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v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* connection-level event handling
  3 *
  4 * Copyright (C) 2007 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/module.h>
 11#include <linux/net.h>
 12#include <linux/skbuff.h>
 13#include <linux/errqueue.h>
 14#include <net/sock.h>
 15#include <net/af_rxrpc.h>
 16#include <net/ip.h>
 17#include "ar-internal.h"
 18
 19/*
 20 * Retransmit terminal ACK or ABORT of the previous call.
 21 */
 22static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 23				       struct sk_buff *skb,
 24				       unsigned int channel)
 25{
 26	struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL;
 27	struct rxrpc_channel *chan;
 28	struct msghdr msg;
 29	struct kvec iov[3];
 30	struct {
 31		struct rxrpc_wire_header whdr;
 32		union {
 33			__be32 abort_code;
 34			struct rxrpc_ackpacket ack;
 35		};
 36	} __attribute__((packed)) pkt;
 37	struct rxrpc_ackinfo ack_info;
 38	size_t len;
 39	int ret, ioc;
 40	u32 serial, mtu, call_id, padding;
 41
 42	_enter("%d", conn->debug_id);
 43
 44	chan = &conn->channels[channel];
 45
 46	/* If the last call got moved on whilst we were waiting to run, just
 47	 * ignore this packet.
 48	 */
 49	call_id = READ_ONCE(chan->last_call);
 50	/* Sync with __rxrpc_disconnect_call() */
 51	smp_rmb();
 52	if (skb && call_id != sp->hdr.callNumber)
 53		return;
 54
 55	msg.msg_name	= &conn->params.peer->srx.transport;
 56	msg.msg_namelen	= conn->params.peer->srx.transport_len;
 57	msg.msg_control	= NULL;
 58	msg.msg_controllen = 0;
 59	msg.msg_flags	= 0;
 60
 61	iov[0].iov_base	= &pkt;
 62	iov[0].iov_len	= sizeof(pkt.whdr);
 63	iov[1].iov_base	= &padding;
 64	iov[1].iov_len	= 3;
 65	iov[2].iov_base	= &ack_info;
 66	iov[2].iov_len	= sizeof(ack_info);
 67
 68	pkt.whdr.epoch		= htonl(conn->proto.epoch);
 69	pkt.whdr.cid		= htonl(conn->proto.cid | channel);
 70	pkt.whdr.callNumber	= htonl(call_id);
 71	pkt.whdr.seq		= 0;
 72	pkt.whdr.type		= chan->last_type;
 73	pkt.whdr.flags		= conn->out_clientflag;
 74	pkt.whdr.userStatus	= 0;
 75	pkt.whdr.securityIndex	= conn->security_ix;
 76	pkt.whdr._rsvd		= 0;
 77	pkt.whdr.serviceId	= htons(conn->service_id);
 78
 79	len = sizeof(pkt.whdr);
 80	switch (chan->last_type) {
 81	case RXRPC_PACKET_TYPE_ABORT:
 82		pkt.abort_code	= htonl(chan->last_abort);
 83		iov[0].iov_len += sizeof(pkt.abort_code);
 84		len += sizeof(pkt.abort_code);
 85		ioc = 1;
 86		break;
 87
 88	case RXRPC_PACKET_TYPE_ACK:
 89		mtu = conn->params.peer->if_mtu;
 90		mtu -= conn->params.peer->hdrsize;
 91		pkt.ack.bufferSpace	= 0;
 92		pkt.ack.maxSkew		= htons(skb ? skb->priority : 0);
 93		pkt.ack.firstPacket	= htonl(chan->last_seq + 1);
 94		pkt.ack.previousPacket	= htonl(chan->last_seq);
 95		pkt.ack.serial		= htonl(skb ? sp->hdr.serial : 0);
 96		pkt.ack.reason		= skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE;
 97		pkt.ack.nAcks		= 0;
 98		ack_info.rxMTU		= htonl(rxrpc_rx_mtu);
 99		ack_info.maxMTU		= htonl(mtu);
100		ack_info.rwind		= htonl(rxrpc_rx_window_size);
101		ack_info.jumbo_max	= htonl(rxrpc_rx_jumbo_max);
102		pkt.whdr.flags		|= RXRPC_SLOW_START_OK;
103		padding			= 0;
104		iov[0].iov_len += sizeof(pkt.ack);
105		len += sizeof(pkt.ack) + 3 + sizeof(ack_info);
106		ioc = 3;
107		break;
108
109	default:
110		return;
111	}
112
113	/* Resync with __rxrpc_disconnect_call() and check that the last call
114	 * didn't get advanced whilst we were filling out the packets.
