4 * An implementation of the DCCP protocol
5 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/dccp.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/sched.h>
16 #include <linux/kernel.h>
17 #include <linux/skbuff.h>
18 #include <linux/netdevice.h>
20 #include <linux/if_arp.h>
21 #include <linux/init.h>
22 #include <linux/random.h>
23 #include <linux/slab.h>
24 #include <net/checksum.h>
26 #include <net/inet_sock.h>
30 #include <asm/ioctls.h>
31 #include <linux/spinlock.h>
32 #include <linux/timer.h>
33 #include <linux/delay.h>
34 #include <linux/poll.h>
40 DEFINE_SNMP_STAT(struct dccp_mib
, dccp_statistics
) __read_mostly
;
42 EXPORT_SYMBOL_GPL(dccp_statistics
);
44 struct percpu_counter dccp_orphan_count
;
45 EXPORT_SYMBOL_GPL(dccp_orphan_count
);
47 struct inet_hashinfo dccp_hashinfo
;
48 EXPORT_SYMBOL_GPL(dccp_hashinfo
);
50 /* the maximum queue length for tx in packets. 0 is no limit */
51 int sysctl_dccp_tx_qlen __read_mostly
= 5;
53 void dccp_set_state(struct sock
*sk
, const int state
)
55 const int oldstate
= sk
->sk_state
;
57 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk
), sk
,
58 dccp_state_name(oldstate
), dccp_state_name(state
));
59 WARN_ON(state
== oldstate
);
63 if (oldstate
!= DCCP_OPEN
)
64 DCCP_INC_STATS(DCCP_MIB_CURRESTAB
);
65 /* Client retransmits all Confirm options until entering OPEN */
66 if (oldstate
== DCCP_PARTOPEN
)
67 dccp_feat_list_purge(&dccp_sk(sk
)->dccps_featneg
);
71 if (oldstate
== DCCP_OPEN
|| oldstate
== DCCP_ACTIVE_CLOSEREQ
||
72 oldstate
== DCCP_CLOSING
)
73 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS
);
75 sk
->sk_prot
->unhash(sk
);
76 if (inet_csk(sk
)->icsk_bind_hash
!= NULL
&&
77 !(sk
->sk_userlocks
& SOCK_BINDPORT_LOCK
))
81 if (oldstate
== DCCP_OPEN
)
82 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB
);
85 /* Change state AFTER socket is unhashed to avoid closed
86 * socket sitting in hash tables.
91 EXPORT_SYMBOL_GPL(dccp_set_state
);
93 static void dccp_finish_passive_close(struct sock
*sk
)
95 switch (sk
->sk_state
) {
96 case DCCP_PASSIVE_CLOSE
:
97 /* Node (client or server) has received Close packet. */
98 dccp_send_reset(sk
, DCCP_RESET_CODE_CLOSED
);
99 dccp_set_state(sk
, DCCP_CLOSED
);
101 case DCCP_PASSIVE_CLOSEREQ
:
103 * Client received CloseReq. We set the `active' flag so that
104 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
106 dccp_send_close(sk
, 1);
107 dccp_set_state(sk
, DCCP_CLOSING
);
111 void dccp_done(struct sock
*sk
)
113 dccp_set_state(sk
, DCCP_CLOSED
);
114 dccp_clear_xmit_timers(sk
);
116 sk
->sk_shutdown
= SHUTDOWN_MASK
;
118 if (!sock_flag(sk
, SOCK_DEAD
))
119 sk
->sk_state_change(sk
);
121 inet_csk_destroy_sock(sk
);
124 EXPORT_SYMBOL_GPL(dccp_done
);
126 const char *dccp_packet_name(const int type
)
128 static const char *const dccp_packet_names
[] = {
129 [DCCP_PKT_REQUEST
] = "REQUEST",
130 [DCCP_PKT_RESPONSE
] = "RESPONSE",
131 [DCCP_PKT_DATA
] = "DATA",
132 [DCCP_PKT_ACK
] = "ACK",
133 [DCCP_PKT_DATAACK
] = "DATAACK",
134 [DCCP_PKT_CLOSEREQ
] = "CLOSEREQ",
