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1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "subscr.h"
39#include "link.h"
40#include "bcast.h"
41#include "socket.h"
42#include "name_distr.h"
43#include "discover.h"
44#include "netlink.h"
45#include "monitor.h"
46#include "trace.h"
47#include "crypto.h"
48
49#include <linux/pkt_sched.h>
50
51struct tipc_stats {
52 u32 sent_pkts;
53 u32 recv_pkts;
54 u32 sent_states;
55 u32 recv_states;
56 u32 sent_probes;
57 u32 recv_probes;
58 u32 sent_nacks;
59 u32 recv_nacks;
60 u32 sent_acks;
61 u32 sent_bundled;
62 u32 sent_bundles;
63 u32 recv_bundled;
64 u32 recv_bundles;
65 u32 retransmitted;
66 u32 sent_fragmented;
67 u32 sent_fragments;
68 u32 recv_fragmented;
69 u32 recv_fragments;
70 u32 link_congs; /* # port sends blocked by congestion */
71 u32 deferred_recv;
72 u32 duplicates;
73 u32 max_queue_sz; /* send queue size high water mark */
74 u32 accu_queue_sz; /* used for send queue size profiling */
75 u32 queue_sz_counts; /* used for send queue size profiling */
76 u32 msg_length_counts; /* used for message length profiling */
77 u32 msg_lengths_total; /* used for message length profiling */
78 u32 msg_length_profile[7]; /* used for msg. length profiling */
79};
80
81/**
82 * struct tipc_link - TIPC link data structure
83 * @addr: network address of link's peer node
84 * @name: link name character string
85 * @media_addr: media address to use when sending messages over link
86 * @timer: link timer
87 * @net: pointer to namespace struct
88 * @refcnt: reference counter for permanent references (owner node & timer)
89 * @peer_session: link session # being used by peer end of link
90 * @peer_bearer_id: bearer id used by link's peer endpoint
91 * @bearer_id: local bearer id used by link
92 * @tolerance: minimum link continuity loss needed to reset link [in ms]
93 * @abort_limit: # of unacknowledged continuity probes needed to reset link
94 * @state: current state of link FSM
95 * @peer_caps: bitmap describing capabilities of peer node
96 * @silent_intv_cnt: # of timer intervals without any reception from peer
97 * @proto_msg: template for control messages generated by link
98 * @pmsg: convenience pointer to "proto_msg" field
99 * @priority: current link priority
100 * @net_plane: current link network plane ('A' through 'H')
101 * @mon_state: cookie with information needed by link monitor
102 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
103 * @exp_msg_count: # of tunnelled messages expected during link changeover
104 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
105 * @mtu: current maximum packet size for this link
106 * @advertised_mtu: advertised own mtu when link is being established
107 * @transmitq: queue for sent, non-acked messages
108 * @backlogq: queue for messages waiting to be sent
109 * @snt_nxt: next sequence number to use for outbound messages
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 */
124struct tipc_link {
125 u32 addr;
126 char name[TIPC_MAX_LINK_NAME];
127 struct net *net;
128
129 /* Management and link supervision data */
130 u16 peer_session;
131 u16 session;
132 u16 snd_nxt_state;
133 u16 rcv_nxt_state;
134 u32 peer_bearer_id;
135 u32 bearer_id;
136 u32 tolerance;
137 u32 abort_limit;
138 u32 state;
139 u16 peer_caps;
140 bool in_session;
141 bool active;
142 u32 silent_intv_cnt;
143 char if_name[TIPC_MAX_IF_NAME];
144 u32 priority;
145 char net_plane;
146 struct tipc_mon_state mon_state;
147 u16 rst_cnt;
148
149 /* Failover/synch */
150 u16 drop_point;
151 struct sk_buff *failover_reasm_skb;
152 struct sk_buff_head failover_deferdq;
153
154 /* Max packet negotiation */
155 u16 mtu;
156 u16 advertised_mtu;
157
158 /* Sending */
159 struct sk_buff_head transmq;
160 struct sk_buff_head backlogq;
161 struct {
162 u16 len;
163 u16 limit;
164 struct sk_buff *target_bskb;
165 } backlog[5];
166 u16 snd_nxt;
167
168 /* Reception */
169 u16 rcv_nxt;
170 u32 rcv_unacked;
171 struct sk_buff_head deferdq;
172 struct sk_buff_head *inputq;
173 struct sk_buff_head *namedq;
174
175 /* Congestion handling */
176 struct sk_buff_head wakeupq;
177 u16 window;
178 u16 min_win;
179 u16 ssthresh;
180 u16 max_win;
181 u16 cong_acks;
182 u16 checkpoint;
183
184 /* Fragmentation/reassembly */
185 struct sk_buff *reasm_buf;
186 struct sk_buff *reasm_tnlmsg;
187
188 /* Broadcast */
189 u16 ackers;
190 u16 acked;
191 u16 last_gap;
192 struct tipc_gap_ack_blks *last_ga;
193 struct tipc_link *bc_rcvlink;
194 struct tipc_link *bc_sndlink;
195 u8 nack_state;
196 bool bc_peer_is_up;
197
198 /* Statistics */
199 struct tipc_stats stats;
200};
201
202/*
203 * Error message prefixes
204 */
205static const char *link_co_err = "Link tunneling error, ";
206static const char *link_rst_msg = "Resetting link ";
207
208/* Send states for broadcast NACKs
209 */
210enum {
211 BC_NACK_SND_CONDITIONAL,
212 BC_NACK_SND_UNCONDITIONAL,
213 BC_NACK_SND_SUPPRESS,
214};
215
216#define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
217#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
218
219/*
220 * Interval between NACKs when packets arrive out of order
221 */
222#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
223
224/* Link FSM states:
225 */
226enum {
227 LINK_ESTABLISHED = 0xe,
228 LINK_ESTABLISHING = 0xe << 4,
229 LINK_RESET = 0x1 << 8,
230 LINK_RESETTING = 0x2 << 12,
231 LINK_PEER_RESET = 0xd << 16,
232 LINK_FAILINGOVER = 0xf << 20,
233 LINK_SYNCHING = 0xc << 24
234};
235
236/* Link FSM state checking routines
237 */
238static int link_is_up(struct tipc_link *l)
239{
240 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
241}
242
243static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
244 struct sk_buff_head *xmitq);
245static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
246 bool probe_reply, u16 rcvgap,
247 int tolerance, int priority,
248 struct sk_buff_head *xmitq);
249static void link_print(struct tipc_link *l, const char *str);
250static int tipc_link_build_nack_msg(struct tipc_link *l,
251 struct sk_buff_head *xmitq);
252static void tipc_link_build_bc_init_msg(struct tipc_link *l,
253 struct sk_buff_head *xmitq);
254static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
255 struct tipc_link *l, u8 start_index);
256static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
257static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
258 u16 acked, u16 gap,
259 struct tipc_gap_ack_blks *ga,
260 struct sk_buff_head *xmitq,
261 bool *retransmitted, int *rc);
262static void tipc_link_update_cwin(struct tipc_link *l, int released,
263 bool retransmitted);
264/*
265 * Simple non-static link routines (i.e. referenced outside this file)
266 */
267bool tipc_link_is_up(struct tipc_link *l)
268{
269 return link_is_up(l);
270}
271
272bool tipc_link_peer_is_down(struct tipc_link *l)
273{
274 return l->state == LINK_PEER_RESET;
275}
276
277bool tipc_link_is_reset(struct tipc_link *l)
278{
279 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
280}
281
282bool tipc_link_is_establishing(struct tipc_link *l)
283{
284 return l->state == LINK_ESTABLISHING;
285}
286
287bool tipc_link_is_synching(struct tipc_link *l)
288{
289 return l->state == LINK_SYNCHING;
290}
291
292bool tipc_link_is_failingover(struct tipc_link *l)
293{
294 return l->state == LINK_FAILINGOVER;
295}
296
297bool tipc_link_is_blocked(struct tipc_link *l)
298{
299 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
300}
301
302static bool link_is_bc_sndlink(struct tipc_link *l)
303{
304 return !l->bc_sndlink;
305}
306
307static bool link_is_bc_rcvlink(struct tipc_link *l)
308{
309 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
310}
311
312void tipc_link_set_active(struct tipc_link *l, bool active)
313{
314 l->active = active;
315}
316
317u32 tipc_link_id(struct tipc_link *l)
318{
319 return l->peer_bearer_id << 16 | l->bearer_id;
320}
321
322int tipc_link_min_win(struct tipc_link *l)
323{
324 return l->min_win;
325}
326
327int tipc_link_max_win(struct tipc_link *l)
328{
329 return l->max_win;
330}
331
332int tipc_link_prio(struct tipc_link *l)
333{
334 return l->priority;
335}
336
337unsigned long tipc_link_tolerance(struct tipc_link *l)
338{
339 return l->tolerance;
340}
341
342struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
343{
344 return l->inputq;
345}
346
347char tipc_link_plane(struct tipc_link *l)
348{
349 return l->net_plane;
350}
351
352void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
353{
354 l->peer_caps = capabilities;
355}
356
357void tipc_link_add_bc_peer(struct tipc_link *snd_l,
358 struct tipc_link *uc_l,
359 struct sk_buff_head *xmitq)
360{
361 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
362
363 snd_l->ackers++;
364 rcv_l->acked = snd_l->snd_nxt - 1;
365 snd_l->state = LINK_ESTABLISHED;
366 tipc_link_build_bc_init_msg(uc_l, xmitq);
367}
368
369void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
370 struct tipc_link *rcv_l,
371 struct sk_buff_head *xmitq)
372{
373 u16 ack = snd_l->snd_nxt - 1;
374
375 snd_l->ackers--;
376 rcv_l->bc_peer_is_up = true;
377 rcv_l->state = LINK_ESTABLISHED;
378 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
379 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
380 tipc_link_reset(rcv_l);
381 rcv_l->state = LINK_RESET;
382 if (!snd_l->ackers) {
383 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
384 tipc_link_reset(snd_l);
385 snd_l->state = LINK_RESET;
386 __skb_queue_purge(xmitq);
387 }
388}
389
390int tipc_link_bc_peers(struct tipc_link *l)
391{
392 return l->ackers;
393}
394
395static u16 link_bc_rcv_gap(struct tipc_link *l)
396{
397 struct sk_buff *skb = skb_peek(&l->deferdq);
398 u16 gap = 0;
399
400 if (more(l->snd_nxt, l->rcv_nxt))
401 gap = l->snd_nxt - l->rcv_nxt;
402 if (skb)
403 gap = buf_seqno(skb) - l->rcv_nxt;
404 return gap;
405}
406
407void tipc_link_set_mtu(struct tipc_link *l, int mtu)
408{
409 l->mtu = mtu;
410}
411
412int tipc_link_mtu(struct tipc_link *l)
413{
414 return l->mtu;
415}
416
417int tipc_link_mss(struct tipc_link *l)
418{
419#ifdef CONFIG_TIPC_CRYPTO
420 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
421#else
422 return l->mtu - INT_H_SIZE;
423#endif
424}
425
426u16 tipc_link_rcv_nxt(struct tipc_link *l)
427{
428 return l->rcv_nxt;
429}
430
431u16 tipc_link_acked(struct tipc_link *l)
432{
433 return l->acked;
434}
435
436char *tipc_link_name(struct tipc_link *l)
437{
438 return l->name;
439}
440
441u32 tipc_link_state(struct tipc_link *l)
442{
443 return l->state;
444}
445
446/**
447 * tipc_link_create - create a new link
448 * @net: pointer to associated network namespace
449 * @if_name: associated interface name
450 * @bearer_id: id (index) of associated bearer
451 * @tolerance: link tolerance to be used by link
452 * @net_plane: network plane (A,B,c..) this link belongs to
453 * @mtu: mtu to be advertised by link
454 * @priority: priority to be used by link
455 * @min_win: minimal send window to be used by link
456 * @max_win: maximal send window to be used by link
457 * @session: session to be used by link
458 * @ownnode: identity of own node
459 * @peer: node id of peer node
460 * @peer_caps: bitmap describing peer node capabilities
461 * @bc_sndlink: the namespace global link used for broadcast sending
462 * @bc_rcvlink: the peer specific link used for broadcast reception
463 * @inputq: queue to put messages ready for delivery
464 * @namedq: queue to put binding table update messages ready for delivery
465 * @link: return value, pointer to put the created link
466 *
467 * Returns true if link was created, otherwise false
468 */
469bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
470 int tolerance, char net_plane, u32 mtu, int priority,
471 u32 min_win, u32 max_win, u32 session, u32 self,
472 u32 peer, u8 *peer_id, u16 peer_caps,
473 struct tipc_link *bc_sndlink,
474 struct tipc_link *bc_rcvlink,
475 struct sk_buff_head *inputq,
476 struct sk_buff_head *namedq,
477 struct tipc_link **link)
478{
479 char peer_str[NODE_ID_STR_LEN] = {0,};
480 char self_str[NODE_ID_STR_LEN] = {0,};
481 struct tipc_link *l;
482
483 l = kzalloc(sizeof(*l), GFP_ATOMIC);
484 if (!l)
485 return false;
486 *link = l;
487 l->session = session;
488
489 /* Set link name for unicast links only */
490 if (peer_id) {
491 tipc_nodeid2string(self_str, tipc_own_id(net));
492 if (strlen(self_str) > 16)
493 sprintf(self_str, "%x", self);
494 tipc_nodeid2string(peer_str, peer_id);
495 if (strlen(peer_str) > 16)
496 sprintf(peer_str, "%x", peer);
497 }
498 /* Peer i/f name will be completed by reset/activate message */
499 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
500 self_str, if_name, peer_str);
501
502 strcpy(l->if_name, if_name);
503 l->addr = peer;
504 l->peer_caps = peer_caps;
505 l->net = net;
506 l->in_session = false;
507 l->bearer_id = bearer_id;
508 l->tolerance = tolerance;
509 if (bc_rcvlink)
510 bc_rcvlink->tolerance = tolerance;
511 l->net_plane = net_plane;
512 l->advertised_mtu = mtu;
513 l->mtu = mtu;
514 l->priority = priority;
515 tipc_link_set_queue_limits(l, min_win, max_win);
516 l->ackers = 1;
517 l->bc_sndlink = bc_sndlink;
518 l->bc_rcvlink = bc_rcvlink;
519 l->inputq = inputq;
520 l->namedq = namedq;
521 l->state = LINK_RESETTING;
522 __skb_queue_head_init(&l->transmq);
523 __skb_queue_head_init(&l->backlogq);
524 __skb_queue_head_init(&l->deferdq);
525 __skb_queue_head_init(&l->failover_deferdq);
526 skb_queue_head_init(&l->wakeupq);
527 skb_queue_head_init(l->inputq);
528 return true;
529}
530
531/**
532 * tipc_link_bc_create - create new link to be used for broadcast
533 * @net: pointer to associated network namespace
534 * @mtu: mtu to be used initially if no peers
535 * @min_win: minimal send window to be used by link
536 * @max_win: maximal send window to be used by link
537 * @inputq: queue to put messages ready for delivery
538 * @namedq: queue to put binding table update messages ready for delivery
539 * @link: return value, pointer to put the created link
540 *
541 * Returns true if link was created, otherwise false
542 */
543bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
544 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
545 struct sk_buff_head *inputq,
546 struct sk_buff_head *namedq,
547 struct tipc_link *bc_sndlink,
548 struct tipc_link **link)
549{
550 struct tipc_link *l;
551
552 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
553 max_win, 0, ownnode, peer, NULL, peer_caps,
554 bc_sndlink, NULL, inputq, namedq, link))
555 return false;
556
557 l = *link;
558 if (peer_id) {
559 char peer_str[NODE_ID_STR_LEN] = {0,};
560
561 tipc_nodeid2string(peer_str, peer_id);
562 if (strlen(peer_str) > 16)
563 sprintf(peer_str, "%x", peer);
564 /* Broadcast receiver link name: "broadcast-link:<peer>" */
565 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
566 peer_str);
567 } else {
568 strcpy(l->name, tipc_bclink_name);
569 }
570 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
571 tipc_link_reset(l);
572 l->state = LINK_RESET;
573 l->ackers = 0;
574 l->bc_rcvlink = l;
575
576 /* Broadcast send link is always up */
577 if (link_is_bc_sndlink(l))
578 l->state = LINK_ESTABLISHED;
579
580 /* Disable replicast if even a single peer doesn't support it */
581 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
582 tipc_bcast_toggle_rcast(net, false);
583
584 return true;
585}
586
587/**
588 * tipc_link_fsm_evt - link finite state machine
589 * @l: pointer to link
590 * @evt: state machine event to be processed
591 */
592int tipc_link_fsm_evt(struct tipc_link *l, int evt)
593{
594 int rc = 0;
595 int old_state = l->state;
596
597 switch (l->state) {
598 case LINK_RESETTING:
599 switch (evt) {
600 case LINK_PEER_RESET_EVT:
601 l->state = LINK_PEER_RESET;
602 break;
603 case LINK_RESET_EVT:
604 l->state = LINK_RESET;
605 break;
606 case LINK_FAILURE_EVT:
607 case LINK_FAILOVER_BEGIN_EVT:
608 case LINK_ESTABLISH_EVT:
609 case LINK_FAILOVER_END_EVT:
610 case LINK_SYNCH_BEGIN_EVT:
611 case LINK_SYNCH_END_EVT:
612 default:
613 goto illegal_evt;
614 }
615 break;
616 case LINK_RESET:
617 switch (evt) {
618 case LINK_PEER_RESET_EVT:
619 l->state = LINK_ESTABLISHING;
620 break;
621 case LINK_FAILOVER_BEGIN_EVT:
622 l->state = LINK_FAILINGOVER;
623 case LINK_FAILURE_EVT:
624 case LINK_RESET_EVT:
625 case LINK_ESTABLISH_EVT:
626 case LINK_FAILOVER_END_EVT:
627 break;
628 case LINK_SYNCH_BEGIN_EVT:
629 case LINK_SYNCH_END_EVT:
630 default:
631 goto illegal_evt;
632 }
633 break;
634 case LINK_PEER_RESET:
635 switch (evt) {
636 case LINK_RESET_EVT:
637 l->state = LINK_ESTABLISHING;
638 break;
639 case LINK_PEER_RESET_EVT:
640 case LINK_ESTABLISH_EVT:
641 case LINK_FAILURE_EVT:
642 break;
643 case LINK_SYNCH_BEGIN_EVT:
644 case LINK_SYNCH_END_EVT:
645 case LINK_FAILOVER_BEGIN_EVT:
646 case LINK_FAILOVER_END_EVT:
647 default:
648 goto illegal_evt;
649 }
650 break;
651 case LINK_FAILINGOVER:
652 switch (evt) {
653 case LINK_FAILOVER_END_EVT:
654 l->state = LINK_RESET;
655 break;
656 case LINK_PEER_RESET_EVT:
657 case LINK_RESET_EVT:
658 case LINK_ESTABLISH_EVT:
659 case LINK_FAILURE_EVT:
660 break;
661 case LINK_FAILOVER_BEGIN_EVT:
662 case LINK_SYNCH_BEGIN_EVT:
663 case LINK_SYNCH_END_EVT:
664 default:
665 goto illegal_evt;
666 }
667 break;
668 case LINK_ESTABLISHING:
669 switch (evt) {
670 case LINK_ESTABLISH_EVT:
671 l->state = LINK_ESTABLISHED;
672 break;
673 case LINK_FAILOVER_BEGIN_EVT:
674 l->state = LINK_FAILINGOVER;
675 break;
676 case LINK_RESET_EVT:
677 l->state = LINK_RESET;
678 break;
679 case LINK_FAILURE_EVT:
680 case LINK_PEER_RESET_EVT:
681 case LINK_SYNCH_BEGIN_EVT:
682 case LINK_FAILOVER_END_EVT:
683 break;
684 case LINK_SYNCH_END_EVT:
685 default:
686 goto illegal_evt;
687 }
688 break;
689 case LINK_ESTABLISHED:
690 switch (evt) {
691 case LINK_PEER_RESET_EVT:
692 l->state = LINK_PEER_RESET;
693 rc |= TIPC_LINK_DOWN_EVT;
694 break;
695 case LINK_FAILURE_EVT:
696 l->state = LINK_RESETTING;
697 rc |= TIPC_LINK_DOWN_EVT;
698 break;
699 case LINK_RESET_EVT:
700 l->state = LINK_RESET;
701 break;
702 case LINK_ESTABLISH_EVT:
703 case LINK_SYNCH_END_EVT:
704 break;
705 case LINK_SYNCH_BEGIN_EVT:
706 l->state = LINK_SYNCHING;
707 break;
708 case LINK_FAILOVER_BEGIN_EVT:
709 case LINK_FAILOVER_END_EVT:
710 default:
711 goto illegal_evt;
712 }
713 break;
714 case LINK_SYNCHING:
715 switch (evt) {
716 case LINK_PEER_RESET_EVT:
717 l->state = LINK_PEER_RESET;
718 rc |= TIPC_LINK_DOWN_EVT;
719 break;
720 case LINK_FAILURE_EVT:
721 l->state = LINK_RESETTING;
722 rc |= TIPC_LINK_DOWN_EVT;
723 break;
724 case LINK_RESET_EVT:
725 l->state = LINK_RESET;
726 break;
727 case LINK_ESTABLISH_EVT:
728 case LINK_SYNCH_BEGIN_EVT:
729 break;
730 case LINK_SYNCH_END_EVT:
731 l->state = LINK_ESTABLISHED;
732 break;
733 case LINK_FAILOVER_BEGIN_EVT:
734 case LINK_FAILOVER_END_EVT:
735 default:
736 goto illegal_evt;
737 }
738 break;
739 default:
740 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
741 }
742 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
743 return rc;
744illegal_evt:
745 pr_err("Illegal FSM event %x in state %x on link %s\n",
746 evt, l->state, l->name);
747 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
748 return rc;
749}
750
751/* link_profile_stats - update statistical profiling of traffic
752 */
753static void link_profile_stats(struct tipc_link *l)
754{
755 struct sk_buff *skb;
756 struct tipc_msg *msg;
757 int length;
758
759 /* Update counters used in statistical profiling of send traffic */
760 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
761 l->stats.queue_sz_counts++;
762
763 skb = skb_peek(&l->transmq);
764 if (!skb)
765 return;
766 msg = buf_msg(skb);
767 length = msg_size(msg);
768
769 if (msg_user(msg) == MSG_FRAGMENTER) {
770 if (msg_type(msg) != FIRST_FRAGMENT)
771 return;
772 length = msg_size(msg_inner_hdr(msg));
773 }
774 l->stats.msg_lengths_total += length;
775 l->stats.msg_length_counts++;
776 if (length <= 64)
777 l->stats.msg_length_profile[0]++;
778 else if (length <= 256)
779 l->stats.msg_length_profile[1]++;
780 else if (length <= 1024)
781 l->stats.msg_length_profile[2]++;
782 else if (length <= 4096)
783 l->stats.msg_length_profile[3]++;
