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-rw-r--r--net/rxrpc/ar-input.c791
1 files changed, 791 insertions, 0 deletions
diff --git a/net/rxrpc/ar-input.c b/net/rxrpc/ar-input.c
new file mode 100644
index 000000000000..323c3454561c
--- /dev/null
+++ b/net/rxrpc/ar-input.c
@@ -0,0 +1,791 @@
1/* 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>
20#include <net/sock.h>
21#include <net/af_rxrpc.h>
22#include <net/ip.h>
23#include "ar-internal.h"
24
25unsigned long rxrpc_ack_timeout = 1;
26
27const char *rxrpc_pkts[] = {
28 "?00",
29 "DATA", "ACK", "BUSY", "ABORT", "ACKALL", "CHALL", "RESP", "DEBUG",
30 "?09", "?10", "?11", "?12", "?13", "?14", "?15"
31};
32
33/*
34 * queue a packet for recvmsg to pass to userspace
35 * - the caller must hold a lock on call->lock
36 * - must not be called with interrupts disabled (sk_filter() disables BH's)
37 * - eats the packet whether successful or not
38 * - there must be just one reference to the packet, which the caller passes to
39 * this function
40 */
41int rxrpc_queue_rcv_skb(struct rxrpc_call *call, struct sk_buff *skb,
42 bool force, bool terminal)
43{
44 struct rxrpc_skb_priv *sp;
45 struct sock *sk;
46 int skb_len, ret;
47
48 _enter(",,%d,%d", force, terminal);
49
50 ASSERT(!irqs_disabled());
51
52 sp = rxrpc_skb(skb);
53 ASSERTCMP(sp->call, ==, call);
54
55 /* if we've already posted the terminal message for a call, then we
56 * don't post any more */
57 if (test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) {
58 _debug("already terminated");
59 ASSERTCMP(call->state, >=, RXRPC_CALL_COMPLETE);
60 skb->destructor = NULL;
61 sp->call = NULL;
62 rxrpc_put_call(call);
63 rxrpc_free_skb(skb);
64 return 0;
65 }
66
67 sk = &call->socket->sk;
68
69 if (!force) {
70 /* cast skb->rcvbuf to unsigned... It's pointless, but
71 * reduces number of warnings when compiling with -W
72 * --ANK */
73// ret = -ENOBUFS;
74// if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
75// (unsigned) sk->sk_rcvbuf)
76// goto out;
77
78 ret = sk_filter(sk, skb);
79 if (ret < 0)
80 goto out;
81 }
82
83 spin_lock_bh(&sk->sk_receive_queue.lock);
84 if (!test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags) &&
85 !test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
86 call->socket->sk.sk_state != RXRPC_CLOSE) {
87 skb->destructor = rxrpc_packet_destructor;
88 skb->dev = NULL;
89 skb->sk = sk;
90 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
91
92 /* Cache the SKB length before we tack it onto the receive
93 * queue. Once it is added it no longer belongs to us and
94 * may be freed by other threads of control pulling packets
95 * from the queue.