135 [DCCP_PKT_CLOSE
] = "CLOSE",
136 [DCCP_PKT_RESET
] = "RESET",
137 [DCCP_PKT_SYNC
] = "SYNC",
138 [DCCP_PKT_SYNCACK
] = "SYNCACK",
141 if (type
>= DCCP_NR_PKT_TYPES
)
144 return dccp_packet_names
[type
];
147 EXPORT_SYMBOL_GPL(dccp_packet_name
);
149 const char *dccp_state_name(const int state
)
151 static const char *const dccp_state_names
[] = {
152 [DCCP_OPEN
] = "OPEN",
153 [DCCP_REQUESTING
] = "REQUESTING",
154 [DCCP_PARTOPEN
] = "PARTOPEN",
155 [DCCP_LISTEN
] = "LISTEN",
156 [DCCP_RESPOND
] = "RESPOND",
157 [DCCP_CLOSING
] = "CLOSING",
158 [DCCP_ACTIVE_CLOSEREQ
] = "CLOSEREQ",
159 [DCCP_PASSIVE_CLOSE
] = "PASSIVE_CLOSE",
160 [DCCP_PASSIVE_CLOSEREQ
] = "PASSIVE_CLOSEREQ",
161 [DCCP_TIME_WAIT
] = "TIME_WAIT",
162 [DCCP_CLOSED
] = "CLOSED",
165 if (state
>= DCCP_MAX_STATES
)
166 return "INVALID STATE!";
168 return dccp_state_names
[state
];
171 EXPORT_SYMBOL_GPL(dccp_state_name
);
173 int dccp_init_sock(struct sock
*sk
, const __u8 ctl_sock_initialized
)
175 struct dccp_sock
*dp
= dccp_sk(sk
);
176 struct inet_connection_sock
*icsk
= inet_csk(sk
);
178 icsk
->icsk_rto
= DCCP_TIMEOUT_INIT
;
179 icsk
->icsk_syn_retries
= sysctl_dccp_request_retries
;
180 sk
->sk_state
= DCCP_CLOSED
;
181 sk
->sk_write_space
= dccp_write_space
;
182 icsk
->icsk_sync_mss
= dccp_sync_mss
;
183 dp
->dccps_mss_cache
= 536;
184 dp
->dccps_rate_last
= jiffies
;
185 dp
->dccps_role
= DCCP_ROLE_UNDEFINED
;
186 dp
->dccps_service
= DCCP_SERVICE_CODE_IS_ABSENT
;
187 dp
->dccps_l_ack_ratio
= dp
->dccps_r_ack_ratio
= 1;
189 dccp_init_xmit_timers(sk
);
191 INIT_LIST_HEAD(&dp
->dccps_featneg
);
192 /* control socket doesn't need feat nego */
193 if (likely(ctl_sock_initialized
))
194 return dccp_feat_init(sk
);
198 EXPORT_SYMBOL_GPL(dccp_init_sock
);
200 void dccp_destroy_sock(struct sock
*sk
)
202 struct dccp_sock
*dp
= dccp_sk(sk
);
205 * DCCP doesn't use sk_write_queue, just sk_send_head
206 * for retransmissions
208 if (sk
->sk_send_head
!= NULL
) {
209 kfree_skb(sk
->sk_send_head
);
210 sk
->sk_send_head
= NULL
;
213 /* Clean up a referenced DCCP bind bucket. */
214 if (inet_csk(sk
)->icsk_bind_hash
!= NULL
)
217 kfree(dp
->dccps_service_list
);
218 dp
->dccps_service_list
= NULL
;
220 if (dp
->dccps_hc_rx_ackvec
!= NULL
) {
221 dccp_ackvec_free(dp
->dccps_hc_rx_ackvec
);
222 dp
->dccps_hc_rx_ackvec
= NULL
;
224 ccid_hc_rx_delete(dp
->dccps_hc_rx_ccid
, sk
);
225 ccid_hc_tx_delete(dp
->dccps_hc_tx_ccid
, sk
);
226 dp
->dccps_hc_rx_ccid
= dp
->dccps_hc_tx_ccid
= NULL
;
228 /* clean up feature negotiation state */
229 dccp_feat_list_purge(&dp
->dccps_featneg
);
232 EXPORT_SYMBOL_GPL(dccp_destroy_sock
);
234 static inline int dccp_listen_start(struct sock
*sk
, int backlog
)
236 struct dccp_sock
*dp
= dccp_sk(sk
);
238 dp
->dccps_role
= DCCP_ROLE_LISTEN
;
239 /* do not start to listen if feature negotiation setup fails */
240 if (dccp_feat_finalise_settings(dp
))
242 return inet_csk_listen_start(sk
, backlog
);
245 static inline int dccp_need_reset(int state
)
247 return state
!= DCCP_CLOSED
&& state
!= DCCP_LISTEN
&&
