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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 * @net: pointer to namespace struct
86 * @peer_session: link session # being used by peer end of link
87 * @peer_bearer_id: bearer id used by link's peer endpoint
88 * @bearer_id: local bearer id used by link
89 * @tolerance: minimum link continuity loss needed to reset link [in ms]
90 * @abort_limit: # of unacknowledged continuity probes needed to reset link
91 * @state: current state of link FSM
92 * @peer_caps: bitmap describing capabilities of peer node
93 * @silent_intv_cnt: # of timer intervals without any reception from peer
94 * @priority: current link priority
95 * @net_plane: current link network plane ('A' through 'H')
96 * @mon_state: cookie with information needed by link monitor
97 * @mtu: current maximum packet size for this link
98 * @advertised_mtu: advertised own mtu when link is being established
99 * @backlogq: queue for messages waiting to be sent
100 * @ackers: # of peers that needs to ack each packet before it can be released
101 * @acked: # last packet acked by a certain peer. Used for broadcast.
102 * @rcv_nxt: next sequence number to expect for inbound messages
103 * @inputq: buffer queue for messages to be delivered upwards
104 * @namedq: buffer queue for name table messages to be delivered upwards
105 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
106 * @reasm_buf: head of partially reassembled inbound message fragments
107 * @stats: collects statistics regarding link activity
108 * @session: session to be used by link
109 * @snd_nxt_state: next send seq number
110 * @rcv_nxt_state: next rcv seq number
111 * @in_session: have received ACTIVATE_MSG from peer
112 * @active: link is active
113 * @if_name: associated interface name
114 * @rst_cnt: link reset counter
115 * @drop_point: seq number for failover handling (FIXME)
116 * @failover_reasm_skb: saved failover msg ptr (FIXME)
117 * @failover_deferdq: deferred message queue for failover processing (FIXME)
118 * @transmq: the link's transmit queue
119 * @backlog: link's backlog by priority (importance)
120 * @snd_nxt: next sequence number to be used
121 * @rcv_unacked: # messages read by user, but not yet acked back to peer
122 * @deferdq: deferred receive queue
123 * @window: sliding window size for congestion handling
124 * @min_win: minimal send window to be used by link
125 * @ssthresh: slow start threshold for congestion handling
126 * @max_win: maximal send window to be used by link
127 * @cong_acks: congestion acks for congestion avoidance (FIXME)
128 * @checkpoint: seq number for congestion window size handling
129 * @reasm_tnlmsg: fragmentation/reassembly area for tunnel protocol message
130 * @last_gap: last gap ack blocks for bcast (FIXME)
131 * @last_ga: ptr to gap ack blocks
132 * @bc_rcvlink: the peer specific link used for broadcast reception
133 * @bc_sndlink: the namespace global link used for broadcast sending
134 * @nack_state: bcast nack state
135 * @bc_peer_is_up: peer has acked the bcast init msg
136 */
137struct tipc_link {
138 u32 addr;
139 char name[TIPC_MAX_LINK_NAME];
140 struct net *net;
141
142 /* Management and link supervision data */
143 u16 peer_session;
144 u16 session;
145 u16 snd_nxt_state;
146 u16 rcv_nxt_state;
147 u32 peer_bearer_id;
148 u32 bearer_id;
149 u32 tolerance;
150 u32 abort_limit;
151 u32 state;
152 u16 peer_caps;
153 bool in_session;
154 bool active;
155 u32 silent_intv_cnt;
156 char if_name[TIPC_MAX_IF_NAME];
157 u32 priority;
158 char net_plane;
159 struct tipc_mon_state mon_state;
160 u16 rst_cnt;
161
162 /* Failover/synch */
163 u16 drop_point;
164 struct sk_buff *failover_reasm_skb;
165 struct sk_buff_head failover_deferdq;
166
167 /* Max packet negotiation */
168 u16 mtu;
169 u16 advertised_mtu;
170
171 /* Sending */
172 struct sk_buff_head transmq;
173 struct sk_buff_head backlogq;
174 struct {
175 u16 len;
176 u16 limit;
177 struct sk_buff *target_bskb;
178 } backlog[5];
179 u16 snd_nxt;
180
181 /* Reception */
182 u16 rcv_nxt;
183 u32 rcv_unacked;
184 struct sk_buff_head deferdq;
185 struct sk_buff_head *inputq;
186 struct sk_buff_head *namedq;
187
188 /* Congestion handling */
189 struct sk_buff_head wakeupq;
190 u16 window;
191 u16 min_win;
192 u16 ssthresh;
193 u16 max_win;
194 u16 cong_acks;
195 u16 checkpoint;
196
197 /* Fragmentation/reassembly */
198 struct sk_buff *reasm_buf;
199 struct sk_buff *reasm_tnlmsg;
200
201 /* Broadcast */
202 u16 ackers;
203 u16 acked;
204 u16 last_gap;
205 struct tipc_gap_ack_blks *last_ga;
206 struct tipc_link *bc_rcvlink;
207 struct tipc_link *bc_sndlink;
208 u8 nack_state;
209 bool bc_peer_is_up;
210
211 /* Statistics */
212 struct tipc_stats stats;
213};
214
215/*
216 * Error message prefixes
217 */
218static const char *link_co_err = "Link tunneling error, ";
219static const char *link_rst_msg = "Resetting link ";
220
221/* Send states for broadcast NACKs
222 */
223enum {
224 BC_NACK_SND_CONDITIONAL,
225 BC_NACK_SND_UNCONDITIONAL,
226 BC_NACK_SND_SUPPRESS,
227};
228
229#define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
230#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
231
232/* Link FSM states:
233 */
234enum {
235 LINK_ESTABLISHED = 0xe,
236 LINK_ESTABLISHING = 0xe << 4,
237 LINK_RESET = 0x1 << 8,
238 LINK_RESETTING = 0x2 << 12,
239 LINK_PEER_RESET = 0xd << 16,
240 LINK_FAILINGOVER = 0xf << 20,
241 LINK_SYNCHING = 0xc << 24
242};
243
244static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
245 struct sk_buff_head *xmitq);
246static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
247 bool probe_reply, u16 rcvgap,
248 int tolerance, int priority,
249 struct sk_buff_head *xmitq);
250static void link_print(struct tipc_link *l, const char *str);
251static int tipc_link_build_nack_msg(struct tipc_link *l,
252 struct sk_buff_head *xmitq);
253static void tipc_link_build_bc_init_msg(struct tipc_link *l,
254 struct sk_buff_head *xmitq);
255static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
256 struct tipc_link *l, u8 start_index);
257static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
258static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
259 u16 acked, u16 gap,
260 struct tipc_gap_ack_blks *ga,
261 struct sk_buff_head *xmitq,
262 bool *retransmitted, int *rc);
263static void tipc_link_update_cwin(struct tipc_link *l, int released,
264 bool retransmitted);
265/*
266 * Simple non-static link routines (i.e. referenced outside this file)
267 */
268bool tipc_link_is_up(struct tipc_link *l)
269{
270 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
271}
272
273bool tipc_link_peer_is_down(struct tipc_link *l)
274{
275 return l->state == LINK_PEER_RESET;
276}
277
278bool tipc_link_is_reset(struct tipc_link *l)
279{
280 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
281}
282
283bool tipc_link_is_establishing(struct tipc_link *l)
284{
285 return l->state == LINK_ESTABLISHING;
286}
287
288bool tipc_link_is_synching(struct tipc_link *l)
289{
290 return l->state == LINK_SYNCHING;
291}
292
293bool tipc_link_is_failingover(struct tipc_link *l)
294{
295 return l->state == LINK_FAILINGOVER;
296}
297
298bool tipc_link_is_blocked(struct tipc_link *l)
299{
300 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
301}
302
303static bool link_is_bc_sndlink(struct tipc_link *l)
304{
305 return !l->bc_sndlink;
306}
307
308static bool link_is_bc_rcvlink(struct tipc_link *l)
309{
310 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
311}
312
313void tipc_link_set_active(struct tipc_link *l, bool active)
314{
315 l->active = active;
316}
317
318u32 tipc_link_id(struct tipc_link *l)
319{
320 return l->peer_bearer_id << 16 | l->bearer_id;
321}
322
323int tipc_link_min_win(struct tipc_link *l)
324{
325 return l->min_win;
326}
327
328int tipc_link_max_win(struct tipc_link *l)
329{
330 return l->max_win;
331}
332
333int tipc_link_prio(struct tipc_link *l)
334{
335 return l->priority;
336}
337
338unsigned long tipc_link_tolerance(struct tipc_link *l)
339{
340 return l->tolerance;
341}
342
343struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
344{
345 return l->inputq;
346}
347
348char tipc_link_plane(struct tipc_link *l)
349{
350 return l->net_plane;
351}
352
353struct net *tipc_link_net(struct tipc_link *l)
354{
355 return l->net;
356}
357
358void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
359{
360 l->peer_caps = capabilities;
361}
362
363void tipc_link_add_bc_peer(struct tipc_link *snd_l,
364 struct tipc_link *uc_l,
365 struct sk_buff_head *xmitq)
366{
367 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
368
369 snd_l->ackers++;
370 rcv_l->acked = snd_l->snd_nxt - 1;
371 snd_l->state = LINK_ESTABLISHED;
372 tipc_link_build_bc_init_msg(uc_l, xmitq);
373}
374
375void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
376 struct tipc_link *rcv_l,
377 struct sk_buff_head *xmitq)
378{
379 u16 ack = snd_l->snd_nxt - 1;
380
381 snd_l->ackers--;
382 rcv_l->bc_peer_is_up = true;
383 rcv_l->state = LINK_ESTABLISHED;
384 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
385 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
386 tipc_link_reset(rcv_l);
387 rcv_l->state = LINK_RESET;
388 if (!snd_l->ackers) {
389 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
390 tipc_link_reset(snd_l);
391 snd_l->state = LINK_RESET;
392 __skb_queue_purge(xmitq);
393 }
394}
395
396int tipc_link_bc_peers(struct tipc_link *l)
397{
398 return l->ackers;
399}
400
401static u16 link_bc_rcv_gap(struct tipc_link *l)
402{
403 struct sk_buff *skb = skb_peek(&l->deferdq);
404 u16 gap = 0;
405
406 if (more(l->snd_nxt, l->rcv_nxt))
407 gap = l->snd_nxt - l->rcv_nxt;
408 if (skb)
409 gap = buf_seqno(skb) - l->rcv_nxt;
410 return gap;
411}
412
413void tipc_link_set_mtu(struct tipc_link *l, int mtu)
414{
415 l->mtu = mtu;
416}
417
418int tipc_link_mtu(struct tipc_link *l)
419{
420 return l->mtu;
421}
422
423int tipc_link_mss(struct tipc_link *l)
424{
425#ifdef CONFIG_TIPC_CRYPTO
426 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
427#else
428 return l->mtu - INT_H_SIZE;
429#endif
430}
431
432u16 tipc_link_rcv_nxt(struct tipc_link *l)
433{
434 return l->rcv_nxt;
435}
436
437u16 tipc_link_acked(struct tipc_link *l)
438{
439 return l->acked;
440}
441
442char *tipc_link_name(struct tipc_link *l)
443{
444 return l->name;
445}
446
447u32 tipc_link_state(struct tipc_link *l)
448{
449 return l->state;
450}
451
452/**
453 * tipc_link_create - create a new link
454 * @net: pointer to associated network namespace
455 * @if_name: associated interface name
456 * @bearer_id: id (index) of associated bearer
457 * @tolerance: link tolerance to be used by link
458 * @net_plane: network plane (A,B,c..) this link belongs to
459 * @mtu: mtu to be advertised by link
460 * @priority: priority to be used by link
461 * @min_win: minimal send window to be used by link
462 * @max_win: maximal send window to be used by link
463 * @session: session to be used by link
464 * @peer: node id of peer node
465 * @peer_caps: bitmap describing peer node capabilities
466 * @bc_sndlink: the namespace global link used for broadcast sending
467 * @bc_rcvlink: the peer specific link used for broadcast reception
468 * @inputq: queue to put messages ready for delivery
469 * @namedq: queue to put binding table update messages ready for delivery
470 * @link: return value, pointer to put the created link
471 * @self: local unicast link id
472 * @peer_id: 128-bit ID of peer
473 *
474 * Return: true if link was created, otherwise false
475 */
476bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
477 int tolerance, char net_plane, u32 mtu, int priority,
478 u32 min_win, u32 max_win, u32 session, u32 self,
479 u32 peer, u8 *peer_id, u16 peer_caps,
480 struct tipc_link *bc_sndlink,
481 struct tipc_link *bc_rcvlink,
482 struct sk_buff_head *inputq,
483 struct sk_buff_head *namedq,
484 struct tipc_link **link)
485{
486 char peer_str[NODE_ID_STR_LEN] = {0,};
487 char self_str[NODE_ID_STR_LEN] = {0,};
488 struct tipc_link *l;
489
490 l = kzalloc(sizeof(*l), GFP_ATOMIC);
491 if (!l)
492 return false;
493 *link = l;
494 l->session = session;
495
496 /* Set link name for unicast links only */
497 if (peer_id) {
498 tipc_nodeid2string(self_str, tipc_own_id(net));
499 if (strlen(self_str) > 16)
500 sprintf(self_str, "%x", self);
501 tipc_nodeid2string(peer_str, peer_id);
502 if (strlen(peer_str) > 16)
503 sprintf(peer_str, "%x", peer);
504 }
505 /* Peer i/f name will be completed by reset/activate message */
506 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
507 self_str, if_name, peer_str);
508
509 strcpy(l->if_name, if_name);
510 l->addr = peer;
511 l->peer_caps = peer_caps;
512 l->net = net;
513 l->in_session = false;
514 l->bearer_id = bearer_id;
515 l->tolerance = tolerance;
516 if (bc_rcvlink)
517 bc_rcvlink->tolerance = tolerance;
518 l->net_plane = net_plane;
519 l->advertised_mtu = mtu;
520 l->mtu = mtu;
521 l->priority = priority;
522 tipc_link_set_queue_limits(l, min_win, max_win);
523 l->ackers = 1;
524 l->bc_sndlink = bc_sndlink;
525 l->bc_rcvlink = bc_rcvlink;
526 l->inputq = inputq;
527 l->namedq = namedq;
528 l->state = LINK_RESETTING;
529 __skb_queue_head_init(&l->transmq);
530 __skb_queue_head_init(&l->backlogq);
531 __skb_queue_head_init(&l->deferdq);
532 __skb_queue_head_init(&l->failover_deferdq);
533 skb_queue_head_init(&l->wakeupq);
534 skb_queue_head_init(l->inputq);
535 return true;
536}
537
538/**
539 * tipc_link_bc_create - create new link to be used for broadcast
540 * @net: pointer to associated network namespace
541 * @mtu: mtu to be used initially if no peers
542 * @min_win: minimal send window to be used by link
543 * @max_win: maximal send window to be used by link
544 * @inputq: queue to put messages ready for delivery
545 * @namedq: queue to put binding table update messages ready for delivery
546 * @link: return value, pointer to put the created link
547 * @ownnode: identity of own node
548 * @peer: node id of peer node
549 * @peer_id: 128-bit ID of peer
550 * @peer_caps: bitmap describing peer node capabilities
551 * @bc_sndlink: the namespace global link used for broadcast sending
552 *
553 * Return: true if link was created, otherwise false
554 */
555bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
556 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
557 struct sk_buff_head *inputq,
558 struct sk_buff_head *namedq,
559 struct tipc_link *bc_sndlink,
560 struct tipc_link **link)
561{
562 struct tipc_link *l;
563
564 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
565 max_win, 0, ownnode, peer, NULL, peer_caps,
566 bc_sndlink, NULL, inputq, namedq, link))
567 return false;
568
569 l = *link;
570 if (peer_id) {
571 char peer_str[NODE_ID_STR_LEN] = {0,};
572
573 tipc_nodeid2string(peer_str, peer_id);
574 if (strlen(peer_str) > 16)
575 sprintf(peer_str, "%x", peer);
576 /* Broadcast receiver link name: "broadcast-link:<peer>" */
577 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
578 peer_str);
579 } else {
580 strcpy(l->name, tipc_bclink_name);
581 }
582 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
583 tipc_link_reset(l);
584 l->state = LINK_RESET;
585 l->ackers = 0;
586 l->bc_rcvlink = l;
587
588 /* Broadcast send link is always up */
589 if (link_is_bc_sndlink(l))
590 l->state = LINK_ESTABLISHED;
591
592 /* Disable replicast if even a single peer doesn't support it */
593 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
594 tipc_bcast_toggle_rcast(net, false);
595
596 return true;
597}
598
599/**
600 * tipc_link_fsm_evt - link finite state machine
601 * @l: pointer to link
602 * @evt: state machine event to be processed
603 */
604int tipc_link_fsm_evt(struct tipc_link *l, int evt)
605{
606 int rc = 0;
607 int old_state = l->state;
608
609 switch (l->state) {
610 case LINK_RESETTING:
611 switch (evt) {
612 case LINK_PEER_RESET_EVT:
613 l->state = LINK_PEER_RESET;
614 break;
615 case LINK_RESET_EVT:
616 l->state = LINK_RESET;
617 break;
618 case LINK_FAILURE_EVT:
619 case LINK_FAILOVER_BEGIN_EVT:
620 case LINK_ESTABLISH_EVT:
621 case LINK_FAILOVER_END_EVT:
622 case LINK_SYNCH_BEGIN_EVT:
623 case LINK_SYNCH_END_EVT:
624 default:
625 goto illegal_evt;
626 }
627 break;
628 case LINK_RESET:
629 switch (evt) {
630 case LINK_PEER_RESET_EVT:
631 l->state = LINK_ESTABLISHING;
632 break;
633 case LINK_FAILOVER_BEGIN_EVT:
634 l->state = LINK_FAILINGOVER;
635 break;
636 case LINK_FAILURE_EVT:
637 case LINK_RESET_EVT:
638 case LINK_ESTABLISH_EVT:
639 case LINK_FAILOVER_END_EVT:
640 break;
641 case LINK_SYNCH_BEGIN_EVT:
642 case LINK_SYNCH_END_EVT:
643 default:
644 goto illegal_evt;
645 }
646 break;
647 case LINK_PEER_RESET:
648 switch (evt) {
649 case LINK_RESET_EVT:
650 l->state = LINK_ESTABLISHING;
651 break;
652 case LINK_PEER_RESET_EVT:
653 case LINK_ESTABLISH_EVT:
654 case LINK_FAILURE_EVT:
655 break;
656 case LINK_SYNCH_BEGIN_EVT:
657 case LINK_SYNCH_END_EVT:
658 case LINK_FAILOVER_BEGIN_EVT:
659 case LINK_FAILOVER_END_EVT:
660 default:
661 goto illegal_evt;
662 }
663 break;
664 case LINK_FAILINGOVER:
665 switch (evt) {
666 case LINK_FAILOVER_END_EVT:
667 l->state = LINK_RESET;
668 break;
669 case LINK_PEER_RESET_EVT:
670 case LINK_RESET_EVT:
671 case LINK_ESTABLISH_EVT:
672 case LINK_FAILURE_EVT:
673 break;
674 case LINK_FAILOVER_BEGIN_EVT:
675 case LINK_SYNCH_BEGIN_EVT:
676 case LINK_SYNCH_END_EVT:
677 default:
678 goto illegal_evt;
679 }
680 break;
681 case LINK_ESTABLISHING:
682 switch (evt) {
683 case LINK_ESTABLISH_EVT:
684 l->state = LINK_ESTABLISHED;
685 break;
686 case LINK_FAILOVER_BEGIN_EVT:
687 l->state = LINK_FAILINGOVER;
688 break;
689 case LINK_RESET_EVT:
690 l->state = LINK_RESET;
691 break;
692 case LINK_FAILURE_EVT:
693 case LINK_PEER_RESET_EVT:
694 case LINK_SYNCH_BEGIN_EVT:
695 case LINK_FAILOVER_END_EVT:
696 break;
697 case LINK_SYNCH_END_EVT:
698 default:
699 goto illegal_evt;
700 }
701 break;
702 case LINK_ESTABLISHED:
703 switch (evt) {
704 case LINK_PEER_RESET_EVT:
705 l->state = LINK_PEER_RESET;
706 rc |= TIPC_LINK_DOWN_EVT;
707 break;
708 case LINK_FAILURE_EVT:
709 l->state = LINK_RESETTING;
710 rc |= TIPC_LINK_DOWN_EVT;
711 break;
712 case LINK_RESET_EVT:
713 l->state = LINK_RESET;
714 break;
715 case LINK_ESTABLISH_EVT:
716 case LINK_SYNCH_END_EVT:
717 break;
718 case LINK_SYNCH_BEGIN_EVT:
719 l->state = LINK_SYNCHING;
720 break;
721 case LINK_FAILOVER_BEGIN_EVT:
722 case LINK_FAILOVER_END_EVT:
723 default:
724 goto illegal_evt;
725 }
726 break;
727 case LINK_SYNCHING:
