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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 * @session: session to be used by link
124 * @snd_nxt_state: next send seq number
125 * @rcv_nxt_state: next rcv seq number
126 * @in_session: have received ACTIVATE_MSG from peer
127 * @active: link is active
128 * @if_name: associated interface name
129 * @rst_cnt: link reset counter
130 * @drop_point: seq number for failover handling (FIXME)
131 * @failover_reasm_skb: saved failover msg ptr (FIXME)
132 * @failover_deferdq: deferred message queue for failover processing (FIXME)
133 * @transmq: the link's transmit queue
134 * @backlog: link's backlog by priority (importance)
135 * @snd_nxt: next sequence number to be used
136 * @rcv_unacked: # messages read by user, but not yet acked back to peer
137 * @deferdq: deferred receive queue
138 * @window: sliding window size for congestion handling
139 * @min_win: minimal send window to be used by link
140 * @ssthresh: slow start threshold for congestion handling
141 * @max_win: maximal send window to be used by link
142 * @cong_acks: congestion acks for congestion avoidance (FIXME)
143 * @checkpoint: seq number for congestion window size handling
144 * @reasm_tnlmsg: fragmentation/reassembly area for tunnel protocol message
145 * @last_gap: last gap ack blocks for bcast (FIXME)
146 * @last_ga: ptr to gap ack blocks
147 * @bc_rcvlink: the peer specific link used for broadcast reception
148 * @bc_sndlink: the namespace global link used for broadcast sending
149 * @nack_state: bcast nack state
150 * @bc_peer_is_up: peer has acked the bcast init msg
151 */
152struct tipc_link {
153 u32 addr;
154 char name[TIPC_MAX_LINK_NAME];
155 struct net *net;
156
157 /* Management and link supervision data */
158 u16 peer_session;
159 u16 session;
160 u16 snd_nxt_state;
161 u16 rcv_nxt_state;
162 u32 peer_bearer_id;
163 u32 bearer_id;
164 u32 tolerance;
165 u32 abort_limit;
166 u32 state;
167 u16 peer_caps;
168 bool in_session;
169 bool active;
170 u32 silent_intv_cnt;
171 char if_name[TIPC_MAX_IF_NAME];
172 u32 priority;
173 char net_plane;
174 struct tipc_mon_state mon_state;
175 u16 rst_cnt;
176
177 /* Failover/synch */
178 u16 drop_point;
179 struct sk_buff *failover_reasm_skb;
180 struct sk_buff_head failover_deferdq;
181
182 /* Max packet negotiation */
183 u16 mtu;
184 u16 advertised_mtu;
185
186 /* Sending */
187 struct sk_buff_head transmq;
188 struct sk_buff_head backlogq;
189 struct {
190 u16 len;
191 u16 limit;
192 struct sk_buff *target_bskb;
193 } backlog[5];
194 u16 snd_nxt;
195
196 /* Reception */
197 u16 rcv_nxt;
198 u32 rcv_unacked;
199 struct sk_buff_head deferdq;
200 struct sk_buff_head *inputq;
201 struct sk_buff_head *namedq;
202
203 /* Congestion handling */
204 struct sk_buff_head wakeupq;
205 u16 window;
206 u16 min_win;
207 u16 ssthresh;
208 u16 max_win;
209 u16 cong_acks;
210 u16 checkpoint;
211
212 /* Fragmentation/reassembly */
213 struct sk_buff *reasm_buf;
214 struct sk_buff *reasm_tnlmsg;
215
216 /* Broadcast */
217 u16 ackers;
218 u16 acked;
219 u16 last_gap;
220 struct tipc_gap_ack_blks *last_ga;
221 struct tipc_link *bc_rcvlink;
222 struct tipc_link *bc_sndlink;
223 u8 nack_state;
224 bool bc_peer_is_up;
225
226 /* Statistics */
227 struct tipc_stats stats;
228};
229
230/*
231 * Error message prefixes
232 */
233static const char *link_co_err = "Link tunneling error, ";
234static const char *link_rst_msg = "Resetting link ";
235
236/* Send states for broadcast NACKs
237 */
238enum {
239 BC_NACK_SND_CONDITIONAL,
240 BC_NACK_SND_UNCONDITIONAL,
241 BC_NACK_SND_SUPPRESS,
242};
243
244#define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
245#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
246
247/* Link FSM states:
248 */
249enum {
250 LINK_ESTABLISHED = 0xe,
251 LINK_ESTABLISHING = 0xe << 4,
252 LINK_RESET = 0x1 << 8,
253 LINK_RESETTING = 0x2 << 12,
254 LINK_PEER_RESET = 0xd << 16,
255 LINK_FAILINGOVER = 0xf << 20,
256 LINK_SYNCHING = 0xc << 24
257};
258
259/* Link FSM state checking routines
260 */
261static int link_is_up(struct tipc_link *l)
262{
263 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
264}
265
266static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
267 struct sk_buff_head *xmitq);
268static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
269 bool probe_reply, u16 rcvgap,
270 int tolerance, int priority,
271 struct sk_buff_head *xmitq);
272static void link_print(struct tipc_link *l, const char *str);
273static int tipc_link_build_nack_msg(struct tipc_link *l,
274 struct sk_buff_head *xmitq);
275static void tipc_link_build_bc_init_msg(struct tipc_link *l,
276 struct sk_buff_head *xmitq);
277static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
278 struct tipc_link *l, u8 start_index);
279static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
280static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
281 u16 acked, u16 gap,
282 struct tipc_gap_ack_blks *ga,
283 struct sk_buff_head *xmitq,
284 bool *retransmitted, int *rc);
285static void tipc_link_update_cwin(struct tipc_link *l, int released,
286 bool retransmitted);
287/*
288 * Simple non-static link routines (i.e. referenced outside this file)
289 */
290bool tipc_link_is_up(struct tipc_link *l)
291{
292 return link_is_up(l);
293}
294
295bool tipc_link_peer_is_down(struct tipc_link *l)
296{
297 return l->state == LINK_PEER_RESET;
298}
299
300bool tipc_link_is_reset(struct tipc_link *l)
301{
302 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
303}
304
305bool tipc_link_is_establishing(struct tipc_link *l)
306{
307 return l->state == LINK_ESTABLISHING;
308}
309
310bool tipc_link_is_synching(struct tipc_link *l)
311{
312 return l->state == LINK_SYNCHING;
313}
314
315bool tipc_link_is_failingover(struct tipc_link *l)
316{
317 return l->state == LINK_FAILINGOVER;
318}
319
320bool tipc_link_is_blocked(struct tipc_link *l)
321{
322 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
323}
324
325static bool link_is_bc_sndlink(struct tipc_link *l)
326{
327 return !l->bc_sndlink;
328}
329
330static bool link_is_bc_rcvlink(struct tipc_link *l)
331{
332 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
333}
334
335void tipc_link_set_active(struct tipc_link *l, bool active)
336{
337 l->active = active;
338}
339
340u32 tipc_link_id(struct tipc_link *l)
341{
342 return l->peer_bearer_id << 16 | l->bearer_id;
343}
344
345int tipc_link_min_win(struct tipc_link *l)
346{
347 return l->min_win;
348}
349
350int tipc_link_max_win(struct tipc_link *l)
351{
352 return l->max_win;
353}
354
355int tipc_link_prio(struct tipc_link *l)
356{
357 return l->priority;
358}
359
360unsigned long tipc_link_tolerance(struct tipc_link *l)
361{
362 return l->tolerance;
363}
364
365struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
366{
367 return l->inputq;
368}
369
370char tipc_link_plane(struct tipc_link *l)
371{
372 return l->net_plane;
373}
374
375struct net *tipc_link_net(struct tipc_link *l)
376{
377 return l->net;
378}
379
380void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
381{
382 l->peer_caps = capabilities;
383}
384
385void tipc_link_add_bc_peer(struct tipc_link *snd_l,
386 struct tipc_link *uc_l,
387 struct sk_buff_head *xmitq)
388{
389 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
390
391 snd_l->ackers++;
392 rcv_l->acked = snd_l->snd_nxt - 1;
393 snd_l->state = LINK_ESTABLISHED;
394 tipc_link_build_bc_init_msg(uc_l, xmitq);
395}
396
397void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
398 struct tipc_link *rcv_l,
399 struct sk_buff_head *xmitq)
400{
401 u16 ack = snd_l->snd_nxt - 1;
402
403 snd_l->ackers--;
404 rcv_l->bc_peer_is_up = true;
405 rcv_l->state = LINK_ESTABLISHED;
406 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
407 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
408 tipc_link_reset(rcv_l);
409 rcv_l->state = LINK_RESET;
410 if (!snd_l->ackers) {
411 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
412 tipc_link_reset(snd_l);
413 snd_l->state = LINK_RESET;
414 __skb_queue_purge(xmitq);
415 }
416}
417
418int tipc_link_bc_peers(struct tipc_link *l)
419{
420 return l->ackers;
421}
422
423static u16 link_bc_rcv_gap(struct tipc_link *l)
424{
425 struct sk_buff *skb = skb_peek(&l->deferdq);
426 u16 gap = 0;
427
428 if (more(l->snd_nxt, l->rcv_nxt))
429 gap = l->snd_nxt - l->rcv_nxt;
430 if (skb)
431 gap = buf_seqno(skb) - l->rcv_nxt;
432 return gap;
433}
434
435void tipc_link_set_mtu(struct tipc_link *l, int mtu)
436{
437 l->mtu = mtu;
438}
439
440int tipc_link_mtu(struct tipc_link *l)
441{
442 return l->mtu;
443}
444
445int tipc_link_mss(struct tipc_link *l)
446{
447#ifdef CONFIG_TIPC_CRYPTO
448 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
449#else
450 return l->mtu - INT_H_SIZE;
451#endif
452}
453
454u16 tipc_link_rcv_nxt(struct tipc_link *l)
455{
456 return l->rcv_nxt;
457}
458
459u16 tipc_link_acked(struct tipc_link *l)
460{
461 return l->acked;
462}
463
464char *tipc_link_name(struct tipc_link *l)
465{
466 return l->name;
467}
468
469u32 tipc_link_state(struct tipc_link *l)
470{
471 return l->state;
472}
473
474/**
475 * tipc_link_create - create a new link
476 * @net: pointer to associated network namespace
477 * @if_name: associated interface name
478 * @bearer_id: id (index) of associated bearer
479 * @tolerance: link tolerance to be used by link
480 * @net_plane: network plane (A,B,c..) this link belongs to
481 * @mtu: mtu to be advertised by link
482 * @priority: priority to be used by link
483 * @min_win: minimal send window to be used by link
484 * @max_win: maximal send window to be used by link
485 * @session: session to be used by link
486 * @peer: node id of peer node
487 * @peer_caps: bitmap describing peer node capabilities
488 * @bc_sndlink: the namespace global link used for broadcast sending
489 * @bc_rcvlink: the peer specific link used for broadcast reception
490 * @inputq: queue to put messages ready for delivery
491 * @namedq: queue to put binding table update messages ready for delivery
492 * @link: return value, pointer to put the created link
493 * @self: local unicast link id
494 * @peer_id: 128-bit ID of peer
495 *
496 * Return: true if link was created, otherwise false
497 */
498bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
499 int tolerance, char net_plane, u32 mtu, int priority,
500 u32 min_win, u32 max_win, u32 session, u32 self,
501 u32 peer, u8 *peer_id, u16 peer_caps,
502 struct tipc_link *bc_sndlink,
503 struct tipc_link *bc_rcvlink,
504 struct sk_buff_head *inputq,
505 struct sk_buff_head *namedq,
506 struct tipc_link **link)
507{
508 char peer_str[NODE_ID_STR_LEN] = {0,};
509 char self_str[NODE_ID_STR_LEN] = {0,};
510 struct tipc_link *l;
511
512 l = kzalloc(sizeof(*l), GFP_ATOMIC);
513 if (!l)
514 return false;
515 *link = l;
516 l->session = session;
517
518 /* Set link name for unicast links only */
519 if (peer_id) {
520 tipc_nodeid2string(self_str, tipc_own_id(net));
521 if (strlen(self_str) > 16)
522 sprintf(self_str, "%x", self);
523 tipc_nodeid2string(peer_str, peer_id);
524 if (strlen(peer_str) > 16)
525 sprintf(peer_str, "%x", peer);
526 }
527 /* Peer i/f name will be completed by reset/activate message */
528 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
529 self_str, if_name, peer_str);
530
531 strcpy(l->if_name, if_name);
532 l->addr = peer;
533 l->peer_caps = peer_caps;
534 l->net = net;
535 l->in_session = false;
536 l->bearer_id = bearer_id;
537 l->tolerance = tolerance;
538 if (bc_rcvlink)
539 bc_rcvlink->tolerance = tolerance;
540 l->net_plane = net_plane;
541 l->advertised_mtu = mtu;
542 l->mtu = mtu;
543 l->priority = priority;
544 tipc_link_set_queue_limits(l, min_win, max_win);
545 l->ackers = 1;
546 l->bc_sndlink = bc_sndlink;
547 l->bc_rcvlink = bc_rcvlink;
548 l->inputq = inputq;
549 l->namedq = namedq;
550 l->state = LINK_RESETTING;
551 __skb_queue_head_init(&l->transmq);
552 __skb_queue_head_init(&l->backlogq);
553 __skb_queue_head_init(&l->deferdq);
554 __skb_queue_head_init(&l->failover_deferdq);
555 skb_queue_head_init(&l->wakeupq);
556 skb_queue_head_init(l->inputq);
557 return true;
558}
559
560/**
561 * tipc_link_bc_create - create new link to be used for broadcast
562 * @net: pointer to associated network namespace
563 * @mtu: mtu to be used initially if no peers
564 * @min_win: minimal send window to be used by link
565 * @max_win: maximal send window to be used by link
566 * @inputq: queue to put messages ready for delivery
567 * @namedq: queue to put binding table update messages ready for delivery
568 * @link: return value, pointer to put the created link
569 * @ownnode: identity of own node
570 * @peer: node id of peer node
571 * @peer_id: 128-bit ID of peer
572 * @peer_caps: bitmap describing peer node capabilities
573 * @bc_sndlink: the namespace global link used for broadcast sending
574 *
575 * Return: true if link was created, otherwise false
576 */
577bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
578 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
579 struct sk_buff_head *inputq,
580 struct sk_buff_head *namedq,
581 struct tipc_link *bc_sndlink,
582 struct tipc_link **link)
583{
584 struct tipc_link *l;
585
586 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
587 max_win, 0, ownnode, peer, NULL, peer_caps,
588 bc_sndlink, NULL, inputq, namedq, link))
589 return false;
590
591 l = *link;
592 if (peer_id) {
593 char peer_str[NODE_ID_STR_LEN] = {0,};
594
595 tipc_nodeid2string(peer_str, peer_id);
596 if (strlen(peer_str) > 16)
597 sprintf(peer_str, "%x", peer);
598 /* Broadcast receiver link name: "broadcast-link:<peer>" */
599 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
600 peer_str);
601 } else {
602 strcpy(l->name, tipc_bclink_name);
603 }
604 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
605 tipc_link_reset(l);
606 l->state = LINK_RESET;
607 l->ackers = 0;
608 l->bc_rcvlink = l;
609
610 /* Broadcast send link is always up */
611 if (link_is_bc_sndlink(l))
612 l->state = LINK_ESTABLISHED;
613
614 /* Disable replicast if even a single peer doesn't support it */
615 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
616 tipc_bcast_toggle_rcast(net, false);
617
618 return true;
619}
620
621/**
622 * tipc_link_fsm_evt - link finite state machine
623 * @l: pointer to link
624 * @evt: state machine event to be processed
625 */
626int tipc_link_fsm_evt(struct tipc_link *l, int evt)
627{
628 int rc = 0;
629 int old_state = l->state;
630
631 switch (l->state) {
632 case LINK_RESETTING:
633 switch (evt) {
634 case LINK_PEER_RESET_EVT:
635 l->state = LINK_PEER_RESET;
636 break;
637 case LINK_RESET_EVT:
638 l->state = LINK_RESET;
639 break;
640 case LINK_FAILURE_EVT:
641 case LINK_FAILOVER_BEGIN_EVT:
642 case LINK_ESTABLISH_EVT:
643 case LINK_FAILOVER_END_EVT:
644 case LINK_SYNCH_BEGIN_EVT:
645 case LINK_SYNCH_END_EVT:
646 default:
647 goto illegal_evt;
648 }
649 break;
650 case LINK_RESET:
651 switch (evt) {
652 case LINK_PEER_RESET_EVT:
653 l->state = LINK_ESTABLISHING;
654 break;
655 case LINK_FAILOVER_BEGIN_EVT:
656 l->state = LINK_FAILINGOVER;
657 break;
658 case LINK_FAILURE_EVT:
659 case LINK_RESET_EVT:
660 case LINK_ESTABLISH_EVT:
661 case LINK_FAILOVER_END_EVT:
662 break;
663 case LINK_SYNCH_BEGIN_EVT:
664 case LINK_SYNCH_END_EVT:
665 default:
666 goto illegal_evt;
667 }
668 break;
669 case LINK_PEER_RESET:
670 switch (evt) {
671 case LINK_RESET_EVT:
672 l->state = LINK_ESTABLISHING;
673 break;
674 case LINK_PEER_RESET_EVT:
675 case LINK_ESTABLISH_EVT:
676 case LINK_FAILURE_EVT:
677 break;
678 case LINK_SYNCH_BEGIN_EVT:
679 case LINK_SYNCH_END_EVT:
680 case LINK_FAILOVER_BEGIN_EVT:
681 case LINK_FAILOVER_END_EVT:
682 default:
683 goto illegal_evt;
684 }
685 break;
686 case LINK_FAILINGOVER:
687 switch (evt) {
688 case LINK_FAILOVER_END_EVT:
689 l->state = LINK_RESET;
690 break;
691 case LINK_PEER_RESET_EVT:
692 case LINK_RESET_EVT:
693 case LINK_ESTABLISH_EVT:
694 case LINK_FAILURE_EVT:
695 break;
696 case LINK_FAILOVER_BEGIN_EVT:
697 case LINK_SYNCH_BEGIN_EVT:
698 case LINK_SYNCH_END_EVT:
699 default:
700 goto illegal_evt;
701 }
702 break;
703 case LINK_ESTABLISHING:
704 switch (evt) {
705 case LINK_ESTABLISH_EVT:
706 l->state = LINK_ESTABLISHED;
707 break;
708 case LINK_FAILOVER_BEGIN_EVT:
709 l->state = LINK_FAILINGOVER;
710 break;
711 case LINK_RESET_EVT:
712 l->state = LINK_RESET;
713 break;
714 case LINK_FAILURE_EVT:
715 case LINK_PEER_RESET_EVT:
716 case LINK_SYNCH_BEGIN_EVT:
717 case LINK_FAILOVER_END_EVT:
718 break;
719 case LINK_SYNCH_END_EVT:
720 default:
721 goto illegal_evt;
722 }
723 break;
724 case LINK_ESTABLISHED:
725 switch (evt) {
726 case LINK_PEER_RESET_EVT:
727 l->state = LINK_PEER_RESET;
728 rc |= TIPC_LINK_DOWN_EVT;
729 break;
730 case LINK_FAILURE_EVT:
731 l->state = LINK_RESETTING;
732 rc |= TIPC_LINK_DOWN_EVT;
733 break;
734 case LINK_RESET_EVT:
735 l->state = LINK_RESET;
736 break;
737 case LINK_ESTABLISH_EVT:
738 case LINK_SYNCH_END_EVT:
739 break;
740 case LINK_SYNCH_BEGIN_EVT:
741 l->state = LINK_SYNCHING;
742 break;
743 case LINK_FAILOVER_BEGIN_EVT:
744 case LINK_FAILOVER_END_EVT:
745 default:
746 goto illegal_evt;
747 }
748 break;
749 case LINK_SYNCHING:
750 switch (evt) {
751 case LINK_PEER_RESET_EVT:
752 l->state = LINK_PEER_RESET;
753 rc |= TIPC_LINK_DOWN_EVT;
754 break;
755 case LINK_FAILURE_EVT:
756 l->state = LINK_RESETTING;
757 rc |= TIPC_LINK_DOWN_EVT;
758 break;
759 case LINK_RESET_EVT:
760 l->state = LINK_RESET;
761 break;
762 case LINK_ESTABLISH_EVT:
763 case LINK_SYNCH_BEGIN_EVT:
764 break;
765 case LINK_SYNCH_END_EVT:
766 l->state = LINK_ESTABLISHED;
767 break;
768 case LINK_FAILOVER_BEGIN_EVT:
769 case LINK_FAILOVER_END_EVT:
770 default:
771 goto illegal_evt;
772 }
773 break;
774 default:
775 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
776 }
777 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
778 return rc;
779illegal_evt:
780 pr_err("Illegal FSM event %x in state %x on link %s\n",
781 evt, l->state, l->name);
782 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
783 return rc;
784}
785
786/* link_profile_stats - update statistical profiling of traffic
787 */
788static void link_profile_stats(struct tipc_link *l)
789{
790 struct sk_buff *skb;
791 struct tipc_msg *msg;
792 int length;
793
794 /* Update counters used in statistical profiling of send traffic */
795 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
796 l->stats.queue_sz_counts++;
797
798 skb = skb_peek(&l->transmq);
799 if (!skb)
800 return;
801 msg = buf_msg(skb);
802 length = msg_size(msg);
803
804 if (msg_user(msg) == MSG_FRAGMENTER) {
805 if (msg_type(msg) != FIRST_FRAGMENT)
806 return;
807 length = msg_size(msg_inner_hdr(msg));
808 }
809 l->stats.msg_lengths_total += length;
810 l->stats.msg_length_counts++;
811 if (length <= 64)
812 l->stats.msg_length_profile[0]++;
813 else if (length <= 256)
814 l->stats.msg_length_profile[1]++;
815 else if (length <= 1024)
816 l->stats.msg_length_profile[2]++;
817 else if (length <= 4096)
818 l->stats.msg_length_profile[3]++;
819 else if (length <= 16384)
820 l->stats.msg_length_profile[4]++;
821 else if (length <= 32768)
822 l->stats.msg_length_profile[5]++;
823 else
824 l->stats.msg_length_profile[6]++;
825}
826
827/**
828 * tipc_link_too_silent - check if link is "too silent"
829 * @l: tipc link to be checked
830 *
831 * Return: true if the link 'silent_intv_cnt' is about to reach the
832 * 'abort_limit' value, otherwise false
833 */
834bool tipc_link_too_silent(struct tipc_link *l)
835{
836 return (l->silent_intv_cnt + 2 > l->abort_limit);
837}
838
839/* tipc_link_timeout - perform periodic task as instructed from node timeout
840 */
