summaryrefslogtreecommitdiffstats
path: root/net/rxrpc/ar-internal.h
blob: 66c91707788000ba08d1d472ca8aab2493d2b46b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
/* AF_RXRPC internal definitions
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/atomic.h>
#include <linux/seqlock.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <rxrpc/packet.h>

#if 0
#define CHECK_SLAB_OKAY(X)				     \
	BUG_ON(atomic_read((X)) >> (sizeof(atomic_t) - 2) == \
	       (POISON_FREE << 8 | POISON_FREE))
#else
#define CHECK_SLAB_OKAY(X) do {} while (0)
#endif

#define FCRYPT_BSIZE 8
struct rxrpc_crypt {
	union {
		u8	x[FCRYPT_BSIZE];
		__be32	n[2];
	};
} __attribute__((aligned(8)));

#define rxrpc_queue_work(WS)	queue_work(rxrpc_workqueue, (WS))
#define rxrpc_queue_delayed_work(WS,D)	\
	queue_delayed_work(rxrpc_workqueue, (WS), (D))

#define rxrpc_queue_call(CALL)	rxrpc_queue_work(&(CALL)->processor)

struct rxrpc_connection;

/*
 * sk_state for RxRPC sockets
 */
enum {
	RXRPC_UNBOUND = 0,
	RXRPC_CLIENT_UNBOUND,		/* Unbound socket used as client */
	RXRPC_CLIENT_BOUND,		/* client local address bound */
	RXRPC_SERVER_BOUND,		/* server local address bound */
	RXRPC_SERVER_LISTENING,		/* server listening for connections */
	RXRPC_CLOSE,			/* socket is being closed */
};

/*
 * RxRPC socket definition
 */
struct rxrpc_sock {
	/* WARNING: sk has to be the first member */
	struct sock		sk;
	rxrpc_interceptor_t	interceptor;	/* kernel service Rx interceptor function */
	struct rxrpc_local	*local;		/* local endpoint */
	struct list_head	listen_link;	/* link in the local endpoint's listen list */
	struct list_head	secureq;	/* calls awaiting connection security clearance */
	struct list_head	acceptq;	/* calls awaiting acceptance */
	struct key		*key;		/* security for this socket */
	struct key		*securities;	/* list of server security descriptors */
	struct rb_root		calls;		/* outstanding calls on this socket */
	unsigned long		flags;
#define RXRPC_SOCK_CONNECTED		0	/* connect_srx is set */
	rwlock_t		call_lock;	/* lock for calls */
	u32			min_sec_level;	/* minimum security level */
#define RXRPC_SECURITY_MAX	RXRPC_SECURITY_ENCRYPT
	bool			exclusive;	/* Exclusive connection for a client socket */
	sa_family_t		family;		/* Protocol family created with */
	struct sockaddr_rxrpc	srx;		/* local address */
	struct sockaddr_rxrpc	connect_srx;	/* Default client address from connect() */
};

#define rxrpc_sk(__sk) container_of((__sk), struct rxrpc_sock, sk)

/*
 * CPU-byteorder normalised Rx packet header.
 */
struct rxrpc_host_header {
	u32		epoch;		/* client boot timestamp */
	u32		cid;		/* connection and channel ID */
	u32		callNumber;	/* call ID (0 for connection-level packets) */
	u32		seq;		/* sequence number of pkt in call stream */
	u32		serial;		/* serial number of pkt sent to network */
	u8		type;		/* packet type */
	u8		flags;		/* packet flags */
	u8		userStatus;	/* app-layer defined status */
	u8		securityIndex;	/* security protocol ID */
	union {
		u16	_rsvd;		/* reserved */
		u16	cksum;		/* kerberos security checksum */
	};
	u16		serviceId;	/* service ID */
} __packed;

/*
 * RxRPC socket buffer private variables
 * - max 48 bytes (struct sk_buff::cb)
 */
struct rxrpc_skb_priv {
	struct rxrpc_call	*call;		/* call with which associated */
	unsigned long		resend_at;	/* time in jiffies at which to resend */
	union {
		unsigned int	offset;		/* offset into buffer of next read */
		int		remain;		/* amount of space remaining for next write */
		u32		error;		/* network error code */
		bool		need_resend;	/* T if needs resending */
	};

	struct rxrpc_host_header hdr;		/* RxRPC packet header from this packet */
};

#define rxrpc_skb(__skb) ((struct rxrpc_skb_priv *) &(__skb)->cb)

enum rxrpc_command {
	RXRPC_CMD_SEND_DATA,		/* send data message */
	RXRPC_CMD_SEND_ABORT,		/* request abort generation */
	RXRPC_CMD_ACCEPT,		/* [server] accept incoming call */
	RXRPC_CMD_REJECT_BUSY,		/* [server] reject a call as busy */
};

