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 #ifdef CONFIG_IP_DCCP_DEBUG
54 static const char *dccp_state_name(const int state
)
56 static const char *const dccp_state_names
[] = {
58 [DCCP_REQUESTING
] = "REQUESTING",
59 [DCCP_PARTOPEN
] = "PARTOPEN",
60 [DCCP_LISTEN
] = "LISTEN",
61 [DCCP_RESPOND
] = "RESPOND",
62 [DCCP_CLOSING
] = "CLOSING",
63 [DCCP_ACTIVE_CLOSEREQ
] = "CLOSEREQ",
64 [DCCP_PASSIVE_CLOSE
] = "PASSIVE_CLOSE",
65 [DCCP_PASSIVE_CLOSEREQ
] = "PASSIVE_CLOSEREQ",
66 [DCCP_TIME_WAIT
] = "TIME_WAIT",
67 [DCCP_CLOSED
] = "CLOSED",
70 if (state
>= DCCP_MAX_STATES
)
71 return "INVALID STATE!";
73 return dccp_state_names
[state
];
77 void dccp_set_state(struct sock
*sk
, const int state
)
79 const int oldstate
= sk
->sk_state
;
81 dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk
), sk
,
82 dccp_state_name(oldstate
), dccp_state_name(state
));
83 WARN_ON(state
== oldstate
);
87 if (oldstate
!= DCCP_OPEN
)
88 DCCP_INC_STATS(DCCP_MIB_CURRESTAB
);
89 /* Client retransmits all Confirm options until entering OPEN */
90 if (oldstate
== DCCP_PARTOPEN
)
91 dccp_feat_list_purge(&dccp_sk(sk
)->dccps_featneg
);
95 if (oldstate
== DCCP_OPEN
|| oldstate
== DCCP_ACTIVE_CLOSEREQ
||
96 oldstate
== DCCP_CLOSING
)
97 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS
);
99 sk
->sk_prot
->unhash(sk
);
100 if (inet_csk(sk
)->icsk_bind_hash
!= NULL
&&
101 !(sk
->sk_userlocks
& SOCK_BINDPORT_LOCK
))
105 if (oldstate
== DCCP_OPEN
)
106 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB
);
109 /* Change state AFTER socket is unhashed to avoid closed
110 * socket sitting in hash tables.
112 sk
->sk_state
= state
;
115 EXPORT_SYMBOL_GPL(dccp_set_state
);
117 static void dccp_finish_passive_close(struct sock
*sk
)
119 switch (sk
->sk_state
) {
120 case DCCP_PASSIVE_CLOSE
:
121 /* Node (client or server) has received Close packet. */
122 dccp_send_reset(sk
, DCCP_RESET_CODE_CLOSED
);
123 dccp_set_state(sk
, DCCP_CLOSED
);
125 case DCCP_PASSIVE_CLOSEREQ
:
127 * Client received CloseReq. We set the `active' flag so that
128 * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
130 dccp_send_close(sk
, 1);
131 dccp_set_state(sk
, DCCP_CLOSING
);
135 void dccp_done(struct sock
*sk
)
137 dccp_set_state(sk
, DCCP_CLOSED
);
138 dccp_clear_xmit_timers(sk
);
140 sk
->sk_shutdown
= SHUTDOWN_MASK
;
142 if (!sock_flag(sk
, SOCK_DEAD
))
143 sk
->sk_state_change(sk
);
145 inet_csk_destroy_sock(sk
);
148 EXPORT_SYMBOL_GPL(dccp_done
);
150 const char *dccp_packet_name(const int type
)
152 static const char *const dccp_packet_names
[] = {
153 [DCCP_PKT_REQUEST
] = "REQUEST",
154 [DCCP_PKT_RESPONSE
] = "RESPONSE",
155 [DCCP_PKT_DATA
] = "DATA",
156 [DCCP_PKT_ACK
] = "ACK",
157 [DCCP_PKT_DATAACK
] = "DATAACK",
158 [DCCP_PKT_CLOSEREQ
