xref: /xnu-8020.140.41/bsd/netinet/mptcp_var.h (revision 27b03b360a988dfd3dfdf34262bb0042026747cc)
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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 	thread_call_t   mpte_stop_urgency;
74 
75 	uint32_t        mpte_last_cellicon_set;
76 	uint32_t        mpte_cellicon_increments;
77 
78 	union {
79 		/* Source address of initial subflow */
80 		struct sockaddr _mpte_src;
81 		struct sockaddr_in _mpte_src_v4;
82 		struct sockaddr_in6 _mpte_src_v6;
83 	} mpte_u_src;
84 #define mpte_src mpte_u_src._mpte_src
85 #define __mpte_src_v4 mpte_u_src._mpte_src_v4
86 #define __mpte_src_v6 mpte_u_src._mpte_src_v6
87 	union {
88 		/* Destination address of initial subflow */
89 		struct sockaddr _mpte_dst;
90 		struct sockaddr_in _mpte_dst_v4;
91 		struct sockaddr_in6 _mpte_dst_v6;
92 	} mpte_u_dst;
93 #define mpte_dst mpte_u_dst._mpte_dst
94 #define __mpte_dst_v4 mpte_u_dst._mpte_dst_v4
95 #define __mpte_dst_v6 mpte_u_dst._mpte_dst_v6
96 
97 	struct sockaddr_in      mpte_sub_dst_v4;
98 	struct sockaddr_in6     mpte_sub_dst_v6;
99 	uint8_t         sub_dst_addr_id_v4;
100 	uint8_t         sub_dst_addr_id_v6;
101 
102 	uint16_t        mpte_alternate_port;    /* Alternate port for subflow establishment (network-byte-order) */
103 
104 	int mpte_epid;
105 	uuid_t mpte_euuid;
106 
107 	struct mptsub   *mpte_active_sub;       /* ptr to last active subf */
108 	uint16_t mpte_flags;                    /* per mptcp session flags */
109 #define MPTE_SND_REM_ADDR       0x01            /* Send Remove_addr option */
110 #define MPTE_SVCTYPE_CHECKED    0x02            /* Did entitlement-check for service-type */
111 #define MPTE_FIRSTPARTY         0x04            /* First-party app used multipath_extended entitlement */
112 #define MPTE_ACCESS_GRANTED     0x08            /* Access to cellular has been granted for this connection */
113 #define MPTE_FORCE_ENABLE       0x10            /* For MPTCP regardless of heuristics to detect middleboxes */
114 #define MPTE_IN_WORKLOOP        0x20            /* Are we currently inside the workloop ? */
115 #define MPTE_WORKLOOP_RELAUNCH  0x40            /* Another event got queued, we should restart the workloop */
116 #define MPTE_UNICAST_IP         0x80            /* New subflows are only being established towards the unicast IP in the ADD_ADDR */
117 #define MPTE_CELL_PROHIBITED    0x100           /* Cell access has been prohibited based on signal quality */
118 #define MPTE_FORCE_V0           0x200           /* Force MPTCP to use version 0 regradless of tcp cache */
119 #define MPTE_FORCE_V1           0x400           /* Force MPTCP to use version 1 regradless of tcp cache */
120 	uint8_t mpte_svctype;                   /* MPTCP Service type */
121 	uint8_t mpte_lost_aid;                  /* storing lost address id */
122 	uint8_t mpte_addrid_last;               /* storing address id parm */
123 
124 #define MPTE_ITFINFO_SIZE       4
125 	uint32_t        mpte_itfinfo_size;
126 	struct mpt_itf_info     _mpte_itfinfo[MPTE_ITFINFO_SIZE];
127 	struct mpt_itf_info     *mpte_itfinfo;
128 
129 	struct mbuf             *mpte_reinjectq;
130 
131 	/* The below is used for stats */
132 	uint32_t        mpte_subflow_switches;  /* Number of subflow-switches in sending */
133 	uint32_t        mpte_used_cell:1,
134 	    mpte_used_wifi:1,
135 	    mpte_initial_cell:1,
136 	    mpte_triggered_cell,
137 	    mpte_handshake_success:1,
138 	    mpte_last_added_addr_is_v4:1;
139 
140 	struct mptcp_itf_stats  mpte_itfstats[MPTCP_ITFSTATS_SIZE];
141 	uint64_t                mpte_init_txbytes __attribute__((aligned(8)));
142 	uint64_t                mpte_init_rxbytes __attribute__((aligned(8)));
143 };
144 
145 static inline struct socket *
mptetoso(struct mptses * mpte)146 mptetoso(struct mptses *mpte)
147 {
148 	return mpte->mpte_mppcb->mpp_socket;
149 }
150 
151 static inline struct mptses *
mptompte(struct mppcb * mp)152 mptompte(struct mppcb *mp)
153 {
154 	return (struct mptses *)mp->mpp_pcbe;
155 }
156 
157 static inline struct mptses *
mpsotompte(struct socket * so)158 mpsotompte(struct socket *so)
159 {
160 	return mptompte(mpsotomppcb(so));
161 }
162 
163 static inline boolean_t
mpp_try_lock(struct mppcb * mp)164 mpp_try_lock(struct mppcb *mp)
165 {
166 	if (!lck_mtx_try_lock(&mp->mpp_lock)) {
167 		return false;
168 	}
169 
170 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
171 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
