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1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "subscr.h"
39#include "link.h"
40#include "bcast.h"
41#include "socket.h"
42#include "name_distr.h"
43#include "discover.h"
44#include "netlink.h"
45#include "monitor.h"
46#include "trace.h"
47#include "crypto.h"
48
49#include <linux/pkt_sched.h>
50
51struct tipc_stats {
52 u32 sent_pkts;
53 u32 recv_pkts;
54 u32 sent_states;
55 u32 recv_states;
56 u32 sent_probes;
57 u32 recv_probes;
58 u32 sent_nacks;
59 u32 recv_nacks;
60 u32 sent_acks;
61 u32 sent_bundled;
62 u32 sent_bundles;
63 u32 recv_bundled;
64 u32 recv_bundles;
65 u32 retransmitted;
66 u32 sent_fragmented;
67 u32 sent_fragments;
68 u32 recv_fragmented;
69 u32 recv_fragments;
70 u32 link_congs; /* # port sends blocked by congestion */
71 u32 deferred_recv;
72 u32 duplicates;
73 u32 max_queue_sz; /* send queue size high water mark */
74 u32 accu_queue_sz; /* used for send queue size profiling */
75 u32 queue_sz_counts; /* used for send queue size profiling */
76 u32 msg_length_counts; /* used for message length profiling */
77 u32 msg_lengths_total; /* used for message length profiling */
78 u32 msg_length_profile[7]; /* used for msg. length profiling */
79};
80
81/**
82 * struct tipc_link - TIPC link data structure
83 * @addr: network address of link's peer node
84 * @name: link name character string
85 * @media_addr: media address to use when sending messages over link
86 * @timer: link timer
87 * @net: pointer to namespace struct
88 * @refcnt: reference counter for permanent references (owner node & timer)
89 * @peer_session: link session # being used by peer end of link
90 * @peer_bearer_id: bearer id used by link's peer endpoint
91 * @bearer_id: local bearer id used by link
92 * @tolerance: minimum link continuity loss needed to reset link [in ms]
93 * @abort_limit: # of unacknowledged continuity probes needed to reset link
94 * @state: current state of link FSM
95 * @peer_caps: bitmap describing capabilities of peer node
96 * @silent_intv_cnt: # of timer intervals without any reception from peer
97 * @proto_msg: template for control messages generated by link
98 * @pmsg: convenience pointer to "proto_msg" field
99 * @priority: current link priority
100 * @net_plane: current link network plane ('A' through 'H')
101 * @mon_state: cookie with information needed by link monitor
102 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
103 * @exp_msg_count: # of tunnelled messages expected during link changeover
104 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
105 * @mtu: current maximum packet size for this link
106 * @advertised_mtu: advertised own mtu when link is being established
107 * @transmitq: queue for sent, non-acked messages
108 * @backlogq: queue for messages waiting to be sent
109 * @snt_nxt: next sequence number to use for outbound messages
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 * @session: session to be used by link
124 * @snd_nxt_state: next send seq number
125 * @rcv_nxt_state: next rcv seq number
126 * @in_session: have received ACTIVATE_MSG from peer
127 * @active: link is active
128 * @if_name: associated interface name
129 * @rst_cnt: link reset counter
130 * @drop_point: seq number for failover handling (FIXME)
131 * @failover_reasm_skb: saved failover msg ptr (FIXME)
132 * @failover_deferdq: deferred message queue for failover processing (FIXME)
133 * @transmq: the link's transmit queue
134 * @backlog: link's backlog by priority (importance)
135 * @snd_nxt: next sequence number to be used
136 * @rcv_unacked: # messages read by user, but not yet acked back to peer
137 * @deferdq: deferred receive queue
138 * @window: sliding window size for congestion handling
139 * @min_win: minimal send window to be used by link
140 * @ssthresh: slow start threshold for congestion handling
141 * @max_win: maximal send window to be used by link
142 * @cong_acks: congestion acks for congestion avoidance (FIXME)
143 * @checkpoint: seq number for congestion window size handling
144 * @reasm_tnlmsg: fragmentation/reassembly area for tunnel protocol message
145 * @last_gap: last gap ack blocks for bcast (FIXME)
146 * @last_ga: ptr to gap ack blocks
147 * @bc_rcvlink: the peer specific link used for broadcast reception
148 * @bc_sndlink: the namespace global link used for broadcast sending
149 * @nack_state: bcast nack state
150 * @bc_peer_is_up: peer has acked the bcast init msg
151 */
152struct tipc_link {
153 u32 addr;
154 char name[TIPC_MAX_LINK_NAME];
155 struct net *net;
156
157 /* Management and link supervision data */
158 u16 peer_session;
159 u16 session;
160 u16 snd_nxt_state;
161 u16 rcv_nxt_state;
162 u32 peer_bearer_id;
163 u32 bearer_id;
164 u32 tolerance;
165 u32 abort_limit;
166 u32 state;
167 u16 peer_caps;
168 bool in_session;
169 bool active;
170 u32 silent_intv_cnt;
171 char if_name[TIPC_MAX_IF_NAME];
172 u32 priority;
173 char net_plane;
174 struct tipc_mon_state mon_state;
175 u16 rst_cnt;
176
177 /* Failover/synch */
178 u16 drop_point;
179 struct sk_buff *failover_reasm_skb;
180 struct sk_buff_head failover_deferdq;
181
182 /* Max packet negotiation */
183 u16 mtu;
184 u16 advertised_mtu;
185
186 /* Sending */
187 struct sk_buff_head transmq;
188 struct sk_buff_head backlogq;
189 struct {
190 u16 len;
191 u16 limit;
192 struct sk_buff *target_bskb;
193 } backlog[5];
194 u16 snd_nxt;
195
196 /* Reception */
197 u16 rcv_nxt;
198 u32 rcv_unacked;
199 struct sk_buff_head deferdq;
200 struct sk_buff_head *inputq;
201 struct sk_buff_head *namedq;
202
203 /* Congestion handling */
204 struct sk_buff_head wakeupq;
205 u16 window;
206 u16 min_win;
207 u16 ssthresh;
208 u16 max_win;
209 u16 cong_acks;
210 u16 checkpoint;
211
212 /* Fragmentation/reassembly */
213 struct sk_buff *reasm_buf;
214 struct sk_buff *reasm_tnlmsg;
215
216 /* Broadcast */
217 u16 ackers;
218 u16 acked;
219 u16 last_gap;
220 struct tipc_gap_ack_blks *last_ga;
221 struct tipc_link *bc_rcvlink;
222 struct tipc_link *bc_sndlink;
223 u8 nack_state;
224 bool bc_peer_is_up;
225
226 /* Statistics */
227 struct tipc_stats stats;
228};
229
230/*
231 * Error message prefixes
232 */
233static const char *link_co_err = "Link tunneling error, ";
234static const char *link_rst_msg = "Resetting link ";
235
236/* Send states for broadcast NACKs
237 */
238enum {
239 BC_NACK_SND_CONDITIONAL,
240 BC_NACK_SND_UNCONDITIONAL,
241 BC_NACK_SND_SUPPRESS,
242};
243
244#define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
245#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
246
247/* Link FSM states:
248 */
249enum {
250 LINK_ESTABLISHED = 0xe,
251 LINK_ESTABLISHING = 0xe << 4,
252 LINK_RESET = 0x1 << 8,
253 LINK_RESETTING = 0x2 << 12,
254 LINK_PEER_RESET = 0xd << 16,
255 LINK_FAILINGOVER = 0xf << 20,
256 LINK_SYNCHING = 0xc << 24
257};
258
259/* Link FSM state checking routines
260 */
261static int link_is_up(struct tipc_link *l)
262{
263 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
264}
265
266static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
267 struct sk_buff_head *xmitq);
268static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
269 bool probe_reply, u16 rcvgap,
270 int tolerance, int priority,
271 struct sk_buff_head *xmitq);
272static void link_print(struct tipc_link *l, const char *str);
273static int tipc_link_build_nack_msg(struct tipc_link *l,
274 struct sk_buff_head *xmitq);
275static void tipc_link_build_bc_init_msg(struct tipc_link *l,
276 struct sk_buff_head *xmitq);
277static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
278 struct tipc_link *l, u8 start_index);
279static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
280static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
281 u16 acked, u16 gap,
282 struct tipc_gap_ack_blks *ga,
283 struct sk_buff_head *xmitq,
284 bool *retransmitted, int *rc);
285static void tipc_link_update_cwin(struct tipc_link *l, int released,
286 bool retransmitted);
287/*
288 * Simple non-static link routines (i.e. referenced outside this file)
289 */
290bool tipc_link_is_up(struct tipc_link *l)
291{
292 return link_is_up(l);
293}
294
295bool tipc_link_peer_is_down(struct tipc_link *l)
296{
297 return l->state == LINK_PEER_RESET;
298}
299
300bool tipc_link_is_reset(struct tipc_link *l)
301{
302 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
303}
304
305bool tipc_link_is_establishing(struct tipc_link *l)
306{
307 return l->state == LINK_ESTABLISHING;
308}
309
310bool tipc_link_is_synching(struct tipc_link *l)
311{
312 return l->state == LINK_SYNCHING;
313}
314
315bool tipc_link_is_failingover(struct tipc_link *l)
316{
317 return l->state == LINK_FAILINGOVER;
318}
319
320bool tipc_link_is_blocked(struct tipc_link *l)
321{
322 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
323}
324
325static bool link_is_bc_sndlink(struct tipc_link *l)
326{
327 return !l->bc_sndlink;
328}
329
330static bool link_is_bc_rcvlink(struct tipc_link *l)
331{
332 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
333}
334
335void tipc_link_set_active(struct tipc_link *l, bool active)
336{
337 l->active = active;
338}
339
340u32 tipc_link_id(struct tipc_link *l)
341{
342 return l->peer_bearer_id << 16 | l->bearer_id;
343}
344
345int tipc_link_min_win(struct tipc_link *l)
346{
347 return l->min_win;
348}
349
350int tipc_link_max_win(struct tipc_link *l)