115	 */
116	smp_rmb();
117	if (READ_ONCE(chan->last_call) != call_id)
118		return;
119
120	serial = atomic_inc_return(&conn->serial);
121	pkt.whdr.serial = htonl(serial);
122
123	switch (chan->last_type) {
124	case RXRPC_PACKET_TYPE_ABORT:
125		_proto("Tx ABORT %%%u { %d } [re]", serial, conn->abort_code);
126		break;
127	case RXRPC_PACKET_TYPE_ACK:
128		trace_rxrpc_tx_ack(chan->call_debug_id, serial,
129				   ntohl(pkt.ack.firstPacket),
130				   ntohl(pkt.ack.serial),
131				   pkt.ack.reason, 0);
132		_proto("Tx ACK %%%u [re]", serial);
133		break;
134	}
135
136	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
137	conn->params.peer->last_tx_at = ktime_get_seconds();
138	if (ret < 0)
139		trace_rxrpc_tx_fail(chan->call_debug_id, serial, ret,
140				    rxrpc_tx_point_call_final_resend);
141	else
142		trace_rxrpc_tx_packet(chan->call_debug_id, &pkt.whdr,
143				      rxrpc_tx_point_call_final_resend);
144
145	_leave("");
146}
147
148/*
149 * pass a connection-level abort onto all calls on that connection
150 */
151static void rxrpc_abort_calls(struct rxrpc_connection *conn,
152			      enum rxrpc_call_completion compl,
153			      rxrpc_serial_t serial)
154{
155	struct rxrpc_call *call;
156	int i;
157
158	_enter("{%d},%x", conn->debug_id, conn->abort_code);
159
160	spin_lock(&conn->channel_lock);
161
162	for (i = 0; i < RXRPC_MAXCALLS; i++) {
163		call = rcu_dereference_protected(
164			conn->channels[i].call,
165			lockdep_is_held(&conn->channel_lock));
166		if (call) {
167			if (compl == RXRPC_CALL_LOCALLY_ABORTED)
168				trace_rxrpc_abort(call->debug_id,
169						  "CON", call->cid,
170						  call->call_id, 0,
171						  conn->abort_code,
172						  conn->error);
173			else
174				trace_rxrpc_rx_abort(call, serial,
175						     conn->abort_code);
176			rxrpc_set_call_completion(call, compl,
177						  conn->abort_code,
178						  conn->error);
 
179		}
180	}
181
182	spin_unlock(&conn->channel_lock);
183	_leave("");
184}
185
186/*
187 * generate a connection-level abort
188 */
189static int rxrpc_abort_connection(struct rxrpc_connection *conn,
190				  int error, u32 abort_code)
191{
192	struct rxrpc_wire_header whdr;
193	struct msghdr msg;
194	struct kvec iov[2];
195	__be32 word;
196	size_t len;
197	u32 serial;
198	int ret;
199
200	_enter("%d,,%u,%u", conn->debug_id, error, abort_code);
201
202	/* generate a connection-level abort */
203	spin_lock_bh(&conn->state_lock);
204	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
205		spin_unlock_bh(&conn->state_lock);
206		_leave(" = 0 [already dead]");
207		return 0;
208	}
209
210	conn->error = error;
211	conn->abort_code = abort_code;
212	conn->state = RXRPC_CONN_LOCALLY_ABORTED;
213	spin_unlock_bh(&conn->state_lock);
214
215	msg.msg_name	= &conn->params.peer->srx.transport;
216	msg.msg_namelen	= conn->params.peer->srx.transport_len;
217	msg.msg_control	= NULL;
218	msg.msg_controllen = 0;
219	msg.msg_flags	= 0;
220
221	whdr.epoch	= htonl(conn->proto.epoch);
222	whdr.cid	= htonl(conn->proto.cid);
223	whdr.callNumber	= 0;
224	whdr.seq	= 0;
225	whdr.type	= RXRPC_PACKET_TYPE_ABORT;
226	whdr.flags	= conn->out_clientflag;
227	whdr.userStatus	= 0;
228	whdr.securityIndex = conn->security_ix;
229	whdr._rsvd	= 0;
230	whdr.serviceId	= htons(conn->service_id);
231
232	word		= htonl(conn->abort_code);
233
234	iov[0].iov_base	= &whdr;
235	iov[0].iov_len	= sizeof(whdr);
236	iov[1].iov_base	= &word;
237	iov[1].iov_len	= sizeof(word);
238
239	len = iov[0].iov_len + iov[1].iov_len;
240
241	serial = atomic_inc_return(&conn->serial);
242	rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, serial);
243	whdr.serial = htonl(serial);
244	_proto("Tx CONN ABORT %%%u { %d }", serial, conn->abort_code);
245
246	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
247	if (ret < 0) {
248		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
249				    rxrpc_tx_point_conn_abort);
250		_debug("sendmsg failed: %d", ret);
251		return -EAGAIN;
252	}
253