172 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
173 
174 	return true;
175 }
176 
177 static inline void
mpp_lock(struct mppcb * mp)178 mpp_lock(struct mppcb *mp)
179 {
180 	lck_mtx_lock(&mp->mpp_lock);
181 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
182 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
183 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
184 }
185 
186 static inline void
mpp_unlock(struct mppcb * mp)187 mpp_unlock(struct mppcb *mp)
188 {
189 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
190 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
191 	VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
192 	lck_mtx_unlock(&mp->mpp_lock);
193 }
194 
195 static inline lck_mtx_t *
mpp_getlock(struct mppcb * mp,int flags)196 mpp_getlock(struct mppcb *mp, int flags)
197 {
198 	if (flags & PR_F_WILLUNLOCK) {
199 		VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
200 		VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
201 		VERIFY(!(mp->mpp_flags & MPP_INSIDE_SETGETOPT));
202 	}
203 
204 	return &mp->mpp_lock;
205 }
206 
207 static inline int
mptcp_subflow_cwnd_space(struct socket * so)208 mptcp_subflow_cwnd_space(struct socket *so)
209 {
210 	struct tcpcb *tp = sototcpcb(so);
211 	int cwnd = (int)(MIN(tp->snd_wnd, tp->snd_cwnd) - (so->so_snd.sb_cc));
212 
213 	return MIN(cwnd, sbspace(&so->so_snd));
214 }
215 
216 static inline bool
mptcp_subflows_need_backup_flag(struct mptses * mpte)217 mptcp_subflows_need_backup_flag(struct mptses *mpte)
218 {
219 	return mpte->mpte_svctype < MPTCP_SVCTYPE_AGGREGATE ||
220 	       mpte->mpte_svctype == MPTCP_SVCTYPE_PURE_HANDOVER;
221 }
222 
223 /*
224  * MPTCP socket options
225  */
226 struct mptopt {
227 	TAILQ_ENTRY(mptopt)     mpo_entry;      /* glue to other options */
228 	uint32_t                mpo_flags;      /* see flags below */
229 	int                     mpo_level;      /* sopt_level */
230 	int                     mpo_name;       /* sopt_name */
231 	int                     mpo_intval;     /* sopt_val */
232 };
233 
234 #define MPOF_ATTACHED           0x1     /* attached to MP socket */
235 #define MPOF_SUBFLOW_OK         0x2     /* can be issued on subflow socket */
236 #define MPOF_INTERIM            0x4     /* has not been issued on any subflow */
237 
238 /*
239  * MPTCP subflow
240  *
241  * Note that mpts_flags and mpts_evctl are modified via atomic operations.
242  */
243 struct mptsub {
244 	TAILQ_ENTRY(mptsub)   mpts_entry;     /* glue to peer subflows */
245 	uint32_t              mpts_refcnt;    /* reference count */
246 	uint32_t              mpts_flags;     /* see flags below */
247 	long                  mpts_evctl;     /* subflow control events */
248 	sae_connid_t          mpts_connid;    /* subflow connection ID */
249 	int                   mpts_oldintval; /* sopt_val before sosetopt  */
250 	struct mptses         *mpts_mpte;     /* back ptr to MPTCP session */
251 	struct socket         *mpts_socket;   /* subflow socket */
252 	struct sockaddr       *mpts_src;      /* source address */
253 
254 	union {
255 		/* destination address */
256 		struct sockaddr         _mpts_dst;
257 		struct sockaddr_in      _mpts_dst_v4;
258 		struct sockaddr_in6     _mpts_dst_v6;
259 	} mpts_u_dst;
260 #define mpts_dst mpts_u_dst._mpts_dst
261 #define __mpts_dst_v4 mpts_u_dst._mpts_dst_v4
262 #define __mpts_dst_v6 mpts_u_dst._mpts_dst_v6
263 	u_int32_t               mpts_rel_seq;   /* running count of subflow # */
264 	u_int32_t               mpts_iss;       /* Initial sequence number, taking TFO into account */
265 	u_int32_t               mpts_ifscope;   /* scoped to the interface */
266 	uint32_t                mpts_probesoon; /* send probe after probeto */
267 	uint32_t                mpts_probecnt;  /* number of probes sent */
268 	uint32_t                mpts_maxseg;    /* cached value of t_maxseg */
269 };
270 
271 /*
272  * Valid values for mpts_flags.  In particular:
273  *
274  *    - MP_CAPABLE means that the connection is successfully established as
275  *	MPTCP and data transfer may occur, but is not yet ready for multipath-
276  *	related semantics until MP_READY.  I.e. if this is on the first subflow,
277  *	it causes the MPTCP socket to transition to a connected state, except
278  *	that additional subflows will not be established; they will be marked
279  *	with PENDING and will be processed when the first subflow is marked
280  *	with MP_READY.
