Loading...
  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
/*
 * Copyright (c) 2012-2020 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#ifndef _NETINET_MPTCP_VAR_H_
#define _NETINET_MPTCP_VAR_H_

#ifdef PRIVATE
#include <netinet/in.h>
#include <netinet/tcp.h>
#endif

#ifdef BSD_KERNEL_PRIVATE
#include <sys/queue.h>
#include <sys/protosw.h>
#include <kern/locks.h>
#include <mach/boolean.h>
#include <netinet/mp_pcb.h>
#include <netinet/tcp_var.h>
#include <os/log.h>

struct mpt_itf_info {
	uint32_t ifindex;
	uint32_t has_v4_conn:1,
	    has_v6_conn:1,
	    has_nat64_conn:1,
	    no_mptcp_support:1;
};

/*
 * MPTCP Session
 *
 * This is an extension to the multipath PCB specific for MPTCP, protected by
 * the per-PCB mpp_lock (also the socket's lock);
 */
struct mptses {
	struct mppcb    *mpte_mppcb;            /* back ptr to multipath PCB */
	struct mptcb    *mpte_mptcb;            /* ptr to MPTCP PCB */
	TAILQ_HEAD(, mptopt) mpte_sopts;        /* list of socket options */
	TAILQ_HEAD(, mptsub) mpte_subflows;     /* list of subflows */
#define MPTCP_MAX_NUM_SUBFLOWS 256
	uint16_t        mpte_numflows;          /* # of subflows in list */
	uint16_t        mpte_nummpcapflows;     /* # of MP_CAP subflows */
	sae_associd_t   mpte_associd;           /* MPTCP association ID */
	sae_connid_t    mpte_connid_last;       /* last used connection ID */

	uint64_t        mpte_time_target;
	thread_call_t   mpte_time_thread;
	thread_call_t   mpte_stop_urgency;

	uint32_t        mpte_last_cellicon_set;
	uint32_t        mpte_cellicon_increments;

	union {
		/* Source address of initial subflow */
		struct sockaddr _mpte_src;
		struct sockaddr_in _mpte_src_v4;
		struct sockaddr_in6 _mpte_src_v6;
	} mpte_u_src;
#define mpte_src mpte_u_src._mpte_src
#define __mpte_src_v4 mpte_u_src._mpte_src_v4
#define __mpte_src_v6 mpte_u_src._mpte_src_v6
	union {
		/* Destination address of initial subflow */
		struct sockaddr _mpte_dst;
		struct sockaddr_in _mpte_dst_v4;
		struct sockaddr_in6 _mpte_dst_v6;
	} mpte_u_dst;
#define mpte_dst mpte_u_dst._mpte_dst
#define __mpte_dst_v4 mpte_u_dst._mpte_dst_v4
#define __mpte_dst_v6 mpte_u_dst._mpte_dst_v6

	struct sockaddr_in      mpte_sub_dst_v4;
	struct sockaddr_in6     mpte_sub_dst_v6;
	uint8_t         sub_dst_addr_id_v4;
	uint8_t         sub_dst_addr_id_v6;

	uint16_t        mpte_alternate_port;    /* Alternate port for subflow establishment (network-byte-order) */

	int mpte_epid;
	uuid_t mpte_euuid;

	struct mptsub   *mpte_active_sub;       /* ptr to last active subf */
	uint16_t mpte_flags;                    /* per mptcp session flags */
#define MPTE_SND_REM_ADDR       0x01            /* Send Remove_addr option */
#define MPTE_SVCTYPE_CHECKED    0x02            /* Did entitlement-check for service-type */
#define MPTE_FIRSTPARTY         0x04            /* First-party app used multipath_extended entitlement */
#define MPTE_ACCESS_GRANTED     0x08            /* Access to cellular has been granted for this connection */
#define MPTE_FORCE_ENABLE       0x10            /* For MPTCP regardless of heuristics to detect middleboxes */
#define MPTE_IN_WORKLOOP        0x20            /* Are we currently inside the workloop ? */
#define MPTE_WORKLOOP_RELAUNCH  0x40            /* Another event got queued, we should restart the workloop */
#define MPTE_UNICAST_IP         0x80            /* New subflows are only being established towards the unicast IP in the ADD_ADDR */
#define MPTE_CELL_PROHIBITED    0x100           /* Cell access has been prohibited based on signal quality */
#define MPTE_FORCE_V0           0x200           /* Force MPTCP to use version 0 regradless of tcp cache */
#define MPTE_FORCE_V1           0x400           /* Force MPTCP to use version 1 regradless of tcp cache */
	uint8_t mpte_svctype;                   /* MPTCP Service type */
	uint8_t mpte_lost_aid;                  /* storing lost address id */
	uint8_t mpte_addrid_last;               /* storing address id parm */

