Linux Audio

Check our new training course

Embedded Linux training

Mar 31-Apr 8, 2025
Register
Loading...
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);
v4.10.11
 
  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 <net/sock.h>
 19#include <net/af_rxrpc.h>
 20#include "ar-internal.h"
 21
 22enum rxrpc_command {
 23	RXRPC_CMD_SEND_DATA,		/* send data message */
 24	RXRPC_CMD_SEND_ABORT,		/* request abort generation */
 25	RXRPC_CMD_ACCEPT,		/* [server] accept incoming call */
 26	RXRPC_CMD_REJECT_BUSY,		/* [server] reject a call as busy */
 27};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 28
 29/*
 30 * wait for space to appear in the transmit/ACK window
 31 * - caller holds the socket locked
 32 */
 33static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
 34				    struct rxrpc_call *call,
 35				    long *timeo)
 
 36{
 37	DECLARE_WAITQUEUE(myself, current);
 38	int ret;
 39
 40	_enter(",{%u,%u,%u}",
 41	       call->tx_hard_ack, call->tx_top, call->tx_winsize);
 42
 43	add_wait_queue(&call->waitq, &myself);
 44
 45	for (;;) {
 46		set_current_state(TASK_INTERRUPTIBLE);
 47		ret = 0;
 48		if (call->tx_top - call->tx_hard_ack <
 49		    min_t(unsigned int, call->tx_winsize,
 50			  call->cong_cwnd + call->cong_extra))
 51			break;
 52		if (call->state >= RXRPC_CALL_COMPLETE) {
 53			ret = -call->error;
 54			break;
 55		}
 56		if (signal_pending(current)) {
 57			ret = sock_intr_errno(*timeo);
 58			break;
 59		}
 60
 61		trace_rxrpc_transmit(call, rxrpc_transmit_wait);
 62		release_sock(&rx->sk);
 63		*timeo = schedule_timeout(*timeo);
 64		lock_sock(&rx->sk);
 65	}
 66
 67	remove_wait_queue(&call->waitq, &myself);
 68	set_current_state(TASK_RUNNING);
 69	_leave(" = %d", ret);
 70	return ret;
 71}
 72
 73/*
 74 * Schedule an instant Tx resend.
 75 */
 76static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
 77{
 78	spin_lock_bh(&call->lock);
 79
 80	if (call->state < RXRPC_CALL_COMPLETE) {
 81		call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS;
 
 
 82		if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
 83			rxrpc_queue_call(call);
 84	}
 85
 86	spin_unlock_bh(&call->lock);
 87}
 88
 89/*
 90 * Queue a DATA packet for transmission, set the resend timeout and send the
 91 * packet immediately
 
 
 
 
 
 
 
 
 
 
 
 
 92 */
 93static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 94			       bool last)
 
 95{
 96	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 
 97	rxrpc_seq_t seq = sp->hdr.seq;
 98	int ret, ix;
 99	u8 annotation = RXRPC_TX_ANNO_UNACK;
100
101	_net("queue skb %p [%d]", skb, seq);
102
103	ASSERTCMP(seq, ==, call->tx_top + 1);
104
105	if (last)
106		annotation |= RXRPC_TX_ANNO_LAST;
107
108	/* We have to set the timestamp before queueing as the retransmit
109	 * algorithm can see the packet as soon as we queue it.
110	 */
111	skb->tstamp = ktime_get_real();
112
113	ix = seq & RXRPC_RXTX_BUFF_MASK;
114	rxrpc_get_skb(skb, rxrpc_skb_tx_got);
115	call->rxtx_annotations[ix] = annotation;
116	smp_wmb();
117	call->rxtx_buffer[ix] = skb;
118	call->tx_top = seq;
119	if (last)
120		trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
121	else
122		trace_rxrpc_transmit(call, rxrpc_transmit_queue);
123
124	if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
125		_debug("________awaiting reply/ACK__________");
126		write_lock_bh(&call->state_lock);
127		switch (call->state) {
128		case RXRPC_CALL_CLIENT_SEND_REQUEST:
129			call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
 
