bc_init_rcv(struct tipc_link * l,struct tipc_msg * hdr)2350 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2351 {
2352 int mtyp = msg_type(hdr);
2353 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2354
2355 if (link_is_up(l))
2356 return;
2357
2358 if (msg_user(hdr) == BCAST_PROTOCOL) {
2359 l->rcv_nxt = peers_snd_nxt;
2360 l->state = LINK_ESTABLISHED;
2361 return;
2362 }
2363
2364 if (l->peer_caps & TIPC_BCAST_SYNCH)
2365 return;
2366
2367 if (msg_peer_node_is_up(hdr))
2368 return;
2369
2370 /* Compatibility: accept older, less safe initial synch data */
2371 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2372 l->rcv_nxt = peers_snd_nxt;
2373 }
2374
2375 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2376 */
tipc_link_bc_sync_rcv(struct tipc_link * l,struct tipc_msg * hdr,struct sk_buff_head * xmitq)2377 int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2378 struct sk_buff_head *xmitq)
2379 {
2380 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2381 int rc = 0;
2382
2383 if (!link_is_up(l))
2384 return rc;
2385
2386 if (!msg_peer_node_is_up(hdr))
2387 return rc;
2388
2389 /* Open when peer ackowledges our bcast init msg (pkt #1) */
2390 if (msg_ack(hdr))
2391 l->bc_peer_is_up = true;
2392
2393 if (!l->bc_peer_is_up)
2394 return rc;
2395
2396 /* Ignore if peers_snd_nxt goes beyond receive window */
2397 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2398 return rc;
2399
2400 l->snd_nxt = peers_snd_nxt;
2401 if (link_bc_rcv_gap(l))
2402 rc |= TIPC_LINK_SND_STATE;
2403
2404 /* Return now if sender supports nack via STATE messages */
2405 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2406 return rc;
2407
2408 /* Otherwise, be backwards compatible */
2409
2410 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2411 l->nack_state = BC_NACK_SND_CONDITIONAL;
2412 return 0;
2413 }
2414
2415 /* Don't NACK if one was recently sent or peeked */
2416 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2417 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2418 return 0;
2419 }
2420
2421 /* Conditionally delay NACK sending until next synch rcv */
2422 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2423 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2424 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2425 return 0;
2426 }
2427
2428 /* Send NACK now but suppress next one */
2429 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2430 l->nack_state = BC_NACK_SND_SUPPRESS;
2431 return 0;
2432 }
2433
tipc_link_bc_ack_rcv(struct tipc_link * r,u16 acked,u16 gap,struct tipc_gap_ack_blks * ga,struct sk_buff_head * xmitq,struct sk_buff_head * retrq)2434 int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2435 struct tipc_gap_ack_blks *ga,
2436 struct sk_buff_head *xmitq,
2437 struct sk_buff_head *retrq)
2438 {
2439 struct tipc_link *l = r->bc_sndlink;
2440 bool unused = false;
2441 int rc = 0;
2442
2443 if (!link_is_up(r) || !r->bc_peer_is_up)
2444 return 0;
2445
2446 if (gap) {
2447 l->stats.recv_nacks++;
2448 r->stats.recv_nacks++;
2449 }
2450
2451 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2452 return 0;
2453
2454 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2455 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2456
2457 tipc_link_advance_backlog(l, xmitq);
2458 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2459 link_prepare_wakeup(l);
2460
2461 return rc;
2462 }
2463
2464 /* tipc_link_bc_nack_rcv(): receive broadcast nack message
2465 * This function is here for backwards compatibility, since
2466 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2467 */
tipc_link_bc_nack_rcv(struct tipc_link * l,struct sk_buff * skb,struct sk_buff_head * xmitq)2468 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2469 struct sk_buff_head *xmitq)
2470 {
2471 struct tipc_msg *hdr = buf_msg(skb);
2472 u32 dnode = msg_destnode(hdr);
2473 int mtyp = msg_type(hdr);
2474 u16 acked = msg_bcast_ack(hdr);
2475 u16 from = acked + 1;
2476 u16 to = msg_bcgap_to(hdr);
2477 u16 peers_snd_nxt = to + 1;
2478 int rc = 0;
2479
2480 kfree_skb(skb);
2481
2482 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2483 return 0;
2484
2485 if (mtyp != STATE_MSG)
2486 return 0;
2487
2488 if (dnode == tipc_own_addr(l->net)) {
2489 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2490 xmitq);
2491 l->stats.recv_nacks++;
2492 return rc;
2493 }
2494
2495 /* Msg for other node => suppress own NACK at next sync if applicable */
2496 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2497 l->nack_state = BC_NACK_SND_SUPPRESS;
2498
2499 return 0;
2500 }
2501
tipc_link_set_queue_limits(struct tipc_link * l,u32 min_win,u32 max_win)2502 void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2503 {
2504 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2505
2506 l->min_win = min_win;
2507 l->ssthresh = max_win;
2508 l->max_win = max_win;
2509 l->window = min_win;
2510 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2511 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2512 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2513 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2514 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2515 }
2516
2517 /**
2518 * link_reset_stats - reset link statistics
2519 * @l: pointer to link
2520 */
tipc_link_reset_stats(struct tipc_link * l)2521 void tipc_link_reset_stats(struct tipc_link *l)
2522 {
2523 memset(&l->stats, 0, sizeof(l->stats));
2524 }
2525
link_print(struct tipc_link * l,const char * str)2526 static void link_print(struct tipc_link *l, const char *str)