281  *
282  *    - MP_READY implies that an MP_CAPABLE connection has been confirmed as
283  *	an MPTCP connection.  See notes above.
284  *
285  *    - MP_DEGRADED implies that the connection has lost its MPTCP capabilities
286  *	but data transfer on the MPTCP socket is unaffected.  Any existing
287  *	PENDING subflows will be disconnected, and further attempts to connect
288  *	additional subflows will be rejected.
289  *
290  * Note that these are per-subflow flags.  The setting and clearing of MP_READY
291  * reflects the state of the MPTCP connection with regards to its multipath
292  * semantics, via the MPTCPF_JOIN_READY flag.  Until that flag is set (meaning
293  * until at least a subflow is marked with MP_READY), further connectx(2)
294  * attempts to join will be queued.  When the flag is cleared (after it has
295  * been set), further connectx(2) will fail (and existing queued ones will be
296  * aborted) and the MPTCP connection loses all of its multipath semantics.
297  *
298  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
299  */
300 #define MPTSF_ATTACHED          0x00000001      /* attached to MPTCP PCB */
301 #define MPTSF_CONNECTING        0x00000002      /* connection was attempted */
302 #define MPTSF_CONNECT_PENDING   0x00000004      /* will connect when MPTCP is ready */
303 #define MPTSF_CONNECTED         0x00000008      /* connection is established */
304 #define MPTSF_DISCONNECTING     0x00000010      /* disconnection was attempted */
305 #define MPTSF_DISCONNECTED      0x00000020      /* has been disconnected */
306 #define MPTSF_MP_CAPABLE        0x00000040      /* connected as a MPTCP subflow */
307 #define MPTSF_MP_READY          0x00000080      /* MPTCP has been confirmed */
308 #define MPTSF_MP_DEGRADED       0x00000100      /* has lost its MPTCP capabilities */
309 #define MPTSF_PREFERRED         0x00000200      /* primary/preferred subflow */
310 #define MPTSF_SOPT_OLDVAL       0x00000400      /* old option value is valid */
311 #define MPTSF_SOPT_INPROG       0x00000800      /* sosetopt in progress */
312 #define MPTSF_FAILINGOVER       0x00001000      /* subflow not used for output */
313 #define MPTSF_ACTIVE            0x00002000      /* subflow currently in use */
314 #define MPTSF_MPCAP_CTRSET      0x00004000      /* mpcap counter */
315 #define MPTSF_CLOSED            0x00008000      /* soclose_locked has been called on this subflow */
316 #define MPTSF_TFO_REQD          0x00010000      /* TFO requested */
317 #define MPTSF_CLOSE_REQD        0x00020000      /* A close has been requested from NECP */
318 #define MPTSF_INITIAL_SUB       0x00040000      /* This is the initial subflow */
319 #define MPTSF_READ_STALL        0x00080000      /* A read-stall has been detected */
320 #define MPTSF_WRITE_STALL       0x00100000      /* A write-stall has been detected */
321 #define MPTSF_FULLY_ESTABLISHED 0x00200000      /* Subflow is fully established and it has been confirmed
322 	                                         * whether or not it supports MPTCP.
323 	                                         * No need for further middlebox-detection.
324 	                                         */
325 #define MPTSF_CELLICON_SET      0x00400000      /* This subflow set the cellicon */
326 
327 #define MPTSF_BITS \
328 	"\020\1ATTACHED\2CONNECTING\3PENDING\4CONNECTED\5DISCONNECTING" \
329 	"\6DISCONNECTED\7MP_CAPABLE\10MP_READY\11MP_DEGRADED" \
330 	"\12PREFERRED\13SOPT_OLDVAL" \
331 	"\14SOPT_INPROG\15FAILINGOVER\16ACTIVE\17MPCAP_CTRSET" \
332 	"\20CLOSED\21TFO_REQD\22CLOSEREQD\23INITIALSUB\24READ_STALL" \
333 	"\25WRITE_STALL\26CONFIRMED"
334 
335 /*
336  * MPTCP states
337  * Keep in sync with bsd/dev/dtrace/mptcp.d
338  */
339 typedef enum mptcp_state {
340 	MPTCPS_CLOSED           = 0,    /* closed */
341 	MPTCPS_LISTEN           = 1,    /* not yet implemented */
342 	MPTCPS_ESTABLISHED      = 2,    /* MPTCP connection established */
343 	MPTCPS_CLOSE_WAIT       = 3,    /* rcvd DFIN, waiting for close */
344 	MPTCPS_FIN_WAIT_1       = 4,    /* have closed, sent DFIN */
345 	MPTCPS_CLOSING          = 5,    /* closed xchd DFIN, waiting DFIN ACK */
346 	MPTCPS_LAST_ACK         = 6,    /* had DFIN and close; await DFIN ACK */
347 	MPTCPS_FIN_WAIT_2       = 7,    /* have closed, DFIN is acked */
348 	MPTCPS_TIME_WAIT        = 8,    /* in 2*MSL quiet wait after close */
349 	MPTCPS_TERMINATE        = 9,    /* terminal state */
350 } mptcp_state_t;
351 
352 typedef u_int64_t       mptcp_key_t;
353 typedef u_int32_t       mptcp_token_t;
354 typedef u_int8_t        mptcp_addr_id;
355 
356 
357 /* Address ID list */
358 struct mptcp_subf_auth_entry {
359 	LIST_ENTRY(mptcp_subf_auth_entry) msae_next;
360 	u_int32_t       msae_laddr_rand;        /* Local nonce */
361 	u_int32_t       msae_raddr_rand;        /* Remote nonce */
362 	mptcp_addr_id   msae_laddr_id;          /* Local addr ID */
363 	mptcp_addr_id   msae_raddr_id;          /* Remote addr ID */
364 };
365 
366 /*
367  * MPTCP Protocol Control Block
368  *
369  * Protected by per-MPTCP mpt_lock.