/*
 * RxRPC security module interface
 */
struct rxrpc_security {
	const char		*name;		/* name of this service */
	u8			security_index;	/* security type provided */

	/* Initialise a security service */
	int (*init)(void);

	/* Clean up a security service */
	void (*exit)(void);

	/* initialise a connection's security */
	int (*init_connection_security)(struct rxrpc_connection *);

	/* prime a connection's packet security */
	int (*prime_packet_security)(struct rxrpc_connection *);

	/* impose security on a packet */
	int (*secure_packet)(struct rxrpc_call *,
			     struct sk_buff *,
			     size_t,
			     void *);

	/* verify the security on a received packet */
	int (*verify_packet)(struct rxrpc_call *, struct sk_buff *, u32 *);

	/* issue a challenge */
	int (*issue_challenge)(struct rxrpc_connection *);

	/* respond to a challenge */
	int (*respond_to_challenge)(struct rxrpc_connection *,
				    struct sk_buff *,
				    u32 *);

	/* verify a response */
	int (*verify_response)(struct rxrpc_connection *,
			       struct sk_buff *,
			       u32 *);

	/* clear connection security */
	void (*clear)(struct rxrpc_connection *);
};

/*
 * RxRPC local transport endpoint description
 * - owned by a single AF_RXRPC socket
 * - pointed to by transport socket struct sk_user_data
 */
struct rxrpc_local {
	struct rcu_head		rcu;
	atomic_t		usage;
	struct list_head	link;
	struct socket		*socket;	/* my UDP socket */
	struct work_struct	processor;
	struct list_head	services;	/* services listening on this endpoint */
	struct rw_semaphore	defrag_sem;	/* control re-enablement of IP DF bit */
	struct sk_buff_head	accept_queue;	/* incoming calls awaiting acceptance */
	struct sk_buff_head	reject_queue;	/* packets awaiting rejection */
	struct sk_buff_head	event_queue;	/* endpoint event packets awaiting processing */
	struct rb_root		client_conns;	/* Client connections by socket params */
	spinlock_t		client_conns_lock; /* Lock for client_conns */
	spinlock_t		lock;		/* access lock */
	rwlock_t		services_lock;	/* lock for services list */
	int			debug_id;	/* debug ID for printks */
	bool			dead;
	struct sockaddr_rxrpc	srx;		/* local address */
};

/*
 * RxRPC remote transport endpoint definition
 * - matched by local endpoint, remote port, address and protocol type
 */
struct rxrpc_peer {
	struct rcu_head		rcu;		/* This must be first */
	atomic_t		usage;
	unsigned long		hash_key;
	struct hlist_node	hash_link;
	struct rxrpc_local	*local;
	struct hlist_head	error_targets;	/* targets for net error distribution */
	struct work_struct	error_distributor;
	struct rb_root		service_conns;	/* Service connections */
	seqlock_t		service_conn_lock;
	spinlock_t		lock;		/* access lock */
	unsigned int		if_mtu;		/* interface MTU for this peer */
	unsigned int		mtu;		/* network MTU for this peer */
	unsigned int		maxdata;	/* data size (MTU - hdrsize) */
	unsigned short		hdrsize;	/* header size (IP + UDP + RxRPC) */
	int			debug_id;	/* debug ID for printks */
	int			error_report;	/* Net (+0) or local (+1000000) to distribute */
#define RXRPC_LOCAL_ERROR_OFFSET 1000000
	struct sockaddr_rxrpc	srx;		/* remote address */

	/* calculated RTT cache */
#define RXRPC_RTT_CACHE_SIZE 32
	suseconds_t		rtt;		/* current RTT estimate (in uS) */
	unsigned int		rtt_point;	/* next entry at which to insert */
	unsigned int		rtt_usage;	/* amount of cache actually used */
	suseconds_t		rtt_cache[RXRPC_RTT_CACHE_SIZE]; /* calculated RTT cache */
};

/*
 * Keys for matching a connection.
 */
struct rxrpc_conn_proto {
	union {
		struct {
			u32	epoch;		/* epoch of this connection */
			u32	cid;		/* connection ID */
		};
		u64		index_key;
	};
};

struct rxrpc_conn_parameters {
	struct rxrpc_local	*local;		/* Representation of local endpoint */
	struct rxrpc_peer	*peer;		/* Remote endpoint */
	struct key		*key;		/* Security details */
	bool			exclusive;	/* T if conn is exclusive */
	u16			service_id;	/* Service ID for this connection */
	u32			security_level;	/* Security level selected */
};

