1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* RxRPC packet transmission
3 *
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/net.h>
11 #include <linux/gfp.h>
12 #include <linux/skbuff.h>
13 #include <linux/export.h>
14 #include <net/sock.h>
15 #include <net/af_rxrpc.h>
16 #include "ar-internal.h"
17
18 struct rxrpc_ack_buffer {
19 struct rxrpc_wire_header whdr;
20 struct rxrpc_ackpacket ack;
21 u8 acks[255];
22 u8 pad[3];
23 struct rxrpc_ackinfo ackinfo;
24 };
25
26 struct rxrpc_abort_buffer {
27 struct rxrpc_wire_header whdr;
28 __be32 abort_code;
29 };
30
31 static const char rxrpc_keepalive_string[] = "";
32
33 /*
34 * Increase Tx backoff on transmission failure and clear it on success.
35 */
rxrpc_tx_backoff(struct rxrpc_call * call,int ret)36 static void rxrpc_tx_backoff(struct rxrpc_call *call, int ret)
37 {
38 if (ret < 0) {
39 u16 tx_backoff = READ_ONCE(call->tx_backoff);
40
41 if (tx_backoff < HZ)
42 WRITE_ONCE(call->tx_backoff, tx_backoff + 1);
43 } else {
44 WRITE_ONCE(call->tx_backoff, 0);
45 }
46 }
47
48 /*
49 * Arrange for a keepalive ping a certain time after we last transmitted. This
50 * lets the far side know we're still interested in this call and helps keep
51 * the route through any intervening firewall open.
52 *
53 * Receiving a response to the ping will prevent the ->expect_rx_by timer from
54 * expiring.
55 */
rxrpc_set_keepalive(struct rxrpc_call * call)56 static void rxrpc_set_keepalive(struct rxrpc_call *call)
57 {
58 unsigned long now = jiffies, keepalive_at = call->next_rx_timo / 6;
59
60 keepalive_at += now;
61 WRITE_ONCE(call->keepalive_at, keepalive_at);
62 rxrpc_reduce_call_timer(call, keepalive_at, now,
63 rxrpc_timer_set_for_keepalive);
64 }
65
66 /*
67 * Fill out an ACK packet.
68 */
rxrpc_fill_out_ack(struct rxrpc_connection * conn,struct rxrpc_call * call,struct rxrpc_ack_buffer * pkt,rxrpc_seq_t * _hard_ack,rxrpc_seq_t * _top,u8 reason)69 static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
70 struct rxrpc_call *call,
71 struct rxrpc_ack_buffer *pkt,
72 rxrpc_seq_t *_hard_ack,
73 rxrpc_seq_t *_top,
74 u8 reason)
75 {
76 rxrpc_serial_t serial;
77 unsigned int tmp;
78 rxrpc_seq_t hard_ack, top, seq;
79 int ix;
80 u32 mtu, jmax;
81 u8 *ackp = pkt->acks;
82
83 tmp = atomic_xchg(&call->ackr_nr_unacked, 0);
84 tmp |= atomic_xchg(&call->ackr_nr_consumed, 0);
85 if (!tmp && (reason == RXRPC_ACK_DELAY ||
86 reason == RXRPC_ACK_IDLE))
87 return 0;
88
89 /* Barrier against rxrpc_input_data(). */
90 serial = call->ackr_serial;
91 hard_ack = READ_ONCE(call->rx_hard_ack);
92 top = smp_load_acquire(&call->rx_top);
93 *_hard_ack = hard_ack;
94 *_top = top;
95
96 pkt->ack.bufferSpace = htons(8);
97 pkt->ack.maxSkew = htons(0);
98 pkt->ack.firstPacket = htonl(hard_ack + 1);
99 pkt->ack.previousPacket = htonl(call->ackr_highest_seq);
100 pkt->ack.serial = htonl(serial);
101 pkt->ack.reason = reason;
102 pkt->ack.nAcks = top - hard_ack;
103
104 if (reason == RXRPC_ACK_PING)
105 pkt->whdr.flags |= RXRPC_REQUEST_ACK;
106
107 if (after(top, hard_ack)) {
108 seq = hard_ack + 1;
109 do {
110 ix = seq & RXRPC_RXTX_BUFF_MASK;
111 if (call->rxtx_buffer[ix])
112 *ackp++ = RXRPC_ACK_TYPE_ACK;
113 else
114 *ackp++ = RXRPC_ACK_TYPE_NACK;
115 seq++;
116 } while (before_eq(seq, top));
117 }
118
119 mtu = conn->params.peer->if_mtu;
120 mtu -= conn->params.peer->hdrsize;
121 jmax = (call->nr_jumbo_bad > 3) ? 1 : rxrpc_rx_jumbo_max;
122 pkt->ackinfo.rxMTU = htonl(rxrpc_rx_mtu);
123 pkt->ackinfo.maxMTU = htonl(mtu);
124 pkt->ackinfo.rwind = htonl(call->rx_winsize);
125 pkt->ackinfo.jumbo_max = htonl(jmax);
126
127 *ackp++ = 0;
128 *ackp++ = 0;
129 *ackp++ = 0;
130 return top - hard_ack + 3;
131 }
132
133 /*
134 * Record the beginning of an RTT probe.
