bsd/netinet/mptcp_var.h

   1 /*
   2  * Copyright (c) 2012-2020 Apple Inc. All rights reserved.
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  13  * terms of an Apple operating system software license agreement.
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  17  *
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  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 #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
  99         uint16_t        mpte_alternate_port;    /* Alternate port for subflow establishment (network-byte-order) */
 100
 101         int mpte_epid;
 102         uuid_t mpte_euuid;
 103
 104         struct mptsub   *mpte_active_sub;       /* ptr to last active subf */
 105         uint16_t mpte_flags;                    /* per mptcp session flags */
 106 #define MPTE_SND_REM_ADDR       0x01            /* Send Remove_addr option */
 107 #define MPTE_SVCTYPE_CHECKED    0x02            /* Did entitlement-check for service-type */
 108 #define MPTE_FIRSTPARTY         0x04            /* First-party app used multipath_extended entitlement */
 109 #define MPTE_ACCESS_GRANTED     0x08            /* Access to cellular has been granted for this connection */
 110 #define MPTE_FORCE_ENABLE       0x10            /* For MPTCP regardless of heuristics to detect middleboxes */
 111 #define MPTE_IN_WORKLOOP        0x20            /* Are we currently inside the workloop ? */
 112 #define MPTE_WORKLOOP_RELAUNCH  0x40            /* Another event got queued, we should restart the workloop */
 113 #define MPTE_UNICAST_IP         0x80            /* New subflows are only being established towards the unicast IP in the ADD_ADDR */
 114 #define MPTE_CELL_PROHIBITED    0x100           /* Cell access has been prohibited based on signal quality */
 115         uint8_t mpte_svctype;                   /* MPTCP Service type */
 116         uint8_t mpte_lost_aid;                  /* storing lost address id */
 117         uint8_t mpte_addrid_last;               /* storing address id parm */
 118
 119 #define MPTE_ITFINFO_SIZE       4
 120         uint32_t        mpte_itfinfo_size;
 121         struct mpt_itf_info     _mpte_itfinfo[MPTE_ITFINFO_SIZE];
 122         struct mpt_itf_info     *mpte_itfinfo;
 123
 124         struct mbuf             *mpte_reinjectq;
 125
 126         /* The below is used for stats */
 127         uint32_t        mpte_subflow_switches;  /* Number of subflow-switches in sending */
 128         uint32_t        mpte_used_cell:1,
 129             mpte_used_wifi:1,
 130             mpte_initial_cell:1,
 131             mpte_triggered_cell,
 132             mpte_handshake_success:1;
 133
 134         struct mptcp_itf_stats  mpte_itfstats[MPTCP_ITFSTATS_SIZE];
 135         uint64_t                mpte_init_txbytes __attribute__((aligned(8)));
 136         uint64_t                mpte_init_rxbytes __attribute__((aligned(8)));
 137 };
 138
 139 static inline struct socket *
 140 mptetoso(struct mptses *mpte)
 141 {
 142         return mpte->mpte_mppcb->mpp_socket;
 143 }
 144
 145 static inline struct mptses *
 146 mptompte(struct mppcb *mp)
 147 {
 148         return (struct mptses *)mp->mpp_pcbe;
 149 }
 150
 151 static inline struct mptses *
 152 mpsotompte(struct socket *so)
 153 {
 154         return mptompte(mpsotomppcb(so));
 155 }
 156
 157 static inline boolean_t
 158 mpp_try_lock(struct mppcb *mp)
 159 {
 160         if (!lck_mtx_try_lock(&mp->mpp_lock)) {
 161                 return false;
 162         }
 163
 164         VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 165         VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 166
 167         return true;
 168 }
 169
 170 static inline void
 171 mpp_lock(struct mppcb *mp)
 172 {
 173         lck_mtx_lock(&mp->mpp_lock);
 174         VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 175         VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 176 }
 177
 178 static inline void
 179 mpp_unlock(struct mppcb *mp)
 180 {
 181         VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 182         VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 183         lck_mtx_unlock(&mp->mpp_lock);
 184 }
 185
 186 static inline lck_mtx_t *
 187 mpp_getlock(struct mppcb *mp, int flags)
 188 {
 189         if (flags & PR_F_WILLUNLOCK) {
 190                 VERIFY(!(mp->mpp_flags & MPP_INSIDE_OUTPUT));
 191                 VERIFY(!(mp->mpp_flags & MPP_INSIDE_INPUT));
 192         }
 193
 194         return &mp->mpp_lock;
 195 }
 196
 197 static inline int
 198 mptcp_subflow_cwnd_space(struct socket *so)
 199 {
 200         struct tcpcb *tp = sototcpcb(so);
 201         int cwnd = (int)(MIN(tp->snd_wnd, tp->snd_cwnd) - (so->so_snd.sb_cc));
 202
 203         return MIN(cwnd, sbspace(&so->so_snd));
 204 }
 205
 206 static inline bool
 207 mptcp_subflows_need_backup_flag(struct mptses *mpte)
 208 {
 209         return mpte->mpte_svctype < MPTCP_SVCTYPE_AGGREGATE ||
 210                mpte->mpte_svctype == MPTCP_SVCTYPE_PURE_HANDOVER;
 211 }
 212
 213 /*
 214  * MPTCP socket options
 215  */
 216 struct mptopt {
 217         TAILQ_ENTRY(mptopt)     mpo_entry;      /* glue to other options */
 218         uint32_t                mpo_flags;      /* see flags below */
 219         int                     mpo_level;      /* sopt_level */
 220         int                     mpo_name;       /* sopt_name */
 221         int                     mpo_intval;     /* sopt_val */
 222 };
 223
 224 #define MPOF_ATTACHED           0x1     /* attached to MP socket */
 225 #define MPOF_SUBFLOW_OK         0x2     /* can be issued on subflow socket */
 226 #define MPOF_INTERIM            0x4     /* has not been issued on any subflow */
 227
 228 /*
 229  * MPTCP subflow
 230  *
 231  * Note that mpts_flags and mpts_evctl are modified via atomic operations.
