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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
47#include <linux/pkt_sched.h>
48
49struct tipc_stats {
50 u32 sent_pkts;
51 u32 recv_pkts;
52 u32 sent_states;
53 u32 recv_states;
54 u32 sent_probes;
55 u32 recv_probes;
56 u32 sent_nacks;
57 u32 recv_nacks;
58 u32 sent_acks;
59 u32 sent_bundled;
60 u32 sent_bundles;
61 u32 recv_bundled;
62 u32 recv_bundles;
63 u32 retransmitted;
64 u32 sent_fragmented;
65 u32 sent_fragments;
66 u32 recv_fragmented;
67 u32 recv_fragments;
68 u32 link_congs; /* # port sends blocked by congestion */
69 u32 deferred_recv;
70 u32 duplicates;
71 u32 max_queue_sz; /* send queue size high water mark */
72 u32 accu_queue_sz; /* used for send queue size profiling */
73 u32 queue_sz_counts; /* used for send queue size profiling */
74 u32 msg_length_counts; /* used for message length profiling */
75 u32 msg_lengths_total; /* used for message length profiling */
76 u32 msg_length_profile[7]; /* used for msg. length profiling */
77};
78
79/**
80 * struct tipc_link - TIPC link data structure
81 * @addr: network address of link's peer node
82 * @name: link name character string
83 * @media_addr: media address to use when sending messages over link
84 * @timer: link timer
85 * @net: pointer to namespace struct
86 * @refcnt: reference counter for permanent references (owner node & timer)
87 * @peer_session: link session # being used by peer end of link
88 * @peer_bearer_id: bearer id used by link's peer endpoint
89 * @bearer_id: local bearer id used by link
90 * @tolerance: minimum link continuity loss needed to reset link [in ms]
91 * @abort_limit: # of unacknowledged continuity probes needed to reset link
92 * @state: current state of link FSM
93 * @peer_caps: bitmap describing capabilities of peer node
94 * @silent_intv_cnt: # of timer intervals without any reception from peer
95 * @proto_msg: template for control messages generated by link
96 * @pmsg: convenience pointer to "proto_msg" field
97 * @priority: current link priority
98 * @net_plane: current link network plane ('A' through 'H')
99 * @mon_state: cookie with information needed by link monitor
100 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
101 * @exp_msg_count: # of tunnelled messages expected during link changeover
102 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
103 * @mtu: current maximum packet size for this link
104 * @advertised_mtu: advertised own mtu when link is being established
105 * @transmitq: queue for sent, non-acked messages
106 * @backlogq: queue for messages waiting to be sent
107 * @snt_nxt: next sequence number to use for outbound messages
108 * @last_retransmitted: sequence number of most recently retransmitted message
109 * @stale_count: # of identical retransmit requests made by peer
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 */
124struct tipc_link {
125 u32 addr;
126 char name[TIPC_MAX_LINK_NAME];
127 struct net *net;
128
129 /* Management and link supervision data */
130 u32 peer_session;
131 u32 session;
132 u32 peer_bearer_id;
133 u32 bearer_id;
134 u32 tolerance;
135 u32 abort_limit;
136 u32 state;
137 u16 peer_caps;
138 bool active;
139 u32 silent_intv_cnt;
140 char if_name[TIPC_MAX_IF_NAME];
141 u32 priority;
142 char net_plane;
143 struct tipc_mon_state mon_state;
144 u16 rst_cnt;
145
146 /* Failover/synch */
147 u16 drop_point;
148 struct sk_buff *failover_reasm_skb;
149
150 /* Max packet negotiation */
151 u16 mtu;
152 u16 advertised_mtu;
153
154 /* Sending */
155 struct sk_buff_head transmq;
156 struct sk_buff_head backlogq;
157 struct {
158 u16 len;
159 u16 limit;
160 } backlog[5];
161 u16 snd_nxt;
162 u16 last_retransm;
163 u16 window;
164 u32 stale_count;
165
166 /* Reception */
167 u16 rcv_nxt;
168 u32 rcv_unacked;
169 struct sk_buff_head deferdq;
170 struct sk_buff_head *inputq;
171 struct sk_buff_head *namedq;
172
173 /* Congestion handling */
174 struct sk_buff_head wakeupq;
175
176 /* Fragmentation/reassembly */
177 struct sk_buff *reasm_buf;
178
179 /* Broadcast */
180 u16 ackers;
181 u16 acked;
182 struct tipc_link *bc_rcvlink;
183 struct tipc_link *bc_sndlink;
184 unsigned long prev_retr;
185 u16 prev_from;
186 u16 prev_to;
187 u8 nack_state;
188 bool bc_peer_is_up;
189
190 /* Statistics */
191 struct tipc_stats stats;
192};
193
194/*
195 * Error message prefixes
196 */
197static const char *link_co_err = "Link tunneling error, ";
198static const char *link_rst_msg = "Resetting link ";
199
200/* Send states for broadcast NACKs
201 */
202enum {
203 BC_NACK_SND_CONDITIONAL,
204 BC_NACK_SND_UNCONDITIONAL,
205 BC_NACK_SND_SUPPRESS,
206};
207
208#define TIPC_BC_RETR_LIMIT 10 /* [ms] */
209
210/*
211 * Interval between NACKs when packets arrive out of order
212 */
213#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
214
215/* Wildcard value for link session numbers. When it is known that
216 * peer endpoint is down, any session number must be accepted.
217 */
218#define ANY_SESSION 0x10000
219
220/* Link FSM states:
221 */
222enum {
223 LINK_ESTABLISHED = 0xe,
224 LINK_ESTABLISHING = 0xe << 4,
225 LINK_RESET = 0x1 << 8,
226 LINK_RESETTING = 0x2 << 12,
227 LINK_PEER_RESET = 0xd << 16,
228 LINK_FAILINGOVER = 0xf << 20,
229 LINK_SYNCHING = 0xc << 24
230};
231
232/* Link FSM state checking routines
233 */
234static int link_is_up(struct tipc_link *l)
235{
236 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
237}
238
239static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
240 struct sk_buff_head *xmitq);
241static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
242 u16 rcvgap, int tolerance, int priority,
243 struct sk_buff_head *xmitq);
244static void link_print(struct tipc_link *l, const char *str);
245static int tipc_link_build_nack_msg(struct tipc_link *l,
246 struct sk_buff_head *xmitq);
247static void tipc_link_build_bc_init_msg(struct tipc_link *l,
248 struct sk_buff_head *xmitq);
249static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
250
251/*
252 * Simple non-static link routines (i.e. referenced outside this file)
253 */
254bool tipc_link_is_up(struct tipc_link *l)
255{
256 return link_is_up(l);
257}
258
259bool tipc_link_peer_is_down(struct tipc_link *l)
260{
261 return l->state == LINK_PEER_RESET;
262}
263
264bool tipc_link_is_reset(struct tipc_link *l)
265{
266 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
267}
268
269bool tipc_link_is_establishing(struct tipc_link *l)
270{
271 return l->state == LINK_ESTABLISHING;
272}
273
274bool tipc_link_is_synching(struct tipc_link *l)
275{
276 return l->state == LINK_SYNCHING;
277}
278
279bool tipc_link_is_failingover(struct tipc_link *l)
280{
281 return l->state == LINK_FAILINGOVER;
282}
283
284bool tipc_link_is_blocked(struct tipc_link *l)
285{
286 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
287}
288
289static bool link_is_bc_sndlink(struct tipc_link *l)
290{
291 return !l->bc_sndlink;
292}
293
294static bool link_is_bc_rcvlink(struct tipc_link *l)
295{
296 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
297}
298
299int tipc_link_is_active(struct tipc_link *l)
300{
301 return l->active;
302}
303
304void tipc_link_set_active(struct tipc_link *l, bool active)
305{
306 l->active = active;
307}
308
309u32 tipc_link_id(struct tipc_link *l)
310{
311 return l->peer_bearer_id << 16 | l->bearer_id;
312}
313
314int tipc_link_window(struct tipc_link *l)
315{
316 return l->window;
317}
318
319int tipc_link_prio(struct tipc_link *l)
320{
321 return l->priority;
322}
323
324unsigned long tipc_link_tolerance(struct tipc_link *l)