784 else if (length <= 16384)
785 l->stats.msg_length_profile[4]++;
786 else if (length <= 32768)
787 l->stats.msg_length_profile[5]++;
788 else
789 l->stats.msg_length_profile[6]++;
790}
791
792/**
793 * tipc_link_too_silent - check if link is "too silent"
794 * @l: tipc link to be checked
795 *
796 * Returns true if the link 'silent_intv_cnt' is about to reach the
797 * 'abort_limit' value, otherwise false
798 */
799bool tipc_link_too_silent(struct tipc_link *l)
800{
801 return (l->silent_intv_cnt + 2 > l->abort_limit);
802}
803
804/* tipc_link_timeout - perform periodic task as instructed from node timeout
805 */
806int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
807{
808 int mtyp = 0;
809 int rc = 0;
810 bool state = false;
811 bool probe = false;
812 bool setup = false;
813 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
814 u16 bc_acked = l->bc_rcvlink->acked;
815 struct tipc_mon_state *mstate = &l->mon_state;
816
817 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
818 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
819 switch (l->state) {
820 case LINK_ESTABLISHED:
821 case LINK_SYNCHING:
822 mtyp = STATE_MSG;
823 link_profile_stats(l);
824 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
825 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
826 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
827 state = bc_acked != bc_snt;
828 state |= l->bc_rcvlink->rcv_unacked;
829 state |= l->rcv_unacked;
830 state |= !skb_queue_empty(&l->transmq);
831 probe = mstate->probing;
832 probe |= l->silent_intv_cnt;
833 if (probe || mstate->monitoring)
834 l->silent_intv_cnt++;
835 probe |= !skb_queue_empty(&l->deferdq);
836 if (l->snd_nxt == l->checkpoint) {
837 tipc_link_update_cwin(l, 0, 0);
838 probe = true;
839 }
840 l->checkpoint = l->snd_nxt;
841 break;
842 case LINK_RESET:
843 setup = l->rst_cnt++ <= 4;
844 setup |= !(l->rst_cnt % 16);
845 mtyp = RESET_MSG;
846 break;
847 case LINK_ESTABLISHING:
848 setup = true;
849 mtyp = ACTIVATE_MSG;
850 break;
851 case LINK_PEER_RESET:
852 case LINK_RESETTING:
853 case LINK_FAILINGOVER:
854 break;
855 default:
856 break;
857 }
858
859 if (state || probe || setup)
860 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
861
862 return rc;
863}
864
865/**
866 * link_schedule_user - schedule a message sender for wakeup after congestion
867 * @l: congested link
868 * @hdr: header of message that is being sent
869 * Create pseudo msg to send back to user when congestion abates
870 */
871static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
872{
873 u32 dnode = tipc_own_addr(l->net);
874 u32 dport = msg_origport(hdr);
875 struct sk_buff *skb;
876
877 /* Create and schedule wakeup pseudo message */
878 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
879 dnode, l->addr, dport, 0, 0);
880 if (!skb)
881 return -ENOBUFS;
882 msg_set_dest_droppable(buf_msg(skb), true);
883 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
884 skb_queue_tail(&l->wakeupq, skb);
885 l->stats.link_congs++;
886 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
887 return -ELINKCONG;
888}
889
890/**
891 * link_prepare_wakeup - prepare users for wakeup after congestion
892 * @l: congested link
893 * Wake up a number of waiting users, as permitted by available space
894 * in the send queue
895 */
896static void link_prepare_wakeup(struct tipc_link *l)
897{
898 struct sk_buff_head *wakeupq = &l->wakeupq;
899 struct sk_buff_head *inputq = l->inputq;
900 struct sk_buff *skb, *tmp;
901 struct sk_buff_head tmpq;
902 int avail[5] = {0,};
903 int imp = 0;
904
905 __skb_queue_head_init(&tmpq);
906
907 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
908 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
909
910 skb_queue_walk_safe(wakeupq, skb, tmp) {
911 imp = TIPC_SKB_CB(skb)->chain_imp;
912 if (avail[imp] <= 0)
913 continue;
914 avail[imp]--;
915 __skb_unlink(skb, wakeupq);
916 __skb_queue_tail(&tmpq, skb);
917 }
918
919 spin_lock_bh(&inputq->lock);
920 skb_queue_splice_tail(&tmpq, inputq);
921 spin_unlock_bh(&inputq->lock);
922
923}
924
925/**
926 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
927 * the given skb should be next attempted
928 * @skb: skb to set a future retransmission time for
929 * @l: link the skb will be transmitted on
930 */
931static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
932 struct tipc_link *l)
933{
934 if (link_is_bc_sndlink(l))
935 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
936 else
937 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
938}
939
940void tipc_link_reset(struct tipc_link *l)
941{
942 struct sk_buff_head list;
943 u32 imp;
944
945 __skb_queue_head_init(&list);
946
947 l->in_session = false;
948 /* Force re-synch of peer session number before establishing */
949 l->peer_session--;
950 l->session++;
951 l->mtu = l->advertised_mtu;
952
953 spin_lock_bh(&l->wakeupq.lock);
954 skb_queue_splice_init(&l->wakeupq, &list);
955 spin_unlock_bh(&l->wakeupq.lock);
956
957 spin_lock_bh(&l->inputq->lock);
958 skb_queue_splice_init(&list, l->inputq);
959 spin_unlock_bh(&l->inputq->lock);
960
961 __skb_queue_purge(&l->transmq);
962 __skb_queue_purge(&l->deferdq);
963 __skb_queue_purge(&l->backlogq);
964 __skb_queue_purge(&l->failover_deferdq);
965 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
966 l->backlog[imp].len = 0;
967 l->backlog[imp].target_bskb = NULL;
968 }
969 kfree_skb(l->reasm_buf);
970 kfree_skb(l->reasm_tnlmsg);
971 kfree_skb(l->failover_reasm_skb);
972 l->reasm_buf = NULL;
973 l->reasm_tnlmsg = NULL;
974 l->failover_reasm_skb = NULL;
975 l->rcv_unacked = 0;
976 l->snd_nxt = 1;
977 l->rcv_nxt = 1;
978 l->snd_nxt_state = 1;
979 l->rcv_nxt_state = 1;
980 l->acked = 0;
981 l->last_gap = 0;
982 kfree(l->last_ga);
983 l->last_ga = NULL;
984 l->silent_intv_cnt = 0;
985 l->rst_cnt = 0;
986 l->bc_peer_is_up = false;
987 memset(&l->mon_state, 0, sizeof(l->mon_state));
988 tipc_link_reset_stats(l);
989}
990
991/**
992 * tipc_link_xmit(): enqueue buffer list according to queue situation
993 * @l: link to use
994 * @list: chain of buffers containing message
995 * @xmitq: returned list of packets to be sent by caller
996 *
997 * Consumes the buffer chain.
998 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
999 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1000 */
1001int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1002 struct sk_buff_head *xmitq)
1003{
1004 struct tipc_msg *hdr = buf_msg(skb_peek(list));
1005 struct sk_buff_head *backlogq = &l->backlogq;
1006 struct sk_buff_head *transmq = &l->transmq;
1007 struct sk_buff *skb, *_skb;
1008 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1009 u16 ack = l->rcv_nxt - 1;
1010 u16 seqno = l->snd_nxt;
1011 int pkt_cnt = skb_queue_len(list);
1012 int imp = msg_importance(hdr);
1013 unsigned int mss = tipc_link_mss(l);
1014 unsigned int cwin = l->window;
1015 unsigned int mtu = l->mtu;
1016 bool new_bundle;
1017 int rc = 0;
1018
1019 if (unlikely(msg_size(hdr) > mtu)) {
1020 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1021 skb_queue_len(list), msg_user(hdr),
1022 msg_type(hdr), msg_size(hdr), mtu);
1023 __skb_queue_purge(list);
1024 return -EMSGSIZE;
1025 }
1026
1027 /* Allow oversubscription of one data msg per source at congestion */
1028 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1029 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1030 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1031 return -ENOBUFS;
1032 }
1033 rc = link_schedule_user(l, hdr);
1034 }
1035
1036 if (pkt_cnt > 1) {
1037 l->stats.sent_fragmented++;
1038 l->stats.sent_fragments += pkt_cnt;
1039 }
1040
1041 /* Prepare each packet for sending, and add to relevant queue: */
1042 while ((skb = __skb_dequeue(list))) {
1043 if (likely(skb_queue_len(transmq) < cwin)) {
1044 hdr = buf_msg(skb);
1045 msg_set_seqno(hdr, seqno);
1046 msg_set_ack(hdr, ack);
1047 msg_set_bcast_ack(hdr, bc_ack);
1048 _skb = skb_clone(skb, GFP_ATOMIC);
1049 if (!_skb) {
1050 kfree_skb(skb);
1051 __skb_queue_purge(list);
1052 return -ENOBUFS;
1053 }
1054 __skb_queue_tail(transmq, skb);
1055 tipc_link_set_skb_retransmit_time(skb, l);
1056 __skb_queue_tail(xmitq, _skb);
1057 TIPC_SKB_CB(skb)->ackers = l->ackers;
1058 l->rcv_unacked = 0;
1059 l->stats.sent_pkts++;
1060 seqno++;
1061 continue;
1062 }
1063 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1064 mss, l->addr, &new_bundle)) {
1065 if (skb) {
1066 /* Keep a ref. to the skb for next try */
1067 l->backlog[imp].target_bskb = skb;
1068 l->backlog[imp].len++;
1069 __skb_queue_tail(backlogq, skb);
1070 } else {
1071 if (new_bundle) {
1072 l->stats.sent_bundles++;
1073 l->stats.sent_bundled++;
1074 }
1075 l->stats.sent_bundled++;
1076 }
1077 continue;
1078 }
1079 l->backlog[imp].target_bskb = NULL;
1080 l->backlog[imp].len += (1 + skb_queue_len(list));
1081 __skb_queue_tail(backlogq, skb);
1082 skb_queue_splice_tail_init(list, backlogq);
1083 }
1084 l->snd_nxt = seqno;
1085 return rc;
1086}
1087
1088static void tipc_link_update_cwin(struct tipc_link *l, int released,
1089 bool retransmitted)
1090{
1091 int bklog_len = skb_queue_len(&l->backlogq);
1092 struct sk_buff_head *txq = &l->transmq;
1093 int txq_len = skb_queue_len(txq);
1094 u16 cwin = l->window;
1095
1096 /* Enter fast recovery */
1097 if (unlikely(retransmitted)) {
1098 l->ssthresh = max_t(u16, l->window / 2, 300);
1099 l->window = min_t(u16, l->ssthresh, l->window);
1100 return;
1101 }
1102 /* Enter slow start */
1103 if (unlikely(!released)) {
1104 l->ssthresh = max_t(u16, l->window / 2, 300);
1105 l->window = l->min_win;
1106 return;
1107 }
1108 /* Don't increase window if no pressure on the transmit queue */
1109 if (txq_len + bklog_len < cwin)
1110 return;
1111
1112 /* Don't increase window if there are holes the transmit queue */
1113 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1114 return;
1115
1116 l->cong_acks += released;
1117
1118 /* Slow start */
1119 if (cwin <= l->ssthresh) {
1120 l->window = min_t(u16, cwin + released, l->max_win);
1121 return;
1122 }
1123 /* Congestion avoidance */
1124 if (l->cong_acks < cwin)
1125 return;
1126 l->window = min_t(u16, ++cwin, l->max_win);
1127 l->cong_acks = 0;
1128}
1129
1130static void tipc_link_advance_backlog(struct tipc_link *l,
1131 struct sk_buff_head *xmitq)
1132{
1133 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1134 struct sk_buff_head *txq = &l->transmq;
1135 struct sk_buff *skb, *_skb;
1136 u16 ack = l->rcv_nxt - 1;
1137 u16 seqno = l->snd_nxt;
1138 struct tipc_msg *hdr;
1139 u16 cwin = l->window;
1140 u32 imp;
1141
1142 while (skb_queue_len(txq) < cwin) {
1143 skb = skb_peek(&l->backlogq);
1144 if (!skb)
1145 break;
1146 _skb = skb_clone(skb, GFP_ATOMIC);
1147 if (!_skb)
1148 break;
1149 __skb_dequeue(&l->backlogq);
1150 hdr = buf_msg(skb);
1151 imp = msg_importance(hdr);
1152 l->backlog[imp].len--;
1153 if (unlikely(skb == l->backlog[imp].target_bskb))
1154 l->backlog[imp].target_bskb = NULL;
1155 __skb_queue_tail(&l->transmq, skb);
1156 tipc_link_set_skb_retransmit_time(skb, l);
1157
1158 __skb_queue_tail(xmitq, _skb);
1159 TIPC_SKB_CB(skb)->ackers = l->ackers;
1160 msg_set_seqno(hdr, seqno);
1161 msg_set_ack(hdr, ack);
1162 msg_set_bcast_ack(hdr, bc_ack);
1163 l->rcv_unacked = 0;
1164 l->stats.sent_pkts++;
1165 seqno++;
1166 }
1167 l->snd_nxt = seqno;
1168}
1169
1170/**
1171 * link_retransmit_failure() - Detect repeated retransmit failures
1172 * @l: tipc link sender
1173 * @r: tipc link receiver (= l in case of unicast)
1174 * @rc: returned code
1175 *
1176 * Return: true if the repeated retransmit failures happens, otherwise
1177 * false
1178 */
1179static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1180 int *rc)
1181{
1182 struct sk_buff *skb = skb_peek(&l->transmq);
1183 struct tipc_msg *hdr;
1184
1185 if (!skb)
1186 return false;
1187
1188 if (!TIPC_SKB_CB(skb)->retr_cnt)
1189 return false;
1190
1191 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1192 msecs_to_jiffies(r->tolerance * 10)))
1193 return false;
1194
1195 hdr = buf_msg(skb);
1196 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1197 return false;
1198
1199 pr_warn("Retransmission failure on link <%s>\n", l->name);
1200 link_print(l, "State of link ");
1201 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1202 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1203 pr_info("sqno %u, prev: %x, dest: %x\n",
1204 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1205 pr_info("retr_stamp %d, retr_cnt %d\n",
1206 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1207 TIPC_SKB_CB(skb)->retr_cnt);
1208
1209 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1210 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1211 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1212
1213 if (link_is_bc_sndlink(l)) {
1214 r->state = LINK_RESET;
1215 *rc |= TIPC_LINK_DOWN_EVT;
1216 } else {
1217 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1218 }
1219
1220 return true;
1221}
1222
1223/* tipc_data_input - deliver data and name distr msgs to upper layer
1224 *
1225 * Consumes buffer if message is of right type
1226 * Node lock must be held
1227 */
1228static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1229 struct sk_buff_head *inputq)
1230{
1231 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1232 struct tipc_msg *hdr = buf_msg(skb);
1233
1234 switch (msg_user(hdr)) {
1235 case TIPC_LOW_IMPORTANCE:
1236 case TIPC_MEDIUM_IMPORTANCE:
1237 case TIPC_HIGH_IMPORTANCE:
1238 case TIPC_CRITICAL_IMPORTANCE:
1239 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1240 skb_queue_tail(mc_inputq, skb);
1241 return true;
1242 }
1243 fallthrough;
1244 case CONN_MANAGER:
1245 skb_queue_tail(inputq, skb);
1246 return true;
1247 case GROUP_PROTOCOL:
1248 skb_queue_tail(mc_inputq, skb);
1249 return true;
1250 case NAME_DISTRIBUTOR:
1251 l->bc_rcvlink->state = LINK_ESTABLISHED;
1252 skb_queue_tail(l->namedq, skb);
1253 return true;
1254 case MSG_BUNDLER:
1255 case TUNNEL_PROTOCOL:
1256 case MSG_FRAGMENTER:
1257 case BCAST_PROTOCOL:
1258 return false;
1259 default:
1260 pr_warn("Dropping received illegal msg type\n");
1261 kfree_skb(skb);
1262 return true;
1263 };
1264}
1265
1266/* tipc_link_input - process packet that has passed link protocol check
1267 *
1268 * Consumes buffer
1269 */
1270static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1271 struct sk_buff_head *inputq,
1272 struct sk_buff **reasm_skb)
1273{
1274 struct tipc_msg *hdr = buf_msg(skb);
1275 struct sk_buff *iskb;
1276 struct sk_buff_head tmpq;
1277 int usr = msg_user(hdr);
1278 int pos = 0;
1279
1280 if (usr == MSG_BUNDLER) {
1281 skb_queue_head_init(&tmpq);
1282 l->stats.recv_bundles++;
1283 l->stats.recv_bundled += msg_msgcnt(hdr);
1284 while (tipc_msg_extract(skb, &iskb, &pos))
1285 tipc_data_input(l, iskb, &tmpq);
1286 tipc_skb_queue_splice_tail(&tmpq, inputq);
1287 return 0;
1288 } else if (usr == MSG_FRAGMENTER) {
1289 l->stats.recv_fragments++;
1290 if (tipc_buf_append(reasm_skb, &skb)) {
1291 l->stats.recv_fragmented++;
1292 tipc_data_input(l, skb, inputq);
1293 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1294 pr_warn_ratelimited("Unable to build fragment list\n");
1295 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1296 }
1297 return 0;
1298 } else if (usr == BCAST_PROTOCOL) {
1299 tipc_bcast_lock(l->net);
1300 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1301 tipc_bcast_unlock(l->net);
1302 }
1303
1304 kfree_skb(skb);
1305 return 0;
1306}
1307
1308/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1309 * inner message along with the ones in the old link's
1310 * deferdq
1311 * @l: tunnel link
1312 * @skb: TUNNEL_PROTOCOL message
1313 * @inputq: queue to put messages ready for delivery
1314 */
1315static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1316 struct sk_buff_head *inputq)
1317{
1318 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1319 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1320 struct sk_buff_head *fdefq = &l->failover_deferdq;
1321 struct tipc_msg *hdr = buf_msg(skb);
1322 struct sk_buff *iskb;
1323 int ipos = 0;
1324 int rc = 0;
1325 u16 seqno;
1326
1327 if (msg_type(hdr) == SYNCH_MSG) {
1328 kfree_skb(skb);
1329 return 0;
1330 }
1331
1332 /* Not a fragment? */
1333 if (likely(!msg_nof_fragms(hdr))) {
1334 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1335 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1336 skb_queue_len(fdefq));
1337 return 0;
1338 }
1339 kfree_skb(skb);
1340 } else {
1341 /* Set fragment type for buf_append */
1342 if (msg_fragm_no(hdr) == 1)
1343 msg_set_type(hdr, FIRST_FRAGMENT);
1344 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1345 msg_set_type(hdr, FRAGMENT);
1346 else
1347 msg_set_type(hdr, LAST_FRAGMENT);
1348
1349 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1350 /* Successful but non-complete reassembly? */
1351 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1352 return 0;
1353 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1354 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1355 }
1356 iskb = skb;
1357 }
1358
1359 do {
1360 seqno = buf_seqno(iskb);
1361 if (unlikely(less(seqno, l->drop_point))) {
1362 kfree_skb(iskb);
1363 continue;
1364 }
1365 if (unlikely(seqno != l->drop_point)) {
1366 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1367 continue;
1368 }
1369
1370 l->drop_point++;
1371 if (!tipc_data_input(l, iskb, inputq))
1372 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1373 if (unlikely(rc))
1374 break;
1375 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1376
1377 return rc;
1378}
1379
1380/**
1381 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1382 * @ga: returned pointer to the Gap ACK blocks if any
1383 * @l: the tipc link
1384 * @hdr: the PROTOCOL/STATE_MSG header
1385 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1386 *
1387 * Return: the total Gap ACK blocks size
1388 */
1389u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1390 struct tipc_msg *hdr, bool uc)
1391{
1392 struct tipc_gap_ack_blks *p;
1393 u16 sz = 0;
1394
1395 /* Does peer support the Gap ACK blocks feature? */
1396 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1397 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1398 sz = ntohs(p->len);
1399 /* Sanity check */
1400 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1401 /* Good, check if the desired type exists */
1402 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1403 goto ok;
1404 /* Backward compatible: peer might not support bc, but uc? */
1405 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1406 if (p->ugack_cnt) {
1407 p->bgack_cnt = 0;
1408 goto ok;
1409 }
1410 }
1411 }
1412 /* Other cases: ignore! */
1413 p = NULL;
1414
1415ok:
1416 *ga = p;
1417 return sz;
1418}
1419
1420static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1421 struct tipc_link *l, u8 start_index)
1422{
1423 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1424 struct sk_buff *skb = skb_peek(&l->deferdq);
1425 u16 expect, seqno = 0;
1426 u8 n = 0;
1427
1428 if (!skb)
1429 return 0;
1430
1431 expect = buf_seqno(skb);
1432 skb_queue_walk(&l->deferdq, skb) {
1433 seqno = buf_seqno(skb);
1434 if (unlikely(more(seqno, expect))) {
1435 gacks[n].ack = htons(expect - 1);
1436 gacks[n].gap = htons(seqno - expect);
1437 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1438 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1439 l->name, n,
1440 skb_queue_len(&l->deferdq));
1441 return n;
1442 }
1443 } else if (unlikely(less(seqno, expect))) {
1444 pr_warn("Unexpected skb in deferdq!\n");
1445 continue;
1446 }
1447 expect = seqno + 1;
1448 }
1449
1450 /* last block */
1451 gacks[n].ack = htons(seqno);
1452 gacks[n].gap = 0;
1453 n++;
1454 return n;
1455}
1456
1457/* tipc_build_gap_ack_blks - build Gap ACK blocks
1458 * @l: tipc unicast link
1459 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1460 *
1461 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1462 * links of a certain peer, the buffer after built has the network data format
1463 * as found at the struct tipc_gap_ack_blks definition.