135 */
rxrpc_begin_rtt_probe(struct rxrpc_call * call,rxrpc_serial_t serial,enum rxrpc_rtt_tx_trace why)136 static int rxrpc_begin_rtt_probe(struct rxrpc_call *call, rxrpc_serial_t serial,
137 enum rxrpc_rtt_tx_trace why)
138 {
139 unsigned long avail = call->rtt_avail;
140 int rtt_slot = 9;
141
142 if (!(avail & RXRPC_CALL_RTT_AVAIL_MASK))
143 goto no_slot;
144
145 rtt_slot = __ffs(avail & RXRPC_CALL_RTT_AVAIL_MASK);
146 if (!test_and_clear_bit(rtt_slot, &call->rtt_avail))
147 goto no_slot;
148
149 call->rtt_serial[rtt_slot] = serial;
150 call->rtt_sent_at[rtt_slot] = ktime_get_real();
151 smp_wmb(); /* Write data before avail bit */
152 set_bit(rtt_slot + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail);
153
154 trace_rxrpc_rtt_tx(call, why, rtt_slot, serial);
155 return rtt_slot;
156
157 no_slot:
158 trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_no_slot, rtt_slot, serial);
159 return -1;
160 }
161
162 /*
163 * Cancel an RTT probe.
164 */
rxrpc_cancel_rtt_probe(struct rxrpc_call * call,rxrpc_serial_t serial,int rtt_slot)165 static void rxrpc_cancel_rtt_probe(struct rxrpc_call *call,
166 rxrpc_serial_t serial, int rtt_slot)
167 {
168 if (rtt_slot != -1) {
169 clear_bit(rtt_slot + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail);
170 smp_wmb(); /* Clear pending bit before setting slot */
171 set_bit(rtt_slot, &call->rtt_avail);
172 trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_cancel, rtt_slot, serial);
173 }
174 }
175
176 /*
177 * Send an ACK call packet.
178 */
rxrpc_send_ack_packet(struct rxrpc_call * call,bool ping,rxrpc_serial_t * _serial)179 int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
180 rxrpc_serial_t *_serial)
181 {
182 struct rxrpc_connection *conn;
183 struct rxrpc_ack_buffer *pkt;
184 struct msghdr msg;
185 struct kvec iov[2];
186 rxrpc_serial_t serial;
187 rxrpc_seq_t hard_ack, top;
188 size_t len, n;
189 int ret, rtt_slot = -1;
190 u8 reason;
191
192 if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
193 return -ECONNRESET;
194
195 pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
196 if (!pkt)
197 return -ENOMEM;
198
199 conn = call->conn;
200
201 msg.msg_name = &call->peer->srx.transport;
202 msg.msg_namelen = call->peer->srx.transport_len;
203 msg.msg_control = NULL;
204 msg.msg_controllen = 0;
205 msg.msg_flags = 0;
206
207 pkt->whdr.epoch = htonl(conn->proto.epoch);
208 pkt->whdr.cid = htonl(call->cid);
209 pkt->whdr.callNumber = htonl(call->call_id);
210 pkt->whdr.seq = 0;
211 pkt->whdr.type = RXRPC_PACKET_TYPE_ACK;
212 pkt->whdr.flags = RXRPC_SLOW_START_OK | conn->out_clientflag;
213 pkt->whdr.userStatus = 0;
214 pkt->whdr.securityIndex = call->security_ix;
215 pkt->whdr._rsvd = 0;
216 pkt->whdr.serviceId = htons(call->service_id);
217
218 spin_lock_bh(&call->lock);
219 if (ping) {
220 reason = RXRPC_ACK_PING;
221 } else {
222 reason = call->ackr_reason;
223 if (!call->ackr_reason) {
224 spin_unlock_bh(&call->lock);
225 ret = 0;
226 goto out;
227 }
228 call->ackr_reason = 0;
229 }
230 n = rxrpc_fill_out_ack(conn, call, pkt, &hard_ack, &top, reason);
231
232 spin_unlock_bh(&call->lock);
233 if (n == 0) {
234 kfree(pkt);
235 return 0;
236 }
237
238 iov[0].iov_base = pkt;
239 iov[0].iov_len = sizeof(pkt->whdr) + sizeof(pkt->ack) + n;
240 iov[1].iov_base = &pkt->ackinfo;
