bsd/netinet/mptcp_var.h

   1 /*
   2  * Copyright (c) 2012-2017 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  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         uint16_t        mpte_numflows;          /* # of subflows in list */
  66         uint16_t        mpte_nummpcapflows;     /* # of MP_CAP subflows */
  67         sae_associd_t   mpte_associd;           /* MPTCP association ID */
  68         sae_connid_t    mpte_connid_last;       /* last used connection ID */
  69
  70         union {
  71                 /* Source address of initial subflow */
  72                 struct sockaddr mpte_src;
  73                 struct sockaddr_in __mpte_src_v4;
  74                 struct sockaddr_in6 __mpte_src_v6;
  75         };
  76
  77         union {
  78                 /* Destination address of initial subflow */
  79                 struct sockaddr mpte_dst;
  80                 struct sockaddr_in __mpte_dst_v4;
  81                 struct sockaddr_in6 __mpte_dst_v6;
  82         };
  83
  84         struct sockaddr_in mpte_dst_v4_nat64;
  85
  86         uint16_t        mpte_alternate_port;    /* Alternate port for subflow establishment (network-byte-order) */
  87
  88         struct mptsub   *mpte_active_sub;       /* ptr to last active subf */
  89         uint8_t mpte_flags;                     /* per mptcp session flags */
  90 #define MPTE_SND_REM_ADDR       0x01            /* Send Remove_addr option */
  91 #define MPTE_SVCTYPE_CHECKED    0x02            /* Did entitlement-check for service-type */
  92 #define MPTE_FIRSTPARTY         0x04            /* First-party app used multipath_extended entitlement */
  93 #define MPTE_ACCESS_GRANTED     0x08            /* Access to cellular has been granted for this connection */
  94         uint8_t mpte_svctype;                   /* MPTCP Service type */
  95         uint8_t mpte_lost_aid;                  /* storing lost address id */
  96         uint8_t mpte_addrid_last;               /* storing address id parm */
  97
  98 #define MPTE_ITFINFO_SIZE       4
  99         uint32_t        mpte_itfinfo_size;
 100         struct mpt_itf_info     _mpte_itfinfo[MPTE_ITFINFO_SIZE];
 101         struct mpt_itf_info     *mpte_itfinfo;
 102
 103         struct mbuf             *mpte_reinjectq;
 104
 105         /* The below is used for stats */
 106         uint32_t        mpte_subflow_switches;  /* Number of subflow-switches in sending */
 107         uint32_t        mpte_used_cell:1,
 108                         mpte_used_wifi:1,
 109                         mpte_initial_cell:1,
 110                         mpte_triggered_cell,
 111                         mpte_handshake_success:1;
 112
 113         struct mptcp_itf_stats  mpte_itfstats[MPTCP_ITFSTATS_SIZE];
 114         uint64_t                mpte_init_txbytes __attribute__((aligned(8)));
 115         uint64_t                mpte_init_rxbytes __attribute__((aligned(8)));
 116 };
 117
 118 static inline struct socket *
 119 mptetoso(struct mptses *mpte)
 120 {
 121         return (mpte->mpte_mppcb->mpp_socket);
 122 }
 123
 124 static inline struct mptses *
 125 mptompte(struct mppcb *mp)
 126 {
 127         return ((struct mptses *)mp->mpp_pcbe);
 128 }
 129
 130 static inline struct mptses *
 131 mpsotompte(struct socket *so)
 132 {
 133         return (mptompte(mpsotomppcb(so)));
 134 }
 135
 136 static inline void
 137 mpp_lock_assert_held(struct mppcb *mp)
 138 {
 139 #if !MACH_ASSERT
 140 #pragma unused(mp)
 141 #endif
 142         LCK_MTX_ASSERT(&mp->mpp_lock, LCK_MTX_ASSERT_OWNED);
 143 }
 144
 145 static inline void
 146 mpp_lock_assert_notheld(struct mppcb *mp)
 147 {
 148 #if !MACH_ASSERT
 149 #pragma unused(mp)
 150 #endif
 151         LCK_MTX_ASSERT(&mp->mpp_lock, LCK_MTX_ASSERT_NOTOWNED);
 152 }
 153
 154 static inline boolean_t
 155 mpp_try_lock(struct mppcb *mp)
 156 {
 157         if (!lck_mtx_try_lock(&mp->mpp_lock))
 158                 return false;
 159
 160         VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 161         VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 162
 163         return true;
 164 }
 165
 166 static inline void
 167 mpp_lock(struct mppcb *mp)
 168 {
 169         lck_mtx_lock(&mp->mpp_lock);
 170         VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 171         VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 172 }
 173
 174 static inline void
 175 mpp_unlock(struct mppcb *mp)
 176 {