254	trace_rxrpc_tx_packet(conn->debug_id, &whdr, rxrpc_tx_point_conn_abort);
255
256	conn->params.peer->last_tx_at = ktime_get_seconds();
257
258	_leave(" = 0");
259	return 0;
260}
261
262/*
263 * mark a call as being on a now-secured channel
264 * - must be called with BH's disabled.
265 */
266static void rxrpc_call_is_secure(struct rxrpc_call *call)
267{
268	_enter("%p", call);
269	if (call) {
270		write_lock_bh(&call->state_lock);
271		if (call->state == RXRPC_CALL_SERVER_SECURING) {
272			call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
273			rxrpc_notify_socket(call);
274		}
275		write_unlock_bh(&call->state_lock);
276	}
277}
278
279/*
280 * connection-level Rx packet processor
281 */
282static int rxrpc_process_event(struct rxrpc_connection *conn,
283			       struct sk_buff *skb,
284			       u32 *_abort_code)
285{
286	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
287	__be32 wtmp;
288	u32 abort_code;
289	int loop, ret;
290
291	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
292		_leave(" = -ECONNABORTED [%u]", conn->state);
293		return -ECONNABORTED;
294	}
295
296	_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);
297
298	switch (sp->hdr.type) {
299	case RXRPC_PACKET_TYPE_DATA:
300	case RXRPC_PACKET_TYPE_ACK:
301		rxrpc_conn_retransmit_call(conn, skb,
302					   sp->hdr.cid & RXRPC_CHANNELMASK);
303		return 0;
304
305	case RXRPC_PACKET_TYPE_BUSY:
306		/* Just ignore BUSY packets for now. */
307		return 0;
308
309	case RXRPC_PACKET_TYPE_ABORT:
310		if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
311				  &wtmp, sizeof(wtmp)) < 0) {
312			trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
313					      tracepoint_string("bad_abort"));
314			return -EPROTO;
315		}
316		abort_code = ntohl(wtmp);
317		_proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code);
318
319		conn->error = -ECONNABORTED;
320		conn->abort_code = abort_code;
321		conn->state = RXRPC_CONN_REMOTELY_ABORTED;
322		rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED, sp->hdr.serial);
323		return -ECONNABORTED;
324
325	case RXRPC_PACKET_TYPE_CHALLENGE:
326		return conn->security->respond_to_challenge(conn, skb,
327							    _abort_code);
328
329	case RXRPC_PACKET_TYPE_RESPONSE:
330		ret = conn->security->verify_response(conn, skb, _abort_code);
331		if (ret < 0)
332			return ret;
333
334		ret = conn->security->init_connection_security(conn);
335		if (ret < 0)
336			return ret;
337
338		ret = conn->security->prime_packet_security(conn);
339		if (ret < 0)
340			return ret;
341
342		spin_lock(&conn->channel_lock);
343		spin_lock_bh(&conn->state_lock);
344
345		if (conn->state == RXRPC_CONN_SERVICE_CHALLENGING) {
346			conn->state = RXRPC_CONN_SERVICE;
347			spin_unlock_bh(&conn->state_lock);
348			for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
349				rxrpc_call_is_secure(
350					rcu_dereference_protected(
351						conn->channels[loop].call,
352						lockdep_is_held(&conn->channel_lock)));
353		} else {
354			spin_unlock_bh(&conn->state_lock);
355		}
356
357		spin_unlock(&conn->channel_lock);
358		return 0;
359
360	default:
361		trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
362				      tracepoint_string("bad_conn_pkt"));
363		return -EPROTO;
364	}
365}
366
367/*
368 * set up security and issue a challenge
369 */
370static void rxrpc_secure_connection(struct rxrpc_connection *conn)
371{
372	u32 abort_code;
373	int ret;
374
375	_enter("{%d}", conn->debug_id);
376
377	ASSERT(conn->security_ix != 0);
378	ASSERT(conn->server_key);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
379
380	if (conn->security->issue_challenge(conn) < 0) {
381		abort_code = RX_CALL_DEAD;
382		ret = -ENOMEM;
383		goto abort;
384	}
385
386	_leave("");
387	return;
388
389abort:
390	_debug("abort %d, %d", ret, abort_code);
391	rxrpc_abort_connection(conn, ret, abort_code);
392	_leave(" [aborted]");
393}
394
395/*
396 * Process delayed final ACKs that we haven't subsumed into a subsequent call.