] = "CLOSEREQ",
159 [DCCP_PKT_CLOSE
] = "CLOSE",
160 [DCCP_PKT_RESET
] = "RESET",
161 [DCCP_PKT_SYNC
] = "SYNC",
162 [DCCP_PKT_SYNCACK
] = "SYNCACK",
165 if (type
>= DCCP_NR_PKT_TYPES
)
168 return dccp_packet_names
[type
];
171 EXPORT_SYMBOL_GPL(dccp_packet_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_tx_qlen
= sysctl_dccp_tx_qlen
;
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_is_writeable(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_is_writeable(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
= memdup_user(optval
, optlen
);
481 if (type
== DCCP_SOCKOPT_TX_CCID
|| type
== DCCP_SOCKOPT_CCID
)
482 rc
= dccp_feat_register_sp(sk
, DCCPF_CCID
, 1, val
, optlen
);
484 if (!rc
&& (type
== DCCP_SOCKOPT_RX_CCID
|| type
== DCCP_SOCKOPT_CCID
))
485 rc
= dccp_feat_register_sp(sk
, DCCPF_CCID
, 0, val
, optlen
);
492 static int do_dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
493 char __user
*optval
, unsigned int optlen
)
495 struct dccp_sock
*dp
= dccp_sk(sk
);
499 case DCCP_SOCKOPT_PACKET_SIZE
:
500 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
502 case DCCP_SOCKOPT_CHANGE_L
:
503 case DCCP_SOCKOPT_CHANGE_R
:
504 DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
506 case DCCP_SOCKOPT_CCID
:
507 case DCCP_SOCKOPT_RX_CCID
:
508 case DCCP_SOCKOPT_TX_CCID
:
509 return dccp_setsockopt_ccid(sk
, optname
, optval
, optlen
);
512 if (optlen
< (int)sizeof(int))
515 if (get_user(val
, (int __user
*)optval
))
518 if (optname
== DCCP_SOCKOPT_SERVICE
)
519 return dccp_setsockopt_service(sk
, val
, optval
, optlen
);
523 case DCCP_SOCKOPT_SERVER_TIMEWAIT
:
524 if (dp
->dccps_role
!= DCCP_ROLE_SERVER
)
527 dp
->dccps_server_timewait
= (val
!= 0);
529 case DCCP_SOCKOPT_SEND_CSCOV
:
530 err
= dccp_setsockopt_cscov(sk
, val
, false);
532 case DCCP_SOCKOPT_RECV_CSCOV
:
533 err
= dccp_setsockopt_cscov(sk
, val
, true);
535 case DCCP_SOCKOPT_QPOLICY_ID
:
536 if (sk
->sk_state
!= DCCP_CLOSED
)
538 else if (val
< 0 || val
>= DCCPQ_POLICY_MAX
)
541 dp
->dccps_qpolicy
= val
;
543 case DCCP_SOCKOPT_QPOLICY_TXQLEN
:
547 dp
->dccps_tx_qlen
= val
;
558 int dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
559 char __user
*optval
, unsigned int optlen
)
561 if (level
!= SOL_DCCP
)
562 return inet_csk(sk
)->icsk_af_ops
->setsockopt(sk
, level
,
565 return do_dccp_setsockopt(sk
, level
, optname
, optval
, optlen
);
568 EXPORT_SYMBOL_GPL(dccp_setsockopt
);
571 int compat_dccp_setsockopt(struct sock
*sk
, int level
, int optname
,
572 char __user
*optval
, unsigned int optlen
)
574 if (level
!= SOL_DCCP
)
575 return inet_csk_compat_setsockopt(sk
, level
, optname
,
577 return do_dccp_setsockopt(sk
, level
, optname
, optval
, optlen
);
580 EXPORT_SYMBOL_GPL(compat_dccp_setsockopt
);