370  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
371  */
372 struct mptcb {
373 	struct mptses  *mpt_mpte;               /* back ptr to MPTCP session */
374 	mptcp_state_t   mpt_state;              /* MPTCP state */
375 	uint32_t        mpt_flags;              /* see flags below */
376 	uint8_t         mpt_version;            /* MPTCP proto version */
377 	uint8_t         mpt_peer_version;       /* Version from peer */
378 	u_short         mpt_softerror;          /* error not yet reported */
379 	/*
380 	 * Authentication and metadata invariants
381 	 */
382 	mptcp_key_t     mpt_localkey;           /* in network byte order */
383 	mptcp_key_t     mpt_remotekey;          /* in network byte order */
384 	mptcp_token_t   mpt_localtoken;         /* HMAC SHA1 of local key */
385 	mptcp_token_t   mpt_remotetoken;        /* HMAC SHA1 of remote key */
386 
387 	/*
388 	 * Timer vars for scenarios where subflow level acks arrive, but
389 	 * Data ACKs do not.
390 	 */
391 	int             mpt_rxtshift;           /* num of consecutive retrans */
392 	uint64_t        mpt_rxtstart;           /* time at which rxt started */
393 	uint64_t        mpt_rtseq;              /* seq # being tracked */
394 	uint64_t        mpt_timewait;           /* timewait */
395 	uint32_t        mpt_timer_vals;         /* timer related values */
396 	/*
397 	 * Sending side
398 	 */
399 	uint64_t        mpt_snduna;             /* DSN of last unacked byte */
400 	uint64_t        mpt_sndnxt;             /* DSN of next byte to send */
401 	uint64_t        mpt_sndmax;             /* DSN of max byte sent */
402 	uint64_t        mpt_local_idsn;         /* First byte's DSN */
403 	uint32_t        mpt_sndwnd;
404 	uint64_t        mpt_sndwl1;
405 	uint64_t        mpt_sndwl2;
406 	/*
407 	 * Receiving side
408 	 */
409 	uint64_t        mpt_rcvnxt;             /* Next expected DSN */
410 	uint64_t        mpt_remote_idsn;        /* Peer's IDSN */
411 	uint64_t        mpt_rcvadv;
412 	uint32_t        mpt_rcvwnd;
413 	LIST_HEAD(, mptcp_subf_auth_entry) mpt_subauth_list; /* address IDs */
414 	/*
415 	 * Fastclose
416 	 */
417 	uint64_t        mpt_dsn_at_csum_fail;   /* MPFail Opt DSN */
418 	uint32_t        mpt_ssn_at_csum_fail;   /* MPFail Subflow Seq */
419 	/*
420 	 * Zombie handling
421 	 */
422 #define MPT_GC_TICKS            (30)
423 #define MPT_GC_TICKS_FAST       (10)
424 	int32_t         mpt_gc_ticks;           /* Used for zombie deletion */
425 
426 	uint32_t        mpt_notsent_lowat;      /* TCP_NOTSENT_LOWAT support */
427 
428 	struct tsegqe_head      mpt_segq;
429 	uint32_t        mpt_reassqlen;          /* length of reassembly queue */
430 };
431 
432 /* valid values for mpt_flags (see also notes on mpts_flags above) */
433 #define MPTCPF_CHECKSUM                 0x001   /* checksum DSS option */
434 #define MPTCPF_FALLBACK_TO_TCP          0x002   /* Fallback to TCP */
435 #define MPTCPF_JOIN_READY               0x004   /* Ready to start 2 or more subflows */
436 #define MPTCPF_RECVD_MPFAIL             0x008   /* Received MP_FAIL option */
437 #define MPTCPF_SND_64BITDSN             0x010   /* Send full 64-bit DSN */
438 #define MPTCPF_SND_64BITACK             0x020   /* Send 64-bit ACK response */
439 #define MPTCPF_RCVD_64BITACK            0x040   /* Received 64-bit Data ACK */
440 #define MPTCPF_POST_FALLBACK_SYNC       0x080   /* Post fallback resend data */
441 #define MPTCPF_FALLBACK_HEURISTIC       0x100   /* Send SYN without MP_CAPABLE due to heuristic */
442 #define MPTCPF_HEURISTIC_TRAC           0x200   /* Tracked this connection in the heuristics as a failure */