325{
326 return l->tolerance;
327}
328
329struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
330{
331 return l->inputq;
332}
333
334char tipc_link_plane(struct tipc_link *l)
335{
336 return l->net_plane;
337}
338
339void tipc_link_add_bc_peer(struct tipc_link *snd_l,
340 struct tipc_link *uc_l,
341 struct sk_buff_head *xmitq)
342{
343 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
344
345 snd_l->ackers++;
346 rcv_l->acked = snd_l->snd_nxt - 1;
347 snd_l->state = LINK_ESTABLISHED;
348 tipc_link_build_bc_init_msg(uc_l, xmitq);
349}
350
351void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
352 struct tipc_link *rcv_l,
353 struct sk_buff_head *xmitq)
354{
355 u16 ack = snd_l->snd_nxt - 1;
356
357 snd_l->ackers--;
358 rcv_l->bc_peer_is_up = true;
359 rcv_l->state = LINK_ESTABLISHED;
360 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
361 tipc_link_reset(rcv_l);
362 rcv_l->state = LINK_RESET;
363 if (!snd_l->ackers) {
364 tipc_link_reset(snd_l);
365 snd_l->state = LINK_RESET;
366 __skb_queue_purge(xmitq);
367 }
368}
369
370int tipc_link_bc_peers(struct tipc_link *l)
371{
372 return l->ackers;
373}
374
375u16 link_bc_rcv_gap(struct tipc_link *l)
376{
377 struct sk_buff *skb = skb_peek(&l->deferdq);
378 u16 gap = 0;
379
380 if (more(l->snd_nxt, l->rcv_nxt))
381 gap = l->snd_nxt - l->rcv_nxt;
382 if (skb)
383 gap = buf_seqno(skb) - l->rcv_nxt;
384 return gap;
385}
386
387void tipc_link_set_mtu(struct tipc_link *l, int mtu)
388{
389 l->mtu = mtu;
390}
391
392int tipc_link_mtu(struct tipc_link *l)
393{
394 return l->mtu;
395}
396
397u16 tipc_link_rcv_nxt(struct tipc_link *l)
398{
399 return l->rcv_nxt;
400}
401
402u16 tipc_link_acked(struct tipc_link *l)
403{
404 return l->acked;
405}
406
407char *tipc_link_name(struct tipc_link *l)
408{
409 return l->name;
410}
411
412/**
413 * tipc_link_create - create a new link
414 * @n: pointer to associated node
415 * @if_name: associated interface name
416 * @bearer_id: id (index) of associated bearer
417 * @tolerance: link tolerance to be used by link
418 * @net_plane: network plane (A,B,c..) this link belongs to
419 * @mtu: mtu to be advertised by link
420 * @priority: priority to be used by link
421 * @window: send window to be used by link
422 * @session: session to be used by link
423 * @ownnode: identity of own node
424 * @peer: node id of peer node
425 * @peer_caps: bitmap describing peer node capabilities
426 * @bc_sndlink: the namespace global link used for broadcast sending
427 * @bc_rcvlink: the peer specific link used for broadcast reception
428 * @inputq: queue to put messages ready for delivery
429 * @namedq: queue to put binding table update messages ready for delivery
430 * @link: return value, pointer to put the created link
431 *
432 * Returns true if link was created, otherwise false
433 */
434bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
435 int tolerance, char net_plane, u32 mtu, int priority,
436 int window, u32 session, u32 ownnode, u32 peer,
437 u16 peer_caps,
438 struct tipc_link *bc_sndlink,
439 struct tipc_link *bc_rcvlink,
440 struct sk_buff_head *inputq,
441 struct sk_buff_head *namedq,
442 struct tipc_link **link)
443{
444 struct tipc_link *l;
445
446 l = kzalloc(sizeof(*l), GFP_ATOMIC);
447 if (!l)
448 return false;
449 *link = l;
450 l->session = session;
451
452 /* Note: peer i/f name is completed by reset/activate message */
453 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
454 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
455 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
456 strcpy(l->if_name, if_name);
457 l->addr = peer;
458 l->peer_caps = peer_caps;
459 l->net = net;
460 l->peer_session = ANY_SESSION;
461 l->bearer_id = bearer_id;
462 l->tolerance = tolerance;
463 l->net_plane = net_plane;
464 l->advertised_mtu = mtu;
465 l->mtu = mtu;
466 l->priority = priority;
467 tipc_link_set_queue_limits(l, window);
468 l->ackers = 1;
469 l->bc_sndlink = bc_sndlink;
470 l->bc_rcvlink = bc_rcvlink;
471 l->inputq = inputq;
472 l->namedq = namedq;
473 l->state = LINK_RESETTING;
474 __skb_queue_head_init(&l->transmq);
475 __skb_queue_head_init(&l->backlogq);
476 __skb_queue_head_init(&l->deferdq);
477 skb_queue_head_init(&l->wakeupq);
478 skb_queue_head_init(l->inputq);
479 return true;
480}
481
482/**
483 * tipc_link_bc_create - create new link to be used for broadcast
484 * @n: pointer to associated node
485 * @mtu: mtu to be used
486 * @window: send window to be used
487 * @inputq: queue to put messages ready for delivery
488 * @namedq: queue to put binding table update messages ready for delivery
489 * @link: return value, pointer to put the created link
490 *
491 * Returns true if link was created, otherwise false
492 */
493bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
494 int mtu, int window, u16 peer_caps,
495 struct sk_buff_head *inputq,
496 struct sk_buff_head *namedq,
497 struct tipc_link *bc_sndlink,
498 struct tipc_link **link)
499{
500 struct tipc_link *l;
501
502 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
503 0, ownnode, peer, peer_caps, bc_sndlink,
504 NULL, inputq, namedq, link))
505 return false;
506
507 l = *link;
508 strcpy(l->name, tipc_bclink_name);
509 tipc_link_reset(l);
510 l->state = LINK_RESET;
511 l->ackers = 0;
512 l->bc_rcvlink = l;
513
514 /* Broadcast send link is always up */
515 if (link_is_bc_sndlink(l))
516 l->state = LINK_ESTABLISHED;
517
518 return true;
519}
520
521/**
522 * tipc_link_fsm_evt - link finite state machine
523 * @l: pointer to link
524 * @evt: state machine event to be processed
525 */
526int tipc_link_fsm_evt(struct tipc_link *l, int evt)
527{
528 int rc = 0;
529
530 switch (l->state) {
531 case LINK_RESETTING:
532 switch (evt) {
533 case LINK_PEER_RESET_EVT:
534 l->state = LINK_PEER_RESET;
535 break;
536 case LINK_RESET_EVT:
537 l->state = LINK_RESET;
538 break;
539 case LINK_FAILURE_EVT:
540 case LINK_FAILOVER_BEGIN_EVT:
541 case LINK_ESTABLISH_EVT:
542 case LINK_FAILOVER_END_EVT:
543 case LINK_SYNCH_BEGIN_EVT:
544 case LINK_SYNCH_END_EVT:
545 default:
546 goto illegal_evt;
547 }
548 break;
549 case LINK_RESET:
550 switch (evt) {
551 case LINK_PEER_RESET_EVT:
552 l->state = LINK_ESTABLISHING;
553 break;
554 case LINK_FAILOVER_BEGIN_EVT:
555 l->state = LINK_FAILINGOVER;
556 case LINK_FAILURE_EVT:
557 case LINK_RESET_EVT:
558 case LINK_ESTABLISH_EVT:
559 case LINK_FAILOVER_END_EVT:
560 break;
561 case LINK_SYNCH_BEGIN_EVT:
562 case LINK_SYNCH_END_EVT:
563 default:
564 goto illegal_evt;
565 }
566 break;
567 case LINK_PEER_RESET:
568 switch (evt) {
569 case LINK_RESET_EVT:
570 l->state = LINK_ESTABLISHING;
571 break;
572 case LINK_PEER_RESET_EVT:
573 case LINK_ESTABLISH_EVT:
574 case LINK_FAILURE_EVT:
575 break;
576 case LINK_SYNCH_BEGIN_EVT:
577 case LINK_SYNCH_END_EVT:
578 case LINK_FAILOVER_BEGIN_EVT:
579 case LINK_FAILOVER_END_EVT:
580 default:
581 goto illegal_evt;
582 }
583 break;
584 case LINK_FAILINGOVER:
585 switch (evt) {
586 case LINK_FAILOVER_END_EVT:
587 l->state = LINK_RESET;
588 break;
589 case LINK_PEER_RESET_EVT:
590 case LINK_RESET_EVT:
591 case LINK_ESTABLISH_EVT:
592 case LINK_FAILURE_EVT:
593 break;
594 case LINK_FAILOVER_BEGIN_EVT:
595 case LINK_SYNCH_BEGIN_EVT:
596 case LINK_SYNCH_END_EVT:
597 default:
598 goto illegal_evt;
599 }
600 break;
601 case LINK_ESTABLISHING:
602 switch (evt) {
603 case LINK_ESTABLISH_EVT:
604 l->state = LINK_ESTABLISHED;
605 break;
606 case LINK_FAILOVER_BEGIN_EVT:
607 l->state = LINK_FAILINGOVER;
608 break;
609 case LINK_RESET_EVT:
610 l->state = LINK_RESET;