583 static int dccp_getsockopt_service(struct sock
*sk
, int len
,
584 __be32 __user
*optval
,
587 const struct dccp_sock
*dp
= dccp_sk(sk
);
588 const struct dccp_service_list
*sl
;
589 int err
= -ENOENT
, slen
= 0, total_len
= sizeof(u32
);
592 if ((sl
= dp
->dccps_service_list
) != NULL
) {
593 slen
= sl
->dccpsl_nr
* sizeof(u32
);
602 if (put_user(total_len
, optlen
) ||
603 put_user(dp
->dccps_service
, optval
) ||
604 (sl
!= NULL
&& copy_to_user(optval
+ 1, sl
->dccpsl_list
, slen
)))
611 static int do_dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
612 char __user
*optval
, int __user
*optlen
)
614 struct dccp_sock
*dp
;
617 if (get_user(len
, optlen
))
620 if (len
< (int)sizeof(int))
626 case DCCP_SOCKOPT_PACKET_SIZE
:
627 DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
629 case DCCP_SOCKOPT_SERVICE
:
630 return dccp_getsockopt_service(sk
, len
,
631 (__be32 __user
*)optval
, optlen
);
632 case DCCP_SOCKOPT_GET_CUR_MPS
:
633 val
= dp
->dccps_mss_cache
;
635 case DCCP_SOCKOPT_AVAILABLE_CCIDS
:
636 return ccid_getsockopt_builtin_ccids(sk
, len
, optval
, optlen
);
637 case DCCP_SOCKOPT_TX_CCID
:
638 val
= ccid_get_current_tx_ccid(dp
);
642 case DCCP_SOCKOPT_RX_CCID
:
643 val
= ccid_get_current_rx_ccid(dp
);
647 case DCCP_SOCKOPT_SERVER_TIMEWAIT
:
648 val
= dp
->dccps_server_timewait
;
650 case DCCP_SOCKOPT_SEND_CSCOV
:
651 val
= dp
->dccps_pcslen
;
653 case DCCP_SOCKOPT_RECV_CSCOV
:
654 val
= dp
->dccps_pcrlen
;
656 case DCCP_SOCKOPT_QPOLICY_ID
:
657 val
= dp
->dccps_qpolicy
;
659 case DCCP_SOCKOPT_QPOLICY_TXQLEN
:
660 val
= dp
->dccps_tx_qlen
;
663 return ccid_hc_rx_getsockopt(dp
->dccps_hc_rx_ccid
, sk
, optname
,
664 len
, (u32 __user
*)optval
, optlen
);
666 return ccid_hc_tx_getsockopt(dp
->dccps_hc_tx_ccid
, sk
, optname
,
667 len
, (u32 __user
*)optval
, optlen
);
673 if (put_user(len
, optlen
) || copy_to_user(optval
, &val
, len
))
679 int dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
680 char __user
*optval
, int __user
*optlen
)
682 if (level
!= SOL_DCCP
)
683 return inet_csk(sk
)->icsk_af_ops
->getsockopt(sk
, level
,
686 return do_dccp_getsockopt(sk
, level
, optname
, optval
, optlen
);
689 EXPORT_SYMBOL_GPL(dccp_getsockopt
);
692 int compat_dccp_getsockopt(struct sock
*sk
, int level
, int optname
,
693 char __user
*optval
, int __user
*optlen
)
695 if (level
!= SOL_DCCP
)
696 return inet_csk_compat_getsockopt(sk
, level
, optname
,
698 return do_dccp_getsockopt(sk
, level
, optname
, optval
, optlen
);
701 EXPORT_SYMBOL_GPL(compat_dccp_getsockopt
);
704 static int dccp_msghdr_parse(struct msghdr
*msg
, struct sk_buff
*skb
)
706 struct cmsghdr
*cmsg
;
709 * Assign an (opaque) qpolicy priority value to skb->priority.
711 * We are overloading this skb field for use with the qpolicy subystem.
