net/rxrpc/conn_event.c - third_party/linux - Git at Google

 /* connection-level event handling
  *
  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/module.h>
 #include <linux/net.h>
 #include <linux/skbuff.h>
 #include <linux/errqueue.h>
 #include <net/sock.h>
 #include <net/af_rxrpc.h>
 #include <net/ip.h>
 #include "ar-internal.h"

 /*
  * Retransmit terminal ACK or ABORT of the previous call.
  */
 static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
 				       struct sk_buff *skb,
 				       unsigned int channel)
 {
 	struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL;
 	struct rxrpc_channel *chan;
 	struct msghdr msg;
 	struct kvec iov[3];
 	struct {
 		struct rxrpc_wire_header whdr;
 		union {
 			__be32 abort_code;
 			struct rxrpc_ackpacket ack;
 		};
 	} __attribute__((packed)) pkt;
 	struct rxrpc_ackinfo ack_info;
 	size_t len;
 	int ret, ioc;
 	u32 serial, mtu, call_id, padding;

 	_enter("%d", conn->debug_id);

 	chan = &conn->channels[channel];

 	/* If the last call got moved on whilst we were waiting to run, just
 	 * ignore this packet.
 	 */
 	call_id = READ_ONCE(chan->last_call);
 	/* Sync with __rxrpc_disconnect_call() */
 	smp_rmb();
 	if (skb && call_id != sp->hdr.callNumber)
 		return;

 	msg.msg_name	= &conn->params.peer->srx.transport;
 	msg.msg_namelen	= conn->params.peer->srx.transport_len;
 	msg.msg_control	= NULL;
 	msg.msg_controllen = 0;
 	msg.msg_flags	= 0;

 	iov[0].iov_base	= &pkt;
 	iov[0].iov_len	= sizeof(pkt.whdr);
 	iov[1].iov_base	= &padding;
 	iov[1].iov_len	= 3;
 	iov[2].iov_base	= &ack_info;
 	iov[2].iov_len	= sizeof(ack_info);

 	pkt.whdr.epoch		= htonl(conn->proto.epoch);
 	pkt.whdr.cid		= htonl(conn->proto.cid | channel);
 	pkt.whdr.callNumber	= htonl(call_id);
 	pkt.whdr.seq		= 0;
 	pkt.whdr.type		= chan->last_type;
 	pkt.whdr.flags		= conn->out_clientflag;
 	pkt.whdr.userStatus	= 0;
 	pkt.whdr.securityIndex	= conn->security_ix;
 	pkt.whdr._rsvd		= 0;
 	pkt.whdr.serviceId	= htons(conn->service_id);

 	len = sizeof(pkt.whdr);
 	switch (chan->last_type) {
 	case RXRPC_PACKET_TYPE_ABORT:
 		pkt.abort_code	= htonl(chan->last_abort);
 		iov[0].iov_len += sizeof(pkt.abort_code);
 		len += sizeof(pkt.abort_code);
 		ioc = 1;
 		break;

 	case RXRPC_PACKET_TYPE_ACK:
 		mtu = conn->params.peer->if_mtu;
 		mtu -= conn->params.peer->hdrsize;
 		pkt.ack.bufferSpace	= 0;
 		pkt.ack.maxSkew		= htons(skb ? skb->priority : 0);
 		pkt.ack.firstPacket	= htonl(chan->last_seq + 1);
 		pkt.ack.previousPacket	= htonl(chan->last_seq);
 		pkt.ack.serial		= htonl(skb ? sp->hdr.serial : 0);
 		pkt.ack.reason		= skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE;
 		pkt.ack.nAcks		= 0;
 		ack_info.rxMTU		= htonl(rxrpc_rx_mtu);
 		ack_info.maxMTU		= htonl(mtu);
 		ack_info.rwind		= htonl(rxrpc_rx_window_size);
 		ack_info.jumbo_max	= htonl(rxrpc_rx_jumbo_max);
 		pkt.whdr.flags		|= RXRPC_SLOW_START_OK;
 		padding			= 0;
 		iov[0].iov_len += sizeof(pkt.ack);
 		len += sizeof(pkt.ack) + 3 + sizeof(ack_info);
 		ioc = 3;
 		break;