1464 *
1465 * returns the actual allocated memory size
1466 */
1467static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1468{
1469 struct tipc_link *bcl = l->bc_rcvlink;
1470 struct tipc_gap_ack_blks *ga;
1471 u16 len;
1472
1473 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1474
1475 /* Start with broadcast link first */
1476 tipc_bcast_lock(bcl->net);
1477 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1478 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1479 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1480 tipc_bcast_unlock(bcl->net);
1481
1482 /* Now for unicast link, but an explicit NACK only (???) */
1483 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1484 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1485
1486 /* Total len */
1487 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1488 ga->len = htons(len);
1489 return len;
1490}
1491
1492/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1493 * acked packets, also doing retransmissions if
1494 * gaps found
1495 * @l: tipc link with transmq queue to be advanced
1496 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1497 * @acked: seqno of last packet acked by peer without any gaps before
1498 * @gap: # of gap packets
1499 * @ga: buffer pointer to Gap ACK blocks from peer
1500 * @xmitq: queue for accumulating the retransmitted packets if any
1501 * @retransmitted: returned boolean value if a retransmission is really issued
1502 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1503 * happens (- unlikely case)
1504 *
1505 * Return: the number of packets released from the link transmq
1506 */
1507static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1508 u16 acked, u16 gap,
1509 struct tipc_gap_ack_blks *ga,
1510 struct sk_buff_head *xmitq,
1511 bool *retransmitted, int *rc)
1512{
1513 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1514 struct tipc_gap_ack *gacks = NULL;
1515 struct sk_buff *skb, *_skb, *tmp;
1516 struct tipc_msg *hdr;
1517 u32 qlen = skb_queue_len(&l->transmq);
1518 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1519 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1520 u16 ack = l->rcv_nxt - 1;
1521 u16 seqno, n = 0;
1522 u16 end = r->acked, start = end, offset = r->last_gap;
1523 u16 si = (last_ga) ? last_ga->start_index : 0;
1524 bool is_uc = !link_is_bc_sndlink(l);
1525 bool bc_has_acked = false;
1526
1527 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1528
1529 /* Determine Gap ACK blocks if any for the particular link */
1530 if (ga && is_uc) {
1531 /* Get the Gap ACKs, uc part */
1532 gack_cnt = ga->ugack_cnt;
1533 gacks = &ga->gacks[ga->bgack_cnt];
1534 } else if (ga) {
1535 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1536 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1537 GFP_ATOMIC);
1538 if (likely(this_ga)) {
1539 this_ga->start_index = 0;
1540 /* Start with the bc Gap ACKs */
1541 gack_cnt = this_ga->bgack_cnt;
1542 gacks = &this_ga->gacks[0];
1543 } else {
1544 /* Hmm, we can get in trouble..., simply ignore it */
1545 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1546 }
1547 }
1548
1549 /* Advance the link transmq */
1550 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1551 seqno = buf_seqno(skb);
1552
1553next_gap_ack:
1554 if (less_eq(seqno, nacked)) {
1555 if (is_uc)
1556 goto release;
1557 /* Skip packets peer has already acked */
1558 if (!more(seqno, r->acked))
1559 continue;
1560 /* Get the next of last Gap ACK blocks */
1561 while (more(seqno, end)) {
1562 if (!last_ga || si >= last_ga->bgack_cnt)
1563 break;
1564 start = end + offset + 1;
1565 end = ntohs(last_ga->gacks[si].ack);
1566 offset = ntohs(last_ga->gacks[si].gap);
1567 si++;
1568 WARN_ONCE(more(start, end) ||
1569 (!offset &&
1570 si < last_ga->bgack_cnt) ||
1571 si > MAX_GAP_ACK_BLKS,
1572 "Corrupted Gap ACK: %d %d %d %d %d\n",
1573 start, end, offset, si,
1574 last_ga->bgack_cnt);
1575 }
1576 /* Check against the last Gap ACK block */
1577 if (in_range(seqno, start, end))
1578 continue;
1579 /* Update/release the packet peer is acking */
1580 bc_has_acked = true;
1581 if (--TIPC_SKB_CB(skb)->ackers)
1582 continue;
1583release:
1584 /* release skb */
1585 __skb_unlink(skb, &l->transmq);
1586 kfree_skb(skb);
1587 } else if (less_eq(seqno, nacked + ngap)) {
1588 /* First gap: check if repeated retrans failures? */
1589 if (unlikely(seqno == acked + 1 &&
1590 link_retransmit_failure(l, r, rc))) {
1591 /* Ignore this bc Gap ACKs if any */
1592 kfree(this_ga);
1593 this_ga = NULL;
1594 break;
1595 }
1596 /* retransmit skb if unrestricted*/
1597 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1598 continue;
1599 tipc_link_set_skb_retransmit_time(skb, l);
1600 _skb = pskb_copy(skb, GFP_ATOMIC);
1601 if (!_skb)
1602 continue;
1603 hdr = buf_msg(_skb);
1604 msg_set_ack(hdr, ack);
1605 msg_set_bcast_ack(hdr, bc_ack);
1606 _skb->priority = TC_PRIO_CONTROL;
1607 __skb_queue_tail(xmitq, _skb);
1608 l->stats.retransmitted++;
1609 if (!is_uc)
1610 r->stats.retransmitted++;
1611 *retransmitted = true;
1612 /* Increase actual retrans counter & mark first time */
1613 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1614 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1615 } else {
1616 /* retry with Gap ACK blocks if any */
1617 if (n >= gack_cnt)
1618 break;
1619 nacked = ntohs(gacks[n].ack);
1620 ngap = ntohs(gacks[n].gap);
1621 n++;
1622 goto next_gap_ack;
1623 }
1624 }
1625
1626 /* Renew last Gap ACK blocks for bc if needed */
1627 if (bc_has_acked) {
1628 if (this_ga) {
1629 kfree(last_ga);
1630 r->last_ga = this_ga;
1631 r->last_gap = gap;
1632 } else if (last_ga) {
1633 if (less(acked, start)) {
1634 si--;
1635 offset = start - acked - 1;
1636 } else if (less(acked, end)) {
1637 acked = end;
1638 }
1639 if (si < last_ga->bgack_cnt) {
1640 last_ga->start_index = si;
1641 r->last_gap = offset;
1642 } else {
1643 kfree(last_ga);
1644 r->last_ga = NULL;
1645 r->last_gap = 0;
1646 }
1647 } else {
1648 r->last_gap = 0;
1649 }
1650 r->acked = acked;
1651 } else {
1652 kfree(this_ga);
1653 }
1654
1655 return qlen - skb_queue_len(&l->transmq);
1656}
1657
1658/* tipc_link_build_state_msg: prepare link state message for transmission
1659 *
1660 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1661 * risk of ack storms towards the sender
1662 */
1663int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1664{
1665 if (!l)
1666 return 0;
1667
1668 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1669 if (link_is_bc_rcvlink(l)) {
1670 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1671 return 0;
1672 l->rcv_unacked = 0;
1673
1674 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1675 l->snd_nxt = l->rcv_nxt;
1676 return TIPC_LINK_SND_STATE;
1677 }
1678 /* Unicast ACK */
1679 l->rcv_unacked = 0;
1680 l->stats.sent_acks++;
1681 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1682 return 0;
1683}
1684
1685/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1686 */
1687void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1688{
1689 int mtyp = RESET_MSG;
1690 struct sk_buff *skb;
1691
1692 if (l->state == LINK_ESTABLISHING)
1693 mtyp = ACTIVATE_MSG;
1694
1695 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1696
1697 /* Inform peer that this endpoint is going down if applicable */
1698 skb = skb_peek_tail(xmitq);
1699 if (skb && (l->state == LINK_RESET))
1700 msg_set_peer_stopping(buf_msg(skb), 1);
1701}
1702
1703/* tipc_link_build_nack_msg: prepare link nack message for transmission
1704 * Note that sending of broadcast NACK is coordinated among nodes, to
1705 * reduce the risk of NACK storms towards the sender
1706 */
1707static int tipc_link_build_nack_msg(struct tipc_link *l,
1708 struct sk_buff_head *xmitq)
1709{
1710 u32 def_cnt = ++l->stats.deferred_recv;
1711 struct sk_buff_head *dfq = &l->deferdq;
1712 u32 defq_len = skb_queue_len(dfq);
1713 int match1, match2;
1714
1715 if (link_is_bc_rcvlink(l)) {
1716 match1 = def_cnt & 0xf;
1717 match2 = tipc_own_addr(l->net) & 0xf;
1718 if (match1 == match2)
1719 return TIPC_LINK_SND_STATE;
1720 return 0;
1721 }
1722
1723 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1724 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1725
1726 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1727 rcvgap, 0, 0, xmitq);
1728 }
1729 return 0;
1730}
1731
1732/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1733 * @l: the link that should handle the message
1734 * @skb: TIPC packet
1735 * @xmitq: queue to place packets to be sent after this call
1736 */
1737int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1738 struct sk_buff_head *xmitq)
1739{
1740 struct sk_buff_head *defq = &l->deferdq;
1741 struct tipc_msg *hdr = buf_msg(skb);
1742 u16 seqno, rcv_nxt, win_lim;
1743 int released = 0;
1744 int rc = 0;
1745
1746 /* Verify and update link state */
1747 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1748 return tipc_link_proto_rcv(l, skb, xmitq);
1749
1750 /* Don't send probe at next timeout expiration */
1751 l->silent_intv_cnt = 0;
1752
1753 do {
1754 hdr = buf_msg(skb);
1755 seqno = msg_seqno(hdr);
1756 rcv_nxt = l->rcv_nxt;
1757 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1758
1759 if (unlikely(!link_is_up(l))) {
1760 if (l->state == LINK_ESTABLISHING)
1761 rc = TIPC_LINK_UP_EVT;
1762 kfree_skb(skb);
1763 break;
1764 }
1765
1766 /* Drop if outside receive window */
1767 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1768 l->stats.duplicates++;
1769 kfree_skb(skb);
1770 break;
1771 }
1772 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1773 NULL, NULL, NULL, NULL);
1774
1775 /* Defer delivery if sequence gap */
1776 if (unlikely(seqno != rcv_nxt)) {
1777 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1778 l->stats.duplicates++;
1779 rc |= tipc_link_build_nack_msg(l, xmitq);
1780 break;
1781 }
1782
1783 /* Deliver packet */
1784 l->rcv_nxt++;
1785 l->stats.recv_pkts++;
1786
1787 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1788 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1789 else if (!tipc_data_input(l, skb, l->inputq))
1790 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1791 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1792 rc |= tipc_link_build_state_msg(l, xmitq);
1793 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1794 break;
1795 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1796
1797 /* Forward queues and wake up waiting users */
1798 if (released) {
1799 tipc_link_update_cwin(l, released, 0);
1800 tipc_link_advance_backlog(l, xmitq);
1801 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1802 link_prepare_wakeup(l);
1803 }
1804 return rc;
1805}
1806
1807static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1808 bool probe_reply, u16 rcvgap,
1809 int tolerance, int priority,
1810 struct sk_buff_head *xmitq)
1811{
1812 struct tipc_mon_state *mstate = &l->mon_state;
1813 struct sk_buff_head *dfq = &l->deferdq;
1814 struct tipc_link *bcl = l->bc_rcvlink;
1815 struct tipc_msg *hdr;
1816 struct sk_buff *skb;
1817 bool node_up = link_is_up(bcl);
1818 u16 glen = 0, bc_rcvgap = 0;
1819 int dlen = 0;
1820 void *data;
1821
1822 /* Don't send protocol message during reset or link failover */
1823 if (tipc_link_is_blocked(l))
1824 return;
1825
1826 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1827 return;
1828
1829 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1830 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1831
1832 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1833 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1834 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1835 if (!skb)
1836 return;
1837
1838 hdr = buf_msg(skb);
1839 data = msg_data(hdr);
1840 msg_set_session(hdr, l->session);
1841 msg_set_bearer_id(hdr, l->bearer_id);
1842 msg_set_net_plane(hdr, l->net_plane);
1843 msg_set_next_sent(hdr, l->snd_nxt);
1844 msg_set_ack(hdr, l->rcv_nxt - 1);
1845 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1846 msg_set_bc_ack_invalid(hdr, !node_up);
1847 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1848 msg_set_link_tolerance(hdr, tolerance);
1849 msg_set_linkprio(hdr, priority);
1850 msg_set_redundant_link(hdr, node_up);
1851 msg_set_seq_gap(hdr, 0);
1852 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1853
1854 if (mtyp == STATE_MSG) {
1855 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1856 msg_set_seqno(hdr, l->snd_nxt_state++);
1857 msg_set_seq_gap(hdr, rcvgap);
1858 bc_rcvgap = link_bc_rcv_gap(bcl);
1859 msg_set_bc_gap(hdr, bc_rcvgap);
1860 msg_set_probe(hdr, probe);
1861 msg_set_is_keepalive(hdr, probe || probe_reply);
1862 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1863 glen = tipc_build_gap_ack_blks(l, hdr);
1864 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1865 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1866 skb_trim(skb, INT_H_SIZE + glen + dlen);
1867 l->stats.sent_states++;
1868 l->rcv_unacked = 0;
1869 } else {
1870 /* RESET_MSG or ACTIVATE_MSG */
1871 if (mtyp == ACTIVATE_MSG) {
1872 msg_set_dest_session_valid(hdr, 1);
1873 msg_set_dest_session(hdr, l->peer_session);
1874 }
1875 msg_set_max_pkt(hdr, l->advertised_mtu);
1876 strcpy(data, l->if_name);
1877 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1878 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1879 }
1880 if (probe)
1881 l->stats.sent_probes++;
1882 if (rcvgap)
1883 l->stats.sent_nacks++;
1884 if (bc_rcvgap)
1885 bcl->stats.sent_nacks++;
1886 skb->priority = TC_PRIO_CONTROL;
1887 __skb_queue_tail(xmitq, skb);
1888 trace_tipc_proto_build(skb, false, l->name);
1889}
1890
1891void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1892 struct sk_buff_head *xmitq)
1893{
1894 u32 onode = tipc_own_addr(l->net);
1895 struct tipc_msg *hdr, *ihdr;
1896 struct sk_buff_head tnlq;
1897 struct sk_buff *skb;
1898 u32 dnode = l->addr;
1899
1900 __skb_queue_head_init(&tnlq);
1901 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1902 INT_H_SIZE, BASIC_H_SIZE,
1903 dnode, onode, 0, 0, 0);
1904 if (!skb) {
1905 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1906 return;
1907 }
1908
1909 hdr = buf_msg(skb);
1910 msg_set_msgcnt(hdr, 1);
1911 msg_set_bearer_id(hdr, l->peer_bearer_id);
1912
1913 ihdr = (struct tipc_msg *)msg_data(hdr);
1914 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1915 BASIC_H_SIZE, dnode);
1916 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1917 __skb_queue_tail(&tnlq, skb);
1918 tipc_link_xmit(l, &tnlq, xmitq);
1919}
1920
1921/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1922 * with contents of the link's transmit and backlog queues.
1923 */
1924void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1925 int mtyp, struct sk_buff_head *xmitq)
1926{
1927 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1928 struct sk_buff *skb, *tnlskb;
1929 struct tipc_msg *hdr, tnlhdr;
1930 struct sk_buff_head *queue = &l->transmq;
1931 struct sk_buff_head tmpxq, tnlq, frags;
1932 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1933 bool pktcnt_need_update = false;
1934 u16 syncpt;
1935 int rc;
1936
1937 if (!tnl)
1938 return;
1939
1940 __skb_queue_head_init(&tnlq);
1941 /* Link Synching:
1942 * From now on, send only one single ("dummy") SYNCH message
1943 * to peer. The SYNCH message does not contain any data, just
1944 * a header conveying the synch point to the peer.
1945 */
1946 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1947 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1948 INT_H_SIZE, 0, l->addr,
1949 tipc_own_addr(l->net),
1950 0, 0, 0);
1951 if (!tnlskb) {
1952 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1953 link_co_err);
1954 return;
1955 }
1956
1957 hdr = buf_msg(tnlskb);
1958 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1959 msg_set_syncpt(hdr, syncpt);
1960 msg_set_bearer_id(hdr, l->peer_bearer_id);
1961 __skb_queue_tail(&tnlq, tnlskb);
1962 tipc_link_xmit(tnl, &tnlq, xmitq);
1963 return;
1964 }
1965
1966 __skb_queue_head_init(&tmpxq);
1967 __skb_queue_head_init(&frags);
1968 /* At least one packet required for safe algorithm => add dummy */
1969 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1970 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1971 0, 0, TIPC_ERR_NO_PORT);
1972 if (!skb) {
1973 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1974 return;
1975 }
1976 __skb_queue_tail(&tnlq, skb);
1977 tipc_link_xmit(l, &tnlq, &tmpxq);
1978 __skb_queue_purge(&tmpxq);
1979
1980 /* Initialize reusable tunnel packet header */
1981 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1982 mtyp, INT_H_SIZE, l->addr);
1983 if (mtyp == SYNCH_MSG)
1984 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
1985 else
1986 pktcnt = skb_queue_len(&l->transmq);
1987 pktcnt += skb_queue_len(&l->backlogq);
1988 msg_set_msgcnt(&tnlhdr, pktcnt);
1989 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1990tnl:
1991 /* Wrap each packet into a tunnel packet */
1992 skb_queue_walk(queue, skb) {
1993 hdr = buf_msg(skb);
1994 if (queue == &l->backlogq)
1995 msg_set_seqno(hdr, seqno++);
1996 pktlen = msg_size(hdr);
1997
1998 /* Tunnel link MTU is not large enough? This could be
1999 * due to:
2000 * 1) Link MTU has just changed or set differently;
2001 * 2) Or FAILOVER on the top of a SYNCH message
2002 *
2003 * The 2nd case should not happen if peer supports
2004 * TIPC_TUNNEL_ENHANCED
2005 */
2006 if (pktlen > tnl->mtu - INT_H_SIZE) {
2007 if (mtyp == FAILOVER_MSG &&
2008 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2009 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2010 &frags);
2011 if (rc) {
2012 pr_warn("%sunable to frag msg: rc %d\n",
2013 link_co_err, rc);
2014 return;
2015 }
2016 pktcnt += skb_queue_len(&frags) - 1;
2017 pktcnt_need_update = true;
2018 skb_queue_splice_tail_init(&frags, &tnlq);
2019 continue;
2020 }
2021 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2022 * => Just warn it and return!
2023 */
2024 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2025 link_co_err, msg_user(hdr),
2026 msg_type(hdr), msg_size(hdr));
2027 return;
2028 }
2029
2030 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2031 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2032 if (!tnlskb) {
2033 pr_warn("%sunable to send packet\n", link_co_err);
2034 return;
2035 }
2036 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2037 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2038 __skb_queue_tail(&tnlq, tnlskb);
2039 }
2040 if (queue != &l->backlogq) {
2041 queue = &l->backlogq;
2042 goto tnl;
2043 }
2044
2045 if (pktcnt_need_update)
2046 skb_queue_walk(&tnlq, skb) {
2047 hdr = buf_msg(skb);
2048 msg_set_msgcnt(hdr, pktcnt);
2049 }
2050
2051 tipc_link_xmit(tnl, &tnlq, xmitq);
2052
2053 if (mtyp == FAILOVER_MSG) {
2054 tnl->drop_point = l->rcv_nxt;
2055 tnl->failover_reasm_skb = l->reasm_buf;
2056 l->reasm_buf = NULL;
2057
2058 /* Failover the link's deferdq */
2059 if (unlikely(!skb_queue_empty(fdefq))) {
2060 pr_warn("Link failover deferdq not empty: %d!\n",
2061 skb_queue_len(fdefq));
2062 __skb_queue_purge(fdefq);
2063 }
2064 skb_queue_splice_init(&l->deferdq, fdefq);
2065 }
2066}
2067
2068/**
2069 * tipc_link_failover_prepare() - prepare tnl for link failover
2070 *
2071 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2072 * see the tipc_node_link_failover() for details
2073 *
2074 * @l: failover link
2075 * @tnl: tunnel link
2076 * @xmitq: queue for messages to be xmited
2077 */
2078void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2079 struct sk_buff_head *xmitq)
2080{
2081 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2082
2083 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2084
2085 /* This failover link endpoint was never established before,
2086 * so it has not received anything from peer.
