1 /* AF_RXRPC sendmsg() implementation.
3 * Copyright (C) 2007, 2016 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 Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/net.h>
15 #include <linux/gfp.h>
16 #include <linux/skbuff.h>
17 #include <linux/export.h>
18 #include <linux/sched/signal.h>
21 #include <net/af_rxrpc.h>
22 #include "ar-internal.h"
25 RXRPC_CMD_SEND_DATA
, /* send data message */
26 RXRPC_CMD_SEND_ABORT
, /* request abort generation */
27 RXRPC_CMD_ACCEPT
, /* [server] accept incoming call */
28 RXRPC_CMD_REJECT_BUSY
, /* [server] reject a call as busy */
32 * wait for space to appear in the transmit/ACK window
33 * - caller holds the socket locked
35 static int rxrpc_wait_for_tx_window(struct rxrpc_sock
*rx
,
36 struct rxrpc_call
*call
,
39 DECLARE_WAITQUEUE(myself
, current
);
43 call
->tx_hard_ack
, call
->tx_top
, call
->tx_winsize
);
45 add_wait_queue(&call
->waitq
, &myself
);
48 set_current_state(TASK_INTERRUPTIBLE
);
50 if (call
->tx_top
- call
->tx_hard_ack
<
51 min_t(unsigned int, call
->tx_winsize
,
52 call
->cong_cwnd
+ call
->cong_extra
))
54 if (call
->state
>= RXRPC_CALL_COMPLETE
) {
58 if (signal_pending(current
)) {
59 ret
= sock_intr_errno(*timeo
);
63 trace_rxrpc_transmit(call
, rxrpc_transmit_wait
);
64 release_sock(&rx
->sk
);
65 *timeo
= schedule_timeout(*timeo
);
69 remove_wait_queue(&call
->waitq
, &myself
);
70 set_current_state(TASK_RUNNING
);
76 * Schedule an instant Tx resend.
78 static inline void rxrpc_instant_resend(struct rxrpc_call
*call
, int ix
)
80 spin_lock_bh(&call
->lock
);
82 if (call
->state
< RXRPC_CALL_COMPLETE
) {
83 call
->rxtx_annotations
[ix
] = RXRPC_TX_ANNO_RETRANS
;
84 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND
, &call
->events
))
85 rxrpc_queue_call(call
);
88 spin_unlock_bh(&call
->lock
);
92 * Queue a DATA packet for transmission, set the resend timeout and send the
95 static void rxrpc_queue_packet(struct rxrpc_call
*call
, struct sk_buff
*skb
,
98 struct rxrpc_skb_priv
*sp
= rxrpc_skb(skb
);
99 rxrpc_seq_t seq
= sp
->hdr
.seq
;
101 u8 annotation
= RXRPC_TX_ANNO_UNACK
;
103 _net("queue skb %p [%d]", skb
, seq
);
105 ASSERTCMP(seq
, ==, call
->tx_top
+ 1);
108 annotation
|= RXRPC_TX_ANNO_LAST
;
110 /* We have to set the timestamp before queueing as the retransmit
111 * algorithm can see the packet as soon as we queue it.
113 skb
->tstamp
= ktime_get_real();
115 ix
= seq
& RXRPC_RXTX_BUFF_MASK
;
116 rxrpc_get_skb(skb
, rxrpc_skb_tx_got
);
117 call
->rxtx_annotations
[ix
] = annotation
;
119 call
->rxtx_buffer
[ix
] = skb
;
122 trace_rxrpc_transmit(call
, rxrpc_transmit_queue_last
);
124 trace_rxrpc_transmit(call
, rxrpc_transmit_queue
);
126 if (last
|| call
->state
== RXRPC_CALL_SERVER_ACK_REQUEST
) {
127 _debug("________awaiting reply/ACK__________");
128 write_lock_bh(&call
->state_lock
);
129 switch (call
->state
) {
130 case RXRPC_CALL_CLIENT_SEND_REQUEST
:
131 call
->state
= RXRPC_CALL_CLIENT_AWAIT_REPLY
;
133 case RXRPC_CALL_SERVER_ACK_REQUEST
:
134 call
->state
= RXRPC_CALL_SERVER_SEND_REPLY
;
135 call
->ack_at
= call
->expire_at
;
136 if (call
->ackr_reason
== RXRPC_ACK_DELAY
)
137 call
->ackr_reason
= 0;
138 __rxrpc_set_timer(call
, rxrpc_timer_init_for_send_reply
,
142 case RXRPC_CALL_SERVER_SEND_REPLY
:
143 call
->state
= RXRPC_CALL_SERVER_AWAIT_ACK
;
148 write_unlock_bh(&call