728 switch (evt) {
729 case LINK_PEER_RESET_EVT:
730 l->state = LINK_PEER_RESET;
731 rc |= TIPC_LINK_DOWN_EVT;
732 break;
733 case LINK_FAILURE_EVT:
734 l->state = LINK_RESETTING;
735 rc |= TIPC_LINK_DOWN_EVT;
736 break;
737 case LINK_RESET_EVT:
738 l->state = LINK_RESET;
739 break;
740 case LINK_ESTABLISH_EVT:
741 case LINK_SYNCH_BEGIN_EVT:
742 break;
743 case LINK_SYNCH_END_EVT:
744 l->state = LINK_ESTABLISHED;
745 break;
746 case LINK_FAILOVER_BEGIN_EVT:
747 case LINK_FAILOVER_END_EVT:
748 default:
749 goto illegal_evt;
750 }
751 break;
752 default:
753 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
754 }
755 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
756 return rc;
757illegal_evt:
758 pr_err("Illegal FSM event %x in state %x on link %s\n",
759 evt, l->state, l->name);
760 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
761 return rc;
762}
763
764/* link_profile_stats - update statistical profiling of traffic
765 */
766static void link_profile_stats(struct tipc_link *l)
767{
768 struct sk_buff *skb;
769 struct tipc_msg *msg;
770 int length;
771
772 /* Update counters used in statistical profiling of send traffic */
773 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
774 l->stats.queue_sz_counts++;
775
776 skb = skb_peek(&l->transmq);
777 if (!skb)
778 return;
779 msg = buf_msg(skb);
780 length = msg_size(msg);
781
782 if (msg_user(msg) == MSG_FRAGMENTER) {
783 if (msg_type(msg) != FIRST_FRAGMENT)
784 return;
785 length = msg_size(msg_inner_hdr(msg));
786 }
787 l->stats.msg_lengths_total += length;
788 l->stats.msg_length_counts++;
789 if (length <= 64)
790 l->stats.msg_length_profile[0]++;
791 else if (length <= 256)
792 l->stats.msg_length_profile[1]++;
793 else if (length <= 1024)
794 l->stats.msg_length_profile[2]++;
795 else if (length <= 4096)
796 l->stats.msg_length_profile[3]++;
797 else if (length <= 16384)
798 l->stats.msg_length_profile[4]++;
799 else if (length <= 32768)
800 l->stats.msg_length_profile[5]++;
801 else
802 l->stats.msg_length_profile[6]++;
803}
804
805/**
806 * tipc_link_too_silent - check if link is "too silent"
807 * @l: tipc link to be checked
808 *
809 * Return: true if the link 'silent_intv_cnt' is about to reach the
810 * 'abort_limit' value, otherwise false
811 */
812bool tipc_link_too_silent(struct tipc_link *l)
813{
814 return (l->silent_intv_cnt + 2 > l->abort_limit);
815}
816
817/* tipc_link_timeout - perform periodic task as instructed from node timeout
818 */
819int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
820{
821 int mtyp = 0;
822 int rc = 0;
823 bool state = false;
824 bool probe = false;
825 bool setup = false;
826 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
827 u16 bc_acked = l->bc_rcvlink->acked;
828 struct tipc_mon_state *mstate = &l->mon_state;
829
830 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
831 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
832 switch (l->state) {
833 case LINK_ESTABLISHED:
834 case LINK_SYNCHING:
835 mtyp = STATE_MSG;
836 link_profile_stats(l);
837 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
838 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
839 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
840 state = bc_acked != bc_snt;
841 state |= l->bc_rcvlink->rcv_unacked;
842 state |= l->rcv_unacked;
843 state |= !skb_queue_empty(&l->transmq);
844 probe = mstate->probing;
845 probe |= l->silent_intv_cnt;
846 if (probe || mstate->monitoring)
847 l->silent_intv_cnt++;
848 probe |= !skb_queue_empty(&l->deferdq);
849 if (l->snd_nxt == l->checkpoint) {
850 tipc_link_update_cwin(l, 0, 0);
851 probe = true;
852 }
853 l->checkpoint = l->snd_nxt;
854 break;
855 case LINK_RESET:
856 setup = l->rst_cnt++ <= 4;
857 setup |= !(l->rst_cnt % 16);
858 mtyp = RESET_MSG;
859 break;
860 case LINK_ESTABLISHING:
861 setup = true;
862 mtyp = ACTIVATE_MSG;
863 break;
864 case LINK_PEER_RESET:
865 case LINK_RESETTING:
866 case LINK_FAILINGOVER:
867 break;
868 default:
869 break;
870 }
871
872 if (state || probe || setup)
873 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
874
875 return rc;
876}
877
878/**
879 * link_schedule_user - schedule a message sender for wakeup after congestion
880 * @l: congested link
881 * @hdr: header of message that is being sent
882 * Create pseudo msg to send back to user when congestion abates
883 */
884static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
885{
886 u32 dnode = tipc_own_addr(l->net);
887 u32 dport = msg_origport(hdr);
888 struct sk_buff *skb;
889
890 /* Create and schedule wakeup pseudo message */
891 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
892 dnode, l->addr, dport, 0, 0);
893 if (!skb)
894 return -ENOBUFS;
895 msg_set_dest_droppable(buf_msg(skb), true);
896 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
897 skb_queue_tail(&l->wakeupq, skb);
898 l->stats.link_congs++;
899 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
900 return -ELINKCONG;
901}
902
903/**
904 * link_prepare_wakeup - prepare users for wakeup after congestion
905 * @l: congested link
906 * Wake up a number of waiting users, as permitted by available space
907 * in the send queue
908 */
909static void link_prepare_wakeup(struct tipc_link *l)
910{
911 struct sk_buff_head *wakeupq = &l->wakeupq;
912 struct sk_buff_head *inputq = l->inputq;
913 struct sk_buff *skb, *tmp;
914 struct sk_buff_head tmpq;
915 int avail[5] = {0,};
916 int imp = 0;
917
918 __skb_queue_head_init(&tmpq);
919
920 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
921 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
922
923 skb_queue_walk_safe(wakeupq, skb, tmp) {
924 imp = TIPC_SKB_CB(skb)->chain_imp;
925 if (avail[imp] <= 0)
926 continue;
927 avail[imp]--;
928 __skb_unlink(skb, wakeupq);
929 __skb_queue_tail(&tmpq, skb);
930 }
931
932 spin_lock_bh(&inputq->lock);
933 skb_queue_splice_tail(&tmpq, inputq);
934 spin_unlock_bh(&inputq->lock);
935
936}
937
938/**
939 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
940 * the given skb should be next attempted
941 * @skb: skb to set a future retransmission time for
942 * @l: link the skb will be transmitted on
943 */
944static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
945 struct tipc_link *l)
946{
947 if (link_is_bc_sndlink(l))
948 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
949 else
950 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
951}
952
953void tipc_link_reset(struct tipc_link *l)
954{
955 struct sk_buff_head list;
956 u32 imp;
957
958 __skb_queue_head_init(&list);
959
960 l->in_session = false;
961 /* Force re-synch of peer session number before establishing */
962 l->peer_session--;
963 l->session++;
964 l->mtu = l->advertised_mtu;
965
966 spin_lock_bh(&l->wakeupq.lock);
967 skb_queue_splice_init(&l->wakeupq, &list);
968 spin_unlock_bh(&l->wakeupq.lock);
969
970 spin_lock_bh(&l->inputq->lock);
971 skb_queue_splice_init(&list, l->inputq);
972 spin_unlock_bh(&l->inputq->lock);
973
974 __skb_queue_purge(&l->transmq);
975 __skb_queue_purge(&l->deferdq);
976 __skb_queue_purge(&l->backlogq);
977 __skb_queue_purge(&l->failover_deferdq);
978 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
979 l->backlog[imp].len = 0;
980 l->backlog[imp].target_bskb = NULL;
981 }
982 kfree_skb(l->reasm_buf);
983 kfree_skb(l->reasm_tnlmsg);
984 kfree_skb(l->failover_reasm_skb);
985 l->reasm_buf = NULL;
986 l->reasm_tnlmsg = NULL;
987 l->failover_reasm_skb = NULL;
988 l->rcv_unacked = 0;
989 l->snd_nxt = 1;
990 l->rcv_nxt = 1;
991 l->snd_nxt_state = 1;
992 l->rcv_nxt_state = 1;
993 l->acked = 0;
994 l->last_gap = 0;
995 kfree(l->last_ga);
996 l->last_ga = NULL;
997 l->silent_intv_cnt = 0;
998 l->rst_cnt = 0;
999 l->bc_peer_is_up = false;
1000 memset(&l->mon_state, 0, sizeof(l->mon_state));
1001 tipc_link_reset_stats(l);
1002}
1003
1004/**
1005 * tipc_link_xmit(): enqueue buffer list according to queue situation
1006 * @l: link to use
1007 * @list: chain of buffers containing message
1008 * @xmitq: returned list of packets to be sent by caller
1009 *
1010 * Consumes the buffer chain.
1011 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1012 * Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
1013 */
1014int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1015 struct sk_buff_head *xmitq)
1016{
1017 struct sk_buff_head *backlogq = &l->backlogq;
1018 struct sk_buff_head *transmq = &l->transmq;
1019 struct sk_buff *skb, *_skb;
1020 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1021 u16 ack = l->rcv_nxt - 1;
1022 u16 seqno = l->snd_nxt;
1023 int pkt_cnt = skb_queue_len(list);
1024 unsigned int mss = tipc_link_mss(l);
1025 unsigned int cwin = l->window;
1026 unsigned int mtu = l->mtu;
1027 struct tipc_msg *hdr;
1028 bool new_bundle;
1029 int rc = 0;
1030 int imp;
1031
1032 if (pkt_cnt <= 0)
1033 return 0;
1034
1035 hdr = buf_msg(skb_peek(list));
1036 if (unlikely(msg_size(hdr) > mtu)) {
1037 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1038 skb_queue_len(list), msg_user(hdr),
1039 msg_type(hdr), msg_size(hdr), mtu);
1040 __skb_queue_purge(list);
1041 return -EMSGSIZE;
1042 }
1043
1044 imp = msg_importance(hdr);
1045 /* Allow oversubscription of one data msg per source at congestion */
1046 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1047 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1048 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1049 return -ENOBUFS;
1050 }
1051 rc = link_schedule_user(l, hdr);
1052 }
1053
1054 if (pkt_cnt > 1) {
1055 l->stats.sent_fragmented++;
1056 l->stats.sent_fragments += pkt_cnt;
1057 }
1058
1059 /* Prepare each packet for sending, and add to relevant queue: */
1060 while ((skb = __skb_dequeue(list))) {
1061 if (likely(skb_queue_len(transmq) < cwin)) {
1062 hdr = buf_msg(skb);
1063 msg_set_seqno(hdr, seqno);
1064 msg_set_ack(hdr, ack);
1065 msg_set_bcast_ack(hdr, bc_ack);
1066 _skb = skb_clone(skb, GFP_ATOMIC);
1067 if (!_skb) {
1068 kfree_skb(skb);
1069 __skb_queue_purge(list);
1070 return -ENOBUFS;
1071 }
1072 __skb_queue_tail(transmq, skb);
1073 tipc_link_set_skb_retransmit_time(skb, l);
1074 __skb_queue_tail(xmitq, _skb);
1075 TIPC_SKB_CB(skb)->ackers = l->ackers;
1076 l->rcv_unacked = 0;
1077 l->stats.sent_pkts++;
1078 seqno++;
1079 continue;
1080 }
1081 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1082 mss, l->addr, &new_bundle)) {
1083 if (skb) {
1084 /* Keep a ref. to the skb for next try */
1085 l->backlog[imp].target_bskb = skb;
1086 l->backlog[imp].len++;
1087 __skb_queue_tail(backlogq, skb);
1088 } else {
1089 if (new_bundle) {
1090 l->stats.sent_bundles++;
1091 l->stats.sent_bundled++;
1092 }
1093 l->stats.sent_bundled++;
1094 }
1095 continue;
1096 }
1097 l->backlog[imp].target_bskb = NULL;
1098 l->backlog[imp].len += (1 + skb_queue_len(list));
1099 __skb_queue_tail(backlogq, skb);
1100 skb_queue_splice_tail_init(list, backlogq);
1101 }
1102 l->snd_nxt = seqno;
1103 return rc;
1104}
1105
1106static void tipc_link_update_cwin(struct tipc_link *l, int released,
1107 bool retransmitted)
1108{
1109 int bklog_len = skb_queue_len(&l->backlogq);
1110 struct sk_buff_head *txq = &l->transmq;
1111 int txq_len = skb_queue_len(txq);
1112 u16 cwin = l->window;
1113
1114 /* Enter fast recovery */
1115 if (unlikely(retransmitted)) {
1116 l->ssthresh = max_t(u16, l->window / 2, 300);
1117 l->window = min_t(u16, l->ssthresh, l->window);
1118 return;
1119 }
1120 /* Enter slow start */
1121 if (unlikely(!released)) {
1122 l->ssthresh = max_t(u16, l->window / 2, 300);
1123 l->window = l->min_win;
1124 return;
1125 }
1126 /* Don't increase window if no pressure on the transmit queue */
1127 if (txq_len + bklog_len < cwin)
1128 return;
1129
1130 /* Don't increase window if there are holes the transmit queue */
1131 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1132 return;
1133
1134 l->cong_acks += released;
1135
1136 /* Slow start */
1137 if (cwin <= l->ssthresh) {
1138 l->window = min_t(u16, cwin + released, l->max_win);
1139 return;
1140 }
1141 /* Congestion avoidance */
1142 if (l->cong_acks < cwin)
1143 return;
1144 l->window = min_t(u16, ++cwin, l->max_win);
1145 l->cong_acks = 0;
1146}
1147
1148static void tipc_link_advance_backlog(struct tipc_link *l,
1149 struct sk_buff_head *xmitq)
1150{
1151 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1152 struct sk_buff_head *txq = &l->transmq;
1153 struct sk_buff *skb, *_skb;
1154 u16 ack = l->rcv_nxt - 1;
1155 u16 seqno = l->snd_nxt;
1156 struct tipc_msg *hdr;
1157 u16 cwin = l->window;
1158 u32 imp;
1159
1160 while (skb_queue_len(txq) < cwin) {
1161 skb = skb_peek(&l->backlogq);
1162 if (!skb)
1163 break;
1164 _skb = skb_clone(skb, GFP_ATOMIC);
1165 if (!_skb)
1166 break;
1167 __skb_dequeue(&l->backlogq);
1168 hdr = buf_msg(skb);
1169 imp = msg_importance(hdr);
1170 l->backlog[imp].len--;
1171 if (unlikely(skb == l->backlog[imp].target_bskb))
1172 l->backlog[imp].target_bskb = NULL;
1173 __skb_queue_tail(&l->transmq, skb);
1174 tipc_link_set_skb_retransmit_time(skb, l);
1175
1176 __skb_queue_tail(xmitq, _skb);
1177 TIPC_SKB_CB(skb)->ackers = l->ackers;
1178 msg_set_seqno(hdr, seqno);
1179 msg_set_ack(hdr, ack);
1180 msg_set_bcast_ack(hdr, bc_ack);
1181 l->rcv_unacked = 0;
1182 l->stats.sent_pkts++;
1183 seqno++;
1184 }
1185 l->snd_nxt = seqno;
1186}
1187
1188/**
1189 * link_retransmit_failure() - Detect repeated retransmit failures
1190 * @l: tipc link sender
1191 * @r: tipc link receiver (= l in case of unicast)
1192 * @rc: returned code
1193 *
1194 * Return: true if the repeated retransmit failures happens, otherwise
1195 * false
1196 */
1197static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1198 int *rc)
1199{
1200 struct sk_buff *skb = skb_peek(&l->transmq);
1201 struct tipc_msg *hdr;
1202
1203 if (!skb)
1204 return false;
1205
1206 if (!TIPC_SKB_CB(skb)->retr_cnt)
1207 return false;
1208
1209 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1210 msecs_to_jiffies(r->tolerance * 10)))
1211 return false;
1212
1213 hdr = buf_msg(skb);
1214 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1215 return false;
1216
1217 pr_warn("Retransmission failure on link <%s>\n", l->name);
1218 link_print(l, "State of link ");
1219 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1220 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1221 pr_info("sqno %u, prev: %x, dest: %x\n",
1222 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1223 pr_info("retr_stamp %d, retr_cnt %d\n",
1224 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1225 TIPC_SKB_CB(skb)->retr_cnt);
1226
1227 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1228 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1229 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1230
1231 if (link_is_bc_sndlink(l)) {
1232 r->state = LINK_RESET;
1233 *rc |= TIPC_LINK_DOWN_EVT;
1234 } else {
1235 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1236 }
1237
1238 return true;
1239}
1240
1241/* tipc_data_input - deliver data and name distr msgs to upper layer
1242 *
1243 * Consumes buffer if message is of right type
1244 * Node lock must be held
1245 */
1246static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1247 struct sk_buff_head *inputq)
1248{
1249 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1250 struct tipc_msg *hdr = buf_msg(skb);
1251
1252 switch (msg_user(hdr)) {
1253 case TIPC_LOW_IMPORTANCE:
1254 case TIPC_MEDIUM_IMPORTANCE:
1255 case TIPC_HIGH_IMPORTANCE:
1256 case TIPC_CRITICAL_IMPORTANCE:
1257 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1258 skb_queue_tail(mc_inputq, skb);
1259 return true;
1260 }
1261 fallthrough;
1262 case CONN_MANAGER:
1263 skb_queue_tail(inputq, skb);
1264 return true;
1265 case GROUP_PROTOCOL:
1266 skb_queue_tail(mc_inputq, skb);
1267 return true;
1268 case NAME_DISTRIBUTOR:
1269 l->bc_rcvlink->state = LINK_ESTABLISHED;
1270 skb_queue_tail(l->namedq, skb);
1271 return true;
1272 case MSG_BUNDLER:
1273 case TUNNEL_PROTOCOL:
1274 case MSG_FRAGMENTER:
1275 case BCAST_PROTOCOL:
1276 return false;
1277#ifdef CONFIG_TIPC_CRYPTO
1278 case MSG_CRYPTO:
1279 if (sysctl_tipc_key_exchange_enabled &&
1280 TIPC_SKB_CB(skb)->decrypted) {
1281 tipc_crypto_msg_rcv(l->net, skb);
1282 return true;
1283 }
1284 fallthrough;
1285#endif
1286 default:
1287 pr_warn("Dropping received illegal msg type\n");
1288 kfree_skb(skb);
1289 return true;
1290 }
1291}
1292
1293/* tipc_link_input - process packet that has passed link protocol check
1294 *
1295 * Consumes buffer
1296 */
1297static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1298 struct sk_buff_head *inputq,
1299 struct sk_buff **reasm_skb)
1300{
1301 struct tipc_msg *hdr = buf_msg(skb);
1302 struct sk_buff *iskb;
1303 struct sk_buff_head tmpq;
1304 int usr = msg_user(hdr);
1305 int pos = 0;
1306
1307 if (usr == MSG_BUNDLER) {
1308 skb_queue_head_init(&tmpq);
1309 l->stats.recv_bundles++;
1310 l->stats.recv_bundled += msg_msgcnt(hdr);
1311 while (tipc_msg_extract(skb, &iskb, &pos))
1312 tipc_data_input(l, iskb, &tmpq);
1313 tipc_skb_queue_splice_tail(&tmpq, inputq);
1314 return 0;
1315 } else if (usr == MSG_FRAGMENTER) {
1316 l->stats.recv_fragments++;
1317 if (tipc_buf_append(reasm_skb, &skb)) {
1318 l->stats.recv_fragmented++;
1319 tipc_data_input(l, skb, inputq);
1320 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1321 pr_warn_ratelimited("Unable to build fragment list\n");
1322 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1323 }
1324 return 0;
1325 } else if (usr == BCAST_PROTOCOL) {
1326 tipc_bcast_lock(l->net);
1327 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1328 tipc_bcast_unlock(l->net);
1329 }
1330
1331 kfree_skb(skb);
1332 return 0;
1333}
1334
1335/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1336 * inner message along with the ones in the old link's
1337 * deferdq
1338 * @l: tunnel link
1339 * @skb: TUNNEL_PROTOCOL message
1340 * @inputq: queue to put messages ready for delivery
1341 */
1342static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1343 struct sk_buff_head *inputq)
1344{
1345 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1346 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1347 struct sk_buff_head *fdefq = &l->failover_deferdq;
1348 struct tipc_msg *hdr = buf_msg(skb);
1349 struct sk_buff *iskb;
1350 int ipos = 0;
1351 int rc = 0;
1352 u16 seqno;
1353
1354 if (msg_type(hdr) == SYNCH_MSG) {
1355 kfree_skb(skb);
1356 return 0;
1357 }
1358
1359 /* Not a fragment? */
1360 if (likely(!msg_nof_fragms(hdr))) {
