blob: 89315009bab11f2f6c32db1bd50d0505d8210c46 [file] [log] [blame]
David Howells17926a72007-04-26 15:48:28 -07001/* RxRPC packet reception
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
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.
10 */
11
12#include <linux/module.h>
13#include <linux/net.h>
14#include <linux/skbuff.h>
15#include <linux/errqueue.h>
16#include <linux/udp.h>
17#include <linux/in.h>
18#include <linux/in6.h>
19#include <linux/icmp.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090020#include <linux/gfp.h>
David Howells17926a72007-04-26 15:48:28 -070021#include <net/sock.h>
22#include <net/af_rxrpc.h>
23#include <net/ip.h>
Herbert Xu1781f7f2007-12-11 11:30:32 -080024#include <net/udp.h>
Pavel Emelyanov02833282008-07-05 21:18:48 -070025#include <net/net_namespace.h>
David Howells17926a72007-04-26 15:48:28 -070026#include "ar-internal.h"
27
28unsigned long rxrpc_ack_timeout = 1;
29
30const char *rxrpc_pkts[] = {
31 "?00",
32 "DATA", "ACK", "BUSY", "ABORT", "ACKALL", "CHALL", "RESP", "DEBUG",
33 "?09", "?10", "?11", "?12", "?13", "?14", "?15"
34};
35
36/*
37 * queue a packet for recvmsg to pass to userspace
38 * - the caller must hold a lock on call->lock
39 * - must not be called with interrupts disabled (sk_filter() disables BH's)
40 * - eats the packet whether successful or not
41 * - there must be just one reference to the packet, which the caller passes to
42 * this function
43 */
44int rxrpc_queue_rcv_skb(struct rxrpc_call *call, struct sk_buff *skb,
45 bool force, bool terminal)
46{
47 struct rxrpc_skb_priv *sp;
David Howells651350d2007-04-26 15:50:17 -070048 struct rxrpc_sock *rx = call->socket;
David Howells17926a72007-04-26 15:48:28 -070049 struct sock *sk;
50 int skb_len, ret;
51
52 _enter(",,%d,%d", force, terminal);
53
54 ASSERT(!irqs_disabled());
55
56 sp = rxrpc_skb(skb);
57 ASSERTCMP(sp->call, ==, call);
58
59 /* if we've already posted the terminal message for a call, then we
60 * don't post any more */
61 if (test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) {
62 _debug("already terminated");
63 ASSERTCMP(call->state, >=, RXRPC_CALL_COMPLETE);
64 skb->destructor = NULL;
65 sp->call = NULL;
66 rxrpc_put_call(call);
67 rxrpc_free_skb(skb);
68 return 0;
69 }
70
David Howells651350d2007-04-26 15:50:17 -070071 sk = &rx->sk;
David Howells17926a72007-04-26 15:48:28 -070072
73 if (!force) {
74 /* cast skb->rcvbuf to unsigned... It's pointless, but
75 * reduces number of warnings when compiling with -W
76 * --ANK */
77// ret = -ENOBUFS;
78// if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
79// (unsigned) sk->sk_rcvbuf)
80// goto out;
81
82 ret = sk_filter(sk, skb);
83 if (ret < 0)
84 goto out;
85 }
86
87 spin_lock_bh(&sk->sk_receive_queue.lock);
88 if (!test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags) &&
89 !test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
90 call->socket->sk.sk_state != RXRPC_CLOSE) {
91 skb->destructor = rxrpc_packet_destructor;
92 skb->dev = NULL;
93 skb->sk = sk;
94 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