2527 {
2528 struct sk_buff *hskb = skb_peek(&l->transmq);
2529 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2530 u16 tail = l->snd_nxt - 1;
2531
2532 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2533 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2534 skb_queue_len(&l->transmq), head, tail,
2535 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2536 }
2537
2538 /* Parse and validate nested (link) properties valid for media, bearer and link
2539 */
tipc_nl_parse_link_prop(struct nlattr * prop,struct nlattr * props[])2540 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2541 {
2542 int err;
2543
2544 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2545 tipc_nl_prop_policy, NULL);
2546 if (err)
2547 return err;
2548
2549 if (props[TIPC_NLA_PROP_PRIO]) {
2550 u32 prio;
2551
2552 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2553 if (prio > TIPC_MAX_LINK_PRI)
2554 return -EINVAL;
2555 }
2556
2557 if (props[TIPC_NLA_PROP_TOL]) {
2558 u32 tol;
2559
2560 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2561 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2562 return -EINVAL;
2563 }
2564
2565 if (props[TIPC_NLA_PROP_WIN]) {
2566 u32 max_win;
2567
2568 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2569 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2570 return -EINVAL;
2571 }
2572
2573 return 0;
2574 }
2575
__tipc_nl_add_stats(struct sk_buff * skb,struct tipc_stats * s)2576 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2577 {
2578 int i;
2579 struct nlattr *stats;
2580
2581 struct nla_map {
2582 u32 key;
2583 u32 val;
2584 };
2585
2586 struct nla_map map[] = {
2587 {TIPC_NLA_STATS_RX_INFO, 0},
2588 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2589 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2590 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2591 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2592 {TIPC_NLA_STATS_TX_INFO, 0},
2593 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2594 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2595 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2596 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2597 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2598 s->msg_length_counts : 1},
2599 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2600 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2601 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2602 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2603 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2604 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2605 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2606 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2607 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2608 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2609 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2610 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2611 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2612 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2613 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2614 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2615 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2616 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2617 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2618 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2619 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2620 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2621 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2622 };
2623
2624 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2625 if (!stats)
2626 return -EMSGSIZE;
2627
2628 for (i = 0; i < ARRAY_SIZE(map); i++)
2629 if (nla_put_u32(skb, map[i].key, map[i].val))
2630 goto msg_full;
2631
2632 nla_nest_end(skb, stats);
2633
2634 return 0;
2635 msg_full:
2636 nla_nest_cancel(skb, stats);
2637
2638 return -EMSGSIZE;
2639 }
2640
2641 /* Caller should hold appropriate locks to protect the link */
__tipc_nl_add_link(struct net * net,struct tipc_nl_msg * msg,struct tipc_link * link,int nlflags)2642 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2643 struct tipc_link *link, int nlflags)
2644 {
2645 u32 self = tipc_own_addr(net);
2646 struct nlattr *attrs;
2647 struct nlattr *prop;
2648 void *hdr;
2649 int err;
2650
2651 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2652 nlflags, TIPC_NL_LINK_GET);
2653 if (!hdr)
2654 return -EMSGSIZE;
2655
2656 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2657 if (!attrs)
2658 goto msg_full;
2659
2660 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2661 goto attr_msg_full;
2662 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2663 goto attr_msg_full;
2664 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2665 goto attr_msg_full;
2666 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2667 goto attr_msg_full;
2668 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2669 goto attr_msg_full;
2670
2671 if (tipc_link_is_up(link))
2672 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2673 goto attr_msg_full;
2674 if (link->active)
2675 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2676 goto attr_msg_full;
2677
2678 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2679 if (!prop)
2680 goto attr_msg_full;
2681 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2682 goto prop_msg_full;
2683 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2684 goto prop_msg_full;