1361 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1362 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1363 skb_queue_len(fdefq));
1364 return 0;
1365 }
1366 kfree_skb(skb);
1367 } else {
1368 /* Set fragment type for buf_append */
1369 if (msg_fragm_no(hdr) == 1)
1370 msg_set_type(hdr, FIRST_FRAGMENT);
1371 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1372 msg_set_type(hdr, FRAGMENT);
1373 else
1374 msg_set_type(hdr, LAST_FRAGMENT);
1375
1376 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1377 /* Successful but non-complete reassembly? */
1378 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1379 return 0;
1380 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1381 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1382 }
1383 iskb = skb;
1384 }
1385
1386 do {
1387 seqno = buf_seqno(iskb);
1388 if (unlikely(less(seqno, l->drop_point))) {
1389 kfree_skb(iskb);
1390 continue;
1391 }
1392 if (unlikely(seqno != l->drop_point)) {
1393 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1394 continue;
1395 }
1396
1397 l->drop_point++;
1398 if (!tipc_data_input(l, iskb, inputq))
1399 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1400 if (unlikely(rc))
1401 break;
1402 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1403
1404 return rc;
1405}
1406
1407/**
1408 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1409 * @ga: returned pointer to the Gap ACK blocks if any
1410 * @l: the tipc link
1411 * @hdr: the PROTOCOL/STATE_MSG header
1412 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1413 *
1414 * Return: the total Gap ACK blocks size
1415 */
1416u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1417 struct tipc_msg *hdr, bool uc)
1418{
1419 struct tipc_gap_ack_blks *p;
1420 u16 sz = 0;
1421
1422 /* Does peer support the Gap ACK blocks feature? */
1423 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1424 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1425 sz = ntohs(p->len);
1426 /* Sanity check */
1427 if (sz == struct_size(p, gacks, size_add(p->ugack_cnt, p->bgack_cnt))) {
1428 /* Good, check if the desired type exists */
1429 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1430 goto ok;
1431 /* Backward compatible: peer might not support bc, but uc? */
1432 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1433 if (p->ugack_cnt) {
1434 p->bgack_cnt = 0;
1435 goto ok;
1436 }
1437 }
1438 }
1439 /* Other cases: ignore! */
1440 p = NULL;
1441
1442ok:
1443 *ga = p;
1444 return sz;
1445}
1446
1447static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1448 struct tipc_link *l, u8 start_index)
1449{
1450 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1451 struct sk_buff *skb = skb_peek(&l->deferdq);
1452 u16 expect, seqno = 0;
1453 u8 n = 0;
1454
1455 if (!skb)
1456 return 0;
1457
1458 expect = buf_seqno(skb);
1459 skb_queue_walk(&l->deferdq, skb) {
1460 seqno = buf_seqno(skb);
1461 if (unlikely(more(seqno, expect))) {
1462 gacks[n].ack = htons(expect - 1);
1463 gacks[n].gap = htons(seqno - expect);
1464 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1465 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1466 l->name, n,
1467 skb_queue_len(&l->deferdq));
1468 return n;
1469 }
1470 } else if (unlikely(less(seqno, expect))) {
1471 pr_warn("Unexpected skb in deferdq!\n");
1472 continue;
1473 }
1474 expect = seqno + 1;
1475 }
1476
1477 /* last block */
1478 gacks[n].ack = htons(seqno);
1479 gacks[n].gap = 0;
1480 n++;
1481 return n;
1482}
1483
1484/* tipc_build_gap_ack_blks - build Gap ACK blocks
1485 * @l: tipc unicast link
1486 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1487 *
1488 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1489 * links of a certain peer, the buffer after built has the network data format
1490 * as found at the struct tipc_gap_ack_blks definition.
1491 *
1492 * returns the actual allocated memory size
1493 */
1494static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1495{
1496 struct tipc_link *bcl = l->bc_rcvlink;
1497 struct tipc_gap_ack_blks *ga;
1498 u16 len;
1499
1500 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1501
1502 /* Start with broadcast link first */
1503 tipc_bcast_lock(bcl->net);
1504 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1505 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1506 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1507 tipc_bcast_unlock(bcl->net);
1508
1509 /* Now for unicast link, but an explicit NACK only (???) */
1510 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1511 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1512
1513 /* Total len */
1514 len = struct_size(ga, gacks, size_add(ga->bgack_cnt, ga->ugack_cnt));
1515 ga->len = htons(len);
1516 return len;
1517}
1518
1519/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1520 * acked packets, also doing retransmissions if
1521 * gaps found
1522 * @l: tipc link with transmq queue to be advanced
1523 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1524 * @acked: seqno of last packet acked by peer without any gaps before
1525 * @gap: # of gap packets
1526 * @ga: buffer pointer to Gap ACK blocks from peer
1527 * @xmitq: queue for accumulating the retransmitted packets if any
1528 * @retransmitted: returned boolean value if a retransmission is really issued
1529 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1530 * happens (- unlikely case)
1531 *
1532 * Return: the number of packets released from the link transmq
1533 */
1534static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1535 u16 acked, u16 gap,
1536 struct tipc_gap_ack_blks *ga,
1537 struct sk_buff_head *xmitq,
1538 bool *retransmitted, int *rc)
1539{
1540 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1541 struct tipc_gap_ack *gacks = NULL;
1542 struct sk_buff *skb, *_skb, *tmp;
1543 struct tipc_msg *hdr;
1544 u32 qlen = skb_queue_len(&l->transmq);
1545 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1546 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1547 u16 ack = l->rcv_nxt - 1;
1548 u16 seqno, n = 0;
1549 u16 end = r->acked, start = end, offset = r->last_gap;
1550 u16 si = (last_ga) ? last_ga->start_index : 0;
1551 bool is_uc = !link_is_bc_sndlink(l);
1552 bool bc_has_acked = false;
1553
1554 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1555
1556 /* Determine Gap ACK blocks if any for the particular link */
1557 if (ga && is_uc) {
1558 /* Get the Gap ACKs, uc part */
1559 gack_cnt = ga->ugack_cnt;
1560 gacks = &ga->gacks[ga->bgack_cnt];
1561 } else if (ga) {
1562 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1563 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1564 GFP_ATOMIC);
1565 if (likely(this_ga)) {
1566 this_ga->start_index = 0;
1567 /* Start with the bc Gap ACKs */
1568 gack_cnt = this_ga->bgack_cnt;
1569 gacks = &this_ga->gacks[0];
1570 } else {
1571 /* Hmm, we can get in trouble..., simply ignore it */
1572 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1573 }
1574 }
1575
1576 /* Advance the link transmq */
1577 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1578 seqno = buf_seqno(skb);
1579
1580next_gap_ack:
1581 if (less_eq(seqno, nacked)) {
1582 if (is_uc)
1583 goto release;
1584 /* Skip packets peer has already acked */
1585 if (!more(seqno, r->acked))
1586 continue;
1587 /* Get the next of last Gap ACK blocks */
1588 while (more(seqno, end)) {
1589 if (!last_ga || si >= last_ga->bgack_cnt)
1590 break;
1591 start = end + offset + 1;
1592 end = ntohs(last_ga->gacks[si].ack);
1593 offset = ntohs(last_ga->gacks[si].gap);
1594 si++;
1595 WARN_ONCE(more(start, end) ||
1596 (!offset &&
1597 si < last_ga->bgack_cnt) ||
1598 si > MAX_GAP_ACK_BLKS,
1599 "Corrupted Gap ACK: %d %d %d %d %d\n",
1600 start, end, offset, si,
1601 last_ga->bgack_cnt);
1602 }
1603 /* Check against the last Gap ACK block */
1604 if (tipc_in_range(seqno, start, end))
1605 continue;
1606 /* Update/release the packet peer is acking */
1607 bc_has_acked = true;
1608 if (--TIPC_SKB_CB(skb)->ackers)
1609 continue;
1610release:
1611 /* release skb */
1612 __skb_unlink(skb, &l->transmq);
1613 kfree_skb(skb);
1614 } else if (less_eq(seqno, nacked + ngap)) {
1615 /* First gap: check if repeated retrans failures? */
1616 if (unlikely(seqno == acked + 1 &&
1617 link_retransmit_failure(l, r, rc))) {
1618 /* Ignore this bc Gap ACKs if any */
1619 kfree(this_ga);
1620 this_ga = NULL;
1621 break;
1622 }
1623 /* retransmit skb if unrestricted*/
1624 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1625 continue;
1626 tipc_link_set_skb_retransmit_time(skb, l);
1627 _skb = pskb_copy(skb, GFP_ATOMIC);
1628 if (!_skb)
1629 continue;
1630 hdr = buf_msg(_skb);
1631 msg_set_ack(hdr, ack);
1632 msg_set_bcast_ack(hdr, bc_ack);
1633 _skb->priority = TC_PRIO_CONTROL;
1634 __skb_queue_tail(xmitq, _skb);
1635 l->stats.retransmitted++;
1636 if (!is_uc)
1637 r->stats.retransmitted++;
1638 *retransmitted = true;
1639 /* Increase actual retrans counter & mark first time */
1640 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1641 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1642 } else {
1643 /* retry with Gap ACK blocks if any */
1644 if (n >= gack_cnt)
1645 break;
1646 nacked = ntohs(gacks[n].ack);
1647 ngap = ntohs(gacks[n].gap);
1648 n++;
1649 goto next_gap_ack;
1650 }
1651 }
1652
1653 /* Renew last Gap ACK blocks for bc if needed */
1654 if (bc_has_acked) {
1655 if (this_ga) {
1656 kfree(last_ga);
1657 r->last_ga = this_ga;
1658 r->last_gap = gap;
1659 } else if (last_ga) {
1660 if (less(acked, start)) {
1661 si--;
1662 offset = start - acked - 1;
1663 } else if (less(acked, end)) {
1664 acked = end;
1665 }
1666 if (si < last_ga->bgack_cnt) {
1667 last_ga->start_index = si;
1668 r->last_gap = offset;
1669 } else {
1670 kfree(last_ga);
1671 r->last_ga = NULL;
1672 r->last_gap = 0;
1673 }
1674 } else {
1675 r->last_gap = 0;
1676 }
1677 r->acked = acked;
1678 } else {
1679 kfree(this_ga);
1680 }
1681
1682 return qlen - skb_queue_len(&l->transmq);
1683}
1684
1685/* tipc_link_build_state_msg: prepare link state message for transmission
1686 *
1687 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1688 * risk of ack storms towards the sender
1689 */
1690int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1691{
1692 if (!l)
1693 return 0;
1694
1695 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1696 if (link_is_bc_rcvlink(l)) {
1697 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1698 return 0;
1699 l->rcv_unacked = 0;
1700
1701 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1702 l->snd_nxt = l->rcv_nxt;
1703 return TIPC_LINK_SND_STATE;
1704 }
1705 /* Unicast ACK */
1706 l->rcv_unacked = 0;
1707 l->stats.sent_acks++;
1708 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1709 return 0;
1710}
1711
1712/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1713 */
1714void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1715{
1716 int mtyp = RESET_MSG;
1717 struct sk_buff *skb;
1718
1719 if (l->state == LINK_ESTABLISHING)
1720 mtyp = ACTIVATE_MSG;
1721
1722 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1723
1724 /* Inform peer that this endpoint is going down if applicable */
1725 skb = skb_peek_tail(xmitq);
1726 if (skb && (l->state == LINK_RESET))
1727 msg_set_peer_stopping(buf_msg(skb), 1);
1728}
1729
1730/* tipc_link_build_nack_msg: prepare link nack message for transmission
1731 * Note that sending of broadcast NACK is coordinated among nodes, to
1732 * reduce the risk of NACK storms towards the sender
1733 */
1734static int tipc_link_build_nack_msg(struct tipc_link *l,
1735 struct sk_buff_head *xmitq)
1736{
1737 u32 def_cnt = ++l->stats.deferred_recv;
1738 struct sk_buff_head *dfq = &l->deferdq;
1739 u32 defq_len = skb_queue_len(dfq);
1740 int match1, match2;
1741
1742 if (link_is_bc_rcvlink(l)) {
1743 match1 = def_cnt & 0xf;
1744 match2 = tipc_own_addr(l->net) & 0xf;
1745 if (match1 == match2)
1746 return TIPC_LINK_SND_STATE;
1747 return 0;
1748 }
1749
1750 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1751 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1752
1753 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1754 rcvgap, 0, 0, xmitq);
1755 }
1756 return 0;
1757}
1758
1759/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1760 * @l: the link that should handle the message
1761 * @skb: TIPC packet
1762 * @xmitq: queue to place packets to be sent after this call
1763 */
1764int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1765 struct sk_buff_head *xmitq)
1766{
1767 struct sk_buff_head *defq = &l->deferdq;
1768 struct tipc_msg *hdr = buf_msg(skb);
1769 u16 seqno, rcv_nxt, win_lim;
1770 int released = 0;
1771 int rc = 0;
1772
1773 /* Verify and update link state */
1774 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1775 return tipc_link_proto_rcv(l, skb, xmitq);
1776
1777 /* Don't send probe at next timeout expiration */
1778 l->silent_intv_cnt = 0;
1779
1780 do {
1781 hdr = buf_msg(skb);
1782 seqno = msg_seqno(hdr);
1783 rcv_nxt = l->rcv_nxt;
1784 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1785
1786 if (unlikely(!tipc_link_is_up(l))) {
1787 if (l->state == LINK_ESTABLISHING)
1788 rc = TIPC_LINK_UP_EVT;
1789 kfree_skb(skb);
1790 break;
1791 }
1792
1793 /* Drop if outside receive window */
1794 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1795 l->stats.duplicates++;
1796 kfree_skb(skb);
1797 break;
1798 }
1799 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1800 NULL, NULL, NULL, NULL);
1801
1802 /* Defer delivery if sequence gap */
1803 if (unlikely(seqno != rcv_nxt)) {
1804 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1805 l->stats.duplicates++;
1806 rc |= tipc_link_build_nack_msg(l, xmitq);
1807 break;
1808 }
1809
1810 /* Deliver packet */
1811 l->rcv_nxt++;
1812 l->stats.recv_pkts++;
1813
1814 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1815 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1816 else if (!tipc_data_input(l, skb, l->inputq))
1817 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1818 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1819 rc |= tipc_link_build_state_msg(l, xmitq);
1820 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1821 break;
1822 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1823
1824 /* Forward queues and wake up waiting users */
1825 if (released) {
1826 tipc_link_update_cwin(l, released, 0);
1827 tipc_link_advance_backlog(l, xmitq);
1828 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1829 link_prepare_wakeup(l);
1830 }
1831 return rc;
1832}
1833
1834static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1835 bool probe_reply, u16 rcvgap,
1836 int tolerance, int priority,
1837 struct sk_buff_head *xmitq)
1838{
1839 struct tipc_mon_state *mstate = &l->mon_state;
1840 struct sk_buff_head *dfq = &l->deferdq;
1841 struct tipc_link *bcl = l->bc_rcvlink;
1842 struct tipc_msg *hdr;
1843 struct sk_buff *skb;
1844 bool node_up = tipc_link_is_up(bcl);
1845 u16 glen = 0, bc_rcvgap = 0;
1846 int dlen = 0;
1847 void *data;
1848
1849 /* Don't send protocol message during reset or link failover */
1850 if (tipc_link_is_blocked(l))
1851 return;
1852
1853 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1854 return;
1855
1856 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1857 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1858
1859 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1860 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1861 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1862 if (!skb)
1863 return;
1864
1865 hdr = buf_msg(skb);
1866 data = msg_data(hdr);
1867 msg_set_session(hdr, l->session);
1868 msg_set_bearer_id(hdr, l->bearer_id);
1869 msg_set_net_plane(hdr, l->net_plane);
1870 msg_set_next_sent(hdr, l->snd_nxt);
1871 msg_set_ack(hdr, l->rcv_nxt - 1);
1872 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1873 msg_set_bc_ack_invalid(hdr, !node_up);
1874 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1875 msg_set_link_tolerance(hdr, tolerance);
1876 msg_set_linkprio(hdr, priority);
1877 msg_set_redundant_link(hdr, node_up);
1878 msg_set_seq_gap(hdr, 0);
1879 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1880
1881 if (mtyp == STATE_MSG) {
1882 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1883 msg_set_seqno(hdr, l->snd_nxt_state++);
1884 msg_set_seq_gap(hdr, rcvgap);
1885 bc_rcvgap = link_bc_rcv_gap(bcl);
1886 msg_set_bc_gap(hdr, bc_rcvgap);
1887 msg_set_probe(hdr, probe);
1888 msg_set_is_keepalive(hdr, probe || probe_reply);
1889 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1890 glen = tipc_build_gap_ack_blks(l, hdr);
1891 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1892 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1893 skb_trim(skb, INT_H_SIZE + glen + dlen);
1894 l->stats.sent_states++;
1895 l->rcv_unacked = 0;
1896 } else {
1897 /* RESET_MSG or ACTIVATE_MSG */
1898 if (mtyp == ACTIVATE_MSG) {
1899 msg_set_dest_session_valid(hdr, 1);
1900 msg_set_dest_session(hdr, l->peer_session);
1901 }
1902 msg_set_max_pkt(hdr, l->advertised_mtu);
1903 strcpy(data, l->if_name);
1904 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1905 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1906 }
1907 if (probe)
1908 l->stats.sent_probes++;
1909 if (rcvgap)
1910 l->stats.sent_nacks++;
1911 if (bc_rcvgap)
1912 bcl->stats.sent_nacks++;
1913 skb->priority = TC_PRIO_CONTROL;
1914 __skb_queue_tail(xmitq, skb);
1915 trace_tipc_proto_build(skb, false, l->name);
1916}
1917
1918void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1919 struct sk_buff_head *xmitq)
1920{
1921 u32 onode = tipc_own_addr(l->net);
1922 struct tipc_msg *hdr, *ihdr;
1923 struct sk_buff_head tnlq;
1924 struct sk_buff *skb;
1925 u32 dnode = l->addr;
1926
1927 __skb_queue_head_init(&tnlq);
1928 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1929 INT_H_SIZE, BASIC_H_SIZE,
1930 dnode, onode, 0, 0, 0);
1931 if (!skb) {
1932 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1933 return;
1934 }
1935
1936 hdr = buf_msg(skb);
1937 msg_set_msgcnt(hdr, 1);
1938 msg_set_bearer_id(hdr, l->peer_bearer_id);
1939
1940 ihdr = (struct tipc_msg *)msg_data(hdr);
1941 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1942 BASIC_H_SIZE, dnode);
1943 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1944 __skb_queue_tail(&tnlq, skb);
1945 tipc_link_xmit(l, &tnlq, xmitq);
1946}
1947
1948/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1949 * with contents of the link's transmit and backlog queues.