443 #define MPTCPF_REASS_INPROG             0x400   /* Reassembly is in progress */
444 #define MPTCPF_UNICAST_IP               0x800
445 
446 #define MPTCPF_BITS \
447 	"\020\1CHECKSUM\2FALLBACK_TO_TCP\3JOIN_READY\4RECVD_MPFAIL" \
448 	"\5SND_64BITDSN\6SND_64BITACK\7RCVD_64BITACK\10POST_FALLBACK_SYNC" \
449 	"\11FALLBACK_HEURISTIC\12HEURISTIC_TRAC\13REASS_INPROG"
450 
451 /* valid values for mpt_timer_vals */
452 #define MPTT_REXMT              0x01    /* Starting Retransmit Timer */
453 #define MPTT_TW                 0x02    /* Starting Timewait Timer */
454 #define MPTT_FASTCLOSE          0x04    /* Starting Fastclose wait timer */
455 
456 /* events for close FSM */
457 #define MPCE_CLOSE              0x1
458 #define MPCE_RECV_DATA_ACK      0x2
459 #define MPCE_RECV_DATA_FIN      0x4
460 
461 /* mptcb manipulation */
462 static inline struct mptcb *
tptomptp(struct tcpcb * tp)463 tptomptp(struct tcpcb *tp)
464 {
465 	return tp->t_mptcb;
466 }
467 
468 /*
469  * MPTCP control block and state structures are allocated along with
470  * the MP protocol control block; the folllowing represents the layout.
471  */
472 struct mpp_mtp {
473 	struct mppcb            mpp;            /* Multipath PCB */
474 	struct mptses           mpp_ses;        /* MPTCP session */
475 	struct mptcb            mtcb;           /* MPTCP PCB */
476 };
477 
478 #ifdef SYSCTL_DECL
479 SYSCTL_DECL(_net_inet_mptcp);
480 #endif /* SYSCTL_DECL */
481 
482 extern struct mppcbinfo mtcbinfo;
483 extern struct pr_usrreqs mptcp_usrreqs;
484 extern os_log_t mptcp_log_handle;
485 
486 /* Encryption algorithm related definitions */
487 #define HMAC_TRUNCATED_SYNACK          8
488 #define HMAC_TRUNCATED_ACK         20
489 #define HMAC_TRUNCATED_ADD_ADDR         8
490 
491 /* MPTCP Debugging Levels */
492 #define MPTCP_LOGLVL_NONE       0x0     /* No debug logging */
493 #define MPTCP_LOGLVL_ERR        0x1     /* Errors in execution are logged */
494 #define MPTCP_LOGLVL_LOG        0x2     /* Important logs */
495 #define MPTCP_LOGLVL_VERBOSE    0x4     /* Verbose logs */
496 
497 /* MPTCP sub-components for debug logging */
498 #define MPTCP_NO_DBG            0x00    /* No areas are logged */
499 #define MPTCP_STATE_DBG         0x01    /* State machine logging */
500 #define MPTCP_SOCKET_DBG        0x02    /* Socket call logging */
501 #define MPTCP_SENDER_DBG        0x04    /* Sender side logging */
502 #define MPTCP_RECEIVER_DBG      0x08    /* Receiver logging */
503 #define MPTCP_EVENTS_DBG        0x10    /* Subflow events logging */
504 
505 /* Mask to obtain 32-bit portion of data sequence number */
506 #define MPTCP_DATASEQ_LOW32_MASK        (0xffffffff)
507 #define MPTCP_DATASEQ_LOW32(seq)        (seq & MPTCP_DATASEQ_LOW32_MASK)
508 
509 /* Mask to obtain upper 32-bit portion of data sequence number */
510 #define MPTCP_DATASEQ_HIGH32_MASK       (0xffffffff00000000)
511 #define MPTCP_DATASEQ_HIGH32(seq)       (seq & MPTCP_DATASEQ_HIGH32_MASK)
512 
513 /* Mask to obtain 32-bit portion of data ack */
514 #define MPTCP_DATAACK_LOW32_MASK        (0xffffffff)
515 #define MPTCP_DATAACK_LOW32(ack)        (ack & MPTCP_DATAACK_LOW32_MASK)
516 
517 /* Mask to obtain upper 32-bit portion of data ack */
518 #define MPTCP_DATAACK_HIGH32_MASK       (0xffffffff00000000)
519 #define MPTCP_DATAACK_HIGH32(ack)       (ack & MPTCP_DATAACK_HIGH32_MASK)
520 
521 /*
522  * x is the 64-bit data sequence number, y the 32-bit data seq number to be
523  * extended. z is y extended to the appropriate 64-bit value.
