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1// SPDX-License-Identifier: GPL-2.0-or-later
2/* AF_RXRPC sendmsg() implementation.
3 *
4 * Copyright (C) 2007, 2016 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 <linux/sched/signal.h>
15
16#include <net/sock.h>
17#include <net/af_rxrpc.h>
18#include "ar-internal.h"
19
20/*
21 * Propose an abort to be made in the I/O thread.
22 */
23bool rxrpc_propose_abort(struct rxrpc_call *call, s32 abort_code, int error,
24 enum rxrpc_abort_reason why)
25{
26 _enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
27
28 if (!call->send_abort && !rxrpc_call_is_complete(call)) {
29 call->send_abort_why = why;
30 call->send_abort_err = error;
31 call->send_abort_seq = 0;
32 /* Request abort locklessly vs rxrpc_input_call_event(). */
33 smp_store_release(&call->send_abort, abort_code);
34 rxrpc_poke_call(call, rxrpc_call_poke_abort);
35 return true;
36 }
37
38 return false;
39}
40
41/*
42 * Wait for a call to become connected. Interruption here doesn't cause the
43 * call to be aborted.
44 */
45static int rxrpc_wait_to_be_connected(struct rxrpc_call *call, long *timeo)
46{
47 DECLARE_WAITQUEUE(myself, current);
48 int ret = 0;
49
50 _enter("%d", call->debug_id);
51
52 if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN)
53 return call->error;
54
55 add_wait_queue_exclusive(&call->waitq, &myself);
56
57 for (;;) {
58 ret = call->error;
59 if (ret < 0)
60 break;
61
62 switch (call->interruptibility) {
63 case RXRPC_INTERRUPTIBLE:
64 case RXRPC_PREINTERRUPTIBLE:
65 set_current_state(TASK_INTERRUPTIBLE);
66 break;
67 case RXRPC_UNINTERRUPTIBLE:
68 default:
69 set_current_state(TASK_UNINTERRUPTIBLE);
70 break;
71 }
72 if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN) {
73 ret = call->error;
74 break;
75 }
76 if ((call->interruptibility == RXRPC_INTERRUPTIBLE ||
77 call->interruptibility == RXRPC_PREINTERRUPTIBLE) &&
78 signal_pending(current)) {
79 ret = sock_intr_errno(*timeo);
80 break;
81 }
82 *timeo = schedule_timeout(*timeo);
83 }
84
85 remove_wait_queue(&call->waitq, &myself);
86 __set_current_state(TASK_RUNNING);
87
88 if (ret == 0 && rxrpc_call_is_complete(call))
89 ret = call->error;
90
91 _leave(" = %d", ret);
92 return ret;
93}
94
95/*
96 * Return true if there's sufficient Tx queue space.
97 */
98static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
99{
100 if (_tx_win)
101 *_tx_win = call->tx_bottom;
102 return call->tx_prepared - call->tx_bottom < 256;
103}
104
105/*
106 * Wait for space to appear in the Tx queue or a signal to occur.
107 */
108static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
109 struct rxrpc_call *call,
110 long *timeo)
111{
112 for (;;) {
113 set_current_state(TASK_INTERRUPTIBLE);
114 if (rxrpc_check_tx_space(call, NULL))
115 return 0;
116
117 if (rxrpc_call_is_complete(call))
118 return call->error;
119
120 if (signal_pending(current))
121 return sock_intr_errno(*timeo);
122
123 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
124 *timeo = schedule_timeout(*timeo);
125 }
126}
127
128/*
129 * Wait for space to appear in the Tx queue uninterruptibly, but with
130 * a timeout of 2*RTT if no progress was made and a signal occurred.
131 */
132static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
133 struct rxrpc_call *call)
134{
135 rxrpc_seq_t tx_start, tx_win;
136 signed long rtt, timeout;
137
138 rtt = READ_ONCE(call->peer->srtt_us) >> 3;
139 rtt = usecs_to_jiffies(rtt) * 2;
140 if (rtt < 2)
141 rtt = 2;
142
143 timeout = rtt;
144 tx_start = smp_load_acquire(&call->acks_hard_ack);
145
146 for (;;) {
147 set_current_state(TASK_UNINTERRUPTIBLE);
148
149 if (rxrpc_check_tx_space(call, &tx_win))
150 return 0;
151
152 if (rxrpc_call_is_complete(call))
153 return call->error;
154
155 if (timeout == 0 &&
156 tx_win == tx_start && signal_pending(current))
157 return -EINTR;
158
159 if (tx_win != tx_start) {
160 timeout = rtt;
161 tx_start = tx_win;
162 }
163
164 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
165 timeout = schedule_timeout(timeout);
166 }
167}
168
169/*
170 * Wait for space to appear in the Tx queue uninterruptibly.
171 */
172static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
173 struct rxrpc_call *call,
174 long *timeo)
175{
176 for (;;) {
177 set_current_state(TASK_UNINTERRUPTIBLE);
178 if (rxrpc_check_tx_space(call, NULL))
179 return 0;
180
181 if (rxrpc_call_is_complete(call))
182 return call->error;
183
184 trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
185 *timeo = schedule_timeout(*timeo);
186 }
187}
188
189/*
190 * wait for space to appear in the transmit/ACK window
191 * - caller holds the socket locked
192 */
193static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
194 struct rxrpc_call *call,
195 long *timeo,
196 bool waitall)
197{
198 DECLARE_WAITQUEUE(myself, current);
199 int ret;
200
201 _enter(",{%u,%u,%u,%u}",
202 call->tx_bottom, call->acks_hard_ack, call->tx_top, call->tx_winsize);
203
204 add_wait_queue(&call->waitq, &myself);
205
206 switch (call->interruptibility) {
207 case RXRPC_INTERRUPTIBLE:
208 if (waitall)
209 ret = rxrpc_wait_for_tx_window_waitall(rx, call);
210 else
211 ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
212 break;
213 case RXRPC_PREINTERRUPTIBLE:
214 case RXRPC_UNINTERRUPTIBLE:
215 default:
216 ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
217 break;
218 }
219
220 remove_wait_queue(&call->waitq, &myself);
221 set_current_state(TASK_RUNNING);
222 _leave(" = %d", ret);
223 return ret;
224}
225
226/*
227 * Notify the owner of the call that the transmit phase is ended and the last
228 * packet has been queued.
