xref: /xnu-8019.80.24/bsd/netinet/mptcp_var.h (revision a325d9c4a84054e40bbe985afedcb50ab80993ea)
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28 
29 #ifndef _NETINET_MPTCP_VAR_H_
30 #define _NETINET_MPTCP_VAR_H_
31 
32 #ifdef PRIVATE
33 #include <netinet/in.h>
34 #include <netinet/tcp.h>
35 #endif
36 
37 #ifdef BSD_KERNEL_PRIVATE
38 #include <sys/queue.h>
39 #include <sys/protosw.h>
40 #include <kern/locks.h>
41 #include <mach/boolean.h>
42 #include <netinet/mp_pcb.h>
43 #include <netinet/tcp_var.h>
44 #include <os/log.h>
45 
46 struct mpt_itf_info {
47 	uint32_t ifindex;
48 	uint32_t has_v4_conn:1,
49 	    has_v6_conn:1,
50 	    has_nat64_conn:1,
51 	    no_mptcp_support:1;
52 };
53 
54 /*
55  * MPTCP Session
56  *
57  * This is an extension to the multipath PCB specific for MPTCP, protected by
58  * the per-PCB mpp_lock (also the socket's lock);
59  */
60 struct mptses {
61 	struct mppcb    *mpte_mppcb;            /* back ptr to multipath PCB */
62 	struct mptcb    *mpte_mptcb;            /* ptr to MPTCP PCB */
63 	TAILQ_HEAD(, mptopt) mpte_sopts;        /* list of socket options */
64 	TAILQ_HEAD(, mptsub) mpte_subflows;     /* list of subflows */
65 #define MPTCP_MAX_NUM_SUBFLOWS 256
66 	uint16_t        mpte_numflows;          /* # of subflows in list */
67 	uint16_t        mpte_nummpcapflows;     /* # of MP_CAP subflows */
68 	sae_associd_t   mpte_associd;           /* MPTCP association ID */
69 	sae_connid_t    mpte_connid_last;       /* last used connection ID */
70 
71 	uint64_t        mpte_time_target;
72 	thread_call_t   mpte_time_thread;
73 
74 	uint32_t        mpte_last_cellicon_set;
75 	uint32_t        mpte_cellicon_increments;
76 
77 	union {
78 		/* Source address of initial subflow */
79 		struct sockaddr _mpte_src;
80 		struct sockaddr_in _mpte_src_v4;
81 		struct sockaddr_in6 _mpte_src_v6;
82 	} mpte_u_src;
83 #define mpte_src mpte_u_src._mpte_src
84 #define __mpte_src_v4 mpte_u_src._mpte_src_v4
85 #define __mpte_src_v6 mpte_u_src._mpte_src_v6
86 	union {
87 		/* Destination address of initial subflow */
88 		struct sockaddr _mpte_dst;
89 		struct sockaddr_in _mpte_dst_v4;
90 		struct sockaddr_in6 _mpte_dst_v6;
91 	} mpte_u_dst;
92 #define mpte_dst mpte_u_dst._mpte_dst
93 #define __mpte_dst_v4 mpte_u_dst._mpte_dst_v4
94 #define __mpte_dst_v6 mpte_u_dst._mpte_dst_v6
95 
96 	struct sockaddr_in      mpte_sub_dst_v4;
97 	struct sockaddr_in6     mpte_sub_dst_v6;
98 	uint8_t         sub_dst_addr_id_v4;
99 	uint8_t         sub_dst_addr_id_v6;
100 
101 	uint16_t        mpte_alternate_port;    /* Alternate port for subflow establishment (network-byte-order) */
102 
103 	int mpte_epid;
104 	uuid_t mpte_euuid;
105 
106 	struct mptsub   *mpte_active_sub;       /* ptr to last active subf */
107 	uint16_t mpte_flags;                    /* per mptcp session flags */
108 #define MPTE_SND_REM_ADDR       0x01            /* Send Remove_addr option */
109 #define MPTE_SVCTYPE_CHECKED    0x02            /* Did entitlement-check for service-type */
110 #define MPTE_FIRSTPARTY         0x04            /* First-party app used multipath_extended entitlement */
111 #define MPTE_ACCESS_GRANTED     0x08            /* Access to cellular has been granted for this connection */
112 #define MPTE_FORCE_ENABLE       0x10            /* For MPTCP regardless of heuristics to detect middleboxes */
113 #define MPTE_IN_WORKLOOP        0x20            /* Are we currently inside the workloop ? */
114 #define MPTE_WORKLOOP_RELAUNCH  0x40            /* Another event got queued, we should restart the workloop */
115 #define MPTE_UNICAST_IP         0x80            /* New subflows are only being established towards the unicast IP in the ADD_ADDR */
116 #define MPTE_CELL_PROHIBITED    0x100           /* Cell access has been prohibited based on signal quality */
117 #define MPTE_FORCE_V0           0x200           /* Force MPTCP to use version 0 regradless of tcp cache */
118 #define MPTE_FORCE_V1           0x400           /* Force MPTCP to use version 1 regradless of tcp cache */