524  * This algorithm is based on the fact that subflow level window sizes are
525  * at the maximum 2**30 (in reality, they are a lot lesser). A high throughput
526  * application sending on a large number of subflows can in theory have very
527  * large MPTCP level send and receive windows. In which case, 64 bit DSNs
528  * must be sent in place of 32 bit DSNs on wire. For us, with 2 subflows at
529  * 512K each, sequence wraparound detection can be done by checking whether
530  * the 32-bit value obtained on wire is 2**31 bytes apart from the stored
531  * lower 32-bits of the Data Sequence Number. Bogus DSNs are dropped by
532  * comparing against rwnd. Bogus DSNs within rwnd cannot be protected against
533  * and are as weak as bogus TCP sequence numbers.
534  */
535 #define MPTCP_EXTEND_DSN(x, y, z) {                                     \
536 	if ((MPTCP_DATASEQ_LOW32(x) > y) &&                             \
537 	    ((((u_int32_t)MPTCP_DATASEQ_LOW32(x)) - (u_int32_t)y) >=    \
538 	    (u_int32_t)(1U << 31))) {                                    \
539 	/* \
540 	 * y wrapped around and x and y are 2**31 bytes  apart \
541 	 */                                                             \
542 	        z = MPTCP_DATASEQ_HIGH32(x) + 0x100000000;              \
543 	        z |= y;                                                 \
544 	} else if ((MPTCP_DATASEQ_LOW32(x) < y) &&                      \
545 	    (((u_int32_t)y -                                            \
546 	    ((u_int32_t)MPTCP_DATASEQ_LOW32(x))) >=                     \
547 	    (u_int32_t)(1U << 31))) {                                    \
548 	/* \
549 	 * x wrapped around and x and y are 2**31 apart \
550 	 */                                                             \
551 	        z = MPTCP_DATASEQ_HIGH32(x) - 0x100000000;              \
552 	        z |= y;                                                 \
553 	} else {                                                        \
554 	        z = MPTCP_DATASEQ_HIGH32(x) | y;                        \
555 	}                                                               \
556 }
557 
558 #define mptcplog(x, y, z)       do {                                    \
559 	if ((mptcp_dbg_area & y) && (mptcp_dbg_level & z))              \
560 	        log x;                                                  \
561 } while (0)
562 
563 extern int mptcp_enable;        /* Multipath TCP */
564 extern int mptcp_mpcap_retries; /* Multipath TCP retries */
565 extern int mptcp_join_retries;  /* Multipath TCP Join retries */
566 extern int mptcp_dss_csum;      /* Multipath DSS Option checksum */
567 extern int mptcp_fail_thresh;   /* Multipath failover thresh of retransmits */
568 extern int mptcp_subflow_keeptime; /* Multipath subflow TCP_KEEPALIVE opt */
569 extern uint32_t mptcp_dbg_level;        /* Multipath TCP debugging level */
570 extern uint32_t mptcp_dbg_area; /* Multipath TCP debugging area */
571 extern int mptcp_developer_mode;        /* Allow aggregation mode */
572 extern uint32_t mptcp_cellicon_refcount;
573 extern uint32_t mptcp_enable_v1;
574 
575 #define MPTCP_CELLICON_TOGGLE_RATE      (5 * TCP_RETRANSHZ) /* Only toggle every 5 seconds */
576 
577 extern int tcp_jack_rxmt;       /* Join ACK retransmission value in msecs */
578 
579 extern int mptcp_reass_total_qlen;
580 
581 __BEGIN_DECLS
582 extern void mptcp_init(struct protosw *, struct domain *);
583 extern int mptcp_ctloutput(struct socket *, struct sockopt *);
584 extern int mptcp_session_create(struct mppcb *);
585 extern boolean_t mptcp_ok_to_create_subflows(struct mptcb *mp_tp);
586 extern void mptcp_check_subflows_and_add(struct mptses *mpte);
587 extern void mptcp_check_subflows_and_remove(struct mptses *mpte);
588 extern void mptcpstats_inc_switch(struct mptses *mpte, const struct mptsub *mpts);
589 extern void mptcpstats_update(struct mptcp_itf_stats *stats, const struct mptsub *mpts);
590 extern int mptcpstats_get_index_by_ifindex(struct mptcp_itf_stats *stats, u_short ifindex, boolean_t create);
591 extern struct mptses *mptcp_drop(struct mptses *mpte, struct mptcb *mp_tp, u_short errno);