229 */
230static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
231 rxrpc_notify_end_tx_t notify_end_tx)
232{
233 if (notify_end_tx)
234 notify_end_tx(&rx->sk, call, call->user_call_ID);
235}
236
237/*
238 * Queue a DATA packet for transmission, set the resend timeout and send
239 * the packet immediately. Returns the error from rxrpc_send_data_packet()
240 * in case the caller wants to do something with it.
241 */
242static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
243 struct rxrpc_txbuf *txb,
244 rxrpc_notify_end_tx_t notify_end_tx)
245{
246 rxrpc_seq_t seq = txb->seq;
247 bool last = test_bit(RXRPC_TXBUF_LAST, &txb->flags), poke;
248
249 rxrpc_inc_stat(call->rxnet, stat_tx_data);
250
251 ASSERTCMP(txb->seq, ==, call->tx_prepared + 1);
252
253 /* We have to set the timestamp before queueing as the retransmit
254 * algorithm can see the packet as soon as we queue it.
255 */
256 txb->last_sent = ktime_get_real();
257
258 if (last)
259 trace_rxrpc_txqueue(call, rxrpc_txqueue_queue_last);
260 else
261 trace_rxrpc_txqueue(call, rxrpc_txqueue_queue);
262
263 /* Add the packet to the call's output buffer */
264 spin_lock(&call->tx_lock);
265 poke = list_empty(&call->tx_sendmsg);
266 list_add_tail(&txb->call_link, &call->tx_sendmsg);
267 call->tx_prepared = seq;
268 if (last)
269 rxrpc_notify_end_tx(rx, call, notify_end_tx);
270 spin_unlock(&call->tx_lock);
271
272 if (poke)
273 rxrpc_poke_call(call, rxrpc_call_poke_start);
274}
275
276/*
277 * send data through a socket
278 * - must be called in process context
279 * - The caller holds the call user access mutex, but not the socket lock.
280 */
281static int rxrpc_send_data(struct rxrpc_sock *rx,
282 struct rxrpc_call *call,
283 struct msghdr *msg, size_t len,
284 rxrpc_notify_end_tx_t notify_end_tx,
285 bool *_dropped_lock)
286{
287 struct rxrpc_txbuf *txb;
288 struct sock *sk = &rx->sk;
289 enum rxrpc_call_state state;
290 long timeo;
291 bool more = msg->msg_flags & MSG_MORE;
292 int ret, copied = 0;
293
294 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
295
296 ret = rxrpc_wait_to_be_connected(call, &timeo);
297 if (ret < 0)
298 return ret;
299
300 if (call->conn->state == RXRPC_CONN_CLIENT_UNSECURED) {
301 ret = rxrpc_init_client_conn_security(call->conn);
302 if (ret < 0)
303 return ret;
304 }
305
306 /* this should be in poll */
307 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
308
309reload:
310 ret = -EPIPE;
311 if (sk->sk_shutdown & SEND_SHUTDOWN)
312 goto maybe_error;
313 state = rxrpc_call_state(call);
314 ret = -ESHUTDOWN;
315 if (state >= RXRPC_CALL_COMPLETE)
316 goto maybe_error;
317 ret = -EPROTO;
318 if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
319 state != RXRPC_CALL_SERVER_ACK_REQUEST &&
320 state != RXRPC_CALL_SERVER_SEND_REPLY) {
321 /* Request phase complete for this client call */
322 trace_rxrpc_abort(call->debug_id, rxrpc_sendmsg_late_send,
323 call->cid, call->call_id, call->rx_consumed,
324 0, -EPROTO);
325 goto maybe_error;
326 }
327
328 ret = -EMSGSIZE;
329 if (call->tx_total_len != -1) {
330 if (len - copied > call->tx_total_len)
331 goto maybe_error;
332 if (!more && len - copied != call->tx_total_len)
333 goto maybe_error;
334 }
335
336 txb = call->tx_pending;
337 call->tx_pending = NULL;
338 if (txb)
339 rxrpc_see_txbuf(txb, rxrpc_txbuf_see_send_more);
340
341 do {
342 if (!txb) {
343 size_t remain, bufsize, chunk, offset;
344
345 _debug("alloc");
346
347 if (!rxrpc_check_tx_space(call, NULL))
348 goto wait_for_space;
349
350 /* Work out the maximum size of a packet. Assume that
351 * the security header is going to be in the padded
352 * region (enc blocksize), but the trailer is not.
353 */
354 remain = more ? INT_MAX : msg_data_left(msg);
355 ret = call->conn->security->how_much_data(call, remain,
356 &bufsize, &chunk, &offset);
357 if (ret < 0)
358 goto maybe_error;
359
360 _debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
361
362 /* create a buffer that we can retain until it's ACK'd */
363 ret = -ENOMEM;
364 txb = rxrpc_alloc_txbuf(call, RXRPC_PACKET_TYPE_DATA,
365 GFP_KERNEL);
366 if (!txb)
367 goto maybe_error;
368
369 txb->offset = offset;
370 txb->space -= offset;
371 txb->space = min_t(size_t, chunk, txb->space);
372 }
373
374 _debug("append");
375
376 /* append next segment of data to the current buffer */
377 if (msg_data_left(msg) > 0) {
378 size_t copy = min_t(size_t, txb->space, msg_data_left(msg));
379
380 _debug("add %zu", copy);
381 if (!copy_from_iter_full(txb->data + txb->offset, copy,
382 &msg->msg_iter))
383 goto efault;
384 _debug("added");
385 txb->space -= copy;
386 txb->len += copy;
387 txb->offset += copy;
388 copied += copy;
389 if (call->tx_total_len != -1)
390 call->tx_total_len -= copy;
391 }
392
393 /* check for the far side aborting the call or a network error
394 * occurring */
395 if (rxrpc_call_is_complete(call))
396 goto call_terminated;
397
398 /* add the packet to the send queue if it's now full */
399 if (!txb->space ||
400 (msg_data_left(msg) == 0 && !more)) {
401 if (msg_data_left(msg) == 0 && !more) {
402 txb->wire.flags |= RXRPC_LAST_PACKET;
403 __set_bit(RXRPC_TXBUF_LAST, &txb->flags);
404 }
405 else if (call->tx_top - call->acks_hard_ack <
406 call->tx_winsize)
407 txb->wire.flags |= RXRPC_MORE_PACKETS;
408
409 ret = call->security->secure_packet(call, txb);
410 if (ret < 0)
411 goto out;
412
413 rxrpc_queue_packet(rx, call, txb, notify_end_tx);
414 txb = NULL;
415 }
416 } while (msg_data_left(msg) > 0);
417
418success:
419 ret = copied;
420 if (rxrpc_call_is_complete(call) &&
421 call->error < 0)
422 ret = call->error;
423out:
424 call->tx_pending = txb;
425 _leave(" = %d", ret);
426 return ret;
