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 */
rxrpc_check_tx_space(struct rxrpc_call * call,rxrpc_seq_t * _tx_win)23 static 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 */
rxrpc_wait_for_tx_window_intr(struct rxrpc_sock * rx,struct rxrpc_call * call,long * timeo)38 static 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 *timeo = schedule_timeout(*timeo);
55 }
56 }
57
58 /*
59 * Wait for space to appear in the Tx queue uninterruptibly, but with
60 * a timeout of 2*RTT if no progress was made and a signal occurred.
61 */
rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock * rx,struct rxrpc_call * call)62 static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
63 struct rxrpc_call *call)
64 {
65 rxrpc_seq_t tx_start, tx_win;
66 signed long rtt, timeout;
67
68 rtt = READ_ONCE(call->peer->srtt_us) >> 3;
69 rtt = usecs_to_jiffies(rtt) * 2;
70 if (rtt < 2)
71 rtt = 2;
72
73 timeout = rtt;
74 tx_start = READ_ONCE(call->tx_hard_ack);
75
76 for (;;) {
77 set_current_state(TASK_UNINTERRUPTIBLE);
78
79 tx_win = READ_ONCE(call->tx_hard_ack);
80 if (rxrpc_check_tx_space(call, &tx_win))
81 return 0;
82
83 if (call->state >= RXRPC_CALL_COMPLETE)
84 return call->error;
85
86 if (timeout == 0 &&
87 tx_win == tx_start && signal_pending(current))
88 return -EINTR;
89
90 if (tx_win != tx_start) {
91 timeout = rtt;
92 tx_start = tx_win;
93 }
94
95 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
96 timeout = schedule_timeout(timeout);
97 }
98 }
99
100 /*
101 * Wait for space to appear in the Tx queue uninterruptibly.
102 */
rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock * rx,struct rxrpc_call * call,long * timeo)103 static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
104 struct rxrpc_call *call,
105 long *timeo)
106 {
107 for (;;) {
108 set_current_state(TASK_UNINTERRUPTIBLE);
109 if (rxrpc_check_tx_space(call, NULL))
110 return 0;
111
112 if (call->state >= RXRPC_CALL_COMPLETE)
113 return call->error;
114
115 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
116 *timeo = schedule_timeout(*timeo);
117 }
118 }
119
120 /*
121 * wait for space to appear in the transmit/ACK window
122 * - caller holds the socket locked
123 */
rxrpc_wait_for_tx_window(struct rxrpc_sock * rx,struct rxrpc_call * call,long * timeo,bool waitall)124 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
125 struct rxrpc_call *call,
126 long *timeo,
127 bool waitall)
128 {
129 DECLARE_WAITQUEUE(myself, current);
130 int ret;
131
132 _enter(",{%u,%u,%u}",
133 call->tx_hard_ack, call->tx_top, call->tx_winsize);
134
135 add_wait_queue(&call->waitq, &myself);
136
137 switch (call->interruptibility) {
138 case RXRPC_INTERRUPTIBLE:
139 if (waitall)
140 ret = rxrpc_wait_for_tx_window_waitall(rx, call);
141 else
142 ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
143 break;
144 case RXRPC_PREINTERRUPTIBLE:
145 case RXRPC_UNINTERRUPTIBLE:
146 default:
147 ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
148 break;
149 }
150
151 remove_wait_queue(&call->waitq, &myself);
152 set_current_state(TASK_RUNNING);
153 _leave(" = %d", ret);
154 return ret;
155 }
156
157 /*
158 * Schedule an instant Tx resend.
159 */
rxrpc_instant_resend(struct rxrpc_call * call,int ix)160 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
161 {
162 spin_lock_bh(&call->lock);
163
164 if (call->state < RXRPC_CALL_COMPLETE) {
165 call->rxtx_annotations[ix] =
166 (call->rxtx_annotations[ix] & RXRPC_TX_ANNO_LAST) |
167 RXRPC_TX_ANNO_RETRANS;
168 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
169 rxrpc_queue_call(call);
170 }
171
172 spin_unlock_bh(&call->lock);
173 }
174
175 /*
176 * Notify the owner of the call that the transmit phase is ended and the last
177 * packet has been queued.