592 extern struct mptses *mptcp_close(struct mptses *, struct mptcb *);
593 extern int mptcp_lock(struct socket *, int, void *);
594 extern int mptcp_unlock(struct socket *, int, void *);
595 extern lck_mtx_t *mptcp_getlock(struct socket *, int);
596 extern void mptcp_subflow_workloop(struct mptses *);
597 
598 extern void mptcp_sched_create_subflows(struct mptses *);
599 
600 extern void mptcp_finish_usrclosed(struct mptses *mpte);
601 extern struct mptopt *mptcp_sopt_alloc(zalloc_flags_t);
602 extern const char *mptcp_sopt2str(int, int);
603 extern void mptcp_sopt_free(struct mptopt *);
604 extern void mptcp_sopt_insert(struct mptses *, struct mptopt *);
605 extern void mptcp_sopt_remove(struct mptses *, struct mptopt *);
606 extern struct mptopt *mptcp_sopt_find(struct mptses *, struct sockopt *);
607 
608 extern int mptcp_subflow_add(struct mptses *, struct sockaddr *,
609     struct sockaddr *, uint32_t, sae_connid_t *);
610 extern void mptcp_subflow_del(struct mptses *, struct mptsub *);
611 
612 extern void mptcp_handle_input(struct socket *so);
613 #define MPTCP_SUBOUT_PROBING    0x01
614 extern int mptcp_subflow_output(struct mptses *mpte, struct mptsub *mpts, int flags);
615 extern void mptcp_clean_reinjectq(struct mptses *mpte);
616 extern void mptcp_subflow_shutdown(struct mptses *, struct mptsub *);
617 extern void mptcp_subflow_disconnect(struct mptses *, struct mptsub *);
618 extern int mptcp_subflow_sosetopt(struct mptses *, struct mptsub *,
619     struct mptopt *);
620 extern int mptcp_subflow_sogetopt(struct mptses *, struct socket *,
621     struct mptopt *);
622 
623 extern void mptcp_input(struct mptses *, struct mbuf *);
624 extern boolean_t mptcp_can_send_more(struct mptcb *mp_tp, boolean_t ignore_reinject);
625 extern int mptcp_output(struct mptses *);
626 extern void mptcp_close_fsm(struct mptcb *, uint32_t);
627 
628 extern void mptcp_hmac_sha1(mptcp_key_t, mptcp_key_t, u_int32_t, u_int32_t,
629     u_char*);
630 extern void mptcp_hmac_sha256(mptcp_key_t, mptcp_key_t, u_char*, uint16_t,
631     u_char*);
632 extern void mptcp_get_mpjoin_hmac(mptcp_addr_id, struct mptcb *, u_char *, uint8_t);
633 extern void mptcp_get_rands(mptcp_addr_id, struct mptcb *, u_int32_t *,
634     u_int32_t *);
635 extern void mptcp_set_raddr_rand(mptcp_addr_id, struct mptcb *, mptcp_addr_id,
636     u_int32_t);
637 extern int mptcp_init_remote_parms(struct mptcb *);
638 extern boolean_t mptcp_ok_to_keepalive(struct mptcb *);
639 extern void mptcp_insert_dsn(struct mppcb *, struct mbuf *);
640 extern void mptcp_output_getm_dsnmap32(struct socket *so, int off,
641     uint32_t *dsn, uint32_t *relseq,
642     uint16_t *data_len, uint16_t *dss_csum);
643 extern void mptcp_output_getm_dsnmap64(struct socket *so, int off,
644     uint64_t *dsn, uint32_t *relseq,
645     uint16_t *data_len, uint16_t *dss_csum);
646 extern void mptcp_output_getm_data_level_details(struct socket *so, int off,
647     uint16_t *data_len, uint16_t *dss_csum);
648 extern void mptcp_act_on_txfail(struct socket *);
649 extern struct mptsub *mptcp_get_subflow(struct mptses *mpte, struct mptsub **preferred);
650 extern int mptcp_get_map_for_dsn(struct socket *so, uint64_t dsn_fail, uint32_t *tcp_seq);
651 extern int32_t mptcp_adj_sendlen(struct socket *so, int32_t off);
652 extern void mptcp_sbrcv_grow(struct mptcb *mp_tp);
653 extern int32_t mptcp_sbspace(struct mptcb *);
654 extern void mptcp_notify_mpready(struct socket *);
655 extern void mptcp_notify_mpfail(struct socket *);
656 extern void mptcp_notify_close(struct socket *);
657 extern boolean_t mptcp_no_rto_spike(struct socket*);
658 extern int mptcp_set_notsent_lowat(struct mptses *mpte, int optval);
659 extern u_int32_t mptcp_get_notsent_lowat(struct mptses *mpte);
660 extern int mptcp_notsent_lowat_check(struct socket *so);
661 extern void mptcp_ask_symptoms(struct mptses *mpte);
662 extern void mptcp_control_register(void);
663 extern int mptcp_is_wifi_unusable_for_session(struct mptses *mpte);
664 extern boolean_t symptoms_is_wifi_lossy(void);
665 extern void mptcp_session_necp_cb(void *, int, uint32_t, uint32_t, bool *);