95
David Howells17926a72007-04-26 15:48:28 -070096 if (terminal) {
97 _debug("<<<< TERMINAL MESSAGE >>>>");
98 set_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags);
99 }
100
David Howells651350d2007-04-26 15:50:17 -0700101 /* allow interception by a kernel service */
102 if (rx->interceptor) {
103 rx->interceptor(sk, call->user_call_ID, skb);
104 spin_unlock_bh(&sk->sk_receive_queue.lock);
105 } else {
106
107 /* Cache the SKB length before we tack it onto the
108 * receive queue. Once it is added it no longer
109 * belongs to us and may be freed by other threads of
110 * control pulling packets from the queue */
111 skb_len = skb->len;
112
113 _net("post skb %p", skb);
114 __skb_queue_tail(&sk->sk_receive_queue, skb);
115 spin_unlock_bh(&sk->sk_receive_queue.lock);
116
117 if (!sock_flag(sk, SOCK_DEAD))
118 sk->sk_data_ready(sk, skb_len);
119 }
David Howells17926a72007-04-26 15:48:28 -0700120 skb = NULL;
121 } else {
122 spin_unlock_bh(&sk->sk_receive_queue.lock);
123 }
124 ret = 0;
125
126out:
127 /* release the socket buffer */
128 if (skb) {
129 skb->destructor = NULL;
130 sp->call = NULL;
131 rxrpc_put_call(call);
132 rxrpc_free_skb(skb);
133 }
134
135 _leave(" = %d", ret);
136 return ret;
137}
138
139/*
140 * process a DATA packet, posting the packet to the appropriate queue
141 * - eats the packet if successful
142 */
143static int rxrpc_fast_process_data(struct rxrpc_call *call,
144 struct sk_buff *skb, u32 seq)
145{
146 struct rxrpc_skb_priv *sp;
147 bool terminal;
148 int ret, ackbit, ack;
149
150 _enter("{%u,%u},,{%u}", call->rx_data_post, call->rx_first_oos, seq);
151
152 sp = rxrpc_skb(skb);
153 ASSERTCMP(sp->call, ==, NULL);
154
155 spin_lock(&call->lock);
156
157 if (call->state > RXRPC_CALL_COMPLETE)
158 goto discard;
159
160 ASSERTCMP(call->rx_data_expect, >=, call->rx_data_post);
161 ASSERTCMP(call->rx_data_post, >=, call->rx_data_recv);
162 ASSERTCMP(call->rx_data_recv, >=, call->rx_data_eaten);
163
164 if (seq < call->rx_data_post) {
165 _debug("dup #%u [-%u]", seq, call->rx_data_post);
166 ack = RXRPC_ACK_DUPLICATE;
167 ret = -ENOBUFS;
168 goto discard_and_ack;
169 }
170
171 /* we may already have the packet in the out of sequence queue */
172 ackbit = seq - (call->rx_data_eaten + 1);
173 ASSERTCMP(ackbit, >=, 0);
David S. Miller68c708f2007-04-26 20:20:21 -0700174 if (__test_and_set_bit(ackbit, call->ackr_window)) {
David Howells17926a72007-04-26 15:48:28 -0700175 _debug("dup oos #%u [%u,%u]",
176 seq, call->rx_data_eaten, call->rx_data_post);
177 ack = RXRPC_ACK_DUPLICATE;
178 goto discard_and_ack;
179 }
180
181 if (seq >= call->ackr_win_top) {
182 _debug("exceed #%u [%u]", seq, call->ackr_win_top);
David S. Miller68c708f2007-04-26 20:20:21 -0700183 __clear_bit(ackbit, call->ackr_window);
David Howells17926a72007-04-26 15:48:28 -0700184 ack = RXRPC_ACK_EXCEEDS_WINDOW;
185 goto discard_and_ack;
186 }
187
188 if (seq == call->rx_data_expect) {
189 clear_bit(RXRPC_CALL_EXPECT_OOS, &call->flags);
190 call->rx_data_expect++;
191 } else if (seq > call->rx_data_expect) {