#define MPTE_ITFINFO_SIZE       4
	uint32_t        mpte_itfinfo_size;
	struct mpt_itf_info     _mpte_itfinfo[MPTE_ITFINFO_SIZE];
	struct mpt_itf_info     *mpte_itfinfo;

	struct mbuf             *mpte_reinjectq;

	/* The below is used for stats */
	uint32_t        mpte_subflow_switches;  /* Number of subflow-switches in sending */
	uint32_t        mpte_used_cell:1,
	    mpte_used_wifi:1,
	    mpte_initial_cell:1,
	    mpte_triggered_cell,
	    mpte_handshake_success:1,
	    mpte_last_added_addr_is_v4:1;

	struct mptcp_itf_stats  mpte_itfstats[MPTCP_ITFSTATS_SIZE];
	uint64_t                mpte_init_txbytes __attribute__((aligned(8)));
	uint64_t                mpte_init_rxbytes __attribute__((aligned(8)));
};

static inline struct socket *
mptetoso(struct mptses *mpte)
{
	return mpte->mpte_mppcb->mpp_socket;
}

static inline struct mptses *
mptompte(struct mppcb *mp)
{
	return (struct mptses *)mp->mpp_pcbe;
}

static inline struct mptses *
mpsotompte(struct socket *so)
{
	return mptompte(mpsotomppcb(so));
}

static inline boolean_t
mpp_try_lock(struct mppcb *mp)
{
	if (!lck_mtx_try_lock(&mp->mpp_lock)) {
		return false;
	}

	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));

	return true;
}

static inline void
mpp_lock(struct mppcb *mp)
{
	lck_mtx_lock(&mp->mpp_lock);
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
}

static inline void
mpp_unlock(struct mppcb *mp)
{
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
	VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
	lck_mtx_unlock(&mp->mpp_lock);
}

static inline lck_mtx_t *
mpp_getlock(struct mppcb *mp, int flags)
{
	if (flags & PR_F_WILLUNLOCK) {
		VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
		VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
		VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
	}

	return &mp->mpp_lock;
}

static inline int
mptcp_subflow_cwnd_space(struct socket *so)
{
	struct tcpcb *tp = sototcpcb(so);
	int cwnd = (int)(MIN(tp->snd_wnd, tp->snd_cwnd) - (so->so_snd.sb_cc));

	return MIN(cwnd, sbspace(&so->so_snd));
}

static inline bool
mptcp_subflows_need_backup_flag(struct mptses *mpte)
{
	return mpte->mpte_svctype < MPTCP_SVCTYPE_AGGREGATE ||
	       mpte->mpte_svctype == MPTCP_SVCTYPE_PURE_HANDOVER;
}

/*
 * MPTCP socket options
 */
struct mptopt {
	TAILQ_ENTRY(mptopt)     mpo_entry;      /* glue to other options */
	uint32_t                mpo_flags;      /* see flags below */
	int                     mpo_level;      /* sopt_level */
	int                     mpo_name;       /* sopt_name */
	int                     mpo_intval;     /* sopt_val */
};

#define MPOF_ATTACHED           0x1     /* attached to MP socket */
#define MPOF_SUBFLOW_OK         0x2     /* can be issued on subflow socket */
#define MPOF_INTERIM            0x4     /* has not been issued on any subflow */

/*
 * MPTCP subflow
 *
 * Note that mpts_flags and mpts_evctl are modified via atomic operations.
 */
struct mptsub {
	TAILQ_ENTRY(mptsub)   mpts_entry;     /* glue to peer subflows */
	uint32_t              mpts_refcnt;    /* reference count */
	uint32_t              mpts_flags;     /* see flags below */
	uint32_t              mpts_evctl;     /* subflow control events */
	sae_connid_t          mpts_connid;    /* subflow connection ID */
	int                   mpts_oldintval; /* sopt_val before sosetopt  */
	struct mptses         *mpts_mpte;     /* back ptr to MPTCP session */
	struct socket         *mpts_socket;   /* subflow socket */
	struct sockaddr       *mpts_src;      /* source address */