 	default:
 		return;
 	}

 	/* Resync with __rxrpc_disconnect_call() and check that the last call
 	 * didn't get advanced whilst we were filling out the packets.
 	 */
 	smp_rmb();
 	if (READ_ONCE(chan->last_call) != call_id)
 		return;

 	serial = atomic_inc_return(&conn->serial);
 	pkt.whdr.serial = htonl(serial);

 	switch (chan->last_type) {
 	case RXRPC_PACKET_TYPE_ABORT:
 		_proto("Tx ABORT %%%u { %d } [re]", serial, conn->local_abort);
 		break;
 	case RXRPC_PACKET_TYPE_ACK:
 		trace_rxrpc_tx_ack(NULL, serial, chan->last_seq, 0,
 				   RXRPC_ACK_DUPLICATE, 0);
 		_proto("Tx ACK %%%u [re]", serial);
 		break;
 	}

 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
 	conn->params.peer->last_tx_at = ktime_get_real();
 	if (ret < 0)
 		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
 				    rxrpc_tx_fail_call_final_resend);

 	_leave("");
 }

 /*
  * pass a connection-level abort onto all calls on that connection
  */
 static void rxrpc_abort_calls(struct rxrpc_connection *conn,
 			      enum rxrpc_call_completion compl,
 			      u32 abort_code, int error)
 {
 	struct rxrpc_call *call;
 	int i;

 	_enter("{%d},%x", conn->debug_id, abort_code);

 	spin_lock(&conn->channel_lock);

 	for (i = 0; i < RXRPC_MAXCALLS; i++) {
 		call = rcu_dereference_protected(
 			conn->channels[i].call,
 			lockdep_is_held(&conn->channel_lock));
 		if (call) {
 			if (compl == RXRPC_CALL_LOCALLY_ABORTED)
 				trace_rxrpc_abort(call->debug_id,
 						  "CON", call->cid,
 						  call->call_id, 0,
 						  abort_code, error);
 			if (rxrpc_set_call_completion(call, compl,
 						      abort_code, error))
 				rxrpc_notify_socket(call);
 		}
 	}

 	spin_unlock(&conn->channel_lock);
 	_leave("");
 }

 /*
  * generate a connection-level abort
  */
 static int rxrpc_abort_connection(struct rxrpc_connection *conn,
 				  int error, u32 abort_code)
 {
 	struct rxrpc_wire_header whdr;
 	struct msghdr msg;
 	struct kvec iov[2];
 	__be32 word;
 	size_t len;
 	u32 serial;
 	int ret;

 	_enter("%d,,%u,%u", conn->debug_id, error, abort_code);

 	/* generate a connection-level abort */
 	spin_lock_bh(&conn->state_lock);
 	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
 		spin_unlock_bh(&conn->state_lock);
 		_leave(" = 0 [already dead]");
 		return 0;
 	}

 	conn->state = RXRPC_CONN_LOCALLY_ABORTED;
 	spin_unlock_bh(&conn->state_lock);

 	rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, abort_code, error);

 	msg.msg_name	= &conn->params.peer->srx.transport;
 	msg.msg_namelen	= conn->params.peer->srx.transport_len;
 	msg.msg_control	= NULL;
 	msg.msg_controllen = 0;
 	msg.msg_flags	= 0;

 	whdr.epoch	= htonl(conn->proto.epoch);
 	whdr.cid	= htonl(conn->proto.cid);
 	whdr.callNumber	= 0;
 	whdr.seq	= 0;
 	whdr.type	= RXRPC_PACKET_TYPE_ABORT;
 	whdr.flags	= conn->out_clientflag;
 	whdr.userStatus	= 0;
 	whdr.securityIndex = conn->security_ix;
 	whdr._rsvd	= 0;
 	whdr.serviceId	= htons(conn->service_id);