 232  */
 233 struct mptsub {
 234         TAILQ_ENTRY(mptsub)   mpts_entry;     /* glue to peer subflows */
 235         uint32_t              mpts_refcnt;    /* reference count */
 236         uint32_t              mpts_flags;     /* see flags below */
 237         long                  mpts_evctl;     /* subflow control events */
 238         sae_connid_t          mpts_connid;    /* subflow connection ID */
 239         int                   mpts_oldintval; /* sopt_val before sosetopt  */
 240         struct mptses         *mpts_mpte;     /* back ptr to MPTCP session */
 241         struct socket         *mpts_socket;   /* subflow socket */
 242         struct sockaddr       *mpts_src;      /* source address */
 243
 244         union {
 245                 /* destination address */
 246                 struct sockaddr         _mpts_dst;
 247                 struct sockaddr_in      _mpts_dst_v4;
 248                 struct sockaddr_in6     _mpts_dst_v6;
 249         } mpts_u_dst;
 250 #define mpts_dst mpts_u_dst._mpts_dst
 251 #define __mpts_dst_v4 mpts_u_dst._mpts_dst_v4
 252 #define __mpts_dst_v6 mpts_u_dst._mpts_dst_v6
 253         u_int32_t               mpts_rel_seq;   /* running count of subflow # */
 254         u_int32_t               mpts_iss;       /* Initial sequence number, taking TFO into account */
 255         u_int32_t               mpts_ifscope;   /* scoped to the interface */
 256         uint32_t                mpts_probesoon; /* send probe after probeto */
 257         uint32_t                mpts_probecnt;  /* number of probes sent */
 258         uint32_t                mpts_maxseg;    /* cached value of t_maxseg */
 259 };
 260
 261 /*
 262  * Valid values for mpts_flags.  In particular:
 263  *
 264  *    - MP_CAPABLE means that the connection is successfully established as
 265  *      MPTCP and data transfer may occur, but is not yet ready for multipath-
 266  *      related semantics until MP_READY.  I.e. if this is on the first subflow,
 267  *      it causes the MPTCP socket to transition to a connected state, except
 268  *      that additional subflows will not be established; they will be marked
 269  *      with PENDING and will be processed when the first subflow is marked
 270  *      with MP_READY.
 271  *
 272  *    - MP_READY implies that an MP_CAPABLE connection has been confirmed as
 273  *      an MPTCP connection.  See notes above.
 274  *
 275  *    - MP_DEGRADED implies that the connection has lost its MPTCP capabilities
 276  *      but data transfer on the MPTCP socket is unaffected.  Any existing
 277  *      PENDING subflows will be disconnected, and further attempts to connect
 278  *      additional subflows will be rejected.
 279  *
 280  * Note that these are per-subflow flags.  The setting and clearing of MP_READY
 281  * reflects the state of the MPTCP connection with regards to its multipath
 282  * semantics, via the MPTCPF_JOIN_READY flag.  Until that flag is set (meaning
 283  * until at least a subflow is marked with MP_READY), further connectx(2)
 284  * attempts to join will be queued.  When the flag is cleared (after it has
 285  * been set), further connectx(2) will fail (and existing queued ones will be
 286  * aborted) and the MPTCP connection loses all of its multipath semantics.