	union {
		/* destination address */
		struct sockaddr         _mpts_dst;
		struct sockaddr_in      _mpts_dst_v4;
		struct sockaddr_in6     _mpts_dst_v6;
	} mpts_u_dst;
#define mpts_dst mpts_u_dst._mpts_dst
#define __mpts_dst_v4 mpts_u_dst._mpts_dst_v4
#define __mpts_dst_v6 mpts_u_dst._mpts_dst_v6
	u_int32_t               mpts_rel_seq;   /* running count of subflow # */
	u_int32_t               mpts_iss;       /* Initial sequence number, taking TFO into account */
	u_int32_t               mpts_ifscope;   /* scoped to the interface */
	uint32_t                mpts_probesoon; /* send probe after probeto */
	uint32_t                mpts_probecnt;  /* number of probes sent */
	uint32_t                mpts_maxseg;    /* cached value of t_maxseg */
};

/*
 * Valid values for mpts_flags.  In particular:
 *
 *    - MP_CAPABLE means that the connection is successfully established as
 *	MPTCP and data transfer may occur, but is not yet ready for multipath-
 *	related semantics until MP_READY.  I.e. if this is on the first subflow,
 *	it causes the MPTCP socket to transition to a connected state, except
 *	that additional subflows will not be established; they will be marked
 *	with PENDING and will be processed when the first subflow is marked
 *	with MP_READY.
 *
 *    - MP_READY implies that an MP_CAPABLE connection has been confirmed as
 *	an MPTCP connection.  See notes above.
 *
 *    - MP_DEGRADED implies that the connection has lost its MPTCP capabilities
 *	but data transfer on the MPTCP socket is unaffected.  Any existing
 *	PENDING subflows will be disconnected, and further attempts to connect
 *	additional subflows will be rejected.
 *
 * Note that these are per-subflow flags.  The setting and clearing of MP_READY
 * reflects the state of the MPTCP connection with regards to its multipath
 * semantics, via the MPTCPF_JOIN_READY flag.  Until that flag is set (meaning
 * until at least a subflow is marked with MP_READY), further connectx(2)
 * attempts to join will be queued.  When the flag is cleared (after it has
 * been set), further connectx(2) will fail (and existing queued ones will be
 * aborted) and the MPTCP connection loses all of its multipath semantics.
 *
 * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 */
#define MPTSF_ATTACHED          0x00000001      /* attached to MPTCP PCB */
#define MPTSF_CONNECTING        0x00000002      /* connection was attempted */
#define MPTSF_CONNECT_PENDING   0x00000004      /* will connect when MPTCP is ready */
#define MPTSF_CONNECTED         0x00000008      /* connection is established */
#define MPTSF_DISCONNECTING     0x00000010      /* disconnection was attempted */
#define MPTSF_DISCONNECTED      0x00000020      /* has been disconnected */
#define MPTSF_MP_CAPABLE        0x00000040      /* connected as a MPTCP subflow */
#define MPTSF_MP_READY          0x00000080      /* MPTCP has been confirmed */
#define MPTSF_MP_DEGRADED       0x00000100      /* has lost its MPTCP capabilities */
#define MPTSF_PREFERRED         0x00000200      /* primary/preferred subflow */
#define MPTSF_SOPT_OLDVAL       0x00000400      /* old option value is valid */
#define MPTSF_SOPT_INPROG       0x00000800      /* sosetopt in progress */
#define MPTSF_FAILINGOVER       0x00001000      /* subflow not used for output */
#define MPTSF_ACTIVE            0x00002000      /* subflow currently in use */
#define MPTSF_MPCAP_CTRSET      0x00004000      /* mpcap counter */
#define MPTSF_CLOSED            0x00008000      /* soclose_locked has been called on this subflow */
#define MPTSF_TFO_REQD          0x00010000      /* TFO requested */
#define MPTSF_CLOSE_REQD        0x00020000      /* A close has been requested from NECP */
#define MPTSF_INITIAL_SUB       0x00040000      /* This is the initial subflow */
#define MPTSF_READ_STALL        0x00080000      /* A read-stall has been detected */
#define MPTSF_WRITE_STALL       0x00100000      /* A write-stall has been detected */
#define MPTSF_FULLY_ESTABLISHED 0x00200000      /* Subflow is fully established and it has been confirmed
	                                         * whether or not it supports MPTCP.
	                                         * No need for further middlebox-detection.
	                                         */
#define MPTSF_CELLICON_SET      0x00400000      /* This subflow set the cellicon */

