bsd/netinet/mptcp_var.h

   1 /*
   2  * Copyright (c) 2012-2013 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
  24  * limitations under the License.
  25  *
  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
  44 /*
  45  * MPTCP Session
  46  *
  47  * This is an extension to the multipath PCB specific for MPTCP, protected by
  48  * the per-PCB mpp_lock (also the socket's lock); MPTCP thread signalling uses
  49  * its own mpte_thread_lock due to lock ordering constraints.
  50  */
  51 struct mptses {
  52         struct mppcb    *mpte_mppcb;            /* back ptr to multipath PCB */
  53         struct mptcb    *mpte_mptcb;            /* ptr to MPTCP PCB */
  54         TAILQ_HEAD(, mptopt) mpte_sopts;        /* list of socket options */
  55         TAILQ_HEAD(, mptsub) mpte_subflows;     /* list of subflows */
  56         uint16_t        mpte_numflows;          /* # of subflows in list */
  57         uint16_t        mpte_nummpcapflows;     /* # of MP_CAP subflows */
  58         associd_t       mpte_associd;           /* MPTCP association ID */
  59         connid_t        mpte_connid_last;       /* last used connection ID */
  60         /*
  61          * Threading (protected by mpte_thread_lock)
  62          */
  63         decl_lck_mtx_data(, mpte_thread_lock);  /* thread lock */
  64         struct thread   *mpte_thread;           /* worker thread */
  65         uint32_t        mpte_thread_active;     /* thread is running */
  66         uint32_t        mpte_thread_reqs;       /* # of requests for thread */
  67         struct mptsub   *mpte_active_sub;       /* ptr to last active subf */
  68         u_int8_t        mpte_flags;             /* per mptcp session flags */
  69         u_int8_t        mpte_lost_aid;          /* storing lost address id */
  70 };
  71
  72 /*
  73  * Valid values for mpte_flags.
  74  */
  75 #define MPTE_SND_REM_ADDR       0x01            /* Send Remove_addr option */
  76
  77 #define mptompte(mp)    ((struct mptses *)(mp)->mpp_pcbe)
  78
  79 #define MPTE_LOCK_ASSERT_HELD(_mpte)                                    \
  80         lck_mtx_assert(&(_mpte)->mpte_mppcb->mpp_lock, LCK_MTX_ASSERT_OWNED)
  81
  82 #define MPTE_LOCK_ASSERT_NOTHELD(_mpte)                                 \
  83         lck_mtx_assert(&(_mpte)->mpte_mppcb->mpp_lock, LCK_MTX_ASSERT_NOTOWNED)
  84
  85 #define MPTE_LOCK(_mpte)                                                \
  86         lck_mtx_lock(&(_mpte)->mpte_mppcb->mpp_lock)
  87
  88 #define MPTE_LOCK_SPIN(_mpte)                                           \
  89         lck_mtx_lock_spin(&(_mpte)->mpte_mppcb->mpp_lock)
  90
  91 #define MPTE_CONVERT_LOCK(_mpte) do {                                   \
  92         MPTE_LOCK_ASSERT_HELD(_mpte);                                   \
  93         lck_mtx_convert_spin(&(_mpte)->mpte_mppcb->mpp_lock);           \
  94 } while (0)
  95
  96 #define MPTE_UNLOCK(_mpte)                                              \
  97         lck_mtx_unlock(&(_mpte)->mpte_mppcb->mpp_lock)
  98
  99 /*
 100  * MPTCP socket options
 101  */
 102 struct mptopt {
 103         TAILQ_ENTRY(mptopt)     mpo_entry;      /* glue to other options */
 104         uint32_t                mpo_flags;      /* see flags below */
 105         int                     mpo_level;      /* sopt_level */
 106         int                     mpo_name;       /* sopt_name */
 107         int                     mpo_intval;     /* sopt_val */
 108 };
 109
 110 #define MPOF_ATTACHED           0x1     /* attached to MP socket */
 111 #define MPOF_SUBFLOW_OK         0x2     /* can be issued on subflow socket */
 112 #define MPOF_INTERIM            0x4     /* has not been issued on any subflow */
 113
 114 /*
 115  * Structure passed down to TCP during subflow connection establishment
 116  * containing information pertaining to the MPTCP.