 287  *
 288  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 289  */
 290 #define MPTSF_ATTACHED          0x00000001      /* attached to MPTCP PCB */
 291 #define MPTSF_CONNECTING        0x00000002      /* connection was attempted */
 292 #define MPTSF_CONNECT_PENDING   0x00000004      /* will connect when MPTCP is ready */
 293 #define MPTSF_CONNECTED         0x00000008      /* connection is established */
 294 #define MPTSF_DISCONNECTING     0x00000010      /* disconnection was attempted */
 295 #define MPTSF_DISCONNECTED      0x00000020      /* has been disconnected */
 296 #define MPTSF_MP_CAPABLE        0x00000040      /* connected as a MPTCP subflow */
 297 #define MPTSF_MP_READY          0x00000080      /* MPTCP has been confirmed */
 298 #define MPTSF_MP_DEGRADED       0x00000100      /* has lost its MPTCP capabilities */
 299 #define MPTSF_PREFERRED         0x00000200      /* primary/preferred subflow */
 300 #define MPTSF_SOPT_OLDVAL       0x00000400      /* old option value is valid */
 301 #define MPTSF_SOPT_INPROG       0x00000800      /* sosetopt in progress */
 302 #define MPTSF_FAILINGOVER       0x00001000      /* subflow not used for output */
 303 #define MPTSF_ACTIVE            0x00002000      /* subflow currently in use */
 304 #define MPTSF_MPCAP_CTRSET      0x00004000      /* mpcap counter */
 305 #define MPTSF_CLOSED            0x00008000      /* soclose_locked has been called on this subflow */
 306 #define MPTSF_TFO_REQD          0x00010000      /* TFO requested */
 307 #define MPTSF_CLOSE_REQD        0x00020000      /* A close has been requested from NECP */
 308 #define MPTSF_INITIAL_SUB       0x00040000      /* This is the initial subflow */
 309 #define MPTSF_READ_STALL        0x00080000      /* A read-stall has been detected */
 310 #define MPTSF_WRITE_STALL       0x00100000      /* A write-stall has been detected */
 311 #define MPTSF_FULLY_ESTABLISHED 0x00200000      /* Subflow is fully established and it has been confirmed
 312                                                  * whether or not it supports MPTCP.
 313                                                  * No need for further middlebox-detection.
 314                                                  */
 315 #define MPTSF_CELLICON_SET      0x00400000      /* This subflow set the cellicon */
 316
 317 #define MPTSF_BITS \
 318         "\020\1ATTACHED\2CONNECTING\3PENDING\4CONNECTED\5DISCONNECTING" \
 319         "\6DISCONNECTED\7MP_CAPABLE\10MP_READY\11MP_DEGRADED" \
 320         "\12PREFERRED\13SOPT_OLDVAL" \
 321         "\14SOPT_INPROG\15FAILINGOVER\16ACTIVE\17MPCAP_CTRSET" \
 322         "\20CLOSED\21TFO_REQD\22CLOSEREQD\23INITIALSUB\24READ_STALL" \
 323         "\25WRITE_STALL\26CONFIRMED"
 324
 325 /*
 326  * MPTCP states
 327  * Keep in sync with bsd/dev/dtrace/mptcp.d
 328  */
 329 typedef enum mptcp_state {
 330         MPTCPS_CLOSED           = 0,    /* closed */
 331         MPTCPS_LISTEN           = 1,    /* not yet implemented */
 332         MPTCPS_ESTABLISHED      = 2,    /* MPTCP connection established */
 333         MPTCPS_CLOSE_WAIT       = 3,    /* rcvd DFIN, waiting for close */
 334         MPTCPS_FIN_WAIT_1       = 4,    /* have closed, sent DFIN */
 335         MPTCPS_CLOSING          = 5,    /* closed xchd DFIN, waiting DFIN ACK */
 336         MPTCPS_LAST_ACK         = 6,    /* had DFIN and close; await DFIN ACK */
 337         MPTCPS_FIN_WAIT_2       = 7,    /* have closed, DFIN is acked */
 338         MPTCPS_TIME_WAIT        = 8,    /* in 2*MSL quiet wait after close */
 339         MPTCPS_TERMINATE        = 9,    /* terminal state */
 340 } mptcp_state_t;
 341
 342 typedef u_int64_t       mptcp_key_t;
 343 typedef u_int32_t       mptcp_token_t;
 344 typedef u_int8_t        mptcp_addr_id;
 345
 346
 347 /* Address ID list */
 348 struct mptcp_subf_auth_entry {
 349         LIST_ENTRY(mptcp_subf_auth_entry) msae_next;
 350         u_int32_t       msae_laddr_rand;        /* Local nonce */
 351         u_int32_t       msae_raddr_rand;        /* Remote nonce */
 352         mptcp_addr_id   msae_laddr_id;          /* Local addr ID */
 353         mptcp_addr_id   msae_raddr_id;          /* Remote addr ID */
 354 };
 355
 356 /*
 357  * MPTCP Protocol Control Block
 358  *
 359  * Protected by per-MPTCP mpt_lock.