119 	uint8_t mpte_svctype;                   /* MPTCP Service type */
120 	uint8_t mpte_lost_aid;                  /* storing lost address id */
121 	uint8_t mpte_addrid_last;               /* storing address id parm */
122 
123 #define MPTE_ITFINFO_SIZE       4
124 	uint32_t        mpte_itfinfo_size;
125 	struct mpt_itf_info     _mpte_itfinfo[MPTE_ITFINFO_SIZE];
126 	struct mpt_itf_info     *mpte_itfinfo;
127 
128 	struct mbuf             *mpte_reinjectq;
129 
130 	/* The below is used for stats */
131 	uint32_t        mpte_subflow_switches;  /* Number of subflow-switches in sending */
132 	uint32_t        mpte_used_cell:1,
133 	    mpte_used_wifi:1,
134 	    mpte_initial_cell:1,
135 	    mpte_triggered_cell,
136 	    mpte_handshake_success:1,
137 	    mpte_last_added_addr_is_v4:1;
138 
139 	struct mptcp_itf_stats  mpte_itfstats[MPTCP_ITFSTATS_SIZE];
140 	uint64_t                mpte_init_txbytes __attribute__((aligned(8)));
141 	uint64_t                mpte_init_rxbytes __attribute__((aligned(8)));
142 };
143 
144 static inline struct socket *
mptetoso(struct mptses * mpte)145 mptetoso(struct mptses *mpte)
146 {
147 	return mpte->mpte_mppcb->mpp_socket;
148 }
149 
150 static inline struct mptses *
mptompte(struct mppcb * mp)151 mptompte(struct mppcb *mp)
152 {
153 	return (struct mptses *)mp->mpp_pcbe;
154 }
155 
156 static inline struct mptses *
mpsotompte(struct socket * so)157 mpsotompte(struct socket *so)
158 {
159 	return mptompte(mpsotomppcb(so));
160 }
161 
162 static inline boolean_t
mpp_try_lock(struct mppcb * mp)163 mpp_try_lock(struct mppcb *mp)
164 {
165 	if (!lck_mtx_try_lock(&mp->mpp_lock)) {
166 		return false;
167 	}
168 
169 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
170 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
171 
172 	return true;
173 }
174 
175 static inline void
mpp_lock(struct mppcb * mp)176 mpp_lock(struct mppcb *mp)
177 {
178 	lck_mtx_lock(&mp->mpp_lock);
179 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
180 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
181 }
182 
183 static inline void
mpp_unlock(struct mppcb * mp)184 mpp_unlock(struct mppcb *mp)
185 {
186 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
187 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
188 	lck_mtx_unlock(&mp->mpp_lock);
189 }
190 
191 static inline lck_mtx_t *
mpp_getlock(struct mppcb * mp,int flags)192 mpp_getlock(struct mppcb *mp, int flags)
193 {
194 	if (flags & PR_F_WILLUNLOCK) {
195 		VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
196 		VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
197 	}
198 
199 	return &mp->mpp_lock;
200 }
201 
202 static inline int
mptcp_subflow_cwnd_space(struct socket * so)203 mptcp_subflow_cwnd_space(struct socket *so)
204 {
205 	struct tcpcb *tp = sototcpcb(so);
206 	int cwnd = (int)(MIN(tp->snd_wnd, tp->snd_cwnd) - (so->so_snd.sb_cc));
207 
208 	return MIN(cwnd, sbspace(&so->so_snd));
209 }
210 
211 static inline bool
mptcp_subflows_need_backup_flag(struct mptses * mpte)212 mptcp_subflows_need_backup_flag(struct mptses *mpte)
213 {
214 	return mpte->mpte_svctype < MPTCP_SVCTYPE_AGGREGATE ||
215 	       mpte->mpte_svctype == MPTCP_SVCTYPE_PURE_HANDOVER;
216 }
217 
218 /*
219  * MPTCP socket options
220  */
221 struct mptopt {
222 	TAILQ_ENTRY(mptopt)     mpo_entry;      /* glue to other options */
223 	uint32_t                mpo_flags;      /* see flags below */
224 	int                     mpo_level;      /* sopt_level */
225 	int                     mpo_name;       /* sopt_name */
226 	int                     mpo_intval;     /* sopt_val */
227 };
228 
229 #define MPOF_ATTACHED           0x1     /* attached to MP socket */
230 #define MPOF_SUBFLOW_OK         0x2     /* can be issued on subflow socket */
231 #define MPOF_INTERIM            0x4     /* has not been issued on any subflow */
232 
233 /*
234  * MPTCP subflow
235  *
236  * Note that mpts_flags and mpts_evctl are modified via atomic operations.
