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v5.9
  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);
v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* AF_RXRPC sendmsg() implementation.
  3 *
  4 * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
  5 * Written by David Howells (dhowells@redhat.com)
  6 */
  7
  8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  9
 10#include <linux/net.h>
 11#include <linux/gfp.h>
 12#include <linux/skbuff.h>
 13#include <linux/export.h>
 14#include <linux/sched/signal.h>
 15
 16#include <net/sock.h>
 17#include <net/af_rxrpc.h>
 18#include "ar-internal.h"
 19
 20/*
 21 * Propose an abort to be made in the I/O thread.
 22 */
 23bool rxrpc_propose_abort(struct rxrpc_call *call, s32 abort_code, int error,
 24			 enum rxrpc_abort_reason why)
 25{
 26	_enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
 27
 28	if (!call->send_abort && !rxrpc_call_is_complete(call)) {
 29		call->send_abort_why = why;
 30		call->send_abort_err = error;
 31		call->send_abort_seq = 0;
 32		/* Request abort locklessly vs rxrpc_input_call_event(). */
 33		smp_store_release(&call->send_abort, abort_code);
 34		rxrpc_poke_call(call, rxrpc_call_poke_abort);
 35		return true;
 36	}
 37
 38	return false;
 39}
 40
 41/*
 42 * Wait for a call to become connected.  Interruption here doesn't cause the
 43 * call to be aborted.
 44 */
 45static int rxrpc_wait_to_be_connected(struct rxrpc_call *call, long *timeo)
 46{
 47	DECLARE_WAITQUEUE(myself, current);
 48	int ret = 0;
 49
 50	_enter("%d", call->debug_id);
 51
 52	if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN)
 53		goto no_wait;
 54
 55	add_wait_queue_exclusive(&call->waitq, &myself);
 56
 57	for (;;) {
 58		switch (call->interruptibility) {
 59		case RXRPC_INTERRUPTIBLE:
 60		case RXRPC_PREINTERRUPTIBLE:
 61			set_current_state(TASK_INTERRUPTIBLE);
 62			break;
 63		case RXRPC_UNINTERRUPTIBLE:
 64		default:
 65			set_current_state(TASK_UNINTERRUPTIBLE);
 66			break;
 67		}
 68
 69		if (rxrpc_call_state(call) != RXRPC_CALL_CLIENT_AWAIT_CONN)
 70			break;
 71		if ((call->interruptibility == RXRPC_INTERRUPTIBLE ||
 72		     call->interruptibility == RXRPC_PREINTERRUPTIBLE) &&
 73		    signal_pending(current)) {
 74			ret = sock_intr_errno(*timeo);
 75			break;
 76		}
 77		*timeo = schedule_timeout(*timeo);
 78	}
 79
 80	remove_wait_queue(&call->waitq, &myself);
 81	__set_current_state(TASK_RUNNING);
 82
 83no_wait:
 84	if (ret == 0 && rxrpc_call_is_complete(call))
 85		ret = call->error;
 86
 87	_leave(" = %d", ret);
 88	return ret;
 89}
 90
 91/*
 92 * Return true if there's sufficient Tx queue space.
 93 */
 94static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
 95{
 
 
 
 
 
 96	if (_tx_win)
 97		*_tx_win = call->tx_bottom;
 98	return call->tx_prepared - call->tx_bottom < 256;
 99}
100
101/*
102 * Wait for space to appear in the Tx queue or a signal to occur.
103 */
104static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
105					 struct rxrpc_call *call,
106					 long *timeo)
107{
108	for (;;) {
109		set_current_state(TASK_INTERRUPTIBLE);
110		if (rxrpc_check_tx_space(call, NULL))
111			return 0;
112
113		if (rxrpc_call_is_complete(call))
114			return call->error;
115
116		if (signal_pending(current))
117			return sock_intr_errno(*timeo);
118
119		trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
 
120		*timeo = schedule_timeout(*timeo);
 