130			break;
131		case RXRPC_CALL_SERVER_ACK_REQUEST:
132			call->state = RXRPC_CALL_SERVER_SEND_REPLY;
133			call->ack_at = call->expire_at;
 
134			if (call->ackr_reason == RXRPC_ACK_DELAY)
135				call->ackr_reason = 0;
136			__rxrpc_set_timer(call, rxrpc_timer_init_for_send_reply,
137					  ktime_get_real());
138			if (!last)
139				break;
 
140		case RXRPC_CALL_SERVER_SEND_REPLY:
141			call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
 
142			break;
143		default:
144			break;
145		}
146		write_unlock_bh(&call->state_lock);
147	}
148
149	if (seq == 1 && rxrpc_is_client_call(call))
150		rxrpc_expose_client_call(call);
151
152	ret = rxrpc_send_data_packet(call, skb, false);
153	if (ret < 0) {
 
 
 
 
 
 
 
 
154		_debug("need instant resend %d", ret);
155		rxrpc_instant_resend(call, ix);
156	} else {
157		ktime_t now = ktime_get_real(), resend_at;
158
159		resend_at = ktime_add_ms(now, rxrpc_resend_timeout);
160
161		if (ktime_before(resend_at, call->resend_at)) {
162			call->resend_at = resend_at;
163			rxrpc_set_timer(call, rxrpc_timer_set_for_send, now);
164		}
165	}
166
167	rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
168	_leave("");
 
 
169}
170
171/*
172 * send data through a socket
173 * - must be called in process context
174 * - caller holds the socket locked
175 */
176static int rxrpc_send_data(struct rxrpc_sock *rx,
177			   struct rxrpc_call *call,
178			   struct msghdr *msg, size_t len)
 
179{
180	struct rxrpc_skb_priv *sp;
181	struct sk_buff *skb;
182	struct sock *sk = &rx->sk;
183	long timeo;
184	bool more;
185	int ret, copied;
186
187	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
188
189	/* this should be in poll */
190	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
191
192	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
193		return -EPIPE;
194
195	more = msg->msg_flags & MSG_MORE;
196
 
 
 
 
 
 
 
197	skb = call->tx_pending;
198	call->tx_pending = NULL;
199	rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
200
201	copied = 0;
202	do {
203		/* Check to see if there's a ping ACK to reply to. */
204		if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
205			rxrpc_send_ack_packet(call, false);
206
207		if (!skb) {
208			size_t size, chunk, max, space;
209
210			_debug("alloc");
211
212			if (call->tx_top - call->tx_hard_ack >=
213			    min_t(unsigned int, call->tx_winsize,
214				  call->cong_cwnd + call->cong_extra)) {
215				ret = -EAGAIN;
216				if (msg->msg_flags & MSG_DONTWAIT)
217					goto maybe_error;
218				ret = rxrpc_wait_for_tx_window(rx, call,
219							       &timeo);
 
220				if (ret < 0)
221					goto maybe_error;
222			}
223
224			max = RXRPC_JUMBO_DATALEN;
225			max -= call->conn->security_size;
226			max &= ~(call->conn->size_align - 1UL);
227
228			chunk = max;
229			if (chunk > msg_data_left(msg) && !more)
230				chunk = msg_data_left(msg);
231
232			space = chunk + call->conn->size_align;
233			space &= ~(call->conn->size_align - 1UL);
234
235			size = space + call->conn->security_size;
236
237			_debug("SIZE: %zu/%zu/%zu", chunk, space, size);
238
239			/* create a buffer that we can retain until it's ACK'd */
240			skb = sock_alloc_send_skb(
241				sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
242			if (!skb)
243				goto maybe_error;
244
245			rxrpc_new_skb(skb, rxrpc_skb_tx_new);
 