237  */
238 struct mptsub {
239 	TAILQ_ENTRY(mptsub)   mpts_entry;     /* glue to peer subflows */
240 	uint32_t              mpts_refcnt;    /* reference count */
241 	uint32_t              mpts_flags;     /* see flags below */
242 	long                  mpts_evctl;     /* subflow control events */
243 	sae_connid_t          mpts_connid;    /* subflow connection ID */
244 	int                   mpts_oldintval; /* sopt_val before sosetopt  */
245 	struct mptses         *mpts_mpte;     /* back ptr to MPTCP session */
246 	struct socket         *mpts_socket;   /* subflow socket */
247 	struct sockaddr       *mpts_src;      /* source address */
248 
249 	union {
250 		/* destination address */
251 		struct sockaddr         _mpts_dst;
252 		struct sockaddr_in      _mpts_dst_v4;
253 		struct sockaddr_in6     _mpts_dst_v6;
254 	} mpts_u_dst;
255 #define mpts_dst mpts_u_dst._mpts_dst
256 #define __mpts_dst_v4 mpts_u_dst._mpts_dst_v4
257 #define __mpts_dst_v6 mpts_u_dst._mpts_dst_v6
258 	u_int32_t               mpts_rel_seq;   /* running count of subflow # */
259 	u_int32_t               mpts_iss;       /* Initial sequence number, taking TFO into account */
260 	u_int32_t               mpts_ifscope;   /* scoped to the interface */
261 	uint32_t                mpts_probesoon; /* send probe after probeto */
262 	uint32_t                mpts_probecnt;  /* number of probes sent */
263 	uint32_t                mpts_maxseg;    /* cached value of t_maxseg */
264 };
265 
266 /*
267  * Valid values for mpts_flags.  In particular:
268  *
269  *    - MP_CAPABLE means that the connection is successfully established as
270  *	MPTCP and data transfer may occur, but is not yet ready for multipath-
271  *	related semantics until MP_READY.  I.e. if this is on the first subflow,
272  *	it causes the MPTCP socket to transition to a connected state, except
273  *	that additional subflows will not be established; they will be marked
274  *	with PENDING and will be processed when the first subflow is marked
275  *	with MP_READY.
276  *
277  *    - MP_READY implies that an MP_CAPABLE connection has been confirmed as
278  *	an MPTCP connection.  See notes above.
279  *
280  *    - MP_DEGRADED implies that the connection has lost its MPTCP capabilities
281  *	but data transfer on the MPTCP socket is unaffected.  Any existing
282  *	PENDING subflows will be disconnected, and further attempts to connect
283  *	additional subflows will be rejected.
284  *
285  * Note that these are per-subflow flags.  The setting and clearing of MP_READY
286  * reflects the state of the MPTCP connection with regards to its multipath
287  * semantics, via the MPTCPF_JOIN_READY flag.  Until that flag is set (meaning
288  * until at least a subflow is marked with MP_READY), further connectx(2)
289  * attempts to join will be queued.  When the flag is cleared (after it has
290  * been set), further connectx(2) will fail (and existing queued ones will be
291  * aborted) and the MPTCP connection loses all of its multipath semantics.
292  *
293  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
294  */
295 #define MPTSF_ATTACHED          0x00000001      /* attached to MPTCP PCB */
296 #define MPTSF_CONNECTING        0x00000002      /* connection was attempted */
297 #define MPTSF_CONNECT_PENDING   0x00000004      /* will connect when MPTCP is ready */
298 #define MPTSF_CONNECTED         0x00000008      /* connection is established */
299 #define MPTSF_DISCONNECTING     0x00000010      /* disconnection was attempted */
300 #define MPTSF_DISCONNECTED      0x00000020      /* has been disconnected */
301 #define MPTSF_MP_CAPABLE        0x00000040      /* connected as a MPTCP subflow */
302 #define MPTSF_MP_READY          0x00000080      /* MPTCP has been confirmed */
303 #define MPTSF_MP_DEGRADED       0x00000100      /* has lost its MPTCP capabilities */
304 #define MPTSF_PREFERRED         0x00000200      /* primary/preferred subflow */
305 #define MPTSF_SOPT_OLDVAL       0x00000400      /* old option value is valid */
306 #define MPTSF_SOPT_INPROG       0x00000800      /* sosetopt in progress */
307 #define MPTSF_FAILINGOVER       0x00001000      /* subflow not used for output */
308 #define MPTSF_ACTIVE            0x00002000      /* subflow currently in use */
309 #define MPTSF_MPCAP_CTRSET      0x00004000      /* mpcap counter */
310 #define MPTSF_CLOSED            0x00008000      /* soclose_locked has been called on this subflow */
311 #define MPTSF_TFO_REQD          0x00010000      /* TFO requested */
312 #define MPTSF_CLOSE_REQD        0x00020000      /* A close has been requested from NECP */
313 #define MPTSF_INITIAL_SUB       0x00040000      /* This is the initial subflow */
314 #define MPTSF_READ_STALL        0x00080000      /* A read-stall has been detected */
315 #define MPTSF_WRITE_STALL       0x00100000      /* A write-stall has been detected */
316 #define MPTSF_FULLY_ESTABLISHED 0x00200000      /* Subflow is fully established and it has been confirmed
317 	                                         * whether or not it supports MPTCP.
318 	                                         * No need for further middlebox-detection.