 
121	}
122}
123
124/*
125 * Wait for space to appear in the Tx queue uninterruptibly, but with
126 * a timeout of 2*RTT if no progress was made and a signal occurred.
127 */
128static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
129					    struct rxrpc_call *call)
130{
131	rxrpc_seq_t tx_start, tx_win;
132	signed long rtt, timeout;
133
134	rtt = READ_ONCE(call->peer->srtt_us) >> 3;
135	rtt = usecs_to_jiffies(rtt) * 2;
136	if (rtt < 2)
137		rtt = 2;
138
139	timeout = rtt;
140	tx_start = smp_load_acquire(&call->acks_hard_ack);
141
142	for (;;) {
143		set_current_state(TASK_UNINTERRUPTIBLE);
144
 
145		if (rxrpc_check_tx_space(call, &tx_win))
146			return 0;
147
148		if (rxrpc_call_is_complete(call))
149			return call->error;
150
151		if (timeout == 0 &&
152		    tx_win == tx_start && signal_pending(current))
153			return -EINTR;
154
155		if (tx_win != tx_start) {
156			timeout = rtt;
157			tx_start = tx_win;
158		}
159
160		trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
161		timeout = schedule_timeout(timeout);
162	}
163}
164
165/*
166 * Wait for space to appear in the Tx queue uninterruptibly.
167 */
168static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
169					    struct rxrpc_call *call,
170					    long *timeo)
171{
172	for (;;) {
173		set_current_state(TASK_UNINTERRUPTIBLE);
174		if (rxrpc_check_tx_space(call, NULL))
175			return 0;
176
177		if (rxrpc_call_is_complete(call))
178			return call->error;
179
180		trace_rxrpc_txqueue(call, rxrpc_txqueue_wait);
181		*timeo = schedule_timeout(*timeo);
182	}
183}
184
185/*
186 * wait for space to appear in the transmit/ACK window
187 * - caller holds the socket locked
188 */
189static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
190				    struct rxrpc_call *call,
191				    long *timeo,
192				    bool waitall)
193{
194	DECLARE_WAITQUEUE(myself, current);
195	int ret;
196
197	_enter(",{%u,%u,%u,%u}",
198	       call->tx_bottom, call->acks_hard_ack, call->tx_top, call->tx_winsize);
199
200	add_wait_queue(&call->waitq, &myself);
201
202	switch (call->interruptibility) {
203	case RXRPC_INTERRUPTIBLE:
204		if (waitall)
205			ret = rxrpc_wait_for_tx_window_waitall(rx, call);
206		else
207			ret = rxrpc_wait_for_tx_window_intr(rx, call, timeo);
208		break;
209	case RXRPC_PREINTERRUPTIBLE:
210	case RXRPC_UNINTERRUPTIBLE:
211	default:
212		ret = rxrpc_wait_for_tx_window_nonintr(rx, call, timeo);
213		break;
214	}
215
216	remove_wait_queue(&call->waitq, &myself);
217	set_current_state(TASK_RUNNING);
218	_leave(" = %d", ret);
219	return ret;
220}
221
222/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
223 * Notify the owner of the call that the transmit phase is ended and the last
224 * packet has been queued.
225 */
226static void rxrpc_notify_end_tx(struct rxrpc_sock *rx, struct rxrpc_call *call,
227				rxrpc_notify_end_tx_t notify_end_tx)
228{
229	if (notify_end_tx)
230		notify_end_tx(&rx->sk, call, call->user_call_ID);
231}
232
233/*
234 * Queue a DATA packet for transmission, set the resend timeout and send
235 * the packet immediately.  Returns the error from rxrpc_send_data_packet()
236 * in case the caller wants to do something with it.
237 */
238static void rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
239			       struct rxrpc_txbuf *txb,
240			       rxrpc_notify_end_tx_t notify_end_tx)
241{
242	rxrpc_seq_t seq = txb->seq;
243	bool last = test_bit(RXRPC_TXBUF_LAST, &txb->flags), poke;
 
 
 
 
 
244
245	rxrpc_inc_stat(call->rxnet, stat_tx_data);
246
247	ASSERTCMP(txb->seq, ==, call->tx_prepared + 1);
 