248 state
!= DCCP_REQUESTING
;
251 int dccp_disconnect(struct sock
*sk
, int flags
)
253 struct inet_connection_sock
*icsk
= inet_csk(sk
);
254 struct inet_sock
*inet
= inet_sk(sk
);
256 const int old_state
= sk
->sk_state
;
258 if (old_state
!= DCCP_CLOSED
)
259 dccp_set_state(sk
, DCCP_CLOSED
);
262 * This corresponds to the ABORT function of RFC793, sec. 3.8
263 * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
265 if (old_state
== DCCP_LISTEN
) {
266 inet_csk_listen_stop(sk
);
267 } else if (dccp_need_reset(old_state
)) {
268 dccp_send_reset(sk
, DCCP_RESET_CODE_ABORTED
);
269 sk
->sk_err
= ECONNRESET
;
270 } else if (old_state
== DCCP_REQUESTING
)
271 sk
->sk_err
= ECONNRESET
;
273 dccp_clear_xmit_timers(sk
);
275 __skb_queue_purge(&sk
->sk_receive_queue
);
276 __skb_queue_purge(&sk
->sk_write_queue
);
277 if (sk
->sk_send_head
!= NULL
) {
278 __kfree_skb(sk
->sk_send_head
);
279 sk
->sk_send_head
= NULL
;
282 inet
->inet_dport
= 0;
284 if (!(sk
->sk_userlocks
& SOCK_BINDADDR_LOCK
))
285 inet_reset_saddr(sk
);
288 sock_reset_flag(sk
, SOCK_DONE
);
290 icsk
->icsk_backoff
= 0;
291 inet_csk_delack_init(sk
);
294 WARN_ON(inet
->inet_num
&& !icsk
->icsk_bind_hash
);
296 sk
->sk_error_report(sk
);
300 EXPORT_SYMBOL_GPL(dccp_disconnect
);
303 * Wait for a DCCP event.
305 * Note that we don't need to lock the socket, as the upper poll layers
306 * take care of normal races (between the test and the event) and we don't
307 * go look at any of the socket buffers directly.
309 unsigned int dccp_poll(struct file
*file
, struct socket
*sock
,
313 struct sock
*sk
= sock
->sk
;
315 sock_poll_wait(file
, sk_sleep(sk
), wait
);
316 if (sk
->sk_state
== DCCP_LISTEN
)
317 return inet_csk_listen_poll(sk
);
319 /* Socket is not locked. We are protected from async events
320 by poll logic and correct handling of state changes
321 made by another threads is impossible in any case.
328 if (sk
->sk_shutdown
== SHUTDOWN_MASK
|| sk
->sk_state
== DCCP_CLOSED
)
330 if (sk
->sk_shutdown
& RCV_SHUTDOWN
)
331 mask
|= POLLIN
| POLLRDNORM
| POLLRDHUP
;
334 if ((1 << sk
->sk_state
) & ~(DCCPF_REQUESTING
| DCCPF_RESPOND
)) {
335 if (atomic_read(&sk
->sk_rmem_alloc
) > 0)
336 mask
|= POLLIN
| POLLRDNORM
;
338 if (!(sk
->sk_shutdown
& SEND_SHUTDOWN
)) {
339 if (sk_stream_wspace(sk
) >= sk_stream_min_wspace(sk
)) {
340 mask
|= POLLOUT
| POLLWRNORM
;
341 } else { /* send SIGIO later */
342 set_bit(SOCK_ASYNC_NOSPACE
,
343 &sk
->sk_socket
->flags
);
344 set_bit(SOCK_NOSPACE
, &sk
->sk_socket
->flags
);
346 /* Race breaker. If space is freed after
347 * wspace test but before the flags are set,
348 * IO signal will be lost.
350 if (sk_stream_wspace(sk
) >= sk_stream_min_wspace(sk
))
351 mask
|= POLLOUT
| POLLWRNORM
;
358 EXPORT_SYMBOL_GPL(dccp_poll
);
360 int dccp_ioctl(struct sock
*sk
, int cmd
, unsigned long arg
)
366 if (sk
->sk_state
== DCCP_LISTEN
)
372 unsigned long amount
= 0;
374 skb
= skb_peek(&sk
->sk_receive_queue
);
377 * We will only return the amount of this packet since
378 * that is all that will be read.
