Loading...
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 * Wait for space to appear in the Tx queue or a signal to occur.
22 */
23static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
24 struct rxrpc_call *call,
25 long *timeo)
26{
27 for (;;) {
28 set_current_state(TASK_INTERRUPTIBLE);
29 if (call->tx_top - call->tx_hard_ack <
30 min_t(unsigned int, call->tx_winsize,
31 call->cong_cwnd + call->cong_extra))
32 return 0;
33
34 if (call->state >= RXRPC_CALL_COMPLETE)
35 return call->error;
36
37 if (signal_pending(current))
38 return sock_intr_errno(*timeo);
39
40 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
41 mutex_unlock(&call->user_mutex);
42 *timeo = schedule_timeout(*timeo);
43 if (mutex_lock_interruptible(&call->user_mutex) < 0)
44 return sock_intr_errno(*timeo);
45 }
46}
47
48/*
49 * Wait for space to appear in the Tx queue uninterruptibly, but with
50 * a timeout of 2*RTT if no progress was made and a signal occurred.
51 */
52static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
53 struct rxrpc_call *call)
54{
55 rxrpc_seq_t tx_start, tx_win;
56 signed long rtt2, timeout;
57 u64 rtt;
58
59 rtt = READ_ONCE(call->peer->rtt);
60 rtt2 = nsecs_to_jiffies64(rtt) * 2;
61 if (rtt2 < 1)
62 rtt2 = 1;
63
64 timeout = rtt2;
65 tx_start = READ_ONCE(call->tx_hard_ack);
66
67 for (;;) {
68 set_current_state(TASK_UNINTERRUPTIBLE);
69
70 tx_win = READ_ONCE(call->tx_hard_ack);
71 if (call->tx_top - tx_win <
72 min_t(unsigned int, call->tx_winsize,
73 call->cong_cwnd + call->cong_extra))
74 return 0;
75
76 if (call->state >= RXRPC_CALL_COMPLETE)
77 return call->error;
78
79 if (test_bit(RXRPC_CALL_IS_INTR, &call->flags) &&
80 timeout == 0 &&
81 tx_win == tx_start && signal_pending(current))
82 return -EINTR;
83
84 if (tx_win != tx_start) {
85 timeout = rtt2;
86 tx_start = tx_win;
87 }
88
89 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
90 timeout = schedule_timeout(timeout);
91 }
92}
93
94/*
95 * wait for space to appear in the transmit/ACK window
96 * - caller holds the socket locked
97 */
98static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
99 struct rxrpc_call *call,
100 long *timeo,
101 bool waitall)
102{
103 DECLARE_WAITQUEUE(myself, current);
104 int ret;
105
106 _enter(",{%u,%u,%u}",
107 call->tx_hard_ack, call->tx_top, call->tx_winsize);
108
109 add_wait_queue(&call->waitq, &myself);
110
111 if (waitall)
112 ret = rxrpc_wait_for_tx_window_nonintr(rx, call);
113 else
114 ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
115
116 remove_wait_queue(&call->waitq, &myself);
117 set_current_state(TASK_RUNNING);
118 _leave(" = %d", ret);
119 return ret;
120}
121
122/*
123 * Schedule an instant Tx resend.
124 */
125static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
126{
127 spin_lock_bh(&call->lock);
128
129 if (call->state < RXRPC_CALL_COMPLETE) {
130 call->rxtx_annotations[ix] =
131 (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
132 RXRPC_TX_ANNO_RETRANS;
133 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
134 rxrpc_queue_call(call);
135 }
136
137 spin_unlock_bh(&call->lock);
138}
139
140/*
141 * Notify the owner of the call that the transmit phase is ended and the last
142 * packet has been queued.
143 */
144static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
145 rxrpc_notify_end_tx_t notify_end_tx)
146{
147 if (notify_end_tx)
148 notify_end_tx(&rx->sk, call, call->user_call_ID);
149}
150
151/*
152 * Queue a DATA packet for transmission, set the resend timeout and send
153 * the packet immediately. Returns the error from rxrpc_send_data_packet()
154 * in case the caller wants to do something with it.