 177         VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 178         VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 179         lck_mtx_unlock(&mp->mpp_lock);
 180 }
 181
 182 static inline lck_mtx_t *
 183 mpp_getlock(struct mppcb *mp, int flags)
 184 {
 185         if (flags & PR_F_WILLUNLOCK) {
 186                 VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 187                 VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 188         }
 189
 190         return (&mp->mpp_lock);
 191 }
 192
 193 static inline void
 194 mpte_lock_assert_held(struct mptses *mpte)
 195 {
 196         mpp_lock_assert_held(mpte->mpte_mppcb);
 197 }
 198
 199 static inline void
 200 mpte_lock_assert_notheld(struct mptses *mpte)
 201 {
 202         mpp_lock_assert_notheld(mpte->mpte_mppcb);
 203 }
 204
 205 static inline boolean_t
 206 mpte_try_lock(struct mptses *mpte)
 207 {
 208         return (mpp_try_lock(mpte->mpte_mppcb));
 209 }
 210
 211 static inline void
 212 mpte_lock(struct mptses *mpte)
 213 {
 214         mpp_lock(mpte->mpte_mppcb);
 215 }
 216
 217 static inline void
 218 mpte_unlock(struct mptses *mpte)
 219 {
 220         mpp_unlock(mpte->mpte_mppcb);
 221 }
 222
 223 static inline lck_mtx_t *
 224 mpte_getlock(struct mptses *mpte, int flags)
 225 {
 226         return mpp_getlock(mpte->mpte_mppcb, flags);
 227 }
 228
 229 static inline int
 230 mptcp_subflow_cwnd_space(struct socket *so)
 231 {
 232         struct tcpcb *tp = sototcpcb(so);
 233         int cwnd = min(tp->snd_wnd, tp->snd_cwnd) - (so->so_snd.sb_cc);
 234
 235         return (min(cwnd, sbspace(&so->so_snd)));
 236 }
 237
 238
 239 /*
 240  * MPTCP socket options
 241  */
 242 struct mptopt {
 243         TAILQ_ENTRY(mptopt)     mpo_entry;      /* glue to other options */
 244         uint32_t                mpo_flags;      /* see flags below */
 245         int                     mpo_level;      /* sopt_level */
 246         int                     mpo_name;       /* sopt_name */
 247         int                     mpo_intval;     /* sopt_val */
 248 };
 249
 250 #define MPOF_ATTACHED           0x1     /* attached to MP socket */
 251 #define MPOF_SUBFLOW_OK         0x2     /* can be issued on subflow socket */
 252 #define MPOF_INTERIM            0x4     /* has not been issued on any subflow */
 253
 254 /*
 255  * MPTCP subflow
 256  *
 257  * Note that mpts_flags and mpts_evctl are modified via atomic operations.
 258  */
 259 struct mptsub {
 260         TAILQ_ENTRY(mptsub)     mpts_entry;     /* glue to peer subflows */
 261         uint32_t                mpts_refcnt;    /* reference count */
 262         uint32_t                mpts_flags;     /* see flags below */
 263         uint32_t                mpts_evctl;     /* subflow control events */
 264         sae_connid_t            mpts_connid;    /* subflow connection ID */
 265         int                     mpts_oldintval; /* sopt_val before sosetopt  */
 266         struct mptses           *mpts_mpte;     /* back ptr to MPTCP session */
 267         struct socket           *mpts_socket;   /* subflow socket */
 268         struct sockaddr         *mpts_src;      /* source address */
 269
 270         union {
 271                 /* destination address */
 272                 struct sockaddr         mpts_dst;
 273                 struct sockaddr_in      __mpts_dst_v4;
 274                 struct sockaddr_in6     __mpts_dst_v6;
 275         };
 276
 277         u_int32_t               mpts_rel_seq;   /* running count of subflow # */
 278         u_int32_t               mpts_iss;       /* Initial sequence number, taking TFO into account */
 279         u_int32_t               mpts_ifscope;   /* scoped to the interface */
 280         uint32_t                mpts_probesoon; /* send probe after probeto */
 281         uint32_t                mpts_probecnt;  /* number of probes sent */
 282         uint32_t                mpts_maxseg;    /* cached value of t_maxseg */
 283 };
 284
 285 /*
 286  * Valid values for mpts_flags.  In particular:
 287  *
 288  *    - MP_CAPABLE means that the connection is successfully established as
 289  *      MPTCP and data transfer may occur, but is not yet ready for multipath-
 290  *      related semantics until MP_READY.  I.e. if this is on the first subflow,
 291  *      it causes the MPTCP socket to transition to a connected state, except
 292  *      that additional subflows will not be established; they will be marked
 293  *      with PENDING and will be processed when the first subflow is marked
 294  *      with MP_READY.