382 rc
= put_user(amount
, (int __user
*)arg
);
394 EXPORT_SYMBOL_GPL(dccp_ioctl
);
396 static int dccp_setsockopt_service(struct sock
*sk
, const __be32 service
,
397 char __user
*optval
, unsigned int optlen
)
399 struct dccp_sock
*dp
= dccp_sk(sk
);
400 struct dccp_service_list
*sl
= NULL
;
402 if (service
== DCCP_SERVICE_INVALID_VALUE
||
403 optlen
> DCCP_SERVICE_LIST_MAX_LEN
* sizeof(u32
))
406 if (optlen
> sizeof(service
)) {
407 sl
= kmalloc(optlen
, GFP_KERNEL
);
411 sl
->dccpsl_nr
= optlen
/ sizeof(u32
) - 1;
412 if (copy_from_user(sl
->dccpsl_list
,
413 optval
+ sizeof(service
),
414 optlen
- sizeof(service
)) ||
415 dccp_list_has_service(sl
, DCCP_SERVICE_INVALID_VALUE
)) {
422 dp
->dccps_service
= service
;
424 kfree(dp
->dccps_service_list
);
426 dp
->dccps_service_list
= sl
;
431 static int dccp_setsockopt_cscov(struct sock
*sk
, int cscov
, bool rx
)
436 if (cscov
< 0 || cscov
> 15)
439 * Populate a list of permissible values, in the range cscov...15. This
440 * is necessary since feature negotiation of single values only works if
441 * both sides incidentally choose the same value. Since the list starts
442 * lowest-value first, negotiation will pick the smallest shared value.
448 list
= kmalloc(len
, GFP_KERNEL
);
452 for (i
= 0; i
< len
; i
++)
455 rc
= dccp_feat_register_sp(sk
, DCCPF_MIN_CSUM_COVER
, rx
, list
, len
);
459 dccp_sk(sk
)->dccps_pcrlen
= cscov
;
461 dccp_sk(sk
)->dccps_pcslen
= cscov
;
467 static int dccp_setsockopt_ccid(struct sock
*sk
, int type
,
468 char __user
*optval
, unsigned int optlen
)
473 if (optlen
< 1 || optlen
> DCCP_FEAT_MAX_SP_VALS
)
476 val
= kmalloc(optlen
, GFP_KERNEL
);
480 if (copy_from_user(val
, optval
, optlen
)) {
486 if (type
== DCCP_SOCKOPT_TX_CCID
|| type
== DCCP_SOCKOPT_CCID
)
487 rc
= dccp_feat_register_sp(sk
, DCCPF_CCID
, 1, val
, optlen
);
489 if (!rc
&& (type
== DCCP_SOCKOPT_RX_CCID
|| type
== DCCP_SOCKOPT_CCID
))
490 rc
= dccp_feat_register_sp(sk
, DCCPF_CCID
, 0, val
, optlen
);
497 static int do_dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
498 char __user
*optval
, unsigned int optlen
)
500 struct dccp_sock
*dp
= dccp_sk(sk
);
504 case DCCP_SOCKOPT_PACKET_SIZE
:
505 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
507 case DCCP_SOCKOPT_CHANGE_L
:
508 case DCCP_SOCKOPT_CHANGE_R
:
509 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
511 case DCCP_SOCKOPT_CCID
:
512 case DCCP_SOCKOPT_RX_CCID
:
513 case DCCP_SOCKOPT_TX_CCID
:
514 return dccp_setsockopt_ccid(sk
, optname
, optval
, optlen
);
517 if (optlen
< (int)sizeof(int))
520 if (get_user(val
, (int __user
*)optval
))
523 if (optname
== DCCP_SOCKOPT_SERVICE
)
524 return dccp_setsockopt_service(sk
, val
, optval
, optlen
);
528 case DCCP_SOCKOPT_SERVER_TIMEWAIT
:
529 if (dp
->dccps_role
!= DCCP_ROLE_SERVER
)
532 dp
->dccps_server_timewait
= (val
!= 0);
534 case DCCP_SOCKOPT_SEND_CSCOV
:
535 err
= dccp_setsockopt_cscov(sk
, val
, false);
537 case DCCP_SOCKOPT_RECV_CSCOV
:
538 err
= dccp_setsockopt_cscov(sk
, val
, true);
549 int dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
550 char __user
*optval
, unsigned int optlen
)
552 if (level
!= SOL_DCCP
)
553 return inet_csk(sk
)->icsk_af_ops
->setsockopt(sk
, level
,
556 return do_dccp_setsockopt(sk
, level
, optname
, optval
, optlen
);