841int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
842{
843 int mtyp = 0;
844 int rc = 0;
845 bool state = false;
846 bool probe = false;
847 bool setup = false;
848 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
849 u16 bc_acked = l->bc_rcvlink->acked;
850 struct tipc_mon_state *mstate = &l->mon_state;
851
852 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
853 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
854 switch (l->state) {
855 case LINK_ESTABLISHED:
856 case LINK_SYNCHING:
857 mtyp = STATE_MSG;
858 link_profile_stats(l);
859 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
860 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
861 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
862 state = bc_acked != bc_snt;
863 state |= l->bc_rcvlink->rcv_unacked;
864 state |= l->rcv_unacked;
865 state |= !skb_queue_empty(&l->transmq);
866 probe = mstate->probing;
867 probe |= l->silent_intv_cnt;
868 if (probe || mstate->monitoring)
869 l->silent_intv_cnt++;
870 probe |= !skb_queue_empty(&l->deferdq);
871 if (l->snd_nxt == l->checkpoint) {
872 tipc_link_update_cwin(l, 0, 0);
873 probe = true;
874 }
875 l->checkpoint = l->snd_nxt;
876 break;
877 case LINK_RESET:
878 setup = l->rst_cnt++ <= 4;
879 setup |= !(l->rst_cnt % 16);
880 mtyp = RESET_MSG;
881 break;
882 case LINK_ESTABLISHING:
883 setup = true;
884 mtyp = ACTIVATE_MSG;
885 break;
886 case LINK_PEER_RESET:
887 case LINK_RESETTING:
888 case LINK_FAILINGOVER:
889 break;
890 default:
891 break;
892 }
893
894 if (state || probe || setup)
895 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
896
897 return rc;
898}
899
900/**
901 * link_schedule_user - schedule a message sender for wakeup after congestion
902 * @l: congested link
903 * @hdr: header of message that is being sent
904 * Create pseudo msg to send back to user when congestion abates
905 */
906static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
907{
908 u32 dnode = tipc_own_addr(l->net);
909 u32 dport = msg_origport(hdr);
910 struct sk_buff *skb;
911
912 /* Create and schedule wakeup pseudo message */
913 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
914 dnode, l->addr, dport, 0, 0);
915 if (!skb)
916 return -ENOBUFS;
917 msg_set_dest_droppable(buf_msg(skb), true);
918 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
919 skb_queue_tail(&l->wakeupq, skb);
920 l->stats.link_congs++;
921 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
922 return -ELINKCONG;
923}
924
925/**
926 * link_prepare_wakeup - prepare users for wakeup after congestion
927 * @l: congested link
928 * Wake up a number of waiting users, as permitted by available space
929 * in the send queue
930 */
931static void link_prepare_wakeup(struct tipc_link *l)
932{
933 struct sk_buff_head *wakeupq = &l->wakeupq;
934 struct sk_buff_head *inputq = l->inputq;
935 struct sk_buff *skb, *tmp;
936 struct sk_buff_head tmpq;
937 int avail[5] = {0,};
938 int imp = 0;
939
940 __skb_queue_head_init(&tmpq);
941
942 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
943 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
944
945 skb_queue_walk_safe(wakeupq, skb, tmp) {
946 imp = TIPC_SKB_CB(skb)->chain_imp;
947 if (avail[imp] <= 0)
948 continue;
949 avail[imp]--;
950 __skb_unlink(skb, wakeupq);
951 __skb_queue_tail(&tmpq, skb);
952 }
953
954 spin_lock_bh(&inputq->lock);
955 skb_queue_splice_tail(&tmpq, inputq);
956 spin_unlock_bh(&inputq->lock);
957
958}
959
960/**
961 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
962 * the given skb should be next attempted
963 * @skb: skb to set a future retransmission time for
964 * @l: link the skb will be transmitted on
965 */
966static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
967 struct tipc_link *l)
968{
969 if (link_is_bc_sndlink(l))
970 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
971 else
972 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
973}
974
975void tipc_link_reset(struct tipc_link *l)
976{
977 struct sk_buff_head list;
978 u32 imp;
979
980 __skb_queue_head_init(&list);
981
982 l->in_session = false;
983 /* Force re-synch of peer session number before establishing */
984 l->peer_session--;
985 l->session++;
986 l->mtu = l->advertised_mtu;
987
988 spin_lock_bh(&l->wakeupq.lock);
989 skb_queue_splice_init(&l->wakeupq, &list);
990 spin_unlock_bh(&l->wakeupq.lock);
991
992 spin_lock_bh(&l->inputq->lock);
993 skb_queue_splice_init(&list, l->inputq);
994 spin_unlock_bh(&l->inputq->lock);
995
996 __skb_queue_purge(&l->transmq);
997 __skb_queue_purge(&l->deferdq);
998 __skb_queue_purge(&l->backlogq);
999 __skb_queue_purge(&l->failover_deferdq);
1000 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
1001 l->backlog[imp].len = 0;
1002 l->backlog[imp].target_bskb = NULL;
1003 }
1004 kfree_skb(l->reasm_buf);
1005 kfree_skb(l->reasm_tnlmsg);
1006 kfree_skb(l->failover_reasm_skb);
1007 l->reasm_buf = NULL;
1008 l->reasm_tnlmsg = NULL;
1009 l->failover_reasm_skb = NULL;
1010 l->rcv_unacked = 0;
1011 l->snd_nxt = 1;
1012 l->rcv_nxt = 1;
1013 l->snd_nxt_state = 1;
1014 l->rcv_nxt_state = 1;
1015 l->acked = 0;
1016 l->last_gap = 0;
1017 kfree(l->last_ga);
1018 l->last_ga = NULL;
1019 l->silent_intv_cnt = 0;
1020 l->rst_cnt = 0;
1021 l->bc_peer_is_up = false;
1022 memset(&l->mon_state, 0, sizeof(l->mon_state));
1023 tipc_link_reset_stats(l);
1024}
1025
1026/**
1027 * tipc_link_xmit(): enqueue buffer list according to queue situation
1028 * @l: link to use
1029 * @list: chain of buffers containing message
1030 * @xmitq: returned list of packets to be sent by caller
1031 *
1032 * Consumes the buffer chain.
1033 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1034 * Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
1035 */
1036int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1037 struct sk_buff_head *xmitq)
1038{
1039 struct sk_buff_head *backlogq = &l->backlogq;
1040 struct sk_buff_head *transmq = &l->transmq;
1041 struct sk_buff *skb, *_skb;
1042 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1043 u16 ack = l->rcv_nxt - 1;
1044 u16 seqno = l->snd_nxt;
1045 int pkt_cnt = skb_queue_len(list);
1046 unsigned int mss = tipc_link_mss(l);
1047 unsigned int cwin = l->window;
1048 unsigned int mtu = l->mtu;
1049 struct tipc_msg *hdr;
1050 bool new_bundle;
1051 int rc = 0;
1052 int imp;
1053
1054 if (pkt_cnt <= 0)
1055 return 0;
1056
1057 hdr = buf_msg(skb_peek(list));
1058 if (unlikely(msg_size(hdr) > mtu)) {
1059 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1060 skb_queue_len(list), msg_user(hdr),
1061 msg_type(hdr), msg_size(hdr), mtu);
1062 __skb_queue_purge(list);
1063 return -EMSGSIZE;
1064 }
1065
1066 imp = msg_importance(hdr);
1067 /* Allow oversubscription of one data msg per source at congestion */
1068 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1069 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1070 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1071 return -ENOBUFS;
1072 }
1073 rc = link_schedule_user(l, hdr);
1074 }
1075
1076 if (pkt_cnt > 1) {
1077 l->stats.sent_fragmented++;
1078 l->stats.sent_fragments += pkt_cnt;
1079 }
1080
1081 /* Prepare each packet for sending, and add to relevant queue: */
1082 while ((skb = __skb_dequeue(list))) {
1083 if (likely(skb_queue_len(transmq) < cwin)) {
1084 hdr = buf_msg(skb);
1085 msg_set_seqno(hdr, seqno);
1086 msg_set_ack(hdr, ack);
1087 msg_set_bcast_ack(hdr, bc_ack);
1088 _skb = skb_clone(skb, GFP_ATOMIC);
1089 if (!_skb) {
1090 kfree_skb(skb);
1091 __skb_queue_purge(list);
1092 return -ENOBUFS;
1093 }
1094 __skb_queue_tail(transmq, skb);
1095 tipc_link_set_skb_retransmit_time(skb, l);
1096 __skb_queue_tail(xmitq, _skb);
1097 TIPC_SKB_CB(skb)->ackers = l->ackers;
1098 l->rcv_unacked = 0;
1099 l->stats.sent_pkts++;
1100 seqno++;
1101 continue;
1102 }
1103 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1104 mss, l->addr, &new_bundle)) {
1105 if (skb) {
1106 /* Keep a ref. to the skb for next try */
1107 l->backlog[imp].target_bskb = skb;
1108 l->backlog[imp].len++;
1109 __skb_queue_tail(backlogq, skb);
1110 } else {
1111 if (new_bundle) {
1112 l->stats.sent_bundles++;
1113 l->stats.sent_bundled++;
1114 }
1115 l->stats.sent_bundled++;
1116 }
1117 continue;
1118 }
1119 l->backlog[imp].target_bskb = NULL;
1120 l->backlog[imp].len += (1 + skb_queue_len(list));
1121 __skb_queue_tail(backlogq, skb);
1122 skb_queue_splice_tail_init(list, backlogq);
1123 }
1124 l->snd_nxt = seqno;
1125 return rc;
1126}
1127
1128static void tipc_link_update_cwin(struct tipc_link *l, int released,
1129 bool retransmitted)
1130{
1131 int bklog_len = skb_queue_len(&l->backlogq);
1132 struct sk_buff_head *txq = &l->transmq;
1133 int txq_len = skb_queue_len(txq);
1134 u16 cwin = l->window;
1135
1136 /* Enter fast recovery */
1137 if (unlikely(retransmitted)) {
1138 l->ssthresh = max_t(u16, l->window / 2, 300);
1139 l->window = min_t(u16, l->ssthresh, l->window);
1140 return;
1141 }
1142 /* Enter slow start */
1143 if (unlikely(!released)) {
1144 l->ssthresh = max_t(u16, l->window / 2, 300);
1145 l->window = l->min_win;
1146 return;
1147 }
1148 /* Don't increase window if no pressure on the transmit queue */
1149 if (txq_len + bklog_len < cwin)
1150 return;
1151
1152 /* Don't increase window if there are holes the transmit queue */
1153 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1154 return;
1155
1156 l->cong_acks += released;
1157
1158 /* Slow start */
1159 if (cwin <= l->ssthresh) {
1160 l->window = min_t(u16, cwin + released, l->max_win);
1161 return;
1162 }
1163 /* Congestion avoidance */
1164 if (l->cong_acks < cwin)
1165 return;
1166 l->window = min_t(u16, ++cwin, l->max_win);
1167 l->cong_acks = 0;
1168}
1169
1170static void tipc_link_advance_backlog(struct tipc_link *l,
1171 struct sk_buff_head *xmitq)
1172{
1173 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1174 struct sk_buff_head *txq = &l->transmq;
1175 struct sk_buff *skb, *_skb;
1176 u16 ack = l->rcv_nxt - 1;
1177 u16 seqno = l->snd_nxt;
1178 struct tipc_msg *hdr;
1179 u16 cwin = l->window;
1180 u32 imp;
1181
1182 while (skb_queue_len(txq) < cwin) {
1183 skb = skb_peek(&l->backlogq);
1184 if (!skb)
1185 break;
1186 _skb = skb_clone(skb, GFP_ATOMIC);
1187 if (!_skb)
1188 break;
1189 __skb_dequeue(&l->backlogq);
1190 hdr = buf_msg(skb);
1191 imp = msg_importance(hdr);
1192 l->backlog[imp].len--;
1193 if (unlikely(skb == l->backlog[imp].target_bskb))
1194 l->backlog[imp].target_bskb = NULL;
1195 __skb_queue_tail(&l->transmq, skb);
1196 tipc_link_set_skb_retransmit_time(skb, l);
1197
1198 __skb_queue_tail(xmitq, _skb);
1199 TIPC_SKB_CB(skb)->ackers = l->ackers;
1200 msg_set_seqno(hdr, seqno);
1201 msg_set_ack(hdr, ack);
1202 msg_set_bcast_ack(hdr, bc_ack);
1203 l->rcv_unacked = 0;
1204 l->stats.sent_pkts++;
1205 seqno++;
1206 }
1207 l->snd_nxt = seqno;
1208}
1209
1210/**
1211 * link_retransmit_failure() - Detect repeated retransmit failures
1212 * @l: tipc link sender
1213 * @r: tipc link receiver (= l in case of unicast)
1214 * @rc: returned code
1215 *
1216 * Return: true if the repeated retransmit failures happens, otherwise
1217 * false
1218 */
1219static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1220 int *rc)
1221{
1222 struct sk_buff *skb = skb_peek(&l->transmq);
1223 struct tipc_msg *hdr;
1224
1225 if (!skb)
1226 return false;
1227
1228 if (!TIPC_SKB_CB(skb)->retr_cnt)
1229 return false;
1230
1231 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1232 msecs_to_jiffies(r->tolerance * 10)))
1233 return false;
1234
1235 hdr = buf_msg(skb);
1236 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1237 return false;
1238
1239 pr_warn("Retransmission failure on link <%s>\n", l->name);
1240 link_print(l, "State of link ");
1241 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1242 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1243 pr_info("sqno %u, prev: %x, dest: %x\n",
1244 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1245 pr_info("retr_stamp %d, retr_cnt %d\n",
1246 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1247 TIPC_SKB_CB(skb)->retr_cnt);
1248
1249 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1250 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1251 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1252
1253 if (link_is_bc_sndlink(l)) {
1254 r->state = LINK_RESET;
1255 *rc |= TIPC_LINK_DOWN_EVT;
1256 } else {
1257 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1258 }
1259
1260 return true;
1261}
1262
1263/* tipc_data_input - deliver data and name distr msgs to upper layer
1264 *
1265 * Consumes buffer if message is of right type
1266 * Node lock must be held
1267 */
1268static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1269 struct sk_buff_head *inputq)
1270{
1271 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1272 struct tipc_msg *hdr = buf_msg(skb);
1273
1274 switch (msg_user(hdr)) {
1275 case TIPC_LOW_IMPORTANCE:
1276 case TIPC_MEDIUM_IMPORTANCE:
1277 case TIPC_HIGH_IMPORTANCE:
1278 case TIPC_CRITICAL_IMPORTANCE:
1279 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1280 skb_queue_tail(mc_inputq, skb);
1281 return true;
1282 }
1283 fallthrough;
1284 case CONN_MANAGER:
1285 skb_queue_tail(inputq, skb);
1286 return true;
1287 case GROUP_PROTOCOL:
1288 skb_queue_tail(mc_inputq, skb);
1289 return true;
1290 case NAME_DISTRIBUTOR:
1291 l->bc_rcvlink->state = LINK_ESTABLISHED;
1292 skb_queue_tail(l->namedq, skb);
1293 return true;
1294 case MSG_BUNDLER:
1295 case TUNNEL_PROTOCOL:
1296 case MSG_FRAGMENTER:
1297 case BCAST_PROTOCOL:
1298 return false;
1299#ifdef CONFIG_TIPC_CRYPTO
1300 case MSG_CRYPTO:
1301 tipc_crypto_msg_rcv(l->net, skb);
1302 return true;
1303#endif
1304 default:
1305 pr_warn("Dropping received illegal msg type\n");
1306 kfree_skb(skb);
1307 return true;
1308 }
1309}
1310
1311/* tipc_link_input - process packet that has passed link protocol check
1312 *
1313 * Consumes buffer
1314 */
1315static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1316 struct sk_buff_head *inputq,
1317 struct sk_buff **reasm_skb)
1318{
1319 struct tipc_msg *hdr = buf_msg(skb);
1320 struct sk_buff *iskb;
1321 struct sk_buff_head tmpq;
1322 int usr = msg_user(hdr);
1323 int pos = 0;
1324
1325 if (usr == MSG_BUNDLER) {
1326 skb_queue_head_init(&tmpq);
1327 l->stats.recv_bundles++;
1328 l->stats.recv_bundled += msg_msgcnt(hdr);
1329 while (tipc_msg_extract(skb, &iskb, &pos))
1330 tipc_data_input(l, iskb, &tmpq);
1331 tipc_skb_queue_splice_tail(&tmpq, inputq);
1332 return 0;
1333 } else if (usr == MSG_FRAGMENTER) {
1334 l->stats.recv_fragments++;
1335 if (tipc_buf_append(reasm_skb, &skb)) {
1336 l->stats.recv_fragmented++;
1337 tipc_data_input(l, skb, inputq);
1338 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1339 pr_warn_ratelimited("Unable to build fragment list\n");
1340 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1341 }
1342 return 0;
1343 } else if (usr == BCAST_PROTOCOL) {
1344 tipc_bcast_lock(l->net);
1345 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1346 tipc_bcast_unlock(l->net);
1347 }
1348
1349 kfree_skb(skb);
1350 return 0;
1351}
1352
1353/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1354 * inner message along with the ones in the old link's
1355 * deferdq
1356 * @l: tunnel link
1357 * @skb: TUNNEL_PROTOCOL message
1358 * @inputq: queue to put messages ready for delivery
1359 */
1360static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1361 struct sk_buff_head *inputq)
1362{
1363 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1364 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1365 struct sk_buff_head *fdefq = &l->failover_deferdq;
1366 struct tipc_msg *hdr = buf_msg(skb);
1367 struct sk_buff *iskb;
1368 int ipos = 0;
1369 int rc = 0;
1370 u16 seqno;
1371
1372 if (msg_type(hdr) == SYNCH_MSG) {
1373 kfree_skb(skb);
1374 return 0;
1375 }
1376
1377 /* Not a fragment? */
1378 if (likely(!msg_nof_fragms(hdr))) {
1379 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1380 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1381 skb_queue_len(fdefq));
1382 return 0;
1383 }
1384 kfree_skb(skb);
1385 } else {
1386 /* Set fragment type for buf_append */
1387 if (msg_fragm_no(hdr) == 1)
1388 msg_set_type(hdr, FIRST_FRAGMENT);
1389 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1390 msg_set_type(hdr, FRAGMENT);
1391 else
1392 msg_set_type(hdr, LAST_FRAGMENT);
1393
1394 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1395 /* Successful but non-complete reassembly? */
1396 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1397 return 0;
1398 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1399 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1400 }
1401 iskb = skb;
1402 }
1403
1404 do {
1405 seqno = buf_seqno(iskb);
1406 if (unlikely(less(seqno, l->drop_point))) {
1407 kfree_skb(iskb);
1408 continue;
1409 }
1410 if (unlikely(seqno != l->drop_point)) {
1411 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1412 continue;
1413 }
1414
1415 l->drop_point++;
1416 if (!tipc_data_input(l, iskb, inputq))
1417 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1418 if (unlikely(rc))
1419 break;
1420 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1421
1422 return rc;
1423}
1424
1425/**
1426 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1427 * @ga: returned pointer to the Gap ACK blocks if any
1428 * @l: the tipc link
1429 * @hdr: the PROTOCOL/STATE_MSG header
1430 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1431 *
1432 * Return: the total Gap ACK blocks size
1433 */
1434u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1435 struct tipc_msg *hdr, bool uc)
1436{
1437 struct tipc_gap_ack_blks *p;
1438 u16 sz = 0;
1439
1440 /* Does peer support the Gap ACK blocks feature? */
1441 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1442 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1443 sz = ntohs(p->len);
1444 /* Sanity check */
1445 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1446 /* Good, check if the desired type exists */
1447 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1448 goto ok;
1449 /* Backward compatible: peer might not support bc, but uc? */
1450 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1451 if (p->ugack_cnt) {
1452 p->bgack_cnt = 0;
1453 goto ok;
1454 }
1455 }
1456 }
1457 /* Other cases: ignore! */
1458 p = NULL;
1459
1460ok:
1461 *ga = p;
1462 return sz;
1463}
1464
1465static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1466 struct tipc_link *l, u8 start_index)
1467{
1468 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1469 struct sk_buff *skb = skb_peek(&l->deferdq);
1470 u16 expect, seqno = 0;
1471 u8 n = 0;
1472
1473 if (!skb)
1474 return 0;
1475
1476 expect = buf_seqno(skb);
1477 skb_queue_walk(&l->deferdq, skb) {
1478 seqno = buf_seqno(skb);
1479 if (unlikely(more(seqno, expect))) {
1480 gacks[n].ack = htons(expect - 1);
1481 gacks[n].gap = htons(seqno - expect);
1482 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1483 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1484 l->name, n,
1485 skb_queue_len(&l->deferdq));
1486 return n;
1487 }
1488 } else if (unlikely(less(seqno, expect))) {
1489 pr_warn("Unexpected skb in deferdq!\n");
1490 continue;
1491 }
1492 expect = seqno + 1;
1493 }
1494
1495 /* last block */
1496 gacks[n].ack = htons(seqno);
1497 gacks[n].gap = 0;
1498 n++;
1499 return n;
1500}
1501
1502/* tipc_build_gap_ack_blks - build Gap ACK blocks
1503 * @l: tipc unicast link
1504 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1505 *
1506 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1507 * links of a certain peer, the buffer after built has the network data format
1508 * as found at the struct tipc_gap_ack_blks definition.
