Loading...
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);
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 * Return true if there's sufficient Tx queue space.
22 */
23static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
24{
25 unsigned int win_size =
26 min_t(unsigned int, call->tx_winsize,
27 call->cong_cwnd + call->cong_extra);
28 rxrpc_seq_t tx_win = READ_ONCE(call->tx_hard_ack);
29
30 if (_tx_win)
31 *_tx_win = tx_win;
32 return call->tx_top - tx_win < win_size;
33}
34
35/*
36 * Wait for space to appear in the Tx queue or a signal to occur.
37 */
38static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
39 struct rxrpc_call *call,
40 long *timeo)
41{
42 for (;;) {
43 set_current_state(TASK_INTERRUPTIBLE);
44 if (rxrpc_check_tx_space(call, NULL))
45 return 0;
46
47 if (call->state >= RXRPC_CALL_COMPLETE)
48 return call->error;
49
50 if (signal_pending(current))
51 return sock_intr_errno(*timeo);
52
53 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
54 mutex_unlock(&call->user_mutex);
55 *timeo = schedule_timeout(*timeo);
56 if (mutex_lock_interruptible(&call->user_mutex) < 0)
57 return sock_intr_errno(*timeo);
58 }
59}
60
61/*
62 * Wait for space to appear in the Tx queue uninterruptibly, but with
63 * a timeout of 2*RTT if no progress was made and a signal occurred.
64 */
65static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
66 struct rxrpc_call *call)
67{
68 rxrpc_seq_t tx_start, tx_win;
69 signed long rtt, timeout;
70
71 rtt = READ_ONCE(call->peer->srtt_us) >> 3;
72 rtt = usecs_to_jiffies(rtt) * 2;
73 if (rtt < 2)
74 rtt = 2;
75
76 timeout = rtt;
77 tx_start = READ_ONCE(call->tx_hard_ack);
78
79 for (;;) {
80 set_current_state(TASK_UNINTERRUPTIBLE);
81
82 tx_win = READ_ONCE(call->tx_hard_ack);
83 if (rxrpc_check_tx_space(call, &tx_win))
84 return 0;
85
86 if (call->state >= RXRPC_CALL_COMPLETE)
87 return call->error;
88
89 if (timeout == 0 &&
90 tx_win == tx_start && signal_pending(current))
91 return -EINTR;
92
93 if (tx_win != tx_start) {
94 timeout = rtt;
95 tx_start = tx_win;
96 }
97
98 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
99 timeout = schedule_timeout(timeout);
100 }
101}
102
103/*
104 * Wait for space to appear in the Tx queue uninterruptibly.
105 */
106static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
107 struct rxrpc_call *call,
108 long *timeo)
109{
110 for (;;) {
111 set_current_state(TASK_UNINTERRUPTIBLE);
112 if (rxrpc_check_tx_space(call, NULL))
113 return 0;
114
115 if (call->state >= RXRPC_CALL_COMPLETE)
116 return call->error;
117
118 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
119 *timeo = schedule_timeout(*timeo);
120 }
121}
122
123/*
124 * wait for space to appear in the transmit/ACK window
125 * - caller holds the socket locked
126 */
127static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
128 struct rxrpc_call *call,
129 long *timeo,
130 bool waitall)
131{
132 DECLARE_WAITQUEUE(myself, current);
133 int ret;
134
135 _enter(",{%u,%u,%u}",
136 call->tx_hard_ack, call->tx_top, call->tx_winsize);
137
138 add_wait_queue(&call->waitq, &myself);
139
140 switch (call->interruptibility) {
141 case RXRPC_INTERRUPTIBLE:
142 if (waitall)
143 ret = rxrpc_wait_for_tx_window_waitall(rx, call);
144 else
145 ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
146 break;
147 case RXRPC_PREINTERRUPTIBLE:
148 case RXRPC_UNINTERRUPTIBLE:
149 default:
150 ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
151 break;
152 }
153
154 remove_wait_queue(&call->waitq, &myself);
155 set_current_state(TASK_RUNNING);
156 _leave(" = %d", ret);
157 return ret;
158}
159
160/*
161 * Schedule an instant Tx resend.
162 */
163static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
164{
165 spin_lock_bh(&call->lock);
166
167 if (call->state < RXRPC_CALL_COMPLETE) {
168 call->rxtx_annotations[ix] =
169 (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
170 RXRPC_TX_ANNO_RETRANS;
171 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
172 rxrpc_queue_call(call);
173 }
174
175 spin_unlock_bh(&call->lock);
176}
177
178/*
179 * Notify the owner of the call that the transmit phase is ended and the last
180 * packet has been queued.