96 */
97 skb_len = skb->len;
98
99 _net("post skb %p", skb);
100 __skb_queue_tail(&sk->sk_receive_queue, skb);
101 spin_unlock_bh(&sk->sk_receive_queue.lock);
102
103 if (!sock_flag(sk, SOCK_DEAD))
104 sk->sk_data_ready(sk, skb_len);
105
106 if (terminal) {
107 _debug("<<<< TERMINAL MESSAGE >>>>");
108 set_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags);
109 }
110
111 skb = NULL;
112 } else {
113 spin_unlock_bh(&sk->sk_receive_queue.lock);
114 }
115 ret = 0;
116
117out:
118 /* release the socket buffer */
119 if (skb) {
120 skb->destructor = NULL;
121 sp->call = NULL;
122 rxrpc_put_call(call);
123 rxrpc_free_skb(skb);
124 }
125
126 _leave(" = %d", ret);
127 return ret;
128}
129
130/*
131 * process a DATA packet, posting the packet to the appropriate queue
132 * - eats the packet if successful
133 */
134static int rxrpc_fast_process_data(struct rxrpc_call *call,
135 struct sk_buff *skb, u32 seq)
136{
137 struct rxrpc_skb_priv *sp;
138 bool terminal;
139 int ret, ackbit, ack;
140
141 _enter("{%u,%u},,{%u}", call->rx_data_post, call->rx_first_oos, seq);
142
143 sp = rxrpc_skb(skb);
144 ASSERTCMP(sp->call, ==, NULL);
145
146 spin_lock(&call->lock);
147
148 if (call->state > RXRPC_CALL_COMPLETE)
149 goto discard;
150
151 ASSERTCMP(call->rx_data_expect, >=, call->rx_data_post);
152 ASSERTCMP(call->rx_data_post, >=, call->rx_data_recv);
153 ASSERTCMP(call->rx_data_recv, >=, call->rx_data_eaten);
154
155 if (seq < call->rx_data_post) {
156 _debug("dup #%u [-%u]", seq, call->rx_data_post);
157 ack = RXRPC_ACK_DUPLICATE;
158 ret = -ENOBUFS;
159 goto discard_and_ack;
160 }
161
162 /* we may already have the packet in the out of sequence queue */
163 ackbit = seq - (call->rx_data_eaten + 1);
164 ASSERTCMP(ackbit, >=, 0);
165 if (__test_and_set_bit(ackbit, &call->ackr_window)) {
166 _debug("dup oos #%u [%u,%u]",
167 seq, call->rx_data_eaten, call->rx_data_post);
168 ack = RXRPC_ACK_DUPLICATE;
169 goto discard_and_ack;
170 }
171
172 if (seq >= call->ackr_win_top) {
173 _debug("exceed #%u [%u]", seq, call->ackr_win_top);
174 __clear_bit(ackbit, &call->ackr_window);
175 ack = RXRPC_ACK_EXCEEDS_WINDOW;
176 goto discard_and_ack;
177 }
178
179 if (seq == call->rx_data_expect) {
180 clear_bit(RXRPC_CALL_EXPECT_OOS, &call->flags);
181 call->rx_data_expect++;
182 } else if (seq > call->rx_data_expect) {
183 _debug("oos #%u [%u]", seq, call->rx_data_expect);
184 call->rx_data_expect = seq + 1;
185 if (test_and_set_bit(RXRPC_CALL_EXPECT_OOS, &call->flags)) {
186 ack = RXRPC_ACK_OUT_OF_SEQUENCE;
187 goto enqueue_and_ack;
188 }
189 goto enqueue_packet;
190 }
191
192 if (seq != call->rx_data_post) {
193 _debug("ahead #%u [%u]", seq, call->rx_data_post);
194 goto enqueue_packet;
195 }
196
197 if (test_bit(RXRPC_CALL_RCVD_LAST, &call->flags))
198 goto protocol_error;
199
200 /* if the packet need security things doing to it, then it goes down
201 * the slow path */
202 if (call->conn->security)
203 goto enqueue_packet;
204
205 sp->call = call;
206 rxrpc_get_call(call);
207 terminal = ((sp->hdr.flags & RXRPC_LAST_PACKET) &&
208 !(sp->hdr.flags & RXRPC_CLIENT_INITIATED));
209 ret = rxrpc_queue_rcv_skb(call, skb, false, terminal);
210 if (ret < 0) {
