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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 if (sysctl_tipc_key_exchange_enabled &&
1302 TIPC_SKB_CB(skb)->decrypted) {
1303 tipc_crypto_msg_rcv(l->net, skb);
1304 return true;
1305 }
1306 fallthrough;
1307#endif
1308 default:
1309 pr_warn("Dropping received illegal msg type\n");
1310 kfree_skb(skb);
1311 return true;
1312 }
1313}
1314
1315/* tipc_link_input - process packet that has passed link protocol check
1316 *
1317 * Consumes buffer
1318 */
1319static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1320 struct sk_buff_head *inputq,
1321 struct sk_buff **reasm_skb)
1322{
1323 struct tipc_msg *hdr = buf_msg(skb);
1324 struct sk_buff *iskb;
1325 struct sk_buff_head tmpq;
1326 int usr = msg_user(hdr);
1327 int pos = 0;
1328
1329 if (usr == MSG_BUNDLER) {
1330 skb_queue_head_init(&tmpq);
1331 l->stats.recv_bundles++;
1332 l->stats.recv_bundled += msg_msgcnt(hdr);
1333 while (tipc_msg_extract(skb, &iskb, &pos))
1334 tipc_data_input(l, iskb, &tmpq);
1335 tipc_skb_queue_splice_tail(&tmpq, inputq);
1336 return 0;
1337 } else if (usr == MSG_FRAGMENTER) {
1338 l->stats.recv_fragments++;
1339 if (tipc_buf_append(reasm_skb, &skb)) {
1340 l->stats.recv_fragmented++;
1341 tipc_data_input(l, skb, inputq);
1342 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1343 pr_warn_ratelimited("Unable to build fragment list\n");
1344 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1345 }
1346 return 0;
1347 } else if (usr == BCAST_PROTOCOL) {
1348 tipc_bcast_lock(l->net);
1349 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1350 tipc_bcast_unlock(l->net);
1351 }
1352
1353 kfree_skb(skb);
1354 return 0;
1355}
1356
1357/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1358 * inner message along with the ones in the old link's
1359 * deferdq
1360 * @l: tunnel link
1361 * @skb: TUNNEL_PROTOCOL message
1362 * @inputq: queue to put messages ready for delivery
1363 */
1364static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1365 struct sk_buff_head *inputq)
1366{
1367 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1368 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1369 struct sk_buff_head *fdefq = &l->failover_deferdq;
1370 struct tipc_msg *hdr = buf_msg(skb);
1371 struct sk_buff *iskb;
1372 int ipos = 0;
1373 int rc = 0;
1374 u16 seqno;
1375
1376 if (msg_type(hdr) == SYNCH_MSG) {
1377 kfree_skb(skb);
1378 return 0;
1379 }
1380
1381 /* Not a fragment? */
1382 if (likely(!msg_nof_fragms(hdr))) {
1383 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1384 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1385 skb_queue_len(fdefq));
1386 return 0;
1387 }
1388 kfree_skb(skb);
1389 } else {
1390 /* Set fragment type for buf_append */
1391 if (msg_fragm_no(hdr) == 1)
1392 msg_set_type(hdr, FIRST_FRAGMENT);
1393 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1394 msg_set_type(hdr, FRAGMENT);
1395 else
1396 msg_set_type(hdr, LAST_FRAGMENT);
1397
1398 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1399 /* Successful but non-complete reassembly? */
1400 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1401 return 0;
1402 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1403 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1404 }
1405 iskb = skb;
1406 }
1407
1408 do {
1409 seqno = buf_seqno(iskb);
1410 if (unlikely(less(seqno, l->drop_point))) {
1411 kfree_skb(iskb);
1412 continue;
1413 }
1414 if (unlikely(seqno != l->drop_point)) {
1415 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1416 continue;
1417 }
1418
1419 l->drop_point++;
1420 if (!tipc_data_input(l, iskb, inputq))
1421 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1422 if (unlikely(rc))
1423 break;
1424 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1425
1426 return rc;
1427}
1428
1429/**
1430 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1431 * @ga: returned pointer to the Gap ACK blocks if any
1432 * @l: the tipc link
1433 * @hdr: the PROTOCOL/STATE_MSG header
1434 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1435 *
1436 * Return: the total Gap ACK blocks size
1437 */
1438u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1439 struct tipc_msg *hdr, bool uc)
1440{
1441 struct tipc_gap_ack_blks *p;
1442 u16 sz = 0;
1443
1444 /* Does peer support the Gap ACK blocks feature? */
1445 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1446 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1447 sz = ntohs(p->len);
1448 /* Sanity check */
1449 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1450 /* Good, check if the desired type exists */
1451 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1452 goto ok;
1453 /* Backward compatible: peer might not support bc, but uc? */
1454 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1455 if (p->ugack_cnt) {
1456 p->bgack_cnt = 0;
1457 goto ok;
1458 }
1459 }
1460 }
1461 /* Other cases: ignore! */
1462 p = NULL;
1463
1464ok:
1465 *ga = p;
1466 return sz;
1467}
1468
1469static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1470 struct tipc_link *l, u8 start_index)
1471{
1472 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1473 struct sk_buff *skb = skb_peek(&l->deferdq);
1474 u16 expect, seqno = 0;
1475 u8 n = 0;
1476
1477 if (!skb)
1478 return 0;
1479
1480 expect = buf_seqno(skb);
1481 skb_queue_walk(&l->deferdq, skb) {
1482 seqno = buf_seqno(skb);
1483 if (unlikely(more(seqno, expect))) {
1484 gacks[n].ack = htons(expect - 1);
1485 gacks[n].gap = htons(seqno - expect);
1486 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1487 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1488 l->name, n,
1489 skb_queue_len(&l->deferdq));
1490 return n;
1491 }
1492 } else if (unlikely(less(seqno, expect))) {
1493 pr_warn("Unexpected skb in deferdq!\n");
1494 continue;
1495 }
1496 expect = seqno + 1;
1497 }
1498
1499 /* last block */
1500 gacks[n].ack = htons(seqno);
1501 gacks[n].gap = 0;
1502 n++;
1503 return n;
1504}
1505
1506/* tipc_build_gap_ack_blks - build Gap ACK blocks
1507 * @l: tipc unicast link
1508 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1509 *
1510 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1511 * links of a certain peer, the buffer after built has the network data format
1512 * as found at the struct tipc_gap_ack_blks definition.
1513 *
1514 * returns the actual allocated memory size
1515 */
1516static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1517{
1518 struct tipc_link *bcl = l->bc_rcvlink;
1519 struct tipc_gap_ack_blks *ga;
1520 u16 len;
1521
1522 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1523
1524 /* Start with broadcast link first */
1525 tipc_bcast_lock(bcl->net);
1526 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1527 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1528 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1529 tipc_bcast_unlock(bcl->net);
1530
1531 /* Now for unicast link, but an explicit NACK only (???) */
1532 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1533 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1534
1535 /* Total len */
1536 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1537 ga->len = htons(len);
1538 return len;
1539}
1540
1541/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1542 * acked packets, also doing retransmissions if
1543 * gaps found
1544 * @l: tipc link with transmq queue to be advanced
1545 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1546 * @acked: seqno of last packet acked by peer without any gaps before
1547 * @gap: # of gap packets
1548 * @ga: buffer pointer to Gap ACK blocks from peer
1549 * @xmitq: queue for accumulating the retransmitted packets if any
1550 * @retransmitted: returned boolean value if a retransmission is really issued
1551 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1552 * happens (- unlikely case)
1553 *
1554 * Return: the number of packets released from the link transmq
1555 */
1556static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1557 u16 acked, u16 gap,
1558 struct tipc_gap_ack_blks *ga,
1559 struct sk_buff_head *xmitq,
1560 bool *retransmitted, int *rc)
1561{
1562 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1563 struct tipc_gap_ack *gacks = NULL;
1564 struct sk_buff *skb, *_skb, *tmp;
1565 struct tipc_msg *hdr;
1566 u32 qlen = skb_queue_len(&l->transmq);
1567 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1568 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1569 u16 ack = l->rcv_nxt - 1;
1570 u16 seqno, n = 0;
1571 u16 end = r->acked, start = end, offset = r->last_gap;
1572 u16 si = (last_ga) ? last_ga->start_index : 0;
1573 bool is_uc = !link_is_bc_sndlink(l);
1574 bool bc_has_acked = false;
1575
1576 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1577
1578 /* Determine Gap ACK blocks if any for the particular link */
1579 if (ga && is_uc) {
1580 /* Get the Gap ACKs, uc part */
1581 gack_cnt = ga->ugack_cnt;
1582 gacks = &ga->gacks[ga->bgack_cnt];
1583 } else if (ga) {
1584 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1585 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1586 GFP_ATOMIC);
1587 if (likely(this_ga)) {
1588 this_ga->start_index = 0;
1589 /* Start with the bc Gap ACKs */
1590 gack_cnt = this_ga->bgack_cnt;
1591 gacks = &this_ga->gacks[0];
1592 } else {
1593 /* Hmm, we can get in trouble..., simply ignore it */
1594 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1595 }
1596 }
1597
1598 /* Advance the link transmq */
1599 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1600 seqno = buf_seqno(skb);
1601
1602next_gap_ack:
1603 if (less_eq(seqno, nacked)) {
1604 if (is_uc)
1605 goto release;
1606 /* Skip packets peer has already acked */
1607 if (!more(seqno, r->acked))
1608 continue;
1609 /* Get the next of last Gap ACK blocks */
1610 while (more(seqno, end)) {
1611 if (!last_ga || si >= last_ga->bgack_cnt)
1612 break;
1613 start = end + offset + 1;
1614 end = ntohs(last_ga->gacks[si].ack);
1615 offset = ntohs(last_ga->gacks[si].gap);
1616 si++;
1617 WARN_ONCE(more(start, end) ||
1618 (!offset &&
1619 si < last_ga->bgack_cnt) ||
1620 si > MAX_GAP_ACK_BLKS,
1621 "Corrupted Gap ACK: %d %d %d %d %d\n",
1622 start, end, offset, si,
1623 last_ga->bgack_cnt);
1624 }
1625 /* Check against the last Gap ACK block */
1626 if (in_range(seqno, start, end))
1627 continue;
1628 /* Update/release the packet peer is acking */
1629 bc_has_acked = true;
1630 if (--TIPC_SKB_CB(skb)->ackers)
1631 continue;
1632release:
1633 /* release skb */
1634 __skb_unlink(skb, &l->transmq);
1635 kfree_skb(skb);
1636 } else if (less_eq(seqno, nacked + ngap)) {
1637 /* First gap: check if repeated retrans failures? */
1638 if (unlikely(seqno == acked + 1 &&
1639 link_retransmit_failure(l, r, rc))) {
1640 /* Ignore this bc Gap ACKs if any */
1641 kfree(this_ga);
1642 this_ga = NULL;
1643 break;
1644 }
1645 /* retransmit skb if unrestricted*/
1646 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1647 continue;
1648 tipc_link_set_skb_retransmit_time(skb, l);
1649 _skb = pskb_copy(skb, GFP_ATOMIC);
1650 if (!_skb)
1651 continue;
1652 hdr = buf_msg(_skb);
1653 msg_set_ack(hdr, ack);
1654 msg_set_bcast_ack(hdr, bc_ack);
1655 _skb->priority = TC_PRIO_CONTROL;
1656 __skb_queue_tail(xmitq, _skb);
1657 l->stats.retransmitted++;
1658 if (!is_uc)
1659 r->stats.retransmitted++;
1660 *retransmitted = true;
1661 /* Increase actual retrans counter & mark first time */
1662 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1663 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1664 } else {
1665 /* retry with Gap ACK blocks if any */
1666 if (n >= gack_cnt)
1667 break;
1668 nacked = ntohs(gacks[n].ack);
1669 ngap = ntohs(gacks[n].gap);
1670 n++;
1671 goto next_gap_ack;
1672 }
1673 }
1674
1675 /* Renew last Gap ACK blocks for bc if needed */
1676 if (bc_has_acked) {
1677 if (this_ga) {
1678 kfree(last_ga);
1679 r->last_ga = this_ga;
1680 r->last_gap = gap;
1681 } else if (last_ga) {
1682 if (less(acked, start)) {
1683 si--;
1684 offset = start - acked - 1;
1685 } else if (less(acked, end)) {
1686 acked = end;
1687 }
1688 if (si < last_ga->bgack_cnt) {
1689 last_ga->start_index = si;
1690 r->last_gap = offset;
1691 } else {
1692 kfree(last_ga);
1693 r->last_ga = NULL;
1694 r->last_gap = 0;
1695 }
1696 } else {
1697 r->last_gap = 0;
1698 }
1699 r->acked = acked;
1700 } else {
1701 kfree(this_ga);
1702 }
1703
1704 return qlen - skb_queue_len(&l->transmq);
1705}
1706
1707/* tipc_link_build_state_msg: prepare link state message for transmission
1708 *
1709 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1710 * risk of ack storms towards the sender
1711 */
1712int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1713{
1714 if (!l)
1715 return 0;
1716
1717 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1718 if (link_is_bc_rcvlink(l)) {
1719 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1720 return 0;
1721 l->rcv_unacked = 0;
1722
1723 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1724 l->snd_nxt = l->rcv_nxt;
1725 return TIPC_LINK_SND_STATE;
1726 }
1727 /* Unicast ACK */
1728 l->rcv_unacked = 0;
1729 l->stats.sent_acks++;