/*
 * MPTCP states
 * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d
 */
typedef enum mptcp_state {
	MPTCPS_CLOSED           = 0,    /* closed */
	MPTCPS_LISTEN           = 1,    /* not yet implemented */
	MPTCPS_ESTABLISHED      = 2,    /* MPTCP connection established */
	MPTCPS_CLOSE_WAIT       = 3,    /* rcvd DFIN, waiting for close */
	MPTCPS_FIN_WAIT_1       = 4,    /* have closed, sent DFIN */
	MPTCPS_CLOSING          = 5,    /* closed xchd DFIN, waiting DFIN ACK */
	MPTCPS_LAST_ACK         = 6,    /* had DFIN and close; await DFIN ACK */
	MPTCPS_FIN_WAIT_2       = 7,    /* have closed, DFIN is acked */
	MPTCPS_TIME_WAIT        = 8,    /* in 2*MSL quiet wait after close */
	MPTCPS_TERMINATE        = 9,    /* terminal state */
} mptcp_state_t;

/*
 * WiFi Quality states from MPTCP's perspective
 */
typedef enum mptcp_wifi_quality {
	MPTCP_WIFI_QUALITY_GOOD,
	MPTCP_WIFI_QUALITY_BAD,
	MPTCP_WIFI_QUALITY_UNSURE,
} mptcp_wifi_quality_t;

typedef u_int64_t       mptcp_key_t;
typedef u_int32_t       mptcp_token_t;
typedef u_int8_t        mptcp_addr_id;


/* Address ID list */
struct mptcp_subf_auth_entry {
	LIST_ENTRY(mptcp_subf_auth_entry) msae_next;
	u_int32_t       msae_laddr_rand;        /* Local nonce */
	u_int32_t       msae_raddr_rand;        /* Remote nonce */
	mptcp_addr_id   msae_laddr_id;          /* Local addr ID */
	mptcp_addr_id   msae_raddr_id;          /* Remote addr ID */
};

/*
 * MPTCP Protocol Control Block
 *
 * Protected by per-MPTCP mpt_lock.
 * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 */
struct mptcb {
	struct mptses  *mpt_mpte;               /* back ptr to MPTCP session */
	mptcp_state_t   mpt_state;              /* MPTCP state */
	uint32_t        mpt_flags;              /* see flags below */
	uint8_t         mpt_version;            /* MPTCP proto version */
	u_short         mpt_softerror;          /* error not yet reported */
	/*
	 * Authentication and metadata invariants
	 */
	mptcp_key_t     mpt_localkey;           /* in network byte order */
	mptcp_key_t     mpt_remotekey;          /* in network byte order */
	mptcp_token_t   mpt_localtoken;         /* HMAC SHA1 of local key */
	mptcp_token_t   mpt_remotetoken;        /* HMAC SHA1 of remote key */

	/*
	 * Timer vars for scenarios where subflow level acks arrive, but
	 * Data ACKs do not.
	 */
	int             mpt_rxtshift;           /* num of consecutive retrans */
	uint64_t        mpt_rxtstart;           /* time at which rxt started */
	uint64_t        mpt_rtseq;              /* seq # being tracked */
	uint64_t        mpt_timewait;           /* timewait */
	uint32_t        mpt_timer_vals;         /* timer related values */
	/*
	 * Sending side
	 */
	uint64_t        mpt_snduna;             /* DSN of last unacked byte */
	uint64_t        mpt_sndnxt;             /* DSN of next byte to send */
	uint64_t        mpt_sndmax;             /* DSN of max byte sent */
	uint64_t        mpt_local_idsn;         /* First byte's DSN */
	uint32_t        mpt_sndwnd;
	uint64_t        mpt_sndwl1;
	uint64_t        mpt_sndwl2;
	/*
	 * Receiving side
	 */
	uint64_t        mpt_rcvnxt;             /* Next expected DSN */
	uint64_t        mpt_remote_idsn;        /* Peer's IDSN */
	uint64_t        mpt_rcvadv;
	uint32_t        mpt_rcvwnd;
	LIST_HEAD(, mptcp_subf_auth_entry) mpt_subauth_list; /* address IDs */
	/*
	 * Fastclose
	 */
	uint64_t        mpt_dsn_at_csum_fail;   /* MPFail Opt DSN */
	uint32_t        mpt_ssn_at_csum_fail;   /* MPFail Subflow Seq */
	/*
	 * Zombie handling
	 */
#define MPT_GC_TICKS            (30)
#define MPT_GC_TICKS_FAST       (10)
	int32_t         mpt_gc_ticks;           /* Used for zombie deletion */

	uint32_t        mpt_notsent_lowat;      /* TCP_NOTSENT_LOWAT support */

	struct tsegqe_head      mpt_segq;
	uint32_t        mpt_reassqlen;          /* length of reassembly queue */
};