 360  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 361  */
 362 struct mptcb {
 363         struct mptses  *mpt_mpte;               /* back ptr to MPTCP session */
 364         mptcp_state_t   mpt_state;              /* MPTCP state */
 365         uint32_t        mpt_flags;              /* see flags below */
 366         uint8_t         mpt_version;            /* MPTCP proto version */
 367         uint8_t         mpt_peer_version;       /* Version from peer */
 368         u_short         mpt_softerror;          /* error not yet reported */
 369         /*
 370          * Authentication and metadata invariants
 371          */
 372         mptcp_key_t     mpt_localkey;           /* in network byte order */
 373         mptcp_key_t     mpt_remotekey;          /* in network byte order */
 374         mptcp_token_t   mpt_localtoken;         /* HMAC SHA1 of local key */
 375         mptcp_token_t   mpt_remotetoken;        /* HMAC SHA1 of remote key */
 376
 377         /*
 378          * Timer vars for scenarios where subflow level acks arrive, but
 379          * Data ACKs do not.
 380          */
 381         int             mpt_rxtshift;           /* num of consecutive retrans */
 382         uint64_t        mpt_rxtstart;           /* time at which rxt started */
 383         uint64_t        mpt_rtseq;              /* seq # being tracked */
 384         uint64_t        mpt_timewait;           /* timewait */
 385         uint32_t        mpt_timer_vals;         /* timer related values */
 386         /*
 387          * Sending side
 388          */
 389         uint64_t        mpt_snduna;             /* DSN of last unacked byte */
 390         uint64_t        mpt_sndnxt;             /* DSN of next byte to send */
 391         uint64_t        mpt_sndmax;             /* DSN of max byte sent */
 392         uint64_t        mpt_local_idsn;         /* First byte's DSN */
 393         uint32_t        mpt_sndwnd;
 394         uint64_t        mpt_sndwl1;
 395         uint64_t        mpt_sndwl2;
 396         /*
 397          * Receiving side
 398          */
 399         uint64_t        mpt_rcvnxt;             /* Next expected DSN */
 400         uint64_t        mpt_remote_idsn;        /* Peer's IDSN */
 401         uint64_t        mpt_rcvadv;
 402         uint32_t        mpt_rcvwnd;
 403         LIST_HEAD(, mptcp_subf_auth_entry) mpt_subauth_list; /* address IDs */
 404         /*
 405          * Fastclose
 406          */
 407         uint64_t        mpt_dsn_at_csum_fail;   /* MPFail Opt DSN */
 408         uint32_t        mpt_ssn_at_csum_fail;   /* MPFail Subflow Seq */
 409         /*
 410          * Zombie handling
 411          */
 412 #define MPT_GC_TICKS            (30)
 413 #define MPT_GC_TICKS_FAST       (10)
 414         int32_t         mpt_gc_ticks;           /* Used for zombie deletion */
 415
 416         uint32_t        mpt_notsent_lowat;      /* TCP_NOTSENT_LOWAT support */
 417
 418         struct tsegqe_head      mpt_segq;
 419         uint32_t        mpt_reassqlen;          /* length of reassembly queue */
 420 };
 421
 422 /* valid values for mpt_flags (see also notes on mpts_flags above) */
 423 #define MPTCPF_CHECKSUM                 0x001   /* checksum DSS option */
 424 #define MPTCPF_FALLBACK_TO_TCP          0x002   /* Fallback to TCP */
 425 #define MPTCPF_JOIN_READY               0x004   /* Ready to start 2 or more subflows */
 426 #define MPTCPF_RECVD_MPFAIL             0x008   /* Received MP_FAIL option */
 427 #define MPTCPF_SND_64BITDSN             0x010   /* Send full 64-bit DSN */
 428 #define MPTCPF_SND_64BITACK             0x020   /* Send 64-bit ACK response */
 429 #define MPTCPF_RCVD_64BITACK            0x040   /* Received 64-bit Data ACK */
 430 #define MPTCPF_POST_FALLBACK_SYNC       0x080   /* Post fallback resend data */
 431 #define MPTCPF_FALLBACK_HEURISTIC       0x100   /* Send SYN without MP_CAPABLE due to heuristic */
 432 #define MPTCPF_HEURISTIC_TRAC           0x200   /* Tracked this connection in the heuristics as a failure */
 433 #define MPTCPF_REASS_INPROG             0x400   /* Reassembly is in progress */
 434 #define MPTCPF_UNICAST_IP               0x800
 435
 436 #define MPTCPF_BITS \
 437         "\020\1CHECKSUM\2FALLBACK_TO_TCP\3JOIN_READY\4RECVD_MPFAIL" \
 438         "\5SND_64BITDSN\6SND_64BITACK\7RCVD_64BITACK\10POST_FALLBACK_SYNC" \
 439         "\11FALLBACK_HEURISTIC\12HEURISTIC_TRAC\13REASS_INPROG"
 440
 441 /* valid values for mpt_timer_vals */
 442 #define MPTT_REXMT              0x01    /* Starting Retransmit Timer */
 443 #define MPTT_TW                 0x02    /* Starting Timewait Timer */
 444 #define MPTT_FASTCLOSE          0x04    /* Starting Fastclose wait timer */
 445
 446 /* events for close FSM */
 447 #define MPCE_CLOSE              0x1
 448 #define MPCE_RECV_DATA_ACK      0x2
 449 #define MPCE_RECV_DATA_FIN      0x4
 450
 451 /* mptcb manipulation */
 452 static inline struct mptcb *
 453 tptomptp(struct tcpcb *tp)
 454 {
 455         return tp->t_mptcb;
 456 }
 457
 458 /*
 459  * MPTCP control block and state structures are allocated along with
 460  * the MP protocol control block; the folllowing represents the layout.