397 */
398static void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn)
399{
400	unsigned long j = jiffies, next_j;
401	unsigned int channel;
402	bool set;
403
404again:
405	next_j = j + LONG_MAX;
406	set = false;
407	for (channel = 0; channel < RXRPC_MAXCALLS; channel++) {
408		struct rxrpc_channel *chan = &conn->channels[channel];
409		unsigned long ack_at;
410
411		if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags))
412			continue;
413
414		smp_rmb(); /* vs rxrpc_disconnect_client_call */
415		ack_at = READ_ONCE(chan->final_ack_at);
416
417		if (time_before(j, ack_at)) {
418			if (time_before(ack_at, next_j)) {
419				next_j = ack_at;
420				set = true;
421			}
422			continue;
423		}
424
425		if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel,
426				       &conn->flags))
427			rxrpc_conn_retransmit_call(conn, NULL, channel);
428	}
429
430	j = jiffies;
431	if (time_before_eq(next_j, j))
432		goto again;
433	if (set)
434		rxrpc_reduce_conn_timer(conn, next_j);
435}
436
437/*
438 * connection-level event processor
439 */
440static void rxrpc_do_process_connection(struct rxrpc_connection *conn)
441{
 
 
442	struct sk_buff *skb;
443	u32 abort_code = RX_PROTOCOL_ERROR;
444	int ret;
445
 
 
446	if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
447		rxrpc_secure_connection(conn);
448
449	/* Process delayed ACKs whose time has come. */
450	if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
451		rxrpc_process_delayed_final_acks(conn);
452
453	/* go through the conn-level event packets, releasing the ref on this
454	 * connection that each one has when we've finished with it */
455	while ((skb = skb_dequeue(&conn->rx_queue))) {
456		rxrpc_see_skb(skb, rxrpc_skb_seen);
457		ret = rxrpc_process_event(conn, skb, &abort_code);
458		switch (ret) {
459		case -EPROTO:
460		case -EKEYEXPIRED:
461		case -EKEYREJECTED:
462			goto protocol_error;
463		case -ENOMEM:
464		case -EAGAIN:
465			goto requeue_and_leave;
466		case -ECONNABORTED:
467		default:
468			rxrpc_free_skb(skb, rxrpc_skb_freed);
469			break;
470		}
471	}
472
 
 
 
473	return;
474
475requeue_and_leave:
476	skb_queue_head(&conn->rx_queue, skb);
477	return;
478
479protocol_error:
480	if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
481		goto requeue_and_leave;
482	rxrpc_free_skb(skb, rxrpc_skb_freed);
483	return;
484}
485
486void rxrpc_process_connection(struct work_struct *work)
487{
488	struct rxrpc_connection *conn =
489		container_of(work, struct rxrpc_connection, processor);
490
491	rxrpc_see_connection(conn);
492
493	if (__rxrpc_use_local(conn->params.local)) {
494		rxrpc_do_process_connection(conn);
495		rxrpc_unuse_local(conn->params.local);
496	}
497
498	rxrpc_put_connection(conn);
499	_leave("");
500	return;
501}
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* connection-level event handling
  3 *
  4 * Copyright (C) 2007 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/module.h>
 11#include <linux/net.h>
 12#include <linux/skbuff.h>
 13#include <linux/errqueue.h>
 14#include <net/sock.h>
 15#include <net/af_rxrpc.h>
 16#include <net/ip.h>
 17#include "ar-internal.h"
 18
 19/*
 20 * Retransmit terminal ACK or ABORT of the previous call.
