1 /* connection.c: Rx connection routines
3 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #include <linux/sched.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <rxrpc/rxrpc.h>
16 #include <rxrpc/transport.h>
17 #include <rxrpc/peer.h>
18 #include <rxrpc/connection.h>
19 #include <rxrpc/call.h>
20 #include <rxrpc/message.h>
21 #include <linux/udp.h>
24 #include <asm/uaccess.h>
27 __RXACCT_DECL(atomic_t rxrpc_connection_count
);
29 LIST_HEAD(rxrpc_conns
);
30 DECLARE_RWSEM(rxrpc_conns_sem
);
31 unsigned long rxrpc_conn_timeout
= 60 * 60;
33 static void rxrpc_conn_do_timeout(struct rxrpc_connection
*conn
);
35 static void __rxrpc_conn_timeout(rxrpc_timer_t
*timer
)
37 struct rxrpc_connection
*conn
=
38 list_entry(timer
, struct rxrpc_connection
, timeout
);
40 _debug("Rx CONN TIMEOUT [%p{u=%d}]", conn
, atomic_read(&conn
->usage
));
42 rxrpc_conn_do_timeout(conn
);
45 static const struct rxrpc_timer_ops rxrpc_conn_timer_ops
= {
46 .timed_out
= __rxrpc_conn_timeout
,
49 /*****************************************************************************/
51 * create a new connection record
53 static inline int __rxrpc_create_connection(struct rxrpc_peer
*peer
,
54 struct rxrpc_connection
**_conn
)
56 struct rxrpc_connection
*conn
;
60 /* allocate and initialise a connection record */
61 conn
= kzalloc(sizeof(struct rxrpc_connection
), GFP_KERNEL
);
67 atomic_set(&conn
->usage
, 1);
69 INIT_LIST_HEAD(&conn
->link
);
70 INIT_LIST_HEAD(&conn
->id_link
);
71 init_waitqueue_head(&conn
->chanwait
);
72 spin_lock_init(&conn
->lock
);
73 rxrpc_timer_init(&conn
->timeout
, &rxrpc_conn_timer_ops
);
75 do_gettimeofday(&conn
->atime
);
76 conn
->mtu_size
= 1024;
78 conn
->trans
= peer
->trans
;
80 __RXACCT(atomic_inc(&rxrpc_connection_count
));
82 _leave(" = 0 (%p)", conn
);
85 } /* end __rxrpc_create_connection() */
87 /*****************************************************************************/
89 * create a new connection record for outgoing connections
91 int rxrpc_create_connection(struct rxrpc_transport
*trans
,
96 struct rxrpc_connection
**_conn
)
98 struct rxrpc_connection
*candidate
, *conn
;
99 struct rxrpc_peer
*peer
;
100 struct list_head
*_p
;
104 _enter("%p{%hu},%u,%hu", trans
, trans
->port
, ntohs(port
), service_id
);
106 /* get a peer record */
107 ret
= rxrpc_peer_lookup(trans
, addr
, &peer
);
109 _leave(" = %d", ret
);
113 /* allocate and initialise a connection record */
114 ret
= __rxrpc_create_connection(peer
, &candidate
);
116 rxrpc_put_peer(peer
);
117 _leave(" = %d", ret
);
121 /* fill in the specific bits */
122 candidate
->addr
.sin_family
= AF_INET
;
123 candidate
->addr
.sin_port
= port
;
124 candidate
->addr
.sin_addr
.s_addr
= addr
;
126 candidate
->in_epoch
= rxrpc_epoch
;
127 candidate
->out_epoch
= rxrpc_epoch
;
128 candidate
->in_clientflag
= 0;
129 candidate
->out_clientflag
= RXRPC_CLIENT_INITIATED
;
130 candidate
->service_id
= htons(service_id
);
132 /* invent a unique connection ID */
133 write_lock(&peer
->conn_idlock
);
136 connid
= htonl(peer
->conn_idcounter
& RXRPC_CIDMASK
);
137 peer
->conn_idcounter