559 EXPORT_SYMBOL_GPL(dccp_setsockopt
);
562 int compat_dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
563 char __user
*optval
, unsigned int optlen
)
565 if (level
!= SOL_DCCP
)
566 return inet_csk_compat_setsockopt(sk
, level
, optname
,
568 return do_dccp_setsockopt(sk
, level
, optname
, optval
, optlen
);
571 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt
);
574 static int dccp_getsockopt_service(struct sock
*sk
, int len
,
575 __be32 __user
*optval
,
578 const struct dccp_sock
*dp
= dccp_sk(sk
);
579 const struct dccp_service_list
*sl
;
580 int err
= -ENOENT
, slen
= 0, total_len
= sizeof(u32
);
583 if ((sl
= dp
->dccps_service_list
) != NULL
) {
584 slen
= sl
->dccpsl_nr
* sizeof(u32
);
593 if (put_user(total_len
, optlen
) ||
594 put_user(dp
->dccps_service
, optval
) ||
595 (sl
!= NULL
&& copy_to_user(optval
+ 1, sl
->dccpsl_list
, slen
)))
602 static int do_dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
603 char __user
*optval
, int __user
*optlen
)
605 struct dccp_sock
*dp
;
608 if (get_user(len
, optlen
))
611 if (len
< (int)sizeof(int))
617 case DCCP_SOCKOPT_PACKET_SIZE
:
618 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
620 case DCCP_SOCKOPT_SERVICE
:
621 return dccp_getsockopt_service(sk
, len
,
622 (__be32 __user
*)optval
, optlen
);
623 case DCCP_SOCKOPT_GET_CUR_MPS
:
624 val
= dp
->dccps_mss_cache
;
626 case DCCP_SOCKOPT_AVAILABLE_CCIDS
:
627 return ccid_getsockopt_builtin_ccids(sk
, len
, optval
, optlen
);
628 case DCCP_SOCKOPT_TX_CCID
:
629 val
= ccid_get_current_tx_ccid(dp
);
633 case DCCP_SOCKOPT_RX_CCID
:
634 val
= ccid_get_current_rx_ccid(dp
);
638 case DCCP_SOCKOPT_SERVER_TIMEWAIT
:
639 val
= dp
->dccps_server_timewait
;
641 case DCCP_SOCKOPT_SEND_CSCOV
:
642 val
= dp
->dccps_pcslen
;
644 case DCCP_SOCKOPT_RECV_CSCOV
:
645 val
= dp
->dccps_pcrlen
;
648 return ccid_hc_rx_getsockopt(dp
->dccps_hc_rx_ccid
, sk
, optname
,
649 len
, (u32 __user
*)optval
, optlen
);
651 return ccid_hc_tx_getsockopt(dp
->dccps_hc_tx_ccid
, sk
, optname
,
652 len
, (u32 __user
*)optval
, optlen
);
658 if (put_user(len
, optlen
) || copy_to_user(optval
, &val
, len
))
664 int dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
665 char __user
*optval
, int __user
*optlen
)
667 if (level
!= SOL_DCCP
)
668 return inet_csk(sk
)->icsk_af_ops
->getsockopt(sk
, level
,
671 return do_dccp_getsockopt(sk
, level
, optname
, optval
, optlen
);
674 EXPORT_SYMBOL_GPL(dccp_getsockopt
);
677 int compat_dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
678 char __user
*optval
, int __user
*optlen
)
680 if (level
!= SOL_DCCP
)
681 return inet_csk_compat_getsockopt(sk
, level
, optname
,
683 return do_dccp_getsockopt(sk
, level
, optname
, optval
, optlen
);
686 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt
);
689 int dccp_sendmsg(struct kiocb
*iocb
, struct sock
*sk
, struct msghdr
*msg
,
692 const struct dccp_sock
*dp
= dccp_sk(sk
);
693 const int flags
= msg
->msg_flags
;
694 const int noblock
= flags
& MSG_DONTWAIT
;
699 if (len
> dp
->dccps_mss_cache
)
704 if (sysctl_dccp_tx_qlen
&&
705 (sk
->sk_write_queue
.qlen
>= sysctl_dccp_tx_qlen
)) {
710 timeo
= sock_sndtimeo(sk
, noblock
);
713 * We have to use sk_stream_wait_connect here to set sk_write_pending,
714 * so that the trick in dccp_rcv_request_sent_state_process.