611 break;
612 case LINK_FAILURE_EVT:
613 case LINK_PEER_RESET_EVT:
614 case LINK_SYNCH_BEGIN_EVT:
615 case LINK_FAILOVER_END_EVT:
616 break;
617 case LINK_SYNCH_END_EVT:
618 default:
619 goto illegal_evt;
620 }
621 break;
622 case LINK_ESTABLISHED:
623 switch (evt) {
624 case LINK_PEER_RESET_EVT:
625 l->state = LINK_PEER_RESET;
626 rc |= TIPC_LINK_DOWN_EVT;
627 break;
628 case LINK_FAILURE_EVT:
629 l->state = LINK_RESETTING;
630 rc |= TIPC_LINK_DOWN_EVT;
631 break;
632 case LINK_RESET_EVT:
633 l->state = LINK_RESET;
634 break;
635 case LINK_ESTABLISH_EVT:
636 case LINK_SYNCH_END_EVT:
637 break;
638 case LINK_SYNCH_BEGIN_EVT:
639 l->state = LINK_SYNCHING;
640 break;
641 case LINK_FAILOVER_BEGIN_EVT:
642 case LINK_FAILOVER_END_EVT:
643 default:
644 goto illegal_evt;
645 }
646 break;
647 case LINK_SYNCHING:
648 switch (evt) {
649 case LINK_PEER_RESET_EVT:
650 l->state = LINK_PEER_RESET;
651 rc |= TIPC_LINK_DOWN_EVT;
652 break;
653 case LINK_FAILURE_EVT:
654 l->state = LINK_RESETTING;
655 rc |= TIPC_LINK_DOWN_EVT;
656 break;
657 case LINK_RESET_EVT:
658 l->state = LINK_RESET;
659 break;
660 case LINK_ESTABLISH_EVT:
661 case LINK_SYNCH_BEGIN_EVT:
662 break;
663 case LINK_SYNCH_END_EVT:
664 l->state = LINK_ESTABLISHED;
665 break;
666 case LINK_FAILOVER_BEGIN_EVT:
667 case LINK_FAILOVER_END_EVT:
668 default:
669 goto illegal_evt;
670 }
671 break;
672 default:
673 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
674 }
675 return rc;
676illegal_evt:
677 pr_err("Illegal FSM event %x in state %x on link %s\n",
678 evt, l->state, l->name);
679 return rc;
680}
681
682/* link_profile_stats - update statistical profiling of traffic
683 */
684static void link_profile_stats(struct tipc_link *l)
685{
686 struct sk_buff *skb;
687 struct tipc_msg *msg;
688 int length;
689
690 /* Update counters used in statistical profiling of send traffic */
691 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
692 l->stats.queue_sz_counts++;
693
694 skb = skb_peek(&l->transmq);
695 if (!skb)
696 return;
697 msg = buf_msg(skb);
698 length = msg_size(msg);
699
700 if (msg_user(msg) == MSG_FRAGMENTER) {
701 if (msg_type(msg) != FIRST_FRAGMENT)
702 return;
703 length = msg_size(msg_get_wrapped(msg));
704 }
705 l->stats.msg_lengths_total += length;
706 l->stats.msg_length_counts++;
707 if (length <= 64)
708 l->stats.msg_length_profile[0]++;
709 else if (length <= 256)
710 l->stats.msg_length_profile[1]++;
711 else if (length <= 1024)
712 l->stats.msg_length_profile[2]++;
713 else if (length <= 4096)
714 l->stats.msg_length_profile[3]++;
715 else if (length <= 16384)
716 l->stats.msg_length_profile[4]++;
717 else if (length <= 32768)
718 l->stats.msg_length_profile[5]++;
719 else
720 l->stats.msg_length_profile[6]++;
721}
722
723/* tipc_link_timeout - perform periodic task as instructed from node timeout
724 */
725int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
726{
727 int mtyp = 0;
728 int rc = 0;
729 bool state = false;
730 bool probe = false;
731 bool setup = false;
732 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
733 u16 bc_acked = l->bc_rcvlink->acked;
734 struct tipc_mon_state *mstate = &l->mon_state;
735
736 switch (l->state) {
737 case LINK_ESTABLISHED:
738 case LINK_SYNCHING:
739 mtyp = STATE_MSG;
740 link_profile_stats(l);
741 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
742 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
743 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
744 state = bc_acked != bc_snt;
745 state |= l->bc_rcvlink->rcv_unacked;
746 state |= l->rcv_unacked;
747 state |= !skb_queue_empty(&l->transmq);
748 state |= !skb_queue_empty(&l->deferdq);
749 probe = mstate->probing;
750 probe |= l->silent_intv_cnt;
751 if (probe || mstate->monitoring)
752 l->silent_intv_cnt++;
753 break;
754 case LINK_RESET:
755 setup = l->rst_cnt++ <= 4;
756 setup |= !(l->rst_cnt % 16);
757 mtyp = RESET_MSG;
758 break;
759 case LINK_ESTABLISHING:
760 setup = true;
761 mtyp = ACTIVATE_MSG;
762 break;
763 case LINK_PEER_RESET:
764 case LINK_RESETTING:
765 case LINK_FAILINGOVER:
766 break;
767 default:
768 break;
769 }
770
771 if (state || probe || setup)
772 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, xmitq);
773
774 return rc;
775}
776
777/**
778 * link_schedule_user - schedule a message sender for wakeup after congestion
779 * @link: congested link
780 * @list: message that was attempted sent
781 * Create pseudo msg to send back to user when congestion abates
782 * Does not consume buffer list
783 */
784static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
785{
786 struct tipc_msg *msg = buf_msg(skb_peek(list));
787 int imp = msg_importance(msg);
788 u32 oport = msg_origport(msg);
789 u32 addr = tipc_own_addr(link->net);
790 struct sk_buff *skb;
791
792 /* This really cannot happen... */
793 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
794 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
795 return -ENOBUFS;
796 }
797 /* Non-blocking sender: */
798 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
799 return -ELINKCONG;
800
801 /* Create and schedule wakeup pseudo message */
802 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
803 addr, addr, oport, 0, 0);
804 if (!skb)
805 return -ENOBUFS;
806 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
807 TIPC_SKB_CB(skb)->chain_imp = imp;
808 skb_queue_tail(&link->wakeupq, skb);
809 link->stats.link_congs++;
810 return -ELINKCONG;
811}
812
813/**
814 * link_prepare_wakeup - prepare users for wakeup after congestion
815 * @link: congested link
816 * Move a number of waiting users, as permitted by available space in
817 * the send queue, from link wait queue to node wait queue for wakeup
818 */
819void link_prepare_wakeup(struct tipc_link *l)
820{
821 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
822 int imp, lim;
823 struct sk_buff *skb, *tmp;
824
825 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
826 imp = TIPC_SKB_CB(skb)->chain_imp;
827 lim = l->backlog[imp].limit;
828 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
829 if ((pnd[imp] + l->backlog[imp].len) >= lim)
830 break;
831 skb_unlink(skb, &l->wakeupq);
832 skb_queue_tail(l->inputq, skb);
833 }
834}
835
836void tipc_link_reset(struct tipc_link *l)
837{
838 l->peer_session = ANY_SESSION;
839 l->session++;
840 l->mtu = l->advertised_mtu;
841 __skb_queue_purge(&l->transmq);
842 __skb_queue_purge(&l->deferdq);
843 skb_queue_splice_init(&l->wakeupq, l->inputq);
844 __skb_queue_purge(&l->backlogq);
845 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
846 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
847 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
848 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
849 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
850 kfree_skb(l->reasm_buf);
851 kfree_skb(l->failover_reasm_skb);
852 l->reasm_buf = NULL;
853 l->failover_reasm_skb = NULL;
854 l->rcv_unacked = 0;
855 l->snd_nxt = 1;
856 l->rcv_nxt = 1;
857 l->acked = 0;
858 l->silent_intv_cnt = 0;
859 l->rst_cnt = 0;
860 l->stale_count = 0;
861 l->bc_peer_is_up = false;
862 memset(&l->mon_state, 0, sizeof(l->mon_state));
863 tipc_link_reset_stats(l);
864}
865
866/**
867 * tipc_link_xmit(): enqueue buffer list according to queue situation
868 * @link: link to use
869 * @list: chain of buffers containing message
870 * @xmitq: returned list of packets to be sent by caller
871 *
872 * Consumes the buffer chain, except when returning -ELINKCONG,
873 * since the caller then may want to make more send attempts.