 295  *
 296  *    - MP_READY implies that an MP_CAPABLE connection has been confirmed as
 297  *      an MPTCP connection.  See notes above.
 298  *
 299  *    - MP_DEGRADED implies that the connection has lost its MPTCP capabilities
 300  *      but data transfer on the MPTCP socket is unaffected.  Any existing
 301  *      PENDING subflows will be disconnected, and further attempts to connect
 302  *      additional subflows will be rejected.
 303  *
 304  * Note that these are per-subflow flags.  The setting and clearing of MP_READY
 305  * reflects the state of the MPTCP connection with regards to its multipath
 306  * semantics, via the MPTCPF_JOIN_READY flag.  Until that flag is set (meaning
 307  * until at least a subflow is marked with MP_READY), further connectx(2)
 308  * attempts to join will be queued.  When the flag is cleared (after it has
 309  * been set), further connectx(2) will fail (and existing queued ones will be
 310  * aborted) and the MPTCP connection loses all of its multipath semantics.
 311  *
 312  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 313  */
 314 #define MPTSF_ATTACHED          0x00000001      /* attached to MPTCP PCB */
 315 #define MPTSF_CONNECTING        0x00000002      /* connection was attempted */
 316 #define MPTSF_CONNECT_PENDING   0x00000004      /* will connect when MPTCP is ready */
 317 #define MPTSF_CONNECTED         0x00000008      /* connection is established */
 318 #define MPTSF_DISCONNECTING     0x00000010      /* disconnection was attempted */
 319 #define MPTSF_DISCONNECTED      0x00000020      /* has been disconnected */
 320 #define MPTSF_MP_CAPABLE        0x00000040      /* connected as a MPTCP subflow */
 321 #define MPTSF_MP_READY          0x00000080      /* MPTCP has been confirmed */
 322 #define MPTSF_MP_DEGRADED       0x00000100      /* has lost its MPTCP capabilities */
 323 #define MPTSF_PREFERRED         0x00000200      /* primary/preferred subflow */
 324 #define MPTSF_SOPT_OLDVAL       0x00000400      /* old option value is valid */
 325 #define MPTSF_SOPT_INPROG       0x00000800      /* sosetopt in progress */
 326 #define MPTSF_FAILINGOVER       0x00001000      /* subflow not used for output */
 327 #define MPTSF_ACTIVE            0x00002000      /* subflow currently in use */
 328 #define MPTSF_MPCAP_CTRSET      0x00004000      /* mpcap counter */
 329 #define MPTSF_CLOSED            0x00008000      /* soclose_locked has been called on this subflow */
 330 #define MPTSF_TFO_REQD          0x00010000      /* TFO requested */
 331 #define MPTSF_CLOSE_REQD        0x00020000      /* A close has been requested from NECP */
 332 #define MPTSF_INITIAL_SUB       0x00040000      /* This is the initial subflow */
 333 #define MPTSF_READ_STALL        0x00080000      /* A read-stall has been detected */
 334 #define MPTSF_WRITE_STALL       0x00100000      /* A write-stall has been detected */
 335 #define MPTSF_CONFIRMED         0x00200000      /* Subflow confirmed to be MPTCP-capable */
 336
 337 #define MPTSF_BITS \
 338         "\020\1ATTACHED\2CONNECTING\3PENDING\4CONNECTED\5DISCONNECTING" \
 339         "\6DISCONNECTED\7MP_CAPABLE\10MP_READY\11MP_DEGRADED" \
 340         "\12PREFERRED\13SOPT_OLDVAL" \
 341         "\14SOPT_INPROG\15FAILINGOVER\16ACTIVE\17MPCAP_CTRSET" \
 342         "\20CLOSED\21TFO_REQD\22CLOSEREQD\23INITIALSUB\24READ_STALL" \
 343         "\25WRITE_STALL\26CONFIRMED"
 344
 345 /*
 346  * MPTCP states
 347  * Keep in sync with bsd/dev/dtrace/mptcp.d
 348  */
 349 typedef enum mptcp_state {
 350         MPTCPS_CLOSED           = 0,    /* closed */
 351         MPTCPS_LISTEN           = 1,    /* not yet implemented */
 352         MPTCPS_ESTABLISHED      = 2,    /* MPTCP connection established */
 353         MPTCPS_CLOSE_WAIT       = 3,    /* rcvd DFIN, waiting for close */
 354         MPTCPS_FIN_WAIT_1       = 4,    /* have closed, sent DFIN */
 355         MPTCPS_CLOSING          = 5,    /* closed xchd DFIN, waiting DFIN ACK */
 356         MPTCPS_LAST_ACK         = 6,    /* had DFIN and close; await DFIN ACK */
 357         MPTCPS_FIN_WAIT_2       = 7,    /* have closed, DFIN is acked */
 358         MPTCPS_TIME_WAIT        = 8,    /* in 2*MSL quiet wait after close */
 359         MPTCPS_TERMINATE        = 9,    /* terminal state */
 360 } mptcp_state_t;
 361
 362 typedef u_int64_t       mptcp_key_t;
 363 typedef u_int32_t       mptcp_token_t;
 364 typedef u_int8_t        mptcp_addr_id;
 365
 366
 367 /* Address ID list */
 368 struct mptcp_subf_auth_entry {
 369         LIST_ENTRY(mptcp_subf_auth_entry) msae_next;
 370         u_int32_t       msae_laddr_rand;        /* Local nonce */
 371         u_int32_t       msae_raddr_rand;        /* Remote nonce */
 372         mptcp_addr_id   msae_laddr_id;          /* Local addr ID */
 373         mptcp_addr_id   msae_raddr_id;          /* Remote addr ID */
 374 };
 375
 376 /*
 377  * MPTCP Protocol Control Block
 378  *
 379  * Protected by per-MPTCP mpt_lock.