2087 * Otherwise, it must be a normal failover situation or the
2088 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2089 * would have to start over from scratch instead.
2090 */
2091 tnl->drop_point = 1;
2092 tnl->failover_reasm_skb = NULL;
2093
2094 /* Initiate the link's failover deferdq */
2095 if (unlikely(!skb_queue_empty(fdefq))) {
2096 pr_warn("Link failover deferdq not empty: %d!\n",
2097 skb_queue_len(fdefq));
2098 __skb_queue_purge(fdefq);
2099 }
2100}
2101
2102/* tipc_link_validate_msg(): validate message against current link state
2103 * Returns true if message should be accepted, otherwise false
2104 */
2105bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2106{
2107 u16 curr_session = l->peer_session;
2108 u16 session = msg_session(hdr);
2109 int mtyp = msg_type(hdr);
2110
2111 if (msg_user(hdr) != LINK_PROTOCOL)
2112 return true;
2113
2114 switch (mtyp) {
2115 case RESET_MSG:
2116 if (!l->in_session)
2117 return true;
2118 /* Accept only RESET with new session number */
2119 return more(session, curr_session);
2120 case ACTIVATE_MSG:
2121 if (!l->in_session)
2122 return true;
2123 /* Accept only ACTIVATE with new or current session number */
2124 return !less(session, curr_session);
2125 case STATE_MSG:
2126 /* Accept only STATE with current session number */
2127 if (!l->in_session)
2128 return false;
2129 if (session != curr_session)
2130 return false;
2131 /* Extra sanity check */
2132 if (!link_is_up(l) && msg_ack(hdr))
2133 return false;
2134 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2135 return true;
2136 /* Accept only STATE with new sequence number */
2137 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2138 default:
2139 return false;
2140 }
2141}
2142
2143/* tipc_link_proto_rcv(): receive link level protocol message :
2144 * Note that network plane id propagates through the network, and may
2145 * change at any time. The node with lowest numerical id determines
2146 * network plane
2147 */
2148static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2149 struct sk_buff_head *xmitq)
2150{
2151 struct tipc_msg *hdr = buf_msg(skb);
2152 struct tipc_gap_ack_blks *ga = NULL;
2153 bool reply = msg_probe(hdr), retransmitted = false;
2154 u16 dlen = msg_data_sz(hdr), glen = 0;
2155 u16 peers_snd_nxt = msg_next_sent(hdr);
2156 u16 peers_tol = msg_link_tolerance(hdr);
2157 u16 peers_prio = msg_linkprio(hdr);
2158 u16 gap = msg_seq_gap(hdr);
2159 u16 ack = msg_ack(hdr);
2160 u16 rcv_nxt = l->rcv_nxt;
2161 u16 rcvgap = 0;
2162 int mtyp = msg_type(hdr);
2163 int rc = 0, released;
2164 char *if_name;
2165 void *data;
2166
2167 trace_tipc_proto_rcv(skb, false, l->name);
2168 if (tipc_link_is_blocked(l) || !xmitq)
2169 goto exit;
2170
2171 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2172 l->net_plane = msg_net_plane(hdr);
2173
2174 skb_linearize(skb);
2175 hdr = buf_msg(skb);
2176 data = msg_data(hdr);
2177
2178 if (!tipc_link_validate_msg(l, hdr)) {
2179 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2180 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2181 goto exit;
2182 }
2183
2184 switch (mtyp) {
2185 case RESET_MSG:
2186 case ACTIVATE_MSG:
2187 /* Complete own link name with peer's interface name */
2188 if_name = strrchr(l->name, ':') + 1;
2189 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2190 break;
2191 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2192 break;
2193 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2194
2195 /* Update own tolerance if peer indicates a non-zero value */
2196 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2197 l->tolerance = peers_tol;
2198 l->bc_rcvlink->tolerance = peers_tol;
2199 }
2200 /* Update own priority if peer's priority is higher */
2201 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2202 l->priority = peers_prio;
2203
2204 /* If peer is going down we want full re-establish cycle */
2205 if (msg_peer_stopping(hdr)) {
2206 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2207 break;
2208 }
2209
2210 /* If this endpoint was re-created while peer was ESTABLISHING
2211 * it doesn't know current session number. Force re-synch.
2212 */
2213 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2214 l->session != msg_dest_session(hdr)) {
2215 if (less(l->session, msg_dest_session(hdr)))
2216 l->session = msg_dest_session(hdr) + 1;
2217 break;
2218 }
2219
2220 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2221 if (mtyp == RESET_MSG || !link_is_up(l))
2222 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2223
2224 /* ACTIVATE_MSG takes up link if it was already locally reset */
2225 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2226 rc = TIPC_LINK_UP_EVT;
2227
2228 l->peer_session = msg_session(hdr);
2229 l->in_session = true;
2230 l->peer_bearer_id = msg_bearer_id(hdr);
2231 if (l->mtu > msg_max_pkt(hdr))
2232 l->mtu = msg_max_pkt(hdr);
2233 break;
2234
2235 case STATE_MSG:
2236 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2237
2238 /* Update own tolerance if peer indicates a non-zero value */
2239 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2240 l->tolerance = peers_tol;
2241 l->bc_rcvlink->tolerance = peers_tol;
2242 }
2243 /* Update own prio if peer indicates a different value */
2244 if ((peers_prio != l->priority) &&
2245 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2246 l->priority = peers_prio;
2247 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2248 }
2249
2250 l->silent_intv_cnt = 0;
2251 l->stats.recv_states++;
2252 if (msg_probe(hdr))
2253 l->stats.recv_probes++;
2254
2255 if (!link_is_up(l)) {
2256 if (l->state == LINK_ESTABLISHING)
2257 rc = TIPC_LINK_UP_EVT;
2258 break;
2259 }
2260
2261 /* Receive Gap ACK blocks from peer if any */
2262 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2263
2264 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2265 &l->mon_state, l->bearer_id);
2266
2267 /* Send NACK if peer has sent pkts we haven't received yet */
2268 if ((reply || msg_is_keepalive(hdr)) &&
2269 more(peers_snd_nxt, rcv_nxt) &&
2270 !tipc_link_is_synching(l) &&
2271 skb_queue_empty(&l->deferdq))
2272 rcvgap = peers_snd_nxt - l->rcv_nxt;
2273 if (rcvgap || reply)
2274 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2275 rcvgap, 0, 0, xmitq);
2276
2277 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2278 &retransmitted, &rc);
2279 if (gap)
2280 l->stats.recv_nacks++;
2281 if (released || retransmitted)
2282 tipc_link_update_cwin(l, released, retransmitted);
2283 if (released)
2284 tipc_link_advance_backlog(l, xmitq);
2285 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2286 link_prepare_wakeup(l);
2287 }
2288exit:
2289 kfree_skb(skb);
2290 return rc;
2291}
2292
2293/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2294 */
2295static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2296 u16 peers_snd_nxt,
2297 struct sk_buff_head *xmitq)
2298{
2299 struct sk_buff *skb;
2300 struct tipc_msg *hdr;
2301 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2302 u16 ack = l->rcv_nxt - 1;
2303 u16 gap_to = peers_snd_nxt - 1;
2304
2305 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2306 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2307 if (!skb)
2308 return false;
2309 hdr = buf_msg(skb);
2310 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2311 msg_set_bcast_ack(hdr, ack);
2312 msg_set_bcgap_after(hdr, ack);
2313 if (dfrd_skb)
2314 gap_to = buf_seqno(dfrd_skb) - 1;
2315 msg_set_bcgap_to(hdr, gap_to);
2316 msg_set_non_seq(hdr, bcast);
2317 __skb_queue_tail(xmitq, skb);
2318 return true;
2319}
2320
2321/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2322 *
2323 * Give a newly added peer node the sequence number where it should
2324 * start receiving and acking broadcast packets.
2325 */
2326static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2327 struct sk_buff_head *xmitq)
2328{
2329 struct sk_buff_head list;
2330
2331 __skb_queue_head_init(&list);
2332 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2333 return;
2334 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2335 tipc_link_xmit(l, &list, xmitq);
2336}
2337
2338/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2339 */
2340void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2341{
2342 int mtyp = msg_type(hdr);
2343 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2344
2345 if (link_is_up(l))
2346 return;
2347
2348 if (msg_user(hdr) == BCAST_PROTOCOL) {
2349 l->rcv_nxt = peers_snd_nxt;
2350 l->state = LINK_ESTABLISHED;
2351 return;
2352 }
2353
2354 if (l->peer_caps & TIPC_BCAST_SYNCH)
2355 return;
2356
2357 if (msg_peer_node_is_up(hdr))
2358 return;
2359
2360 /* Compatibility: accept older, less safe initial synch data */
2361 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2362 l->rcv_nxt = peers_snd_nxt;
2363}
2364
2365/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2366 */
2367int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2368 struct sk_buff_head *xmitq)
2369{
2370 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2371 int rc = 0;
2372
2373 if (!link_is_up(l))
2374 return rc;
2375
2376 if (!msg_peer_node_is_up(hdr))
2377 return rc;
2378
2379 /* Open when peer ackowledges our bcast init msg (pkt #1) */
2380 if (msg_ack(hdr))
2381 l->bc_peer_is_up = true;
2382
2383 if (!l->bc_peer_is_up)
2384 return rc;
2385
2386 /* Ignore if peers_snd_nxt goes beyond receive window */
2387 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2388 return rc;
2389
2390 l->snd_nxt = peers_snd_nxt;
2391 if (link_bc_rcv_gap(l))
2392 rc |= TIPC_LINK_SND_STATE;
2393
2394 /* Return now if sender supports nack via STATE messages */
2395 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2396 return rc;
2397
2398 /* Otherwise, be backwards compatible */
2399
2400 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2401 l->nack_state = BC_NACK_SND_CONDITIONAL;
2402 return 0;
2403 }
2404
2405 /* Don't NACK if one was recently sent or peeked */
2406 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2407 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2408 return 0;
2409 }
2410
2411 /* Conditionally delay NACK sending until next synch rcv */
2412 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2413 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2414 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2415 return 0;
2416 }
2417
2418 /* Send NACK now but suppress next one */
2419 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2420 l->nack_state = BC_NACK_SND_SUPPRESS;
2421 return 0;
2422}
2423
2424int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2425 struct tipc_gap_ack_blks *ga,
2426 struct sk_buff_head *xmitq,
2427 struct sk_buff_head *retrq)
2428{
2429 struct tipc_link *l = r->bc_sndlink;
2430 bool unused = false;
2431 int rc = 0;
2432
2433 if (!link_is_up(r) || !r->bc_peer_is_up)
2434 return 0;
2435
2436 if (gap) {
2437 l->stats.recv_nacks++;
2438 r->stats.recv_nacks++;
2439 }
2440
2441 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2442 return 0;
2443
2444 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2445 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2446
2447 tipc_link_advance_backlog(l, xmitq);
2448 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2449 link_prepare_wakeup(l);
2450
2451 return rc;
2452}
2453
2454/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2455 * This function is here for backwards compatibility, since
2456 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2457 */
2458int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2459 struct sk_buff_head *xmitq)
2460{
2461 struct tipc_msg *hdr = buf_msg(skb);
2462 u32 dnode = msg_destnode(hdr);
2463 int mtyp = msg_type(hdr);
2464 u16 acked = msg_bcast_ack(hdr);
2465 u16 from = acked + 1;
2466 u16 to = msg_bcgap_to(hdr);
2467 u16 peers_snd_nxt = to + 1;
2468 int rc = 0;
2469
2470 kfree_skb(skb);
2471
2472 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2473 return 0;
2474
2475 if (mtyp != STATE_MSG)
2476 return 0;
2477
2478 if (dnode == tipc_own_addr(l->net)) {
2479 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2480 xmitq);
2481 l->stats.recv_nacks++;
2482 return rc;
2483 }
2484
2485 /* Msg for other node => suppress own NACK at next sync if applicable */
2486 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2487 l->nack_state = BC_NACK_SND_SUPPRESS;
2488
2489 return 0;
2490}
2491
2492void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2493{
2494 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2495
2496 l->min_win = min_win;
2497 l->ssthresh = max_win;
2498 l->max_win = max_win;
2499 l->window = min_win;
2500 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2501 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2502 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2503 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2504 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2505}
2506
2507/**
2508 * link_reset_stats - reset link statistics
2509 * @l: pointer to link
2510 */
2511void tipc_link_reset_stats(struct tipc_link *l)
2512{
2513 memset(&l->stats, 0, sizeof(l->stats));
2514}
2515
2516static void link_print(struct tipc_link *l, const char *str)
2517{
2518 struct sk_buff *hskb = skb_peek(&l->transmq);
2519 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2520 u16 tail = l->snd_nxt - 1;
2521
2522 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2523 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2524 skb_queue_len(&l->transmq), head, tail,
2525 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2526}
2527
2528/* Parse and validate nested (link) properties valid for media, bearer and link
2529 */
2530int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2531{
2532 int err;
2533
2534 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2535 tipc_nl_prop_policy, NULL);
2536 if (err)
2537 return err;
2538
2539 if (props[TIPC_NLA_PROP_PRIO]) {
2540 u32 prio;
2541
2542 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2543 if (prio > TIPC_MAX_LINK_PRI)
2544 return -EINVAL;
2545 }
2546
2547 if (props[TIPC_NLA_PROP_TOL]) {
2548 u32 tol;
2549
2550 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2551 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2552 return -EINVAL;
2553 }
2554
2555 if (props[TIPC_NLA_PROP_WIN]) {
2556 u32 max_win;
2557
2558 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2559 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2560 return -EINVAL;
2561 }
2562
2563 return 0;
2564}
2565
2566static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2567{
2568 int i;
2569 struct nlattr *stats;
2570
2571 struct nla_map {
2572 u32 key;
2573 u32 val;
2574 };
2575
2576 struct nla_map map[] = {
2577 {TIPC_NLA_STATS_RX_INFO, 0},
2578 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2579 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2580 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2581 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2582 {TIPC_NLA_STATS_TX_INFO, 0},
2583 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2584 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2585 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2586 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2587 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2588 s->msg_length_counts : 1},
2589 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2590 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2591 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2592 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2593 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2594 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2595 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2596 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2597 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2598 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2599 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2600 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2601 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2602 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2603 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2604 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2605 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2606 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2607 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2608 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2609 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2610 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2611 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2612 };
2613
2614 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2615 if (!stats)
2616 return -EMSGSIZE;
2617
2618 for (i = 0; i < ARRAY_SIZE(map); i++)
2619 if (nla_put_u32(skb, map[i].key, map[i].val))
2620 goto msg_full;
2621
2622 nla_nest_end(skb, stats);
2623
2624 return 0;
2625msg_full:
2626 nla_nest_cancel(skb, stats);
2627
2628 return -EMSGSIZE;
2629}
2630
2631/* Caller should hold appropriate locks to protect the link */
2632int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2633 struct tipc_link *link, int nlflags)
2634{
2635 u32 self = tipc_own_addr(net);
2636 struct nlattr *attrs;
2637 struct nlattr *prop;
2638 void *hdr;
2639 int err;
2640
2641 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2642 nlflags, TIPC_NL_LINK_GET);
2643 if (!hdr)
2644 return -EMSGSIZE;
2645
2646 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2647 if (!attrs)
2648 goto msg_full;
2649
2650 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2651 goto attr_msg_full;
2652 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2653 goto attr_msg_full;
2654 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2655 goto attr_msg_full;
2656 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2657 goto attr_msg_full;
2658 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2659 goto attr_msg_full;
2660
2661 if (tipc_link_is_up(link))
2662 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2663 goto attr_msg_full;
2664 if (link->active)
2665 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2666 goto attr_msg_full;
2667
2668 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2669 if (!prop)
2670 goto attr_msg_full;
2671 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2672 goto prop_msg_full;
2673 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2674 goto prop_msg_full;
2675 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2676 link->window))
2677 goto prop_msg_full;
2678 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2679 goto prop_msg_full;
2680 nla_nest_end(msg->skb, prop);
2681
2682 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2683 if (err)
2684 goto attr_msg_full;
2685
2686 nla_nest_end(msg->skb, attrs);
2687 genlmsg_end(msg->skb, hdr);
2688
2689 return 0;
2690
2691prop_msg_full:
2692 nla_nest_cancel(msg->skb, prop);
2693attr_msg_full:
2694 nla_nest_cancel(msg->skb, attrs);
2695msg_full:
2696 genlmsg_cancel(msg->skb, hdr);
2697
2698 return -EMSGSIZE;
2699}
2700
2701static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2702 struct tipc_stats *stats)
2703{
2704 int i;
2705 struct nlattr *nest;
2706
2707 struct nla_map {
2708 __u32 key;
2709 __u32 val;
2710 };
2711
2712 struct nla_map map[] = {
2713 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2714 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2715 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2716 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2717 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2718 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2719 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2720 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2721 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2722 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2723 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2724 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2725 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2726 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2727 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2728 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2729 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2730 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2731 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2732 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2733 };
2734
2735 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2736 if (!nest)
2737 return -EMSGSIZE;
2738
2739 for (i = 0; i < ARRAY_SIZE(map); i++)
2740 if (nla_put_u32(skb, map[i].key, map[i].val))
2741 goto msg_full;
2742
2743 nla_nest_end(skb, nest);
2744
2745 return 0;
2746msg_full:
2747 nla_nest_cancel(skb, nest);
2748
2749 return -EMSGSIZE;
2750}
2751
2752int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2753 struct tipc_link *bcl)
2754{
2755 int err;
2756 void *hdr;
2757 struct nlattr *attrs;
2758 struct nlattr *prop;
2759 u32 bc_mode = tipc_bcast_get_mode(net);
2760 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2761
2762 if (!bcl)
2763 return 0;
2764
2765 tipc_bcast_lock(net);
2766
2767 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2768 NLM_F_MULTI, TIPC_NL_LINK_GET);
2769 if (!hdr) {
2770 tipc_bcast_unlock(net);
2771 return -EMSGSIZE;
2772 }
2773
2774 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2775 if (!attrs)
2776 goto msg_full;
2777
2778 /* The broadcast link is always up */
2779 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2780 goto attr_msg_full;
2781
2782 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2783 goto attr_msg_full;
2784 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2785 goto attr_msg_full;
2786 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2787 goto attr_msg_full;
2788 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2789 goto attr_msg_full;
2790
2791 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2792 if (!prop)
2793 goto attr_msg_full;
2794 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2795 goto prop_msg_full;
2796 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2797 goto prop_msg_full;
2798 if (bc_mode & BCLINK_MODE_SEL)
2799 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2800 bc_ratio))
2801 goto prop_msg_full;
2802 nla_nest_end(msg->skb, prop);
2803
2804 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2805 if (err)
2806 goto attr_msg_full;
2807
2808 tipc_bcast_unlock(net);
2809 nla_nest_end(msg->skb, attrs);
2810 genlmsg_end(msg->skb, hdr);
2811
2812 return 0;
2813
2814prop_msg_full:
2815 nla_nest_cancel(msg->skb, prop);
2816attr_msg_full:
2817 nla_nest_cancel(msg->skb, attrs);
2818msg_full:
2819 tipc_bcast_unlock(net);
2820 genlmsg_cancel(msg->skb, hdr);
2821
2822 return -EMSGSIZE;
2823}
2824
2825void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2826 struct sk_buff_head *xmitq)
2827{
2828 l->tolerance = tol;
2829 if (l->bc_rcvlink)
2830 l->bc_rcvlink->tolerance = tol;
2831 if (link_is_up(l))
2832 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2833}
2834
2835void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2836 struct sk_buff_head *xmitq)
2837{
2838 l->priority = prio;
2839 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2840}
2841
2842void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2843{
2844 l->abort_limit = limit;
2845}
2846
2847/**
2848 * tipc_link_dump - dump TIPC link data
2849 * @l: tipc link to be dumped
2850 * @dqueues: bitmask to decide if any link queue to be dumped?