/* valid values for mpt_flags (see also notes on mpts_flags above) */
#define MPTCPF_CHECKSUM                 0x001   /* checksum DSS option */
#define MPTCPF_FALLBACK_TO_TCP          0x002   /* Fallback to TCP */
#define MPTCPF_JOIN_READY               0x004   /* Ready to start 2 or more subflows */
#define MPTCPF_RECVD_MPFAIL             0x008   /* Received MP_FAIL option */
#define MPTCPF_SND_64BITDSN             0x010   /* Send full 64-bit DSN */
#define MPTCPF_SND_64BITACK             0x020   /* Send 64-bit ACK response */
#define MPTCPF_RCVD_64BITACK            0x040   /* Received 64-bit Data ACK */
#define MPTCPF_POST_FALLBACK_SYNC       0x080   /* Post fallback resend data */
#define MPTCPF_FALLBACK_HEURISTIC       0x100   /* Send SYN without MP_CAPABLE due to heuristic */
#define MPTCPF_HEURISTIC_TRAC           0x200   /* Tracked this connection in the heuristics as a failure */
#define MPTCPF_REASS_INPROG             0x400   /* Reassembly is in progress */

/* valid values for mpt_timer_vals */
#define MPTT_REXMT              0x01    /* Starting Retransmit Timer */
#define MPTT_TW                 0x02    /* Starting Timewait Timer */
#define MPTT_FASTCLOSE          0x04    /* Starting Fastclose wait timer */

/* events for close FSM */
#define MPCE_CLOSE              0x1
#define MPCE_RECV_DATA_ACK      0x2
#define MPCE_RECV_DATA_FIN      0x4

/* mptcb manipulation */
static inline struct mptcb *
tptomptp(struct tcpcb *tp)
{
	return tp->t_mptcb;
}

/*
 * MPTCP control block and state structures are allocated along with
 * the MP protocol control block; the folllowing represents the layout.
 */
struct mpp_mtp {
	struct mppcb            mpp;            /* Multipath PCB */
	struct mptses           mpp_ses;        /* MPTCP session */
	struct mptcb            mtcb;           /* MPTCP PCB */
};

#ifdef SYSCTL_DECL
SYSCTL_DECL(_net_inet_mptcp);
#endif /* SYSCTL_DECL */

extern struct mppcbinfo mtcbinfo;
extern struct pr_usrreqs mptcp_usrreqs;
extern os_log_t mptcp_log_handle;

/* Encryption algorithm related definitions */
#define HMAC_TRUNCATED_SYNACK          8
#define HMAC_TRUNCATED_ACK         20
#define HMAC_TRUNCATED_ADD_ADDR         8

/* Mask to obtain 32-bit portion of data sequence number */
#define MPTCP_DATASEQ_LOW32_MASK        (0xffffffff)
#define MPTCP_DATASEQ_LOW32(seq)        (seq & MPTCP_DATASEQ_LOW32_MASK)

/* Mask to obtain upper 32-bit portion of data sequence number */
#define MPTCP_DATASEQ_HIGH32_MASK       (0xffffffff00000000)
#define MPTCP_DATASEQ_HIGH32(seq)       (seq & MPTCP_DATASEQ_HIGH32_MASK)

/* Mask to obtain 32-bit portion of data ack */
#define MPTCP_DATAACK_LOW32_MASK        (0xffffffff)
#define MPTCP_DATAACK_LOW32(ack)        (ack & MPTCP_DATAACK_LOW32_MASK)