1509 *
1510 * returns the actual allocated memory size
1511 */
1512static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1513{
1514 struct tipc_link *bcl = l->bc_rcvlink;
1515 struct tipc_gap_ack_blks *ga;
1516 u16 len;
1517
1518 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1519
1520 /* Start with broadcast link first */
1521 tipc_bcast_lock(bcl->net);
1522 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1523 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1524 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1525 tipc_bcast_unlock(bcl->net);
1526
1527 /* Now for unicast link, but an explicit NACK only (???) */
1528 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1529 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1530
1531 /* Total len */
1532 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1533 ga->len = htons(len);
1534 return len;
1535}
1536
1537/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1538 * acked packets, also doing retransmissions if
1539 * gaps found
1540 * @l: tipc link with transmq queue to be advanced
1541 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1542 * @acked: seqno of last packet acked by peer without any gaps before
1543 * @gap: # of gap packets
1544 * @ga: buffer pointer to Gap ACK blocks from peer
1545 * @xmitq: queue for accumulating the retransmitted packets if any
1546 * @retransmitted: returned boolean value if a retransmission is really issued
1547 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1548 * happens (- unlikely case)
1549 *
1550 * Return: the number of packets released from the link transmq
1551 */
1552static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1553 u16 acked, u16 gap,
1554 struct tipc_gap_ack_blks *ga,
1555 struct sk_buff_head *xmitq,
1556 bool *retransmitted, int *rc)
1557{
1558 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1559 struct tipc_gap_ack *gacks = NULL;
1560 struct sk_buff *skb, *_skb, *tmp;
1561 struct tipc_msg *hdr;
1562 u32 qlen = skb_queue_len(&l->transmq);
1563 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1564 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1565 u16 ack = l->rcv_nxt - 1;
1566 u16 seqno, n = 0;
1567 u16 end = r->acked, start = end, offset = r->last_gap;
1568 u16 si = (last_ga) ? last_ga->start_index : 0;
1569 bool is_uc = !link_is_bc_sndlink(l);
1570 bool bc_has_acked = false;
1571
1572 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1573
1574 /* Determine Gap ACK blocks if any for the particular link */
1575 if (ga && is_uc) {
1576 /* Get the Gap ACKs, uc part */
1577 gack_cnt = ga->ugack_cnt;
1578 gacks = &ga->gacks[ga->bgack_cnt];
1579 } else if (ga) {
1580 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1581 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1582 GFP_ATOMIC);
1583 if (likely(this_ga)) {
1584 this_ga->start_index = 0;
1585 /* Start with the bc Gap ACKs */
1586 gack_cnt = this_ga->bgack_cnt;
1587 gacks = &this_ga->gacks[0];
1588 } else {
1589 /* Hmm, we can get in trouble..., simply ignore it */
1590 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1591 }
1592 }
1593
1594 /* Advance the link transmq */
1595 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1596 seqno = buf_seqno(skb);
1597
1598next_gap_ack:
1599 if (less_eq(seqno, nacked)) {
1600 if (is_uc)
1601 goto release;
1602 /* Skip packets peer has already acked */
1603 if (!more(seqno, r->acked))
1604 continue;
1605 /* Get the next of last Gap ACK blocks */
1606 while (more(seqno, end)) {
1607 if (!last_ga || si >= last_ga->bgack_cnt)
1608 break;
1609 start = end + offset + 1;
1610 end = ntohs(last_ga->gacks[si].ack);
1611 offset = ntohs(last_ga->gacks[si].gap);
1612 si++;
1613 WARN_ONCE(more(start, end) ||
1614 (!offset &&
1615 si < last_ga->bgack_cnt) ||
1616 si > MAX_GAP_ACK_BLKS,
1617 "Corrupted Gap ACK: %d %d %d %d %d\n",
1618 start, end, offset, si,
1619 last_ga->bgack_cnt);
1620 }
1621 /* Check against the last Gap ACK block */
1622 if (in_range(seqno, start, end))
1623 continue;
1624 /* Update/release the packet peer is acking */
1625 bc_has_acked = true;
1626 if (--TIPC_SKB_CB(skb)->ackers)
1627 continue;
1628release:
1629 /* release skb */
1630 __skb_unlink(skb, &l->transmq);
1631 kfree_skb(skb);
1632 } else if (less_eq(seqno, nacked + ngap)) {
1633 /* First gap: check if repeated retrans failures? */
1634 if (unlikely(seqno == acked + 1 &&
1635 link_retransmit_failure(l, r, rc))) {
1636 /* Ignore this bc Gap ACKs if any */
1637 kfree(this_ga);
1638 this_ga = NULL;
1639 break;
1640 }
1641 /* retransmit skb if unrestricted*/
1642 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1643 continue;
1644 tipc_link_set_skb_retransmit_time(skb, l);
1645 _skb = pskb_copy(skb, GFP_ATOMIC);
1646 if (!_skb)
1647 continue;
1648 hdr = buf_msg(_skb);
1649 msg_set_ack(hdr, ack);
1650 msg_set_bcast_ack(hdr, bc_ack);
1651 _skb->priority = TC_PRIO_CONTROL;
1652 __skb_queue_tail(xmitq, _skb);
1653 l->stats.retransmitted++;
1654 if (!is_uc)
1655 r->stats.retransmitted++;
1656 *retransmitted = true;
1657 /* Increase actual retrans counter & mark first time */
1658 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1659 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1660 } else {
1661 /* retry with Gap ACK blocks if any */
1662 if (n >= gack_cnt)
1663 break;
1664 nacked = ntohs(gacks[n].ack);
1665 ngap = ntohs(gacks[n].gap);
1666 n++;
1667 goto next_gap_ack;
1668 }
1669 }
1670
1671 /* Renew last Gap ACK blocks for bc if needed */
1672 if (bc_has_acked) {
1673 if (this_ga) {
1674 kfree(last_ga);
1675 r->last_ga = this_ga;
1676 r->last_gap = gap;
1677 } else if (last_ga) {
1678 if (less(acked, start)) {
1679 si--;
1680 offset = start - acked - 1;
1681 } else if (less(acked, end)) {
1682 acked = end;
1683 }
1684 if (si < last_ga->bgack_cnt) {
1685 last_ga->start_index = si;
1686 r->last_gap = offset;
1687 } else {
1688 kfree(last_ga);
1689 r->last_ga = NULL;
1690 r->last_gap = 0;
1691 }
1692 } else {
1693 r->last_gap = 0;
1694 }
1695 r->acked = acked;
1696 } else {
1697 kfree(this_ga);
1698 }
1699
1700 return qlen - skb_queue_len(&l->transmq);
1701}
1702
1703/* tipc_link_build_state_msg: prepare link state message for transmission
1704 *
1705 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1706 * risk of ack storms towards the sender
1707 */
1708int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1709{
1710 if (!l)
1711 return 0;
1712
1713 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1714 if (link_is_bc_rcvlink(l)) {
1715 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1716 return 0;
1717 l->rcv_unacked = 0;
1718
1719 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1720 l->snd_nxt = l->rcv_nxt;
1721 return TIPC_LINK_SND_STATE;
1722 }
1723 /* Unicast ACK */
1724 l->rcv_unacked = 0;
1725 l->stats.sent_acks++;
1726 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1727 return 0;
1728}
1729
1730/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1731 */
1732void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1733{
1734 int mtyp = RESET_MSG;
1735 struct sk_buff *skb;
1736
1737 if (l->state == LINK_ESTABLISHING)
1738 mtyp = ACTIVATE_MSG;
1739
1740 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1741
1742 /* Inform peer that this endpoint is going down if applicable */
1743 skb = skb_peek_tail(xmitq);
1744 if (skb && (l->state == LINK_RESET))
1745 msg_set_peer_stopping(buf_msg(skb), 1);
1746}
1747
1748/* tipc_link_build_nack_msg: prepare link nack message for transmission
1749 * Note that sending of broadcast NACK is coordinated among nodes, to
1750 * reduce the risk of NACK storms towards the sender
1751 */
1752static int tipc_link_build_nack_msg(struct tipc_link *l,
1753 struct sk_buff_head *xmitq)
1754{
1755 u32 def_cnt = ++l->stats.deferred_recv;
1756 struct sk_buff_head *dfq = &l->deferdq;
1757 u32 defq_len = skb_queue_len(dfq);
1758 int match1, match2;
1759
1760 if (link_is_bc_rcvlink(l)) {
1761 match1 = def_cnt & 0xf;
1762 match2 = tipc_own_addr(l->net) & 0xf;
1763 if (match1 == match2)
1764 return TIPC_LINK_SND_STATE;
1765 return 0;
1766 }
1767
1768 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1769 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1770
1771 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1772 rcvgap, 0, 0, xmitq);
1773 }
1774 return 0;
1775}
1776
1777/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1778 * @l: the link that should handle the message
1779 * @skb: TIPC packet
1780 * @xmitq: queue to place packets to be sent after this call
1781 */
1782int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1783 struct sk_buff_head *xmitq)
1784{
1785 struct sk_buff_head *defq = &l->deferdq;
1786 struct tipc_msg *hdr = buf_msg(skb);
1787 u16 seqno, rcv_nxt, win_lim;
1788 int released = 0;
1789 int rc = 0;
1790
1791 /* Verify and update link state */
1792 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1793 return tipc_link_proto_rcv(l, skb, xmitq);
1794
1795 /* Don't send probe at next timeout expiration */
1796 l->silent_intv_cnt = 0;
1797
1798 do {
1799 hdr = buf_msg(skb);
1800 seqno = msg_seqno(hdr);
1801 rcv_nxt = l->rcv_nxt;
1802 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1803
1804 if (unlikely(!link_is_up(l))) {
1805 if (l->state == LINK_ESTABLISHING)
1806 rc = TIPC_LINK_UP_EVT;
1807 kfree_skb(skb);
1808 break;
1809 }
1810
1811 /* Drop if outside receive window */
1812 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1813 l->stats.duplicates++;
1814 kfree_skb(skb);
1815 break;
1816 }
1817 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1818 NULL, NULL, NULL, NULL);
1819
1820 /* Defer delivery if sequence gap */
1821 if (unlikely(seqno != rcv_nxt)) {
1822 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1823 l->stats.duplicates++;
1824 rc |= tipc_link_build_nack_msg(l, xmitq);
1825 break;
1826 }
1827
1828 /* Deliver packet */
1829 l->rcv_nxt++;
1830 l->stats.recv_pkts++;
1831
1832 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1833 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1834 else if (!tipc_data_input(l, skb, l->inputq))
1835 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1836 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1837 rc |= tipc_link_build_state_msg(l, xmitq);
1838 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1839 break;
1840 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1841
1842 /* Forward queues and wake up waiting users */
1843 if (released) {
1844 tipc_link_update_cwin(l, released, 0);
1845 tipc_link_advance_backlog(l, xmitq);
1846 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1847 link_prepare_wakeup(l);
1848 }
1849 return rc;
1850}
1851
1852static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1853 bool probe_reply, u16 rcvgap,
1854 int tolerance, int priority,
1855 struct sk_buff_head *xmitq)
1856{
1857 struct tipc_mon_state *mstate = &l->mon_state;
1858 struct sk_buff_head *dfq = &l->deferdq;
1859 struct tipc_link *bcl = l->bc_rcvlink;
1860 struct tipc_msg *hdr;
1861 struct sk_buff *skb;
1862 bool node_up = link_is_up(bcl);
1863 u16 glen = 0, bc_rcvgap = 0;
1864 int dlen = 0;
1865 void *data;
1866
1867 /* Don't send protocol message during reset or link failover */
1868 if (tipc_link_is_blocked(l))
1869 return;
1870
1871 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1872 return;
1873
1874 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1875 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1876
1877 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1878 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1879 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1880 if (!skb)
1881 return;
1882
1883 hdr = buf_msg(skb);
1884 data = msg_data(hdr);
1885 msg_set_session(hdr, l->session);
1886 msg_set_bearer_id(hdr, l->bearer_id);
1887 msg_set_net_plane(hdr, l->net_plane);
1888 msg_set_next_sent(hdr, l->snd_nxt);
1889 msg_set_ack(hdr, l->rcv_nxt - 1);
1890 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1891 msg_set_bc_ack_invalid(hdr, !node_up);
1892 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1893 msg_set_link_tolerance(hdr, tolerance);
1894 msg_set_linkprio(hdr, priority);
1895 msg_set_redundant_link(hdr, node_up);
1896 msg_set_seq_gap(hdr, 0);
1897 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1898
1899 if (mtyp == STATE_MSG) {
1900 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1901 msg_set_seqno(hdr, l->snd_nxt_state++);
1902 msg_set_seq_gap(hdr, rcvgap);
1903 bc_rcvgap = link_bc_rcv_gap(bcl);
1904 msg_set_bc_gap(hdr, bc_rcvgap);
1905 msg_set_probe(hdr, probe);
1906 msg_set_is_keepalive(hdr, probe || probe_reply);
1907 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1908 glen = tipc_build_gap_ack_blks(l, hdr);
1909 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1910 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1911 skb_trim(skb, INT_H_SIZE + glen + dlen);
1912 l->stats.sent_states++;
1913 l->rcv_unacked = 0;
1914 } else {
1915 /* RESET_MSG or ACTIVATE_MSG */
1916 if (mtyp == ACTIVATE_MSG) {
1917 msg_set_dest_session_valid(hdr, 1);
1918 msg_set_dest_session(hdr, l->peer_session);
1919 }
1920 msg_set_max_pkt(hdr, l->advertised_mtu);
1921 strcpy(data, l->if_name);
1922 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1923 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1924 }
1925 if (probe)
1926 l->stats.sent_probes++;
1927 if (rcvgap)
1928 l->stats.sent_nacks++;
1929 if (bc_rcvgap)
1930 bcl->stats.sent_nacks++;
1931 skb->priority = TC_PRIO_CONTROL;
1932 __skb_queue_tail(xmitq, skb);
1933 trace_tipc_proto_build(skb, false, l->name);
1934}
1935
1936void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1937 struct sk_buff_head *xmitq)
1938{
1939 u32 onode = tipc_own_addr(l->net);
1940 struct tipc_msg *hdr, *ihdr;
1941 struct sk_buff_head tnlq;
1942 struct sk_buff *skb;
1943 u32 dnode = l->addr;
1944
1945 __skb_queue_head_init(&tnlq);
1946 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1947 INT_H_SIZE, BASIC_H_SIZE,
1948 dnode, onode, 0, 0, 0);
1949 if (!skb) {
1950 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1951 return;
1952 }
1953
1954 hdr = buf_msg(skb);
1955 msg_set_msgcnt(hdr, 1);
1956 msg_set_bearer_id(hdr, l->peer_bearer_id);
1957
1958 ihdr = (struct tipc_msg *)msg_data(hdr);
1959 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1960 BASIC_H_SIZE, dnode);
1961 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1962 __skb_queue_tail(&tnlq, skb);
1963 tipc_link_xmit(l, &tnlq, xmitq);
1964}
1965
1966/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1967 * with contents of the link's transmit and backlog queues.
1968 */
1969void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1970 int mtyp, struct sk_buff_head *xmitq)
1971{
1972 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1973 struct sk_buff *skb, *tnlskb;
1974 struct tipc_msg *hdr, tnlhdr;
1975 struct sk_buff_head *queue = &l->transmq;
1976 struct sk_buff_head tmpxq, tnlq, frags;
1977 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1978 bool pktcnt_need_update = false;
1979 u16 syncpt;
1980 int rc;
1981
1982 if (!tnl)
1983 return;
1984
1985 __skb_queue_head_init(&tnlq);
1986 /* Link Synching:
1987 * From now on, send only one single ("dummy") SYNCH message
1988 * to peer. The SYNCH message does not contain any data, just
1989 * a header conveying the synch point to the peer.
1990 */
1991 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1992 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1993 INT_H_SIZE, 0, l->addr,
1994 tipc_own_addr(l->net),
1995 0, 0, 0);
1996 if (!tnlskb) {
1997 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1998 link_co_err);
1999 return;
2000 }
2001
2002 hdr = buf_msg(tnlskb);
2003 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
2004 msg_set_syncpt(hdr, syncpt);
2005 msg_set_bearer_id(hdr, l->peer_bearer_id);
2006 __skb_queue_tail(&tnlq, tnlskb);
2007 tipc_link_xmit(tnl, &tnlq, xmitq);
2008 return;
2009 }
2010
2011 __skb_queue_head_init(&tmpxq);
2012 __skb_queue_head_init(&frags);
2013 /* At least one packet required for safe algorithm => add dummy */
2014 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
2015 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
2016 0, 0, TIPC_ERR_NO_PORT);
2017 if (!skb) {
2018 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2019 return;
2020 }
2021 __skb_queue_tail(&tnlq, skb);
2022 tipc_link_xmit(l, &tnlq, &tmpxq);
2023 __skb_queue_purge(&tmpxq);
2024
2025 /* Initialize reusable tunnel packet header */
2026 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2027 mtyp, INT_H_SIZE, l->addr);
2028 if (mtyp == SYNCH_MSG)
2029 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2030 else
2031 pktcnt = skb_queue_len(&l->transmq);
2032 pktcnt += skb_queue_len(&l->backlogq);
2033 msg_set_msgcnt(&tnlhdr, pktcnt);
2034 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2035tnl:
2036 /* Wrap each packet into a tunnel packet */
2037 skb_queue_walk(queue, skb) {
2038 hdr = buf_msg(skb);
2039 if (queue == &l->backlogq)
2040 msg_set_seqno(hdr, seqno++);
2041 pktlen = msg_size(hdr);
2042
2043 /* Tunnel link MTU is not large enough? This could be
2044 * due to:
2045 * 1) Link MTU has just changed or set differently;
2046 * 2) Or FAILOVER on the top of a SYNCH message
2047 *
2048 * The 2nd case should not happen if peer supports
2049 * TIPC_TUNNEL_ENHANCED
2050 */
2051 if (pktlen > tnl->mtu - INT_H_SIZE) {
2052 if (mtyp == FAILOVER_MSG &&
2053 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2054 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2055 &frags);
2056 if (rc) {
2057 pr_warn("%sunable to frag msg: rc %d\n",
2058 link_co_err, rc);
2059 return;
2060 }
2061 pktcnt += skb_queue_len(&frags) - 1;
2062 pktcnt_need_update = true;
2063 skb_queue_splice_tail_init(&frags, &tnlq);
2064 continue;
2065 }
2066 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2067 * => Just warn it and return!
2068 */
2069 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2070 link_co_err, msg_user(hdr),
2071 msg_type(hdr), msg_size(hdr));
2072 return;
2073 }
2074
2075 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2076 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2077 if (!tnlskb) {
2078 pr_warn("%sunable to send packet\n", link_co_err);
2079 return;
2080 }
2081 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2082 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2083 __skb_queue_tail(&tnlq, tnlskb);
2084 }
2085 if (queue != &l->backlogq) {
2086 queue = &l->backlogq;
2087 goto tnl;
2088 }
2089
2090 if (pktcnt_need_update)
2091 skb_queue_walk(&tnlq, skb) {
2092 hdr = buf_msg(skb);
2093 msg_set_msgcnt(hdr, pktcnt);
2094 }
2095
2096 tipc_link_xmit(tnl, &tnlq, xmitq);
2097
2098 if (mtyp == FAILOVER_MSG) {
2099 tnl->drop_point = l->rcv_nxt;
2100 tnl->failover_reasm_skb = l->reasm_buf;
2101 l->reasm_buf = NULL;
2102
2103 /* Failover the link's deferdq */
2104 if (unlikely(!skb_queue_empty(fdefq))) {
2105 pr_warn("Link failover deferdq not empty: %d!\n",
2106 skb_queue_len(fdefq));
2107 __skb_queue_purge(fdefq);
2108 }
2109 skb_queue_splice_init(&l->deferdq, fdefq);
2110 }
2111}
2112
2113/**
2114 * tipc_link_failover_prepare() - prepare tnl for link failover
2115 *
2116 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2117 * see the tipc_node_link_failover() for details
2118 *
2119 * @l: failover link
2120 * @tnl: tunnel link
2121 * @xmitq: queue for messages to be xmited
2122 */
2123void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2124 struct sk_buff_head *xmitq)
2125{
2126 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2127
2128 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2129
2130 /* This failover link endpoint was never established before,
2131 * so it has not received anything from peer.