241 iov[1].iov_len = sizeof(pkt->ackinfo);
242 len = iov[0].iov_len + iov[1].iov_len;
243
244 serial = atomic_inc_return(&conn->serial);
245 pkt->whdr.serial = htonl(serial);
246 trace_rxrpc_tx_ack(call->debug_id, serial,
247 ntohl(pkt->ack.firstPacket),
248 ntohl(pkt->ack.serial),
249 pkt->ack.reason, pkt->ack.nAcks);
250 if (_serial)
251 *_serial = serial;
252
253 if (ping)
254 rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_ping);
255
256 ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
257 conn->params.peer->last_tx_at = ktime_get_seconds();
258 if (ret < 0)
259 trace_rxrpc_tx_fail(call->debug_id, serial, ret,
260 rxrpc_tx_point_call_ack);
261 else
262 trace_rxrpc_tx_packet(call->debug_id, &pkt->whdr,
263 rxrpc_tx_point_call_ack);
264 rxrpc_tx_backoff(call, ret);
265
266 if (call->state < RXRPC_CALL_COMPLETE) {
267 if (ret < 0) {
268 rxrpc_cancel_rtt_probe(call, serial, rtt_slot);
269 rxrpc_propose_ACK(call, pkt->ack.reason,
270 ntohl(pkt->ack.serial),
271 false, true,
272 rxrpc_propose_ack_retry_tx);
273 }
274
275 rxrpc_set_keepalive(call);
276 }
277
278 out:
279 kfree(pkt);
280 return ret;
281 }
282
283 /*
284 * Send an ABORT call packet.
285 */
rxrpc_send_abort_packet(struct rxrpc_call * call)286 int rxrpc_send_abort_packet(struct rxrpc_call *call)
287 {
288 struct rxrpc_connection *conn;
289 struct rxrpc_abort_buffer pkt;
290 struct msghdr msg;
291 struct kvec iov[1];
292 rxrpc_serial_t serial;
293 int ret;
294
295 /* Don't bother sending aborts for a client call once the server has
296 * hard-ACK'd all of its request data. After that point, we're not
297 * going to stop the operation proceeding, and whilst we might limit
298 * the reply, it's not worth it if we can send a new call on the same
299 * channel instead, thereby closing off this call.
300 */
301 if (rxrpc_is_client_call(call) &&
302 test_bit(RXRPC_CALL_TX_LAST, &call->flags))
303 return 0;
304
305 if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
306 return -ECONNRESET;
307
308 conn = call->conn;
309
310 msg.msg_name = &call->peer->srx.transport;
311 msg.msg_namelen = call->peer->srx.transport_len;
312 msg.msg_control = NULL;
313 msg.msg_controllen = 0;
314 msg.msg_flags = 0;
315
316 pkt.whdr.epoch = htonl(conn->proto.epoch);
317 pkt.whdr.cid = htonl(call->cid);
318 pkt.whdr.callNumber = htonl(call->call_id);
319 pkt.whdr.seq = 0;
320 pkt.whdr.type = RXRPC_PACKET_TYPE_ABORT;
321 pkt.whdr.flags = conn->out_clientflag;
322 pkt.whdr.userStatus = 0;
323 pkt.whdr.securityIndex = call->security_ix;
324 pkt.whdr._rsvd = 0;
325 pkt.whdr.serviceId = htons(call->service_id);
326 pkt.abort_code = htonl(call->abort_code);
327
328 iov[0].iov_base = &pkt;
329 iov[0].iov_len = sizeof(pkt);
330
331 serial = atomic_inc_return(&conn->serial);
332 pkt.whdr.serial = htonl(serial);
333
334 ret = kernel_sendmsg(conn->params.local->socket,
335 &msg, iov, 1, sizeof(pkt));
336 conn->params.peer->last_tx_at = ktime_get_seconds();
337 if (ret < 0)
338 trace_rxrpc_tx_fail(call->debug_id, serial, ret,
339 rxrpc_tx_point_call_abort);
340 else
341 trace_rxrpc_tx_packet(call->debug_id, &pkt.whdr,
342 rxrpc_tx_point_call_abort);
343 rxrpc_tx_backoff(call, ret);
344 return ret;
345 }
346
347 /*
348 * send a packet through the transport endpoint
349 */