211 if (ret == -ENOMEM || ret == -ENOBUFS) {
212 __clear_bit(ackbit, &call->ackr_window);
213 ack = RXRPC_ACK_NOSPACE;
214 goto discard_and_ack;
215 }
216 goto out;
217 }
218
219 skb = NULL;
220
221 _debug("post #%u", seq);
222 ASSERTCMP(call->rx_data_post, ==, seq);
223 call->rx_data_post++;
224
225 if (sp->hdr.flags & RXRPC_LAST_PACKET)
226 set_bit(RXRPC_CALL_RCVD_LAST, &call->flags);
227
228 /* if we've reached an out of sequence packet then we need to drain
229 * that queue into the socket Rx queue now */
230 if (call->rx_data_post == call->rx_first_oos) {
231 _debug("drain rx oos now");
232 read_lock(&call->state_lock);
233 if (call->state < RXRPC_CALL_COMPLETE &&
234 !test_and_set_bit(RXRPC_CALL_DRAIN_RX_OOS, &call->events))
235 schedule_work(&call->processor);
236 read_unlock(&call->state_lock);
237 }
238
239 spin_unlock(&call->lock);
240 atomic_inc(&call->ackr_not_idle);
241 rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, sp->hdr.serial, false);
242 _leave(" = 0 [posted]");
243 return 0;
244
245protocol_error:
246 ret = -EBADMSG;
247out:
248 spin_unlock(&call->lock);
249 _leave(" = %d", ret);
250 return ret;
251
252discard_and_ack:
253 _debug("discard and ACK packet %p", skb);
254 __rxrpc_propose_ACK(call, ack, sp->hdr.serial, true);
255discard:
256 spin_unlock(&call->lock);
257 rxrpc_free_skb(skb);
258 _leave(" = 0 [discarded]");
259 return 0;
260
261enqueue_and_ack:
262 __rxrpc_propose_ACK(call, ack, sp->hdr.serial, true);
263enqueue_packet:
264 _net("defer skb %p", skb);
265 spin_unlock(&call->lock);
266 skb_queue_tail(&call->rx_queue, skb);
267 atomic_inc(&call->ackr_not_idle);
268 read_lock(&call->state_lock);
269 if (call->state < RXRPC_CALL_DEAD)
270 schedule_work(&call->processor);
271 read_unlock(&call->state_lock);
272 _leave(" = 0 [queued]");
273 return 0;
274}
275
276/*
277 * assume an implicit ACKALL of the transmission phase of a client socket upon
278 * reception of the first reply packet
279 */
280static void rxrpc_assume_implicit_ackall(struct rxrpc_call *call, u32 serial)
281{
282 write_lock_bh(&call->state_lock);
283
284 switch (call->state) {
285 case RXRPC_CALL_CLIENT_AWAIT_REPLY:
286 call->state = RXRPC_CALL_CLIENT_RECV_REPLY;
287 call->acks_latest = serial;
288
289 _debug("implicit ACKALL %%%u", call->acks_latest);
290 set_bit(RXRPC_CALL_RCVD_ACKALL, &call->events);
291 write_unlock_bh(&call->state_lock);
292
293 if (try_to_del_timer_sync(&call->resend_timer) >= 0) {
294 clear_bit(RXRPC_CALL_RESEND_TIMER, &call->events);
295 clear_bit(RXRPC_CALL_RESEND, &call->events);
296 clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
297 }
298 break;
299
300 default:
301 write_unlock_bh(&call->state_lock);
302 break;
303 }
304}
305
306/*
307 * post an incoming packet to the nominated call to deal with
308 * - must get rid of the sk_buff, either by freeing it or by queuing it
309 */
310void rxrpc_fast_process_packet(struct rxrpc_call *call, struct sk_buff *skb)
311{
312 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
313 __be32 _abort_code;
314 u32 serial, hi_serial, seq, abort_code;
315
316 _enter("%p,%p", call, skb);
317
318 ASSERT(!irqs_disabled());
319
320#if 0 // INJECT RX ERROR
321 if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA) {