2132 * Otherwise, it must be a normal failover situation or the
2133 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2134 * would have to start over from scratch instead.
2135 */
2136 tnl->drop_point = 1;
2137 tnl->failover_reasm_skb = NULL;
2138
2139 /* Initiate the link's failover deferdq */
2140 if (unlikely(!skb_queue_empty(fdefq))) {
2141 pr_warn("Link failover deferdq not empty: %d!\n",
2142 skb_queue_len(fdefq));
2143 __skb_queue_purge(fdefq);
2144 }
2145}
2146
2147/* tipc_link_validate_msg(): validate message against current link state
2148 * Returns true if message should be accepted, otherwise false
2149 */
2150bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2151{
2152 u16 curr_session = l->peer_session;
2153 u16 session = msg_session(hdr);
2154 int mtyp = msg_type(hdr);
2155
2156 if (msg_user(hdr) != LINK_PROTOCOL)
2157 return true;
2158
2159 switch (mtyp) {
2160 case RESET_MSG:
2161 if (!l->in_session)
2162 return true;
2163 /* Accept only RESET with new session number */
2164 return more(session, curr_session);
2165 case ACTIVATE_MSG:
2166 if (!l->in_session)
2167 return true;
2168 /* Accept only ACTIVATE with new or current session number */
2169 return !less(session, curr_session);
2170 case STATE_MSG:
2171 /* Accept only STATE with current session number */
2172 if (!l->in_session)
2173 return false;
2174 if (session != curr_session)
2175 return false;
2176 /* Extra sanity check */
2177 if (!link_is_up(l) && msg_ack(hdr))
2178 return false;
2179 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2180 return true;
2181 /* Accept only STATE with new sequence number */
2182 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2183 default:
2184 return false;
2185 }
2186}
2187
2188/* tipc_link_proto_rcv(): receive link level protocol message :
2189 * Note that network plane id propagates through the network, and may
2190 * change at any time. The node with lowest numerical id determines
2191 * network plane
2192 */
2193static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2194 struct sk_buff_head *xmitq)
2195{
2196 struct tipc_msg *hdr = buf_msg(skb);
2197 struct tipc_gap_ack_blks *ga = NULL;
2198 bool reply = msg_probe(hdr), retransmitted = false;
2199 u16 dlen = msg_data_sz(hdr), glen = 0;
2200 u16 peers_snd_nxt = msg_next_sent(hdr);
2201 u16 peers_tol = msg_link_tolerance(hdr);
2202 u16 peers_prio = msg_linkprio(hdr);
2203 u16 gap = msg_seq_gap(hdr);
2204 u16 ack = msg_ack(hdr);
2205 u16 rcv_nxt = l->rcv_nxt;
2206 u16 rcvgap = 0;
2207 int mtyp = msg_type(hdr);
2208 int rc = 0, released;
2209 char *if_name;
2210 void *data;
2211
2212 trace_tipc_proto_rcv(skb, false, l->name);
2213 if (tipc_link_is_blocked(l) || !xmitq)
2214 goto exit;
2215
2216 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2217 l->net_plane = msg_net_plane(hdr);
2218
2219 skb_linearize(skb);
2220 hdr = buf_msg(skb);
2221 data = msg_data(hdr);
2222
2223 if (!tipc_link_validate_msg(l, hdr)) {
2224 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2225 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2226 goto exit;
2227 }
2228
2229 switch (mtyp) {
2230 case RESET_MSG:
2231 case ACTIVATE_MSG:
2232 /* Complete own link name with peer's interface name */
2233 if_name = strrchr(l->name, ':') + 1;
2234 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2235 break;
2236 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2237 break;
2238 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2239
2240 /* Update own tolerance if peer indicates a non-zero value */
2241 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2242 l->tolerance = peers_tol;
2243 l->bc_rcvlink->tolerance = peers_tol;
2244 }
2245 /* Update own priority if peer's priority is higher */
2246 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2247 l->priority = peers_prio;
2248
2249 /* If peer is going down we want full re-establish cycle */
2250 if (msg_peer_stopping(hdr)) {
2251 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2252 break;
2253 }
2254
2255 /* If this endpoint was re-created while peer was ESTABLISHING
2256 * it doesn't know current session number. Force re-synch.
2257 */
2258 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2259 l->session != msg_dest_session(hdr)) {
2260 if (less(l->session, msg_dest_session(hdr)))
2261 l->session = msg_dest_session(hdr) + 1;
2262 break;
2263 }
2264
2265 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2266 if (mtyp == RESET_MSG || !link_is_up(l))
2267 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2268
2269 /* ACTIVATE_MSG takes up link if it was already locally reset */
2270 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2271 rc = TIPC_LINK_UP_EVT;
2272
2273 l->peer_session = msg_session(hdr);
2274 l->in_session = true;
2275 l->peer_bearer_id = msg_bearer_id(hdr);
2276 if (l->mtu > msg_max_pkt(hdr))
2277 l->mtu = msg_max_pkt(hdr);
2278 break;
2279
2280 case STATE_MSG:
2281 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2282
2283 /* Update own tolerance if peer indicates a non-zero value */
2284 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2285 l->tolerance = peers_tol;
2286 l->bc_rcvlink->tolerance = peers_tol;
2287 }
2288 /* Update own prio if peer indicates a different value */
2289 if ((peers_prio != l->priority) &&
2290 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2291 l->priority = peers_prio;
2292 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2293 }
2294
2295 l->silent_intv_cnt = 0;
2296 l->stats.recv_states++;
2297 if (msg_probe(hdr))
2298 l->stats.recv_probes++;
2299
2300 if (!link_is_up(l)) {
2301 if (l->state == LINK_ESTABLISHING)
2302 rc = TIPC_LINK_UP_EVT;
2303 break;
2304 }
2305
2306 /* Receive Gap ACK blocks from peer if any */
2307 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2308
2309 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2310 &l->mon_state, l->bearer_id);
2311
2312 /* Send NACK if peer has sent pkts we haven't received yet */
2313 if ((reply || msg_is_keepalive(hdr)) &&
2314 more(peers_snd_nxt, rcv_nxt) &&
2315 !tipc_link_is_synching(l) &&
2316 skb_queue_empty(&l->deferdq))
2317 rcvgap = peers_snd_nxt - l->rcv_nxt;
2318 if (rcvgap || reply)
2319 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2320 rcvgap, 0, 0, xmitq);
2321
2322 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2323 &retransmitted, &rc);
2324 if (gap)
2325 l->stats.recv_nacks++;
2326 if (released || retransmitted)
2327 tipc_link_update_cwin(l, released, retransmitted);
2328 if (released)
2329 tipc_link_advance_backlog(l, xmitq);
2330 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2331 link_prepare_wakeup(l);
2332 }
2333exit:
2334 kfree_skb(skb);
2335 return rc;
2336}
2337
2338/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2339 */
2340static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2341 u16 peers_snd_nxt,
2342 struct sk_buff_head *xmitq)
2343{
2344 struct sk_buff *skb;
2345 struct tipc_msg *hdr;
2346 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2347 u16 ack = l->rcv_nxt - 1;
2348 u16 gap_to = peers_snd_nxt - 1;
2349
2350 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2351 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2352 if (!skb)
2353 return false;
2354 hdr = buf_msg(skb);
2355 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2356 msg_set_bcast_ack(hdr, ack);
2357 msg_set_bcgap_after(hdr, ack);
2358 if (dfrd_skb)
2359 gap_to = buf_seqno(dfrd_skb) - 1;
2360 msg_set_bcgap_to(hdr, gap_to);
2361 msg_set_non_seq(hdr, bcast);
2362 __skb_queue_tail(xmitq, skb);
2363 return true;
2364}
2365
2366/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2367 *
2368 * Give a newly added peer node the sequence number where it should
2369 * start receiving and acking broadcast packets.
2370 */
2371static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2372 struct sk_buff_head *xmitq)
2373{
2374 struct sk_buff_head list;
2375
2376 __skb_queue_head_init(&list);
2377 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2378 return;
2379 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2380 tipc_link_xmit(l, &list, xmitq);
2381}
2382
2383/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2384 */
2385void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2386{
2387 int mtyp = msg_type(hdr);
2388 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2389
2390 if (link_is_up(l))
2391 return;
2392
2393 if (msg_user(hdr) == BCAST_PROTOCOL) {
2394 l->rcv_nxt = peers_snd_nxt;
2395 l->state = LINK_ESTABLISHED;
2396 return;
2397 }
2398
2399 if (l->peer_caps & TIPC_BCAST_SYNCH)
2400 return;
2401
2402 if (msg_peer_node_is_up(hdr))
2403 return;
2404
2405 /* Compatibility: accept older, less safe initial synch data */
2406 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2407 l->rcv_nxt = peers_snd_nxt;
2408}
2409
2410/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2411 */
2412int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2413 struct sk_buff_head *xmitq)
2414{
2415 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2416 int rc = 0;
2417
2418 if (!link_is_up(l))
2419 return rc;
2420
2421 if (!msg_peer_node_is_up(hdr))
2422 return rc;
2423
2424 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2425 if (msg_ack(hdr))
2426 l->bc_peer_is_up = true;
2427
2428 if (!l->bc_peer_is_up)
2429 return rc;
2430
2431 /* Ignore if peers_snd_nxt goes beyond receive window */
2432 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2433 return rc;
2434
2435 l->snd_nxt = peers_snd_nxt;
2436 if (link_bc_rcv_gap(l))
2437 rc |= TIPC_LINK_SND_STATE;
2438
2439 /* Return now if sender supports nack via STATE messages */
2440 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2441 return rc;
2442
2443 /* Otherwise, be backwards compatible */
2444
2445 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2446 l->nack_state = BC_NACK_SND_CONDITIONAL;
2447 return 0;
2448 }
2449
2450 /* Don't NACK if one was recently sent or peeked */
2451 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2452 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2453 return 0;
2454 }
2455
2456 /* Conditionally delay NACK sending until next synch rcv */
2457 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2458 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2459 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2460 return 0;
2461 }
2462
2463 /* Send NACK now but suppress next one */
2464 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2465 l->nack_state = BC_NACK_SND_SUPPRESS;
2466 return 0;
2467}
2468
2469int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2470 struct tipc_gap_ack_blks *ga,
2471 struct sk_buff_head *xmitq,
2472 struct sk_buff_head *retrq)
2473{
2474 struct tipc_link *l = r->bc_sndlink;
2475 bool unused = false;
2476 int rc = 0;
2477
2478 if (!link_is_up(r) || !r->bc_peer_is_up)
2479 return 0;
2480
2481 if (gap) {
2482 l->stats.recv_nacks++;
2483 r->stats.recv_nacks++;
2484 }
2485
2486 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2487 return 0;
2488
2489 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2490 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2491
2492 tipc_link_advance_backlog(l, xmitq);
2493 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2494 link_prepare_wakeup(l);
2495
2496 return rc;
2497}
2498
2499/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2500 * This function is here for backwards compatibility, since
2501 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2502 */
2503int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2504 struct sk_buff_head *xmitq)
2505{
2506 struct tipc_msg *hdr = buf_msg(skb);
2507 u32 dnode = msg_destnode(hdr);
2508 int mtyp = msg_type(hdr);
2509 u16 acked = msg_bcast_ack(hdr);
2510 u16 from = acked + 1;
2511 u16 to = msg_bcgap_to(hdr);
2512 u16 peers_snd_nxt = to + 1;
2513 int rc = 0;
2514
2515 kfree_skb(skb);
2516
2517 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2518 return 0;
2519
2520 if (mtyp != STATE_MSG)
2521 return 0;
2522
2523 if (dnode == tipc_own_addr(l->net)) {
2524 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2525 xmitq);
2526 l->stats.recv_nacks++;
2527 return rc;
2528 }
2529
2530 /* Msg for other node => suppress own NACK at next sync if applicable */
2531 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2532 l->nack_state = BC_NACK_SND_SUPPRESS;
2533
2534 return 0;
2535}
2536
2537void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2538{
2539 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2540
2541 l->min_win = min_win;
2542 l->ssthresh = max_win;
2543 l->max_win = max_win;
2544 l->window = min_win;
2545 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2546 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2547 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2548 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2549 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2550}
2551
2552/**
2553 * tipc_link_reset_stats - reset link statistics
2554 * @l: pointer to link
2555 */
2556void tipc_link_reset_stats(struct tipc_link *l)
2557{
2558 memset(&l->stats, 0, sizeof(l->stats));
2559}
2560
2561static void link_print(struct tipc_link *l, const char *str)
2562{
2563 struct sk_buff *hskb = skb_peek(&l->transmq);
2564 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2565 u16 tail = l->snd_nxt - 1;
2566
2567 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2568 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2569 skb_queue_len(&l->transmq), head, tail,
2570 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2571}
2572
2573/* Parse and validate nested (link) properties valid for media, bearer and link
2574 */
2575int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2576{
2577 int err;
2578
2579 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2580 tipc_nl_prop_policy, NULL);
2581 if (err)
2582 return err;
2583
2584 if (props[TIPC_NLA_PROP_PRIO]) {
2585 u32 prio;
2586
2587 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2588 if (prio > TIPC_MAX_LINK_PRI)
2589 return -EINVAL;
2590 }
2591
2592 if (props[TIPC_NLA_PROP_TOL]) {
2593 u32 tol;
2594
2595 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2596 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2597 return -EINVAL;
2598 }
2599
2600 if (props[TIPC_NLA_PROP_WIN]) {
2601 u32 max_win;
2602
2603 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2604 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2605 return -EINVAL;
2606 }
2607
2608 return 0;
2609}
2610
2611static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2612{
2613 int i;
2614 struct nlattr *stats;
2615
2616 struct nla_map {
2617 u32 key;
2618 u32 val;
2619 };
2620
2621 struct nla_map map[] = {
2622 {TIPC_NLA_STATS_RX_INFO, 0},
2623 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2624 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2625 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2626 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2627 {TIPC_NLA_STATS_TX_INFO, 0},
2628 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2629 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2630 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2631 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2632 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2633 s->msg_length_counts : 1},
2634 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2635 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2636 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2637 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2638 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2639 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2640 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2641 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2642 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2643 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2644 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2645 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2646 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2647 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2648 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2649 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2650 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2651 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2652 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2653 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2654 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2655 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2656 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2657 };
2658
2659 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2660 if (!stats)
2661 return -EMSGSIZE;
2662
2663 for (i = 0; i < ARRAY_SIZE(map); i++)
2664 if (nla_put_u32(skb, map[i].key, map[i].val))
2665 goto msg_full;
2666
2667 nla_nest_end(skb, stats);
2668
2669 return 0;
2670msg_full:
2671 nla_nest_cancel(skb, stats);
2672
2673 return -EMSGSIZE;
2674}
2675
2676/* Caller should hold appropriate locks to protect the link */
2677int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2678 struct tipc_link *link, int nlflags)
2679{
2680 u32 self = tipc_own_addr(net);
2681 struct nlattr *attrs;
2682 struct nlattr *prop;
2683 void *hdr;
2684 int err;
2685
2686 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2687 nlflags, TIPC_NL_LINK_GET);
2688 if (!hdr)
2689 return -EMSGSIZE;
2690
2691 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2692 if (!attrs)
2693 goto msg_full;
2694
2695 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2696 goto attr_msg_full;
2697 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2698 goto attr_msg_full;
2699 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2700 goto attr_msg_full;
2701 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2702 goto attr_msg_full;
2703 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2704 goto attr_msg_full;
2705
2706 if (tipc_link_is_up(link))
2707 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2708 goto attr_msg_full;
2709 if (link->active)
2710 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2711 goto attr_msg_full;
2712
2713 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2714 if (!prop)
2715 goto attr_msg_full;
2716 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2717 goto prop_msg_full;
2718 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2719 goto prop_msg_full;
2720 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2721 link->window))
2722 goto prop_msg_full;
2723 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2724 goto prop_msg_full;
2725 nla_nest_end(msg->skb, prop);
2726
2727 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2728 if (err)
2729 goto attr_msg_full;
2730
2731 nla_nest_end(msg->skb, attrs);
2732 genlmsg_end(msg->skb, hdr);
2733
2734 return 0;
2735
2736prop_msg_full:
2737 nla_nest_cancel(msg->skb, prop);
2738attr_msg_full:
2739 nla_nest_cancel(msg->skb, attrs);
2740msg_full:
2741 genlmsg_cancel(msg->skb, hdr);
2742
2743 return -EMSGSIZE;
2744}
2745
2746static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2747 struct tipc_stats *stats)
2748{
2749 int i;
2750 struct nlattr *nest;
2751
2752 struct nla_map {
2753 __u32 key;
2754 __u32 val;
2755 };
2756
2757 struct nla_map map[] = {
2758 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2759 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2760 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2761 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2762 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2763 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2764 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2765 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2766 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2767 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2768 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2769 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2770 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2771 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2772 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2773 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2774 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2775 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2776 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2777 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2778 };
2779
2780 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2781 if (!nest)
2782 return -EMSGSIZE;
2783
2784 for (i = 0; i < ARRAY_SIZE(map); i++)
2785 if (nla_put_u32(skb, map[i].key, map[i].val))
2786 goto msg_full;
2787
2788 nla_nest_end(skb, nest);
2789
2790 return 0;
2791msg_full:
2792 nla_nest_cancel(skb, nest);
2793
2794 return -EMSGSIZE;
2795}
2796
2797int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2798 struct tipc_link *bcl)
2799{
2800 int err;
2801 void *hdr;
2802 struct nlattr *attrs;
2803 struct nlattr *prop;
2804 u32 bc_mode = tipc_bcast_get_mode(net);
2805 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2806
2807 if (!bcl)
2808 return 0;
2809
2810 tipc_bcast_lock(net);
2811
2812 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2813 NLM_F_MULTI, TIPC_NL_LINK_GET);
2814 if (!hdr) {
2815 tipc_bcast_unlock(net);
2816 return -EMSGSIZE;
2817 }
2818
2819 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2820 if (!attrs)
2821 goto msg_full;
2822
2823 /* The broadcast link is always up */
2824 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2825 goto attr_msg_full;
2826
2827 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2828 goto attr_msg_full;
2829 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2830 goto attr_msg_full;
2831 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2832 goto attr_msg_full;
2833 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2834 goto attr_msg_full;
2835
2836 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2837 if (!prop)
2838 goto attr_msg_full;
2839 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2840 goto prop_msg_full;
2841 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2842 goto prop_msg_full;
2843 if (bc_mode & BCLINK_MODE_SEL)
2844 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2845 bc_ratio))
2846 goto prop_msg_full;
2847 nla_nest_end(msg->skb, prop);
2848
2849 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2850 if (err)
2851 goto attr_msg_full;
2852
2853 tipc_bcast_unlock(net);
2854 nla_nest_end(msg->skb, attrs);
2855 genlmsg_end(msg->skb, hdr);
2856
2857 return 0;
2858
2859prop_msg_full:
2860 nla_nest_cancel(msg->skb, prop);
2861attr_msg_full:
2862 nla_nest_cancel(msg->skb, attrs);
2863msg_full:
2864 tipc_bcast_unlock(net);
2865 genlmsg_cancel(msg->skb, hdr);
2866
2867 return -EMSGSIZE;
2868}
2869
2870void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2871 struct sk_buff_head *xmitq)
2872{
2873 l->tolerance = tol;
2874 if (l->bc_rcvlink)
2875 l->bc_rcvlink->tolerance = tol;
2876 if (link_is_up(l))
2877 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2878}
2879
2880void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2881 struct sk_buff_head *xmitq)
2882{
2883 l->priority = prio;
2884 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2885}
2886
2887void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2888{
2889 l->abort_limit = limit;
2890}
2891
2892/**
2893 * tipc_link_dump - dump TIPC link data
2894 * @l: tipc link to be dumped
2895 * @dqueues: bitmask to decide if any link queue to be dumped?