 
246
247			_debug("ALLOC SEND %p", skb);
248
249			ASSERTCMP(skb->mark, ==, 0);
250
251			_debug("HS: %u", call->conn->security_size);
252			skb_reserve(skb, call->conn->security_size);
253			skb->len += call->conn->security_size;
254
255			sp = rxrpc_skb(skb);
256			sp->remain = chunk;
257			if (sp->remain > skb_tailroom(skb))
258				sp->remain = skb_tailroom(skb);
259
260			_net("skb: hr %d, tr %d, hl %d, rm %d",
261			       skb_headroom(skb),
262			       skb_tailroom(skb),
263			       skb_headlen(skb),
264			       sp->remain);
265
266			skb->ip_summed = CHECKSUM_UNNECESSARY;
267		}
268
269		_debug("append");
270		sp = rxrpc_skb(skb);
271
272		/* append next segment of data to the current buffer */
273		if (msg_data_left(msg) > 0) {
274			int copy = skb_tailroom(skb);
275			ASSERTCMP(copy, >, 0);
276			if (copy > msg_data_left(msg))
277				copy = msg_data_left(msg);
278			if (copy > sp->remain)
279				copy = sp->remain;
280
281			_debug("add");
282			ret = skb_add_data(skb, &msg->msg_iter, copy);
283			_debug("added");
284			if (ret < 0)
285				goto efault;
286			sp->remain -= copy;
287			skb->mark += copy;
288			copied += copy;
 
 
289		}
290
291		/* check for the far side aborting the call or a network error
292		 * occurring */
293		if (call->state == RXRPC_CALL_COMPLETE)
294			goto call_terminated;
295
296		/* add the packet to the send queue if it's now full */
297		if (sp->remain <= 0 ||
298		    (msg_data_left(msg) == 0 && !more)) {
299			struct rxrpc_connection *conn = call->conn;
300			uint32_t seq;
301			size_t pad;
302
303			/* pad out if we're using security */
304			if (conn->security_ix) {
305				pad = conn->security_size + skb->mark;
306				pad = conn->size_align - pad;
307				pad &= conn->size_align - 1;
308				_debug("pad %zu", pad);
309				if (pad)
310					memset(skb_put(skb, pad), 0, pad);
311			}
312
313			seq = call->tx_top + 1;
314
315			sp->hdr.seq	= seq;
316			sp->hdr._rsvd	= 0;
317			sp->hdr.flags	= conn->out_clientflag;
318
319			if (msg_data_left(msg) == 0 && !more)
320				sp->hdr.flags |= RXRPC_LAST_PACKET;
321			else if (call->tx_top - call->tx_hard_ack <
322				 call->tx_winsize)
323				sp->hdr.flags |= RXRPC_MORE_PACKETS;
324
325			ret = conn->security->secure_packet(
326				call, skb, skb->mark, skb->head);
327			if (ret < 0)
328				goto out;
329
330			rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
 
 
 