1950 */
1951void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1952 int mtyp, struct sk_buff_head *xmitq)
1953{
1954 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1955 struct sk_buff *skb, *tnlskb;
1956 struct tipc_msg *hdr, tnlhdr;
1957 struct sk_buff_head *queue = &l->transmq;
1958 struct sk_buff_head tmpxq, tnlq, frags;
1959 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1960 bool pktcnt_need_update = false;
1961 u16 syncpt;
1962 int rc;
1963
1964 if (!tnl)
1965 return;
1966
1967 __skb_queue_head_init(&tnlq);
1968 /* Link Synching:
1969 * From now on, send only one single ("dummy") SYNCH message
1970 * to peer. The SYNCH message does not contain any data, just
1971 * a header conveying the synch point to the peer.
1972 */
1973 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1974 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1975 INT_H_SIZE, 0, l->addr,
1976 tipc_own_addr(l->net),
1977 0, 0, 0);
1978 if (!tnlskb) {
1979 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1980 link_co_err);
1981 return;
1982 }
1983
1984 hdr = buf_msg(tnlskb);
1985 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1986 msg_set_syncpt(hdr, syncpt);
1987 msg_set_bearer_id(hdr, l->peer_bearer_id);
1988 __skb_queue_tail(&tnlq, tnlskb);
1989 tipc_link_xmit(tnl, &tnlq, xmitq);
1990 return;
1991 }
1992
1993 __skb_queue_head_init(&tmpxq);
1994 __skb_queue_head_init(&frags);
1995 /* At least one packet required for safe algorithm => add dummy */
1996 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1997 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1998 0, 0, TIPC_ERR_NO_PORT);
1999 if (!skb) {
2000 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2001 return;
2002 }
2003 __skb_queue_tail(&tnlq, skb);
2004 tipc_link_xmit(l, &tnlq, &tmpxq);
2005 __skb_queue_purge(&tmpxq);
2006
2007 /* Initialize reusable tunnel packet header */
2008 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2009 mtyp, INT_H_SIZE, l->addr);
2010 if (mtyp == SYNCH_MSG)
2011 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2012 else
2013 pktcnt = skb_queue_len(&l->transmq);
2014 pktcnt += skb_queue_len(&l->backlogq);
2015 msg_set_msgcnt(&tnlhdr, pktcnt);
2016 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2017tnl:
2018 /* Wrap each packet into a tunnel packet */
2019 skb_queue_walk(queue, skb) {
2020 hdr = buf_msg(skb);
2021 if (queue == &l->backlogq)
2022 msg_set_seqno(hdr, seqno++);
2023 pktlen = msg_size(hdr);
2024
2025 /* Tunnel link MTU is not large enough? This could be
2026 * due to:
2027 * 1) Link MTU has just changed or set differently;
2028 * 2) Or FAILOVER on the top of a SYNCH message
2029 *
2030 * The 2nd case should not happen if peer supports
2031 * TIPC_TUNNEL_ENHANCED
2032 */
2033 if (pktlen > tnl->mtu - INT_H_SIZE) {
2034 if (mtyp == FAILOVER_MSG &&
2035 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2036 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2037 &frags);
2038 if (rc) {
2039 pr_warn("%sunable to frag msg: rc %d\n",
2040 link_co_err, rc);
2041 return;
2042 }
2043 pktcnt += skb_queue_len(&frags) - 1;
2044 pktcnt_need_update = true;
2045 skb_queue_splice_tail_init(&frags, &tnlq);
2046 continue;
2047 }
2048 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2049 * => Just warn it and return!
2050 */
2051 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2052 link_co_err, msg_user(hdr),
2053 msg_type(hdr), msg_size(hdr));
2054 return;
2055 }
2056
2057 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2058 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2059 if (!tnlskb) {
2060 pr_warn("%sunable to send packet\n", link_co_err);
2061 return;
2062 }
2063 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2064 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2065 __skb_queue_tail(&tnlq, tnlskb);
2066 }
2067 if (queue != &l->backlogq) {
2068 queue = &l->backlogq;
2069 goto tnl;
2070 }
2071
2072 if (pktcnt_need_update)
2073 skb_queue_walk(&tnlq, skb) {
2074 hdr = buf_msg(skb);
2075 msg_set_msgcnt(hdr, pktcnt);
2076 }
2077
2078 tipc_link_xmit(tnl, &tnlq, xmitq);
2079
2080 if (mtyp == FAILOVER_MSG) {
2081 tnl->drop_point = l->rcv_nxt;
2082 tnl->failover_reasm_skb = l->reasm_buf;
2083 l->reasm_buf = NULL;
2084
2085 /* Failover the link's deferdq */
2086 if (unlikely(!skb_queue_empty(fdefq))) {
2087 pr_warn("Link failover deferdq not empty: %d!\n",
2088 skb_queue_len(fdefq));
2089 __skb_queue_purge(fdefq);
2090 }
2091 skb_queue_splice_init(&l->deferdq, fdefq);
2092 }
2093}
2094
2095/**
2096 * tipc_link_failover_prepare() - prepare tnl for link failover
2097 *
2098 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2099 * see the tipc_node_link_failover() for details
2100 *
2101 * @l: failover link
2102 * @tnl: tunnel link
2103 * @xmitq: queue for messages to be xmited
2104 */
2105void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2106 struct sk_buff_head *xmitq)
2107{
2108 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2109
2110 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2111
2112 /* This failover link endpoint was never established before,
2113 * so it has not received anything from peer.
2114 * Otherwise, it must be a normal failover situation or the
2115 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2116 * would have to start over from scratch instead.
2117 */
2118 tnl->drop_point = 1;
2119 tnl->failover_reasm_skb = NULL;
2120
2121 /* Initiate the link's failover deferdq */
2122 if (unlikely(!skb_queue_empty(fdefq))) {
2123 pr_warn("Link failover deferdq not empty: %d!\n",
2124 skb_queue_len(fdefq));
2125 __skb_queue_purge(fdefq);
2126 }
2127}
2128
2129/* tipc_link_validate_msg(): validate message against current link state
2130 * Returns true if message should be accepted, otherwise false
2131 */
2132bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2133{
2134 u16 curr_session = l->peer_session;
2135 u16 session = msg_session(hdr);
2136 int mtyp = msg_type(hdr);
2137
2138 if (msg_user(hdr) != LINK_PROTOCOL)
2139 return true;
2140
2141 switch (mtyp) {
2142 case RESET_MSG:
2143 if (!l->in_session)
2144 return true;
2145 /* Accept only RESET with new session number */
2146 return more(session, curr_session);
2147 case ACTIVATE_MSG:
2148 if (!l->in_session)
2149 return true;
2150 /* Accept only ACTIVATE with new or current session number */
2151 return !less(session, curr_session);
2152 case STATE_MSG:
2153 /* Accept only STATE with current session number */
2154 if (!l->in_session)
2155 return false;
2156 if (session != curr_session)
2157 return false;
2158 /* Extra sanity check */
2159 if (!tipc_link_is_up(l) && msg_ack(hdr))
2160 return false;
2161 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2162 return true;
2163 /* Accept only STATE with new sequence number */
2164 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2165 default:
2166 return false;
2167 }
2168}
2169
2170/* tipc_link_proto_rcv(): receive link level protocol message :
2171 * Note that network plane id propagates through the network, and may
2172 * change at any time. The node with lowest numerical id determines
2173 * network plane
2174 */
2175static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2176 struct sk_buff_head *xmitq)
2177{
2178 struct tipc_msg *hdr = buf_msg(skb);
2179 struct tipc_gap_ack_blks *ga = NULL;
2180 bool reply = msg_probe(hdr), retransmitted = false;
2181 u32 dlen = msg_data_sz(hdr), glen = 0, msg_max;
2182 u16 peers_snd_nxt = msg_next_sent(hdr);
2183 u16 peers_tol = msg_link_tolerance(hdr);
2184 u16 peers_prio = msg_linkprio(hdr);
2185 u16 gap = msg_seq_gap(hdr);
2186 u16 ack = msg_ack(hdr);
2187 u16 rcv_nxt = l->rcv_nxt;
2188 u16 rcvgap = 0;
2189 int mtyp = msg_type(hdr);
2190 int rc = 0, released;
2191 char *if_name;
2192 void *data;
2193
2194 trace_tipc_proto_rcv(skb, false, l->name);
2195
2196 if (dlen > U16_MAX)
2197 goto exit;
2198
2199 if (tipc_link_is_blocked(l) || !xmitq)
2200 goto exit;
2201
2202 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2203 l->net_plane = msg_net_plane(hdr);
2204
2205 if (skb_linearize(skb))
2206 goto exit;
2207
2208 hdr = buf_msg(skb);
2209 data = msg_data(hdr);
2210
2211 if (!tipc_link_validate_msg(l, hdr)) {
2212 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2213 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2214 goto exit;
2215 }
2216
2217 switch (mtyp) {
2218 case RESET_MSG:
2219 case ACTIVATE_MSG:
2220 msg_max = msg_max_pkt(hdr);
2221 if (msg_max < tipc_bearer_min_mtu(l->net, l->bearer_id))
2222 break;
2223 /* Complete own link name with peer's interface name */
2224 if_name = strrchr(l->name, ':') + 1;
2225 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2226 break;
2227 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2228 break;
2229 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2230
2231 /* Update own tolerance if peer indicates a non-zero value */
2232 if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2233 l->tolerance = peers_tol;
2234 l->bc_rcvlink->tolerance = peers_tol;
2235 }
2236 /* Update own priority if peer's priority is higher */
2237 if (tipc_in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2238 l->priority = peers_prio;
2239
2240 /* If peer is going down we want full re-establish cycle */
2241 if (msg_peer_stopping(hdr)) {
2242 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2243 break;
2244 }
2245
2246 /* If this endpoint was re-created while peer was ESTABLISHING
2247 * it doesn't know current session number. Force re-synch.
2248 */
2249 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2250 l->session != msg_dest_session(hdr)) {
2251 if (less(l->session, msg_dest_session(hdr)))
2252 l->session = msg_dest_session(hdr) + 1;
2253 break;
2254 }
2255
2256 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2257 if (mtyp == RESET_MSG || !tipc_link_is_up(l))
2258 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2259
2260 /* ACTIVATE_MSG takes up link if it was already locally reset */
2261 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2262 rc = TIPC_LINK_UP_EVT;
2263
2264 l->peer_session = msg_session(hdr);
2265 l->in_session = true;
2266 l->peer_bearer_id = msg_bearer_id(hdr);
2267 if (l->mtu > msg_max)
2268 l->mtu = msg_max;
2269 break;
2270
2271 case STATE_MSG:
2272 /* Validate Gap ACK blocks, drop if invalid */
2273 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2274 if (glen > dlen)
2275 break;
2276
2277 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2278
2279 /* Update own tolerance if peer indicates a non-zero value */
2280 if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2281 l->tolerance = peers_tol;
2282 l->bc_rcvlink->tolerance = peers_tol;
2283 }
2284 /* Update own prio if peer indicates a different value */
2285 if ((peers_prio != l->priority) &&
2286 tipc_in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2287 l->priority = peers_prio;
2288 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2289 }
2290
2291 l->silent_intv_cnt = 0;
2292 l->stats.recv_states++;
2293 if (msg_probe(hdr))
2294 l->stats.recv_probes++;
2295
2296 if (!tipc_link_is_up(l)) {
2297 if (l->state == LINK_ESTABLISHING)
2298 rc = TIPC_LINK_UP_EVT;
2299 break;
2300 }
2301
2302 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2303 &l->mon_state, l->bearer_id);
2304
2305 /* Send NACK if peer has sent pkts we haven't received yet */
2306 if ((reply || msg_is_keepalive(hdr)) &&
2307 more(peers_snd_nxt, rcv_nxt) &&
2308 !tipc_link_is_synching(l) &&
2309 skb_queue_empty(&l->deferdq))
2310 rcvgap = peers_snd_nxt - l->rcv_nxt;
2311 if (rcvgap || reply)
2312 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2313 rcvgap, 0, 0, xmitq);
2314
2315 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2316 &retransmitted, &rc);
2317 if (gap)
2318 l->stats.recv_nacks++;
2319 if (released || retransmitted)
2320 tipc_link_update_cwin(l, released, retransmitted);
2321 if (released)
2322 tipc_link_advance_backlog(l, xmitq);
2323 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2324 link_prepare_wakeup(l);
2325 }
2326exit:
2327 kfree_skb(skb);
2328 return rc;
2329}
2330
2331/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2332 */
2333static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2334 u16 peers_snd_nxt,
2335 struct sk_buff_head *xmitq)
2336{
2337 struct sk_buff *skb;
2338 struct tipc_msg *hdr;
2339 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2340 u16 ack = l->rcv_nxt - 1;
2341 u16 gap_to = peers_snd_nxt - 1;
2342
2343 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2344 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2345 if (!skb)
2346 return false;
2347 hdr = buf_msg(skb);
2348 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2349 msg_set_bcast_ack(hdr, ack);
2350 msg_set_bcgap_after(hdr, ack);
2351 if (dfrd_skb)
2352 gap_to = buf_seqno(dfrd_skb) - 1;
2353 msg_set_bcgap_to(hdr, gap_to);
2354 msg_set_non_seq(hdr, bcast);
2355 __skb_queue_tail(xmitq, skb);
2356 return true;
2357}
2358
2359/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2360 *
2361 * Give a newly added peer node the sequence number where it should
2362 * start receiving and acking broadcast packets.