+= RXRPC_MAXCALLS
;
139 list_for_each(_p
, &peer
->conn_idlist
) {
140 conn
= list_entry(_p
, struct rxrpc_connection
, id_link
);
141 if (connid
== conn
->conn_id
)
143 if (connid
> conn
->conn_id
)
147 _debug("selected candidate conn ID %x.%u",
148 ntohl(peer
->addr
.s_addr
), ntohl(connid
));
150 candidate
->conn_id
= connid
;
151 list_add_tail(&candidate
->id_link
, _p
);
153 write_unlock(&peer
->conn_idlock
);
156 candidate
->peer
= peer
;
158 write_lock(&peer
->conn_lock
);
160 /* search the peer's transport graveyard list */
161 spin_lock(&peer
->conn_gylock
);
162 list_for_each(_p
, &peer
->conn_graveyard
) {
163 conn
= list_entry(_p
, struct rxrpc_connection
, link
);
164 if (conn
->addr
.sin_port
== candidate
->addr
.sin_port
&&
165 conn
->security_ix
== candidate
->security_ix
&&
166 conn
->service_id
== candidate
->service_id
&&
167 conn
->in_clientflag
== 0)
168 goto found_in_graveyard
;
170 spin_unlock(&peer
->conn_gylock
);
172 /* pick the new candidate */
173 _debug("created connection: {%08x} [out]", ntohl(candidate
->conn_id
));
174 atomic_inc(&peer
->conn_count
);
179 list_add_tail(&conn
->link
, &peer
->conn_active
);
180 write_unlock(&peer
->conn_lock
);
183 write_lock(&peer
->conn_idlock
);
184 list_del(&candidate
->id_link
);
185 write_unlock(&peer
->conn_idlock
);
187 __RXACCT(atomic_dec(&rxrpc_connection_count
));
191 down_write(&rxrpc_conns_sem
);
192 list_add_tail(&conn
->proc_link
, &rxrpc_conns
);
193 up_write(&rxrpc_conns_sem
);
197 _leave(" = 0 (%p)", conn
);
201 /* handle resurrecting a connection from the graveyard */
203 _debug("resurrecting connection: {%08x} [out]", ntohl(conn
->conn_id
));
204 rxrpc_get_connection(conn
);
205 rxrpc_krxtimod_del_timer(&conn
->timeout
);
206 list_del_init(&conn
->link
);
207 spin_unlock(&peer
->conn_gylock
);
209 } /* end rxrpc_create_connection() */
211 /*****************************************************************************/
213 * lookup the connection for an incoming packet
214 * - create a new connection record for unrecorded incoming connections
216 int rxrpc_connection_lookup(struct rxrpc_peer
*peer
,
217 struct rxrpc_message
*msg
,
218 struct rxrpc_connection
**_conn
)
220 struct rxrpc_connection
*conn
, *candidate
= NULL
;
221 struct list_head
*_p
;
222 struct sk_buff
*pkt
= msg
->pkt
;
224 __be32 x_epoch
, x_connid
;
225 __be16 x_port
, x_servid
;
229 _enter("%p{{%hu}},%u,%hu",
232 ntohs(udp_hdr(pkt
)->source
),
233 ntohs(msg
->hdr
.serviceId
));
235 x_port
= udp_hdr(pkt
)->source
;
236 x_epoch
= msg
->hdr
.epoch
;
237 x_clflag
= msg
->hdr
.flags
& RXRPC_CLIENT_INITIATED
;
238 x_connid
= htonl(ntohl(msg
->hdr
.cid
) & RXRPC_CIDMASK
);
239 x_servid
= msg
->hdr
.serviceId
;
240 x_secix
= msg
->hdr
.securityIndex
;
242 /* [common case] search the transport's active list first */
243 read_lock(&peer
->conn_lock
);
244 list_for_each(_p
, &peer
->conn_active
) {
245 conn
= list_entry(_p
, struct rxrpc_connection
, link
);
246 if (conn
->addr
.sin_port
== x_port
&&
247 conn
->in_epoch
== x_epoch
&&
248 conn
->conn_id
== x_connid
&&
249 conn
->security_ix
== x_secix
&&
250 conn