351{
352 return l->max_win;
353}
354
355int tipc_link_prio(struct tipc_link *l)
356{
357 return l->priority;
358}
359
360unsigned long tipc_link_tolerance(struct tipc_link *l)
361{
362 return l->tolerance;
363}
364
365struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
366{
367 return l->inputq;
368}
369
370char tipc_link_plane(struct tipc_link *l)
371{
372 return l->net_plane;
373}
374
375struct net *tipc_link_net(struct tipc_link *l)
376{
377 return l->net;
378}
379
380void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
381{
382 l->peer_caps = capabilities;
383}
384
385void tipc_link_add_bc_peer(struct tipc_link *snd_l,
386 struct tipc_link *uc_l,
387 struct sk_buff_head *xmitq)
388{
389 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
390
391 snd_l->ackers++;
392 rcv_l->acked = snd_l->snd_nxt - 1;
393 snd_l->state = LINK_ESTABLISHED;
394 tipc_link_build_bc_init_msg(uc_l, xmitq);
395}
396
397void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
398 struct tipc_link *rcv_l,
399 struct sk_buff_head *xmitq)
400{
401 u16 ack = snd_l->snd_nxt - 1;
402
403 snd_l->ackers--;
404 rcv_l->bc_peer_is_up = true;
405 rcv_l->state = LINK_ESTABLISHED;
406 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
407 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
408 tipc_link_reset(rcv_l);
409 rcv_l->state = LINK_RESET;
410 if (!snd_l->ackers) {
411 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
412 tipc_link_reset(snd_l);
413 snd_l->state = LINK_RESET;
414 __skb_queue_purge(xmitq);
415 }
416}
417
418int tipc_link_bc_peers(struct tipc_link *l)
419{
420 return l->ackers;
421}
422
423static u16 link_bc_rcv_gap(struct tipc_link *l)
424{
425 struct sk_buff *skb = skb_peek(&l->deferdq);
426 u16 gap = 0;
427
428 if (more(l->snd_nxt, l->rcv_nxt))
429 gap = l->snd_nxt - l->rcv_nxt;
430 if (skb)
431 gap = buf_seqno(skb) - l->rcv_nxt;
432 return gap;
433}
434
435void tipc_link_set_mtu(struct tipc_link *l, int mtu)
436{
437 l->mtu = mtu;
438}
439
440int tipc_link_mtu(struct tipc_link *l)
441{
442 return l->mtu;
443}
444
445int tipc_link_mss(struct tipc_link *l)
446{
447#ifdef CONFIG_TIPC_CRYPTO
448 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
449#else
450 return l->mtu - INT_H_SIZE;
451#endif
452}
453
454u16 tipc_link_rcv_nxt(struct tipc_link *l)
455{
456 return l->rcv_nxt;
457}
458
459u16 tipc_link_acked(struct tipc_link *l)
460{
461 return l->acked;
462}
463
464char *tipc_link_name(struct tipc_link *l)
465{
466 return l->name;
467}
468
469u32 tipc_link_state(struct tipc_link *l)
470{
471 return l->state;
472}
473
474/**
475 * tipc_link_create - create a new link
476 * @net: pointer to associated network namespace
477 * @if_name: associated interface name
478 * @bearer_id: id (index) of associated bearer
479 * @tolerance: link tolerance to be used by link
480 * @net_plane: network plane (A,B,c..) this link belongs to
481 * @mtu: mtu to be advertised by link
482 * @priority: priority to be used by link
483 * @min_win: minimal send window to be used by link
484 * @max_win: maximal send window to be used by link
485 * @session: session to be used by link
486 * @peer: node id of peer node
487 * @peer_caps: bitmap describing peer node capabilities
488 * @bc_sndlink: the namespace global link used for broadcast sending
489 * @bc_rcvlink: the peer specific link used for broadcast reception
490 * @inputq: queue to put messages ready for delivery
491 * @namedq: queue to put binding table update messages ready for delivery
492 * @link: return value, pointer to put the created link
493 * @self: local unicast link id
494 * @peer_id: 128-bit ID of peer
495 *
496 * Return: true if link was created, otherwise false
497 */
498bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
499 int tolerance, char net_plane, u32 mtu, int priority,
500 u32 min_win, u32 max_win, u32 session, u32 self,
501 u32 peer, u8 *peer_id, u16 peer_caps,
502 struct tipc_link *bc_sndlink,
503 struct tipc_link *bc_rcvlink,
504 struct sk_buff_head *inputq,
505 struct sk_buff_head *namedq,
506 struct tipc_link **link)
507{
508 char peer_str[NODE_ID_STR_LEN] = {0,};
509 char self_str[NODE_ID_STR_LEN] = {0,};
510 struct tipc_link *l;
511
512 l = kzalloc(sizeof(*l), GFP_ATOMIC);
513 if (!l)
514 return false;
515 *link = l;
516 l->session = session;
517
518 /* Set link name for unicast links only */
519 if (peer_id) {
520 tipc_nodeid2string(self_str, tipc_own_id(net));
521 if (strlen(self_str) > 16)
522 sprintf(self_str, "%x", self);
523 tipc_nodeid2string(peer_str, peer_id);
524 if (strlen(peer_str) > 16)
525 sprintf(peer_str, "%x", peer);
526 }
527 /* Peer i/f name will be completed by reset/activate message */
528 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
529 self_str, if_name, peer_str);
530
531 strcpy(l->if_name, if_name);
532 l->addr = peer;
533 l->peer_caps = peer_caps;
534 l->net = net;
535 l->in_session = false;
536 l->bearer_id = bearer_id;
537 l->tolerance = tolerance;
538 if (bc_rcvlink)
539 bc_rcvlink->tolerance = tolerance;
540 l->net_plane = net_plane;
541 l->advertised_mtu = mtu;
542 l->mtu = mtu;
543 l->priority = priority;
544 tipc_link_set_queue_limits(l, min_win, max_win);
545 l->ackers = 1;
546 l->bc_sndlink = bc_sndlink;
547 l->bc_rcvlink = bc_rcvlink;
548 l->inputq = inputq;
549 l->namedq = namedq;
550 l->state = LINK_RESETTING;
551 __skb_queue_head_init(&l->transmq);
552 __skb_queue_head_init(&l->backlogq);
553 __skb_queue_head_init(&l->deferdq);
554 __skb_queue_head_init(&l->failover_deferdq);
555 skb_queue_head_init(&l->wakeupq);
556 skb_queue_head_init(l->inputq);
557 return true;
558}
559
560/**
561 * tipc_link_bc_create - create new link to be used for broadcast
562 * @net: pointer to associated network namespace
563 * @mtu: mtu to be used initially if no peers
564 * @min_win: minimal send window to be used by link
565 * @max_win: maximal send window to be used by link
566 * @inputq: queue to put messages ready for delivery
567 * @namedq: queue to put binding table update messages ready for delivery
568 * @link: return value, pointer to put the created link
569 * @ownnode: identity of own node
570 * @peer: node id of peer node
571 * @peer_id: 128-bit ID of peer
572 * @peer_caps: bitmap describing peer node capabilities
573 * @bc_sndlink: the namespace global link used for broadcast sending
574 *
575 * Return: true if link was created, otherwise false
576 */
577bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
578 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
579 struct sk_buff_head *inputq,
580 struct sk_buff_head *namedq,
581 struct tipc_link *bc_sndlink,
582 struct tipc_link **link)
583{
584 struct tipc_link *l;
585
586 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
587 max_win, 0, ownnode, peer, NULL, peer_caps,
588 bc_sndlink, NULL, inputq, namedq, link))
589 return false;
590
591 l = *link;
592 if (peer_id) {
593 char peer_str[NODE_ID_STR_LEN] = {0,};
594
595 tipc_nodeid2string(peer_str, peer_id);
596 if (strlen(peer_str) > 16)
597 sprintf(peer_str, "%x", peer);
598 /* Broadcast receiver link name: "broadcast-link:<peer>" */
599 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
600 peer_str);
601 } else {
602 strcpy(l->name, tipc_bclink_name);
603 }
604 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
605 tipc_link_reset(l);
606 l->state = LINK_RESET;
607 l->ackers = 0;
608 l->bc_rcvlink = l;
609
610 /* Broadcast send link is always up */
611 if (link_is_bc_sndlink(l))
612 l->state = LINK_ESTABLISHED;
613
614 /* Disable replicast if even a single peer doesn't support it */
615 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
616 tipc_bcast_toggle_rcast(net, false);
617
618 return true;
619}
620
621/**
622 * tipc_link_fsm_evt - link finite state machine
623 * @l: pointer to link
624 * @evt: state machine event to be processed
625 */
626int tipc_link_fsm_evt(struct tipc_link *l, int evt)
627{
628 int rc = 0;
629 int old_state = l->state;
630
631 switch (l->state) {
632 case LINK_RESETTING:
633 switch (evt) {
634 case LINK_PEER_RESET_EVT:
635 l->state = LINK_PEER_RESET;
636 break;
637 case LINK_RESET_EVT:
638 l->state = LINK_RESET;
639 break;
640 case LINK_FAILURE_EVT:
641 case LINK_FAILOVER_BEGIN_EVT:
642 case LINK_ESTABLISH_EVT:
643 case LINK_FAILOVER_END_EVT:
644 case LINK_SYNCH_BEGIN_EVT:
645 case LINK_SYNCH_END_EVT:
646 default:
647 goto illegal_evt;
648 }
649 break;
650 case LINK_RESET:
651 switch (evt) {
652 case LINK_PEER_RESET_EVT:
653 l->state = LINK_ESTABLISHING;
654 break;
655 case LINK_FAILOVER_BEGIN_EVT:
656 l->state = LINK_FAILINGOVER;
657 break;
658 case LINK_FAILURE_EVT:
659 case LINK_RESET_EVT:
660 case LINK_ESTABLISH_EVT:
661 case LINK_FAILOVER_END_EVT:
662 break;
663 case LINK_SYNCH_BEGIN_EVT:
664 case LINK_SYNCH_END_EVT:
665 default:
666 goto illegal_evt;
667 }
668 break;
669 case LINK_PEER_RESET:
670 switch (evt) {
671 case LINK_RESET_EVT:
672 l->state = LINK_ESTABLISHING;
673 break;
674 case LINK_PEER_RESET_EVT:
675 case LINK_ESTABLISH_EVT:
676 case LINK_FAILURE_EVT:
677 break;
678 case LINK_SYNCH_BEGIN_EVT:
679 case LINK_SYNCH_END_EVT:
680 case LINK_FAILOVER_BEGIN_EVT:
681 case LINK_FAILOVER_END_EVT:
682 default:
683 goto illegal_evt;
684 }
685 break;
686 case LINK_FAILINGOVER:
687 switch (evt) {
688 case LINK_FAILOVER_END_EVT:
689 l->state = LINK_RESET;
690 break;
691 case LINK_PEER_RESET_EVT:
692 case LINK_RESET_EVT:
693 case LINK_ESTABLISH_EVT:
694 case LINK_FAILURE_EVT:
695 break;
696 case LINK_FAILOVER_BEGIN_EVT:
697 case LINK_SYNCH_BEGIN_EVT:
698 case LINK_SYNCH_END_EVT:
699 default:
700 goto illegal_evt;
701 }
702 break;
703 case LINK_ESTABLISHING:
704 switch (evt) {
705 case LINK_ESTABLISH_EVT:
706 l->state = LINK_ESTABLISHED;
707 break;
708 case LINK_FAILOVER_BEGIN_EVT:
709 l->state = LINK_FAILINGOVER;
710 break;
711 case LINK_RESET_EVT:
712 l->state = LINK_RESET;
713 break;
714 case LINK_FAILURE_EVT:
715 case LINK_PEER_RESET_EVT:
716 case LINK_SYNCH_BEGIN_EVT:
717 case LINK_FAILOVER_END_EVT:
718 break;
719 case LINK_SYNCH_END_EVT:
720 default:
721 goto illegal_evt;
722 }
723 break;
724 case LINK_ESTABLISHED:
725 switch (evt) {
726 case LINK_PEER_RESET_EVT:
727 l->state = LINK_PEER_RESET;
728 rc |= TIPC_LINK_DOWN_EVT;
729 break;
730 case LINK_FAILURE_EVT:
731 l->state = LINK_RESETTING;
732 rc |= TIPC_LINK_DOWN_EVT;
733 break;
734 case LINK_RESET_EVT:
735 l->state = LINK_RESET;
736 break;
737 case LINK_ESTABLISH_EVT:
738 case LINK_SYNCH_END_EVT:
739 break;
740 case LINK_SYNCH_BEGIN_EVT:
741 l->state = LINK_SYNCHING;
742 break;
743 case LINK_FAILOVER_BEGIN_EVT:
744 case LINK_FAILOVER_END_EVT:
745 default:
746 goto illegal_evt;
747 }
748 break;
749 case LINK_SYNCHING:
750 switch (evt) {
751 case LINK_PEER_RESET_EVT:
752 l->state = LINK_PEER_RESET;
753 rc |= TIPC_LINK_DOWN_EVT;
754 break;
755 case LINK_FAILURE_EVT:
756 l->state = LINK_RESETTING;
757 rc |= TIPC_LINK_DOWN_EVT;
758 break;
759 case LINK_RESET_EVT:
760 l->state = LINK_RESET;
761 break;
762 case LINK_ESTABLISH_EVT:
763 case LINK_SYNCH_BEGIN_EVT:
764 break;
765 case LINK_SYNCH_END_EVT:
766 l->state = LINK_ESTABLISHED;
767 break;
768 case LINK_FAILOVER_BEGIN_EVT:
769 case LINK_FAILOVER_END_EVT:
770 default:
771 goto illegal_evt;
772 }
773 break;
774 default:
775 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
776 }
777 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
778 return rc;
779illegal_evt:
780 pr_err("Illegal FSM event %x in state %x on link %s\n",
781 evt, l->state, l->name);
782 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
783 return rc;
784}
785
786/* link_profile_stats - update statistical profiling of traffic
787 */
788static void link_profile_stats(struct tipc_link *l)
789{
790 struct sk_buff *skb;
791 struct tipc_msg *msg;
792 int length;
793
794 /* Update counters used in statistical profiling of send traffic */
795 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
796 l->stats.queue_sz_counts++;
797
798 skb = skb_peek(&l->transmq);
799 if (!skb)
800 return;
801 msg = buf_msg(skb);
802 length = msg_size(msg);
803
804 if (msg_user(msg) == MSG_FRAGMENTER) {
805 if (msg_type(msg) != FIRST_FRAGMENT)
806 return;
807 length = msg_size(msg_inner_hdr(msg));
808 }
809 l->stats.msg_lengths_total += length;
810 l->stats.msg_length_counts++;
811 if (length <= 64)
812 l->stats.msg_length_profile[0]++;
813 else if (length <= 256)
814 l->stats.msg_length_profile[1]++;
815 else if (length <= 1024)
816 l->stats.msg_length_profile[2]++;
817 else if (length <= 4096)
818 l->stats.msg_length_profile[3]++;
819 else if (length <= 16384)
820 l->stats.msg_length_profile[4]++;
821 else if (length <= 32768)
822 l->stats.msg_length_profile[5]++;
823 else
824 l->stats.msg_length_profile[6]++;
825}
826
827/**
828 * tipc_link_too_silent - check if link is "too silent"
829 * @l: tipc link to be checked
830 *
831 * Return: true if the link 'silent_intv_cnt' is about to reach the
832 * 'abort_limit' value, otherwise false
833 */
834bool tipc_link_too_silent(struct tipc_link *l)
835{
836 return (l->silent_intv_cnt + 2 > l->abort_limit);
837}
838
839/* tipc_link_timeout - perform periodic task as instructed from node timeout
840 */
841int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
842{
843 int mtyp = 0;
844 int rc = 0;
845 bool state = false;
846 bool probe = false;
847 bool setup = false;
848 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
849 u16 bc_acked = l->bc_rcvlink->acked;
850 struct tipc_mon_state *mstate = &l->mon_state;
851
852 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
853 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
854 switch (l->state) {
855 case LINK_ESTABLISHED:
856 case LINK_SYNCHING:
857 mtyp = STATE_MSG;
858 link_profile_stats(l);
859 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
860 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
861 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
862 state = bc_acked != bc_snt;
863 state |= l->bc_rcvlink->rcv_unacked;
864 state |= l->rcv_unacked;
865 state |= !skb_queue_empty(&l->transmq);
866 probe = mstate->probing;
867 probe |= l->silent_intv_cnt;
868 if (probe || mstate->monitoring)
869 l->silent_intv_cnt++;
870 probe |= !skb_queue_empty(&l->deferdq);
871 if (l->snd_nxt == l->checkpoint) {
872 tipc_link_update_cwin(l, 0, 0);
873 probe = true;
874 }
875 l->checkpoint = l->snd_nxt;
876 break;
877 case LINK_RESET:
878 setup = l->rst_cnt++ <= 4;
879 setup |= !(l->rst_cnt % 16);
880 mtyp = RESET_MSG;
881 break;
882 case LINK_ESTABLISHING:
883 setup = true;
884 mtyp = ACTIVATE_MSG;
885 break;
886 case LINK_PEER_RESET:
887 case LINK_RESETTING:
888 case LINK_FAILINGOVER:
889 break;
890 default:
891 break;
892 }
893
894 if (state || probe || setup)
895 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
896
897 return rc;
898}
899
900/**
901 * link_schedule_user - schedule a message sender for wakeup after congestion
902 * @l: congested link
903 * @hdr: header of message that is being sent
904 * Create pseudo msg to send back to user when congestion abates
905 */
906static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
907{
908 u32 dnode = tipc_own_addr(l->net);
909 u32 dport = msg_origport(hdr);
910 struct sk_buff *skb;
911
912 /* Create and schedule wakeup pseudo message */
913 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
914 dnode, l->addr, dport, 0, 0);
915 if (!skb)
916 return -ENOBUFS;
917 msg_set_dest_droppable(buf_msg(skb), true);
918 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
919 skb_queue_tail(&l->wakeupq, skb);
920 l->stats.link_congs++;
921 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
922 return -ELINKCONG;
923}
924
925/**
926 * link_prepare_wakeup - prepare users for wakeup after congestion
927 * @l: congested link
928 * Wake up a number of waiting users, as permitted by available space
929 * in the send queue
930 */
931static void link_prepare_wakeup(struct tipc_link *l)
932{
933 struct sk_buff_head *wakeupq = &l->wakeupq;
934 struct sk_buff_head *inputq = l->inputq;
935 struct sk_buff *skb, *tmp;
936 struct sk_buff_head tmpq;
937 int avail[5] = {0,};
938 int imp = 0;
939
940 __skb_queue_head_init(&tmpq);
941
942 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
943 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
944
945 skb_queue_walk_safe(wakeupq, skb, tmp) {
946 imp = TIPC_SKB_CB(skb)->chain_imp;
947 if (avail[imp] <= 0)
948 continue;
949 avail[imp]--;
950 __skb_unlink(skb, wakeupq);
951 __skb_queue_tail(&tmpq, skb);
952 }
953
954 spin_lock_bh(&inputq->lock);
955 skb_queue_splice_tail(&tmpq, inputq);
956 spin_unlock_bh(&inputq->lock);
957
958}
959
960/**
961 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
962 * the given skb should be next attempted
963 * @skb: skb to set a future retransmission time for
964 * @l: link the skb will be transmitted on
965 */
966static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
967 struct tipc_link *l)
968{
969 if (link_is_bc_sndlink(l))
970 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
971 else
972 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
973}
974
975void tipc_link_reset(struct tipc_link *l)
976{
977 struct sk_buff_head list;
978 u32 imp;
979
980 __skb_queue_head_init(&list);
981
982 l->in_session = false;
983 /* Force re-synch of peer session number before establishing */
984 l->peer_session--;
985 l->session++;
986 l->mtu = l->advertised_mtu;
987
988 spin_lock_bh(&l->wakeupq.lock);
989 skb_queue_splice_init(&l->wakeupq, &list);
990 spin_unlock_bh(&l->wakeupq.lock);
991
992 spin_lock_bh(&l->inputq->lock);
993 skb_queue_splice_init(&list, l->inputq);
994 spin_unlock_bh(&l->inputq->lock);
995
996 __skb_queue_purge(&l->transmq);
997 __skb_queue_purge(&l->deferdq);
998 __skb_queue_purge(&l->backlogq);
999 __skb_queue_purge(&l->failover_deferdq);
1000 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
1001 l->backlog[imp].len = 0;
1002 l->backlog[imp].target_bskb = NULL;
1003 }
1004 kfree_skb(l->reasm_buf);
1005 kfree_skb(l->reasm_tnlmsg);
1006 kfree_skb(l->failover_reasm_skb);
1007 l->reasm_buf = NULL;
1008 l->reasm_tnlmsg = NULL;
1009 l->failover_reasm_skb = NULL;
1010 l->rcv_unacked = 0;
1011 l->snd_nxt = 1;
1012 l->rcv_nxt = 1;
1013 l->snd_nxt_state = 1;
1014 l->rcv_nxt_state = 1;
1015 l->acked = 0;
1016 l->last_gap = 0;
1017 kfree(l->last_ga);
1018 l->last_ga = NULL;
1019 l->silent_intv_cnt = 0;
1020 l->rst_cnt = 0;
1021 l->bc_peer_is_up = false;
1022 memset(&l->mon_state, 0, sizeof(l->mon_state));
1023 tipc_link_reset_stats(l);
1024}
1025
1026/**
1027 * tipc_link_xmit(): enqueue buffer list according to queue situation
1028 * @l: link to use
1029 * @list: chain of buffers containing message
1030 * @xmitq: returned list of packets to be sent by caller
1031 *
1032 * Consumes the buffer chain.