712 * The skb->priority is normally used for the SO_PRIORITY option, which
713 * is initialised from sk_priority. Since the assignment of sk_priority
714 * to skb->priority happens later (on layer 3), we overload this field
715 * for use with queueing priorities as long as the skb is on layer 4.
716 * The default priority value (if nothing is set) is 0.
720 for_each_cmsghdr(cmsg
, msg
) {
721 if (!CMSG_OK(msg
, cmsg
))
724 if (cmsg
->cmsg_level
!= SOL_DCCP
)
727 if (cmsg
->cmsg_type
<= DCCP_SCM_QPOLICY_MAX
&&
728 !dccp_qpolicy_param_ok(skb
->sk
, cmsg
->cmsg_type
))
731 switch (cmsg
->cmsg_type
) {
732 case DCCP_SCM_PRIORITY
:
733 if (cmsg
->cmsg_len
!= CMSG_LEN(sizeof(__u32
)))
735 skb
->priority
= *(__u32
*)CMSG_DATA(cmsg
);
744 int dccp_sendmsg(struct sock
*sk
, struct msghdr
*msg
, size_t len
)
746 const struct dccp_sock
*dp
= dccp_sk(sk
);
747 const int flags
= msg
->msg_flags
;
748 const int noblock
= flags
& MSG_DONTWAIT
;
753 if (len
> dp
->dccps_mss_cache
)
758 if (dccp_qpolicy_full(sk
)) {
763 timeo
= sock_sndtimeo(sk
, noblock
);
766 * We have to use sk_stream_wait_connect here to set sk_write_pending,
767 * so that the trick in dccp_rcv_request_sent_state_process.
769 /* Wait for a connection to finish. */
770 if ((1 << sk
->sk_state
) & ~(DCCPF_OPEN
| DCCPF_PARTOPEN
))
771 if ((rc
= sk_stream_wait_connect(sk
, &timeo
)) != 0)
774 size
= sk
->sk_prot
->max_header
+ len
;
776 skb
= sock_alloc_send_skb(sk
, size
, noblock
, &rc
);
781 skb_reserve(skb
, sk
->sk_prot
->max_header
);
782 rc
= memcpy_from_msg(skb_put(skb
, len
), msg
, len
);
786 rc
= dccp_msghdr_parse(msg
, skb
);
790 dccp_qpolicy_push(sk
, skb
);
792 * The xmit_timer is set if the TX CCID is rate-based and will expire
793 * when congestion control permits to release further packets into the
794 * network. Window-based CCIDs do not use this timer.
796 if (!timer_pending(&dp
->dccps_xmit_timer
))
806 EXPORT_SYMBOL_GPL(dccp_sendmsg
);
808 int dccp_recvmsg(struct sock
*sk
, struct msghdr
*msg
, size_t len
, int nonblock
,
809 int flags
, int *addr_len
)
811 const struct dccp_hdr
*dh
;
816 if (sk
->sk_state
== DCCP_LISTEN
) {
821 timeo
= sock_rcvtimeo(sk
, nonblock
);
824 struct sk_buff
*skb
= skb_peek(&sk
->sk_receive_queue
);
827 goto verify_sock_status
;
831 switch (dh
->dccph_type
) {
833 case DCCP_PKT_DATAACK
:
837 case DCCP_PKT_CLOSEREQ
:
838 if (!(flags
& MSG_PEEK
))
839 dccp_finish_passive_close(sk
);
842 dccp_pr_debug("found fin (%s) ok!\n",
843 dccp_packet_name(dh
->dccph_type
));
847 dccp_pr_debug("packet_type=%s\n",
848 dccp_packet_name(dh
->dccph_type
));
852 if (sock_flag(sk
, SOCK_DONE
)) {
858 len
= sock_error(sk
);
862 if (sk
->sk_shutdown
& RCV_SHUTDOWN
) {
867 if (sk
->sk_state
== DCCP_CLOSED
) {
868 if (!sock_flag(sk
, SOCK_DONE
)) {
869 /* This occurs when user tries to read
870 * from never connected socket.