/*
 * x is the 64-bit data sequence number, y the 32-bit data seq number to be
 * extended. z is y extended to the appropriate 64-bit value.
 * This algorithm is based on the fact that subflow level window sizes are
 * at the maximum 2**30 (in reality, they are a lot lesser). A high throughput
 * application sending on a large number of subflows can in theory have very
 * large MPTCP level send and receive windows. In which case, 64 bit DSNs
 * must be sent in place of 32 bit DSNs on wire. For us, with 2 subflows at
 * 512K each, sequence wraparound detection can be done by checking whether
 * the 32-bit value obtained on wire is 2**31 bytes apart from the stored
 * lower 32-bits of the Data Sequence Number. Bogus DSNs are dropped by
 * comparing against rwnd. Bogus DSNs within rwnd cannot be protected against
 * and are as weak as bogus TCP sequence numbers.
 */
#define MPTCP_EXTEND_DSN(x, y, z) {                                     \
	if ((MPTCP_DATASEQ_LOW32(x) > y) &&                             \
	    ((((u_int32_t)MPTCP_DATASEQ_LOW32(x)) - (u_int32_t)y) >=    \
	    (u_int32_t)(1U << 31))) {                                    \
	/* \
	 * y wrapped around and x and y are 2**31 bytes  apart \
	 */                                                             \
	        z = MPTCP_DATASEQ_HIGH32(x) + 0x100000000;              \
	        z |= y;                                                 \
	} else if ((MPTCP_DATASEQ_LOW32(x) < y) &&                      \
	    (((u_int32_t)y -                                            \
	    ((u_int32_t)MPTCP_DATASEQ_LOW32(x))) >=                     \
	    (u_int32_t)(1U << 31))) {                                    \
	/* \
	 * x wrapped around and x and y are 2**31 apart \
	 */                                                             \
	        z = MPTCP_DATASEQ_HIGH32(x) - 0x100000000;              \
	        z |= y;                                                 \
	} else {                                                        \
	        z = MPTCP_DATASEQ_HIGH32(x) | y;                        \
	}                                                               \
}

extern int mptcp_enable;        /* Multipath TCP */
extern int mptcp_mpcap_retries; /* Multipath TCP retries */
extern int mptcp_join_retries;  /* Multipath TCP Join retries */
extern int mptcp_dss_csum;      /* Multipath DSS Option checksum */
extern int mptcp_fail_thresh;   /* Multipath failover thresh of retransmits */
extern int mptcp_subflow_keeptime; /* Multipath subflow TCP_KEEPALIVE opt */
extern int mptcp_developer_mode;        /* Allow aggregation mode */
extern uint32_t mptcp_cellicon_refcount;
extern uint32_t mptcp_enable_v1;

#define MPTCP_CELLICON_TOGGLE_RATE      (5 * TCP_RETRANSHZ) /* Only toggle every 5 seconds */

extern int tcp_jack_rxmt;       /* Join ACK retransmission value in msecs */

extern int mptcp_reass_total_qlen;

__BEGIN_DECLS
extern void mptcp_init(struct protosw *, struct domain *);
extern int mptcp_ctloutput(struct socket *, struct sockopt *);
extern int mptcp_session_create(struct mppcb *);
extern boolean_t mptcp_ok_to_create_subflows(struct mptcb *mp_tp);
extern void mptcp_check_subflows_and_add(struct mptses *mpte);
extern void mptcp_check_subflows_and_remove(struct mptses *mpte);
extern void mptcpstats_inc_switch(struct mptses *mpte, const struct mptsub *mpts);
extern void mptcpstats_update(struct mptcp_itf_stats *stats, const struct mptsub *mpts);
extern int mptcpstats_get_index_by_ifindex(struct mptcp_itf_stats *stats, u_short ifindex, boolean_t create);
extern struct mptses *mptcp_drop(struct mptses *mpte, struct mptcb *mp_tp, u_short errno);
extern struct mptses *mptcp_close(struct mptses *, struct mptcb *);
extern int mptcp_lock(struct socket *, int, void *);
extern int mptcp_unlock(struct socket *, int, void *);
extern lck_mtx_t *mptcp_getlock(struct socket *, int);
extern void mptcp_subflow_workloop(struct mptses *);

extern void mptcp_sched_create_subflows(struct mptses *);

extern void mptcp_finish_usrclosed(struct mptses *mpte);
extern struct mptopt *mptcp_sopt_alloc(zalloc_flags_t);
extern const char *mptcp_sopt2str(int, int);
extern void mptcp_sopt_free(struct mptopt *);
extern void mptcp_sopt_insert(struct mptses *, struct mptopt *);
extern void mptcp_sopt_remove(struct mptses *, struct mptopt *);
extern struct mptopt *mptcp_sopt_find(struct mptses *, struct sockopt *);