 21 */
 22static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 23				       struct sk_buff *skb,
 24				       unsigned int channel)
 25{
 26	struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL;
 27	struct rxrpc_channel *chan;
 28	struct msghdr msg;
 29	struct kvec iov[3];
 30	struct {
 31		struct rxrpc_wire_header whdr;
 32		union {
 33			__be32 abort_code;
 34			struct rxrpc_ackpacket ack;
 35		};
 36	} __attribute__((packed)) pkt;
 37	struct rxrpc_ackinfo ack_info;
 38	size_t len;
 39	int ret, ioc;
 40	u32 serial, mtu, call_id, padding;
 41
 42	_enter("%d", conn->debug_id);
 43
 44	chan = &conn->channels[channel];
 45
 46	/* If the last call got moved on whilst we were waiting to run, just
 47	 * ignore this packet.
 48	 */
 49	call_id = READ_ONCE(chan->last_call);
 50	/* Sync with __rxrpc_disconnect_call() */
 51	smp_rmb();
 52	if (skb && call_id != sp->hdr.callNumber)
 53		return;
 54
 55	msg.msg_name	= &conn->params.peer->srx.transport;
 56	msg.msg_namelen	= conn->params.peer->srx.transport_len;
 57	msg.msg_control	= NULL;
 58	msg.msg_controllen = 0;
 59	msg.msg_flags	= 0;
 60
 61	iov[0].iov_base	= &pkt;
 62	iov[0].iov_len	= sizeof(pkt.whdr);
 63	iov[1].iov_base	= &padding;
 64	iov[1].iov_len	= 3;
 65	iov[2].iov_base	= &ack_info;
 66	iov[2].iov_len	= sizeof(ack_info);
 67
 68	pkt.whdr.epoch		= htonl(conn->proto.epoch);
 69	pkt.whdr.cid		= htonl(conn->proto.cid | channel);
 70	pkt.whdr.callNumber	= htonl(call_id);
 71	pkt.whdr.seq		= 0;
 72	pkt.whdr.type		= chan->last_type;
 73	pkt.whdr.flags		= conn->out_clientflag;
 74	pkt.whdr.userStatus	= 0;
 75	pkt.whdr.securityIndex	= conn->security_ix;
 76	pkt.whdr._rsvd		= 0;
 77	pkt.whdr.serviceId	= htons(conn->service_id);
 78
 79	len = sizeof(pkt.whdr);
 80	switch (chan->last_type) {
 81	case RXRPC_PACKET_TYPE_ABORT:
 82		pkt.abort_code	= htonl(chan->last_abort);
 83		iov[0].iov_len += sizeof(pkt.abort_code);
 84		len += sizeof(pkt.abort_code);
 85		ioc = 1;
 86		break;
 87
 88	case RXRPC_PACKET_TYPE_ACK:
 89		mtu = conn->params.peer->if_mtu;
 90		mtu -= conn->params.peer->hdrsize;
 91		pkt.ack.bufferSpace	= 0;
 92		pkt.ack.maxSkew		= htons(skb ? skb->priority : 0);
 93		pkt.ack.firstPacket	= htonl(chan->last_seq + 1);
 94		pkt.ack.previousPacket	= htonl(chan->last_seq);
 95		pkt.ack.serial		= htonl(skb ? sp->hdr.serial : 0);
 96		pkt.ack.reason		= skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE;
 97		pkt.ack.nAcks		= 0;
 98		ack_info.rxMTU		= htonl(rxrpc_rx_mtu);
 99		ack_info.maxMTU		= htonl(mtu);
100		ack_info.rwind		= htonl(rxrpc_rx_window_size);
101		ack_info.jumbo_max	= htonl(rxrpc_rx_jumbo_max);
102		pkt.whdr.flags		|= RXRPC_SLOW_START_OK;
103		padding			= 0;
104		iov[0].iov_len += sizeof(pkt.ack);
105		len += sizeof(pkt.ack) + 3 + sizeof(ack_info);
106		ioc = 3;
107		break;
108
109	default:
110		return;
111	}
112
113	/* Resync with __rxrpc_disconnect_call() and check that the last call
114	 * didn't get advanced whilst we were filling out the packets.