192 _debug("oos #%u [%u]", seq, call->rx_data_expect);
193 call->rx_data_expect = seq + 1;
194 if (test_and_set_bit(RXRPC_CALL_EXPECT_OOS, &call->flags)) {
195 ack = RXRPC_ACK_OUT_OF_SEQUENCE;
196 goto enqueue_and_ack;
197 }
198 goto enqueue_packet;
199 }
200
201 if (seq != call->rx_data_post) {
202 _debug("ahead #%u [%u]", seq, call->rx_data_post);
203 goto enqueue_packet;
204 }
205
206 if (test_bit(RXRPC_CALL_RCVD_LAST, &call->flags))
207 goto protocol_error;
208
209 /* if the packet need security things doing to it, then it goes down
210 * the slow path */
211 if (call->conn->security)
212 goto enqueue_packet;
213
214 sp->call = call;
215 rxrpc_get_call(call);
216 terminal = ((sp->hdr.flags & RXRPC_LAST_PACKET) &&
217 !(sp->hdr.flags & RXRPC_CLIENT_INITIATED));
218 ret = rxrpc_queue_rcv_skb(call, skb, false, terminal);
219 if (ret < 0) {
220 if (ret == -ENOMEM || ret == -ENOBUFS) {
David S. Miller68c708f2007-04-26 20:20:21 -0700221 __clear_bit(ackbit, call->ackr_window);
David Howells17926a72007-04-26 15:48:28 -0700222 ack = RXRPC_ACK_NOSPACE;
223 goto discard_and_ack;
224 }
225 goto out;
226 }
227
228 skb = NULL;
229
230 _debug("post #%u", seq);
231 ASSERTCMP(call->rx_data_post, ==, seq);
232 call->rx_data_post++;
233
234 if (sp->hdr.flags & RXRPC_LAST_PACKET)
235 set_bit(RXRPC_CALL_RCVD_LAST, &call->flags);
236
237 /* if we've reached an out of sequence packet then we need to drain
238 * that queue into the socket Rx queue now */
239 if (call->rx_data_post == call->rx_first_oos) {
240 _debug("drain rx oos now");
241 read_lock(&call->state_lock);
242 if (call->state < RXRPC_CALL_COMPLETE &&
243 !test_and_set_bit(RXRPC_CALL_DRAIN_RX_OOS, &call->events))
David Howells651350d2007-04-26 15:50:17 -0700244 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700245 read_unlock(&call->state_lock);
246 }
247
248 spin_unlock(&call->lock);
249 atomic_inc(&call->ackr_not_idle);
250 rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, sp->hdr.serial, false);
251 _leave(" = 0 [posted]");
252 return 0;
253
254protocol_error:
255 ret = -EBADMSG;
256out:
257 spin_unlock(&call->lock);
258 _leave(" = %d", ret);
259 return ret;
260
261discard_and_ack:
262 _debug("discard and ACK packet %p", skb);
263 __rxrpc_propose_ACK(call, ack, sp->hdr.serial, true);
264discard:
265 spin_unlock(&call->lock);
266 rxrpc_free_skb(skb);
267 _leave(" = 0 [discarded]");
268 return 0;
269
270enqueue_and_ack:
271 __rxrpc_propose_ACK(call, ack, sp->hdr.serial, true);
272enqueue_packet:
273 _net("defer skb %p", skb);
274 spin_unlock(&call->lock);
275 skb_queue_tail(&call->rx_queue, skb);
276 atomic_inc(&call->ackr_not_idle);
277 read_lock(&call->state_lock);
278 if (call->state < RXRPC_CALL_DEAD)
David Howells651350d2007-04-26 15:50:17 -0700279 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700280 read_unlock(&call->state_lock);
281 _leave(" = 0 [queued]");
282 return 0;
283}
284
285/*
286 * assume an implicit ACKALL of the transmission phase of a client socket upon
287 * reception of the first reply packet