2363 */
2364static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2365 struct sk_buff_head *xmitq)
2366{
2367 struct sk_buff_head list;
2368
2369 __skb_queue_head_init(&list);
2370 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2371 return;
2372 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2373 tipc_link_xmit(l, &list, xmitq);
2374}
2375
2376/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2377 */
2378void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2379{
2380 int mtyp = msg_type(hdr);
2381 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2382
2383 if (tipc_link_is_up(l))
2384 return;
2385
2386 if (msg_user(hdr) == BCAST_PROTOCOL) {
2387 l->rcv_nxt = peers_snd_nxt;
2388 l->state = LINK_ESTABLISHED;
2389 return;
2390 }
2391
2392 if (l->peer_caps & TIPC_BCAST_SYNCH)
2393 return;
2394
2395 if (msg_peer_node_is_up(hdr))
2396 return;
2397
2398 /* Compatibility: accept older, less safe initial synch data */
2399 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2400 l->rcv_nxt = peers_snd_nxt;
2401}
2402
2403/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2404 */
2405int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2406 struct sk_buff_head *xmitq)
2407{
2408 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2409 int rc = 0;
2410
2411 if (!tipc_link_is_up(l))
2412 return rc;
2413
2414 if (!msg_peer_node_is_up(hdr))
2415 return rc;
2416
2417 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2418 if (msg_ack(hdr))
2419 l->bc_peer_is_up = true;
2420
2421 if (!l->bc_peer_is_up)
2422 return rc;
2423
2424 /* Ignore if peers_snd_nxt goes beyond receive window */
2425 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2426 return rc;
2427
2428 l->snd_nxt = peers_snd_nxt;
2429 if (link_bc_rcv_gap(l))
2430 rc |= TIPC_LINK_SND_STATE;
2431
2432 /* Return now if sender supports nack via STATE messages */
2433 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2434 return rc;
2435
2436 /* Otherwise, be backwards compatible */
2437
2438 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2439 l->nack_state = BC_NACK_SND_CONDITIONAL;
2440 return 0;
2441 }
2442
2443 /* Don't NACK if one was recently sent or peeked */
2444 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2445 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2446 return 0;
2447 }
2448
2449 /* Conditionally delay NACK sending until next synch rcv */
2450 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2451 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2452 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2453 return 0;
2454 }
2455
2456 /* Send NACK now but suppress next one */
2457 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2458 l->nack_state = BC_NACK_SND_SUPPRESS;
2459 return 0;
2460}
2461
2462int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2463 struct tipc_gap_ack_blks *ga,
2464 struct sk_buff_head *xmitq,
2465 struct sk_buff_head *retrq)
2466{
2467 struct tipc_link *l = r->bc_sndlink;
2468 bool unused = false;
2469 int rc = 0;
2470
2471 if (!tipc_link_is_up(r) || !r->bc_peer_is_up)
2472 return 0;
2473
2474 if (gap) {
2475 l->stats.recv_nacks++;
2476 r->stats.recv_nacks++;
2477 }
2478
2479 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2480 return 0;
2481
2482 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2483 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2484
2485 tipc_link_advance_backlog(l, xmitq);
2486 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2487 link_prepare_wakeup(l);
2488
2489 return rc;
2490}
2491
2492/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2493 * This function is here for backwards compatibility, since
2494 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2495 */
2496int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2497 struct sk_buff_head *xmitq)
2498{
2499 struct tipc_msg *hdr = buf_msg(skb);
2500 u32 dnode = msg_destnode(hdr);
2501 int mtyp = msg_type(hdr);
2502 u16 acked = msg_bcast_ack(hdr);
2503 u16 from = acked + 1;
2504 u16 to = msg_bcgap_to(hdr);
2505 u16 peers_snd_nxt = to + 1;
2506 int rc = 0;
2507
2508 kfree_skb(skb);
2509
2510 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2511 return 0;
2512
2513 if (mtyp != STATE_MSG)
2514 return 0;
2515
2516 if (dnode == tipc_own_addr(l->net)) {
2517 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2518 xmitq);
2519 l->stats.recv_nacks++;
2520 return rc;
2521 }
2522
2523 /* Msg for other node => suppress own NACK at next sync if applicable */
2524 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2525 l->nack_state = BC_NACK_SND_SUPPRESS;
2526
2527 return 0;
2528}
2529
2530void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2531{
2532 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2533
2534 l->min_win = min_win;
2535 l->ssthresh = max_win;
2536 l->max_win = max_win;
2537 l->window = min_win;
2538 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2539 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2540 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2541 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2542 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2543}
2544
2545/**
2546 * tipc_link_reset_stats - reset link statistics
2547 * @l: pointer to link
2548 */
2549void tipc_link_reset_stats(struct tipc_link *l)
2550{
2551 memset(&l->stats, 0, sizeof(l->stats));
2552}
2553
2554static void link_print(struct tipc_link *l, const char *str)
2555{
2556 struct sk_buff *hskb = skb_peek(&l->transmq);
2557 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2558 u16 tail = l->snd_nxt - 1;
2559
2560 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2561 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2562 skb_queue_len(&l->transmq), head, tail,
2563 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2564}
2565
2566/* Parse and validate nested (link) properties valid for media, bearer and link
2567 */
2568int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2569{
2570 int err;
2571
2572 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2573 tipc_nl_prop_policy, NULL);
2574 if (err)
2575 return err;
2576
2577 if (props[TIPC_NLA_PROP_PRIO]) {
2578 u32 prio;
2579
2580 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2581 if (prio > TIPC_MAX_LINK_PRI)
2582 return -EINVAL;
2583 }
2584
2585 if (props[TIPC_NLA_PROP_TOL]) {
2586 u32 tol;
2587
2588 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2589 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2590 return -EINVAL;
2591 }
2592
2593 if (props[TIPC_NLA_PROP_WIN]) {
2594 u32 max_win;
2595
2596 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2597 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2598 return -EINVAL;
2599 }
2600
2601 return 0;
2602}
2603
2604static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2605{
2606 int i;
2607 struct nlattr *stats;
2608
2609 struct nla_map {
2610 u32 key;
2611 u32 val;
2612 };
2613
2614 struct nla_map map[] = {
2615 {TIPC_NLA_STATS_RX_INFO, 0},
2616 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2617 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2618 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2619 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2620 {TIPC_NLA_STATS_TX_INFO, 0},
2621 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2622 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2623 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2624 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2625 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2626 s->msg_length_counts : 1},
2627 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2628 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2629 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2630 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2631 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2632 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2633 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2634 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2635 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2636 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2637 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2638 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2639 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2640 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2641 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2642 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2643 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2644 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2645 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2646 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2647 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2648 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2649 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2650 };
2651
2652 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2653 if (!stats)
2654 return -EMSGSIZE;
2655
2656 for (i = 0; i < ARRAY_SIZE(map); i++)
2657 if (nla_put_u32(skb, map[i].key, map[i].val))
2658 goto msg_full;
2659
2660 nla_nest_end(skb, stats);
2661
2662 return 0;
2663msg_full:
2664 nla_nest_cancel(skb, stats);
2665
2666 return -EMSGSIZE;
2667}
2668
2669/* Caller should hold appropriate locks to protect the link */
2670int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2671 struct tipc_link *link, int nlflags)
2672{
2673 u32 self = tipc_own_addr(net);
2674 struct nlattr *attrs;
2675 struct nlattr *prop;
2676 void *hdr;
2677 int err;
2678
2679 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2680 nlflags, TIPC_NL_LINK_GET);
2681 if (!hdr)
2682 return -EMSGSIZE;
2683
2684 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2685 if (!attrs)
2686 goto msg_full;
2687
2688 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2689 goto attr_msg_full;
2690 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2691 goto attr_msg_full;
2692 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2693 goto attr_msg_full;
2694 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2695 goto attr_msg_full;
2696 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2697 goto attr_msg_full;
2698
2699 if (tipc_link_is_up(link))
2700 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2701 goto attr_msg_full;
2702 if (link->active)
2703 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2704 goto attr_msg_full;
2705
2706 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2707 if (!prop)
2708 goto attr_msg_full;
2709 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2710 goto prop_msg_full;
2711 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2712 goto prop_msg_full;
2713 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2714 link->window))
2715 goto prop_msg_full;
2716 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2717 goto prop_msg_full;
2718 nla_nest_end(msg->skb, prop);
2719
2720 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2721 if (err)
2722 goto attr_msg_full;
2723
2724 nla_nest_end(msg->skb, attrs);
2725 genlmsg_end(msg->skb, hdr);
2726
2727 return 0;
2728
2729prop_msg_full:
2730 nla_nest_cancel(msg->skb, prop);
2731attr_msg_full:
2732 nla_nest_cancel(msg->skb, attrs);
2733msg_full:
2734 genlmsg_cancel(msg->skb, hdr);
2735
2736 return -EMSGSIZE;
2737}
2738
2739static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2740 struct tipc_stats *stats)
2741{
2742 int i;
2743 struct nlattr *nest;
2744
2745 struct nla_map {
2746 __u32 key;
2747 __u32 val;
2748 };
2749
2750 struct nla_map map[] = {
2751 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2752 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2753 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2754 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2755 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2756 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2757 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2758 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2759 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2760 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2761 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2762 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2763 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2764 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2765 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2766 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2767 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2768 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2769 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2770 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2771 };
2772
2773 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2774 if (!nest)
2775 return -EMSGSIZE;
2776
2777 for (i = 0; i < ARRAY_SIZE(map); i++)
2778 if (nla_put_u32(skb, map[i].key, map[i].val))
2779 goto msg_full;
2780
2781 nla_nest_end(skb, nest);
2782
2783 return 0;
2784msg_full:
2785 nla_nest_cancel(skb, nest);
2786
2787 return -EMSGSIZE;
2788}
2789
2790int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2791 struct tipc_link *bcl)
2792{
2793 int err;
2794 void *hdr;
2795 struct nlattr *attrs;
2796 struct nlattr *prop;
2797 u32 bc_mode = tipc_bcast_get_mode(net);
2798 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2799
2800 if (!bcl)
2801 return 0;
2802
2803 tipc_bcast_lock(net);
2804
2805 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2806 NLM_F_MULTI, TIPC_NL_LINK_GET);
2807 if (!hdr) {
2808 tipc_bcast_unlock(net);
2809 return -EMSGSIZE;
2810 }
2811
2812 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2813 if (!attrs)
2814 goto msg_full;
2815
2816 /* The broadcast link is always up */
2817 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2818 goto attr_msg_full;
2819
2820 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2821 goto attr_msg_full;
2822 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2823 goto attr_msg_full;
2824 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2825 goto attr_msg_full;
2826 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2827 goto attr_msg_full;
2828
2829 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2830 if (!prop)
2831 goto attr_msg_full;
2832 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2833 goto prop_msg_full;
2834 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2835 goto prop_msg_full;
2836 if (bc_mode & BCLINK_MODE_SEL)
2837 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2838 bc_ratio))
2839 goto prop_msg_full;
2840 nla_nest_end(msg->skb, prop);
2841
2842 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2843 if (err)
2844 goto attr_msg_full;
2845
2846 tipc_bcast_unlock(net);
2847 nla_nest_end(msg->skb, attrs);
2848 genlmsg_end(msg->skb, hdr);
2849
2850 return 0;
2851
2852prop_msg_full:
2853 nla_nest_cancel(msg->skb, prop);
2854attr_msg_full:
2855 nla_nest_cancel(msg->skb, attrs);
2856msg_full:
2857 tipc_bcast_unlock(net);
2858 genlmsg_cancel(msg->skb, hdr);
2859
2860 return -EMSGSIZE;
2861}
2862
2863void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2864 struct sk_buff_head *xmitq)
2865{
2866 l->tolerance = tol;
2867 if (l->bc_rcvlink)
2868 l->bc_rcvlink->tolerance = tol;
2869 if (tipc_link_is_up(l))
2870 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2871}
2872
2873void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2874 struct sk_buff_head *xmitq)
2875{
2876 l->priority = prio;
2877 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2878}
2879
2880void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2881{
2882 l->abort_limit = limit;
2883}
2884
2885/**
2886 * tipc_link_dump - dump TIPC link data
2887 * @l: tipc link to be dumped
2888 * @dqueues: bitmask to decide if any link queue to be dumped?
2889 * - TIPC_DUMP_NONE: don't dump link queues
2890 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2891 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2892 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2893 * - TIPC_DUMP_INPUTQ: dump link input queue
2894 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2895 * - TIPC_DUMP_ALL: dump all the link queues above
2896 * @buf: returned buffer of dump data in format
2897 */
2898int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2899{
2900 int i = 0;
2901 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2902 struct sk_buff_head *list;
2903 struct sk_buff *hskb, *tskb;
2904 u32 len;
2905
2906 if (!l) {
2907 i += scnprintf(buf, sz, "link data: (null)\n");
2908 return i;
2909 }
2910
2911 i += scnprintf(buf, sz, "link data: %x", l->addr);
2912 i += scnprintf(buf + i, sz - i, " %x", l->state);
2913 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2914 i += scnprintf(buf + i, sz - i, " %u", l->session);
2915 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2916 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2917 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2918 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2919 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2920 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2921 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2922 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2923 i += scnprintf(buf + i, sz - i, " %u", 0);
2924 i += scnprintf(buf + i, sz - i, " %u", 0);
2925 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2926
2927 list = &l->transmq;
2928 len = skb_queue_len(list);
2929 hskb = skb_peek(list);
2930 tskb = skb_peek_tail(list);
2931 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2932 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2933 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2934
2935 list = &l->deferdq;
2936 len = skb_queue_len(list);
2937 hskb = skb_peek(list);
2938 tskb = skb_peek_tail(list);
2939 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2940 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2941 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2942
2943 list = &l->backlogq;
2944 len = skb_queue_len(list);
2945 hskb = skb_peek(list);
2946 tskb = skb_peek_tail(list);
2947 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2948 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2949 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2950
2951 list = l->inputq;
2952 len = skb_queue_len(list);
2953 hskb = skb_peek(list);
2954 tskb = skb_peek_tail(list);
2955 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2956 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2957 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2958
2959 if (dqueues & TIPC_DUMP_TRANSMQ) {
2960 i += scnprintf(buf + i, sz - i, "transmq: ");
2961 i += tipc_list_dump(&l->transmq, false, buf + i);
2962 }
2963 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2964 i += scnprintf(buf + i, sz - i,
2965 "backlogq: <%u %u %u %u %u>, ",
2966 l->backlog[TIPC_LOW_IMPORTANCE].len,
2967 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2968 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2969 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2970 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2971 i += tipc_list_dump(&l->backlogq, false, buf + i);
2972 }
2973 if (dqueues & TIPC_DUMP_DEFERDQ) {
2974 i += scnprintf(buf + i, sz - i, "deferdq: ");
2975 i += tipc_list_dump(&l->deferdq, false, buf + i);
2976 }
2977 if (dqueues & TIPC_DUMP_INPUTQ) {
2978 i += scnprintf(buf + i, sz - i, "inputq: ");
2979 i += tipc_list_dump(l->inputq, false, buf + i);
2980 }
2981 if (dqueues & TIPC_DUMP_WAKEUP) {
2982 i += scnprintf(buf + i, sz - i, "wakeup: ");
2983 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2984 }
2985
2986 return i;
2987}
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
47#include <linux/pkt_sched.h>
48
49struct tipc_stats {
50 u32 sent_pkts;
51 u32 recv_pkts;
52 u32 sent_states;
53 u32 recv_states;
54 u32 sent_probes;
55 u32 recv_probes;
56 u32 sent_nacks;
57 u32 recv_nacks;
58 u32 sent_acks;
59 u32 sent_bundled;
60 u32 sent_bundles;
61 u32 recv_bundled;
62 u32 recv_bundles;
63 u32 retransmitted;
64 u32 sent_fragmented;
65 u32 sent_fragments;
66 u32 recv_fragmented;
67 u32 recv_fragments;
68 u32 link_congs; /* # port sends blocked by congestion */
69 u32 deferred_recv;
70 u32 duplicates;
71 u32 max_queue_sz; /* send queue size high water mark */
72 u32 accu_queue_sz; /* used for send queue size profiling */
73 u32 queue_sz_counts; /* used for send queue size profiling */
74 u32 msg_length_counts; /* used for message length profiling */
75 u32 msg_lengths_total; /* used for message length profiling */
76 u32 msg_length_profile[7]; /* used for msg. length profiling */
77};
78
79/**
80 * struct tipc_link - TIPC link data structure
81 * @addr: network address of link's peer node
82 * @name: link name character string
83 * @media_addr: media address to use when sending messages over link
84 * @timer: link timer
85 * @net: pointer to namespace struct
86 * @refcnt: reference counter for permanent references (owner node & timer)
87 * @peer_session: link session # being used by peer end of link
88 * @peer_bearer_id: bearer id used by link's peer endpoint
89 * @bearer_id: local bearer id used by link
90 * @tolerance: minimum link continuity loss needed to reset link [in ms]
91 * @abort_limit: # of unacknowledged continuity probes needed to reset link
92 * @state: current state of link FSM
93 * @peer_caps: bitmap describing capabilities of peer node
94 * @silent_intv_cnt: # of timer intervals without any reception from peer
95 * @proto_msg: template for control messages generated by link
96 * @pmsg: convenience pointer to "proto_msg" field
97 * @priority: current link priority
98 * @net_plane: current link network plane ('A' through 'H')
99 * @mon_state: cookie with information needed by link monitor
100 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
101 * @exp_msg_count: # of tunnelled messages expected during link changeover
102 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
103 * @mtu: current maximum packet size for this link
104 * @advertised_mtu: advertised own mtu when link is being established
105 * @transmitq: queue for sent, non-acked messages
106 * @backlogq: queue for messages waiting to be sent
107 * @snt_nxt: next sequence number to use for outbound messages
108 * @last_retransmitted: sequence number of most recently retransmitted message
109 * @stale_count: # of identical retransmit requests made by peer
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 */
124struct tipc_link {
125 u32 addr;
126 char name[TIPC_MAX_LINK_NAME];
127 struct net *net;
128
129 /* Management and link supervision data */
130 u32 peer_session;
131 u32 session;
132 u32 peer_bearer_id;
133 u32 bearer_id;
134 u32 tolerance;
135 u32 abort_limit;
136 u32 state;
137 u16 peer_caps;
138 bool active;
139 u32 silent_intv_cnt;
140 char if_name[TIPC_MAX_IF_NAME];
141 u32 priority;
142 char net_plane;
143 struct tipc_mon_state mon_state;
144 u16 rst_cnt;
145
146 /* Failover/synch */
147 u16 drop_point;
148 struct sk_buff *failover_reasm_skb;
149
150 /* Max packet negotiation */
151 u16 mtu;
152 u16 advertised_mtu;
153
154 /* Sending */
155 struct sk_buff_head transmq;
156 struct sk_buff_head backlogq;
157 struct {
158 u16 len;
159 u16 limit;
160 } backlog[5];
161 u16 snd_nxt;
162 u16 last_retransm;
163 u16 window;
164 u32 stale_count;
165
166 /* Reception */
167 u16 rcv_nxt;
168 u32 rcv_unacked;
169 struct sk_buff_head deferdq;
170 struct sk_buff_head *inputq;
171 struct sk_buff_head *namedq;
172
173 /* Congestion handling */
174 struct sk_buff_head wakeupq;
175
176 /* Fragmentation/reassembly */
177 struct sk_buff *reasm_buf;
178
179 /* Broadcast */
180 u16 ackers;
181 u16 acked;
182 struct tipc_link *bc_rcvlink;
183 struct tipc_link *bc_sndlink;
184 unsigned long prev_retr;
185 u16 prev_from;
186 u16 prev_to;
187 u8 nack_state;
188 bool bc_peer_is_up;
189
190 /* Statistics */
191 struct tipc_stats stats;
192};
193
194/*
195 * Error message prefixes
196 */
197static const char *link_co_err = "Link tunneling error, ";
198static const char *link_rst_msg = "Resetting link ";
199
200/* Send states for broadcast NACKs
201 */
202enum {
203 BC_NACK_SND_CONDITIONAL,
204 BC_NACK_SND_UNCONDITIONAL,
205 BC_NACK_SND_SUPPRESS,
206};
207
208#define TIPC_BC_RETR_LIMIT 10 /* [ms] */
209
210/*
211 * Interval between NACKs when packets arrive out of order
212 */
213#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
214
215/* Wildcard value for link session numbers. When it is known that
216 * peer endpoint is down, any session number must be accepted.