 117  */
 118 struct mptsub_connreq {
 119         uint32_t        mpcr_type;      /* see MPTSUB_CONNREQ_* below */
 120         uint32_t        mpcr_ifscope;   /* ifscope parameter to connectx(2) */
 121         struct proc     *mpcr_proc;     /* process issuing connectx(2) */
 122 };
 123
 124 /* valid values for mpcr_type */
 125 #define MPTSUB_CONNREQ_MP_ENABLE        1       /* enable MPTCP */
 126 #define MPTSUB_CONNREQ_MP_ADD           2       /* join an existing MPTCP */
 127
 128 /*
 129  * MPTCP subflow
 130  *
 131  * Protected by the the per-subflow mpts_lock.  Note that mpts_flags
 132  * and mpts_evctl are modified via atomic operations.
 133  */
 134 struct mptsub {
 135         decl_lck_mtx_data(, mpts_lock);         /* per-subflow lock */
 136         TAILQ_ENTRY(mptsub)     mpts_entry;     /* glue to peer subflows */
 137         uint32_t                mpts_refcnt;    /* reference count */
 138         uint32_t                mpts_flags;     /* see flags below */
 139         uint32_t                mpts_evctl;     /* subflow control events */
 140         uint32_t                mpts_family;    /* address family */
 141         connid_t                mpts_connid;    /* subflow connection ID */
 142         int                     mpts_oldintval; /* sopt_val before sosetopt  */
 143         uint32_t                mpts_rank;      /* subflow priority/rank */
 144         int32_t                 mpts_soerror;   /* most recent subflow error */
 145         struct mptses           *mpts_mpte;     /* back ptr to MPTCP session */
 146         struct socket           *mpts_socket;   /* subflow socket */
 147         struct sockaddr_list    *mpts_src_sl;   /* source list */
 148         struct sockaddr_list    *mpts_dst_sl;   /* destination list */
 149         struct ifnet            *mpts_outif;    /* outbound interface */
 150         u_int64_t               mpts_sndnxt;    /* next byte to send in mp so */
 151         u_int32_t               mpts_rel_seq;   /* running count of subflow # */
 152         struct {
 153                 u_int64_t       mptsl_dsn;      /* Data Sequence Number */
 154                 u_int32_t       mptsl_sseq;     /* Corresponding Data Seq */
 155                 u_int32_t       mptsl_len;      /* length of mapping */
 156         } mpts_lastmap;
 157         struct protosw          *mpts_oprotosw; /* original protosw */
 158         struct mptsub_connreq   mpts_mpcr;      /* connection request */
 159 };
 160
 161 /*
 162  * Valid values for mpts_flags.  In particular:
 163  *
 164  *    - MP_CAPABLE means that the connection is successfully established as
 165  *      MPTCP and data transfer may occur, but is not yet ready for multipath-
 166  *      related semantics until MP_READY.  I.e. if this is on the first subflow,
 167  *      it causes the MPTCP socket to transition to a connected state, except
 168  *      that additional subflows will not be established; they will be marked
 169  *      with PENDING and will be processed when the first subflow is marked
 170  *      with MP_READY.
 171  *
 172  *    - MP_READY implies that an MP_CAPABLE connection has been confirmed as
 173  *      an MPTCP connection.  See notes above.
 174  *
 175  *    - MP_DEGRADED implies that the connection has lost its MPTCP capabilities
 176  *      but data transfer on the MPTCP socket is unaffected.  Any existing
 177  *      PENDING subflows will be disconnected, and further attempts to connect
 178  *      additional subflows will be rejected.
 179  *
 180  * Note that these are per-subflow flags.  The setting and clearing of MP_READY
 181  * reflects the state of the MPTCP connection with regards to its multipath
 182  * semantics, via the MPTCPF_JOIN_READY flag.  Until that flag is set (meaning
 183  * until at least a subflow is marked with MP_READY), further connectx(2)
 184  * attempts to join will be queued.  When the flag is cleared (after it has
 185  * been set), further connectx(2) will fail (and existing queued ones will be
 186  * aborted) and the MPTCP connection loses all of its multipath semantics.