->service_id
== x_servid
&&
251 conn
->in_clientflag
== x_clflag
)
254 read_unlock(&peer
->conn_lock
);
256 /* [uncommon case] not active
257 * - create a candidate for a new record if an inbound connection
258 * - only examine the graveyard for an outbound connection
261 ret
= __rxrpc_create_connection(peer
, &candidate
);
263 _leave(" = %d", ret
);
267 /* fill in the specifics */
268 candidate
->addr
.sin_family
= AF_INET
;
269 candidate
->addr
.sin_port
= x_port
;
270 candidate
->addr
.sin_addr
.s_addr
= ip_hdr(pkt
)->saddr
;
271 candidate
->in_epoch
= x_epoch
;
272 candidate
->out_epoch
= x_epoch
;
273 candidate
->in_clientflag
= RXRPC_CLIENT_INITIATED
;
274 candidate
->out_clientflag
= 0;
275 candidate
->conn_id
= x_connid
;
276 candidate
->service_id
= x_servid
;
277 candidate
->security_ix
= x_secix
;
280 /* search the active list again, just in case it appeared whilst we
282 write_lock(&peer
->conn_lock
);
283 list_for_each(_p
, &peer
->conn_active
) {
284 conn
= list_entry(_p
, struct rxrpc_connection
, link
);
285 if (conn
->addr
.sin_port
== x_port
&&
286 conn
->in_epoch
== x_epoch
&&
287 conn
->conn_id
== x_connid
&&
288 conn
->security_ix
== x_secix
&&
289 conn
->service_id
== x_servid
&&
290 conn
->in_clientflag
== x_clflag
)
291 goto found_active_second_chance
;
294 /* search the transport's graveyard list */
295 spin_lock(&peer
->conn_gylock
);
296 list_for_each(_p
, &peer
->conn_graveyard
) {
297 conn
= list_entry(_p
, struct rxrpc_connection
, link
);
298 if (conn
->addr
.sin_port
== x_port
&&
299 conn
->in_epoch
== x_epoch
&&
300 conn
->conn_id
== x_connid
&&
301 conn
->security_ix
== x_secix
&&
302 conn
->service_id
== x_servid
&&
303 conn
->in_clientflag
== x_clflag
)
304 goto found_in_graveyard
;
306 spin_unlock(&peer
->conn_gylock
);
308 /* outbound connections aren't created here */
310 write_unlock(&peer
->conn_lock
);
311 _leave(" = -ENOENT");
315 /* we can now add the new candidate to the list */
316 _debug("created connection: {%08x} [in]", ntohl(candidate
->conn_id
));
317 rxrpc_get_peer(peer
);
320 atomic_inc(&peer
->conn_count
);
324 list_add_tail(&conn
->link
, &peer
->conn_active
);
327 write_unlock(&peer
->conn_lock
);
330 write_lock(&peer
->conn_idlock
);
331 list_del(&candidate
->id_link
);
332 write_unlock(&peer
->conn_idlock
);
334 __RXACCT(atomic_dec(&rxrpc_connection_count
));
339 down_write(&rxrpc_conns_sem
);
340 list_add_tail(&conn
->proc_link
, &rxrpc_conns
);
341 up_write(&rxrpc_conns_sem
);
346 _leave(" = 0 (%p)", conn
);
349 /* handle the connection being found in the active list straight off */
351 rxrpc_get_connection(conn
);
352 read_unlock(&peer
->conn_lock
);
355 /* handle resurrecting a connection from the graveyard */
357 _debug("resurrecting connection: {%08x} [in]", ntohl(conn
->conn_id
));
358 rxrpc_get_peer(peer
);
359 rxrpc_get_connection(conn
);
360 rxrpc_krxtimod_del_timer(&conn
->timeout
);
361 list_del_init(&conn
->link
);
362 spin_unlock(&peer
->conn_gylock
);
365 /* handle finding the connection on the second time through the active
367 found_active_second_chance
:
368 rxrpc_get_connection(conn