 461  */
 462 struct mpp_mtp {
 463         struct mppcb            mpp;            /* Multipath PCB */
 464         struct mptses           mpp_ses;        /* MPTCP session */
 465         struct mptcb            mtcb;           /* MPTCP PCB */
 466 };
 467
 468 #ifdef SYSCTL_DECL
 469 SYSCTL_DECL(_net_inet_mptcp);
 470 #endif /* SYSCTL_DECL */
 471
 472 extern struct mppcbinfo mtcbinfo;
 473 extern struct pr_usrreqs mptcp_usrreqs;
 474 extern os_log_t mptcp_log_handle;
 475
 476 /* Encryption algorithm related definitions */
 477 #define SHA1_TRUNCATED          8
 478
 479 /* MPTCP Debugging Levels */
 480 #define MPTCP_LOGLVL_NONE       0x0     /* No debug logging */
 481 #define MPTCP_LOGLVL_ERR        0x1     /* Errors in execution are logged */
 482 #define MPTCP_LOGLVL_LOG        0x2     /* Important logs */
 483 #define MPTCP_LOGLVL_VERBOSE    0x4     /* Verbose logs */
 484
 485 /* MPTCP sub-components for debug logging */
 486 #define MPTCP_NO_DBG            0x00    /* No areas are logged */
 487 #define MPTCP_STATE_DBG         0x01    /* State machine logging */
 488 #define MPTCP_SOCKET_DBG        0x02    /* Socket call logging */
 489 #define MPTCP_SENDER_DBG        0x04    /* Sender side logging */
 490 #define MPTCP_RECEIVER_DBG      0x08    /* Receiver logging */
 491 #define MPTCP_EVENTS_DBG        0x10    /* Subflow events logging */
 492
 493 /* Mask to obtain 32-bit portion of data sequence number */
 494 #define MPTCP_DATASEQ_LOW32_MASK        (0xffffffff)
 495 #define MPTCP_DATASEQ_LOW32(seq)        (seq & MPTCP_DATASEQ_LOW32_MASK)
 496
 497 /* Mask to obtain upper 32-bit portion of data sequence number */
 498 #define MPTCP_DATASEQ_HIGH32_MASK       (0xffffffff00000000)
 499 #define MPTCP_DATASEQ_HIGH32(seq)       (seq & MPTCP_DATASEQ_HIGH32_MASK)
 500
 501 /* Mask to obtain 32-bit portion of data ack */
 502 #define MPTCP_DATAACK_LOW32_MASK        (0xffffffff)
 503 #define MPTCP_DATAACK_LOW32(ack)        (ack & MPTCP_DATAACK_LOW32_MASK)
 504
 505 /* Mask to obtain upper 32-bit portion of data ack */
 506 #define MPTCP_DATAACK_HIGH32_MASK       (0xffffffff00000000)
 507 #define MPTCP_DATAACK_HIGH32(ack)       (ack & MPTCP_DATAACK_HIGH32_MASK)
 508
 509 /*
 510  * x is the 64-bit data sequence number, y the 32-bit data seq number to be
 511  * extended. z is y extended to the appropriate 64-bit value.
 512  * This algorithm is based on the fact that subflow level window sizes are
 513  * at the maximum 2**30 (in reality, they are a lot lesser). A high throughput
 514  * application sending on a large number of subflows can in theory have very
 515  * large MPTCP level send and receive windows. In which case, 64 bit DSNs
 516  * must be sent in place of 32 bit DSNs on wire. For us, with 2 subflows at
 517  * 512K each, sequence wraparound detection can be done by checking whether
 518  * the 32-bit value obtained on wire is 2**31 bytes apart from the stored
 519  * lower 32-bits of the Data Sequence Number. Bogus DSNs are dropped by
 520  * comparing against rwnd. Bogus DSNs within rwnd cannot be protected against
 521  * and are as weak as bogus TCP sequence numbers.