 	word		= htonl(conn->local_abort);

 	iov[0].iov_base	= &whdr;
 	iov[0].iov_len	= sizeof(whdr);
 	iov[1].iov_base	= &word;
 	iov[1].iov_len	= sizeof(word);

 	len = iov[0].iov_len + iov[1].iov_len;

 	serial = atomic_inc_return(&conn->serial);
 	whdr.serial = htonl(serial);
 	_proto("Tx CONN ABORT %%%u { %d }", serial, conn->local_abort);

 	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
 	if (ret < 0) {
 		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
 				    rxrpc_tx_fail_conn_abort);
 		_debug("sendmsg failed: %d", ret);
 		return -EAGAIN;
 	}

 	conn->params.peer->last_tx_at = ktime_get_real();

 	_leave(" = 0");
 	return 0;
 }

 /*
  * mark a call as being on a now-secured channel
  * - must be called with BH's disabled.
  */
 static void rxrpc_call_is_secure(struct rxrpc_call *call)
 {
 	_enter("%p", call);
 	if (call) {
 		write_lock_bh(&call->state_lock);
 		if (call->state == RXRPC_CALL_SERVER_SECURING) {
 			call->state = RXRPC_CALL_SERVER_ACCEPTING;
 			rxrpc_notify_socket(call);
 		}
 		write_unlock_bh(&call->state_lock);
 	}
 }

 /*
  * connection-level Rx packet processor
  */
 static int rxrpc_process_event(struct rxrpc_connection *conn,
 			       struct sk_buff *skb,
 			       u32 *_abort_code)
 {
 	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 	__be32 wtmp;
 	u32 abort_code;
 	int loop, ret;

 	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
 		_leave(" = -ECONNABORTED [%u]", conn->state);
 		return -ECONNABORTED;
 	}

 	_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);

 	switch (sp->hdr.type) {
 	case RXRPC_PACKET_TYPE_DATA:
 	case RXRPC_PACKET_TYPE_ACK:
 		rxrpc_conn_retransmit_call(conn, skb,
 					   sp->hdr.cid & RXRPC_CHANNELMASK);
 		return 0;

 	case RXRPC_PACKET_TYPE_BUSY:
 		/* Just ignore BUSY packets for now. */
 		return 0;

 	case RXRPC_PACKET_TYPE_ABORT:
 		if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
 				  &wtmp, sizeof(wtmp)) < 0) {
 			trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
 					      tracepoint_string("bad_abort"));
 			return -EPROTO;
 		}
 		abort_code = ntohl(wtmp);
 		_proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code);

 		conn->state = RXRPC_CONN_REMOTELY_ABORTED;
 		rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED,
 				  abort_code, -ECONNABORTED);
 		return -ECONNABORTED;

 	case RXRPC_PACKET_TYPE_CHALLENGE:
 		return conn->security->respond_to_challenge(conn, skb,
 							    _abort_code);

 	case RXRPC_PACKET_TYPE_RESPONSE:
 		ret = conn->security->verify_response(conn, skb, _abort_code);
 		if (ret < 0)
 			return ret;

 		ret = conn->security->init_connection_security(conn);
 		if (ret < 0)
 			return ret;

 		ret = conn->security->prime_packet_security(conn);
 		if (ret < 0)
 			return ret;

 		spin_lock(&conn->channel_lock);
 		spin_lock(&conn->state_lock);

 		if (conn->state == RXRPC_CONN_SERVICE_CHALLENGING) {
 			conn->state = RXRPC_CONN_SERVICE;
 			spin_unlock(&conn->state_lock);
 			for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
 				rxrpc_call_is_secure(
 					rcu_dereference_protected(
 						conn->channels[loop].call,
 						lockdep_is_held(&conn->channel_lock)));
 		} else {
 			spin_unlock(&conn->state_lock);
 		}

 		spin_unlock(&conn->channel_lock);
 		return 0;

 	default:
 		trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
 				      tracepoint_string("bad_conn_pkt"));
 		return -EPROTO;
 	}
 }