874 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
875 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
876 */
877int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
878 struct sk_buff_head *xmitq)
879{
880 struct tipc_msg *hdr = buf_msg(skb_peek(list));
881 unsigned int maxwin = l->window;
882 unsigned int i, imp = msg_importance(hdr);
883 unsigned int mtu = l->mtu;
884 u16 ack = l->rcv_nxt - 1;
885 u16 seqno = l->snd_nxt;
886 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
887 struct sk_buff_head *transmq = &l->transmq;
888 struct sk_buff_head *backlogq = &l->backlogq;
889 struct sk_buff *skb, *_skb, *bskb;
890 int pkt_cnt = skb_queue_len(list);
891
892 /* Match msg importance against this and all higher backlog limits: */
893 if (!skb_queue_empty(backlogq)) {
894 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
895 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
896 return link_schedule_user(l, list);
897 }
898 }
899 if (unlikely(msg_size(hdr) > mtu)) {
900 skb_queue_purge(list);
901 return -EMSGSIZE;
902 }
903
904 if (pkt_cnt > 1) {
905 l->stats.sent_fragmented++;
906 l->stats.sent_fragments += pkt_cnt;
907 }
908
909 /* Prepare each packet for sending, and add to relevant queue: */
910 while (skb_queue_len(list)) {
911 skb = skb_peek(list);
912 hdr = buf_msg(skb);
913 msg_set_seqno(hdr, seqno);
914 msg_set_ack(hdr, ack);
915 msg_set_bcast_ack(hdr, bc_ack);
916
917 if (likely(skb_queue_len(transmq) < maxwin)) {
918 _skb = skb_clone(skb, GFP_ATOMIC);
919 if (!_skb) {
920 skb_queue_purge(list);
921 return -ENOBUFS;
922 }
923 __skb_dequeue(list);
924 __skb_queue_tail(transmq, skb);
925 __skb_queue_tail(xmitq, _skb);
926 TIPC_SKB_CB(skb)->ackers = l->ackers;
927 l->rcv_unacked = 0;
928 l->stats.sent_pkts++;
929 seqno++;
930 continue;
931 }
932 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
933 kfree_skb(__skb_dequeue(list));
934 l->stats.sent_bundled++;
935 continue;
936 }
937 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
938 kfree_skb(__skb_dequeue(list));
939 __skb_queue_tail(backlogq, bskb);
940 l->backlog[msg_importance(buf_msg(bskb))].len++;
941 l->stats.sent_bundled++;
942 l->stats.sent_bundles++;
943 continue;
944 }
945 l->backlog[imp].len += skb_queue_len(list);
946 skb_queue_splice_tail_init(list, backlogq);
947 }
948 l->snd_nxt = seqno;
949 return 0;
950}
951
952void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
953{
954 struct sk_buff *skb, *_skb;
955 struct tipc_msg *hdr;
956 u16 seqno = l->snd_nxt;
957 u16 ack = l->rcv_nxt - 1;
958 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
959
960 while (skb_queue_len(&l->transmq) < l->window) {
961 skb = skb_peek(&l->backlogq);
962 if (!skb)
963 break;
964 _skb = skb_clone(skb, GFP_ATOMIC);
965 if (!_skb)
966 break;
967 __skb_dequeue(&l->backlogq);
968 hdr = buf_msg(skb);
969 l->backlog[msg_importance(hdr)].len--;
970 __skb_queue_tail(&l->transmq, skb);
971 __skb_queue_tail(xmitq, _skb);
972 TIPC_SKB_CB(skb)->ackers = l->ackers;
973 msg_set_seqno(hdr, seqno);
974 msg_set_ack(hdr, ack);
975 msg_set_bcast_ack(hdr, bc_ack);
976 l->rcv_unacked = 0;
977 l->stats.sent_pkts++;
978 seqno++;
979 }
980 l->snd_nxt = seqno;
981}
982
983static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
984{
985 struct tipc_msg *hdr = buf_msg(skb);
986
987 pr_warn("Retransmission failure on link <%s>\n", l->name);
988 link_print(l, "Resetting link ");
989 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
990 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
991 pr_info("sqno %u, prev: %x, src: %x\n",
992 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
993}
994
995int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
996 struct sk_buff_head *xmitq)
997{
998 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
999 struct tipc_msg *hdr;
1000 u16 ack = l->rcv_nxt - 1;
1001 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1002
1003 if (!skb)
1004 return 0;
1005
1006 /* Detect repeated retransmit failures on same packet */
1007 if (likely(l->last_retransm != buf_seqno(skb))) {
1008 l->last_retransm = buf_seqno(skb);
1009 l->stale_count = 1;
1010 } else if (++l->stale_count > 100) {
1011 link_retransmit_failure(l, skb);
1012 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1013 }
1014
1015 /* Move forward to where retransmission should start */
1016 skb_queue_walk(&l->transmq, skb) {
1017 if (!less(buf_seqno(skb), from))
1018 break;
1019 }
1020
1021 skb_queue_walk_from(&l->transmq, skb) {
1022 if (more(buf_seqno(skb), to))
1023 break;
1024 hdr = buf_msg(skb);
1025 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
1026 if (!_skb)
1027 return 0;
1028 hdr = buf_msg(_skb);
1029 msg_set_ack(hdr, ack);
1030 msg_set_bcast_ack(hdr, bc_ack);
1031 _skb->priority = TC_PRIO_CONTROL;
1032 __skb_queue_tail(xmitq, _skb);
1033 l->stats.retransmitted++;
1034 }
1035 return 0;
1036}
1037
1038/* tipc_data_input - deliver data and name distr msgs to upper layer
1039 *
1040 * Consumes buffer if message is of right type
1041 * Node lock must be held
1042 */
1043static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1044 struct sk_buff_head *inputq)
1045{
1046 switch (msg_user(buf_msg(skb))) {
1047 case TIPC_LOW_IMPORTANCE:
1048 case TIPC_MEDIUM_IMPORTANCE:
1049 case TIPC_HIGH_IMPORTANCE:
1050 case TIPC_CRITICAL_IMPORTANCE:
1051 case CONN_MANAGER:
1052 skb_queue_tail(inputq, skb);
1053 return true;
1054 case NAME_DISTRIBUTOR:
1055 l->bc_rcvlink->state = LINK_ESTABLISHED;
1056 skb_queue_tail(l->namedq, skb);
1057 return true;
1058 case MSG_BUNDLER:
1059 case TUNNEL_PROTOCOL:
1060 case MSG_FRAGMENTER:
1061 case BCAST_PROTOCOL:
1062 return false;
1063 default:
1064 pr_warn("Dropping received illegal msg type\n");
1065 kfree_skb(skb);
1066 return false;
1067 };
1068}
1069
1070/* tipc_link_input - process packet that has passed link protocol check
1071 *
1072 * Consumes buffer
1073 */
1074static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1075 struct sk_buff_head *inputq)
1076{
1077 struct tipc_msg *hdr = buf_msg(skb);
1078 struct sk_buff **reasm_skb = &l->reasm_buf;
1079 struct sk_buff *iskb;
1080 struct sk_buff_head tmpq;
1081 int usr = msg_user(hdr);
1082 int rc = 0;
1083 int pos = 0;
1084 int ipos = 0;
1085
1086 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1087 if (msg_type(hdr) == SYNCH_MSG) {
1088 __skb_queue_purge(&l->deferdq);
1089 goto drop;
1090 }
1091 if (!tipc_msg_extract(skb, &iskb, &ipos))
1092 return rc;
1093 kfree_skb(skb);
1094 skb = iskb;
1095 hdr = buf_msg(skb);
1096 if (less(msg_seqno(hdr), l->drop_point))
1097 goto drop;
1098 if (tipc_data_input(l, skb, inputq))
1099 return rc;
1100 usr = msg_user(hdr);
1101 reasm_skb = &l->failover_reasm_skb;
1102 }
1103
1104 if (usr == MSG_BUNDLER) {
1105 skb_queue_head_init(&tmpq);
1106 l->stats.recv_bundles++;
1107 l->stats.recv_bundled += msg_msgcnt(hdr);
1108 while (tipc_msg_extract(skb, &iskb, &pos))
1109 tipc_data_input(l, iskb, &tmpq);
1110 tipc_skb_queue_splice_tail(&tmpq, inputq);
1111 return 0;
1112 } else if (usr == MSG_FRAGMENTER) {
1113 l->stats.recv_fragments++;
1114 if (tipc_buf_append(reasm_skb, &skb)) {
1115 l->stats.recv_fragmented++;