 522  */
 523 #define MPTCP_EXTEND_DSN(x, y, z) {                                     \
 524         if ((MPTCP_DATASEQ_LOW32(x) > y) &&                             \
 525             ((((u_int32_t)MPTCP_DATASEQ_LOW32(x)) - (u_int32_t)y) >=    \
 526             (u_int32_t)(1U << 31))) {                                    \
 527         /* \
 528          * y wrapped around and x and y are 2**31 bytes  apart \
 529          */                                                             \
 530                 z = MPTCP_DATASEQ_HIGH32(x) + 0x100000000;              \
 531                 z |= y;                                                 \
 532         } else if ((MPTCP_DATASEQ_LOW32(x) < y) &&                      \
 533             (((u_int32_t)y -                                            \
 534             ((u_int32_t)MPTCP_DATASEQ_LOW32(x))) >=                     \
 535             (u_int32_t)(1U << 31))) {                                    \
 536         /* \
 537          * x wrapped around and x and y are 2**31 apart \
 538          */                                                             \
 539                 z = MPTCP_DATASEQ_HIGH32(x) - 0x100000000;              \
 540                 z |= y;                                                 \
 541         } else {                                                        \
 542                 z = MPTCP_DATASEQ_HIGH32(x) | y;                        \
 543         }                                                               \
 544 }
 545
 546 #define mptcplog(x, y, z)       do {                                    \
 547         if ((mptcp_dbg_area & y) && (mptcp_dbg_level & z))              \
 548                 log x;                                                  \
 549 } while (0)
 550
 551 extern int mptcp_enable;        /* Multipath TCP */
 552 extern int mptcp_mpcap_retries; /* Multipath TCP retries */
 553 extern int mptcp_join_retries;  /* Multipath TCP Join retries */
 554 extern int mptcp_dss_csum;      /* Multipath DSS Option checksum */
 555 extern int mptcp_fail_thresh;   /* Multipath failover thresh of retransmits */
 556 extern int mptcp_subflow_keeptime; /* Multipath subflow TCP_KEEPALIVE opt */
 557 extern uint32_t mptcp_dbg_level;        /* Multipath TCP debugging level */
 558 extern uint32_t mptcp_dbg_area; /* Multipath TCP debugging area */
 559 extern int mptcp_developer_mode;        /* Allow aggregation mode */
 560 extern uint32_t mptcp_cellicon_refcount;
 561
 562 #define MPTCP_CELLICON_TOGGLE_RATE      (5 * TCP_RETRANSHZ) /* Only toggle every 5 seconds */
 563
 564 extern int tcp_jack_rxmt;       /* Join ACK retransmission value in msecs */
 565
 566 __BEGIN_DECLS
 567 extern void mptcp_init(struct protosw *, struct domain *);
 568 extern int mptcp_ctloutput(struct socket *, struct sockopt *);
 569 extern int mptcp_session_create(struct mppcb *);
 570 extern boolean_t mptcp_ok_to_create_subflows(struct mptcb *mp_tp);
 571 extern void mptcp_check_subflows_and_add(struct mptses *mpte);
 572 extern void mptcp_check_subflows_and_remove(struct mptses *mpte);
 573 extern void mptcpstats_inc_switch(struct mptses *mpte, const struct mptsub *mpts);
 574 extern void mptcpstats_update(struct mptcp_itf_stats *stats, const struct mptsub *mpts);
 575 extern int mptcpstats_get_index_by_ifindex(struct mptcp_itf_stats *stats, u_short ifindex, boolean_t create);
 576 extern struct mptses *mptcp_drop(struct mptses *mpte, struct mptcb *mp_tp, u_short errno);
 577 extern struct mptses *mptcp_close(struct mptses *, struct mptcb *);
 578 extern int mptcp_lock(struct socket *, int, void *);
 579 extern int mptcp_unlock(struct socket *, int, void *);
 580 extern lck_mtx_t *mptcp_getlock(struct socket *, int);
 581 extern void mptcp_subflow_workloop(struct mptses *);
 582
 583 extern void mptcp_sched_create_subflows(struct mptses *);
 584
 585 extern void mptcp_finish_usrclosed(struct mptses *mpte);
 586 extern struct mptopt *mptcp_sopt_alloc(zalloc_flags_t);
 587 extern const char *mptcp_sopt2str(int, int);
 588 extern void mptcp_sopt_free(struct mptopt *);