181 */
182static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
183 rxrpc_notify_end_tx_t notify_end_tx)
184{
185 if (notify_end_tx)
186 notify_end_tx(&rx->sk, call, call->user_call_ID);
187}
188
189/*
190 * Queue a DATA packet for transmission, set the resend timeout and send
191 * the packet immediately. Returns the error from rxrpc_send_data_packet()
192 * in case the caller wants to do something with it.
193 */
194static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
195 struct sk_buff *skb, bool last,
196 rxrpc_notify_end_tx_t notify_end_tx)
197{
198 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
199 unsigned long now;
200 rxrpc_seq_t seq = sp->hdr.seq;
201 int ret, ix;
202 u8 annotation = RXRPC_TX_ANNO_UNACK;
203
204 _net("queue skb %p [%d]", skb, seq);
205
206 ASSERTCMP(seq, ==, call->tx_top + 1);
207
208 if (last)
209 annotation |= RXRPC_TX_ANNO_LAST;
210
211 /* We have to set the timestamp before queueing as the retransmit
212 * algorithm can see the packet as soon as we queue it.
213 */
214 skb->tstamp = ktime_get_real();
215
216 ix = seq & RXRPC_RXTX_BUFF_MASK;
217 rxrpc_get_skb(skb, rxrpc_skb_got);
218 call->rxtx_annotations[ix] = annotation;
219 smp_wmb();
220 call->rxtx_buffer[ix] = skb;
221 call->tx_top = seq;
222 if (last)
223 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
224 else
225 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
226
227 if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
228 _debug("________awaiting reply/ACK__________");
229 write_lock_bh(&call->state_lock);
230 switch (call->state) {
231 case RXRPC_CALL_CLIENT_SEND_REQUEST:
232 call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
233 rxrpc_notify_end_tx(rx, call, notify_end_tx);
234 break;
235 case RXRPC_CALL_SERVER_ACK_REQUEST:
236 call->state = RXRPC_CALL_SERVER_SEND_REPLY;
237 now = jiffies;
238 WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
239 if (call->ackr_reason == RXRPC_ACK_DELAY)
240 call->ackr_reason = 0;
241 trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
242 if (!last)
243 break;
244 fallthrough;
245 case RXRPC_CALL_SERVER_SEND_REPLY:
246 call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
247 rxrpc_notify_end_tx(rx, call, notify_end_tx);
248 break;
249 default:
250 break;
251 }
252 write_unlock_bh(&call->state_lock);
253 }
254
255 if (seq == 1 && rxrpc_is_client_call(call))
256 rxrpc_expose_client_call(call);
257
258 ret = rxrpc_send_data_packet(call, skb, false);
259 if (ret < 0) {
260 switch (ret) {
261 case -ENETUNREACH:
262 case -EHOSTUNREACH:
263 case -ECONNREFUSED:
264 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
265 0, ret);
266 goto out;
267 }
268 _debug("need instant resend %d", ret);
269 rxrpc_instant_resend(call, ix);
270 } else {
271 unsigned long now = jiffies;
272 unsigned long resend_at = now + call->peer->rto_j;
273
274 WRITE_ONCE(call->resend_at, resend_at);
275 rxrpc_reduce_call_timer(call, resend_at, now,
276 rxrpc_timer_set_for_send);
277 }
278
279out:
280 rxrpc_free_skb(skb, rxrpc_skb_freed);
281 _leave(" = %d", ret);
282 return ret;
283}
284
285/*
286 * send data through a socket
287 * - must be called in process context
288 * - The caller holds the call user access mutex, but not the socket lock.