rxrpc_send_data_packet(struct rxrpc_call * call,struct sk_buff * skb,bool retrans)350 int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
351 bool retrans)
352 {
353 struct rxrpc_connection *conn = call->conn;
354 struct rxrpc_wire_header whdr;
355 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
356 struct msghdr msg;
357 struct kvec iov[2];
358 rxrpc_serial_t serial;
359 size_t len;
360 int ret, rtt_slot = -1;
361
362 _enter(",{%d}", skb->len);
363
364 if (hlist_unhashed(&call->error_link)) {
365 spin_lock_bh(&call->peer->lock);
366 hlist_add_head_rcu(&call->error_link, &call->peer->error_targets);
367 spin_unlock_bh(&call->peer->lock);
368 }
369
370 /* Each transmission of a Tx packet needs a new serial number */
371 serial = atomic_inc_return(&conn->serial);
372
373 whdr.epoch = htonl(conn->proto.epoch);
374 whdr.cid = htonl(call->cid);
375 whdr.callNumber = htonl(call->call_id);
376 whdr.seq = htonl(sp->hdr.seq);
377 whdr.serial = htonl(serial);
378 whdr.type = RXRPC_PACKET_TYPE_DATA;
379 whdr.flags = sp->hdr.flags;
380 whdr.userStatus = 0;
381 whdr.securityIndex = call->security_ix;
382 whdr._rsvd = htons(sp->hdr._rsvd);
383 whdr.serviceId = htons(call->service_id);
384
385 if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) &&
386 sp->hdr.seq == 1)
387 whdr.userStatus = RXRPC_USERSTATUS_SERVICE_UPGRADE;
388
389 iov[0].iov_base = &whdr;
390 iov[0].iov_len = sizeof(whdr);
391 iov[1].iov_base = skb->head;
392 iov[1].iov_len = skb->len;
393 len = iov[0].iov_len + iov[1].iov_len;
394
395 msg.msg_name = &call->peer->srx.transport;
396 msg.msg_namelen = call->peer->srx.transport_len;
397 msg.msg_control = NULL;
398 msg.msg_controllen = 0;
399 msg.msg_flags = 0;
400
401 /* If our RTT cache needs working on, request an ACK. Also request
402 * ACKs if a DATA packet appears to have been lost.
403 *
404 * However, we mustn't request an ACK on the last reply packet of a
405 * service call, lest OpenAFS incorrectly send us an ACK with some
406 * soft-ACKs in it and then never follow up with a proper hard ACK.
407 */
408 if ((!(sp->hdr.flags & RXRPC_LAST_PACKET) ||
409 rxrpc_to_server(sp)
410 ) &&
411 (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events) ||
412 retrans ||
413 call->cong_mode == RXRPC_CALL_SLOW_START ||
414 (call->peer->rtt_count < 3 && sp->hdr.seq & 1) ||
415 ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000),
416 ktime_get_real())))
417 whdr.flags |= RXRPC_REQUEST_ACK;
418
419 if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
420 static int lose;
421 if ((lose++ & 7) == 7) {
422 ret = 0;
423 trace_rxrpc_tx_data(call, sp->hdr.seq, serial,
424 whdr.flags, retrans, true);
425 goto done;
426 }
427 }
428
429 trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags, retrans,
430 false);
431
432 /* send the packet with the don't fragment bit set if we currently
433 * think it's small enough */
434 if (iov[1].iov_len >= call->peer->maxdata)
435 goto send_fragmentable;
436
437 down_read(&conn->params.local->defrag_sem);
438
439 sp->hdr.serial = serial;
440 smp_wmb(); /* Set serial before timestamp */
441 skb->tstamp = ktime_get_real();
442 if (whdr.flags & RXRPC_REQUEST_ACK)
443 rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_data);
444
445 /* send the packet by UDP
446 * - returns -EMSGSIZE if UDP would have to fragment the packet