2896 * - TIPC_DUMP_NONE: don't dump link queues
2897 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2898 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2899 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2900 * - TIPC_DUMP_INPUTQ: dump link input queue
2901 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2902 * - TIPC_DUMP_ALL: dump all the link queues above
2903 * @buf: returned buffer of dump data in format
2904 */
2905int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2906{
2907 int i = 0;
2908 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2909 struct sk_buff_head *list;
2910 struct sk_buff *hskb, *tskb;
2911 u32 len;
2912
2913 if (!l) {
2914 i += scnprintf(buf, sz, "link data: (null)\n");
2915 return i;
2916 }
2917
2918 i += scnprintf(buf, sz, "link data: %x", l->addr);
2919 i += scnprintf(buf + i, sz - i, " %x", l->state);
2920 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2921 i += scnprintf(buf + i, sz - i, " %u", l->session);
2922 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2923 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2924 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2925 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2926 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2927 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2928 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2929 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2930 i += scnprintf(buf + i, sz - i, " %u", 0);
2931 i += scnprintf(buf + i, sz - i, " %u", 0);
2932 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2933
2934 list = &l->transmq;
2935 len = skb_queue_len(list);
2936 hskb = skb_peek(list);
2937 tskb = skb_peek_tail(list);
2938 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2939 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2940 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2941
2942 list = &l->deferdq;
2943 len = skb_queue_len(list);
2944 hskb = skb_peek(list);
2945 tskb = skb_peek_tail(list);
2946 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2947 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2948 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2949
2950 list = &l->backlogq;
2951 len = skb_queue_len(list);
2952 hskb = skb_peek(list);
2953 tskb = skb_peek_tail(list);
2954 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2955 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2956 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2957
2958 list = l->inputq;
2959 len = skb_queue_len(list);
2960 hskb = skb_peek(list);
2961 tskb = skb_peek_tail(list);
2962 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2963 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2964 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2965
2966 if (dqueues & TIPC_DUMP_TRANSMQ) {
2967 i += scnprintf(buf + i, sz - i, "transmq: ");
2968 i += tipc_list_dump(&l->transmq, false, buf + i);
2969 }
2970 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2971 i += scnprintf(buf + i, sz - i,
2972 "backlogq: <%u %u %u %u %u>, ",
2973 l->backlog[TIPC_LOW_IMPORTANCE].len,
2974 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2975 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2976 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2977 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2978 i += tipc_list_dump(&l->backlogq, false, buf + i);
2979 }
2980 if (dqueues & TIPC_DUMP_DEFERDQ) {
2981 i += scnprintf(buf + i, sz - i, "deferdq: ");
2982 i += tipc_list_dump(&l->deferdq, false, buf + i);
2983 }
2984 if (dqueues & TIPC_DUMP_INPUTQ) {
2985 i += scnprintf(buf + i, sz - i, "inputq: ");
2986 i += tipc_list_dump(l->inputq, false, buf + i);
2987 }
2988 if (dqueues & TIPC_DUMP_WAKEUP) {
2989 i += scnprintf(buf + i, sz - i, "wakeup: ");
2990 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2991 }
2992
2993 return i;
2994}
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
244/* Link FSM state checking routines
245 */
246static int link_is_up(struct tipc_link *l)
247{
248 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
249}
250
251static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
252 struct sk_buff_head *xmitq);
253static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
254 bool probe_reply, u16 rcvgap,
255 int tolerance, int priority,
256 struct sk_buff_head *xmitq);
257static void link_print(struct tipc_link *l, const char *str);
258static int tipc_link_build_nack_msg(struct tipc_link *l,
259 struct sk_buff_head *xmitq);
260static void tipc_link_build_bc_init_msg(struct tipc_link *l,
261 struct sk_buff_head *xmitq);
262static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
263 struct tipc_link *l, u8 start_index);
264static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
265static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
266 u16 acked, u16 gap,
267 struct tipc_gap_ack_blks *ga,
268 struct sk_buff_head *xmitq,
269 bool *retransmitted, int *rc);
270static void tipc_link_update_cwin(struct tipc_link *l, int released,
271 bool retransmitted);
272/*
273 * Simple non-static link routines (i.e. referenced outside this file)
274 */
275bool tipc_link_is_up(struct tipc_link *l)
276{
277 return link_is_up(l);
278}
279
280bool tipc_link_peer_is_down(struct tipc_link *l)
281{
282 return l->state == LINK_PEER_RESET;
283}
284
285bool tipc_link_is_reset(struct tipc_link *l)
286{
287 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
288}
289
290bool tipc_link_is_establishing(struct tipc_link *l)
291{
292 return l->state == LINK_ESTABLISHING;
293}
294
295bool tipc_link_is_synching(struct tipc_link *l)
296{
297 return l->state == LINK_SYNCHING;
298}
299
300bool tipc_link_is_failingover(struct tipc_link *l)
301{
302 return l->state == LINK_FAILINGOVER;
303}
304
305bool tipc_link_is_blocked(struct tipc_link *l)
306{
307 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
308}
309
310static bool link_is_bc_sndlink(struct tipc_link *l)
311{
312 return !l->bc_sndlink;
313}
314
315static bool link_is_bc_rcvlink(struct tipc_link *l)
316{
317 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
318}
319
320void tipc_link_set_active(struct tipc_link *l, bool active)
321{
322 l->active = active;
323}
324
325u32 tipc_link_id(struct tipc_link *l)
326{
327 return l->peer_bearer_id << 16 | l->bearer_id;
328}
329
330int tipc_link_min_win(struct tipc_link *l)
331{
332 return l->min_win;
333}
334
335int tipc_link_max_win(struct tipc_link *l)
336{
337 return l->max_win;
338}
339
340int tipc_link_prio(struct tipc_link *l)
341{
342 return l->priority;
343}
344
345unsigned long tipc_link_tolerance(struct tipc_link *l)
346{
347 return l->tolerance;
348}
349
350struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
351{
352 return l->inputq;
353}
354
355char tipc_link_plane(struct tipc_link *l)
356{
357 return l->net_plane;
358}
359
360struct net *tipc_link_net(struct tipc_link *l)
361{
362 return l->net;
363}
364
365void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
366{
367 l->peer_caps = capabilities;
368}
369
370void tipc_link_add_bc_peer(struct tipc_link *snd_l,
371 struct tipc_link *uc_l,
372 struct sk_buff_head *xmitq)
373{
374 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
375
376 snd_l->ackers++;
377 rcv_l->acked = snd_l->snd_nxt - 1;
378 snd_l->state = LINK_ESTABLISHED;
379 tipc_link_build_bc_init_msg(uc_l, xmitq);
380}
381
382void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
383 struct tipc_link *rcv_l,
384 struct sk_buff_head *xmitq)
385{
386 u16 ack = snd_l->snd_nxt - 1;
387
388 snd_l->ackers--;
389 rcv_l->bc_peer_is_up = true;
390 rcv_l->state = LINK_ESTABLISHED;
391 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
392 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
393 tipc_link_reset(rcv_l);
394 rcv_l->state = LINK_RESET;
395 if (!snd_l->ackers) {
396 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
397 tipc_link_reset(snd_l);
398 snd_l->state = LINK_RESET;
399 __skb_queue_purge(xmitq);
400 }
401}
402
403int tipc_link_bc_peers(struct tipc_link *l)
404{
405 return l->ackers;
406}
407
408static u16 link_bc_rcv_gap(struct tipc_link *l)
409{
410 struct sk_buff *skb = skb_peek(&l->deferdq);
411 u16 gap = 0;
412
413 if (more(l->snd_nxt, l->rcv_nxt))
414 gap = l->snd_nxt - l->rcv_nxt;
415 if (skb)
416 gap = buf_seqno(skb) - l->rcv_nxt;
417 return gap;
418}
419
420void tipc_link_set_mtu(struct tipc_link *l, int mtu)
421{
422 l->mtu = mtu;
423}
424
425int tipc_link_mtu(struct tipc_link *l)
426{
427 return l->mtu;
428}
429
430int tipc_link_mss(struct tipc_link *l)
431{
432#ifdef CONFIG_TIPC_CRYPTO
433 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
434#else
435 return l->mtu - INT_H_SIZE;
436#endif
437}
438
439u16 tipc_link_rcv_nxt(struct tipc_link *l)
440{
441 return l->rcv_nxt;
442}
443
444u16 tipc_link_acked(struct tipc_link *l)
445{
446 return l->acked;
447}
448
449char *tipc_link_name(struct tipc_link *l)
450{
451 return l->name;
452}
453
454u32 tipc_link_state(struct tipc_link *l)
455{
456 return l->state;
457}
458
459/**
460 * tipc_link_create - create a new link
461 * @net: pointer to associated network namespace
462 * @if_name: associated interface name
463 * @bearer_id: id (index) of associated bearer
464 * @tolerance: link tolerance to be used by link
465 * @net_plane: network plane (A,B,c..) this link belongs to
466 * @mtu: mtu to be advertised by link
467 * @priority: priority to be used by link
468 * @min_win: minimal send window to be used by link
469 * @max_win: maximal send window to be used by link
470 * @session: session to be used by link
471 * @peer: node id of peer node
472 * @peer_caps: bitmap describing peer node capabilities
473 * @bc_sndlink: the namespace global link used for broadcast sending
474 * @bc_rcvlink: the peer specific link used for broadcast reception
475 * @inputq: queue to put messages ready for delivery
476 * @namedq: queue to put binding table update messages ready for delivery
477 * @link: return value, pointer to put the created link
478 * @self: local unicast link id
479 * @peer_id: 128-bit ID of peer
480 *
481 * Return: true if link was created, otherwise false
482 */
483bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
484 int tolerance, char net_plane, u32 mtu, int priority,
485 u32 min_win, u32 max_win, u32 session, u32 self,
486 u32 peer, u8 *peer_id, u16 peer_caps,
487 struct tipc_link *bc_sndlink,
488 struct tipc_link *bc_rcvlink,
489 struct sk_buff_head *inputq,
490 struct sk_buff_head *namedq,
491 struct tipc_link **link)
492{
493 char peer_str[NODE_ID_STR_LEN] = {0,};
494 char self_str[NODE_ID_STR_LEN] = {0,};
495 struct tipc_link *l;
496
497 l = kzalloc(sizeof(*l), GFP_ATOMIC);
498 if (!l)
499 return false;
500 *link = l;
501 l->session = session;
502
503 /* Set link name for unicast links only */
504 if (peer_id) {
505 tipc_nodeid2string(self_str, tipc_own_id(net));
506 if (strlen(self_str) > 16)
507 sprintf(self_str, "%x", self);
508 tipc_nodeid2string(peer_str, peer_id);
509 if (strlen(peer_str) > 16)
510 sprintf(peer_str, "%x", peer);
511 }
512 /* Peer i/f name will be completed by reset/activate message */
513 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
514 self_str, if_name, peer_str);
515
516 strcpy(l->if_name, if_name);
517 l->addr = peer;
518 l->peer_caps = peer_caps;
519 l->net = net;
520 l->in_session = false;
521 l->bearer_id = bearer_id;
522 l->tolerance = tolerance;
523 if (bc_rcvlink)
524 bc_rcvlink->tolerance = tolerance;
525 l->net_plane = net_plane;
526 l->advertised_mtu = mtu;
527 l->mtu = mtu;
528 l->priority = priority;
529 tipc_link_set_queue_limits(l, min_win, max_win);
530 l->ackers = 1;
531 l->bc_sndlink = bc_sndlink;
532 l->bc_rcvlink = bc_rcvlink;
533 l->inputq = inputq;
534 l->namedq = namedq;
535 l->state = LINK_RESETTING;
536 __skb_queue_head_init(&l->transmq);
537 __skb_queue_head_init(&l->backlogq);
538 __skb_queue_head_init(&l->deferdq);
539 __skb_queue_head_init(&l->failover_deferdq);
540 skb_queue_head_init(&l->wakeupq);
541 skb_queue_head_init(l->inputq);
542 return true;
543}
544
545/**
546 * tipc_link_bc_create - create new link to be used for broadcast
547 * @net: pointer to associated network namespace
548 * @mtu: mtu to be used initially if no peers
549 * @min_win: minimal send window to be used by link
550 * @max_win: maximal send window to be used by link
551 * @inputq: queue to put messages ready for delivery
552 * @namedq: queue to put binding table update messages ready for delivery
553 * @link: return value, pointer to put the created link
554 * @ownnode: identity of own node
555 * @peer: node id of peer node
556 * @peer_id: 128-bit ID of peer
557 * @peer_caps: bitmap describing peer node capabilities
558 * @bc_sndlink: the namespace global link used for broadcast sending
559 *
560 * Return: true if link was created, otherwise false
561 */
562bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
563 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
564 struct sk_buff_head *inputq,
565 struct sk_buff_head *namedq,
566 struct tipc_link *bc_sndlink,
567 struct tipc_link **link)
568{
569 struct tipc_link *l;
570
571 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
572 max_win, 0, ownnode, peer, NULL, peer_caps,
573 bc_sndlink, NULL, inputq, namedq, link))
574 return false;
575
576 l = *link;
577 if (peer_id) {
578 char peer_str[NODE_ID_STR_LEN] = {0,};
579
580 tipc_nodeid2string(peer_str, peer_id);
581 if (strlen(peer_str) > 16)
582 sprintf(peer_str, "%x", peer);
583 /* Broadcast receiver link name: "broadcast-link:<peer>" */
584 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
585 peer_str);
586 } else {
587 strcpy(l->name, tipc_bclink_name);
588 }
589 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
590 tipc_link_reset(l);
591 l->state = LINK_RESET;
592 l->ackers = 0;
593 l->bc_rcvlink = l;
594
595 /* Broadcast send link is always up */
596 if (link_is_bc_sndlink(l))
597 l->state = LINK_ESTABLISHED;
598
599 /* Disable replicast if even a single peer doesn't support it */
600 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
601 tipc_bcast_toggle_rcast(net, false);
602
603 return true;
604}
605
606/**
607 * tipc_link_fsm_evt - link finite state machine
608 * @l: pointer to link
609 * @evt: state machine event to be processed
610 */
611int tipc_link_fsm_evt(struct tipc_link *l, int evt)
612{
613 int rc = 0;
614 int old_state = l->state;
615
616 switch (l->state) {
617 case LINK_RESETTING:
618 switch (evt) {
619 case LINK_PEER_RESET_EVT:
620 l->state = LINK_PEER_RESET;
621 break;
622 case LINK_RESET_EVT:
623 l->state = LINK_RESET;
624 break;
625 case LINK_FAILURE_EVT:
626 case LINK_FAILOVER_BEGIN_EVT:
627 case LINK_ESTABLISH_EVT:
628 case LINK_FAILOVER_END_EVT:
629 case LINK_SYNCH_BEGIN_EVT:
630 case LINK_SYNCH_END_EVT:
631 default:
632 goto illegal_evt;
633 }
634 break;
635 case LINK_RESET:
636 switch (evt) {
637 case LINK_PEER_RESET_EVT:
638 l->state = LINK_ESTABLISHING;
639 break;
640 case LINK_FAILOVER_BEGIN_EVT:
641 l->state = LINK_FAILINGOVER;
642 break;
643 case LINK_FAILURE_EVT:
644 case LINK_RESET_EVT:
645 case LINK_ESTABLISH_EVT:
646 case LINK_FAILOVER_END_EVT:
647 break;
648 case LINK_SYNCH_BEGIN_EVT:
649 case LINK_SYNCH_END_EVT:
650 default:
651 goto illegal_evt;
652 }
653 break;
654 case LINK_PEER_RESET:
655 switch (evt) {
656 case LINK_RESET_EVT:
657 l->state = LINK_ESTABLISHING;
658 break;
659 case LINK_PEER_RESET_EVT:
660 case LINK_ESTABLISH_EVT:
661 case LINK_FAILURE_EVT:
662 break;
663 case LINK_SYNCH_BEGIN_EVT:
664 case LINK_SYNCH_END_EVT:
665 case LINK_FAILOVER_BEGIN_EVT:
666 case LINK_FAILOVER_END_EVT:
667 default:
668 goto illegal_evt;
669 }
670 break;
671 case LINK_FAILINGOVER:
672 switch (evt) {
673 case LINK_FAILOVER_END_EVT:
674 l->state = LINK_RESET;
675 break;
676 case LINK_PEER_RESET_EVT:
677 case LINK_RESET_EVT:
678 case LINK_ESTABLISH_EVT:
679 case LINK_FAILURE_EVT:
680 break;
681 case LINK_FAILOVER_BEGIN_EVT:
682 case LINK_SYNCH_BEGIN_EVT:
683 case LINK_SYNCH_END_EVT:
684 default:
685 goto illegal_evt;
686 }
687 break;
688 case LINK_ESTABLISHING:
689 switch (evt) {
690 case LINK_ESTABLISH_EVT:
691 l->state = LINK_ESTABLISHED;
692 break;
693 case LINK_FAILOVER_BEGIN_EVT:
694 l->state = LINK_FAILINGOVER;
695 break;
696 case LINK_RESET_EVT:
697 l->state = LINK_RESET;
698 break;
699 case LINK_FAILURE_EVT:
700 case LINK_PEER_RESET_EVT:
701 case LINK_SYNCH_BEGIN_EVT:
702 case LINK_FAILOVER_END_EVT:
703 break;
704 case LINK_SYNCH_END_EVT:
705 default:
706 goto illegal_evt;
707 }
708 break;
709 case LINK_ESTABLISHED:
710 switch (evt) {
711 case LINK_PEER_RESET_EVT:
712 l->state = LINK_PEER_RESET;
713 rc |= TIPC_LINK_DOWN_EVT;
714 break;
715 case LINK_FAILURE_EVT:
716 l->state = LINK_RESETTING;
717 rc |= TIPC_LINK_DOWN_EVT;
718 break;
719 case LINK_RESET_EVT:
720 l->state = LINK_RESET;
721 break;
722 case LINK_ESTABLISH_EVT:
723 case LINK_SYNCH_END_EVT:
724 break;
725 case LINK_SYNCH_BEGIN_EVT:
726 l->state = LINK_SYNCHING;
727 break;
728 case LINK_FAILOVER_BEGIN_EVT:
729 case LINK_FAILOVER_END_EVT:
730 default:
731 goto illegal_evt;
732 }
733 break;
734 case LINK_SYNCHING:
735 switch (evt) {
736 case LINK_PEER_RESET_EVT:
737 l->state = LINK_PEER_RESET;
738 rc |= TIPC_LINK_DOWN_EVT;
739 break;
740 case LINK_FAILURE_EVT:
741 l->state = LINK_RESETTING;
742 rc |= TIPC_LINK_DOWN_EVT;
743 break;
744 case LINK_RESET_EVT:
745 l->state = LINK_RESET;
746 break;
747 case LINK_ESTABLISH_EVT:
748 case LINK_SYNCH_BEGIN_EVT:
749 break;
750 case LINK_SYNCH_END_EVT:
751 l->state = LINK_ESTABLISHED;
752 break;
753 case LINK_FAILOVER_BEGIN_EVT:
754 case LINK_FAILOVER_END_EVT:
755 default:
756 goto illegal_evt;
757 }
758 break;
759 default:
760 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
761 }
762 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
763 return rc;
764illegal_evt:
765 pr_err("Illegal FSM event %x in state %x on link %s\n",
766 evt, l->state, l->name);
767 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
768 return rc;
769}
770
771/* link_profile_stats - update statistical profiling of traffic
772 */
773static void link_profile_stats(struct tipc_link *l)
774{
775 struct sk_buff *skb;
776 struct tipc_msg *msg;
777 int length;
778
779 /* Update counters used in statistical profiling of send traffic */
780 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
781 l->stats.queue_sz_counts++;
782
783 skb = skb_peek(&l->transmq);
784 if (!skb)
785 return;
786 msg = buf_msg(skb);
787 length = msg_size(msg);
788
789 if (msg_user(msg) == MSG_FRAGMENTER) {
790 if (msg_type(msg) != FIRST_FRAGMENT)
791 return;
792 length = msg_size(msg_inner_hdr(msg));
793 }
794 l->stats.msg_lengths_total += length;
795 l->stats.msg_length_counts++;
796 if (length <= 64)
797 l->stats.msg_length_profile[0]++;
798 else if (length <= 256)
799 l->stats.msg_length_profile[1]++;
800 else if (length <= 1024)
801 l->stats.msg_length_profile[2]++;
802 else if (length <= 4096)
803 l->stats.msg_length_profile[3]++;
804 else if (length <= 16384)
805 l->stats.msg_length_profile[4]++;
806 else if (length <= 32768)
807 l->stats.msg_length_profile[5]++;
808 else
809 l->stats.msg_length_profile[6]++;
810}
811
812/**
813 * tipc_link_too_silent - check if link is "too silent"
814 * @l: tipc link to be checked
815 *
816 * Return: true if the link 'silent_intv_cnt' is about to reach the
817 * 'abort_limit' value, otherwise false
818 */
819bool tipc_link_too_silent(struct tipc_link *l)
820{
821 return (l->silent_intv_cnt + 2 > l->abort_limit);
822}
823
824/* tipc_link_timeout - perform periodic task as instructed from node timeout
825 */
826int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
827{
828 int mtyp = 0;
829 int rc = 0;
830 bool state = false;
831 bool probe = false;
832 bool setup = false;
833 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
834 u16 bc_acked = l->bc_rcvlink->acked;
835 struct tipc_mon_state *mstate = &l->mon_state;
836
837 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
838 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
839 switch (l->state) {
840 case LINK_ESTABLISHED:
841 case LINK_SYNCHING:
842 mtyp = STATE_MSG;
843 link_profile_stats(l);
844 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
845 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
846 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
847 state = bc_acked != bc_snt;
848 state |= l->bc_rcvlink->rcv_unacked;
849 state |= l->rcv_unacked;
850 state |= !skb_queue_empty(&l->transmq);
851 probe = mstate->probing;
852 probe |= l->silent_intv_cnt;
853 if (probe || mstate->monitoring)
854 l->silent_intv_cnt++;
855 probe |= !skb_queue_empty(&l->deferdq);
856 if (l->snd_nxt == l->checkpoint) {
857 tipc_link_update_cwin(l, 0, 0);
858 probe = true;
859 }
860 l->checkpoint = l->snd_nxt;
861 break;
862 case LINK_RESET:
863 setup = l->rst_cnt++ <= 4;
864 setup |= !(l->rst_cnt % 16);
865 mtyp = RESET_MSG;
866 break;
867 case LINK_ESTABLISHING:
868 setup = true;
869 mtyp = ACTIVATE_MSG;
870 break;
871 case LINK_PEER_RESET:
872 case LINK_RESETTING:
873 case LINK_FAILINGOVER:
874 break;
875 default:
876 break;
877 }
878
879 if (state || probe || setup)
880 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
881
882 return rc;
883}
884
885/**
886 * link_schedule_user - schedule a message sender for wakeup after congestion
887 * @l: congested link
888 * @hdr: header of message that is being sent
889 * Create pseudo msg to send back to user when congestion abates
890 */
891static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
892{
893 u32 dnode = tipc_own_addr(l->net);
894 u32 dport = msg_origport(hdr);
895 struct sk_buff *skb;
896
897 /* Create and schedule wakeup pseudo message */
898 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
899 dnode, l->addr, dport, 0, 0);
900 if (!skb)
901 return -ENOBUFS;
902 msg_set_dest_droppable(buf_msg(skb), true);
903 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
904 skb_queue_tail(&l->wakeupq, skb);
905 l->stats.link_congs++;
906 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
907 return -ELINKCONG;
908}
909
910/**
911 * link_prepare_wakeup - prepare users for wakeup after congestion
912 * @l: congested link
913 * Wake up a number of waiting users, as permitted by available space
914 * in the send queue
915 */
916static void link_prepare_wakeup(struct tipc_link *l)
917{
918 struct sk_buff_head *wakeupq = &l->wakeupq;
919 struct sk_buff_head *inputq = l->inputq;
920 struct sk_buff *skb, *tmp;
921 struct sk_buff_head tmpq;
922 int avail[5] = {0,};
923 int imp = 0;
924
925 __skb_queue_head_init(&tmpq);
926
927 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
928 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
929
930 skb_queue_walk_safe(wakeupq, skb, tmp) {
931 imp = TIPC_SKB_CB(skb)->chain_imp;
932 if (avail[imp] <= 0)
933 continue;
934 avail[imp]--;
935 __skb_unlink(skb, wakeupq);
936 __skb_queue_tail(&tmpq, skb);
937 }
938
939 spin_lock_bh(&inputq->lock);
940 skb_queue_splice_tail(&tmpq, inputq);
941 spin_unlock_bh(&inputq->lock);
942
943}
944
945/**
946 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
947 * the given skb should be next attempted
948 * @skb: skb to set a future retransmission time for
949 * @l: link the skb will be transmitted on
950 */
951static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
952 struct tipc_link *l)
953{
954 if (link_is_bc_sndlink(l))
955 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
956 else
957 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
958}
959
960void tipc_link_reset(struct tipc_link *l)
961{
962 struct sk_buff_head list;
963 u32 imp;
964
965 __skb_queue_head_init(&list);
966
967 l->in_session = false;
968 /* Force re-synch of peer session number before establishing */
969 l->peer_session--;
970 l->session++;
971 l->mtu = l->advertised_mtu;
972
973 spin_lock_bh(&l->wakeupq.lock);
974 skb_queue_splice_init(&l->wakeupq, &list);
975 spin_unlock_bh(&l->wakeupq.lock);
976
977 spin_lock_bh(&l->inputq->lock);
978 skb_queue_splice_init(&list, l->inputq);
979 spin_unlock_bh(&l->inputq->lock);
980
981 __skb_queue_purge(&l->transmq);
982 __skb_queue_purge(&l->deferdq);
983 __skb_queue_purge(&l->backlogq);
984 __skb_queue_purge(&l->failover_deferdq);
985 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
986 l->backlog[imp].len = 0;
987 l->backlog[imp].target_bskb = NULL;
988 }
989 kfree_skb(l->reasm_buf);
990 kfree_skb(l->reasm_tnlmsg);
991 kfree_skb(l->failover_reasm_skb);
992 l->reasm_buf = NULL;
993 l->reasm_tnlmsg = NULL;
994 l->failover_reasm_skb = NULL;
995 l->rcv_unacked = 0;
996 l->snd_nxt = 1;
997 l->rcv_nxt = 1;
998 l->snd_nxt_state = 1;
999 l->rcv_nxt_state = 1;
1000 l->acked = 0;
1001 l->last_gap = 0;
1002 kfree(l->last_ga);
1003 l->last_ga = NULL;
1004 l->silent_intv_cnt = 0;
1005 l->rst_cnt = 0;
1006 l->bc_peer_is_up = false;
1007 memset(&l->mon_state, 0, sizeof(l->mon_state));
1008 tipc_link_reset_stats(l);
1009}
1010
1011/**
1012 * tipc_link_xmit(): enqueue buffer list according to queue situation
1013 * @l: link to use
1014 * @list: chain of buffers containing message
1015 * @xmitq: returned list of packets to be sent by caller
1016 *
1017 * Consumes the buffer chain.