->state_lock
);
151 if (seq
== 1 && rxrpc_is_client_call(call
))
152 rxrpc_expose_client_call(call
);
154 ret
= rxrpc_send_data_packet(call
, skb
, false);
156 _debug("need instant resend %d", ret
);
157 rxrpc_instant_resend(call
, ix
);
159 ktime_t now
= ktime_get_real(), resend_at
;
161 resend_at
= ktime_add_ms(now
, rxrpc_resend_timeout
);
163 if (ktime_before(resend_at
, call
->resend_at
)) {
164 call
->resend_at
= resend_at
;
165 rxrpc_set_timer(call
, rxrpc_timer_set_for_send
, now
);
169 rxrpc_free_skb(skb
, rxrpc_skb_tx_freed
);
174 * send data through a socket
175 * - must be called in process context
176 * - caller holds the socket locked
178 static int rxrpc_send_data(struct rxrpc_sock
*rx
,
179 struct rxrpc_call
*call
,
180 struct msghdr
*msg
, size_t len
)
182 struct rxrpc_skb_priv
*sp
;
184 struct sock
*sk
= &rx
->sk
;
189 timeo
= sock_sndtimeo(sk
, msg
->msg_flags
& MSG_DONTWAIT
);
191 /* this should be in poll */
192 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE
, sk
);
194 if (sk
->sk_err
|| (sk
->sk_shutdown
& SEND_SHUTDOWN
))
197 more
= msg
->msg_flags
& MSG_MORE
;
199 skb
= call
->tx_pending
;
200 call
->tx_pending
= NULL
;
201 rxrpc_see_skb(skb
, rxrpc_skb_tx_seen
);
205 /* Check to see if there's a ping ACK to reply to. */
206 if (call
->ackr_reason
== RXRPC_ACK_PING_RESPONSE
)
207 rxrpc_send_ack_packet(call
, false);
210 size_t size
, chunk
, max
, space
;
214 if (call
->tx_top
- call
->tx_hard_ack
>=
215 min_t(unsigned int, call
->tx_winsize
,
216 call
->cong_cwnd
+ call
->cong_extra
)) {
218 if (msg
->msg_flags
& MSG_DONTWAIT
)
220 ret
= rxrpc_wait_for_tx_window(rx
, call
,
226 max
= RXRPC_JUMBO_DATALEN
;
227 max
-= call
->conn
->security_size
;
228 max
&= ~(call
->conn
->size_align
- 1UL);
231 if (chunk
> msg_data_left(msg
) && !more
)
232 chunk
= msg_data_left(msg
);
234 space
= chunk
+ call
->conn
->size_align
;
235 space
&= ~(call
->conn
->size_align
- 1UL);
237 size
= space
+ call
->conn
->security_size
;
239 _debug("SIZE: %zu/%zu/%zu", chunk
, space
, size
);
241 /* create a buffer that we can retain until it's ACK'd */
242 skb
= sock_alloc_send_skb(
243 sk
, size
, msg
->msg_flags
& MSG_DONTWAIT
, &ret
);
247 rxrpc_new_skb(skb
, rxrpc_skb_tx_new
);
249 _debug("ALLOC SEND %p", skb
);
251 ASSERTCMP(skb
->mark
, ==, 0);
253 _debug("HS: %u", call
->conn
->security_size
);
254 skb_reserve(skb
, call
->conn
->security_size
);
255 skb
->len
+= call
->conn
->security_size
;
259 if (sp
->remain
> skb_tailroom(skb
))
260 sp
->remain
= skb_tailroom(skb
);
262 _net("skb: hr %d, tr %d, hl %d, rm %d",
268 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
274 /* append next segment of data to the current buffer */
275 if (msg_data_left(msg
) > 0) {
276 int copy
= skb_tailroom(skb
);
277 ASSERTCMP(copy
, >, 0);
278 if (copy
> msg_data_left(msg
))
279 copy
= msg_data_left(msg
);
280 if (copy
> sp
->remain
)
284 ret
= skb_add_data(skb
, &msg
->msg_iter
, copy
);
293 /* check for the far side aborting the call or a network error
295 if (call
->state
== RXRPC_CALL_COMPLETE
)
296 goto call_terminated
;
298 /* add the packet to the send queue if it's now full */
299 if (sp
->remain
<= 0 ||
300 (msg_data_left(msg
) == 0 && !more
)) {
301 struct rxrpc_connection
*conn
= call
->conn
;
305 /* pad out if we're using security */
306 if (conn
->security_ix
) {
307 pad