322 static int skip = 0;
323 if (++skip == 3) {
324 printk("DROPPED 3RD PACKET!!!!!!!!!!!!!\n");
325 skip = 0;
326 goto free_packet;
327 }
328 }
329#endif
330
331 /* track the latest serial number on this connection for ACK packet
332 * information */
333 serial = ntohl(sp->hdr.serial);
334 hi_serial = atomic_read(&call->conn->hi_serial);
335 while (serial > hi_serial)
336 hi_serial = atomic_cmpxchg(&call->conn->hi_serial, hi_serial,
337 serial);
338
339 /* request ACK generation for any ACK or DATA packet that requests
340 * it */
341 if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
342 _proto("ACK Requested on %%%u", serial);
343 rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED, sp->hdr.serial,
344 !(sp->hdr.flags & RXRPC_MORE_PACKETS));
345 }
346
347 switch (sp->hdr.type) {
348 case RXRPC_PACKET_TYPE_ABORT:
349 _debug("abort");
350
351 if (skb_copy_bits(skb, 0, &_abort_code,
352 sizeof(_abort_code)) < 0)
353 goto protocol_error;
354
355 abort_code = ntohl(_abort_code);
356 _proto("Rx ABORT %%%u { %x }", serial, abort_code);
357
358 write_lock_bh(&call->state_lock);
359 if (call->state < RXRPC_CALL_COMPLETE) {
360 call->state = RXRPC_CALL_REMOTELY_ABORTED;
361 call->abort_code = abort_code;
362 set_bit(RXRPC_CALL_RCVD_ABORT, &call->events);
363 schedule_work(&call->processor);
364 }
365 goto free_packet_unlock;
366
367 case RXRPC_PACKET_TYPE_BUSY:
368 _proto("Rx BUSY %%%u", serial);
369
370 if (call->conn->out_clientflag)
371 goto protocol_error;
372
373 write_lock_bh(&call->state_lock);
374 switch (call->state) {
375 case RXRPC_CALL_CLIENT_SEND_REQUEST:
376 call->state = RXRPC_CALL_SERVER_BUSY;
377 set_bit(RXRPC_CALL_RCVD_BUSY, &call->events);
378 schedule_work(&call->processor);
379 case RXRPC_CALL_SERVER_BUSY:
380 goto free_packet_unlock;
381 default:
382 goto protocol_error_locked;
383 }
384
385 default:
386 _proto("Rx %s %%%u", rxrpc_pkts[sp->hdr.type], serial);
387 goto protocol_error;
388
389 case RXRPC_PACKET_TYPE_DATA:
390 seq = ntohl(sp->hdr.seq);
391
392 _proto("Rx DATA %%%u { #%u }", serial, seq);
393
394 if (seq == 0)
395 goto protocol_error;
396
397 call->ackr_prev_seq = sp->hdr.seq;
398
399 /* received data implicitly ACKs all of the request packets we
400 * sent when we're acting as a client */
401 if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY)
402 rxrpc_assume_implicit_ackall(call, serial);
403
404 switch (rxrpc_fast_process_data(call, skb, seq)) {
405 case 0:
406 skb = NULL;
407 goto done;
408
409 default:
410 BUG();
411
412 /* data packet received beyond the last packet */
413 case -EBADMSG:
414 goto protocol_error;
415 }
416
417 case RXRPC_PACKET_TYPE_ACK:
418 /* ACK processing is done in process context */
419 read_lock_bh(&call->state_lock);
420 if (call->state < RXRPC_CALL_DEAD) {
421 skb_queue_tail(&call->rx_queue, skb);
422 schedule_work(&call->processor);
423 skb = NULL;
424 }
425 read_unlock_bh(&call->state_lock);
426 goto free_packet;
427 }
428
429protocol_error:
430 _debug("protocol error");
431 write_lock_bh(&call->state_lock);
432protocol_error_locked:
433 if (call->state <= RXRPC_CALL_COMPLETE) {
434 call->state = RXRPC_CALL_LOCALLY_ABORTED;