884 if (signal_pending(current
)) {
885 len
= sock_intr_errno(timeo
);
889 sk_wait_data(sk
, &timeo
);
894 else if (len
< skb
->len
)
895 msg
->msg_flags
|= MSG_TRUNC
;
897 if (skb_copy_datagram_msg(skb
, 0, msg
, len
)) {
898 /* Exception. Bailout! */
902 if (flags
& MSG_TRUNC
)
905 if (!(flags
& MSG_PEEK
))
914 EXPORT_SYMBOL_GPL(dccp_recvmsg
);
916 int inet_dccp_listen(struct socket
*sock
, int backlog
)
918 struct sock
*sk
= sock
->sk
;
919 unsigned char old_state
;
925 if (sock
->state
!= SS_UNCONNECTED
|| sock
->type
!= SOCK_DCCP
)
928 old_state
= sk
->sk_state
;
929 if (!((1 << old_state
) & (DCCPF_CLOSED
| DCCPF_LISTEN
)))
932 /* Really, if the socket is already in listen state
933 * we can only allow the backlog to be adjusted.
935 if (old_state
!= DCCP_LISTEN
) {
937 * FIXME: here it probably should be sk->sk_prot->listen_start
938 * see tcp_listen_start
940 err
= dccp_listen_start(sk
, backlog
);
944 sk
->sk_max_ack_backlog
= backlog
;
952 EXPORT_SYMBOL_GPL(inet_dccp_listen
);
954 static void dccp_terminate_connection(struct sock
*sk
)
956 u8 next_state
= DCCP_CLOSED
;
958 switch (sk
->sk_state
) {
959 case DCCP_PASSIVE_CLOSE
:
960 case DCCP_PASSIVE_CLOSEREQ
:
961 dccp_finish_passive_close(sk
);
964 dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk
);
965 inet_csk_clear_xmit_timer(sk
, ICSK_TIME_DACK
);
968 dccp_send_close(sk
, 1);
970 if (dccp_sk(sk
)->dccps_role
== DCCP_ROLE_SERVER
&&
971 !dccp_sk(sk
)->dccps_server_timewait
)
972 next_state
= DCCP_ACTIVE_CLOSEREQ
;
974 next_state
= DCCP_CLOSING
;
977 dccp_set_state(sk
, next_state
);
981 void dccp_close(struct sock
*sk
, long timeout
)
983 struct dccp_sock
*dp
= dccp_sk(sk
);
985 u32 data_was_unread
= 0;
990 sk
->sk_shutdown
= SHUTDOWN_MASK
;
992 if (sk
->sk_state
== DCCP_LISTEN
) {
993 dccp_set_state(sk
, DCCP_CLOSED
);
996 inet_csk_listen_stop(sk
);
998 goto adjudge_to_death
;
1001 sk_stop_timer(sk
, &dp
->dccps_xmit_timer
);
1004 * We need to flush the recv. buffs. We do this only on the
1005 * descriptor close, not protocol-sourced closes, because the
1006 *reader process may not have drained the data yet!
1008 while ((skb
= __skb_dequeue(&sk
->sk_receive_queue
)) != NULL
) {
1009 data_was_unread
+= skb
->len
;
1013 if (data_was_unread
) {
1014 /* Unread data was tossed, send an appropriate Reset Code */
1015 DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread
);
1016 dccp_send_reset(sk
, DCCP_RESET_CODE_ABORTED
);
1017 dccp_set_state(sk
, DCCP_CLOSED
);
1018 } else if (sock_flag(sk
, SOCK_LINGER
) && !sk
->sk_lingertime
) {
1019 /* Check zero linger _after_ checking for unread data. */
1020 sk
->sk_prot
->disconnect(sk
, 0);
1021 } else if (sk
->sk_state
!= DCCP_CLOSED
) {
1023 * Normal connection termination. May need to wait if there are
1024 * still packets in the TX queue that are delayed by the CCID.