178 */
rxrpc_notify_end_tx(struct rxrpc_sock * rx,struct rxrpc_call * call,rxrpc_notify_end_tx_t notify_end_tx)179 static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
180 rxrpc_notify_end_tx_t notify_end_tx)
181 {
182 if (notify_end_tx)
183 notify_end_tx(&rx->sk, call, call->user_call_ID);
184 }
185
186 /*
187 * Queue a DATA packet for transmission, set the resend timeout and send
188 * the packet immediately. Returns the error from rxrpc_send_data_packet()
189 * in case the caller wants to do something with it.
190 */
rxrpc_queue_packet(struct rxrpc_sock * rx,struct rxrpc_call * call,struct sk_buff * skb,bool last,rxrpc_notify_end_tx_t notify_end_tx)191 static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
192 struct sk_buff *skb, bool last,
193 rxrpc_notify_end_tx_t notify_end_tx)
194 {
195 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
196 unsigned long now;
197 rxrpc_seq_t seq = sp->hdr.seq;
198 int ret, ix;
199 u8 annotation = RXRPC_TX_ANNO_UNACK;
200
201 _net("queue skb %p [%d]", skb, seq);
202
203 ASSERTCMP(seq, ==, call->tx_top + 1);
204
205 if (last)
206 annotation |= RXRPC_TX_ANNO_LAST;
207
208 /* We have to set the timestamp before queueing as the retransmit
209 * algorithm can see the packet as soon as we queue it.
210 */
211 skb->tstamp = ktime_get_real();
212
213 ix = seq & RXRPC_RXTX_BUFF_MASK;
214 rxrpc_get_skb(skb, rxrpc_skb_got);
215 call->rxtx_annotations[ix] = annotation;
216 smp_wmb();
217 call->rxtx_buffer[ix] = skb;
218 call->tx_top = seq;
219 if (last)
220 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
221 else
222 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
223
224 if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
225 _debug("________awaiting reply/ACK__________");
226 write_lock_bh(&call->state_lock);
227 switch (call->state) {
228 case RXRPC_CALL_CLIENT_SEND_REQUEST:
229 call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
230 rxrpc_notify_end_tx(rx, call, notify_end_tx);
231 break;
232 case RXRPC_CALL_SERVER_ACK_REQUEST:
233 call->state = RXRPC_CALL_SERVER_SEND_REPLY;
234 now = jiffies;
235 WRITE_ONCE(call->ack_at, now + MAX_JIFFY_OFFSET);
236 if (call->ackr_reason == RXRPC_ACK_DELAY)
237 call->ackr_reason = 0;
238 trace_rxrpc_timer(call, rxrpc_timer_init_for_send_reply, now);
239 if (!last)
240 break;
241 fallthrough;
242 case RXRPC_CALL_SERVER_SEND_REPLY:
243 call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
244 rxrpc_notify_end_tx(rx, call, notify_end_tx);
245 break;
246 default:
247 break;
248 }
249 write_unlock_bh(&call->state_lock);
250 }
251
252 if (seq == 1 && rxrpc_is_client_call(call))
253 rxrpc_expose_client_call(call);
254
255 ret = rxrpc_send_data_packet(call, skb, false);
256 if (ret < 0) {
257 switch (ret) {
258 case -ENETUNREACH:
259 case -EHOSTUNREACH:
260 case -ECONNREFUSED:
261 rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
262 0, ret);
263 goto out;
264 }
265 _debug("need instant resend %d", ret);
266 rxrpc_instant_resend(call, ix);
267 } else {
268 unsigned long now = jiffies;
269 unsigned long resend_at = now + call->peer->rto_j;
270
271 WRITE_ONCE(call->resend_at, resend_at);
272 rxrpc_reduce_call_timer(call, resend_at, now,
273 rxrpc_timer_set_for_send);
274 }
275
276 out:
277 rxrpc_free_skb(skb, rxrpc_skb_freed);
278 _leave(" = %d", ret);
279 return ret;
280 }
281
282 /*
283 * send data through a socket
284 * - must be called in process context
285 * - The caller holds the call user access mutex, but not the socket lock.