2685 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2686 link->window))
2687 goto prop_msg_full;
2688 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2689 goto prop_msg_full;
2690 nla_nest_end(msg->skb, prop);
2691
2692 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2693 if (err)
2694 goto attr_msg_full;
2695
2696 nla_nest_end(msg->skb, attrs);
2697 genlmsg_end(msg->skb, hdr);
2698
2699 return 0;
2700
2701 prop_msg_full:
2702 nla_nest_cancel(msg->skb, prop);
2703 attr_msg_full:
2704 nla_nest_cancel(msg->skb, attrs);
2705 msg_full:
2706 genlmsg_cancel(msg->skb, hdr);
2707
2708 return -EMSGSIZE;
2709 }
2710
__tipc_nl_add_bc_link_stat(struct sk_buff * skb,struct tipc_stats * stats)2711 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2712 struct tipc_stats *stats)
2713 {
2714 int i;
2715 struct nlattr *nest;
2716
2717 struct nla_map {
2718 __u32 key;
2719 __u32 val;
2720 };
2721
2722 struct nla_map map[] = {
2723 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2724 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2725 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2726 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2727 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2728 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2729 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2730 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2731 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2732 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2733 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2734 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2735 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2736 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2737 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2738 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2739 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2740 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2741 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2742 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2743 };
2744
2745 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2746 if (!nest)
2747 return -EMSGSIZE;
2748
2749 for (i = 0; i < ARRAY_SIZE(map); i++)
2750 if (nla_put_u32(skb, map[i].key, map[i].val))
2751 goto msg_full;
2752
2753 nla_nest_end(skb, nest);
2754
2755 return 0;
2756 msg_full:
2757 nla_nest_cancel(skb, nest);
2758
2759 return -EMSGSIZE;
2760 }
2761
tipc_nl_add_bc_link(struct net * net,struct tipc_nl_msg * msg,struct tipc_link * bcl)2762 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2763 struct tipc_link *bcl)
2764 {
2765 int err;
2766 void *hdr;
2767 struct nlattr *attrs;
2768 struct nlattr *prop;
2769 u32 bc_mode = tipc_bcast_get_mode(net);
2770 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2771
2772 if (!bcl)
2773 return 0;
2774
2775 tipc_bcast_lock(net);
2776
2777 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2778 NLM_F_MULTI, TIPC_NL_LINK_GET);
2779 if (!hdr) {
2780 tipc_bcast_unlock(net);
2781 return -EMSGSIZE;
2782 }
2783
2784 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2785 if (!attrs)
2786 goto msg_full;
2787
2788 /* The broadcast link is always up */
2789 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2790 goto attr_msg_full;
2791
2792 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2793 goto attr_msg_full;
2794 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2795 goto attr_msg_full;
2796 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2797 goto attr_msg_full;
2798 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2799 goto attr_msg_full;
2800
2801 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2802 if (!prop)
2803 goto attr_msg_full;
2804 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2805 goto prop_msg_full;
2806 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2807 goto prop_msg_full;
2808 if (bc_mode & BCLINK_MODE_SEL)
2809 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2810 bc_ratio))
2811 goto prop_msg_full;
2812 nla_nest_end(msg->skb, prop);
2813
2814 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2815 if (err)
2816 goto attr_msg_full;
2817
2818 tipc_bcast_unlock(net);
2819 nla_nest_end(msg->skb, attrs);
2820 genlmsg_end(msg->skb, hdr);
2821
2822 return 0;
2823
2824 prop_msg_full:
2825 nla_nest_cancel(msg->skb, prop);
2826 attr_msg_full:
2827 nla_nest_cancel(msg->skb, attrs);
2828 msg_full:
2829 tipc_bcast_unlock(net);
2830 genlmsg_cancel(msg->skb, hdr);
2831
2832 return -EMSGSIZE;
2833 }
2834
tipc_link_set_tolerance(struct tipc_link * l,u32 tol,struct sk_buff_head * xmitq)2835 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2836 struct sk_buff_head *xmitq)
2837 {
2838 l->tolerance = tol;
2839 if (l->bc_rcvlink)
2840 l->bc_rcvlink->tolerance = tol;
2841 if (link_is_up(l))
2842 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2843 }
2844
tipc_link_set_prio(struct tipc_link * l,u32 prio,struct sk_buff_head * xmitq)2845 void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2846 struct sk_buff_head *xmitq)
2847 {
2848 l->priority = prio;
2849 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2850 }
2851
tipc_link_set_abort_limit(struct tipc_link * l,u32 limit)2852 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2853 {
2854 l->abort_limit = limit;
2855 }
2856
2857 /**
2858 * tipc_link_dump - dump TIPC link data
2859 * @l: tipc link to be dumped
2860 * @dqueues: bitmask to decide if any link queue to be dumped?