/*
 * Bits in the connection flags.
 */
enum rxrpc_conn_flag {
	RXRPC_CONN_HAS_IDR,		/* Has a client conn ID assigned */
	RXRPC_CONN_IN_SERVICE_CONNS,	/* Conn is in peer->service_conns */
	RXRPC_CONN_IN_CLIENT_CONNS,	/* Conn is in local->client_conns */
};

/*
 * Events that can be raised upon a connection.
 */
enum rxrpc_conn_event {
	RXRPC_CONN_EV_CHALLENGE,	/* Send challenge packet */
};

/*
 * The connection protocol state.
 */
enum rxrpc_conn_proto_state {
	RXRPC_CONN_UNUSED,		/* Connection not yet attempted */
	RXRPC_CONN_CLIENT,		/* Client connection */
	RXRPC_CONN_SERVICE_UNSECURED,	/* Service unsecured connection */
	RXRPC_CONN_SERVICE_CHALLENGING,	/* Service challenging for security */
	RXRPC_CONN_SERVICE,		/* Service secured connection */
	RXRPC_CONN_REMOTELY_ABORTED,	/* Conn aborted by peer */
	RXRPC_CONN_LOCALLY_ABORTED,	/* Conn aborted locally */
	RXRPC_CONN_NETWORK_ERROR,	/* Conn terminated by network error */
	RXRPC_CONN__NR_STATES
};

/*
 * RxRPC connection definition
 * - matched by { local, peer, epoch, conn_id, direction }
 * - each connection can only handle four simultaneous calls
 */
struct rxrpc_connection {
	struct rxrpc_conn_proto	proto;
	struct rxrpc_conn_parameters params;

	spinlock_t		channel_lock;

	struct rxrpc_channel {
		struct rxrpc_call __rcu	*call;		/* Active call */
		u32			call_id;	/* ID of current call */
		u32			call_counter;	/* Call ID counter */
		u32			last_call;	/* ID of last call */
		u32			last_result;	/* Result of last call (0/abort) */
	} channels[RXRPC_MAXCALLS];
	wait_queue_head_t	channel_wq;	/* queue to wait for channel to become available */

	struct rcu_head		rcu;
	struct work_struct	processor;	/* connection event processor */
	union {
		struct rb_node	client_node;	/* Node in local->client_conns */
		struct rb_node	service_node;	/* Node in peer->service_conns */
	};
	struct list_head	link;		/* link in master connection list */
	struct sk_buff_head	rx_queue;	/* received conn-level packets */
	const struct rxrpc_security *security;	/* applied security module */
	struct key		*server_key;	/* security for this service */
	struct crypto_skcipher	*cipher;	/* encryption handle */
	struct rxrpc_crypt	csum_iv;	/* packet checksum base */
	unsigned long		flags;
	unsigned long		events;
	unsigned long		idle_timestamp;	/* Time at which last became idle */
	spinlock_t		state_lock;	/* state-change lock */
	atomic_t		usage;
	enum rxrpc_conn_proto_state state : 8;	/* current state of connection */
	u32			local_abort;	/* local abort code */
	u32			remote_abort;	/* remote abort code */
	int			error;		/* local error incurred */
	int			debug_id;	/* debug ID for printks */
	atomic_t		serial;		/* packet serial number counter */
	atomic_t		hi_serial;	/* highest serial number received */
	atomic_t		avail_chans;	/* number of channels available */
	u8			size_align;	/* data size alignment (for security) */
	u8			header_size;	/* rxrpc + security header size */
	u8			security_size;	/* security header size */
	u32			security_nonce;	/* response re-use preventer */
	u8			security_ix;	/* security type */
	u8			out_clientflag;	/* RXRPC_CLIENT_INITIATED if we are client */
};

/*
 * Flags in call->flags.
 */
enum rxrpc_call_flag {
	RXRPC_CALL_RELEASED,		/* call has been released - no more message to userspace */
	RXRPC_CALL_TERMINAL_MSG,	/* call has given the socket its final message */
	RXRPC_CALL_RCVD_LAST,		/* all packets received */
	RXRPC_CALL_RUN_RTIMER,		/* Tx resend timer started */
	RXRPC_CALL_TX_SOFT_ACK,		/* sent some soft ACKs */
	RXRPC_CALL_INIT_ACCEPT,		/* acceptance was initiated */
	RXRPC_CALL_HAS_USERID,		/* has a user ID attached */
	RXRPC_CALL_EXPECT_OOS,		/* expect out of sequence packets */
	RXRPC_CALL_IS_SERVICE,		/* Call is service call */
};