2851 * - TIPC_DUMP_NONE: don't dump link queues
2852 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2853 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2854 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2855 * - TIPC_DUMP_INPUTQ: dump link input queue
2856 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2857 * - TIPC_DUMP_ALL: dump all the link queues above
2858 * @buf: returned buffer of dump data in format
2859 */
2860int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2861{
2862 int i = 0;
2863 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2864 struct sk_buff_head *list;
2865 struct sk_buff *hskb, *tskb;
2866 u32 len;
2867
2868 if (!l) {
2869 i += scnprintf(buf, sz, "link data: (null)\n");
2870 return i;
2871 }
2872
2873 i += scnprintf(buf, sz, "link data: %x", l->addr);
2874 i += scnprintf(buf + i, sz - i, " %x", l->state);
2875 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2876 i += scnprintf(buf + i, sz - i, " %u", l->session);
2877 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2878 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2879 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2880 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2881 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2882 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2883 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2884 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2885 i += scnprintf(buf + i, sz - i, " %u", 0);
2886 i += scnprintf(buf + i, sz - i, " %u", 0);
2887 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2888
2889 list = &l->transmq;
2890 len = skb_queue_len(list);
2891 hskb = skb_peek(list);
2892 tskb = skb_peek_tail(list);
2893 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2894 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2895 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2896
2897 list = &l->deferdq;
2898 len = skb_queue_len(list);
2899 hskb = skb_peek(list);
2900 tskb = skb_peek_tail(list);
2901 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2902 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2903 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2904
2905 list = &l->backlogq;
2906 len = skb_queue_len(list);
2907 hskb = skb_peek(list);
2908 tskb = skb_peek_tail(list);
2909 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2910 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2911 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2912
2913 list = l->inputq;
2914 len = skb_queue_len(list);
2915 hskb = skb_peek(list);
2916 tskb = skb_peek_tail(list);
2917 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2918 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2919 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2920
2921 if (dqueues & TIPC_DUMP_TRANSMQ) {
2922 i += scnprintf(buf + i, sz - i, "transmq: ");
2923 i += tipc_list_dump(&l->transmq, false, buf + i);
2924 }
2925 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2926 i += scnprintf(buf + i, sz - i,
2927 "backlogq: <%u %u %u %u %u>, ",
2928 l->backlog[TIPC_LOW_IMPORTANCE].len,
2929 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2930 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2931 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2932 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2933 i += tipc_list_dump(&l->backlogq, false, buf + i);
2934 }
2935 if (dqueues & TIPC_DUMP_DEFERDQ) {
2936 i += scnprintf(buf + i, sz - i, "deferdq: ");
2937 i += tipc_list_dump(&l->deferdq, false, buf + i);
2938 }
2939 if (dqueues & TIPC_DUMP_INPUTQ) {
2940 i += scnprintf(buf + i, sz - i, "inputq: ");
2941 i += tipc_list_dump(l->inputq, false, buf + i);
2942 }
2943 if (dqueues & TIPC_DUMP_WAKEUP) {
2944 i += scnprintf(buf + i, sz - i, "wakeup: ");
2945 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2946 }
2947
2948 return i;
2949}
1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "subscr.h"
39#include "link.h"
40#include "bcast.h"
41#include "socket.h"
42#include "name_distr.h"
43#include "discover.h"
44#include "netlink.h"
45#include "monitor.h"
46#include "trace.h"
47
48#include <linux/pkt_sched.h>
49
50struct tipc_stats {
51 u32 sent_pkts;
52 u32 recv_pkts;
53 u32 sent_states;
54 u32 recv_states;
55 u32 sent_probes;
56 u32 recv_probes;
57 u32 sent_nacks;
58 u32 recv_nacks;
59 u32 sent_acks;
60 u32 sent_bundled;
61 u32 sent_bundles;
62 u32 recv_bundled;
63 u32 recv_bundles;
64 u32 retransmitted;
65 u32 sent_fragmented;
66 u32 sent_fragments;
67 u32 recv_fragmented;
68 u32 recv_fragments;
69 u32 link_congs; /* # port sends blocked by congestion */
70 u32 deferred_recv;
71 u32 duplicates;
72 u32 max_queue_sz; /* send queue size high water mark */
73 u32 accu_queue_sz; /* used for send queue size profiling */
74 u32 queue_sz_counts; /* used for send queue size profiling */
75 u32 msg_length_counts; /* used for message length profiling */
76 u32 msg_lengths_total; /* used for message length profiling */
77 u32 msg_length_profile[7]; /* used for msg. length profiling */
78};
79
80/**
81 * struct tipc_link - TIPC link data structure
82 * @addr: network address of link's peer node
83 * @name: link name character string
84 * @media_addr: media address to use when sending messages over link
85 * @timer: link timer
86 * @net: pointer to namespace struct
87 * @refcnt: reference counter for permanent references (owner node & timer)
88 * @peer_session: link session # being used by peer end of link
89 * @peer_bearer_id: bearer id used by link's peer endpoint
90 * @bearer_id: local bearer id used by link
91 * @tolerance: minimum link continuity loss needed to reset link [in ms]
92 * @abort_limit: # of unacknowledged continuity probes needed to reset link
93 * @state: current state of link FSM
94 * @peer_caps: bitmap describing capabilities of peer node
95 * @silent_intv_cnt: # of timer intervals without any reception from peer
96 * @proto_msg: template for control messages generated by link
97 * @pmsg: convenience pointer to "proto_msg" field
98 * @priority: current link priority
99 * @net_plane: current link network plane ('A' through 'H')
100 * @mon_state: cookie with information needed by link monitor
101 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
102 * @exp_msg_count: # of tunnelled messages expected during link changeover
103 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
104 * @mtu: current maximum packet size for this link
105 * @advertised_mtu: advertised own mtu when link is being established
106 * @transmitq: queue for sent, non-acked messages
107 * @backlogq: queue for messages waiting to be sent
108 * @snt_nxt: next sequence number to use for outbound messages
109 * @ackers: # of peers that needs to ack each packet before it can be released
110 * @acked: # last packet acked by a certain peer. Used for broadcast.
111 * @rcv_nxt: next sequence number to expect for inbound messages
112 * @deferred_queue: deferred queue saved OOS b'cast message received from node
113 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
114 * @inputq: buffer queue for messages to be delivered upwards
115 * @namedq: buffer queue for name table messages to be delivered upwards
116 * @next_out: ptr to first unsent outbound message in queue
117 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
118 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
119 * @reasm_buf: head of partially reassembled inbound message fragments
120 * @bc_rcvr: marks that this is a broadcast receiver link
121 * @stats: collects statistics regarding link activity
122 */
123struct tipc_link {
124 u32 addr;
125 char name[TIPC_MAX_LINK_NAME];
126 struct net *net;
127
128 /* Management and link supervision data */
129 u16 peer_session;
130 u16 session;
131 u16 snd_nxt_state;
132 u16 rcv_nxt_state;
133 u32 peer_bearer_id;
134 u32 bearer_id;
135 u32 tolerance;
136 u32 abort_limit;
137 u32 state;
138 u16 peer_caps;
139 bool in_session;
140 bool active;
141 u32 silent_intv_cnt;
142 char if_name[TIPC_MAX_IF_NAME];
143 u32 priority;
144 char net_plane;
145 struct tipc_mon_state mon_state;
146 u16 rst_cnt;
147
148 /* Failover/synch */
149 u16 drop_point;
150 struct sk_buff *failover_reasm_skb;
151 struct sk_buff_head failover_deferdq;
152
153 /* Max packet negotiation */
154 u16 mtu;
155 u16 advertised_mtu;
156
157 /* Sending */
158 struct sk_buff_head transmq;
159 struct sk_buff_head backlogq;
160 struct {
161 u16 len;
162 u16 limit;
163 struct sk_buff *target_bskb;
164 } backlog[5];
165 u16 snd_nxt;
166 u16 window;
167
168 /* Reception */
169 u16 rcv_nxt;
170 u32 rcv_unacked;
171 struct sk_buff_head deferdq;
172 struct sk_buff_head *inputq;
173 struct sk_buff_head *namedq;
174
175 /* Congestion handling */
176 struct sk_buff_head wakeupq;
177
178 /* Fragmentation/reassembly */
179 struct sk_buff *reasm_buf;
180 struct sk_buff *reasm_tnlmsg;
181
182 /* Broadcast */
183 u16 ackers;
184 u16 acked;
185 struct tipc_link *bc_rcvlink;
186 struct tipc_link *bc_sndlink;
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_LIM (jiffies + msecs_to_jiffies(10))
209#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
210
211/*
212 * Interval between NACKs when packets arrive out of order
213 */
214#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
215
216/* Link FSM states:
217 */
218enum {
219 LINK_ESTABLISHED = 0xe,
220 LINK_ESTABLISHING = 0xe << 4,
221 LINK_RESET = 0x1 << 8,
222 LINK_RESETTING = 0x2 << 12,
223 LINK_PEER_RESET = 0xd << 16,
224 LINK_FAILINGOVER = 0xf << 20,
225 LINK_SYNCHING = 0xc << 24
226};
227
228/* Link FSM state checking routines
229 */
230static int link_is_up(struct tipc_link *l)
231{
232 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
233}
234
235static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
236 struct sk_buff_head *xmitq);
237static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
238 bool probe_reply, u16 rcvgap,
239 int tolerance, int priority,
240 struct sk_buff_head *xmitq);
241static void link_print(struct tipc_link *l, const char *str);
242static int tipc_link_build_nack_msg(struct tipc_link *l,
243 struct sk_buff_head *xmitq);
244static void tipc_link_build_bc_init_msg(struct tipc_link *l,
245 struct sk_buff_head *xmitq);
246static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
247static u16 tipc_build_gap_ack_blks(struct tipc_link *l, void *data);
248static int tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap,
249 struct tipc_gap_ack_blks *ga,
250 struct sk_buff_head *xmitq);
251
252/*
253 * Simple non-static link routines (i.e. referenced outside this file)
254 */
255bool tipc_link_is_up(struct tipc_link *l)
256{
257 return link_is_up(l);
258}
259
260bool tipc_link_peer_is_down(struct tipc_link *l)
261{
262 return l->state == LINK_PEER_RESET;
263}
264
265bool tipc_link_is_reset(struct tipc_link *l)
266{
267 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
268}
269
270bool tipc_link_is_establishing(struct tipc_link *l)
271{
272 return l->state == LINK_ESTABLISHING;
273}
274
275bool tipc_link_is_synching(struct tipc_link *l)
276{
277 return l->state == LINK_SYNCHING;
278}
279
280bool tipc_link_is_failingover(struct tipc_link *l)
281{
282 return l->state == LINK_FAILINGOVER;
283}
284
285bool tipc_link_is_blocked(struct tipc_link *l)
286{
287 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
288}
289
290static bool link_is_bc_sndlink(struct tipc_link *l)
291{
292 return !l->bc_sndlink;
293}
294
295static bool link_is_bc_rcvlink(struct tipc_link *l)
296{
297 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
298}
299
300void tipc_link_set_active(struct tipc_link *l, bool active)
301{
302 l->active = active;
303}
304
305u32 tipc_link_id(struct tipc_link *l)
306{
307 return l->peer_bearer_id << 16 | l->bearer_id;
308}
309
310int tipc_link_window(struct tipc_link *l)
311{
312 return l->window;
313}
314
315int tipc_link_prio(struct tipc_link *l)
316{
317 return l->priority;
318}
319
320unsigned long tipc_link_tolerance(struct tipc_link *l)
321{
322 return l->tolerance;
323}
324
325struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
326{
327 return l->inputq;
328}
329
330char tipc_link_plane(struct tipc_link *l)
331{
332 return l->net_plane;
333}
334
335void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
336{
337 l->peer_caps = capabilities;
338}
339
340void tipc_link_add_bc_peer(struct tipc_link *snd_l,
341 struct tipc_link *uc_l,
342 struct sk_buff_head *xmitq)
343{
344 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
345
346 snd_l->ackers++;
347 rcv_l->acked = snd_l->snd_nxt - 1;
348 snd_l->state = LINK_ESTABLISHED;
349 tipc_link_build_bc_init_msg(uc_l, xmitq);
350}
351
352void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
353 struct tipc_link *rcv_l,
354 struct sk_buff_head *xmitq)
355{
356 u16 ack = snd_l->snd_nxt - 1;
357
358 snd_l->ackers--;
359 rcv_l->bc_peer_is_up = true;
360 rcv_l->state = LINK_ESTABLISHED;
361 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
362 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
363 tipc_link_reset(rcv_l);
364 rcv_l->state = LINK_RESET;
365 if (!snd_l->ackers) {
366 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
367 tipc_link_reset(snd_l);
368 snd_l->state = LINK_RESET;
369 __skb_queue_purge(xmitq);
370 }
371}
372
373int tipc_link_bc_peers(struct tipc_link *l)
374{
375 return l->ackers;
376}
377
378static u16 link_bc_rcv_gap(struct tipc_link *l)
379{
380 struct sk_buff *skb = skb_peek(&l->deferdq);
381 u16 gap = 0;
382
383 if (more(l->snd_nxt, l->rcv_nxt))
384 gap = l->snd_nxt - l->rcv_nxt;
385 if (skb)
386 gap = buf_seqno(skb) - l->rcv_nxt;
387 return gap;
388}
389
390void tipc_link_set_mtu(struct tipc_link *l, int mtu)
391{
392 l->mtu = mtu;
393}
394
395int tipc_link_mtu(struct tipc_link *l)
396{
397 return l->mtu;
398}
399
400u16 tipc_link_rcv_nxt(struct tipc_link *l)
401{
402 return l->rcv_nxt;
403}
404
405u16 tipc_link_acked(struct tipc_link *l)
406{
407 return l->acked;
408}
409
410char *tipc_link_name(struct tipc_link *l)
411{
412 return l->name;
413}
414
415u32 tipc_link_state(struct tipc_link *l)
416{
417 return l->state;
418}
419
420/**
421 * tipc_link_create - create a new link
422 * @n: pointer to associated node
423 * @if_name: associated interface name
424 * @bearer_id: id (index) of associated bearer
425 * @tolerance: link tolerance to be used by link
426 * @net_plane: network plane (A,B,c..) this link belongs to
427 * @mtu: mtu to be advertised by link
428 * @priority: priority to be used by link
429 * @window: send window to be used by link
430 * @session: session to be used by link
431 * @ownnode: identity of own node
432 * @peer: node id of peer node
433 * @peer_caps: bitmap describing peer node capabilities
434 * @bc_sndlink: the namespace global link used for broadcast sending
435 * @bc_rcvlink: the peer specific link used for broadcast reception
436 * @inputq: queue to put messages ready for delivery
437 * @namedq: queue to put binding table update messages ready for delivery
438 * @link: return value, pointer to put the created link
439 *
440 * Returns true if link was created, otherwise false
441 */
442bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
443 int tolerance, char net_plane, u32 mtu, int priority,
444 int window, u32 session, u32 self,
445 u32 peer, u8 *peer_id, u16 peer_caps,
446 struct tipc_link *bc_sndlink,
447 struct tipc_link *bc_rcvlink,
448 struct sk_buff_head *inputq,
449 struct sk_buff_head *namedq,
450 struct tipc_link **link)
451{
452 char peer_str[NODE_ID_STR_LEN] = {0,};
453 char self_str[NODE_ID_STR_LEN] = {0,};
454 struct tipc_link *l;
455
456 l = kzalloc(sizeof(*l), GFP_ATOMIC);
457 if (!l)
458 return false;
459 *link = l;
460 l->session = session;
461
462 /* Set link name for unicast links only */
463 if (peer_id) {
464 tipc_nodeid2string(self_str, tipc_own_id(net));
465 if (strlen(self_str) > 16)
466 sprintf(self_str, "%x", self);
467 tipc_nodeid2string(peer_str, peer_id);
468 if (strlen(peer_str) > 16)
469 sprintf(peer_str, "%x", peer);
470 }
471 /* Peer i/f name will be completed by reset/activate message */
472 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
473 self_str, if_name, peer_str);
474
475 strcpy(l->if_name, if_name);
476 l->addr = peer;
477 l->peer_caps = peer_caps;
478 l->net = net;
479 l->in_session = false;
480 l->bearer_id = bearer_id;
481 l->tolerance = tolerance;
482 if (bc_rcvlink)
483 bc_rcvlink->tolerance = tolerance;
484 l->net_plane = net_plane;
485 l->advertised_mtu = mtu;
486 l->mtu = mtu;
487 l->priority = priority;
488 tipc_link_set_queue_limits(l, window);
489 l->ackers = 1;
490 l->bc_sndlink = bc_sndlink;
491 l->bc_rcvlink = bc_rcvlink;
492 l->inputq = inputq;
493 l->namedq = namedq;
494 l->state = LINK_RESETTING;
495 __skb_queue_head_init(&l->transmq);
496 __skb_queue_head_init(&l->backlogq);
497 __skb_queue_head_init(&l->deferdq);
498 __skb_queue_head_init(&l->failover_deferdq);
499 skb_queue_head_init(&l->wakeupq);
500 skb_queue_head_init(l->inputq);
501 return true;
502}
503
504/**
505 * tipc_link_bc_create - create new link to be used for broadcast
506 * @n: pointer to associated node
507 * @mtu: mtu to be used initially if no peers
508 * @window: send window to be used
509 * @inputq: queue to put messages ready for delivery
510 * @namedq: queue to put binding table update messages ready for delivery
511 * @link: return value, pointer to put the created link
512 *
513 * Returns true if link was created, otherwise false
514 */
515bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
516 int mtu, int window, u16 peer_caps,
517 struct sk_buff_head *inputq,
518 struct sk_buff_head *namedq,
519 struct tipc_link *bc_sndlink,
520 struct tipc_link **link)
521{
522 struct tipc_link *l;
523
524 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
525 0, ownnode, peer, NULL, peer_caps, bc_sndlink,
526 NULL, inputq, namedq, link))
527 return false;
528
529 l = *link;
530 strcpy(l->name, tipc_bclink_name);
531 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
532 tipc_link_reset(l);
533 l->state = LINK_RESET;
534 l->ackers = 0;
535 l->bc_rcvlink = l;
536
537 /* Broadcast send link is always up */
538 if (link_is_bc_sndlink(l))
539 l->state = LINK_ESTABLISHED;
540
541 /* Disable replicast if even a single peer doesn't support it */
542 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
543 tipc_bcast_disable_rcast(net);
544
545 return true;
546}
547
548/**
549 * tipc_link_fsm_evt - link finite state machine
550 * @l: pointer to link
551 * @evt: state machine event to be processed
552 */
553int tipc_link_fsm_evt(struct tipc_link *l, int evt)
554{
555 int rc = 0;
556 int old_state = l->state;
557
558 switch (l->state) {
559 case LINK_RESETTING:
560 switch (evt) {
561 case LINK_PEER_RESET_EVT:
562 l->state = LINK_PEER_RESET;
563 break;
564 case LINK_RESET_EVT:
565 l->state = LINK_RESET;
566 break;
567 case LINK_FAILURE_EVT:
568 case LINK_FAILOVER_BEGIN_EVT:
569 case LINK_ESTABLISH_EVT:
570 case LINK_FAILOVER_END_EVT:
571 case LINK_SYNCH_BEGIN_EVT:
572 case LINK_SYNCH_END_EVT:
573 default:
574 goto illegal_evt;
575 }
576 break;
577 case LINK_RESET:
578 switch (evt) {
579 case LINK_PEER_RESET_EVT:
580 l->state = LINK_ESTABLISHING;
581 break;
582 case LINK_FAILOVER_BEGIN_EVT:
583 l->state = LINK_FAILINGOVER;
584 case LINK_FAILURE_EVT:
585 case LINK_RESET_EVT:
586 case LINK_ESTABLISH_EVT:
587 case LINK_FAILOVER_END_EVT:
588 break;
589 case LINK_SYNCH_BEGIN_EVT:
590 case LINK_SYNCH_END_EVT:
591 default:
592 goto illegal_evt;
593 }
594 break;
595 case LINK_PEER_RESET:
596 switch (evt) {
597 case LINK_RESET_EVT:
598 l->state = LINK_ESTABLISHING;
599 break;
600 case LINK_PEER_RESET_EVT:
601 case LINK_ESTABLISH_EVT:
602 case LINK_FAILURE_EVT:
603 break;
604 case LINK_SYNCH_BEGIN_EVT:
605 case LINK_SYNCH_END_EVT:
606 case LINK_FAILOVER_BEGIN_EVT:
607 case LINK_FAILOVER_END_EVT:
608 default:
609 goto illegal_evt;
610 }
611 break;
612 case LINK_FAILINGOVER:
613 switch (evt) {
614 case LINK_FAILOVER_END_EVT:
615 l->state = LINK_RESET;
616 break;
617 case LINK_PEER_RESET_EVT:
618 case LINK_RESET_EVT:
619 case LINK_ESTABLISH_EVT:
620 case LINK_FAILURE_EVT:
621 break;
622 case LINK_FAILOVER_BEGIN_EVT:
623 case LINK_SYNCH_BEGIN_EVT:
624 case LINK_SYNCH_END_EVT:
625 default:
626 goto illegal_evt;
627 }
628 break;
629 case LINK_ESTABLISHING:
630 switch (evt) {
631 case LINK_ESTABLISH_EVT:
632 l->state = LINK_ESTABLISHED;
633 break;
634 case LINK_FAILOVER_BEGIN_EVT:
635 l->state = LINK_FAILINGOVER;
636 break;
637 case LINK_RESET_EVT:
638 l->state = LINK_RESET;
639 break;
640 case LINK_FAILURE_EVT:
641 case LINK_PEER_RESET_EVT:
642 case LINK_SYNCH_BEGIN_EVT:
643 case LINK_FAILOVER_END_EVT:
644 break;
645 case LINK_SYNCH_END_EVT:
646 default:
647 goto illegal_evt;
648 }
649 break;
650 case LINK_ESTABLISHED:
651 switch (evt) {
652 case LINK_PEER_RESET_EVT:
653 l->state = LINK_PEER_RESET;
654 rc |= TIPC_LINK_DOWN_EVT;
655 break;
656 case LINK_FAILURE_EVT:
657 l->state = LINK_RESETTING;
658 rc |= TIPC_LINK_DOWN_EVT;
659 break;
660 case LINK_RESET_EVT:
661 l->state = LINK_RESET;
662 break;
663 case LINK_ESTABLISH_EVT:
664 case LINK_SYNCH_END_EVT:
665 break;
666 case LINK_SYNCH_BEGIN_EVT:
667 l->state = LINK_SYNCHING;
668 break;
669 case LINK_FAILOVER_BEGIN_EVT:
670 case LINK_FAILOVER_END_EVT:
671 default:
672 goto illegal_evt;
673 }
674 break;
675 case LINK_SYNCHING:
676 switch (evt) {
677 case LINK_PEER_RESET_EVT:
678 l->state = LINK_PEER_RESET;
679 rc |= TIPC_LINK_DOWN_EVT;
680 break;
681 case LINK_FAILURE_EVT:
682 l->state = LINK_RESETTING;
683 rc |= TIPC_LINK_DOWN_EVT;
684 break;
685 case LINK_RESET_EVT:
686 l->state = LINK_RESET;
687 break;
688 case LINK_ESTABLISH_EVT:
689 case LINK_SYNCH_BEGIN_EVT:
690 break;
691 case LINK_SYNCH_END_EVT:
692 l->state = LINK_ESTABLISHED;
693 break;
694 case LINK_FAILOVER_BEGIN_EVT:
695 case LINK_FAILOVER_END_EVT:
696 default:
697 goto illegal_evt;
698 }
699 break;
700 default:
701 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
702 }
703 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
704 return rc;
705illegal_evt:
706 pr_err("Illegal FSM event %x in state %x on link %s\n",
707 evt, l->state, l->name);
708 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
709 return rc;
710}
711
712/* link_profile_stats - update statistical profiling of traffic
713 */
714static void link_profile_stats(struct tipc_link *l)
715{
716 struct sk_buff *skb;
717 struct tipc_msg *msg;
718 int length;
719
720 /* Update counters used in statistical profiling of send traffic */
721 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
722 l->stats.queue_sz_counts++;
723
724 skb = skb_peek(&l->transmq);
725 if (!skb)
726 return;
727 msg = buf_msg(skb);
728 length = msg_size(msg);
729
730 if (msg_user(msg) == MSG_FRAGMENTER) {
731 if (msg_type(msg) != FIRST_FRAGMENT)
732 return;
733 length = msg_size(msg_inner_hdr(msg));
734 }
735 l->stats.msg_lengths_total += length;
736 l->stats.msg_length_counts++;
737 if (length <= 64)
738 l->stats.msg_length_profile[0]++;
739 else if (length <= 256)
740 l->stats.msg_length_profile[1]++;
741 else if (length <= 1024)
742 l->stats.msg_length_profile[2]++;
743 else if (length <= 4096)
744 l->stats.msg_length_profile[3]++;
745 else if (length <= 16384)
746 l->stats.msg_length_profile[4]++;
747 else if (length <= 32768)
748 l->stats.msg_length_profile[5]++;
749 else
750 l->stats.msg_length_profile[6]++;
751}
752
753/**
754 * tipc_link_too_silent - check if link is "too silent"
755 * @l: tipc link to be checked
756 *
757 * Returns true if the link 'silent_intv_cnt' is about to reach the
758 * 'abort_limit' value, otherwise false
759 */
760bool tipc_link_too_silent(struct tipc_link *l)
761{
762 return (l->silent_intv_cnt + 2 > l->abort_limit);
763}
764
765/* tipc_link_timeout - perform periodic task as instructed from node timeout
766 */
767int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
768{
769 int mtyp = 0;
770 int rc = 0;
771 bool state = false;
772 bool probe = false;
773 bool setup = false;
774 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
775 u16 bc_acked = l->bc_rcvlink->acked;
776 struct tipc_mon_state *mstate = &l->mon_state;
777
778 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
779 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
780 switch (l->state) {
781 case LINK_ESTABLISHED:
782 case LINK_SYNCHING:
783 mtyp = STATE_MSG;
784 link_profile_stats(l);
785 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
786 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
787 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
788 state = bc_acked != bc_snt;
789 state |= l->bc_rcvlink->rcv_unacked;
790 state |= l->rcv_unacked;
791 state |= !skb_queue_empty(&l->transmq);
792 state |= !skb_queue_empty(&l->deferdq);
793 probe = mstate->probing;
794 probe |= l->silent_intv_cnt;
795 if (probe || mstate->monitoring)
796 l->silent_intv_cnt++;
797 break;
798 case LINK_RESET:
799 setup = l->rst_cnt++ <= 4;
800 setup |= !(l->rst_cnt % 16);
801 mtyp = RESET_MSG;
802 break;
803 case LINK_ESTABLISHING:
804 setup = true;
805 mtyp = ACTIVATE_MSG;
806 break;
807 case LINK_PEER_RESET:
808 case LINK_RESETTING:
809 case LINK_FAILINGOVER:
810 break;
811 default:
812 break;
813 }
814
815 if (state || probe || setup)
816 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
817
818 return rc;
819}
820
821/**
822 * link_schedule_user - schedule a message sender for wakeup after congestion
823 * @l: congested link
824 * @hdr: header of message that is being sent
825 * Create pseudo msg to send back to user when congestion abates
826 */
827static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
828{
829 u32 dnode = tipc_own_addr(l->net);
830 u32 dport = msg_origport(hdr);
831 struct sk_buff *skb;
832
833 /* Create and schedule wakeup pseudo message */
834 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
835 dnode, l->addr, dport, 0, 0);
836 if (!skb)
837 return -ENOBUFS;
838 msg_set_dest_droppable(buf_msg(skb), true);
839 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
840 skb_queue_tail(&l->wakeupq, skb);
841 l->stats.link_congs++;
842 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
843 return -ELINKCONG;
844}
845
846/**
847 * link_prepare_wakeup - prepare users for wakeup after congestion
848 * @l: congested link
849 * Wake up a number of waiting users, as permitted by available space
850 * in the send queue
851 */
852static void link_prepare_wakeup(struct tipc_link *l)
853{
854 struct sk_buff_head *wakeupq = &l->wakeupq;
855 struct sk_buff_head *inputq = l->inputq;
856 struct sk_buff *skb, *tmp;
857 struct sk_buff_head tmpq;
858 int avail[5] = {0,};
859 int imp = 0;
860
861 __skb_queue_head_init(&tmpq);
862
863 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
864 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
865
866 skb_queue_walk_safe(wakeupq, skb, tmp) {
867 imp = TIPC_SKB_CB(skb)->chain_imp;
868 if (avail[imp] <= 0)
869 continue;
870 avail[imp]--;
871 __skb_unlink(skb, wakeupq);
872 __skb_queue_tail(&tmpq, skb);
873 }
874
875 spin_lock_bh(&inputq->lock);
876 skb_queue_splice_tail(&tmpq, inputq);
877 spin_unlock_bh(&inputq->lock);
878
879}
880
881void tipc_link_reset(struct tipc_link *l)
882{
883 struct sk_buff_head list;
884 u32 imp;
885
886 __skb_queue_head_init(&list);
887
888 l->in_session = false;
889 /* Force re-synch of peer session number before establishing */
890 l->peer_session--;
891 l->session++;
892 l->mtu = l->advertised_mtu;
893
894 spin_lock_bh(&l->wakeupq.lock);
895 skb_queue_splice_init(&l->wakeupq, &list);
896 spin_unlock_bh(&l->wakeupq.lock);
897
898 spin_lock_bh(&l->inputq->lock);
899 skb_queue_splice_init(&list, l->inputq);
900 spin_unlock_bh(&l->inputq->lock);
901
902 __skb_queue_purge(&l->transmq);
903 __skb_queue_purge(&l->deferdq);
904 __skb_queue_purge(&l->backlogq);
905 __skb_queue_purge(&l->failover_deferdq);
906 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
907 l->backlog[imp].len = 0;
908 l->backlog[imp].target_bskb = NULL;
909 }
910 kfree_skb(l->reasm_buf);
911 kfree_skb(l->reasm_tnlmsg);
912 kfree_skb(l->failover_reasm_skb);
913 l->reasm_buf = NULL;
914 l->reasm_tnlmsg = NULL;
915 l->failover_reasm_skb = NULL;
916 l->rcv_unacked = 0;
917 l->snd_nxt = 1;
918 l->rcv_nxt = 1;
919 l->snd_nxt_state = 1;
920 l->rcv_nxt_state = 1;
921 l->acked = 0;
922 l->silent_intv_cnt = 0;
923 l->rst_cnt = 0;
924 l->bc_peer_is_up = false;
925 memset(&l->mon_state, 0, sizeof(l->mon_state));
926 tipc_link_reset_stats(l);
927}
928
929/**
930 * tipc_link_xmit(): enqueue buffer list according to queue situation
931 * @link: link to use
932 * @list: chain of buffers containing message
933 * @xmitq: returned list of packets to be sent by caller
934 *
935 * Consumes the buffer chain.
936 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
937 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
938 */
939int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
940 struct sk_buff_head *xmitq)
941{
942 struct tipc_msg *hdr = buf_msg(skb_peek(list));
943 unsigned int maxwin = l->window;
944 int imp = msg_importance(hdr);
945 unsigned int mtu = l->mtu;
946 u16 ack = l->rcv_nxt - 1;
947 u16 seqno = l->snd_nxt;
948 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
949 struct sk_buff_head *transmq = &l->transmq;
950 struct sk_buff_head *backlogq = &l->backlogq;
951 struct sk_buff *skb, *_skb, **tskb;
952 int pkt_cnt = skb_queue_len(list);
953 int rc = 0;
954
955 if (unlikely(msg_size(hdr) > mtu)) {
956 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
957 skb_queue_len(list), msg_user(hdr),
958 msg_type(hdr), msg_size(hdr), mtu);
959 __skb_queue_purge(list);
960 return -EMSGSIZE;
961 }
962
963 /* Allow oversubscription of one data msg per source at congestion */
964 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
965 if (imp == TIPC_SYSTEM_IMPORTANCE) {
966 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
967 return -ENOBUFS;
968 }
969 rc = link_schedule_user(l, hdr);
970 }
971
972 if (pkt_cnt > 1) {
973 l->stats.sent_fragmented++;
974 l->stats.sent_fragments += pkt_cnt;
975 }
976
977 /* Prepare each packet for sending, and add to relevant queue: */
978 while (skb_queue_len(list)) {
979 skb = skb_peek(list);
980 hdr = buf_msg(skb);
981 msg_set_seqno(hdr, seqno);
982 msg_set_ack(hdr, ack);
983 msg_set_bcast_ack(hdr, bc_ack);
984
985 if (likely(skb_queue_len(transmq) < maxwin)) {
986 _skb = skb_clone(skb, GFP_ATOMIC);
987 if (!_skb) {
988 __skb_queue_purge(list);
989 return -ENOBUFS;
990 }
991 __skb_dequeue(list);
992 __skb_queue_tail(transmq, skb);
993 /* next retransmit attempt */
994 if (link_is_bc_sndlink(l))
995 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
996 __skb_queue_tail(xmitq, _skb);
997 TIPC_SKB_CB(skb)->ackers = l->ackers;
998 l->rcv_unacked = 0;
999 l->stats.sent_pkts++;
1000 seqno++;
1001 continue;
1002 }
1003 tskb = &l->backlog[imp].target_bskb;
1004 if (tipc_msg_bundle(*tskb, hdr, mtu)) {
1005 kfree_skb(__skb_dequeue(list));
1006 l->stats.sent_bundled++;
1007 continue;
1008 }
1009 if (tipc_msg_make_bundle(tskb, hdr, mtu, l->addr)) {
1010 kfree_skb(__skb_dequeue(list));
1011 __skb_queue_tail(backlogq, *tskb);
1012 l->backlog[imp].len++;
1013 l->stats.sent_bundled++;
1014 l->stats.sent_bundles++;
1015 continue;
1016 }
1017 l->backlog[imp].target_bskb = NULL;
1018 l->backlog[imp].len += skb_queue_len(list);
1019 skb_queue_splice_tail_init(list, backlogq);
1020 }
1021 l->snd_nxt = seqno;
1022 return rc;
1023}
1024
1025static void tipc_link_advance_backlog(struct tipc_link *l,
1026 struct sk_buff_head *xmitq)
1027{
1028 struct sk_buff *skb, *_skb;
1029 struct tipc_msg *hdr;
1030 u16 seqno = l->snd_nxt;
1031 u16 ack = l->rcv_nxt - 1;
1032 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1033 u32 imp;
1034
1035 while (skb_queue_len(&l->transmq) < l->window) {
1036 skb = skb_peek(&l->backlogq);
1037 if (!skb)
1038 break;
1039 _skb = skb_clone(skb, GFP_ATOMIC);
1040 if (!_skb)
1041 break;
1042 __skb_dequeue(&l->backlogq);
1043 hdr = buf_msg(skb);
1044 imp = msg_importance(hdr);
1045 l->backlog[imp].len--;
1046 if (unlikely(skb == l->backlog[imp].target_bskb))
1047 l->backlog[imp].target_bskb = NULL;
1048 __skb_queue_tail(&l->transmq, skb);
1049 /* next retransmit attempt */
1050 if (link_is_bc_sndlink(l))
1051 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
1052
1053 __skb_queue_tail(xmitq, _skb);
1054 TIPC_SKB_CB(skb)->ackers = l->ackers;
1055 msg_set_seqno(hdr, seqno);
1056 msg_set_ack(hdr, ack);
1057 msg_set_bcast_ack(hdr, bc_ack);
1058 l->rcv_unacked = 0;
1059 l->stats.sent_pkts++;
1060 seqno++;
1061 }
1062 l->snd_nxt = seqno;
1063}
1064
1065/**
1066 * link_retransmit_failure() - Detect repeated retransmit failures
1067 * @l: tipc link sender
1068 * @r: tipc link receiver (= l in case of unicast)
1069 * @rc: returned code
1070 *
1071 * Return: true if the repeated retransmit failures happens, otherwise
1072 * false
1073 */
1074static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1075 int *rc)
1076{
1077 struct sk_buff *skb = skb_peek(&l->transmq);
1078 struct tipc_msg *hdr;
1079
1080 if (!skb)
1081 return false;
1082
1083 if (!TIPC_SKB_CB(skb)->retr_cnt)
1084 return false;
1085
1086 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1087 msecs_to_jiffies(r->tolerance)))
1088 return false;
1089
1090 hdr = buf_msg(skb);
1091 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1092 return false;
1093
1094 pr_warn("Retransmission failure on link <%s>\n", l->name);
1095 link_print(l, "State of link ");
1096 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1097 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1098 pr_info("sqno %u, prev: %x, dest: %x\n",
1099 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1100 pr_info("retr_stamp %d, retr_cnt %d\n",
1101 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1102 TIPC_SKB_CB(skb)->retr_cnt);
1103
1104 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1105 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1106 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1107
1108 if (link_is_bc_sndlink(l)) {
1109 r->state = LINK_RESET;
1110 *rc = TIPC_LINK_DOWN_EVT;
1111 } else {
1112 *rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1113 }
1114
1115 return true;
1116}
1117
1118/* tipc_link_bc_retrans() - retransmit zero or more packets
1119 * @l: the link to transmit on
1120 * @r: the receiving link ordering the retransmit. Same as l if unicast
1121 * @from: retransmit from (inclusive) this sequence number
1122 * @to: retransmit to (inclusive) this sequence number
1123 * xmitq: queue for accumulating the retransmitted packets
1124 */
1125static int tipc_link_bc_retrans(struct tipc_link *l, struct tipc_link *r,
1126 u16 from, u16 to, struct sk_buff_head *xmitq)
1127{
1128 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
1129 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1130 u16 ack = l->rcv_nxt - 1;
1131 struct tipc_msg *hdr;
1132 int rc = 0;
1133
1134 if (!skb)
1135 return 0;
1136 if (less(to, from))
1137 return 0;
1138
1139 trace_tipc_link_retrans(r, from, to, &l->transmq);
1140
1141 if (link_retransmit_failure(l, r, &rc))
1142 return rc;
1143
1144 skb_queue_walk(&l->transmq, skb) {
1145 hdr = buf_msg(skb);
1146 if (less(msg_seqno(hdr), from))
1147 continue;
1148 if (more(msg_seqno(hdr), to))
1149 break;
1150
1151 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1152 continue;
1153 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
1154 _skb = __pskb_copy(skb, LL_MAX_HEADER + MIN_H_SIZE, GFP_ATOMIC);
1155 if (!_skb)
1156 return 0;
1157 hdr = buf_msg(_skb);
1158 msg_set_ack(hdr, ack);
1159 msg_set_bcast_ack(hdr, bc_ack);
1160 _skb->priority = TC_PRIO_CONTROL;
1161 __skb_queue_tail(xmitq, _skb);
1162 l->stats.retransmitted++;
1163
1164 /* Increase actual retrans counter & mark first time */
1165 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1166 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1167 }
1168 return 0;
1169}
1170
1171/* tipc_data_input - deliver data and name distr msgs to upper layer
1172 *
1173 * Consumes buffer if message is of right type
1174 * Node lock must be held
1175 */
1176static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1177 struct sk_buff_head *inputq)
1178{
1179 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1180 struct tipc_msg *hdr = buf_msg(skb);
1181
1182 switch (msg_user(hdr)) {
1183 case TIPC_LOW_IMPORTANCE:
1184 case TIPC_MEDIUM_IMPORTANCE:
1185 case TIPC_HIGH_IMPORTANCE:
1186 case TIPC_CRITICAL_IMPORTANCE:
1187 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1188 skb_queue_tail(mc_inputq, skb);
1189 return true;
1190 }
1191 /* fall through */
1192 case CONN_MANAGER:
1193 skb_queue_tail(inputq, skb);
1194 return true;
1195 case GROUP_PROTOCOL:
1196 skb_queue_tail(mc_inputq, skb);
1197 return true;
1198 case NAME_DISTRIBUTOR:
1199 l->bc_rcvlink->state = LINK_ESTABLISHED;
1200 skb_queue_tail(l->namedq, skb);
1201 return true;
1202 case MSG_BUNDLER:
1203 case TUNNEL_PROTOCOL:
1204 case MSG_FRAGMENTER:
1205 case BCAST_PROTOCOL:
1206 return false;
1207 default:
1208 pr_warn("Dropping received illegal msg type\n");
1209 kfree_skb(skb);
1210 return true;
1211 };
1212}
1213
1214/* tipc_link_input - process packet that has passed link protocol check
1215 *
1216 * Consumes buffer
1217 */
1218static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1219 struct sk_buff_head *inputq,
1220 struct sk_buff **reasm_skb)
1221{
1222 struct tipc_msg *hdr = buf_msg(skb);
1223 struct sk_buff *iskb;
1224 struct sk_buff_head tmpq;
1225 int usr = msg_user(hdr);
1226 int pos = 0;
1227
1228 if (usr == MSG_BUNDLER) {
1229 skb_queue_head_init(&tmpq);
1230 l->stats.recv_bundles++;
1231 l->stats.recv_bundled += msg_msgcnt(hdr);
1232 while (tipc_msg_extract(skb, &iskb, &pos))
1233 tipc_data_input(l, iskb, &tmpq);
1234 tipc_skb_queue_splice_tail(&tmpq, inputq);
1235 return 0;
1236 } else if (usr == MSG_FRAGMENTER) {
1237 l->stats.recv_fragments++;
1238 if (tipc_buf_append(reasm_skb, &skb)) {
1239 l->stats.recv_fragmented++;
1240 tipc_data_input(l, skb, inputq);
1241 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1242 pr_warn_ratelimited("Unable to build fragment list\n");
1243 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1244 }
1245 return 0;
1246 } else if (usr == BCAST_PROTOCOL) {
1247 tipc_bcast_lock(l->net);
1248 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1249 tipc_bcast_unlock(l->net);
1250 }
1251
1252 kfree_skb(skb);
1253 return 0;
1254}
1255
1256/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1257 * inner message along with the ones in the old link's
1258 * deferdq
1259 * @l: tunnel link
1260 * @skb: TUNNEL_PROTOCOL message
1261 * @inputq: queue to put messages ready for delivery
1262 */
1263static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1264 struct sk_buff_head *inputq)
1265{
1266 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1267 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1268 struct sk_buff_head *fdefq = &l->failover_deferdq;
1269 struct tipc_msg *hdr = buf_msg(skb);
1270 struct sk_buff *iskb;
1271 int ipos = 0;
1272 int rc = 0;
1273 u16 seqno;
1274
1275 if (msg_type(hdr) == SYNCH_MSG) {
1276 kfree_skb(skb);
1277 return 0;
1278 }
1279
1280 /* Not a fragment? */
1281 if (likely(!msg_nof_fragms(hdr))) {
1282 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1283 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1284 skb_queue_len(fdefq));
1285 return 0;
1286 }
1287 kfree_skb(skb);
1288 } else {
1289 /* Set fragment type for buf_append */
1290 if (msg_fragm_no(hdr) == 1)
1291 msg_set_type(hdr, FIRST_FRAGMENT);
1292 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1293 msg_set_type(hdr, FRAGMENT);
1294 else
1295 msg_set_type(hdr, LAST_FRAGMENT);
1296
1297 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1298 /* Successful but non-complete reassembly? */
1299 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1300 return 0;
1301 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1302 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1303 }
1304 iskb = skb;
1305 }
1306
1307 do {
1308 seqno = buf_seqno(iskb);
1309 if (unlikely(less(seqno, l->drop_point))) {
1310 kfree_skb(iskb);
1311 continue;
1312 }
1313 if (unlikely(seqno != l->drop_point)) {
1314 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1315 continue;
1316 }
1317
1318 l->drop_point++;
1319 if (!tipc_data_input(l, iskb, inputq))
1320 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1321 if (unlikely(rc))
1322 break;
1323 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1324
1325 return rc;
1326}
1327
1328static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1329{
1330 bool released = false;
1331 struct sk_buff *skb, *tmp;
1332
1333 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1334 if (more(buf_seqno(skb), acked))
1335 break;
1336 __skb_unlink(skb, &l->transmq);
1337 kfree_skb(skb);
1338 released = true;
1339 }
1340 return released;
1341}
1342
1343/* tipc_build_gap_ack_blks - build Gap ACK blocks
1344 * @l: tipc link that data have come with gaps in sequence if any
1345 * @data: data buffer to store the Gap ACK blocks after built
1346 *
1347 * returns the actual allocated memory size
1348 */
1349static u16 tipc_build_gap_ack_blks(struct tipc_link *l, void *data)