217 */
218#define ANY_SESSION 0x10000
219
220/* Link FSM states:
221 */
222enum {
223 LINK_ESTABLISHED = 0xe,
224 LINK_ESTABLISHING = 0xe << 4,
225 LINK_RESET = 0x1 << 8,
226 LINK_RESETTING = 0x2 << 12,
227 LINK_PEER_RESET = 0xd << 16,
228 LINK_FAILINGOVER = 0xf << 20,
229 LINK_SYNCHING = 0xc << 24
230};
231
232/* Link FSM state checking routines
233 */
234static int link_is_up(struct tipc_link *l)
235{
236 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
237}
238
239static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
240 struct sk_buff_head *xmitq);
241static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
242 u16 rcvgap, int tolerance, int priority,
243 struct sk_buff_head *xmitq);
244static void link_print(struct tipc_link *l, const char *str);
245static int tipc_link_build_nack_msg(struct tipc_link *l,
246 struct sk_buff_head *xmitq);
247static void tipc_link_build_bc_init_msg(struct tipc_link *l,
248 struct sk_buff_head *xmitq);
249static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
250
251/*
252 * Simple non-static link routines (i.e. referenced outside this file)
253 */
254bool tipc_link_is_up(struct tipc_link *l)
255{
256 return link_is_up(l);
257}
258
259bool tipc_link_peer_is_down(struct tipc_link *l)
260{
261 return l->state == LINK_PEER_RESET;
262}
263
264bool tipc_link_is_reset(struct tipc_link *l)
265{
266 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
267}
268
269bool tipc_link_is_establishing(struct tipc_link *l)
270{
271 return l->state == LINK_ESTABLISHING;
272}
273
274bool tipc_link_is_synching(struct tipc_link *l)
275{
276 return l->state == LINK_SYNCHING;
277}
278
279bool tipc_link_is_failingover(struct tipc_link *l)
280{
281 return l->state == LINK_FAILINGOVER;
282}
283
284bool tipc_link_is_blocked(struct tipc_link *l)
285{
286 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
287}
288
289static bool link_is_bc_sndlink(struct tipc_link *l)
290{
291 return !l->bc_sndlink;
292}
293
294static bool link_is_bc_rcvlink(struct tipc_link *l)
295{
296 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
297}
298
299int tipc_link_is_active(struct tipc_link *l)
300{
301 return l->active;
302}
303
304void tipc_link_set_active(struct tipc_link *l, bool active)
305{
306 l->active = active;
307}
308
309u32 tipc_link_id(struct tipc_link *l)
310{
311 return l->peer_bearer_id << 16 | l->bearer_id;
312}
313
314int tipc_link_window(struct tipc_link *l)
315{
316 return l->window;
317}
318
319int tipc_link_prio(struct tipc_link *l)
320{
321 return l->priority;
322}
323
324unsigned long tipc_link_tolerance(struct tipc_link *l)
325{
326 return l->tolerance;
327}
328
329struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
330{
331 return l->inputq;
332}
333
334char tipc_link_plane(struct tipc_link *l)
335{
336 return l->net_plane;
337}
338
339void tipc_link_add_bc_peer(struct tipc_link *snd_l,
340 struct tipc_link *uc_l,
341 struct sk_buff_head *xmitq)
342{
343 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
344
345 snd_l->ackers++;
346 rcv_l->acked = snd_l->snd_nxt - 1;
347 snd_l->state = LINK_ESTABLISHED;
348 tipc_link_build_bc_init_msg(uc_l, xmitq);
349}
350
351void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
352 struct tipc_link *rcv_l,
353 struct sk_buff_head *xmitq)
354{
355 u16 ack = snd_l->snd_nxt - 1;
356
357 snd_l->ackers--;
358 rcv_l->bc_peer_is_up = true;
359 rcv_l->state = LINK_ESTABLISHED;
360 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
361 tipc_link_reset(rcv_l);
362 rcv_l->state = LINK_RESET;
363 if (!snd_l->ackers) {
364 tipc_link_reset(snd_l);
365 snd_l->state = LINK_RESET;
366 __skb_queue_purge(xmitq);
367 }
368}
369
370int tipc_link_bc_peers(struct tipc_link *l)
371{
372 return l->ackers;
373}
374
375u16 link_bc_rcv_gap(struct tipc_link *l)
376{
377 struct sk_buff *skb = skb_peek(&l->deferdq);
378 u16 gap = 0;
379
380 if (more(l->snd_nxt, l->rcv_nxt))
381 gap = l->snd_nxt - l->rcv_nxt;
382 if (skb)
383 gap = buf_seqno(skb) - l->rcv_nxt;
384 return gap;
385}
386
387void tipc_link_set_mtu(struct tipc_link *l, int mtu)
388{
389 l->mtu = mtu;
390}
391
392int tipc_link_mtu(struct tipc_link *l)
393{
394 return l->mtu;
395}
396
397u16 tipc_link_rcv_nxt(struct tipc_link *l)
398{
399 return l->rcv_nxt;
400}
401
402u16 tipc_link_acked(struct tipc_link *l)
403{
404 return l->acked;
405}
406
407char *tipc_link_name(struct tipc_link *l)
408{
409 return l->name;
410}
411
412/**
413 * tipc_link_create - create a new link
414 * @n: pointer to associated node
415 * @if_name: associated interface name
416 * @bearer_id: id (index) of associated bearer
417 * @tolerance: link tolerance to be used by link
418 * @net_plane: network plane (A,B,c..) this link belongs to
419 * @mtu: mtu to be advertised by link
420 * @priority: priority to be used by link
421 * @window: send window to be used by link
422 * @session: session to be used by link
423 * @ownnode: identity of own node
424 * @peer: node id of peer node
425 * @peer_caps: bitmap describing peer node capabilities
426 * @bc_sndlink: the namespace global link used for broadcast sending
427 * @bc_rcvlink: the peer specific link used for broadcast reception
428 * @inputq: queue to put messages ready for delivery
429 * @namedq: queue to put binding table update messages ready for delivery
430 * @link: return value, pointer to put the created link
431 *
432 * Returns true if link was created, otherwise false
433 */
434bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
435 int tolerance, char net_plane, u32 mtu, int priority,
436 int window, u32 session, u32 ownnode, u32 peer,
437 u16 peer_caps,
438 struct tipc_link *bc_sndlink,
439 struct tipc_link *bc_rcvlink,
440 struct sk_buff_head *inputq,
441 struct sk_buff_head *namedq,
442 struct tipc_link **link)
443{
444 struct tipc_link *l;
445
446 l = kzalloc(sizeof(*l), GFP_ATOMIC);
447 if (!l)
448 return false;
449 *link = l;
450 l->session = session;
451
452 /* Note: peer i/f name is completed by reset/activate message */
453 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
454 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
455 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
456 strcpy(l->if_name, if_name);
457 l->addr = peer;
458 l->peer_caps = peer_caps;
459 l->net = net;
460 l->peer_session = ANY_SESSION;
461 l->bearer_id = bearer_id;
462 l->tolerance = tolerance;
463 l->net_plane = net_plane;
464 l->advertised_mtu = mtu;
465 l->mtu = mtu;
466 l->priority = priority;
467 tipc_link_set_queue_limits(l, window);
468 l->ackers = 1;
469 l->bc_sndlink = bc_sndlink;
470 l->bc_rcvlink = bc_rcvlink;
471 l->inputq = inputq;
472 l->namedq = namedq;
473 l->state = LINK_RESETTING;
474 __skb_queue_head_init(&l->transmq);
475 __skb_queue_head_init(&l->backlogq);
476 __skb_queue_head_init(&l->deferdq);
477 skb_queue_head_init(&l->wakeupq);
478 skb_queue_head_init(l->inputq);
479 return true;
480}
481
482/**
483 * tipc_link_bc_create - create new link to be used for broadcast
484 * @n: pointer to associated node
485 * @mtu: mtu to be used
486 * @window: send window to be used
487 * @inputq: queue to put messages ready for delivery
488 * @namedq: queue to put binding table update messages ready for delivery
489 * @link: return value, pointer to put the created link
490 *
491 * Returns true if link was created, otherwise false
492 */
493bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
494 int mtu, int window, u16 peer_caps,
495 struct sk_buff_head *inputq,
496 struct sk_buff_head *namedq,
497 struct tipc_link *bc_sndlink,
498 struct tipc_link **link)
499{
500 struct tipc_link *l;
501
502 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
503 0, ownnode, peer, peer_caps, bc_sndlink,
504 NULL, inputq, namedq, link))
505 return false;
506
507 l = *link;
508 strcpy(l->name, tipc_bclink_name);
509 tipc_link_reset(l);
510 l->state = LINK_RESET;
511 l->ackers = 0;
512 l->bc_rcvlink = l;
513
514 /* Broadcast send link is always up */
515 if (link_is_bc_sndlink(l))
516 l->state = LINK_ESTABLISHED;
517
518 return true;
519}
520
521/**
522 * tipc_link_fsm_evt - link finite state machine
523 * @l: pointer to link
524 * @evt: state machine event to be processed
525 */
526int tipc_link_fsm_evt(struct tipc_link *l, int evt)
527{
528 int rc = 0;
529
530 switch (l->state) {
531 case LINK_RESETTING:
532 switch (evt) {
533 case LINK_PEER_RESET_EVT:
534 l->state = LINK_PEER_RESET;
535 break;
536 case LINK_RESET_EVT:
537 l->state = LINK_RESET;
538 break;
539 case LINK_FAILURE_EVT:
540 case LINK_FAILOVER_BEGIN_EVT:
541 case LINK_ESTABLISH_EVT:
542 case LINK_FAILOVER_END_EVT:
543 case LINK_SYNCH_BEGIN_EVT:
544 case LINK_SYNCH_END_EVT:
545 default:
546 goto illegal_evt;
547 }
548 break;
549 case LINK_RESET:
550 switch (evt) {
551 case LINK_PEER_RESET_EVT:
552 l->state = LINK_ESTABLISHING;
553 break;
554 case LINK_FAILOVER_BEGIN_EVT:
555 l->state = LINK_FAILINGOVER;
556 case LINK_FAILURE_EVT:
557 case LINK_RESET_EVT:
558 case LINK_ESTABLISH_EVT:
559 case LINK_FAILOVER_END_EVT:
560 break;
561 case LINK_SYNCH_BEGIN_EVT:
562 case LINK_SYNCH_END_EVT:
563 default:
564 goto illegal_evt;
565 }
566 break;
567 case LINK_PEER_RESET:
568 switch (evt) {
569 case LINK_RESET_EVT:
570 l->state = LINK_ESTABLISHING;
571 break;
572 case LINK_PEER_RESET_EVT:
573 case LINK_ESTABLISH_EVT:
574 case LINK_FAILURE_EVT:
575 break;
576 case LINK_SYNCH_BEGIN_EVT:
577 case LINK_SYNCH_END_EVT:
578 case LINK_FAILOVER_BEGIN_EVT:
579 case LINK_FAILOVER_END_EVT:
580 default:
581 goto illegal_evt;
582 }
583 break;
584 case LINK_FAILINGOVER:
585 switch (evt) {
586 case LINK_FAILOVER_END_EVT:
587 l->state = LINK_RESET;
588 break;
589 case LINK_PEER_RESET_EVT:
590 case LINK_RESET_EVT:
591 case LINK_ESTABLISH_EVT:
592 case LINK_FAILURE_EVT:
593 break;
594 case LINK_FAILOVER_BEGIN_EVT:
595 case LINK_SYNCH_BEGIN_EVT:
596 case LINK_SYNCH_END_EVT:
597 default:
598 goto illegal_evt;
599 }
600 break;
601 case LINK_ESTABLISHING:
602 switch (evt) {
603 case LINK_ESTABLISH_EVT:
604 l->state = LINK_ESTABLISHED;
605 break;
606 case LINK_FAILOVER_BEGIN_EVT:
607 l->state = LINK_FAILINGOVER;
608 break;
609 case LINK_RESET_EVT:
610 l->state = LINK_RESET;
611 break;
612 case LINK_FAILURE_EVT:
613 case LINK_PEER_RESET_EVT:
614 case LINK_SYNCH_BEGIN_EVT:
615 case LINK_FAILOVER_END_EVT:
616 break;
617 case LINK_SYNCH_END_EVT:
618 default:
619 goto illegal_evt;
620 }
621 break;
622 case LINK_ESTABLISHED:
623 switch (evt) {
624 case LINK_PEER_RESET_EVT:
625 l->state = LINK_PEER_RESET;
626 rc |= TIPC_LINK_DOWN_EVT;
627 break;
628 case LINK_FAILURE_EVT:
629 l->state = LINK_RESETTING;
630 rc |= TIPC_LINK_DOWN_EVT;
631 break;
632 case LINK_RESET_EVT:
633 l->state = LINK_RESET;
634 break;
635 case LINK_ESTABLISH_EVT:
636 case LINK_SYNCH_END_EVT:
637 break;
638 case LINK_SYNCH_BEGIN_EVT:
639 l->state = LINK_SYNCHING;
640 break;
641 case LINK_FAILOVER_BEGIN_EVT:
642 case LINK_FAILOVER_END_EVT:
643 default:
644 goto illegal_evt;
645 }
646 break;
647 case LINK_SYNCHING:
648 switch (evt) {
649 case LINK_PEER_RESET_EVT:
650 l->state = LINK_PEER_RESET;
651 rc |= TIPC_LINK_DOWN_EVT;
652 break;
653 case LINK_FAILURE_EVT:
654 l->state = LINK_RESETTING;
655 rc |= TIPC_LINK_DOWN_EVT;
656 break;
657 case LINK_RESET_EVT:
658 l->state = LINK_RESET;
659 break;
660 case LINK_ESTABLISH_EVT:
661 case LINK_SYNCH_BEGIN_EVT:
662 break;
663 case LINK_SYNCH_END_EVT:
664 l->state = LINK_ESTABLISHED;
665 break;
666 case LINK_FAILOVER_BEGIN_EVT:
667 case LINK_FAILOVER_END_EVT:
668 default:
669 goto illegal_evt;
670 }
671 break;
672 default:
673 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
674 }
675 return rc;
676illegal_evt:
677 pr_err("Illegal FSM event %x in state %x on link %s\n",
678 evt, l->state, l->name);
679 return rc;
680}
681
682/* link_profile_stats - update statistical profiling of traffic
683 */
684static void link_profile_stats(struct tipc_link *l)
685{
686 struct sk_buff *skb;
687 struct tipc_msg *msg;
688 int length;
689
690 /* Update counters used in statistical profiling of send traffic */
691 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
692 l->stats.queue_sz_counts++;
693
694 skb = skb_peek(&l->transmq);
695 if (!skb)
696 return;
697 msg = buf_msg(skb);
698 length = msg_size(msg);
699
700 if (msg_user(msg) == MSG_FRAGMENTER) {
701 if (msg_type(msg) != FIRST_FRAGMENT)
702 return;
703 length = msg_size(msg_get_wrapped(msg));
704 }
705 l->stats.msg_lengths_total += length;
706 l->stats.msg_length_counts++;
707 if (length <= 64)
708 l->stats.msg_length_profile[0]++;
709 else if (length <= 256)
710 l->stats.msg_length_profile[1]++;
711 else if (length <= 1024)
712 l->stats.msg_length_profile[2]++;
713 else if (length <= 4096)
714 l->stats.msg_length_profile[3]++;
715 else if (length <= 16384)
716 l->stats.msg_length_profile[4]++;
717 else if (length <= 32768)
718 l->stats.msg_length_profile[5]++;
719 else
720 l->stats.msg_length_profile[6]++;
721}
722
723/* tipc_link_timeout - perform periodic task as instructed from node timeout
724 */
725int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
726{
727 int mtyp = 0;
728 int rc = 0;
729 bool state = false;
730 bool probe = false;
731 bool setup = false;
732 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
733 u16 bc_acked = l->bc_rcvlink->acked;
734 struct tipc_mon_state *mstate = &l->mon_state;
735
736 switch (l->state) {
737 case LINK_ESTABLISHED:
738 case LINK_SYNCHING:
739 mtyp = STATE_MSG;
740 link_profile_stats(l);
741 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
742 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
743 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
744 state = bc_acked != bc_snt;
745 state |= l->bc_rcvlink->rcv_unacked;
746 state |= l->rcv_unacked;
747 state |= !skb_queue_empty(&l->transmq);
748 state |= !skb_queue_empty(&l->deferdq);
749 probe = mstate->probing;
750 probe |= l->silent_intv_cnt;
751 if (probe || mstate->monitoring)
752 l->silent_intv_cnt++;
753 break;
754 case LINK_RESET:
755 setup = l->rst_cnt++ <= 4;
756 setup |= !(l->rst_cnt % 16);
757 mtyp = RESET_MSG;
758 break;
759 case LINK_ESTABLISHING:
760 setup = true;
761 mtyp = ACTIVATE_MSG;
762 break;
763 case LINK_PEER_RESET:
764 case LINK_RESETTING:
765 case LINK_FAILINGOVER:
766 break;
767 default:
768 break;
769 }
770
771 if (state || probe || setup)
772 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, xmitq);
773
774 return rc;
775}
776
777/**
778 * link_schedule_user - schedule a message sender for wakeup after congestion
779 * @link: congested link
780 * @list: message that was attempted sent
781 * Create pseudo msg to send back to user when congestion abates
782 * Does not consume buffer list
783 */
784static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
785{
786 struct tipc_msg *msg = buf_msg(skb_peek(list));
787 int imp = msg_importance(msg);
788 u32 oport = msg_origport(msg);
789 u32 addr = tipc_own_addr(link->net);
790 struct sk_buff *skb;
791
792 /* This really cannot happen... */
793 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
794 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
795 return -ENOBUFS;
796 }
797 /* Non-blocking sender: */
798 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
799 return -ELINKCONG;
800
801 /* Create and schedule wakeup pseudo message */
802 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
803 addr, addr, oport, 0, 0);
804 if (!skb)
805 return -ENOBUFS;
806 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
807 TIPC_SKB_CB(skb)->chain_imp = imp;
808 skb_queue_tail(&link->wakeupq, skb);
809 link->stats.link_congs++;
810 return -ELINKCONG;
811}
812
813/**
814 * link_prepare_wakeup - prepare users for wakeup after congestion
815 * @link: congested link
816 * Move a number of waiting users, as permitted by available space in
817 * the send queue, from link wait queue to node wait queue for wakeup
818 */
819void link_prepare_wakeup(struct tipc_link *l)
820{
821 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
822 int imp, lim;
823 struct sk_buff *skb, *tmp;
824
825 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
826 imp = TIPC_SKB_CB(skb)->chain_imp;
827 lim = l->backlog[imp].limit;
828 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
829 if ((pnd[imp] + l->backlog[imp].len) >= lim)
830 break;
831 skb_unlink(skb, &l->wakeupq);
832 skb_queue_tail(l->inputq, skb);
833 }
834}
835
836void tipc_link_reset(struct tipc_link *l)
837{
838 l->peer_session = ANY_SESSION;
839 l->session++;
840 l->mtu = l->advertised_mtu;
841 __skb_queue_purge(&l->transmq);
842 __skb_queue_purge(&l->deferdq);
843 skb_queue_splice_init(&l->wakeupq, l->inputq);
844 __skb_queue_purge(&l->backlogq);
845 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
846 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
847 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
848 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
849 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
850 kfree_skb(l->reasm_buf);
851 kfree_skb(l->failover_reasm_skb);
852 l->reasm_buf = NULL;
853 l->failover_reasm_skb = NULL;
854 l->rcv_unacked = 0;
855 l->snd_nxt = 1;
856 l->rcv_nxt = 1;
857 l->acked = 0;
858 l->silent_intv_cnt = 0;
859 l->rst_cnt = 0;
860 l->stale_count = 0;
861 l->bc_peer_is_up = false;
862 memset(&l->mon_state, 0, sizeof(l->mon_state));
863 tipc_link_reset_stats(l);
864}
865
866/**
867 * tipc_link_xmit(): enqueue buffer list according to queue situation
868 * @link: link to use
869 * @list: chain of buffers containing message
870 * @xmitq: returned list of packets to be sent by caller
871 *
872 * Consumes the buffer chain, except when returning -ELINKCONG,
873 * since the caller then may want to make more send attempts.