/*
 * Events that can be raised on a call.
 */
enum rxrpc_call_event {
	RXRPC_CALL_EV_RCVD_ACKALL,	/* ACKALL or reply received */
	RXRPC_CALL_EV_RCVD_BUSY,	/* busy packet received */
	RXRPC_CALL_EV_RCVD_ABORT,	/* abort packet received */
	RXRPC_CALL_EV_RCVD_ERROR,	/* network error received */
	RXRPC_CALL_EV_ACK_FINAL,	/* need to generate final ACK (and release call) */
	RXRPC_CALL_EV_ACK,		/* need to generate ACK */
	RXRPC_CALL_EV_REJECT_BUSY,	/* need to generate busy message */
	RXRPC_CALL_EV_ABORT,		/* need to generate abort */
	RXRPC_CALL_EV_CONN_ABORT,	/* local connection abort generated */
	RXRPC_CALL_EV_RESEND_TIMER,	/* Tx resend timer expired */
	RXRPC_CALL_EV_RESEND,		/* Tx resend required */
	RXRPC_CALL_EV_DRAIN_RX_OOS,	/* drain the Rx out of sequence queue */
	RXRPC_CALL_EV_LIFE_TIMER,	/* call's lifetimer ran out */
	RXRPC_CALL_EV_ACCEPTED,		/* incoming call accepted by userspace app */
	RXRPC_CALL_EV_SECURED,		/* incoming call's connection is now secure */
	RXRPC_CALL_EV_POST_ACCEPT,	/* need to post an "accept?" message to the app */
	RXRPC_CALL_EV_RELEASE,		/* need to release the call's resources */
};

/*
 * The states that a call can be in.
 */
enum rxrpc_call_state {
	RXRPC_CALL_UNINITIALISED,
	RXRPC_CALL_CLIENT_AWAIT_CONN,	/* - client waiting for connection to become available */
	RXRPC_CALL_CLIENT_SEND_REQUEST,	/* - client sending request phase */
	RXRPC_CALL_CLIENT_AWAIT_REPLY,	/* - client awaiting reply */
	RXRPC_CALL_CLIENT_RECV_REPLY,	/* - client receiving reply phase */
	RXRPC_CALL_CLIENT_FINAL_ACK,	/* - client sending final ACK phase */
	RXRPC_CALL_SERVER_SECURING,	/* - server securing request connection */
	RXRPC_CALL_SERVER_ACCEPTING,	/* - server accepting request */
	RXRPC_CALL_SERVER_RECV_REQUEST,	/* - server receiving request */
	RXRPC_CALL_SERVER_ACK_REQUEST,	/* - server pending ACK of request */
	RXRPC_CALL_SERVER_SEND_REPLY,	/* - server sending reply */
	RXRPC_CALL_SERVER_AWAIT_ACK,	/* - server awaiting final ACK */
	RXRPC_CALL_COMPLETE,		/* - call completed */
	RXRPC_CALL_SERVER_BUSY,		/* - call rejected by busy server */
	RXRPC_CALL_REMOTELY_ABORTED,	/* - call aborted by peer */
	RXRPC_CALL_LOCALLY_ABORTED,	/* - call aborted locally on error or close */
	RXRPC_CALL_NETWORK_ERROR,	/* - call terminated by network error */
	RXRPC_CALL_DEAD,		/* - call is dead */
	NR__RXRPC_CALL_STATES
};

/*
 * RxRPC call definition
 * - matched by { connection, call_id }
 */
struct rxrpc_call {
	struct rcu_head		rcu;
	struct rxrpc_connection	*conn;		/* connection carrying call */
	struct rxrpc_sock	*socket;	/* socket responsible */
	struct timer_list	lifetimer;	/* lifetime remaining on call */
	struct timer_list	deadspan;	/* reap timer for re-ACK'ing, etc  */
	struct timer_list	ack_timer;	/* ACK generation timer */
	struct timer_list	resend_timer;	/* Tx resend timer */
	struct work_struct	destroyer;	/* call destroyer */
	struct work_struct	processor;	/* packet processor and ACK generator */
	struct list_head	link;		/* link in master call list */
	struct hlist_node	error_link;	/* link in error distribution list */
	struct list_head	accept_link;	/* calls awaiting acceptance */
	struct rb_node		sock_node;	/* node in socket call tree */
	struct sk_buff_head	rx_queue;	/* received packets */
	struct sk_buff_head	rx_oos_queue;	/* packets received out of sequence */
	struct sk_buff		*tx_pending;	/* Tx socket buffer being filled */
	wait_queue_head_t	tx_waitq;	/* wait for Tx window space to become available */
	__be32			crypto_buf[2];	/* Temporary packet crypto buffer */
	unsigned long		user_call_ID;	/* user-defined call ID */
	unsigned long		creation_jif;	/* time of call creation */
	unsigned long		flags;
	unsigned long		events;
	spinlock_t		lock;
	rwlock_t		state_lock;	/* lock for state transition */
	atomic_t		usage;
	atomic_t		skb_count;	/* Outstanding packets on this call */
	atomic_t		sequence;	/* Tx data packet sequence counter */
	u32			local_abort;	/* local abort code */
	u32			remote_abort;	/* remote abort code */
	int			error_report;	/* Network error (ICMP/local transport) */
	int			error;		/* Local error incurred */
	enum rxrpc_call_state	state : 8;	/* current state of call */
	u16			service_id;	/* service ID */
	u32			call_id;	/* call ID on connection  */
	u32			cid;		/* connection ID plus channel index */
	int			debug_id;	/* debug ID for printks */