286 */
rxrpc_send_data(struct rxrpc_sock * rx,struct rxrpc_call * call,struct msghdr * msg,size_t len,rxrpc_notify_end_tx_t notify_end_tx,bool * _dropped_lock)287 static int rxrpc_send_data(struct rxrpc_sock *rx,
288 struct rxrpc_call *call,
289 struct msghdr *msg, size_t len,
290 rxrpc_notify_end_tx_t notify_end_tx,
291 bool *_dropped_lock)
292 {
293 struct rxrpc_skb_priv *sp;
294 struct sk_buff *skb;
295 struct sock *sk = &rx->sk;
296 enum rxrpc_call_state state;
297 long timeo;
298 bool more = msg->msg_flags & MSG_MORE;
299 int ret, copied = 0;
300
301 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
302
303 /* this should be in poll */
304 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
305
306 reload:
307 ret = -EPIPE;
308 if (sk->sk_shutdown & SEND_SHUTDOWN)
309 goto maybe_error;
310 state = READ_ONCE(call->state);
311 ret = -ESHUTDOWN;
312 if (state >= RXRPC_CALL_COMPLETE)
313 goto maybe_error;
314 ret = -EPROTO;
315 if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
316 state != RXRPC_CALL_SERVER_ACK_REQUEST &&
317 state != RXRPC_CALL_SERVER_SEND_REPLY)
318 goto maybe_error;
319
320 ret = -EMSGSIZE;
321 if (call->tx_total_len != -1) {
322 if (len - copied > call->tx_total_len)
323 goto maybe_error;
324 if (!more && len - copied != call->tx_total_len)
325 goto maybe_error;
326 }
327
328 skb = call->tx_pending;
329 call->tx_pending = NULL;
330 rxrpc_see_skb(skb, rxrpc_skb_seen);
331
332 do {
333 /* Check to see if there's a ping ACK to reply to. */
334 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
335 rxrpc_send_ack_packet(call, false, NULL);
336
337 if (!skb) {
338 size_t remain, bufsize, chunk, offset;
339
340 _debug("alloc");
341
342 if (!rxrpc_check_tx_space(call, NULL))
343 goto wait_for_space;
344
345 /* Work out the maximum size of a packet. Assume that
346 * the security header is going to be in the padded
347 * region (enc blocksize), but the trailer is not.
348 */
349 remain = more ? INT_MAX : msg_data_left(msg);
350 ret = call->conn->security->how_much_data(call, remain,
351 &bufsize, &chunk, &offset);
352 if (ret < 0)
353 goto maybe_error;
354
355 _debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
356
357 /* create a buffer that we can retain until it's ACK'd */
358 skb = sock_alloc_send_skb(
359 sk, bufsize, msg->msg_flags & MSG_DONTWAIT, &ret);
360 if (!skb)
361 goto maybe_error;
362
363 sp = rxrpc_skb(skb);
364 sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
365 rxrpc_new_skb(skb, rxrpc_skb_new);
366
367 _debug("ALLOC SEND %p", skb);
368
369 ASSERTCMP(skb->mark, ==, 0);
370
371 __skb_put(skb, offset);
372
373 sp->remain = chunk;
374 if (sp->remain > skb_tailroom(skb))
375 sp->remain = skb_tailroom(skb);
376
377 _net("skb: hr %d, tr %d, hl %d, rm %d",
378 skb_headroom(skb),
379 skb_tailroom(skb),
380 skb_headlen(skb),
381 sp->remain);
382
383 skb->ip_summed = CHECKSUM_UNNECESSARY;
384 }
385
386 _debug("append");
387 sp = rxrpc_skb(skb);
388
389 /* append next segment of data to the current buffer */
390 if (msg_data_left(msg) > 0) {
391 int copy = skb_tailroom(skb);
392 ASSERTCMP(copy, >, 0);
393 if (copy > msg_data_left(msg))
394 copy = msg_data_left(msg);
395 if (copy > sp->remain)
396 copy = sp->remain;
397
398 _debug("add");
399 ret = skb_add_data(skb, &msg->msg_iter, copy);
400 _debug("added");
401 if (ret < 0)
402 goto efault;
403 sp->remain -= copy;
404 skb->mark += copy;
405 copied += copy;