248
249	/* We have to set the timestamp before queueing as the retransmit
250	 * algorithm can see the packet as soon as we queue it.
251	 */
252	txb->last_sent = ktime_get_real();
253
 
 
 
 
 
 
254	if (last)
255		trace_rxrpc_txqueue(call, rxrpc_txqueue_queue_last);
256	else
257		trace_rxrpc_txqueue(call, rxrpc_txqueue_queue);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
258
259	/* Add the packet to the call's output buffer */
260	spin_lock(&call->tx_lock);
261	poke = list_empty(&call->tx_sendmsg);
262	list_add_tail(&txb->call_link, &call->tx_sendmsg);
263	call->tx_prepared = seq;
264	if (last)
265		rxrpc_notify_end_tx(rx, call, notify_end_tx);
266	spin_unlock(&call->tx_lock);
267
268	if (poke)
269		rxrpc_poke_call(call, rxrpc_call_poke_start);
 
 
270}
271
272/*
273 * send data through a socket
274 * - must be called in process context
275 * - The caller holds the call user access mutex, but not the socket lock.
276 */
277static int rxrpc_send_data(struct rxrpc_sock *rx,
278			   struct rxrpc_call *call,
279			   struct msghdr *msg, size_t len,
280			   rxrpc_notify_end_tx_t notify_end_tx,
281			   bool *_dropped_lock)
282{
283	struct rxrpc_txbuf *txb;
 
284	struct sock *sk = &rx->sk;
285	enum rxrpc_call_state state;
286	long timeo;
287	bool more = msg->msg_flags & MSG_MORE;
288	int ret, copied = 0;
289
290	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
291
292	ret = rxrpc_wait_to_be_connected(call, &timeo);
293	if (ret < 0)
294		return ret;
295
296	if (call->conn->state == RXRPC_CONN_CLIENT_UNSECURED) {
297		ret = rxrpc_init_client_conn_security(call->conn);
298		if (ret < 0)
299			return ret;
300	}
301
302	/* this should be in poll */
303	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
304
305reload:
306	ret = -EPIPE;
307	if (sk->sk_shutdown & SEND_SHUTDOWN)
308		goto maybe_error;
309	state = rxrpc_call_state(call);
310	ret = -ESHUTDOWN;
311	if (state >= RXRPC_CALL_COMPLETE)
312		goto maybe_error;
313	ret = -EPROTO;
314	if (state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
315	    state != RXRPC_CALL_SERVER_ACK_REQUEST &&
316	    state != RXRPC_CALL_SERVER_SEND_REPLY) {
317		/* Request phase complete for this client call */
318		trace_rxrpc_abort(call->debug_id, rxrpc_sendmsg_late_send,
319				  call->cid, call->call_id, call->rx_consumed,
320				  0, -EPROTO);
321		goto maybe_error;
322	}
323
324	ret = -EMSGSIZE;
325	if (call->tx_total_len != -1) {
326		if (len - copied > call->tx_total_len)
327			goto maybe_error;
328		if (!more && len - copied != call->tx_total_len)
329			goto maybe_error;
330	}
331
332	txb = call->tx_pending;
333	call->tx_pending = NULL;
334	if (txb)
335		rxrpc_see_txbuf(txb, rxrpc_txbuf_see_send_more);
336
 
337	do {
338		if (!txb) {
339			size_t remain, bufsize, chunk, offset;
 
 
 
 
340
341			_debug("alloc");
342
343			if (!rxrpc_check_tx_space(call, NULL))
344				goto wait_for_space;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
345
346			/* Work out the maximum size of a packet.  Assume that
347			 * the security header is going to be in the padded
348			 * region (enc blocksize), but the trailer is not.
349			 */
350			remain = more ? INT_MAX : msg_data_left(msg);
351			ret = call->conn->security->how_much_data(call, remain,
352								  &bufsize, &chunk, &offset);
353			if (ret < 0)
354				goto maybe_error;
355
356			_debug("SIZE: %zu/%zu @%zu", chunk, bufsize, offset);
357
358			/* create a buffer that we can retain until it's ACK'd */
359			ret = -ENOMEM;
360			txb = rxrpc_alloc_txbuf(call, RXRPC_PACKET_TYPE_DATA,
361						GFP_KERNEL);
362			if (!txb)
363				goto maybe_error;
364
365			txb->offset = offset;
366			txb->space -= offset;
367			txb->space = min_t(size_t, chunk, txb->space);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
368		}
369
370		_debug("append");
 