331			skb = NULL;
332		}
333	} while (msg_data_left(msg) > 0);
334
335success:
336	ret = copied;
337out:
338	call->tx_pending = skb;
339	_leave(" = %d", ret);
340	return ret;
341
342call_terminated:
343	rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
344	_leave(" = %d", -call->error);
345	return -call->error;
346
347maybe_error:
348	if (copied)
349		goto success;
350	goto out;
351
352efault:
353	ret = -EFAULT;
354	goto out;
355}
356
357/*
358 * extract control messages from the sendmsg() control buffer
359 */
360static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
361			      unsigned long *user_call_ID,
362			      enum rxrpc_command *command,
363			      u32 *abort_code,
364			      bool *_exclusive)
365{
366	struct cmsghdr *cmsg;
367	bool got_user_ID = false;
368	int len;
369
370	*command = RXRPC_CMD_SEND_DATA;
371
372	if (msg->msg_controllen == 0)
373		return -EINVAL;
374
375	for_each_cmsghdr(cmsg, msg) {
376		if (!CMSG_OK(msg, cmsg))
377			return -EINVAL;
378
379		len = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
380		_debug("CMSG %d, %d, %d",
381		       cmsg->cmsg_level, cmsg->cmsg_type, len);
382
383		if (cmsg->cmsg_level != SOL_RXRPC)
384			continue;
385
386		switch (cmsg->cmsg_type) {
387		case RXRPC_USER_CALL_ID:
388			if (msg->msg_flags & MSG_CMSG_COMPAT) {
389				if (len != sizeof(u32))
390					return -EINVAL;
391				*user_call_ID = *(u32 *) CMSG_DATA(cmsg);
392			} else {
393				if (len != sizeof(unsigned long))
394					return -EINVAL;
395				*user_call_ID = *(unsigned long *)
396					CMSG_DATA(cmsg);
397			}
398			_debug("User Call ID %lx", *user_call_ID);
399			got_user_ID = true;
400			break;
401
402		case RXRPC_ABORT:
403			if (*command != RXRPC_CMD_SEND_DATA)
404				return -EINVAL;
405			*command = RXRPC_CMD_SEND_ABORT;
406			if (len != sizeof(*abort_code))
407				return -EINVAL;
408			*abort_code = *(unsigned int *) CMSG_DATA(cmsg);
409			_debug("Abort %x", *abort_code);
410			if (*abort_code == 0)
411				return -EINVAL;
412			break;
413
414		case RXRPC_ACCEPT:
415			if (*command != RXRPC_CMD_SEND_DATA)
416				return -EINVAL;
417			*command = RXRPC_CMD_ACCEPT;
418			if (len != 0)
419				return -EINVAL;
420			break;
421
422		case RXRPC_EXCLUSIVE_CALL:
423			*_exclusive = true;
 
 
 
 
 
 
424			if (len != 0)
425				return -EINVAL;
426			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
427		default:
428			return -EINVAL;
429		}
430	}
431
432	if (!got_user_ID)
433		return -EINVAL;
 
 
434	_leave(" = 0");
435	return 0;
436}
437
438/*
439 * Create a new client call for sendmsg().
 
 
440 */
441static struct rxrpc_call *
442rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
443				  unsigned long user_call_ID, bool exclusive)
 
 
444{
445	struct rxrpc_conn_parameters cp;
446	struct rxrpc_call *call;
447	struct key *key;
448
449	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
450
451	_enter("");
452
453	if (!msg->msg_name)
 
454		return ERR_PTR(-EDESTADDRREQ);
 
455
456	key = rx->key;
457	if (key && !rx->key->payload.data[0])
458		key = NULL;
459
460	memset(&cp, 0, sizeof(cp));
461	cp.local		= rx->local;
462	cp.key			= rx->key;
463	cp.security_level	= rx->min_sec_level;
464	cp.exclusive		= rx->exclusive | exclusive;
 
465	cp.service_id		= srx->srx_service;
466	call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, GFP_KERNEL);
 
 
467
 
468	_leave(" = %p\n", call);
469	return call;
470}
471
472/*
473 * send a message forming part of a client call through an RxRPC socket
474 * - caller holds the socket locked
475 * - the socket may be either a client socket or a server socket
476 */
477int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 
 
478{
479	enum rxrpc_command cmd;
480	struct rxrpc_call *call;
481	unsigned long user_call_ID = 0;
482	bool exclusive = false;
483	u32 abort_code = 0;
484	int ret;
485
 
 
 
 
 
 
 
 
 
 
 
486	_enter("");
487
488	ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code,
489				 &exclusive);
490	if (ret < 0)
491		return ret;
492
493	if (cmd == RXRPC_CMD_ACCEPT) {
 