427
428call_terminated:
429 rxrpc_put_txbuf(txb, rxrpc_txbuf_put_send_aborted);
430 _leave(" = %d", call->error);
431 return call->error;
432
433maybe_error:
434 if (copied)
435 goto success;
436 goto out;
437
438efault:
439 ret = -EFAULT;
440 goto out;
441
442wait_for_space:
443 ret = -EAGAIN;
444 if (msg->msg_flags & MSG_DONTWAIT)
445 goto maybe_error;
446 mutex_unlock(&call->user_mutex);
447 *_dropped_lock = true;
448 ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
449 msg->msg_flags & MSG_WAITALL);
450 if (ret < 0)
451 goto maybe_error;
452 if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
453 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
454 ret = sock_intr_errno(timeo);
455 goto maybe_error;
456 }
457 } else {
458 mutex_lock(&call->user_mutex);
459 }
460 *_dropped_lock = false;
461 goto reload;
462}
463
464/*
465 * extract control messages from the sendmsg() control buffer
466 */
467static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
468{
469 struct cmsghdr *cmsg;
470 bool got_user_ID = false;
471 int len;
472
473 if (msg->msg_controllen == 0)
474 return -EINVAL;
475
476 for_each_cmsghdr(cmsg, msg) {
477 if (!CMSG_OK(msg, cmsg))
478 return -EINVAL;
479
480 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
481 _debug("CMSG %d, %d, %d",
482 cmsg->cmsg_level, cmsg->cmsg_type, len);
483
484 if (cmsg->cmsg_level != SOL_RXRPC)
485 continue;
486
487 switch (cmsg->cmsg_type) {
488 case RXRPC_USER_CALL_ID:
489 if (msg->msg_flags & MSG_CMSG_COMPAT) {
490 if (len != sizeof(u32))
491 return -EINVAL;
492 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
493 } else {
494 if (len != sizeof(unsigned long))
495 return -EINVAL;
496 p->call.user_call_ID = *(unsigned long *)
497 CMSG_DATA(cmsg);
498 }
499 got_user_ID = true;
500 break;
501
502 case RXRPC_ABORT:
503 if (p->command != RXRPC_CMD_SEND_DATA)
504 return -EINVAL;
505 p->command = RXRPC_CMD_SEND_ABORT;
506 if (len != sizeof(p->abort_code))
507 return -EINVAL;
508 p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
509 if (p->abort_code == 0)
510 return -EINVAL;
511 break;
512
513 case RXRPC_CHARGE_ACCEPT:
514 if (p->command != RXRPC_CMD_SEND_DATA)
515 return -EINVAL;
516 p->command = RXRPC_CMD_CHARGE_ACCEPT;
517 if (len != 0)
518 return -EINVAL;
519 break;
520
521 case RXRPC_EXCLUSIVE_CALL:
522 p->exclusive = true;
523 if (len != 0)
524 return -EINVAL;
525 break;
526
527 case RXRPC_UPGRADE_SERVICE:
528 p->upgrade = true;
529 if (len != 0)
530 return -EINVAL;
531 break;
532
533 case RXRPC_TX_LENGTH:
534 if (p->call.tx_total_len != -1 || len != sizeof(__s64))
535 return -EINVAL;
536 p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
537 if (p->call.tx_total_len < 0)
538 return -EINVAL;
539 break;
540
541 case RXRPC_SET_CALL_TIMEOUT:
542 if (len & 3 || len < 4 || len > 12)
543 return -EINVAL;
544 memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
545 p->call.nr_timeouts = len / 4;
546 if (p->call.timeouts.hard > INT_MAX / HZ)
547 return -ERANGE;
548 if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
549 return -ERANGE;
550 if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
551 return -ERANGE;
552 break;
553
554 default:
555 return -EINVAL;
556 }
557 }
558
559 if (!got_user_ID)
560 return -EINVAL;
561 if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
562 return -EINVAL;
563 _leave(" = 0");
564 return 0;
565}
566
567/*
568 * Create a new client call for sendmsg().
569 * - Called with the socket lock held, which it must release.
570 * - If it returns a call, the call's lock will need releasing by the caller.
571 */
572static struct rxrpc_call *
573rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
574 struct rxrpc_send_params *p)
575 __releases(&rx->sk.sk_lock.slock)
576 __acquires(&call->user_mutex)
577{
578 struct rxrpc_conn_parameters cp;
579 struct rxrpc_call *call;
580 struct key *key;
581
582 DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
583
584 _enter("");
585
586 if (!msg->msg_name) {
587 release_sock(&rx->sk);
588 return ERR_PTR(-EDESTADDRREQ);
589 }
590
591 key = rx->key;
592 if (key && !rx->key->payload.data[0])
593 key = NULL;
594
595 memset(&cp, 0, sizeof(cp));
596 cp.local = rx->local;
597 cp.key = rx->key;
598 cp.security_level = rx->min_sec_level;
599 cp.exclusive = rx->exclusive | p->exclusive;
600 cp.upgrade = p->upgrade;
601 cp.service_id = srx->srx_service;
602 call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
603 atomic_inc_return(&rxrpc_debug_id));
604 /* The socket is now unlocked */
605
606 _leave(" = %p\n", call);
607 return call;
608}
609
610/*
611 * send a message forming part of a client call through an RxRPC socket
612 * - caller holds the socket locked
613 * - the socket may be either a client socket or a server socket
614 */
615int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
616 __releases(&rx->sk.sk_lock.slock)
617{
618 struct rxrpc_call *call;
619 unsigned long now, j;
620 bool dropped_lock = false;
621 int ret;
622
623 struct rxrpc_send_params p = {
624 .call.tx_total_len = -1,
625 .call.user_call_ID = 0,
626 .call.nr_timeouts = 0,
627 .call.interruptibility = RXRPC_INTERRUPTIBLE,
628 .abort_code = 0,
629 .command = RXRPC_CMD_SEND_DATA,
630 .exclusive = false,
631 .upgrade = false,
632 };
633
634 _enter("");
635
636 ret = rxrpc_sendmsg_cmsg(msg, &p);
637 if (ret < 0)
638 goto error_release_sock;
639
640 if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
641 ret = -EINVAL;
642 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
643 goto error_release_sock;
644 ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
645 goto error_release_sock;
646 }
647
648 call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