1116 tipc_data_input(l, skb, inputq);
1117 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1118 pr_warn_ratelimited("Unable to build fragment list\n");
1119 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1120 }
1121 return 0;
1122 } else if (usr == BCAST_PROTOCOL) {
1123 tipc_bcast_lock(l->net);
1124 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1125 tipc_bcast_unlock(l->net);
1126 }
1127drop:
1128 kfree_skb(skb);
1129 return 0;
1130}
1131
1132static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1133{
1134 bool released = false;
1135 struct sk_buff *skb, *tmp;
1136
1137 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1138 if (more(buf_seqno(skb), acked))
1139 break;
1140 __skb_unlink(skb, &l->transmq);
1141 kfree_skb(skb);
1142 released = true;
1143 }
1144 return released;
1145}
1146
1147/* tipc_link_build_state_msg: prepare link state message for transmission
1148 *
1149 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1150 * risk of ack storms towards the sender
1151 */
1152int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1153{
1154 if (!l)
1155 return 0;
1156
1157 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1158 if (link_is_bc_rcvlink(l)) {
1159 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1160 return 0;
1161 l->rcv_unacked = 0;
1162
1163 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1164 l->snd_nxt = l->rcv_nxt;
1165 return TIPC_LINK_SND_STATE;
1166 }
1167
1168 /* Unicast ACK */
1169 l->rcv_unacked = 0;
1170 l->stats.sent_acks++;
1171 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1172 return 0;
1173}
1174
1175/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1176 */
1177void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1178{
1179 int mtyp = RESET_MSG;
1180 struct sk_buff *skb;
1181
1182 if (l->state == LINK_ESTABLISHING)
1183 mtyp = ACTIVATE_MSG;
1184
1185 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
1186
1187 /* Inform peer that this endpoint is going down if applicable */
1188 skb = skb_peek_tail(xmitq);
1189 if (skb && (l->state == LINK_RESET))
1190 msg_set_peer_stopping(buf_msg(skb), 1);
1191}
1192
1193/* tipc_link_build_nack_msg: prepare link nack message for transmission
1194 * Note that sending of broadcast NACK is coordinated among nodes, to
1195 * reduce the risk of NACK storms towards the sender
1196 */
1197static int tipc_link_build_nack_msg(struct tipc_link *l,
1198 struct sk_buff_head *xmitq)
1199{
1200 u32 def_cnt = ++l->stats.deferred_recv;
1201 int match1, match2;
1202
1203 if (link_is_bc_rcvlink(l)) {
1204 match1 = def_cnt & 0xf;
1205 match2 = tipc_own_addr(l->net) & 0xf;
1206 if (match1 == match2)
1207 return TIPC_LINK_SND_STATE;
1208 return 0;
1209 }
1210
1211 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1212 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1213 return 0;
1214}
1215
1216/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1217 * @l: the link that should handle the message
1218 * @skb: TIPC packet
1219 * @xmitq: queue to place packets to be sent after this call
1220 */
1221int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1222 struct sk_buff_head *xmitq)
1223{
1224 struct sk_buff_head *defq = &l->deferdq;
1225 struct tipc_msg *hdr;
1226 u16 seqno, rcv_nxt, win_lim;
1227 int rc = 0;
1228
1229 do {
1230 hdr = buf_msg(skb);
1231 seqno = msg_seqno(hdr);
1232 rcv_nxt = l->rcv_nxt;
1233 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1234
1235 /* Verify and update link state */
1236 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1237 return tipc_link_proto_rcv(l, skb, xmitq);
1238
1239 if (unlikely(!link_is_up(l))) {
1240 if (l->state == LINK_ESTABLISHING)
1241 rc = TIPC_LINK_UP_EVT;
1242 goto drop;
1243 }
1244
1245 /* Don't send probe at next timeout expiration */
1246 l->silent_intv_cnt = 0;
1247
1248 /* Drop if outside receive window */
1249 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1250 l->stats.duplicates++;
1251 goto drop;
1252 }
1253
1254 /* Forward queues and wake up waiting users */
1255 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1256 tipc_link_advance_backlog(l, xmitq);
1257 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1258 link_prepare_wakeup(l);
1259 }
1260
1261 /* Defer delivery if sequence gap */
1262 if (unlikely(seqno != rcv_nxt)) {
1263 __tipc_skb_queue_sorted(defq, seqno, skb);
1264 rc |= tipc_link_build_nack_msg(l, xmitq);
1265 break;
1266 }
1267
1268 /* Deliver packet */
1269 l->rcv_nxt++;
1270 l->stats.recv_pkts++;
1271 if (!tipc_data_input(l, skb, l->inputq))
1272 rc |= tipc_link_input(l, skb, l->inputq);
1273 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1274 rc |= tipc_link_build_state_msg(l, xmitq);
1275 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1276 break;
1277 } while ((skb = __skb_dequeue(defq)));
1278
1279 return rc;
1280drop:
1281 kfree_skb(skb);
1282 return rc;
1283}
1284
1285static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1286 u16 rcvgap, int tolerance, int priority,
1287 struct sk_buff_head *xmitq)
1288{
1289 struct tipc_link *bcl = l->bc_rcvlink;
1290 struct sk_buff *skb;
1291 struct tipc_msg *hdr;
1292 struct sk_buff_head *dfq = &l->deferdq;
1293 bool node_up = link_is_up(bcl);
1294 struct tipc_mon_state *mstate = &l->mon_state;
1295 int dlen = 0;
1296 void *data;
1297
1298 /* Don't send protocol message during reset or link failover */
1299 if (tipc_link_is_blocked(l))
1300 return;
1301
1302 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1303 return;
1304
1305 if (!skb_queue_empty(dfq))
1306 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1307
1308 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1309 tipc_max_domain_size, l->addr,
1310 tipc_own_addr(l->net), 0, 0, 0);
1311 if (!skb)
1312 return;
1313
1314 hdr = buf_msg(skb);
1315 data = msg_data(hdr);
1316 msg_set_session(hdr, l->session);
1317 msg_set_bearer_id(hdr, l->bearer_id);
1318 msg_set_net_plane(hdr, l->net_plane);
1319 msg_set_next_sent(hdr, l->snd_nxt);
1320 msg_set_ack(hdr, l->rcv_nxt - 1);
1321 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1322 msg_set_bc_ack_invalid(hdr, !node_up);
1323 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1324 msg_set_link_tolerance(hdr, tolerance);
1325 msg_set_linkprio(hdr, priority);
1326 msg_set_redundant_link(hdr, node_up);
1327 msg_set_seq_gap(hdr, 0);
1328 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1329
1330 if (mtyp == STATE_MSG) {
1331 msg_set_seq_gap(hdr, rcvgap);
1332 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1333 msg_set_probe(hdr, probe);
1334 tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id);
1335 msg_set_size(hdr, INT_H_SIZE + dlen);
1336 skb_trim(skb, INT_H_SIZE + dlen);
1337 l->stats.sent_states++;
1338 l->rcv_unacked = 0;
1339 } else {
1340 /* RESET_MSG or ACTIVATE_MSG */
1341 msg_set_max_pkt(hdr, l->advertised_mtu);
1342 strcpy(data, l->if_name);
1343 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1344 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1345 }
1346 if (probe)
1347 l->stats.sent_probes++;
1348 if (rcvgap)
1349 l->stats.sent_nacks++;
1350 skb->priority = TC_PRIO_CONTROL;
1351 __skb_queue_tail(xmitq, skb);
1352}
1353