	/* transmission-phase ACK management */
	u8			acks_head;	/* offset into window of first entry */
	u8			acks_tail;	/* offset into window of last entry */
	u8			acks_winsz;	/* size of un-ACK'd window */
	u8			acks_unacked;	/* lowest unacked packet in last ACK received */
	int			acks_latest;	/* serial number of latest ACK received */
	rxrpc_seq_t		acks_hard;	/* highest definitively ACK'd msg seq */
	unsigned long		*acks_window;	/* sent packet window
						 * - elements are pointers with LSB set if ACK'd
						 */

	/* receive-phase ACK management */
	rxrpc_seq_t		rx_data_expect;	/* next data seq ID expected to be received */
	rxrpc_seq_t		rx_data_post;	/* next data seq ID expected to be posted */
	rxrpc_seq_t		rx_data_recv;	/* last data seq ID encountered by recvmsg */
	rxrpc_seq_t		rx_data_eaten;	/* last data seq ID consumed by recvmsg */
	rxrpc_seq_t		rx_first_oos;	/* first packet in rx_oos_queue (or 0) */
	rxrpc_seq_t		ackr_win_top;	/* top of ACK window (rx_data_eaten is bottom) */
	rxrpc_seq_t		ackr_prev_seq;	/* previous sequence number received */
	u8			ackr_reason;	/* reason to ACK */
	rxrpc_serial_t		ackr_serial;	/* serial of packet being ACK'd */
	atomic_t		ackr_not_idle;	/* number of packets in Rx queue */

	/* received packet records, 1 bit per record */
#define RXRPC_ACKR_WINDOW_ASZ DIV_ROUND_UP(RXRPC_MAXACKS, BITS_PER_LONG)
	unsigned long		ackr_window[RXRPC_ACKR_WINDOW_ASZ + 1];
};

/*
 * locally abort an RxRPC call
 */
static inline void rxrpc_abort_call(struct rxrpc_call *call, u32 abort_code)
{
	write_lock_bh(&call->state_lock);
	if (call->state < RXRPC_CALL_COMPLETE) {
		call->local_abort = abort_code;
		call->state = RXRPC_CALL_LOCALLY_ABORTED;
		set_bit(RXRPC_CALL_EV_ABORT, &call->events);
	}
	write_unlock_bh(&call->state_lock);
}

#include <trace/events/rxrpc.h>

/*
 * af_rxrpc.c
 */
extern atomic_t rxrpc_n_skbs;
extern u32 rxrpc_epoch;
extern atomic_t rxrpc_debug_id;
extern struct workqueue_struct *rxrpc_workqueue;

/*
 * call_accept.c
 */
void rxrpc_accept_incoming_calls(struct rxrpc_local *);
struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *, unsigned long);
int rxrpc_reject_call(struct rxrpc_sock *);

/*
 * call_event.c
 */
void __rxrpc_propose_ACK(struct rxrpc_call *, u8, u32, bool);
void rxrpc_propose_ACK(struct rxrpc_call *, u8, u32, bool);
void rxrpc_process_call(struct work_struct *);