 187  *
 188  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 189  */
 190 #define MPTSF_ATTACHED          0x1     /* attached to MPTCP PCB */
 191 #define MPTSF_CONNECTING        0x2     /* connection was attempted */
 192 #define MPTSF_CONNECT_PENDING   0x4     /* will connect when MPTCP is ready */
 193 #define MPTSF_CONNECTED         0x8     /* connection is established */
 194 #define MPTSF_DISCONNECTING     0x10    /* disconnection was attempted */
 195 #define MPTSF_DISCONNECTED      0x20    /* has been disconnected */
 196 #define MPTSF_MP_CAPABLE        0x40    /* connected as a MPTCP subflow */
 197 #define MPTSF_MP_READY          0x80    /* MPTCP has been confirmed */
 198 #define MPTSF_MP_DEGRADED       0x100   /* has lost its MPTCP capabilities */
 199 #define MPTSF_SUSPENDED         0x200   /* write-side is flow controlled */
 200 #define MPTSF_BOUND_IF          0x400   /* subflow bound to an interface */
 201 #define MPTSF_BOUND_IP          0x800   /* subflow bound to a src address */
 202 #define MPTSF_BOUND_PORT        0x1000  /* subflow bound to a src port */
 203 #define MPTSF_PREFERRED         0x2000  /* primary/preferred subflow */
 204 #define MPTSF_SOPT_OLDVAL       0x4000  /* old option value is valid */
 205 #define MPTSF_SOPT_INPROG       0x8000  /* sosetopt in progress */
 206 #define MPTSF_DELETEOK          0x10000 /* subflow can be deleted */
 207 #define MPTSF_FAILINGOVER       0x20000 /* subflow not used for output */
 208 #define MPTSF_ACTIVE            0x40000 /* subflow currently in use */
 209 #define MPTSF_MPCAP_CTRSET      0x80000 /* mpcap counter */
 210
 211 #define MPTSF_BITS \
 212         "\020\1ATTACHED\2CONNECTING\3PENDING\4CONNECTED\5DISCONNECTING" \
 213         "\6DISCONNECTED\7MP_CAPABLE\10MP_READY\11MP_DEGRADED\12SUSPENDED" \
 214         "\13BOUND_IF\14BOUND_IP\15BOUND_PORT\16PREFERRED\17SOPT_OLDVAL" \
 215         "\20SOPT_INPROG\21NOLINGER\22FAILINGOVER\23ACTIVE\24MPCAP_CTRSET"
 216
 217 #define MPTS_LOCK_ASSERT_HELD(_mpts)                                    \
 218         lck_mtx_assert(&(_mpts)->mpts_lock, LCK_MTX_ASSERT_OWNED)
 219
 220 #define MPTS_LOCK_ASSERT_NOTHELD(_mpts)                                 \
 221         lck_mtx_assert(&(_mpts)->mpts_lock, LCK_MTX_ASSERT_NOTOWNED)
 222
 223 #define MPTS_LOCK(_mpts)                                                \
 224         lck_mtx_lock(&(_mpts)->mpts_lock)
 225
 226 #define MPTS_LOCK_SPIN(_mpts)                                           \
 227         lck_mtx_lock_spin(&(_mpts)->mpts_lock)
 228
 229 #define MPTS_CONVERT_LOCK(_mpts) do {                                   \
 230         MPTS_LOCK_ASSERT_HELD(_mpts);                                   \
 231         lck_mtx_convert_spin(&(_mpts)->mpts_lock);                      \
 232 } while (0)
 233
 234 #define MPTS_UNLOCK(_mpts)                                              \
 235         lck_mtx_unlock(&(_mpts)->mpts_lock)
 236
 237 #define MPTS_ADDREF(_mpts)                                              \