1350{
1351 struct sk_buff *skb = skb_peek(&l->deferdq);
1352 struct tipc_gap_ack_blks *ga = data;
1353 u16 len, expect, seqno = 0;
1354 u8 n = 0;
1355
1356 if (!skb)
1357 goto exit;
1358
1359 expect = buf_seqno(skb);
1360 skb_queue_walk(&l->deferdq, skb) {
1361 seqno = buf_seqno(skb);
1362 if (unlikely(more(seqno, expect))) {
1363 ga->gacks[n].ack = htons(expect - 1);
1364 ga->gacks[n].gap = htons(seqno - expect);
1365 if (++n >= MAX_GAP_ACK_BLKS) {
1366 pr_info_ratelimited("Too few Gap ACK blocks!\n");
1367 goto exit;
1368 }
1369 } else if (unlikely(less(seqno, expect))) {
1370 pr_warn("Unexpected skb in deferdq!\n");
1371 continue;
1372 }
1373 expect = seqno + 1;
1374 }
1375
1376 /* last block */
1377 ga->gacks[n].ack = htons(seqno);
1378 ga->gacks[n].gap = 0;
1379 n++;
1380
1381exit:
1382 len = tipc_gap_ack_blks_sz(n);
1383 ga->len = htons(len);
1384 ga->gack_cnt = n;
1385 return len;
1386}
1387
1388/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1389 * acked packets, also doing retransmissions if
1390 * gaps found
1391 * @l: tipc link with transmq queue to be advanced
1392 * @acked: seqno of last packet acked by peer without any gaps before
1393 * @gap: # of gap packets
1394 * @ga: buffer pointer to Gap ACK blocks from peer
1395 * @xmitq: queue for accumulating the retransmitted packets if any
1396 *
1397 * In case of a repeated retransmit failures, the call will return shortly
1398 * with a returned code (e.g. TIPC_LINK_DOWN_EVT)
1399 */
1400static int tipc_link_advance_transmq(struct tipc_link *l, u16 acked, u16 gap,
1401 struct tipc_gap_ack_blks *ga,
1402 struct sk_buff_head *xmitq)
1403{
1404 struct sk_buff *skb, *_skb, *tmp;
1405 struct tipc_msg *hdr;
1406 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1407 u16 ack = l->rcv_nxt - 1;
1408 bool passed = false;
1409 u16 seqno, n = 0;
1410 int rc = 0;
1411
1412 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1413 seqno = buf_seqno(skb);
1414
1415next_gap_ack:
1416 if (less_eq(seqno, acked)) {
1417 /* release skb */
1418 __skb_unlink(skb, &l->transmq);
1419 kfree_skb(skb);
1420 } else if (less_eq(seqno, acked + gap)) {
1421 /* First, check if repeated retrans failures occurs? */
1422 if (!passed && link_retransmit_failure(l, l, &rc))
1423 return rc;
1424 passed = true;
1425
1426 /* retransmit skb if unrestricted*/
1427 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1428 continue;
1429 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
1430 _skb = __pskb_copy(skb, LL_MAX_HEADER + MIN_H_SIZE,
1431 GFP_ATOMIC);
1432 if (!_skb)
1433 continue;
1434 hdr = buf_msg(_skb);
1435 msg_set_ack(hdr, ack);
1436 msg_set_bcast_ack(hdr, bc_ack);
1437 _skb->priority = TC_PRIO_CONTROL;
1438 __skb_queue_tail(xmitq, _skb);
1439 l->stats.retransmitted++;
1440
1441 /* Increase actual retrans counter & mark first time */
1442 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1443 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1444 } else {
1445 /* retry with Gap ACK blocks if any */
1446 if (!ga || n >= ga->gack_cnt)
1447 break;
1448 acked = ntohs(ga->gacks[n].ack);
1449 gap = ntohs(ga->gacks[n].gap);
1450 n++;
1451 goto next_gap_ack;
1452 }
1453 }
1454
1455 return 0;
1456}
1457
1458/* tipc_link_build_state_msg: prepare link state message for transmission
1459 *
1460 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1461 * risk of ack storms towards the sender
1462 */
1463int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1464{
1465 if (!l)
1466 return 0;
1467
1468 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1469 if (link_is_bc_rcvlink(l)) {
1470 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1471 return 0;
1472 l->rcv_unacked = 0;
1473
1474 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1475 l->snd_nxt = l->rcv_nxt;
1476 return TIPC_LINK_SND_STATE;
1477 }
1478
1479 /* Unicast ACK */
1480 l->rcv_unacked = 0;
1481 l->stats.sent_acks++;
1482 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1483 return 0;
1484}
1485
1486/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1487 */
1488void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1489{
1490 int mtyp = RESET_MSG;
1491 struct sk_buff *skb;
1492
1493 if (l->state == LINK_ESTABLISHING)
1494 mtyp = ACTIVATE_MSG;
1495
1496 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1497
1498 /* Inform peer that this endpoint is going down if applicable */
1499 skb = skb_peek_tail(xmitq);
1500 if (skb && (l->state == LINK_RESET))
1501 msg_set_peer_stopping(buf_msg(skb), 1);
1502}
1503
1504/* tipc_link_build_nack_msg: prepare link nack message for transmission
1505 * Note that sending of broadcast NACK is coordinated among nodes, to
1506 * reduce the risk of NACK storms towards the sender
1507 */
1508static int tipc_link_build_nack_msg(struct tipc_link *l,
1509 struct sk_buff_head *xmitq)
1510{
1511 u32 def_cnt = ++l->stats.deferred_recv;
1512 u32 defq_len = skb_queue_len(&l->deferdq);
1513 int match1, match2;
1514
1515 if (link_is_bc_rcvlink(l)) {
1516 match1 = def_cnt & 0xf;
1517 match2 = tipc_own_addr(l->net) & 0xf;
1518 if (match1 == match2)
1519 return TIPC_LINK_SND_STATE;
1520 return 0;
1521 }
1522
1523 if (defq_len >= 3 && !((defq_len - 3) % 16))
1524 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1525 return 0;
1526}
1527
1528/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1529 * @l: the link that should handle the message
1530 * @skb: TIPC packet
1531 * @xmitq: queue to place packets to be sent after this call
1532 */
1533int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1534 struct sk_buff_head *xmitq)
1535{
1536 struct sk_buff_head *defq = &l->deferdq;
1537 struct tipc_msg *hdr = buf_msg(skb);
1538 u16 seqno, rcv_nxt, win_lim;
1539 int rc = 0;
1540
1541 /* Verify and update link state */
1542 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1543 return tipc_link_proto_rcv(l, skb, xmitq);
1544
1545 /* Don't send probe at next timeout expiration */
1546 l->silent_intv_cnt = 0;
1547
1548 do {
1549 hdr = buf_msg(skb);
1550 seqno = msg_seqno(hdr);
1551 rcv_nxt = l->rcv_nxt;
1552 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1553
1554 if (unlikely(!link_is_up(l))) {
1555 if (l->state == LINK_ESTABLISHING)
1556 rc = TIPC_LINK_UP_EVT;
1557 goto drop;
1558 }
1559
1560 /* Drop if outside receive window */
1561 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1562 l->stats.duplicates++;
1563 goto drop;
1564 }
1565
1566 /* Forward queues and wake up waiting users */
1567 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1568 tipc_link_advance_backlog(l, xmitq);
1569 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1570 link_prepare_wakeup(l);
1571 }
1572
1573 /* Defer delivery if sequence gap */
1574 if (unlikely(seqno != rcv_nxt)) {
1575 __tipc_skb_queue_sorted(defq, seqno, skb);
1576 rc |= tipc_link_build_nack_msg(l, xmitq);
1577 break;
1578 }
1579
1580 /* Deliver packet */
1581 l->rcv_nxt++;
1582 l->stats.recv_pkts++;
1583
1584 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1585 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1586 else if (!tipc_data_input(l, skb, l->inputq))
1587 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1588 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1589 rc |= tipc_link_build_state_msg(l, xmitq);
1590 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1591 break;
1592 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1593
1594 return rc;
1595drop:
1596 kfree_skb(skb);
1597 return rc;
1598}
1599
1600static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1601 bool probe_reply, u16 rcvgap,
1602 int tolerance, int priority,
1603 struct sk_buff_head *xmitq)
1604{
1605 struct tipc_link *bcl = l->bc_rcvlink;
1606 struct sk_buff *skb;
1607 struct tipc_msg *hdr;
1608 struct sk_buff_head *dfq = &l->deferdq;
1609 bool node_up = link_is_up(bcl);
1610 struct tipc_mon_state *mstate = &l->mon_state;
1611 int dlen = 0;
1612 void *data;
1613 u16 glen = 0;
1614
1615 /* Don't send protocol message during reset or link failover */
1616 if (tipc_link_is_blocked(l))
1617 return;
1618
1619 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1620 return;
1621
1622 if (!skb_queue_empty(dfq))
1623 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1624
1625 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1626 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1627 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1628 if (!skb)
1629 return;
1630
1631 hdr = buf_msg(skb);
1632 data = msg_data(hdr);
1633 msg_set_session(hdr, l->session);
1634 msg_set_bearer_id(hdr, l->bearer_id);
1635 msg_set_net_plane(hdr, l->net_plane);
1636 msg_set_next_sent(hdr, l->snd_nxt);
1637 msg_set_ack(hdr, l->rcv_nxt - 1);
1638 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1639 msg_set_bc_ack_invalid(hdr, !node_up);
1640 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1641 msg_set_link_tolerance(hdr, tolerance);
1642 msg_set_linkprio(hdr, priority);
1643 msg_set_redundant_link(hdr, node_up);
1644 msg_set_seq_gap(hdr, 0);
1645 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1646
1647 if (mtyp == STATE_MSG) {
1648 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1649 msg_set_seqno(hdr, l->snd_nxt_state++);
1650 msg_set_seq_gap(hdr, rcvgap);
1651 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1652 msg_set_probe(hdr, probe);
1653 msg_set_is_keepalive(hdr, probe || probe_reply);
1654 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1655 glen = tipc_build_gap_ack_blks(l, data);
1656 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1657 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1658 skb_trim(skb, INT_H_SIZE + glen + dlen);
1659 l->stats.sent_states++;
1660 l->rcv_unacked = 0;
1661 } else {
1662 /* RESET_MSG or ACTIVATE_MSG */
1663 if (mtyp == ACTIVATE_MSG) {
1664 msg_set_dest_session_valid(hdr, 1);
1665 msg_set_dest_session(hdr, l->peer_session);
1666 }
1667 msg_set_max_pkt(hdr, l->advertised_mtu);
1668 strcpy(data, l->if_name);
1669 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1670 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1671 }
1672 if (probe)
1673 l->stats.sent_probes++;
1674 if (rcvgap)
1675 l->stats.sent_nacks++;
1676 skb->priority = TC_PRIO_CONTROL;
1677 __skb_queue_tail(xmitq, skb);
1678 trace_tipc_proto_build(skb, false, l->name);
1679}
1680
1681void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1682 struct sk_buff_head *xmitq)
1683{
1684 u32 onode = tipc_own_addr(l->net);
1685 struct tipc_msg *hdr, *ihdr;
1686 struct sk_buff_head tnlq;
1687 struct sk_buff *skb;
1688 u32 dnode = l->addr;
1689
1690 __skb_queue_head_init(&tnlq);
1691 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1692 INT_H_SIZE, BASIC_H_SIZE,
1693 dnode, onode, 0, 0, 0);
1694 if (!skb) {
1695 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1696 return;
1697 }
1698
1699 hdr = buf_msg(skb);
1700 msg_set_msgcnt(hdr, 1);
1701 msg_set_bearer_id(hdr, l->peer_bearer_id);
1702
1703 ihdr = (struct tipc_msg *)msg_data(hdr);
1704 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1705 BASIC_H_SIZE, dnode);
1706 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1707 __skb_queue_tail(&tnlq, skb);
1708 tipc_link_xmit(l, &tnlq, xmitq);
1709}
1710
1711/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1712 * with contents of the link's transmit and backlog queues.
1713 */
1714void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1715 int mtyp, struct sk_buff_head *xmitq)
1716{
1717 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1718 struct sk_buff *skb, *tnlskb;
1719 struct tipc_msg *hdr, tnlhdr;
1720 struct sk_buff_head *queue = &l->transmq;
1721 struct sk_buff_head tmpxq, tnlq, frags;
1722 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1723 bool pktcnt_need_update = false;
1724 u16 syncpt;
1725 int rc;
1726
1727 if (!tnl)
1728 return;
1729
1730 __skb_queue_head_init(&tnlq);
1731 __skb_queue_head_init(&tmpxq);
1732 __skb_queue_head_init(&frags);
1733
1734 /* At least one packet required for safe algorithm => add dummy */
1735 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1736 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1737 0, 0, TIPC_ERR_NO_PORT);
1738 if (!skb) {
1739 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1740 return;
1741 }
1742 __skb_queue_tail(&tnlq, skb);
1743 tipc_link_xmit(l, &tnlq, &tmpxq);
1744 __skb_queue_purge(&tmpxq);
1745
1746 /* Link Synching:
1747 * From now on, send only one single ("dummy") SYNCH message
1748 * to peer. The SYNCH message does not contain any data, just
1749 * a header conveying the synch point to the peer.
1750 */
1751 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1752 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1753 INT_H_SIZE, 0, l->addr,
1754 tipc_own_addr(l->net),
1755 0, 0, 0);
1756 if (!tnlskb) {
1757 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1758 link_co_err);
1759 return;
1760 }
1761
1762 hdr = buf_msg(tnlskb);
1763 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
1764 msg_set_syncpt(hdr, syncpt);
1765 msg_set_bearer_id(hdr, l->peer_bearer_id);
1766 __skb_queue_tail(&tnlq, tnlskb);
1767 tipc_link_xmit(tnl, &tnlq, xmitq);
1768 return;
1769 }
1770
1771 /* Initialize reusable tunnel packet header */
1772 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1773 mtyp, INT_H_SIZE, l->addr);
1774 if (mtyp == SYNCH_MSG)
1775 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
1776 else
1777 pktcnt = skb_queue_len(&l->transmq);
1778 pktcnt += skb_queue_len(&l->backlogq);
1779 msg_set_msgcnt(&tnlhdr, pktcnt);
1780 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1781tnl:
1782 /* Wrap each packet into a tunnel packet */
1783 skb_queue_walk(queue, skb) {
1784 hdr = buf_msg(skb);
1785 if (queue == &l->backlogq)
1786 msg_set_seqno(hdr, seqno++);
1787 pktlen = msg_size(hdr);
1788
1789 /* Tunnel link MTU is not large enough? This could be
1790 * due to:
1791 * 1) Link MTU has just changed or set differently;
1792 * 2) Or FAILOVER on the top of a SYNCH message
1793 *
1794 * The 2nd case should not happen if peer supports
1795 * TIPC_TUNNEL_ENHANCED
1796 */
1797 if (pktlen > tnl->mtu - INT_H_SIZE) {
1798 if (mtyp == FAILOVER_MSG &&
1799 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1800 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
1801 &frags);
1802 if (rc) {
1803 pr_warn("%sunable to frag msg: rc %d\n",
1804 link_co_err, rc);
1805 return;
1806 }
1807 pktcnt += skb_queue_len(&frags) - 1;
1808 pktcnt_need_update = true;
1809 skb_queue_splice_tail_init(&frags, &tnlq);
1810 continue;
1811 }
1812 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
1813 * => Just warn it and return!
1814 */
1815 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
1816 link_co_err, msg_user(hdr),
1817 msg_type(hdr), msg_size(hdr));
1818 return;
1819 }
1820
1821 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1822 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
1823 if (!tnlskb) {
1824 pr_warn("%sunable to send packet\n", link_co_err);
1825 return;
1826 }
1827 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1828 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1829 __skb_queue_tail(&tnlq, tnlskb);
1830 }
1831 if (queue != &l->backlogq) {
1832 queue = &l->backlogq;
1833 goto tnl;
1834 }
1835
1836 if (pktcnt_need_update)
1837 skb_queue_walk(&tnlq, skb) {
1838 hdr = buf_msg(skb);
1839 msg_set_msgcnt(hdr, pktcnt);
1840 }
1841
1842 tipc_link_xmit(tnl, &tnlq, xmitq);
1843
1844 if (mtyp == FAILOVER_MSG) {
1845 tnl->drop_point = l->rcv_nxt;
1846 tnl->failover_reasm_skb = l->reasm_buf;
1847 l->reasm_buf = NULL;
1848
1849 /* Failover the link's deferdq */
1850 if (unlikely(!skb_queue_empty(fdefq))) {
1851 pr_warn("Link failover deferdq not empty: %d!\n",
1852 skb_queue_len(fdefq));
1853 __skb_queue_purge(fdefq);
1854 }
1855 skb_queue_splice_init(&l->deferdq, fdefq);
1856 }
1857}
1858
1859/**
1860 * tipc_link_failover_prepare() - prepare tnl for link failover
1861 *
1862 * This is a special version of the precursor - tipc_link_tnl_prepare(),
1863 * see the tipc_node_link_failover() for details
1864 *
1865 * @l: failover link
1866 * @tnl: tunnel link
1867 * @xmitq: queue for messages to be xmited
1868 */
1869void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
1870 struct sk_buff_head *xmitq)
1871{
1872 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1873
1874 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
1875
1876 /* This failover link enpoint was never established before,
1877 * so it has not received anything from peer.
1878 * Otherwise, it must be a normal failover situation or the
1879 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
1880 * would have to start over from scratch instead.
1881 */
1882 tnl->drop_point = 1;
1883 tnl->failover_reasm_skb = NULL;
1884
1885 /* Initiate the link's failover deferdq */
1886 if (unlikely(!skb_queue_empty(fdefq))) {
1887 pr_warn("Link failover deferdq not empty: %d!\n",
1888 skb_queue_len(fdefq));
1889 __skb_queue_purge(fdefq);
1890 }
1891}
1892
1893/* tipc_link_validate_msg(): validate message against current link state
1894 * Returns true if message should be accepted, otherwise false
1895 */
1896bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
1897{
1898 u16 curr_session = l->peer_session;
1899 u16 session = msg_session(hdr);
1900 int mtyp = msg_type(hdr);
1901
1902 if (msg_user(hdr) != LINK_PROTOCOL)
1903 return true;
1904
1905 switch (mtyp) {
1906 case RESET_MSG:
1907 if (!l->in_session)
1908 return true;
1909 /* Accept only RESET with new session number */
1910 return more(session, curr_session);
1911 case ACTIVATE_MSG:
1912 if (!l->in_session)
1913 return true;
1914 /* Accept only ACTIVATE with new or current session number */
1915 return !less(session, curr_session);
1916 case STATE_MSG:
1917 /* Accept only STATE with current session number */
1918 if (!l->in_session)
1919 return false;
1920 if (session != curr_session)
1921 return false;
1922 /* Extra sanity check */
1923 if (!link_is_up(l) && msg_ack(hdr))
1924 return false;
1925 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
1926 return true;
1927 /* Accept only STATE with new sequence number */
1928 return !less(msg_seqno(hdr), l->rcv_nxt_state);
1929 default:
1930 return false;
1931 }
1932}
1933
1934/* tipc_link_proto_rcv(): receive link level protocol message :
1935 * Note that network plane id propagates through the network, and may
1936 * change at any time. The node with lowest numerical id determines
1937 * network plane
1938 */
1939static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1940 struct sk_buff_head *xmitq)
1941{
1942 struct tipc_msg *hdr = buf_msg(skb);
1943 struct tipc_gap_ack_blks *ga = NULL;
1944 u16 rcvgap = 0;
1945 u16 ack = msg_ack(hdr);
1946 u16 gap = msg_seq_gap(hdr);
1947 u16 peers_snd_nxt = msg_next_sent(hdr);
1948 u16 peers_tol = msg_link_tolerance(hdr);
1949 u16 peers_prio = msg_linkprio(hdr);
1950 u16 rcv_nxt = l->rcv_nxt;
1951 u16 dlen = msg_data_sz(hdr);
1952 int mtyp = msg_type(hdr);
1953 bool reply = msg_probe(hdr);
1954 u16 glen = 0;
1955 void *data;
1956 char *if_name;
1957 int rc = 0;
1958
1959 trace_tipc_proto_rcv(skb, false, l->name);
1960 if (tipc_link_is_blocked(l) || !xmitq)
1961 goto exit;
1962
1963 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1964 l->net_plane = msg_net_plane(hdr);
1965
1966 skb_linearize(skb);
1967 hdr = buf_msg(skb);
1968 data = msg_data(hdr);
1969
1970 if (!tipc_link_validate_msg(l, hdr)) {
1971 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
1972 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
1973 goto exit;
1974 }
1975
1976 switch (mtyp) {
1977 case RESET_MSG:
1978 case ACTIVATE_MSG:
1979 /* Complete own link name with peer's interface name */
1980 if_name = strrchr(l->name, ':') + 1;
1981 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1982 break;
1983 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1984 break;
1985 strncpy(if_name, data, TIPC_MAX_IF_NAME);
1986
1987 /* Update own tolerance if peer indicates a non-zero value */
1988 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
1989 l->tolerance = peers_tol;
1990 l->bc_rcvlink->tolerance = peers_tol;
1991 }
1992 /* Update own priority if peer's priority is higher */
1993 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1994 l->priority = peers_prio;
1995
1996 /* If peer is going down we want full re-establish cycle */
1997 if (msg_peer_stopping(hdr)) {
1998 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1999 break;
2000 }
2001
2002 /* If this endpoint was re-created while peer was ESTABLISHING
2003 * it doesn't know current session number. Force re-synch.