1033 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1034 * Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
1035 */
1036int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1037 struct sk_buff_head *xmitq)
1038{
1039 struct sk_buff_head *backlogq = &l->backlogq;
1040 struct sk_buff_head *transmq = &l->transmq;
1041 struct sk_buff *skb, *_skb;
1042 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1043 u16 ack = l->rcv_nxt - 1;
1044 u16 seqno = l->snd_nxt;
1045 int pkt_cnt = skb_queue_len(list);
1046 unsigned int mss = tipc_link_mss(l);
1047 unsigned int cwin = l->window;
1048 unsigned int mtu = l->mtu;
1049 struct tipc_msg *hdr;
1050 bool new_bundle;
1051 int rc = 0;
1052 int imp;
1053
1054 if (pkt_cnt <= 0)
1055 return 0;
1056
1057 hdr = buf_msg(skb_peek(list));
1058 if (unlikely(msg_size(hdr) > mtu)) {
1059 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1060 skb_queue_len(list), msg_user(hdr),
1061 msg_type(hdr), msg_size(hdr), mtu);
1062 __skb_queue_purge(list);
1063 return -EMSGSIZE;
1064 }
1065
1066 imp = msg_importance(hdr);
1067 /* Allow oversubscription of one data msg per source at congestion */
1068 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1069 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1070 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1071 return -ENOBUFS;
1072 }
1073 rc = link_schedule_user(l, hdr);
1074 }
1075
1076 if (pkt_cnt > 1) {
1077 l->stats.sent_fragmented++;
1078 l->stats.sent_fragments += pkt_cnt;
1079 }
1080
1081 /* Prepare each packet for sending, and add to relevant queue: */
1082 while ((skb = __skb_dequeue(list))) {
1083 if (likely(skb_queue_len(transmq) < cwin)) {
1084 hdr = buf_msg(skb);
1085 msg_set_seqno(hdr, seqno);
1086 msg_set_ack(hdr, ack);
1087 msg_set_bcast_ack(hdr, bc_ack);
1088 _skb = skb_clone(skb, GFP_ATOMIC);
1089 if (!_skb) {
1090 kfree_skb(skb);
1091 __skb_queue_purge(list);
1092 return -ENOBUFS;
1093 }
1094 __skb_queue_tail(transmq, skb);
1095 tipc_link_set_skb_retransmit_time(skb, l);
1096 __skb_queue_tail(xmitq, _skb);
1097 TIPC_SKB_CB(skb)->ackers = l->ackers;
1098 l->rcv_unacked = 0;
1099 l->stats.sent_pkts++;
1100 seqno++;
1101 continue;
1102 }
1103 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1104 mss, l->addr, &new_bundle)) {
1105 if (skb) {
1106 /* Keep a ref. to the skb for next try */
1107 l->backlog[imp].target_bskb = skb;
1108 l->backlog[imp].len++;
1109 __skb_queue_tail(backlogq, skb);
1110 } else {
1111 if (new_bundle) {
1112 l->stats.sent_bundles++;
1113 l->stats.sent_bundled++;
1114 }
1115 l->stats.sent_bundled++;
1116 }
1117 continue;
1118 }
1119 l->backlog[imp].target_bskb = NULL;
1120 l->backlog[imp].len += (1 + skb_queue_len(list));
1121 __skb_queue_tail(backlogq, skb);
1122 skb_queue_splice_tail_init(list, backlogq);
1123 }
1124 l->snd_nxt = seqno;
1125 return rc;
1126}
1127
1128static void tipc_link_update_cwin(struct tipc_link *l, int released,
1129 bool retransmitted)
1130{
1131 int bklog_len = skb_queue_len(&l->backlogq);
1132 struct sk_buff_head *txq = &l->transmq;
1133 int txq_len = skb_queue_len(txq);
1134 u16 cwin = l->window;
1135
1136 /* Enter fast recovery */
1137 if (unlikely(retransmitted)) {
1138 l->ssthresh = max_t(u16, l->window / 2, 300);
1139 l->window = min_t(u16, l->ssthresh, l->window);
1140 return;
1141 }
1142 /* Enter slow start */
1143 if (unlikely(!released)) {
1144 l->ssthresh = max_t(u16, l->window / 2, 300);
1145 l->window = l->min_win;
1146 return;
1147 }
1148 /* Don't increase window if no pressure on the transmit queue */
1149 if (txq_len + bklog_len < cwin)
1150 return;
1151
1152 /* Don't increase window if there are holes the transmit queue */
1153 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1154 return;
1155
1156 l->cong_acks += released;
1157
1158 /* Slow start */
1159 if (cwin <= l->ssthresh) {
1160 l->window = min_t(u16, cwin + released, l->max_win);
1161 return;
1162 }
1163 /* Congestion avoidance */
1164 if (l->cong_acks < cwin)
1165 return;
1166 l->window = min_t(u16, ++cwin, l->max_win);
1167 l->cong_acks = 0;
1168}
1169
1170static void tipc_link_advance_backlog(struct tipc_link *l,
1171 struct sk_buff_head *xmitq)
1172{
1173 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1174 struct sk_buff_head *txq = &l->transmq;
1175 struct sk_buff *skb, *_skb;
1176 u16 ack = l->rcv_nxt - 1;
1177 u16 seqno = l->snd_nxt;
1178 struct tipc_msg *hdr;
1179 u16 cwin = l->window;
1180 u32 imp;
1181
1182 while (skb_queue_len(txq) < cwin) {
1183 skb = skb_peek(&l->backlogq);
1184 if (!skb)
1185 break;
1186 _skb = skb_clone(skb, GFP_ATOMIC);
1187 if (!_skb)
1188 break;
1189 __skb_dequeue(&l->backlogq);
1190 hdr = buf_msg(skb);
1191 imp = msg_importance(hdr);
1192 l->backlog[imp].len--;
1193 if (unlikely(skb == l->backlog[imp].target_bskb))
1194 l->backlog[imp].target_bskb = NULL;
1195 __skb_queue_tail(&l->transmq, skb);
1196 tipc_link_set_skb_retransmit_time(skb, l);
1197
1198 __skb_queue_tail(xmitq, _skb);
1199 TIPC_SKB_CB(skb)->ackers = l->ackers;
1200 msg_set_seqno(hdr, seqno);
1201 msg_set_ack(hdr, ack);
1202 msg_set_bcast_ack(hdr, bc_ack);
1203 l->rcv_unacked = 0;
1204 l->stats.sent_pkts++;
1205 seqno++;
1206 }
1207 l->snd_nxt = seqno;
1208}
1209
1210/**
1211 * link_retransmit_failure() - Detect repeated retransmit failures
1212 * @l: tipc link sender
1213 * @r: tipc link receiver (= l in case of unicast)
1214 * @rc: returned code
1215 *
1216 * Return: true if the repeated retransmit failures happens, otherwise
1217 * false
1218 */
1219static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1220 int *rc)
1221{
1222 struct sk_buff *skb = skb_peek(&l->transmq);
1223 struct tipc_msg *hdr;
1224
1225 if (!skb)
1226 return false;
1227
1228 if (!TIPC_SKB_CB(skb)->retr_cnt)
1229 return false;
1230
1231 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1232 msecs_to_jiffies(r->tolerance * 10)))
1233 return false;
1234
1235 hdr = buf_msg(skb);
1236 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1237 return false;
1238
1239 pr_warn("Retransmission failure on link <%s>\n", l->name);
1240 link_print(l, "State of link ");
1241 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1242 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1243 pr_info("sqno %u, prev: %x, dest: %x\n",
1244 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1245 pr_info("retr_stamp %d, retr_cnt %d\n",
1246 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1247 TIPC_SKB_CB(skb)->retr_cnt);
1248
1249 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1250 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1251 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1252
1253 if (link_is_bc_sndlink(l)) {
1254 r->state = LINK_RESET;
1255 *rc |= TIPC_LINK_DOWN_EVT;
1256 } else {
1257 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1258 }
1259
1260 return true;
1261}
1262
1263/* tipc_data_input - deliver data and name distr msgs to upper layer
1264 *
1265 * Consumes buffer if message is of right type
1266 * Node lock must be held
1267 */
1268static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1269 struct sk_buff_head *inputq)
1270{
1271 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1272 struct tipc_msg *hdr = buf_msg(skb);
1273
1274 switch (msg_user(hdr)) {
1275 case TIPC_LOW_IMPORTANCE:
1276 case TIPC_MEDIUM_IMPORTANCE:
1277 case TIPC_HIGH_IMPORTANCE:
1278 case TIPC_CRITICAL_IMPORTANCE:
1279 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1280 skb_queue_tail(mc_inputq, skb);
1281 return true;
1282 }
1283 fallthrough;
1284 case CONN_MANAGER:
1285 skb_queue_tail(inputq, skb);
1286 return true;
1287 case GROUP_PROTOCOL:
1288 skb_queue_tail(mc_inputq, skb);
1289 return true;
1290 case NAME_DISTRIBUTOR:
1291 l->bc_rcvlink->state = LINK_ESTABLISHED;
1292 skb_queue_tail(l->namedq, skb);
1293 return true;
1294 case MSG_BUNDLER:
1295 case TUNNEL_PROTOCOL:
1296 case MSG_FRAGMENTER:
1297 case BCAST_PROTOCOL:
1298 return false;
1299#ifdef CONFIG_TIPC_CRYPTO
1300 case MSG_CRYPTO:
1301 tipc_crypto_msg_rcv(l->net, skb);
1302 return true;
1303#endif
1304 default:
1305 pr_warn("Dropping received illegal msg type\n");
1306 kfree_skb(skb);
1307 return true;
1308 }
1309}
1310
1311/* tipc_link_input - process packet that has passed link protocol check
1312 *
1313 * Consumes buffer
1314 */
1315static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1316 struct sk_buff_head *inputq,
1317 struct sk_buff **reasm_skb)
1318{
1319 struct tipc_msg *hdr = buf_msg(skb);
1320 struct sk_buff *iskb;
1321 struct sk_buff_head tmpq;
1322 int usr = msg_user(hdr);
1323 int pos = 0;
1324
1325 if (usr == MSG_BUNDLER) {
1326 skb_queue_head_init(&tmpq);
1327 l->stats.recv_bundles++;
1328 l->stats.recv_bundled += msg_msgcnt(hdr);
1329 while (tipc_msg_extract(skb, &iskb, &pos))
1330 tipc_data_input(l, iskb, &tmpq);
1331 tipc_skb_queue_splice_tail(&tmpq, inputq);
1332 return 0;
1333 } else if (usr == MSG_FRAGMENTER) {
1334 l->stats.recv_fragments++;
1335 if (tipc_buf_append(reasm_skb, &skb)) {
1336 l->stats.recv_fragmented++;
1337 tipc_data_input(l, skb, inputq);
1338 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1339 pr_warn_ratelimited("Unable to build fragment list\n");
1340 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1341 }
1342 return 0;
1343 } else if (usr == BCAST_PROTOCOL) {
1344 tipc_bcast_lock(l->net);
1345 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1346 tipc_bcast_unlock(l->net);
1347 }
1348
1349 kfree_skb(skb);
1350 return 0;
1351}
1352
1353/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1354 * inner message along with the ones in the old link's
1355 * deferdq
1356 * @l: tunnel link
1357 * @skb: TUNNEL_PROTOCOL message
1358 * @inputq: queue to put messages ready for delivery
1359 */
1360static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1361 struct sk_buff_head *inputq)
1362{
1363 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1364 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1365 struct sk_buff_head *fdefq = &l->failover_deferdq;
1366 struct tipc_msg *hdr = buf_msg(skb);
1367 struct sk_buff *iskb;
1368 int ipos = 0;
1369 int rc = 0;
1370 u16 seqno;
1371
1372 if (msg_type(hdr) == SYNCH_MSG) {
1373 kfree_skb(skb);
1374 return 0;
1375 }
1376
1377 /* Not a fragment? */
1378 if (likely(!msg_nof_fragms(hdr))) {
1379 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1380 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1381 skb_queue_len(fdefq));
1382 return 0;
1383 }
1384 kfree_skb(skb);
1385 } else {
1386 /* Set fragment type for buf_append */
1387 if (msg_fragm_no(hdr) == 1)
1388 msg_set_type(hdr, FIRST_FRAGMENT);
1389 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1390 msg_set_type(hdr, FRAGMENT);
1391 else
1392 msg_set_type(hdr, LAST_FRAGMENT);
1393
1394 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1395 /* Successful but non-complete reassembly? */
1396 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1397 return 0;
1398 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1399 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1400 }
1401 iskb = skb;
1402 }
1403
1404 do {
1405 seqno = buf_seqno(iskb);
1406 if (unlikely(less(seqno, l->drop_point))) {
1407 kfree_skb(iskb);
1408 continue;
1409 }
1410 if (unlikely(seqno != l->drop_point)) {
1411 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1412 continue;
1413 }
1414
1415 l->drop_point++;
1416 if (!tipc_data_input(l, iskb, inputq))
1417 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1418 if (unlikely(rc))
1419 break;
1420 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1421
1422 return rc;
1423}
1424
1425/**
1426 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1427 * @ga: returned pointer to the Gap ACK blocks if any
1428 * @l: the tipc link
1429 * @hdr: the PROTOCOL/STATE_MSG header
1430 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1431 *
1432 * Return: the total Gap ACK blocks size
1433 */
1434u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1435 struct tipc_msg *hdr, bool uc)
1436{
1437 struct tipc_gap_ack_blks *p;
1438 u16 sz = 0;
1439
1440 /* Does peer support the Gap ACK blocks feature? */
1441 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1442 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1443 sz = ntohs(p->len);
1444 /* Sanity check */
1445 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1446 /* Good, check if the desired type exists */
1447 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1448 goto ok;
1449 /* Backward compatible: peer might not support bc, but uc? */
1450 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1451 if (p->ugack_cnt) {
1452 p->bgack_cnt = 0;
1453 goto ok;
1454 }
1455 }
1456 }
1457 /* Other cases: ignore! */
1458 p = NULL;
1459
1460ok:
1461 *ga = p;
1462 return sz;
1463}
1464
1465static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1466 struct tipc_link *l, u8 start_index)
1467{
1468 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1469 struct sk_buff *skb = skb_peek(&l->deferdq);
1470 u16 expect, seqno = 0;
1471 u8 n = 0;
1472
1473 if (!skb)
1474 return 0;
1475
1476 expect = buf_seqno(skb);
1477 skb_queue_walk(&l->deferdq, skb) {
1478 seqno = buf_seqno(skb);
1479 if (unlikely(more(seqno, expect))) {
1480 gacks[n].ack = htons(expect - 1);
1481 gacks[n].gap = htons(seqno - expect);
1482 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1483 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1484 l->name, n,
1485 skb_queue_len(&l->deferdq));
1486 return n;
1487 }
1488 } else if (unlikely(less(seqno, expect))) {
1489 pr_warn("Unexpected skb in deferdq!\n");
1490 continue;
1491 }
1492 expect = seqno + 1;
1493 }
1494
1495 /* last block */
1496 gacks[n].ack = htons(seqno);
1497 gacks[n].gap = 0;
1498 n++;
1499 return n;
1500}
1501
1502/* tipc_build_gap_ack_blks - build Gap ACK blocks
1503 * @l: tipc unicast link
1504 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1505 *
1506 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1507 * links of a certain peer, the buffer after built has the network data format
1508 * as found at the struct tipc_gap_ack_blks definition.