 238         mptcp_subflow_addref(_mpts, 0)
 239
 240 #define MPTS_ADDREF_LOCKED(_mpts)                                       \
 241         mptcp_subflow_addref(_mpts, 1)
 242
 243 #define MPTS_REMREF(_mpts)                                              \
 244         mptcp_subflow_remref(_mpts)
 245
 246 /*
 247  * MPTCP states
 248  * Keep in sync with bsd/dev/dtrace/mptcp.d
 249  */
 250 typedef enum mptcp_state {
 251         MPTCPS_CLOSED           = 0,    /* closed */
 252         MPTCPS_LISTEN           = 1,    /* not yet implemented */
 253         MPTCPS_ESTABLISHED      = 2,    /* MPTCP connection established */
 254         MPTCPS_CLOSE_WAIT       = 3,    /* rcvd DFIN, waiting for close */
 255         MPTCPS_FIN_WAIT_1       = 4,    /* have closed, sent DFIN */
 256         MPTCPS_CLOSING          = 5,    /* closed xchd DFIN, waiting DFIN ACK */
 257         MPTCPS_LAST_ACK         = 6,    /* had DFIN and close; await DFIN ACK */
 258         MPTCPS_FIN_WAIT_2       = 7,    /* have closed, DFIN is acked */
 259         MPTCPS_TIME_WAIT        = 8,    /* in 2*MSL quiet wait after close */
 260         MPTCPS_FASTCLOSE_WAIT   = 9,    /* sent MP_FASTCLOSE */
 261 } mptcp_state_t;
 262
 263 typedef u_int64_t       mptcp_key_t;
 264 typedef u_int32_t       mptcp_token_t;
 265 typedef u_int8_t        mptcp_addr_id;
 266
 267
 268 /* Address ID list */
 269 struct mptcp_subf_auth_entry {
 270         LIST_ENTRY(mptcp_subf_auth_entry) msae_next;
 271         u_int32_t       msae_laddr_rand;        /* Local nonce */
 272         u_int32_t       msae_raddr_rand;        /* Remote nonce */
 273         mptcp_addr_id   msae_laddr_id;          /* Local addr ID */
 274         mptcp_addr_id   msae_raddr_id;          /* Remote addr ID */
 275 };
 276
 277 /*
 278  * MPTCP Protocol Control Block
 279  *
 280  * Protected by per-MPTCP mpt_lock.
 281  * Keep in sync with bsd/dev/dtrace/scripts/mptcp.d.
 282  */
 283 struct mptcb {
 284         decl_lck_mtx_data(, mpt_lock);          /* per MPTCP PCB lock */
 285         struct mptses   *mpt_mpte;              /* back ptr to MPTCP session */
 286         mptcp_state_t   mpt_state;              /* MPTCP state */
 287         u_int32_t       mpt_flags;              /* see flags below */
 288         u_int32_t       mpt_refcnt;             /* references held on mptcb */
 289         u_int32_t       mpt_version;            /* MPTCP proto version */
 290         int             mpt_softerror;          /* error not yet reported */
 291         /*
 292          * Authentication and metadata invariants
 293          */
 294         mptcp_key_t     *mpt_localkey;          /* in network byte order */
 295         mptcp_key_t     mpt_remotekey;          /* in network byte order */
 296         mptcp_token_t   mpt_localtoken;         /* HMAC SHA1 of local key */
 297         mptcp_token_t   mpt_remotetoken;        /* HMAC SHA1 of remote key */
 298
 299         /*
 300          * Timer vars for scenarios where subflow level acks arrive, but
 301          * Data ACKs do not.