435 call->abort_code = RX_PROTOCOL_ERROR;
436 set_bit(RXRPC_CALL_ABORT, &call->events);
437 schedule_work(&call->processor);
438 }
439free_packet_unlock:
440 write_unlock_bh(&call->state_lock);
441free_packet:
442 rxrpc_free_skb(skb);
443done:
444 _leave("");
445}
446
447/*
448 * split up a jumbo data packet
449 */
450static void rxrpc_process_jumbo_packet(struct rxrpc_call *call,
451 struct sk_buff *jumbo)
452{
453 struct rxrpc_jumbo_header jhdr;
454 struct rxrpc_skb_priv *sp;
455 struct sk_buff *part;
456
457 _enter(",{%u,%u}", jumbo->data_len, jumbo->len);
458
459 sp = rxrpc_skb(jumbo);
460
461 do {
462 sp->hdr.flags &= ~RXRPC_JUMBO_PACKET;
463
464 /* make a clone to represent the first subpacket in what's left
465 * of the jumbo packet */
466 part = skb_clone(jumbo, GFP_ATOMIC);
467 if (!part) {
468 /* simply ditch the tail in the event of ENOMEM */
469 pskb_trim(jumbo, RXRPC_JUMBO_DATALEN);
470 break;
471 }
472 rxrpc_new_skb(part);
473
474 pskb_trim(part, RXRPC_JUMBO_DATALEN);
475
476 if (!pskb_pull(jumbo, RXRPC_JUMBO_DATALEN))
477 goto protocol_error;
478
479 if (skb_copy_bits(jumbo, 0, &jhdr, sizeof(jhdr)) < 0)
480 goto protocol_error;
481 if (!pskb_pull(jumbo, sizeof(jhdr)))
482 BUG();
483
484 sp->hdr.seq = htonl(ntohl(sp->hdr.seq) + 1);
485 sp->hdr.serial = htonl(ntohl(sp->hdr.serial) + 1);
486 sp->hdr.flags = jhdr.flags;
487 sp->hdr._rsvd = jhdr._rsvd;
488
489 _proto("Rx DATA Jumbo %%%u", ntohl(sp->hdr.serial) - 1);
490
491 rxrpc_fast_process_packet(call, part);
492 part = NULL;
493
494 } while (sp->hdr.flags & RXRPC_JUMBO_PACKET);
495
496 rxrpc_fast_process_packet(call, jumbo);
497 _leave("");
498 return;
499
500protocol_error:
501 _debug("protocol error");
502 rxrpc_free_skb(part);
503 rxrpc_free_skb(jumbo);
504 write_lock_bh(&call->state_lock);
505 if (call->state <= RXRPC_CALL_COMPLETE) {
506 call->state = RXRPC_CALL_LOCALLY_ABORTED;
507 call->abort_code = RX_PROTOCOL_ERROR;
508 set_bit(RXRPC_CALL_ABORT, &call->events);
509 schedule_work(&call->processor);
510 }
511 write_unlock_bh(&call->state_lock);
512 _leave("");
513}
514
515/*
516 * post an incoming packet to the appropriate call/socket to deal with
517 * - must get rid of the sk_buff, either by freeing it or by queuing it
518 */
519static void rxrpc_post_packet_to_call(struct rxrpc_connection *conn,
520 struct sk_buff *skb)
521{
522 struct rxrpc_skb_priv *sp;
523 struct rxrpc_call *call;
524 struct rb_node *p;
525 __be32 call_id;
526
527 _enter("%p,%p", conn, skb);
528
529 read_lock_bh(&conn->lock);
530
531 sp = rxrpc_skb(skb);
532
533 /* look at extant calls by channel number first */
534 call = conn->channels[ntohl(sp->hdr.cid) & RXRPC_CHANNELMASK];
535 if (!call || call->call_id != sp->hdr.callNumber)
536 goto call_not_extant;
537
538 _debug("extant call [%d]", call->state);
539 ASSERTCMP(call->conn, ==, conn);
540
541 read_lock(&call->state_lock);
542 switch (call->state) {
543 case RXRPC_CALL_LOCALLY_ABORTED:
544 if (!test_and_set_bit(RXRPC_CALL_ABORT, &call->events))
545 schedule_work(&call->processor);
546 case RXRPC_CALL_REMOTELY_ABORTED:
547 case RXRPC_CALL_NETWORK_ERROR:
548 case RXRPC_CALL_DEAD:
549 goto free_unlock;
550 default:
551 break;
552 }
553
554 read_unlock(&call->state_lock);
