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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
51struct 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 */
124struct 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 */
205static const char *link_co_err = "Link tunneling error, ";
206static const char *link_rst_msg = "Resetting link ";
207
208/* Send states for broadcast NACKs
209 */
210enum {
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/*
220 * Interval between NACKs when packets arrive out of order
221 */
222#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
223
224/* Link FSM states:
225 */
226enum {
227 LINK_ESTABLISHED = 0xe,
228 LINK_ESTABLISHING = 0xe << 4,
229 LINK_RESET = 0x1 << 8,
230 LINK_RESETTING = 0x2 << 12,
231 LINK_PEER_RESET = 0xd << 16,
232 LINK_FAILINGOVER = 0xf << 20,
233 LINK_SYNCHING = 0xc << 24
234};
235
236/* Link FSM state checking routines
237 */
238static int link_is_up(struct tipc_link *l)
239{
240 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
241}
242
243static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
244 struct sk_buff_head *xmitq);
245static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
246 bool probe_reply, u16 rcvgap,
247 int tolerance, int priority,
248 struct sk_buff_head *xmitq);
249static void link_print(struct tipc_link *l, const char *str);
250static int tipc_link_build_nack_msg(struct tipc_link *l,
251 struct sk_buff_head *xmitq);
252static void tipc_link_build_bc_init_msg(struct tipc_link *l,
253 struct sk_buff_head *xmitq);
254static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
255 struct tipc_link *l, u8 start_index);
256static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
257static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
258 u16 acked, u16 gap,
259 struct tipc_gap_ack_blks *ga,
260 struct sk_buff_head *xmitq,
261 bool *retransmitted, int *rc);
262static void tipc_link_update_cwin(struct tipc_link *l, int released,
263 bool retransmitted);
264/*
265 * Simple non-static link routines (i.e. referenced outside this file)
266 */
267bool tipc_link_is_up(struct tipc_link *l)
268{
269 return link_is_up(l);
270}
271
272bool tipc_link_peer_is_down(struct tipc_link *l)
273{
274 return l->state == LINK_PEER_RESET;
275}
276
277bool tipc_link_is_reset(struct tipc_link *l)
278{
279 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
280}
281
282bool tipc_link_is_establishing(struct tipc_link *l)
283{
284 return l->state == LINK_ESTABLISHING;
285}
286
287bool tipc_link_is_synching(struct tipc_link *l)
288{
289 return l->state == LINK_SYNCHING;
290}
291
292bool tipc_link_is_failingover(struct tipc_link *l)
293{
294 return l->state == LINK_FAILINGOVER;
295}
296
297bool tipc_link_is_blocked(struct tipc_link *l)
298{
299 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
300}
301
302static bool link_is_bc_sndlink(struct tipc_link *l)
303{
304 return !l->bc_sndlink;
305}
306
307static bool link_is_bc_rcvlink(struct tipc_link *l)
308{
309 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
310}
311
312void tipc_link_set_active(struct tipc_link *l, bool active)
313{
314 l->active = active;
315}
316
317u32 tipc_link_id(struct tipc_link *l)
318{
319 return l->peer_bearer_id << 16 | l->bearer_id;
320}
321
322int tipc_link_min_win(struct tipc_link *l)
323{
324 return l->min_win;
325}
326
327int tipc_link_max_win(struct tipc_link *l)
328{
329 return l->max_win;
330}
331
332int tipc_link_prio(struct tipc_link *l)
333{
334 return l->priority;
335}
336
337unsigned long tipc_link_tolerance(struct tipc_link *l)
338{
339 return l->tolerance;
340}
341
342struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
343{
344 return l->inputq;
345}
346
347char tipc_link_plane(struct tipc_link *l)
348{
349 return l->net_plane;
350}
351
352void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
353{
354 l->peer_caps = capabilities;
355}
356
357void tipc_link_add_bc_peer(struct tipc_link *snd_l,
358 struct tipc_link *uc_l,
359 struct sk_buff_head *xmitq)
360{
361 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
362
363 snd_l->ackers++;
364 rcv_l->acked = snd_l->snd_nxt - 1;
365 snd_l->state = LINK_ESTABLISHED;
366 tipc_link_build_bc_init_msg(uc_l, xmitq);
367}
368
369void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
370 struct tipc_link *rcv_l,
371 struct sk_buff_head *xmitq)
372{
373 u16 ack = snd_l->snd_nxt - 1;
374
375 snd_l->ackers--;
376 rcv_l->bc_peer_is_up = true;
377 rcv_l->state = LINK_ESTABLISHED;
378 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
379 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
380 tipc_link_reset(rcv_l);
381 rcv_l->state = LINK_RESET;
382 if (!snd_l->ackers) {
383 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
384 tipc_link_reset(snd_l);
385 snd_l->state = LINK_RESET;
386 __skb_queue_purge(xmitq);
387 }
388}
389
390int tipc_link_bc_peers(struct tipc_link *l)
391{
392 return l->ackers;
393}
394
395static u16 link_bc_rcv_gap(struct tipc_link *l)
396{
397 struct sk_buff *skb = skb_peek(&l->deferdq);
398 u16 gap = 0;
399
400 if (more(l->snd_nxt, l->rcv_nxt))
401 gap = l->snd_nxt - l->rcv_nxt;
402 if (skb)
403 gap = buf_seqno(skb) - l->rcv_nxt;
404 return gap;
405}
406
407void tipc_link_set_mtu(struct tipc_link *l, int mtu)
408{
409 l->mtu = mtu;
410}
411
412int tipc_link_mtu(struct tipc_link *l)
413{
414 return l->mtu;
415}
416
417int tipc_link_mss(struct tipc_link *l)
418{
419#ifdef CONFIG_TIPC_CRYPTO
420 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
421#else
422 return l->mtu - INT_H_SIZE;
423#endif
424}
425
426u16 tipc_link_rcv_nxt(struct tipc_link *l)
427{
428 return l->rcv_nxt;
429}
430
431u16 tipc_link_acked(struct tipc_link *l)
432{
433 return l->acked;
434}
435
436char *tipc_link_name(struct tipc_link *l)
437{
438 return l->name;
439}
440
441u32 tipc_link_state(struct tipc_link *l)
442{
443 return l->state;
444}
445
446/**
447 * tipc_link_create - create a new link
448 * @net: pointer to associated network namespace
449 * @if_name: associated interface name
450 * @bearer_id: id (index) of associated bearer
451 * @tolerance: link tolerance to be used by link
452 * @net_plane: network plane (A,B,c..) this link belongs to
453 * @mtu: mtu to be advertised by link
454 * @priority: priority to be used by link
455 * @min_win: minimal send window to be used by link
456 * @max_win: maximal send window to be used by link
457 * @session: session to be used by link
458 * @ownnode: identity of own node
459 * @peer: node id of peer node
460 * @peer_caps: bitmap describing peer node capabilities
461 * @bc_sndlink: the namespace global link used for broadcast sending
462 * @bc_rcvlink: the peer specific link used for broadcast reception
463 * @inputq: queue to put messages ready for delivery
464 * @namedq: queue to put binding table update messages ready for delivery
465 * @link: return value, pointer to put the created link
466 *
467 * Returns true if link was created, otherwise false
468 */
469bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
470 int tolerance, char net_plane, u32 mtu, int priority,
471 u32 min_win, u32 max_win, u32 session, u32 self,
472 u32 peer, u8 *peer_id, u16 peer_caps,
473 struct tipc_link *bc_sndlink,
474 struct tipc_link *bc_rcvlink,
475 struct sk_buff_head *inputq,
476 struct sk_buff_head *namedq,
477 struct tipc_link **link)
478{
479 char peer_str[NODE_ID_STR_LEN] = {0,};
480 char self_str[NODE_ID_STR_LEN] = {0,};
481 struct tipc_link *l;
482
483 l = kzalloc(sizeof(*l), GFP_ATOMIC);
484 if (!l)
485 return false;
486 *link = l;
487 l->session = session;
488
489 /* Set link name for unicast links only */
490 if (peer_id) {
491 tipc_nodeid2string(self_str, tipc_own_id(net));
492 if (strlen(self_str) > 16)
493 sprintf(self_str, "%x", self);
494 tipc_nodeid2string(peer_str, peer_id);
495 if (strlen(peer_str) > 16)
496 sprintf(peer_str, "%x", peer);
497 }
498 /* Peer i/f name will be completed by reset/activate message */
499 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
500 self_str, if_name, peer_str);
501
502 strcpy(l->if_name, if_name);
503 l->addr = peer;
504 l->peer_caps = peer_caps;
505 l->net = net;
506 l->in_session = false;
507 l->bearer_id = bearer_id;
508 l->tolerance = tolerance;
509 if (bc_rcvlink)
510 bc_rcvlink->tolerance = tolerance;
511 l->net_plane = net_plane;
512 l->advertised_mtu = mtu;
513 l->mtu = mtu;
514 l->priority = priority;
515 tipc_link_set_queue_limits(l, min_win, max_win);
516 l->ackers = 1;
517 l->bc_sndlink = bc_sndlink;
518 l->bc_rcvlink = bc_rcvlink;
519 l->inputq = inputq;
520 l->namedq = namedq;
521 l->state = LINK_RESETTING;
522 __skb_queue_head_init(&l->transmq);
523 __skb_queue_head_init(&l->backlogq);
524 __skb_queue_head_init(&l->deferdq);
525 __skb_queue_head_init(&l->failover_deferdq);
526 skb_queue_head_init(&l->wakeupq);
527 skb_queue_head_init(l->inputq);
528 return true;
529}
530
531/**
532 * tipc_link_bc_create - create new link to be used for broadcast
533 * @net: pointer to associated network namespace
534 * @mtu: mtu to be used initially if no peers
535 * @min_win: minimal send window to be used by link
536 * @max_win: maximal send window to be used by link
537 * @inputq: queue to put messages ready for delivery
538 * @namedq: queue to put binding table update messages ready for delivery
539 * @link: return value, pointer to put the created link
540 *
541 * Returns true if link was created, otherwise false
542 */
543bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
544 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
545 struct sk_buff_head *inputq,
546 struct sk_buff_head *namedq,
547 struct tipc_link *bc_sndlink,
548 struct tipc_link **link)
549{
550 struct tipc_link *l;
551
552 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
553 max_win, 0, ownnode, peer, NULL, peer_caps,
554 bc_sndlink, NULL, inputq, namedq, link))
555 return false;
556
557 l = *link;
558 if (peer_id) {
559 char peer_str[NODE_ID_STR_LEN] = {0,};
560
561 tipc_nodeid2string(peer_str, peer_id);
562 if (strlen(peer_str) > 16)
563 sprintf(peer_str, "%x", peer);
564 /* Broadcast receiver link name: "broadcast-link:<peer>" */
565 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
566 peer_str);
567 } else {
568 strcpy(l->name, tipc_bclink_name);
569 }
570 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
571 tipc_link_reset(l);
572 l->state = LINK_RESET;
573 l->ackers = 0;
574 l->bc_rcvlink = l;
575
576 /* Broadcast send link is always up */
577 if (link_is_bc_sndlink(l))
578 l->state = LINK_ESTABLISHED;
579
580 /* Disable replicast if even a single peer doesn't support it */
581 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
582 tipc_bcast_toggle_rcast(net, false);
583
584 return true;
585}
586
587/**
588 * tipc_link_fsm_evt - link finite state machine
589 * @l: pointer to link
590 * @evt: state machine event to be processed
591 */
592int tipc_link_fsm_evt(struct tipc_link *l, int evt)
593{
594 int rc = 0;
595 int old_state = l->state;
596
597 switch (l->state) {
598 case LINK_RESETTING:
599 switch (evt) {
600 case LINK_PEER_RESET_EVT:
601 l->state = LINK_PEER_RESET;
602 break;
603 case LINK_RESET_EVT:
604 l->state = LINK_RESET;
605 break;
606 case LINK_FAILURE_EVT:
607 case LINK_FAILOVER_BEGIN_EVT:
608 case LINK_ESTABLISH_EVT:
609 case LINK_FAILOVER_END_EVT:
610 case LINK_SYNCH_BEGIN_EVT:
611 case LINK_SYNCH_END_EVT:
612 default:
613 goto illegal_evt;
614 }
615 break;
616 case LINK_RESET:
617 switch (evt) {
618 case LINK_PEER_RESET_EVT:
619 l->state = LINK_ESTABLISHING;
620 break;
621 case LINK_FAILOVER_BEGIN_EVT:
622 l->state = LINK_FAILINGOVER;
623 case LINK_FAILURE_EVT:
624 case LINK_RESET_EVT:
625 case LINK_ESTABLISH_EVT:
626 case LINK_FAILOVER_END_EVT:
627 break;
628 case LINK_SYNCH_BEGIN_EVT:
629 case LINK_SYNCH_END_EVT:
630 default:
631 goto illegal_evt;
632 }
633 break;
634 case LINK_PEER_RESET:
635 switch (evt) {
636 case LINK_RESET_EVT:
637 l->state = LINK_ESTABLISHING;
638 break;
639 case LINK_PEER_RESET_EVT:
640 case LINK_ESTABLISH_EVT:
641 case LINK_FAILURE_EVT:
642 break;
643 case LINK_SYNCH_BEGIN_EVT:
644 case LINK_SYNCH_END_EVT:
645 case LINK_FAILOVER_BEGIN_EVT:
646 case LINK_FAILOVER_END_EVT:
647 default:
648 goto illegal_evt;
649 }
650 break;
651 case LINK_FAILINGOVER:
652 switch (evt) {
653 case LINK_FAILOVER_END_EVT:
654 l->state = LINK_RESET;
655 break;
656 case LINK_PEER_RESET_EVT:
657 case LINK_RESET_EVT:
658 case LINK_ESTABLISH_EVT:
659 case LINK_FAILURE_EVT:
660 break;
661 case LINK_FAILOVER_BEGIN_EVT:
662 case LINK_SYNCH_BEGIN_EVT:
663 case LINK_SYNCH_END_EVT:
664 default:
665 goto illegal_evt;
666 }
667 break;
668 case LINK_ESTABLISHING:
669 switch (evt) {
670 case LINK_ESTABLISH_EVT:
671 l->state = LINK_ESTABLISHED;
672 break;
673 case LINK_FAILOVER_BEGIN_EVT:
674 l->state = LINK_FAILINGOVER;
675 break;
676 case LINK_RESET_EVT:
677 l->state = LINK_RESET;
678 break;
679 case LINK_FAILURE_EVT:
680 case LINK_PEER_RESET_EVT:
681 case LINK_SYNCH_BEGIN_EVT:
682 case LINK_FAILOVER_END_EVT:
683 break;
684 case LINK_SYNCH_END_EVT:
685 default:
686 goto illegal_evt;
687 }
688 break;
689 case LINK_ESTABLISHED:
690 switch (evt) {
691 case LINK_PEER_RESET_EVT:
692 l->state = LINK_PEER_RESET;
693 rc |= TIPC_LINK_DOWN_EVT;
694 break;
695 case LINK_FAILURE_EVT:
696 l->state = LINK_RESETTING;
697 rc |= TIPC_LINK_DOWN_EVT;
698 break;
699 case LINK_RESET_EVT:
700 l->state = LINK_RESET;
701 break;
702 case LINK_ESTABLISH_EVT:
703 case LINK_SYNCH_END_EVT:
704 break;
705 case LINK_SYNCH_BEGIN_EVT:
706 l->state = LINK_SYNCHING;
707 break;
708 case LINK_FAILOVER_BEGIN_EVT:
709 case LINK_FAILOVER_END_EVT:
710 default:
711 goto illegal_evt;
712 }
713 break;
714 case LINK_SYNCHING:
715 switch (evt) {
716 case LINK_PEER_RESET_EVT:
717 l->state = LINK_PEER_RESET;
718 rc |= TIPC_LINK_DOWN_EVT;
719 break;
720 case LINK_FAILURE_EVT:
721 l->state = LINK_RESETTING;
722 rc |= TIPC_LINK_DOWN_EVT;
723 break;
724 case LINK_RESET_EVT:
725 l->state = LINK_RESET;
726 break;
727 case LINK_ESTABLISH_EVT:
728 case LINK_SYNCH_BEGIN_EVT:
729 break;
730 case LINK_SYNCH_END_EVT:
731 l->state = LINK_ESTABLISHED;
732 break;
733 case LINK_FAILOVER_BEGIN_EVT:
734 case LINK_FAILOVER_END_EVT:
735 default:
736 goto illegal_evt;
737 }
738 break;
739 default:
740 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
741 }
742 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
743 return rc;
744illegal_evt:
745 pr_err("Illegal FSM event %x in state %x on link %s\n",
746 evt, l->state, l->name);
747 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
748 return rc;
749}
750
751/* link_profile_stats - update statistical profiling of traffic
752 */
753static void link_profile_stats(struct tipc_link *l)
754{
755 struct sk_buff *skb;
756 struct tipc_msg *msg;
757 int length;
758
759 /* Update counters used in statistical profiling of send traffic */
760 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
761 l->stats.queue_sz_counts++;
762
763 skb = skb_peek(&l->transmq);
764 if (!skb)
765 return;
766 msg = buf_msg(skb);
767 length = msg_size(msg);
768
769 if (msg_user(msg) == MSG_FRAGMENTER) {
770 if (msg_type(msg) != FIRST_FRAGMENT)
771 return;
772 length = msg_size(msg_inner_hdr(msg));
773 }
774 l->stats.msg_lengths_total += length;
775 l->stats.msg_length_counts++;
776 if (length <= 64)
777 l->stats.msg_length_profile[0]++;
778 else if (length <= 256)
779 l->stats.msg_length_profile[1]++;
780 else if (length <= 1024)
781 l->stats.msg_length_profile[2]++;
782 else if (length <= 4096)
783 l->stats.msg_length_profile[3]++;
784 else if (length <= 16384)
785 l->stats.msg_length_profile[4]++;
786 else if (length <= 32768)
787 l->stats.msg_length_profile[5]++;
788 else
789 l->stats.msg_length_profile[6]++;
790}
791
792/**
793 * tipc_link_too_silent - check if link is "too silent"
794 * @l: tipc link to be checked
795 *
796 * Returns true if the link 'silent_intv_cnt' is about to reach the
797 * 'abort_limit' value, otherwise false
798 */
799bool tipc_link_too_silent(struct tipc_link *l)
800{
801 return (l->silent_intv_cnt + 2 > l->abort_limit);
802}
803
804/* tipc_link_timeout - perform periodic task as instructed from node timeout
805 */
806int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
807{
808 int mtyp = 0;
809 int rc = 0;
810 bool state = false;
811 bool probe = false;
812 bool setup = false;
813 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
814 u16 bc_acked = l->bc_rcvlink->acked;
815 struct tipc_mon_state *mstate = &l->mon_state;
816
817 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
818 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
819 switch (l->state) {
820 case LINK_ESTABLISHED:
821 case LINK_SYNCHING:
822 mtyp = STATE_MSG;
823 link_profile_stats(l);
824 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
825 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
826 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
827 state = bc_acked != bc_snt;
828 state |= l->bc_rcvlink->rcv_unacked;
829 state |= l->rcv_unacked;
830 state |= !skb_queue_empty(&l->transmq);
831 probe = mstate->probing;
832 probe |= l->silent_intv_cnt;
833 if (probe || mstate->monitoring)
834 l->silent_intv_cnt++;
835 probe |= !skb_queue_empty(&l->deferdq);
836 if (l->snd_nxt == l->checkpoint) {
837 tipc_link_update_cwin(l, 0, 0);
838 probe = true;
839 }
840 l->checkpoint = l->snd_nxt;
841 break;
842 case LINK_RESET:
843 setup = l->rst_cnt++ <= 4;
844 setup |= !(l->rst_cnt % 16);
845 mtyp = RESET_MSG;
846 break;
847 case LINK_ESTABLISHING:
848 setup = true;
849 mtyp = ACTIVATE_MSG;
850 break;
851 case LINK_PEER_RESET:
852 case LINK_RESETTING:
853 case LINK_FAILINGOVER:
854 break;
855 default:
856 break;
857 }
858
859 if (state || probe || setup)
860 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
861
862 return rc;
863}
864
865/**
866 * link_schedule_user - schedule a message sender for wakeup after congestion
867 * @l: congested link
868 * @hdr: header of message that is being sent
869 * Create pseudo msg to send back to user when congestion abates
870 */
871static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
872{
873 u32 dnode = tipc_own_addr(l->net);
874 u32 dport = msg_origport(hdr);
875 struct sk_buff *skb;
876
877 /* Create and schedule wakeup pseudo message */
878 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
879 dnode, l->addr, dport, 0, 0);
880 if (!skb)
881 return -ENOBUFS;
882 msg_set_dest_droppable(buf_msg(skb), true);
883 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
884 skb_queue_tail(&l->wakeupq, skb);
885 l->stats.link_congs++;
886 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
887 return -ELINKCONG;
888}
889
890/**
891 * link_prepare_wakeup - prepare users for wakeup after congestion
892 * @l: congested link
893 * Wake up a number of waiting users, as permitted by available space
894 * in the send queue
895 */
896static void link_prepare_wakeup(struct tipc_link *l)
897{
898 struct sk_buff_head *wakeupq = &l->wakeupq;
899 struct sk_buff_head *inputq = l->inputq;
900 struct sk_buff *skb, *tmp;
901 struct sk_buff_head tmpq;
902 int avail[5] = {0,};
903 int imp = 0;
904
905 __skb_queue_head_init(&tmpq);
906
907 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
908 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
909
910 skb_queue_walk_safe(wakeupq, skb, tmp) {
911 imp = TIPC_SKB_CB(skb)->chain_imp;
912 if (avail[imp] <= 0)
913 continue;
914 avail[imp]--;
915 __skb_unlink(skb, wakeupq);
916 __skb_queue_tail(&tmpq, skb);
917 }
918
919 spin_lock_bh(&inputq->lock);
920 skb_queue_splice_tail(&tmpq, inputq);
921 spin_unlock_bh(&inputq->lock);
922
923}
924
925/**
926 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
927 * the given skb should be next attempted
928 * @skb: skb to set a future retransmission time for
929 * @l: link the skb will be transmitted on
930 */
931static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
932 struct tipc_link *l)
933{
934 if (link_is_bc_sndlink(l))
935 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
936 else
937 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
938}
939
940void tipc_link_reset(struct tipc_link *l)
941{
942 struct sk_buff_head list;
943 u32 imp;
944
945 __skb_queue_head_init(&list);
946
947 l->in_session = false;
948 /* Force re-synch of peer session number before establishing */
949 l->peer_session--;
950 l->session++;
951 l->mtu = l->advertised_mtu;
952
953 spin_lock_bh(&l->wakeupq.lock);
954 skb_queue_splice_init(&l->wakeupq, &list);
955 spin_unlock_bh(&l->wakeupq.lock);
956
957 spin_lock_bh(&l->inputq->lock);
958 skb_queue_splice_init(&list, l->inputq);
959 spin_unlock_bh(&l->inputq->lock);
960
961 __skb_queue_purge(&l->transmq);
962 __skb_queue_purge(&l->deferdq);
963 __skb_queue_purge(&l->backlogq);
964 __skb_queue_purge(&l->failover_deferdq);
965 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
966 l->backlog[imp].len = 0;
967 l->backlog[imp].target_bskb = NULL;
968 }
969 kfree_skb(l->reasm_buf);
970 kfree_skb(l->reasm_tnlmsg);
971 kfree_skb(l->failover_reasm_skb);
972 l->reasm_buf = NULL;
973 l->reasm_tnlmsg = NULL;
974 l->failover_reasm_skb = NULL;
975 l->rcv_unacked = 0;
976 l->snd_nxt = 1;
977 l->rcv_nxt = 1;
978 l->snd_nxt_state = 1;
979 l->rcv_nxt_state = 1;
980 l->acked = 0;
981 l->last_gap = 0;
982 kfree(l->last_ga);
983 l->last_ga = NULL;
984 l->silent_intv_cnt = 0;
985 l->rst_cnt = 0;
986 l->bc_peer_is_up = false;
987 memset(&l->mon_state, 0, sizeof(l->mon_state));
988 tipc_link_reset_stats(l);
989}
990
991/**
992 * tipc_link_xmit(): enqueue buffer list according to queue situation
993 * @l: link to use
994 * @list: chain of buffers containing message
995 * @xmitq: returned list of packets to be sent by caller
996 *
997 * Consumes the buffer chain.