115	 */
116	smp_rmb();
117	if (READ_ONCE(chan->last_call) != call_id)
118		return;
119
120	serial = atomic_inc_return(&conn->serial);
121	pkt.whdr.serial = htonl(serial);
122
123	switch (chan->last_type) {
124	case RXRPC_PACKET_TYPE_ABORT:
125		_proto("Tx ABORT %%%u { %d } [re]", serial, conn->abort_code);
126		break;
127	case RXRPC_PACKET_TYPE_ACK:
128		trace_rxrpc_tx_ack(chan->call_debug_id, serial,
129				   ntohl(pkt.ack.firstPacket),
130				   ntohl(pkt.ack.serial),
131				   pkt.ack.reason, 0);
132		_proto("Tx ACK %%%u [re]", serial);
133		break;
134	}
135
136	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
137	conn->params.peer->last_tx_at = ktime_get_seconds();
138	if (ret < 0)
139		trace_rxrpc_tx_fail(chan->call_debug_id, serial, ret,
140				    rxrpc_tx_point_call_final_resend);
141	else
142		trace_rxrpc_tx_packet(chan->call_debug_id, &pkt.whdr,
143				      rxrpc_tx_point_call_final_resend);
144
145	_leave("");
146}
147
148/*
149 * pass a connection-level abort onto all calls on that connection
150 */
151static void rxrpc_abort_calls(struct rxrpc_connection *conn,
152			      enum rxrpc_call_completion compl,
153			      rxrpc_serial_t serial)
154{
155	struct rxrpc_call *call;
156	int i;
157
158	_enter("{%d},%x", conn->debug_id, conn->abort_code);
159
160	spin_lock(&conn->channel_lock);
161
162	for (i = 0; i < RXRPC_MAXCALLS; i++) {
163		call = rcu_dereference_protected(
164			conn->channels[i].call,
165			lockdep_is_held(&conn->channel_lock));
166		if (call) {
167			if (compl == RXRPC_CALL_LOCALLY_ABORTED)
168				trace_rxrpc_abort(call->debug_id,
169						  "CON", call->cid,
170						  call->call_id, 0,
171						  conn->abort_code,
172						  conn->error);
173			else
174				trace_rxrpc_rx_abort(call, serial,
175						     conn->abort_code);
176			if (rxrpc_set_call_completion(call, compl,
177						      conn->abort_code,
178						      conn->error))
179				rxrpc_notify_socket(call);
180		}
181	}
182
183	spin_unlock(&conn->channel_lock);
184	_leave("");
185}
186
187/*
188 * generate a connection-level abort
189 */
190static int rxrpc_abort_connection(struct rxrpc_connection *conn,
191				  int error, u32 abort_code)
192{
193	struct rxrpc_wire_header whdr;
194	struct msghdr msg;
195	struct kvec iov[2];
196	__be32 word;
197	size_t len;
198	u32 serial;
199	int ret;
200
201	_enter("%d,,%u,%u", conn->debug_id, error, abort_code);
202
203	/* generate a connection-level abort */
204	spin_lock_bh(&conn->state_lock);
205	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
206		spin_unlock_bh(&conn->state_lock);
207		_leave(" = 0 [already dead]");
208		return 0;
209	}
210
211	conn->error = error;
212	conn->abort_code = abort_code;
213	conn->state = RXRPC_CONN_LOCALLY_ABORTED;
214	spin_unlock_bh(&conn->state_lock);
215
216	msg.msg_name	= &conn->params.peer->srx.transport;
217	msg.msg_namelen	= conn->params.peer->srx.transport_len;
218	msg.msg_control	= NULL;
219	msg.msg_controllen = 0;
220	msg.msg_flags	= 0;
221
222	whdr.epoch	= htonl(conn->proto.epoch);
223	whdr.cid	= htonl(conn->proto.cid);
224	whdr.callNumber	= 0;
225	whdr.seq	= 0;
226	whdr.type	= RXRPC_PACKET_TYPE_ABORT;
227	whdr.flags	= conn->out_clientflag;
228	whdr.userStatus	= 0;
229	whdr.securityIndex = conn->security_ix;
230	whdr._rsvd	= 0;
231	whdr.serviceId	= htons(conn->service_id);
232
233	word		= htonl(conn->abort_code);
234
235	iov[0].iov_base	= &whdr;
236	iov[0].iov_len	= sizeof(whdr);
237	iov[1].iov_base	= &word;
238	iov[1].iov_len	= sizeof(word);
239
240	len = iov[0].iov_len + iov[1].iov_len;
241
242	serial = atomic_inc_return(&conn->serial);