1018 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1019 * Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
1020 */
1021int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1022 struct sk_buff_head *xmitq)
1023{
1024 struct sk_buff_head *backlogq = &l->backlogq;
1025 struct sk_buff_head *transmq = &l->transmq;
1026 struct sk_buff *skb, *_skb;
1027 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1028 u16 ack = l->rcv_nxt - 1;
1029 u16 seqno = l->snd_nxt;
1030 int pkt_cnt = skb_queue_len(list);
1031 unsigned int mss = tipc_link_mss(l);
1032 unsigned int cwin = l->window;
1033 unsigned int mtu = l->mtu;
1034 struct tipc_msg *hdr;
1035 bool new_bundle;
1036 int rc = 0;
1037 int imp;
1038
1039 if (pkt_cnt <= 0)
1040 return 0;
1041
1042 hdr = buf_msg(skb_peek(list));
1043 if (unlikely(msg_size(hdr) > mtu)) {
1044 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1045 skb_queue_len(list), msg_user(hdr),
1046 msg_type(hdr), msg_size(hdr), mtu);
1047 __skb_queue_purge(list);
1048 return -EMSGSIZE;
1049 }
1050
1051 imp = msg_importance(hdr);
1052 /* Allow oversubscription of one data msg per source at congestion */
1053 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1054 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1055 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1056 return -ENOBUFS;
1057 }
1058 rc = link_schedule_user(l, hdr);
1059 }
1060
1061 if (pkt_cnt > 1) {
1062 l->stats.sent_fragmented++;
1063 l->stats.sent_fragments += pkt_cnt;
1064 }
1065
1066 /* Prepare each packet for sending, and add to relevant queue: */
1067 while ((skb = __skb_dequeue(list))) {
1068 if (likely(skb_queue_len(transmq) < cwin)) {
1069 hdr = buf_msg(skb);
1070 msg_set_seqno(hdr, seqno);
1071 msg_set_ack(hdr, ack);
1072 msg_set_bcast_ack(hdr, bc_ack);
1073 _skb = skb_clone(skb, GFP_ATOMIC);
1074 if (!_skb) {
1075 kfree_skb(skb);
1076 __skb_queue_purge(list);
1077 return -ENOBUFS;
1078 }
1079 __skb_queue_tail(transmq, skb);
1080 tipc_link_set_skb_retransmit_time(skb, l);
1081 __skb_queue_tail(xmitq, _skb);
1082 TIPC_SKB_CB(skb)->ackers = l->ackers;
1083 l->rcv_unacked = 0;
1084 l->stats.sent_pkts++;
1085 seqno++;
1086 continue;
1087 }
1088 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1089 mss, l->addr, &new_bundle)) {
1090 if (skb) {
1091 /* Keep a ref. to the skb for next try */
1092 l->backlog[imp].target_bskb = skb;
1093 l->backlog[imp].len++;
1094 __skb_queue_tail(backlogq, skb);
1095 } else {
1096 if (new_bundle) {
1097 l->stats.sent_bundles++;
1098 l->stats.sent_bundled++;
1099 }
1100 l->stats.sent_bundled++;
1101 }
1102 continue;
1103 }
1104 l->backlog[imp].target_bskb = NULL;
1105 l->backlog[imp].len += (1 + skb_queue_len(list));
1106 __skb_queue_tail(backlogq, skb);
1107 skb_queue_splice_tail_init(list, backlogq);
1108 }
1109 l->snd_nxt = seqno;
1110 return rc;
1111}
1112
1113static void tipc_link_update_cwin(struct tipc_link *l, int released,
1114 bool retransmitted)
1115{
1116 int bklog_len = skb_queue_len(&l->backlogq);
1117 struct sk_buff_head *txq = &l->transmq;
1118 int txq_len = skb_queue_len(txq);
1119 u16 cwin = l->window;
1120
1121 /* Enter fast recovery */
1122 if (unlikely(retransmitted)) {
1123 l->ssthresh = max_t(u16, l->window / 2, 300);
1124 l->window = min_t(u16, l->ssthresh, l->window);
1125 return;
1126 }
1127 /* Enter slow start */
1128 if (unlikely(!released)) {
1129 l->ssthresh = max_t(u16, l->window / 2, 300);
1130 l->window = l->min_win;
1131 return;
1132 }
1133 /* Don't increase window if no pressure on the transmit queue */
1134 if (txq_len + bklog_len < cwin)
1135 return;
1136
1137 /* Don't increase window if there are holes the transmit queue */
1138 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1139 return;
1140
1141 l->cong_acks += released;
1142
1143 /* Slow start */
1144 if (cwin <= l->ssthresh) {
1145 l->window = min_t(u16, cwin + released, l->max_win);
1146 return;
1147 }
1148 /* Congestion avoidance */
1149 if (l->cong_acks < cwin)
1150 return;
1151 l->window = min_t(u16, ++cwin, l->max_win);
1152 l->cong_acks = 0;
1153}
1154
1155static void tipc_link_advance_backlog(struct tipc_link *l,
1156 struct sk_buff_head *xmitq)
1157{
1158 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1159 struct sk_buff_head *txq = &l->transmq;
1160 struct sk_buff *skb, *_skb;
1161 u16 ack = l->rcv_nxt - 1;
1162 u16 seqno = l->snd_nxt;
1163 struct tipc_msg *hdr;
1164 u16 cwin = l->window;
1165 u32 imp;
1166
1167 while (skb_queue_len(txq) < cwin) {
1168 skb = skb_peek(&l->backlogq);
1169 if (!skb)
1170 break;
1171 _skb = skb_clone(skb, GFP_ATOMIC);
1172 if (!_skb)
1173 break;
1174 __skb_dequeue(&l->backlogq);
1175 hdr = buf_msg(skb);
1176 imp = msg_importance(hdr);
1177 l->backlog[imp].len--;
1178 if (unlikely(skb == l->backlog[imp].target_bskb))
1179 l->backlog[imp].target_bskb = NULL;
1180 __skb_queue_tail(&l->transmq, skb);
1181 tipc_link_set_skb_retransmit_time(skb, l);
1182
1183 __skb_queue_tail(xmitq, _skb);
1184 TIPC_SKB_CB(skb)->ackers = l->ackers;
1185 msg_set_seqno(hdr, seqno);
1186 msg_set_ack(hdr, ack);
1187 msg_set_bcast_ack(hdr, bc_ack);
1188 l->rcv_unacked = 0;
1189 l->stats.sent_pkts++;
1190 seqno++;
1191 }
1192 l->snd_nxt = seqno;
1193}
1194
1195/**
1196 * link_retransmit_failure() - Detect repeated retransmit failures
1197 * @l: tipc link sender
1198 * @r: tipc link receiver (= l in case of unicast)
1199 * @rc: returned code
1200 *
1201 * Return: true if the repeated retransmit failures happens, otherwise
1202 * false
1203 */
1204static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1205 int *rc)
1206{
1207 struct sk_buff *skb = skb_peek(&l->transmq);
1208 struct tipc_msg *hdr;
1209
1210 if (!skb)
1211 return false;
1212
1213 if (!TIPC_SKB_CB(skb)->retr_cnt)
1214 return false;
1215
1216 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1217 msecs_to_jiffies(r->tolerance * 10)))
1218 return false;
1219
1220 hdr = buf_msg(skb);
1221 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1222 return false;
1223
1224 pr_warn("Retransmission failure on link <%s>\n", l->name);
1225 link_print(l, "State of link ");
1226 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1227 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1228 pr_info("sqno %u, prev: %x, dest: %x\n",
1229 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1230 pr_info("retr_stamp %d, retr_cnt %d\n",
1231 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1232 TIPC_SKB_CB(skb)->retr_cnt);
1233
1234 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1235 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1236 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1237
1238 if (link_is_bc_sndlink(l)) {
1239 r->state = LINK_RESET;
1240 *rc |= TIPC_LINK_DOWN_EVT;
1241 } else {
1242 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1243 }
1244
1245 return true;
1246}
1247
1248/* tipc_data_input - deliver data and name distr msgs to upper layer
1249 *
1250 * Consumes buffer if message is of right type
1251 * Node lock must be held
1252 */
1253static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1254 struct sk_buff_head *inputq)
1255{
1256 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1257 struct tipc_msg *hdr = buf_msg(skb);
1258
1259 switch (msg_user(hdr)) {
1260 case TIPC_LOW_IMPORTANCE:
1261 case TIPC_MEDIUM_IMPORTANCE:
1262 case TIPC_HIGH_IMPORTANCE:
1263 case TIPC_CRITICAL_IMPORTANCE:
1264 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1265 skb_queue_tail(mc_inputq, skb);
1266 return true;
1267 }
1268 fallthrough;
1269 case CONN_MANAGER:
1270 skb_queue_tail(inputq, skb);
1271 return true;
1272 case GROUP_PROTOCOL:
1273 skb_queue_tail(mc_inputq, skb);
1274 return true;
1275 case NAME_DISTRIBUTOR:
1276 l->bc_rcvlink->state = LINK_ESTABLISHED;
1277 skb_queue_tail(l->namedq, skb);
1278 return true;
1279 case MSG_BUNDLER:
1280 case TUNNEL_PROTOCOL:
1281 case MSG_FRAGMENTER:
1282 case BCAST_PROTOCOL:
1283 return false;
1284#ifdef CONFIG_TIPC_CRYPTO
1285 case MSG_CRYPTO:
1286 if (sysctl_tipc_key_exchange_enabled &&
1287 TIPC_SKB_CB(skb)->decrypted) {
1288 tipc_crypto_msg_rcv(l->net, skb);
1289 return true;
1290 }
1291 fallthrough;
1292#endif
1293 default:
1294 pr_warn("Dropping received illegal msg type\n");
1295 kfree_skb(skb);
1296 return true;
1297 }
1298}
1299
1300/* tipc_link_input - process packet that has passed link protocol check
1301 *
1302 * Consumes buffer
1303 */
1304static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1305 struct sk_buff_head *inputq,
1306 struct sk_buff **reasm_skb)
1307{
1308 struct tipc_msg *hdr = buf_msg(skb);
1309 struct sk_buff *iskb;
1310 struct sk_buff_head tmpq;
1311 int usr = msg_user(hdr);
1312 int pos = 0;
1313
1314 if (usr == MSG_BUNDLER) {
1315 skb_queue_head_init(&tmpq);
1316 l->stats.recv_bundles++;
1317 l->stats.recv_bundled += msg_msgcnt(hdr);
1318 while (tipc_msg_extract(skb, &iskb, &pos))
1319 tipc_data_input(l, iskb, &tmpq);
1320 tipc_skb_queue_splice_tail(&tmpq, inputq);
1321 return 0;
1322 } else if (usr == MSG_FRAGMENTER) {
1323 l->stats.recv_fragments++;
1324 if (tipc_buf_append(reasm_skb, &skb)) {
1325 l->stats.recv_fragmented++;
1326 tipc_data_input(l, skb, inputq);
1327 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1328 pr_warn_ratelimited("Unable to build fragment list\n");
1329 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1330 }
1331 return 0;
1332 } else if (usr == BCAST_PROTOCOL) {
1333 tipc_bcast_lock(l->net);
1334 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1335 tipc_bcast_unlock(l->net);
1336 }
1337
1338 kfree_skb(skb);
1339 return 0;
1340}
1341
1342/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1343 * inner message along with the ones in the old link's
1344 * deferdq
1345 * @l: tunnel link
1346 * @skb: TUNNEL_PROTOCOL message
1347 * @inputq: queue to put messages ready for delivery
1348 */
1349static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1350 struct sk_buff_head *inputq)
1351{
1352 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1353 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1354 struct sk_buff_head *fdefq = &l->failover_deferdq;
1355 struct tipc_msg *hdr = buf_msg(skb);
1356 struct sk_buff *iskb;
1357 int ipos = 0;
1358 int rc = 0;
1359 u16 seqno;
1360
1361 if (msg_type(hdr) == SYNCH_MSG) {
1362 kfree_skb(skb);
1363 return 0;
1364 }
1365
1366 /* Not a fragment? */
1367 if (likely(!msg_nof_fragms(hdr))) {
1368 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1369 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1370 skb_queue_len(fdefq));
1371 return 0;
1372 }
1373 kfree_skb(skb);
1374 } else {
1375 /* Set fragment type for buf_append */
1376 if (msg_fragm_no(hdr) == 1)
1377 msg_set_type(hdr, FIRST_FRAGMENT);
1378 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1379 msg_set_type(hdr, FRAGMENT);
1380 else
1381 msg_set_type(hdr, LAST_FRAGMENT);
1382
1383 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1384 /* Successful but non-complete reassembly? */
1385 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1386 return 0;
1387 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1388 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1389 }
1390 iskb = skb;
1391 }
1392
1393 do {
1394 seqno = buf_seqno(iskb);
1395 if (unlikely(less(seqno, l->drop_point))) {
1396 kfree_skb(iskb);
1397 continue;
1398 }
1399 if (unlikely(seqno != l->drop_point)) {
1400 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1401 continue;
1402 }
1403
1404 l->drop_point++;
1405 if (!tipc_data_input(l, iskb, inputq))
1406 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1407 if (unlikely(rc))
1408 break;
1409 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1410
1411 return rc;
1412}
1413
1414/**
1415 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1416 * @ga: returned pointer to the Gap ACK blocks if any
1417 * @l: the tipc link
1418 * @hdr: the PROTOCOL/STATE_MSG header
1419 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1420 *
1421 * Return: the total Gap ACK blocks size
1422 */
1423u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1424 struct tipc_msg *hdr, bool uc)
1425{
1426 struct tipc_gap_ack_blks *p;
1427 u16 sz = 0;
1428
1429 /* Does peer support the Gap ACK blocks feature? */
1430 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1431 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1432 sz = ntohs(p->len);
1433 /* Sanity check */
1434 if (sz == struct_size(p, gacks, size_add(p->ugack_cnt, p->bgack_cnt))) {
1435 /* Good, check if the desired type exists */
1436 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1437 goto ok;
1438 /* Backward compatible: peer might not support bc, but uc? */
1439 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1440 if (p->ugack_cnt) {
1441 p->bgack_cnt = 0;
1442 goto ok;
1443 }
1444 }
1445 }
1446 /* Other cases: ignore! */
1447 p = NULL;
1448
1449ok:
1450 *ga = p;
1451 return sz;
1452}
1453
1454static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1455 struct tipc_link *l, u8 start_index)
1456{
1457 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1458 struct sk_buff *skb = skb_peek(&l->deferdq);
1459 u16 expect, seqno = 0;
1460 u8 n = 0;
1461
1462 if (!skb)
1463 return 0;
1464
1465 expect = buf_seqno(skb);
1466 skb_queue_walk(&l->deferdq, skb) {
1467 seqno = buf_seqno(skb);
1468 if (unlikely(more(seqno, expect))) {
1469 gacks[n].ack = htons(expect - 1);
1470 gacks[n].gap = htons(seqno - expect);
1471 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1472 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1473 l->name, n,
1474 skb_queue_len(&l->deferdq));
1475 return n;
1476 }
1477 } else if (unlikely(less(seqno, expect))) {
1478 pr_warn("Unexpected skb in deferdq!\n");
1479 continue;
1480 }
1481 expect = seqno + 1;
1482 }
1483
1484 /* last block */
1485 gacks[n].ack = htons(seqno);
1486 gacks[n].gap = 0;
1487 n++;
1488 return n;
1489}
1490
1491/* tipc_build_gap_ack_blks - build Gap ACK blocks
1492 * @l: tipc unicast link
1493 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1494 *
1495 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1496 * links of a certain peer, the buffer after built has the network data format
1497 * as found at the struct tipc_gap_ack_blks definition.