716 /* Wait for a connection to finish. */
717 if ((1 << sk
->sk_state
) & ~(DCCPF_OPEN
| DCCPF_PARTOPEN
))
718 if ((rc
= sk_stream_wait_connect(sk
, &timeo
)) != 0)
721 size
= sk
->sk_prot
->max_header
+ len
;
723 skb
= sock_alloc_send_skb(sk
, size
, noblock
, &rc
);
728 skb_reserve(skb
, sk
->sk_prot
->max_header
);
729 rc
= memcpy_fromiovec(skb_put(skb
, len
), msg
->msg_iov
, len
);
733 skb_queue_tail(&sk
->sk_write_queue
, skb
);
734 dccp_write_xmit(sk
,0);
743 EXPORT_SYMBOL_GPL(dccp_sendmsg
);
745 int dccp_recvmsg(struct kiocb
*iocb
, struct sock
*sk
, struct msghdr
*msg
,
746 size_t len
, int nonblock
, int flags
, int *addr_len
)
748 const struct dccp_hdr
*dh
;
753 if (sk
->sk_state
== DCCP_LISTEN
) {
758 timeo
= sock_rcvtimeo(sk
, nonblock
);
761 struct sk_buff
*skb
= skb_peek(&sk
->sk_receive_queue
);
764 goto verify_sock_status
;
768 switch (dh
->dccph_type
) {
770 case DCCP_PKT_DATAACK
:
774 case DCCP_PKT_CLOSEREQ
:
775 if (!(flags
& MSG_PEEK
))
776 dccp_finish_passive_close(sk
);
779 dccp_pr_debug("found fin (%s) ok!\n",
780 dccp_packet_name(dh
->dccph_type
));
784 dccp_pr_debug("packet_type=%s\n",
785 dccp_packet_name(dh
->dccph_type
));
786 sk_eat_skb(sk
, skb
, 0);
789 if (sock_flag(sk
, SOCK_DONE
)) {
795 len
= sock_error(sk
);
799 if (sk
->sk_shutdown
& RCV_SHUTDOWN
) {
804 if (sk
->sk_state
== DCCP_CLOSED
) {
805 if (!sock_flag(sk
, SOCK_DONE
)) {
806 /* This occurs when user tries to read
807 * from never connected socket.
821 if (signal_pending(current
)) {
822 len
= sock_intr_errno(timeo
);
826 sk_wait_data(sk
, &timeo
);
831 else if (len
< skb
->len
)
832 msg
->msg_flags
|= MSG_TRUNC
;
834 if (skb_copy_datagram_iovec(skb
, 0, msg
->msg_iov
, len
)) {
835 /* Exception. Bailout! */
839 if (flags
& MSG_TRUNC
)
842 if (!(flags
& MSG_PEEK
))
843 sk_eat_skb(sk
, skb
, 0);
851 EXPORT_SYMBOL_GPL(dccp_recvmsg
);
853 int inet_dccp_listen(struct socket
*sock
, int backlog
)
855 struct sock
*sk
= sock
->sk
;
856 unsigned char old_state
;
862 if (sock
->state
!= SS_UNCONNECTED
|| sock
->type
!= SOCK_DCCP
)
865 old_state
= sk
->sk_state
;
866 if (!((1 << old_state
) & (DCCPF_CLOSED
| DCCPF_LISTEN
)))
869 /* Really, if the socket is already in listen state
870 * we can only allow the backlog to be adjusted.
872 if (old_state
!= DCCP_LISTEN
) {
874 * FIXME: here it probably should be sk->sk_prot->listen_start
875 * see tcp_listen_start
877 err
= dccp_listen_start(sk
, backlog
);
881 sk
->sk_max_ack_backlog
= backlog
;
889 EXPORT_SYMBOL_GPL(inet_dccp_listen
);
891 static void dccp_terminate_connection(struct sock
*sk
)
893 u8 next_state
= DCCP_CLOSED
;
895 switch (sk
->sk_state
) {
896 case DCCP_PASSIVE_CLOSE
:
897 case DCCP_PASSIVE_CLOSEREQ
:
898 dccp_finish_passive_close(sk
);
901 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk
);
902 inet_csk_clear_xmit_timer(sk
, ICSK_TIME_DACK
);
905 dccp_send_close(sk
, 1);
907 if (dccp_sk(sk
)->dccps_role
== DCCP_ROLE_SERVER
&&
908 !dccp_sk(sk
)->dccps_server_timewait
)
909 next_state
= DCCP_ACTIVE_CLOSEREQ
;
911 next_state
= DCCP_CLOSING
;
914 dccp_set_state(sk
, next_state
);
918 void dccp_close(struct sock
*sk
, long timeout
)
920 struct dccp_sock
*dp
= dccp_sk(sk
);
922 u32 data_was_unread
= 0;
927 sk
->sk_shutdown
= SHUTDOWN_MASK
;
929 if (sk
->sk_state
== DCCP_LISTEN
) {
930 dccp_set_state(sk
, DCCP_CLOSED
);
933 inet_csk_listen_stop(sk
);
935 goto adjudge_to_death
;
938 sk_stop_timer(sk
, &dp
->dccps_xmit_timer
);
941 * We need to flush the recv. buffs. We do this only on the
942 * descriptor close, not protocol-sourced closes, because the
943 *reader process may not have drained the data yet!