555 rxrpc_get_call(call);
556 read_unlock_bh(&conn->lock);
557
558 if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
559 sp->hdr.flags & RXRPC_JUMBO_PACKET)
560 rxrpc_process_jumbo_packet(call, skb);
561 else
562 rxrpc_fast_process_packet(call, skb);
563
564 rxrpc_put_call(call);
565 goto done;
566
567call_not_extant:
568 /* search the completed calls in case what we're dealing with is
569 * there */
570 _debug("call not extant");
571
572 call_id = sp->hdr.callNumber;
573 p = conn->calls.rb_node;
574 while (p) {
575 call = rb_entry(p, struct rxrpc_call, conn_node);
576
577 if (call_id < call->call_id)
578 p = p->rb_left;
579 else if (call_id > call->call_id)
580 p = p->rb_right;
581 else
582 goto found_completed_call;
583 }
584
585dead_call:
586 /* it's a either a really old call that we no longer remember or its a
587 * new incoming call */
588 read_unlock_bh(&conn->lock);
589
590 if (sp->hdr.flags & RXRPC_CLIENT_INITIATED &&
591 sp->hdr.seq == __constant_cpu_to_be32(1)) {
592 _debug("incoming call");
593 skb_queue_tail(&conn->trans->local->accept_queue, skb);
594 schedule_work(&conn->trans->local->acceptor);
595 goto done;
596 }
597
598 _debug("dead call");
599 skb->priority = RX_CALL_DEAD;
600 rxrpc_reject_packet(conn->trans->local, skb);
601 goto done;
602
603 /* resend last packet of a completed call
604 * - client calls may have been aborted or ACK'd
605 * - server calls may have been aborted
606 */
607found_completed_call:
608 _debug("completed call");
609
610 if (atomic_read(&call->usage) == 0)
611 goto dead_call;
612
613 /* synchronise any state changes */
614 read_lock(&call->state_lock);
615 ASSERTIFCMP(call->state != RXRPC_CALL_CLIENT_FINAL_ACK,
616 call->state, >=, RXRPC_CALL_COMPLETE);
617
618 if (call->state == RXRPC_CALL_LOCALLY_ABORTED ||
619 call->state == RXRPC_CALL_REMOTELY_ABORTED ||
620 call->state == RXRPC_CALL_DEAD) {
621 read_unlock(&call->state_lock);
622 goto dead_call;
623 }
624
625 if (call->conn->in_clientflag) {
626 read_unlock(&call->state_lock);
627 goto dead_call; /* complete server call */
628 }
629
630 _debug("final ack again");
631 rxrpc_get_call(call);
632 set_bit(RXRPC_CALL_ACK_FINAL, &call->events);
633 schedule_work(&call->processor);
634
635free_unlock:
636 read_unlock(&call->state_lock);
637 read_unlock_bh(&conn->lock);
638 rxrpc_free_skb(skb);
639done:
640 _leave("");
641}
642
643/*
644 * post connection-level events to the connection
645 * - this includes challenges, responses and some aborts
646 */
647static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
648 struct sk_buff *skb)
649{
650 _enter("%p,%p", conn, skb);
651
652 atomic_inc(&conn->usage);
653 skb_queue_tail(&conn->rx_queue, skb);
654 schedule_work(&conn->processor);
655}
656
657/*
658 * handle data received on the local endpoint
659 * - may be called in interrupt context
660 */
661void rxrpc_data_ready(struct sock *sk, int count)
662{
663 struct rxrpc_connection *conn;
664 struct rxrpc_transport *trans;
665 struct rxrpc_skb_priv *sp;
666 struct rxrpc_local *local;
667 struct rxrpc_peer *peer;
668 struct sk_buff *skb;
669 int ret;
670
671 _enter("%p, %d", sk, count);
672
673 ASSERT(!irqs_disabled());
674
675 read_lock_bh(&rxrpc_local_lock);