 589 extern void mptcp_sopt_insert(struct mptses *, struct mptopt *);
 590 extern void mptcp_sopt_remove(struct mptses *, struct mptopt *);
 591 extern struct mptopt *mptcp_sopt_find(struct mptses *, struct sockopt *);
 592
 593 extern int mptcp_subflow_add(struct mptses *, struct sockaddr *,
 594     struct sockaddr *, uint32_t, sae_connid_t *);
 595 extern void mptcp_subflow_del(struct mptses *, struct mptsub *);
 596
 597 extern void mptcp_handle_input(struct socket *so);
 598 #define MPTCP_SUBOUT_PROBING    0x01
 599 extern int mptcp_subflow_output(struct mptses *mpte, struct mptsub *mpts, int flags);
 600 extern void mptcp_clean_reinjectq(struct mptses *mpte);
 601 extern void mptcp_subflow_shutdown(struct mptses *, struct mptsub *);
 602 extern void mptcp_subflow_disconnect(struct mptses *, struct mptsub *);
 603 extern int mptcp_subflow_sosetopt(struct mptses *, struct mptsub *,
 604     struct mptopt *);
 605 extern int mptcp_subflow_sogetopt(struct mptses *, struct socket *,
 606     struct mptopt *);
 607
 608 extern void mptcp_input(struct mptses *, struct mbuf *);
 609 extern boolean_t mptcp_can_send_more(struct mptcb *mp_tp, boolean_t ignore_reinject);
 610 extern int mptcp_output(struct mptses *);
 611 extern void mptcp_close_fsm(struct mptcb *, uint32_t);
 612
 613 extern void mptcp_hmac_sha1(mptcp_key_t, mptcp_key_t, u_int32_t, u_int32_t,
 614     u_char*);
 615 extern void mptcp_get_hmac(mptcp_addr_id, struct mptcb *, u_char *);
 616 extern void mptcp_get_rands(mptcp_addr_id, struct mptcb *, u_int32_t *,
 617     u_int32_t *);
 618 extern void mptcp_set_raddr_rand(mptcp_addr_id, struct mptcb *, mptcp_addr_id,
 619     u_int32_t);
 620 extern int mptcp_init_remote_parms(struct mptcb *);
 621 extern boolean_t mptcp_ok_to_keepalive(struct mptcb *);
 622 extern void mptcp_insert_dsn(struct mppcb *, struct mbuf *);
 623 extern void mptcp_output_getm_dsnmap32(struct socket *so, int off,
 624     uint32_t *dsn, uint32_t *relseq,
 625     uint16_t *data_len, uint16_t *dss_csum);
 626 extern void mptcp_output_getm_dsnmap64(struct socket *so, int off,
 627     uint64_t *dsn, uint32_t *relseq,
 628     uint16_t *data_len, uint16_t *dss_csum);
 629 extern void mptcp_act_on_txfail(struct socket *);
 630 extern struct mptsub *mptcp_get_subflow(struct mptses *mpte, struct mptsub **preferred);
 631 extern int mptcp_get_map_for_dsn(struct socket *so, uint64_t dsn_fail, uint32_t *tcp_seq);
 632 extern int32_t mptcp_adj_sendlen(struct socket *so, int32_t off);
 633 extern void mptcp_sbrcv_grow(struct mptcb *mp_tp);
 634 extern int32_t mptcp_sbspace(struct mptcb *);
 635 extern void mptcp_notify_mpready(struct socket *);
 636 extern void mptcp_notify_mpfail(struct socket *);
 637 extern void mptcp_notify_close(struct socket *);
 638 extern boolean_t mptcp_no_rto_spike(struct socket*);
 639 extern int mptcp_set_notsent_lowat(struct mptses *mpte, int optval);
 640 extern u_int32_t mptcp_get_notsent_lowat(struct mptses *mpte);
 641 extern int mptcp_notsent_lowat_check(struct socket *so);
 642 extern void mptcp_ask_symptoms(struct mptses *mpte);
 643 extern void mptcp_control_register(void);
 644 extern int mptcp_is_wifi_unusable_for_session(struct mptses *mpte);
 645 extern boolean_t symptoms_is_wifi_lossy(void);
 646 extern void mptcp_session_necp_cb(void *, int, uint32_t, uint32_t, bool *);
 647 extern struct sockaddr *mptcp_get_session_dst(struct mptses *mpte,
 648     boolean_t has_v6, boolean_t has_v4);
 649 extern void mptcp_set_restrictions(struct socket *mp_so);
 650 extern void mptcp_clear_cellicon(void);
 651 extern void mptcp_unset_cellicon(struct mptses *mpte, struct mptsub *mpts, uint32_t val);
 652 extern void mptcp_reset_rexmit_state(struct tcpcb *tp);
 653 extern void mptcp_reset_keepalive(struct tcpcb *tp);
 654 extern int mptcp_validate_csum(struct tcpcb *tp, struct mbuf *m, uint64_t dsn,
 655     uint32_t sseq, uint16_t dlen, uint16_t csum, int dfin);
 656 __END_DECLS
 657
 658 #endif /* BSD_KERNEL_PRIVATE */
 659 #ifdef PRIVATE
 660
 661 typedef struct mptcp_flow {