155 */
156static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
157 struct sk_buff *skb, bool last,
158 rxrpc_notify_end_tx_t notify_end_tx)
159{
160 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
161 unsigned long now;
162 rxrpc_seq_t seq = sp->hdr.seq;
163 int ret, ix;
164 u8 annotation = RXRPC_TX_ANNO_UNACK;
165
166 _net("queue skb %p [%d]", skb, seq);
167
168 ASSERTCMP(seq, ==, call->tx_top + 1);
169
170 if (last)
171 annotation |= RXRPC_TX_ANNO_LAST;
172
173 /* We have to set the timestamp before queueing as the retransmit
174 * algorithm can see the packet as soon as we queue it.
175 */
176 skb->tstamp = ktime_get_real();
177
178 ix = seq & RXRPC_RXTX_BUFF_MASK;
179 rxrpc_get_skb(skb, rxrpc_skb_got);
180 call->rxtx_annotations[ix] = annotation;
181 smp_wmb();
182 call->rxtx_buffer[ix] = skb;
183 call->tx_top = seq;
184 if (last)
185 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
186 else
187 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
188
189 if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
190 _debug("________awaiting reply/ACK__________");
191 write_lock_bh(&call->state_lock);
192 switch (call->state) {
193 case RXRPC_CALL_CLIENT_SEND_REQUEST:
194 call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
195 rxrpc_notify_end_tx(rx, call, notify_end_tx);
196 break;
197 case RXRPC_CALL_SERVER_ACK_REQUEST:
198 call->state = RXRPC_CALL_SERVER_SEND_REPLY;
199 now = jiffies;
200 WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
201 if (call->ackr_reason == RXRPC_ACK_DELAY)
202 call->ackr_reason = 0;
203 trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
204 if (!last)
205 break;
206 /* Fall through */
207 case RXRPC_CALL_SERVER_SEND_REPLY:
208 call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
209 rxrpc_notify_end_tx(rx, call, notify_end_tx);
210 break;
211 default:
212 break;
213 }
214 write_unlock_bh(&call->state_lock);
215 }
216
217 if (seq == 1 && rxrpc_is_client_call(call))
218 rxrpc_expose_client_call(call);
219
220 ret = rxrpc_send_data_packet(call, skb, false);
221 if (ret < 0) {
222 switch (ret) {
223 case -ENETUNREACH:
224 case -EHOSTUNREACH:
225 case -ECONNREFUSED:
226 rxrpc_set_call_completion(call,
227 RXRPC_CALL_LOCAL_ERROR,
228 0, ret);
229 rxrpc_notify_socket(call);
230 goto out;
231 }
232 _debug("need instant resend %d", ret);
233 rxrpc_instant_resend(call, ix);
234 } else {
235 unsigned long now = jiffies, resend_at;
236
237 if (call->peer->rtt_usage > 1)
238 resend_at = nsecs_to_jiffies(call->peer->rtt * 3 / 2);
239 else
240 resend_at = rxrpc_resend_timeout;
241 if (resend_at < 1)
242 resend_at = 1;
243
244 resend_at += now;
245 WRITE_ONCE(call->resend_at, resend_at);
246 rxrpc_reduce_call_timer(call, resend_at, now,
247 rxrpc_timer_set_for_send);
248 }
249
250out:
251 rxrpc_free_skb(skb, rxrpc_skb_freed);
252 _leave(" = %d", ret);
253 return ret;
254}
255
256/*
257 * send data through a socket
258 * - must be called in process context
259 * - The caller holds the call user access mutex, but not the socket lock.