676 local = sk->sk_user_data;
677 if (local && atomic_read(&local->usage) > 0)
678 rxrpc_get_local(local);
679 else
680 local = NULL;
681 read_unlock_bh(&rxrpc_local_lock);
682 if (!local) {
683 _leave(" [local dead]");
684 return;
685 }
686
687 skb = skb_recv_datagram(sk, 0, 1, &ret);
688 if (!skb) {
689 rxrpc_put_local(local);
690 if (ret == -EAGAIN)
691 return;
692 _debug("UDP socket error %d", ret);
693 return;
694 }
695
696 rxrpc_new_skb(skb);
697
698 _net("recv skb %p", skb);
699
700 /* we'll probably need to checksum it (didn't call sock_recvmsg) */
701 if (skb_checksum_complete(skb)) {
702 rxrpc_free_skb(skb);
703 rxrpc_put_local(local);
704 _leave(" [CSUM failed]");
705 return;
706 }
707
708 /* the socket buffer we have is owned by UDP, with UDP's data all over
709 * it, but we really want our own */
710 skb_orphan(skb);
711 sp = rxrpc_skb(skb);
712 memset(sp, 0, sizeof(*sp));
713
714 _net("Rx UDP packet from %08x:%04hu",
715 ntohl(ip_hdr(skb)->saddr), ntohs(udp_hdr(skb)->source));
716
717 /* dig out the RxRPC connection details */
718 if (skb_copy_bits(skb, sizeof(struct udphdr), &sp->hdr,
719 sizeof(sp->hdr)) < 0)
720 goto bad_message;
721 if (!pskb_pull(skb, sizeof(struct udphdr) + sizeof(sp->hdr)))
722 BUG();
723
724 _net("Rx RxRPC %s ep=%x call=%x:%x",
725 sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient",
726 ntohl(sp->hdr.epoch),
727 ntohl(sp->hdr.cid),
728 ntohl(sp->hdr.callNumber));
729
730 if (sp->hdr.type == 0 || sp->hdr.type >= RXRPC_N_PACKET_TYPES) {
731 _proto("Rx Bad Packet Type %u", sp->hdr.type);
732 goto bad_message;
733 }
734
735 if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
736 (sp->hdr.callNumber == 0 || sp->hdr.seq == 0))
737 goto bad_message;
738
739 peer = rxrpc_find_peer(local, ip_hdr(skb)->saddr, udp_hdr(skb)->source);
740 if (IS_ERR(peer))
741 goto cant_route_call;
742
743 trans = rxrpc_find_transport(local, peer);
744 rxrpc_put_peer(peer);
745 if (!trans)
746 goto cant_route_call;
747
748 conn = rxrpc_find_connection(trans, &sp->hdr);
749 rxrpc_put_transport(trans);
750 if (!conn)
751 goto cant_route_call;
752
753 _debug("CONN %p {%d}", conn, conn->debug_id);
754
755 if (sp->hdr.callNumber == 0)
756 rxrpc_post_packet_to_conn(conn, skb);
757 else
758 rxrpc_post_packet_to_call(conn, skb);
759 rxrpc_put_connection(conn);
760 rxrpc_put_local(local);
761 return;
762
763cant_route_call:
764 _debug("can't route call");
765 if (sp->hdr.flags & RXRPC_CLIENT_INITIATED &&
766 sp->hdr.type == RXRPC_PACKET_TYPE_DATA) {
767 if (sp->hdr.seq == __constant_cpu_to_be32(1)) {
768 _debug("first packet");
769 skb_queue_tail(&local->accept_queue, skb);
770 schedule_work(&local->acceptor);
771 rxrpc_put_local(local);
772 _leave(" [incoming]");
773 return;
774 }
775 skb->priority = RX_INVALID_OPERATION;
776 } else {
777 skb->priority = RX_CALL_DEAD;
778 }
779
780 _debug("reject");
781 rxrpc_reject_packet(local, skb);
782 rxrpc_put_local(local);
783 _leave(" [no call]");
784 return;
785
786bad_message:
787 skb->priority = RX_PROTOCOL_ERROR;
788 rxrpc_reject_packet(local, skb);
789 rxrpc_put_local(local);
790 _leave(" [badmsg]");
791}
generated by cgit v1.2.2 (git 2.25.0) at 2026-01-07 19:08:06 -0500