998 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
999 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1000 */
1001int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1002 struct sk_buff_head *xmitq)
1003{
1004 struct tipc_msg *hdr = buf_msg(skb_peek(list));
1005 struct sk_buff_head *backlogq = &l->backlogq;
1006 struct sk_buff_head *transmq = &l->transmq;
1007 struct sk_buff *skb, *_skb;
1008 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1009 u16 ack = l->rcv_nxt - 1;
1010 u16 seqno = l->snd_nxt;
1011 int pkt_cnt = skb_queue_len(list);
1012 int imp = msg_importance(hdr);
1013 unsigned int mss = tipc_link_mss(l);
1014 unsigned int cwin = l->window;
1015 unsigned int mtu = l->mtu;
1016 bool new_bundle;
1017 int rc = 0;
1018
1019 if (unlikely(msg_size(hdr) > mtu)) {
1020 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1021 skb_queue_len(list), msg_user(hdr),
1022 msg_type(hdr), msg_size(hdr), mtu);
1023 __skb_queue_purge(list);
1024 return -EMSGSIZE;
1025 }
1026
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
1088static 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
1130static 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 */
1179static 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 */
1228static 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 default:
1260 pr_warn("Dropping received illegal msg type\n");
1261 kfree_skb(skb);
1262 return true;
1263 };
1264}
1265
1266/* tipc_link_input - process packet that has passed link protocol check
1267 *
1268 * Consumes buffer
1269 */
1270static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1271 struct sk_buff_head *inputq,
1272 struct sk_buff **reasm_skb)
1273{
1274 struct tipc_msg *hdr = buf_msg(skb);
1275 struct sk_buff *iskb;
1276 struct sk_buff_head tmpq;
1277 int usr = msg_user(hdr);
1278 int pos = 0;
1279
1280 if (usr == MSG_BUNDLER) {
1281 skb_queue_head_init(&tmpq);
1282 l->stats.recv_bundles++;
1283 l->stats.recv_bundled += msg_msgcnt(hdr);
1284 while (tipc_msg_extract(skb, &iskb, &pos))
1285 tipc_data_input(l, iskb, &tmpq);
1286 tipc_skb_queue_splice_tail(&tmpq, inputq);
1287 return 0;
1288 } else if (usr == MSG_FRAGMENTER) {
1289 l->stats.recv_fragments++;
1290 if (tipc_buf_append(reasm_skb, &skb)) {
1291 l->stats.recv_fragmented++;
1292 tipc_data_input(l, skb, inputq);
1293 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1294 pr_warn_ratelimited("Unable to build fragment list\n");
1295 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1296 }
1297 return 0;
1298 } else if (usr == BCAST_PROTOCOL) {
1299 tipc_bcast_lock(l->net);
1300 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1301 tipc_bcast_unlock(l->net);
1302 }
1303
1304 kfree_skb(skb);
1305 return 0;
1306}
1307
1308/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1309 * inner message along with the ones in the old link's
1310 * deferdq
1311 * @l: tunnel link
1312 * @skb: TUNNEL_PROTOCOL message
1313 * @inputq: queue to put messages ready for delivery
1314 */
1315static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1316 struct sk_buff_head *inputq)
1317{
1318 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1319 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1320 struct sk_buff_head *fdefq = &l->failover_deferdq;
1321 struct tipc_msg *hdr = buf_msg(skb);
1322 struct sk_buff *iskb;
1323 int ipos = 0;
1324 int rc = 0;
1325 u16 seqno;
1326
1327 if (msg_type(hdr) == SYNCH_MSG) {
1328 kfree_skb(skb);
1329 return 0;
1330 }
1331
1332 /* Not a fragment? */
1333 if (likely(!msg_nof_fragms(hdr))) {
1334 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1335 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1336 skb_queue_len(fdefq));
1337 return 0;
1338 }
1339 kfree_skb(skb);
1340 } else {
1341 /* Set fragment type for buf_append */
1342 if (msg_fragm_no(hdr) == 1)
1343 msg_set_type(hdr, FIRST_FRAGMENT);
1344 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1345 msg_set_type(hdr, FRAGMENT);
1346 else
1347 msg_set_type(hdr, LAST_FRAGMENT);
1348
1349 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1350 /* Successful but non-complete reassembly? */
1351 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1352 return 0;
1353 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1354 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1355 }
1356 iskb = skb;
1357 }
1358
1359 do {
1360 seqno = buf_seqno(iskb);
1361 if (unlikely(less(seqno, l->drop_point))) {
1362 kfree_skb(iskb);
1363 continue;
1364 }
1365 if (unlikely(seqno != l->drop_point)) {
1366 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1367 continue;
1368 }
1369
1370 l->drop_point++;
1371 if (!tipc_data_input(l, iskb, inputq))
1372 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1373 if (unlikely(rc))
1374 break;
1375 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1376
1377 return rc;
1378}
1379
1380/**
1381 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1382 * @ga: returned pointer to the Gap ACK blocks if any
1383 * @l: the tipc link
1384 * @hdr: the PROTOCOL/STATE_MSG header
1385 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1386 *
1387 * Return: the total Gap ACK blocks size
1388 */
1389u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1390 struct tipc_msg *hdr, bool uc)
1391{
1392 struct tipc_gap_ack_blks *p;
1393 u16 sz = 0;
1394
1395 /* Does peer support the Gap ACK blocks feature? */
1396 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1397 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1398 sz = ntohs(p->len);
1399 /* Sanity check */
1400 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1401 /* Good, check if the desired type exists */
1402 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1403 goto ok;
1404 /* Backward compatible: peer might not support bc, but uc? */
1405 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1406 if (p->ugack_cnt) {
1407 p->bgack_cnt = 0;
1408 goto ok;
1409 }
1410 }
1411 }
1412 /* Other cases: ignore! */
1413 p = NULL;
1414
1415ok:
1416 *ga = p;
1417 return sz;
1418}
1419
1420static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1421 struct tipc_link *l, u8 start_index)
1422{
1423 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1424 struct sk_buff *skb = skb_peek(&l->deferdq);
1425 u16 expect, seqno = 0;
1426 u8 n = 0;
1427
1428 if (!skb)
1429 return 0;
1430
1431 expect = buf_seqno(skb);
1432 skb_queue_walk(&l->deferdq, skb) {
1433 seqno = buf_seqno(skb);
1434 if (unlikely(more(seqno, expect))) {
1435 gacks[n].ack = htons(expect - 1);
1436 gacks[n].gap = htons(seqno - expect);
1437 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1438 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1439 l->name, n,
1440 skb_queue_len(&l->deferdq));
1441 return n;
1442 }
1443 } else if (unlikely(less(seqno, expect))) {
1444 pr_warn("Unexpected skb in deferdq!\n");
1445 continue;
1446 }
1447 expect = seqno + 1;
1448 }
1449
1450 /* last block */
1451 gacks[n].ack = htons(seqno);
1452 gacks[n].gap = 0;
1453 n++;
1454 return n;
1455}
1456
1457/* tipc_build_gap_ack_blks - build Gap ACK blocks
1458 * @l: tipc unicast link
1459 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1460 *
1461 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1462 * links of a certain peer, the buffer after built has the network data format
1463 * as found at the struct tipc_gap_ack_blks definition.
1464 *
1465 * returns the actual allocated memory size
1466 */
1467static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1468{
1469 struct tipc_link *bcl = l->bc_rcvlink;
1470 struct tipc_gap_ack_blks *ga;
1471 u16 len;
1472
1473 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1474
1475 /* Start with broadcast link first */
1476 tipc_bcast_lock(bcl->net);
1477 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1478 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1479 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1480 tipc_bcast_unlock(bcl->net);
1481
1482 /* Now for unicast link, but an explicit NACK only (???) */
1483 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1484 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1485
1486 /* Total len */
1487 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1488 ga->len = htons(len);
1489 return len;
1490}
1491
1492/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1493 * acked packets, also doing retransmissions if
1494 * gaps found
1495 * @l: tipc link with transmq queue to be advanced
1496 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1497 * @acked: seqno of last packet acked by peer without any gaps before
1498 * @gap: # of gap packets
1499 * @ga: buffer pointer to Gap ACK blocks from peer
1500 * @xmitq: queue for accumulating the retransmitted packets if any
1501 * @retransmitted: returned boolean value if a retransmission is really issued
1502 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1503 * happens (- unlikely case)
1504 *
1505 * Return: the number of packets released from the link transmq
1506 */
1507static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1508 u16 acked, u16 gap,
1509 struct tipc_gap_ack_blks *ga,
1510 struct sk_buff_head *xmitq,
1511 bool *retransmitted, int *rc)
1512{
1513 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1514 struct tipc_gap_ack *gacks = NULL;
1515 struct sk_buff *skb, *_skb, *tmp;
1516 struct tipc_msg *hdr;
1517 u32 qlen = skb_queue_len(&l->transmq);
1518 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1519 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1520 u16 ack = l->rcv_nxt - 1;
1521 u16 seqno, n = 0;
1522 u16 end = r->acked, start = end, offset = r->last_gap;
1523 u16 si = (last_ga) ? last_ga->start_index : 0;
1524 bool is_uc = !link_is_bc_sndlink(l);
1525 bool bc_has_acked = false;
1526
1527 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1528
1529 /* Determine Gap ACK blocks if any for the particular link */
1530 if (ga && is_uc) {
1531 /* Get the Gap ACKs, uc part */
1532 gack_cnt = ga->ugack_cnt;
1533 gacks = &ga->gacks[ga->bgack_cnt];
1534 } else if (ga) {
1535 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1536 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1537 GFP_ATOMIC);
1538 if (likely(this_ga)) {
1539 this_ga->start_index = 0;
1540 /* Start with the bc Gap ACKs */
1541 gack_cnt = this_ga->bgack_cnt;
1542 gacks = &this_ga->gacks[0];
1543 } else {
1544 /* Hmm, we can get in trouble..., simply ignore it */
1545 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1546 }
1547 }
1548
1549 /* Advance the link transmq */
1550 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1551 seqno = buf_seqno(skb);
1552
1553next_gap_ack:
1554 if (less_eq(seqno, nacked)) {
1555 if (is_uc)
1556 goto release;
1557 /* Skip packets peer has already acked */
1558 if (!more(seqno, r->acked))
1559 continue;
1560 /* Get the next of last Gap ACK blocks */
1561 while (more(seqno, end)) {
1562 if (!last_ga || si >= last_ga->bgack_cnt)
1563 break;
1564 start = end + offset + 1;
1565 end = ntohs(last_ga->gacks[si].ack);
1566 offset = ntohs(last_ga->gacks[si].gap);
1567 si++;
1568 WARN_ONCE(more(start, end) ||
1569 (!offset &&
1570 si < last_ga->bgack_cnt) ||
1571 si > MAX_GAP_ACK_BLKS,
1572 "Corrupted Gap ACK: %d %d %d %d %d\n",
1573 start, end, offset, si,
1574 last_ga->bgack_cnt);
1575 }
1576 /* Check against the last Gap ACK block */
1577 if (in_range(seqno, start, end))
1578 continue;
1579 /* Update/release the packet peer is acking */
1580 bc_has_acked = true;
1581 if (--TIPC_SKB_CB(skb)->ackers)
1582 continue;
1583release:
1584 /* release skb */
1585 __skb_unlink(skb, &l->transmq);
1586 kfree_skb(skb);
1587 } else if (less_eq(seqno, nacked + ngap)) {
1588 /* First gap: check if repeated retrans failures? */
1589 if (unlikely(seqno == acked + 1 &&
1590 link_retransmit_failure(l, r, rc))) {
1591 /* Ignore this bc Gap ACKs if any */
1592 kfree(this_ga);
1593 this_ga = NULL;
1594 break;
1595 }
1596 /* retransmit skb if unrestricted*/
1597 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1598 continue;
1599 tipc_link_set_skb_retransmit_time(skb, l);
1600 _skb = pskb_copy(skb, GFP_ATOMIC);
1601 if (!_skb)
1602 continue;
1603 hdr = buf_msg(_skb);
1604 msg_set_ack(hdr, ack);
1605 msg_set_bcast_ack(hdr, bc_ack);
1606 _skb->priority = TC_PRIO_CONTROL;
1607 __skb_queue_tail(xmitq, _skb);
1608 l->stats.retransmitted++;
1609 if (!is_uc)
1610 r->stats.retransmitted++;
1611 *retransmitted = true;
1612 /* Increase actual retrans counter & mark first time */
1613 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1614 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1615 } else {
1616 /* retry with Gap ACK blocks if any */
1617 if (n >= gack_cnt)
1618 break;
1619 nacked = ntohs(gacks[n].ack);
1620 ngap = ntohs(gacks[n].gap);
1621 n++;
1622 goto next_gap_ack;
1623 }
1624 }
1625
1626 /* Renew last Gap ACK blocks for bc if needed */
1627 if (bc_has_acked) {
1628 if (this_ga) {
1629 kfree(last_ga);
1630 r->last_ga = this_ga;
1631 r->last_gap = gap;
1632 } else if (last_ga) {
1633 if (less(acked, start)) {
1634 si--;
1635 offset = start - acked - 1;
1636 } else if (less(acked, end)) {
1637 acked = end;
1638 }
1639 if (si < last_ga->bgack_cnt) {
1640 last_ga->start_index = si;
1641 r->last_gap = offset;
1642 } else {
1643 kfree(last_ga);
1644 r->last_ga = NULL;
1645 r->last_gap = 0;
1646 }
1647 } else {
1648 r->last_gap = 0;
1649 }
1650 r->acked = acked;
1651 } else {
1652 kfree(this_ga);
1653 }
1654
1655 return qlen - skb_queue_len(&l->transmq);
1656}
1657
1658/* tipc_link_build_state_msg: prepare link state message for transmission
1659 *
1660 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1661 * risk of ack storms towards the sender
1662 */
1663int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1664{
1665 if (!l)
1666 return 0;
1667
1668 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1669 if (link_is_bc_rcvlink(l)) {
1670 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1671 return 0;
1672 l->rcv_unacked = 0;
1673
1674 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1675 l->snd_nxt = l->rcv_nxt;
1676 return TIPC_LINK_SND_STATE;
1677 }
1678 /* Unicast ACK */
1679 l->rcv_unacked = 0;
1680 l->stats.sent_acks++;
1681 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1682 return 0;
1683}
1684
1685/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1686 */
1687void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1688{
1689 int mtyp = RESET_MSG;
1690 struct sk_buff *skb;
1691
1692 if (l->state == LINK_ESTABLISHING)
1693 mtyp = ACTIVATE_MSG;
1694
1695 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1696
1697 /* Inform peer that this endpoint is going down if applicable */
1698 skb = skb_peek_tail(xmitq);
1699 if (skb && (l->state == LINK_RESET))
1700 msg_set_peer_stopping(buf_msg(skb), 1);
1701}
1702
1703/* tipc_link_build_nack_msg: prepare link nack message for transmission
1704 * Note that sending of broadcast NACK is coordinated among nodes, to
1705 * reduce the risk of NACK storms towards the sender
1706 */
1707static int tipc_link_build_nack_msg(struct tipc_link *l,
1708 struct sk_buff_head *xmitq)
1709{
1710 u32 def_cnt = ++l->stats.deferred_recv;
1711 struct sk_buff_head *dfq = &l->deferdq;
1712 u32 defq_len = skb_queue_len(dfq);
1713 int match1, match2;
1714
1715 if (link_is_bc_rcvlink(l)) {
1716 match1 = def_cnt & 0xf;
1717 match2 = tipc_own_addr(l->net) & 0xf;
1718 if (match1 == match2)
1719 return TIPC_LINK_SND_STATE;
1720 return 0;
1721 }
1722
1723 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1724 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1725
1726 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1727 rcvgap, 0, 0, xmitq);
1728 }
1729 return 0;
1730}
1731
1732/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1733 * @l: the link that should handle the message
1734 * @skb: TIPC packet
1735 * @xmitq: queue to place packets to be sent after this call
1736 */
1737int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1738 struct sk_buff_head *xmitq)
1739{
1740 struct sk_buff_head *defq = &l->deferdq;
1741 struct tipc_msg *hdr = buf_msg(skb);
1742 u16 seqno, rcv_nxt, win_lim;
1743 int released = 0;
1744 int rc = 0;
1745
1746 /* Verify and update link state */
1747 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1748 return tipc_link_proto_rcv(l, skb, xmitq);
1749
1750 /* Don't send probe at next timeout expiration */
1751 l->silent_intv_cnt = 0;
1752
1753 do {
1754 hdr = buf_msg(skb);
1755 seqno = msg_seqno(hdr);
1756 rcv_nxt = l->rcv_nxt;
1757 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1758
1759 if (unlikely(!link_is_up(l))) {
1760 if (l->state == LINK_ESTABLISHING)
1761 rc = TIPC_LINK_UP_EVT;
1762 kfree_skb(skb);
1763 break;
1764 }
1765
1766 /* Drop if outside receive window */
1767 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1768 l->stats.duplicates++;
1769 kfree_skb(skb);
1770 break;
1771 }
1772 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1773 NULL, NULL, NULL, NULL);
1774
1775 /* Defer delivery if sequence gap */
1776 if (unlikely(seqno != rcv_nxt)) {
1777 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1778 l->stats.duplicates++;
1779 rc |= tipc_link_build_nack_msg(l, xmitq);
1780 break;
1781 }
1782
1783 /* Deliver packet */
1784 l->rcv_nxt++;
1785 l->stats.recv_pkts++;
1786
1787 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1788 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1789 else if (!tipc_data_input(l, skb, l->inputq))
1790 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1791 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1792 rc |= tipc_link_build_state_msg(l, xmitq);
1793 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1794 break;
1795 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1796
1797 /* Forward queues and wake up waiting users */
1798 if (released) {
1799 tipc_link_update_cwin(l, released, 0);
1800 tipc_link_advance_backlog(l, xmitq);
1801 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1802 link_prepare_wakeup(l);
1803 }
1804 return rc;
1805}
1806
1807static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1808 bool probe_reply, u16 rcvgap,
1809 int tolerance, int priority,
1810 struct sk_buff_head *xmitq)
1811{
1812 struct tipc_mon_state *mstate = &l->mon_state;
1813 struct sk_buff_head *dfq = &l->deferdq;
1814 struct tipc_link *bcl = l->bc_rcvlink;
1815 struct tipc_msg *hdr;
1816 struct sk_buff *skb;
1817 bool node_up = link_is_up(bcl);
1818 u16 glen = 0, bc_rcvgap = 0;
1819 int dlen = 0;
1820 void *data;
1821
1822 /* Don't send protocol message during reset or link failover */
1823 if (tipc_link_is_blocked(l))
1824 return;
1825
1826 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1827 return;
1828
1829 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1830 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1831
1832 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1833 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1834 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1835 if (!skb)
1836 return;
1837
1838 hdr = buf_msg(skb);
1839 data = msg_data(hdr);
1840 msg_set_session(hdr, l->session);
1841 msg_set_bearer_id(hdr, l->bearer_id);
1842 msg_set_net_plane(hdr, l->net_plane);
1843 msg_set_next_sent(hdr, l->snd_nxt);
1844 msg_set_ack(hdr, l->rcv_nxt - 1);
1845 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1846 msg_set_bc_ack_invalid(hdr, !node_up);
1847 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1848 msg_set_link_tolerance(hdr, tolerance);
1849 msg_set_linkprio(hdr, priority);
1850 msg_set_redundant_link(hdr, node_up);
1851 msg_set_seq_gap(hdr, 0);
1852 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1853
1854 if (mtyp == STATE_MSG) {
1855 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1856 msg_set_seqno(hdr, l->snd_nxt_state++);
1857 msg_set_seq_gap(hdr, rcvgap);
1858 bc_rcvgap = link_bc_rcv_gap(bcl);
1859 msg_set_bc_gap(hdr, bc_rcvgap);
1860 msg_set_probe(hdr, probe);
1861 msg_set_is_keepalive(hdr, probe || probe_reply);
1862 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1863 glen = tipc_build_gap_ack_blks(l, hdr);
1864 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1865 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1866 skb_trim(skb, INT_H_SIZE + glen + dlen);
1867 l->stats.sent_states++;
1868 l->rcv_unacked = 0;
1869 } else {
1870 /* RESET_MSG or ACTIVATE_MSG */
1871 if (mtyp == ACTIVATE_MSG) {
1872 msg_set_dest_session_valid(hdr, 1);
1873 msg_set_dest_session(hdr, l->peer_session);
1874 }
1875 msg_set_max_pkt(hdr, l->advertised_mtu);
1876 strcpy(data, l->if_name);
1877 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1878 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1879 }
1880 if (probe)
1881 l->stats.sent_probes++;
1882 if (rcvgap)
1883 l->stats.sent_nacks++;
1884 if (bc_rcvgap)
1885 bcl->stats.sent_nacks++;
1886 skb->priority = TC_PRIO_CONTROL;
1887 __skb_queue_tail(xmitq, skb);
1888 trace_tipc_proto_build(skb, false, l->name);
1889}
1890
1891void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1892 struct sk_buff_head *xmitq)
1893{
1894 u32 onode = tipc_own_addr(l->net);
1895 struct tipc_msg *hdr, *ihdr;
1896 struct sk_buff_head tnlq;
1897 struct sk_buff *skb;
1898 u32 dnode = l->addr;
1899
1900 __skb_queue_head_init(&tnlq);
1901 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1902 INT_H_SIZE, BASIC_H_SIZE,
1903 dnode, onode, 0, 0, 0);
1904 if (!skb) {
1905 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1906 return;
1907 }
1908
1909 hdr = buf_msg(skb);
1910 msg_set_msgcnt(hdr, 1);
1911 msg_set_bearer_id(hdr, l->peer_bearer_id);
1912
1913 ihdr = (struct tipc_msg *)msg_data(hdr);
1914 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1915 BASIC_H_SIZE, dnode);
1916 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1917 __skb_queue_tail(&tnlq, skb);
1918 tipc_link_xmit(l, &tnlq, xmitq);
1919}
1920
1921/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1922 * with contents of the link's transmit and backlog queues.