extern int mptcp_subflow_add(struct mptses *, struct sockaddr *,
    struct sockaddr *, uint32_t, sae_connid_t *);
extern void mptcp_subflow_del(struct mptses *, struct mptsub *);

extern void mptcp_handle_input(struct socket *so);
#define MPTCP_SUBOUT_PROBING    0x01
extern int mptcp_subflow_output(struct mptses *mpte, struct mptsub *mpts, int flags);
extern void mptcp_clean_reinjectq(struct mptses *mpte);
extern void mptcp_subflow_shutdown(struct mptses *, struct mptsub *);
extern void mptcp_subflow_disconnect(struct mptses *, struct mptsub *);
extern int mptcp_subflow_sosetopt(struct mptses *, struct mptsub *,
    struct mptopt *);
extern int mptcp_subflow_sogetopt(struct mptses *, struct socket *,
    struct mptopt *);

extern void mptcp_input(struct mptses *, struct mbuf *);
extern boolean_t mptcp_can_send_more(struct mptcb *mp_tp, boolean_t ignore_reinject);
extern int mptcp_output(struct mptses *);
extern void mptcp_close_fsm(struct mptcb *, uint32_t);

extern void mptcp_hmac_sha1(mptcp_key_t, mptcp_key_t, u_int32_t, u_int32_t,
    u_char*);
extern void mptcp_hmac_sha256(mptcp_key_t, mptcp_key_t, u_char*, uint16_t,
    u_char*);
extern void mptcp_get_mpjoin_hmac(mptcp_addr_id, struct mptcb *, u_char *, uint8_t);
extern void mptcp_get_rands(mptcp_addr_id, struct mptcb *, u_int32_t *,
    u_int32_t *);
extern void mptcp_set_raddr_rand(mptcp_addr_id, struct mptcb *, mptcp_addr_id,
    u_int32_t);
extern int mptcp_init_remote_parms(struct mptcb *);
extern boolean_t mptcp_ok_to_keepalive(struct mptcb *);
extern void mptcp_insert_dsn(struct mppcb *, struct mbuf *);
extern void mptcp_output_getm_dsnmap32(struct socket *so, int off,
    uint32_t *dsn, uint32_t *relseq,
    uint16_t *data_len, uint16_t *dss_csum);
extern void mptcp_output_getm_dsnmap64(struct socket *so, int off,
    uint64_t *dsn, uint32_t *relseq,
    uint16_t *data_len, uint16_t *dss_csum);
extern void mptcp_output_getm_data_level_details(struct socket *so, int off,
    uint16_t *data_len, uint16_t *dss_csum);
extern void mptcp_act_on_txfail(struct socket *);
extern struct mptsub *mptcp_get_subflow(struct mptses *mpte, struct mptsub **preferred);
extern int mptcp_get_map_for_dsn(struct socket *so, uint64_t dsn_fail, uint32_t *tcp_seq);
extern int32_t mptcp_adj_sendlen(struct socket *so, int32_t off);
extern void mptcp_sbrcv_grow(struct mptcb *mp_tp);
extern int32_t mptcp_sbspace(struct mptcb *);
extern void mptcp_notify_mpready(struct socket *);
extern void mptcp_notify_mpfail(struct socket *);
extern void mptcp_notify_close(struct socket *);
extern boolean_t mptcp_no_rto_spike(struct socket*);
extern int mptcp_set_notsent_lowat(struct mptses *mpte, int optval);
extern u_int32_t mptcp_get_notsent_lowat(struct mptses *mpte);
extern int mptcp_notsent_lowat_check(struct socket *so);
extern void mptcp_ask_symptoms(struct mptses *mpte);
extern void mptcp_control_register(void);
extern mptcp_wifi_quality_t mptcp_wifi_quality_for_session(struct mptses *mpte);
extern boolean_t symptoms_is_wifi_lossy(void);
extern void mptcp_session_necp_cb(void *, int, uint32_t, uint32_t, bool *);
extern struct sockaddr *mptcp_get_session_dst(struct mptses *mpte,
    boolean_t has_v6, boolean_t has_v4);
extern void mptcp_set_restrictions(struct socket *mp_so);
extern void mptcp_clear_cellicon(void);
extern void mptcp_unset_cellicon(struct mptses *mpte, struct mptsub *mpts, uint32_t val);
extern void mptcp_reset_rexmit_state(struct tcpcb *tp);
extern void mptcp_reset_keepalive(struct tcpcb *tp);
extern int mptcp_validate_csum(struct tcpcb *tp, struct mbuf *m, uint64_t dsn,
    uint32_t sseq, uint16_t dlen, uint16_t csum, int dfin);
__END_DECLS