1354/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1355 * with contents of the link's transmit and backlog queues.
1356 */
1357void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1358 int mtyp, struct sk_buff_head *xmitq)
1359{
1360 struct sk_buff *skb, *tnlskb;
1361 struct tipc_msg *hdr, tnlhdr;
1362 struct sk_buff_head *queue = &l->transmq;
1363 struct sk_buff_head tmpxq, tnlq;
1364 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1365
1366 if (!tnl)
1367 return;
1368
1369 skb_queue_head_init(&tnlq);
1370 skb_queue_head_init(&tmpxq);
1371
1372 /* At least one packet required for safe algorithm => add dummy */
1373 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1374 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1375 0, 0, TIPC_ERR_NO_PORT);
1376 if (!skb) {
1377 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1378 return;
1379 }
1380 skb_queue_tail(&tnlq, skb);
1381 tipc_link_xmit(l, &tnlq, &tmpxq);
1382 __skb_queue_purge(&tmpxq);
1383
1384 /* Initialize reusable tunnel packet header */
1385 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1386 mtyp, INT_H_SIZE, l->addr);
1387 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1388 msg_set_msgcnt(&tnlhdr, pktcnt);
1389 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1390tnl:
1391 /* Wrap each packet into a tunnel packet */
1392 skb_queue_walk(queue, skb) {
1393 hdr = buf_msg(skb);
1394 if (queue == &l->backlogq)
1395 msg_set_seqno(hdr, seqno++);
1396 pktlen = msg_size(hdr);
1397 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1398 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
1399 if (!tnlskb) {
1400 pr_warn("%sunable to send packet\n", link_co_err);
1401 return;
1402 }
1403 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1404 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1405 __skb_queue_tail(&tnlq, tnlskb);
1406 }
1407 if (queue != &l->backlogq) {
1408 queue = &l->backlogq;
1409 goto tnl;
1410 }
1411
1412 tipc_link_xmit(tnl, &tnlq, xmitq);
1413
1414 if (mtyp == FAILOVER_MSG) {
1415 tnl->drop_point = l->rcv_nxt;
1416 tnl->failover_reasm_skb = l->reasm_buf;
1417 l->reasm_buf = NULL;
1418 }
1419}
1420
1421/* tipc_link_proto_rcv(): receive link level protocol message :
1422 * Note that network plane id propagates through the network, and may
1423 * change at any time. The node with lowest numerical id determines
1424 * network plane
1425 */
1426static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1427 struct sk_buff_head *xmitq)
1428{
1429 struct tipc_msg *hdr = buf_msg(skb);
1430 u16 rcvgap = 0;
1431 u16 ack = msg_ack(hdr);
1432 u16 gap = msg_seq_gap(hdr);
1433 u16 peers_snd_nxt = msg_next_sent(hdr);
1434 u16 peers_tol = msg_link_tolerance(hdr);
1435 u16 peers_prio = msg_linkprio(hdr);
1436 u16 rcv_nxt = l->rcv_nxt;
1437 u16 dlen = msg_data_sz(hdr);
1438 int mtyp = msg_type(hdr);
1439 void *data;
1440 char *if_name;
1441 int rc = 0;
1442
1443 if (tipc_link_is_blocked(l) || !xmitq)
1444 goto exit;
1445
1446 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1447 l->net_plane = msg_net_plane(hdr);
1448
1449 skb_linearize(skb);
1450 hdr = buf_msg(skb);
1451 data = msg_data(hdr);
1452
1453 switch (mtyp) {
1454 case RESET_MSG:
1455
1456 /* Ignore duplicate RESET with old session number */
1457 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1458 (l->peer_session != ANY_SESSION))
1459 break;
1460 /* fall thru' */
1461
1462 case ACTIVATE_MSG:
1463
1464 /* Complete own link name with peer's interface name */
1465 if_name = strrchr(l->name, ':') + 1;
1466 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1467 break;
1468 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1469 break;
1470 strncpy(if_name, data, TIPC_MAX_IF_NAME);
1471
1472 /* Update own tolerance if peer indicates a non-zero value */
1473 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1474 l->tolerance = peers_tol;
1475
1476 /* Update own priority if peer's priority is higher */
1477 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1478 l->priority = peers_prio;
1479
1480 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1481 if (msg_peer_stopping(hdr))
1482 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1483 else if ((mtyp == RESET_MSG) || !link_is_up(l))
1484 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1485
1486 /* ACTIVATE_MSG takes up link if it was already locally reset */
1487 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1488 rc = TIPC_LINK_UP_EVT;
1489
1490 l->peer_session = msg_session(hdr);
1491 l->peer_bearer_id = msg_bearer_id(hdr);
1492 if (l->mtu > msg_max_pkt(hdr))
1493 l->mtu = msg_max_pkt(hdr);
1494 break;
1495
1496 case STATE_MSG:
1497
1498 /* Update own tolerance if peer indicates a non-zero value */
1499 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1500 l->tolerance = peers_tol;
1501
1502 /* Update own prio if peer indicates a different value */
1503 if ((peers_prio != l->priority) &&
1504 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
1505 l->priority = peers_prio;
1506 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1507 }
1508
1509 l->silent_intv_cnt = 0;
1510 l->stats.recv_states++;
1511 if (msg_probe(hdr))
1512 l->stats.recv_probes++;
1513
1514 if (!link_is_up(l)) {
1515 if (l->state == LINK_ESTABLISHING)
1516 rc = TIPC_LINK_UP_EVT;
1517 break;
1518 }
1519 tipc_mon_rcv(l->net, data, dlen, l->addr,
1520 &l->mon_state, l->bearer_id);
1521
1522 /* Send NACK if peer has sent pkts we haven't received yet */
1523 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1524 rcvgap = peers_snd_nxt - l->rcv_nxt;
1525 if (rcvgap || (msg_probe(hdr)))
1526 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1527 0, 0, xmitq);
1528 tipc_link_release_pkts(l, ack);
1529
1530 /* If NACK, retransmit will now start at right position */
1531 if (gap) {
1532 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1533 l->stats.recv_nacks++;
1534 }
1535
1536 tipc_link_advance_backlog(l, xmitq);
1537 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1538 link_prepare_wakeup(l);
1539 }
1540exit:
1541 kfree_skb(skb);
1542 return rc;
1543}
1544
1545/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1546 */
1547static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1548 u16 peers_snd_nxt,
1549 struct sk_buff_head *xmitq)
1550{
1551 struct sk_buff *skb;
1552 struct tipc_msg *hdr;
1553 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1554 u16 ack = l->rcv_nxt - 1;
1555 u16 gap_to = peers_snd_nxt - 1;
1556
1557 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1558 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
1559 if (!skb)
1560 return false;
1561 hdr = buf_msg(skb);
1562 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1563 msg_set_bcast_ack(hdr, ack);
1564 msg_set_bcgap_after(hdr, ack);
1565 if (dfrd_skb)
1566 gap_to = buf_seqno(dfrd_skb) - 1;
1567 msg_set_bcgap_to(hdr, gap_to);
1568 msg_set_non_seq(hdr, bcast);
1569 __skb_queue_tail(xmitq, skb);
1570 return true;
1571}
1572
1573/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1574 *
1575 * Give a newly added peer node the sequence number where it should
1576 * start receiving and acking broadcast packets.