1730 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1731 return 0;
1732}
1733
1734/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1735 */
1736void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1737{
1738 int mtyp = RESET_MSG;
1739 struct sk_buff *skb;
1740
1741 if (l->state == LINK_ESTABLISHING)
1742 mtyp = ACTIVATE_MSG;
1743
1744 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1745
1746 /* Inform peer that this endpoint is going down if applicable */
1747 skb = skb_peek_tail(xmitq);
1748 if (skb && (l->state == LINK_RESET))
1749 msg_set_peer_stopping(buf_msg(skb), 1);
1750}
1751
1752/* tipc_link_build_nack_msg: prepare link nack message for transmission
1753 * Note that sending of broadcast NACK is coordinated among nodes, to
1754 * reduce the risk of NACK storms towards the sender
1755 */
1756static int tipc_link_build_nack_msg(struct tipc_link *l,
1757 struct sk_buff_head *xmitq)
1758{
1759 u32 def_cnt = ++l->stats.deferred_recv;
1760 struct sk_buff_head *dfq = &l->deferdq;
1761 u32 defq_len = skb_queue_len(dfq);
1762 int match1, match2;
1763
1764 if (link_is_bc_rcvlink(l)) {
1765 match1 = def_cnt & 0xf;
1766 match2 = tipc_own_addr(l->net) & 0xf;
1767 if (match1 == match2)
1768 return TIPC_LINK_SND_STATE;
1769 return 0;
1770 }
1771
1772 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1773 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1774
1775 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1776 rcvgap, 0, 0, xmitq);
1777 }
1778 return 0;
1779}
1780
1781/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1782 * @l: the link that should handle the message
1783 * @skb: TIPC packet
1784 * @xmitq: queue to place packets to be sent after this call
1785 */
1786int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1787 struct sk_buff_head *xmitq)
1788{
1789 struct sk_buff_head *defq = &l->deferdq;
1790 struct tipc_msg *hdr = buf_msg(skb);
1791 u16 seqno, rcv_nxt, win_lim;
1792 int released = 0;
1793 int rc = 0;
1794
1795 /* Verify and update link state */
1796 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1797 return tipc_link_proto_rcv(l, skb, xmitq);
1798
1799 /* Don't send probe at next timeout expiration */
1800 l->silent_intv_cnt = 0;
1801
1802 do {
1803 hdr = buf_msg(skb);
1804 seqno = msg_seqno(hdr);
1805 rcv_nxt = l->rcv_nxt;
1806 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1807
1808 if (unlikely(!link_is_up(l))) {
1809 if (l->state == LINK_ESTABLISHING)
1810 rc = TIPC_LINK_UP_EVT;
1811 kfree_skb(skb);
1812 break;
1813 }
1814
1815 /* Drop if outside receive window */
1816 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1817 l->stats.duplicates++;
1818 kfree_skb(skb);
1819 break;
1820 }
1821 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1822 NULL, NULL, NULL, NULL);
1823
1824 /* Defer delivery if sequence gap */
1825 if (unlikely(seqno != rcv_nxt)) {
1826 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1827 l->stats.duplicates++;
1828 rc |= tipc_link_build_nack_msg(l, xmitq);
1829 break;
1830 }
1831
1832 /* Deliver packet */
1833 l->rcv_nxt++;
1834 l->stats.recv_pkts++;
1835
1836 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1837 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1838 else if (!tipc_data_input(l, skb, l->inputq))
1839 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1840 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1841 rc |= tipc_link_build_state_msg(l, xmitq);
1842 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1843 break;
1844 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1845
1846 /* Forward queues and wake up waiting users */
1847 if (released) {
1848 tipc_link_update_cwin(l, released, 0);
1849 tipc_link_advance_backlog(l, xmitq);
1850 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1851 link_prepare_wakeup(l);
1852 }
1853 return rc;
1854}
1855
1856static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1857 bool probe_reply, u16 rcvgap,
1858 int tolerance, int priority,
1859 struct sk_buff_head *xmitq)
1860{
1861 struct tipc_mon_state *mstate = &l->mon_state;
1862 struct sk_buff_head *dfq = &l->deferdq;
1863 struct tipc_link *bcl = l->bc_rcvlink;
1864 struct tipc_msg *hdr;
1865 struct sk_buff *skb;
1866 bool node_up = link_is_up(bcl);
1867 u16 glen = 0, bc_rcvgap = 0;
1868 int dlen = 0;
1869 void *data;
1870
1871 /* Don't send protocol message during reset or link failover */
1872 if (tipc_link_is_blocked(l))
1873 return;
1874
1875 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1876 return;
1877
1878 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1879 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1880
1881 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1882 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1883 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1884 if (!skb)
1885 return;
1886
1887 hdr = buf_msg(skb);
1888 data = msg_data(hdr);
1889 msg_set_session(hdr, l->session);
1890 msg_set_bearer_id(hdr, l->bearer_id);
1891 msg_set_net_plane(hdr, l->net_plane);
1892 msg_set_next_sent(hdr, l->snd_nxt);
1893 msg_set_ack(hdr, l->rcv_nxt - 1);
1894 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1895 msg_set_bc_ack_invalid(hdr, !node_up);
1896 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1897 msg_set_link_tolerance(hdr, tolerance);
1898 msg_set_linkprio(hdr, priority);
1899 msg_set_redundant_link(hdr, node_up);
1900 msg_set_seq_gap(hdr, 0);
1901 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1902
1903 if (mtyp == STATE_MSG) {
1904 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1905 msg_set_seqno(hdr, l->snd_nxt_state++);
1906 msg_set_seq_gap(hdr, rcvgap);
1907 bc_rcvgap = link_bc_rcv_gap(bcl);
1908 msg_set_bc_gap(hdr, bc_rcvgap);
1909 msg_set_probe(hdr, probe);
1910 msg_set_is_keepalive(hdr, probe || probe_reply);
1911 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1912 glen = tipc_build_gap_ack_blks(l, hdr);
1913 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1914 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1915 skb_trim(skb, INT_H_SIZE + glen + dlen);
1916 l->stats.sent_states++;
1917 l->rcv_unacked = 0;
1918 } else {
1919 /* RESET_MSG or ACTIVATE_MSG */
1920 if (mtyp == ACTIVATE_MSG) {
1921 msg_set_dest_session_valid(hdr, 1);
1922 msg_set_dest_session(hdr, l->peer_session);
1923 }
1924 msg_set_max_pkt(hdr, l->advertised_mtu);
1925 strcpy(data, l->if_name);
1926 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1927 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1928 }
1929 if (probe)
1930 l->stats.sent_probes++;
1931 if (rcvgap)
1932 l->stats.sent_nacks++;
1933 if (bc_rcvgap)
1934 bcl->stats.sent_nacks++;
1935 skb->priority = TC_PRIO_CONTROL;
1936 __skb_queue_tail(xmitq, skb);
1937 trace_tipc_proto_build(skb, false, l->name);
1938}
1939
1940void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1941 struct sk_buff_head *xmitq)
1942{
1943 u32 onode = tipc_own_addr(l->net);
1944 struct tipc_msg *hdr, *ihdr;
1945 struct sk_buff_head tnlq;
1946 struct sk_buff *skb;
1947 u32 dnode = l->addr;
1948
1949 __skb_queue_head_init(&tnlq);
1950 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1951 INT_H_SIZE, BASIC_H_SIZE,
1952 dnode, onode, 0, 0, 0);
1953 if (!skb) {
1954 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1955 return;
1956 }
1957
1958 hdr = buf_msg(skb);
1959 msg_set_msgcnt(hdr, 1);
1960 msg_set_bearer_id(hdr, l->peer_bearer_id);
1961
1962 ihdr = (struct tipc_msg *)msg_data(hdr);
1963 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1964 BASIC_H_SIZE, dnode);
1965 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1966 __skb_queue_tail(&tnlq, skb);
1967 tipc_link_xmit(l, &tnlq, xmitq);
1968}
1969
1970/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1971 * with contents of the link's transmit and backlog queues.
1972 */
1973void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1974 int mtyp, struct sk_buff_head *xmitq)
1975{
1976 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1977 struct sk_buff *skb, *tnlskb;
1978 struct tipc_msg *hdr, tnlhdr;
1979 struct sk_buff_head *queue = &l->transmq;
1980 struct sk_buff_head tmpxq, tnlq, frags;
1981 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1982 bool pktcnt_need_update = false;
1983 u16 syncpt;
1984 int rc;
1985
1986 if (!tnl)
1987 return;
1988
1989 __skb_queue_head_init(&tnlq);
1990 /* Link Synching:
1991 * From now on, send only one single ("dummy") SYNCH message
1992 * to peer. The SYNCH message does not contain any data, just
1993 * a header conveying the synch point to the peer.
1994 */
1995 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1996 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1997 INT_H_SIZE, 0, l->addr,
1998 tipc_own_addr(l->net),
1999 0, 0, 0);
2000 if (!tnlskb) {
2001 pr_warn("%sunable to create dummy SYNCH_MSG\n",
2002 link_co_err);
2003 return;
2004 }
2005
2006 hdr = buf_msg(tnlskb);
2007 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
2008 msg_set_syncpt(hdr, syncpt);
2009 msg_set_bearer_id(hdr, l->peer_bearer_id);
2010 __skb_queue_tail(&tnlq, tnlskb);
2011 tipc_link_xmit(tnl, &tnlq, xmitq);
2012 return;
2013 }
2014
2015 __skb_queue_head_init(&tmpxq);
2016 __skb_queue_head_init(&frags);
2017 /* At least one packet required for safe algorithm => add dummy */
2018 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
2019 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
2020 0, 0, TIPC_ERR_NO_PORT);
2021 if (!skb) {
2022 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2023 return;
2024 }
2025 __skb_queue_tail(&tnlq, skb);
2026 tipc_link_xmit(l, &tnlq, &tmpxq);
2027 __skb_queue_purge(&tmpxq);
2028
2029 /* Initialize reusable tunnel packet header */
2030 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2031 mtyp, INT_H_SIZE, l->addr);
2032 if (mtyp == SYNCH_MSG)
2033 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2034 else
2035 pktcnt = skb_queue_len(&l->transmq);
2036 pktcnt += skb_queue_len(&l->backlogq);
2037 msg_set_msgcnt(&tnlhdr, pktcnt);
2038 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2039tnl:
2040 /* Wrap each packet into a tunnel packet */
2041 skb_queue_walk(queue, skb) {
2042 hdr = buf_msg(skb);
2043 if (queue == &l->backlogq)
2044 msg_set_seqno(hdr, seqno++);
2045 pktlen = msg_size(hdr);
2046
2047 /* Tunnel link MTU is not large enough? This could be
2048 * due to:
2049 * 1) Link MTU has just changed or set differently;
2050 * 2) Or FAILOVER on the top of a SYNCH message
2051 *
2052 * The 2nd case should not happen if peer supports
2053 * TIPC_TUNNEL_ENHANCED
2054 */
2055 if (pktlen > tnl->mtu - INT_H_SIZE) {
2056 if (mtyp == FAILOVER_MSG &&
2057 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2058 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2059 &frags);
2060 if (rc) {
2061 pr_warn("%sunable to frag msg: rc %d\n",
2062 link_co_err, rc);
2063 return;
2064 }
2065 pktcnt += skb_queue_len(&frags) - 1;
2066 pktcnt_need_update = true;
2067 skb_queue_splice_tail_init(&frags, &tnlq);
2068 continue;
2069 }
2070 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2071 * => Just warn it and return!
2072 */
2073 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2074 link_co_err, msg_user(hdr),
2075 msg_type(hdr), msg_size(hdr));
2076 return;
2077 }
2078
2079 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2080 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2081 if (!tnlskb) {
2082 pr_warn("%sunable to send packet\n", link_co_err);
2083 return;
2084 }
2085 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2086 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2087 __skb_queue_tail(&tnlq, tnlskb);
2088 }
2089 if (queue != &l->backlogq) {
2090 queue = &l->backlogq;
2091 goto tnl;
2092 }
2093
2094 if (pktcnt_need_update)
2095 skb_queue_walk(&tnlq, skb) {
2096 hdr = buf_msg(skb);
2097 msg_set_msgcnt(hdr, pktcnt);
2098 }
2099
2100 tipc_link_xmit(tnl, &tnlq, xmitq);
2101
2102 if (mtyp == FAILOVER_MSG) {
2103 tnl->drop_point = l->rcv_nxt;
2104 tnl->failover_reasm_skb = l->reasm_buf;
2105 l->reasm_buf = NULL;
2106
2107 /* Failover the link's deferdq */
2108 if (unlikely(!skb_queue_empty(fdefq))) {
2109 pr_warn("Link failover deferdq not empty: %d!\n",
2110 skb_queue_len(fdefq));
2111 __skb_queue_purge(fdefq);
2112 }
2113 skb_queue_splice_init(&l->deferdq, fdefq);
2114 }
2115}
2116
2117/**
2118 * tipc_link_failover_prepare() - prepare tnl for link failover
2119 *
2120 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2121 * see the tipc_node_link_failover() for details
2122 *
2123 * @l: failover link
2124 * @tnl: tunnel link
2125 * @xmitq: queue for messages to be xmited
2126 */
2127void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2128 struct sk_buff_head *xmitq)
2129{
2130 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2131
2132 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2133
2134 /* This failover link endpoint was never established before,
2135 * so it has not received anything from peer.
2136 * Otherwise, it must be a normal failover situation or the
2137 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2138 * would have to start over from scratch instead.