289 */
290static int rxrpc_send_data(struct rxrpc_sock *rx,
291 struct rxrpc_call *call,
292 struct msghdr *msg, size_t len,
293 rxrpc_notify_end_tx_t notify_end_tx)
294{
295 struct rxrpc_skb_priv *sp;
296 struct sk_buff *skb;
297 struct sock *sk = &rx->sk;
298 long timeo;
299 bool more;
300 int ret, copied;
301
302 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
303
304 /* this should be in poll */
305 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
306
307 if (sk->sk_shutdown & SEND_SHUTDOWN)
308 return -EPIPE;
309
310 more = msg->msg_flags & MSG_MORE;
311
312 if (call->tx_total_len != -1) {
313 if (len > call->tx_total_len)
314 return -EMSGSIZE;
315 if (!more && len != call->tx_total_len)
316 return -EMSGSIZE;
317 }
318
319 skb = call->tx_pending;
320 call->tx_pending = NULL;
321 rxrpc_see_skb(skb, rxrpc_skb_seen);
322
323 copied = 0;
324 do {
325 /* Check to see if there's a ping ACK to reply to. */
326 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
327 rxrpc_send_ack_packet(call, false, NULL);
328
329 if (!skb) {
330 size_t size, chunk, max, space;
331
332 _debug("alloc");
333
334 if (!rxrpc_check_tx_space(call, NULL)) {
335 ret = -EAGAIN;
336 if (msg->msg_flags & MSG_DONTWAIT)
337 goto maybe_error;
338 ret = rxrpc_wait_for_tx_window(rx, call,
339 &timeo,
340 msg->msg_flags & MSG_WAITALL);
341 if (ret < 0)
342 goto maybe_error;
343 }
344
345 max = RXRPC_JUMBO_DATALEN;
346 max -= call->conn->security_size;
347 max &= ~(call->conn->size_align - 1UL);
348
349 chunk = max;
350 if (chunk > msg_data_left(msg) && !more)
351 chunk = msg_data_left(msg);
352
353 space = chunk + call->conn->size_align;
354 space &= ~(call->conn->size_align - 1UL);
355
356 size = space + call->conn->security_size;
357
358 _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
359
360 /* create a buffer that we can retain until it's ACK'd */
361 skb = sock_alloc_send_skb(
362 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
363 if (!skb)
364 goto maybe_error;
365
366 sp = rxrpc_skb(skb);
367 sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
368 rxrpc_new_skb(skb, rxrpc_skb_new);
369
370 _debug("ALLOC SEND %p", skb);
371
372 ASSERTCMP(skb->mark, ==, 0);
373
374 _debug("HS: %u", call->conn->security_size);
375 skb_reserve(skb, call->conn->security_size);
376 skb->len += call->conn->security_size;
377
378 sp->remain = chunk;
379 if (sp->remain > skb_tailroom(skb))
380 sp->remain = skb_tailroom(skb);
381
382 _net("skb: hr %d, tr %d, hl %d, rm %d",
383 skb_headroom(skb),
384 skb_tailroom(skb),
385 skb_headlen(skb),
386 sp->remain);
387
388 skb->ip_summed = CHECKSUM_UNNECESSARY;
389 }
390
391 _debug("append");
392 sp = rxrpc_skb(skb);
393
394 /* append next segment of data to the current buffer */
395 if (msg_data_left(msg) > 0) {
396 int copy = skb_tailroom(skb);
397 ASSERTCMP(copy, >, 0);
398 if (copy > msg_data_left(msg))
399 copy = msg_data_left(msg);
400 if (copy > sp->remain)
401 copy = sp->remain;
402
403 _debug("add");
404 ret = skb_add_data(skb, &msg->msg_iter, copy);
405 _debug("added");
406 if (ret < 0)
407 goto efault;
408 sp->remain -= copy;
409 skb->mark += copy;
410 copied += copy;
411 if (call->tx_total_len != -1)
412 call->tx_total_len -= copy;
413 }
414
415 /* check for the far side aborting the call or a network error
416 * occurring */
417 if (call->state == RXRPC_CALL_COMPLETE)
418 goto call_terminated;
419
420 /* add the packet to the send queue if it's now full */
421 if (sp->remain <= 0 ||
422 (msg_data_left(msg) == 0 && !more)) {
423 struct rxrpc_connection *conn = call->conn;
424 uint32_t seq;
425 size_t pad;
426
427 /* pad out if we're using security */
428 if (conn->security_ix) {
429 pad = conn->security_size + skb->mark;
430 pad = conn->size_align - pad;
431 pad &= conn->size_align - 1;