);
371 } /* end rxrpc_connection_lookup() */
373 /*****************************************************************************/
375 * finish using a connection record
376 * - it will be transferred to the peer's connection graveyard when refcount
379 void rxrpc_put_connection(struct rxrpc_connection
*conn
)
381 struct rxrpc_peer
*peer
;
386 _enter("%p{u=%d p=%hu}",
387 conn
, atomic_read(&conn
->usage
), ntohs(conn
->addr
.sin_port
));
390 spin_lock(&peer
->conn_gylock
);
393 if (atomic_read(&conn
->usage
) <= 0)
396 if (likely(!atomic_dec_and_test(&conn
->usage
))) {
397 spin_unlock(&peer
->conn_gylock
);
402 /* move to graveyard queue */
403 _debug("burying connection: {%08x}", ntohl(conn
->conn_id
));
404 list_move_tail(&conn
->link
, &peer
->conn_graveyard
);
406 rxrpc_krxtimod_add_timer(&conn
->timeout
, rxrpc_conn_timeout
* HZ
);
408 spin_unlock(&peer
->conn_gylock
);
410 rxrpc_put_peer(conn
->peer
);
413 } /* end rxrpc_put_connection() */
415 /*****************************************************************************/
417 * free a connection record
419 static void rxrpc_conn_do_timeout(struct rxrpc_connection
*conn
)
421 struct rxrpc_peer
*peer
;
423 _enter("%p{u=%d p=%hu}",
424 conn
, atomic_read(&conn
->usage
), ntohs(conn
->addr
.sin_port
));
428 if (atomic_read(&conn
->usage
) < 0)
431 /* remove from graveyard if still dead */
432 spin_lock(&peer
->conn_gylock
);
433 if (atomic_read(&conn
->usage
) == 0) {
434 list_del_init(&conn
->link
);
439 spin_unlock(&peer
->conn_gylock
);
443 return; /* resurrected */
446 _debug("--- Destroying Connection %p{%08x} ---",
447 conn
, ntohl(conn
->conn_id
));
449 down_write(&rxrpc_conns_sem
);
450 list_del(&conn
->proc_link
);
451 up_write(&rxrpc_conns_sem
);
453 write_lock(&peer
->conn_idlock
);
454 list_del(&conn
->id_link
);
455 write_unlock(&peer
->conn_idlock
);
457 __RXACCT(atomic_dec(&rxrpc_connection_count
));
460 /* if the graveyard is now empty, wake up anyone waiting for that */
461 if (atomic_dec_and_test(&peer
->conn_count
))
462 wake_up(&peer
->conn_gy_waitq
);
464 _leave(" [destroyed]");
465 } /* end rxrpc_conn_do_timeout() */
467 /*****************************************************************************/
469 * clear all connection records from a peer endpoint
471 void rxrpc_conn_clearall(struct rxrpc_peer
*peer
)
473 DECLARE_WAITQUEUE(myself
, current
);
475 struct rxrpc_connection
*conn
;
480 /* there shouldn't be any active conns remaining */
481 if (!list_empty(&peer
->conn_active
))
484 /* manually timeout all conns in the graveyard */
485 spin_lock(&peer
->conn_gylock
);
486 while (!list_empty(&peer
->conn_graveyard
)) {
487 conn
= list_entry(peer
->conn_graveyard
.next
,
488 struct rxrpc_connection
, link
);
489 err
= rxrpc_krxtimod_del_timer(&conn
->timeout
);
490 spin_unlock(&peer
->conn_gylock
);
493 rxrpc_conn_do_timeout(conn
);
495 spin_lock(&peer
->conn_gylock
);
497 spin_unlock(&peer
->conn_gylock
);
499 /* wait for the the conn graveyard to be completely cleared */
500 set_current_state(TASK_UNINTERRUPTIBLE
);
501 add_wait_queue(&peer
->conn_gy_waitq
, &myself