1498 *
1499 * returns the actual allocated memory size
1500 */
1501static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1502{
1503 struct tipc_link *bcl = l->bc_rcvlink;
1504 struct tipc_gap_ack_blks *ga;
1505 u16 len;
1506
1507 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1508
1509 /* Start with broadcast link first */
1510 tipc_bcast_lock(bcl->net);
1511 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1512 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1513 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1514 tipc_bcast_unlock(bcl->net);
1515
1516 /* Now for unicast link, but an explicit NACK only (???) */
1517 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1518 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1519
1520 /* Total len */
1521 len = struct_size(ga, gacks, size_add(ga->bgack_cnt, ga->ugack_cnt));
1522 ga->len = htons(len);
1523 return len;
1524}
1525
1526/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1527 * acked packets, also doing retransmissions if
1528 * gaps found
1529 * @l: tipc link with transmq queue to be advanced
1530 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1531 * @acked: seqno of last packet acked by peer without any gaps before
1532 * @gap: # of gap packets
1533 * @ga: buffer pointer to Gap ACK blocks from peer
1534 * @xmitq: queue for accumulating the retransmitted packets if any
1535 * @retransmitted: returned boolean value if a retransmission is really issued
1536 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1537 * happens (- unlikely case)
1538 *
1539 * Return: the number of packets released from the link transmq
1540 */
1541static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1542 u16 acked, u16 gap,
1543 struct tipc_gap_ack_blks *ga,
1544 struct sk_buff_head *xmitq,
1545 bool *retransmitted, int *rc)
1546{
1547 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1548 struct tipc_gap_ack *gacks = NULL;
1549 struct sk_buff *skb, *_skb, *tmp;
1550 struct tipc_msg *hdr;
1551 u32 qlen = skb_queue_len(&l->transmq);
1552 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1553 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1554 u16 ack = l->rcv_nxt - 1;
1555 u16 seqno, n = 0;
1556 u16 end = r->acked, start = end, offset = r->last_gap;
1557 u16 si = (last_ga) ? last_ga->start_index : 0;
1558 bool is_uc = !link_is_bc_sndlink(l);
1559 bool bc_has_acked = false;
1560
1561 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1562
1563 /* Determine Gap ACK blocks if any for the particular link */
1564 if (ga && is_uc) {
1565 /* Get the Gap ACKs, uc part */
1566 gack_cnt = ga->ugack_cnt;
1567 gacks = &ga->gacks[ga->bgack_cnt];
1568 } else if (ga) {
1569 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1570 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1571 GFP_ATOMIC);
1572 if (likely(this_ga)) {
1573 this_ga->start_index = 0;
1574 /* Start with the bc Gap ACKs */
1575 gack_cnt = this_ga->bgack_cnt;
1576 gacks = &this_ga->gacks[0];
1577 } else {
1578 /* Hmm, we can get in trouble..., simply ignore it */
1579 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1580 }
1581 }
1582
1583 /* Advance the link transmq */
1584 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1585 seqno = buf_seqno(skb);
1586
1587next_gap_ack:
1588 if (less_eq(seqno, nacked)) {
1589 if (is_uc)
1590 goto release;
1591 /* Skip packets peer has already acked */
1592 if (!more(seqno, r->acked))
1593 continue;
1594 /* Get the next of last Gap ACK blocks */
1595 while (more(seqno, end)) {
1596 if (!last_ga || si >= last_ga->bgack_cnt)
1597 break;
1598 start = end + offset + 1;
1599 end = ntohs(last_ga->gacks[si].ack);
1600 offset = ntohs(last_ga->gacks[si].gap);
1601 si++;
1602 WARN_ONCE(more(start, end) ||
1603 (!offset &&
1604 si < last_ga->bgack_cnt) ||
1605 si > MAX_GAP_ACK_BLKS,
1606 "Corrupted Gap ACK: %d %d %d %d %d\n",
1607 start, end, offset, si,
1608 last_ga->bgack_cnt);
1609 }
1610 /* Check against the last Gap ACK block */
1611 if (tipc_in_range(seqno, start, end))
1612 continue;
1613 /* Update/release the packet peer is acking */
1614 bc_has_acked = true;
1615 if (--TIPC_SKB_CB(skb)->ackers)
1616 continue;
1617release:
1618 /* release skb */
1619 __skb_unlink(skb, &l->transmq);
1620 kfree_skb(skb);
1621 } else if (less_eq(seqno, nacked + ngap)) {
1622 /* First gap: check if repeated retrans failures? */
1623 if (unlikely(seqno == acked + 1 &&
1624 link_retransmit_failure(l, r, rc))) {
1625 /* Ignore this bc Gap ACKs if any */
1626 kfree(this_ga);
1627 this_ga = NULL;
1628 break;
1629 }
1630 /* retransmit skb if unrestricted*/
1631 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1632 continue;
1633 tipc_link_set_skb_retransmit_time(skb, l);
1634 _skb = pskb_copy(skb, GFP_ATOMIC);
1635 if (!_skb)
1636 continue;
1637 hdr = buf_msg(_skb);
1638 msg_set_ack(hdr, ack);
1639 msg_set_bcast_ack(hdr, bc_ack);
1640 _skb->priority = TC_PRIO_CONTROL;
1641 __skb_queue_tail(xmitq, _skb);
1642 l->stats.retransmitted++;
1643 if (!is_uc)
1644 r->stats.retransmitted++;
1645 *retransmitted = true;
1646 /* Increase actual retrans counter & mark first time */
1647 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1648 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1649 } else {
1650 /* retry with Gap ACK blocks if any */
1651 if (n >= gack_cnt)
1652 break;
1653 nacked = ntohs(gacks[n].ack);
1654 ngap = ntohs(gacks[n].gap);
1655 n++;
1656 goto next_gap_ack;
1657 }
1658 }
1659
1660 /* Renew last Gap ACK blocks for bc if needed */
1661 if (bc_has_acked) {
1662 if (this_ga) {
1663 kfree(last_ga);
1664 r->last_ga = this_ga;
1665 r->last_gap = gap;
1666 } else if (last_ga) {
1667 if (less(acked, start)) {
1668 si--;
1669 offset = start - acked - 1;
1670 } else if (less(acked, end)) {
1671 acked = end;
1672 }
1673 if (si < last_ga->bgack_cnt) {
1674 last_ga->start_index = si;
1675 r->last_gap = offset;
1676 } else {
1677 kfree(last_ga);
1678 r->last_ga = NULL;
1679 r->last_gap = 0;
1680 }
1681 } else {
1682 r->last_gap = 0;
1683 }
1684 r->acked = acked;
1685 } else {
1686 kfree(this_ga);
1687 }
1688
1689 return qlen - skb_queue_len(&l->transmq);
1690}
1691
1692/* tipc_link_build_state_msg: prepare link state message for transmission
1693 *
1694 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1695 * risk of ack storms towards the sender
1696 */
1697int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1698{
1699 if (!l)
1700 return 0;
1701
1702 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1703 if (link_is_bc_rcvlink(l)) {
1704 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1705 return 0;
1706 l->rcv_unacked = 0;
1707
1708 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1709 l->snd_nxt = l->rcv_nxt;
1710 return TIPC_LINK_SND_STATE;
1711 }
1712 /* Unicast ACK */
1713 l->rcv_unacked = 0;
1714 l->stats.sent_acks++;
1715 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1716 return 0;
1717}
1718
1719/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1720 */
1721void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1722{
1723 int mtyp = RESET_MSG;
1724 struct sk_buff *skb;
1725
1726 if (l->state == LINK_ESTABLISHING)
1727 mtyp = ACTIVATE_MSG;
1728
1729 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1730
1731 /* Inform peer that this endpoint is going down if applicable */
1732 skb = skb_peek_tail(xmitq);
1733 if (skb && (l->state == LINK_RESET))
1734 msg_set_peer_stopping(buf_msg(skb), 1);
1735}
1736
1737/* tipc_link_build_nack_msg: prepare link nack message for transmission
1738 * Note that sending of broadcast NACK is coordinated among nodes, to
1739 * reduce the risk of NACK storms towards the sender
1740 */
1741static int tipc_link_build_nack_msg(struct tipc_link *l,
1742 struct sk_buff_head *xmitq)
1743{
1744 u32 def_cnt = ++l->stats.deferred_recv;
1745 struct sk_buff_head *dfq = &l->deferdq;
1746 u32 defq_len = skb_queue_len(dfq);
1747 int match1, match2;
1748
1749 if (link_is_bc_rcvlink(l)) {
1750 match1 = def_cnt & 0xf;
1751 match2 = tipc_own_addr(l->net) & 0xf;
1752 if (match1 == match2)
1753 return TIPC_LINK_SND_STATE;
1754 return 0;
1755 }
1756
1757 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1758 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1759
1760 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1761 rcvgap, 0, 0, xmitq);
1762 }
1763 return 0;
1764}
1765
1766/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1767 * @l: the link that should handle the message
1768 * @skb: TIPC packet
1769 * @xmitq: queue to place packets to be sent after this call
1770 */
1771int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1772 struct sk_buff_head *xmitq)
1773{
1774 struct sk_buff_head *defq = &l->deferdq;
1775 struct tipc_msg *hdr = buf_msg(skb);
1776 u16 seqno, rcv_nxt, win_lim;
1777 int released = 0;
1778 int rc = 0;
1779
1780 /* Verify and update link state */
1781 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1782 return tipc_link_proto_rcv(l, skb, xmitq);
1783
1784 /* Don't send probe at next timeout expiration */
1785 l->silent_intv_cnt = 0;
1786
1787 do {
1788 hdr = buf_msg(skb);
1789 seqno = msg_seqno(hdr);
1790 rcv_nxt = l->rcv_nxt;
1791 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1792
1793 if (unlikely(!link_is_up(l))) {
1794 if (l->state == LINK_ESTABLISHING)
1795 rc = TIPC_LINK_UP_EVT;
1796 kfree_skb(skb);
1797 break;
1798 }
1799
1800 /* Drop if outside receive window */
1801 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1802 l->stats.duplicates++;
1803 kfree_skb(skb);
1804 break;
1805 }
1806 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1807 NULL, NULL, NULL, NULL);
1808
1809 /* Defer delivery if sequence gap */
1810 if (unlikely(seqno != rcv_nxt)) {
1811 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1812 l->stats.duplicates++;
1813 rc |= tipc_link_build_nack_msg(l, xmitq);
1814 break;
1815 }
1816
1817 /* Deliver packet */
1818 l->rcv_nxt++;
1819 l->stats.recv_pkts++;
1820
1821 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1822 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1823 else if (!tipc_data_input(l, skb, l->inputq))
1824 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1825 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1826 rc |= tipc_link_build_state_msg(l, xmitq);
1827 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1828 break;
1829 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1830
1831 /* Forward queues and wake up waiting users */
1832 if (released) {
1833 tipc_link_update_cwin(l, released, 0);
1834 tipc_link_advance_backlog(l, xmitq);
1835 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1836 link_prepare_wakeup(l);
1837 }
1838 return rc;
1839}
1840
1841static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1842 bool probe_reply, u16 rcvgap,
1843 int tolerance, int priority,
1844 struct sk_buff_head *xmitq)
1845{
1846 struct tipc_mon_state *mstate = &l->mon_state;
1847 struct sk_buff_head *dfq = &l->deferdq;
1848 struct tipc_link *bcl = l->bc_rcvlink;
1849 struct tipc_msg *hdr;
1850 struct sk_buff *skb;
1851 bool node_up = link_is_up(bcl);
1852 u16 glen = 0, bc_rcvgap = 0;
1853 int dlen = 0;
1854 void *data;
1855
1856 /* Don't send protocol message during reset or link failover */
1857 if (tipc_link_is_blocked(l))
1858 return;
1859
1860 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1861 return;
1862
1863 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1864 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1865
1866 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1867 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1868 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1869 if (!skb)
1870 return;
1871
1872 hdr = buf_msg(skb);
1873 data = msg_data(hdr);
1874 msg_set_session(hdr, l->session);
1875 msg_set_bearer_id(hdr, l->bearer_id);
1876 msg_set_net_plane(hdr, l->net_plane);
1877 msg_set_next_sent(hdr, l->snd_nxt);
1878 msg_set_ack(hdr, l->rcv_nxt - 1);
1879 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1880 msg_set_bc_ack_invalid(hdr, !node_up);
1881 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1882 msg_set_link_tolerance(hdr, tolerance);
1883 msg_set_linkprio(hdr, priority);
1884 msg_set_redundant_link(hdr, node_up);
1885 msg_set_seq_gap(hdr, 0);
1886 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1887
1888 if (mtyp == STATE_MSG) {
1889 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1890 msg_set_seqno(hdr, l->snd_nxt_state++);
1891 msg_set_seq_gap(hdr, rcvgap);
1892 bc_rcvgap = link_bc_rcv_gap(bcl);
1893 msg_set_bc_gap(hdr, bc_rcvgap);
1894 msg_set_probe(hdr, probe);
1895 msg_set_is_keepalive(hdr, probe || probe_reply);
1896 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1897 glen = tipc_build_gap_ack_blks(l, hdr);
1898 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1899 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1900 skb_trim(skb, INT_H_SIZE + glen + dlen);
1901 l->stats.sent_states++;
1902 l->rcv_unacked = 0;
1903 } else {
1904 /* RESET_MSG or ACTIVATE_MSG */
1905 if (mtyp == ACTIVATE_MSG) {
1906 msg_set_dest_session_valid(hdr, 1);
1907 msg_set_dest_session(hdr, l->peer_session);
1908 }
1909 msg_set_max_pkt(hdr, l->advertised_mtu);
1910 strcpy(data, l->if_name);
1911 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1912 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1913 }
1914 if (probe)
1915 l->stats.sent_probes++;
1916 if (rcvgap)
1917 l->stats.sent_nacks++;
1918 if (bc_rcvgap)
1919 bcl->stats.sent_nacks++;
1920 skb->priority = TC_PRIO_CONTROL;
1921 __skb_queue_tail(xmitq, skb);
1922 trace_tipc_proto_build(skb, false, l->name);
1923}
1924
1925void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1926 struct sk_buff_head *xmitq)
1927{
1928 u32 onode = tipc_own_addr(l->net);
1929 struct tipc_msg *hdr, *ihdr;
1930 struct sk_buff_head tnlq;
1931 struct sk_buff *skb;
1932 u32 dnode = l->addr;
1933
1934 __skb_queue_head_init(&tnlq);
1935 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1936 INT_H_SIZE, BASIC_H_SIZE,
1937 dnode, onode, 0, 0, 0);
1938 if (!skb) {
1939 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1940 return;
1941 }
1942
1943 hdr = buf_msg(skb);
1944 msg_set_msgcnt(hdr, 1);
1945 msg_set_bearer_id(hdr, l->peer_bearer_id);
1946
1947 ihdr = (struct tipc_msg *)msg_data(hdr);
1948 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1949 BASIC_H_SIZE, dnode);
1950 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1951 __skb_queue_tail(&tnlq, skb);
1952 tipc_link_xmit(l, &tnlq, xmitq);
1953}
1954
1955/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1956 * with contents of the link's transmit and backlog queues.
1957 */
1958void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1959 int mtyp, struct sk_buff_head *xmitq)
1960{
1961 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1962 struct sk_buff *skb, *tnlskb;
1963 struct tipc_msg *hdr, tnlhdr;
1964 struct sk_buff_head *queue = &l->transmq;
1965 struct sk_buff_head tmpxq, tnlq, frags;
1966 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1967 bool pktcnt_need_update = false;
1968 u16 syncpt;
1969 int rc;
1970
1971 if (!tnl)
1972 return;
1973
1974 __skb_queue_head_init(&tnlq);
1975 /* Link Synching:
1976 * From now on, send only one single ("dummy") SYNCH message
1977 * to peer. The SYNCH message does not contain any data, just
1978 * a header conveying the synch point to the peer.
1979 */
1980 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1981 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1982 INT_H_SIZE, 0, l->addr,
1983 tipc_own_addr(l->net),
1984 0, 0, 0);
1985 if (!tnlskb) {
1986 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1987 link_co_err);
1988 return;
1989 }
1990
1991 hdr = buf_msg(tnlskb);
1992 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1993 msg_set_syncpt(hdr, syncpt);
1994 msg_set_bearer_id(hdr, l->peer_bearer_id);
1995 __skb_queue_tail(&tnlq, tnlskb);
1996 tipc_link_xmit(tnl, &tnlq, xmitq);
1997 return;
1998 }
1999
2000 __skb_queue_head_init(&tmpxq);
2001 __skb_queue_head_init(&frags);
2002 /* At least one packet required for safe algorithm => add dummy */
2003 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
2004 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
2005 0, 0, TIPC_ERR_NO_PORT);
2006 if (!skb) {
2007 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2008 return;
2009 }
2010 __skb_queue_tail(&tnlq, skb);
2011 tipc_link_xmit(l, &tnlq, &tmpxq);
2012 __skb_queue_purge(&tmpxq);
2013
2014 /* Initialize reusable tunnel packet header */
2015 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2016 mtyp, INT_H_SIZE, l->addr);
2017 if (mtyp == SYNCH_MSG)
2018 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2019 else
2020 pktcnt = skb_queue_len(&l->transmq);
2021 pktcnt += skb_queue_len(&l->backlogq);
2022 msg_set_msgcnt(&tnlhdr, pktcnt);
2023 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2024tnl:
2025 /* Wrap each packet into a tunnel packet */
2026 skb_queue_walk(queue, skb) {
2027 hdr = buf_msg(skb);
2028 if (queue == &l->backlogq)
2029 msg_set_seqno(hdr, seqno++);
2030 pktlen = msg_size(hdr);
2031
2032 /* Tunnel link MTU is not large enough? This could be
2033 * due to:
2034 * 1) Link MTU has just changed or set differently;
2035 * 2) Or FAILOVER on the top of a SYNCH message
2036 *
2037 * The 2nd case should not happen if peer supports
2038 * TIPC_TUNNEL_ENHANCED
2039 */
2040 if (pktlen > tnl->mtu - INT_H_SIZE) {
2041 if (mtyp == FAILOVER_MSG &&
2042 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2043 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2044 &frags);
2045 if (rc) {
2046 pr_warn("%sunable to frag msg: rc %d\n",
2047 link_co_err, rc);
2048 return;
2049 }
2050 pktcnt += skb_queue_len(&frags) - 1;
2051 pktcnt_need_update = true;
2052 skb_queue_splice_tail_init(&frags, &tnlq);
2053 continue;
2054 }
2055 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2056 * => Just warn it and return!
2057 */
2058 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2059 link_co_err, msg_user(hdr),
2060 msg_type(hdr), msg_size(hdr));
2061 return;
2062 }
2063
2064 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2065 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2066 if (!tnlskb) {
2067 pr_warn("%sunable to send packet\n", link_co_err);
2068 return;
2069 }
2070 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2071 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2072 __skb_queue_tail(&tnlq, tnlskb);
2073 }
2074 if (queue != &l->backlogq) {
2075 queue = &l->backlogq;
2076 goto tnl;
2077 }
2078
2079 if (pktcnt_need_update)
2080 skb_queue_walk(&tnlq, skb) {
2081 hdr = buf_msg(skb);
2082 msg_set_msgcnt(hdr, pktcnt);
2083 }
2084
2085 tipc_link_xmit(tnl, &tnlq, xmitq);
2086
2087 if (mtyp == FAILOVER_MSG) {
2088 tnl->drop_point = l->rcv_nxt;
2089 tnl->failover_reasm_skb = l->reasm_buf;
2090 l->reasm_buf = NULL;
2091
2092 /* Failover the link's deferdq */
2093 if (unlikely(!skb_queue_empty(fdefq))) {
2094 pr_warn("Link failover deferdq not empty: %d!\n",
2095 skb_queue_len(fdefq));
2096 __skb_queue_purge(fdefq);
2097 }
2098 skb_queue_splice_init(&l->deferdq, fdefq);
2099 }
2100}
2101
2102/**
2103 * tipc_link_failover_prepare() - prepare tnl for link failover
2104 *
2105 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2106 * see the tipc_node_link_failover() for details
2107 *
2108 * @l: failover link
2109 * @tnl: tunnel link
2110 * @xmitq: queue for messages to be xmited
2111 */
2112void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2113 struct sk_buff_head *xmitq)
2114{
2115 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2116
2117 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2118
2119 /* This failover link endpoint was never established before,
2120 * so it has not received anything from peer.
2121 * Otherwise, it must be a normal failover situation or the
2122 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2123 * would have to start over from scratch instead.