2139 */
2140 tnl->drop_point = 1;
2141 tnl->failover_reasm_skb = NULL;
2142
2143 /* Initiate the link's failover deferdq */
2144 if (unlikely(!skb_queue_empty(fdefq))) {
2145 pr_warn("Link failover deferdq not empty: %d!\n",
2146 skb_queue_len(fdefq));
2147 __skb_queue_purge(fdefq);
2148 }
2149}
2150
2151/* tipc_link_validate_msg(): validate message against current link state
2152 * Returns true if message should be accepted, otherwise false
2153 */
2154bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2155{
2156 u16 curr_session = l->peer_session;
2157 u16 session = msg_session(hdr);
2158 int mtyp = msg_type(hdr);
2159
2160 if (msg_user(hdr) != LINK_PROTOCOL)
2161 return true;
2162
2163 switch (mtyp) {
2164 case RESET_MSG:
2165 if (!l->in_session)
2166 return true;
2167 /* Accept only RESET with new session number */
2168 return more(session, curr_session);
2169 case ACTIVATE_MSG:
2170 if (!l->in_session)
2171 return true;
2172 /* Accept only ACTIVATE with new or current session number */
2173 return !less(session, curr_session);
2174 case STATE_MSG:
2175 /* Accept only STATE with current session number */
2176 if (!l->in_session)
2177 return false;
2178 if (session != curr_session)
2179 return false;
2180 /* Extra sanity check */
2181 if (!link_is_up(l) && msg_ack(hdr))
2182 return false;
2183 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2184 return true;
2185 /* Accept only STATE with new sequence number */
2186 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2187 default:
2188 return false;
2189 }
2190}
2191
2192/* tipc_link_proto_rcv(): receive link level protocol message :
2193 * Note that network plane id propagates through the network, and may
2194 * change at any time. The node with lowest numerical id determines
2195 * network plane
2196 */
2197static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2198 struct sk_buff_head *xmitq)
2199{
2200 struct tipc_msg *hdr = buf_msg(skb);
2201 struct tipc_gap_ack_blks *ga = NULL;
2202 bool reply = msg_probe(hdr), retransmitted = false;
2203 u32 dlen = msg_data_sz(hdr), glen = 0;
2204 u16 peers_snd_nxt = msg_next_sent(hdr);
2205 u16 peers_tol = msg_link_tolerance(hdr);
2206 u16 peers_prio = msg_linkprio(hdr);
2207 u16 gap = msg_seq_gap(hdr);
2208 u16 ack = msg_ack(hdr);
2209 u16 rcv_nxt = l->rcv_nxt;
2210 u16 rcvgap = 0;
2211 int mtyp = msg_type(hdr);
2212 int rc = 0, released;
2213 char *if_name;
2214 void *data;
2215
2216 trace_tipc_proto_rcv(skb, false, l->name);
2217
2218 if (dlen > U16_MAX)
2219 goto exit;
2220
2221 if (tipc_link_is_blocked(l) || !xmitq)
2222 goto exit;
2223
2224 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2225 l->net_plane = msg_net_plane(hdr);
2226
2227 if (skb_linearize(skb))
2228 goto exit;
2229
2230 hdr = buf_msg(skb);
2231 data = msg_data(hdr);
2232
2233 if (!tipc_link_validate_msg(l, hdr)) {
2234 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2235 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2236 goto exit;
2237 }
2238
2239 switch (mtyp) {
2240 case RESET_MSG:
2241 case ACTIVATE_MSG:
2242 /* Complete own link name with peer's interface name */
2243 if_name = strrchr(l->name, ':') + 1;
2244 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2245 break;
2246 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2247 break;
2248 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2249
2250 /* Update own tolerance if peer indicates a non-zero value */
2251 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2252 l->tolerance = peers_tol;
2253 l->bc_rcvlink->tolerance = peers_tol;
2254 }
2255 /* Update own priority if peer's priority is higher */
2256 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2257 l->priority = peers_prio;
2258
2259 /* If peer is going down we want full re-establish cycle */
2260 if (msg_peer_stopping(hdr)) {
2261 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2262 break;
2263 }
2264
2265 /* If this endpoint was re-created while peer was ESTABLISHING
2266 * it doesn't know current session number. Force re-synch.
2267 */
2268 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2269 l->session != msg_dest_session(hdr)) {
2270 if (less(l->session, msg_dest_session(hdr)))
2271 l->session = msg_dest_session(hdr) + 1;
2272 break;
2273 }
2274
2275 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2276 if (mtyp == RESET_MSG || !link_is_up(l))
2277 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2278
2279 /* ACTIVATE_MSG takes up link if it was already locally reset */
2280 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2281 rc = TIPC_LINK_UP_EVT;
2282
2283 l->peer_session = msg_session(hdr);
2284 l->in_session = true;
2285 l->peer_bearer_id = msg_bearer_id(hdr);
2286 if (l->mtu > msg_max_pkt(hdr))
2287 l->mtu = msg_max_pkt(hdr);
2288 break;
2289
2290 case STATE_MSG:
2291 /* Validate Gap ACK blocks, drop if invalid */
2292 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2293 if (glen > dlen)
2294 break;
2295
2296 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2297
2298 /* Update own tolerance if peer indicates a non-zero value */
2299 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2300 l->tolerance = peers_tol;
2301 l->bc_rcvlink->tolerance = peers_tol;
2302 }
2303 /* Update own prio if peer indicates a different value */
2304 if ((peers_prio != l->priority) &&
2305 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2306 l->priority = peers_prio;
2307 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2308 }
2309
2310 l->silent_intv_cnt = 0;
2311 l->stats.recv_states++;
2312 if (msg_probe(hdr))
2313 l->stats.recv_probes++;
2314
2315 if (!link_is_up(l)) {
2316 if (l->state == LINK_ESTABLISHING)
2317 rc = TIPC_LINK_UP_EVT;
2318 break;
2319 }
2320
2321 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2322 &l->mon_state, l->bearer_id);
2323
2324 /* Send NACK if peer has sent pkts we haven't received yet */
2325 if ((reply || msg_is_keepalive(hdr)) &&
2326 more(peers_snd_nxt, rcv_nxt) &&
2327 !tipc_link_is_synching(l) &&
2328 skb_queue_empty(&l->deferdq))
2329 rcvgap = peers_snd_nxt - l->rcv_nxt;
2330 if (rcvgap || reply)
2331 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2332 rcvgap, 0, 0, xmitq);
2333
2334 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2335 &retransmitted, &rc);
2336 if (gap)
2337 l->stats.recv_nacks++;
2338 if (released || retransmitted)
2339 tipc_link_update_cwin(l, released, retransmitted);
2340 if (released)
2341 tipc_link_advance_backlog(l, xmitq);
2342 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2343 link_prepare_wakeup(l);
2344 }
2345exit:
2346 kfree_skb(skb);
2347 return rc;
2348}
2349
2350/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2351 */
2352static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2353 u16 peers_snd_nxt,
2354 struct sk_buff_head *xmitq)
2355{
2356 struct sk_buff *skb;
2357 struct tipc_msg *hdr;
2358 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2359 u16 ack = l->rcv_nxt - 1;
2360 u16 gap_to = peers_snd_nxt - 1;
2361
2362 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2363 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2364 if (!skb)
2365 return false;
2366 hdr = buf_msg(skb);
2367 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2368 msg_set_bcast_ack(hdr, ack);
2369 msg_set_bcgap_after(hdr, ack);
2370 if (dfrd_skb)
2371 gap_to = buf_seqno(dfrd_skb) - 1;
2372 msg_set_bcgap_to(hdr, gap_to);
2373 msg_set_non_seq(hdr, bcast);
2374 __skb_queue_tail(xmitq, skb);
2375 return true;
2376}
2377
2378/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2379 *
2380 * Give a newly added peer node the sequence number where it should
2381 * start receiving and acking broadcast packets.
2382 */
2383static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2384 struct sk_buff_head *xmitq)
2385{
2386 struct sk_buff_head list;
2387
2388 __skb_queue_head_init(&list);
2389 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2390 return;
2391 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2392 tipc_link_xmit(l, &list, xmitq);
2393}
2394
2395/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2396 */
2397void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2398{
2399 int mtyp = msg_type(hdr);
2400 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2401
2402 if (link_is_up(l))
2403 return;
2404
2405 if (msg_user(hdr) == BCAST_PROTOCOL) {
2406 l->rcv_nxt = peers_snd_nxt;
2407 l->state = LINK_ESTABLISHED;
2408 return;
2409 }
2410
2411 if (l->peer_caps & TIPC_BCAST_SYNCH)
2412 return;
2413
2414 if (msg_peer_node_is_up(hdr))
2415 return;
2416
2417 /* Compatibility: accept older, less safe initial synch data */
2418 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2419 l->rcv_nxt = peers_snd_nxt;
2420}
2421
2422/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2423 */
2424int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2425 struct sk_buff_head *xmitq)
2426{
2427 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2428 int rc = 0;
2429
2430 if (!link_is_up(l))
2431 return rc;
2432
2433 if (!msg_peer_node_is_up(hdr))
2434 return rc;
2435
2436 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2437 if (msg_ack(hdr))
2438 l->bc_peer_is_up = true;
2439
2440 if (!l->bc_peer_is_up)
2441 return rc;
2442
2443 /* Ignore if peers_snd_nxt goes beyond receive window */
2444 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2445 return rc;
2446
2447 l->snd_nxt = peers_snd_nxt;
2448 if (link_bc_rcv_gap(l))
2449 rc |= TIPC_LINK_SND_STATE;
2450
2451 /* Return now if sender supports nack via STATE messages */
2452 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2453 return rc;
2454
2455 /* Otherwise, be backwards compatible */
2456
2457 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2458 l->nack_state = BC_NACK_SND_CONDITIONAL;
2459 return 0;
2460 }
2461
2462 /* Don't NACK if one was recently sent or peeked */
2463 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2464 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2465 return 0;
2466 }
2467
2468 /* Conditionally delay NACK sending until next synch rcv */
2469 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2470 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2471 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2472 return 0;
2473 }
2474
2475 /* Send NACK now but suppress next one */
2476 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2477 l->nack_state = BC_NACK_SND_SUPPRESS;
2478 return 0;
2479}
2480
2481int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2482 struct tipc_gap_ack_blks *ga,
2483 struct sk_buff_head *xmitq,
2484 struct sk_buff_head *retrq)
2485{
2486 struct tipc_link *l = r->bc_sndlink;
2487 bool unused = false;
2488 int rc = 0;
2489
2490 if (!link_is_up(r) || !r->bc_peer_is_up)
2491 return 0;
2492
2493 if (gap) {
2494 l->stats.recv_nacks++;
2495 r->stats.recv_nacks++;
2496 }
2497
2498 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2499 return 0;
2500
2501 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2502 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2503
2504 tipc_link_advance_backlog(l, xmitq);
2505 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2506 link_prepare_wakeup(l);
2507
2508 return rc;
2509}
2510
2511/* tipc_link_bc_nack_rcv(): receive broadcast nack message
2512 * This function is here for backwards compatibility, since
2513 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2514 */
2515int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2516 struct sk_buff_head *xmitq)
2517{
2518 struct tipc_msg *hdr = buf_msg(skb);
2519 u32 dnode = msg_destnode(hdr);
2520 int mtyp = msg_type(hdr);
2521 u16 acked = msg_bcast_ack(hdr);
2522 u16 from = acked + 1;
2523 u16 to = msg_bcgap_to(hdr);
2524 u16 peers_snd_nxt = to + 1;
2525 int rc = 0;
2526
2527 kfree_skb(skb);
2528
2529 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2530 return 0;
2531
2532 if (mtyp != STATE_MSG)
2533 return 0;
2534
2535 if (dnode == tipc_own_addr(l->net)) {
2536 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2537 xmitq);
2538 l->stats.recv_nacks++;
2539 return rc;
2540 }
2541
2542 /* Msg for other node => suppress own NACK at next sync if applicable */
2543 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2544 l->nack_state = BC_NACK_SND_SUPPRESS;
2545
2546 return 0;
2547}
2548
2549void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2550{
2551 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2552
2553 l->min_win = min_win;
2554 l->ssthresh = max_win;
2555 l->max_win = max_win;
2556 l->window = min_win;
2557 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2558 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2559 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2560 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2561 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2562}
2563
2564/**
2565 * tipc_link_reset_stats - reset link statistics
2566 * @l: pointer to link
2567 */
2568void tipc_link_reset_stats(struct tipc_link *l)
2569{
2570 memset(&l->stats, 0, sizeof(l->stats));
2571}
2572
2573static void link_print(struct tipc_link *l, const char *str)
2574{
2575 struct sk_buff *hskb = skb_peek(&l->transmq);
2576 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2577 u16 tail = l->snd_nxt - 1;
2578
2579 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2580 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2581 skb_queue_len(&l->transmq), head, tail,
2582 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2583}
2584
2585/* Parse and validate nested (link) properties valid for media, bearer and link
2586 */
2587int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2588{
2589 int err;
2590
2591 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2592 tipc_nl_prop_policy, NULL);
2593 if (err)
2594 return err;
2595
2596 if (props[TIPC_NLA_PROP_PRIO]) {
2597 u32 prio;
2598
2599 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2600 if (prio > TIPC_MAX_LINK_PRI)
2601 return -EINVAL;
2602 }
2603
2604 if (props[TIPC_NLA_PROP_TOL]) {
2605 u32 tol;
2606
2607 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2608 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2609 return -EINVAL;
2610 }
2611
2612 if (props[TIPC_NLA_PROP_WIN]) {
2613 u32 max_win;
2614
2615 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2616 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2617 return -EINVAL;
2618 }
2619
2620 return 0;
2621}
2622
2623static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2624{
2625 int i;
2626 struct nlattr *stats;
2627
2628 struct nla_map {
2629 u32 key;
2630 u32 val;
2631 };
2632
2633 struct nla_map map[] = {
2634 {TIPC_NLA_STATS_RX_INFO, 0},
2635 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2636 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2637 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2638 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2639 {TIPC_NLA_STATS_TX_INFO, 0},
2640 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2641 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2642 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2643 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2644 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2645 s->msg_length_counts : 1},
2646 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2647 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2648 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2649 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2650 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2651 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2652 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2653 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2654 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2655 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2656 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2657 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2658 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2659 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2660 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2661 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2662 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2663 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2664 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2665 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2666 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2667 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2668 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2669 };