 /*
  * set up security and issue a challenge
  */
 static void rxrpc_secure_connection(struct rxrpc_connection *conn)
 {
 	u32 abort_code;
 	int ret;

 	_enter("{%d}", conn->debug_id);

 	ASSERT(conn->security_ix != 0);

 	if (!conn->params.key) {
 		_debug("set up security");
 		ret = rxrpc_init_server_conn_security(conn);
 		switch (ret) {
 		case 0:
 			break;
 		case -ENOENT:
 			abort_code = RX_CALL_DEAD;
 			goto abort;
 		default:
 			abort_code = RXKADNOAUTH;
 			goto abort;
 		}
 	}

 	if (conn->security->issue_challenge(conn) < 0) {
 		abort_code = RX_CALL_DEAD;
 		ret = -ENOMEM;
 		goto abort;
 	}

 	_leave("");
 	return;

 abort:
 	_debug("abort %d, %d", ret, abort_code);
 	rxrpc_abort_connection(conn, ret, abort_code);
 	_leave(" [aborted]");
 }

 /*
  * Process delayed final ACKs that we haven't subsumed into a subsequent call.
  */
 static void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn)
 {
 	unsigned long j = jiffies, next_j;
 	unsigned int channel;
 	bool set;

 again:
 	next_j = j + LONG_MAX;
 	set = false;
 	for (channel = 0; channel < RXRPC_MAXCALLS; channel++) {
 		struct rxrpc_channel *chan = &conn->channels[channel];
 		unsigned long ack_at;

 		if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags))
 			continue;

 		smp_rmb(); /* vs rxrpc_disconnect_client_call */
 		ack_at = READ_ONCE(chan->final_ack_at);

 		if (time_before(j, ack_at)) {
 			if (time_before(ack_at, next_j)) {
 				next_j = ack_at;
 				set = true;
 			}
 			continue;
 		}

 		if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel,
 				       &conn->flags))
 			rxrpc_conn_retransmit_call(conn, NULL, channel);
 	}

 	j = jiffies;
 	if (time_before_eq(next_j, j))
 		goto again;
 	if (set)
 		rxrpc_reduce_conn_timer(conn, next_j);
 }

 /*
  * connection-level event processor
  */
 void rxrpc_process_connection(struct work_struct *work)
 {
 	struct rxrpc_connection *conn =
 		container_of(work, struct rxrpc_connection, processor);
 	struct sk_buff *skb;
 	u32 abort_code = RX_PROTOCOL_ERROR;
 	int ret;

 	rxrpc_see_connection(conn);

 	if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
 		rxrpc_secure_connection(conn);

 	/* Process delayed ACKs whose time has come. */
 	if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
 		rxrpc_process_delayed_final_acks(conn);

 	/* go through the conn-level event packets, releasing the ref on this
 	 * connection that each one has when we've finished with it */
 	while ((skb = skb_dequeue(&conn->rx_queue))) {
 		rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
 		ret = rxrpc_process_event(conn, skb, &abort_code);
 		switch (ret) {
 		case -EPROTO:
 		case -EKEYEXPIRED:
 		case -EKEYREJECTED:
 			goto protocol_error;
 		case -ENOMEM:
 		case -EAGAIN:
 			goto requeue_and_leave;
 		case -ECONNABORTED:
 		default:
 			rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
 			break;
 		}
 	}

 out:
 	rxrpc_put_connection(conn);
 	_leave("");
 	return;

 requeue_and_leave:
 	skb_queue_head(&conn->rx_queue, skb);
 	goto out;

 protocol_error:
 	if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
 		goto requeue_and_leave;
 	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
 	goto out;
 }
	/* connection-level event handling
	*
	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	* Written by David Howells (dhowells@redhat.com)
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/module.h>
	#include <linux/net.h>
	#include <linux/skbuff.h>
	#include <linux/errqueue.h>
	#include <net/sock.h>
	#include <net/af_rxrpc.h>
	#include <net/ip.h>
	#include "ar-internal.h"