1509 *
1510 * returns the actual allocated memory size
1511 */
1512static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1513{
1514 struct tipc_link *bcl = l->bc_rcvlink;
1515 struct tipc_gap_ack_blks *ga;
1516 u16 len;
1517
1518 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1519
1520 /* Start with broadcast link first */
1521 tipc_bcast_lock(bcl->net);
1522 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1523 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1524 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1525 tipc_bcast_unlock(bcl->net);
1526
1527 /* Now for unicast link, but an explicit NACK only (???) */
1528 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1529 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1530
1531 /* Total len */
1532 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1533 ga->len = htons(len);
1534 return len;
1535}
1536
1537/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1538 * acked packets, also doing retransmissions if
1539 * gaps found
1540 * @l: tipc link with transmq queue to be advanced
1541 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1542 * @acked: seqno of last packet acked by peer without any gaps before
1543 * @gap: # of gap packets
1544 * @ga: buffer pointer to Gap ACK blocks from peer
1545 * @xmitq: queue for accumulating the retransmitted packets if any
1546 * @retransmitted: returned boolean value if a retransmission is really issued
1547 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1548 * happens (- unlikely case)
1549 *
1550 * Return: the number of packets released from the link transmq
1551 */
1552static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1553 u16 acked, u16 gap,
1554 struct tipc_gap_ack_blks *ga,
1555 struct sk_buff_head *xmitq,
1556 bool *retransmitted, int *rc)
1557{
1558 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1559 struct tipc_gap_ack *gacks = NULL;
1560 struct sk_buff *skb, *_skb, *tmp;
1561 struct tipc_msg *hdr;
1562 u32 qlen = skb_queue_len(&l->transmq);
1563 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1564 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1565 u16 ack = l->rcv_nxt - 1;
1566 u16 seqno, n = 0;
1567 u16 end = r->acked, start = end, offset = r->last_gap;
1568 u16 si = (last_ga) ? last_ga->start_index : 0;
1569 bool is_uc = !link_is_bc_sndlink(l);
1570 bool bc_has_acked = false;
1571
1572 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1573
1574 /* Determine Gap ACK blocks if any for the particular link */
1575 if (ga && is_uc) {
1576 /* Get the Gap ACKs, uc part */
1577 gack_cnt = ga->ugack_cnt;
1578 gacks = &ga->gacks[ga->bgack_cnt];
1579 } else if (ga) {
1580 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1581 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1582 GFP_ATOMIC);
1583 if (likely(this_ga)) {
1584 this_ga->start_index = 0;
1585 /* Start with the bc Gap ACKs */
1586 gack_cnt = this_ga->bgack_cnt;
1587 gacks = &this_ga->gacks[0];
1588 } else {
1589 /* Hmm, we can get in trouble..., simply ignore it */
1590 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1591 }
1592 }
1593
1594 /* Advance the link transmq */
1595 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1596 seqno = buf_seqno(skb);
1597
1598next_gap_ack:
1599 if (less_eq(seqno, nacked)) {
1600 if (is_uc)
1601 goto release;
1602 /* Skip packets peer has already acked */
1603 if (!more(seqno, r->acked))
1604 continue;
1605 /* Get the next of last Gap ACK blocks */
1606 while (more(seqno, end)) {
1607 if (!last_ga || si >= last_ga->bgack_cnt)
1608 break;
1609 start = end + offset + 1;
1610 end = ntohs(last_ga->gacks[si].ack);
1611 offset = ntohs(last_ga->gacks[si].gap);
1612 si++;
1613 WARN_ONCE(more(start, end) ||
1614 (!offset &&
1615 si < last_ga->bgack_cnt) ||
1616 si > MAX_GAP_ACK_BLKS,
1617 "Corrupted Gap ACK: %d %d %d %d %d\n",
1618 start, end, offset, si,
1619 last_ga->bgack_cnt);
1620 }
1621 /* Check against the last Gap ACK block */
1622 if (in_range(seqno, start, end))
1623 continue;
1624 /* Update/release the packet peer is acking */
1625 bc_has_acked = true;
1626 if (--TIPC_SKB_CB(skb)->ackers)
1627 continue;
1628release:
1629 /* release skb */
1630 __skb_unlink(skb, &l->transmq);
1631 kfree_skb(skb);
1632 } else if (less_eq(seqno, nacked + ngap)) {
1633 /* First gap: check if repeated retrans failures? */
1634 if (unlikely(seqno == acked + 1 &&
1635 link_retransmit_failure(l, r, rc))) {
1636 /* Ignore this bc Gap ACKs if any */
1637 kfree(this_ga);
1638 this_ga = NULL;
1639 break;
1640 }
1641 /* retransmit skb if unrestricted*/
1642 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1643 continue;
1644 tipc_link_set_skb_retransmit_time(skb, l);
1645 _skb = pskb_copy(skb, GFP_ATOMIC);
1646 if (!_skb)
1647 continue;
1648 hdr = buf_msg(_skb);
1649 msg_set_ack(hdr, ack);
1650 msg_set_bcast_ack(hdr, bc_ack);
1651 _skb->priority = TC_PRIO_CONTROL;
1652 __skb_queue_tail(xmitq, _skb);
1653 l->stats.retransmitted++;
1654 if (!is_uc)
1655 r->stats.retransmitted++;
1656 *retransmitted = true;
1657 /* Increase actual retrans counter & mark first time */
1658 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1659 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1660 } else {
1661 /* retry with Gap ACK blocks if any */
1662 if (n >= gack_cnt)
1663 break;
1664 nacked = ntohs(gacks[n].ack);
1665 ngap = ntohs(gacks[n].gap);
1666 n++;
1667 goto next_gap_ack;
1668 }
1669 }
1670
1671 /* Renew last Gap ACK blocks for bc if needed */
1672 if (bc_has_acked) {
1673 if (this_ga) {
1674 kfree(last_ga);
1675 r->last_ga = this_ga;
1676 r->last_gap = gap;
1677 } else if (last_ga) {
1678 if (less(acked, start)) {
1679 si--;
1680 offset = start - acked - 1;
1681 } else if (less(acked, end)) {
1682 acked = end;
1683 }
1684 if (si < last_ga->bgack_cnt) {
1685 last_ga->start_index = si;
1686 r->last_gap = offset;
1687 } else {
1688 kfree(last_ga);
1689 r->last_ga = NULL;
1690 r->last_gap = 0;
1691 }
1692 } else {
1693 r->last_gap = 0;
1694 }
1695 r->acked = acked;
1696 } else {
1697 kfree(this_ga);
1698 }
1699
1700 return qlen - skb_queue_len(&l->transmq);
1701}
1702
1703/* tipc_link_build_state_msg: prepare link state message for transmission
1704 *
1705 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1706 * risk of ack storms towards the sender
1707 */
1708int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1709{
1710 if (!l)
1711 return 0;
1712
1713 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1714 if (link_is_bc_rcvlink(l)) {
1715 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1716 return 0;
1717 l->rcv_unacked = 0;
1718
1719 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1720 l->snd_nxt = l->rcv_nxt;
1721 return TIPC_LINK_SND_STATE;
1722 }
1723 /* Unicast ACK */
1724 l->rcv_unacked = 0;
1725 l->stats.sent_acks++;
1726 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1727 return 0;
1728}
1729
1730/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1731 */
1732void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1733{
1734 int mtyp = RESET_MSG;
1735 struct sk_buff *skb;
1736
1737 if (l->state == LINK_ESTABLISHING)
1738 mtyp = ACTIVATE_MSG;
1739
1740 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1741
1742 /* Inform peer that this endpoint is going down if applicable */
1743 skb = skb_peek_tail(xmitq);
1744 if (skb && (l->state == LINK_RESET))
1745 msg_set_peer_stopping(buf_msg(skb), 1);
1746}
1747
1748/* tipc_link_build_nack_msg: prepare link nack message for transmission
1749 * Note that sending of broadcast NACK is coordinated among nodes, to
1750 * reduce the risk of NACK storms towards the sender
1751 */
1752static int tipc_link_build_nack_msg(struct tipc_link *l,
1753 struct sk_buff_head *xmitq)
1754{
1755 u32 def_cnt = ++l->stats.deferred_recv;
1756 struct sk_buff_head *dfq = &l->deferdq;
1757 u32 defq_len = skb_queue_len(dfq);
1758 int match1, match2;
1759
1760 if (link_is_bc_rcvlink(l)) {
1761 match1 = def_cnt & 0xf;
1762 match2 = tipc_own_addr(l->net) & 0xf;
1763 if (match1 == match2)
1764 return TIPC_LINK_SND_STATE;
1765 return 0;
1766 }
1767
1768 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1769 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1770
1771 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1772 rcvgap, 0, 0, xmitq);
1773 }
1774 return 0;
1775}
1776
1777/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1778 * @l: the link that should handle the message
1779 * @skb: TIPC packet
1780 * @xmitq: queue to place packets to be sent after this call
1781 */
1782int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1783 struct sk_buff_head *xmitq)
1784{
1785 struct sk_buff_head *defq = &l->deferdq;
1786 struct tipc_msg *hdr = buf_msg(skb);
1787 u16 seqno, rcv_nxt, win_lim;
1788 int released = 0;
1789 int rc = 0;
1790
1791 /* Verify and update link state */
1792 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1793 return tipc_link_proto_rcv(l, skb, xmitq);
1794
1795 /* Don't send probe at next timeout expiration */
1796 l->silent_intv_cnt = 0;
1797
1798 do {
1799 hdr = buf_msg(skb);
1800 seqno = msg_seqno(hdr);
1801 rcv_nxt = l->rcv_nxt;
1802 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1803
1804 if (unlikely(!link_is_up(l))) {
1805 if (l->state == LINK_ESTABLISHING)
1806 rc = TIPC_LINK_UP_EVT;
1807 kfree_skb(skb);
1808 break;
1809 }
1810
1811 /* Drop if outside receive window */
1812 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1813 l->stats.duplicates++;
1814 kfree_skb(skb);
1815 break;
1816 }
1817 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1818 NULL, NULL, NULL, NULL);
1819
1820 /* Defer delivery if sequence gap */
1821 if (unlikely(seqno != rcv_nxt)) {
1822 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1823 l->stats.duplicates++;
1824 rc |= tipc_link_build_nack_msg(l, xmitq);
1825 break;
1826 }
1827
1828 /* Deliver packet */
1829 l->rcv_nxt++;
1830 l->stats.recv_pkts++;
1831