2670
2671 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2672 if (!stats)
2673 return -EMSGSIZE;
2674
2675 for (i = 0; i < ARRAY_SIZE(map); i++)
2676 if (nla_put_u32(skb, map[i].key, map[i].val))
2677 goto msg_full;
2678
2679 nla_nest_end(skb, stats);
2680
2681 return 0;
2682msg_full:
2683 nla_nest_cancel(skb, stats);
2684
2685 return -EMSGSIZE;
2686}
2687
2688/* Caller should hold appropriate locks to protect the link */
2689int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2690 struct tipc_link *link, int nlflags)
2691{
2692 u32 self = tipc_own_addr(net);
2693 struct nlattr *attrs;
2694 struct nlattr *prop;
2695 void *hdr;
2696 int err;
2697
2698 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2699 nlflags, TIPC_NL_LINK_GET);
2700 if (!hdr)
2701 return -EMSGSIZE;
2702
2703 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2704 if (!attrs)
2705 goto msg_full;
2706
2707 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2708 goto attr_msg_full;
2709 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2710 goto attr_msg_full;
2711 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2712 goto attr_msg_full;
2713 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2714 goto attr_msg_full;
2715 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2716 goto attr_msg_full;
2717
2718 if (tipc_link_is_up(link))
2719 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2720 goto attr_msg_full;
2721 if (link->active)
2722 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2723 goto attr_msg_full;
2724
2725 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2726 if (!prop)
2727 goto attr_msg_full;
2728 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2729 goto prop_msg_full;
2730 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2731 goto prop_msg_full;
2732 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2733 link->window))
2734 goto prop_msg_full;
2735 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2736 goto prop_msg_full;
2737 nla_nest_end(msg->skb, prop);
2738
2739 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2740 if (err)
2741 goto attr_msg_full;
2742
2743 nla_nest_end(msg->skb, attrs);
2744 genlmsg_end(msg->skb, hdr);
2745
2746 return 0;
2747
2748prop_msg_full:
2749 nla_nest_cancel(msg->skb, prop);
2750attr_msg_full:
2751 nla_nest_cancel(msg->skb, attrs);
2752msg_full:
2753 genlmsg_cancel(msg->skb, hdr);
2754
2755 return -EMSGSIZE;
2756}
2757
2758static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2759 struct tipc_stats *stats)
2760{
2761 int i;
2762 struct nlattr *nest;
2763
2764 struct nla_map {
2765 __u32 key;
2766 __u32 val;
2767 };
2768
2769 struct nla_map map[] = {
2770 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2771 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2772 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2773 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2774 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2775 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2776 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2777 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2778 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2779 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2780 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2781 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2782 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2783 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2784 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2785 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2786 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2787 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2788 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2789 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2790 };
2791
2792 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2793 if (!nest)
2794 return -EMSGSIZE;
2795
2796 for (i = 0; i < ARRAY_SIZE(map); i++)
2797 if (nla_put_u32(skb, map[i].key, map[i].val))
2798 goto msg_full;
2799
2800 nla_nest_end(skb, nest);
2801
2802 return 0;
2803msg_full:
2804 nla_nest_cancel(skb, nest);
2805
2806 return -EMSGSIZE;
2807}
2808
2809int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2810 struct tipc_link *bcl)
2811{
2812 int err;
2813 void *hdr;
2814 struct nlattr *attrs;
2815 struct nlattr *prop;
2816 u32 bc_mode = tipc_bcast_get_mode(net);
2817 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2818
2819 if (!bcl)
2820 return 0;
2821
2822 tipc_bcast_lock(net);
2823
2824 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2825 NLM_F_MULTI, TIPC_NL_LINK_GET);
2826 if (!hdr) {
2827 tipc_bcast_unlock(net);
2828 return -EMSGSIZE;
2829 }
2830
2831 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2832 if (!attrs)
2833 goto msg_full;
2834
2835 /* The broadcast link is always up */
2836 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2837 goto attr_msg_full;
2838
2839 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2840 goto attr_msg_full;
2841 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2842 goto attr_msg_full;
2843 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2844 goto attr_msg_full;
2845 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2846 goto attr_msg_full;
2847
2848 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2849 if (!prop)
2850 goto attr_msg_full;
2851 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2852 goto prop_msg_full;
2853 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2854 goto prop_msg_full;
2855 if (bc_mode & BCLINK_MODE_SEL)
2856 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2857 bc_ratio))
2858 goto prop_msg_full;
2859 nla_nest_end(msg->skb, prop);
2860
2861 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2862 if (err)
2863 goto attr_msg_full;
2864
2865 tipc_bcast_unlock(net);
2866 nla_nest_end(msg->skb, attrs);
2867 genlmsg_end(msg->skb, hdr);
2868
2869 return 0;
2870
2871prop_msg_full:
2872 nla_nest_cancel(msg->skb, prop);
2873attr_msg_full:
2874 nla_nest_cancel(msg->skb, attrs);
2875msg_full:
2876 tipc_bcast_unlock(net);
2877 genlmsg_cancel(msg->skb, hdr);
2878
2879 return -EMSGSIZE;
2880}
2881
2882void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2883 struct sk_buff_head *xmitq)
2884{
2885 l->tolerance = tol;
2886 if (l->bc_rcvlink)
2887 l->bc_rcvlink->tolerance = tol;
2888 if (link_is_up(l))
2889 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2890}
2891
2892void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2893 struct sk_buff_head *xmitq)
2894{
2895 l->priority = prio;
2896 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2897}
2898
2899void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2900{
2901 l->abort_limit = limit;
2902}
2903
2904/**
2905 * tipc_link_dump - dump TIPC link data
2906 * @l: tipc link to be dumped
2907 * @dqueues: bitmask to decide if any link queue to be dumped?
2908 * - TIPC_DUMP_NONE: don't dump link queues
2909 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2910 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2911 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2912 * - TIPC_DUMP_INPUTQ: dump link input queue
2913 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2914 * - TIPC_DUMP_ALL: dump all the link queues above
2915 * @buf: returned buffer of dump data in format
2916 */
2917int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2918{
2919 int i = 0;
2920 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2921 struct sk_buff_head *list;
2922 struct sk_buff *hskb, *tskb;
2923 u32 len;
2924
2925 if (!l) {
2926 i += scnprintf(buf, sz, "link data: (null)\n");
2927 return i;
2928 }
2929
2930 i += scnprintf(buf, sz, "link data: %x", l->addr);
2931 i += scnprintf(buf + i, sz - i, " %x", l->state);
2932 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2933 i += scnprintf(buf + i, sz - i, " %u", l->session);
2934 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2935 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2936 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2937 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2938 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2939 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2940 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2941 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2942 i += scnprintf(buf + i, sz - i, " %u", 0);
2943 i += scnprintf(buf + i, sz - i, " %u", 0);
2944 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2945
2946 list = &l->transmq;
2947 len = skb_queue_len(list);
2948 hskb = skb_peek(list);
2949 tskb = skb_peek_tail(list);
2950 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2951 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2952 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2953
2954 list = &l->deferdq;
2955 len = skb_queue_len(list);
2956 hskb = skb_peek(list);
2957 tskb = skb_peek_tail(list);
2958 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2959 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2960 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2961
2962 list = &l->backlogq;
2963 len = skb_queue_len(list);
2964 hskb = skb_peek(list);
2965 tskb = skb_peek_tail(list);
2966 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2967 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2968 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2969
2970 list = l->inputq;
2971 len = skb_queue_len(list);
2972 hskb = skb_peek(list);
2973 tskb = skb_peek_tail(list);
2974 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2975 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2976 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2977
2978 if (dqueues & TIPC_DUMP_TRANSMQ) {
2979 i += scnprintf(buf + i, sz - i, "transmq: ");
2980 i += tipc_list_dump(&l->transmq, false, buf + i);
2981 }
2982 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2983 i += scnprintf(buf + i, sz - i,
2984 "backlogq: <%u %u %u %u %u>, ",
2985 l->backlog[TIPC_LOW_IMPORTANCE].len,
2986 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2987 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2988 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2989 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2990 i += tipc_list_dump(&l->backlogq, false, buf + i);
2991 }
2992 if (dqueues & TIPC_DUMP_DEFERDQ) {
2993 i += scnprintf(buf + i, sz - i, "deferdq: ");
2994 i += tipc_list_dump(&l->deferdq, false, buf + i);
2995 }
2996 if (dqueues & TIPC_DUMP_INPUTQ) {
2997 i += scnprintf(buf + i, sz - i, "inputq: ");
2998 i += tipc_list_dump(l->inputq, false, buf + i);
2999 }
3000 if (dqueues & TIPC_DUMP_WAKEUP) {
3001 i += scnprintf(buf + i, sz - i, "wakeup: ");
3002 i += tipc_list_dump(&l->wakeupq, false, buf + i);
3003 }
3004
3005 return i;
3006}
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
46#include <linux/pkt_sched.h>
47
48struct tipc_stats {
49 u32 sent_info; /* used in counting # sent packets */
50 u32 recv_info; /* used in counting # recv'd packets */
51 u32 sent_states;
52 u32 recv_states;
53 u32 sent_probes;
54 u32 recv_probes;
55 u32 sent_nacks;
56 u32 recv_nacks;
57 u32 sent_acks;
58 u32 sent_bundled;
59 u32 sent_bundles;
60 u32 recv_bundled;
61 u32 recv_bundles;
62 u32 retransmitted;
63 u32 sent_fragmented;
64 u32 sent_fragments;
65 u32 recv_fragmented;
66 u32 recv_fragments;
67 u32 link_congs; /* # port sends blocked by congestion */
68 u32 deferred_recv;
69 u32 duplicates;
70 u32 max_queue_sz; /* send queue size high water mark */
71 u32 accu_queue_sz; /* used for send queue size profiling */
72 u32 queue_sz_counts; /* used for send queue size profiling */
73 u32 msg_length_counts; /* used for message length profiling */
74 u32 msg_lengths_total; /* used for message length profiling */
75 u32 msg_length_profile[7]; /* used for msg. length profiling */
76};
77
78/**
79 * struct tipc_link - TIPC link data structure
80 * @addr: network address of link's peer node
81 * @name: link name character string
82 * @media_addr: media address to use when sending messages over link
83 * @timer: link timer
84 * @net: pointer to namespace struct
85 * @refcnt: reference counter for permanent references (owner node & timer)
86 * @peer_session: link session # being used by peer end of link
87 * @peer_bearer_id: bearer id used by link's peer endpoint
88 * @bearer_id: local bearer id used by link
89 * @tolerance: minimum link continuity loss needed to reset link [in ms]
90 * @keepalive_intv: link keepalive timer interval
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 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
100 * @exp_msg_count: # of tunnelled messages expected during link changeover
101 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
102 * @mtu: current maximum packet size for this link
103 * @advertised_mtu: advertised own mtu when link is being established
104 * @transmitq: queue for sent, non-acked messages
105 * @backlogq: queue for messages waiting to be sent
106 * @snt_nxt: next sequence number to use for outbound messages
107 * @last_retransmitted: sequence number of most recently retransmitted message
108 * @stale_count: # of identical retransmit requests made by peer
109 * @ackers: # of peers that needs to ack each packet before it can be released
110 * @acked: # last packet acked by a certain peer. Used for broadcast.
111 * @rcv_nxt: next sequence number to expect for inbound messages
112 * @deferred_queue: deferred queue saved OOS b'cast message received from node
113 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
114 * @inputq: buffer queue for messages to be delivered upwards
115 * @namedq: buffer queue for name table messages to be delivered upwards
116 * @next_out: ptr to first unsent outbound message in queue
117 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
118 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
119 * @reasm_buf: head of partially reassembled inbound message fragments
120 * @bc_rcvr: marks that this is a broadcast receiver link
121 * @stats: collects statistics regarding link activity
122 */
123struct tipc_link {
124 u32 addr;
125 char name[TIPC_MAX_LINK_NAME];
126 struct net *net;
127
128 /* Management and link supervision data */
129 u32 peer_session;
130 u32 session;
131 u32 peer_bearer_id;
132 u32 bearer_id;
133 u32 tolerance;
134 unsigned long keepalive_intv;
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
144 /* Failover/synch */
145 u16 drop_point;
146 struct sk_buff *failover_reasm_skb;
147
148 /* Max packet negotiation */
149 u16 mtu;
150 u16 advertised_mtu;
151
152 /* Sending */
153 struct sk_buff_head transmq;
154 struct sk_buff_head backlogq;
155 struct {
156 u16 len;
157 u16 limit;
158 } backlog[5];
159 u16 snd_nxt;
160 u16 last_retransm;
161 u16 window;
162 u32 stale_count;
163
164 /* Reception */
165 u16 rcv_nxt;
166 u32 rcv_unacked;
167 struct sk_buff_head deferdq;
168 struct sk_buff_head *inputq;
169 struct sk_buff_head *namedq;
170
171 /* Congestion handling */
172 struct sk_buff_head wakeupq;
173
174 /* Fragmentation/reassembly */
175 struct sk_buff *reasm_buf;
176
177 /* Broadcast */
178 u16 ackers;
179 u16 acked;
180 struct tipc_link *bc_rcvlink;
181 struct tipc_link *bc_sndlink;
182 int nack_state;
183 bool bc_peer_is_up;
184
185 /* Statistics */
186 struct tipc_stats stats;
187};
188
189/*
190 * Error message prefixes
191 */
192static const char *link_co_err = "Link tunneling error, ";
193static const char *link_rst_msg = "Resetting link ";
194
195/* Send states for broadcast NACKs
196 */
197enum {
198 BC_NACK_SND_CONDITIONAL,
199 BC_NACK_SND_UNCONDITIONAL,
200 BC_NACK_SND_SUPPRESS,
201};
202
203/*
204 * Interval between NACKs when packets arrive out of order
205 */
206#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
207
208/* Wildcard value for link session numbers. When it is known that
209 * peer endpoint is down, any session number must be accepted.