	/*
	* Retransmit terminal ACK or ABORT of the previous call.
	*/
	static void rxrpc_conn_retransmit_call(struct rxrpc_connection *conn,
	struct sk_buff *skb,
	unsigned int channel)
	{
	struct rxrpc_skb_priv *sp = skb ? rxrpc_skb(skb) : NULL;
	struct rxrpc_channel *chan;
	struct msghdr msg;
	struct kvec iov[3];
	struct {
	struct rxrpc_wire_header whdr;
	union {
	__be32 abort_code;
	struct rxrpc_ackpacket ack;
	};
	} __attribute__((packed)) pkt;
	struct rxrpc_ackinfo ack_info;
	size_t len;
	int ret, ioc;
	u32 serial, mtu, call_id, padding;

	_enter("%d", conn->debug_id);

	chan = &conn->channels[channel];

	/* If the last call got moved on whilst we were waiting to run, just
	* ignore this packet.
	*/
	call_id = READ_ONCE(chan->last_call);
	/* Sync with __rxrpc_disconnect_call() */
	smp_rmb();
	if (skb && call_id != sp->hdr.callNumber)
	return;

	msg.msg_name = &conn->params.peer->srx.transport;
	msg.msg_namelen = conn->params.peer->srx.transport_len;
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_flags = 0;

	iov[0].iov_base = &pkt;
	iov[0].iov_len = sizeof(pkt.whdr);
	iov[1].iov_base = &padding;
	iov[1].iov_len = 3;
	iov[2].iov_base = &ack_info;
	iov[2].iov_len = sizeof(ack_info);

	pkt.whdr.epoch = htonl(conn->proto.epoch);
	pkt.whdr.cid = htonl(conn->proto.cid \| channel);
	pkt.whdr.callNumber = htonl(call_id);
	pkt.whdr.seq = 0;
	pkt.whdr.type = chan->last_type;
	pkt.whdr.flags = conn->out_clientflag;
	pkt.whdr.userStatus = 0;
	pkt.whdr.securityIndex = conn->security_ix;
	pkt.whdr._rsvd = 0;
	pkt.whdr.serviceId = htons(conn->service_id);

	len = sizeof(pkt.whdr);
	switch (chan->last_type) {
	case RXRPC_PACKET_TYPE_ABORT:
	pkt.abort_code = htonl(chan->last_abort);
	iov[0].iov_len += sizeof(pkt.abort_code);
	len += sizeof(pkt.abort_code);
	ioc = 1;
	break;

	case RXRPC_PACKET_TYPE_ACK:
	mtu = conn->params.peer->if_mtu;
	mtu -= conn->params.peer->hdrsize;
	pkt.ack.bufferSpace = 0;
	pkt.ack.maxSkew = htons(skb ? skb->priority : 0);
	pkt.ack.firstPacket = htonl(chan->last_seq + 1);
	pkt.ack.previousPacket = htonl(chan->last_seq);
	pkt.ack.serial = htonl(skb ? sp->hdr.serial : 0);
	pkt.ack.reason = skb ? RXRPC_ACK_DUPLICATE : RXRPC_ACK_IDLE;
	pkt.ack.nAcks = 0;
	ack_info.rxMTU = htonl(rxrpc_rx_mtu);
	ack_info.maxMTU = htonl(mtu);
	ack_info.rwind = htonl(rxrpc_rx_window_size);
	ack_info.jumbo_max = htonl(rxrpc_rx_jumbo_max);
	pkt.whdr.flags \|= RXRPC_SLOW_START_OK;
	padding = 0;
	iov[0].iov_len += sizeof(pkt.ack);
	len += sizeof(pkt.ack) + 3 + sizeof(ack_info);
	ioc = 3;
	break;