288 */
289static void rxrpc_assume_implicit_ackall(struct rxrpc_call *call, u32 serial)
290{
291 write_lock_bh(&call->state_lock);
292
293 switch (call->state) {
294 case RXRPC_CALL_CLIENT_AWAIT_REPLY:
295 call->state = RXRPC_CALL_CLIENT_RECV_REPLY;
296 call->acks_latest = serial;
297
298 _debug("implicit ACKALL %%%u", call->acks_latest);
299 set_bit(RXRPC_CALL_RCVD_ACKALL, &call->events);
300 write_unlock_bh(&call->state_lock);
301
302 if (try_to_del_timer_sync(&call->resend_timer) >= 0) {
303 clear_bit(RXRPC_CALL_RESEND_TIMER, &call->events);
304 clear_bit(RXRPC_CALL_RESEND, &call->events);
305 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
306 }
307 break;
308
309 default:
310 write_unlock_bh(&call->state_lock);
311 break;
312 }
313}
314
315/*
316 * post an incoming packet to the nominated call to deal with
317 * - must get rid of the sk_buff, either by freeing it or by queuing it
318 */
319void rxrpc_fast_process_packet(struct rxrpc_call *call, struct sk_buff *skb)
320{
321 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
322 __be32 _abort_code;
323 u32 serial, hi_serial, seq, abort_code;
324
325 _enter("%p,%p", call, skb);
326
327 ASSERT(!irqs_disabled());
328
329#if 0 // INJECT RX ERROR
330 if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA) {
331 static int skip = 0;
332 if (++skip == 3) {
333 printk("DROPPED 3RD PACKET!!!!!!!!!!!!!\n");
334 skip = 0;
335 goto free_packet;
336 }
337 }
338#endif
339
340 /* track the latest serial number on this connection for ACK packet
341 * information */
342 serial = ntohl(sp->hdr.serial);
343 hi_serial = atomic_read(&call->conn->hi_serial);
344 while (serial > hi_serial)
345 hi_serial = atomic_cmpxchg(&call->conn->hi_serial, hi_serial,
346 serial);
347
348 /* request ACK generation for any ACK or DATA packet that requests
349 * it */
350 if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
351 _proto("ACK Requested on %%%u", serial);
352 rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, sp->hdr.serial,
353 !(sp->hdr.flags & RXRPC_MORE_PACKETS));
354 }
355
356 switch (sp->hdr.type) {
357 case RXRPC_PACKET_TYPE_ABORT:
358 _debug("abort");
359
360 if (skb_copy_bits(skb, 0, &_abort_code,
361 sizeof(_abort_code)) < 0)
362 goto protocol_error;
363
364 abort_code = ntohl(_abort_code);
365 _proto("Rx ABORT %%%u { %x }", serial, abort_code);
366
367 write_lock_bh(&call->state_lock);
368 if (call->state < RXRPC_CALL_COMPLETE) {
369 call->state = RXRPC_CALL_REMOTELY_ABORTED;
370 call->abort_code = abort_code;
371 set_bit(RXRPC_CALL_RCVD_ABORT, &call->events);
David Howells651350d2007-04-26 15:50:17 -0700372 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700373 }
374 goto free_packet_unlock;
375
376 case RXRPC_PACKET_TYPE_BUSY:
377 _proto("Rx BUSY %%%u", serial);
378
379 if (call->conn->out_clientflag)
380 goto protocol_error;
381
382 write_lock_bh(&call->state_lock);
383 switch (call->state) {
384 case RXRPC_CALL_CLIENT_SEND_REQUEST:
385 call->state = RXRPC_CALL_SERVER_BUSY;
386 set_bit(RXRPC_CALL_RCVD_BUSY, &call->events);