210 */
211#define ANY_SESSION 0x10000
212
213/* Link FSM states:
214 */
215enum {
216 LINK_ESTABLISHED = 0xe,
217 LINK_ESTABLISHING = 0xe << 4,
218 LINK_RESET = 0x1 << 8,
219 LINK_RESETTING = 0x2 << 12,
220 LINK_PEER_RESET = 0xd << 16,
221 LINK_FAILINGOVER = 0xf << 20,
222 LINK_SYNCHING = 0xc << 24
223};
224
225/* Link FSM state checking routines
226 */
227static int link_is_up(struct tipc_link *l)
228{
229 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
230}
231
232static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
233 struct sk_buff_head *xmitq);
234static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
235 u16 rcvgap, int tolerance, int priority,
236 struct sk_buff_head *xmitq);
237static void link_print(struct tipc_link *l, const char *str);
238static void tipc_link_build_nack_msg(struct tipc_link *l,
239 struct sk_buff_head *xmitq);
240static void tipc_link_build_bc_init_msg(struct tipc_link *l,
241 struct sk_buff_head *xmitq);
242static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
243
244/*
245 * Simple non-static link routines (i.e. referenced outside this file)
246 */
247bool tipc_link_is_up(struct tipc_link *l)
248{
249 return link_is_up(l);
250}
251
252bool tipc_link_peer_is_down(struct tipc_link *l)
253{
254 return l->state == LINK_PEER_RESET;
255}
256
257bool tipc_link_is_reset(struct tipc_link *l)
258{
259 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
260}
261
262bool tipc_link_is_establishing(struct tipc_link *l)
263{
264 return l->state == LINK_ESTABLISHING;
265}
266
267bool tipc_link_is_synching(struct tipc_link *l)
268{
269 return l->state == LINK_SYNCHING;
270}
271
272bool tipc_link_is_failingover(struct tipc_link *l)
273{
274 return l->state == LINK_FAILINGOVER;
275}
276
277bool tipc_link_is_blocked(struct tipc_link *l)
278{
279 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
280}
281
282static bool link_is_bc_sndlink(struct tipc_link *l)
283{
284 return !l->bc_sndlink;
285}
286
287static bool link_is_bc_rcvlink(struct tipc_link *l)
288{
289 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
290}
291
292int tipc_link_is_active(struct tipc_link *l)
293{
294 return l->active;
295}
296
297void tipc_link_set_active(struct tipc_link *l, bool active)
298{
299 l->active = active;
300}
301
302u32 tipc_link_id(struct tipc_link *l)
303{
304 return l->peer_bearer_id << 16 | l->bearer_id;
305}
306
307int tipc_link_window(struct tipc_link *l)
308{
309 return l->window;
310}
311
312int tipc_link_prio(struct tipc_link *l)
313{
314 return l->priority;
315}
316
317unsigned long tipc_link_tolerance(struct tipc_link *l)
318{
319 return l->tolerance;
320}
321
322struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
323{
324 return l->inputq;
325}
326
327char tipc_link_plane(struct tipc_link *l)
328{
329 return l->net_plane;
330}
331
332void tipc_link_add_bc_peer(struct tipc_link *snd_l,
333 struct tipc_link *uc_l,
334 struct sk_buff_head *xmitq)
335{
336 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
337
338 snd_l->ackers++;
339 rcv_l->acked = snd_l->snd_nxt - 1;
340 snd_l->state = LINK_ESTABLISHED;
341 tipc_link_build_bc_init_msg(uc_l, xmitq);
342}
343
344void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
345 struct tipc_link *rcv_l,
346 struct sk_buff_head *xmitq)
347{
348 u16 ack = snd_l->snd_nxt - 1;
349
350 snd_l->ackers--;
351 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
352 tipc_link_reset(rcv_l);
353 rcv_l->state = LINK_RESET;
354 if (!snd_l->ackers) {
355 tipc_link_reset(snd_l);
356 snd_l->state = LINK_RESET;
357 __skb_queue_purge(xmitq);
358 }
359}
360
361int tipc_link_bc_peers(struct tipc_link *l)
362{
363 return l->ackers;
364}
365
366void tipc_link_set_mtu(struct tipc_link *l, int mtu)
367{
368 l->mtu = mtu;
369}
370
371int tipc_link_mtu(struct tipc_link *l)
372{
373 return l->mtu;
374}
375
376u16 tipc_link_rcv_nxt(struct tipc_link *l)
377{
378 return l->rcv_nxt;
379}
380
381u16 tipc_link_acked(struct tipc_link *l)
382{
383 return l->acked;
384}
385
386char *tipc_link_name(struct tipc_link *l)
387{
388 return l->name;
389}
390
391/**
392 * tipc_link_create - create a new link
393 * @n: pointer to associated node
394 * @if_name: associated interface name
395 * @bearer_id: id (index) of associated bearer
396 * @tolerance: link tolerance to be used by link
397 * @net_plane: network plane (A,B,c..) this link belongs to
398 * @mtu: mtu to be advertised by link
399 * @priority: priority to be used by link
400 * @window: send window to be used by link
401 * @session: session to be used by link
402 * @ownnode: identity of own node
403 * @peer: node id of peer node
404 * @peer_caps: bitmap describing peer node capabilities
405 * @bc_sndlink: the namespace global link used for broadcast sending
406 * @bc_rcvlink: the peer specific link used for broadcast reception
407 * @inputq: queue to put messages ready for delivery
408 * @namedq: queue to put binding table update messages ready for delivery
409 * @link: return value, pointer to put the created link
410 *
411 * Returns true if link was created, otherwise false
412 */
413bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
414 int tolerance, char net_plane, u32 mtu, int priority,
415 int window, u32 session, u32 ownnode, u32 peer,
416 u16 peer_caps,
417 struct tipc_link *bc_sndlink,
418 struct tipc_link *bc_rcvlink,
419 struct sk_buff_head *inputq,
420 struct sk_buff_head *namedq,
421 struct tipc_link **link)
422{
423 struct tipc_link *l;
424
425 l = kzalloc(sizeof(*l), GFP_ATOMIC);
426 if (!l)
427 return false;
428 *link = l;
429 l->session = session;
430
431 /* Note: peer i/f name is completed by reset/activate message */
432 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
433 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
434 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
435 strcpy(l->if_name, if_name);
436 l->addr = peer;
437 l->peer_caps = peer_caps;
438 l->net = net;
439 l->peer_session = ANY_SESSION;
440 l->bearer_id = bearer_id;
441 l->tolerance = tolerance;
442 l->net_plane = net_plane;
443 l->advertised_mtu = mtu;
444 l->mtu = mtu;
445 l->priority = priority;
446 tipc_link_set_queue_limits(l, window);
447 l->ackers = 1;
448 l->bc_sndlink = bc_sndlink;
449 l->bc_rcvlink = bc_rcvlink;
450 l->inputq = inputq;
451 l->namedq = namedq;
452 l->state = LINK_RESETTING;
453 __skb_queue_head_init(&l->transmq);
454 __skb_queue_head_init(&l->backlogq);
455 __skb_queue_head_init(&l->deferdq);
456 skb_queue_head_init(&l->wakeupq);
457 skb_queue_head_init(l->inputq);
458 return true;
459}
460
461/**
462 * tipc_link_bc_create - create new link to be used for broadcast
463 * @n: pointer to associated node
464 * @mtu: mtu to be used
465 * @window: send window to be used
466 * @inputq: queue to put messages ready for delivery
467 * @namedq: queue to put binding table update messages ready for delivery
468 * @link: return value, pointer to put the created link
469 *
470 * Returns true if link was created, otherwise false
471 */
472bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
473 int mtu, int window, u16 peer_caps,
474 struct sk_buff_head *inputq,
475 struct sk_buff_head *namedq,
476 struct tipc_link *bc_sndlink,
477 struct tipc_link **link)
478{
479 struct tipc_link *l;
480
481 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
482 0, ownnode, peer, peer_caps, bc_sndlink,
483 NULL, inputq, namedq, link))
484 return false;
485
486 l = *link;
487 strcpy(l->name, tipc_bclink_name);
488 tipc_link_reset(l);
489 l->state = LINK_RESET;
490 l->ackers = 0;
491 l->bc_rcvlink = l;
492
493 /* Broadcast send link is always up */
494 if (link_is_bc_sndlink(l))
495 l->state = LINK_ESTABLISHED;
496
497 return true;
498}
499
500/**
501 * tipc_link_fsm_evt - link finite state machine
502 * @l: pointer to link
503 * @evt: state machine event to be processed
504 */
505int tipc_link_fsm_evt(struct tipc_link *l, int evt)
506{
507 int rc = 0;
508
509 switch (l->state) {
510 case LINK_RESETTING:
511 switch (evt) {
512 case LINK_PEER_RESET_EVT:
513 l->state = LINK_PEER_RESET;
514 break;
515 case LINK_RESET_EVT:
516 l->state = LINK_RESET;
517 break;
518 case LINK_FAILURE_EVT:
519 case LINK_FAILOVER_BEGIN_EVT:
520 case LINK_ESTABLISH_EVT:
521 case LINK_FAILOVER_END_EVT:
522 case LINK_SYNCH_BEGIN_EVT:
523 case LINK_SYNCH_END_EVT:
524 default:
525 goto illegal_evt;
526 }
527 break;
528 case LINK_RESET:
529 switch (evt) {
530 case LINK_PEER_RESET_EVT:
531 l->state = LINK_ESTABLISHING;
532 break;
533 case LINK_FAILOVER_BEGIN_EVT:
534 l->state = LINK_FAILINGOVER;
535 case LINK_FAILURE_EVT:
536 case LINK_RESET_EVT:
537 case LINK_ESTABLISH_EVT:
538 case LINK_FAILOVER_END_EVT:
539 break;
540 case LINK_SYNCH_BEGIN_EVT:
541 case LINK_SYNCH_END_EVT:
542 default:
543 goto illegal_evt;
544 }
545 break;
546 case LINK_PEER_RESET:
547 switch (evt) {
548 case LINK_RESET_EVT:
549 l->state = LINK_ESTABLISHING;
550 break;
551 case LINK_PEER_RESET_EVT:
552 case LINK_ESTABLISH_EVT:
553 case LINK_FAILURE_EVT:
554 break;
555 case LINK_SYNCH_BEGIN_EVT:
556 case LINK_SYNCH_END_EVT:
557 case LINK_FAILOVER_BEGIN_EVT:
558 case LINK_FAILOVER_END_EVT:
559 default:
560 goto illegal_evt;
561 }
562 break;
563 case LINK_FAILINGOVER:
564 switch (evt) {
565 case LINK_FAILOVER_END_EVT:
566 l->state = LINK_RESET;
567 break;
568 case LINK_PEER_RESET_EVT:
569 case LINK_RESET_EVT:
570 case LINK_ESTABLISH_EVT:
571 case LINK_FAILURE_EVT:
572 break;
573 case LINK_FAILOVER_BEGIN_EVT:
574 case LINK_SYNCH_BEGIN_EVT:
575 case LINK_SYNCH_END_EVT:
576 default:
577 goto illegal_evt;
578 }
579 break;
580 case LINK_ESTABLISHING:
581 switch (evt) {
582 case LINK_ESTABLISH_EVT:
583 l->state = LINK_ESTABLISHED;
584 break;
585 case LINK_FAILOVER_BEGIN_EVT:
586 l->state = LINK_FAILINGOVER;
587 break;
588 case LINK_RESET_EVT:
589 l->state = LINK_RESET;
590 break;
591 case LINK_FAILURE_EVT:
592 case LINK_PEER_RESET_EVT:
593 case LINK_SYNCH_BEGIN_EVT:
594 case LINK_FAILOVER_END_EVT:
595 break;
596 case LINK_SYNCH_END_EVT:
597 default:
598 goto illegal_evt;
599 }
600 break;
601 case LINK_ESTABLISHED:
602 switch (evt) {
603 case LINK_PEER_RESET_EVT:
604 l->state = LINK_PEER_RESET;
605 rc |= TIPC_LINK_DOWN_EVT;
606 break;
607 case LINK_FAILURE_EVT:
608 l->state = LINK_RESETTING;
609 rc |= TIPC_LINK_DOWN_EVT;
610 break;
611 case LINK_RESET_EVT:
612 l->state = LINK_RESET;
613 break;
614 case LINK_ESTABLISH_EVT:
615 case LINK_SYNCH_END_EVT:
616 break;
617 case LINK_SYNCH_BEGIN_EVT:
618 l->state = LINK_SYNCHING;
619 break;
620 case LINK_FAILOVER_BEGIN_EVT:
621 case LINK_FAILOVER_END_EVT:
622 default:
623 goto illegal_evt;
624 }
625 break;
626 case LINK_SYNCHING:
627 switch (evt) {
628 case LINK_PEER_RESET_EVT:
629 l->state = LINK_PEER_RESET;
630 rc |= TIPC_LINK_DOWN_EVT;
631 break;
632 case LINK_FAILURE_EVT:
633 l->state = LINK_RESETTING;
634 rc |= TIPC_LINK_DOWN_EVT;
635 break;
636 case LINK_RESET_EVT:
637 l->state = LINK_RESET;
638 break;
639 case LINK_ESTABLISH_EVT:
640 case LINK_SYNCH_BEGIN_EVT:
641 break;
642 case LINK_SYNCH_END_EVT:
643 l->state = LINK_ESTABLISHED;
644 break;
645 case LINK_FAILOVER_BEGIN_EVT:
646 case LINK_FAILOVER_END_EVT:
647 default:
648 goto illegal_evt;
649 }
650 break;
651 default:
652 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
653 }
654 return rc;
655illegal_evt:
656 pr_err("Illegal FSM event %x in state %x on link %s\n",
657 evt, l->state, l->name);
658 return rc;
659}
660
661/* link_profile_stats - update statistical profiling of traffic
662 */
663static void link_profile_stats(struct tipc_link *l)
664{
665 struct sk_buff *skb;
666 struct tipc_msg *msg;
667 int length;
668
669 /* Update counters used in statistical profiling of send traffic */
670 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
671 l->stats.queue_sz_counts++;
672
673 skb = skb_peek(&l->transmq);
674 if (!skb)
675 return;
676 msg = buf_msg(skb);
677 length = msg_size(msg);
678
679 if (msg_user(msg) == MSG_FRAGMENTER) {
680 if (msg_type(msg) != FIRST_FRAGMENT)
681 return;
682 length = msg_size(msg_get_wrapped(msg));
683 }
684 l->stats.msg_lengths_total += length;
685 l->stats.msg_length_counts++;
686 if (length <= 64)
687 l->stats.msg_length_profile[0]++;
688 else if (length <= 256)
689 l->stats.msg_length_profile[1]++;
690 else if (length <= 1024)
691 l->stats.msg_length_profile[2]++;