406 if (call->tx_total_len != -1)
407 call->tx_total_len -= copy;
408 }
409
410 /* check for the far side aborting the call or a network error
411 * occurring */
412 if (call->state == RXRPC_CALL_COMPLETE)
413 goto call_terminated;
414
415 /* add the packet to the send queue if it's now full */
416 if (sp->remain <= 0 ||
417 (msg_data_left(msg) == 0 && !more)) {
418 struct rxrpc_connection *conn = call->conn;
419 uint32_t seq;
420
421 seq = call->tx_top + 1;
422
423 sp->hdr.seq = seq;
424 sp->hdr._rsvd = 0;
425 sp->hdr.flags = conn->out_clientflag;
426
427 if (msg_data_left(msg) == 0 && !more)
428 sp->hdr.flags |= RXRPC_LAST_PACKET;
429 else if (call->tx_top - call->tx_hard_ack <
430 call->tx_winsize)
431 sp->hdr.flags |= RXRPC_MORE_PACKETS;
432
433 ret = call->security->secure_packet(call, skb, skb->mark);
434 if (ret < 0)
435 goto out;
436
437 ret = rxrpc_queue_packet(rx, call, skb,
438 !msg_data_left(msg) && !more,
439 notify_end_tx);
440 /* Should check for failure here */
441 skb = NULL;
442 }
443 } while (msg_data_left(msg) > 0);
444
445 success:
446 ret = copied;
447 if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE) {
448 read_lock_bh(&call->state_lock);
449 if (call->error < 0)
450 ret = call->error;
451 read_unlock_bh(&call->state_lock);
452 }
453 out:
454 call->tx_pending = skb;
455 _leave(" = %d", ret);
456 return ret;
457
458 call_terminated:
459 rxrpc_free_skb(skb, rxrpc_skb_freed);
460 _leave(" = %d", call->error);
461 return call->error;
462
463 maybe_error:
464 if (copied)
465 goto success;
466 goto out;
467
468 efault:
469 ret = -EFAULT;
470 goto out;
471
472 wait_for_space:
473 ret = -EAGAIN;
474 if (msg->msg_flags & MSG_DONTWAIT)
475 goto maybe_error;
476 mutex_unlock(&call->user_mutex);
477 *_dropped_lock = true;
478 ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
479 msg->msg_flags & MSG_WAITALL);
480 if (ret < 0)
481 goto maybe_error;
482 if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
483 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
484 ret = sock_intr_errno(timeo);
485 goto maybe_error;
486 }
487 } else {
488 mutex_lock(&call->user_mutex);
489 }
490 *_dropped_lock = false;
491 goto reload;
492 }
493
494 /*
495 * extract control messages from the sendmsg() control buffer
496 */
rxrpc_sendmsg_cmsg(struct msghdr * msg,struct rxrpc_send_params * p)497 static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
498 {
499 struct cmsghdr *cmsg;
500 bool got_user_ID = false;
501 int len;
502
503 if (msg->msg_controllen == 0)
504 return -EINVAL;
505
506 for_each_cmsghdr(cmsg, msg) {
507 if (!CMSG_OK(msg, cmsg))
508 return -EINVAL;
509
510 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
511 _debug("CMSG %d, %d, %d",
512 cmsg->cmsg_level, cmsg->cmsg_type, len);
513
514 if (cmsg->cmsg_level != SOL_RXRPC)
515 continue;
516
517 switch (cmsg->cmsg_type) {
518 case RXRPC_USER_CALL_ID:
519 if (msg->msg_flags & MSG_CMSG_COMPAT) {
520 if (len != sizeof(u32))
521 return -EINVAL;
522 p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
523 } else {
524 if (len != sizeof(unsigned long))
525 return -EINVAL;
526 p->call.user_call_ID = *(unsigned long *)
527 CMSG_DATA(cmsg);
528 }
529 got_user_ID = true;
530 break;
531
532 case RXRPC_ABORT:
533 if (p->command != RXRPC_CMD_SEND_DATA)
534 return -EINVAL;
535 p->command = RXRPC_CMD_SEND_ABORT;
536 if (len != sizeof(p->abort_code))
537 return -EINVAL;