1577 */
1578static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1579 struct sk_buff_head *xmitq)
1580{
1581 struct sk_buff_head list;
1582
1583 __skb_queue_head_init(&list);
1584 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1585 return;
1586 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
1587 tipc_link_xmit(l, &list, xmitq);
1588}
1589
1590/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1591 */
1592void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1593{
1594 int mtyp = msg_type(hdr);
1595 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1596
1597 if (link_is_up(l))
1598 return;
1599
1600 if (msg_user(hdr) == BCAST_PROTOCOL) {
1601 l->rcv_nxt = peers_snd_nxt;
1602 l->state = LINK_ESTABLISHED;
1603 return;
1604 }
1605
1606 if (l->peer_caps & TIPC_BCAST_SYNCH)
1607 return;
1608
1609 if (msg_peer_node_is_up(hdr))
1610 return;
1611
1612 /* Compatibility: accept older, less safe initial synch data */
1613 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1614 l->rcv_nxt = peers_snd_nxt;
1615}
1616
1617/* link_bc_retr eval()- check if the indicated range can be retransmitted now
1618 * - Adjust permitted range if there is overlap with previous retransmission
1619 */
1620static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to)
1621{
1622 unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr);
1623
1624 if (less(*to, *from))
1625 return false;
1626
1627 /* New retransmission request */
1628 if ((elapsed > TIPC_BC_RETR_LIMIT) ||
1629 less(*to, l->prev_from) || more(*from, l->prev_to)) {
1630 l->prev_from = *from;
1631 l->prev_to = *to;
1632 l->prev_retr = jiffies;
1633 return true;
1634 }
1635
1636 /* Inside range of previous retransmit */
1637 if (!less(*from, l->prev_from) && !more(*to, l->prev_to))
1638 return false;
1639
1640 /* Fully or partially outside previous range => exclude overlap */
1641 if (less(*from, l->prev_from)) {
1642 *to = l->prev_from - 1;
1643 l->prev_from = *from;
1644 }
1645 if (more(*to, l->prev_to)) {
1646 *from = l->prev_to + 1;
1647 l->prev_to = *to;
1648 }
1649 l->prev_retr = jiffies;
1650 return true;
1651}
1652
1653/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1654 */
1655int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1656 struct sk_buff_head *xmitq)
1657{
1658 struct tipc_link *snd_l = l->bc_sndlink;
1659 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1660 u16 from = msg_bcast_ack(hdr) + 1;
1661 u16 to = from + msg_bc_gap(hdr) - 1;
1662 int rc = 0;
1663
1664 if (!link_is_up(l))
1665 return rc;
1666
1667 if (!msg_peer_node_is_up(hdr))
1668 return rc;
1669
1670 /* Open when peer ackowledges our bcast init msg (pkt #1) */
1671 if (msg_ack(hdr))
1672 l->bc_peer_is_up = true;
1673
1674 if (!l->bc_peer_is_up)
1675 return rc;
1676
1677 l->stats.recv_nacks++;
1678
1679 /* Ignore if peers_snd_nxt goes beyond receive window */
1680 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1681 return rc;
1682
1683 if (link_bc_retr_eval(snd_l, &from, &to))
1684 rc = tipc_link_retrans(snd_l, from, to, xmitq);
1685
1686 l->snd_nxt = peers_snd_nxt;
1687 if (link_bc_rcv_gap(l))
1688 rc |= TIPC_LINK_SND_STATE;
1689
1690 /* Return now if sender supports nack via STATE messages */
1691 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
1692 return rc;
1693
1694 /* Otherwise, be backwards compatible */
1695
1696 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1697 l->nack_state = BC_NACK_SND_CONDITIONAL;
1698 return 0;
1699 }
1700
1701 /* Don't NACK if one was recently sent or peeked */
1702 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1703 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1704 return 0;
1705 }
1706
1707 /* Conditionally delay NACK sending until next synch rcv */
1708 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1709 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1710 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1711 return 0;
1712 }
1713
1714 /* Send NACK now but suppress next one */
1715 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1716 l->nack_state = BC_NACK_SND_SUPPRESS;
1717 return 0;
1718}
1719
1720void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1721 struct sk_buff_head *xmitq)
1722{
1723 struct sk_buff *skb, *tmp;
1724 struct tipc_link *snd_l = l->bc_sndlink;
1725
1726 if (!link_is_up(l) || !l->bc_peer_is_up)
1727 return;
1728
1729 if (!more(acked, l->acked))
1730 return;
1731
1732 /* Skip over packets peer has already acked */
1733 skb_queue_walk(&snd_l->transmq, skb) {
1734 if (more(buf_seqno(skb), l->acked))
1735 break;
1736 }
1737
1738 /* Update/release the packets peer is acking now */
1739 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1740 if (more(buf_seqno(skb), acked))
1741 break;
1742 if (!--TIPC_SKB_CB(skb)->ackers) {
1743 __skb_unlink(skb, &snd_l->transmq);
1744 kfree_skb(skb);
1745 }
1746 }
1747 l->acked = acked;
1748 tipc_link_advance_backlog(snd_l, xmitq);
1749 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1750 link_prepare_wakeup(snd_l);
1751}
1752
1753/* tipc_link_bc_nack_rcv(): receive broadcast nack message
1754 * This function is here for backwards compatibility, since
1755 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
1756 */
1757int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1758 struct sk_buff_head *xmitq)
1759{
1760 struct tipc_msg *hdr = buf_msg(skb);
1761 u32 dnode = msg_destnode(hdr);
1762 int mtyp = msg_type(hdr);
1763 u16 acked = msg_bcast_ack(hdr);
1764 u16 from = acked + 1;
1765 u16 to = msg_bcgap_to(hdr);
1766 u16 peers_snd_nxt = to + 1;
1767 int rc = 0;
1768
1769 kfree_skb(skb);
1770
1771 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1772 return 0;
1773
1774 if (mtyp != STATE_MSG)
1775 return 0;
1776
1777 if (dnode == tipc_own_addr(l->net)) {
1778 tipc_link_bc_ack_rcv(l, acked, xmitq);
1779 rc = tipc_link_retrans(l->bc_sndlink, from, to, xmitq);
1780 l->stats.recv_nacks++;
1781 return rc;
1782 }
1783
1784 /* Msg for other node => suppress own NACK at next sync if applicable */
1785 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1786 l->nack_state = BC_NACK_SND_SUPPRESS;
1787
1788 return 0;
1789}
1790
1791void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1792{
1793 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1794
1795 l->window = win;
1796 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win);
1797 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2);
1798 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3);
1799 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4);
1800 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1801}
1802
1803/**
1804 * link_reset_stats - reset link statistics
1805 * @l: pointer to link
1806 */
1807void tipc_link_reset_stats(struct tipc_link *l)
1808{
1809 memset(&l->stats, 0, sizeof(l->stats));
1810}
1811
1812static void link_print(struct tipc_link *l, const char *str)
1813{
1814 struct sk_buff *hskb = skb_peek(&l->transmq);
1815 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1816 u16 tail = l->snd_nxt - 1;
1817
1818 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1819 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1820 skb_queue_len(&l->transmq), head, tail,
1821 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1822}
1823
1824/* Parse and validate nested (link) properties valid for media, bearer and link
1825 */
1826int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1827{
1828 int err;
1829
1830 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1831 tipc_nl_prop_policy);
1832 if (err)
1833 return err;
1834
1835 if (props[TIPC_NLA_PROP_PRIO]) {
1836 u32 prio;
1837
1838 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1839 if (prio > TIPC_MAX_LINK_PRI)
1840 return -EINVAL;
1841 }
1842
1843 if (props[TIPC_NLA_PROP_TOL]) {
1844 u32 tol;
1845
1846 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1847 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1848 return -EINVAL;
1849 }
1850
1851 if (props[TIPC_NLA_PROP_WIN]) {
1852 u32 win;
1853
1854 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1855 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1856 return -EINVAL;
1857 }
1858
1859 return 0;
1860}
1861
1862static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1863{
1864 int i;
1865 struct nlattr *stats;
1866
1867 struct nla_map {
1868 u32 key;
1869 u32 val;
1870 };
1871
1872 struct nla_map map[] = {
1873 {TIPC_NLA_STATS_RX_INFO, 0},