874 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
875 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
876 */
877int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
878 struct sk_buff_head *xmitq)
879{
880 struct tipc_msg *hdr = buf_msg(skb_peek(list));
881 unsigned int maxwin = l->window;
882 unsigned int i, imp = msg_importance(hdr);
883 unsigned int mtu = l->mtu;
884 u16 ack = l->rcv_nxt - 1;
885 u16 seqno = l->snd_nxt;
886 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
887 struct sk_buff_head *transmq = &l->transmq;
888 struct sk_buff_head *backlogq = &l->backlogq;
889 struct sk_buff *skb, *_skb, *bskb;
890 int pkt_cnt = skb_queue_len(list);
891
892 /* Match msg importance against this and all higher backlog limits: */
893 if (!skb_queue_empty(backlogq)) {
894 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
895 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
896 return link_schedule_user(l, list);
897 }
898 }
899 if (unlikely(msg_size(hdr) > mtu)) {
900 skb_queue_purge(list);
901 return -EMSGSIZE;
902 }
903
904 if (pkt_cnt > 1) {
905 l->stats.sent_fragmented++;
906 l->stats.sent_fragments += pkt_cnt;
907 }
908
909 /* Prepare each packet for sending, and add to relevant queue: */
910 while (skb_queue_len(list)) {
911 skb = skb_peek(list);
912 hdr = buf_msg(skb);
913 msg_set_seqno(hdr, seqno);
914 msg_set_ack(hdr, ack);
915 msg_set_bcast_ack(hdr, bc_ack);
916
917 if (likely(skb_queue_len(transmq) < maxwin)) {
918 _skb = skb_clone(skb, GFP_ATOMIC);
919 if (!_skb) {
920 skb_queue_purge(list);
921 return -ENOBUFS;
922 }
923 __skb_dequeue(list);
924 __skb_queue_tail(transmq, skb);
925 __skb_queue_tail(xmitq, _skb);
926 TIPC_SKB_CB(skb)->ackers = l->ackers;
927 l->rcv_unacked = 0;
928 l->stats.sent_pkts++;
929 seqno++;
930 continue;
931 }
932 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
933 kfree_skb(__skb_dequeue(list));
934 l->stats.sent_bundled++;
935 continue;
936 }
937 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
938 kfree_skb(__skb_dequeue(list));
939 __skb_queue_tail(backlogq, bskb);
940 l->backlog[msg_importance(buf_msg(bskb))].len++;
941 l->stats.sent_bundled++;
942 l->stats.sent_bundles++;
943 continue;
944 }
945 l->backlog[imp].len += skb_queue_len(list);
946 skb_queue_splice_tail_init(list, backlogq);
947 }
948 l->snd_nxt = seqno;
949 return 0;
950}
951
952void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
953{
954 struct sk_buff *skb, *_skb;
955 struct tipc_msg *hdr;
956 u16 seqno = l->snd_nxt;
957 u16 ack = l->rcv_nxt - 1;
958 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
959
960 while (skb_queue_len(&l->transmq) < l->window) {
961 skb = skb_peek(&l->backlogq);
962 if (!skb)
963 break;
964 _skb = skb_clone(skb, GFP_ATOMIC);
965 if (!_skb)
966 break;
967 __skb_dequeue(&l->backlogq);
968 hdr = buf_msg(skb);
969 l->backlog[msg_importance(hdr)].len--;
970 __skb_queue_tail(&l->transmq, skb);
971 __skb_queue_tail(xmitq, _skb);
972 TIPC_SKB_CB(skb)->ackers = l->ackers;
973 msg_set_seqno(hdr, seqno);
974 msg_set_ack(hdr, ack);
975 msg_set_bcast_ack(hdr, bc_ack);
976 l->rcv_unacked = 0;
977 l->stats.sent_pkts++;
978 seqno++;
979 }
980 l->snd_nxt = seqno;
981}
982
983static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
984{
985 struct tipc_msg *hdr = buf_msg(skb);
986
987 pr_warn("Retransmission failure on link <%s>\n", l->name);
988 link_print(l, "Resetting link ");
989 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
990 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
991 pr_info("sqno %u, prev: %x, src: %x\n",
992 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
993}
994
995int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
996 struct sk_buff_head *xmitq)
997{
998 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
999 struct tipc_msg *hdr;
1000 u16 ack = l->rcv_nxt - 1;
1001 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1002
1003 if (!skb)
1004 return 0;
1005
1006 /* Detect repeated retransmit failures on same packet */
1007 if (likely(l->last_retransm != buf_seqno(skb))) {
1008 l->last_retransm = buf_seqno(skb);
1009 l->stale_count = 1;
1010 } else if (++l->stale_count > 100) {
1011 link_retransmit_failure(l, skb);
1012 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1013 }
1014
1015 /* Move forward to where retransmission should start */
1016 skb_queue_walk(&l->transmq, skb) {
1017 if (!less(buf_seqno(skb), from))
1018 break;
1019 }
1020
1021 skb_queue_walk_from(&l->transmq, skb) {
1022 if (more(buf_seqno(skb), to))
1023 break;
1024 hdr = buf_msg(skb);
1025 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
1026 if (!_skb)
1027 return 0;
1028 hdr = buf_msg(_skb);
1029 msg_set_ack(hdr, ack);
1030 msg_set_bcast_ack(hdr, bc_ack);
1031 _skb->priority = TC_PRIO_CONTROL;
1032 __skb_queue_tail(xmitq, _skb);
1033 l->stats.retransmitted++;
1034 }
1035 return 0;
1036}
1037
1038/* tipc_data_input - deliver data and name distr msgs to upper layer
1039 *
1040 * Consumes buffer if message is of right type
1041 * Node lock must be held
1042 */
1043static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1044 struct sk_buff_head *inputq)
1045{
1046 switch (msg_user(buf_msg(skb))) {
1047 case TIPC_LOW_IMPORTANCE:
1048 case TIPC_MEDIUM_IMPORTANCE:
1049 case TIPC_HIGH_IMPORTANCE:
1050 case TIPC_CRITICAL_IMPORTANCE:
1051 case CONN_MANAGER:
1052 skb_queue_tail(inputq, skb);
1053 return true;
1054 case NAME_DISTRIBUTOR:
1055 l->bc_rcvlink->state = LINK_ESTABLISHED;
1056 skb_queue_tail(l->namedq, skb);
1057 return true;
1058 case MSG_BUNDLER:
1059 case TUNNEL_PROTOCOL:
1060 case MSG_FRAGMENTER:
1061 case BCAST_PROTOCOL:
1062 return false;
1063 default:
1064 pr_warn("Dropping received illegal msg type\n");
1065 kfree_skb(skb);
1066 return false;
1067 };
1068}
1069
1070/* tipc_link_input - process packet that has passed link protocol check
1071 *
1072 * Consumes buffer
1073 */
1074static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1075 struct sk_buff_head *inputq)
1076{
1077 struct tipc_msg *hdr = buf_msg(skb);
1078 struct sk_buff **reasm_skb = &l->reasm_buf;
1079 struct sk_buff *iskb;
1080 struct sk_buff_head tmpq;
1081 int usr = msg_user(hdr);
1082 int rc = 0;
1083 int pos = 0;
1084 int ipos = 0;
1085
1086 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1087 if (msg_type(hdr) == SYNCH_MSG) {
1088 __skb_queue_purge(&l->deferdq);
1089 goto drop;
1090 }
1091 if (!tipc_msg_extract(skb, &iskb, &ipos))
1092 return rc;
1093 kfree_skb(skb);
1094 skb = iskb;
1095 hdr = buf_msg(skb);
1096 if (less(msg_seqno(hdr), l->drop_point))
1097 goto drop;
1098 if (tipc_data_input(l, skb, inputq))
1099 return rc;
1100 usr = msg_user(hdr);
1101 reasm_skb = &l->failover_reasm_skb;
1102 }
1103
1104 if (usr == MSG_BUNDLER) {
1105 skb_queue_head_init(&tmpq);
1106 l->stats.recv_bundles++;
1107 l->stats.recv_bundled += msg_msgcnt(hdr);
1108 while (tipc_msg_extract(skb, &iskb, &pos))
1109 tipc_data_input(l, iskb, &tmpq);
1110 tipc_skb_queue_splice_tail(&tmpq, inputq);
1111 return 0;
1112 } else if (usr == MSG_FRAGMENTER) {
1113 l->stats.recv_fragments++;
1114 if (tipc_buf_append(reasm_skb, &skb)) {
1115 l->stats.recv_fragmented++;
1116 tipc_data_input(l, skb, inputq);
1117 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1118 pr_warn_ratelimited("Unable to build fragment list\n");
1119 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1120 }
1121 return 0;
1122 } else if (usr == BCAST_PROTOCOL) {
1123 tipc_bcast_lock(l->net);
1124 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1125 tipc_bcast_unlock(l->net);
1126 }
1127drop:
1128 kfree_skb(skb);
1129 return 0;
1130}
1131
1132static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1133{
1134 bool released = false;
1135 struct sk_buff *skb, *tmp;
1136
1137 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1138 if (more(buf_seqno(skb), acked))
1139 break;
1140 __skb_unlink(skb, &l->transmq);
1141 kfree_skb(skb);
1142 released = true;
1143 }
1144 return released;
1145}
1146
1147/* tipc_link_build_state_msg: prepare link state message for transmission
1148 *
1149 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1150 * risk of ack storms towards the sender
1151 */
1152int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1153{
1154 if (!l)
1155 return 0;
1156
1157 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1158 if (link_is_bc_rcvlink(l)) {
1159 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1160 return 0;
1161 l->rcv_unacked = 0;
1162
1163 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1164 l->snd_nxt = l->rcv_nxt;
1165 return TIPC_LINK_SND_STATE;
1166 }
1167
1168 /* Unicast ACK */
1169 l->rcv_unacked = 0;
1170 l->stats.sent_acks++;
1171 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1172 return 0;
1173}
1174
1175/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1176 */
1177void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1178{
1179 int mtyp = RESET_MSG;
1180 struct sk_buff *skb;
1181
1182 if (l->state == LINK_ESTABLISHING)
1183 mtyp = ACTIVATE_MSG;
1184
1185 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
1186
1187 /* Inform peer that this endpoint is going down if applicable */
1188 skb = skb_peek_tail(xmitq);
1189 if (skb && (l->state == LINK_RESET))
1190 msg_set_peer_stopping(buf_msg(skb), 1);
1191}
1192
1193/* tipc_link_build_nack_msg: prepare link nack message for transmission
1194 * Note that sending of broadcast NACK is coordinated among nodes, to
1195 * reduce the risk of NACK storms towards the sender
1196 */
1197static int tipc_link_build_nack_msg(struct tipc_link *l,
1198 struct sk_buff_head *xmitq)
1199{
1200 u32 def_cnt = ++l->stats.deferred_recv;
1201 int match1, match2;
1202
1203 if (link_is_bc_rcvlink(l)) {
1204 match1 = def_cnt & 0xf;
1205 match2 = tipc_own_addr(l->net) & 0xf;
1206 if (match1 == match2)
1207 return TIPC_LINK_SND_STATE;
1208 return 0;
1209 }
1210
1211 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1212 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1213 return 0;
1214}
1215
1216/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1217 * @l: the link that should handle the message
1218 * @skb: TIPC packet
1219 * @xmitq: queue to place packets to be sent after this call
1220 */
1221int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1222 struct sk_buff_head *xmitq)
1223{
1224 struct sk_buff_head *defq = &l->deferdq;
1225 struct tipc_msg *hdr;
1226 u16 seqno, rcv_nxt, win_lim;
1227 int rc = 0;
1228
1229 do {
1230 hdr = buf_msg(skb);
1231 seqno = msg_seqno(hdr);
1232 rcv_nxt = l->rcv_nxt;
1233 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1234
1235 /* Verify and update link state */
1236 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1237 return tipc_link_proto_rcv(l, skb, xmitq);
1238
1239 if (unlikely(!link_is_up(l))) {
1240 if (l->state == LINK_ESTABLISHING)
1241 rc = TIPC_LINK_UP_EVT;
1242 goto drop;
1243 }
1244
1245 /* Don't send probe at next timeout expiration */
1246 l->silent_intv_cnt = 0;
1247
1248 /* Drop if outside receive window */
1249 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1250 l->stats.duplicates++;
1251 goto drop;
1252 }
1253
1254 /* Forward queues and wake up waiting users */
1255 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1256 tipc_link_advance_backlog(l, xmitq);
1257 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1258 link_prepare_wakeup(l);
1259 }
1260
1261 /* Defer delivery if sequence gap */
1262 if (unlikely(seqno != rcv_nxt)) {
1263 __tipc_skb_queue_sorted(defq, seqno, skb);
1264 rc |= tipc_link_build_nack_msg(l, xmitq);
1265 break;
1266 }
1267
1268 /* Deliver packet */
1269 l->rcv_nxt++;
1270 l->stats.recv_pkts++;
1271 if (!tipc_data_input(l, skb, l->inputq))
1272 rc |= tipc_link_input(l, skb, l->inputq);
1273 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1274 rc |= tipc_link_build_state_msg(l, xmitq);
1275 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1276 break;
1277 } while ((skb = __skb_dequeue(defq)));
1278
1279 return rc;
1280drop:
1281 kfree_skb(skb);
1282 return rc;
1283}
1284
1285static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1286 u16 rcvgap, int tolerance, int priority,
1287 struct sk_buff_head *xmitq)
1288{
1289 struct tipc_link *bcl = l->bc_rcvlink;
1290 struct sk_buff *skb;
1291 struct tipc_msg *hdr;
1292 struct sk_buff_head *dfq = &l->deferdq;
1293 bool node_up = link_is_up(bcl);
1294 struct tipc_mon_state *mstate = &l->mon_state;
1295 int dlen = 0;
1296 void *data;
1297
1298 /* Don't send protocol message during reset or link failover */
1299 if (tipc_link_is_blocked(l))
1300 return;
1301
1302 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1303 return;
1304
1305 if (!skb_queue_empty(dfq))
1306 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1307
1308 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1309 tipc_max_domain_size, l->addr,
1310 tipc_own_addr(l->net), 0, 0, 0);
1311 if (!skb)
1312 return;
1313
1314 hdr = buf_msg(skb);
1315 data = msg_data(hdr);
1316 msg_set_session(hdr, l->session);
1317 msg_set_bearer_id(hdr, l->bearer_id);
1318 msg_set_net_plane(hdr, l->net_plane);
1319 msg_set_next_sent(hdr, l->snd_nxt);
1320 msg_set_ack(hdr, l->rcv_nxt - 1);
1321 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1322 msg_set_bc_ack_invalid(hdr, !node_up);
1323 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1324 msg_set_link_tolerance(hdr, tolerance);
1325 msg_set_linkprio(hdr, priority);
1326 msg_set_redundant_link(hdr, node_up);
1327 msg_set_seq_gap(hdr, 0);
1328 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1329
1330 if (mtyp == STATE_MSG) {
1331 msg_set_seq_gap(hdr, rcvgap);
1332 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1333 msg_set_probe(hdr, probe);
1334 tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id);
1335 msg_set_size(hdr, INT_H_SIZE + dlen);
1336 skb_trim(skb, INT_H_SIZE + dlen);
1337 l->stats.sent_states++;
1338 l->rcv_unacked = 0;
1339 } else {
1340 /* RESET_MSG or ACTIVATE_MSG */
1341 msg_set_max_pkt(hdr, l->advertised_mtu);
1342 strcpy(data, l->if_name);
1343 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1344 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1345 }
1346 if (probe)
1347 l->stats.sent_probes++;
1348 if (rcvgap)
1349 l->stats.sent_nacks++;
1350 skb->priority = TC_PRIO_CONTROL;
1351 __skb_queue_tail(xmitq, skb);
1352}
1353
1354/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1355 * with contents of the link's transmit and backlog queues.