538 p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
539 if (p->abort_code == 0)
540 return -EINVAL;
541 break;
542
543 case RXRPC_CHARGE_ACCEPT:
544 if (p->command != RXRPC_CMD_SEND_DATA)
545 return -EINVAL;
546 p->command = RXRPC_CMD_CHARGE_ACCEPT;
547 if (len != 0)
548 return -EINVAL;
549 break;
550
551 case RXRPC_EXCLUSIVE_CALL:
552 p->exclusive = true;
553 if (len != 0)
554 return -EINVAL;
555 break;
556
557 case RXRPC_UPGRADE_SERVICE:
558 p->upgrade = true;
559 if (len != 0)
560 return -EINVAL;
561 break;
562
563 case RXRPC_TX_LENGTH:
564 if (p->call.tx_total_len != -1 || len != sizeof(__s64))
565 return -EINVAL;
566 p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
567 if (p->call.tx_total_len < 0)
568 return -EINVAL;
569 break;
570
571 case RXRPC_SET_CALL_TIMEOUT:
572 if (len & 3 || len < 4 || len > 12)
573 return -EINVAL;
574 memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
575 p->call.nr_timeouts = len / 4;
576 if (p->call.timeouts.hard > INT_MAX / HZ)
577 return -ERANGE;
578 if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
579 return -ERANGE;
580 if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
581 return -ERANGE;
582 break;
583
584 default:
585 return -EINVAL;
586 }
587 }
588
589 if (!got_user_ID)
590 return -EINVAL;
591 if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
592 return -EINVAL;
593 _leave(" = 0");
594 return 0;
595 }
596
597 /*
598 * Create a new client call for sendmsg().
599 * - Called with the socket lock held, which it must release.
600 * - If it returns a call, the call's lock will need releasing by the caller.
601 */
602 static struct rxrpc_call *
rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock * rx,struct msghdr * msg,struct rxrpc_send_params * p)603 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
604 struct rxrpc_send_params *p)
605 __releases(&rx->sk.sk_lock.slock)
606 __acquires(&call->user_mutex)
607 {
608 struct rxrpc_conn_parameters cp;
609 struct rxrpc_call *call;
610 struct key *key;
611
612 DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
613
614 _enter("");
615
616 if (!msg->msg_name) {
617 release_sock(&rx->sk);
618 return ERR_PTR(-EDESTADDRREQ);
619 }
620
621 key = rx->key;
622 if (key && !rx->key->payload.data[0])
623 key = NULL;
624
625 memset(&cp, 0, sizeof(cp));
626 cp.local = rx->local;
627 cp.key = rx->key;
628 cp.security_level = rx->min_sec_level;
629 cp.exclusive = rx->exclusive | p->exclusive;
630 cp.upgrade = p->upgrade;
631 cp.service_id = srx->srx_service;
632 call = rxrpc_new_client_call(rx, &cp, srx, &p->call, GFP_KERNEL,
633 atomic_inc_return(&rxrpc_debug_id));
634 /* The socket is now unlocked */
635
636 rxrpc_put_peer(cp.peer);
637 _leave(" = %p\n", call);
638 return call;
639 }
640
641 /*
642 * send a message forming part of a client call through an RxRPC socket
643 * - caller holds the socket locked
644 * - the socket may be either a client socket or a server socket
645 */
rxrpc_do_sendmsg(struct rxrpc_sock * rx,struct msghdr * msg,size_t len)646 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
647 __releases(&rx->sk.sk_lock.slock)
648 __releases(&call->user_mutex)
649 {
650 enum rxrpc_call_state state;
651 struct rxrpc_call *call;
652 unsigned long now, j;
653 bool dropped_lock = false;
654 int ret;
655
656 struct rxrpc_send_params p = {
657 .call.tx_total_len = -1,
658 .call.user_call_ID = 0,
659 .call.nr_timeouts = 0,
660 .call.interruptibility = RXRPC_INTERRUPTIBLE,