649 if (!call) {
650 ret = -EBADSLT;
651 if (p.command != RXRPC_CMD_SEND_DATA)
652 goto error_release_sock;
653 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
654 /* The socket is now unlocked... */
655 if (IS_ERR(call))
656 return PTR_ERR(call);
657 /* ... and we have the call lock. */
658 ret = 0;
659 if (rxrpc_call_is_complete(call))
660 goto out_put_unlock;
661 } else {
662 switch (rxrpc_call_state(call)) {
663 case RXRPC_CALL_UNINITIALISED:
664 case RXRPC_CALL_CLIENT_AWAIT_CONN:
665 case RXRPC_CALL_SERVER_PREALLOC:
666 case RXRPC_CALL_SERVER_SECURING:
667 rxrpc_put_call(call, rxrpc_call_put_sendmsg);
668 ret = -EBUSY;
669 goto error_release_sock;
670 default:
671 break;
672 }
673
674 ret = mutex_lock_interruptible(&call->user_mutex);
675 release_sock(&rx->sk);
676 if (ret < 0) {
677 ret = -ERESTARTSYS;
678 goto error_put;
679 }
680
681 if (p.call.tx_total_len != -1) {
682 ret = -EINVAL;
683 if (call->tx_total_len != -1 ||
684 call->tx_pending ||
685 call->tx_top != 0)
686 goto out_put_unlock;
687 call->tx_total_len = p.call.tx_total_len;
688 }
689 }
690
691 switch (p.call.nr_timeouts) {
692 case 3:
693 j = msecs_to_jiffies(p.call.timeouts.normal);
694 if (p.call.timeouts.normal > 0 && j == 0)
695 j = 1;
696 WRITE_ONCE(call->next_rx_timo, j);
697 fallthrough;
698 case 2:
699 j = msecs_to_jiffies(p.call.timeouts.idle);
700 if (p.call.timeouts.idle > 0 && j == 0)
701 j = 1;
702 WRITE_ONCE(call->next_req_timo, j);
703 fallthrough;
704 case 1:
705 if (p.call.timeouts.hard > 0) {
706 j = msecs_to_jiffies(p.call.timeouts.hard);
707 now = jiffies;
708 j += now;
709 WRITE_ONCE(call->expect_term_by, j);
710 rxrpc_reduce_call_timer(call, j, now,
711 rxrpc_timer_set_for_hard);
712 }
713 break;
714 }
715
716 if (rxrpc_call_is_complete(call)) {
717 /* it's too late for this call */
718 ret = -ESHUTDOWN;
719 } else if (p.command == RXRPC_CMD_SEND_ABORT) {
720 rxrpc_propose_abort(call, p.abort_code, -ECONNABORTED,
721 rxrpc_abort_call_sendmsg);
722 ret = 0;
723 } else if (p.command != RXRPC_CMD_SEND_DATA) {
724 ret = -EINVAL;
725 } else {
726 ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
727 }
728
729out_put_unlock:
730 if (!dropped_lock)
731 mutex_unlock(&call->user_mutex);
732error_put:
733 rxrpc_put_call(call, rxrpc_call_put_sendmsg);
734 _leave(" = %d", ret);
735 return ret;
736
737error_release_sock:
738 release_sock(&rx->sk);
739 return ret;
740}
741
742/**
743 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
744 * @sock: The socket the call is on
745 * @call: The call to send data through
746 * @msg: The data to send
747 * @len: The amount of data to send
748 * @notify_end_tx: Notification that the last packet is queued.
749 *
750 * Allow a kernel service to send data on a call. The call must be in an state
751 * appropriate to sending data. No control data should be supplied in @msg,
752 * nor should an address be supplied. MSG_MORE should be flagged if there's
753 * more data to come, otherwise this data will end the transmission phase.
754 */
755int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
756 struct msghdr *msg, size_t len,
757 rxrpc_notify_end_tx_t notify_end_tx)
758{
759 bool dropped_lock = false;
760 int ret;
761
762 _enter("{%d},", call->debug_id);
763
764 ASSERTCMP(msg->msg_name, ==, NULL);
765 ASSERTCMP(msg->msg_control, ==, NULL);
766
767 mutex_lock(&call->user_mutex);
768
769 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
770 notify_end_tx, &dropped_lock);
771 if (ret == -ESHUTDOWN)
772 ret = call->error;
773
774 if (!dropped_lock)
775 mutex_unlock(&call->user_mutex);
776 _leave(" = %d", ret);
777 return ret;
778}
779EXPORT_SYMBOL(rxrpc_kernel_send_data);
780
781/**
782 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
783 * @sock: The socket the call is on
784 * @call: The call to be aborted
785 * @abort_code: The abort code to stick into the ABORT packet
786 * @error: Local error value
787 * @why: Indication as to why.
788 *
789 * Allow a kernel service to abort a call, if it's still in an abortable state
790 * and return true if the call was aborted, false if it was already complete.
791 */
792bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
793 u32 abort_code, int error, enum rxrpc_abort_reason why)
794{
795 bool aborted;
796
797 _enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
798
799 mutex_lock(&call->user_mutex);
800 aborted = rxrpc_propose_abort(call, abort_code, error, why);
801 mutex_unlock(&call->user_mutex);
802 return aborted;
803}
804EXPORT_SYMBOL(rxrpc_kernel_abort_call);
805
806/**
807 * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
808 * @sock: The socket the call is on
809 * @call: The call to be informed
810 * @tx_total_len: The amount of data to be transmitted for this call
811 *
812 * Allow a kernel service to set the total transmit length on a call. This
813 * allows buffer-to-packet encrypt-and-copy to be performed.
814 *
815 * This function is primarily for use for setting the reply length since the
816 * request length can be set when beginning the call.
817 */
818void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
819 s64 tx_total_len)
820{
821 WARN_ON(call->tx_total_len != -1);
822 call->tx_total_len = tx_total_len;
823}
824EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);
1/* AF_RXRPC sendmsg() implementation.
2 *
3 * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/net.h>
15#include <linux/gfp.h>
16#include <linux/skbuff.h>
17#include <linux/export.h>
18#include <linux/sched/signal.h>
19
20#include <net/sock.h>
21#include <net/af_rxrpc.h>
22#include "ar-internal.h"
23
24/*
25 * Wait for space to appear in the Tx queue or a signal to occur.