	default:
	return;
	}

	/* Resync with __rxrpc_disconnect_call() and check that the last call
	* didn't get advanced whilst we were filling out the packets.
	*/
	smp_rmb();
	if (READ_ONCE(chan->last_call) != call_id)
	return;

	serial = atomic_inc_return(&conn->serial);
	pkt.whdr.serial = htonl(serial);

	switch (chan->last_type) {
	case RXRPC_PACKET_TYPE_ABORT:
	_proto("Tx ABORT %%%u { %d } [re]", serial, conn->local_abort);
	break;
	case RXRPC_PACKET_TYPE_ACK:
	trace_rxrpc_tx_ack(NULL, serial, chan->last_seq, 0,
	RXRPC_ACK_DUPLICATE, 0);
	_proto("Tx ACK %%%u [re]", serial);
	break;
	}

	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, ioc, len);
	conn->params.peer->last_tx_at = ktime_get_real();
	if (ret < 0)
	trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
	rxrpc_tx_fail_call_final_resend);

	_leave("");
	}

	/*
	* pass a connection-level abort onto all calls on that connection
	*/
	static void rxrpc_abort_calls(struct rxrpc_connection *conn,
	enum rxrpc_call_completion compl,
	u32 abort_code, int error)
	{
	struct rxrpc_call *call;
	int i;

	_enter("{%d},%x", conn->debug_id, abort_code);

	spin_lock(&conn->channel_lock);

	for (i = 0; i < RXRPC_MAXCALLS; i++) {
	call = rcu_dereference_protected(
	conn->channels[i].call,
	lockdep_is_held(&conn->channel_lock));
	if (call) {
	if (compl == RXRPC_CALL_LOCALLY_ABORTED)
	trace_rxrpc_abort(call->debug_id,
	"CON", call->cid,
	call->call_id, 0,
	abort_code, error);
	if (rxrpc_set_call_completion(call, compl,
	abort_code, error))
	rxrpc_notify_socket(call);
	}
	}

	spin_unlock(&conn->channel_lock);
	_leave("");
	}

	/*
	* generate a connection-level abort
	*/
	static int rxrpc_abort_connection(struct rxrpc_connection *conn,
	int error, u32 abort_code)
	{
	struct rxrpc_wire_header whdr;
	struct msghdr msg;
	struct kvec iov[2];
	__be32 word;
	size_t len;
	u32 serial;
	int ret;

	_enter("%d,,%u,%u", conn->debug_id, error, abort_code);

	/* generate a connection-level abort */
	spin_lock_bh(&conn->state_lock);
	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
	spin_unlock_bh(&conn->state_lock);
	_leave(" = 0 [already dead]");
	return 0;
	}

	conn->state = RXRPC_CONN_LOCALLY_ABORTED;
	spin_unlock_bh(&conn->state_lock);

	rxrpc_abort_calls(conn, RXRPC_CALL_LOCALLY_ABORTED, abort_code, error);

	msg.msg_name = &conn->params.peer->srx.transport;
	msg.msg_namelen = conn->params.peer->srx.transport_len;
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_flags = 0;

	whdr.epoch = htonl(conn->proto.epoch);
	whdr.cid = htonl(conn->proto.cid);
	whdr.callNumber = 0;
	whdr.seq = 0;
	whdr.type = RXRPC_PACKET_TYPE_ABORT;
	whdr.flags = conn->out_clientflag;
	whdr.userStatus = 0;
	whdr.securityIndex = conn->security_ix;
	whdr._rsvd = 0;
	whdr.serviceId = htons(conn->service_id);

	word = htonl(conn->local_abort);

	iov[0].iov_base = &whdr;
	iov[0].iov_len = sizeof(whdr);
	iov[1].iov_base = &word;
	iov[1].iov_len = sizeof(word);

	len = iov[0].iov_len + iov[1].iov_len;

	serial = atomic_inc_return(&conn->serial);
	whdr.serial = htonl(serial);
	_proto("Tx CONN ABORT %%%u { %d }", serial, conn->local_abort);