= conn
->security_size
+ skb
->mark
;
308 pad
= conn
->size_align
- pad
;
309 pad
&= conn
->size_align
- 1;
310 _debug("pad %zu", pad
);
312 memset(skb_put(skb
, pad
), 0, pad
);
315 seq
= call
->tx_top
+ 1;
319 sp
->hdr
.flags
= conn
->out_clientflag
;
321 if (msg_data_left(msg
) == 0 && !more
)
322 sp
->hdr
.flags
|= RXRPC_LAST_PACKET
;
323 else if (call
->tx_top
- call
->tx_hard_ack
<
325 sp
->hdr
.flags
|= RXRPC_MORE_PACKETS
;
327 ret
= conn
->security
->secure_packet(
328 call
, skb
, skb
->mark
, skb
->head
);
332 rxrpc_queue_packet(call
, skb
, !msg_data_left(msg
) && !more
);
335 } while (msg_data_left(msg
) > 0);
340 call
->tx_pending
= skb
;
341 _leave(" = %d", ret
);
345 rxrpc_free_skb(skb
, rxrpc_skb_tx_freed
);
346 _leave(" = %d", -call
->error
);
360 * extract control messages from the sendmsg() control buffer
362 static int rxrpc_sendmsg_cmsg(struct msghdr
*msg
,
363 unsigned long *user_call_ID
,
364 enum rxrpc_command
*command
,
368 struct cmsghdr
*cmsg
;
369 bool got_user_ID
= false;
372 *command
= RXRPC_CMD_SEND_DATA
;
374 if (msg
->msg_controllen
== 0)
377 for_each_cmsghdr(cmsg
, msg
) {
378 if (!CMSG_OK(msg
, cmsg
))
381 len
= cmsg
->cmsg_len
- sizeof(struct cmsghdr
);
382 _debug("CMSG %d, %d, %d",
383 cmsg
->cmsg_level
, cmsg
->cmsg_type
, len
);
385 if (cmsg
->cmsg_level
!= SOL_RXRPC
)
388 switch (cmsg
->cmsg_type
) {
389 case RXRPC_USER_CALL_ID
:
390 if (msg
->msg_flags
& MSG_CMSG_COMPAT
) {
391 if (len
!= sizeof(u32
))
393 *user_call_ID
= *(u32
*) CMSG_DATA(cmsg
);
395 if (len
!= sizeof(unsigned long))
397 *user_call_ID
= *(unsigned long *)
400 _debug("User Call ID %lx", *user_call_ID
);
405 if (*command
!= RXRPC_CMD_SEND_DATA
)
407 *command
= RXRPC_CMD_SEND_ABORT
;
408 if (len
!= sizeof(*abort_code
))
410 *abort_code
= *(unsigned int *) CMSG_DATA(cmsg
);
411 _debug("Abort %x", *abort_code
);
412 if (*abort_code
== 0)
417 if (*command
!= RXRPC_CMD_SEND_DATA
)
419 *command
= RXRPC_CMD_ACCEPT
;
424 case RXRPC_EXCLUSIVE_CALL
:
441 * Create a new client call for sendmsg().
443 static struct rxrpc_call
*
444 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock
*rx
, struct msghdr
*msg
,
445 unsigned long user_call_ID
, bool exclusive
)
447 struct rxrpc_conn_parameters cp
;
448 struct rxrpc_call
*call
;
451 DECLARE_SOCKADDR(struct sockaddr_rxrpc
*, srx
, msg
->msg_name
);
456 return ERR_PTR(-EDESTADDRREQ
);
459 if (key
&& !rx
->key
->payload
.data
[0])
462 memset(&cp
, 0, sizeof(cp
));
463 cp
.local
= rx
->local
;
465 cp
.security_level
= rx
->min_sec_level
;
466 cp
.exclusive
= rx
->exclusive
| exclusive
;
467 cp
.service_id
= srx
->srx_service
;
468 call
= rxrpc_new_client_call(rx
, &cp
, srx
, user_call_ID
, GFP_KERNEL
);
470 _leave(" = %p\n", call
);
475 * send a message forming part of a client call through an RxRPC socket
476 * - caller holds the socket locked
477 * - the socket may be either a client socket or a server socket
479 int rxrpc_do_sendmsg(struct rxrpc_sock
*rx
, struct msghdr
*msg
, size_t len
)
481 enum rxrpc_command cmd
;
482 struct rxrpc_call
*call
;
483 unsigned long user_call_ID
= 0;
484 bool exclusive
= false;
490 ret
= rxrpc_sendmsg_cmsg(msg
, &user_call_ID
, &cmd
, &abort_code
,
495 if (cmd
== RXRPC_CMD_ACCEPT
) {
496 if (rx
->sk
.sk_state
!= RXRPC_SERVER_LISTENING
)
498 call
= rxrpc_accept_call(rx
, user_call_ID
, NULL
);