319 	                                         */
320 #define MPTSF_CELLICON_SET      0x00400000      /* This subflow set the cellicon */
321 
322 #define MPTSF_BITS \
323 	"\020\1ATTACHED\2CONNECTING\3PENDING\4CONNECTED\5DISCONNECTING" \
324 	"\6DISCONNECTED\7MP_CAPABLE\10MP_READY\11MP_DEGRADED" \
325 	"\12PREFERRED\13SOPT_OLDVAL" \
326 	"\14SOPT_INPROG\15FAILINGOVER\16ACTIVE\17MPCAP_CTRSET" \
327 	"\20CLOSED\21TFO_REQD\22CLOSEREQD\23INITIALSUB\24READ_STALL" \
328 	"\25WRITE_STALL\26CONFIRMED"
329 
330 /*
331  * MPTCP states
332  * Keep in sync with bsd/dev/dtrace/mptcp.d
333  */
334 typedef enum mptcp_state {
335 	MPTCPS_CLOSED           = 0,    /* closed */
336 	MPTCPS_LISTEN           = 1,    /* not yet implemented */
337 	MPTCPS_ESTABLISHED      = 2,    /* MPTCP connection established */
338 	MPTCPS_CLOSE_WAIT       = 3,    /* rcvd DFIN, waiting for close */
339 	MPTCPS_FIN_WAIT_1       = 4,    /* have closed, sent DFIN */
340 	MPTCPS_CLOSING          = 5,    /* closed xchd DFIN, waiting DFIN ACK */
341 	MPTCPS_LAST_ACK         = 6,    /* had DFIN and close; await DFIN ACK */
342 	MPTCPS_FIN_WAIT_2       = 7,    /* have closed, DFIN is acked */
343 	MPTCPS_TIME_WAIT        = 8,    /* in 2*MSL quiet wait after close */
344 	MPTCPS_TERMINATE        = 9,    /* terminal state */
345 } mptcp_state_t;
346 
347 typedef u_int64_t       mptcp_key_t;
348 typedef u_int32_t       mptcp_token_t;
349 typedef u_int8_t        mptcp_addr_id;
350 
351 
352 /* Address ID list */
353 struct mptcp_subf_auth_entry {
354 	LIST_ENTRY(mptcp_subf_auth_entry) msae_next;
355 	u_int32_t       msae_laddr_rand;        /* Local nonce */
356 	u_int32_t       msae_raddr_rand;        /* Remote nonce */
357 	mptcp_addr_id   msae_laddr_id;          /* Local addr ID */
358 	mptcp_addr_id   msae_raddr_id;          /* Remote addr ID */
359 };
360 
361 /*
362  * MPTCP Protocol Control Block
363  *
364  * Protected by per-MPTCP mpt_lock.
365  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
366  */
367 struct mptcb {
368 	struct mptses  *mpt_mpte;               /* back ptr to MPTCP session */
369 	mptcp_state_t   mpt_state;              /* MPTCP state */
370 	uint32_t        mpt_flags;              /* see flags below */
371 	uint8_t         mpt_version;            /* MPTCP proto version */
372 	uint8_t         mpt_peer_version;       /* Version from peer */
373 	u_short         mpt_softerror;          /* error not yet reported */
374 	/*
375 	 * Authentication and metadata invariants
376 	 */
377 	mptcp_key_t     mpt_localkey;           /* in network byte order */
378 	mptcp_key_t     mpt_remotekey;          /* in network byte order */
379 	mptcp_token_t   mpt_localtoken;         /* HMAC SHA1 of local key */
380 	mptcp_token_t   mpt_remotetoken;        /* HMAC SHA1 of remote key */
381 
382 	/*
383 	 * Timer vars for scenarios where subflow level acks arrive, but
384 	 * Data ACKs do not.
385 	 */
386 	int             mpt_rxtshift;           /* num of consecutive retrans */
387 	uint64_t        mpt_rxtstart;           /* time at which rxt started */
388 	uint64_t        mpt_rtseq;              /* seq # being tracked */
389 	uint64_t        mpt_timewait;           /* timewait */
390 	uint32_t        mpt_timer_vals;         /* timer related values */
391 	/*
392 	 * Sending side
393 	 */
394 	uint64_t        mpt_snduna;             /* DSN of last unacked byte */
395 	uint64_t        mpt_sndnxt;             /* DSN of next byte to send */
396 	uint64_t        mpt_sndmax;             /* DSN of max byte sent */
397 	uint64_t        mpt_local_idsn;         /* First byte's DSN */
398 	uint32_t        mpt_sndwnd;
399 	uint64_t        mpt_sndwl1;
400 	uint64_t        mpt_sndwl2;
401 	/*
402 	 * Receiving side
403 	 */
404 	uint64_t        mpt_rcvnxt;             /* Next expected DSN */
405 	uint64_t        mpt_remote_idsn;        /* Peer's IDSN */
406 	uint64_t        mpt_rcvadv;
407 	uint32_t        mpt_rcvwnd;
408 	LIST_HEAD(, mptcp_subf_auth_entry) mpt_subauth_list; /* address IDs */
409 	/*
410 	 * Fastclose
411 	 */
412 	uint64_t        mpt_dsn_at_csum_fail;   /* MPFail Opt DSN */
413 	uint32_t        mpt_ssn_at_csum_fail;   /* MPFail Subflow Seq */
414 	/*
415 	 * Zombie handling
416 	 */
417 #define MPT_GC_TICKS            (30)
418 #define MPT_GC_TICKS_FAST       (10)
419 	int32_t         mpt_gc_ticks;           /* Used for zombie deletion */
420 
421 	uint32_t        mpt_notsent_lowat;      /* TCP_NOTSENT_LOWAT support */
422 
423 	struct tsegqe_head      mpt_segq;