1923 */
1924void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1925 int mtyp, struct sk_buff_head *xmitq)
1926{
1927 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1928 struct sk_buff *skb, *tnlskb;
1929 struct tipc_msg *hdr, tnlhdr;
1930 struct sk_buff_head *queue = &l->transmq;
1931 struct sk_buff_head tmpxq, tnlq, frags;
1932 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1933 bool pktcnt_need_update = false;
1934 u16 syncpt;
1935 int rc;
1936
1937 if (!tnl)
1938 return;
1939
1940 __skb_queue_head_init(&tnlq);
1941 /* Link Synching:
1942 * From now on, send only one single ("dummy") SYNCH message
1943 * to peer. The SYNCH message does not contain any data, just
1944 * a header conveying the synch point to the peer.
1945 */
1946 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1947 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1948 INT_H_SIZE, 0, l->addr,
1949 tipc_own_addr(l->net),
1950 0, 0, 0);
1951 if (!tnlskb) {
1952 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1953 link_co_err);
1954 return;
1955 }
1956
1957 hdr = buf_msg(tnlskb);
1958 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1959 msg_set_syncpt(hdr, syncpt);
1960 msg_set_bearer_id(hdr, l->peer_bearer_id);
1961 __skb_queue_tail(&tnlq, tnlskb);
1962 tipc_link_xmit(tnl, &tnlq, xmitq);
1963 return;
1964 }
1965
1966 __skb_queue_head_init(&tmpxq);
1967 __skb_queue_head_init(&frags);
1968 /* At least one packet required for safe algorithm => add dummy */
1969 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1970 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1971 0, 0, TIPC_ERR_NO_PORT);
1972 if (!skb) {
1973 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1974 return;
1975 }
1976 __skb_queue_tail(&tnlq, skb);
1977 tipc_link_xmit(l, &tnlq, &tmpxq);
1978 __skb_queue_purge(&tmpxq);
1979
1980 /* Initialize reusable tunnel packet header */
1981 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1982 mtyp, INT_H_SIZE, l->addr);
1983 if (mtyp == SYNCH_MSG)
1984 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
1985 else
1986 pktcnt = skb_queue_len(&l->transmq);
1987 pktcnt += skb_queue_len(&l->backlogq);
1988 msg_set_msgcnt(&tnlhdr, pktcnt);
1989 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1990tnl:
1991 /* Wrap each packet into a tunnel packet */
1992 skb_queue_walk(queue, skb) {
1993 hdr = buf_msg(skb);
1994 if (queue == &l->backlogq)
1995 msg_set_seqno(hdr, seqno++);
1996 pktlen = msg_size(hdr);
1997
1998 /* Tunnel link MTU is not large enough? This could be
1999 * due to:
2000 * 1) Link MTU has just changed or set differently;
2001 * 2) Or FAILOVER on the top of a SYNCH message
2002 *
2003 * The 2nd case should not happen if peer supports
2004 * TIPC_TUNNEL_ENHANCED
2005 */
2006 if (pktlen > tnl->mtu - INT_H_SIZE) {
2007 if (mtyp == FAILOVER_MSG &&
2008 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2009 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2010 &frags);
2011 if (rc) {
2012 pr_warn("%sunable to frag msg: rc %d\n",
2013 link_co_err, rc);
2014 return;
2015 }
2016 pktcnt += skb_queue_len(&frags) - 1;
2017 pktcnt_need_update = true;
2018 skb_queue_splice_tail_init(&frags, &tnlq);
2019 continue;
2020 }
2021 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2022 * => Just warn it and return!
2023 */
2024 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2025 link_co_err, msg_user(hdr),
2026 msg_type(hdr), msg_size(hdr));
2027 return;
2028 }
2029
2030 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2031 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2032 if (!tnlskb) {
2033 pr_warn("%sunable to send packet\n", link_co_err);
2034 return;
2035 }
2036 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2037 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2038 __skb_queue_tail(&tnlq, tnlskb);
2039 }
2040 if (queue != &l->backlogq) {
2041 queue = &l->backlogq;
2042 goto tnl;
2043 }
2044
2045 if (pktcnt_need_update)
2046 skb_queue_walk(&tnlq, skb) {
2047 hdr = buf_msg(skb);
2048 msg_set_msgcnt(hdr, pktcnt);
2049 }
2050
2051 tipc_link_xmit(tnl, &tnlq, xmitq);
2052
2053 if (mtyp == FAILOVER_MSG) {
2054 tnl->drop_point = l->rcv_nxt;
2055 tnl->failover_reasm_skb = l->reasm_buf;
2056 l->reasm_buf = NULL;
2057
2058 /* Failover the link's deferdq */
2059 if (unlikely(!skb_queue_empty(fdefq))) {
2060 pr_warn("Link failover deferdq not empty: %d!\n",
2061 skb_queue_len(fdefq));
2062 __skb_queue_purge(fdefq);
2063 }
2064 skb_queue_splice_init(&l->deferdq, fdefq);
2065 }
2066}
2067
2068/**
2069 * tipc_link_failover_prepare() - prepare tnl for link failover
2070 *
2071 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2072 * see the tipc_node_link_failover() for details
2073 *
2074 * @l: failover link
2075 * @tnl: tunnel link
2076 * @xmitq: queue for messages to be xmited
2077 */
2078void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2079 struct sk_buff_head *xmitq)
2080{
2081 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2082
2083 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2084
2085 /* This failover link endpoint was never established before,
2086 * so it has not received anything from peer.
2087 * Otherwise, it must be a normal failover situation or the
2088 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2089 * would have to start over from scratch instead.
2090 */
2091 tnl->drop_point = 1;
2092 tnl->failover_reasm_skb = NULL;
2093
2094 /* Initiate the link's failover deferdq */
2095 if (unlikely(!skb_queue_empty(fdefq))) {
2096 pr_warn("Link failover deferdq not empty: %d!\n",
2097 skb_queue_len(fdefq));
2098 __skb_queue_purge(fdefq);
2099 }
2100}
2101
2102/* tipc_link_validate_msg(): validate message against current link state
2103 * Returns true if message should be accepted, otherwise false
2104 */
2105bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2106{
2107 u16 curr_session = l->peer_session;
2108 u16 session = msg_session(hdr);
2109 int mtyp = msg_type(hdr);
2110
2111 if (msg_user(hdr) != LINK_PROTOCOL)
2112 return true;
2113
2114 switch (mtyp) {
2115 case RESET_MSG:
2116 if (!l->in_session)
2117 return true;
2118 /* Accept only RESET with new session number */
2119 return more(session, curr_session);
2120 case ACTIVATE_MSG:
2121 if (!l->in_session)
2122 return true;
2123 /* Accept only ACTIVATE with new or current session number */
2124 return !less(session, curr_session);
2125 case STATE_MSG:
2126 /* Accept only STATE with current session number */
2127 if (!l->in_session)
2128 return false;
2129 if (session != curr_session)
2130 return false;
2131 /* Extra sanity check */
2132 if (!link_is_up(l) && msg_ack(hdr))
2133 return false;
2134 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2135 return true;
2136 /* Accept only STATE with new sequence number */
2137 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2138 default:
2139 return false;
2140 }
2141}
2142
2143/* tipc_link_proto_rcv(): receive link level protocol message :
2144 * Note that network plane id propagates through the network, and may
2145 * change at any time. The node with lowest numerical id determines
2146 * network plane
2147 */
2148static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2149 struct sk_buff_head *xmitq)
2150{
2151 struct tipc_msg *hdr = buf_msg(skb);
2152 struct tipc_gap_ack_blks *ga = NULL;
2153 bool reply = msg_probe(hdr), retransmitted = false;
2154 u16 dlen = msg_data_sz(hdr), glen = 0;
2155 u16 peers_snd_nxt = msg_next_sent(hdr);
2156 u16 peers_tol = msg_link_tolerance(hdr);
2157 u16 peers_prio = msg_linkprio(hdr);
2158 u16 gap = msg_seq_gap(hdr);
2159 u16 ack = msg_ack(hdr);
2160 u16 rcv_nxt = l->rcv_nxt;
2161 u16 rcvgap = 0;
2162 int mtyp = msg_type(hdr);
2163 int rc = 0, released;
2164 char *if_name;
2165 void *data;
2166
2167 trace_tipc_proto_rcv(skb, false, l->name);
2168 if (tipc_link_is_blocked(l) || !xmitq)
2169 goto exit;
2170
2171 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2172 l->net_plane = msg_net_plane(hdr);
2173
2174 skb_linearize(skb);
2175 hdr = buf_msg(skb);
2176 data = msg_data(hdr);
2177
2178 if (!tipc_link_validate_msg(l, hdr)) {
2179 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2180 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2181 goto exit;
2182 }
2183
2184 switch (mtyp) {
2185 case RESET_MSG:
2186 case ACTIVATE_MSG:
2187 /* Complete own link name with peer's interface name */
2188 if_name = strrchr(l->name, ':') + 1;
2189 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2190 break;
2191 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2192 break;
2193 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2194
2195 /* Update own tolerance if peer indicates a non-zero value */
2196 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2197 l->tolerance = peers_tol;
2198 l->bc_rcvlink->tolerance = peers_tol;
2199 }
2200 /* Update own priority if peer's priority is higher */
2201 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2202 l->priority = peers_prio;
2203
2204 /* If peer is going down we want full re-establish cycle */
2205 if (msg_peer_stopping(hdr)) {
2206 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2207 break;
2208 }
2209
2210 /* If this endpoint was re-created while peer was ESTABLISHING
2211 * it doesn't know current session number. Force re-synch.
2212 */
2213 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2214 l->session != msg_dest_session(hdr)) {
2215 if (less(l->session, msg_dest_session(hdr)))
2216 l->session = msg_dest_session(hdr) + 1;
2217 break;
2218 }
2219
2220 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2221 if (mtyp == RESET_MSG || !link_is_up(l))
2222 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2223
2224 /* ACTIVATE_MSG takes up link if it was already locally reset */
2225 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2226 rc = TIPC_LINK_UP_EVT;
2227
2228 l->peer_session = msg_session(hdr);
2229 l->in_session = true;
2230 l->peer_bearer_id = msg_bearer_id(hdr);
2231 if (l->mtu > msg_max_pkt(hdr))
2232 l->mtu = msg_max_pkt(hdr);
2233 break;
2234
2235 case STATE_MSG:
2236 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2237
2238 /* Update own tolerance if peer indicates a non-zero value */
2239 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2240 l->tolerance = peers_tol;
2241 l->bc_rcvlink->tolerance = peers_tol;
2242 }
2243 /* Update own prio if peer indicates a different value */
2244 if ((peers_prio != l->priority) &&
2245 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2246 l->priority = peers_prio;
2247 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2248 }
2249
2250 l->silent_intv_cnt = 0;
2251 l->stats.recv_states++;
2252 if (msg_probe(hdr))
2253 l->stats.recv_probes++;
2254
2255 if (!link_is_up(l)) {
2256 if (l->state == LINK_ESTABLISHING)
2257 rc = TIPC_LINK_UP_EVT;
2258 break;
2259 }
2260
2261 /* Receive Gap ACK blocks from peer if any */
2262 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2263
2264 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2265 &l->mon_state, l->bearer_id);
2266
2267 /* Send NACK if peer has sent pkts we haven't received yet */
2268 if ((reply || msg_is_keepalive(hdr)) &&
2269 more(peers_snd_nxt, rcv_nxt) &&
2270 !tipc_link_is_synching(l) &&
2271 skb_queue_empty(&l->deferdq))
2272 rcvgap = peers_snd_nxt - l->rcv_nxt;
2273 if (rcvgap || reply)
2274 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2275 rcvgap, 0, 0, xmitq);
2276
2277 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2278 &retransmitted, &rc);
2279 if (gap)
2280 l->stats.recv_nacks++;
2281 if (released || retransmitted)
2282 tipc_link_update_cwin(l, released, retransmitted);
2283 if (released)
2284 tipc_link_advance_backlog(l, xmitq);
2285 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2286 link_prepare_wakeup(l);
2287 }
2288exit:
2289 kfree_skb(skb);
2290 return rc;
2291}
2292
2293/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2294 */
2295static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2296 u16 peers_snd_nxt,
2297 struct sk_buff_head *xmitq)
2298{
2299 struct sk_buff *skb;
2300 struct tipc_msg *hdr;
2301 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2302 u16 ack = l->rcv_nxt - 1;
2303 u16 gap_to = peers_snd_nxt - 1;
2304
2305 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2306 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2307 if (!skb)
2308 return false;
2309 hdr = buf_msg(skb);
2310 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2311 msg_set_bcast_ack(hdr, ack);
2312 msg_set_bcgap_after(hdr, ack);
2313 if (dfrd_skb)
2314 gap_to = buf_seqno(dfrd_skb) - 1;
2315 msg_set_bcgap_to(hdr, gap_to);
2316 msg_set_non_seq(hdr, bcast);
2317 __skb_queue_tail(xmitq, skb);
2318 return true;
2319}
2320
2321/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2322 *
2323 * Give a newly added peer node the sequence number where it should
2324 * start receiving and acking broadcast packets.