371
372		/* append next segment of data to the current buffer */
373		if (msg_data_left(msg) > 0) {
374			size_t copy = min_t(size_t, txb->space, msg_data_left(msg));
 
 
 
 
 
375
376			_debug("add %zu", copy);
377			if (!copy_from_iter_full(txb->data + txb->offset, copy,
378						 &msg->msg_iter))
 
379				goto efault;
380			_debug("added");
381			txb->space -= copy;
382			txb->len += copy;
383			txb->offset += copy;
384			copied += copy;
385			if (call->tx_total_len != -1)
386				call->tx_total_len -= copy;
387		}
388
389		/* check for the far side aborting the call or a network error
390		 * occurring */
391		if (rxrpc_call_is_complete(call))
392			goto call_terminated;
393
394		/* add the packet to the send queue if it's now full */
395		if (!txb->space ||
396		    (msg_data_left(msg) == 0 && !more)) {
397			if (msg_data_left(msg) == 0 && !more) {
398				txb->wire.flags |= RXRPC_LAST_PACKET;
399				__set_bit(RXRPC_TXBUF_LAST, &txb->flags);
 
 
 
 
 
 
 
 
 
400			}
401			else if (call->tx_top - call->acks_hard_ack <
 
 
 
 
 
 
 
 
 
402				 call->tx_winsize)
403				txb->wire.flags |= RXRPC_MORE_PACKETS;
404
405			ret = call->security->secure_packet(call, txb);
 
406			if (ret < 0)
407				goto out;
408
409			rxrpc_queue_packet(rx, call, txb, notify_end_tx);
410			txb = NULL;
 
 
 