1832 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1833 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1834 else if (!tipc_data_input(l, skb, l->inputq))
1835 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1836 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1837 rc |= tipc_link_build_state_msg(l, xmitq);
1838 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1839 break;
1840 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1841
1842 /* Forward queues and wake up waiting users */
1843 if (released) {
1844 tipc_link_update_cwin(l, released, 0);
1845 tipc_link_advance_backlog(l, xmitq);
1846 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1847 link_prepare_wakeup(l);
1848 }
1849 return rc;
1850}
1851
1852static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1853 bool probe_reply, u16 rcvgap,
1854 int tolerance, int priority,
1855 struct sk_buff_head *xmitq)
1856{
1857 struct tipc_mon_state *mstate = &l->mon_state;
1858 struct sk_buff_head *dfq = &l->deferdq;
1859 struct tipc_link *bcl = l->bc_rcvlink;
1860 struct tipc_msg *hdr;
1861 struct sk_buff *skb;
1862 bool node_up = link_is_up(bcl);
1863 u16 glen = 0, bc_rcvgap = 0;
1864 int dlen = 0;
1865 void *data;
1866
1867 /* Don't send protocol message during reset or link failover */
1868 if (tipc_link_is_blocked(l))
1869 return;
1870
1871 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1872 return;
1873
1874 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1875 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1876
1877 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1878 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1879 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1880 if (!skb)
1881 return;
1882
1883 hdr = buf_msg(skb);
1884 data = msg_data(hdr);
1885 msg_set_session(hdr, l->session);
1886 msg_set_bearer_id(hdr, l->bearer_id);
1887 msg_set_net_plane(hdr, l->net_plane);
1888 msg_set_next_sent(hdr, l->snd_nxt);
1889 msg_set_ack(hdr, l->rcv_nxt - 1);
1890 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1891 msg_set_bc_ack_invalid(hdr, !node_up);
1892 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1893 msg_set_link_tolerance(hdr, tolerance);
1894 msg_set_linkprio(hdr, priority);
1895 msg_set_redundant_link(hdr, node_up);
1896 msg_set_seq_gap(hdr, 0);
1897 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1898
1899 if (mtyp == STATE_MSG) {
1900 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1901 msg_set_seqno(hdr, l->snd_nxt_state++);
1902 msg_set_seq_gap(hdr, rcvgap);
1903 bc_rcvgap = link_bc_rcv_gap(bcl);
1904 msg_set_bc_gap(hdr, bc_rcvgap);
1905 msg_set_probe(hdr, probe);
1906 msg_set_is_keepalive(hdr, probe || probe_reply);
1907 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1908 glen = tipc_build_gap_ack_blks(l, hdr);
1909 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1910 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1911 skb_trim(skb, INT_H_SIZE + glen + dlen);
1912 l->stats.sent_states++;
1913 l->rcv_unacked = 0;
1914 } else {
1915 /* RESET_MSG or ACTIVATE_MSG */
1916 if (mtyp == ACTIVATE_MSG) {
1917 msg_set_dest_session_valid(hdr, 1);
1918 msg_set_dest_session(hdr, l->peer_session);
1919 }
1920 msg_set_max_pkt(hdr, l->advertised_mtu);
1921 strcpy(data, l->if_name);
1922 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1923 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1924 }
1925 if (probe)
1926 l->stats.sent_probes++;
1927 if (rcvgap)
1928 l->stats.sent_nacks++;
1929 if (bc_rcvgap)
1930 bcl->stats.sent_nacks++;
1931 skb->priority = TC_PRIO_CONTROL;
1932 __skb_queue_tail(xmitq, skb);
1933 trace_tipc_proto_build(skb, false, l->name);
1934}
1935
1936void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1937 struct sk_buff_head *xmitq)
1938{
1939 u32 onode = tipc_own_addr(l->net);
1940 struct tipc_msg *hdr, *ihdr;
1941 struct sk_buff_head tnlq;
1942 struct sk_buff *skb;
1943 u32 dnode = l->addr;
1944
1945 __skb_queue_head_init(&tnlq);
1946 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1947 INT_H_SIZE, BASIC_H_SIZE,
1948 dnode, onode, 0, 0, 0);
1949 if (!skb) {
1950 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1951 return;
1952 }
1953
1954 hdr = buf_msg(skb);
1955 msg_set_msgcnt(hdr, 1);
1956 msg_set_bearer_id(hdr, l->peer_bearer_id);
1957
1958 ihdr = (struct tipc_msg *)msg_data(hdr);
1959 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1960 BASIC_H_SIZE, dnode);
1961 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1962 __skb_queue_tail(&tnlq, skb);
1963 tipc_link_xmit(l, &tnlq, xmitq);
1964}
1965
1966/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1967 * with contents of the link's transmit and backlog queues.
1968 */
1969void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1970 int mtyp, struct sk_buff_head *xmitq)
1971{
1972 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1973 struct sk_buff *skb, *tnlskb;
1974 struct tipc_msg *hdr, tnlhdr;
1975 struct sk_buff_head *queue = &l->transmq;
1976 struct sk_buff_head tmpxq, tnlq, frags;
1977 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1978 bool pktcnt_need_update = false;
1979 u16 syncpt;
1980 int rc;
1981
1982 if (!tnl)
1983 return;
1984
1985 __skb_queue_head_init(&tnlq);
1986 /* Link Synching:
1987 * From now on, send only one single ("dummy") SYNCH message
1988 * to peer. The SYNCH message does not contain any data, just
1989 * a header conveying the synch point to the peer.
1990 */
1991 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1992 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1993 INT_H_SIZE, 0, l->addr,
1994 tipc_own_addr(l->net),
1995 0, 0, 0);
1996 if (!tnlskb) {
1997 pr_warn("%sunable to create dummy SYNCH_MSG\n",
1998 link_co_err);
1999 return;
2000 }
2001
2002 hdr = buf_msg(tnlskb);
2003 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
2004 msg_set_syncpt(hdr, syncpt);
2005 msg_set_bearer_id(hdr, l->peer_bearer_id);
2006 __skb_queue_tail(&tnlq, tnlskb);
2007 tipc_link_xmit(tnl, &tnlq, xmitq);
2008 return;
2009 }
2010
2011 __skb_queue_head_init(&tmpxq);
2012 __skb_queue_head_init(&frags);
2013 /* At least one packet required for safe algorithm => add dummy */
2014 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
2015 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
2016 0, 0, TIPC_ERR_NO_PORT);
2017 if (!skb) {
2018 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2019 return;
2020 }
2021 __skb_queue_tail(&tnlq, skb);
2022 tipc_link_xmit(l, &tnlq, &tmpxq);
2023 __skb_queue_purge(&tmpxq);
2024
2025 /* Initialize reusable tunnel packet header */
2026 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2027 mtyp, INT_H_SIZE, l->addr);
2028 if (mtyp == SYNCH_MSG)
2029 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2030 else
2031 pktcnt = skb_queue_len(&l->transmq);
2032 pktcnt += skb_queue_len(&l->backlogq);
2033 msg_set_msgcnt(&tnlhdr, pktcnt);
2034 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2035tnl:
2036 /* Wrap each packet into a tunnel packet */
2037 skb_queue_walk(queue, skb) {
2038 hdr = buf_msg(skb);
2039 if (queue == &l->backlogq)
2040 msg_set_seqno(hdr, seqno++);
2041 pktlen = msg_size(hdr);
2042
2043 /* Tunnel link MTU is not large enough? This could be
2044 * due to:
2045 * 1) Link MTU has just changed or set differently;
2046 * 2) Or FAILOVER on the top of a SYNCH message
2047 *
2048 * The 2nd case should not happen if peer supports
2049 * TIPC_TUNNEL_ENHANCED
2050 */
2051 if (pktlen > tnl->mtu - INT_H_SIZE) {
2052 if (mtyp == FAILOVER_MSG &&
2053 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2054 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2055 &frags);
2056 if (rc) {
2057 pr_warn("%sunable to frag msg: rc %d\n",
2058 link_co_err, rc);
2059 return;
2060 }
2061 pktcnt += skb_queue_len(&frags) - 1;
2062 pktcnt_need_update = true;
2063 skb_queue_splice_tail_init(&frags, &tnlq);
2064 continue;
2065 }
2066 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2067 * => Just warn it and return!
2068 */
2069 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2070 link_co_err, msg_user(hdr),
2071 msg_type(hdr), msg_size(hdr));
2072 return;
2073 }
2074
2075 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2076 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2077 if (!tnlskb) {
2078 pr_warn("%sunable to send packet\n", link_co_err);
2079 return;
2080 }
2081 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2082 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2083 __skb_queue_tail(&tnlq, tnlskb);
2084 }
2085 if (queue != &l->backlogq) {
2086 queue = &l->backlogq;
2087 goto tnl;
2088 }
2089
2090 if (pktcnt_need_update)
2091 skb_queue_walk(&tnlq, skb) {
2092 hdr = buf_msg(skb);
2093 msg_set_msgcnt(hdr, pktcnt);
2094 }
2095
2096 tipc_link_xmit(tnl, &tnlq, xmitq);
2097
2098 if (mtyp == FAILOVER_MSG) {
2099 tnl->drop_point = l->rcv_nxt;
2100 tnl->failover_reasm_skb = l->reasm_buf;
2101 l->reasm_buf = NULL;
2102
2103 /* Failover the link's deferdq */
2104 if (unlikely(!skb_queue_empty(fdefq))) {
2105 pr_warn("Link failover deferdq not empty: %d!\n",
2106 skb_queue_len(fdefq));
2107 __skb_queue_purge(fdefq);
2108 }
2109 skb_queue_splice_init(&l->deferdq, fdefq);
2110 }
2111}
2112
2113/**
2114 * tipc_link_failover_prepare() - prepare tnl for link failover
2115 *
2116 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2117 * see the tipc_node_link_failover() for details
2118 *
2119 * @l: failover link
2120 * @tnl: tunnel link
2121 * @xmitq: queue for messages to be xmited
2122 */
2123void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2124 struct sk_buff_head *xmitq)
2125{
2126 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2127
2128 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2129
2130 /* This failover link endpoint was never established before,
2131 * so it has not received anything from peer.
2132 * Otherwise, it must be a normal failover situation or the
2133 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2134 * would have to start over from scratch instead.