260 */
261static int rxrpc_send_data(struct rxrpc_sock *rx,
262 struct rxrpc_call *call,
263 struct msghdr *msg, size_t len,
264 rxrpc_notify_end_tx_t notify_end_tx)
265{
266 struct rxrpc_skb_priv *sp;
267 struct sk_buff *skb;
268 struct sock *sk = &rx->sk;
269 long timeo;
270 bool more;
271 int ret, copied;
272
273 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
274
275 /* this should be in poll */
276 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
277
278 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
279 return -EPIPE;
280
281 more = msg->msg_flags & MSG_MORE;
282
283 if (call->tx_total_len != -1) {
284 if (len > call->tx_total_len)
285 return -EMSGSIZE;
286 if (!more && len != call->tx_total_len)
287 return -EMSGSIZE;
288 }
289
290 skb = call->tx_pending;
291 call->tx_pending = NULL;
292 rxrpc_see_skb(skb, rxrpc_skb_seen);
293
294 copied = 0;
295 do {
296 /* Check to see if there's a ping ACK to reply to. */
297 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
298 rxrpc_send_ack_packet(call, false, NULL);
299
300 if (!skb) {
301 size_t size, chunk, max, space;
302
303 _debug("alloc");
304
305 if (call->tx_top - call->tx_hard_ack >=
306 min_t(unsigned int, call->tx_winsize,
307 call->cong_cwnd + call->cong_extra)) {
308 ret = -EAGAIN;
309 if (msg->msg_flags & MSG_DONTWAIT)
310 goto maybe_error;
311 ret = rxrpc_wait_for_tx_window(rx, call,
312 &timeo,
313 msg->msg_flags & MSG_WAITALL);
314 if (ret < 0)
315 goto maybe_error;
316 }
317
318 max = RXRPC_JUMBO_DATALEN;
319 max -= call->conn->security_size;
320 max &= ~(call->conn->size_align - 1UL);
321
322 chunk = max;
323 if (chunk > msg_data_left(msg) && !more)
324 chunk = msg_data_left(msg);
325
326 space = chunk + call->conn->size_align;
327 space &= ~(call->conn->size_align - 1UL);
328
329 size = space + call->conn->security_size;
330
331 _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
332
333 /* create a buffer that we can retain until it's ACK'd */
334 skb = sock_alloc_send_skb(
335 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
336 if (!skb)
337 goto maybe_error;
338
339 sp = rxrpc_skb(skb);
340 sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
341 rxrpc_new_skb(skb, rxrpc_skb_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->remain = chunk;
352 if (sp->remain > skb_tailroom(skb))
353 sp->remain = skb_tailroom(skb);
354
355 _net("skb: hr %d, tr %d, hl %d, rm %d",
356 skb_headroom(skb),
357 skb_tailroom(skb),
358 skb_headlen(skb),
359 sp->remain);
360
361 skb->ip_summed = CHECKSUM_UNNECESSARY;
362 }
363
364 _debug("append");
365 sp = rxrpc_skb(skb);
366
367 /* append next segment of data to the current buffer */
368 if (msg_data_left(msg) > 0) {
369 int copy = skb_tailroom(skb);
370 ASSERTCMP(copy, >, 0);
371 if (copy > msg_data_left(msg))
372 copy = msg_data_left(msg);
373 if (copy > sp->remain)
374 copy = sp->remain;
375
376 _debug("add");
377 ret = skb_add_data(skb, &msg->msg_iter, copy);
378 _debug("added");
379 if (ret < 0)
380 goto efault;
381 sp->remain -= copy;
382 skb->mark += copy;
383 copied += copy;
384 if (call->tx_total_len != -1)
385 call->tx_total_len -= copy;
386 }
387
388 /* check for the far side aborting the call or a network error
389 * occurring */
390 if (call->state == RXRPC_CALL_COMPLETE)
391 goto call_terminated;
392
393 /* add the packet to the send queue if it's now full */
394 if (sp->remain <= 0 ||
395 (msg_data_left(msg) == 0 && !more)) {
396 struct rxrpc_connection *conn = call->conn;
397 uint32_t seq;
398 size_t pad;
399
400 /* pad out if we're using security */
401 if (conn->security_ix) {
402 pad = conn->security_size + skb->mark;
403 pad = conn->size_align - pad;
404 pad &= conn->size_align - 1;
405 _debug("pad %zu", pad);
406 if (pad)
407 skb_put_zero(skb, pad);
408 }
409
410 seq = call->tx_top + 1;
411
412 sp->hdr.seq = seq;
413 sp->hdr._rsvd = 0;
414 sp->hdr.flags = conn->out_clientflag;
415
416 if (msg_data_left(msg) == 0 && !more)
417 sp->hdr.flags |= RXRPC_LAST_PACKET;
418 else if (call->tx_top - call->tx_hard_ack <
419 call->tx_winsize)
420 sp->hdr.flags |= RXRPC_MORE_PACKETS;
421
422 ret = call->security->secure_packet(
423 call, skb, skb->mark, skb->head);
424 if (ret < 0)
425 goto out;
426
427 ret = rxrpc_queue_packet(rx, call, skb,