2004 */
2005 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2006 l->session != msg_dest_session(hdr)) {
2007 if (less(l->session, msg_dest_session(hdr)))
2008 l->session = msg_dest_session(hdr) + 1;
2009 break;
2010 }
2011
2012 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2013 if (mtyp == RESET_MSG || !link_is_up(l))
2014 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2015
2016 /* ACTIVATE_MSG takes up link if it was already locally reset */
2017 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2018 rc = TIPC_LINK_UP_EVT;
2019
2020 l->peer_session = msg_session(hdr);
2021 l->in_session = true;
2022 l->peer_bearer_id = msg_bearer_id(hdr);
2023 if (l->mtu > msg_max_pkt(hdr))
2024 l->mtu = msg_max_pkt(hdr);
2025 break;
2026
2027 case STATE_MSG:
2028 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2029
2030 /* Update own tolerance if peer indicates a non-zero value */
2031 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2032 l->tolerance = peers_tol;
2033 l->bc_rcvlink->tolerance = peers_tol;
2034 }
2035 /* Update own prio if peer indicates a different value */
2036 if ((peers_prio != l->priority) &&
2037 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2038 l->priority = peers_prio;
2039 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2040 }
2041
2042 l->silent_intv_cnt = 0;
2043 l->stats.recv_states++;
2044 if (msg_probe(hdr))
2045 l->stats.recv_probes++;
2046
2047 if (!link_is_up(l)) {
2048 if (l->state == LINK_ESTABLISHING)
2049 rc = TIPC_LINK_UP_EVT;
2050 break;
2051 }
2052
2053 /* Receive Gap ACK blocks from peer if any */
2054 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
2055 ga = (struct tipc_gap_ack_blks *)data;
2056 glen = ntohs(ga->len);
2057 /* sanity check: if failed, ignore Gap ACK blocks */
2058 if (glen != tipc_gap_ack_blks_sz(ga->gack_cnt))
2059 ga = NULL;
2060 }
2061
2062 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2063 &l->mon_state, l->bearer_id);
2064
2065 /* Send NACK if peer has sent pkts we haven't received yet */
2066 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
2067 rcvgap = peers_snd_nxt - l->rcv_nxt;
2068 if (rcvgap || reply)
2069 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2070 rcvgap, 0, 0, xmitq);
2071
2072 rc |= tipc_link_advance_transmq(l, ack, gap, ga, xmitq);
2073
2074 /* If NACK, retransmit will now start at right position */
2075 if (gap)
2076 l->stats.recv_nacks++;
2077
2078 tipc_link_advance_backlog(l, xmitq);
2079 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2080 link_prepare_wakeup(l);
2081 }
2082exit:
2083 kfree_skb(skb);
2084 return rc;
2085}
2086
2087/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2088 */
2089static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2090 u16 peers_snd_nxt,
2091 struct sk_buff_head *xmitq)
2092{
2093 struct sk_buff *skb;
2094 struct tipc_msg *hdr;
2095 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2096 u16 ack = l->rcv_nxt - 1;
2097 u16 gap_to = peers_snd_nxt - 1;
2098
2099 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2100 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2101 if (!skb)
2102 return false;
2103 hdr = buf_msg(skb);
2104 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2105 msg_set_bcast_ack(hdr, ack);
2106 msg_set_bcgap_after(hdr, ack);
2107 if (dfrd_skb)
2108 gap_to = buf_seqno(dfrd_skb) - 1;
2109 msg_set_bcgap_to(hdr, gap_to);
2110 msg_set_non_seq(hdr, bcast);
2111 __skb_queue_tail(xmitq, skb);
2112 return true;
2113}
2114
2115/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2116 *
2117 * Give a newly added peer node the sequence number where it should
2118 * start receiving and acking broadcast packets.
2119 */
2120static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2121 struct sk_buff_head *xmitq)
2122{
2123 struct sk_buff_head list;
2124
2125 __skb_queue_head_init(&list);
2126 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2127 return;
2128 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2129 tipc_link_xmit(l, &list, xmitq);
2130}
2131
2132/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2133 */
2134void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2135{
2136 int mtyp = msg_type(hdr);
2137 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2138
2139 if (link_is_up(l))
2140 return;
2141
2142 if (msg_user(hdr) == BCAST_PROTOCOL) {
2143 l->rcv_nxt = peers_snd_nxt;
2144 l->state = LINK_ESTABLISHED;
2145 return;
2146 }
2147
2148 if (l->peer_caps & TIPC_BCAST_SYNCH)
2149 return;
2150
2151 if (msg_peer_node_is_up(hdr))
2152 return;
2153
2154 /* Compatibility: accept older, less safe initial synch data */
2155 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2156 l->rcv_nxt = peers_snd_nxt;
2157}
2158
2159/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2160 */
2161int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2162 struct sk_buff_head *xmitq)
2163{
2164 struct tipc_link *snd_l = l->bc_sndlink;
2165 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2166 u16 from = msg_bcast_ack(hdr) + 1;
2167 u16 to = from + msg_bc_gap(hdr) - 1;
2168 int rc = 0;
2169
2170 if (!link_is_up(l))
2171 return rc;
2172
2173 if (!msg_peer_node_is_up(hdr))
2174 return rc;
2175
2176 /* Open when peer ackowledges our bcast init msg (pkt #1) */
2177 if (msg_ack(hdr))
2178 l->bc_peer_is_up = true;
2179
2180 if (!l->bc_peer_is_up)
2181 return rc;
2182
2183 l->stats.recv_nacks++;
2184
2185 /* Ignore if peers_snd_nxt goes beyond receive window */
2186 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2187 return rc;
2188
2189 rc = tipc_link_bc_retrans(snd_l, l, from, to, xmitq);
2190
2191 l->snd_nxt = peers_snd_nxt;
2192 if (link_bc_rcv_gap(l))
2193 rc |= TIPC_LINK_SND_STATE;
2194
2195 /* Return now if sender supports nack via STATE messages */
2196 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2197 return rc;
2198
2199 /* Otherwise, be backwards compatible */
2200
2201 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2202 l->nack_state = BC_NACK_SND_CONDITIONAL;
2203 return 0;
2204 }
2205
2206 /* Don't NACK if one was recently sent or peeked */
2207 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2208 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2209 return 0;
2210 }
2211
2212 /* Conditionally delay NACK sending until next synch rcv */
2213 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2214 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2215 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2216 return 0;
2217 }
2218
2219 /* Send NACK now but suppress next one */
2220 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2221 l->nack_state = BC_NACK_SND_SUPPRESS;
2222 return 0;
2223}
2224
2225void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
2226 struct sk_buff_head *xmitq)
2227{
2228 struct sk_buff *skb, *tmp;
2229 struct tipc_link *snd_l = l->bc_sndlink;
2230
2231 if (!link_is_up(l) || !l->bc_peer_is_up)
2232 return;
2233
2234 if (!more(acked, l->acked))
2235 return;
2236
2237 trace_tipc_link_bc_ack(l, l->acked, acked, &snd_l->transmq);
2238 /* Skip over packets peer has already acked */
2239 skb_queue_walk(&snd_l->transmq, skb) {
2240 if (more(buf_seqno(skb), l->acked))
2241 break;
2242 }
2243
2244 /* Update/release the packets peer is acking now */
2245 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
2246 if (more(buf_seqno(skb), acked))
2247 break;
2248 if (!--TIPC_SKB_CB(skb)->ackers) {
2249 __skb_unlink(skb, &snd_l->transmq);
2250 kfree_skb(skb);
2251 }
2252 }
2253 l->acked = acked;
2254 tipc_link_advance_backlog(snd_l, xmitq);
2255 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
2256 link_prepare_wakeup(snd_l);
2257}
2258
2259/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2260 * This function is here for backwards compatibility, since
2261 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2262 */
2263int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2264 struct sk_buff_head *xmitq)
2265{
2266 struct tipc_msg *hdr = buf_msg(skb);
2267 u32 dnode = msg_destnode(hdr);
2268 int mtyp = msg_type(hdr);
2269 u16 acked = msg_bcast_ack(hdr);
2270 u16 from = acked + 1;
2271 u16 to = msg_bcgap_to(hdr);
2272 u16 peers_snd_nxt = to + 1;
2273 int rc = 0;
2274
2275 kfree_skb(skb);
2276
2277 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2278 return 0;
2279
2280 if (mtyp != STATE_MSG)
2281 return 0;
2282
2283 if (dnode == tipc_own_addr(l->net)) {
2284 tipc_link_bc_ack_rcv(l, acked, xmitq);
2285 rc = tipc_link_bc_retrans(l->bc_sndlink, l, from, to, xmitq);
2286 l->stats.recv_nacks++;
2287 return rc;
2288 }
2289
2290 /* Msg for other node => suppress own NACK at next sync if applicable */
2291 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2292 l->nack_state = BC_NACK_SND_SUPPRESS;
2293
2294 return 0;
2295}
2296
2297void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
2298{
2299 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2300
2301 l->window = win;
2302 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win);
2303 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2);
2304 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3);
2305 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4);
2306 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2307}
2308
2309/**
2310 * link_reset_stats - reset link statistics
2311 * @l: pointer to link
2312 */
2313void tipc_link_reset_stats(struct tipc_link *l)
2314{
2315 memset(&l->stats, 0, sizeof(l->stats));
2316}
2317
2318static void link_print(struct tipc_link *l, const char *str)
2319{
2320 struct sk_buff *hskb = skb_peek(&l->transmq);
2321 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2322 u16 tail = l->snd_nxt - 1;
2323
2324 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2325 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2326 skb_queue_len(&l->transmq), head, tail,
2327 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2328}
2329
2330/* Parse and validate nested (link) properties valid for media, bearer and link
2331 */
2332int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2333{
2334 int err;
2335
2336 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2337 tipc_nl_prop_policy, NULL);
2338 if (err)
2339 return err;
2340
2341 if (props[TIPC_NLA_PROP_PRIO]) {
2342 u32 prio;
2343
2344 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2345 if (prio > TIPC_MAX_LINK_PRI)
2346 return -EINVAL;
2347 }
2348
2349 if (props[TIPC_NLA_PROP_TOL]) {
2350 u32 tol;
2351
2352 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2353 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2354 return -EINVAL;
2355 }
2356
2357 if (props[TIPC_NLA_PROP_WIN]) {
2358 u32 win;
2359
2360 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2361 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
2362 return -EINVAL;
2363 }
2364
2365 return 0;
2366}
2367
2368static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2369{
2370 int i;
2371 struct nlattr *stats;
2372
2373 struct nla_map {
2374 u32 key;
2375 u32 val;
2376 };
2377
2378 struct nla_map map[] = {
2379 {TIPC_NLA_STATS_RX_INFO, 0},
2380 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2381 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2382 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2383 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2384 {TIPC_NLA_STATS_TX_INFO, 0},
2385 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2386 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2387 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2388 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2389 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2390 s->msg_length_counts : 1},
2391 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2392 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2393 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2394 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2395 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2396 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2397 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2398 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2399 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2400 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2401 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2402 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2403 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2404 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2405 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2406 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2407 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2408 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2409 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2410 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2411 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2412 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2413 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2414 };
2415
2416 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2417 if (!stats)
2418 return -EMSGSIZE;
2419
2420 for (i = 0; i < ARRAY_SIZE(map); i++)
2421 if (nla_put_u32(skb, map[i].key, map[i].val))
2422 goto msg_full;
2423
2424 nla_nest_end(skb, stats);
2425
2426 return 0;
2427msg_full:
2428 nla_nest_cancel(skb, stats);
2429
2430 return -EMSGSIZE;
2431}
2432
2433/* Caller should hold appropriate locks to protect the link */
2434int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2435 struct tipc_link *link, int nlflags)
2436{
2437 u32 self = tipc_own_addr(net);
2438 struct nlattr *attrs;
2439 struct nlattr *prop;
2440 void *hdr;
2441 int err;
2442
2443 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2444 nlflags, TIPC_NL_LINK_GET);
2445 if (!hdr)
2446 return -EMSGSIZE;
2447
2448 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2449 if (!attrs)
2450 goto msg_full;
2451
2452 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2453 goto attr_msg_full;
2454 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2455 goto attr_msg_full;
2456 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2457 goto attr_msg_full;
2458 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2459 goto attr_msg_full;
2460 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2461 goto attr_msg_full;
2462
2463 if (tipc_link_is_up(link))
2464 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2465 goto attr_msg_full;
2466 if (link->active)
2467 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2468 goto attr_msg_full;
2469
2470 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2471 if (!prop)
2472 goto attr_msg_full;
2473 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2474 goto prop_msg_full;
2475 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2476 goto prop_msg_full;
2477 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2478 link->window))
2479 goto prop_msg_full;
2480 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2481 goto prop_msg_full;
2482 nla_nest_end(msg->skb, prop);
2483
2484 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2485 if (err)
2486 goto attr_msg_full;
2487
2488 nla_nest_end(msg->skb, attrs);
2489 genlmsg_end(msg->skb, hdr);
2490
2491 return 0;
2492
2493prop_msg_full:
2494 nla_nest_cancel(msg->skb, prop);
2495attr_msg_full:
2496 nla_nest_cancel(msg->skb, attrs);
2497msg_full:
2498 genlmsg_cancel(msg->skb, hdr);
2499
2500 return -EMSGSIZE;
2501}
2502
2503static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2504 struct tipc_stats *stats)
2505{
2506 int i;
2507 struct nlattr *nest;
2508
2509 struct nla_map {
2510 __u32 key;
2511 __u32 val;
2512 };
2513
2514 struct nla_map map[] = {
2515 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2516 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2517 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2518 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2519 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2520 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2521 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2522 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2523 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2524 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2525 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2526 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2527 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2528 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2529 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2530 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2531 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2532 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2533 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2534 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2535 };
2536
2537 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2538 if (!nest)
2539 return -EMSGSIZE;
2540
2541 for (i = 0; i < ARRAY_SIZE(map); i++)
2542 if (nla_put_u32(skb, map[i].key, map[i].val))
2543 goto msg_full;
2544
2545 nla_nest_end(skb, nest);
2546
2547 return 0;
2548msg_full:
2549 nla_nest_cancel(skb, nest);
2550
2551 return -EMSGSIZE;
2552}
2553
2554int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
2555{
2556 int err;
2557 void *hdr;
2558 struct nlattr *attrs;
2559 struct nlattr *prop;
2560 struct tipc_net *tn = net_generic(net, tipc_net_id);
2561 u32 bc_mode = tipc_bcast_get_broadcast_mode(net);
2562 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2563 struct tipc_link *bcl = tn->bcl;
2564
2565 if (!bcl)
2566 return 0;
2567
2568 tipc_bcast_lock(net);
2569
2570 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2571 NLM_F_MULTI, TIPC_NL_LINK_GET);
2572 if (!hdr) {
2573 tipc_bcast_unlock(net);
2574 return -EMSGSIZE;
2575 }
2576
2577 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2578 if (!attrs)
2579 goto msg_full;
2580
2581 /* The broadcast link is always up */
2582 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2583 goto attr_msg_full;
2584
2585 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2586 goto attr_msg_full;
2587 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2588 goto attr_msg_full;
2589 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2590 goto attr_msg_full;
2591 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2592 goto attr_msg_full;
2593
2594 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2595 if (!prop)
2596 goto attr_msg_full;
2597 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
2598 goto prop_msg_full;
2599 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2600 goto prop_msg_full;
2601 if (bc_mode & BCLINK_MODE_SEL)
2602 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2603 bc_ratio))
2604 goto prop_msg_full;
2605 nla_nest_end(msg->skb, prop);
2606
2607 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2608 if (err)
2609 goto attr_msg_full;
2610
2611 tipc_bcast_unlock(net);
2612 nla_nest_end(msg->skb, attrs);
2613 genlmsg_end(msg->skb, hdr);
2614
2615 return 0;
2616
2617prop_msg_full:
2618 nla_nest_cancel(msg->skb, prop);
2619attr_msg_full:
2620 nla_nest_cancel(msg->skb, attrs);
2621msg_full:
2622 tipc_bcast_unlock(net);
2623 genlmsg_cancel(msg->skb, hdr);
2624
2625 return -EMSGSIZE;
2626}
2627
2628void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2629 struct sk_buff_head *xmitq)
2630{
2631 l->tolerance = tol;
2632 if (l->bc_rcvlink)
2633 l->bc_rcvlink->tolerance = tol;
2634 if (link_is_up(l))
2635 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2636}
2637
2638void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2639 struct sk_buff_head *xmitq)
2640{
2641 l->priority = prio;
2642 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2643}
2644
2645void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2646{
2647 l->abort_limit = limit;
2648}
2649
2650char *tipc_link_name_ext(struct tipc_link *l, char *buf)
2651{
2652 if (!l)
2653 scnprintf(buf, TIPC_MAX_LINK_NAME, "null");
2654 else if (link_is_bc_sndlink(l))
2655 scnprintf(buf, TIPC_MAX_LINK_NAME, "broadcast-sender");
2656 else if (link_is_bc_rcvlink(l))
2657 scnprintf(buf, TIPC_MAX_LINK_NAME,
2658 "broadcast-receiver, peer %x", l->addr);
2659 else
2660 memcpy(buf, l->name, TIPC_MAX_LINK_NAME);
2661
2662 return buf;
2663}
2664
2665/**
2666 * tipc_link_dump - dump TIPC link data
2667 * @l: tipc link to be dumped
2668 * @dqueues: bitmask to decide if any link queue to be dumped?
2669 * - TIPC_DUMP_NONE: don't dump link queues
2670 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2671 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2672 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2673 * - TIPC_DUMP_INPUTQ: dump link input queue
2674 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2675 * - TIPC_DUMP_ALL: dump all the link queues above
2676 * @buf: returned buffer of dump data in format
2677 */
2678int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2679{
2680 int i = 0;
2681 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2682 struct sk_buff_head *list;
2683 struct sk_buff *hskb, *tskb;
2684 u32 len;
2685
2686 if (!l) {
2687 i += scnprintf(buf, sz, "link data: (null)\n");
2688 return i;
2689 }
2690
2691 i += scnprintf(buf, sz, "link data: %x", l->addr);
2692 i += scnprintf(buf + i, sz - i, " %x", l->state);
2693 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2694 i += scnprintf(buf + i, sz - i, " %u", l->session);
2695 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2696 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2697 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2698 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2699 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2700 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2701 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2702 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2703 i += scnprintf(buf + i, sz - i, " %u", 0);
2704 i += scnprintf(buf + i, sz - i, " %u", 0);
2705 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2706
2707 list = &l->transmq;
2708 len = skb_queue_len(list);
2709 hskb = skb_peek(list);
2710 tskb = skb_peek_tail(list);
2711 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2712 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2713 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2714
2715 list = &l->deferdq;
2716 len = skb_queue_len(list);
2717 hskb = skb_peek(list);
2718 tskb = skb_peek_tail(list);
2719 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2720 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2721 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2722
2723 list = &l->backlogq;
2724 len = skb_queue_len(list);
2725 hskb = skb_peek(list);
2726 tskb = skb_peek_tail(list);
2727 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2728 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2729 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2730
2731 list = l->inputq;
2732 len = skb_queue_len(list);
2733 hskb = skb_peek(list);
2734 tskb = skb_peek_tail(list);
2735 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2736 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2737 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2738
2739 if (dqueues & TIPC_DUMP_TRANSMQ) {
2740 i += scnprintf(buf + i, sz - i, "transmq: ");
2741 i += tipc_list_dump(&l->transmq, false, buf + i);
2742 }
2743 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2744 i += scnprintf(buf + i, sz - i,
2745 "backlogq: <%u %u %u %u %u>, ",
2746 l->backlog[TIPC_LOW_IMPORTANCE].len,
2747 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2748 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2749 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2750 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2751 i += tipc_list_dump(&l->backlogq, false, buf + i);
2752 }
2753 if (dqueues & TIPC_DUMP_DEFERDQ) {
2754 i += scnprintf(buf + i, sz - i, "deferdq: ");
2755 i += tipc_list_dump(&l->deferdq, false, buf + i);
2756 }
2757 if (dqueues & TIPC_DUMP_INPUTQ) {
2758 i += scnprintf(buf + i, sz - i, "inputq: ");
2759 i += tipc_list_dump(l->inputq, false, buf + i);
2760 }
2761 if (dqueues & TIPC_DUMP_WAKEUP) {
2762 i += scnprintf(buf + i, sz - i, "wakeup: ");
2763 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2764 }
2765
2766 return i;
2767}