411		}
412	} while (msg_data_left(msg) > 0);
413
414success:
415	ret = copied;
416	if (rxrpc_call_is_complete(call) &&
417	    call->error < 0)
418		ret = call->error;
419out:
420	call->tx_pending = txb;
421	_leave(" = %d", ret);
422	return ret;
423
424call_terminated:
425	rxrpc_put_txbuf(txb, rxrpc_txbuf_put_send_aborted);
426	_leave(" = %d", call->error);
427	return call->error;
428
429maybe_error:
430	if (copied)
431		goto success;
432	goto out;
433
434efault:
435	ret = -EFAULT;
436	goto out;
437
438wait_for_space:
439	ret = -EAGAIN;
440	if (msg->msg_flags & MSG_DONTWAIT)
441		goto maybe_error;
442	mutex_unlock(&call->user_mutex);
443	*_dropped_lock = true;
444	ret = rxrpc_wait_for_tx_window(rx, call, &timeo,
445				       msg->msg_flags & MSG_WAITALL);
446	if (ret < 0)
447		goto maybe_error;
448	if (call->interruptibility == RXRPC_INTERRUPTIBLE) {
449		if (mutex_lock_interruptible(&call->user_mutex) < 0) {
450			ret = sock_intr_errno(timeo);
451			goto maybe_error;
452		}
453	} else {
454		mutex_lock(&call->user_mutex);
455	}
456	*_dropped_lock = false;
457	goto reload;
458}
459
460/*
461 * extract control messages from the sendmsg() control buffer
462 */
463static int rxrpc_sendmsg_cmsg(struct msghdr *msg, struct rxrpc_send_params *p)
464{
465	struct cmsghdr *cmsg;
466	bool got_user_ID = false;
467	int len;
468
469	if (msg->msg_controllen == 0)
470		return -EINVAL;
471
472	for_each_cmsghdr(cmsg, msg) {
473		if (!CMSG_OK(msg, cmsg))
474			return -EINVAL;
475
476		len = cmsg->cmsg_len - sizeof(struct cmsghdr);
477		_debug("CMSG %d, %d, %d",
478		       cmsg->cmsg_level, cmsg->cmsg_type, len);
479
480		if (cmsg->cmsg_level != SOL_RXRPC)
481			continue;
482
483		switch (cmsg->cmsg_type) {
484		case RXRPC_USER_CALL_ID:
485			if (msg->msg_flags & MSG_CMSG_COMPAT) {
486				if (len != sizeof(u32))
487					return -EINVAL;
488				p->call.user_call_ID = *(u32 *)CMSG_DATA(cmsg);
489			} else {
490				if (len != sizeof(unsigned long))
491					return -EINVAL;
492				p->call.user_call_ID = *(unsigned long *)
493					CMSG_DATA(cmsg);
494			}
495			got_user_ID = true;
496			break;
497
498		case RXRPC_ABORT:
499			if (p->command != RXRPC_CMD_SEND_DATA)
500				return -EINVAL;
501			p->command = RXRPC_CMD_SEND_ABORT;
502			if (len != sizeof(p->abort_code))
503				return -EINVAL;
504			p->abort_code = *(unsigned int *)CMSG_DATA(cmsg);
505			if (p->abort_code == 0)
506				return -EINVAL;
507			break;
508
509		case RXRPC_CHARGE_ACCEPT:
510			if (p->command != RXRPC_CMD_SEND_DATA)
511				return -EINVAL;
512			p->command = RXRPC_CMD_CHARGE_ACCEPT;
513			if (len != 0)
514				return -EINVAL;
515			break;
516
517		case RXRPC_EXCLUSIVE_CALL:
518			p->exclusive = true;
519			if (len != 0)
520				return -EINVAL;
521			break;
522
523		case RXRPC_UPGRADE_SERVICE:
524			p->upgrade = true;
525			if (len != 0)
526				return -EINVAL;
527			break;
528
529		case RXRPC_TX_LENGTH:
530			if (p->call.tx_total_len != -1 || len != sizeof(__s64))
531				return -EINVAL;
532			p->call.tx_total_len = *(__s64 *)CMSG_DATA(cmsg);
533			if (p->call.tx_total_len < 0)
534				return -EINVAL;
535			break;
536
537		case RXRPC_SET_CALL_TIMEOUT:
538			if (len & 3 || len < 4 || len > 12)
539				return -EINVAL;
540			memcpy(&p->call.timeouts, CMSG_DATA(cmsg), len);
541			p->call.nr_timeouts = len / 4;
542			if (p->call.timeouts.hard > INT_MAX / HZ)
543				return -ERANGE;
544			if (p->call.nr_timeouts >= 2 && p->call.timeouts.idle > 60 * 60 * 1000)
545				return -ERANGE;
546			if (p->call.nr_timeouts >= 3 && p->call.timeouts.normal > 60 * 60 * 1000)
547				return -ERANGE;
548			break;
549
550		default:
551			return -EINVAL;
552		}
553	}
554
555	if (!got_user_ID)
556		return -EINVAL;
557	if (p->call.tx_total_len != -1 && p->command != RXRPC_CMD_SEND_DATA)
558		return -EINVAL;
559	_leave(" = 0");
560	return 0;
561}
562
563/*
564 * Create a new client call for sendmsg().
565 * - Called with the socket lock held, which it must release.
566 * - If it returns a call, the call's lock will need releasing by the caller.
567 */
568static struct rxrpc_call *
569rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
570				  struct rxrpc_send_params *p)
571	__releases(&rx->sk.sk_lock.slock)
572	__acquires(&call->user_mutex)
573{
574	struct rxrpc_conn_parameters cp;
575	struct rxrpc_peer *peer;
576	struct rxrpc_call *call;
577	struct key *key;
578
579	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
580
581	_enter("");
582
583	if (!msg->msg_name) {
584		release_sock(&rx->sk);
585		return ERR_PTR(-EDESTADDRREQ);
586	}
587
588	peer = rxrpc_lookup_peer(rx->local, srx, GFP_KERNEL);
589	if (!peer) {
590		release_sock(&rx->sk);
591		return ERR_PTR(-ENOMEM);
592	}
593
594	key = rx->key;
595	if (key && !rx->key->payload.data[0])
596		key = NULL;
597
598	memset(&cp, 0, sizeof(cp));
599	cp.local		= rx->local;
600	cp.peer			= peer;
601	cp.key			= rx->key;
602	cp.security_level	= rx->min_sec_level;
603	cp.exclusive		= rx->exclusive | p->exclusive;
604	cp.upgrade		= p->upgrade;
605	cp.service_id		= srx->srx_service;
606	call = rxrpc_new_client_call(rx, &cp, &p->call, GFP_KERNEL,
607				     atomic_inc_return(&rxrpc_debug_id));
608	/* The socket is now unlocked */
609
610	rxrpc_put_peer(peer, rxrpc_peer_put_application);
611	_leave(" = %p\n", call);
612	return call;
613}
614
615/*
616 * send a message forming part of a client call through an RxRPC socket
617 * - caller holds the socket locked
618 * - the socket may be either a client socket or a server socket
619 */
620int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
621	__releases(&rx->sk.sk_lock.slock)
 