 380  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 381  */
 382 struct mptcb {
 383         struct mptses   *mpt_mpte;              /* back ptr to MPTCP session */
 384         mptcp_state_t   mpt_state;              /* MPTCP state */
 385         u_int32_t       mpt_flags;              /* see flags below */
 386         u_int32_t       mpt_version;            /* MPTCP proto version */
 387         int             mpt_softerror;          /* error not yet reported */
 388         /*
 389          * Authentication and metadata invariants
 390          */
 391         mptcp_key_t     mpt_localkey;           /* in network byte order */
 392         mptcp_key_t     mpt_remotekey;          /* in network byte order */
 393         mptcp_token_t   mpt_localtoken;         /* HMAC SHA1 of local key */
 394         mptcp_token_t   mpt_remotetoken;        /* HMAC SHA1 of remote key */
 395
 396         /*
 397          * Timer vars for scenarios where subflow level acks arrive, but
 398          * Data ACKs do not.
 399          */
 400         int             mpt_rxtshift;           /* num of consecutive retrans */
 401         u_int32_t       mpt_rxtstart;           /* time at which rxt started */
 402         u_int64_t       mpt_rtseq;              /* seq # being tracked */
 403         u_int32_t       mpt_timer_vals;         /* timer related values */
 404         u_int32_t       mpt_timewait;           /* timewait */
 405         /*
 406          * Sending side
 407          */
 408         u_int64_t       mpt_snduna;             /* DSN of last unacked byte */
 409         u_int64_t       mpt_sndnxt;             /* DSN of next byte to send */
 410         u_int64_t       mpt_sndmax;             /* DSN of max byte sent */
 411         u_int64_t       mpt_local_idsn;         /* First byte's DSN */
 412         u_int32_t       mpt_sndwnd;
 413         u_int64_t       mpt_sndwl1;
 414         u_int64_t       mpt_sndwl2;
 415         /*
 416          * Receiving side
 417          */
 418         u_int64_t       mpt_rcvnxt;             /* Next expected DSN */
 419         u_int64_t       mpt_remote_idsn;        /* Peer's IDSN */
 420         u_int32_t       mpt_rcvwnd;
 421         LIST_HEAD(, mptcp_subf_auth_entry) mpt_subauth_list; /* address IDs */
 422         /*
 423          * Fastclose
 424          */
 425         u_int64_t       mpt_dsn_at_csum_fail;   /* MPFail Opt DSN */
 426         u_int32_t       mpt_ssn_at_csum_fail;   /* MPFail Subflow Seq */
 427         /*
 428          * Zombie handling
 429          */
 430 #define MPT_GC_TICKS            (30)
 431 #define MPT_GC_TICKS_FAST       (10)
 432         int32_t         mpt_gc_ticks;           /* Used for zombie deletion */
 433
 434         u_int32_t       mpt_notsent_lowat;      /* TCP_NOTSENT_LOWAT support */
 435         u_int32_t       mpt_peer_version;       /* Version from peer */
 436
 437         struct tsegqe_head      mpt_segq;
 438         u_int16_t       mpt_reassqlen;          /* length of reassembly queue */
 439 };
 440
 441 /* valid values for mpt_flags (see also notes on mpts_flags above) */
 442 #define MPTCPF_CHECKSUM                 0x001   /* checksum DSS option */
 443 #define MPTCPF_FALLBACK_TO_TCP          0x002   /* Fallback to TCP */
 444 #define MPTCPF_JOIN_READY               0x004   /* Ready to start 2 or more subflows */
 445 #define MPTCPF_RECVD_MPFAIL             0x008   /* Received MP_FAIL option */
 446 #define MPTCPF_SND_64BITDSN             0x010   /* Send full 64-bit DSN */
 447 #define MPTCPF_SND_64BITACK             0x020   /* Send 64-bit ACK response */
 448 #define MPTCPF_RCVD_64BITACK            0x040   /* Received 64-bit Data ACK */