);
503 while (atomic_read(&peer
->conn_count
) != 0) {
505 set_current_state(TASK_UNINTERRUPTIBLE
);
508 remove_wait_queue(&peer
->conn_gy_waitq
, &myself
);
509 set_current_state(TASK_RUNNING
);
512 } /* end rxrpc_conn_clearall() */
514 /*****************************************************************************/
516 * allocate and prepare a message for sending out through the transport
519 int rxrpc_conn_newmsg(struct rxrpc_connection
*conn
,
520 struct rxrpc_call
*call
,
525 struct rxrpc_message
**_msg
)
527 struct rxrpc_message
*msg
;
530 _enter("%p{%d},%p,%u", conn
, ntohs(conn
->addr
.sin_port
), call
, type
);
533 _leave(" = -EINVAL");
537 msg
= kzalloc(sizeof(struct rxrpc_message
), alloc_flags
);
539 _leave(" = -ENOMEM");
543 atomic_set(&msg
->usage
, 1);
545 INIT_LIST_HEAD(&msg
->link
);
547 msg
->state
= RXRPC_MSG_PREPARED
;
549 msg
->hdr
.epoch
= conn
->out_epoch
;
550 msg
->hdr
.cid
= conn
->conn_id
| (call
? call
->chan_ix
: 0);
551 msg
->hdr
.callNumber
= call
? call
->call_id
: 0;
552 msg
->hdr
.type
= type
;
553 msg
->hdr
.flags
= conn
->out_clientflag
;
554 msg
->hdr
.securityIndex
= conn
->security_ix
;
555 msg
->hdr
.serviceId
= conn
->service_id
;
557 /* generate sequence numbers for data packets */
560 case RXRPC_PACKET_TYPE_DATA
:
561 msg
->seq
= ++call
->snd_seq_count
;
562 msg
->hdr
.seq
= htonl(msg
->seq
);
564 case RXRPC_PACKET_TYPE_ACK
:
565 /* ACK sequence numbers are complicated. The following
567 * - jumbo packet ACKs should have a seq number
568 * - normal ACKs should not
575 msg
->dcount
= dcount
+ 1;
576 msg
->dsize
= sizeof(msg
->hdr
);
577 msg
->data
[0].iov_len
= sizeof(msg
->hdr
);
578 msg
->data
[0].iov_base
= &msg
->hdr
;
580 for (loop
=0; loop
< dcount
; loop
++) {
581 msg
->dsize
+= diov
[loop
].iov_len
;
582 msg
->data
[loop
+1].iov_len
= diov
[loop
].iov_len
;
583 msg
->data
[loop
+1].iov_base
= diov
[loop
].iov_base
;
586 __RXACCT(atomic_inc(&rxrpc_message_count
));
588 _leave(" = 0 (%p) #%d", msg
, atomic_read(&rxrpc_message_count
));
590 } /* end rxrpc_conn_newmsg() */
592 /*****************************************************************************/
596 void __rxrpc_put_message(struct rxrpc_message
*msg
)
600 _enter("%p #%d", msg
, atomic_read(&rxrpc_message_count
));
604 rxrpc_put_connection(msg
->conn
);
606 for (loop
= 0; loop
< 8; loop
++)
607 if (test_bit(loop
, &msg
->dfree
))
608 kfree(msg
->data
[loop
].iov_base
);
610 __RXACCT(atomic_dec(&rxrpc_message_count
));
614 } /* end __rxrpc_put_message() */
616 /*****************************************************************************/
618 * send a message out through the transport endpoint
620 int rxrpc_conn_sendmsg(struct rxrpc_connection
*conn
,
621 struct rxrpc_message
*msg
)
623 struct msghdr msghdr
;
626 _enter("%p{%d}", conn
, ntohs(conn
->addr
.sin_port
));
628 /* fill in some fields in the header */
629 spin_lock(&conn
->lock
);
630 msg
->hdr
.serial
= htonl(++conn
->serial_counter
);
632 spin_unlock(&conn
->lock
);
634 /* set up the message to be transmitted */
635 msghdr
.msg_name
= &conn
->addr
;
636 msghdr
.msg_namelen