432 _debug("pad %zu", pad);
433 if (pad)
434 skb_put_zero(skb, pad);
435 }
436
437 seq = call->tx_top + 1;
438
439 sp->hdr.seq = seq;
440 sp->hdr._rsvd = 0;
441 sp->hdr.flags = conn->out_clientflag;
442
443 if (msg_data_left(msg) == 0 && !more)
444 sp->hdr.flags |= RXRPC_LAST_PACKET;
445 else if (call->tx_top - call->tx_hard_ack <
446 call->tx_winsize)
447 sp->hdr.flags |= RXRPC_MORE_PACKETS;
448
449 ret = call->security->secure_packet(
450 call, skb, skb->mark, skb->head);
451 if (ret < 0)
452 goto out;
453
454 ret = rxrpc_queue_packet(rx, call, skb,
455 !msg_data_left(msg) && !more,
456 notify_end_tx);
457 /* Should check for failure here */
458 skb = NULL;
459 }
460 } while (msg_data_left(msg) > 0);
461
462success:
463 ret = copied;
464out:
465 call->tx_pending = skb;
466 _leave(" = %d", ret);
467 return ret;
468
469call_terminated:
470 rxrpc_free_skb(skb, rxrpc_skb_freed);
471 _leave(" = %d", call->error);
472 return call->error;
473
474maybe_error:
475 if (copied)
476 goto success;
477 goto out;
478
479efault:
480 ret = -EFAULT;
481 goto out;
482}
483
484/*
485 * extract control messages from the sendmsg() control buffer
486 */
487static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
488{
489 struct cmsghdr *cmsg;
490 bool got_user_ID = false;
491 int len;
492
493 if (msg->msg_controllen == 0)
494 return -EINVAL;
495
496 for_each_cmsghdr(cmsg, msg) {
497 if (!CMSG_OK(msg, cmsg))
498 return -EINVAL;
499
500 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
501 _debug("CMSG %d, %d, %d",
502 cmsg->cmsg_level, cmsg->cmsg_type, len);
503
504 if (cmsg->cmsg_level != SOL_RXRPC)
505 continue;
506
507 switch (cmsg->cmsg_type) {
508 case RXRPC_USER_CALL_ID:
509 if (msg->msg_flags & MSG_CMSG_COMPAT) {
510 if (len != sizeof(u32))
511 return -EINVAL;
512 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
513 } else {
514 if (len != sizeof(unsigned long))
515 return -EINVAL;
516 p->call.user_call_ID = *(unsigned long *)
517 CMSG_DATA(cmsg);
518 }
519 got_user_ID = true;
520 break;
521
522 case RXRPC_ABORT:
523 if (p->command != RXRPC_CMD_SEND_DATA)
524 return -EINVAL;
525 p->command = RXRPC_CMD_SEND_ABORT;
526 if (len != sizeof(p->abort_code))
527 return -EINVAL;
528 p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
529 if (p->abort_code == 0)
530 return -EINVAL;
531 break;
532
533 case RXRPC_CHARGE_ACCEPT:
534 if (p->command != RXRPC_CMD_SEND_DATA)
535 return -EINVAL;
536 p->command = RXRPC_CMD_CHARGE_ACCEPT;
537 if (len != 0)
538 return -EINVAL;
539 break;
540
541 case RXRPC_EXCLUSIVE_CALL:
542 p->exclusive = true;
543 if (len != 0)
544 return -EINVAL;
545 break;
546
547 case RXRPC_UPGRADE_SERVICE:
548 p->upgrade = true;
549 if (len != 0)
550 return -EINVAL;
551 break;
552
553 case RXRPC_TX_LENGTH:
554 if (p->call.tx_total_len != -1 || len != sizeof(__s64))
555 return -EINVAL;
556 p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
557 if (p->call.tx_total_len < 0)
558 return -EINVAL;
559 break;
560
561 case RXRPC_SET_CALL_TIMEOUT:
562 if (len & 3 || len < 4 || len > 12)
563 return -EINVAL;
564 memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
565 p->call.nr_timeouts = len / 4;
566 if (p->call.timeouts.hard > INT_MAX / HZ)
567 return -ERANGE;
568 if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
569 return -ERANGE;
570 if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
571 return -ERANGE;
572 break;
573
574 default:
575 return -EINVAL;
576 }
577 }
578
579 if (!got_user_ID)
580 return -EINVAL;
581 if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
582 return -EINVAL;
583 _leave(" = 0");
584 return 0;
585}
586
587/*
588 * Create a new client call for sendmsg().
589 * - Called with the socket lock held, which it must release.
590 * - If it returns a call, the call's lock will need releasing by the caller.