/*
 * call_object.c
 */
extern unsigned int rxrpc_max_call_lifetime;
extern unsigned int rxrpc_dead_call_expiry;
extern struct kmem_cache *rxrpc_call_jar;
extern struct list_head rxrpc_calls;
extern rwlock_t rxrpc_call_lock;

struct rxrpc_call *rxrpc_find_call_by_user_ID(struct rxrpc_sock *, unsigned long);
struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *,
					 struct rxrpc_conn_parameters *,
					 struct sockaddr_rxrpc *,
					 unsigned long, gfp_t);
struct rxrpc_call *rxrpc_incoming_call(struct rxrpc_sock *,
				       struct rxrpc_connection *,
				       struct sk_buff *);
void rxrpc_release_call(struct rxrpc_call *);
void rxrpc_release_calls_on_socket(struct rxrpc_sock *);
void __rxrpc_put_call(struct rxrpc_call *);
void __exit rxrpc_destroy_all_calls(void);

static inline bool rxrpc_is_service_call(const struct rxrpc_call *call)
{
	return test_bit(RXRPC_CALL_IS_SERVICE, &call->flags);
}

static inline bool rxrpc_is_client_call(const struct rxrpc_call *call)
{
	return !rxrpc_is_service_call(call);
}

/*
 * conn_client.c
 */
extern struct idr rxrpc_client_conn_ids;

void rxrpc_destroy_client_conn_ids(void);
int rxrpc_connect_call(struct rxrpc_call *, struct rxrpc_conn_parameters *,
		       struct sockaddr_rxrpc *, gfp_t);
void rxrpc_unpublish_client_conn(struct rxrpc_connection *);

/*
 * conn_event.c
 */
void rxrpc_process_connection(struct work_struct *);
void rxrpc_reject_packet(struct rxrpc_local *, struct sk_buff *);
void rxrpc_reject_packets(struct rxrpc_local *);

/*
 * conn_object.c
 */
extern unsigned int rxrpc_connection_expiry;
extern struct list_head rxrpc_connections;
extern rwlock_t rxrpc_connection_lock;

int rxrpc_extract_addr_from_skb(struct sockaddr_rxrpc *, struct sk_buff *);
struct rxrpc_connection *rxrpc_alloc_connection(gfp_t);
struct rxrpc_connection *rxrpc_find_connection_rcu(struct rxrpc_local *,
						   struct sk_buff *);
void __rxrpc_disconnect_call(struct rxrpc_call *);
void rxrpc_disconnect_call(struct rxrpc_call *);
void __rxrpc_put_connection(struct rxrpc_connection *);
void __exit rxrpc_destroy_all_connections(void);

static inline bool rxrpc_conn_is_client(const struct rxrpc_connection *conn)
{
	return conn->out_clientflag;
}

static inline bool rxrpc_conn_is_service(const struct rxrpc_connection *conn)
{
	return !rxrpc_conn_is_client(conn);
}

static inline void rxrpc_get_connection(struct rxrpc_connection *conn)
{
	atomic_inc(&conn->usage);
}

static inline
struct rxrpc_connection *rxrpc_get_connection_maybe(struct rxrpc_connection *conn)
{
	return atomic_inc_not_zero(&conn->usage) ? conn : NULL;
}

static inline void rxrpc_put_connection(struct rxrpc_connection *conn)
{
	if (conn && atomic_dec_return(&conn->usage) == 1)
		__rxrpc_put_connection(conn);
}


static inline bool rxrpc_queue_conn(struct rxrpc_connection *conn)
{
	if (!rxrpc_get_connection_maybe(conn))
		return false;
	if (!rxrpc_queue_work(&conn->processor))
		rxrpc_put_connection(conn);
	return true;
}

/*
 * conn_service.c
 */
struct rxrpc_connection *rxrpc_find_service_conn_rcu(struct rxrpc_peer *,
						     struct sk_buff *);
struct rxrpc_connection *rxrpc_incoming_connection(struct rxrpc_local *,
						   struct sockaddr_rxrpc *,
						   struct sk_buff *);
void rxrpc_unpublish_service_conn(struct rxrpc_connection *);

/*
 * input.c
 */
void rxrpc_data_ready(struct sock *);
int rxrpc_queue_rcv_skb(struct rxrpc_call *, struct sk_buff *, bool, bool);
void rxrpc_fast_process_packet(struct rxrpc_call *, struct sk_buff *);

/*
 * insecure.c
 */
extern const struct rxrpc_security rxrpc_no_security;

/*
 * key.c
 */
extern struct key_type key_type_rxrpc;
extern struct key_type key_type_rxrpc_s;

int rxrpc_request_key(struct rxrpc_sock *, char __user *, int);
int rxrpc_server_keyring(struct rxrpc_sock *, char __user *, int);
int rxrpc_get_server_data_key(struct rxrpc_connection *, const void *, time_t,
			      u32);

/*
 * local_event.c
 */
extern void rxrpc_process_local_events(struct rxrpc_local *);