2135 */
2136 tnl->drop_point = 1;
2137 tnl->failover_reasm_skb = NULL;
2138
2139 /* Initiate the link's failover deferdq */
2140 if (unlikely(!skb_queue_empty(fdefq))) {
2141 pr_warn("Link failover deferdq not empty: %d!\n",
2142 skb_queue_len(fdefq));
2143 __skb_queue_purge(fdefq);
2144 }
2145}
2146
2147/* tipc_link_validate_msg(): validate message against current link state
2148 * Returns true if message should be accepted, otherwise false
2149 */
2150bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2151{
2152 u16 curr_session = l->peer_session;
2153 u16 session = msg_session(hdr);
2154 int mtyp = msg_type(hdr);
2155
2156 if (msg_user(hdr) != LINK_PROTOCOL)
2157 return true;
2158
2159 switch (mtyp) {
2160 case RESET_MSG:
2161 if (!l->in_session)
2162 return true;
2163 /* Accept only RESET with new session number */
2164 return more(session, curr_session);
2165 case ACTIVATE_MSG:
2166 if (!l->in_session)
2167 return true;
2168 /* Accept only ACTIVATE with new or current session number */
2169 return !less(session, curr_session);
2170 case STATE_MSG:
2171 /* Accept only STATE with current session number */
2172 if (!l->in_session)
2173 return false;
2174 if (session != curr_session)
2175 return false;
2176 /* Extra sanity check */
2177 if (!link_is_up(l) && msg_ack(hdr))
2178 return false;
2179 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2180 return true;
2181 /* Accept only STATE with new sequence number */
2182 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2183 default:
2184 return false;
2185 }
2186}
2187
2188/* tipc_link_proto_rcv(): receive link level protocol message :
2189 * Note that network plane id propagates through the network, and may
2190 * change at any time. The node with lowest numerical id determines
2191 * network plane
2192 */
2193static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2194 struct sk_buff_head *xmitq)
2195{
2196 struct tipc_msg *hdr = buf_msg(skb);
2197 struct tipc_gap_ack_blks *ga = NULL;
2198 bool reply = msg_probe(hdr), retransmitted = false;
2199 u16 dlen = msg_data_sz(hdr), glen = 0;
2200 u16 peers_snd_nxt = msg_next_sent(hdr);
2201 u16 peers_tol = msg_link_tolerance(hdr);
2202 u16 peers_prio = msg_linkprio(hdr);
2203 u16 gap = msg_seq_gap(hdr);
2204 u16 ack = msg_ack(hdr);
2205 u16 rcv_nxt = l->rcv_nxt;
2206 u16 rcvgap = 0;
2207 int mtyp = msg_type(hdr);
2208 int rc = 0, released;
2209 char *if_name;
2210 void *data;
2211
2212 trace_tipc_proto_rcv(skb, false, l->name);
2213 if (tipc_link_is_blocked(l) || !xmitq)
2214 goto exit;
2215
2216 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2217 l->net_plane = msg_net_plane(hdr);
2218
2219 skb_linearize(skb);
2220 hdr = buf_msg(skb);
2221 data = msg_data(hdr);
2222
2223 if (!tipc_link_validate_msg(l, hdr)) {
2224 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2225 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2226 goto exit;
2227 }
2228
2229 switch (mtyp) {
2230 case RESET_MSG:
2231 case ACTIVATE_MSG:
2232 /* Complete own link name with peer's interface name */
2233 if_name = strrchr(l->name, ':') + 1;
2234 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2235 break;
2236 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2237 break;
2238 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2239
2240 /* Update own tolerance if peer indicates a non-zero value */
2241 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2242 l->tolerance = peers_tol;
2243 l->bc_rcvlink->tolerance = peers_tol;
2244 }
2245 /* Update own priority if peer's priority is higher */
2246 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2247 l->priority = peers_prio;
2248
2249 /* If peer is going down we want full re-establish cycle */
2250 if (msg_peer_stopping(hdr)) {
2251 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2252 break;
2253 }
2254
2255 /* If this endpoint was re-created while peer was ESTABLISHING
2256 * it doesn't know current session number. Force re-synch.
2257 */
2258 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2259 l->session != msg_dest_session(hdr)) {
2260 if (less(l->session, msg_dest_session(hdr)))
2261 l->session = msg_dest_session(hdr) + 1;
2262 break;
2263 }
2264
2265 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2266 if (mtyp == RESET_MSG || !link_is_up(l))
2267 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2268
2269 /* ACTIVATE_MSG takes up link if it was already locally reset */
2270 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2271 rc = TIPC_LINK_UP_EVT;
2272
2273 l->peer_session = msg_session(hdr);
2274 l->in_session = true;
2275 l->peer_bearer_id = msg_bearer_id(hdr);
2276 if (l->mtu > msg_max_pkt(hdr))
2277 l->mtu = msg_max_pkt(hdr);
2278 break;
2279
2280 case STATE_MSG:
2281 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2282
2283 /* Update own tolerance if peer indicates a non-zero value */
2284 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2285 l->tolerance = peers_tol;
2286 l->bc_rcvlink->tolerance = peers_tol;
2287 }
2288 /* Update own prio if peer indicates a different value */
2289 if ((peers_prio != l->priority) &&
2290 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2291 l->priority = peers_prio;
2292 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2293 }
2294
2295 l->silent_intv_cnt = 0;
2296 l->stats.recv_states++;
2297 if (msg_probe(hdr))
2298 l->stats.recv_probes++;
2299
2300 if (!link_is_up(l)) {
2301 if (l->state == LINK_ESTABLISHING)
2302 rc = TIPC_LINK_UP_EVT;
2303 break;
2304 }
2305
2306 /* Receive Gap ACK blocks from peer if any */
2307 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2308
2309 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2310 &l->mon_state, l->bearer_id);
2311
2312 /* Send NACK if peer has sent pkts we haven't received yet */
2313 if ((reply || msg_is_keepalive(hdr)) &&
2314 more(peers_snd_nxt, rcv_nxt) &&
2315 !tipc_link_is_synching(l) &&
2316 skb_queue_empty(&l->deferdq))
2317 rcvgap = peers_snd_nxt - l->rcv_nxt;
2318 if (rcvgap || reply)
2319 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2320 rcvgap, 0, 0, xmitq);
2321
2322 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2323 &retransmitted, &rc);
2324 if (gap)
2325 l->stats.recv_nacks++;
2326 if (released || retransmitted)
2327 tipc_link_update_cwin(l, released, retransmitted);
2328 if (released)
2329 tipc_link_advance_backlog(l, xmitq);
2330 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2331 link_prepare_wakeup(l);
2332 }
2333exit:
2334 kfree_skb(skb);
2335 return rc;
2336}
2337
2338/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2339 */
2340static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2341 u16 peers_snd_nxt,
2342 struct sk_buff_head *xmitq)
2343{
2344 struct sk_buff *skb;
2345 struct tipc_msg *hdr;
2346 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2347 u16 ack = l->rcv_nxt - 1;
2348 u16 gap_to = peers_snd_nxt - 1;
2349
2350 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2351 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2352 if (!skb)
2353 return false;
2354 hdr = buf_msg(skb);
2355 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2356 msg_set_bcast_ack(hdr, ack);
2357 msg_set_bcgap_after(hdr, ack);
2358 if (dfrd_skb)
2359 gap_to = buf_seqno(dfrd_skb) - 1;
2360 msg_set_bcgap_to(hdr, gap_to);
2361 msg_set_non_seq(hdr, bcast);
2362 __skb_queue_tail(xmitq, skb);
2363 return true;
2364}
2365
2366/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2367 *
2368 * Give a newly added peer node the sequence number where it should
2369 * start receiving and acking broadcast packets.
2370 */
2371static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2372 struct sk_buff_head *xmitq)
2373{
2374 struct sk_buff_head list;
2375
2376 __skb_queue_head_init(&list);
2377 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2378 return;
2379 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2380 tipc_link_xmit(l, &list, xmitq);
2381}
2382
2383/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2384 */
2385void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2386{
2387 int mtyp = msg_type(hdr);
2388 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2389
2390 if (link_is_up(l))
2391 return;
2392
2393 if (msg_user(hdr) == BCAST_PROTOCOL) {
2394 l->rcv_nxt = peers_snd_nxt;
2395 l->state = LINK_ESTABLISHED;
2396 return;
2397 }
2398
2399 if (l->peer_caps & TIPC_BCAST_SYNCH)
2400 return;
2401
2402 if (msg_peer_node_is_up(hdr))
2403 return;
2404
2405 /* Compatibility: accept older, less safe initial synch data */
2406 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2407 l->rcv_nxt = peers_snd_nxt;
2408}
2409
2410/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2411 */
2412int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2413 struct sk_buff_head *xmitq)
2414{
2415 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2416 int rc = 0;
2417
2418 if (!link_is_up(l))
2419 return rc;
2420
2421 if (!msg_peer_node_is_up(hdr))
2422 return rc;
2423
2424 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2425 if (msg_ack(hdr))
2426 l->bc_peer_is_up = true;
2427
2428 if (!l->bc_peer_is_up)
2429 return rc;
2430
2431 /* Ignore if peers_snd_nxt goes beyond receive window */
2432 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2433 return rc;
2434
2435 l->snd_nxt = peers_snd_nxt;
2436 if (link_bc_rcv_gap(l))
2437 rc |= TIPC_LINK_SND_STATE;
2438
2439 /* Return now if sender supports nack via STATE messages */
2440 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2441 return rc;
2442
2443 /* Otherwise, be backwards compatible */
2444
2445 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2446 l->nack_state = BC_NACK_SND_CONDITIONAL;
2447 return 0;
2448 }
2449
2450 /* Don't NACK if one was recently sent or peeked */
2451 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2452 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2453 return 0;
2454 }
2455
2456 /* Conditionally delay NACK sending until next synch rcv */
2457 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2458 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2459 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2460 return 0;
2461 }
2462
2463 /* Send NACK now but suppress next one */
2464 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2465 l->nack_state = BC_NACK_SND_SUPPRESS;
2466 return 0;
2467}
2468
2469int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2470 struct tipc_gap_ack_blks *ga,
2471 struct sk_buff_head *xmitq,
2472 struct sk_buff_head *retrq)
2473{
2474 struct tipc_link *l = r->bc_sndlink;
2475 bool unused = false;
2476 int rc = 0;
2477
2478 if (!link_is_up(r) || !r->bc_peer_is_up)
2479 return 0;
2480
2481 if (gap) {
2482 l->stats.recv_nacks++;
2483 r->stats.recv_nacks++;
2484 }
2485
2486 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2487 return 0;
2488
2489 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2490 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2491
2492 tipc_link_advance_backlog(l, xmitq);
2493 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2494 link_prepare_wakeup(l);
2495
2496 return rc;
2497}
2498
2499/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2500 * This function is here for backwards compatibility, since
2501 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2502 */
2503int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2504 struct sk_buff_head *xmitq)
2505{
2506 struct tipc_msg *hdr = buf_msg(skb);
2507 u32 dnode = msg_destnode(hdr);
2508 int mtyp = msg_type(hdr);
2509 u16 acked = msg_bcast_ack(hdr);
2510 u16 from = acked + 1;
2511 u16 to = msg_bcgap_to(hdr);
2512 u16 peers_snd_nxt = to + 1;
2513 int rc = 0;
2514
2515 kfree_skb(skb);
2516
2517 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2518 return 0;
2519
2520 if (mtyp != STATE_MSG)
2521 return 0;
2522
2523 if (dnode == tipc_own_addr(l->net)) {
2524 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2525 xmitq);
2526 l->stats.recv_nacks++;
2527 return rc;
2528 }
2529
2530 /* Msg for other node => suppress own NACK at next sync if applicable */
2531 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2532 l->nack_state = BC_NACK_SND_SUPPRESS;
2533
2534 return 0;
2535}
2536
2537void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2538{
2539 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2540
2541 l->min_win = min_win;
2542 l->ssthresh = max_win;
2543 l->max_win = max_win;
2544 l->window = min_win;
2545 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2546 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2547 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2548 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2549 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2550}
2551
2552/**
2553 * tipc_link_reset_stats - reset link statistics
2554 * @l: pointer to link
2555 */
2556void tipc_link_reset_stats(struct tipc_link *l)
2557{
2558 memset(&l->stats, 0, sizeof(l->stats));
2559}
2560
2561static void link_print(struct tipc_link *l, const char *str)
2562{
2563 struct sk_buff *hskb = skb_peek(&l->transmq);
2564 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2565 u16 tail = l->snd_nxt - 1;
2566
2567 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2568 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2569 skb_queue_len(&l->transmq), head, tail,
2570 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2571}
2572
2573/* Parse and validate nested (link) properties valid for media, bearer and link
2574 */
2575int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2576{
2577 int err;
2578
2579 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2580 tipc_nl_prop_policy, NULL);
2581 if (err)
2582 return err;
2583
2584 if (props[TIPC_NLA_PROP_PRIO]) {
2585 u32 prio;
2586