 449 #define MPTCPF_POST_FALLBACK_SYNC       0x080   /* Post fallback resend data */
 450 #define MPTCPF_FALLBACK_HEURISTIC       0x100   /* Send SYN without MP_CAPABLE due to heuristic */
 451 #define MPTCPF_HEURISTIC_TRAC           0x200   /* Tracked this connection in the heuristics as a failure */
 452 #define MPTCPF_REASS_INPROG             0x400   /* Reassembly is in progress */
 453
 454 #define MPTCPF_BITS \
 455         "\020\1CHECKSUM\2FALLBACK_TO_TCP\3JOIN_READY\4RECVD_MPFAIL" \
 456         "\5SND_64BITDSN\6SND_64BITACK\7RCVD_64BITACK\10POST_FALLBACK_SYNC" \
 457         "\11FALLBACK_HEURISTIC\12HEURISTIC_TRAC\13REASS_INPROG"
 458
 459 /* valid values for mpt_timer_vals */
 460 #define MPTT_REXMT              0x01    /* Starting Retransmit Timer */
 461 #define MPTT_TW                 0x02    /* Starting Timewait Timer */
 462 #define MPTT_FASTCLOSE          0x04    /* Starting Fastclose wait timer */
 463
 464 /* events for close FSM */
 465 #define MPCE_CLOSE              0x1
 466 #define MPCE_RECV_DATA_ACK      0x2
 467 #define MPCE_RECV_DATA_FIN      0x4
 468
 469 /* mptcb manipulation */
 470 static inline struct mptcb *tptomptp(struct tcpcb *tp)
 471 {
 472         return (tp->t_mptcb);
 473 }
 474
 475 /*
 476  * MPTCP control block and state structures are allocated along with
 477  * the MP protocol control block; the folllowing represents the layout.
 478  */
 479 struct mpp_mtp {
 480         struct mppcb            mpp;            /* Multipath PCB */
 481         struct mptses           mpp_ses;        /* MPTCP session */
 482         struct mptcb            mtcb;           /* MPTCP PCB */
 483 };
 484
 485 #ifdef SYSCTL_DECL
 486 SYSCTL_DECL(_net_inet_mptcp);
 487 #endif /* SYSCTL_DECL */
 488
 489 extern struct mppcbinfo mtcbinfo;
 490 extern struct pr_usrreqs mptcp_usrreqs;
 491 extern os_log_t mptcp_log_handle;
 492
 493 /* Encryption algorithm related definitions */
 494 #define SHA1_TRUNCATED          8
 495
 496 /* MPTCP Debugging Levels */
 497 #define MPTCP_LOGLVL_NONE       0x0     /* No debug logging */
 498 #define MPTCP_LOGLVL_ERR        0x1     /* Errors in execution are logged */
 499 #define MPTCP_LOGLVL_LOG        0x2     /* Important logs */
 500 #define MPTCP_LOGLVL_VERBOSE    0x4     /* Verbose logs */
 501
 502 /* MPTCP sub-components for debug logging */
 503 #define MPTCP_NO_DBG            0x00    /* No areas are logged */
 504 #define MPTCP_STATE_DBG         0x01    /* State machine logging */
 505 #define MPTCP_SOCKET_DBG        0x02    /* Socket call logging */
 506 #define MPTCP_SENDER_DBG        0x04    /* Sender side logging */
 507 #define MPTCP_RECEIVER_DBG      0x08    /* Receiver logging */
 508 #define MPTCP_EVENTS_DBG        0x10    /* Subflow events logging */
 509
 510 /* Mask to obtain 32-bit portion of data sequence number */
 511 #define MPTCP_DATASEQ_LOW32_MASK        (0xffffffff)
 512 #define MPTCP_DATASEQ_LOW32(seq)        (seq & MPTCP_DATASEQ_LOW32_MASK)
 513
 514 /* Mask to obtain upper 32-bit portion of data sequence number */
 515 #define MPTCP_DATASEQ_HIGH32_MASK       (0xffffffff00000000)
 516 #define MPTCP_DATASEQ_HIGH32(seq)       (seq & MPTCP_DATASEQ_HIGH32_MASK)
 517
 518 /* Mask to obtain 32-bit portion of data ack */
 519 #define MPTCP_DATAACK_LOW32_MASK        (0xffffffff)
 520 #define MPTCP_DATAACK_LOW32(ack)        (ack & MPTCP_DATAACK_LOW32_MASK)
 521
 522 /* Mask to obtain upper 32-bit portion of data ack */
 523 #define MPTCP_DATAACK_HIGH32_MASK       (0xffffffff00000000)
 524 #define MPTCP_DATAACK_HIGH32(ack)       (ack & MPTCP_DATAACK_HIGH32_MASK)
 525
 526 /*
 527  * x is the 64-bit data sequence number, y the 32-bit data seq number to be
 528  * extended. z is y extended to the appropriate 64-bit value.