692 else if (length <= 4096)
693 l->stats.msg_length_profile[3]++;
694 else if (length <= 16384)
695 l->stats.msg_length_profile[4]++;
696 else if (length <= 32768)
697 l->stats.msg_length_profile[5]++;
698 else
699 l->stats.msg_length_profile[6]++;
700}
701
702/* tipc_link_timeout - perform periodic task as instructed from node timeout
703 */
704/* tipc_link_timeout - perform periodic task as instructed from node timeout
705 */
706int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
707{
708 int rc = 0;
709 int mtyp = STATE_MSG;
710 bool xmit = false;
711 bool prb = false;
712 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
713 u16 bc_acked = l->bc_rcvlink->acked;
714 bool bc_up = link_is_up(l->bc_rcvlink);
715
716 link_profile_stats(l);
717
718 switch (l->state) {
719 case LINK_ESTABLISHED:
720 case LINK_SYNCHING:
721 if (!l->silent_intv_cnt) {
722 if (bc_up && (bc_acked != bc_snt))
723 xmit = true;
724 } else if (l->silent_intv_cnt <= l->abort_limit) {
725 xmit = true;
726 prb = true;
727 } else {
728 rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
729 }
730 l->silent_intv_cnt++;
731 break;
732 case LINK_RESET:
733 xmit = true;
734 mtyp = RESET_MSG;
735 break;
736 case LINK_ESTABLISHING:
737 xmit = true;
738 mtyp = ACTIVATE_MSG;
739 break;
740 case LINK_PEER_RESET:
741 case LINK_RESETTING:
742 case LINK_FAILINGOVER:
743 break;
744 default:
745 break;
746 }
747
748 if (xmit)
749 tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq);
750
751 return rc;
752}
753
754/**
755 * link_schedule_user - schedule a message sender for wakeup after congestion
756 * @link: congested link
757 * @list: message that was attempted sent
758 * Create pseudo msg to send back to user when congestion abates
759 * Does not consume buffer list
760 */
761static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
762{
763 struct tipc_msg *msg = buf_msg(skb_peek(list));
764 int imp = msg_importance(msg);
765 u32 oport = msg_origport(msg);
766 u32 addr = tipc_own_addr(link->net);
767 struct sk_buff *skb;
768
769 /* This really cannot happen... */
770 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
771 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
772 return -ENOBUFS;
773 }
774 /* Non-blocking sender: */
775 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
776 return -ELINKCONG;
777
778 /* Create and schedule wakeup pseudo message */
779 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
780 addr, addr, oport, 0, 0);
781 if (!skb)
782 return -ENOBUFS;
783 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
784 TIPC_SKB_CB(skb)->chain_imp = imp;
785 skb_queue_tail(&link->wakeupq, skb);
786 link->stats.link_congs++;
787 return -ELINKCONG;
788}
789
790/**
791 * link_prepare_wakeup - prepare users for wakeup after congestion
792 * @link: congested link
793 * Move a number of waiting users, as permitted by available space in
794 * the send queue, from link wait queue to node wait queue for wakeup
795 */
796void link_prepare_wakeup(struct tipc_link *l)
797{
798 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
799 int imp, lim;
800 struct sk_buff *skb, *tmp;
801
802 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
803 imp = TIPC_SKB_CB(skb)->chain_imp;
804 lim = l->window + l->backlog[imp].limit;
805 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
806 if ((pnd[imp] + l->backlog[imp].len) >= lim)
807 break;
808 skb_unlink(skb, &l->wakeupq);
809 skb_queue_tail(l->inputq, skb);
810 }
811}
812
813void tipc_link_reset(struct tipc_link *l)
814{
815 l->peer_session = ANY_SESSION;
816 l->session++;
817 l->mtu = l->advertised_mtu;
818 __skb_queue_purge(&l->transmq);
819 __skb_queue_purge(&l->deferdq);
820 skb_queue_splice_init(&l->wakeupq, l->inputq);
821 __skb_queue_purge(&l->backlogq);
822 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
823 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
824 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
825 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
826 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
827 kfree_skb(l->reasm_buf);
828 kfree_skb(l->failover_reasm_skb);
829 l->reasm_buf = NULL;
830 l->failover_reasm_skb = NULL;
831 l->rcv_unacked = 0;
832 l->snd_nxt = 1;
833 l->rcv_nxt = 1;
834 l->acked = 0;
835 l->silent_intv_cnt = 0;
836 l->stats.recv_info = 0;
837 l->stale_count = 0;
838 l->bc_peer_is_up = false;
839 tipc_link_reset_stats(l);
840}
841
842/**
843 * tipc_link_xmit(): enqueue buffer list according to queue situation
844 * @link: link to use
845 * @list: chain of buffers containing message
846 * @xmitq: returned list of packets to be sent by caller
847 *
848 * Consumes the buffer chain, except when returning -ELINKCONG,
849 * since the caller then may want to make more send attempts.
850 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
851 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
852 */
853int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
854 struct sk_buff_head *xmitq)
855{
856 struct tipc_msg *hdr = buf_msg(skb_peek(list));
857 unsigned int maxwin = l->window;
858 unsigned int i, imp = msg_importance(hdr);
859 unsigned int mtu = l->mtu;
860 u16 ack = l->rcv_nxt - 1;
861 u16 seqno = l->snd_nxt;
862 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
863 struct sk_buff_head *transmq = &l->transmq;
864 struct sk_buff_head *backlogq = &l->backlogq;
865 struct sk_buff *skb, *_skb, *bskb;
866
867 /* Match msg importance against this and all higher backlog limits: */
868 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
869 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
870 return link_schedule_user(l, list);
871 }
872 if (unlikely(msg_size(hdr) > mtu)) {
873 skb_queue_purge(list);
874 return -EMSGSIZE;
875 }
876
877 /* Prepare each packet for sending, and add to relevant queue: */
878 while (skb_queue_len(list)) {
879 skb = skb_peek(list);
880 hdr = buf_msg(skb);
881 msg_set_seqno(hdr, seqno);
882 msg_set_ack(hdr, ack);
883 msg_set_bcast_ack(hdr, bc_ack);
884
885 if (likely(skb_queue_len(transmq) < maxwin)) {
886 _skb = skb_clone(skb, GFP_ATOMIC);
887 if (!_skb) {
888 skb_queue_purge(list);
889 return -ENOBUFS;
890 }
891 __skb_dequeue(list);
892 __skb_queue_tail(transmq, skb);
893 __skb_queue_tail(xmitq, _skb);
894 TIPC_SKB_CB(skb)->ackers = l->ackers;
895 l->rcv_unacked = 0;
896 seqno++;
897 continue;
898 }
899 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
900 kfree_skb(__skb_dequeue(list));
901 l->stats.sent_bundled++;
902 continue;
903 }
904 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
905 kfree_skb(__skb_dequeue(list));
906 __skb_queue_tail(backlogq, bskb);
907 l->backlog[msg_importance(buf_msg(bskb))].len++;
908 l->stats.sent_bundled++;
909 l->stats.sent_bundles++;
910 continue;
911 }
912 l->backlog[imp].len += skb_queue_len(list);
913 skb_queue_splice_tail_init(list, backlogq);
914 }
915 l->snd_nxt = seqno;
916 return 0;
917}
918
919void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
920{
921 struct sk_buff *skb, *_skb;
922 struct tipc_msg *hdr;
923 u16 seqno = l->snd_nxt;
924 u16 ack = l->rcv_nxt - 1;
925 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
926
927 while (skb_queue_len(&l->transmq) < l->window) {
928 skb = skb_peek(&l->backlogq);
929 if (!skb)
930 break;
931 _skb = skb_clone(skb, GFP_ATOMIC);
932 if (!_skb)
933 break;
934 __skb_dequeue(&l->backlogq);
935 hdr = buf_msg(skb);
936 l->backlog[msg_importance(hdr)].len--;
937 __skb_queue_tail(&l->transmq, skb);
938 __skb_queue_tail(xmitq, _skb);
939 TIPC_SKB_CB(skb)->ackers = l->ackers;
940 msg_set_seqno(hdr, seqno);
941 msg_set_ack(hdr, ack);
942 msg_set_bcast_ack(hdr, bc_ack);
943 l->rcv_unacked = 0;
944 seqno++;
945 }
946 l->snd_nxt = seqno;
947}
948
949static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
950{
951 struct tipc_msg *hdr = buf_msg(skb);
952
953 pr_warn("Retransmission failure on link <%s>\n", l->name);
954 link_print(l, "Resetting link ");
955 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
956 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
957 pr_info("sqno %u, prev: %x, src: %x\n",
958 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
959}
960
961int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
962 struct sk_buff_head *xmitq)
963{
964 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
965 struct tipc_msg *hdr;
966 u16 ack = l->rcv_nxt - 1;
967 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
968
969 if (!skb)
970 return 0;
971
972 /* Detect repeated retransmit failures on same packet */
973 if (likely(l->last_retransm != buf_seqno(skb))) {
974 l->last_retransm = buf_seqno(skb);
975 l->stale_count = 1;
976 } else if (++l->stale_count > 100) {
977 link_retransmit_failure(l, skb);
978 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
979 }
980
981 /* Move forward to where retransmission should start */
982 skb_queue_walk(&l->transmq, skb) {
983 if (!less(buf_seqno(skb), from))
984 break;
985 }
986
987 skb_queue_walk_from(&l->transmq, skb) {
988 if (more(buf_seqno(skb), to))
989 break;
990 hdr = buf_msg(skb);
991 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
992 if (!_skb)
993 return 0;
994 hdr = buf_msg(_skb);
995 msg_set_ack(hdr, ack);
996 msg_set_bcast_ack(hdr, bc_ack);
997 _skb->priority = TC_PRIO_CONTROL;
998 __skb_queue_tail(xmitq, _skb);
999 l->stats.retransmitted++;
1000 }
1001 return 0;
1002}
1003
1004/* tipc_data_input - deliver data and name distr msgs to upper layer
1005 *
1006 * Consumes buffer if message is of right type
1007 * Node lock must be held
1008 */
1009static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1010 struct sk_buff_head *inputq)
1011{
1012 switch (msg_user(buf_msg(skb))) {
1013 case TIPC_LOW_IMPORTANCE:
1014 case TIPC_MEDIUM_IMPORTANCE:
1015 case TIPC_HIGH_IMPORTANCE:
1016 case TIPC_CRITICAL_IMPORTANCE:
1017 case CONN_MANAGER:
1018 skb_queue_tail(inputq, skb);
1019 return true;
1020 case NAME_DISTRIBUTOR:
1021 l->bc_rcvlink->state = LINK_ESTABLISHED;
1022 skb_queue_tail(l->namedq, skb);
1023 return true;
1024 case MSG_BUNDLER:
1025 case TUNNEL_PROTOCOL:
1026 case MSG_FRAGMENTER:
1027 case BCAST_PROTOCOL:
1028 return false;
1029 default:
1030 pr_warn("Dropping received illegal msg type\n");
1031 kfree_skb(skb);
1032 return false;
1033 };
1034}
1035
1036/* tipc_link_input - process packet that has passed link protocol check
1037 *
1038 * Consumes buffer
1039 */
1040static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1041 struct sk_buff_head *inputq)
1042{
1043 struct tipc_msg *hdr = buf_msg(skb);
1044 struct sk_buff **reasm_skb = &l->reasm_buf;
1045 struct sk_buff *iskb;
1046 struct sk_buff_head tmpq;
1047 int usr = msg_user(hdr);
1048 int rc = 0;
1049 int pos = 0;
1050 int ipos = 0;
1051
1052 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1053 if (msg_type(hdr) == SYNCH_MSG) {
1054 __skb_queue_purge(&l->deferdq);
1055 goto drop;
1056 }
1057 if (!tipc_msg_extract(skb, &iskb, &ipos))
1058 return rc;
1059 kfree_skb(skb);
1060 skb = iskb;
1061 hdr = buf_msg(skb);
1062 if (less(msg_seqno(hdr), l->drop_point))
1063 goto drop;
1064 if (tipc_data_input(l, skb, inputq))
1065 return rc;
1066 usr = msg_user(hdr);
1067 reasm_skb = &l->failover_reasm_skb;
1068 }
1069
1070 if (usr == MSG_BUNDLER) {
1071 skb_queue_head_init(&tmpq);
1072 l->stats.recv_bundles++;
1073 l->stats.recv_bundled += msg_msgcnt(hdr);
1074 while (tipc_msg_extract(skb, &iskb, &pos))
1075 tipc_data_input(l, iskb, &tmpq);
1076 tipc_skb_queue_splice_tail(&tmpq, inputq);
1077 return 0;
1078 } else if (usr == MSG_FRAGMENTER) {
1079 l->stats.recv_fragments++;
1080 if (tipc_buf_append(reasm_skb, &skb)) {
1081 l->stats.recv_fragmented++;
1082 tipc_data_input(l, skb, inputq);
1083 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1084 pr_warn_ratelimited("Unable to build fragment list\n");
1085 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1086 }
1087 return 0;
1088 } else if (usr == BCAST_PROTOCOL) {
1089 tipc_bcast_lock(l->net);
1090 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1091 tipc_bcast_unlock(l->net);
1092 }
1093drop:
1094 kfree_skb(skb);
1095 return 0;
1096}
1097
1098static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1099{
1100 bool released = false;
1101 struct sk_buff *skb, *tmp;
1102