494		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
495			return -EINVAL;
496		call = rxrpc_accept_call(rx, user_call_ID, NULL);
497		if (IS_ERR(call))
498			return PTR_ERR(call);
499		rxrpc_put_call(call, rxrpc_call_put);
500		return 0;
501	}
502
503	call = rxrpc_find_call_by_user_ID(rx, user_call_ID);
504	if (!call) {
505		if (cmd != RXRPC_CMD_SEND_DATA)
506			return -EBADSLT;
507		call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
508							 exclusive);
 
509		if (IS_ERR(call))
510			return PTR_ERR(call);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
511	}
512
 
513	_debug("CALL %d USR %lx ST %d on CONN %p",
514	       call->debug_id, call->user_call_ID, call->state, call->conn);
515
516	if (call->state >= RXRPC_CALL_COMPLETE) {
517		/* it's too late for this call */
518		ret = -ESHUTDOWN;
519	} else if (cmd == RXRPC_CMD_SEND_ABORT) {
520		ret = 0;
521		if (rxrpc_abort_call("CMD", call, 0, abort_code, ECONNABORTED))
522			ret = rxrpc_send_abort_packet(call);
523	} else if (cmd != RXRPC_CMD_SEND_DATA) {
524		ret = -EINVAL;
525	} else if (rxrpc_is_client_call(call) &&
526		   call->state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
527		/* request phase complete for this client call */
528		ret = -EPROTO;
529	} else if (rxrpc_is_service_call(call) &&
530		   call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
531		   call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
532		/* Reply phase not begun or not complete for service call. */
533		ret = -EPROTO;
534	} else {
535		ret = rxrpc_send_data(rx, call, msg, len);
536	}
537
 
 
 
538	rxrpc_put_call(call, rxrpc_call_put);
539	_leave(" = %d", ret);
540	return ret;
 
 
 
 
541}
542
543/**
544 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
545 * @sock: The socket the call is on
546 * @call: The call to send data through
547 * @msg: The data to send
548 * @len: The amount of data to send
 
549 *
550 * Allow a kernel service to send data on a call.  The call must be in an state
551 * appropriate to sending data.  No control data should be supplied in @msg,
552 * nor should an address be supplied.  MSG_MORE should be flagged if there's
553 * more data to come, otherwise this data will end the transmission phase.
554 */
555int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
556			   struct msghdr *msg, size_t len)
 
557{
558	int ret;
559
560	_enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
561
562	ASSERTCMP(msg->msg_name, ==, NULL);
563	ASSERTCMP(msg->msg_control, ==, NULL);
564
565	lock_sock(sock->sk);
566
567	_debug("CALL %d USR %lx ST %d on CONN %p",
568	       call->debug_id, call->user_call_ID, call->state, call->conn);
569
570	if (call->state >= RXRPC_CALL_COMPLETE) {
571		ret = -ESHUTDOWN; /* it's too late for this call */
572	} else if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
573		   call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
574		   call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
575		ret = -EPROTO; /* request phase complete for this client call */
576	} else {
577		ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len);
 
 
 
 
 
 
 
 
 
578	}
579
580	release_sock(sock->sk);
581	_leave(" = %d", ret);
582	return ret;
583}
584EXPORT_SYMBOL(rxrpc_kernel_send_data);
585
586/**
587 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
588 * @sock: The socket the call is on
589 * @call: The call to be aborted
590 * @abort_code: The abort code to stick into the ABORT packet
591 * @error: Local error value
592 * @why: 3-char string indicating why.
593 *
594 * Allow a kernel service to abort a call, if it's still in an abortable state.
 
595 */
596void rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
597			     u32 abort_code, int error, const char *why)
598{
 
 
599	_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
600
601	lock_sock(sock->sk);
602
603	if (rxrpc_abort_call(why, call, 0, abort_code, error))
 
604		rxrpc_send_abort_packet(call);
605
606	release_sock(sock->sk);
607	_leave("");
608}
 
609
610EXPORT_SYMBOL(rxrpc_kernel_abort_call);