 529  * This algorithm is based on the fact that subflow level window sizes are
 530  * at the maximum 2**30 (in reality, they are a lot lesser). A high throughput
 531  * application sending on a large number of subflows can in theory have very
 532  * large MPTCP level send and receive windows. In which case, 64 bit DSNs
 533  * must be sent in place of 32 bit DSNs on wire. For us, with 2 subflows at
 534  * 512K each, sequence wraparound detection can be done by checking whether
 535  * the 32-bit value obtained on wire is 2**31 bytes apart from the stored
 536  * lower 32-bits of the Data Sequence Number. Bogus DSNs are dropped by
 537  * comparing against rwnd. Bogus DSNs within rwnd cannot be protected against
 538  * and are as weak as bogus TCP sequence numbers.
 539  */
 540 #define MPTCP_EXTEND_DSN(x, y, z) {                                     \
 541         if ((MPTCP_DATASEQ_LOW32(x) > y) &&                             \
 542             ((((u_int32_t)MPTCP_DATASEQ_LOW32(x)) - (u_int32_t)y) >=    \
 543             (u_int32_t)(1 << 31))) {                                    \
 544                 /*                                                      \
 545                  * y wrapped around and x and y are 2**31 bytes  apart  \
 546                  */                                                     \
 547                 z = MPTCP_DATASEQ_HIGH32(x) + 0x100000000;              \
 548                 z |= y;                                                 \
 549         } else if ((MPTCP_DATASEQ_LOW32(x) < y) &&                      \
 550             (((u_int32_t)y -                                            \
 551             ((u_int32_t)MPTCP_DATASEQ_LOW32(x))) >=                     \
 552             (u_int32_t)(1 << 31))) {                                    \
 553                 /*                                                      \
 554                  * x wrapped around and x and y are 2**31 apart         \
 555                  */                                                     \
 556                 z = MPTCP_DATASEQ_HIGH32(x) - 0x100000000;              \
 557                 z |= y;                                                 \
 558         } else {                                                        \
 559                 z = MPTCP_DATASEQ_HIGH32(x) | y;                        \
 560         }                                                               \
 561 }
 562
 563 #define mptcplog(x, y, z)       do {                                    \
 564         if ((mptcp_dbg_area & y) && (mptcp_dbg_level & z))              \
 565                 log x;                                                  \
 566 } while (0)
 567
 568 extern int mptcp_enable;        /* Multipath TCP */
 569 extern int mptcp_mpcap_retries; /* Multipath TCP retries */
 570 extern int mptcp_join_retries;  /* Multipath TCP Join retries */
 571 extern int mptcp_dss_csum;      /* Multipath DSS Option checksum */
 572 extern int mptcp_fail_thresh;   /* Multipath failover thresh of retransmits */
 573 extern int mptcp_subflow_keeptime; /* Multipath subflow TCP_KEEPALIVE opt */
 574 extern uint32_t mptcp_dbg_level;        /* Multipath TCP debugging level */
 575 extern uint32_t mptcp_dbg_area; /* Multipath TCP debugging area */
 576 extern int mptcp_developer_mode;        /* Allow aggregation mode */
 577
 578 extern int tcp_jack_rxmt;       /* Join ACK retransmission value in msecs */
 579
 580 __BEGIN_DECLS
 581 extern void mptcp_init(struct protosw *, struct domain *);
 582 extern int mptcp_ctloutput(struct socket *, struct sockopt *);
 583 extern int mptcp_sescreate(struct mppcb *);
 584 extern void mptcp_check_subflows_and_add(struct mptses *);
 585 extern int mptcp_get_statsindex(struct mptcp_itf_stats *stats,
 586                                 const struct mptsub *mpts);
 587 extern void mptcpstats_inc_switch(struct mptses *, const struct mptsub *);
 588 extern struct mptses *mptcp_drop(struct mptses *, struct mptcb *, int);
 589 extern struct mptses *mptcp_close(struct mptses *, struct mptcb *);
 590 extern int mptcp_lock(struct socket *, int, void *);
 591 extern int mptcp_unlock(struct socket *, int, void *);