26 */
27static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
28 struct rxrpc_call *call,
29 long *timeo)
30{
31 for (;;) {
32 set_current_state(TASK_INTERRUPTIBLE);
33 if (call->tx_top - call->tx_hard_ack <
34 min_t(unsigned int, call->tx_winsize,
35 call->cong_cwnd + call->cong_extra))
36 return 0;
37
38 if (call->state >= RXRPC_CALL_COMPLETE)
39 return call->error;
40
41 if (signal_pending(current))
42 return sock_intr_errno(*timeo);
43
44 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
45 mutex_unlock(&call->user_mutex);
46 *timeo = schedule_timeout(*timeo);
47 if (mutex_lock_interruptible(&call->user_mutex) < 0)
48 return sock_intr_errno(*timeo);
49 }
50}
51
52/*
53 * Wait for space to appear in the Tx queue uninterruptibly, but with
54 * a timeout of 2*RTT if no progress was made and a signal occurred.
55 */
56static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
57 struct rxrpc_call *call)
58{
59 rxrpc_seq_t tx_start, tx_win;
60 signed long rtt2, timeout;
61 u64 rtt;
62
63 rtt = READ_ONCE(call->peer->rtt);
64 rtt2 = nsecs_to_jiffies64(rtt) * 2;
65 if (rtt2 < 1)
66 rtt2 = 1;
67
68 timeout = rtt2;
69 tx_start = READ_ONCE(call->tx_hard_ack);
70
71 for (;;) {
72 set_current_state(TASK_UNINTERRUPTIBLE);
73
74 tx_win = READ_ONCE(call->tx_hard_ack);
75 if (call->tx_top - tx_win <
76 min_t(unsigned int, call->tx_winsize,
77 call->cong_cwnd + call->cong_extra))
78 return 0;
79
80 if (call->state >= RXRPC_CALL_COMPLETE)
81 return call->error;
82
83 if (timeout == 0 &&
84 tx_win == tx_start && signal_pending(current))
85 return -EINTR;
86
87 if (tx_win != tx_start) {
88 timeout = rtt2;
89 tx_start = tx_win;
90 }
91
92 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
93 timeout = schedule_timeout(timeout);
94 }
95}
96
97/*
98 * wait for space to appear in the transmit/ACK window
99 * - caller holds the socket locked
100 */
101static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
102 struct rxrpc_call *call,
103 long *timeo,
104 bool waitall)
105{
106 DECLARE_WAITQUEUE(myself, current);
107 int ret;
108
109 _enter(",{%u,%u,%u}",
110 call->tx_hard_ack, call->tx_top, call->tx_winsize);
111
112 add_wait_queue(&call->waitq, &myself);
113
114 if (waitall)
115 ret = rxrpc_wait_for_tx_window_nonintr(rx, call);
116 else
117 ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
118
119 remove_wait_queue(&call->waitq, &myself);
120 set_current_state(TASK_RUNNING);
121 _leave(" = %d", ret);
122 return ret;
123}
124
125/*
126 * Schedule an instant Tx resend.
127 */
128static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
129{
130 spin_lock_bh(&call->lock);
131
132 if (call->state < RXRPC_CALL_COMPLETE) {
133 call->rxtx_annotations[ix] =
134 (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
135 RXRPC_TX_ANNO_RETRANS;
136 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
137 rxrpc_queue_call(call);
138 }
139
140 spin_unlock_bh(&call->lock);
141}
142
143/*
144 * Notify the owner of the call that the transmit phase is ended and the last
145 * packet has been queued.
146 */
147static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
148 rxrpc_notify_end_tx_t notify_end_tx)
149{
150 if (notify_end_tx)
151 notify_end_tx(&rx->sk, call, call->user_call_ID);
152}
153
154/*
155 * Queue a DATA packet for transmission, set the resend timeout and send the
156 * packet immediately
157 */
158static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
159 struct sk_buff *skb, bool last,
160 rxrpc_notify_end_tx_t notify_end_tx)
161{
162 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
163 unsigned long now;
164 rxrpc_seq_t seq = sp->hdr.seq;
165 int ret, ix;
166 u8 annotation = RXRPC_TX_ANNO_UNACK;
167
168 _net("queue skb %p [%d]", skb, seq);
169
170 ASSERTCMP(seq, ==, call->tx_top + 1);
171
172 if (last) {
173 annotation |= RXRPC_TX_ANNO_LAST;
174 set_bit(RXRPC_CALL_TX_LASTQ, &call->flags);
175 }
176
177 /* We have to set the timestamp before queueing as the retransmit
178 * algorithm can see the packet as soon as we queue it.
179 */
180 skb->tstamp = ktime_get_real();
181
182 ix = seq & RXRPC_RXTX_BUFF_MASK;
183 rxrpc_get_skb(skb, rxrpc_skb_tx_got);
184 call->rxtx_annotations[ix] = annotation;
185 smp_wmb();
186 call->rxtx_buffer[ix] = skb;
187 call->tx_top = seq;
188 if (last)
189 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
190 else
191 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
192
193 if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
194 _debug("________awaiting reply/ACK__________");
195 write_lock_bh(&call->state_lock);
196 switch (call->state) {
197 case RXRPC_CALL_CLIENT_SEND_REQUEST:
198 call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
199 rxrpc_notify_end_tx(rx, call, notify_end_tx);
200 break;
201 case RXRPC_CALL_SERVER_ACK_REQUEST:
202 call->state = RXRPC_CALL_SERVER_SEND_REPLY;
203 now = jiffies;
204 WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
205 if (call->ackr_reason == RXRPC_ACK_DELAY)
206 call->ackr_reason = 0;
207 trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
208 if (!last)
209 break;
210 /* Fall through */
211 case RXRPC_CALL_SERVER_SEND_REPLY:
212 call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
213 rxrpc_notify_end_tx(rx, call, notify_end_tx);
214 break;
215 default:
216 break;
217 }
218 write_unlock_bh(&call->state_lock);
219 }
220
221 if (seq == 1 && rxrpc_is_client_call(call))
222 rxrpc_expose_client_call(call);
223
224 ret = rxrpc_send_data_packet(call, skb, false);
225 if (ret < 0) {
226 switch (ret) {
227 case -ENETUNREACH:
228 case -EHOSTUNREACH:
229 case -ECONNREFUSED:
230 rxrpc_set_call_completion(call,
231 RXRPC_CALL_LOCAL_ERROR,
232 0, ret);
233 goto out;
234 }
235 _debug("need instant resend %d", ret);
236 rxrpc_instant_resend(call, ix);
237 } else {
238 unsigned long now = jiffies, resend_at;
239
240 if (call->peer->rtt_usage > 1)
241 resend_at = nsecs_to_jiffies(call->peer->rtt * 3 / 2);
242 else
243 resend_at = rxrpc_resend_timeout;
244 if (resend_at < 1)
245 resend_at = 1;
246
247 resend_at += now;
248 WRITE_ONCE(call->resend_at, resend_at);
249 rxrpc_reduce_call_timer(call, resend_at, now,
250 rxrpc_timer_set_for_send);
251 }
252
253out:
254 rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
255 _leave("");
256}
257
258/*
259 * send data through a socket
260 * - must be called in process context
261 * - The caller holds the call user access mutex, but not the socket lock.