622{
 
623	struct rxrpc_call *call;
624	unsigned long now, j;
625	bool dropped_lock = false;
626	int ret;
627
628	struct rxrpc_send_params p = {
629		.call.tx_total_len	= -1,
630		.call.user_call_ID	= 0,
631		.call.nr_timeouts	= 0,
632		.call.interruptibility	= RXRPC_INTERRUPTIBLE,
633		.abort_code		= 0,
634		.command		= RXRPC_CMD_SEND_DATA,
635		.exclusive		= false,
636		.upgrade		= false,
637	};
638
639	_enter("");
640
641	ret = rxrpc_sendmsg_cmsg(msg, &p);
642	if (ret < 0)
643		goto error_release_sock;
644
645	if (p.command == RXRPC_CMD_CHARGE_ACCEPT) {
646		ret = -EINVAL;
647		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
648			goto error_release_sock;
649		ret = rxrpc_user_charge_accept(rx, p.call.user_call_ID);
650		goto error_release_sock;
651	}
652
653	call = rxrpc_find_call_by_user_ID(rx, p.call.user_call_ID);
654	if (!call) {
655		ret = -EBADSLT;
656		if (p.command != RXRPC_CMD_SEND_DATA)
657			goto error_release_sock;
658		call = rxrpc_new_client_call_for_sendmsg(rx, msg, &p);
659		/* The socket is now unlocked... */
660		if (IS_ERR(call))
661			return PTR_ERR(call);
662		/* ... and we have the call lock. */
663		p.call.nr_timeouts = 0;
664		ret = 0;
665		if (rxrpc_call_is_complete(call))
666			goto out_put_unlock;
667	} else {
668		switch (rxrpc_call_state(call)) {
 
669		case RXRPC_CALL_CLIENT_AWAIT_CONN:
 
670		case RXRPC_CALL_SERVER_SECURING:
671			if (p.command == RXRPC_CMD_SEND_ABORT)
672				break;
673			fallthrough;
674		case RXRPC_CALL_UNINITIALISED:
675		case RXRPC_CALL_SERVER_PREALLOC:
676			rxrpc_put_call(call, rxrpc_call_put_sendmsg);
677			ret = -EBUSY;
678			goto error_release_sock;
679		default:
680			break;
681		}
682
683		ret = mutex_lock_interruptible(&call->user_mutex);
684		release_sock(&rx->sk);
685		if (ret < 0) {
686			ret = -ERESTARTSYS;
687			goto error_put;
688		}
689
690		if (p.call.tx_total_len != -1) {
691			ret = -EINVAL;
692			if (call->tx_total_len != -1 ||
693			    call->tx_pending ||
694			    call->tx_top != 0)
695				goto out_put_unlock;
696			call->tx_total_len = p.call.tx_total_len;
697		}
698	}
699
700	switch (p.call.nr_timeouts) {
701	case 3:
702		j = msecs_to_jiffies(p.call.timeouts.normal);
703		if (p.call.timeouts.normal > 0 && j == 0)
704			j = 1;
705		WRITE_ONCE(call->next_rx_timo, j);
706		fallthrough;
707	case 2:
708		j = msecs_to_jiffies(p.call.timeouts.idle);
709		if (p.call.timeouts.idle > 0 && j == 0)
710			j = 1;
711		WRITE_ONCE(call->next_req_timo, j);
712		fallthrough;
713	case 1:
714		if (p.call.timeouts.hard > 0) {
715			j = p.call.timeouts.hard * HZ;
716			now = jiffies;
717			j += now;
718			WRITE_ONCE(call->expect_term_by, j);
719			rxrpc_reduce_call_timer(call, j, now,
720						rxrpc_timer_set_for_hard);
721		}
722		break;
723	}
724
725	if (rxrpc_call_is_complete(call)) {
 