1026 dccp_flush_write_queue(sk
, &timeout
);
1027 dccp_terminate_connection(sk
);
1031 * Flush write queue. This may be necessary in several cases:
1032 * - we have been closed by the peer but still have application data;
1033 * - abortive termination (unread data or zero linger time),
1034 * - normal termination but queue could not be flushed within time limit
1036 __skb_queue_purge(&sk
->sk_write_queue
);
1038 sk_stream_wait_close(sk
, timeout
);
1041 state
= sk
->sk_state
;
1046 * It is the last release_sock in its life. It will remove backlog.
1050 * Now socket is owned by kernel and we acquire BH lock
1051 * to finish close. No need to check for user refs.
1055 WARN_ON(sock_owned_by_user(sk
));
1057 percpu_counter_inc(sk
->sk_prot
->orphan_count
);
1059 /* Have we already been destroyed by a softirq or backlog? */
1060 if (state
!= DCCP_CLOSED
&& sk
->sk_state
== DCCP_CLOSED
)
1063 if (sk
->sk_state
== DCCP_CLOSED
)
1064 inet_csk_destroy_sock(sk
);
1066 /* Otherwise, socket is reprieved until protocol close. */
1074 EXPORT_SYMBOL_GPL(dccp_close
);
1076 void dccp_shutdown(struct sock
*sk
, int how
)
1078 dccp_pr_debug("called shutdown(%x)\n", how
);
1081 EXPORT_SYMBOL_GPL(dccp_shutdown
);
1083 static inline int __init
dccp_mib_init(void)
1085 dccp_statistics
= alloc_percpu(struct dccp_mib
);
1086 if (!dccp_statistics
)
1091 static inline void dccp_mib_exit(void)
1093 free_percpu(dccp_statistics
);
1096 static int thash_entries
;
1097 module_param(thash_entries
, int, 0444);
1098 MODULE_PARM_DESC(thash_entries
, "Number of ehash buckets");
1100 #ifdef CONFIG_IP_DCCP_DEBUG
1102 module_param(dccp_debug
, bool, 0644);
1103 MODULE_PARM_DESC(dccp_debug
, "Enable debug messages");
1105 EXPORT_SYMBOL_GPL(dccp_debug
);
1108 static int __init
dccp_init(void)
1111 int ehash_order
, bhash_order
, i
;
1114 BUILD_BUG_ON(sizeof(struct dccp_skb_cb
) >
1115 FIELD_SIZEOF(struct sk_buff
, cb
));
1116 rc
= percpu_counter_init(&dccp_orphan_count
, 0, GFP_KERNEL
);
1120 inet_hashinfo_init(&dccp_hashinfo
);
1121 dccp_hashinfo
.bind_bucket_cachep
=
1122 kmem_cache_create("dccp_bind_bucket",
1123 sizeof(struct inet_bind_bucket
), 0,
1124 SLAB_HWCACHE_ALIGN
, NULL
);
1125 if (!dccp_hashinfo
.bind_bucket_cachep
)
1126 goto out_free_percpu
;
1129 * Size and allocate the main established and bind bucket
1132 * The methodology is similar to that of the buffer cache.