447 * to go out of the interface
448 * - in which case, we'll have processed the ICMP error
449 * message and update the peer record
450 */
451 ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
452 conn->params.peer->last_tx_at = ktime_get_seconds();
453
454 up_read(&conn->params.local->defrag_sem);
455 if (ret < 0) {
456 rxrpc_cancel_rtt_probe(call, serial, rtt_slot);
457 trace_rxrpc_tx_fail(call->debug_id, serial, ret,
458 rxrpc_tx_point_call_data_nofrag);
459 } else {
460 trace_rxrpc_tx_packet(call->debug_id, &whdr,
461 rxrpc_tx_point_call_data_nofrag);
462 }
463
464 rxrpc_tx_backoff(call, ret);
465 if (ret == -EMSGSIZE)
466 goto send_fragmentable;
467
468 done:
469 if (ret >= 0) {
470 if (whdr.flags & RXRPC_REQUEST_ACK) {
471 call->peer->rtt_last_req = skb->tstamp;
472 if (call->peer->rtt_count > 1) {
473 unsigned long nowj = jiffies, ack_lost_at;
474
475 ack_lost_at = rxrpc_get_rto_backoff(call->peer, false);
476 ack_lost_at += nowj;
477 WRITE_ONCE(call->ack_lost_at, ack_lost_at);
478 rxrpc_reduce_call_timer(call, ack_lost_at, nowj,
479 rxrpc_timer_set_for_lost_ack);
480 }
481 }
482
483 if (sp->hdr.seq == 1 &&
484 !test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER,
485 &call->flags)) {
486 unsigned long nowj = jiffies, expect_rx_by;
487
488 expect_rx_by = nowj + call->next_rx_timo;
489 WRITE_ONCE(call->expect_rx_by, expect_rx_by);
490 rxrpc_reduce_call_timer(call, expect_rx_by, nowj,
491 rxrpc_timer_set_for_normal);
492 }
493
494 rxrpc_set_keepalive(call);
495 } else {
496 /* Cancel the call if the initial transmission fails,
497 * particularly if that's due to network routing issues that
498 * aren't going away anytime soon. The layer above can arrange
499 * the retransmission.
500 */
501 if (!test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags))
502 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
503 RX_USER_ABORT, ret);
504 }
505
506 _leave(" = %d [%u]", ret, call->peer->maxdata);
507 return ret;
508
509 send_fragmentable:
510 /* attempt to send this message with fragmentation enabled */
511 _debug("send fragment");
512
513 down_write(&conn->params.local->defrag_sem);
514
515 sp->hdr.serial = serial;
516 smp_wmb(); /* Set serial before timestamp */
517 skb->tstamp = ktime_get_real();
518 if (whdr.flags & RXRPC_REQUEST_ACK)
519 rtt_slot = rxrpc_begin_rtt_probe(call, serial, rxrpc_rtt_tx_data);
520
521 switch (conn->params.local->srx.transport.family) {
522 case AF_INET6:
523 case AF_INET:
524 ip_sock_set_mtu_discover(conn->params.local->socket->sk,
525 IP_PMTUDISC_DONT);
526 ret = kernel_sendmsg(conn->params.local->socket, &msg,
527 iov, 2, len);
528 conn->params.peer->last_tx_at = ktime_get_seconds();
529
530 ip_sock_set_mtu_discover(conn->params.local->socket->sk,
531 IP_PMTUDISC_DO);
532 break;
533
534 default:
535 BUG();
536 }
537
538 if (ret < 0) {
539 rxrpc_cancel_rtt_probe(call, serial, rtt_slot);
540 trace_rxrpc_tx_fail(call->debug_id, serial, ret,
541 rxrpc_tx_point_call_data_frag);
542 } else {
543 trace_rxrpc_tx_packet(call->debug_id, &whdr,
544 rxrpc_tx_point_call_data_frag);
545 }
546 rxrpc_tx_backoff(call, ret);
547
548 up_write(&conn->params.local->defrag_sem);
549 goto done;
550 }
551
552 /*
553 * reject packets through the local endpoint
554 */