1103 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1104 if (more(buf_seqno(skb), acked))
1105 break;
1106 __skb_unlink(skb, &l->transmq);
1107 kfree_skb(skb);
1108 released = true;
1109 }
1110 return released;
1111}
1112
1113/* tipc_link_build_ack_msg: prepare link acknowledge message for transmission
1114 *
1115 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1116 * risk of ack storms towards the sender
1117 */
1118int tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1119{
1120 if (!l)
1121 return 0;
1122
1123 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1124 if (link_is_bc_rcvlink(l)) {
1125 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1126 return 0;
1127 l->rcv_unacked = 0;
1128 return TIPC_LINK_SND_BC_ACK;
1129 }
1130
1131 /* Unicast ACK */
1132 l->rcv_unacked = 0;
1133 l->stats.sent_acks++;
1134 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1135 return 0;
1136}
1137
1138/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1139 */
1140void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1141{
1142 int mtyp = RESET_MSG;
1143
1144 if (l->state == LINK_ESTABLISHING)
1145 mtyp = ACTIVATE_MSG;
1146
1147 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
1148}
1149
1150/* tipc_link_build_nack_msg: prepare link nack message for transmission
1151 */
1152static void tipc_link_build_nack_msg(struct tipc_link *l,
1153 struct sk_buff_head *xmitq)
1154{
1155 u32 def_cnt = ++l->stats.deferred_recv;
1156
1157 if (link_is_bc_rcvlink(l))
1158 return;
1159
1160 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1161 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1162}
1163
1164/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1165 * @l: the link that should handle the message
1166 * @skb: TIPC packet
1167 * @xmitq: queue to place packets to be sent after this call
1168 */
1169int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1170 struct sk_buff_head *xmitq)
1171{
1172 struct sk_buff_head *defq = &l->deferdq;
1173 struct tipc_msg *hdr;
1174 u16 seqno, rcv_nxt, win_lim;
1175 int rc = 0;
1176
1177 do {
1178 hdr = buf_msg(skb);
1179 seqno = msg_seqno(hdr);
1180 rcv_nxt = l->rcv_nxt;
1181 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1182
1183 /* Verify and update link state */
1184 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1185 return tipc_link_proto_rcv(l, skb, xmitq);
1186
1187 if (unlikely(!link_is_up(l))) {
1188 if (l->state == LINK_ESTABLISHING)
1189 rc = TIPC_LINK_UP_EVT;
1190 goto drop;
1191 }
1192
1193 /* Don't send probe at next timeout expiration */
1194 l->silent_intv_cnt = 0;
1195
1196 /* Drop if outside receive window */
1197 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1198 l->stats.duplicates++;
1199 goto drop;
1200 }
1201
1202 /* Forward queues and wake up waiting users */
1203 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1204 tipc_link_advance_backlog(l, xmitq);
1205 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1206 link_prepare_wakeup(l);
1207 }
1208
1209 /* Defer delivery if sequence gap */
1210 if (unlikely(seqno != rcv_nxt)) {
1211 __tipc_skb_queue_sorted(defq, seqno, skb);
1212 tipc_link_build_nack_msg(l, xmitq);
1213 break;
1214 }
1215
1216 /* Deliver packet */
1217 l->rcv_nxt++;
1218 l->stats.recv_info++;
1219 if (!tipc_data_input(l, skb, l->inputq))
1220 rc |= tipc_link_input(l, skb, l->inputq);
1221 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1222 rc |= tipc_link_build_ack_msg(l, xmitq);
1223 if (unlikely(rc & ~TIPC_LINK_SND_BC_ACK))
1224 break;
1225 } while ((skb = __skb_dequeue(defq)));
1226
1227 return rc;
1228drop:
1229 kfree_skb(skb);
1230 return rc;
1231}
1232
1233static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1234 u16 rcvgap, int tolerance, int priority,
1235 struct sk_buff_head *xmitq)
1236{
1237 struct sk_buff *skb;
1238 struct tipc_msg *hdr;
1239 struct sk_buff_head *dfq = &l->deferdq;
1240 bool node_up = link_is_up(l->bc_rcvlink);
1241
1242 /* Don't send protocol message during reset or link failover */
1243 if (tipc_link_is_blocked(l))
1244 return;
1245
1246 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1247 return;
1248
1249 if (!skb_queue_empty(dfq))
1250 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1251
1252 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1253 TIPC_MAX_IF_NAME, l->addr,
1254 tipc_own_addr(l->net), 0, 0, 0);
1255 if (!skb)
1256 return;
1257
1258 hdr = buf_msg(skb);
1259 msg_set_session(hdr, l->session);
1260 msg_set_bearer_id(hdr, l->bearer_id);
1261 msg_set_net_plane(hdr, l->net_plane);
1262 msg_set_next_sent(hdr, l->snd_nxt);
1263 msg_set_ack(hdr, l->rcv_nxt - 1);
1264 msg_set_bcast_ack(hdr, l->bc_rcvlink->rcv_nxt - 1);
1265 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1266 msg_set_link_tolerance(hdr, tolerance);
1267 msg_set_linkprio(hdr, priority);
1268 msg_set_redundant_link(hdr, node_up);
1269 msg_set_seq_gap(hdr, 0);
1270 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1271
1272 if (mtyp == STATE_MSG) {
1273 msg_set_seq_gap(hdr, rcvgap);
1274 msg_set_size(hdr, INT_H_SIZE);
1275 msg_set_probe(hdr, probe);
1276 l->stats.sent_states++;
1277 l->rcv_unacked = 0;
1278 } else {
1279 /* RESET_MSG or ACTIVATE_MSG */
1280 msg_set_max_pkt(hdr, l->advertised_mtu);
1281 strcpy(msg_data(hdr), l->if_name);
1282 }
1283 if (probe)
1284 l->stats.sent_probes++;
1285 if (rcvgap)
1286 l->stats.sent_nacks++;
1287 skb->priority = TC_PRIO_CONTROL;
1288 __skb_queue_tail(xmitq, skb);
1289}
1290
1291/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1292 * with contents of the link's transmit and backlog queues.
1293 */
1294void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1295 int mtyp, struct sk_buff_head *xmitq)
1296{
1297 struct sk_buff *skb, *tnlskb;
1298 struct tipc_msg *hdr, tnlhdr;
1299 struct sk_buff_head *queue = &l->transmq;
1300 struct sk_buff_head tmpxq, tnlq;
1301 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1302
1303 if (!tnl)
1304 return;
1305
1306 skb_queue_head_init(&tnlq);
1307 skb_queue_head_init(&tmpxq);
1308
1309 /* At least one packet required for safe algorithm => add dummy */
1310 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1311 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1312 0, 0, TIPC_ERR_NO_PORT);
1313 if (!skb) {
1314 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1315 return;
1316 }
1317 skb_queue_tail(&tnlq, skb);
1318 tipc_link_xmit(l, &tnlq, &tmpxq);
1319 __skb_queue_purge(&tmpxq);
1320
1321 /* Initialize reusable tunnel packet header */
1322 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1323 mtyp, INT_H_SIZE, l->addr);
1324 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1325 msg_set_msgcnt(&tnlhdr, pktcnt);
1326 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1327tnl:
1328 /* Wrap each packet into a tunnel packet */
1329 skb_queue_walk(queue, skb) {
1330 hdr = buf_msg(skb);
1331 if (queue == &l->backlogq)
1332 msg_set_seqno(hdr, seqno++);
1333 pktlen = msg_size(hdr);
1334 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1335 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE);
1336 if (!tnlskb) {
1337 pr_warn("%sunable to send packet\n", link_co_err);
1338 return;
1339 }
1340 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1341 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1342 __skb_queue_tail(&tnlq, tnlskb);
1343 }
1344 if (queue != &l->backlogq) {
1345 queue = &l->backlogq;
1346 goto tnl;
1347 }
1348
1349 tipc_link_xmit(tnl, &tnlq, xmitq);
1350
1351 if (mtyp == FAILOVER_MSG) {
1352 tnl->drop_point = l->rcv_nxt;
1353 tnl->failover_reasm_skb = l->reasm_buf;
1354 l->reasm_buf = NULL;
1355 }
1356}
1357
1358/* tipc_link_proto_rcv(): receive link level protocol message :
1359 * Note that network plane id propagates through the network, and may
1360 * change at any time. The node with lowest numerical id determines
1361 * network plane
1362 */
1363static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1364 struct sk_buff_head *xmitq)
1365{
1366 struct tipc_msg *hdr = buf_msg(skb);
1367 u16 rcvgap = 0;
1368 u16 ack = msg_ack(hdr);
1369 u16 gap = msg_seq_gap(hdr);
1370 u16 peers_snd_nxt = msg_next_sent(hdr);
1371 u16 peers_tol = msg_link_tolerance(hdr);
1372 u16 peers_prio = msg_linkprio(hdr);
1373 u16 rcv_nxt = l->rcv_nxt;
1374 int mtyp = msg_type(hdr);
1375 char *if_name;
1376 int rc = 0;
1377
1378 if (tipc_link_is_blocked(l) || !xmitq)
1379 goto exit;
1380
1381 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1382 l->net_plane = msg_net_plane(hdr);
1383
1384 switch (mtyp) {
1385 case RESET_MSG:
1386
1387 /* Ignore duplicate RESET with old session number */
1388 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1389 (l->peer_session != ANY_SESSION))
1390 break;
1391 /* fall thru' */
1392
1393 case ACTIVATE_MSG:
1394 skb_linearize(skb);
1395 hdr = buf_msg(skb);
1396
1397 /* Complete own link name with peer's interface name */
1398 if_name = strrchr(l->name, ':') + 1;
1399 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1400 break;
1401 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1402 break;
1403 strncpy(if_name, msg_data(hdr), TIPC_MAX_IF_NAME);
1404
1405 /* Update own tolerance if peer indicates a non-zero value */
1406 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1407 l->tolerance = peers_tol;
1408
1409 /* Update own priority if peer's priority is higher */
1410 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1411 l->priority = peers_prio;
1412
1413 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1414 if ((mtyp == RESET_MSG) || !link_is_up(l))
1415 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1416
1417 /* ACTIVATE_MSG takes up link if it was already locally reset */
1418 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1419 rc = TIPC_LINK_UP_EVT;
1420
1421 l->peer_session = msg_session(hdr);
1422 l->peer_bearer_id = msg_bearer_id(hdr);
1423 if (l->mtu > msg_max_pkt(hdr))
1424 l->mtu = msg_max_pkt(hdr);
1425 break;
1426
1427 case STATE_MSG:
1428
1429 /* Update own tolerance if peer indicates a non-zero value */
1430 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1431 l->tolerance = peers_tol;
1432
1433 if (peers_prio && in_range(peers_prio, TIPC_MIN_LINK_PRI,
1434 TIPC_MAX_LINK_PRI)) {
1435 l->priority = peers_prio;
1436 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1437 }
1438
1439 l->silent_intv_cnt = 0;
1440 l->stats.recv_states++;
1441 if (msg_probe(hdr))
1442 l->stats.recv_probes++;
1443
1444 if (!link_is_up(l)) {
1445 if (l->state == LINK_ESTABLISHING)
1446 rc = TIPC_LINK_UP_EVT;
1447 break;
1448 }
1449
1450 /* Send NACK if peer has sent pkts we haven't received yet */
1451 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1452 rcvgap = peers_snd_nxt - l->rcv_nxt;
1453 if (rcvgap || (msg_probe(hdr)))
1454 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1455 0, 0, xmitq);
1456 tipc_link_release_pkts(l, ack);
1457
1458 /* If NACK, retransmit will now start at right position */
1459 if (gap) {
1460 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1461 l->stats.recv_nacks++;
1462 }
1463
1464 tipc_link_advance_backlog(l, xmitq);
1465 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1466 link_prepare_wakeup(l);
1467 }
1468exit:
1469 kfree_skb(skb);
1470 return rc;
1471}
1472
1473/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1474 */
1475static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1476 u16 peers_snd_nxt,
1477 struct sk_buff_head *xmitq)
1478{
1479 struct sk_buff *skb;
1480 struct tipc_msg *hdr;
1481 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1482 u16 ack = l->rcv_nxt - 1;
1483 u16 gap_to = peers_snd_nxt - 1;
1484
1485 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1486 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
1487 if (!skb)
1488 return false;
1489 hdr = buf_msg(skb);
1490 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1491 msg_set_bcast_ack(hdr, ack);
1492 msg_set_bcgap_after(hdr, ack);
1493 if (dfrd_skb)
1494 gap_to = buf_seqno(dfrd_skb) - 1;
1495 msg_set_bcgap_to(hdr, gap_to);
1496 msg_set_non_seq(hdr, bcast);
1497 __skb_queue_tail(xmitq, skb);
1498 return true;
1499}
1500
1501/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1502 *
1503 * Give a newly added peer node the sequence number where it should
1504 * start receiving and acking broadcast packets.