591 */
592static struct rxrpc_call *
593rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
594 struct rxrpc_send_params *p)
595 __releases(&rx->sk.sk_lock.slock)
596 __acquires(&call->user_mutex)
597{
598 struct rxrpc_conn_parameters cp;
599 struct rxrpc_call *call;
600 struct key *key;
601
602 DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
603
604 _enter("");
605
606 if (!msg->msg_name) {
607 release_sock(&rx->sk);
608 return ERR_PTR(-EDESTADDRREQ);
609 }
610
611 key = rx->key;
612 if (key && !rx->key->payload.data[0])
613 key = NULL;
614
615 memset(&cp, 0, sizeof(cp));
616 cp.local = rx->local;
617 cp.key = rx->key;
618 cp.security_level = rx->min_sec_level;
619 cp.exclusive = rx->exclusive | p->exclusive;
620 cp.upgrade = p->upgrade;
621 cp.service_id = srx->srx_service;
622 call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
623 atomic_inc_return(&rxrpc_debug_id));
624 /* The socket is now unlocked */
625
626 rxrpc_put_peer(cp.peer);
627 _leave(" = %p\n", call);
628 return call;
629}
630
631/*
632 * send a message forming part of a client call through an RxRPC socket
633 * - caller holds the socket locked
634 * - the socket may be either a client socket or a server socket
635 */
636int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
637 __releases(&rx->sk.sk_lock.slock)
638 __releases(&call->user_mutex)
639{
640 enum rxrpc_call_state state;
641 struct rxrpc_call *call;
642 unsigned long now, j;
643 int ret;
644
645 struct rxrpc_send_params p = {
646 .call.tx_total_len = -1,
647 .call.user_call_ID = 0,
648 .call.nr_timeouts = 0,
649 .call.interruptibility = RXRPC_INTERRUPTIBLE,
650 .abort_code = 0,
651 .command = RXRPC_CMD_SEND_DATA,
652 .exclusive = false,
653 .upgrade = false,
654 };
655
656 _enter("");
657
658 ret = rxrpc_sendmsg_cmsg(msg, &p);
659 if (ret < 0)
660 goto error_release_sock;
661
662 if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
663 ret = -EINVAL;
664 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
665 goto error_release_sock;
666 ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
667 goto error_release_sock;
668 }
669
670 call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
671 if (!call) {
672 ret = -EBADSLT;
673 if (p.command != RXRPC_CMD_SEND_DATA)
674 goto error_release_sock;
675 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
676 /* The socket is now unlocked... */
677 if (IS_ERR(call))
678 return PTR_ERR(call);
679 /* ... and we have the call lock. */
680 ret = 0;
681 if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE)
682 goto out_put_unlock;
683 } else {
684 switch (READ_ONCE(call->state)) {
685 case RXRPC_CALL_UNINITIALISED:
686 case RXRPC_CALL_CLIENT_AWAIT_CONN:
687 case RXRPC_CALL_SERVER_PREALLOC:
688 case RXRPC_CALL_SERVER_SECURING:
689 rxrpc_put_call(call, rxrpc_call_put);
690 ret = -EBUSY;
691 goto error_release_sock;
692 default:
693 break;
694 }
695
696 ret = mutex_lock_interruptible(&call->user_mutex);
697 release_sock(&rx->sk);
698 if (ret < 0) {
699 ret = -ERESTARTSYS;
700 goto error_put;
701 }
702
703 if (p.call.tx_total_len != -1) {
704 ret = -EINVAL;
705 if (call->tx_total_len != -1 ||
706 call->tx_pending ||
707 call->tx_top != 0)
708 goto error_put;
709 call->tx_total_len = p.call.tx_total_len;
710 }
711 }
712
713 switch (p.call.nr_timeouts) {
714 case 3:
715 j = msecs_to_jiffies(p.call.timeouts.normal);
716 if (p.call.timeouts.normal > 0 && j == 0)
717 j = 1;
718 WRITE_ONCE(call->next_rx_timo, j);
719 fallthrough;
720 case 2:
721 j = msecs_to_jiffies(p.call.timeouts.idle);
722 if (p.call.timeouts.idle > 0 && j == 0)
723 j = 1;
724 WRITE_ONCE(call->next_req_timo, j);
725 fallthrough;
726 case 1:
727 if (p.call.timeouts.hard > 0) {
728 j = msecs_to_jiffies(p.call.timeouts.hard);
729 now = jiffies;
730 j += now;
731 WRITE_ONCE(call->expect_term_by, j);
732 rxrpc_reduce_call_timer(call, j, now,
733 rxrpc_timer_set_for_hard);
734 }
735 break;
736 }
737
738 state = READ_ONCE(call->state);
739 _debug("CALL %d USR %lx ST %d on CONN %p",
740 call->debug_id, call->user_call_ID, state, call->conn);
741
742 if (state >= RXRPC_CALL_COMPLETE) {
743 /* it's too late for this call */
744 ret = -ESHUTDOWN;
745 } else if (p.command == RXRPC_CMD_SEND_ABORT) {
746 ret = 0;
747 if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