rxrpc_reject_packets(struct rxrpc_local * local)555 void rxrpc_reject_packets(struct rxrpc_local *local)
556 {
557 struct sockaddr_rxrpc srx;
558 struct rxrpc_skb_priv *sp;
559 struct rxrpc_wire_header whdr;
560 struct sk_buff *skb;
561 struct msghdr msg;
562 struct kvec iov[2];
563 size_t size;
564 __be32 code;
565 int ret, ioc;
566
567 _enter("%d", local->debug_id);
568
569 iov[0].iov_base = &whdr;
570 iov[0].iov_len = sizeof(whdr);
571 iov[1].iov_base = &code;
572 iov[1].iov_len = sizeof(code);
573
574 msg.msg_name = &srx.transport;
575 msg.msg_control = NULL;
576 msg.msg_controllen = 0;
577 msg.msg_flags = 0;
578
579 memset(&whdr, 0, sizeof(whdr));
580
581 while ((skb = skb_dequeue(&local->reject_queue))) {
582 rxrpc_see_skb(skb, rxrpc_skb_seen);
583 sp = rxrpc_skb(skb);
584
585 switch (skb->mark) {
586 case RXRPC_SKB_MARK_REJECT_BUSY:
587 whdr.type = RXRPC_PACKET_TYPE_BUSY;
588 size = sizeof(whdr);
589 ioc = 1;
590 break;
591 case RXRPC_SKB_MARK_REJECT_ABORT:
592 whdr.type = RXRPC_PACKET_TYPE_ABORT;
593 code = htonl(skb->priority);
594 size = sizeof(whdr) + sizeof(code);
595 ioc = 2;
596 break;
597 default:
598 rxrpc_free_skb(skb, rxrpc_skb_freed);
599 continue;
600 }
601
602 if (rxrpc_extract_addr_from_skb(&srx, skb) == 0) {
603 msg.msg_namelen = srx.transport_len;
604
605 whdr.epoch = htonl(sp->hdr.epoch);
606 whdr.cid = htonl(sp->hdr.cid);
607 whdr.callNumber = htonl(sp->hdr.callNumber);
608 whdr.serviceId = htons(sp->hdr.serviceId);
609 whdr.flags = sp->hdr.flags;
610 whdr.flags ^= RXRPC_CLIENT_INITIATED;
611 whdr.flags &= RXRPC_CLIENT_INITIATED;
612
613 ret = kernel_sendmsg(local->socket, &msg,
614 iov, ioc, size);
615 if (ret < 0)
616 trace_rxrpc_tx_fail(local->debug_id, 0, ret,
617 rxrpc_tx_point_reject);
618 else
619 trace_rxrpc_tx_packet(local->debug_id, &whdr,
620 rxrpc_tx_point_reject);
621 }
622
623 rxrpc_free_skb(skb, rxrpc_skb_freed);
624 }
625
626 _leave("");
627 }
628
629 /*
630 * Send a VERSION reply to a peer as a keepalive.
631 */
rxrpc_send_keepalive(struct rxrpc_peer * peer)632 void rxrpc_send_keepalive(struct rxrpc_peer *peer)
633 {
634 struct rxrpc_wire_header whdr;
635 struct msghdr msg;
636 struct kvec iov[2];
637 size_t len;
638 int ret;
639
640 _enter("");
641
642 msg.msg_name = &peer->srx.transport;
643 msg.msg_namelen = peer->srx.transport_len;
644 msg.msg_control = NULL;
645 msg.msg_controllen = 0;
646 msg.msg_flags = 0;
647
648 whdr.epoch = htonl(peer->local->rxnet->epoch);
649 whdr.cid = 0;
650 whdr.callNumber = 0;
651 whdr.seq = 0;
652 whdr.serial = 0;
653 whdr.type = RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */
654 whdr.flags = RXRPC_LAST_PACKET;
655 whdr.userStatus = 0;
656 whdr.securityIndex = 0;
657 whdr._rsvd = 0;
658 whdr.serviceId = 0;
659
660 iov[0].iov_base = &whdr;
661 iov[0].iov_len = sizeof(whdr);
662 iov[1].iov_base = (char *)rxrpc_keepalive_string;
663 iov[1].iov_len = sizeof(rxrpc_keepalive_string);
664
665 len = iov[0].iov_len + iov[1].iov_len;
666
667 _proto("Tx VERSION (keepalive)");
668
669 ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len);
670 if (ret < 0)
671 trace_rxrpc_tx_fail(peer->debug_id, 0, ret,
672 rxrpc_tx_point_version_keepalive);
673 else
674 trace_rxrpc_tx_packet(peer->debug_id, &whdr,
675 rxrpc_tx_point_version_keepalive);
676
677 peer->last_tx_at = ktime_get_seconds();
678 _leave("");
679 }
680