1505 */
1506static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1507 struct sk_buff_head *xmitq)
1508{
1509 struct sk_buff_head list;
1510
1511 __skb_queue_head_init(&list);
1512 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1513 return;
1514 tipc_link_xmit(l, &list, xmitq);
1515}
1516
1517/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1518 */
1519void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1520{
1521 int mtyp = msg_type(hdr);
1522 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1523
1524 if (link_is_up(l))
1525 return;
1526
1527 if (msg_user(hdr) == BCAST_PROTOCOL) {
1528 l->rcv_nxt = peers_snd_nxt;
1529 l->state = LINK_ESTABLISHED;
1530 return;
1531 }
1532
1533 if (l->peer_caps & TIPC_BCAST_SYNCH)
1534 return;
1535
1536 if (msg_peer_node_is_up(hdr))
1537 return;
1538
1539 /* Compatibility: accept older, less safe initial synch data */
1540 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1541 l->rcv_nxt = peers_snd_nxt;
1542}
1543
1544/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1545 */
1546void tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1547 struct sk_buff_head *xmitq)
1548{
1549 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1550
1551 if (!link_is_up(l))
1552 return;
1553
1554 if (!msg_peer_node_is_up(hdr))
1555 return;
1556
1557 l->bc_peer_is_up = true;
1558
1559 /* Ignore if peers_snd_nxt goes beyond receive window */
1560 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1561 return;
1562
1563 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1564 l->nack_state = BC_NACK_SND_CONDITIONAL;
1565 return;
1566 }
1567
1568 /* Don't NACK if one was recently sent or peeked */
1569 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1570 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1571 return;
1572 }
1573
1574 /* Conditionally delay NACK sending until next synch rcv */
1575 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1576 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1577 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1578 return;
1579 }
1580
1581 /* Send NACK now but suppress next one */
1582 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1583 l->nack_state = BC_NACK_SND_SUPPRESS;
1584}
1585
1586void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1587 struct sk_buff_head *xmitq)
1588{
1589 struct sk_buff *skb, *tmp;
1590 struct tipc_link *snd_l = l->bc_sndlink;
1591
1592 if (!link_is_up(l) || !l->bc_peer_is_up)
1593 return;
1594
1595 if (!more(acked, l->acked))
1596 return;
1597
1598 /* Skip over packets peer has already acked */
1599 skb_queue_walk(&snd_l->transmq, skb) {
1600 if (more(buf_seqno(skb), l->acked))
1601 break;
1602 }
1603
1604 /* Update/release the packets peer is acking now */
1605 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1606 if (more(buf_seqno(skb), acked))
1607 break;
1608 if (!--TIPC_SKB_CB(skb)->ackers) {
1609 __skb_unlink(skb, &snd_l->transmq);
1610 kfree_skb(skb);
1611 }
1612 }
1613 l->acked = acked;
1614 tipc_link_advance_backlog(snd_l, xmitq);
1615 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1616 link_prepare_wakeup(snd_l);
1617}
1618
1619/* tipc_link_bc_nack_rcv(): receive broadcast nack message
1620 */
1621int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1622 struct sk_buff_head *xmitq)
1623{
1624 struct tipc_msg *hdr = buf_msg(skb);
1625 u32 dnode = msg_destnode(hdr);
1626 int mtyp = msg_type(hdr);
1627 u16 acked = msg_bcast_ack(hdr);
1628 u16 from = acked + 1;
1629 u16 to = msg_bcgap_to(hdr);
1630 u16 peers_snd_nxt = to + 1;
1631 int rc = 0;
1632
1633 kfree_skb(skb);
1634
1635 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1636 return 0;
1637
1638 if (mtyp != STATE_MSG)
1639 return 0;
1640
1641 if (dnode == tipc_own_addr(l->net)) {
1642 tipc_link_bc_ack_rcv(l, acked, xmitq);
1643 rc = tipc_link_retrans(l->bc_sndlink, from, to, xmitq);
1644 l->stats.recv_nacks++;
1645 return rc;
1646 }
1647
1648 /* Msg for other node => suppress own NACK at next sync if applicable */
1649 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1650 l->nack_state = BC_NACK_SND_SUPPRESS;
1651
1652 return 0;
1653}
1654
1655void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1656{
1657 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1658
1659 l->window = win;
1660 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1661 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1662 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1663 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1664 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1665}
1666
1667/**
1668 * link_reset_stats - reset link statistics
1669 * @l: pointer to link
1670 */
1671void tipc_link_reset_stats(struct tipc_link *l)
1672{
1673 memset(&l->stats, 0, sizeof(l->stats));
1674 if (!link_is_bc_sndlink(l)) {
1675 l->stats.sent_info = l->snd_nxt;
1676 l->stats.recv_info = l->rcv_nxt;
1677 }
1678}
1679
1680static void link_print(struct tipc_link *l, const char *str)
1681{
1682 struct sk_buff *hskb = skb_peek(&l->transmq);
1683 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1684 u16 tail = l->snd_nxt - 1;
1685
1686 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1687 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1688 skb_queue_len(&l->transmq), head, tail,
1689 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1690}
1691
1692/* Parse and validate nested (link) properties valid for media, bearer and link
1693 */
1694int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1695{
1696 int err;
1697
1698 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1699 tipc_nl_prop_policy);
1700 if (err)
1701 return err;
1702
1703 if (props[TIPC_NLA_PROP_PRIO]) {
1704 u32 prio;
1705
1706 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1707 if (prio > TIPC_MAX_LINK_PRI)
1708 return -EINVAL;
1709 }
1710
1711 if (props[TIPC_NLA_PROP_TOL]) {
1712 u32 tol;
1713
1714 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1715 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1716 return -EINVAL;
1717 }
1718
1719 if (props[TIPC_NLA_PROP_WIN]) {
1720 u32 win;
1721
1722 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1723 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1724 return -EINVAL;
1725 }
1726
1727 return 0;
1728}
1729
1730static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1731{
1732 int i;
1733 struct nlattr *stats;
1734
1735 struct nla_map {
1736 u32 key;
1737 u32 val;
1738 };
1739
1740 struct nla_map map[] = {
1741 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1742 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1743 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1744 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1745 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1746 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1747 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1748 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1749 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1750 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1751 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1752 s->msg_length_counts : 1},
1753 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1754 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1755 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1756 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1757 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1758 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1759 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1760 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1761 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1762 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1763 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1764 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1765 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1766 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1767 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1768 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1769 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1770 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1771 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1772 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1773 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1774 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1775 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1776 };
1777
1778 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1779 if (!stats)
1780 return -EMSGSIZE;
1781
1782 for (i = 0; i < ARRAY_SIZE(map); i++)
1783 if (nla_put_u32(skb, map[i].key, map[i].val))
1784 goto msg_full;
1785
1786 nla_nest_end(skb, stats);
1787
1788 return 0;
1789msg_full:
1790 nla_nest_cancel(skb, stats);
1791
1792 return -EMSGSIZE;
1793}
1794
1795/* Caller should hold appropriate locks to protect the link */
1796int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1797 struct tipc_link *link, int nlflags)
1798{
1799 int err;
1800 void *hdr;
1801 struct nlattr *attrs;
1802 struct nlattr *prop;
1803 struct tipc_net *tn = net_generic(net, tipc_net_id);
1804
1805 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1806 nlflags, TIPC_NL_LINK_GET);
1807 if (!hdr)
1808 return -EMSGSIZE;
1809
1810 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1811 if (!attrs)
1812 goto msg_full;
1813
1814 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1815 goto attr_msg_full;
1816 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1817 tipc_cluster_mask(tn->own_addr)))
1818 goto attr_msg_full;
1819 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1820 goto attr_msg_full;
1821 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
1822 goto attr_msg_full;
1823 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
1824 goto attr_msg_full;
1825
1826 if (tipc_link_is_up(link))
1827 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1828 goto attr_msg_full;
1829 if (link->active)
1830 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1831 goto attr_msg_full;
1832
1833 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1834 if (!prop)
1835 goto attr_msg_full;
1836 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1837 goto prop_msg_full;
1838 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1839 goto prop_msg_full;
1840 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1841 link->window))
1842 goto prop_msg_full;
1843 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1844 goto prop_msg_full;
1845 nla_nest_end(msg->skb, prop);
1846
1847 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1848 if (err)
1849 goto attr_msg_full;
1850
1851 nla_nest_end(msg->skb, attrs);
1852 genlmsg_end(msg->skb, hdr);
1853
1854 return 0;
1855
1856prop_msg_full:
1857 nla_nest_cancel(msg->skb, prop);
1858attr_msg_full:
1859 nla_nest_cancel(msg->skb, attrs);
1860msg_full:
1861 genlmsg_cancel(msg->skb, hdr);
1862
1863 return -EMSGSIZE;
1864}
1865
1866static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
1867 struct tipc_stats *stats)
1868{
1869 int i;
1870 struct nlattr *nest;
1871
1872 struct nla_map {
1873 __u32 key;
1874 __u32 val;
1875 };
1876
1877 struct nla_map map[] = {
1878 {TIPC_NLA_STATS_RX_INFO, stats->recv_info},
1879 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
1880 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
1881 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
1882 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
1883 {TIPC_NLA_STATS_TX_INFO, stats->sent_info},
1884 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
1885 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
1886 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
1887 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
1888 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
1889 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
1890 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
1891 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
1892 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
1893 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
1894 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
1895 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
1896 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
1897 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
1898 };
1899
1900 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1901 if (!nest)
1902 return -EMSGSIZE;
1903
1904 for (i = 0; i < ARRAY_SIZE(map); i++)
1905 if (nla_put_u32(skb, map[i].key, map[i].val))
1906 goto msg_full;
1907
1908 nla_nest_end(skb, nest);
1909
1910 return 0;
1911msg_full:
1912 nla_nest_cancel(skb, nest);
1913
1914 return -EMSGSIZE;
1915}
1916
1917int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
1918{
1919 int err;
1920 void *hdr;
1921 struct nlattr *attrs;
1922 struct nlattr *prop;
1923 struct tipc_net *tn = net_generic(net, tipc_net_id);
1924 struct tipc_link *bcl = tn->bcl;
1925
1926 if (!bcl)
1927 return 0;
1928
1929 tipc_bcast_lock(net);
1930
1931 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1932 NLM_F_MULTI, TIPC_NL_LINK_GET);
1933 if (!hdr) {
1934 tipc_bcast_unlock(net);
1935 return -EMSGSIZE;
1936 }
1937
1938 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1939 if (!attrs)
1940 goto msg_full;
1941
1942 /* The broadcast link is always up */
1943 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1944 goto attr_msg_full;
1945
1946 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
1947 goto attr_msg_full;
1948 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
1949 goto attr_msg_full;
1950 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, bcl->rcv_nxt))
1951 goto attr_msg_full;
1952 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, bcl->snd_nxt))
1953 goto attr_msg_full;
1954
1955 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1956 if (!prop)
1957 goto attr_msg_full;
1958 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
1959 goto prop_msg_full;
1960 nla_nest_end(msg->skb, prop);
1961
1962 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
1963 if (err)
1964 goto attr_msg_full;
1965
1966 tipc_bcast_unlock(net);
1967 nla_nest_end(msg->skb, attrs);
1968 genlmsg_end(msg->skb, hdr);
1969
1970 return 0;
1971
1972prop_msg_full:
1973 nla_nest_cancel(msg->skb, prop);
1974attr_msg_full:
1975 nla_nest_cancel(msg->skb, attrs);
1976msg_full:
1977 tipc_bcast_unlock(net);
1978 genlmsg_cancel(msg->skb, hdr);
1979
1980 return -EMSGSIZE;
1981}
1982
1983void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
1984 struct sk_buff_head *xmitq)
1985{
1986 l->tolerance = tol;
1987 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, tol, 0, xmitq);
1988}
1989
1990void tipc_link_set_prio(struct tipc_link *l, u32 prio,
1991 struct sk_buff_head *xmitq)
1992{
1993 l->priority = prio;
1994 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, prio, xmitq);
1995}
1996
1997void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
1998{
1999 l->abort_limit = limit;
2000}