748 ret = rxrpc_send_abort_packet(call);
749 } else if (p.command != RXRPC_CMD_SEND_DATA) {
750 ret = -EINVAL;
751 } else if (rxrpc_is_client_call(call) &&
752 state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
753 /* request phase complete for this client call */
754 ret = -EPROTO;
755 } else if (rxrpc_is_service_call(call) &&
756 state != RXRPC_CALL_SERVER_ACK_REQUEST &&
757 state != RXRPC_CALL_SERVER_SEND_REPLY) {
758 /* Reply phase not begun or not complete for service call. */
759 ret = -EPROTO;
760 } else {
761 ret = rxrpc_send_data(rx, call, msg, len, NULL);
762 }
763
764out_put_unlock:
765 mutex_unlock(&call->user_mutex);
766error_put:
767 rxrpc_put_call(call, rxrpc_call_put);
768 _leave(" = %d", ret);
769 return ret;
770
771error_release_sock:
772 release_sock(&rx->sk);
773 return ret;
774}
775
776/**
777 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
778 * @sock: The socket the call is on
779 * @call: The call to send data through
780 * @msg: The data to send
781 * @len: The amount of data to send
782 * @notify_end_tx: Notification that the last packet is queued.
783 *
784 * Allow a kernel service to send data on a call. The call must be in an state
785 * appropriate to sending data. No control data should be supplied in @msg,
786 * nor should an address be supplied. MSG_MORE should be flagged if there's
787 * more data to come, otherwise this data will end the transmission phase.
788 */
789int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
790 struct msghdr *msg, size_t len,
791 rxrpc_notify_end_tx_t notify_end_tx)
792{
793 int ret;
794
795 _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
796
797 ASSERTCMP(msg->msg_name, ==, NULL);
798 ASSERTCMP(msg->msg_control, ==, NULL);
799
800 mutex_lock(&call->user_mutex);
801
802 _debug("CALL %d USR %lx ST %d on CONN %p",
803 call->debug_id, call->user_call_ID, call->state, call->conn);
804
805 switch (READ_ONCE(call->state)) {
806 case RXRPC_CALL_CLIENT_SEND_REQUEST:
807 case RXRPC_CALL_SERVER_ACK_REQUEST:
808 case RXRPC_CALL_SERVER_SEND_REPLY:
809 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
810 notify_end_tx);
811 break;
812 case RXRPC_CALL_COMPLETE:
813 read_lock_bh(&call->state_lock);
814 ret = call->error;
815 read_unlock_bh(&call->state_lock);
816 break;
817 default:
818 /* Request phase complete for this client call */
819 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
820 ret = -EPROTO;
821 break;
822 }
823
824 mutex_unlock(&call->user_mutex);
825 _leave(" = %d", ret);
826 return ret;
827}
828EXPORT_SYMBOL(rxrpc_kernel_send_data);
829
830/**
831 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
832 * @sock: The socket the call is on
833 * @call: The call to be aborted
834 * @abort_code: The abort code to stick into the ABORT packet
835 * @error: Local error value
836 * @why: 3-char string indicating why.
837 *
838 * Allow a kernel service to abort a call, if it's still in an abortable state
839 * and return true if the call was aborted, false if it was already complete.
840 */
841bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
842 u32 abort_code, int error, const char *why)
843{
844 bool aborted;
845
846 _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
847
848 mutex_lock(&call->user_mutex);
849
850 aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
851 if (aborted)
852 rxrpc_send_abort_packet(call);
853
854 mutex_unlock(&call->user_mutex);
855 return aborted;
856}
857EXPORT_SYMBOL(rxrpc_kernel_abort_call);
858
859/**
860 * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
861 * @sock: The socket the call is on
862 * @call: The call to be informed
863 * @tx_total_len: The amount of data to be transmitted for this call
864 *
865 * Allow a kernel service to set the total transmit length on a call. This
866 * allows buffer-to-packet encrypt-and-copy to be performed.
867 *
868 * This function is primarily for use for setting the reply length since the
869 * request length can be set when beginning the call.
870 */
871void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
872 s64 tx_total_len)
873{
874 WARN_ON(call->tx_total_len != -1);
875 call->tx_total_len = tx_total_len;
876}
877EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);