	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
	if (ret < 0) {
	trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
	rxrpc_tx_fail_conn_abort);
	_debug("sendmsg failed: %d", ret);
	return -EAGAIN;
	}

	conn->params.peer->last_tx_at = ktime_get_real();

	_leave(" = 0");
	return 0;
	}

	/*
	* mark a call as being on a now-secured channel
	* - must be called with BH's disabled.
	*/
	static void rxrpc_call_is_secure(struct rxrpc_call *call)
	{
	_enter("%p", call);
	if (call) {
	write_lock_bh(&call->state_lock);
	if (call->state == RXRPC_CALL_SERVER_SECURING) {
	call->state = RXRPC_CALL_SERVER_ACCEPTING;
	rxrpc_notify_socket(call);
	}
	write_unlock_bh(&call->state_lock);
	}
	}

	/*
	* connection-level Rx packet processor
	*/
	static int rxrpc_process_event(struct rxrpc_connection *conn,
	struct sk_buff *skb,
	u32 *_abort_code)
	{
	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
	__be32 wtmp;
	u32 abort_code;
	int loop, ret;

	if (conn->state >= RXRPC_CONN_REMOTELY_ABORTED) {
	_leave(" = -ECONNABORTED [%u]", conn->state);
	return -ECONNABORTED;
	}

	_enter("{%d},{%u,%%%u},", conn->debug_id, sp->hdr.type, sp->hdr.serial);

	switch (sp->hdr.type) {
	case RXRPC_PACKET_TYPE_DATA:
	case RXRPC_PACKET_TYPE_ACK:
	rxrpc_conn_retransmit_call(conn, skb,
	sp->hdr.cid & RXRPC_CHANNELMASK);
	return 0;

	case RXRPC_PACKET_TYPE_BUSY:
	/* Just ignore BUSY packets for now. */
	return 0;

	case RXRPC_PACKET_TYPE_ABORT:
	if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
	&wtmp, sizeof(wtmp)) < 0) {
	trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
	tracepoint_string("bad_abort"));
	return -EPROTO;
	}
	abort_code = ntohl(wtmp);
	_proto("Rx ABORT %%%u { ac=%d }", sp->hdr.serial, abort_code);

	conn->state = RXRPC_CONN_REMOTELY_ABORTED;
	rxrpc_abort_calls(conn, RXRPC_CALL_REMOTELY_ABORTED,
	abort_code, -ECONNABORTED);
	return -ECONNABORTED;

	case RXRPC_PACKET_TYPE_CHALLENGE:
	return conn->security->respond_to_challenge(conn, skb,
	_abort_code);

	case RXRPC_PACKET_TYPE_RESPONSE:
	ret = conn->security->verify_response(conn, skb, _abort_code);
	if (ret < 0)
	return ret;

	ret = conn->security->init_connection_security(conn);
	if (ret < 0)
	return ret;

	ret = conn->security->prime_packet_security(conn);
	if (ret < 0)
	return ret;

	spin_lock(&conn->channel_lock);
	spin_lock(&conn->state_lock);

	if (conn->state == RXRPC_CONN_SERVICE_CHALLENGING) {
	conn->state = RXRPC_CONN_SERVICE;
	spin_unlock(&conn->state_lock);
	for (loop = 0; loop < RXRPC_MAXCALLS; loop++)
	rxrpc_call_is_secure(
	rcu_dereference_protected(
	conn->channels[loop].call,
	lockdep_is_held(&conn->channel_lock)));
	} else {
	spin_unlock(&conn->state_lock);
	}

	spin_unlock(&conn->channel_lock);
	return 0;

	default:
	trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
	tracepoint_string("bad_conn_pkt"));
	return -EPROTO;
	}
	}