2124 */
2125 tnl->drop_point = 1;
2126 tnl->failover_reasm_skb = NULL;
2127
2128 /* Initiate the link's failover deferdq */
2129 if (unlikely(!skb_queue_empty(fdefq))) {
2130 pr_warn("Link failover deferdq not empty: %d!\n",
2131 skb_queue_len(fdefq));
2132 __skb_queue_purge(fdefq);
2133 }
2134}
2135
2136/* tipc_link_validate_msg(): validate message against current link state
2137 * Returns true if message should be accepted, otherwise false
2138 */
2139bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2140{
2141 u16 curr_session = l->peer_session;
2142 u16 session = msg_session(hdr);
2143 int mtyp = msg_type(hdr);
2144
2145 if (msg_user(hdr) != LINK_PROTOCOL)
2146 return true;
2147
2148 switch (mtyp) {
2149 case RESET_MSG:
2150 if (!l->in_session)
2151 return true;
2152 /* Accept only RESET with new session number */
2153 return more(session, curr_session);
2154 case ACTIVATE_MSG:
2155 if (!l->in_session)
2156 return true;
2157 /* Accept only ACTIVATE with new or current session number */
2158 return !less(session, curr_session);
2159 case STATE_MSG:
2160 /* Accept only STATE with current session number */
2161 if (!l->in_session)
2162 return false;
2163 if (session != curr_session)
2164 return false;
2165 /* Extra sanity check */
2166 if (!link_is_up(l) && msg_ack(hdr))
2167 return false;
2168 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2169 return true;
2170 /* Accept only STATE with new sequence number */
2171 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2172 default:
2173 return false;
2174 }
2175}
2176
2177/* tipc_link_proto_rcv(): receive link level protocol message :
2178 * Note that network plane id propagates through the network, and may
2179 * change at any time. The node with lowest numerical id determines
2180 * network plane
2181 */
2182static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2183 struct sk_buff_head *xmitq)
2184{
2185 struct tipc_msg *hdr = buf_msg(skb);
2186 struct tipc_gap_ack_blks *ga = NULL;
2187 bool reply = msg_probe(hdr), retransmitted = false;
2188 u32 dlen = msg_data_sz(hdr), glen = 0, msg_max;
2189 u16 peers_snd_nxt = msg_next_sent(hdr);
2190 u16 peers_tol = msg_link_tolerance(hdr);
2191 u16 peers_prio = msg_linkprio(hdr);
2192 u16 gap = msg_seq_gap(hdr);
2193 u16 ack = msg_ack(hdr);
2194 u16 rcv_nxt = l->rcv_nxt;
2195 u16 rcvgap = 0;
2196 int mtyp = msg_type(hdr);
2197 int rc = 0, released;
2198 char *if_name;
2199 void *data;
2200
2201 trace_tipc_proto_rcv(skb, false, l->name);
2202
2203 if (dlen > U16_MAX)
2204 goto exit;
2205
2206 if (tipc_link_is_blocked(l) || !xmitq)
2207 goto exit;
2208
2209 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2210 l->net_plane = msg_net_plane(hdr);
2211
2212 if (skb_linearize(skb))
2213 goto exit;
2214
2215 hdr = buf_msg(skb);
2216 data = msg_data(hdr);
2217
2218 if (!tipc_link_validate_msg(l, hdr)) {
2219 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2220 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2221 goto exit;
2222 }
2223
2224 switch (mtyp) {
2225 case RESET_MSG:
2226 case ACTIVATE_MSG:
2227 msg_max = msg_max_pkt(hdr);
2228 if (msg_max < tipc_bearer_min_mtu(l->net, l->bearer_id))
2229 break;
2230 /* Complete own link name with peer's interface name */
2231 if_name = strrchr(l->name, ':') + 1;
2232 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2233 break;
2234 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2235 break;
2236 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2237
2238 /* Update own tolerance if peer indicates a non-zero value */
2239 if (tipc_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 priority if peer's priority is higher */
2244 if (tipc_in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2245 l->priority = peers_prio;
2246
2247 /* If peer is going down we want full re-establish cycle */
2248 if (msg_peer_stopping(hdr)) {
2249 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2250 break;
2251 }
2252
2253 /* If this endpoint was re-created while peer was ESTABLISHING
2254 * it doesn't know current session number. Force re-synch.
2255 */
2256 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2257 l->session != msg_dest_session(hdr)) {
2258 if (less(l->session, msg_dest_session(hdr)))
2259 l->session = msg_dest_session(hdr) + 1;
2260 break;
2261 }
2262
2263 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2264 if (mtyp == RESET_MSG || !link_is_up(l))
2265 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2266
2267 /* ACTIVATE_MSG takes up link if it was already locally reset */
2268 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2269 rc = TIPC_LINK_UP_EVT;
2270
2271 l->peer_session = msg_session(hdr);
2272 l->in_session = true;
2273 l->peer_bearer_id = msg_bearer_id(hdr);
2274 if (l->mtu > msg_max)
2275 l->mtu = msg_max;
2276 break;
2277
2278 case STATE_MSG:
2279 /* Validate Gap ACK blocks, drop if invalid */
2280 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2281 if (glen > dlen)
2282 break;
2283
2284 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2285
2286 /* Update own tolerance if peer indicates a non-zero value */
2287 if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2288 l->tolerance = peers_tol;
2289 l->bc_rcvlink->tolerance = peers_tol;
2290 }
2291 /* Update own prio if peer indicates a different value */
2292 if ((peers_prio != l->priority) &&
2293 tipc_in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2294 l->priority = peers_prio;
2295 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2296 }
2297
2298 l->silent_intv_cnt = 0;
2299 l->stats.recv_states++;
2300 if (msg_probe(hdr))
2301 l->stats.recv_probes++;
2302
2303 if (!link_is_up(l)) {
2304 if (l->state == LINK_ESTABLISHING)
2305 rc = TIPC_LINK_UP_EVT;
2306 break;
2307 }
2308
2309 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2310 &l->mon_state, l->bearer_id);
2311
2312 /* Send NACK if peer has sent pkts we haven't received yet */
2313 if ((reply || msg_is_keepalive(hdr)) &&
2314 more(peers_snd_nxt, rcv_nxt) &&
2315 !tipc_link_is_synching(l) &&
2316 skb_queue_empty(&l->deferdq))
2317 rcvgap = peers_snd_nxt - l->rcv_nxt;
2318 if (rcvgap || reply)
2319 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2320 rcvgap, 0, 0, xmitq);
2321
2322 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2323 &retransmitted, &rc);
2324 if (gap)
2325 l->stats.recv_nacks++;
2326 if (released || retransmitted)
2327 tipc_link_update_cwin(l, released, retransmitted);
2328 if (released)
2329 tipc_link_advance_backlog(l, xmitq);
2330 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2331 link_prepare_wakeup(l);
2332 }
2333exit:
2334 kfree_skb(skb);
2335 return rc;
2336}
2337
2338/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2339 */
2340static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2341 u16 peers_snd_nxt,
2342 struct sk_buff_head *xmitq)
2343{
2344 struct sk_buff *skb;
2345 struct tipc_msg *hdr;
2346 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2347 u16 ack = l->rcv_nxt - 1;
2348 u16 gap_to = peers_snd_nxt - 1;
2349
2350 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2351 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2352 if (!skb)
2353 return false;
2354 hdr = buf_msg(skb);
2355 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2356 msg_set_bcast_ack(hdr, ack);
2357 msg_set_bcgap_after(hdr, ack);
2358 if (dfrd_skb)
2359 gap_to = buf_seqno(dfrd_skb) - 1;
2360 msg_set_bcgap_to(hdr, gap_to);
2361 msg_set_non_seq(hdr, bcast);
2362 __skb_queue_tail(xmitq, skb);
2363 return true;
2364}
2365
2366/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2367 *
2368 * Give a newly added peer node the sequence number where it should
2369 * start receiving and acking broadcast packets.
2370 */
2371static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2372 struct sk_buff_head *xmitq)
2373{
2374 struct sk_buff_head list;
2375
2376 __skb_queue_head_init(&list);
2377 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2378 return;
2379 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2380 tipc_link_xmit(l, &list, xmitq);
2381}
2382
2383/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2384 */
2385void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2386{
2387 int mtyp = msg_type(hdr);
2388 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2389
2390 if (link_is_up(l))
2391 return;
2392
2393 if (msg_user(hdr) == BCAST_PROTOCOL) {
2394 l->rcv_nxt = peers_snd_nxt;
2395 l->state = LINK_ESTABLISHED;
2396 return;
2397 }
2398
2399 if (l->peer_caps & TIPC_BCAST_SYNCH)
2400 return;
2401
2402 if (msg_peer_node_is_up(hdr))
2403 return;
2404
2405 /* Compatibility: accept older, less safe initial synch data */
2406 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2407 l->rcv_nxt = peers_snd_nxt;
2408}
2409
2410/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2411 */
2412int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2413 struct sk_buff_head *xmitq)
2414{
2415 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2416 int rc = 0;
2417
2418 if (!link_is_up(l))
2419 return rc;
2420
2421 if (!msg_peer_node_is_up(hdr))
2422 return rc;
2423
2424 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2425 if (msg_ack(hdr))
2426 l->bc_peer_is_up = true;
2427
2428 if (!l->bc_peer_is_up)
2429 return rc;
2430
2431 /* Ignore if peers_snd_nxt goes beyond receive window */
2432 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2433 return rc;
2434
2435 l->snd_nxt = peers_snd_nxt;
2436 if (link_bc_rcv_gap(l))
2437 rc |= TIPC_LINK_SND_STATE;
2438
2439 /* Return now if sender supports nack via STATE messages */
2440 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2441 return rc;
2442
2443 /* Otherwise, be backwards compatible */
2444
2445 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2446 l->nack_state = BC_NACK_SND_CONDITIONAL;
2447 return 0;
2448 }
2449
2450 /* Don't NACK if one was recently sent or peeked */
2451 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2452 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2453 return 0;
2454 }
2455
2456 /* Conditionally delay NACK sending until next synch rcv */
2457 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2458 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2459 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2460 return 0;
2461 }
2462
2463 /* Send NACK now but suppress next one */
2464 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2465 l->nack_state = BC_NACK_SND_SUPPRESS;
2466 return 0;
2467}
2468
2469int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2470 struct tipc_gap_ack_blks *ga,
2471 struct sk_buff_head *xmitq,
2472 struct sk_buff_head *retrq)
2473{
2474 struct tipc_link *l = r->bc_sndlink;
2475 bool unused = false;
2476 int rc = 0;
2477
2478 if (!link_is_up(r) || !r->bc_peer_is_up)
2479 return 0;
2480
2481 if (gap) {
2482 l->stats.recv_nacks++;
2483 r->stats.recv_nacks++;
2484 }
2485
2486 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2487 return 0;
2488
2489 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2490 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2491
2492 tipc_link_advance_backlog(l, xmitq);
2493 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2494 link_prepare_wakeup(l);
2495
2496 return rc;
2497}
2498
2499/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2500 * This function is here for backwards compatibility, since
2501 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2502 */
2503int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2504 struct sk_buff_head *xmitq)
2505{
2506 struct tipc_msg *hdr = buf_msg(skb);
2507 u32 dnode = msg_destnode(hdr);
2508 int mtyp = msg_type(hdr);
2509 u16 acked = msg_bcast_ack(hdr);
2510 u16 from = acked + 1;
2511 u16 to = msg_bcgap_to(hdr);
2512 u16 peers_snd_nxt = to + 1;
2513 int rc = 0;
2514
2515 kfree_skb(skb);
2516
2517 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2518 return 0;
2519
2520 if (mtyp != STATE_MSG)
2521 return 0;
2522
2523 if (dnode == tipc_own_addr(l->net)) {
2524 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2525 xmitq);
2526 l->stats.recv_nacks++;
2527 return rc;
2528 }
2529
2530 /* Msg for other node => suppress own NACK at next sync if applicable */
2531 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2532 l->nack_state = BC_NACK_SND_SUPPRESS;
2533
2534 return 0;
2535}
2536
2537void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2538{
2539 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2540
2541 l->min_win = min_win;
2542 l->ssthresh = max_win;
2543 l->max_win = max_win;
2544 l->window = min_win;
2545 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2546 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2547 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2548 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2549 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2550}
2551
2552/**
2553 * tipc_link_reset_stats - reset link statistics
2554 * @l: pointer to link
2555 */
2556void tipc_link_reset_stats(struct tipc_link *l)
2557{
2558 memset(&l->stats, 0, sizeof(l->stats));
2559}
2560
2561static void link_print(struct tipc_link *l, const char *str)
2562{
2563 struct sk_buff *hskb = skb_peek(&l->transmq);
2564 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2565 u16 tail = l->snd_nxt - 1;
2566
2567 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2568 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2569 skb_queue_len(&l->transmq), head, tail,
2570 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2571}
2572
2573/* Parse and validate nested (link) properties valid for media, bearer and link
2574 */
2575int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2576{
2577 int err;
2578
2579 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2580 tipc_nl_prop_policy, NULL);
2581 if (err)
2582 return err;
2583
2584 if (props[TIPC_NLA_PROP_PRIO]) {
2585 u32 prio;
2586
2587 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2588 if (prio > TIPC_MAX_LINK_PRI)
2589 return -EINVAL;
2590 }
2591
2592 if (props[TIPC_NLA_PROP_TOL]) {
2593 u32 tol;
2594
2595 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2596 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2597 return -EINVAL;
2598 }
2599
2600 if (props[TIPC_NLA_PROP_WIN]) {
2601 u32 max_win;
2602
2603 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2604 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2605 return -EINVAL;
2606 }
2607
2608 return 0;
2609}
2610
2611static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2612{
2613 int i;
2614 struct nlattr *stats;
2615
2616 struct nla_map {
2617 u32 key;
2618 u32 val;
2619 };
2620
2621 struct nla_map map[] = {
2622 {TIPC_NLA_STATS_RX_INFO, 0},
2623 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2624 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2625 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2626 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2627 {TIPC_NLA_STATS_TX_INFO, 0},
2628 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2629 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2630 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2631 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2632 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2633 s->msg_length_counts : 1},
2634 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2635 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2636 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2637 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2638 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2639 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2640 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2641 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2642 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2643 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2644 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2645 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2646 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2647 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2648 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2649 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2650 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2651 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2652 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2653 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2654 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2655 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2656 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2657 };
2658
2659 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2660 if (!stats)
2661 return -EMSGSIZE;
2662
2663 for (i = 0; i < ARRAY_SIZE(map); i++)
2664 if (nla_put_u32(skb, map[i].key, map[i].val))
2665 goto msg_full;
2666
2667 nla_nest_end(skb, stats);
2668
2669 return 0;
2670msg_full:
2671 nla_nest_cancel(skb, stats);
2672
2673 return -EMSGSIZE;
2674}
2675
2676/* Caller should hold appropriate locks to protect the link */
2677int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2678 struct tipc_link *link, int nlflags)
2679{
2680 u32 self = tipc_own_addr(net);
2681 struct nlattr *attrs;
2682 struct nlattr *prop;
2683 void *hdr;
2684 int err;
2685
2686 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2687 nlflags, TIPC_NL_LINK_GET);
2688 if (!hdr)
2689 return -EMSGSIZE;
2690
2691 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2692 if (!attrs)
2693 goto msg_full;
2694
2695 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2696 goto attr_msg_full;
2697 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2698 goto attr_msg_full;
2699 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2700 goto attr_msg_full;
2701 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2702 goto attr_msg_full;
2703 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2704 goto attr_msg_full;
2705
2706 if (tipc_link_is_up(link))
2707 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2708 goto attr_msg_full;
2709 if (link->active)
2710 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2711 goto attr_msg_full;
2712
2713 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2714 if (!prop)
2715 goto attr_msg_full;
2716 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2717 goto prop_msg_full;
2718 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2719 goto prop_msg_full;
2720 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2721 link->window))
2722 goto prop_msg_full;
2723 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2724 goto prop_msg_full;
2725 nla_nest_end(msg->skb, prop);
2726
2727 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2728 if (err)
2729 goto attr_msg_full;
2730
2731 nla_nest_end(msg->skb, attrs);
2732 genlmsg_end(msg->skb, hdr);
2733
2734 return 0;
2735
2736prop_msg_full:
2737 nla_nest_cancel(msg->skb, prop);
2738attr_msg_full:
2739 nla_nest_cancel(msg->skb, attrs);
2740msg_full:
2741 genlmsg_cancel(msg->skb, hdr);
2742
2743 return -EMSGSIZE;
2744}
2745
2746static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2747 struct tipc_stats *stats)
2748{
2749 int i;
2750 struct nlattr *nest;
2751
2752 struct nla_map {
2753 __u32 key;
2754 __u32 val;
2755 };
2756
2757 struct nla_map map[] = {
2758 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2759 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2760 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2761 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2762 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2763 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2764 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2765 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2766 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2767 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2768 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2769 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2770 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2771 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2772 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2773 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2774 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2775 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2776 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2777 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2778 };
2779
2780 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2781 if (!nest)
2782 return -EMSGSIZE;
2783
2784 for (i = 0; i < ARRAY_SIZE(map); i++)
2785 if (nla_put_u32(skb, map[i].key, map[i].val))
2786 goto msg_full;
2787
2788 nla_nest_end(skb, nest);
2789
2790 return 0;
2791msg_full:
2792 nla_nest_cancel(skb, nest);
2793
2794 return -EMSGSIZE;
2795}
2796
2797int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2798 struct tipc_link *bcl)
2799{
2800 int err;
2801 void *hdr;
2802 struct nlattr *attrs;
2803 struct nlattr *prop;
2804 u32 bc_mode = tipc_bcast_get_mode(net);
2805 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2806
2807 if (!bcl)
2808 return 0;
2809
2810 tipc_bcast_lock(net);
2811
2812 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2813 NLM_F_MULTI, TIPC_NL_LINK_GET);
2814 if (!hdr) {
2815 tipc_bcast_unlock(net);
2816 return -EMSGSIZE;
2817 }
2818
2819 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2820 if (!attrs)
2821 goto msg_full;
2822
2823 /* The broadcast link is always up */
2824 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2825 goto attr_msg_full;
2826
2827 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2828 goto attr_msg_full;
2829 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2830 goto attr_msg_full;
2831 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2832 goto attr_msg_full;
2833 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2834 goto attr_msg_full;
2835
2836 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2837 if (!prop)
2838 goto attr_msg_full;
2839 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2840 goto prop_msg_full;
2841 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2842 goto prop_msg_full;
2843 if (bc_mode & BCLINK_MODE_SEL)
2844 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2845 bc_ratio))
2846 goto prop_msg_full;
2847 nla_nest_end(msg->skb, prop);
2848
2849 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2850 if (err)
2851 goto attr_msg_full;
2852
2853 tipc_bcast_unlock(net);
2854 nla_nest_end(msg->skb, attrs);
2855 genlmsg_end(msg->skb, hdr);
2856
2857 return 0;
2858
2859prop_msg_full:
2860 nla_nest_cancel(msg->skb, prop);
2861attr_msg_full:
2862 nla_nest_cancel(msg->skb, attrs);
2863msg_full:
2864 tipc_bcast_unlock(net);
2865 genlmsg_cancel(msg->skb, hdr);
2866
2867 return -EMSGSIZE;
2868}
2869
2870void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2871 struct sk_buff_head *xmitq)
2872{
2873 l->tolerance = tol;
2874 if (l->bc_rcvlink)
2875 l->bc_rcvlink->tolerance = tol;
2876 if (link_is_up(l))
2877 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2878}
2879
2880void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2881 struct sk_buff_head *xmitq)
2882{
2883 l->priority = prio;
2884 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2885}
2886
2887void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2888{
2889 l->abort_limit = limit;
2890}
2891
2892/**
2893 * tipc_link_dump - dump TIPC link data
2894 * @l: tipc link to be dumped
2895 * @dqueues: bitmask to decide if any link queue to be dumped?
2896 * - TIPC_DUMP_NONE: don't dump link queues
2897 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2898 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2899 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2900 * - TIPC_DUMP_INPUTQ: dump link input queue
2901 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2902 * - TIPC_DUMP_ALL: dump all the link queues above
2903 * @buf: returned buffer of dump data in format
2904 */
2905int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2906{
2907 int i = 0;
2908 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2909 struct sk_buff_head *list;
2910 struct sk_buff *hskb, *tskb;
2911 u32 len;
2912
2913 if (!l) {
2914 i += scnprintf(buf, sz, "link data: (null)\n");
2915 return i;
2916 }
2917
2918 i += scnprintf(buf, sz, "link data: %x", l->addr);
2919 i += scnprintf(buf + i, sz - i, " %x", l->state);
2920 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2921 i += scnprintf(buf + i, sz - i, " %u", l->session);
2922 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2923 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2924 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2925 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2926 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2927 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2928 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2929 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2930 i += scnprintf(buf + i, sz - i, " %u", 0);
2931 i += scnprintf(buf + i, sz - i, " %u", 0);
2932 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2933
2934 list = &l->transmq;
2935 len = skb_queue_len(list);
2936 hskb = skb_peek(list);
2937 tskb = skb_peek_tail(list);
2938 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2939 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2940 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2941
2942 list = &l->deferdq;
2943 len = skb_queue_len(list);
2944 hskb = skb_peek(list);
2945 tskb = skb_peek_tail(list);
2946 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2947 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2948 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2949
2950 list = &l->backlogq;
2951 len = skb_queue_len(list);
2952 hskb = skb_peek(list);
2953 tskb = skb_peek_tail(list);
2954 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2955 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2956 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2957
2958 list = l->inputq;
2959 len = skb_queue_len(list);
2960 hskb = skb_peek(list);
2961 tskb = skb_peek_tail(list);
2962 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2963 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2964 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2965
2966 if (dqueues & TIPC_DUMP_TRANSMQ) {
2967 i += scnprintf(buf + i, sz - i, "transmq: ");
2968 i += tipc_list_dump(&l->transmq, false, buf + i);
2969 }
2970 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2971 i += scnprintf(buf + i, sz - i,
2972 "backlogq: <%u %u %u %u %u>, ",
2973 l->backlog[TIPC_LOW_IMPORTANCE].len,
2974 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2975 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2976 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2977 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2978 i += tipc_list_dump(&l->backlogq, false, buf + i);
2979 }
2980 if (dqueues & TIPC_DUMP_DEFERDQ) {
2981 i += scnprintf(buf + i, sz - i, "deferdq: ");
2982 i += tipc_list_dump(&l->deferdq, false, buf + i);
2983 }
2984 if (dqueues & TIPC_DUMP_INPUTQ) {
2985 i += scnprintf(buf + i, sz - i, "inputq: ");
2986 i += tipc_list_dump(l->inputq, false, buf + i);
2987 }
2988 if (dqueues & TIPC_DUMP_WAKEUP) {
2989 i += scnprintf(buf + i, sz - i, "wakeup: ");
2990 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2991 }
2992
2993 return i;
2994}