 
 
 
726		/* it's too late for this call */
727		ret = -ESHUTDOWN;
728	} else if (p.command == RXRPC_CMD_SEND_ABORT) {
729		rxrpc_propose_abort(call, p.abort_code, -ECONNABORTED,
730				    rxrpc_abort_call_sendmsg);
731		ret = 0;
 
 
732	} else if (p.command != RXRPC_CMD_SEND_DATA) {
733		ret = -EINVAL;
 
 
 
 
 
 
 
 
 
734	} else {
735		ret = rxrpc_send_data(rx, call, msg, len, NULL, &dropped_lock);
736	}
737
738out_put_unlock:
739	if (!dropped_lock)
740		mutex_unlock(&call->user_mutex);
741error_put:
742	rxrpc_put_call(call, rxrpc_call_put_sendmsg);
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	bool dropped_lock = false;
769	int ret;
770
771	_enter("{%d},", call->debug_id);
772
773	ASSERTCMP(msg->msg_name, ==, NULL);
774	ASSERTCMP(msg->msg_control, ==, NULL);
775
776	mutex_lock(&call->user_mutex);
777
778	ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len,
779			      notify_end_tx, &dropped_lock);
780	if (ret == -ESHUTDOWN)
 
 
 
 
 
 
 
 
 
781		ret = call->error;
 
 
 
 
 
 
 
 
782
783	if (!dropped_lock)
784		mutex_unlock(&call->user_mutex);
785	_leave(" = %d", ret);
786	return ret;
787}
788EXPORT_SYMBOL(rxrpc_kernel_send_data);
789
790/**
791 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
792 * @sock: The socket the call is on
793 * @call: The call to be aborted
794 * @abort_code: The abort code to stick into the ABORT packet
795 * @error: Local error value
796 * @why: Indication as to why.
797 *
798 * Allow a kernel service to abort a call, if it's still in an abortable state
799 * and return true if the call was aborted, false if it was already complete.
800 */
801bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
802			     u32 abort_code, int error, enum rxrpc_abort_reason why)
803{
804	bool aborted;
805
806	_enter("{%d},%d,%d,%u", call->debug_id, abort_code, error, why);
807
808	mutex_lock(&call->user_mutex);
809	aborted = rxrpc_propose_abort(call, abort_code, error, why);
 
 
 
 
810	mutex_unlock(&call->user_mutex);
811	return aborted;
812}
813EXPORT_SYMBOL(rxrpc_kernel_abort_call);
814
815/**
816 * rxrpc_kernel_set_tx_length - Set the total Tx length on a call
817 * @sock: The socket the call is on
818 * @call: The call to be informed
819 * @tx_total_len: The amount of data to be transmitted for this call
820 *
821 * Allow a kernel service to set the total transmit length on a call.  This
822 * allows buffer-to-packet encrypt-and-copy to be performed.
823 *
824 * This function is primarily for use for setting the reply length since the
825 * request length can be set when beginning the call.
826 */
827void rxrpc_kernel_set_tx_length(struct socket *sock, struct rxrpc_call *call,
828				s64 tx_total_len)
829{
830	WARN_ON(call->tx_total_len != -1);
831	call->tx_total_len = tx_total_len;
832}
833EXPORT_SYMBOL(rxrpc_kernel_set_tx_length);