 662         uint64_t                flow_len;
 663         uint64_t                flow_tcpci_offset;
 664         uint32_t                flow_flags;
 665         sae_connid_t            flow_cid;
 666         struct sockaddr_storage flow_src;
 667         struct sockaddr_storage flow_dst;
 668         uint32_t                flow_relseq;    /* last subflow rel seq# */
 669         int32_t                 flow_soerror;   /* subflow level error */
 670         uint32_t                flow_probecnt;  /* number of probes sent */
 671         conninfo_tcp_t          flow_ci;        /* must be the last field */
 672 } mptcp_flow_t;
 673
 674 typedef struct conninfo_mptcp {
 675         uint64_t        mptcpci_len;
 676         uint64_t        mptcpci_flow_offset;    /* offsetof first flow */
 677         uint64_t        mptcpci_nflows;         /* number of subflows */
 678         uint32_t        mptcpci_state;          /* MPTCP level state */
 679         uint32_t        mptcpci_mpte_flags;     /* Session flags */
 680         uint32_t        mptcpci_flags;          /* MPTCB flags */
 681         uint32_t        mptcpci_ltoken;         /* local token */
 682         uint32_t        mptcpci_rtoken;         /* remote token */
 683         uint32_t        mptcpci_notsent_lowat;  /* NOTSENT_LOWAT */
 684
 685         /* Send side */
 686         uint64_t        mptcpci_snduna;         /* DSN of last unacked byte */
 687         uint64_t        mptcpci_sndnxt;         /* DSN of next byte to send */
 688         uint64_t        mptcpci_sndmax;         /* DSN of max byte sent */
 689         uint64_t        mptcpci_lidsn;          /* Local IDSN */
 690         uint32_t        mptcpci_sndwnd;         /* Send window snapshot */
 691
 692         /* Receive side */
 693         uint64_t        mptcpci_rcvnxt;         /* Next expected DSN */
 694         uint64_t        mptcpci_rcvatmark;      /* Session level rcvnxt */
 695         uint64_t        mptcpci_ridsn;          /* Peer's IDSN */
 696         uint32_t        mptcpci_rcvwnd;         /* Receive window */
 697
 698         uint8_t         mptcpci_mpte_addrid;    /* last addr id */
 699
 700         mptcp_flow_t    mptcpci_flows[1];
 701 } conninfo_mptcp_t;
 702
 703 /* Use SymptomsD notifications of wifi and cell status in subflow selection */
 704 #define MPTCP_KERN_CTL_NAME    "com.apple.network.advisory"
 705 typedef struct symptoms_advisory {
 706         union {
 707                 uint32_t        sa_nwk_status_int;
 708                 struct {
 709                         union {
 710 #define SYMPTOMS_ADVISORY_NOCOMMENT     0x0000
 711 #define SYMPTOMS_ADVISORY_USEAPP        0xFFFF /* Very ugly workaround to avoid breaking backwards compatibility - ToDo: Fix it in +1 */
 712                                 uint16_t        sa_nwk_status;
 713                                 struct {
 714 #define SYMPTOMS_ADVISORY_WIFI_BAD     0x01
 715 #define SYMPTOMS_ADVISORY_WIFI_OK      0x02
 716                                         uint8_t sa_wifi_status;
 717 #define SYMPTOMS_ADVISORY_CELL_BAD     0x01
 718 #define SYMPTOMS_ADVISORY_CELL_OK      0x02
 719                                         uint8_t sa_cell_status;
 720                                 };
 721                         };
 722                         uint16_t        sa_unused;
 723                 };
 724         };
 725 } symptoms_advisory_t;
 726
 727 #define MPTCP_TARGET_BASED_RSSI_THRESHOLD -75
 728 struct mptcp_symptoms_answer {
 729         struct symptoms_advisory advisory;
 730         uuid_t  uuid;
 731         int32_t rssi;
 732 };
 733
 734 struct mptcp_symptoms_ask_uuid {
 735         uint32_t        cmd;
 736 #define MPTCP_SYMPTOMS_ASK_UUID         1
 737         uuid_t          uuid;
 738         uint32_t        priority;
 739 #define MPTCP_SYMPTOMS_UNKNOWN          0
 740 #define MPTCP_SYMPTOMS_BACKGROUND       1
 741 #define MPTCP_SYMPTOMS_FOREGROUND       2
 742 };
 743
 744 struct kev_mptcp_data {
 745         int value;
 746 };
 747
 748 #endif /* PRIVATE */
 749 #endif /* _NETINET_MPTCP_VAR_H_ */