#endif /* BSD_KERNEL_PRIVATE */
#ifdef PRIVATE

typedef struct mptcp_flow {
	uint64_t                flow_len;
	uint64_t                flow_tcpci_offset;
	uint32_t                flow_flags;
	sae_connid_t            flow_cid;
	struct sockaddr_storage flow_src;
	struct sockaddr_storage flow_dst;
	uint32_t                flow_relseq;    /* last subflow rel seq# */
	int32_t                 flow_soerror;   /* subflow level error */
	uint32_t                flow_probecnt;  /* number of probes sent */
	conninfo_tcp_t          flow_ci;        /* must be the last field */
} mptcp_flow_t;

typedef struct conninfo_mptcp {
	uint64_t        mptcpci_len;
	uint64_t        mptcpci_flow_offset;    /* offsetof first flow */
	uint64_t        mptcpci_nflows;         /* number of subflows */
	uint32_t        mptcpci_state;          /* MPTCP level state */
	uint32_t        mptcpci_mpte_flags;     /* Session flags */
	uint32_t        mptcpci_flags;          /* MPTCB flags */
	uint32_t        mptcpci_ltoken;         /* local token */
	uint32_t        mptcpci_rtoken;         /* remote token */
	uint32_t        mptcpci_notsent_lowat;  /* NOTSENT_LOWAT */

	/* Send side */
	uint64_t        mptcpci_snduna;         /* DSN of last unacked byte */
	uint64_t        mptcpci_sndnxt;         /* DSN of next byte to send */
	uint64_t        mptcpci_sndmax;         /* DSN of max byte sent */
	uint64_t        mptcpci_lidsn;          /* Local IDSN */
	uint32_t        mptcpci_sndwnd;         /* Send window snapshot */

	/* Receive side */
	uint64_t        mptcpci_rcvnxt;         /* Next expected DSN */
	uint64_t        mptcpci_rcvatmark;      /* Session level rcvnxt */
	uint64_t        mptcpci_ridsn;          /* Peer's IDSN */
	uint32_t        mptcpci_rcvwnd;         /* Receive window */

	uint8_t         mptcpci_mpte_addrid;    /* last addr id */

	mptcp_flow_t    mptcpci_flows[1];
} conninfo_mptcp_t;

/* Use SymptomsD notifications of wifi and cell status in subflow selection */
#define MPTCP_KERN_CTL_NAME    "com.apple.network.advisory"
typedef struct symptoms_advisory {
	union {
		uint32_t        sa_nwk_status_int;
		struct {
			union {
#define SYMPTOMS_ADVISORY_NOCOMMENT     0x0000
#define SYMPTOMS_ADVISORY_USEAPP        0xFFFF /* Very ugly workaround to avoid breaking backwards compatibility - ToDo: Fix it in +1 */
				uint16_t        sa_nwk_status;
				struct {
#define SYMPTOMS_ADVISORY_WIFI_BAD     0x01
#define SYMPTOMS_ADVISORY_WIFI_OK      0x02
					uint8_t sa_wifi_status;
#define SYMPTOMS_ADVISORY_CELL_BAD     0x01
#define SYMPTOMS_ADVISORY_CELL_OK      0x02
					uint8_t sa_cell_status;
				};
			};
			uint16_t        sa_unused;
		};
	};
} symptoms_advisory_t;

#define MPTCP_TARGET_BASED_RSSI_THRESHOLD -75
struct mptcp_symptoms_answer {
	struct symptoms_advisory advisory;
	uuid_t  uuid;
	int32_t rssi;
};

struct mptcp_symptoms_ask_uuid {
	uint32_t        cmd;
#define MPTCP_SYMPTOMS_ASK_UUID         1
	uuid_t          uuid;
	uint32_t        priority;
#define MPTCP_SYMPTOMS_UNKNOWN          0
#define MPTCP_SYMPTOMS_BACKGROUND       1
#define MPTCP_SYMPTOMS_FOREGROUND       2
};

struct kev_mptcp_data {
	int value;
};

#endif /* PRIVATE */
#endif /* _NETINET_MPTCP_VAR_H_ */