945 while ((skb
= __skb_dequeue(&sk
->sk_receive_queue
)) != NULL
) {
946 data_was_unread
+= skb
->len
;
950 if (data_was_unread
) {
951 /* Unread data was tossed, send an appropriate Reset Code */
952 DCCP_WARN("DCCP: ABORT -- %u bytes unread\n", data_was_unread
);
953 dccp_send_reset(sk
, DCCP_RESET_CODE_ABORTED
);
954 dccp_set_state(sk
, DCCP_CLOSED
);
955 } else if (sock_flag(sk
, SOCK_LINGER
) && !sk
->sk_lingertime
) {
956 /* Check zero linger _after_ checking for unread data. */
957 sk
->sk_prot
->disconnect(sk
, 0);
958 } else if (sk
->sk_state
!= DCCP_CLOSED
) {
959 dccp_terminate_connection(sk
);
962 sk_stream_wait_close(sk
, timeout
);
965 state
= sk
->sk_state
;
970 * It is the last release_sock in its life. It will remove backlog.
974 * Now socket is owned by kernel and we acquire BH lock
975 * to finish close. No need to check for user refs.
979 WARN_ON(sock_owned_by_user(sk
));
981 percpu_counter_inc(sk
->sk_prot
->orphan_count
);
983 /* Have we already been destroyed by a softirq or backlog? */
984 if (state
!= DCCP_CLOSED
&& sk
->sk_state
== DCCP_CLOSED
)
987 if (sk
->sk_state
== DCCP_CLOSED
)
988 inet_csk_destroy_sock(sk
);
990 /* Otherwise, socket is reprieved until protocol close. */
998 EXPORT_SYMBOL_GPL(dccp_close
);
1000 void dccp_shutdown(struct sock
*sk
, int how
)
1002 dccp_pr_debug("called shutdown(%x)\n", how
);
1005 EXPORT_SYMBOL_GPL(dccp_shutdown
);
1007 static inline int dccp_mib_init(void)
1009 return snmp_mib_init((void __percpu
**)dccp_statistics
,
1010 sizeof(struct dccp_mib
));
1013 static inline void dccp_mib_exit(void)
1015 snmp_mib_free((void __percpu
**)dccp_statistics
);
1018 static int thash_entries
;
1019 module_param(thash_entries
, int, 0444);
1020 MODULE_PARM_DESC(thash_entries
, "Number of ehash buckets");
1022 #ifdef CONFIG_IP_DCCP_DEBUG
1024 module_param(dccp_debug
, bool, 0644);
1025 MODULE_PARM_DESC(dccp_debug
, "Enable debug messages");
1027 EXPORT_SYMBOL_GPL(dccp_debug
);
1030 static int __init
dccp_init(void)
1033 int ehash_order
, bhash_order
, i
;
1036 BUILD_BUG_ON(sizeof(struct dccp_skb_cb
) >
1037 FIELD_SIZEOF(struct sk_buff
, cb
));
1038 rc
= percpu_counter_init(&dccp_orphan_count
, 0);
1042 inet_hashinfo_init(&dccp_hashinfo
);
1043 dccp_hashinfo
.bind_bucket_cachep
=
1044 kmem_cache_create("dccp_bind_bucket",
1045 sizeof(struct inet_bind_bucket
), 0,
1046 SLAB_HWCACHE_ALIGN
, NULL
);
1047 if (!dccp_hashinfo
.bind_bucket_cachep
)
1048 goto out_free_percpu
;
1051 * Size and allocate the main established and bind bucket
1054 * The methodology is similar to that of the buffer cache.