1356 */
1357void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1358 int mtyp, struct sk_buff_head *xmitq)
1359{
1360 struct sk_buff *skb, *tnlskb;
1361 struct tipc_msg *hdr, tnlhdr;
1362 struct sk_buff_head *queue = &l->transmq;
1363 struct sk_buff_head tmpxq, tnlq;
1364 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1365
1366 if (!tnl)
1367 return;
1368
1369 skb_queue_head_init(&tnlq);
1370 skb_queue_head_init(&tmpxq);
1371
1372 /* At least one packet required for safe algorithm => add dummy */
1373 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1374 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1375 0, 0, TIPC_ERR_NO_PORT);
1376 if (!skb) {
1377 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1378 return;
1379 }
1380 skb_queue_tail(&tnlq, skb);
1381 tipc_link_xmit(l, &tnlq, &tmpxq);
1382 __skb_queue_purge(&tmpxq);
1383
1384 /* Initialize reusable tunnel packet header */
1385 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1386 mtyp, INT_H_SIZE, l->addr);
1387 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1388 msg_set_msgcnt(&tnlhdr, pktcnt);
1389 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1390tnl:
1391 /* Wrap each packet into a tunnel packet */
1392 skb_queue_walk(queue, skb) {
1393 hdr = buf_msg(skb);
1394 if (queue == &l->backlogq)
1395 msg_set_seqno(hdr, seqno++);
1396 pktlen = msg_size(hdr);
1397 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1398 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
1399 if (!tnlskb) {
1400 pr_warn("%sunable to send packet\n", link_co_err);
1401 return;
1402 }
1403 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1404 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1405 __skb_queue_tail(&tnlq, tnlskb);
1406 }
1407 if (queue != &l->backlogq) {
1408 queue = &l->backlogq;
1409 goto tnl;
1410 }
1411
1412 tipc_link_xmit(tnl, &tnlq, xmitq);
1413
1414 if (mtyp == FAILOVER_MSG) {
1415 tnl->drop_point = l->rcv_nxt;
1416 tnl->failover_reasm_skb = l->reasm_buf;
1417 l->reasm_buf = NULL;
1418 }
1419}
1420
1421/* tipc_link_proto_rcv(): receive link level protocol message :
1422 * Note that network plane id propagates through the network, and may
1423 * change at any time. The node with lowest numerical id determines
1424 * network plane
1425 */
1426static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1427 struct sk_buff_head *xmitq)
1428{
1429 struct tipc_msg *hdr = buf_msg(skb);
1430 u16 rcvgap = 0;
1431 u16 ack = msg_ack(hdr);
1432 u16 gap = msg_seq_gap(hdr);
1433 u16 peers_snd_nxt = msg_next_sent(hdr);
1434 u16 peers_tol = msg_link_tolerance(hdr);
1435 u16 peers_prio = msg_linkprio(hdr);
1436 u16 rcv_nxt = l->rcv_nxt;
1437 u16 dlen = msg_data_sz(hdr);
1438 int mtyp = msg_type(hdr);
1439 void *data;
1440 char *if_name;
1441 int rc = 0;
1442
1443 if (tipc_link_is_blocked(l) || !xmitq)
1444 goto exit;
1445
1446 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1447 l->net_plane = msg_net_plane(hdr);
1448
1449 skb_linearize(skb);
1450 hdr = buf_msg(skb);
1451 data = msg_data(hdr);
1452
1453 switch (mtyp) {
1454 case RESET_MSG:
1455
1456 /* Ignore duplicate RESET with old session number */
1457 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1458 (l->peer_session != ANY_SESSION))
1459 break;
1460 /* fall thru' */
1461
1462 case ACTIVATE_MSG:
1463
1464 /* Complete own link name with peer's interface name */
1465 if_name = strrchr(l->name, ':') + 1;
1466 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1467 break;
1468 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1469 break;
1470 strncpy(if_name, data, TIPC_MAX_IF_NAME);
1471
1472 /* Update own tolerance if peer indicates a non-zero value */
1473 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1474 l->tolerance = peers_tol;
1475
1476 /* Update own priority if peer's priority is higher */
1477 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1478 l->priority = peers_prio;
1479
1480 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1481 if (msg_peer_stopping(hdr))
1482 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1483 else if ((mtyp == RESET_MSG) || !link_is_up(l))
1484 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1485
1486 /* ACTIVATE_MSG takes up link if it was already locally reset */
1487 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1488 rc = TIPC_LINK_UP_EVT;
1489
1490 l->peer_session = msg_session(hdr);
1491 l->peer_bearer_id = msg_bearer_id(hdr);
1492 if (l->mtu > msg_max_pkt(hdr))
1493 l->mtu = msg_max_pkt(hdr);
1494 break;
1495
1496 case STATE_MSG:
1497
1498 /* Update own tolerance if peer indicates a non-zero value */
1499 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1500 l->tolerance = peers_tol;
1501
1502 /* Update own prio if peer indicates a different value */
1503 if ((peers_prio != l->priority) &&
1504 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
1505 l->priority = peers_prio;
1506 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1507 }
1508
1509 l->silent_intv_cnt = 0;
1510 l->stats.recv_states++;
1511 if (msg_probe(hdr))
1512 l->stats.recv_probes++;
1513
1514 if (!link_is_up(l)) {
1515 if (l->state == LINK_ESTABLISHING)
1516 rc = TIPC_LINK_UP_EVT;
1517 break;
1518 }
1519 tipc_mon_rcv(l->net, data, dlen, l->addr,
1520 &l->mon_state, l->bearer_id);
1521
1522 /* Send NACK if peer has sent pkts we haven't received yet */
1523 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1524 rcvgap = peers_snd_nxt - l->rcv_nxt;
1525 if (rcvgap || (msg_probe(hdr)))
1526 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1527 0, 0, xmitq);
1528 tipc_link_release_pkts(l, ack);
1529
1530 /* If NACK, retransmit will now start at right position */
1531 if (gap) {
1532 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1533 l->stats.recv_nacks++;
1534 }
1535
1536 tipc_link_advance_backlog(l, xmitq);
1537 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1538 link_prepare_wakeup(l);
1539 }
1540exit:
1541 kfree_skb(skb);
1542 return rc;
1543}
1544
1545/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1546 */
1547static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1548 u16 peers_snd_nxt,
1549 struct sk_buff_head *xmitq)
1550{
1551 struct sk_buff *skb;
1552 struct tipc_msg *hdr;
1553 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1554 u16 ack = l->rcv_nxt - 1;
1555 u16 gap_to = peers_snd_nxt - 1;
1556
1557 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1558 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
1559 if (!skb)
1560 return false;
1561 hdr = buf_msg(skb);
1562 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1563 msg_set_bcast_ack(hdr, ack);
1564 msg_set_bcgap_after(hdr, ack);
1565 if (dfrd_skb)
1566 gap_to = buf_seqno(dfrd_skb) - 1;
1567 msg_set_bcgap_to(hdr, gap_to);
1568 msg_set_non_seq(hdr, bcast);
1569 __skb_queue_tail(xmitq, skb);
1570 return true;
1571}
1572
1573/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1574 *
1575 * Give a newly added peer node the sequence number where it should
1576 * start receiving and acking broadcast packets.
1577 */
1578static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1579 struct sk_buff_head *xmitq)
1580{
1581 struct sk_buff_head list;
1582
1583 __skb_queue_head_init(&list);
1584 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1585 return;
1586 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
1587 tipc_link_xmit(l, &list, xmitq);
1588}
1589
1590/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1591 */
1592void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1593{
1594 int mtyp = msg_type(hdr);
1595 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1596
1597 if (link_is_up(l))
1598 return;
1599
1600 if (msg_user(hdr) == BCAST_PROTOCOL) {
1601 l->rcv_nxt = peers_snd_nxt;
1602 l->state = LINK_ESTABLISHED;
1603 return;
1604 }
1605
1606 if (l->peer_caps & TIPC_BCAST_SYNCH)
1607 return;
1608
1609 if (msg_peer_node_is_up(hdr))
1610 return;
1611
1612 /* Compatibility: accept older, less safe initial synch data */
1613 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1614 l->rcv_nxt = peers_snd_nxt;
1615}
1616
1617/* link_bc_retr eval()- check if the indicated range can be retransmitted now
1618 * - Adjust permitted range if there is overlap with previous retransmission
1619 */
1620static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to)
1621{
1622 unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr);
1623
1624 if (less(*to, *from))
1625 return false;
1626
1627 /* New retransmission request */
1628 if ((elapsed > TIPC_BC_RETR_LIMIT) ||
1629 less(*to, l->prev_from) || more(*from, l->prev_to)) {
1630 l->prev_from = *from;
1631 l->prev_to = *to;
1632 l->prev_retr = jiffies;
1633 return true;
1634 }
1635
1636 /* Inside range of previous retransmit */
1637 if (!less(*from, l->prev_from) && !more(*to, l->prev_to))
1638 return false;
1639
1640 /* Fully or partially outside previous range => exclude overlap */
1641 if (less(*from, l->prev_from)) {
1642 *to = l->prev_from - 1;
1643 l->prev_from = *from;
1644 }
1645 if (more(*to, l->prev_to)) {
1646 *from = l->prev_to + 1;
1647 l->prev_to = *to;
1648 }
1649 l->prev_retr = jiffies;
1650 return true;
1651}
1652
1653/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1654 */
1655int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1656 struct sk_buff_head *xmitq)
1657{
1658 struct tipc_link *snd_l = l->bc_sndlink;
1659 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1660 u16 from = msg_bcast_ack(hdr) + 1;
1661 u16 to = from + msg_bc_gap(hdr) - 1;
1662 int rc = 0;
1663
1664 if (!link_is_up(l))
1665 return rc;
1666
1667 if (!msg_peer_node_is_up(hdr))
1668 return rc;
1669
1670 /* Open when peer ackowledges our bcast init msg (pkt #1) */
1671 if (msg_ack(hdr))
1672 l->bc_peer_is_up = true;
1673
1674 if (!l->bc_peer_is_up)
1675 return rc;
1676
1677 l->stats.recv_nacks++;
1678
1679 /* Ignore if peers_snd_nxt goes beyond receive window */
1680 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1681 return rc;
1682
1683 if (link_bc_retr_eval(snd_l, &from, &to))
1684 rc = tipc_link_retrans(snd_l, from, to, xmitq);
1685
1686 l->snd_nxt = peers_snd_nxt;
1687 if (link_bc_rcv_gap(l))
1688 rc |= TIPC_LINK_SND_STATE;
1689
1690 /* Return now if sender supports nack via STATE messages */
1691 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
1692 return rc;
1693
1694 /* Otherwise, be backwards compatible */
1695
1696 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1697 l->nack_state = BC_NACK_SND_CONDITIONAL;
1698 return 0;
1699 }
1700
1701 /* Don't NACK if one was recently sent or peeked */
1702 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1703 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1704 return 0;
1705 }
1706
1707 /* Conditionally delay NACK sending until next synch rcv */
1708 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1709 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1710 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1711 return 0;
1712 }
1713
1714 /* Send NACK now but suppress next one */
1715 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1716 l->nack_state = BC_NACK_SND_SUPPRESS;
1717 return 0;
1718}
1719
1720void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1721 struct sk_buff_head *xmitq)
1722{
1723 struct sk_buff *skb, *tmp;
1724 struct tipc_link *snd_l = l->bc_sndlink;
1725
1726 if (!link_is_up(l) || !l->bc_peer_is_up)
1727 return;
1728
1729 if (!more(acked, l->acked))
1730 return;
1731
1732 /* Skip over packets peer has already acked */
1733 skb_queue_walk(&snd_l->transmq, skb) {
1734 if (more(buf_seqno(skb), l->acked))
1735 break;
1736 }
1737
1738 /* Update/release the packets peer is acking now */
1739 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1740 if (more(buf_seqno(skb), acked))
1741 break;
1742 if (!--TIPC_SKB_CB(skb)->ackers) {
1743 __skb_unlink(skb, &snd_l->transmq);
1744 kfree_skb(skb);
1745 }
1746 }
1747 l->acked = acked;
1748 tipc_link_advance_backlog(snd_l, xmitq);
1749 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1750 link_prepare_wakeup(snd_l);
1751}
1752
1753/* tipc_link_bc_nack_rcv(): receive broadcast nack message
1754 * This function is here for backwards compatibility, since
1755 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
1756 */
1757int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1758 struct sk_buff_head *xmitq)
1759{
1760 struct tipc_msg *hdr = buf_msg(skb);
1761 u32 dnode = msg_destnode(hdr);
1762 int mtyp = msg_type(hdr);
1763 u16 acked = msg_bcast_ack(hdr);
1764 u16 from = acked + 1;
1765 u16 to = msg_bcgap_to(hdr);
1766 u16 peers_snd_nxt = to + 1;
1767 int rc = 0;
1768
1769 kfree_skb(skb);
1770
1771 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1772 return 0;
1773
1774 if (mtyp != STATE_MSG)
1775 return 0;
1776
1777 if (dnode == tipc_own_addr(l->net)) {
1778 tipc_link_bc_ack_rcv(l, acked, xmitq);
1779 rc = tipc_link_retrans(l->bc_sndlink, from, to, xmitq);
1780 l->stats.recv_nacks++;
1781 return rc;
1782 }
1783
1784 /* Msg for other node => suppress own NACK at next sync if applicable */
1785 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1786 l->nack_state = BC_NACK_SND_SUPPRESS;
1787
1788 return 0;
1789}
1790
1791void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1792{
1793 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1794
1795 l->window = win;
1796 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win);
1797 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2);
1798 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3);
1799 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4);
1800 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1801}
1802
1803/**
1804 * link_reset_stats - reset link statistics
1805 * @l: pointer to link
1806 */
1807void tipc_link_reset_stats(struct tipc_link *l)
1808{
1809 memset(&l->stats, 0, sizeof(l->stats));
1810}
1811
1812static void link_print(struct tipc_link *l, const char *str)
1813{
1814 struct sk_buff *hskb = skb_peek(&l->transmq);
1815 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1816 u16 tail = l->snd_nxt - 1;
1817
1818 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1819 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1820 skb_queue_len(&l->transmq), head, tail,
1821 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1822}
1823
1824/* Parse and validate nested (link) properties valid for media, bearer and link
1825 */
1826int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1827{
1828 int err;
1829
1830 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1831 tipc_nl_prop_policy);
1832 if (err)
1833 return err;
1834
1835 if (props[TIPC_NLA_PROP_PRIO]) {
1836 u32 prio;
1837
1838 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1839 if (prio > TIPC_MAX_LINK_PRI)
1840 return -EINVAL;
1841 }
1842
1843 if (props[TIPC_NLA_PROP_TOL]) {
1844 u32 tol;
1845
1846 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1847 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1848 return -EINVAL;
1849 }
1850
1851 if (props[TIPC_NLA_PROP_WIN]) {
1852 u32 win;
1853
1854 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1855 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1856 return -EINVAL;
1857 }
1858
1859 return 0;
1860}
1861
1862static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1863{
1864 int i;
1865 struct nlattr *stats;
1866
1867 struct nla_map {
1868 u32 key;
1869 u32 val;
1870 };
1871
1872 struct nla_map map[] = {
1873 {TIPC_NLA_STATS_RX_INFO, 0},
1874 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1875 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1876 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1877 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1878 {TIPC_NLA_STATS_TX_INFO, 0},
1879 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1880 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1881 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1882 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1883 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1884 s->msg_length_counts : 1},
1885 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1886 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1887 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1888 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1889 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1890 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1891 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1892 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1893 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1894 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1895 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1896 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1897 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1898 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1899 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1900 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1901 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1902 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1903 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1904 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1905 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1906 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1907 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1908 };
1909
1910 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1911 if (!stats)
1912 return -EMSGSIZE;
1913
1914 for (i = 0; i < ARRAY_SIZE(map); i++)
1915 if (nla_put_u32(skb, map[i].key, map[i].val))
1916 goto msg_full;
1917
1918 nla_nest_end(skb, stats);
1919
1920 return 0;
1921msg_full:
1922 nla_nest_cancel(skb, stats);
1923
1924 return -EMSGSIZE;
1925}
1926
1927/* Caller should hold appropriate locks to protect the link */
1928int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1929 struct tipc_link *link, int nlflags)
1930{
1931 int err;
1932 void *hdr;
1933 struct nlattr *attrs;
1934 struct nlattr *prop;
1935 struct tipc_net *tn = net_generic(net, tipc_net_id);
1936
1937 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1938 nlflags, TIPC_NL_LINK_GET);
1939 if (!hdr)
1940 return -EMSGSIZE;
1941
1942 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1943 if (!attrs)
1944 goto msg_full;
1945
1946 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1947 goto attr_msg_full;
1948 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1949 tipc_cluster_mask(tn->own_addr)))
1950 goto attr_msg_full;
1951 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1952 goto attr_msg_full;
1953 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
1954 goto attr_msg_full;
1955 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
1956 goto attr_msg_full;
1957
1958 if (tipc_link_is_up(link))
1959 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1960 goto attr_msg_full;
1961 if (link->active)
1962 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1963 goto attr_msg_full;
1964
1965 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1966 if (!prop)
1967 goto attr_msg_full;
1968 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1969 goto prop_msg_full;
1970 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1971 goto prop_msg_full;
1972 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1973 link->window))
1974 goto prop_msg_full;
1975 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1976 goto prop_msg_full;
1977 nla_nest_end(msg->skb, prop);
1978
1979 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1980 if (err)
1981 goto attr_msg_full;
1982
1983 nla_nest_end(msg->skb, attrs);
1984 genlmsg_end(msg->skb, hdr);
1985
1986 return 0;
1987
1988prop_msg_full:
1989 nla_nest_cancel(msg->skb, prop);
1990attr_msg_full:
1991 nla_nest_cancel(msg->skb, attrs);
1992msg_full:
1993 genlmsg_cancel(msg->skb, hdr);
1994
1995 return -EMSGSIZE;
1996}
1997
1998static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
1999 struct tipc_stats *stats)
2000{
2001 int i;
2002 struct nlattr *nest;
2003
2004 struct nla_map {
2005 __u32 key;
2006 __u32 val;
2007 };
2008
2009 struct nla_map map[] = {
2010 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2011 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2012 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2013 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2014 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2015 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2016 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2017 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2018 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2019 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2020 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2021 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2022 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2023 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2024 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2025 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2026 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2027 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2028 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2029 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2030 };
2031
2032 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
2033 if (!nest)
2034 return -EMSGSIZE;
2035
2036 for (i = 0; i < ARRAY_SIZE(map); i++)
2037 if (nla_put_u32(skb, map[i].key, map[i].val))
2038 goto msg_full;
2039
2040 nla_nest_end(skb, nest);
2041
2042 return 0;
2043msg_full:
2044 nla_nest_cancel(skb, nest);
2045
2046 return -EMSGSIZE;
2047}
2048
2049int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
2050{
2051 int err;
2052 void *hdr;
2053 struct nlattr *attrs;
2054 struct nlattr *prop;
2055 struct tipc_net *tn = net_generic(net, tipc_net_id);
2056 struct tipc_link *bcl = tn->bcl;
2057
2058 if (!bcl)
2059 return 0;
2060
2061 tipc_bcast_lock(net);
2062
2063 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2064 NLM_F_MULTI, TIPC_NL_LINK_GET);
2065 if (!hdr) {
2066 tipc_bcast_unlock(net);
2067 return -EMSGSIZE;
2068 }
2069
2070 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2071 if (!attrs)
2072 goto msg_full;
2073
2074 /* The broadcast link is always up */
2075 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2076 goto attr_msg_full;
2077
2078 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2079 goto attr_msg_full;
2080 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2081 goto attr_msg_full;
2082 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2083 goto attr_msg_full;
2084 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2085 goto attr_msg_full;
2086
2087 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2088 if (!prop)
2089 goto attr_msg_full;
2090 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
2091 goto prop_msg_full;
2092 nla_nest_end(msg->skb, prop);
2093
2094 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2095 if (err)
2096 goto attr_msg_full;
2097
2098 tipc_bcast_unlock(net);
2099 nla_nest_end(msg->skb, attrs);
2100 genlmsg_end(msg->skb, hdr);
2101
2102 return 0;
2103
2104prop_msg_full:
2105 nla_nest_cancel(msg->skb, prop);
2106attr_msg_full:
2107 nla_nest_cancel(msg->skb, attrs);
2108msg_full:
2109 tipc_bcast_unlock(net);
2110 genlmsg_cancel(msg->skb, hdr);
2111
2112 return -EMSGSIZE;
2113}
2114
2115void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2116 struct sk_buff_head *xmitq)
2117{
2118 l->tolerance = tol;
2119 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, tol, 0, xmitq);
2120}
2121
2122void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2123 struct sk_buff_head *xmitq)
2124{
2125 l->priority = prio;
2126 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, prio, xmitq);
2127}
2128
2129void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2130{
2131 l->abort_limit = limit;
2132}