428 !msg_data_left(msg) && !more,
429 notify_end_tx);
430 /* Should check for failure here */
431 skb = NULL;
432 }
433 } while (msg_data_left(msg) > 0);
434
435success:
436 ret = copied;
437out:
438 call->tx_pending = skb;
439 _leave(" = %d", ret);
440 return ret;
441
442call_terminated:
443 rxrpc_free_skb(skb, rxrpc_skb_freed);
444 _leave(" = %d", call->error);
445 return call->error;
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 .call.intr = true,
623 .abort_code = 0,
624 .command = RXRPC_CMD_SEND_DATA,
625 .exclusive = false,
626 .upgrade = false,
627 };
628
629 _enter("");
630
631 ret = rxrpc_sendmsg_cmsg(msg, &p);
632 if (ret < 0)
633 goto error_release_sock;
634
635 if (p.command == RXRPC_CMD_ACCEPT) {
636 ret = -EINVAL;
637 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
638 goto error_release_sock;
639 call = rxrpc_accept_call(rx, p.call.user_call_ID, NULL);
640 /* The socket is now unlocked. */
641 if (IS_ERR(call))
642 return PTR_ERR(call);
643 ret = 0;
644 goto out_put_unlock;
645 }
646
647 call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
648 if (!call) {
649 ret = -EBADSLT;
650 if (p.command != RXRPC_CMD_SEND_DATA)
651 goto error_release_sock;
652 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
653 /* The socket is now unlocked... */
654 if (IS_ERR(call))
655 return PTR_ERR(call);
656 /* ... and we have the call lock. */
657 } else {
658 switch (READ_ONCE(call->state)) {
659 case RXRPC_CALL_UNINITIALISED:
660 case RXRPC_CALL_CLIENT_AWAIT_CONN:
661 case RXRPC_CALL_SERVER_PREALLOC:
662 case RXRPC_CALL_SERVER_SECURING:
663 case RXRPC_CALL_SERVER_ACCEPTING:
664 rxrpc_put_call(call, rxrpc_call_put);
665 ret = -EBUSY;
666 goto error_release_sock;
667 default:
668 break;
669 }
670
671 ret = mutex_lock_interruptible(&call->user_mutex);
672 release_sock(&rx->sk);
673 if (ret < 0) {
674 ret = -ERESTARTSYS;
675 goto error_put;
676 }
677
678 if (p.call.tx_total_len != -1) {
679 ret = -EINVAL;
680 if (call->tx_total_len != -1 ||
681 call->tx_pending ||
682 call->tx_top != 0)
683 goto error_put;
684 call->tx_total_len = p.call.tx_total_len;
685 }
686 }
687
688 switch (p.call.nr_timeouts) {
689 case 3:
690 j = msecs_to_jiffies(p.call.timeouts.normal);
691 if (p.call.timeouts.normal > 0 && j == 0)
692 j = 1;
693 WRITE_ONCE(call->next_rx_timo, j);
694 /* Fall through */
695 case 2:
696 j = msecs_to_jiffies(p.call.timeouts.idle);
697 if (p.call.timeouts.idle > 0 && j == 0)
698 j = 1;
699 WRITE_ONCE(call->next_req_timo, j);
700 /* Fall through */
701 case 1:
702 if (p.call.timeouts.hard > 0) {
703 j = msecs_to_jiffies(p.call.timeouts.hard);
704 now = jiffies;
705 j += now;
706 WRITE_ONCE(call->expect_term_by, j);
707 rxrpc_reduce_call_timer(call, j, now,
708 rxrpc_timer_set_for_hard);
709 }
710 break;
711 }
712
713 state = READ_ONCE(call->state);
714 _debug("CALL %d USR %lx ST %d on CONN %p",
715 call->debug_id, call->user_call_ID, state, call->conn);
716
717 if (state >= RXRPC_CALL_COMPLETE) {
718 /* it's too late for this call */
719 ret = -ESHUTDOWN;
720 } else if (p.command == RXRPC_CMD_SEND_ABORT) {
721 ret = 0;
722 if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
723 ret = rxrpc_send_abort_packet(call);
724 } else if (p.command != RXRPC_CMD_SEND_DATA) {
725 ret = -EINVAL;
726 } else if (rxrpc_is_client_call(call) &&
727 state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
728 /* request phase complete for this client call */
729 ret = -EPROTO;
730 } else if (rxrpc_is_service_call(call) &&
731 state != RXRPC_CALL_SERVER_ACK_REQUEST &&
732 state != RXRPC_CALL_SERVER_SEND_REPLY) {
733 /* Reply phase not begun or not complete for service call. */
734 ret = -EPROTO;
735 } else {
736 ret = rxrpc_send_data(rx, call, msg, len, NULL);
737 }
738
739out_put_unlock:
740 mutex_unlock(&call->user_mutex);
741error_put:
742 rxrpc_put_call(call, rxrpc_call_put);
743 _leave(" = %d", ret);
744 return ret;
745
746error_release_sock:
747 release_sock(&rx->sk);
748 return ret;
749}
750
751/**
752 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
753 * @sock: The socket the call is on
754 * @call: The call to send data through
755 * @msg: The data to send
756 * @len: The amount of data to send
757 * @notify_end_tx: Notification that the last packet is queued.