424 	uint32_t        mpt_reassqlen;          /* length of reassembly queue */
425 };
426 
427 /* valid values for mpt_flags (see also notes on mpts_flags above) */
428 #define MPTCPF_CHECKSUM                 0x001   /* checksum DSS option */
429 #define MPTCPF_FALLBACK_TO_TCP          0x002   /* Fallback to TCP */
430 #define MPTCPF_JOIN_READY               0x004   /* Ready to start 2 or more subflows */
431 #define MPTCPF_RECVD_MPFAIL             0x008   /* Received MP_FAIL option */
432 #define MPTCPF_SND_64BITDSN             0x010   /* Send full 64-bit DSN */
433 #define MPTCPF_SND_64BITACK             0x020   /* Send 64-bit ACK response */
434 #define MPTCPF_RCVD_64BITACK            0x040   /* Received 64-bit Data ACK */
435 #define MPTCPF_POST_FALLBACK_SYNC       0x080   /* Post fallback resend data */
436 #define MPTCPF_FALLBACK_HEURISTIC       0x100   /* Send SYN without MP_CAPABLE due to heuristic */
437 #define MPTCPF_HEURISTIC_TRAC           0x200   /* Tracked this connection in the heuristics as a failure */
438 #define MPTCPF_REASS_INPROG             0x400   /* Reassembly is in progress */
439 #define MPTCPF_UNICAST_IP               0x800
440 
441 #define MPTCPF_BITS \
442 	"\020\1CHECKSUM\2FALLBACK_TO_TCP\3JOIN_READY\4RECVD_MPFAIL" \
443 	"\5SND_64BITDSN\6SND_64BITACK\7RCVD_64BITACK\10POST_FALLBACK_SYNC" \
444 	"\11FALLBACK_HEURISTIC\12HEURISTIC_TRAC\13REASS_INPROG"
445 
446 /* valid values for mpt_timer_vals */
447 #define MPTT_REXMT              0x01    /* Starting Retransmit Timer */
448 #define MPTT_TW                 0x02    /* Starting Timewait Timer */
449 #define MPTT_FASTCLOSE          0x04    /* Starting Fastclose wait timer */
450 
451 /* events for close FSM */
452 #define MPCE_CLOSE              0x1
453 #define MPCE_RECV_DATA_ACK      0x2
454 #define MPCE_RECV_DATA_FIN      0x4
455 
456 /* mptcb manipulation */
457 static inline struct mptcb *
tptomptp(struct tcpcb * tp)458 tptomptp(struct tcpcb *tp)
459 {
460 	return tp->t_mptcb;
461 }
462 
463 /*
464  * MPTCP control block and state structures are allocated along with
465  * the MP protocol control block; the folllowing represents the layout.
466  */
467 struct mpp_mtp {
468 	struct mppcb            mpp;            /* Multipath PCB */
469 	struct mptses           mpp_ses;        /* MPTCP session */
470 	struct mptcb            mtcb;           /* MPTCP PCB */
471 };
472 
473 #ifdef SYSCTL_DECL
474 SYSCTL_DECL(_net_inet_mptcp);
475 #endif /* SYSCTL_DECL */
476 
477 extern struct mppcbinfo mtcbinfo;
478 extern struct pr_usrreqs mptcp_usrreqs;
479 extern os_log_t mptcp_log_handle;
480 
481 /* Encryption algorithm related definitions */
482 #define HMAC_TRUNCATED_SYNACK          8
483 #define HMAC_TRUNCATED_ACK         20
484 #define HMAC_TRUNCATED_ADD_ADDR         8
485 
486 /* MPTCP Debugging Levels */
487 #define MPTCP_LOGLVL_NONE       0x0     /* No debug logging */
488 #define MPTCP_LOGLVL_ERR        0x1     /* Errors in execution are logged */
489 #define MPTCP_LOGLVL_LOG        0x2     /* Important logs */
490 #define MPTCP_LOGLVL_VERBOSE    0x4     /* Verbose logs */
491 
492 /* MPTCP sub-components for debug logging */
493 #define MPTCP_NO_DBG            0x00    /* No areas are logged */
494 #define MPTCP_STATE_DBG         0x01    /* State machine logging */
495 #define MPTCP_SOCKET_DBG        0x02    /* Socket call logging */
496 #define MPTCP_SENDER_DBG        0x04    /* Sender side logging */
497 #define MPTCP_RECEIVER_DBG      0x08    /* Receiver logging */
498 #define MPTCP_EVENTS_DBG        0x10    /* Subflow events logging */
499 
500 /* Mask to obtain 32-bit portion of data sequence number */
501 #define MPTCP_DATASEQ_LOW32_MASK        (0xffffffff)
502 #define MPTCP_DATASEQ_LOW32(seq)        (seq & MPTCP_DATASEQ_LOW32_MASK)
503 
504 /* Mask to obtain upper 32-bit portion of data sequence number */
505 #define MPTCP_DATASEQ_HIGH32_MASK       (0xffffffff00000000)
506 #define MPTCP_DATASEQ_HIGH32(seq)       (seq & MPTCP_DATASEQ_HIGH32_MASK)
507 
508 /* Mask to obtain 32-bit portion of data ack */
509 #define MPTCP_DATAACK_LOW32_MASK        (0xffffffff)
510 #define MPTCP_DATAACK_LOW32(ack)        (ack & MPTCP_DATAACK_LOW32_MASK)
511 
512 /* Mask to obtain upper 32-bit portion of data ack */
513 #define MPTCP_DATAACK_HIGH32_MASK       (0xffffffff00000000)
514 #define MPTCP_DATAACK_HIGH32(ack)       (ack & MPTCP_DATAACK_HIGH32_MASK)
515 
516 /*
517  * x is the 64-bit data sequence number, y the 32-bit data seq number to be
518  * extended. z is y extended to the appropriate 64-bit value.