262 */
263static int rxrpc_send_data(struct rxrpc_sock *rx,
264 struct rxrpc_call *call,
265 struct msghdr *msg, size_t len,
266 rxrpc_notify_end_tx_t notify_end_tx)
267{
268 struct rxrpc_skb_priv *sp;
269 struct sk_buff *skb;
270 struct sock *sk = &rx->sk;
271 long timeo;
272 bool more;
273 int ret, copied;
274
275 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
276
277 /* this should be in poll */
278 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
279
280 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
281 return -EPIPE;
282
283 more = msg->msg_flags & MSG_MORE;
284
285 if (call->tx_total_len != -1) {
286 if (len > call->tx_total_len)
287 return -EMSGSIZE;
288 if (!more && len != call->tx_total_len)
289 return -EMSGSIZE;
290 }
291
292 skb = call->tx_pending;
293 call->tx_pending = NULL;
294 rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
295
296 copied = 0;
297 do {
298 /* Check to see if there's a ping ACK to reply to. */
299 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
300 rxrpc_send_ack_packet(call, false, NULL);
301
302 if (!skb) {
303 size_t size, chunk, max, space;
304
305 _debug("alloc");
306
307 if (call->tx_top - call->tx_hard_ack >=
308 min_t(unsigned int, call->tx_winsize,
309 call->cong_cwnd + call->cong_extra)) {
310 ret = -EAGAIN;
311 if (msg->msg_flags & MSG_DONTWAIT)
312 goto maybe_error;
313 ret = rxrpc_wait_for_tx_window(rx, call,
314 &timeo,
315 msg->msg_flags & MSG_WAITALL);
316 if (ret < 0)
317 goto maybe_error;
318 }
319
320 max = RXRPC_JUMBO_DATALEN;
321 max -= call->conn->security_size;
322 max &= ~(call->conn->size_align - 1UL);
323
324 chunk = max;
325 if (chunk > msg_data_left(msg) && !more)
326 chunk = msg_data_left(msg);
327
328 space = chunk + call->conn->size_align;
329 space &= ~(call->conn->size_align - 1UL);
330
331 size = space + call->conn->security_size;
332
333 _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
334
335 /* create a buffer that we can retain until it's ACK'd */
336 skb = sock_alloc_send_skb(
337 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
338 if (!skb)
339 goto maybe_error;
340
341 rxrpc_new_skb(skb, rxrpc_skb_tx_new);
342
343 _debug("ALLOC SEND %p", skb);
344
345 ASSERTCMP(skb->mark, ==, 0);
346
347 _debug("HS: %u", call->conn->security_size);
348 skb_reserve(skb, call->conn->security_size);
349 skb->len += call->conn->security_size;
350
351 sp = rxrpc_skb(skb);
352 sp->remain = chunk;
353 if (sp->remain > skb_tailroom(skb))
354 sp->remain = skb_tailroom(skb);
355
356 _net("skb: hr %d, tr %d, hl %d, rm %d",
357 skb_headroom(skb),
358 skb_tailroom(skb),
359 skb_headlen(skb),
360 sp->remain);
361
362 skb->ip_summed = CHECKSUM_UNNECESSARY;
363 }
364
365 _debug("append");
366 sp = rxrpc_skb(skb);
367
368 /* append next segment of data to the current buffer */
369 if (msg_data_left(msg) > 0) {
370 int copy = skb_tailroom(skb);
371 ASSERTCMP(copy, >, 0);
372 if (copy > msg_data_left(msg))
373 copy = msg_data_left(msg);
374 if (copy > sp->remain)
375 copy = sp->remain;
376
377 _debug("add");
378 ret = skb_add_data(skb, &msg->msg_iter, copy);
379 _debug("added");
380 if (ret < 0)
381 goto efault;
382 sp->remain -= copy;
383 skb->mark += copy;
384 copied += copy;
385 if (call->tx_total_len != -1)
386 call->tx_total_len -= copy;
387 }
388
389 /* add the packet to the send queue if it's now full */
390 if (sp->remain <= 0 ||
391 (msg_data_left(msg) == 0 && !more)) {
392 struct rxrpc_connection *conn = call->conn;
393 uint32_t seq;
394 size_t pad;
395
396 /* pad out if we're using security */
397 if (conn->security_ix) {
398 pad = conn->security_size + skb->mark;
399 pad = conn->size_align - pad;
400 pad &= conn->size_align - 1;
401 _debug("pad %zu", pad);
402 if (pad)
403 skb_put_zero(skb, pad);
404 }
405
406 seq = call->tx_top + 1;
407
408 sp->hdr.seq = seq;
409 sp->hdr._rsvd = 0;
410 sp->hdr.flags = conn->out_clientflag;
411
412 if (msg_data_left(msg) == 0 && !more)
413 sp->hdr.flags |= RXRPC_LAST_PACKET;
414 else if (call->tx_top - call->tx_hard_ack <
415 call->tx_winsize)
416 sp->hdr.flags |= RXRPC_MORE_PACKETS;
417
418 ret = conn->security->secure_packet(
419 call, skb, skb->mark, skb->head);
420 if (ret < 0)
421 goto out;
422
423 rxrpc_queue_packet(rx, call, skb,
424 !msg_data_left(msg) && !more,
425 notify_end_tx);
426 skb = NULL;
427 }
428
429 /* Check for the far side aborting the call or a network error
430 * occurring. If this happens, save any packet that was under
431 * construction so that in the case of a network error, the
432 * call can be retried or redirected.