2325 */
2326static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2327 struct sk_buff_head *xmitq)
2328{
2329 struct sk_buff_head list;
2330
2331 __skb_queue_head_init(&list);
2332 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2333 return;
2334 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2335 tipc_link_xmit(l, &list, xmitq);
2336}
2337
2338/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2339 */
2340void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2341{
2342 int mtyp = msg_type(hdr);
2343 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2344
2345 if (link_is_up(l))
2346 return;
2347
2348 if (msg_user(hdr) == BCAST_PROTOCOL) {
2349 l->rcv_nxt = peers_snd_nxt;
2350 l->state = LINK_ESTABLISHED;
2351 return;
2352 }
2353
2354 if (l->peer_caps & TIPC_BCAST_SYNCH)
2355 return;
2356
2357 if (msg_peer_node_is_up(hdr))
2358 return;
2359
2360 /* Compatibility: accept older, less safe initial synch data */
2361 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2362 l->rcv_nxt = peers_snd_nxt;
2363}
2364
2365/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2366 */
2367int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2368 struct sk_buff_head *xmitq)
2369{
2370 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2371 int rc = 0;
2372
2373 if (!link_is_up(l))
2374 return rc;
2375
2376 if (!msg_peer_node_is_up(hdr))
2377 return rc;
2378
2379 /* Open when peer ackowledges our bcast init msg (pkt #1) */
2380 if (msg_ack(hdr))
2381 l->bc_peer_is_up = true;
2382
2383 if (!l->bc_peer_is_up)
2384 return rc;
2385
2386 /* Ignore if peers_snd_nxt goes beyond receive window */
2387 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2388 return rc;
2389
2390 l->snd_nxt = peers_snd_nxt;
2391 if (link_bc_rcv_gap(l))
2392 rc |= TIPC_LINK_SND_STATE;
2393
2394 /* Return now if sender supports nack via STATE messages */
2395 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2396 return rc;
2397
2398 /* Otherwise, be backwards compatible */
2399
2400 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2401 l->nack_state = BC_NACK_SND_CONDITIONAL;
2402 return 0;
2403 }
2404
2405 /* Don't NACK if one was recently sent or peeked */
2406 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2407 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2408 return 0;
2409 }
2410
2411 /* Conditionally delay NACK sending until next synch rcv */
2412 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2413 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2414 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2415 return 0;
2416 }
2417
2418 /* Send NACK now but suppress next one */
2419 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2420 l->nack_state = BC_NACK_SND_SUPPRESS;
2421 return 0;
2422}
2423
2424int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2425 struct tipc_gap_ack_blks *ga,
2426 struct sk_buff_head *xmitq,
2427 struct sk_buff_head *retrq)
2428{
2429 struct tipc_link *l = r->bc_sndlink;
2430 bool unused = false;
2431 int rc = 0;
2432
2433 if (!link_is_up(r) || !r->bc_peer_is_up)
2434 return 0;
2435
2436 if (gap) {
2437 l->stats.recv_nacks++;
2438 r->stats.recv_nacks++;
2439 }
2440
2441 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2442 return 0;
2443
2444 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2445 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2446
2447 tipc_link_advance_backlog(l, xmitq);
2448 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2449 link_prepare_wakeup(l);
2450
2451 return rc;
2452}
2453
2454/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2455 * This function is here for backwards compatibility, since
2456 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2457 */
2458int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2459 struct sk_buff_head *xmitq)
2460{
2461 struct tipc_msg *hdr = buf_msg(skb);
2462 u32 dnode = msg_destnode(hdr);
2463 int mtyp = msg_type(hdr);
2464 u16 acked = msg_bcast_ack(hdr);
2465 u16 from = acked + 1;
2466 u16 to = msg_bcgap_to(hdr);
2467 u16 peers_snd_nxt = to + 1;
2468 int rc = 0;
2469
2470 kfree_skb(skb);
2471
2472 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2473 return 0;
2474
2475 if (mtyp != STATE_MSG)
2476 return 0;
2477
2478 if (dnode == tipc_own_addr(l->net)) {
2479 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2480 xmitq);
2481 l->stats.recv_nacks++;
2482 return rc;
2483 }
2484
2485 /* Msg for other node => suppress own NACK at next sync if applicable */
2486 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2487 l->nack_state = BC_NACK_SND_SUPPRESS;
2488
2489 return 0;
2490}
2491
2492void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2493{
2494 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2495
2496 l->min_win = min_win;
2497 l->ssthresh = max_win;
2498 l->max_win = max_win;
2499 l->window = min_win;
2500 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2501 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2502 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2503 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2504 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2505}
2506
2507/**
2508 * link_reset_stats - reset link statistics
2509 * @l: pointer to link
2510 */
2511void tipc_link_reset_stats(struct tipc_link *l)
2512{
2513 memset(&l->stats, 0, sizeof(l->stats));
2514}
2515
2516static void link_print(struct tipc_link *l, const char *str)
2517{
2518 struct sk_buff *hskb = skb_peek(&l->transmq);
2519 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2520 u16 tail = l->snd_nxt - 1;
2521
2522 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2523 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2524 skb_queue_len(&l->transmq), head, tail,
2525 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2526}
2527
2528/* Parse and validate nested (link) properties valid for media, bearer and link
2529 */
2530int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2531{
2532 int err;
2533
2534 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2535 tipc_nl_prop_policy, NULL);
2536 if (err)
2537 return err;
2538
2539 if (props[TIPC_NLA_PROP_PRIO]) {
2540 u32 prio;
2541
2542 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2543 if (prio > TIPC_MAX_LINK_PRI)
2544 return -EINVAL;
2545 }
2546
2547 if (props[TIPC_NLA_PROP_TOL]) {
2548 u32 tol;
2549
2550 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2551 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2552 return -EINVAL;
2553 }
2554
2555 if (props[TIPC_NLA_PROP_WIN]) {
2556 u32 max_win;
2557
2558 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2559 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2560 return -EINVAL;
2561 }
2562
2563 return 0;
2564}
2565
2566static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2567{
2568 int i;
2569 struct nlattr *stats;
2570
2571 struct nla_map {
2572 u32 key;
2573 u32 val;
2574 };
2575
2576 struct nla_map map[] = {
2577 {TIPC_NLA_STATS_RX_INFO, 0},
2578 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2579 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2580 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2581 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2582 {TIPC_NLA_STATS_TX_INFO, 0},
2583 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2584 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2585 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2586 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2587 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2588 s->msg_length_counts : 1},
2589 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2590 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2591 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2592 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2593 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2594 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2595 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2596 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2597 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2598 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2599 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2600 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2601 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2602 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2603 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2604 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2605 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2606 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2607 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2608 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2609 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2610 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2611 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2612 };
2613
2614 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2615 if (!stats)
2616 return -EMSGSIZE;
2617
2618 for (i = 0; i < ARRAY_SIZE(map); i++)
2619 if (nla_put_u32(skb, map[i].key, map[i].val))
2620 goto msg_full;
2621
2622 nla_nest_end(skb, stats);
2623
2624 return 0;
2625msg_full:
2626 nla_nest_cancel(skb, stats);
2627
2628 return -EMSGSIZE;
2629}
2630
2631/* Caller should hold appropriate locks to protect the link */
2632int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2633 struct tipc_link *link, int nlflags)
2634{
2635 u32 self = tipc_own_addr(net);
2636 struct nlattr *attrs;
2637 struct nlattr *prop;
2638 void *hdr;
2639 int err;
2640
2641 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2642 nlflags, TIPC_NL_LINK_GET);
2643 if (!hdr)
2644 return -EMSGSIZE;
2645
2646 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2647 if (!attrs)
2648 goto msg_full;
2649
2650 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2651 goto attr_msg_full;
2652 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2653 goto attr_msg_full;
2654 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2655 goto attr_msg_full;
2656 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2657 goto attr_msg_full;
2658 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2659 goto attr_msg_full;
2660
2661 if (tipc_link_is_up(link))
2662 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2663 goto attr_msg_full;
2664 if (link->active)
2665 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2666 goto attr_msg_full;
2667
2668 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2669 if (!prop)
2670 goto attr_msg_full;
2671 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2672 goto prop_msg_full;
2673 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2674 goto prop_msg_full;
2675 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2676 link->window))
2677 goto prop_msg_full;
2678 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2679 goto prop_msg_full;
2680 nla_nest_end(msg->skb, prop);
2681
2682 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2683 if (err)
2684 goto attr_msg_full;
2685
2686 nla_nest_end(msg->skb, attrs);
2687 genlmsg_end(msg->skb, hdr);
2688
2689 return 0;
2690
2691prop_msg_full:
2692 nla_nest_cancel(msg->skb, prop);
2693attr_msg_full:
2694 nla_nest_cancel(msg->skb, attrs);
2695msg_full:
2696 genlmsg_cancel(msg->skb, hdr);
2697
2698 return -EMSGSIZE;
2699}
2700
2701static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2702 struct tipc_stats *stats)
2703{
2704 int i;
2705 struct nlattr *nest;
2706
2707 struct nla_map {
2708 __u32 key;
2709 __u32 val;
2710 };
2711
2712 struct nla_map map[] = {
2713 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2714 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2715 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2716 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2717 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2718 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2719 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2720 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2721 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2722 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2723 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2724 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2725 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2726 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2727 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2728 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2729 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2730 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2731 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2732 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2733 };
2734
2735 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2736 if (!nest)
2737 return -EMSGSIZE;
2738
2739 for (i = 0; i < ARRAY_SIZE(map); i++)
2740 if (nla_put_u32(skb, map[i].key, map[i].val))
2741 goto msg_full;
2742
2743 nla_nest_end(skb, nest);
2744
2745 return 0;
2746msg_full:
2747 nla_nest_cancel(skb, nest);
2748
2749 return -EMSGSIZE;
2750}
2751
2752int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2753 struct tipc_link *bcl)
2754{
2755 int err;
2756 void *hdr;
2757 struct nlattr *attrs;
2758 struct nlattr *prop;
2759 u32 bc_mode = tipc_bcast_get_mode(net);
2760 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2761
2762 if (!bcl)
2763 return 0;
2764
2765 tipc_bcast_lock(net);
2766
2767 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2768 NLM_F_MULTI, TIPC_NL_LINK_GET);
2769 if (!hdr) {
2770 tipc_bcast_unlock(net);
2771 return -EMSGSIZE;
2772 }
2773
2774 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2775 if (!attrs)
2776 goto msg_full;
2777
2778 /* The broadcast link is always up */
2779 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2780 goto attr_msg_full;
2781
2782 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2783 goto attr_msg_full;
2784 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2785 goto attr_msg_full;
2786 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2787 goto attr_msg_full;
2788 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2789 goto attr_msg_full;
2790
2791 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2792 if (!prop)
2793 goto attr_msg_full;
2794 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2795 goto prop_msg_full;
2796 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2797 goto prop_msg_full;
2798 if (bc_mode & BCLINK_MODE_SEL)
2799 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2800 bc_ratio))
2801 goto prop_msg_full;
2802 nla_nest_end(msg->skb, prop);
2803
2804 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2805 if (err)
2806 goto attr_msg_full;
2807
2808 tipc_bcast_unlock(net);
2809 nla_nest_end(msg->skb, attrs);
2810 genlmsg_end(msg->skb, hdr);
2811
2812 return 0;
2813
2814prop_msg_full:
2815 nla_nest_cancel(msg->skb, prop);
2816attr_msg_full:
2817 nla_nest_cancel(msg->skb, attrs);
2818msg_full:
2819 tipc_bcast_unlock(net);
2820 genlmsg_cancel(msg->skb, hdr);
2821
2822 return -EMSGSIZE;
2823}
2824
2825void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2826 struct sk_buff_head *xmitq)
2827{
2828 l->tolerance = tol;
2829 if (l->bc_rcvlink)
2830 l->bc_rcvlink->tolerance = tol;
2831 if (link_is_up(l))
2832 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2833}
2834
2835void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2836 struct sk_buff_head *xmitq)
2837{
2838 l->priority = prio;
2839 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2840}
2841
2842void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2843{
2844 l->abort_limit = limit;
2845}
2846
2847/**
2848 * tipc_link_dump - dump TIPC link data
2849 * @l: tipc link to be dumped
2850 * @dqueues: bitmask to decide if any link queue to be dumped?
2851 * - TIPC_DUMP_NONE: don't dump link queues
2852 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2853 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2854 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2855 * - TIPC_DUMP_INPUTQ: dump link input queue
2856 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2857 * - TIPC_DUMP_ALL: dump all the link queues above
2858 * @buf: returned buffer of dump data in format
2859 */
2860int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2861{
2862 int i = 0;
2863 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2864 struct sk_buff_head *list;
2865 struct sk_buff *hskb, *tskb;
2866 u32 len;
2867
2868 if (!l) {
2869 i += scnprintf(buf, sz, "link data: (null)\n");
2870 return i;
2871 }
2872
2873 i += scnprintf(buf, sz, "link data: %x", l->addr);
2874 i += scnprintf(buf + i, sz - i, " %x", l->state);
2875 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2876 i += scnprintf(buf + i, sz - i, " %u", l->session);
2877 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2878 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2879 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2880 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2881 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2882 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2883 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2884 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2885 i += scnprintf(buf + i, sz - i, " %u", 0);
2886 i += scnprintf(buf + i, sz - i, " %u", 0);
2887 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2888
2889 list = &l->transmq;
2890 len = skb_queue_len(list);
2891 hskb = skb_peek(list);
2892 tskb = skb_peek_tail(list);
2893 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2894 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2895 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2896
2897 list = &l->deferdq;
2898 len = skb_queue_len(list);
2899 hskb = skb_peek(list);
2900 tskb = skb_peek_tail(list);
2901 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2902 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2903 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2904
2905 list = &l->backlogq;
2906 len = skb_queue_len(list);
2907 hskb = skb_peek(list);
2908 tskb = skb_peek_tail(list);
2909 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2910 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2911 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2912
2913 list = l->inputq;
2914 len = skb_queue_len(list);
2915 hskb = skb_peek(list);
2916 tskb = skb_peek_tail(list);
2917 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2918 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2919 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2920
2921 if (dqueues & TIPC_DUMP_TRANSMQ) {
2922 i += scnprintf(buf + i, sz - i, "transmq: ");
2923 i += tipc_list_dump(&l->transmq, false, buf + i);
2924 }
2925 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2926 i += scnprintf(buf + i, sz - i,
2927 "backlogq: <%u %u %u %u %u>, ",
2928 l->backlog[TIPC_LOW_IMPORTANCE].len,
2929 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2930 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2931 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2932 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2933 i += tipc_list_dump(&l->backlogq, false, buf + i);
2934 }
2935 if (dqueues & TIPC_DUMP_DEFERDQ) {
2936 i += scnprintf(buf + i, sz - i, "deferdq: ");
2937 i += tipc_list_dump(&l->deferdq, false, buf + i);
2938 }
2939 if (dqueues & TIPC_DUMP_INPUTQ) {
2940 i += scnprintf(buf + i, sz - i, "inputq: ");
2941 i += tipc_list_dump(l->inputq, false, buf + i);
2942 }
2943 if (dqueues & TIPC_DUMP_WAKEUP) {
2944 i += scnprintf(buf + i, sz - i, "wakeup: ");
2945 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2946 }
2947
2948 return i;
2949}
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
51struct 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 * @net: pointer to namespace struct
86 * @peer_session: link session # being used by peer end of link
87 * @peer_bearer_id: bearer id used by link's peer endpoint
88 * @bearer_id: local bearer id used by link
89 * @tolerance: minimum link continuity loss needed to reset link [in ms]
90 * @abort_limit: # of unacknowledged continuity probes needed to reset link
91 * @state: current state of link FSM
92 * @peer_caps: bitmap describing capabilities of peer node
93 * @silent_intv_cnt: # of timer intervals without any reception from peer
94 * @priority: current link priority
95 * @net_plane: current link network plane ('A' through 'H')
96 * @mon_state: cookie with information needed by link monitor
97 * @mtu: current maximum packet size for this link
98 * @advertised_mtu: advertised own mtu when link is being established
99 * @backlogq: queue for messages waiting to be sent
100 * @ackers: # of peers that needs to ack each packet before it can be released
101 * @acked: # last packet acked by a certain peer. Used for broadcast.
102 * @rcv_nxt: next sequence number to expect for inbound messages
103 * @inputq: buffer queue for messages to be delivered upwards
104 * @namedq: buffer queue for name table messages to be delivered upwards
105 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
106 * @reasm_buf: head of partially reassembled inbound message fragments
107 * @stats: collects statistics regarding link activity
108 * @session: session to be used by link
109 * @snd_nxt_state: next send seq number
110 * @rcv_nxt_state: next rcv seq number
111 * @in_session: have received ACTIVATE_MSG from peer
112 * @active: link is active
113 * @if_name: associated interface name
114 * @rst_cnt: link reset counter
115 * @drop_point: seq number for failover handling (FIXME)
116 * @failover_reasm_skb: saved failover msg ptr (FIXME)
117 * @failover_deferdq: deferred message queue for failover processing (FIXME)
118 * @transmq: the link's transmit queue
119 * @backlog: link's backlog by priority (importance)
120 * @snd_nxt: next sequence number to be used
121 * @rcv_unacked: # messages read by user, but not yet acked back to peer
122 * @deferdq: deferred receive queue
123 * @window: sliding window size for congestion handling
124 * @min_win: minimal send window to be used by link
125 * @ssthresh: slow start threshold for congestion handling
126 * @max_win: maximal send window to be used by link
127 * @cong_acks: congestion acks for congestion avoidance (FIXME)
128 * @checkpoint: seq number for congestion window size handling
129 * @reasm_tnlmsg: fragmentation/reassembly area for tunnel protocol message
130 * @last_gap: last gap ack blocks for bcast (FIXME)
131 * @last_ga: ptr to gap ack blocks
132 * @bc_rcvlink: the peer specific link used for broadcast reception
133 * @bc_sndlink: the namespace global link used for broadcast sending
134 * @nack_state: bcast nack state
135 * @bc_peer_is_up: peer has acked the bcast init msg
136 */
137struct tipc_link {
138 u32 addr;
139 char name[TIPC_MAX_LINK_NAME];
140 struct net *net;
141
142 /* Management and link supervision data */
143 u16 peer_session;
144 u16 session;
145 u16 snd_nxt_state;
146 u16 rcv_nxt_state;
147 u32 peer_bearer_id;
148 u32 bearer_id;
149 u32 tolerance;
150 u32 abort_limit;
151 u32 state;