/*
 * local_object.c
 */
struct rxrpc_local *rxrpc_lookup_local(const struct sockaddr_rxrpc *);
void __rxrpc_put_local(struct rxrpc_local *);
void __exit rxrpc_destroy_all_locals(void);

static inline void rxrpc_get_local(struct rxrpc_local *local)
{
	atomic_inc(&local->usage);
}

static inline
struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local)
{
	return atomic_inc_not_zero(&local->usage) ? local : NULL;
}

static inline void rxrpc_put_local(struct rxrpc_local *local)
{
	if (local && atomic_dec_and_test(&local->usage))
		__rxrpc_put_local(local);
}

static inline void rxrpc_queue_local(struct rxrpc_local *local)
{
	rxrpc_queue_work(&local->processor);
}

/*
 * misc.c
 */
extern unsigned int rxrpc_max_backlog __read_mostly;
extern unsigned int rxrpc_requested_ack_delay;
extern unsigned int rxrpc_soft_ack_delay;
extern unsigned int rxrpc_idle_ack_delay;
extern unsigned int rxrpc_rx_window_size;
extern unsigned int rxrpc_rx_mtu;
extern unsigned int rxrpc_rx_jumbo_max;

extern const char *const rxrpc_pkts[];
extern const s8 rxrpc_ack_priority[];

extern const char *rxrpc_acks(u8 reason);

/*
 * output.c
 */
extern unsigned int rxrpc_resend_timeout;

int rxrpc_send_data_packet(struct rxrpc_connection *, struct sk_buff *);
int rxrpc_do_sendmsg(struct rxrpc_sock *, struct msghdr *, size_t);

/*
 * peer_event.c
 */
void rxrpc_error_report(struct sock *);
void rxrpc_peer_error_distributor(struct work_struct *);

/*
 * peer_object.c
 */
struct rxrpc_peer *rxrpc_lookup_peer_rcu(struct rxrpc_local *,
					 const struct sockaddr_rxrpc *);
struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *,
				     struct sockaddr_rxrpc *, gfp_t);
struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *, gfp_t);

static inline void rxrpc_get_peer(struct rxrpc_peer *peer)
{
	atomic_inc(&peer->usage);
}

static inline
struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer)
{
	return atomic_inc_not_zero(&peer->usage) ? peer : NULL;
}

extern void __rxrpc_put_peer(struct rxrpc_peer *peer);
static inline void rxrpc_put_peer(struct rxrpc_peer *peer)
{
	if (peer && atomic_dec_and_test(&peer->usage))
		__rxrpc_put_peer(peer);
}

/*
 * proc.c
 */
extern const char *const rxrpc_call_states[];
extern const struct file_operations rxrpc_call_seq_fops;
extern const struct file_operations rxrpc_connection_seq_fops;

/*
 * recvmsg.c
 */
void rxrpc_remove_user_ID(struct rxrpc_sock *, struct rxrpc_call *);
int rxrpc_recvmsg(struct socket *, struct msghdr *, size_t, int);

/*
 * rxkad.c
 */
#ifdef CONFIG_RXKAD
extern const struct rxrpc_security rxkad;
#endif

/*
 * security.c
 */
int __init rxrpc_init_security(void);
void rxrpc_exit_security(void);
int rxrpc_init_client_conn_security(struct rxrpc_connection *);
int rxrpc_init_server_conn_security(struct rxrpc_connection *);

/*
 * skbuff.c
 */
void rxrpc_packet_destructor(struct sk_buff *);
void rxrpc_new_skb(struct sk_buff *);
void rxrpc_see_skb(struct sk_buff *);
void rxrpc_get_skb(struct sk_buff *);
void rxrpc_free_skb(struct sk_buff *);
void rxrpc_purge_queue(struct sk_buff_head *);

/*
 * sysctl.c
 */
#ifdef CONFIG_SYSCTL
extern int __init rxrpc_sysctl_init(void);
extern void rxrpc_sysctl_exit(void);
#else
static inline int __init rxrpc_sysctl_init(void) { return 0; }
static inline void rxrpc_sysctl_exit(void) {}
#endif

/*
 * utils.c
 */
int rxrpc_extract_addr_from_skb(struct sockaddr_rxrpc *, struct sk_buff *);

/*
 * debug tracing
 */
extern unsigned int rxrpc_debug;

#define dbgprintk(FMT,...) \
	printk("[%-6.6s] "FMT"\n", current->comm ,##__VA_ARGS__)

#define kenter(FMT,...)	dbgprintk("==> %s("FMT")",__func__ ,##__VA_ARGS__)
#define kleave(FMT,...)	dbgprintk("<== %s()"FMT"",__func__ ,##__VA_ARGS__)
#define kdebug(FMT,...)	dbgprintk("    "FMT ,##__VA_ARGS__)
#define kproto(FMT,...)	dbgprintk("### "FMT ,##__VA_ARGS__)
#define knet(FMT,...)	dbgprintk("@@@ "FMT ,##__VA_ARGS__)