433 */
434 if (call->state == RXRPC_CALL_COMPLETE) {
435 ret = call->error;
436 goto out;
437 }
438 } while (msg_data_left(msg) > 0);
439
440success:
441 ret = copied;
442out:
443 call->tx_pending = skb;
444 _leave(" = %d", ret);
445 return ret;
446
447maybe_error:
448 if (copied)
449 goto success;
450 goto out;
451
452efault:
453 ret = -EFAULT;
454 goto out;
455}
456
457/*
458 * extract control messages from the sendmsg() control buffer
459 */
460static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
461{
462 struct cmsghdr *cmsg;
463 bool got_user_ID = false;
464 int len;
465
466 if (msg->msg_controllen == 0)
467 return -EINVAL;
468
469 for_each_cmsghdr(cmsg, msg) {
470 if (!CMSG_OK(msg, cmsg))
471 return -EINVAL;
472
473 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
474 _debug("CMSG %d, %d, %d",
475 cmsg->cmsg_level, cmsg->cmsg_type, len);
476
477 if (cmsg->cmsg_level != SOL_RXRPC)
478 continue;
479
480 switch (cmsg->cmsg_type) {
481 case RXRPC_USER_CALL_ID:
482 if (msg->msg_flags & MSG_CMSG_COMPAT) {
483 if (len != sizeof(u32))
484 return -EINVAL;
485 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
486 } else {
487 if (len != sizeof(unsigned long))
488 return -EINVAL;
489 p->call.user_call_ID = *(unsigned long *)
490 CMSG_DATA(cmsg);
491 }
492 got_user_ID = true;
493 break;
494
495 case RXRPC_ABORT:
496 if (p->command != RXRPC_CMD_SEND_DATA)
497 return -EINVAL;
498 p->command = RXRPC_CMD_SEND_ABORT;
499 if (len != sizeof(p->abort_code))
500 return -EINVAL;
501 p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
502 if (p->abort_code == 0)
503 return -EINVAL;
504 break;
505
506 case RXRPC_ACCEPT:
507 if (p->command != RXRPC_CMD_SEND_DATA)
508 return -EINVAL;
509 p->command = RXRPC_CMD_ACCEPT;
510 if (len != 0)
511 return -EINVAL;
512 break;
513
514 case RXRPC_EXCLUSIVE_CALL:
515 p->exclusive = true;
516 if (len != 0)
517 return -EINVAL;
518 break;
519
520 case RXRPC_UPGRADE_SERVICE:
521 p->upgrade = true;
522 if (len != 0)
523 return -EINVAL;
524 break;
525
526 case RXRPC_TX_LENGTH:
527 if (p->call.tx_total_len != -1 || len != sizeof(__s64))
528 return -EINVAL;
529 p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
530 if (p->call.tx_total_len < 0)
531 return -EINVAL;
532 break;
533
534 case RXRPC_SET_CALL_TIMEOUT:
535 if (len & 3 || len < 4 || len > 12)
536 return -EINVAL;
537 memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
538 p->call.nr_timeouts = len / 4;
539 if (p->call.timeouts.hard > INT_MAX / HZ)
540 return -ERANGE;
541 if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
542 return -ERANGE;
543 if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
544 return -ERANGE;
545 break;
546
547 default:
548 return -EINVAL;
549 }
550 }
551
552 if (!got_user_ID)
553 return -EINVAL;
554 if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
555 return -EINVAL;
556 _leave(" = 0");
557 return 0;
558}
559
560/*
561 * Create a new client call for sendmsg().
562 * - Called with the socket lock held, which it must release.
563 * - If it returns a call, the call's lock will need releasing by the caller.
564 */
565static struct rxrpc_call *
566rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
567 struct rxrpc_send_params *p)
568 __releases(&rx->sk.sk_lock.slock)
569 __acquires(&call->user_mutex)
570{
571 struct rxrpc_conn_parameters cp;
572 struct rxrpc_call *call;
573 struct key *key;
574
575 DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
576
577 _enter("");
578
579 if (!msg->msg_name) {
580 release_sock(&rx->sk);
581 return ERR_PTR(-EDESTADDRREQ);
582 }
583
584 key = rx->key;
585 if (key && !rx->key->payload.data[0])
586 key = NULL;
587
588 memset(&cp, 0, sizeof(cp));
589 cp.local = rx->local;
590 cp.key = rx->key;
591 cp.security_level = rx->min_sec_level;
592 cp.exclusive = rx->exclusive | p->exclusive;
593 cp.upgrade = p->upgrade;
594 cp.service_id = srx->srx_service;
595 call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
596 atomic_inc_return(&rxrpc_debug_id));
597 /* The socket is now unlocked */
598
599 rxrpc_put_peer(cp.peer);
600 _leave(" = %p\n", call);
601 return call;
602}
603
604/*
605 * send a message forming part of a client call through an RxRPC socket
606 * - caller holds the socket locked
607 * - the socket may be either a client socket or a server socket
608 */
609int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
610 __releases(&rx->sk.sk_lock.slock)
611 __releases(&call->user_mutex)
612{
613 enum rxrpc_call_state state;
614 struct rxrpc_call *call;
615 unsigned long now, j;
616 int ret;
617
618 struct rxrpc_send_params p = {
619 .call.tx_total_len = -1,
620 .call.user_call_ID = 0,
621 .call.nr_timeouts = 0,
622 .abort_code = 0,
623 .command = RXRPC_CMD_SEND_DATA,
624 .exclusive = false,
625 .upgrade = false,
626 };
627
628 _enter("");
629
630 ret = rxrpc_sendmsg_cmsg(msg, &p);
631 if (ret < 0)
632 goto error_release_sock;
633
634 if (p.command == RXRPC_CMD_ACCEPT) {
635 ret = -EINVAL;
636 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
637 goto error_release_sock;
638 call = rxrpc_accept_call(rx, p.call.user_call_ID, NULL);
639 /* The socket is now unlocked. */
640 if (IS_ERR(call))
641 return PTR_ERR(call);
642 ret = 0;
643 goto out_put_unlock;
644 }
645
646 call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
647 if (!call) {
648 ret = -EBADSLT;
649 if (p.command != RXRPC_CMD_SEND_DATA)
650 goto error_release_sock;
651 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
652 /* The socket is now unlocked... */
653 if (IS_ERR(call))
654 return PTR_ERR(call);
655 /* ... and we have the call lock. */
656 } else {
657 switch (READ_ONCE(call->state)) {
658 case RXRPC_CALL_UNINITIALISED:
659 case RXRPC_CALL_CLIENT_AWAIT_CONN:
660 case RXRPC_CALL_SERVER_PREALLOC:
661 case RXRPC_CALL_SERVER_SECURING:
662 case RXRPC_CALL_SERVER_ACCEPTING:
663 ret = -EBUSY;
664 goto error_release_sock;
665 default:
666 break;
667 }
668
669 ret = mutex_lock_interruptible(&call->user_mutex);
670 release_sock(&rx->sk);
671 if (ret < 0) {
672 ret = -ERESTARTSYS;
673 goto error_put;
674 }
675
676 if (p.call.tx_total_len != -1) {
677 ret = -EINVAL;
678 if (call->tx_total_len != -1 ||
679 call->tx_pending ||
680 call->tx_top != 0)
681 goto error_put;
682 call->tx_total_len = p.call.tx_total_len;
683 }
684 }
685
686 switch (p.call.nr_timeouts) {
687 case 3:
688 j = msecs_to_jiffies(p.call.timeouts.normal);
689 if (p.call.timeouts.normal > 0 && j == 0)
690 j = 1;
691 WRITE_ONCE(call->next_rx_timo, j);
692 /* Fall through */
693 case 2:
694 j = msecs_to_jiffies(p.call.timeouts.idle);
695 if (p.call.timeouts.idle > 0 && j == 0)
696 j = 1;
697 WRITE_ONCE(call->next_req_timo, j);
698 /* Fall through */
699 case 1:
700 if (p.call.timeouts.hard > 0) {
701 j = msecs_to_jiffies(p.call.timeouts.hard);
702 now = jiffies;
703 j += now;
704 WRITE_ONCE(call->expect_term_by, j);
705 rxrpc_reduce_call_timer(call, j, now,
706 rxrpc_timer_set_for_hard);
707 }
708 break;
709 }
710
711 state = READ_ONCE(call->state);
712 _debug("CALL %d USR %lx ST %d on CONN %p",
713 call->debug_id, call->user_call_ID, state, call->conn);
714
715 if (state >= RXRPC_CALL_COMPLETE) {
716 /* it's too late for this call */
717 ret = -ESHUTDOWN;
718 } else if (p.command == RXRPC_CMD_SEND_ABORT) {
719 ret = 0;
720 if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
721 ret = rxrpc_send_abort_packet(call);
722 } else if (p.command != RXRPC_CMD_SEND_DATA) {
723 ret = -EINVAL;
724 } else if (rxrpc_is_client_call(call) &&
725 state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
726 /* request phase complete for this client call */
727 ret = -EPROTO;
728 } else if (rxrpc_is_service_call(call) &&
729 state != RXRPC_CALL_SERVER_ACK_REQUEST &&
730 state != RXRPC_CALL_SERVER_SEND_REPLY) {
731 /* Reply phase not begun or not complete for service call. */
732 ret = -EPROTO;
733 } else {
734 ret = rxrpc_send_data(rx, call, msg, len, NULL);
735 }
736
737out_put_unlock:
738 mutex_unlock(&call->user_mutex);
739error_put:
740 rxrpc_put_call(call, rxrpc_call_put);
741 _leave(" = %d", ret);
742 return ret;
743
744error_release_sock:
745 release_sock(&rx->sk);
746 return ret;
747}
748
749/**
750 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
751 * @sock: The socket the call is on
752 * @call: The call to send data through
753 * @msg: The data to send
754 * @len: The amount of data to send
755 * @notify_end_tx: Notification that the last packet is queued.
756 *
757 * Allow a kernel service to send data on a call. The call must be in an state
758 * appropriate to sending data. No control data should be supplied in @msg,
759 * nor should an address be supplied. MSG_MORE should be flagged if there's
760 * more data to come, otherwise this data will end the transmission phase.
761 */
762int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
763 struct msghdr *msg, size_t len,
764 rxrpc_notify_end_tx_t notify_end_tx)
765{
766 int ret;
767
768 _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
769
770 ASSERTCMP(msg->msg_name, ==, NULL);
771 ASSERTCMP(msg->msg_control, ==, NULL);
772
773 mutex_lock(&call->user_mutex);
774
775 _debug("CALL %d USR %lx ST %d on CONN %p",
776 call->debug_id, call->user_call_ID, call->state, call->conn);
777
778 switch (READ_ONCE(call->state)) {
779 case RXRPC_CALL_CLIENT_SEND_REQUEST:
780 case RXRPC_CALL_SERVER_ACK_REQUEST:
781 case RXRPC_CALL_SERVER_SEND_REPLY:
782 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
783 notify_end_tx);
784 break;
785 case RXRPC_CALL_COMPLETE:
786 read_lock_bh(&call->state_lock);
787 ret = call->error;
788 read_unlock_bh(&call->state_lock);
789 break;
790 default:
791 /* Request phase complete for this client call */
792 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
793 ret = -EPROTO;
794 break;
795 }
796
797 mutex_unlock(&call->user_mutex);
798 _leave(" = %d", ret);
799 return ret;
800}
801EXPORT_SYMBOL(rxrpc_kernel_send_data);
802
803/**
804 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
805 * @sock: The socket the call is on
806 * @call: The call to be aborted
807 * @abort_code: The abort code to stick into the ABORT packet
808 * @error: Local error value
809 * @why: 3-char string indicating why.
810 *
811 * Allow a kernel service to abort a call, if it's still in an abortable state
812 * and return true if the call was aborted, false if it was already complete.
813 */
814bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
815 u32 abort_code, int error, const char *why)
816{
817 bool aborted;
818
819 _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
820
821 mutex_lock(&call->user_mutex);
822
823 aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
824 if (aborted)
825 rxrpc_send_abort_packet(call);
826
827 mutex_unlock(&call->user_mutex);
828 return aborted;
829}
830EXPORT_SYMBOL(rxrpc_kernel_abort_call);
831
832/**
833 * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
834 * @sock: The socket the call is on
835 * @call: The call to be informed
836 * @tx_total_len: The amount of data to be transmitted for this call
837 *
838 * Allow a kernel service to set the total transmit length on a call. This
839 * allows buffer-to-packet encrypt-and-copy to be performed.
840 *
841 * This function is primarily for use for setting the reply length since the
842 * request length can be set when beginning the call.
843 */
844void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
845 s64 tx_total_len)
846{
847 WARN_ON(call->tx_total_len != -1);
848 call->tx_total_len = tx_total_len;
849}
850EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);