519  * This algorithm is based on the fact that subflow level window sizes are
520  * at the maximum 2**30 (in reality, they are a lot lesser). A high throughput
521  * application sending on a large number of subflows can in theory have very
522  * large MPTCP level send and receive windows. In which case, 64 bit DSNs
523  * must be sent in place of 32 bit DSNs on wire. For us, with 2 subflows at
524  * 512K each, sequence wraparound detection can be done by checking whether
525  * the 32-bit value obtained on wire is 2**31 bytes apart from the stored
526  * lower 32-bits of the Data Sequence Number. Bogus DSNs are dropped by
527  * comparing against rwnd. Bogus DSNs within rwnd cannot be protected against
528  * and are as weak as bogus TCP sequence numbers.
529  */
530 #define MPTCP_EXTEND_DSN(x, y, z) {                                     \
531 	if ((MPTCP_DATASEQ_LOW32(x) > y) &&                             \
532 	    ((((u_int32_t)MPTCP_DATASEQ_LOW32(x)) - (u_int32_t)y) >=    \
533 	    (u_int32_t)(1U << 31))) {                                    \
534 	/* \
535 	 * y wrapped around and x and y are 2**31 bytes  apart \
536 	 */                                                             \
537 	        z = MPTCP_DATASEQ_HIGH32(x) + 0x100000000;              \
538 	        z |= y;                                                 \
539 	} else if ((MPTCP_DATASEQ_LOW32(x) < y) &&                      \
540 	    (((u_int32_t)y -                                            \
541 	    ((u_int32_t)MPTCP_DATASEQ_LOW32(x))) >=                     \
542 	    (u_int32_t)(1U << 31))) {                                    \
543 	/* \
544 	 * x wrapped around and x and y are 2**31 apart \
545 	 */                                                             \
546 	        z = MPTCP_DATASEQ_HIGH32(x) - 0x100000000;              \
547 	        z |= y;                                                 \
548 	} else {                                                        \
549 	        z = MPTCP_DATASEQ_HIGH32(x) | y;                        \
550 	}                                                               \
551 }
552 
553 #define mptcplog(x, y, z)       do {                                    \
554 	if ((mptcp_dbg_area & y) && (mptcp_dbg_level & z))              \
555 	        log x;                                                  \
556 } while (0)
557 
558 extern int mptcp_enable;        /* Multipath TCP */
559 extern int mptcp_mpcap_retries; /* Multipath TCP retries */
560 extern int mptcp_join_retries;  /* Multipath TCP Join retries */
561 extern int mptcp_dss_csum;      /* Multipath DSS Option checksum */
562 extern int mptcp_fail_thresh;   /* Multipath failover thresh of retransmits */
563 extern int mptcp_subflow_keeptime; /* Multipath subflow TCP_KEEPALIVE opt */
564 extern uint32_t mptcp_dbg_level;        /* Multipath TCP debugging level */
565 extern uint32_t mptcp_dbg_area; /* Multipath TCP debugging area */
566 extern int mptcp_developer_mode;        /* Allow aggregation mode */
567 extern uint32_t mptcp_cellicon_refcount;
568 extern uint32_t mptcp_enable_v1;
569 
570 #define MPTCP_CELLICON_TOGGLE_RATE      (5 * TCP_RETRANSHZ) /* Only toggle every 5 seconds */
571 
572 extern int tcp_jack_rxmt;       /* Join ACK retransmission value in msecs */
573 
574 __BEGIN_DECLS
575 extern void mptcp_init(struct protosw *, struct domain *);
576 extern int mptcp_ctloutput(struct socket *, struct sockopt *);
577 extern int mptcp_session_create(struct mppcb *);
578 extern boolean_t mptcp_ok_to_create_subflows(struct mptcb *mp_tp);
579 extern void mptcp_check_subflows_and_add(struct mptses *mpte);
580 extern void mptcp_check_subflows_and_remove(struct mptses *mpte);
581 extern void mptcpstats_inc_switch(struct mptses *mpte, const struct mptsub *mpts);
582 extern void mptcpstats_update(struct mptcp_itf_stats *stats, const struct mptsub *mpts);
583 extern int mptcpstats_get_index_by_ifindex(struct mptcp_itf_stats *stats, u_short ifindex, boolean_t create);
584 extern struct mptses *mptcp_drop(struct mptses *mpte, struct mptcb *mp_tp, u_short errno);