2587 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2588 if (prio > TIPC_MAX_LINK_PRI)
2589 return -EINVAL;
2590 }
2591
2592 if (props[TIPC_NLA_PROP_TOL]) {
2593 u32 tol;
2594
2595 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2596 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2597 return -EINVAL;
2598 }
2599
2600 if (props[TIPC_NLA_PROP_WIN]) {
2601 u32 max_win;
2602
2603 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2604 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2605 return -EINVAL;
2606 }
2607
2608 return 0;
2609}
2610
2611static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2612{
2613 int i;
2614 struct nlattr *stats;
2615
2616 struct nla_map {
2617 u32 key;
2618 u32 val;
2619 };
2620
2621 struct nla_map map[] = {
2622 {TIPC_NLA_STATS_RX_INFO, 0},
2623 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2624 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2625 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2626 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2627 {TIPC_NLA_STATS_TX_INFO, 0},
2628 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2629 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2630 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2631 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2632 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2633 s->msg_length_counts : 1},
2634 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2635 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2636 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2637 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2638 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2639 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2640 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2641 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2642 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2643 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2644 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2645 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2646 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2647 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2648 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2649 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2650 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2651 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2652 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2653 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2654 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2655 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2656 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2657 };
2658
2659 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2660 if (!stats)
2661 return -EMSGSIZE;
2662
2663 for (i = 0; i < ARRAY_SIZE(map); i++)
2664 if (nla_put_u32(skb, map[i].key, map[i].val))
2665 goto msg_full;
2666
2667 nla_nest_end(skb, stats);
2668
2669 return 0;
2670msg_full:
2671 nla_nest_cancel(skb, stats);
2672
2673 return -EMSGSIZE;
2674}
2675
2676/* Caller should hold appropriate locks to protect the link */
2677int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2678 struct tipc_link *link, int nlflags)
2679{
2680 u32 self = tipc_own_addr(net);
2681 struct nlattr *attrs;
2682 struct nlattr *prop;
2683 void *hdr;
2684 int err;
2685
2686 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2687 nlflags, TIPC_NL_LINK_GET);
2688 if (!hdr)
2689 return -EMSGSIZE;
2690
2691 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2692 if (!attrs)
2693 goto msg_full;
2694
2695 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2696 goto attr_msg_full;
2697 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2698 goto attr_msg_full;
2699 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2700 goto attr_msg_full;
2701 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2702 goto attr_msg_full;
2703 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2704 goto attr_msg_full;
2705
2706 if (tipc_link_is_up(link))
2707 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2708 goto attr_msg_full;
2709 if (link->active)
2710 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2711 goto attr_msg_full;
2712
2713 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2714 if (!prop)
2715 goto attr_msg_full;
2716 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2717 goto prop_msg_full;
2718 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2719 goto prop_msg_full;
2720 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2721 link->window))
2722 goto prop_msg_full;
2723 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2724 goto prop_msg_full;
2725 nla_nest_end(msg->skb, prop);
2726
2727 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2728 if (err)
2729 goto attr_msg_full;
2730
2731 nla_nest_end(msg->skb, attrs);
2732 genlmsg_end(msg->skb, hdr);
2733
2734 return 0;
2735
2736prop_msg_full:
2737 nla_nest_cancel(msg->skb, prop);
2738attr_msg_full:
2739 nla_nest_cancel(msg->skb, attrs);
2740msg_full:
2741 genlmsg_cancel(msg->skb, hdr);
2742
2743 return -EMSGSIZE;
2744}
2745
2746static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2747 struct tipc_stats *stats)
2748{
2749 int i;
2750 struct nlattr *nest;
2751
2752 struct nla_map {
2753 __u32 key;
2754 __u32 val;
2755 };
2756
2757 struct nla_map map[] = {
2758 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2759 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2760 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2761 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2762 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2763 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2764 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2765 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2766 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2767 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2768 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2769 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2770 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2771 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2772 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2773 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2774 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2775 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2776 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2777 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2778 };
2779
2780 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2781 if (!nest)
2782 return -EMSGSIZE;
2783
2784 for (i = 0; i < ARRAY_SIZE(map); i++)
2785 if (nla_put_u32(skb, map[i].key, map[i].val))
2786 goto msg_full;
2787
2788 nla_nest_end(skb, nest);
2789
2790 return 0;
2791msg_full:
2792 nla_nest_cancel(skb, nest);
2793
2794 return -EMSGSIZE;
2795}
2796
2797int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2798 struct tipc_link *bcl)
2799{
2800 int err;
2801 void *hdr;
2802 struct nlattr *attrs;
2803 struct nlattr *prop;
2804 u32 bc_mode = tipc_bcast_get_mode(net);
2805 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2806
2807 if (!bcl)
2808 return 0;
2809
2810 tipc_bcast_lock(net);
2811
2812 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2813 NLM_F_MULTI, TIPC_NL_LINK_GET);
2814 if (!hdr) {
2815 tipc_bcast_unlock(net);
2816 return -EMSGSIZE;
2817 }
2818
2819 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2820 if (!attrs)
2821 goto msg_full;
2822
2823 /* The broadcast link is always up */
2824 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2825 goto attr_msg_full;
2826
2827 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2828 goto attr_msg_full;
2829 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2830 goto attr_msg_full;
2831 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2832 goto attr_msg_full;
2833 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2834 goto attr_msg_full;
2835
2836 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2837 if (!prop)
2838 goto attr_msg_full;
2839 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2840 goto prop_msg_full;
2841 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2842 goto prop_msg_full;
2843 if (bc_mode & BCLINK_MODE_SEL)
2844 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2845 bc_ratio))
2846 goto prop_msg_full;
2847 nla_nest_end(msg->skb, prop);
2848
2849 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2850 if (err)
2851 goto attr_msg_full;
2852
2853 tipc_bcast_unlock(net);
2854 nla_nest_end(msg->skb, attrs);
2855 genlmsg_end(msg->skb, hdr);
2856
2857 return 0;
2858
2859prop_msg_full:
2860 nla_nest_cancel(msg->skb, prop);
2861attr_msg_full:
2862 nla_nest_cancel(msg->skb, attrs);
2863msg_full:
2864 tipc_bcast_unlock(net);
2865 genlmsg_cancel(msg->skb, hdr);
2866
2867 return -EMSGSIZE;
2868}
2869
2870void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2871 struct sk_buff_head *xmitq)
2872{
2873 l->tolerance = tol;
2874 if (l->bc_rcvlink)
2875 l->bc_rcvlink->tolerance = tol;
2876 if (link_is_up(l))
2877 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2878}
2879
2880void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2881 struct sk_buff_head *xmitq)
2882{
2883 l->priority = prio;
2884 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2885}
2886
2887void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2888{
2889 l->abort_limit = limit;
2890}
2891
2892/**
2893 * tipc_link_dump - dump TIPC link data
2894 * @l: tipc link to be dumped
2895 * @dqueues: bitmask to decide if any link queue to be dumped?
2896 * - TIPC_DUMP_NONE: don't dump link queues
2897 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2898 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2899 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2900 * - TIPC_DUMP_INPUTQ: dump link input queue
2901 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2902 * - TIPC_DUMP_ALL: dump all the link queues above
2903 * @buf: returned buffer of dump data in format
2904 */
2905int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2906{
2907 int i = 0;
2908 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2909 struct sk_buff_head *list;
2910 struct sk_buff *hskb, *tskb;
2911 u32 len;
2912
2913 if (!l) {
2914 i += scnprintf(buf, sz, "link data: (null)\n");
2915 return i;
2916 }
2917
2918 i += scnprintf(buf, sz, "link data: %x", l->addr);
2919 i += scnprintf(buf + i, sz - i, " %x", l->state);
2920 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2921 i += scnprintf(buf + i, sz - i, " %u", l->session);
2922 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2923 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2924 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2925 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2926 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2927 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2928 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2929 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2930 i += scnprintf(buf + i, sz - i, " %u", 0);
2931 i += scnprintf(buf + i, sz - i, " %u", 0);
2932 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2933
2934 list = &l->transmq;
2935 len = skb_queue_len(list);
2936 hskb = skb_peek(list);
2937 tskb = skb_peek_tail(list);
2938 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2939 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2940 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2941
2942 list = &l->deferdq;
2943 len = skb_queue_len(list);
2944 hskb = skb_peek(list);
2945 tskb = skb_peek_tail(list);
2946 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2947 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2948 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2949
2950 list = &l->backlogq;
2951 len = skb_queue_len(list);
2952 hskb = skb_peek(list);
2953 tskb = skb_peek_tail(list);
2954 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2955 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2956 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2957
2958 list = l->inputq;
2959 len = skb_queue_len(list);
2960 hskb = skb_peek(list);
2961 tskb = skb_peek_tail(list);
2962 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2963 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2964 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2965
2966 if (dqueues & TIPC_DUMP_TRANSMQ) {
2967 i += scnprintf(buf + i, sz - i, "transmq: ");
2968 i += tipc_list_dump(&l->transmq, false, buf + i);
2969 }
2970 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2971 i += scnprintf(buf + i, sz - i,
2972 "backlogq: <%u %u %u %u %u>, ",
2973 l->backlog[TIPC_LOW_IMPORTANCE].len,
2974 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2975 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2976 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2977 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2978 i += tipc_list_dump(&l->backlogq, false, buf + i);
2979 }
2980 if (dqueues & TIPC_DUMP_DEFERDQ) {
2981 i += scnprintf(buf + i, sz - i, "deferdq: ");
2982 i += tipc_list_dump(&l->deferdq, false, buf + i);
2983 }
2984 if (dqueues & TIPC_DUMP_INPUTQ) {
2985 i += scnprintf(buf + i, sz - i, "inputq: ");
2986 i += tipc_list_dump(l->inputq, false, buf + i);
2987 }
2988 if (dqueues & TIPC_DUMP_WAKEUP) {
2989 i += scnprintf(buf + i, sz - i, "wakeup: ");
2990 i += tipc_list_dump(&l->wakeupq, false, buf + i);
2991 }
2992
2993 return i;
2994}
1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "subscr.h"
39#include "link.h"
40#include "bcast.h"
41#include "socket.h"
42#include "name_distr.h"
43#include "discover.h"
44#include "netlink.h"
45#include "monitor.h"
46
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}