666 extern struct sockaddr *mptcp_get_session_dst(struct mptses *mpte,
667     boolean_t has_v6, boolean_t has_v4);
668 extern void mptcp_set_restrictions(struct socket *mp_so);
669 extern void mptcp_clear_cellicon(void);
670 extern void mptcp_unset_cellicon(struct mptses *mpte, struct mptsub *mpts, uint32_t val);
671 extern void mptcp_reset_rexmit_state(struct tcpcb *tp);
672 extern void mptcp_reset_keepalive(struct tcpcb *tp);
673 extern int mptcp_validate_csum(struct tcpcb *tp, struct mbuf *m, uint64_t dsn,
674     uint32_t sseq, uint16_t dlen, uint16_t csum, int dfin);
675 __END_DECLS
676 
677 #endif /* BSD_KERNEL_PRIVATE */
678 #ifdef PRIVATE
679 
680 typedef struct mptcp_flow {
681 	uint64_t                flow_len;
682 	uint64_t                flow_tcpci_offset;
683 	uint32_t                flow_flags;
684 	sae_connid_t            flow_cid;
685 	struct sockaddr_storage flow_src;
686 	struct sockaddr_storage flow_dst;
687 	uint32_t                flow_relseq;    /* last subflow rel seq# */
688 	int32_t                 flow_soerror;   /* subflow level error */
689 	uint32_t                flow_probecnt;  /* number of probes sent */
690 	conninfo_tcp_t          flow_ci;        /* must be the last field */
691 } mptcp_flow_t;
692 
693 typedef struct conninfo_mptcp {
694 	uint64_t        mptcpci_len;
695 	uint64_t        mptcpci_flow_offset;    /* offsetof first flow */
696 	uint64_t        mptcpci_nflows;         /* number of subflows */
697 	uint32_t        mptcpci_state;          /* MPTCP level state */
698 	uint32_t        mptcpci_mpte_flags;     /* Session flags */
699 	uint32_t        mptcpci_flags;          /* MPTCB flags */
700 	uint32_t        mptcpci_ltoken;         /* local token */
701 	uint32_t        mptcpci_rtoken;         /* remote token */
702 	uint32_t        mptcpci_notsent_lowat;  /* NOTSENT_LOWAT */
703 
704 	/* Send side */
705 	uint64_t        mptcpci_snduna;         /* DSN of last unacked byte */
706 	uint64_t        mptcpci_sndnxt;         /* DSN of next byte to send */
707 	uint64_t        mptcpci_sndmax;         /* DSN of max byte sent */
708 	uint64_t        mptcpci_lidsn;          /* Local IDSN */
709 	uint32_t        mptcpci_sndwnd;         /* Send window snapshot */
710 
711 	/* Receive side */
712 	uint64_t        mptcpci_rcvnxt;         /* Next expected DSN */
713 	uint64_t        mptcpci_rcvatmark;      /* Session level rcvnxt */
714 	uint64_t        mptcpci_ridsn;          /* Peer's IDSN */
715 	uint32_t        mptcpci_rcvwnd;         /* Receive window */
716 
717 	uint8_t         mptcpci_mpte_addrid;    /* last addr id */
718 
719 	mptcp_flow_t    mptcpci_flows[1];
720 } conninfo_mptcp_t;
721 
722 /* Use SymptomsD notifications of wifi and cell status in subflow selection */
723 #define MPTCP_KERN_CTL_NAME    "com.apple.network.advisory"
724 typedef struct symptoms_advisory {
725 	union {
726 		uint32_t        sa_nwk_status_int;
727 		struct {
728 			union {
729 #define SYMPTOMS_ADVISORY_NOCOMMENT     0x0000
730 #define SYMPTOMS_ADVISORY_USEAPP        0xFFFF /* Very ugly workaround to avoid breaking backwards compatibility - ToDo: Fix it in +1 */
731 				uint16_t        sa_nwk_status;
732 				struct {
733 #define SYMPTOMS_ADVISORY_WIFI_BAD     0x01
734 #define SYMPTOMS_ADVISORY_WIFI_OK      0x02
735 					uint8_t sa_wifi_status;
736 #define SYMPTOMS_ADVISORY_CELL_BAD     0x01
737 #define SYMPTOMS_ADVISORY_CELL_OK      0x02
738 					uint8_t sa_cell_status;
739 				};
740 			};
741 			uint16_t        sa_unused;
742 		};
743 	};
744 } symptoms_advisory_t;
745 
746 #define MPTCP_TARGET_BASED_RSSI_THRESHOLD -75
747 struct mptcp_symptoms_answer {
748 	struct symptoms_advisory advisory;
749 	uuid_t  uuid;
750 	int32_t rssi;
751 };
752 
753 struct mptcp_symptoms_ask_uuid {
754 	uint32_t        cmd;
755 #define MPTCP_SYMPTOMS_ASK_UUID         1
756 	uuid_t          uuid;
757 	uint32_t        priority;
758 #define MPTCP_SYMPTOMS_UNKNOWN          0
759 #define MPTCP_SYMPTOMS_BACKGROUND       1
760 #define MPTCP_SYMPTOMS_FOREGROUND       2
761 };
762 
763 struct kev_mptcp_data {
764 	int value;
765 };
766 
767 #endif /* PRIVATE */
768 #endif /* _NETINET_MPTCP_VAR_H_ */
769