152 u16 peer_caps;
153 bool in_session;
154 bool active;
155 u32 silent_intv_cnt;
156 char if_name[TIPC_MAX_IF_NAME];
157 u32 priority;
158 char net_plane;
159 struct tipc_mon_state mon_state;
160 u16 rst_cnt;
161
162 /* Failover/synch */
163 u16 drop_point;
164 struct sk_buff *failover_reasm_skb;
165 struct sk_buff_head failover_deferdq;
166
167 /* Max packet negotiation */
168 u16 mtu;
169 u16 advertised_mtu;
170
171 /* Sending */
172 struct sk_buff_head transmq;
173 struct sk_buff_head backlogq;
174 struct {
175 u16 len;
176 u16 limit;
177 struct sk_buff *target_bskb;
178 } backlog[5];
179 u16 snd_nxt;
180
181 /* Reception */
182 u16 rcv_nxt;
183 u32 rcv_unacked;
184 struct sk_buff_head deferdq;
185 struct sk_buff_head *inputq;
186 struct sk_buff_head *namedq;
187
188 /* Congestion handling */
189 struct sk_buff_head wakeupq;
190 u16 window;
191 u16 min_win;
192 u16 ssthresh;
193 u16 max_win;
194 u16 cong_acks;
195 u16 checkpoint;
196
197 /* Fragmentation/reassembly */
198 struct sk_buff *reasm_buf;
199 struct sk_buff *reasm_tnlmsg;
200
201 /* Broadcast */
202 u16 ackers;
203 u16 acked;
204 u16 last_gap;
205 struct tipc_gap_ack_blks *last_ga;
206 struct tipc_link *bc_rcvlink;
207 struct tipc_link *bc_sndlink;
208 u8 nack_state;
209 bool bc_peer_is_up;
210
211 /* Statistics */
212 struct tipc_stats stats;
213};
214
215/*
216 * Error message prefixes
217 */
218static const char *link_co_err = "Link tunneling error, ";
219static const char *link_rst_msg = "Resetting link ";
220
221/* Send states for broadcast NACKs
222 */
223enum {
224 BC_NACK_SND_CONDITIONAL,
225 BC_NACK_SND_UNCONDITIONAL,
226 BC_NACK_SND_SUPPRESS,
227};
228
229#define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
230#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
231
232/* Link FSM states:
233 */
234enum {
235 LINK_ESTABLISHED = 0xe,
236 LINK_ESTABLISHING = 0xe << 4,
237 LINK_RESET = 0x1 << 8,
238 LINK_RESETTING = 0x2 << 12,
239 LINK_PEER_RESET = 0xd << 16,
240 LINK_FAILINGOVER = 0xf << 20,
241 LINK_SYNCHING = 0xc << 24
242};
243
244static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
245 struct sk_buff_head *xmitq);
246static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
247 bool probe_reply, u16 rcvgap,
248 int tolerance, int priority,
249 struct sk_buff_head *xmitq);
250static void link_print(struct tipc_link *l, const char *str);
251static int tipc_link_build_nack_msg(struct tipc_link *l,
252 struct sk_buff_head *xmitq);
253static void tipc_link_build_bc_init_msg(struct tipc_link *l,
254 struct sk_buff_head *xmitq);
255static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
256 struct tipc_link *l, u8 start_index);
257static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
258static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
259 u16 acked, u16 gap,
260 struct tipc_gap_ack_blks *ga,
261 struct sk_buff_head *xmitq,
262 bool *retransmitted, int *rc);
263static void tipc_link_update_cwin(struct tipc_link *l, int released,
264 bool retransmitted);
265/*
266 * Simple non-static link routines (i.e. referenced outside this file)
267 */
268bool tipc_link_is_up(struct tipc_link *l)
269{
270 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
271}
272
273bool tipc_link_peer_is_down(struct tipc_link *l)
274{
275 return l->state == LINK_PEER_RESET;
276}
277
278bool tipc_link_is_reset(struct tipc_link *l)
279{
280 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
281}
282
283bool tipc_link_is_establishing(struct tipc_link *l)
284{
285 return l->state == LINK_ESTABLISHING;
286}
287
288bool tipc_link_is_synching(struct tipc_link *l)
289{
290 return l->state == LINK_SYNCHING;
291}
292
293bool tipc_link_is_failingover(struct tipc_link *l)
294{
295 return l->state == LINK_FAILINGOVER;
296}
297
298bool tipc_link_is_blocked(struct tipc_link *l)
299{
300 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
301}
302
303static bool link_is_bc_sndlink(struct tipc_link *l)
304{
305 return !l->bc_sndlink;
306}
307
308static bool link_is_bc_rcvlink(struct tipc_link *l)
309{
310 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
311}
312
313void tipc_link_set_active(struct tipc_link *l, bool active)
314{
315 l->active = active;
316}
317
318u32 tipc_link_id(struct tipc_link *l)
319{
320 return l->peer_bearer_id << 16 | l->bearer_id;
321}
322
323int tipc_link_min_win(struct tipc_link *l)
324{
325 return l->min_win;
326}
327
328int tipc_link_max_win(struct tipc_link *l)
329{
330 return l->max_win;
331}
332
333int tipc_link_prio(struct tipc_link *l)
334{
335 return l->priority;
336}
337
338unsigned long tipc_link_tolerance(struct tipc_link *l)
339{
340 return l->tolerance;
341}
342
343struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
344{
345 return l->inputq;
346}
347
348char tipc_link_plane(struct tipc_link *l)
349{
350 return l->net_plane;
351}
352
353struct net *tipc_link_net(struct tipc_link *l)
354{
355 return l->net;
356}
357
358void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
359{
360 l->peer_caps = capabilities;
361}
362
363void tipc_link_add_bc_peer(struct tipc_link *snd_l,
364 struct tipc_link *uc_l,
365 struct sk_buff_head *xmitq)
366{
367 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
368
369 snd_l->ackers++;
370 rcv_l->acked = snd_l->snd_nxt - 1;
371 snd_l->state = LINK_ESTABLISHED;
372 tipc_link_build_bc_init_msg(uc_l, xmitq);
373}
374
375void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
376 struct tipc_link *rcv_l,
377 struct sk_buff_head *xmitq)
378{
379 u16 ack = snd_l->snd_nxt - 1;
380
381 snd_l->ackers--;
382 rcv_l->bc_peer_is_up = true;
383 rcv_l->state = LINK_ESTABLISHED;
384 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
385 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
386 tipc_link_reset(rcv_l);
387 rcv_l->state = LINK_RESET;
388 if (!snd_l->ackers) {
389 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
390 tipc_link_reset(snd_l);
391 snd_l->state = LINK_RESET;
392 __skb_queue_purge(xmitq);
393 }
394}
395
396int tipc_link_bc_peers(struct tipc_link *l)
397{
398 return l->ackers;
399}
400
401static u16 link_bc_rcv_gap(struct tipc_link *l)
402{
403 struct sk_buff *skb = skb_peek(&l->deferdq);
404 u16 gap = 0;
405
406 if (more(l->snd_nxt, l->rcv_nxt))
407 gap = l->snd_nxt - l->rcv_nxt;
408 if (skb)
409 gap = buf_seqno(skb) - l->rcv_nxt;
410 return gap;
411}
412
413void tipc_link_set_mtu(struct tipc_link *l, int mtu)
414{
415 l->mtu = mtu;
416}
417
418int tipc_link_mtu(struct tipc_link *l)
419{
420 return l->mtu;
421}
422
423int tipc_link_mss(struct tipc_link *l)
424{
425#ifdef CONFIG_TIPC_CRYPTO
426 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
427#else
428 return l->mtu - INT_H_SIZE;
429#endif
430}
431
432u16 tipc_link_rcv_nxt(struct tipc_link *l)
433{
434 return l->rcv_nxt;
435}
436
437u16 tipc_link_acked(struct tipc_link *l)
438{
439 return l->acked;
440}
441
442char *tipc_link_name(struct tipc_link *l)
443{
444 return l->name;
445}
446
447u32 tipc_link_state(struct tipc_link *l)
448{
449 return l->state;
450}
451
452/**
453 * tipc_link_create - create a new link
454 * @net: pointer to associated network namespace
455 * @if_name: associated interface name
456 * @bearer_id: id (index) of associated bearer
457 * @tolerance: link tolerance to be used by link
458 * @net_plane: network plane (A,B,c..) this link belongs to
459 * @mtu: mtu to be advertised by link
460 * @priority: priority to be used by link
461 * @min_win: minimal send window to be used by link
462 * @max_win: maximal send window to be used by link
463 * @session: session to be used by link
464 * @peer: node id of peer node
465 * @peer_caps: bitmap describing peer node capabilities
466 * @bc_sndlink: the namespace global link used for broadcast sending
467 * @bc_rcvlink: the peer specific link used for broadcast reception
468 * @inputq: queue to put messages ready for delivery
469 * @namedq: queue to put binding table update messages ready for delivery
470 * @link: return value, pointer to put the created link
471 * @self: local unicast link id
472 * @peer_id: 128-bit ID of peer
473 *
474 * Return: true if link was created, otherwise false
475 */
476bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
477 int tolerance, char net_plane, u32 mtu, int priority,
478 u32 min_win, u32 max_win, u32 session, u32 self,
479 u32 peer, u8 *peer_id, u16 peer_caps,
480 struct tipc_link *bc_sndlink,
481 struct tipc_link *bc_rcvlink,
482 struct sk_buff_head *inputq,
483 struct sk_buff_head *namedq,
484 struct tipc_link **link)
485{
486 char peer_str[NODE_ID_STR_LEN] = {0,};
487 char self_str[NODE_ID_STR_LEN] = {0,};
488 struct tipc_link *l;
489
490 l = kzalloc(sizeof(*l), GFP_ATOMIC);
491 if (!l)
492 return false;
493 *link = l;
494 l->session = session;
495
496 /* Set link name for unicast links only */
497 if (peer_id) {
498 tipc_nodeid2string(self_str, tipc_own_id(net));
499 if (strlen(self_str) > 16)
500 sprintf(self_str, "%x", self);
501 tipc_nodeid2string(peer_str, peer_id);
502 if (strlen(peer_str) > 16)
503 sprintf(peer_str, "%x", peer);
504 }
505 /* Peer i/f name will be completed by reset/activate message */
506 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
507 self_str, if_name, peer_str);
508
509 strcpy(l->if_name, if_name);
510 l->addr = peer;
511 l->peer_caps = peer_caps;
512 l->net = net;
513 l->in_session = false;
514 l->bearer_id = bearer_id;
515 l->tolerance = tolerance;
516 if (bc_rcvlink)
517 bc_rcvlink->tolerance = tolerance;
518 l->net_plane = net_plane;
519 l->advertised_mtu = mtu;
520 l->mtu = mtu;
521 l->priority = priority;
522 tipc_link_set_queue_limits(l, min_win, max_win);
523 l->ackers = 1;
524 l->bc_sndlink = bc_sndlink;
525 l->bc_rcvlink = bc_rcvlink;
526 l->inputq = inputq;
527 l->namedq = namedq;
528 l->state = LINK_RESETTING;
529 __skb_queue_head_init(&l->transmq);
530 __skb_queue_head_init(&l->backlogq);
531 __skb_queue_head_init(&l->deferdq);
532 __skb_queue_head_init(&l->failover_deferdq);
533 skb_queue_head_init(&l->wakeupq);
534 skb_queue_head_init(l->inputq);
535 return true;
536}
537
538/**
539 * tipc_link_bc_create - create new link to be used for broadcast
540 * @net: pointer to associated network namespace
541 * @mtu: mtu to be used initially if no peers
542 * @min_win: minimal send window to be used by link
543 * @max_win: maximal send window to be used by link
544 * @inputq: queue to put messages ready for delivery
545 * @namedq: queue to put binding table update messages ready for delivery
546 * @link: return value, pointer to put the created link
547 * @ownnode: identity of own node
548 * @peer: node id of peer node
549 * @peer_id: 128-bit ID of peer
550 * @peer_caps: bitmap describing peer node capabilities
551 * @bc_sndlink: the namespace global link used for broadcast sending
552 *
553 * Return: true if link was created, otherwise false
554 */
555bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
556 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
557 struct sk_buff_head *inputq,
558 struct sk_buff_head *namedq,
559 struct tipc_link *bc_sndlink,
560 struct tipc_link **link)
561{
562 struct tipc_link *l;
563
564 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
565 max_win, 0, ownnode, peer, NULL, peer_caps,
566 bc_sndlink, NULL, inputq, namedq, link))
567 return false;
568
569 l = *link;
570 if (peer_id) {
571 char peer_str[NODE_ID_STR_LEN] = {0,};
572
573 tipc_nodeid2string(peer_str, peer_id);
574 if (strlen(peer_str) > 16)
575 sprintf(peer_str, "%x", peer);
576 /* Broadcast receiver link name: "broadcast-link:<peer>" */
577 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
578 peer_str);
579 } else {
580 strcpy(l->name, tipc_bclink_name);
581 }
582 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
583 tipc_link_reset(l);
584 l->state = LINK_RESET;
585 l->ackers = 0;
586 l->bc_rcvlink = l;
587
588 /* Broadcast send link is always up */
589 if (link_is_bc_sndlink(l))
590 l->state = LINK_ESTABLISHED;
591
592 /* Disable replicast if even a single peer doesn't support it */
593 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
594 tipc_bcast_toggle_rcast(net, false);
595
596 return true;
597}
598
599/**
600 * tipc_link_fsm_evt - link finite state machine
601 * @l: pointer to link
602 * @evt: state machine event to be processed
603 */
604int tipc_link_fsm_evt(struct tipc_link *l, int evt)
605{
606 int rc = 0;
607 int old_state = l->state;
608
609 switch (l->state) {
610 case LINK_RESETTING:
611 switch (evt) {
612 case LINK_PEER_RESET_EVT:
613 l->state = LINK_PEER_RESET;
614 break;
615 case LINK_RESET_EVT:
616 l->state = LINK_RESET;
617 break;
618 case LINK_FAILURE_EVT:
619 case LINK_FAILOVER_BEGIN_EVT:
620 case LINK_ESTABLISH_EVT:
621 case LINK_FAILOVER_END_EVT:
622 case LINK_SYNCH_BEGIN_EVT:
623 case LINK_SYNCH_END_EVT:
624 default:
625 goto illegal_evt;
626 }
627 break;
628 case LINK_RESET:
629 switch (evt) {
630 case LINK_PEER_RESET_EVT:
631 l->state = LINK_ESTABLISHING;
632 break;
633 case LINK_FAILOVER_BEGIN_EVT:
634 l->state = LINK_FAILINGOVER;
635 break;
636 case LINK_FAILURE_EVT:
637 case LINK_RESET_EVT:
638 case LINK_ESTABLISH_EVT:
639 case LINK_FAILOVER_END_EVT:
640 break;
641 case LINK_SYNCH_BEGIN_EVT:
642 case LINK_SYNCH_END_EVT:
643 default:
644 goto illegal_evt;
645 }
646 break;
647 case LINK_PEER_RESET:
648 switch (evt) {
649 case LINK_RESET_EVT:
650 l->state = LINK_ESTABLISHING;
651 break;
652 case LINK_PEER_RESET_EVT:
653 case LINK_ESTABLISH_EVT:
654 case LINK_FAILURE_EVT:
655 break;
656 case LINK_SYNCH_BEGIN_EVT:
657 case LINK_SYNCH_END_EVT:
658 case LINK_FAILOVER_BEGIN_EVT:
659 case LINK_FAILOVER_END_EVT:
660 default:
661 goto illegal_evt;
662 }
663 break;
664 case LINK_FAILINGOVER:
665 switch (evt) {
666 case LINK_FAILOVER_END_EVT:
667 l->state = LINK_RESET;
668 break;
669 case LINK_PEER_RESET_EVT:
670 case LINK_RESET_EVT:
671 case LINK_ESTABLISH_EVT:
672 case LINK_FAILURE_EVT:
673 break;
674 case LINK_FAILOVER_BEGIN_EVT:
675 case LINK_SYNCH_BEGIN_EVT:
676 case LINK_SYNCH_END_EVT:
677 default:
678 goto illegal_evt;
679 }
680 break;
681 case LINK_ESTABLISHING:
682 switch (evt) {
683 case LINK_ESTABLISH_EVT:
684 l->state = LINK_ESTABLISHED;
685 break;
686 case LINK_FAILOVER_BEGIN_EVT:
687 l->state = LINK_FAILINGOVER;
688 break;
689 case LINK_RESET_EVT:
690 l->state = LINK_RESET;
691 break;
692 case LINK_FAILURE_EVT:
693 case LINK_PEER_RESET_EVT:
694 case LINK_SYNCH_BEGIN_EVT:
695 case LINK_FAILOVER_END_EVT:
696 break;
697 case LINK_SYNCH_END_EVT:
698 default:
699 goto illegal_evt;
700 }
701 break;
702 case LINK_ESTABLISHED:
703 switch (evt) {
704 case LINK_PEER_RESET_EVT:
705 l->state = LINK_PEER_RESET;
706 rc |= TIPC_LINK_DOWN_EVT;
707 break;
708 case LINK_FAILURE_EVT:
709 l->state = LINK_RESETTING;
710 rc |= TIPC_LINK_DOWN_EVT;
711 break;
712 case LINK_RESET_EVT:
713 l->state = LINK_RESET;
714 break;
715 case LINK_ESTABLISH_EVT:
716 case LINK_SYNCH_END_EVT:
717 break;
718 case LINK_SYNCH_BEGIN_EVT:
719 l->state = LINK_SYNCHING;
720 break;
721 case LINK_FAILOVER_BEGIN_EVT:
722 case LINK_FAILOVER_END_EVT:
723 default:
724 goto illegal_evt;
725 }
726 break;
727 case LINK_SYNCHING:
728 switch (evt) {
729 case LINK_PEER_RESET_EVT:
730 l->state = LINK_PEER_RESET;
731 rc |= TIPC_LINK_DOWN_EVT;
732 break;
733 case LINK_FAILURE_EVT:
734 l->state = LINK_RESETTING;
735 rc |= TIPC_LINK_DOWN_EVT;
736 break;
737 case LINK_RESET_EVT:
738 l->state = LINK_RESET;
739 break;
740 case LINK_ESTABLISH_EVT:
741 case LINK_SYNCH_BEGIN_EVT:
742 break;
743 case LINK_SYNCH_END_EVT:
744 l->state = LINK_ESTABLISHED;
745 break;
746 case LINK_FAILOVER_BEGIN_EVT:
747 case LINK_FAILOVER_END_EVT:
748 default:
749 goto illegal_evt;
750 }
751 break;
752 default:
753 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
754 }
755 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
756 return rc;
757illegal_evt:
758 pr_err("Illegal FSM event %x in state %x on link %s\n",
759 evt, l->state, l->name);
760 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
761 return rc;
762}
763
764/* link_profile_stats - update statistical profiling of traffic
765 */
766static void link_profile_stats(struct tipc_link *l)
767{
768 struct sk_buff *skb;
769 struct tipc_msg *msg;
770 int length;
771
772 /* Update counters used in statistical profiling of send traffic */
773 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
774 l->stats.queue_sz_counts++;
775
776 skb = skb_peek(&l->transmq);
777 if (!skb)
778 return;
779 msg = buf_msg(skb);
780 length = msg_size(msg);
781
782 if (msg_user(msg) == MSG_FRAGMENTER) {
783 if (msg_type(msg) != FIRST_FRAGMENT)
784 return;
785 length = msg_size(msg_inner_hdr(msg));
786 }
787 l->stats.msg_lengths_total += length;
788 l->stats.msg_length_counts++;
789 if (length <= 64)
790 l->stats.msg_length_profile[0]++;
791 else if (length <= 256)
792 l->stats.msg_length_profile[1]++;
793 else if (length <= 1024)
794 l->stats.msg_length_profile[2]++;
795 else if (length <= 4096)
796 l->stats.msg_length_profile[3]++;
797 else if (length <= 16384)
798 l->stats.msg_length_profile[4]++;
799 else if (length <= 32768)
800 l->stats.msg_length_profile[5]++;
801 else
802 l->stats.msg_length_profile[6]++;
803}
804
805/**
806 * tipc_link_too_silent - check if link is "too silent"
807 * @l: tipc link to be checked
808 *
809 * Return: true if the link 'silent_intv_cnt' is about to reach the
810 * 'abort_limit' value, otherwise false
811 */
812bool tipc_link_too_silent(struct tipc_link *l)
813{
814 return (l->silent_intv_cnt + 2 > l->abort_limit);
815}
816
817/* tipc_link_timeout - perform periodic task as instructed from node timeout
818 */
819int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
820{
821 int mtyp = 0;
822 int rc = 0;
823 bool state = false;
824 bool probe = false;
825 bool setup = false;
826 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
827 u16 bc_acked = l->bc_rcvlink->acked;
828 struct tipc_mon_state *mstate = &l->mon_state;
829
830 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
831 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
832 switch (l->state) {
833 case LINK_ESTABLISHED:
834 case LINK_SYNCHING:
835 mtyp = STATE_MSG;
836 link_profile_stats(l);
837 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
838 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
839 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
840 state = bc_acked != bc_snt;
841 state |= l->bc_rcvlink->rcv_unacked;
842 state |= l->rcv_unacked;
843 state |= !skb_queue_empty(&l->transmq);
844 probe = mstate->probing;
845 probe |= l->silent_intv_cnt;
846 if (probe || mstate->monitoring)
847 l->silent_intv_cnt++;
848 probe |= !skb_queue_empty(&l->deferdq);
849 if (l->snd_nxt == l->checkpoint) {
850 tipc_link_update_cwin(l, 0, 0);
851 probe = true;
852 }
853 l->checkpoint = l->snd_nxt;
854 break;
855 case LINK_RESET:
856 setup = l->rst_cnt++ <= 4;
857 setup |= !(l->rst_cnt % 16);
858 mtyp = RESET_MSG;
859 break;
860 case LINK_ESTABLISHING:
861 setup = true;
862 mtyp = ACTIVATE_MSG;
863 break;
864 case LINK_PEER_RESET:
865 case LINK_RESETTING:
866 case LINK_FAILINGOVER:
867 break;
868 default:
869 break;
870 }
871
872 if (state || probe || setup)
873 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
874
875 return rc;
876}
877
878/**
879 * link_schedule_user - schedule a message sender for wakeup after congestion
880 * @l: congested link
881 * @hdr: header of message that is being sent
882 * Create pseudo msg to send back to user when congestion abates
883 */
884static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
885{
886 u32 dnode = tipc_own_addr(l->net);
887 u32 dport = msg_origport(hdr);
888 struct sk_buff *skb;
889
890 /* Create and schedule wakeup pseudo message */
891 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
892 dnode, l->addr, dport, 0, 0);
893 if (!skb)
894 return -ENOBUFS;
895 msg_set_dest_droppable(buf_msg(skb), true);
896 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
897 skb_queue_tail(&l->wakeupq, skb);
898 l->stats.link_congs++;
899 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
900 return -ELINKCONG;
901}
902
903/**
904 * link_prepare_wakeup - prepare users for wakeup after congestion
905 * @l: congested link
906 * Wake up a number of waiting users, as permitted by available space
907 * in the send queue
908 */
909static void link_prepare_wakeup(struct tipc_link *l)
910{
911 struct sk_buff_head *wakeupq = &l->wakeupq;
912 struct sk_buff_head *inputq = l->inputq;
913 struct sk_buff *skb, *tmp;
914 struct sk_buff_head tmpq;
915 int avail[5] = {0,};
916 int imp = 0;
917
918 __skb_queue_head_init(&tmpq);
919
920 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
921 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
922
923 skb_queue_walk_safe(wakeupq, skb, tmp) {
924 imp = TIPC_SKB_CB(skb)->chain_imp;
925 if (avail[imp] <= 0)
926 continue;
927 avail[imp]--;
928 __skb_unlink(skb, wakeupq);
929 __skb_queue_tail(&tmpq, skb);
930 }
931
932 spin_lock_bh(&inputq->lock);
933 skb_queue_splice_tail(&tmpq, inputq);
934 spin_unlock_bh(&inputq->lock);
935
936}
937
938/**
939 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
940 * the given skb should be next attempted
941 * @skb: skb to set a future retransmission time for
942 * @l: link the skb will be transmitted on
943 */
944static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
945 struct tipc_link *l)
946{
947 if (link_is_bc_sndlink(l))
948 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
949 else
950 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
951}
952
953void tipc_link_reset(struct tipc_link *l)
954{
955 struct sk_buff_head list;
956 u32 imp;
957
958 __skb_queue_head_init(&list);
959
960 l->in_session = false;
961 /* Force re-synch of peer session number before establishing */
962 l->peer_session--;
963 l->session++;
964 l->mtu = l->advertised_mtu;
965
966 spin_lock_bh(&l->wakeupq.lock);
967 skb_queue_splice_init(&l->wakeupq, &list);
968 spin_unlock_bh(&l->wakeupq.lock);
969
970 spin_lock_bh(&l->inputq->lock);
971 skb_queue_splice_init(&list, l->inputq);
972 spin_unlock_bh(&l->inputq->lock);
973
974 __skb_queue_purge(&l->transmq);
975 __skb_queue_purge(&l->deferdq);
976 __skb_queue_purge(&l->backlogq);
977 __skb_queue_purge(&l->failover_deferdq);
978 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
979 l->backlog[imp].len = 0;
980 l->backlog[imp].target_bskb = NULL;
981 }
982 kfree_skb(l->reasm_buf);
983 kfree_skb(l->reasm_tnlmsg);
984 kfree_skb(l->failover_reasm_skb);
985 l->reasm_buf = NULL;
986 l->reasm_tnlmsg = NULL;
987 l->failover_reasm_skb = NULL;
988 l->rcv_unacked = 0;
989 l->snd_nxt = 1;
990 l->rcv_nxt = 1;
991 l->snd_nxt_state = 1;
992 l->rcv_nxt_state = 1;
993 l->acked = 0;
994 l->last_gap = 0;
995 kfree(l->last_ga);
996 l->last_ga = NULL;
997 l->silent_intv_cnt = 0;
998 l->rst_cnt = 0;
999 l->bc_peer_is_up = false;
1000 memset(&l->mon_state, 0, sizeof(l->mon_state));
1001 tipc_link_reset_stats(l);
1002}
1003
1004/**
1005 * tipc_link_xmit(): enqueue buffer list according to queue situation
1006 * @l: link to use
1007 * @list: chain of buffers containing message
1008 * @xmitq: returned list of packets to be sent by caller
1009 *
1010 * Consumes the buffer chain.