585 extern struct mptses *mptcp_close(struct mptses *, struct mptcb *);
586 extern int mptcp_lock(struct socket *, int, void *);
587 extern int mptcp_unlock(struct socket *, int, void *);
588 extern lck_mtx_t *mptcp_getlock(struct socket *, int);
589 extern void mptcp_subflow_workloop(struct mptses *);
590 
591 extern void mptcp_sched_create_subflows(struct mptses *);
592 
593 extern void mptcp_finish_usrclosed(struct mptses *mpte);
594 extern struct mptopt *mptcp_sopt_alloc(zalloc_flags_t);
595 extern const char *mptcp_sopt2str(int, int);
596 extern void mptcp_sopt_free(struct mptopt *);
597 extern void mptcp_sopt_insert(struct mptses *, struct mptopt *);
598 extern void mptcp_sopt_remove(struct mptses *, struct mptopt *);
599 extern struct mptopt *mptcp_sopt_find(struct mptses *, struct sockopt *);
600 
601 extern int mptcp_subflow_add(struct mptses *, struct sockaddr *,
602     struct sockaddr *, uint32_t, sae_connid_t *);
603 extern void mptcp_subflow_del(struct mptses *, struct mptsub *);
604 
605 extern void mptcp_handle_input(struct socket *so);
606 #define MPTCP_SUBOUT_PROBING    0x01
607 extern int mptcp_subflow_output(struct mptses *mpte, struct mptsub *mpts, int flags);
608 extern void mptcp_clean_reinjectq(struct mptses *mpte);
609 extern void mptcp_subflow_shutdown(struct mptses *, struct mptsub *);
610 extern void mptcp_subflow_disconnect(struct mptses *, struct mptsub *);
611 extern int mptcp_subflow_sosetopt(struct mptses *, struct mptsub *,
612     struct mptopt *);
613 extern int mptcp_subflow_sogetopt(struct mptses *, struct socket *,
614     struct mptopt *);
615 
616 extern void mptcp_input(struct mptses *, struct mbuf *);
617 extern boolean_t mptcp_can_send_more(struct mptcb *mp_tp, boolean_t ignore_reinject);
618 extern int mptcp_output(struct mptses *);
619 extern void mptcp_close_fsm(struct mptcb *, uint32_t);
620 
621 extern void mptcp_hmac_sha1(mptcp_key_t, mptcp_key_t, u_int32_t, u_int32_t,
622     u_char*);
623 extern void mptcp_hmac_sha256(mptcp_key_t, mptcp_key_t, u_char*, uint16_t,
624     u_char*);
625 extern void mptcp_get_mpjoin_hmac(mptcp_addr_id, struct mptcb *, u_char *, uint8_t);
626 extern void mptcp_get_rands(mptcp_addr_id, struct mptcb *, u_int32_t *,
627     u_int32_t *);
628 extern void mptcp_set_raddr_rand(mptcp_addr_id, struct mptcb *, mptcp_addr_id,
629     u_int32_t);
630 extern int mptcp_init_remote_parms(struct mptcb *);
631 extern boolean_t mptcp_ok_to_keepalive(struct mptcb *);
632 extern void mptcp_insert_dsn(struct mppcb *, struct mbuf *);
633 extern void mptcp_output_getm_dsnmap32(struct socket *so, int off,
634     uint32_t *dsn, uint32_t *relseq,
635     uint16_t *data_len, uint16_t *dss_csum);
636 extern void mptcp_output_getm_dsnmap64(struct socket *so, int off,
637     uint64_t *dsn, uint32_t *relseq,
638     uint16_t *data_len, uint16_t *dss_csum);
639 extern void mptcp_output_getm_data_level_details(struct socket *so, int off,
640     uint16_t *data_len, uint16_t *dss_csum);
641 extern void mptcp_act_on_txfail(struct socket *);
642 extern struct mptsub *mptcp_get_subflow(struct mptses *mpte, struct mptsub **preferred);
643 extern int mptcp_get_map_for_dsn(struct socket *so, uint64_t dsn_fail, uint32_t *tcp_seq);
644 extern int32_t mptcp_adj_sendlen(struct socket *so, int32_t off);
645 extern void mptcp_sbrcv_grow(struct mptcb *mp_tp);
646 extern int32_t mptcp_sbspace(struct mptcb *);
647 extern void mptcp_notify_mpready(struct socket *);
648 extern void mptcp_notify_mpfail(struct socket *);
649 extern void mptcp_notify_close(struct socket *);
650 extern boolean_t mptcp_no_rto_spike(struct socket*);
651 extern int mptcp_set_notsent_lowat(struct mptses *mpte, int optval);
652 extern u_int32_t mptcp_get_notsent_lowat(struct mptses *mpte);
653 extern int mptcp_notsent_lowat_check(struct socket *so);
654 extern void mptcp_ask_symptoms(struct mptses *mpte);
655 extern void mptcp_control_register(void);
656 extern int mptcp_is_wifi_unusable_for_session(struct mptses *mpte);
657 extern boolean_t symptoms_is_wifi_lossy(void);
658 extern void mptcp_session_necp_cb(void *, int, uint32_t, uint32_t, bool *);
659 extern struct sockaddr *mptcp_get_session_dst(struct mptses *mpte,