1874 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1875 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1876 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1877 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1878 {TIPC_NLA_STATS_TX_INFO, 0},
1879 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1880 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1881 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1882 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1883 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1884 s->msg_length_counts : 1},
1885 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1886 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1887 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1888 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1889 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1890 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1891 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1892 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1893 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1894 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1895 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1896 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1897 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1898 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1899 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1900 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1901 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1902 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1903 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1904 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1905 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1906 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1907 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1908 };
1909
1910 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1911 if (!stats)
1912 return -EMSGSIZE;
1913
1914 for (i = 0; i < ARRAY_SIZE(map); i++)
1915 if (nla_put_u32(skb, map[i].key, map[i].val))
1916 goto msg_full;
1917
1918 nla_nest_end(skb, stats);
1919
1920 return 0;
1921msg_full:
1922 nla_nest_cancel(skb, stats);
1923
1924 return -EMSGSIZE;
1925}
1926
1927/* Caller should hold appropriate locks to protect the link */
1928int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1929 struct tipc_link *link, int nlflags)
1930{
1931 int err;
1932 void *hdr;
1933 struct nlattr *attrs;
1934 struct nlattr *prop;
1935 struct tipc_net *tn = net_generic(net, tipc_net_id);
1936
1937 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1938 nlflags, TIPC_NL_LINK_GET);
1939 if (!hdr)
1940 return -EMSGSIZE;
1941
1942 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1943 if (!attrs)
1944 goto msg_full;
1945
1946 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1947 goto attr_msg_full;
1948 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1949 tipc_cluster_mask(tn->own_addr)))
1950 goto attr_msg_full;
1951 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1952 goto attr_msg_full;
1953 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
1954 goto attr_msg_full;
1955 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
1956 goto attr_msg_full;
1957
1958 if (tipc_link_is_up(link))
1959 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1960 goto attr_msg_full;
1961 if (link->active)
1962 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1963 goto attr_msg_full;
1964
1965 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1966 if (!prop)
1967 goto attr_msg_full;
1968 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1969 goto prop_msg_full;
1970 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1971 goto prop_msg_full;
1972 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1973 link->window))
1974 goto prop_msg_full;
1975 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1976 goto prop_msg_full;
1977 nla_nest_end(msg->skb, prop);
1978
1979 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1980 if (err)
1981 goto attr_msg_full;
1982
1983 nla_nest_end(msg->skb, attrs);
1984 genlmsg_end(msg->skb, hdr);
1985
1986 return 0;
1987
1988prop_msg_full:
1989 nla_nest_cancel(msg->skb, prop);
1990attr_msg_full:
1991 nla_nest_cancel(msg->skb, attrs);
1992msg_full:
1993 genlmsg_cancel(msg->skb, hdr);
1994
1995 return -EMSGSIZE;
1996}
1997
1998static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
1999 struct tipc_stats *stats)
2000{
2001 int i;
2002 struct nlattr *nest;
2003
2004 struct nla_map {
2005 __u32 key;
2006 __u32 val;
2007 };
2008
2009 struct nla_map map[] = {
2010 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2011 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2012 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2013 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2014 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2015 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2016 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2017 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2018 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2019 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2020 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2021 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2022 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2023 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2024 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2025 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2026 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2027 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2028 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2029 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2030 };
2031
2032 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
2033 if (!nest)
2034 return -EMSGSIZE;
2035
2036 for (i = 0; i < ARRAY_SIZE(map); i++)
2037 if (nla_put_u32(skb, map[i].key, map[i].val))
2038 goto msg_full;
2039
2040 nla_nest_end(skb, nest);
2041
2042 return 0;
2043msg_full:
2044 nla_nest_cancel(skb, nest);
2045
2046 return -EMSGSIZE;
2047}
2048
2049int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
2050{
2051 int err;
2052 void *hdr;
2053 struct nlattr *attrs;
2054 struct nlattr *prop;
2055 struct tipc_net *tn = net_generic(net, tipc_net_id);
2056 struct tipc_link *bcl = tn->bcl;
2057
2058 if (!bcl)
2059 return 0;
2060
2061 tipc_bcast_lock(net);
2062
2063 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2064 NLM_F_MULTI, TIPC_NL_LINK_GET);
2065 if (!hdr) {
2066 tipc_bcast_unlock(net);
2067 return -EMSGSIZE;
2068 }
2069
2070 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2071 if (!attrs)
2072 goto msg_full;
2073
2074 /* The broadcast link is always up */
2075 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2076 goto attr_msg_full;
2077
2078 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2079 goto attr_msg_full;
2080 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2081 goto attr_msg_full;
2082 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2083 goto attr_msg_full;
2084 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2085 goto attr_msg_full;
2086
2087 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2088 if (!prop)
2089 goto attr_msg_full;
2090 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
2091 goto prop_msg_full;
2092 nla_nest_end(msg->skb, prop);
2093
2094 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2095 if (err)
2096 goto attr_msg_full;
2097
2098 tipc_bcast_unlock(net);
2099 nla_nest_end(msg->skb, attrs);
2100 genlmsg_end(msg->skb, hdr);
2101
2102 return 0;
2103
2104prop_msg_full:
2105 nla_nest_cancel(msg->skb, prop);
2106attr_msg_full:
2107 nla_nest_cancel(msg->skb, attrs);
2108msg_full:
2109 tipc_bcast_unlock(net);
2110 genlmsg_cancel(msg->skb, hdr);
2111
2112 return -EMSGSIZE;
2113}
2114
2115void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2116 struct sk_buff_head *xmitq)
2117{
2118 l->tolerance = tol;
2119 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, tol, 0, xmitq);
2120}
2121
2122void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2123 struct sk_buff_head *xmitq)
2124{
2125 l->priority = prio;
2126 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, prio, xmitq);
2127}
2128
2129void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2130{
2131 l->abort_limit = limit;
2132}