 592 extern lck_mtx_t *mptcp_getlock(struct socket *, int);
 593 extern void mptcp_subflow_workloop(struct mptses *);
 594
 595 extern void mptcp_sched_create_subflows(struct mptses *);
 596
 597 extern void mptcp_finish_usrclosed(struct mptses *mpte);
 598 extern struct mptopt *mptcp_sopt_alloc(int);
 599 extern const char *mptcp_sopt2str(int, int);
 600 extern void mptcp_sopt_free(struct mptopt *);
 601 extern void mptcp_sopt_insert(struct mptses *, struct mptopt *);
 602 extern void mptcp_sopt_remove(struct mptses *, struct mptopt *);
 603 extern struct mptopt *mptcp_sopt_find(struct mptses *, struct sockopt *);
 604
 605 extern int mptcp_subflow_add(struct mptses *, struct sockaddr *,
 606     struct sockaddr *, uint32_t, sae_connid_t *);
 607 extern void mptcpstats_update(struct mptcp_itf_stats *stats, struct mptsub *mpts);
 608 extern void mptcp_subflow_del(struct mptses *, struct mptsub *);
 609
 610 #define MPTCP_SUBOUT_PROBING    0x01
 611 extern int mptcp_subflow_output(struct mptses *mpte, struct mptsub *mpts, int flags);
 612 extern void mptcp_clean_reinjectq(struct mptses *mpte);
 613 extern void mptcp_subflow_shutdown(struct mptses *, struct mptsub *);
 614 extern void mptcp_subflow_disconnect(struct mptses *, struct mptsub *);
 615 extern int mptcp_subflow_sosetopt(struct mptses *, struct mptsub *,
 616     struct mptopt *);
 617 extern int mptcp_subflow_sogetopt(struct mptses *, struct socket *,
 618     struct mptopt *);
 619
 620 extern void mptcp_input(struct mptses *, struct mbuf *);
 621 extern boolean_t mptcp_can_send_more(struct mptcb *mp_tp, boolean_t ignore_reinject);
 622 extern int mptcp_output(struct mptses *);
 623 extern void mptcp_close_fsm(struct mptcb *, uint32_t);
 624
 625 extern void mptcp_hmac_sha1(mptcp_key_t, mptcp_key_t, u_int32_t, u_int32_t,
 626     u_char*);
 627 extern void mptcp_get_hmac(mptcp_addr_id, struct mptcb *, u_char *);
 628 extern void mptcp_get_rands(mptcp_addr_id, struct mptcb *, u_int32_t *,
 629     u_int32_t *);
 630 extern void mptcp_set_raddr_rand(mptcp_addr_id, struct mptcb *, mptcp_addr_id,
 631     u_int32_t);
 632 extern int mptcp_init_remote_parms(struct mptcb *);
 633 extern boolean_t mptcp_ok_to_keepalive(struct mptcb *);
 634 extern void mptcp_insert_dsn(struct mppcb *, struct mbuf *);
 635 extern void mptcp_output_getm_dsnmap32(struct socket *so, int off,
 636                                        uint32_t *dsn, uint32_t *relseq,
 637                                        uint16_t *data_len, uint16_t *dss_csum);
 638 extern void mptcp_output_getm_dsnmap64(struct socket *so, int off,
 639                                        uint64_t *dsn, uint32_t *relseq,
 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 *, struct mptsub *,
 643     struct mptsub **);
 644 extern int mptcp_get_map_for_dsn(struct socket *, u_int64_t, u_int32_t *);
 645 extern int32_t mptcp_adj_sendlen(struct socket *so, int32_t off);
 646 extern void mptcp_sbrcv_grow(struct mptcb *mp_tp);
 647 extern int32_t mptcp_sbspace(struct mptcb *);
 648 extern void mptcp_notify_mpready(struct socket *);
 649 extern void mptcp_notify_mpfail(struct socket *);
 650 extern void mptcp_notify_close(struct socket *);
 651 extern boolean_t mptcp_no_rto_spike(struct socket*);
 652 extern int mptcp_set_notsent_lowat(struct mptses *mpte, int optval);
 653 extern u_int32_t mptcp_get_notsent_lowat(struct mptses *mpte);
 654 extern int mptcp_notsent_lowat_check(struct socket *so);
 655 extern void mptcp_ask_symptoms(struct mptses *mpte);
 656 extern void mptcp_control_register(void);
 657 extern int mptcp_is_wifi_unusable(struct mptses *mpte);
 658 extern boolean_t mptcp_subflow_is_bad(struct mptses *mpte, struct mptsub *mpts);
 659 extern void mptcp_ask_for_nat64(struct ifnet *ifp);
 660 extern void mptcp_session_necp_cb(void *, int, uint32_t, uint32_t, bool *);
 661 extern void mptcp_set_restrictions(struct socket *mp_so);
 662 extern int mptcp_freeq(struct mptcb *);
 663 extern void mptcp_set_cellicon(struct mptses *mpte);
 664 extern void mptcp_unset_cellicon(void);
 665 extern void mptcp_reset_rexmit_state(struct tcpcb *tp);
 666 extern void mptcp_reset_keepalive(struct tcpcb *tp);