243	rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, serial);
244	whdr.serial = htonl(serial);
245	_proto("Tx CONN ABORT %%%u { %d }", serial, conn->abort_code);
246
247	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
248	if (ret < 0) {
249		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
250				    rxrpc_tx_point_conn_abort);
251		_debug("sendmsg failed: %d", ret);
252		return -EAGAIN;
253	}
254
255	trace_rxrpc_tx_packet(conn->debug_id, &whdr, rxrpc_tx_point_conn_abort);
256
257	conn->params.peer->last_tx_at = ktime_get_seconds();
258
259	_leave(" = 0");
260	return 0;
261}
262
263/*
264 * mark a call as being on a now-secured channel
265 * - must be called with BH's disabled.
266 */
267static void rxrpc_call_is_secure(struct rxrpc_call *call)
268{
269	_enter("%p", call);
270	if (call) {
271		write_lock_bh(&call->state_lock);
272		if (call->state == RXRPC_CALL_SERVER_SECURING) {
273			call->state = RXRPC_CALL_SERVER_ACCEPTING;
274			rxrpc_notify_socket(call);
275		}
276		write_unlock_bh(&call->state_lock);
277	}
278}
279
280/*
281 * connection-level Rx packet processor
282 */
283static int rxrpc_process_event(struct rxrpc_connection *conn,
284			       struct sk_buff *skb,
285			       u32 *_abort_code)
286{
287	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
288	__be32 wtmp;
289	u32 abort_code;
290	int loop, ret;
291
292	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
293		_leave(" = -ECONNABORTED [%u]", conn->state);
294		return -ECONNABORTED;
295	}
296
297	_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);
298
299	switch (sp->hdr.type) {
300	case RXRPC_PACKET_TYPE_DATA:
301	case RXRPC_PACKET_TYPE_ACK:
302		rxrpc_conn_retransmit_call(conn, skb,
303					   sp->hdr.cid & RXRPC_CHANNELMASK);
304		return 0;
305
306	case RXRPC_PACKET_TYPE_BUSY:
307		/* Just ignore BUSY packets for now. */
308		return 0;
309
310	case RXRPC_PACKET_TYPE_ABORT:
311		if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
312				  &wtmp, sizeof(wtmp)) < 0) {
313			trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
314					      tracepoint_string("bad_abort"));
315			return -EPROTO;
316		}
317		abort_code = ntohl(wtmp);
318		_proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code);
319
320		conn->error = -ECONNABORTED;
321		conn->abort_code = abort_code;
322		conn->state = RXRPC_CONN_REMOTELY_ABORTED;
323		rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED, sp->hdr.serial);
324		return -ECONNABORTED;
325
326	case RXRPC_PACKET_TYPE_CHALLENGE:
327		return conn->security->respond_to_challenge(conn, skb,
328							    _abort_code);
329
330	case RXRPC_PACKET_TYPE_RESPONSE:
331		ret = conn->security->verify_response(conn, skb, _abort_code);
332		if (ret < 0)
333			return ret;
334
335		ret = conn->security->init_connection_security(conn);
336		if (ret < 0)
337			return ret;
338
339		ret = conn->security->prime_packet_security(conn);
340		if (ret < 0)
341			return ret;
342
343		spin_lock(&conn->channel_lock);
344		spin_lock(&conn->state_lock);
345
346		if (conn->state == RXRPC_CONN_SERVICE_CHALLENGING) {
347			conn->state = RXRPC_CONN_SERVICE;
348			spin_unlock(&conn->state_lock);
349			for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
350				rxrpc_call_is_secure(
351					rcu_dereference_protected(
352						conn->channels[loop].call,
353						lockdep_is_held(&conn->channel_lock)));
354		} else {
355			spin_unlock(&conn->state_lock);
356		}
357
358		spin_unlock(&conn->channel_lock);
359		return 0;
360
361	default:
362		trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