1056 if (totalram_pages
>= (128 * 1024))
1057 goal
= totalram_pages
>> (21 - PAGE_SHIFT
);
1059 goal
= totalram_pages
>> (23 - PAGE_SHIFT
);
1062 goal
= (thash_entries
*
1063 sizeof(struct inet_ehash_bucket
)) >> PAGE_SHIFT
;
1064 for (ehash_order
= 0; (1UL << ehash_order
) < goal
; ehash_order
++)
1067 unsigned long hash_size
= (1UL << ehash_order
) * PAGE_SIZE
/
1068 sizeof(struct inet_ehash_bucket
);
1070 while (hash_size
& (hash_size
- 1))
1072 dccp_hashinfo
.ehash_mask
= hash_size
- 1;
1073 dccp_hashinfo
.ehash
= (struct inet_ehash_bucket
*)
1074 __get_free_pages(GFP_ATOMIC
|__GFP_NOWARN
, ehash_order
);
1075 } while (!dccp_hashinfo
.ehash
&& --ehash_order
> 0);
1077 if (!dccp_hashinfo
.ehash
) {
1078 DCCP_CRIT("Failed to allocate DCCP established hash table");
1079 goto out_free_bind_bucket_cachep
;
1082 for (i
= 0; i
<= dccp_hashinfo
.ehash_mask
; i
++) {
1083 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo
.ehash
[i
].chain
, i
);
1084 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo
.ehash
[i
].twchain
, i
);
1087 if (inet_ehash_locks_alloc(&dccp_hashinfo
))
1088 goto out_free_dccp_ehash
;
1090 bhash_order
= ehash_order
;
1093 dccp_hashinfo
.bhash_size
= (1UL << bhash_order
) * PAGE_SIZE
/
1094 sizeof(struct inet_bind_hashbucket
);
1095 if ((dccp_hashinfo
.bhash_size
> (64 * 1024)) &&
1098 dccp_hashinfo
.bhash
= (struct inet_bind_hashbucket
*)
1099 __get_free_pages(GFP_ATOMIC
|__GFP_NOWARN
, bhash_order
);
1100 } while (!dccp_hashinfo
.bhash
&& --bhash_order
>= 0);
1102 if (!dccp_hashinfo
.bhash
) {
1103 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1104 goto out_free_dccp_locks
;
1107 for (i
= 0; i
< dccp_hashinfo
.bhash_size
; i
++) {
1108 spin_lock_init(&dccp_hashinfo
.bhash
[i
].lock
);
1109 INIT_HLIST_HEAD(&dccp_hashinfo
.bhash
[i
].chain
);
1112 rc
= dccp_mib_init();
1114 goto out_free_dccp_bhash
;
1116 rc
= dccp_ackvec_init();
1118 goto out_free_dccp_mib
;
1120 rc
= dccp_sysctl_init();
1122 goto out_ackvec_exit
;
1124 rc
= ccid_initialize_builtins();
1126 goto out_sysctl_exit
;
1128 dccp_timestamping_init();
1138 out_free_dccp_bhash
:
1139 free_pages((unsigned long)dccp_hashinfo
.bhash
, bhash_order
);
1140 out_free_dccp_locks
:
1141 inet_ehash_locks_free(&dccp_hashinfo
);
1142 out_free_dccp_ehash
:
1143 free_pages((unsigned long)dccp_hashinfo
.ehash
, ehash_order
);
1144 out_free_bind_bucket_cachep
:
1145 kmem_cache_destroy(dccp_hashinfo
.bind_bucket_cachep
);
1147 percpu_counter_destroy(&dccp_orphan_count
);
1149 dccp_hashinfo
.bhash
= NULL
;
1150 dccp_hashinfo
.ehash
= NULL
;
1151 dccp_hashinfo
.bind_bucket_cachep
= NULL
;
1155 static void __exit
dccp_fini(void)
1157 ccid_cleanup_builtins();
1159 free_pages((unsigned long)dccp_hashinfo
.bhash
,
1160 get_order(dccp_hashinfo
.bhash_size
*
1161 sizeof(struct inet_bind_hashbucket
)));
1162 free_pages((unsigned long)dccp_hashinfo
.ehash
,
1163 get_order((dccp_hashinfo
.ehash_mask
+ 1) *
1164 sizeof(struct inet_ehash_bucket
)));
1165 inet_ehash_locks_free(&dccp_hashinfo
);
1166 kmem_cache_destroy(dccp_hashinfo
.bind_bucket_cachep
);
1169 percpu_counter_destroy(&dccp_orphan_count
);
1172 module_init(dccp_init
);
1173 module_exit(dccp_fini
);
1175 MODULE_LICENSE("GPL");
1176 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1177 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");