661 .abort_code = 0,
662 .command = RXRPC_CMD_SEND_DATA,
663 .exclusive = false,
664 .upgrade = false,
665 };
666
667 _enter("");
668
669 ret = rxrpc_sendmsg_cmsg(msg, &p);
670 if (ret < 0)
671 goto error_release_sock;
672
673 if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
674 ret = -EINVAL;
675 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
676 goto error_release_sock;
677 ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
678 goto error_release_sock;
679 }
680
681 call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
682 if (!call) {
683 ret = -EBADSLT;
684 if (p.command != RXRPC_CMD_SEND_DATA)
685 goto error_release_sock;
686 call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
687 /* The socket is now unlocked... */
688 if (IS_ERR(call))
689 return PTR_ERR(call);
690 /* ... and we have the call lock. */
691 ret = 0;
692 if (READ_ONCE(call->state) == RXRPC_CALL_COMPLETE)
693 goto out_put_unlock;
694 } else {
695 switch (READ_ONCE(call->state)) {
696 case RXRPC_CALL_UNINITIALISED:
697 case RXRPC_CALL_CLIENT_AWAIT_CONN:
698 case RXRPC_CALL_SERVER_PREALLOC:
699 case RXRPC_CALL_SERVER_SECURING:
700 rxrpc_put_call(call, rxrpc_call_put);
701 ret = -EBUSY;
702 goto error_release_sock;
703 default:
704 break;
705 }
706
707 ret = mutex_lock_interruptible(&call->user_mutex);
708 release_sock(&rx->sk);
709 if (ret < 0) {
710 ret = -ERESTARTSYS;
711 goto error_put;
712 }
713
714 if (p.call.tx_total_len != -1) {
715 ret = -EINVAL;
716 if (call->tx_total_len != -1 ||
717 call->tx_pending ||
718 call->tx_top != 0)
719 goto error_put;
720 call->tx_total_len = p.call.tx_total_len;
721 }
722 }
723
724 switch (p.call.nr_timeouts) {
725 case 3:
726 j = msecs_to_jiffies(p.call.timeouts.normal);
727 if (p.call.timeouts.normal > 0 && j == 0)
728 j = 1;
729 WRITE_ONCE(call->next_rx_timo, j);
730 fallthrough;
731 case 2:
732 j = msecs_to_jiffies(p.call.timeouts.idle);
733 if (p.call.timeouts.idle > 0 && j == 0)
734 j = 1;
735 WRITE_ONCE(call->next_req_timo, j);
736 fallthrough;
737 case 1:
738 if (p.call.timeouts.hard > 0) {
739 j = msecs_to_jiffies(p.call.timeouts.hard);
740 now = jiffies;
741 j += now;
742 WRITE_ONCE(call->expect_term_by, j);
743 rxrpc_reduce_call_timer(call, j, now,
744 rxrpc_timer_set_for_hard);
745 }
746 break;
747 }
748
749 state = READ_ONCE(call->state);
750 _debug("CALL %d USR %lx ST %d on CONN %p",
751 call->debug_id, call->user_call_ID, state, call->conn);
752
753 if (state >= RXRPC_CALL_COMPLETE) {
754 /* it's too late for this call */
755 ret = -ESHUTDOWN;
756 } else if (p.command == RXRPC_CMD_SEND_ABORT) {
757 ret = 0;
758 if (rxrpc_abort_call("CMD", call, 0, p.abort_code, -ECONNABORTED))
759 ret = rxrpc_send_abort_packet(call);
760 } else if (p.command != RXRPC_CMD_SEND_DATA) {
761 ret = -EINVAL;
762 } else {
763 ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
764 }
765
766 out_put_unlock:
767 if (!dropped_lock)
768 mutex_unlock(&call->user_mutex);
769 error_put:
770 rxrpc_put_call(call, rxrpc_call_put);
771 _leave(" = %d", ret);
772 return ret;
773
774 error_release_sock:
775 release_sock(&rx->sk);
776 return ret;
777 }
778
779 /**
780 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
781 * @sock: The socket the call is on
782 * @call: The call to send data through
783 * @msg: The data to send
784 * @len: The amount of data to send
785 * @notify_end_tx: Notification that the last packet is queued.
