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);