2861 * - TIPC_DUMP_NONE: don't dump link queues
2862 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2863 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2864 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2865 * - TIPC_DUMP_INPUTQ: dump link input queue
2866 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2867 * - TIPC_DUMP_ALL: dump all the link queues above
2868 * @buf: returned buffer of dump data in format
2869 */
tipc_link_dump(struct tipc_link * l,u16 dqueues,char * buf)2870 int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2871 {
2872 int i = 0;
2873 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2874 struct sk_buff_head *list;
2875 struct sk_buff *hskb, *tskb;
2876 u32 len;
2877
2878 if (!l) {
2879 i += scnprintf(buf, sz, "link data: (null)\n");
2880 return i;
2881 }
2882
2883 i += scnprintf(buf, sz, "link data: %x", l->addr);
2884 i += scnprintf(buf + i, sz - i, " %x", l->state);
2885 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2886 i += scnprintf(buf + i, sz - i, " %u", l->session);
2887 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2888 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2889 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2890 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2891 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2892 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2893 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2894 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2895 i += scnprintf(buf + i, sz - i, " %u", 0);
2896 i += scnprintf(buf + i, sz - i, " %u", 0);
2897 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2898
2899 list = &l->transmq;
2900 len = skb_queue_len(list);
2901 hskb = skb_peek(list);
2902 tskb = skb_peek_tail(list);
2903 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2904 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2905 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2906
2907 list = &l->deferdq;
2908 len = skb_queue_len(list);
2909 hskb = skb_peek(list);
2910 tskb = skb_peek_tail(list);
2911 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2912 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2913 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2914
2915 list = &l->backlogq;
2916 len = skb_queue_len(list);
2917 hskb = skb_peek(list);
2918 tskb = skb_peek_tail(list);
2919 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2920 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2921 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2922
2923 list = l->inputq;
2924 len = skb_queue_len(list);
2925 hskb = skb_peek(list);
2926 tskb = skb_peek_tail(list);
2927 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2928 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2929 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2930
2931 if (dqueues & TIPC_DUMP_TRANSMQ) {
2932 i += scnprintf(buf + i, sz - i, "transmq: ");
2933 i += tipc_list_dump(&l->transmq, false, buf + i);
2934 }
2935 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2936 i += scnprintf(buf + i, sz - i,
2937 "backlogq: <%u %u %u %u %u>, ",
2938 l->backlog[TIPC_LOW_IMPORTANCE].len,
2939 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2940 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2941 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2942 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2943 i += tipc_list_dump(&l->backlogq, false, buf + i);
2944 }
2945 if (dqueues & TIPC_DUMP_DEFERDQ) {
2946 i += scnprintf(buf + i, sz - i, "deferdq: ");
2947 i += tipc_list_dump(&l->deferdq, false, buf + i);
2948 }
2949 if (dqueues & TIPC_DUMP_INPUTQ) {
2950 i += scnprintf(buf + i, sz - i, "inputq: ");
2951 i += tipc_list_dump(l->inputq, false, buf + i);
2952 }
2953 if (dqueues & TIPC_DUMP_WAKEUP) {
2954 i += scnprintf(buf + i, sz - i, "wakeup: ");
2955 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2956 }
2957
2958 return i;
2959 }
2960