1134 if (totalram_pages
>= (128 * 1024))
1135 goal
= totalram_pages
>> (21 - PAGE_SHIFT
);
1137 goal
= totalram_pages
>> (23 - PAGE_SHIFT
);
1140 goal
= (thash_entries
*
1141 sizeof(struct inet_ehash_bucket
)) >> PAGE_SHIFT
;
1142 for (ehash_order
= 0; (1UL << ehash_order
) < goal
; ehash_order
++)
1145 unsigned long hash_size
= (1UL << ehash_order
) * PAGE_SIZE
/
1146 sizeof(struct inet_ehash_bucket
);
1148 while (hash_size
& (hash_size
- 1))
1150 dccp_hashinfo
.ehash_mask
= hash_size
- 1;
1151 dccp_hashinfo
.ehash
= (struct inet_ehash_bucket
*)
1152 __get_free_pages(GFP_ATOMIC
|__GFP_NOWARN
, ehash_order
);
1153 } while (!dccp_hashinfo
.ehash
&& --ehash_order
> 0);
1155 if (!dccp_hashinfo
.ehash
) {
1156 DCCP_CRIT("Failed to allocate DCCP established hash table");
1157 goto out_free_bind_bucket_cachep
;
1160 for (i
= 0; i
<= dccp_hashinfo
.ehash_mask
; i
++)
1161 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo
.ehash
[i
].chain
, i
);
1163 if (inet_ehash_locks_alloc(&dccp_hashinfo
))
1164 goto out_free_dccp_ehash
;
1166 bhash_order
= ehash_order
;
1169 dccp_hashinfo
.bhash_size
= (1UL << bhash_order
) * PAGE_SIZE
/
1170 sizeof(struct inet_bind_hashbucket
);
1171 if ((dccp_hashinfo
.bhash_size
> (64 * 1024)) &&
1174 dccp_hashinfo
.bhash
= (struct inet_bind_hashbucket
*)
1175 __get_free_pages(GFP_ATOMIC
|__GFP_NOWARN
, bhash_order
);
1176 } while (!dccp_hashinfo
.bhash
&& --bhash_order
>= 0);
1178 if (!dccp_hashinfo
.bhash
) {
1179 DCCP_CRIT("Failed to allocate DCCP bind hash table");
1180 goto out_free_dccp_locks
;
1183 for (i
= 0; i
< dccp_hashinfo
.bhash_size
; i
++) {
1184 spin_lock_init(&dccp_hashinfo
.bhash
[i
].lock
);
1185 INIT_HLIST_HEAD(&dccp_hashinfo
.bhash
[i
].chain
);
1188 rc
= dccp_mib_init();
1190 goto out_free_dccp_bhash
;
1192 rc
= dccp_ackvec_init();
1194 goto out_free_dccp_mib
;
1196 rc
= dccp_sysctl_init();
1198 goto out_ackvec_exit
;
1200 rc
= ccid_initialize_builtins();
1202 goto out_sysctl_exit
;
1204 dccp_timestamping_init();
1214 out_free_dccp_bhash
:
1215 free_pages((unsigned long)dccp_hashinfo
.bhash
, bhash_order
);
1216 out_free_dccp_locks
:
1217 inet_ehash_locks_free(&dccp_hashinfo
);
1218 out_free_dccp_ehash
:
1219 free_pages((unsigned long)dccp_hashinfo
.ehash
, ehash_order
);
1220 out_free_bind_bucket_cachep
:
1221 kmem_cache_destroy(dccp_hashinfo
.bind_bucket_cachep
);
1223 percpu_counter_destroy(&dccp_orphan_count
);
1225 dccp_hashinfo
.bhash
= NULL
;
1226 dccp_hashinfo
.ehash
= NULL
;
1227 dccp_hashinfo
.bind_bucket_cachep
= NULL
;
1231 static void __exit
dccp_fini(void)
1233 ccid_cleanup_builtins();
1235 free_pages((unsigned long)dccp_hashinfo
.bhash
,
1236 get_order(dccp_hashinfo
.bhash_size
*
1237 sizeof(struct inet_bind_hashbucket
)));
1238 free_pages((unsigned long)dccp_hashinfo
.ehash
,
1239 get_order((dccp_hashinfo
.ehash_mask
+ 1) *
1240 sizeof(struct inet_ehash_bucket
)));
1241 inet_ehash_locks_free(&dccp_hashinfo
);
1242 kmem_cache_destroy(dccp_hashinfo
.bind_bucket_cachep
);
1245 percpu_counter_destroy(&dccp_orphan_count
);
1248 module_init(dccp_init
);
1249 module_exit(dccp_fini
);
1251 MODULE_LICENSE("GPL");
1252 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
1253 MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");