1011 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1012 * Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
1013 */
1014int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1015 struct sk_buff_head *xmitq)
1016{
1017 struct sk_buff_head *backlogq = &l->backlogq;
1018 struct sk_buff_head *transmq = &l->transmq;
1019 struct sk_buff *skb, *_skb;
1020 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1021 u16 ack = l->rcv_nxt - 1;
1022 u16 seqno = l->snd_nxt;
1023 int pkt_cnt = skb_queue_len(list);
1024 unsigned int mss = tipc_link_mss(l);
1025 unsigned int cwin = l->window;
1026 unsigned int mtu = l->mtu;
1027 struct tipc_msg *hdr;
1028 bool new_bundle;
1029 int rc = 0;
1030 int imp;
1031
1032 if (pkt_cnt <= 0)
1033 return 0;
1034
1035 hdr = buf_msg(skb_peek(list));
1036 if (unlikely(msg_size(hdr) > mtu)) {
1037 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1038 skb_queue_len(list), msg_user(hdr),
1039 msg_type(hdr), msg_size(hdr), mtu);
1040 __skb_queue_purge(list);
1041 return -EMSGSIZE;
1042 }
1043
1044 imp = msg_importance(hdr);
1045 /* Allow oversubscription of one data msg per source at congestion */
1046 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1047 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1048 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1049 return -ENOBUFS;
1050 }
1051 rc = link_schedule_user(l, hdr);
1052 }
1053
1054 if (pkt_cnt > 1) {
1055 l->stats.sent_fragmented++;
1056 l->stats.sent_fragments += pkt_cnt;
1057 }
1058
1059 /* Prepare each packet for sending, and add to relevant queue: */
1060 while ((skb = __skb_dequeue(list))) {
1061 if (likely(skb_queue_len(transmq) < cwin)) {
1062 hdr = buf_msg(skb);
1063 msg_set_seqno(hdr, seqno);
1064 msg_set_ack(hdr, ack);
1065 msg_set_bcast_ack(hdr, bc_ack);
1066 _skb = skb_clone(skb, GFP_ATOMIC);
1067 if (!_skb) {
1068 kfree_skb(skb);
1069 __skb_queue_purge(list);
1070 return -ENOBUFS;
1071 }
1072 __skb_queue_tail(transmq, skb);
1073 tipc_link_set_skb_retransmit_time(skb, l);
1074 __skb_queue_tail(xmitq, _skb);
1075 TIPC_SKB_CB(skb)->ackers = l->ackers;
1076 l->rcv_unacked = 0;
1077 l->stats.sent_pkts++;
1078 seqno++;
1079 continue;
1080 }
1081 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1082 mss, l->addr, &new_bundle)) {
1083 if (skb) {
1084 /* Keep a ref. to the skb for next try */
1085 l->backlog[imp].target_bskb = skb;
1086 l->backlog[imp].len++;
1087 __skb_queue_tail(backlogq, skb);
1088 } else {
1089 if (new_bundle) {
1090 l->stats.sent_bundles++;
1091 l->stats.sent_bundled++;
1092 }
1093 l->stats.sent_bundled++;
1094 }
1095 continue;
1096 }
1097 l->backlog[imp].target_bskb = NULL;
1098 l->backlog[imp].len += (1 + skb_queue_len(list));
1099 __skb_queue_tail(backlogq, skb);
1100 skb_queue_splice_tail_init(list, backlogq);
1101 }
1102 l->snd_nxt = seqno;
1103 return rc;
1104}
1105
1106static void tipc_link_update_cwin(struct tipc_link *l, int released,
1107 bool retransmitted)
1108{
1109 int bklog_len = skb_queue_len(&l->backlogq);
1110 struct sk_buff_head *txq = &l->transmq;
1111 int txq_len = skb_queue_len(txq);
1112 u16 cwin = l->window;
1113
1114 /* Enter fast recovery */
1115 if (unlikely(retransmitted)) {
1116 l->ssthresh = max_t(u16, l->window / 2, 300);
1117 l->window = min_t(u16, l->ssthresh, l->window);
1118 return;
1119 }
1120 /* Enter slow start */
1121 if (unlikely(!released)) {
1122 l->ssthresh = max_t(u16, l->window / 2, 300);
1123 l->window = l->min_win;
1124 return;
1125 }
1126 /* Don't increase window if no pressure on the transmit queue */
1127 if (txq_len + bklog_len < cwin)
1128 return;
1129
1130 /* Don't increase window if there are holes the transmit queue */
1131 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1132 return;
1133
1134 l->cong_acks += released;
1135
1136 /* Slow start */
1137 if (cwin <= l->ssthresh) {
1138 l->window = min_t(u16, cwin + released, l->max_win);
1139 return;
1140 }
1141 /* Congestion avoidance */
1142 if (l->cong_acks < cwin)
1143 return;
1144 l->window = min_t(u16, ++cwin, l->max_win);
1145 l->cong_acks = 0;
1146}
1147
1148static void tipc_link_advance_backlog(struct tipc_link *l,
1149 struct sk_buff_head *xmitq)
1150{
1151 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1152 struct sk_buff_head *txq = &l->transmq;
1153 struct sk_buff *skb, *_skb;
1154 u16 ack = l->rcv_nxt - 1;
1155 u16 seqno = l->snd_nxt;
1156 struct tipc_msg *hdr;
1157 u16 cwin = l->window;
1158 u32 imp;
1159
1160 while (skb_queue_len(txq) < cwin) {
1161 skb = skb_peek(&l->backlogq);
1162 if (!skb)
1163 break;
1164 _skb = skb_clone(skb, GFP_ATOMIC);
1165 if (!_skb)
1166 break;
1167 __skb_dequeue(&l->backlogq);
1168 hdr = buf_msg(skb);
1169 imp = msg_importance(hdr);
1170 l->backlog[imp].len--;
1171 if (unlikely(skb == l->backlog[imp].target_bskb))
1172 l->backlog[imp].target_bskb = NULL;
1173 __skb_queue_tail(&l->transmq, skb);
1174 tipc_link_set_skb_retransmit_time(skb, l);
1175
1176 __skb_queue_tail(xmitq, _skb);
1177 TIPC_SKB_CB(skb)->ackers = l->ackers;
1178 msg_set_seqno(hdr, seqno);
1179 msg_set_ack(hdr, ack);
1180 msg_set_bcast_ack(hdr, bc_ack);
1181 l->rcv_unacked = 0;
1182 l->stats.sent_pkts++;
1183 seqno++;
1184 }
1185 l->snd_nxt = seqno;
1186}
1187
1188/**
1189 * link_retransmit_failure() - Detect repeated retransmit failures
1190 * @l: tipc link sender
1191 * @r: tipc link receiver (= l in case of unicast)
1192 * @rc: returned code
1193 *
1194 * Return: true if the repeated retransmit failures happens, otherwise
1195 * false
1196 */
1197static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1198 int *rc)
1199{
1200 struct sk_buff *skb = skb_peek(&l->transmq);
1201 struct tipc_msg *hdr;
1202
1203 if (!skb)
1204 return false;
1205
1206 if (!TIPC_SKB_CB(skb)->retr_cnt)
1207 return false;
1208
1209 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1210 msecs_to_jiffies(r->tolerance * 10)))
1211 return false;
1212
1213 hdr = buf_msg(skb);
1214 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1215 return false;
1216
1217 pr_warn("Retransmission failure on link <%s>\n", l->name);
1218 link_print(l, "State of link ");
1219 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1220 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1221 pr_info("sqno %u, prev: %x, dest: %x\n",
1222 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1223 pr_info("retr_stamp %d, retr_cnt %d\n",
1224 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1225 TIPC_SKB_CB(skb)->retr_cnt);
1226
1227 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1228 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1229 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1230
1231 if (link_is_bc_sndlink(l)) {
1232 r->state = LINK_RESET;
1233 *rc |= TIPC_LINK_DOWN_EVT;
1234 } else {
1235 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1236 }
1237
1238 return true;
1239}
1240
1241/* tipc_data_input - deliver data and name distr msgs to upper layer
1242 *
1243 * Consumes buffer if message is of right type
1244 * Node lock must be held
1245 */
1246static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1247 struct sk_buff_head *inputq)
1248{
1249 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1250 struct tipc_msg *hdr = buf_msg(skb);
1251
1252 switch (msg_user(hdr)) {
1253 case TIPC_LOW_IMPORTANCE:
1254 case TIPC_MEDIUM_IMPORTANCE:
1255 case TIPC_HIGH_IMPORTANCE:
1256 case TIPC_CRITICAL_IMPORTANCE:
1257 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1258 skb_queue_tail(mc_inputq, skb);
1259 return true;
1260 }
1261 fallthrough;
1262 case CONN_MANAGER:
1263 skb_queue_tail(inputq, skb);
1264 return true;
1265 case GROUP_PROTOCOL:
1266 skb_queue_tail(mc_inputq, skb);
1267 return true;
1268 case NAME_DISTRIBUTOR:
1269 l->bc_rcvlink->state = LINK_ESTABLISHED;
1270 skb_queue_tail(l->namedq, skb);
1271 return true;
1272 case MSG_BUNDLER:
1273 case TUNNEL_PROTOCOL:
1274 case MSG_FRAGMENTER:
1275 case BCAST_PROTOCOL:
1276 return false;
1277#ifdef CONFIG_TIPC_CRYPTO
1278 case MSG_CRYPTO:
1279 if (sysctl_tipc_key_exchange_enabled &&
1280 TIPC_SKB_CB(skb)->decrypted) {
1281 tipc_crypto_msg_rcv(l->net, skb);
1282 return true;
1283 }
1284 fallthrough;
1285#endif
1286 default:
1287 pr_warn("Dropping received illegal msg type\n");
1288 kfree_skb(skb);
1289 return true;
1290 }
1291}
1292
1293/* tipc_link_input - process packet that has passed link protocol check
1294 *
1295 * Consumes buffer
1296 */
1297static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1298 struct sk_buff_head *inputq,
1299 struct sk_buff **reasm_skb)
1300{
1301 struct tipc_msg *hdr = buf_msg(skb);
1302 struct sk_buff *iskb;
1303 struct sk_buff_head tmpq;
1304 int usr = msg_user(hdr);
1305 int pos = 0;
1306
1307 if (usr == MSG_BUNDLER) {
1308 skb_queue_head_init(&tmpq);
1309 l->stats.recv_bundles++;
1310 l->stats.recv_bundled += msg_msgcnt(hdr);
1311 while (tipc_msg_extract(skb, &iskb, &pos))
1312 tipc_data_input(l, iskb, &tmpq);
1313 tipc_skb_queue_splice_tail(&tmpq, inputq);
1314 return 0;
1315 } else if (usr == MSG_FRAGMENTER) {
1316 l->stats.recv_fragments++;
1317 if (tipc_buf_append(reasm_skb, &skb)) {
1318 l->stats.recv_fragmented++;
1319 tipc_data_input(l, skb, inputq);
1320 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1321 pr_warn_ratelimited("Unable to build fragment list\n");
1322 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1323 }
1324 return 0;
1325 } else if (usr == BCAST_PROTOCOL) {
1326 tipc_bcast_lock(l->net);
1327 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1328 tipc_bcast_unlock(l->net);
1329 }
1330
1331 kfree_skb(skb);
1332 return 0;
1333}
1334
1335/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1336 * inner message along with the ones in the old link's
1337 * deferdq
1338 * @l: tunnel link
1339 * @skb: TUNNEL_PROTOCOL message
1340 * @inputq: queue to put messages ready for delivery
1341 */
1342static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1343 struct sk_buff_head *inputq)
1344{
1345 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1346 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1347 struct sk_buff_head *fdefq = &l->failover_deferdq;
1348 struct tipc_msg *hdr = buf_msg(skb);
1349 struct sk_buff *iskb;
1350 int ipos = 0;
1351 int rc = 0;
1352 u16 seqno;
1353
1354 if (msg_type(hdr) == SYNCH_MSG) {
1355 kfree_skb(skb);
1356 return 0;
1357 }
1358
1359 /* Not a fragment? */
1360 if (likely(!msg_nof_fragms(hdr))) {
1361 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1362 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1363 skb_queue_len(fdefq));
1364 return 0;
1365 }
1366 kfree_skb(skb);
1367 } else {
1368 /* Set fragment type for buf_append */
1369 if (msg_fragm_no(hdr) == 1)
1370 msg_set_type(hdr, FIRST_FRAGMENT);
1371 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1372 msg_set_type(hdr, FRAGMENT);
1373 else
1374 msg_set_type(hdr, LAST_FRAGMENT);
1375
1376 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1377 /* Successful but non-complete reassembly? */
1378 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1379 return 0;
1380 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1381 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1382 }
1383 iskb = skb;
1384 }
1385
1386 do {
1387 seqno = buf_seqno(iskb);
1388 if (unlikely(less(seqno, l->drop_point))) {
1389 kfree_skb(iskb);
1390 continue;
1391 }
1392 if (unlikely(seqno != l->drop_point)) {
1393 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1394 continue;
1395 }
1396
1397 l->drop_point++;
1398 if (!tipc_data_input(l, iskb, inputq))
1399 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1400 if (unlikely(rc))
1401 break;
1402 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1403
1404 return rc;
1405}
1406
1407/**
1408 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1409 * @ga: returned pointer to the Gap ACK blocks if any
1410 * @l: the tipc link
1411 * @hdr: the PROTOCOL/STATE_MSG header
1412 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1413 *
1414 * Return: the total Gap ACK blocks size
1415 */
1416u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1417 struct tipc_msg *hdr, bool uc)
1418{
1419 struct tipc_gap_ack_blks *p;
1420 u16 sz = 0;
1421
1422 /* Does peer support the Gap ACK blocks feature? */
1423 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1424 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1425 sz = ntohs(p->len);
1426 /* Sanity check */
1427 if (sz == struct_size(p, gacks, size_add(p->ugack_cnt, p->bgack_cnt))) {
1428 /* Good, check if the desired type exists */
1429 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1430 goto ok;
1431 /* Backward compatible: peer might not support bc, but uc? */
1432 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1433 if (p->ugack_cnt) {
1434 p->bgack_cnt = 0;
1435 goto ok;
1436 }
1437 }
1438 }
1439 /* Other cases: ignore! */
1440 p = NULL;
1441
1442ok:
1443 *ga = p;
1444 return sz;
1445}
1446
1447static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1448 struct tipc_link *l, u8 start_index)
1449{
1450 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1451 struct sk_buff *skb = skb_peek(&l->deferdq);
1452 u16 expect, seqno = 0;
1453 u8 n = 0;
1454
1455 if (!skb)
1456 return 0;
1457
1458 expect = buf_seqno(skb);
1459 skb_queue_walk(&l->deferdq, skb) {
1460 seqno = buf_seqno(skb);
1461 if (unlikely(more(seqno, expect))) {
1462 gacks[n].ack = htons(expect - 1);
1463 gacks[n].gap = htons(seqno - expect);
1464 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1465 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1466 l->name, n,
1467 skb_queue_len(&l->deferdq));
1468 return n;
1469 }
1470 } else if (unlikely(less(seqno, expect))) {
1471 pr_warn("Unexpected skb in deferdq!\n");
1472 continue;
1473 }
1474 expect = seqno + 1;
1475 }
1476
1477 /* last block */
1478 gacks[n].ack = htons(seqno);
1479 gacks[n].gap = 0;
1480 n++;
1481 return n;
1482}
1483
1484/* tipc_build_gap_ack_blks - build Gap ACK blocks
1485 * @l: tipc unicast link
1486 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1487 *
1488 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1489 * links of a certain peer, the buffer after built has the network data format
1490 * as found at the struct tipc_gap_ack_blks definition.