500 return PTR_ERR(call
);
501 rxrpc_put_call(call
, rxrpc_call_put
);
505 call
= rxrpc_find_call_by_user_ID(rx
, user_call_ID
);
507 if (cmd
!= RXRPC_CMD_SEND_DATA
)
509 call
= rxrpc_new_client_call_for_sendmsg(rx
, msg
, user_call_ID
,
512 return PTR_ERR(call
);
515 _debug("CALL %d USR %lx ST %d on CONN %p",
516 call
->debug_id
, call
->user_call_ID
, call
->state
, call
->conn
);
518 if (call
->state
>= RXRPC_CALL_COMPLETE
) {
519 /* it's too late for this call */
521 } else if (cmd
== RXRPC_CMD_SEND_ABORT
) {
523 if (rxrpc_abort_call("CMD", call
, 0, abort_code
, ECONNABORTED
))
524 ret
= rxrpc_send_abort_packet(call
);
525 } else if (cmd
!= RXRPC_CMD_SEND_DATA
) {
527 } else if (rxrpc_is_client_call(call
) &&
528 call
->state
!= RXRPC_CALL_CLIENT_SEND_REQUEST
) {
529 /* request phase complete for this client call */
531 } else if (rxrpc_is_service_call(call
) &&
532 call
->state
!= RXRPC_CALL_SERVER_ACK_REQUEST
&&
533 call
->state
!= RXRPC_CALL_SERVER_SEND_REPLY
) {
534 /* Reply phase not begun or not complete for service call. */
537 ret
= rxrpc_send_data(rx
, call
, msg
, len
);
540 rxrpc_put_call(call
, rxrpc_call_put
);
541 _leave(" = %d", ret
);
546 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
547 * @sock: The socket the call is on
548 * @call: The call to send data through
549 * @msg: The data to send
550 * @len: The amount of data to send
552 * Allow a kernel service to send data on a call. The call must be in an state
553 * appropriate to sending data. No control data should be supplied in @msg,
554 * nor should an address be supplied. MSG_MORE should be flagged if there's
555 * more data to come, otherwise this data will end the transmission phase.
557 int rxrpc_kernel_send_data(struct socket
*sock
, struct rxrpc_call
*call
,
558 struct msghdr
*msg
, size_t len
)
562 _enter("{%d,%s},", call
->debug_id
, rxrpc_call_states
[call
->state
]);
564 ASSERTCMP(msg
->msg_name
, ==, NULL
);
565 ASSERTCMP(msg
->msg_control
, ==, NULL
);
569 _debug("CALL %d USR %lx ST %d on CONN %p",
570 call
->debug_id
, call
->user_call_ID
, call
->state
, call
->conn
);
572 if (call
->state
>= RXRPC_CALL_COMPLETE
) {
573 ret
= -ESHUTDOWN
; /* it's too late for this call */
574 } else if (call
->state
!= RXRPC_CALL_CLIENT_SEND_REQUEST
&&
575 call
->state
!= RXRPC_CALL_SERVER_ACK_REQUEST
&&
576 call
->state
!= RXRPC_CALL_SERVER_SEND_REPLY
) {
577 ret
= -EPROTO
; /* request phase complete for this client call */
579 ret
= rxrpc_send_data(rxrpc_sk(sock
->sk
), call
, msg
, len
);
582 release_sock(sock
->sk
);
583 _leave(" = %d", ret
);
586 EXPORT_SYMBOL(rxrpc_kernel_send_data
);
589 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
590 * @sock: The socket the call is on
591 * @call: The call to be aborted
592 * @abort_code: The abort code to stick into the ABORT packet
593 * @error: Local error value
594 * @why: 3-char string indicating why.
596 * Allow a kernel service to abort a call, if it's still in an abortable state.
598 void rxrpc_kernel_abort_call(struct socket
*sock
, struct rxrpc_call
*call
,
599 u32 abort_code
, int error
, const char *why
)
601 _enter("{%d},%d,%d,%s", call
->debug_id
, abort_code
, error
, why
);
605 if (rxrpc_abort_call(why
, call
, 0, abort_code
, error
))
606 rxrpc_send_abort_packet(call
);
608 release_sock(sock
->sk
);
612 EXPORT_SYMBOL(rxrpc_kernel_abort_call
);