= sizeof(conn
->addr
);
637 msghdr
.msg_control
= NULL
;
638 msghdr
.msg_controllen
= 0;
639 msghdr
.msg_flags
= MSG_CONFIRM
| MSG_DONTWAIT
;
641 _net("Sending message type %d of %Zd bytes to %08x:%d",
644 ntohl(conn
->addr
.sin_addr
.s_addr
),
645 ntohs(conn
->addr
.sin_port
));
647 /* send the message */
648 ret
= kernel_sendmsg(conn
->trans
->socket
, &msghdr
,
649 msg
->data
, msg
->dcount
, msg
->dsize
);
651 msg
->state
= RXRPC_MSG_ERROR
;
653 msg
->state
= RXRPC_MSG_SENT
;
656 spin_lock(&conn
->lock
);
657 do_gettimeofday(&conn
->atime
);
658 msg
->stamp
= conn
->atime
;
659 spin_unlock(&conn
->lock
);
662 _leave(" = %d", ret
);
665 } /* end rxrpc_conn_sendmsg() */
667 /*****************************************************************************/
669 * deal with a subsequent call packet
671 int rxrpc_conn_receive_call_packet(struct rxrpc_connection
*conn
,
672 struct rxrpc_call
*call
,
673 struct rxrpc_message
*msg
)
675 struct rxrpc_message
*pmsg
;
676 struct dst_entry
*dst
;
677 struct list_head
*_p
;
681 _enter("%p,%p,%p", conn
, call
, msg
);
684 cix
= ntohl(msg
->hdr
.cid
) & RXRPC_CHANNELMASK
;
686 spin_lock(&conn
->lock
);
687 call
= conn
->channels
[cix
];
689 if (!call
|| call
->call_id
!= msg
->hdr
.callNumber
) {
690 spin_unlock(&conn
->lock
);
691 rxrpc_trans_immediate_abort(conn
->trans
, msg
, -ENOENT
);
695 rxrpc_get_call(call
);
696 spin_unlock(&conn
->lock
);
700 rxrpc_get_call(call
);
703 _proto("Received packet %%%u [%u] on call %hu:%u:%u",
704 ntohl(msg
->hdr
.serial
),
706 ntohs(msg
->hdr
.serviceId
),
707 ntohl(conn
->conn_id
),
708 ntohl(call
->call_id
));
710 call
->pkt_rcv_count
++;
715 dst
->dev
->mtu
- dst
->dev
->hard_header_len
;
717 /* queue on the call in seq order */
718 rxrpc_get_message(msg
);
721 spin_lock(&call
->lock
);
722 list_for_each(_p
, &call
->rcv_receiveq
) {
723 pmsg
= list_entry(_p
, struct rxrpc_message
, link
);
727 list_add_tail(&msg
->link
, _p
);
729 /* reset the activity timeout */
730 call
->flags
|= RXRPC_CALL_RCV_PKT
;
731 mod_timer(&call
->rcv_timeout
,jiffies
+ rxrpc_call_rcv_timeout
* HZ
);
733 spin_unlock(&call
->lock
);
735 rxrpc_krxiod_queue_call(call
);
737 rxrpc_put_call(call
);
739 _leave(" = %d", ret
);
741 } /* end rxrpc_conn_receive_call_packet() */
743 /*****************************************************************************/
745 * handle an ICMP error being applied to a connection
747 void rxrpc_conn_handle_error(struct rxrpc_connection
*conn
,
748 int local
, int errno
)
750 struct rxrpc_call
*calls
[4];
753 _enter("%p{%d},%d", conn
, ntohs(conn
->addr
.sin_port
), errno
);
755 /* get a ref to all my calls in one go */
756 memset(calls
, 0, sizeof(calls
));
757 spin_lock(&conn
->lock
);
759 for (loop
= 3; loop
>= 0; loop
--) {
760 if (conn
->channels
[loop
]) {
761 calls
[loop
] = conn
->channels
[loop
];
762 rxrpc_get_call(calls
[loop
]);
766 spin_unlock(&conn
->lock
);
768 /* now kick them all */
769 for (loop
= 3; loop
>= 0; loop
--) {
771 rxrpc_call_handle_error(calls
[loop
], local
, errno
);
772 rxrpc_put_call(calls
[loop
]);
777 } /* end rxrpc_conn_handle_error() */