758 *
759 * Allow a kernel service to send data on a call. The call must be in an state
760 * appropriate to sending data. No control data should be supplied in @msg,
761 * nor should an address be supplied. MSG_MORE should be flagged if there's
762 * more data to come, otherwise this data will end the transmission phase.
763 */
764int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
765 struct msghdr *msg, size_t len,
766 rxrpc_notify_end_tx_t notify_end_tx)
767{
768 int ret;
769
770 _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
771
772 ASSERTCMP(msg->msg_name, ==, NULL);
773 ASSERTCMP(msg->msg_control, ==, NULL);
774
775 mutex_lock(&call->user_mutex);
776
777 _debug("CALL %d USR %lx ST %d on CONN %p",
778 call->debug_id, call->user_call_ID, call->state, call->conn);
779
780 switch (READ_ONCE(call->state)) {
781 case RXRPC_CALL_CLIENT_SEND_REQUEST:
782 case RXRPC_CALL_SERVER_ACK_REQUEST:
783 case RXRPC_CALL_SERVER_SEND_REPLY:
784 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
785 notify_end_tx);
786 break;
787 case RXRPC_CALL_COMPLETE:
788 read_lock_bh(&call->state_lock);
789 ret = call->error;
790 read_unlock_bh(&call->state_lock);
791 break;
792 default:
793 /* Request phase complete for this client call */
794 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
795 ret = -EPROTO;
796 break;
797 }
798
799 mutex_unlock(&call->user_mutex);
800 _leave(" = %d", ret);
801 return ret;
802}
803EXPORT_SYMBOL(rxrpc_kernel_send_data);
804
805/**
806 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
807 * @sock: The socket the call is on
808 * @call: The call to be aborted
809 * @abort_code: The abort code to stick into the ABORT packet
810 * @error: Local error value
811 * @why: 3-char string indicating why.
812 *
813 * Allow a kernel service to abort a call, if it's still in an abortable state
814 * and return true if the call was aborted, false if it was already complete.
815 */
816bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
817 u32 abort_code, int error, const char *why)
818{
819 bool aborted;
820
821 _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
822
823 mutex_lock(&call->user_mutex);
824
825 aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
826 if (aborted)
827 rxrpc_send_abort_packet(call);
828
829 mutex_unlock(&call->user_mutex);
830 return aborted;
831}
832EXPORT_SYMBOL(rxrpc_kernel_abort_call);
833
834/**
835 * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
836 * @sock: The socket the call is on
837 * @call: The call to be informed
838 * @tx_total_len: The amount of data to be transmitted for this call
839 *
840 * Allow a kernel service to set the total transmit length on a call. This
841 * allows buffer-to-packet encrypt-and-copy to be performed.
842 *
843 * This function is primarily for use for setting the reply length since the
844 * request length can be set when beginning the call.
845 */
846void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
847 s64 tx_total_len)
848{
849 WARN_ON(call->tx_total_len != -1);
850 call->tx_total_len = tx_total_len;
851}
852EXPORT_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);