David Howells651350d2007-04-26 15:50:17 -0700387 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700388 case RXRPC_CALL_SERVER_BUSY:
389 goto free_packet_unlock;
390 default:
391 goto protocol_error_locked;
392 }
393
394 default:
395 _proto("Rx %s %%%u", rxrpc_pkts[sp->hdr.type], serial);
396 goto protocol_error;
397
398 case RXRPC_PACKET_TYPE_DATA:
399 seq = ntohl(sp->hdr.seq);
400
401 _proto("Rx DATA %%%u { #%u }", serial, seq);
402
403 if (seq == 0)
404 goto protocol_error;
405
406 call->ackr_prev_seq = sp->hdr.seq;
407
408 /* received data implicitly ACKs all of the request packets we
409 * sent when we're acting as a client */
410 if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY)
411 rxrpc_assume_implicit_ackall(call, serial);
412
413 switch (rxrpc_fast_process_data(call, skb, seq)) {
414 case 0:
415 skb = NULL;
416 goto done;
417
418 default:
419 BUG();
420
421 /* data packet received beyond the last packet */
422 case -EBADMSG:
423 goto protocol_error;
424 }
425
426 case RXRPC_PACKET_TYPE_ACK:
427 /* ACK processing is done in process context */
428 read_lock_bh(&call->state_lock);
429 if (call->state < RXRPC_CALL_DEAD) {
430 skb_queue_tail(&call->rx_queue, skb);
David Howells651350d2007-04-26 15:50:17 -0700431 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700432 skb = NULL;
433 }
434 read_unlock_bh(&call->state_lock);
435 goto free_packet;
436 }
437
438protocol_error:
439 _debug("protocol error");
440 write_lock_bh(&call->state_lock);
441protocol_error_locked:
442 if (call->state <= RXRPC_CALL_COMPLETE) {
443 call->state = RXRPC_CALL_LOCALLY_ABORTED;
444 call->abort_code = RX_PROTOCOL_ERROR;
445 set_bit(RXRPC_CALL_ABORT, &call->events);
David Howells651350d2007-04-26 15:50:17 -0700446 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700447 }
448free_packet_unlock:
449 write_unlock_bh(&call->state_lock);
450free_packet:
451 rxrpc_free_skb(skb);
452done:
453 _leave("");
454}
455
456/*
457 * split up a jumbo data packet
458 */
459static void rxrpc_process_jumbo_packet(struct rxrpc_call *call,
460 struct sk_buff *jumbo)
461{
462 struct rxrpc_jumbo_header jhdr;
463 struct rxrpc_skb_priv *sp;
464 struct sk_buff *part;
465
466 _enter(",{%u,%u}", jumbo->data_len, jumbo->len);
467
468 sp = rxrpc_skb(jumbo);
469
470 do {
471 sp->hdr.flags &= ~RXRPC_JUMBO_PACKET;
472
473 /* make a clone to represent the first subpacket in what's left
474 * of the jumbo packet */
475 part = skb_clone(jumbo, GFP_ATOMIC);
476 if (!part) {
477 /* simply ditch the tail in the event of ENOMEM */
478 pskb_trim(jumbo, RXRPC_JUMBO_DATALEN);
479 break;
480 }
481 rxrpc_new_skb(part);
482
483 pskb_trim(part, RXRPC_JUMBO_DATALEN);
484
485 if (!pskb_pull(jumbo, RXRPC_JUMBO_DATALEN))
486 goto protocol_error;
487
488 if (skb_copy_bits(jumbo, 0, &jhdr, sizeof(jhdr)) < 0)
489 goto protocol_error;
490 if (!pskb_pull(jumbo, sizeof(jhdr)))
491 BUG();
492
493 sp->hdr.seq = htonl(ntohl(sp->hdr.seq) + 1);
494 sp->hdr.serial = htonl(ntohl(sp->hdr.serial) + 1);
495 sp->hdr.flags = jhdr.flags;
496 sp->hdr._rsvd = jhdr._rsvd;
497