1491 *
1492 * returns the actual allocated memory size
1493 */
1494static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1495{
1496 struct tipc_link *bcl = l->bc_rcvlink;
1497 struct tipc_gap_ack_blks *ga;
1498 u16 len;
1499
1500 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1501
1502 /* Start with broadcast link first */
1503 tipc_bcast_lock(bcl->net);
1504 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1505 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1506 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1507 tipc_bcast_unlock(bcl->net);
1508
1509 /* Now for unicast link, but an explicit NACK only (???) */
1510 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1511 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1512
1513 /* Total len */
1514 len = struct_size(ga, gacks, size_add(ga->bgack_cnt, ga->ugack_cnt));
1515 ga->len = htons(len);
1516 return len;
1517}
1518
1519/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1520 * acked packets, also doing retransmissions if
1521 * gaps found
1522 * @l: tipc link with transmq queue to be advanced
1523 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1524 * @acked: seqno of last packet acked by peer without any gaps before
1525 * @gap: # of gap packets
1526 * @ga: buffer pointer to Gap ACK blocks from peer
1527 * @xmitq: queue for accumulating the retransmitted packets if any
1528 * @retransmitted: returned boolean value if a retransmission is really issued
1529 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1530 * happens (- unlikely case)
1531 *
1532 * Return: the number of packets released from the link transmq
1533 */
1534static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1535 u16 acked, u16 gap,
1536 struct tipc_gap_ack_blks *ga,
1537 struct sk_buff_head *xmitq,
1538 bool *retransmitted, int *rc)
1539{
1540 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1541 struct tipc_gap_ack *gacks = NULL;
1542 struct sk_buff *skb, *_skb, *tmp;
1543 struct tipc_msg *hdr;
1544 u32 qlen = skb_queue_len(&l->transmq);
1545 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1546 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1547 u16 ack = l->rcv_nxt - 1;
1548 u16 seqno, n = 0;
1549 u16 end = r->acked, start = end, offset = r->last_gap;
1550 u16 si = (last_ga) ? last_ga->start_index : 0;
1551 bool is_uc = !link_is_bc_sndlink(l);
1552 bool bc_has_acked = false;
1553
1554 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1555
1556 /* Determine Gap ACK blocks if any for the particular link */
1557 if (ga && is_uc) {
1558 /* Get the Gap ACKs, uc part */
1559 gack_cnt = ga->ugack_cnt;
1560 gacks = &ga->gacks[ga->bgack_cnt];
1561 } else if (ga) {
1562 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1563 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1564 GFP_ATOMIC);
1565 if (likely(this_ga)) {
1566 this_ga->start_index = 0;
1567 /* Start with the bc Gap ACKs */
1568 gack_cnt = this_ga->bgack_cnt;
1569 gacks = &this_ga->gacks[0];
1570 } else {
1571 /* Hmm, we can get in trouble..., simply ignore it */
1572 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1573 }
1574 }
1575
1576 /* Advance the link transmq */
1577 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1578 seqno = buf_seqno(skb);
1579
1580next_gap_ack:
1581 if (less_eq(seqno, nacked)) {
1582 if (is_uc)
1583 goto release;
1584 /* Skip packets peer has already acked */
1585 if (!more(seqno, r->acked))
1586 continue;
1587 /* Get the next of last Gap ACK blocks */
1588 while (more(seqno, end)) {
1589 if (!last_ga || si >= last_ga->bgack_cnt)
1590 break;
1591 start = end + offset + 1;
1592 end = ntohs(last_ga->gacks[si].ack);
1593 offset = ntohs(last_ga->gacks[si].gap);
1594 si++;
1595 WARN_ONCE(more(start, end) ||
1596 (!offset &&
1597 si < last_ga->bgack_cnt) ||
1598 si > MAX_GAP_ACK_BLKS,
1599 "Corrupted Gap ACK: %d %d %d %d %d\n",
1600 start, end, offset, si,
1601 last_ga->bgack_cnt);
1602 }
1603 /* Check against the last Gap ACK block */
1604 if (tipc_in_range(seqno, start, end))
1605 continue;
1606 /* Update/release the packet peer is acking */
1607 bc_has_acked = true;
1608 if (--TIPC_SKB_CB(skb)->ackers)
1609 continue;
1610release:
1611 /* release skb */
1612 __skb_unlink(skb, &l->transmq);
1613 kfree_skb(skb);
1614 } else if (less_eq(seqno, nacked + ngap)) {
1615 /* First gap: check if repeated retrans failures? */
1616 if (unlikely(seqno == acked + 1 &&
1617 link_retransmit_failure(l, r, rc))) {
1618 /* Ignore this bc Gap ACKs if any */
1619 kfree(this_ga);
1620 this_ga = NULL;
1621 break;
1622 }
1623 /* retransmit skb if unrestricted*/
1624 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1625 continue;
1626 tipc_link_set_skb_retransmit_time(skb, l);
1627 _skb = pskb_copy(skb, GFP_ATOMIC);
1628 if (!_skb)
1629 continue;
1630 hdr = buf_msg(_skb);
1631 msg_set_ack(hdr, ack);
1632 msg_set_bcast_ack(hdr, bc_ack);
1633 _skb->priority = TC_PRIO_CONTROL;
1634 __skb_queue_tail(xmitq, _skb);
1635 l->stats.retransmitted++;
1636 if (!is_uc)
1637 r->stats.retransmitted++;
1638 *retransmitted = true;
1639 /* Increase actual retrans counter & mark first time */
1640 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1641 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1642 } else {
1643 /* retry with Gap ACK blocks if any */
1644 if (n >= gack_cnt)
1645 break;
1646 nacked = ntohs(gacks[n].ack);
1647 ngap = ntohs(gacks[n].gap);
1648 n++;
1649 goto next_gap_ack;
1650 }
1651 }
1652
1653 /* Renew last Gap ACK blocks for bc if needed */
1654 if (bc_has_acked) {
1655 if (this_ga) {
1656 kfree(last_ga);
1657 r->last_ga = this_ga;
1658 r->last_gap = gap;
1659 } else if (last_ga) {
1660 if (less(acked, start)) {
1661 si--;
1662 offset = start - acked - 1;
1663 } else if (less(acked, end)) {
1664 acked = end;
1665 }
1666 if (si < last_ga->bgack_cnt) {
1667 last_ga->start_index = si;
1668 r->last_gap = offset;
1669 } else {
1670 kfree(last_ga);
1671 r->last_ga = NULL;
1672 r->last_gap = 0;
1673 }
1674 } else {
1675 r->last_gap = 0;
1676 }
1677 r->acked = acked;
1678 } else {
1679 kfree(this_ga);
1680 }
1681
1682 return qlen - skb_queue_len(&l->transmq);
1683}
1684
1685/* tipc_link_build_state_msg: prepare link state message for transmission
1686 *
1687 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1688 * risk of ack storms towards the sender
1689 */
1690int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1691{
1692 if (!l)
1693 return 0;
1694
1695 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1696 if (link_is_bc_rcvlink(l)) {
1697 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1698 return 0;
1699 l->rcv_unacked = 0;
1700
1701 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1702 l->snd_nxt = l->rcv_nxt;
1703 return TIPC_LINK_SND_STATE;
1704 }
1705 /* Unicast ACK */
1706 l->rcv_unacked = 0;
1707 l->stats.sent_acks++;
1708 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1709 return 0;
1710}
1711
1712/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1713 */
1714void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1715{
1716 int mtyp = RESET_MSG;
1717 struct sk_buff *skb;
1718
1719 if (l->state == LINK_ESTABLISHING)
1720 mtyp = ACTIVATE_MSG;
1721
1722 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1723
1724 /* Inform peer that this endpoint is going down if applicable */
1725 skb = skb_peek_tail(xmitq);
1726 if (skb && (l->state == LINK_RESET))
1727 msg_set_peer_stopping(buf_msg(skb), 1);
1728}
1729
1730/* tipc_link_build_nack_msg: prepare link nack message for transmission
1731 * Note that sending of broadcast NACK is coordinated among nodes, to
1732 * reduce the risk of NACK storms towards the sender
1733 */
1734static int tipc_link_build_nack_msg(struct tipc_link *l,
1735 struct sk_buff_head *xmitq)
1736{
1737 u32 def_cnt = ++l->stats.deferred_recv;
1738 struct sk_buff_head *dfq = &l->deferdq;
1739 u32 defq_len = skb_queue_len(dfq);
1740 int match1, match2;
1741
1742 if (link_is_bc_rcvlink(l)) {
1743 match1 = def_cnt & 0xf;
1744 match2 = tipc_own_addr(l->net) & 0xf;
1745 if (match1 == match2)
1746 return TIPC_LINK_SND_STATE;
1747 return 0;
1748 }
1749
1750 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1751 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1752
1753 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1754 rcvgap, 0, 0, xmitq);
1755 }
1756 return 0;
1757}
1758
1759/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1760 * @l: the link that should handle the message
1761 * @skb: TIPC packet
1762 * @xmitq: queue to place packets to be sent after this call
1763 */
1764int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1765 struct sk_buff_head *xmitq)
1766{
1767 struct sk_buff_head *defq = &l->deferdq;
1768 struct tipc_msg *hdr = buf_msg(skb);
1769 u16 seqno, rcv_nxt, win_lim;
1770 int released = 0;
1771 int rc = 0;
1772
1773 /* Verify and update link state */
1774 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1775 return tipc_link_proto_rcv(l, skb, xmitq);
1776
1777 /* Don't send probe at next timeout expiration */
1778 l->silent_intv_cnt = 0;
1779
1780 do {
1781 hdr = buf_msg(skb);
1782 seqno = msg_seqno(hdr);
1783 rcv_nxt = l->rcv_nxt;
1784 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1785
1786 if (unlikely(!tipc_link_is_up(l))) {
1787 if (l->state == LINK_ESTABLISHING)
1788 rc = TIPC_LINK_UP_EVT;
1789 kfree_skb(skb);
1790 break;
1791 }
1792
1793 /* Drop if outside receive window */
1794 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1795 l->stats.duplicates++;
1796 kfree_skb(skb);
1797 break;
1798 }
1799 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1800 NULL, NULL, NULL, NULL);
1801
1802 /* Defer delivery if sequence gap */
1803 if (unlikely(seqno != rcv_nxt)) {
1804 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1805 l->stats.duplicates++;
1806 rc |= tipc_link_build_nack_msg(l, xmitq);
1807 break;
1808 }
1809
1810 /* Deliver packet */
1811 l->rcv_nxt++;
1812 l->stats.recv_pkts++;
1813
1814 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1815 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1816 else if (!tipc_data_input(l, skb, l->inputq))
1817 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1818 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1819 rc |= tipc_link_build_state_msg(l, xmitq);
1820 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1821 break;
1822 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1823
1824 /* Forward queues and wake up waiting users */
1825 if (released) {
1826 tipc_link_update_cwin(l, released, 0);
1827 tipc_link_advance_backlog(l, xmitq);
1828 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1829 link_prepare_wakeup(l);
1830 }
1831 return rc;
1832}
1833
1834static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1835 bool probe_reply, u16 rcvgap,
1836 int tolerance, int priority,
1837 struct sk_buff_head *xmitq)
1838{
1839 struct tipc_mon_state *mstate = &l->mon_state;
1840 struct sk_buff_head *dfq = &l->deferdq;
1841 struct tipc_link *bcl = l->bc_rcvlink;
1842 struct tipc_msg *hdr;
1843 struct sk_buff *skb;
1844 bool node_up = tipc_link_is_up(bcl);
1845 u16 glen = 0, bc_rcvgap = 0;
1846 int dlen = 0;
1847 void *data;
1848
1849 /* Don't send protocol message during reset or link failover */
1850 if (tipc_link_is_blocked(l))
1851 return;
1852
1853 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1854 return;
1855
1856 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1857 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1858
1859 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1860 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1861 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1862 if (!skb)
1863 return;
1864
1865 hdr = buf_msg(skb);
1866 data = msg_data(hdr);
1867 msg_set_session(hdr, l->session);
1868 msg_set_bearer_id(hdr, l->bearer_id);
1869 msg_set_net_plane(hdr, l->net_plane);
1870 msg_set_next_sent(hdr, l->snd_nxt);
1871 msg_set_ack(hdr, l->rcv_nxt - 1);
1872 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1873 msg_set_bc_ack_invalid(hdr, !node_up);
1874 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1875 msg_set_link_tolerance(hdr, tolerance);
1876 msg_set_linkprio(hdr, priority);
1877 msg_set_redundant_link(hdr, node_up);
1878 msg_set_seq_gap(hdr, 0);
1879 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1880
1881 if (mtyp == STATE_MSG) {
1882 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1883 msg_set_seqno(hdr, l->snd_nxt_state++);
1884 msg_set_seq_gap(hdr, rcvgap);
1885 bc_rcvgap = link_bc_rcv_gap(bcl);
1886 msg_set_bc_gap(hdr, bc_rcvgap);
1887 msg_set_probe(hdr, probe);
1888 msg_set_is_keepalive(hdr, probe || probe_reply);
1889 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1890 glen = tipc_build_gap_ack_blks(l, hdr);
1891 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1892 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1893 skb_trim(skb, INT_H_SIZE + glen + dlen);
1894 l->stats.sent_states++;
1895 l->rcv_unacked = 0;
1896 } else {
1897 /* RESET_MSG or ACTIVATE_MSG */
1898 if (mtyp == ACTIVATE_MSG) {
1899 msg_set_dest_session_valid(hdr, 1);
1900 msg_set_dest_session(hdr, l->peer_session);
1901 }
1902 msg_set_max_pkt(hdr, l->advertised_mtu);
1903 strcpy(data, l->if_name);
1904 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1905 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1906 }
1907 if (probe)
1908 l->stats.sent_probes++;
1909 if (rcvgap)
1910 l->stats.sent_nacks++;
1911 if (bc_rcvgap)
1912 bcl->stats.sent_nacks++;
1913 skb->priority = TC_PRIO_CONTROL;
1914 __skb_queue_tail(xmitq, skb);
1915 trace_tipc_proto_build(skb, false, l->name);
1916}
1917
1918void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1919 struct sk_buff_head *xmitq)
1920{
1921 u32 onode = tipc_own_addr(l->net);
1922 struct tipc_msg *hdr, *ihdr;
1923 struct sk_buff_head tnlq;
1924 struct sk_buff *skb;
1925 u32 dnode = l->addr;
1926
1927 __skb_queue_head_init(&tnlq);
1928 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1929 INT_H_SIZE, BASIC_H_SIZE,
1930 dnode, onode, 0, 0, 0);
1931 if (!skb) {
1932 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1933 return;
1934 }
1935
1936 hdr = buf_msg(skb);
1937 msg_set_msgcnt(hdr, 1);
1938 msg_set_bearer_id(hdr, l->peer_bearer_id);
1939
1940 ihdr = (struct tipc_msg *)msg_data(hdr);
1941 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1942 BASIC_H_SIZE, dnode);
1943 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1944 __skb_queue_tail(&tnlq, skb);
1945 tipc_link_xmit(l, &tnlq, xmitq);
1946}
1947
1948/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1949 * with contents of the link's transmit and backlog queues.
1950 */
1951void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1952 int mtyp, struct sk_buff_head *xmitq)
1953{
1954 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1955 struct sk_buff *skb, *tnlskb;
1956 struct tipc_msg *hdr, tnlhdr;
1957 struct sk_buff_head *queue = &l->transmq;
1958 struct sk_buff_head tmpxq, tnlq, frags;
1959 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1960 bool pktcnt_need_update = false;
1961 u16 syncpt;
1962 int rc;
1963
1964 if (!tnl)
1965 return;
1966
1967 __skb_queue_head_init(&tnlq);
1968 /* Link Synching:
1969 * From now on, send only one single ("dummy") SYNCH message
1970 * to peer. The SYNCH message does not contain any data, just
1971 * a header conveying the synch point to the peer.
1972 */
1973 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1974 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1975 INT_H_SIZE, 0, l->addr,
1976 tipc_own_addr(l->net),
1977 0, 0, 0);
1978 if (!tnlskb) {
1979 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1980 link_co_err);
1981 return;
1982 }
1983
1984 hdr = buf_msg(tnlskb);
1985 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1986 msg_set_syncpt(hdr, syncpt);
1987 msg_set_bearer_id(hdr, l->peer_bearer_id);
1988 __skb_queue_tail(&tnlq, tnlskb);
1989 tipc_link_xmit(tnl, &tnlq, xmitq);
1990 return;
1991 }
1992
1993 __skb_queue_head_init(&tmpxq);
1994 __skb_queue_head_init(&frags);
1995 /* At least one packet required for safe algorithm => add dummy */
1996 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1997 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1998 0, 0, TIPC_ERR_NO_PORT);
1999 if (!skb) {
2000 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2001 return;
2002 }
2003 __skb_queue_tail(&tnlq, skb);
2004 tipc_link_xmit(l, &tnlq, &tmpxq);
2005 __skb_queue_purge(&tmpxq);
2006
2007 /* Initialize reusable tunnel packet header */
2008 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2009 mtyp, INT_H_SIZE, l->addr);
2010 if (mtyp == SYNCH_MSG)
2011 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2012 else
2013 pktcnt = skb_queue_len(&l->transmq);
2014 pktcnt += skb_queue_len(&l->backlogq);
2015 msg_set_msgcnt(&tnlhdr, pktcnt);
2016 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2017tnl:
2018 /* Wrap each packet into a tunnel packet */
2019 skb_queue_walk(queue, skb) {
2020 hdr = buf_msg(skb);
2021 if (queue == &l->backlogq)
2022 msg_set_seqno(hdr, seqno++);
2023 pktlen = msg_size(hdr);
2024
2025 /* Tunnel link MTU is not large enough? This could be
2026 * due to:
2027 * 1) Link MTU has just changed or set differently;
2028 * 2) Or FAILOVER on the top of a SYNCH message
2029 *
2030 * The 2nd case should not happen if peer supports
2031 * TIPC_TUNNEL_ENHANCED
2032 */
2033 if (pktlen > tnl->mtu - INT_H_SIZE) {
2034 if (mtyp == FAILOVER_MSG &&
2035 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2036 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2037 &frags);
2038 if (rc) {
2039 pr_warn("%sunable to frag msg: rc %d\n",
2040 link_co_err, rc);
2041 return;
2042 }
2043 pktcnt += skb_queue_len(&frags) - 1;
2044 pktcnt_need_update = true;
2045 skb_queue_splice_tail_init(&frags, &tnlq);
2046 continue;
2047 }
2048 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2049 * => Just warn it and return!
2050 */
2051 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2052 link_co_err, msg_user(hdr),
2053 msg_type(hdr), msg_size(hdr));
2054 return;
2055 }
2056
2057 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2058 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2059 if (!tnlskb) {
2060 pr_warn("%sunable to send packet\n", link_co_err);
2061 return;
2062 }
2063 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2064 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2065 __skb_queue_tail(&tnlq, tnlskb);
2066 }
2067 if (queue != &l->backlogq) {
2068 queue = &l->backlogq;
2069 goto tnl;
2070 }
2071
2072 if (pktcnt_need_update)
2073 skb_queue_walk(&tnlq, skb) {
2074 hdr = buf_msg(skb);
2075 msg_set_msgcnt(hdr, pktcnt);
2076 }
2077
2078 tipc_link_xmit(tnl, &tnlq, xmitq);
2079
2080 if (mtyp == FAILOVER_MSG) {
2081 tnl->drop_point = l->rcv_nxt;
2082 tnl->failover_reasm_skb = l->reasm_buf;
2083 l->reasm_buf = NULL;
2084
2085 /* Failover the link's deferdq */
2086 if (unlikely(!skb_queue_empty(fdefq))) {
2087 pr_warn("Link failover deferdq not empty: %d!\n",
2088 skb_queue_len(fdefq));
2089 __skb_queue_purge(fdefq);
2090 }
2091 skb_queue_splice_init(&l->deferdq, fdefq);
2092 }
2093}
2094
2095/**
2096 * tipc_link_failover_prepare() - prepare tnl for link failover
2097 *
2098 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2099 * see the tipc_node_link_failover() for details
2100 *
2101 * @l: failover link
2102 * @tnl: tunnel link
2103 * @xmitq: queue for messages to be xmited
2104 */
2105void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2106 struct sk_buff_head *xmitq)
2107{
2108 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2109
2110 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2111
2112 /* This failover link endpoint was never established before,
2113 * so it has not received anything from peer.
2114 * Otherwise, it must be a normal failover situation or the
2115 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2116 * would have to start over from scratch instead.
2117 */
2118 tnl->drop_point = 1;
2119 tnl->failover_reasm_skb = NULL;
2120
2121 /* Initiate the link's failover deferdq */
2122 if (unlikely(!skb_queue_empty(fdefq))) {
2123 pr_warn("Link failover deferdq not empty: %d!\n",
2124 skb_queue_len(fdefq));
2125 __skb_queue_purge(fdefq);
2126 }
2127}
2128
2129/* tipc_link_validate_msg(): validate message against current link state
2130 * Returns true if message should be accepted, otherwise false
2131 */
2132bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2133{
2134 u16 curr_session = l->peer_session;
2135 u16 session = msg_session(hdr);
2136 int mtyp = msg_type(hdr);
2137
2138 if (msg_user(hdr) != LINK_PROTOCOL)
2139 return true;
2140
2141 switch (mtyp) {
2142 case RESET_MSG:
2143 if (!l->in_session)
2144 return true;
2145 /* Accept only RESET with new session number */
2146 return more(session, curr_session);
2147 case ACTIVATE_MSG:
2148 if (!l->in_session)
2149 return true;
2150 /* Accept only ACTIVATE with new or current session number */
2151 return !less(session, curr_session);
2152 case STATE_MSG:
2153 /* Accept only STATE with current session number */
2154 if (!l->in_session)
2155 return false;
2156 if (session != curr_session)
2157 return false;
2158 /* Extra sanity check */
2159 if (!tipc_link_is_up(l) && msg_ack(hdr))
2160 return false;
2161 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2162 return true;
2163 /* Accept only STATE with new sequence number */
2164 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2165 default:
2166 return false;
2167 }
2168}
2169
2170/* tipc_link_proto_rcv(): receive link level protocol message :
2171 * Note that network plane id propagates through the network, and may
2172 * change at any time. The node with lowest numerical id determines
2173 * network plane
2174 */
2175static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2176 struct sk_buff_head *xmitq)
2177{
2178 struct tipc_msg *hdr = buf_msg(skb);
2179 struct tipc_gap_ack_blks *ga = NULL;
2180 bool reply = msg_probe(hdr), retransmitted = false;
2181 u32 dlen = msg_data_sz(hdr), glen = 0, msg_max;
2182 u16 peers_snd_nxt = msg_next_sent(hdr);
2183 u16 peers_tol = msg_link_tolerance(hdr);
2184 u16 peers_prio = msg_linkprio(hdr);
2185 u16 gap = msg_seq_gap(hdr);
2186 u16 ack = msg_ack(hdr);
2187 u16 rcv_nxt = l->rcv_nxt;
2188 u16 rcvgap = 0;
2189 int mtyp = msg_type(hdr);
2190 int rc = 0, released;
2191 char *if_name;
2192 void *data;
2193
2194 trace_tipc_proto_rcv(skb, false, l->name);
2195
2196 if (dlen > U16_MAX)
2197 goto exit;
2198
2199 if (tipc_link_is_blocked(l) || !xmitq)
2200 goto exit;
2201
2202 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2203 l->net_plane = msg_net_plane(hdr);
2204
2205 if (skb_linearize(skb))
2206 goto exit;
2207
2208 hdr = buf_msg(skb);
2209 data = msg_data(hdr);
2210
2211 if (!tipc_link_validate_msg(l, hdr)) {
2212 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2213 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2214 goto exit;
2215 }
2216
2217 switch (mtyp) {
2218 case RESET_MSG:
2219 case ACTIVATE_MSG:
2220 msg_max = msg_max_pkt(hdr);
2221 if (msg_max < tipc_bearer_min_mtu(l->net, l->bearer_id))
2222 break;
2223 /* Complete own link name with peer's interface name */
2224 if_name = strrchr(l->name, ':') + 1;
2225 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2226 break;
2227 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2228 break;
2229 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2230
2231 /* Update own tolerance if peer indicates a non-zero value */
2232 if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2233 l->tolerance = peers_tol;
2234 l->bc_rcvlink->tolerance = peers_tol;
2235 }
2236 /* Update own priority if peer's priority is higher */
2237 if (tipc_in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2238 l->priority = peers_prio;
2239
2240 /* If peer is going down we want full re-establish cycle */
2241 if (msg_peer_stopping(hdr)) {
2242 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2243 break;
2244 }
2245
2246 /* If this endpoint was re-created while peer was ESTABLISHING
2247 * it doesn't know current session number. Force re-synch.