660     boolean_t has_v6, boolean_t has_v4);
661 extern void mptcp_set_restrictions(struct socket *mp_so);
662 extern void mptcp_clear_cellicon(void);
663 extern void mptcp_unset_cellicon(struct mptses *mpte, struct mptsub *mpts, uint32_t val);
664 extern void mptcp_reset_rexmit_state(struct tcpcb *tp);
665 extern void mptcp_reset_keepalive(struct tcpcb *tp);
666 extern int mptcp_validate_csum(struct tcpcb *tp, struct mbuf *m, uint64_t dsn,
667     uint32_t sseq, uint16_t dlen, uint16_t csum, int dfin);
668 __END_DECLS
669 
670 #endif /* BSD_KERNEL_PRIVATE */
671 #ifdef PRIVATE
672 
673 typedef struct mptcp_flow {
674 	uint64_t                flow_len;
675 	uint64_t                flow_tcpci_offset;
676 	uint32_t                flow_flags;
677 	sae_connid_t            flow_cid;
678 	struct sockaddr_storage flow_src;
679 	struct sockaddr_storage flow_dst;
680 	uint32_t                flow_relseq;    /* last subflow rel seq# */
681 	int32_t                 flow_soerror;   /* subflow level error */
682 	uint32_t                flow_probecnt;  /* number of probes sent */
683 	conninfo_tcp_t          flow_ci;        /* must be the last field */
684 } mptcp_flow_t;
685 
686 typedef struct conninfo_mptcp {
687 	uint64_t        mptcpci_len;
688 	uint64_t        mptcpci_flow_offset;    /* offsetof first flow */
689 	uint64_t        mptcpci_nflows;         /* number of subflows */
690 	uint32_t        mptcpci_state;          /* MPTCP level state */
691 	uint32_t        mptcpci_mpte_flags;     /* Session flags */
692 	uint32_t        mptcpci_flags;          /* MPTCB flags */
693 	uint32_t        mptcpci_ltoken;         /* local token */
694 	uint32_t        mptcpci_rtoken;         /* remote token */
695 	uint32_t        mptcpci_notsent_lowat;  /* NOTSENT_LOWAT */
696 
697 	/* Send side */
698 	uint64_t        mptcpci_snduna;         /* DSN of last unacked byte */
699 	uint64_t        mptcpci_sndnxt;         /* DSN of next byte to send */
700 	uint64_t        mptcpci_sndmax;         /* DSN of max byte sent */
701 	uint64_t        mptcpci_lidsn;          /* Local IDSN */
702 	uint32_t        mptcpci_sndwnd;         /* Send window snapshot */
703 
704 	/* Receive side */
705 	uint64_t        mptcpci_rcvnxt;         /* Next expected DSN */
706 	uint64_t        mptcpci_rcvatmark;      /* Session level rcvnxt */
707 	uint64_t        mptcpci_ridsn;          /* Peer's IDSN */
708 	uint32_t        mptcpci_rcvwnd;         /* Receive window */
709 
710 	uint8_t         mptcpci_mpte_addrid;    /* last addr id */
711 
712 	mptcp_flow_t    mptcpci_flows[1];
713 } conninfo_mptcp_t;
714 
715 /* Use SymptomsD notifications of wifi and cell status in subflow selection */
716 #define MPTCP_KERN_CTL_NAME    "com.apple.network.advisory"
717 typedef struct symptoms_advisory {
718 	union {
719 		uint32_t        sa_nwk_status_int;
720 		struct {
721 			union {
722 #define SYMPTOMS_ADVISORY_NOCOMMENT     0x0000
723 #define SYMPTOMS_ADVISORY_USEAPP        0xFFFF /* Very ugly workaround to avoid breaking backwards compatibility - ToDo: Fix it in +1 */
724 				uint16_t        sa_nwk_status;
725 				struct {
726 #define SYMPTOMS_ADVISORY_WIFI_BAD     0x01
727 #define SYMPTOMS_ADVISORY_WIFI_OK      0x02
728 					uint8_t sa_wifi_status;
729 #define SYMPTOMS_ADVISORY_CELL_BAD     0x01
730 #define SYMPTOMS_ADVISORY_CELL_OK      0x02
731 					uint8_t sa_cell_status;
732 				};
733 			};
734 			uint16_t        sa_unused;
735 		};
736 	};
737 } symptoms_advisory_t;
738 
739 #define MPTCP_TARGET_BASED_RSSI_THRESHOLD -75
740 struct mptcp_symptoms_answer {
741 	struct symptoms_advisory advisory;
742 	uuid_t  uuid;
743 	int32_t rssi;
744 };
745 
746 struct mptcp_symptoms_ask_uuid {
747 	uint32_t        cmd;
748 #define MPTCP_SYMPTOMS_ASK_UUID         1
749 	uuid_t          uuid;
750 	uint32_t        priority;
751 #define MPTCP_SYMPTOMS_UNKNOWN          0
752 #define MPTCP_SYMPTOMS_BACKGROUND       1
753 #define MPTCP_SYMPTOMS_FOREGROUND       2
754 };
755 
756 struct kev_mptcp_data {
757 	int value;
758 };
759 
760 #endif /* PRIVATE */
761 #endif /* _NETINET_MPTCP_VAR_H_ */
762