 667 extern int mptcp_validate_csum(struct tcpcb *tp, struct mbuf *m, uint64_t dsn,
 668                                uint32_t sseq, uint16_t dlen, uint16_t csum,
 669                                uint16_t dfin);
 670 __END_DECLS
 671
 672 #endif /* BSD_KERNEL_PRIVATE */
 673 #ifdef PRIVATE
 674
 675 typedef struct mptcp_flow {
 676         size_t                  flow_len;
 677         size_t                  flow_tcpci_offset;
 678         uint32_t                flow_flags;
 679         sae_connid_t            flow_cid;
 680         struct sockaddr_storage flow_src;
 681         struct sockaddr_storage flow_dst;
 682         uint32_t                flow_relseq;    /* last subflow rel seq# */
 683         int32_t                 flow_soerror;   /* subflow level error */
 684         uint32_t                flow_probecnt;  /* number of probes sent */
 685         conninfo_tcp_t          flow_ci;        /* must be the last field */
 686 } mptcp_flow_t;
 687
 688 typedef struct conninfo_mptcp {
 689         size_t          mptcpci_len;
 690         size_t          mptcpci_flow_offset;    /* offsetof first flow */
 691         size_t          mptcpci_nflows;         /* number of subflows */
 692         uint32_t        mptcpci_state;          /* MPTCP level state */
 693         uint32_t        mptcpci_mpte_flags;     /* Session flags */
 694         uint32_t        mptcpci_flags;          /* MPTCB flags */
 695         uint32_t        mptcpci_ltoken;         /* local token */
 696         uint32_t        mptcpci_rtoken;         /* remote token */
 697         uint32_t        mptcpci_notsent_lowat;  /* NOTSENT_LOWAT */
 698
 699         /* Send side */
 700         uint64_t        mptcpci_snduna;         /* DSN of last unacked byte */
 701         uint64_t        mptcpci_sndnxt;         /* DSN of next byte to send */
 702         uint64_t        mptcpci_sndmax;         /* DSN of max byte sent */
 703         uint64_t        mptcpci_lidsn;          /* Local IDSN */
 704         uint32_t        mptcpci_sndwnd;         /* Send window snapshot */
 705
 706         /* Receive side */
 707         uint64_t        mptcpci_rcvnxt;         /* Next expected DSN */
 708         uint64_t        mptcpci_rcvatmark;      /* Session level rcvnxt */
 709         uint64_t        mptcpci_ridsn;          /* Peer's IDSN */
 710         uint32_t        mptcpci_rcvwnd;         /* Receive window */
 711
 712         uint8_t         mptcpci_mpte_addrid;    /* last addr id */
 713
 714         mptcp_flow_t    mptcpci_flows[1];
 715 } conninfo_mptcp_t;
 716
 717 /* Use SymptomsD notifications of wifi and cell status in subflow selection */
 718 #define MPTCP_KERN_CTL_NAME    "com.apple.network.advisory"
 719 typedef struct symptoms_advisory {
 720         union {
 721                 uint32_t        sa_nwk_status_int;
 722                 struct {
 723                         union {
 724 #define SYMPTOMS_ADVISORY_NOCOMMENT     0x0000
 725 #define SYMPTOMS_ADVISORY_USEAPP        0xFFFF /* Very ugly workaround to avoid breaking backwards compatibility - ToDo: Fix it in +1 */
 726                                 uint16_t        sa_nwk_status;
 727                                 struct {
 728 #define SYMPTOMS_ADVISORY_WIFI_BAD     0x01
 729 #define SYMPTOMS_ADVISORY_WIFI_OK      0x02
 730                                         uint8_t sa_wifi_status;
 731 #define SYMPTOMS_ADVISORY_CELL_BAD     0x01
 732 #define SYMPTOMS_ADVISORY_CELL_OK      0x02
 733                                         uint8_t sa_cell_status;
 734                                 };
 735                         };
 736                         uint16_t        sa_unused;
 737                 };
 738         };
 739 } symptoms_advisory_t;
 740
 741 struct mptcp_symptoms_ask_uuid {
 742         uint32_t        cmd;
 743 #define MPTCP_SYMPTOMS_ASK_UUID         1
 744         uuid_t          uuid;
 745         uint32_t        priority;
 746 #define MPTCP_SYMPTOMS_UNKNOWN          0
 747 #define MPTCP_SYMPTOMS_BACKGROUND       1
 748 #define MPTCP_SYMPTOMS_FOREGROUND       2
 749 };
 750
 751 struct kev_mptcp_data {
 752         int value;
 753 };
 754
 755 #endif /* PRIVATE */
 756 #endif /* _NETINET_MPTCP_VAR_H_ */