498 _proto("Rx DATA Jumbo %%%u", ntohl(sp->hdr.serial) - 1);
499
500 rxrpc_fast_process_packet(call, part);
501 part = NULL;
502
503 } while (sp->hdr.flags & RXRPC_JUMBO_PACKET);
504
505 rxrpc_fast_process_packet(call, jumbo);
506 _leave("");
507 return;
508
509protocol_error:
510 _debug("protocol error");
511 rxrpc_free_skb(part);
512 rxrpc_free_skb(jumbo);
513 write_lock_bh(&call->state_lock);
514 if (call->state <= RXRPC_CALL_COMPLETE) {
515 call->state = RXRPC_CALL_LOCALLY_ABORTED;
516 call->abort_code = RX_PROTOCOL_ERROR;
517 set_bit(RXRPC_CALL_ABORT, &call->events);
David Howells651350d2007-04-26 15:50:17 -0700518 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700519 }
520 write_unlock_bh(&call->state_lock);
521 _leave("");
522}
523
524/*
525 * post an incoming packet to the appropriate call/socket to deal with
526 * - must get rid of the sk_buff, either by freeing it or by queuing it
527 */
528static void rxrpc_post_packet_to_call(struct rxrpc_connection *conn,
529 struct sk_buff *skb)
530{
531 struct rxrpc_skb_priv *sp;
532 struct rxrpc_call *call;
533 struct rb_node *p;
534 __be32 call_id;
535
536 _enter("%p,%p", conn, skb);
537
538 read_lock_bh(&conn->lock);
539
540 sp = rxrpc_skb(skb);
541
542 /* look at extant calls by channel number first */
543 call = conn->channels[ntohl(sp->hdr.cid) & RXRPC_CHANNELMASK];
544 if (!call || call->call_id != sp->hdr.callNumber)
545 goto call_not_extant;
546
547 _debug("extant call [%d]", call->state);
548 ASSERTCMP(call->conn, ==, conn);
549
550 read_lock(&call->state_lock);
551 switch (call->state) {
552 case RXRPC_CALL_LOCALLY_ABORTED:
553 if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
David Howells651350d2007-04-26 15:50:17 -0700554 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700555 case RXRPC_CALL_REMOTELY_ABORTED:
556 case RXRPC_CALL_NETWORK_ERROR:
557 case RXRPC_CALL_DEAD:
558 goto free_unlock;
559 default:
560 break;
561 }
562
563 read_unlock(&call->state_lock);
564 rxrpc_get_call(call);
565 read_unlock_bh(&conn->lock);
566
567 if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
568 sp->hdr.flags & RXRPC_JUMBO_PACKET)
569 rxrpc_process_jumbo_packet(call, skb);
570 else
571 rxrpc_fast_process_packet(call, skb);
572
573 rxrpc_put_call(call);
574 goto done;
575
576call_not_extant:
577 /* search the completed calls in case what we're dealing with is
578 * there */
579 _debug("call not extant");
580
581 call_id = sp->hdr.callNumber;
582 p = conn->calls.rb_node;
583 while (p) {
584 call = rb_entry(p, struct rxrpc_call, conn_node);
585
586 if (call_id < call->call_id)
587 p = p->rb_left;
588 else if (call_id > call->call_id)
589 p = p->rb_right;
590 else
591 goto found_completed_call;
592 }
593
594dead_call:
595 /* it's a either a really old call that we no longer remember or its a
596 * new incoming call */
597 read_unlock_bh(&conn->lock);
598
599 if (sp->hdr.flags & RXRPC_CLIENT_INITIATED &&
YOSHIFUJI Hideakiae445d12007-12-12 03:55:22 +0900600 sp->hdr.seq == cpu_to_be32(1)) {
David Howells17926a72007-04-26 15:48:28 -0700601 _debug("incoming call");