363				      tracepoint_string("bad_conn_pkt"));
364		return -EPROTO;
365	}
366}
367
368/*
369 * set up security and issue a challenge
370 */
371static void rxrpc_secure_connection(struct rxrpc_connection *conn)
372{
373	u32 abort_code;
374	int ret;
375
376	_enter("{%d}", conn->debug_id);
377
378	ASSERT(conn->security_ix != 0);
379
380	if (!conn->params.key) {
381		_debug("set up security");
382		ret = rxrpc_init_server_conn_security(conn);
383		switch (ret) {
384		case 0:
385			break;
386		case -ENOENT:
387			abort_code = RX_CALL_DEAD;
388			goto abort;
389		default:
390			abort_code = RXKADNOAUTH;
391			goto abort;
392		}
393	}
394
395	if (conn->security->issue_challenge(conn) < 0) {
396		abort_code = RX_CALL_DEAD;
397		ret = -ENOMEM;
398		goto abort;
399	}
400
401	_leave("");
402	return;
403
404abort:
405	_debug("abort %d, %d", ret, abort_code);
406	rxrpc_abort_connection(conn, ret, abort_code);
407	_leave(" [aborted]");
408}
409
410/*
411 * Process delayed final ACKs that we haven't subsumed into a subsequent call.
412 */
413static void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn)
414{
415	unsigned long j = jiffies, next_j;
416	unsigned int channel;
417	bool set;
418
419again:
420	next_j = j + LONG_MAX;
421	set = false;
422	for (channel = 0; channel < RXRPC_MAXCALLS; channel++) {
423		struct rxrpc_channel *chan = &conn->channels[channel];
424		unsigned long ack_at;
425
426		if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags))
427			continue;
428
429		smp_rmb(); /* vs rxrpc_disconnect_client_call */
430		ack_at = READ_ONCE(chan->final_ack_at);
431
432		if (time_before(j, ack_at)) {
433			if (time_before(ack_at, next_j)) {
434				next_j = ack_at;
435				set = true;
436			}
437			continue;
438		}
439
440		if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel,
441				       &conn->flags))
442			rxrpc_conn_retransmit_call(conn, NULL, channel);
443	}
444
445	j = jiffies;
446	if (time_before_eq(next_j, j))
447		goto again;
448	if (set)
449		rxrpc_reduce_conn_timer(conn, next_j);
450}
451
452/*
453 * connection-level event processor
454 */
455void rxrpc_process_connection(struct work_struct *work)
456{
457	struct rxrpc_connection *conn =
458		container_of(work, struct rxrpc_connection, processor);
459	struct sk_buff *skb;
460	u32 abort_code = RX_PROTOCOL_ERROR;
461	int ret;
462
463	rxrpc_see_connection(conn);
464
465	if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
466		rxrpc_secure_connection(conn);
467
468	/* Process delayed ACKs whose time has come. */
469	if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
470		rxrpc_process_delayed_final_acks(conn);
471
472	/* go through the conn-level event packets, releasing the ref on this
473	 * connection that each one has when we've finished with it */
474	while ((skb = skb_dequeue(&conn->rx_queue))) {
475		rxrpc_see_skb(skb, rxrpc_skb_seen);
476		ret = rxrpc_process_event(conn, skb, &abort_code);
477		switch (ret) {
478		case -EPROTO:
479		case -EKEYEXPIRED:
480		case -EKEYREJECTED:
481			goto protocol_error;
482		case -ENOMEM:
483		case -EAGAIN:
484			goto requeue_and_leave;
485		case -ECONNABORTED:
486		default:
487			rxrpc_free_skb(skb, rxrpc_skb_freed);
488			break;
489		}
490	}
491
492out:
493	rxrpc_put_connection(conn);
494	_leave("");
495	return;
496
497requeue_and_leave:
498	skb_queue_head(&conn->rx_queue, skb);
499	goto out;
500
501protocol_error:
502	if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
503		goto requeue_and_leave;
504	rxrpc_free_skb(skb, rxrpc_skb_freed);
505	goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
506}