#if defined(__KDEBUG)
#define _enter(FMT,...)	kenter(FMT,##__VA_ARGS__)
#define _leave(FMT,...)	kleave(FMT,##__VA_ARGS__)
#define _debug(FMT,...)	kdebug(FMT,##__VA_ARGS__)
#define _proto(FMT,...)	kproto(FMT,##__VA_ARGS__)
#define _net(FMT,...)	knet(FMT,##__VA_ARGS__)

#elif defined(CONFIG_AF_RXRPC_DEBUG)
#define RXRPC_DEBUG_KENTER	0x01
#define RXRPC_DEBUG_KLEAVE	0x02
#define RXRPC_DEBUG_KDEBUG	0x04
#define RXRPC_DEBUG_KPROTO	0x08
#define RXRPC_DEBUG_KNET	0x10

#define _enter(FMT,...)					\
do {							\
	if (unlikely(rxrpc_debug & RXRPC_DEBUG_KENTER))	\
		kenter(FMT,##__VA_ARGS__);		\
} while (0)

#define _leave(FMT,...)					\
do {							\
	if (unlikely(rxrpc_debug & RXRPC_DEBUG_KLEAVE))	\
		kleave(FMT,##__VA_ARGS__);		\
} while (0)

#define _debug(FMT,...)					\
do {							\
	if (unlikely(rxrpc_debug & RXRPC_DEBUG_KDEBUG))	\
		kdebug(FMT,##__VA_ARGS__);		\
} while (0)

#define _proto(FMT,...)					\
do {							\
	if (unlikely(rxrpc_debug & RXRPC_DEBUG_KPROTO))	\
		kproto(FMT,##__VA_ARGS__);		\
} while (0)

#define _net(FMT,...)					\
do {							\
	if (unlikely(rxrpc_debug & RXRPC_DEBUG_KNET))	\
		knet(FMT,##__VA_ARGS__);		\
} while (0)

#else
#define _enter(FMT,...)	no_printk("==> %s("FMT")",__func__ ,##__VA_ARGS__)
#define _leave(FMT,...)	no_printk("<== %s()"FMT"",__func__ ,##__VA_ARGS__)
#define _debug(FMT,...)	no_printk("    "FMT ,##__VA_ARGS__)
#define _proto(FMT,...)	no_printk("### "FMT ,##__VA_ARGS__)
#define _net(FMT,...)	no_printk("@@@ "FMT ,##__VA_ARGS__)
#endif

/*
 * debug assertion checking
 */
#if 1 // defined(__KDEBUGALL)

#define ASSERT(X)						\
do {								\
	if (unlikely(!(X))) {					\
		pr_err("Assertion failed\n");			\
		BUG();						\
	}							\
} while (0)

#define ASSERTCMP(X, OP, Y)						\
do {									\
	unsigned long _x = (unsigned long)(X);				\
	unsigned long _y = (unsigned long)(Y);				\
	if (unlikely(!(_x OP _y))) {					\
		pr_err("Assertion failed - %lu(0x%lx) %s %lu(0x%lx) is false\n",			\
		       _x, _x, #OP, _y, _y);				\
		BUG();							\
	}								\
} while (0)

#define ASSERTIF(C, X)						\
do {								\
	if (unlikely((C) && !(X))) {				\
		pr_err("Assertion failed\n");			\
		BUG();						\
	}							\
} while (0)

#define ASSERTIFCMP(C, X, OP, Y)					\
do {									\
	unsigned long _x = (unsigned long)(X);				\
	unsigned long _y = (unsigned long)(Y);				\
	if (unlikely((C) && !(_x OP _y))) {				\
		pr_err("Assertion failed - %lu(0x%lx) %s %lu(0x%lx) is false\n", \
		       _x, _x, #OP, _y, _y);				\
		BUG();							\
	}								\
} while (0)

#else

#define ASSERT(X)				\
do {						\
} while (0)

#define ASSERTCMP(X, OP, Y)			\
do {						\
} while (0)

#define ASSERTIF(C, X)				\
do {						\
} while (0)

#define ASSERTIFCMP(C, X, OP, Y)		\
do {						\
} while (0)

#endif /* __KDEBUGALL */


#define rxrpc_get_call(CALL)				\
do {							\
	CHECK_SLAB_OKAY(&(CALL)->usage);		\
	if (atomic_inc_return(&(CALL)->usage) == 1)	\
		BUG();					\
} while (0)

#define rxrpc_put_call(CALL)				\
do {							\
	__rxrpc_put_call(CALL);				\
} while (0)