602 skb_queue_tail(&conn->trans->local->accept_queue, skb);
David Howells651350d2007-04-26 15:50:17 -0700603 rxrpc_queue_work(&conn->trans->local->acceptor);
David Howells17926a72007-04-26 15:48:28 -0700604 goto done;
605 }
606
607 _debug("dead call");
608 skb->priority = RX_CALL_DEAD;
609 rxrpc_reject_packet(conn->trans->local, skb);
610 goto done;
611
612 /* resend last packet of a completed call
613 * - client calls may have been aborted or ACK'd
614 * - server calls may have been aborted
615 */
616found_completed_call:
617 _debug("completed call");
618
619 if (atomic_read(&call->usage) == 0)
620 goto dead_call;
621
622 /* synchronise any state changes */
623 read_lock(&call->state_lock);
624 ASSERTIFCMP(call->state != RXRPC_CALL_CLIENT_FINAL_ACK,
625 call->state, >=, RXRPC_CALL_COMPLETE);
626
627 if (call->state == RXRPC_CALL_LOCALLY_ABORTED ||
628 call->state == RXRPC_CALL_REMOTELY_ABORTED ||
629 call->state == RXRPC_CALL_DEAD) {
630 read_unlock(&call->state_lock);
631 goto dead_call;
632 }
633
634 if (call->conn->in_clientflag) {
635 read_unlock(&call->state_lock);
636 goto dead_call; /* complete server call */
637 }
638
639 _debug("final ack again");
640 rxrpc_get_call(call);
641 set_bit(RXRPC_CALL_ACK_FINAL, &call->events);
David Howells651350d2007-04-26 15:50:17 -0700642 rxrpc_queue_call(call);
David Howells17926a72007-04-26 15:48:28 -0700643
644free_unlock:
645 read_unlock(&call->state_lock);
646 read_unlock_bh(&conn->lock);
647 rxrpc_free_skb(skb);
648done:
649 _leave("");
650}
651
652/*
653 * post connection-level events to the connection
654 * - this includes challenges, responses and some aborts
655 */
656static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
657 struct sk_buff *skb)
658{
659 _enter("%p,%p", conn, skb);
660
661 atomic_inc(&conn->usage);
662 skb_queue_tail(&conn->rx_queue, skb);
David Howells651350d2007-04-26 15:50:17 -0700663 rxrpc_queue_conn(conn);
David Howells17926a72007-04-26 15:48:28 -0700664}
665
666/*
667 * handle data received on the local endpoint
668 * - may be called in interrupt context
669 */
670void rxrpc_data_ready(struct sock *sk, int count)
671{
672 struct rxrpc_connection *conn;
673 struct rxrpc_transport *trans;
674 struct rxrpc_skb_priv *sp;
675 struct rxrpc_local *local;
676 struct rxrpc_peer *peer;
677 struct sk_buff *skb;
678 int ret;
679
680 _enter("%p, %d", sk, count);
681
682 ASSERT(!irqs_disabled());
683
684 read_lock_bh(&rxrpc_local_lock);
685 local = sk->sk_user_data;
686 if (local && atomic_read(&local->usage) > 0)
687 rxrpc_get_local(local);
688 else
689 local = NULL;
690 read_unlock_bh(&rxrpc_local_lock);
691 if (!local) {
692 _leave(" [local dead]");
693 return;
694 }
695
696 skb = skb_recv_datagram(sk, 0, 1, &ret);
697 if (!skb) {
698 rxrpc_put_local(local);
699 if (ret == -EAGAIN)
700 return;
701 _debug("UDP socket error %d", ret);
702 return;
703 }
704
705 rxrpc_new_skb(skb);
706
707 _net("recv skb %p", skb);
708
709 /* we'll probably need to checksum it (didn't call sock_recvmsg) */
710 if (skb_checksum_complete(skb)) {