2248 */
2249 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2250 l->session != msg_dest_session(hdr)) {
2251 if (less(l->session, msg_dest_session(hdr)))
2252 l->session = msg_dest_session(hdr) + 1;
2253 break;
2254 }
2255
2256 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2257 if (mtyp == RESET_MSG || !tipc_link_is_up(l))
2258 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2259
2260 /* ACTIVATE_MSG takes up link if it was already locally reset */
2261 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2262 rc = TIPC_LINK_UP_EVT;
2263
2264 l->peer_session = msg_session(hdr);
2265 l->in_session = true;
2266 l->peer_bearer_id = msg_bearer_id(hdr);
2267 if (l->mtu > msg_max)
2268 l->mtu = msg_max;
2269 break;
2270
2271 case STATE_MSG:
2272 /* Validate Gap ACK blocks, drop if invalid */
2273 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2274 if (glen > dlen)
2275 break;
2276
2277 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2278
2279 /* Update own tolerance if peer indicates a non-zero value */
2280 if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2281 l->tolerance = peers_tol;
2282 l->bc_rcvlink->tolerance = peers_tol;
2283 }
2284 /* Update own prio if peer indicates a different value */
2285 if ((peers_prio != l->priority) &&
2286 tipc_in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2287 l->priority = peers_prio;
2288 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2289 }
2290
2291 l->silent_intv_cnt = 0;
2292 l->stats.recv_states++;
2293 if (msg_probe(hdr))
2294 l->stats.recv_probes++;
2295
2296 if (!tipc_link_is_up(l)) {
2297 if (l->state == LINK_ESTABLISHING)
2298 rc = TIPC_LINK_UP_EVT;
2299 break;
2300 }
2301
2302 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2303 &l->mon_state, l->bearer_id);
2304
2305 /* Send NACK if peer has sent pkts we haven't received yet */
2306 if ((reply || msg_is_keepalive(hdr)) &&
2307 more(peers_snd_nxt, rcv_nxt) &&
2308 !tipc_link_is_synching(l) &&
2309 skb_queue_empty(&l->deferdq))
2310 rcvgap = peers_snd_nxt - l->rcv_nxt;
2311 if (rcvgap || reply)
2312 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2313 rcvgap, 0, 0, xmitq);
2314
2315 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2316 &retransmitted, &rc);
2317 if (gap)
2318 l->stats.recv_nacks++;
2319 if (released || retransmitted)
2320 tipc_link_update_cwin(l, released, retransmitted);
2321 if (released)
2322 tipc_link_advance_backlog(l, xmitq);
2323 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2324 link_prepare_wakeup(l);
2325 }
2326exit:
2327 kfree_skb(skb);
2328 return rc;
2329}
2330
2331/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2332 */
2333static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2334 u16 peers_snd_nxt,
2335 struct sk_buff_head *xmitq)
2336{
2337 struct sk_buff *skb;
2338 struct tipc_msg *hdr;
2339 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2340 u16 ack = l->rcv_nxt - 1;
2341 u16 gap_to = peers_snd_nxt - 1;
2342
2343 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2344 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2345 if (!skb)
2346 return false;
2347 hdr = buf_msg(skb);
2348 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2349 msg_set_bcast_ack(hdr, ack);
2350 msg_set_bcgap_after(hdr, ack);
2351 if (dfrd_skb)
2352 gap_to = buf_seqno(dfrd_skb) - 1;
2353 msg_set_bcgap_to(hdr, gap_to);
2354 msg_set_non_seq(hdr, bcast);
2355 __skb_queue_tail(xmitq, skb);
2356 return true;
2357}
2358
2359/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2360 *
2361 * Give a newly added peer node the sequence number where it should
2362 * start receiving and acking broadcast packets.
2363 */
2364static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2365 struct sk_buff_head *xmitq)
2366{
2367 struct sk_buff_head list;
2368
2369 __skb_queue_head_init(&list);
2370 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2371 return;
2372 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2373 tipc_link_xmit(l, &list, xmitq);
2374}
2375
2376/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2377 */
2378void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2379{
2380 int mtyp = msg_type(hdr);
2381 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2382
2383 if (tipc_link_is_up(l))
2384 return;
2385
2386 if (msg_user(hdr) == BCAST_PROTOCOL) {
2387 l->rcv_nxt = peers_snd_nxt;
2388 l->state = LINK_ESTABLISHED;
2389 return;
2390 }
2391
2392 if (l->peer_caps & TIPC_BCAST_SYNCH)
2393 return;
2394
2395 if (msg_peer_node_is_up(hdr))
2396 return;
2397
2398 /* Compatibility: accept older, less safe initial synch data */
2399 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2400 l->rcv_nxt = peers_snd_nxt;
2401}
2402
2403/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2404 */
2405int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2406 struct sk_buff_head *xmitq)
2407{
2408 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2409 int rc = 0;
2410
2411 if (!tipc_link_is_up(l))
2412 return rc;
2413
2414 if (!msg_peer_node_is_up(hdr))
2415 return rc;
2416
2417 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2418 if (msg_ack(hdr))
2419 l->bc_peer_is_up = true;
2420
2421 if (!l->bc_peer_is_up)
2422 return rc;
2423
2424 /* Ignore if peers_snd_nxt goes beyond receive window */
2425 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2426 return rc;
2427
2428 l->snd_nxt = peers_snd_nxt;
2429 if (link_bc_rcv_gap(l))
2430 rc |= TIPC_LINK_SND_STATE;
2431
2432 /* Return now if sender supports nack via STATE messages */
2433 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2434 return rc;
2435
2436 /* Otherwise, be backwards compatible */
2437
2438 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2439 l->nack_state = BC_NACK_SND_CONDITIONAL;
2440 return 0;
2441 }
2442
2443 /* Don't NACK if one was recently sent or peeked */
2444 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2445 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2446 return 0;
2447 }
2448
2449 /* Conditionally delay NACK sending until next synch rcv */
2450 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2451 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2452 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2453 return 0;
2454 }
2455
2456 /* Send NACK now but suppress next one */
2457 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2458 l->nack_state = BC_NACK_SND_SUPPRESS;
2459 return 0;
2460}
2461
2462int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2463 struct tipc_gap_ack_blks *ga,
2464 struct sk_buff_head *xmitq,
2465 struct sk_buff_head *retrq)
2466{
2467 struct tipc_link *l = r->bc_sndlink;
2468 bool unused = false;
2469 int rc = 0;
2470
2471 if (!tipc_link_is_up(r) || !r->bc_peer_is_up)
2472 return 0;
2473
2474 if (gap) {
2475 l->stats.recv_nacks++;
2476 r->stats.recv_nacks++;
2477 }
2478
2479 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2480 return 0;
2481
2482 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2483 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2484
2485 tipc_link_advance_backlog(l, xmitq);
2486 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2487 link_prepare_wakeup(l);
2488
2489 return rc;
2490}
2491
2492/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2493 * This function is here for backwards compatibility, since
2494 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2495 */
2496int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2497 struct sk_buff_head *xmitq)
2498{
2499 struct tipc_msg *hdr = buf_msg(skb);
2500 u32 dnode = msg_destnode(hdr);
2501 int mtyp = msg_type(hdr);
2502 u16 acked = msg_bcast_ack(hdr);
2503 u16 from = acked + 1;
2504 u16 to = msg_bcgap_to(hdr);
2505 u16 peers_snd_nxt = to + 1;
2506 int rc = 0;
2507
2508 kfree_skb(skb);
2509
2510 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2511 return 0;
2512
2513 if (mtyp != STATE_MSG)
2514 return 0;
2515
2516 if (dnode == tipc_own_addr(l->net)) {
2517 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2518 xmitq);
2519 l->stats.recv_nacks++;
2520 return rc;
2521 }
2522
2523 /* Msg for other node => suppress own NACK at next sync if applicable */
2524 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2525 l->nack_state = BC_NACK_SND_SUPPRESS;
2526
2527 return 0;
2528}
2529
2530void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2531{
2532 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2533
2534 l->min_win = min_win;
2535 l->ssthresh = max_win;
2536 l->max_win = max_win;
2537 l->window = min_win;
2538 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2539 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2540 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2541 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2542 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2543}
2544
2545/**
2546 * tipc_link_reset_stats - reset link statistics
2547 * @l: pointer to link
2548 */
2549void tipc_link_reset_stats(struct tipc_link *l)
2550{
2551 memset(&l->stats, 0, sizeof(l->stats));
2552}
2553
2554static void link_print(struct tipc_link *l, const char *str)
2555{
2556 struct sk_buff *hskb = skb_peek(&l->transmq);
2557 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2558 u16 tail = l->snd_nxt - 1;
2559
2560 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2561 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2562 skb_queue_len(&l->transmq), head, tail,
2563 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2564}
2565
2566/* Parse and validate nested (link) properties valid for media, bearer and link
2567 */
2568int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2569{
2570 int err;
2571
2572 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2573 tipc_nl_prop_policy, NULL);
2574 if (err)
2575 return err;
2576
2577 if (props[TIPC_NLA_PROP_PRIO]) {
2578 u32 prio;
2579
2580 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2581 if (prio > TIPC_MAX_LINK_PRI)
2582 return -EINVAL;
2583 }
2584
2585 if (props[TIPC_NLA_PROP_TOL]) {
2586 u32 tol;
2587
2588 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2589 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2590 return -EINVAL;
2591 }
2592
2593 if (props[TIPC_NLA_PROP_WIN]) {
2594 u32 max_win;
2595
2596 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2597 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2598 return -EINVAL;
2599 }
2600
2601 return 0;
2602}
2603
2604static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2605{
2606 int i;
2607 struct nlattr *stats;
2608
2609 struct nla_map {
2610 u32 key;
2611 u32 val;
2612 };
2613
2614 struct nla_map map[] = {
2615 {TIPC_NLA_STATS_RX_INFO, 0},
2616 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2617 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2618 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2619 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2620 {TIPC_NLA_STATS_TX_INFO, 0},
2621 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2622 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2623 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2624 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2625 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2626 s->msg_length_counts : 1},
2627 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2628 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2629 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2630 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2631 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2632 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2633 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2634 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2635 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2636 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2637 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2638 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2639 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2640 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2641 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2642 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2643 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2644 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2645 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2646 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2647 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2648 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2649 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2650 };
2651
2652 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2653 if (!stats)
2654 return -EMSGSIZE;
2655
2656 for (i = 0; i < ARRAY_SIZE(map); i++)
2657 if (nla_put_u32(skb, map[i].key, map[i].val))
2658 goto msg_full;
2659
2660 nla_nest_end(skb, stats);
2661
2662 return 0;
2663msg_full:
2664 nla_nest_cancel(skb, stats);
2665
2666 return -EMSGSIZE;
2667}
2668
2669/* Caller should hold appropriate locks to protect the link */
2670int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2671 struct tipc_link *link, int nlflags)
2672{
2673 u32 self = tipc_own_addr(net);
2674 struct nlattr *attrs;
2675 struct nlattr *prop;
2676 void *hdr;
2677 int err;
2678
2679 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2680 nlflags, TIPC_NL_LINK_GET);
2681 if (!hdr)
2682 return -EMSGSIZE;
2683
2684 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2685 if (!attrs)
2686 goto msg_full;
2687
2688 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2689 goto attr_msg_full;
2690 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2691 goto attr_msg_full;
2692 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2693 goto attr_msg_full;
2694 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2695 goto attr_msg_full;
2696 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2697 goto attr_msg_full;
2698
2699 if (tipc_link_is_up(link))
2700 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2701 goto attr_msg_full;
2702 if (link->active)
2703 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2704 goto attr_msg_full;
2705
2706 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2707 if (!prop)
2708 goto attr_msg_full;
2709 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2710 goto prop_msg_full;
2711 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2712 goto prop_msg_full;
2713 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2714 link->window))
2715 goto prop_msg_full;
2716 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2717 goto prop_msg_full;
2718 nla_nest_end(msg->skb, prop);
2719
2720 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2721 if (err)
2722 goto attr_msg_full;
2723
2724 nla_nest_end(msg->skb, attrs);
2725 genlmsg_end(msg->skb, hdr);
2726
2727 return 0;
2728
2729prop_msg_full:
2730 nla_nest_cancel(msg->skb, prop);
2731attr_msg_full:
2732 nla_nest_cancel(msg->skb, attrs);
2733msg_full:
2734 genlmsg_cancel(msg->skb, hdr);
2735
2736 return -EMSGSIZE;
2737}
2738
2739static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2740 struct tipc_stats *stats)
2741{
2742 int i;
2743 struct nlattr *nest;
2744
2745 struct nla_map {
2746 __u32 key;
2747 __u32 val;
2748 };
2749
2750 struct nla_map map[] = {
2751 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2752 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2753 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2754 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2755 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2756 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2757 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2758 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2759 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2760 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2761 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2762 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2763 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2764 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2765 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2766 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2767 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2768 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2769 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2770 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2771 };
2772
2773 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2774 if (!nest)
2775 return -EMSGSIZE;
2776
2777 for (i = 0; i < ARRAY_SIZE(map); i++)
2778 if (nla_put_u32(skb, map[i].key, map[i].val))
2779 goto msg_full;
2780
2781 nla_nest_end(skb, nest);
2782
2783 return 0;
2784msg_full:
2785 nla_nest_cancel(skb, nest);
2786
2787 return -EMSGSIZE;
2788}
2789
2790int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2791 struct tipc_link *bcl)
2792{
2793 int err;
2794 void *hdr;
2795 struct nlattr *attrs;
2796 struct nlattr *prop;
2797 u32 bc_mode = tipc_bcast_get_mode(net);
2798 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2799
2800 if (!bcl)
2801 return 0;
2802
2803 tipc_bcast_lock(net);
2804
2805 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2806 NLM_F_MULTI, TIPC_NL_LINK_GET);
2807 if (!hdr) {
2808 tipc_bcast_unlock(net);
2809 return -EMSGSIZE;
2810 }
2811
2812 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2813 if (!attrs)
2814 goto msg_full;
2815
2816 /* The broadcast link is always up */
2817 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2818 goto attr_msg_full;
2819
2820 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2821 goto attr_msg_full;
2822 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2823 goto attr_msg_full;
2824 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2825 goto attr_msg_full;
2826 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2827 goto attr_msg_full;
2828
2829 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2830 if (!prop)
2831 goto attr_msg_full;
2832 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2833 goto prop_msg_full;
2834 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2835 goto prop_msg_full;
2836 if (bc_mode & BCLINK_MODE_SEL)
2837 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2838 bc_ratio))
2839 goto prop_msg_full;
2840 nla_nest_end(msg->skb, prop);
2841
2842 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2843 if (err)
2844 goto attr_msg_full;
2845
2846 tipc_bcast_unlock(net);
2847 nla_nest_end(msg->skb, attrs);
2848 genlmsg_end(msg->skb, hdr);
2849
2850 return 0;
2851
2852prop_msg_full:
2853 nla_nest_cancel(msg->skb, prop);
2854attr_msg_full:
2855 nla_nest_cancel(msg->skb, attrs);
2856msg_full:
2857 tipc_bcast_unlock(net);
2858 genlmsg_cancel(msg->skb, hdr);
2859
2860 return -EMSGSIZE;
2861}
2862
2863void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2864 struct sk_buff_head *xmitq)
2865{
2866 l->tolerance = tol;
2867 if (l->bc_rcvlink)
2868 l->bc_rcvlink->tolerance = tol;
2869 if (tipc_link_is_up(l))
2870 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2871}
2872
2873void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2874 struct sk_buff_head *xmitq)
2875{
2876 l->priority = prio;
2877 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2878}
2879
2880void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2881{
2882 l->abort_limit = limit;
2883}
2884
2885/**
2886 * tipc_link_dump - dump TIPC link data
2887 * @l: tipc link to be dumped
2888 * @dqueues: bitmask to decide if any link queue to be dumped?
2889 * - TIPC_DUMP_NONE: don't dump link queues
2890 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2891 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2892 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2893 * - TIPC_DUMP_INPUTQ: dump link input queue
2894 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2895 * - TIPC_DUMP_ALL: dump all the link queues above
2896 * @buf: returned buffer of dump data in format
2897 */
2898int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2899{
2900 int i = 0;
2901 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2902 struct sk_buff_head *list;
2903 struct sk_buff *hskb, *tskb;
2904 u32 len;
2905
2906 if (!l) {
2907 i += scnprintf(buf, sz, "link data: (null)\n");
2908 return i;
2909 }
2910
2911 i += scnprintf(buf, sz, "link data: %x", l->addr);
2912 i += scnprintf(buf + i, sz - i, " %x", l->state);
2913 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2914 i += scnprintf(buf + i, sz - i, " %u", l->session);
2915 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2916 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2917 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2918 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2919 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2920 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2921 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2922 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2923 i += scnprintf(buf + i, sz - i, " %u", 0);
2924 i += scnprintf(buf + i, sz - i, " %u", 0);
2925 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2926
2927 list = &l->transmq;
2928 len = skb_queue_len(list);
2929 hskb = skb_peek(list);
2930 tskb = skb_peek_tail(list);
2931 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2932 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2933 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2934
2935 list = &l->deferdq;
2936 len = skb_queue_len(list);
2937 hskb = skb_peek(list);
2938 tskb = skb_peek_tail(list);
2939 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2940 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2941 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2942
2943 list = &l->backlogq;
2944 len = skb_queue_len(list);
2945 hskb = skb_peek(list);
2946 tskb = skb_peek_tail(list);
2947 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2948 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2949 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2950
2951 list = l->inputq;
2952 len = skb_queue_len(list);
2953 hskb = skb_peek(list);
2954 tskb = skb_peek_tail(list);
2955 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2956 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2957 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2958
2959 if (dqueues & TIPC_DUMP_TRANSMQ) {
2960 i += scnprintf(buf + i, sz - i, "transmq: ");
2961 i += tipc_list_dump(&l->transmq, false, buf + i);
2962 }
2963 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2964 i += scnprintf(buf + i, sz - i,
2965 "backlogq: <%u %u %u %u %u>, ",
2966 l->backlog[TIPC_LOW_IMPORTANCE].len,
2967 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2968 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2969 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2970 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2971 i += tipc_list_dump(&l->backlogq, false, buf + i);
2972 }
2973 if (dqueues & TIPC_DUMP_DEFERDQ) {
2974 i += scnprintf(buf + i, sz - i, "deferdq: ");
2975 i += tipc_list_dump(&l->deferdq, false, buf + i);
2976 }
2977 if (dqueues & TIPC_DUMP_INPUTQ) {
2978 i += scnprintf(buf + i, sz - i, "inputq: ");
2979 i += tipc_list_dump(l->inputq, false, buf + i);
2980 }
2981 if (dqueues & TIPC_DUMP_WAKEUP) {
2982 i += scnprintf(buf + i, sz - i, "wakeup: ");
2983 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2984 }
2985
2986 return i;
2987}