786 *
787 * Allow a kernel service to send data on a call. The call must be in an state
788 * appropriate to sending data. No control data should be supplied in @msg,
789 * nor should an address be supplied. MSG_MORE should be flagged if there's
790 * more data to come, otherwise this data will end the transmission phase.
791 */
rxrpc_kernel_send_data(struct socket * sock,struct rxrpc_call * call,struct msghdr * msg,size_t len,rxrpc_notify_end_tx_t notify_end_tx)792 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
793 struct msghdr *msg, size_t len,
794 rxrpc_notify_end_tx_t notify_end_tx)
795 {
796 bool dropped_lock = false;
797 int ret;
798
799 _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
800
801 ASSERTCMP(msg->msg_name, ==, NULL);
802 ASSERTCMP(msg->msg_control, ==, NULL);
803
804 mutex_lock(&call->user_mutex);
805
806 _debug("CALL %d USR %lx ST %d on CONN %p",
807 call->debug_id, call->user_call_ID, call->state, call->conn);
808
809 switch (READ_ONCE(call->state)) {
810 case RXRPC_CALL_CLIENT_SEND_REQUEST:
811 case RXRPC_CALL_SERVER_ACK_REQUEST:
812 case RXRPC_CALL_SERVER_SEND_REPLY:
813 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
814 notify_end_tx, &dropped_lock);
815 break;
816 case RXRPC_CALL_COMPLETE:
817 read_lock_bh(&call->state_lock);
818 ret = call->error;
819 read_unlock_bh(&call->state_lock);
820 break;
821 default:
822 /* Request phase complete for this client call */
823 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
824 ret = -EPROTO;
825 break;
826 }
827
828 if (!dropped_lock)
829 mutex_unlock(&call->user_mutex);
830 _leave(" = %d", ret);
831 return ret;
832 }
833 EXPORT_SYMBOL(rxrpc_kernel_send_data);
834
835 /**
836 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
837 * @sock: The socket the call is on
838 * @call: The call to be aborted
839 * @abort_code: The abort code to stick into the ABORT packet
840 * @error: Local error value
841 * @why: 3-char string indicating why.
842 *
843 * Allow a kernel service to abort a call, if it's still in an abortable state
844 * and return true if the call was aborted, false if it was already complete.
845 */
rxrpc_kernel_abort_call(struct socket * sock,struct rxrpc_call * call,u32 abort_code,int error,const char * why)846 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
847 u32 abort_code, int error, const char *why)
848 {
849 bool aborted;
850
851 _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
852
853 mutex_lock(&call->user_mutex);
854
855 aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
856 if (aborted)
857 rxrpc_send_abort_packet(call);
858
859 mutex_unlock(&call->user_mutex);
860 return aborted;
861 }
862 EXPORT_SYMBOL(rxrpc_kernel_abort_call);
863
864 /**
865 * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
866 * @sock: The socket the call is on
867 * @call: The call to be informed
868 * @tx_total_len: The amount of data to be transmitted for this call
869 *
870 * Allow a kernel service to set the total transmit length on a call. This
871 * allows buffer-to-packet encrypt-and-copy to be performed.
872 *
873 * This function is primarily for use for setting the reply length since the
874 * request length can be set when beginning the call.
875 */
rxrpc_kernel_set_tx_length(struct socket * sock,struct rxrpc_call * call,s64 tx_total_len)876 void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
877 s64 tx_total_len)
878 {
879 WARN_ON(call->tx_total_len != -1);
880 call->tx_total_len = tx_total_len;
881 }
882 EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);
883