711 rxrpc_free_skb(skb);
712 rxrpc_put_local(local);
Pavel Emelyanov02833282008-07-05 21:18:48 -0700713 UDP_INC_STATS_BH(&init_net, UDP_MIB_INERRORS, 0);
David Howells17926a72007-04-26 15:48:28 -0700714 _leave(" [CSUM failed]");
715 return;
716 }
717
Pavel Emelyanov02833282008-07-05 21:18:48 -0700718 UDP_INC_STATS_BH(&init_net, UDP_MIB_INDATAGRAMS, 0);
Herbert Xu1781f7f2007-12-11 11:30:32 -0800719
David Howells17926a72007-04-26 15:48:28 -0700720 /* the socket buffer we have is owned by UDP, with UDP's data all over
721 * it, but we really want our own */
722 skb_orphan(skb);
723 sp = rxrpc_skb(skb);
724 memset(sp, 0, sizeof(*sp));
725
726 _net("Rx UDP packet from %08x:%04hu",
727 ntohl(ip_hdr(skb)->saddr), ntohs(udp_hdr(skb)->source));
728
729 /* dig out the RxRPC connection details */
730 if (skb_copy_bits(skb, sizeof(struct udphdr), &sp->hdr,
731 sizeof(sp->hdr)) < 0)
732 goto bad_message;
733 if (!pskb_pull(skb, sizeof(struct udphdr) + sizeof(sp->hdr)))
734 BUG();
735
736 _net("Rx RxRPC %s ep=%x call=%x:%x",
737 sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient",
738 ntohl(sp->hdr.epoch),
739 ntohl(sp->hdr.cid),
740 ntohl(sp->hdr.callNumber));
741
742 if (sp->hdr.type == 0 || sp->hdr.type >= RXRPC_N_PACKET_TYPES) {
743 _proto("Rx Bad Packet Type %u", sp->hdr.type);
744 goto bad_message;
745 }
746
747 if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
748 (sp->hdr.callNumber == 0 || sp->hdr.seq == 0))
749 goto bad_message;
750
751 peer = rxrpc_find_peer(local, ip_hdr(skb)->saddr, udp_hdr(skb)->source);
752 if (IS_ERR(peer))
753 goto cant_route_call;
754
755 trans = rxrpc_find_transport(local, peer);
756 rxrpc_put_peer(peer);
757 if (!trans)
758 goto cant_route_call;
759
760 conn = rxrpc_find_connection(trans, &sp->hdr);
761 rxrpc_put_transport(trans);
762 if (!conn)
763 goto cant_route_call;
764
765 _debug("CONN %p {%d}", conn, conn->debug_id);
766
767 if (sp->hdr.callNumber == 0)
768 rxrpc_post_packet_to_conn(conn, skb);
769 else
770 rxrpc_post_packet_to_call(conn, skb);
771 rxrpc_put_connection(conn);
772 rxrpc_put_local(local);
773 return;
774
775cant_route_call:
776 _debug("can't route call");
777 if (sp->hdr.flags & RXRPC_CLIENT_INITIATED &&
778 sp->hdr.type == RXRPC_PACKET_TYPE_DATA) {
YOSHIFUJI Hideakiae445d12007-12-12 03:55:22 +0900779 if (sp->hdr.seq == cpu_to_be32(1)) {
David Howells17926a72007-04-26 15:48:28 -0700780 _debug("first packet");
781 skb_queue_tail(&local->accept_queue, skb);
David Howells651350d2007-04-26 15:50:17 -0700782 rxrpc_queue_work(&local->acceptor);
David Howells17926a72007-04-26 15:48:28 -0700783 rxrpc_put_local(local);
784 _leave(" [incoming]");
785 return;
786 }
787 skb->priority = RX_INVALID_OPERATION;
788 } else {
789 skb->priority = RX_CALL_DEAD;
790 }
791
792 _debug("reject");
793 rxrpc_reject_packet(local, skb);
794 rxrpc_put_local(local);
795 _leave(" [no call]");
796 return;
797
798bad_message:
799 skb->priority = RX_PROTOCOL_ERROR;
800 rxrpc_reject_packet(local, skb);
801 rxrpc_put_local(local);
802 _leave(" [badmsg]");
803}