	/*
	* set up security and issue a challenge
	*/
	static void rxrpc_secure_connection(struct rxrpc_connection *conn)
	{
	u32 abort_code;
	int ret;

	_enter("{%d}", conn->debug_id);

	ASSERT(conn->security_ix != 0);

	if (!conn->params.key) {
	_debug("set up security");
	ret = rxrpc_init_server_conn_security(conn);
	switch (ret) {
	case 0:
	break;
	case -ENOENT:
	abort_code = RX_CALL_DEAD;
	goto abort;
	default:
	abort_code = RXKADNOAUTH;
	goto abort;
	}
	}

	if (conn->security->issue_challenge(conn) < 0) {
	abort_code = RX_CALL_DEAD;
	ret = -ENOMEM;
	goto abort;
	}

	_leave("");
	return;

	abort:
	_debug("abort %d, %d", ret, abort_code);
	rxrpc_abort_connection(conn, ret, abort_code);
	_leave(" [aborted]");
	}

	/*
	* Process delayed final ACKs that we haven't subsumed into a subsequent call.
	*/
	static void rxrpc_process_delayed_final_acks(struct rxrpc_connection *conn)
	{
	unsigned long j = jiffies, next_j;
	unsigned int channel;
	bool set;

	again:
	next_j = j + LONG_MAX;
	set = false;
	for (channel = 0; channel < RXRPC_MAXCALLS; channel++) {
	struct rxrpc_channel *chan = &conn->channels[channel];
	unsigned long ack_at;

	if (!test_bit(RXRPC_CONN_FINAL_ACK_0 + channel, &conn->flags))
	continue;

	smp_rmb(); /* vs rxrpc_disconnect_client_call */
	ack_at = READ_ONCE(chan->final_ack_at);

	if (time_before(j, ack_at)) {
	if (time_before(ack_at, next_j)) {
	next_j = ack_at;
	set = true;
	}
	continue;
	}

	if (test_and_clear_bit(RXRPC_CONN_FINAL_ACK_0 + channel,
	&conn->flags))
	rxrpc_conn_retransmit_call(conn, NULL, channel);
	}

	j = jiffies;
	if (time_before_eq(next_j, j))
	goto again;
	if (set)
	rxrpc_reduce_conn_timer(conn, next_j);
	}

	/*
	* connection-level event processor
	*/
	void rxrpc_process_connection(struct work_struct *work)
	{
	struct rxrpc_connection *conn =
	container_of(work, struct rxrpc_connection, processor);
	struct sk_buff *skb;
	u32 abort_code = RX_PROTOCOL_ERROR;
	int ret;

	rxrpc_see_connection(conn);

	if (test_and_clear_bit(RXRPC_CONN_EV_CHALLENGE, &conn->events))
	rxrpc_secure_connection(conn);

	/* Process delayed ACKs whose time has come. */
	if (conn->flags & RXRPC_CONN_FINAL_ACK_MASK)
	rxrpc_process_delayed_final_acks(conn);

	/* go through the conn-level event packets, releasing the ref on this
	* connection that each one has when we've finished with it */
	while ((skb = skb_dequeue(&conn->rx_queue))) {
	rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
	ret = rxrpc_process_event(conn, skb, &abort_code);
	switch (ret) {
	case -EPROTO:
	case -EKEYEXPIRED:
	case -EKEYREJECTED:
	goto protocol_error;
	case -ENOMEM:
	case -EAGAIN:
	goto requeue_and_leave;
	case -ECONNABORTED:
	default:
	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
	break;
	}
	}

	out:
	rxrpc_put_connection(conn);
	_leave("");
	return;

	requeue_and_leave:
	skb_queue_head(&conn->rx_queue, skb);
	goto out;

	protocol_error:
	if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
	goto requeue_and_leave;
	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
	goto out;
	}