 302          */
 303         int             mpt_rxtshift;           /* num of consecutive retrans */
 304         u_int32_t       mpt_rxtstart;           /* time at which rxt started */
 305         u_int64_t       mpt_rtseq;              /* seq # being tracked */
 306         u_int32_t       mpt_timer_vals;         /* timer related values */
 307         u_int32_t       mpt_timewait;           /* timewait */
 308         /*
 309          * Sending side
 310          */
 311         u_int64_t       mpt_snduna;             /* DSN of last unacked byte */
 312         u_int64_t       mpt_sndnxt;             /* DSN of next byte to send */
 313         u_int64_t       mpt_sndmax;             /* DSN of max byte sent */
 314         u_int64_t       mpt_local_idsn;         /* First byte's DSN */
 315         u_int32_t       mpt_sndwnd;
 316         /*
 317          * Receiving side
 318          */
 319         u_int64_t       mpt_rcvnxt;             /* Next expected DSN */
 320         u_int64_t       mpt_rcvatmark;          /* mpsocket marker of rcvnxt */
 321         u_int64_t       mpt_remote_idsn;        /* Peer's IDSN */
 322         u_int32_t       mpt_rcvwnd;
 323         LIST_HEAD(, mptcp_subf_auth_entry) mpt_subauth_list; /* address IDs */
 324         /*
 325          * Fastclose
 326          */
 327         u_int64_t       mpt_dsn_at_csum_fail;   /* MPFail Opt DSN */
 328         /*
 329          * Zombie handling
 330          */
 331 #define MPT_GC_TICKS    (60)
 332         int32_t         mpt_gc_ticks;           /* Used for zombie deletion */
 333 };
 334
 335 /* valid values for mpt_flags (see also notes on mpts_flags above) */
 336 #define MPTCPF_CHECKSUM         0x1     /* checksum DSS option */
 337 #define MPTCPF_FALLBACK_TO_TCP  0x2     /* Fallback to TCP */
 338 #define MPTCPF_JOIN_READY       0x4     /* Ready to start 2 or more subflows */
 339 #define MPTCPF_RECVD_MPFAIL     0x8     /* Received MP_FAIL option */
 340 #define MPTCPF_PEEL_OFF         0x10    /* Peel off this socket */
 341 #define MPTCPF_SND_64BITDSN     0x20    /* Send full 64-bit DSN */
 342 #define MPTCPF_SND_64BITACK     0x40    /* Send 64-bit ACK response */
 343 #define MPTCPF_RCVD_64BITACK    0x80    /* Received 64-bit Data ACK */
 344
 345 #define MPTCPF_BITS \
 346         "\020\1CHECKSUM\2FALLBACK_TO_TCP\3JOIN_READY\4RECVD_MPFAIL\5PEEL_OFF" \
 347         "\6SND_64BITDSN\7SND_64BITACK\10RCVD_64BITACK"
 348
 349 /* valid values for mpt_timer_vals */
 350 #define MPTT_REXMT      0x01    /* Starting Retransmit Timer */
 351 #define MPTT_TW         0x02    /* Starting Timewait Timer */
 352 #define MPTT_FASTCLOSE  0x04    /* Starting Fastclose wait timer */
 353
 354 #define MPT_LOCK_ASSERT_HELD(_mpt)                                      \
 355         lck_mtx_assert(&(_mpt)->mpt_lock, LCK_MTX_ASSERT_OWNED)
 356
 357 #define MPT_LOCK_ASSERT_NOTHELD(_mpt)                                   \
 358         lck_mtx_assert(&(_mpt)->mpt_lock, LCK_MTX_ASSERT_NOTOWNED)
 359
 360 #define MPT_LOCK(_mpt)                                                  \
 361         lck_mtx_lock(&(_mpt)->mpt_lock)
 362
 363 #define MPT_LOCK_SPIN(_mpt)                                             \
 364         lck_mtx_lock_spin(&(_mpt)->mpt_lock)
 365
 366 #define MPT_CONVERT_LOCK(_mpt) do {                                     \
 367         MPT_LOCK_ASSERT_HELD(_mpt);                                     \
 368         lck_mtx_convert_spin(&(_mpt)->mpt_lock);                        \
 369 } while (0)
 370
 371 #define MPT_UNLOCK(_mpt)                                                \
 372         lck_mtx_unlock(&(_mpt)->mpt_lock)
 373
 374 /* events for close FSM */
 375 #define MPCE_CLOSE              0x1
 376 #define MPCE_RECV_DATA_ACK      0x2
 377 #define MPCE_RECV_DATA_FIN      0x4
 378
 379 /* mptcb manipulation */
 380 #define tptomptp(tp)    ((struct mptcb *)((tp)->t_mptcb))
 381
 382 /*
 383  * MPTCP control block and state structures are allocated along with
 384  * the MP protocol control block; the folllowing represents the layout.
 385  */
 386 struct mpp_mtp {
 387         struct mppcb            mpp;            /* Multipath PCB */
 388         struct mptses           mpp_ses;        /* MPTCP session */
 389         struct mptcb            mtcb;           /* MPTCP PCB */
 390 };
 391
 392 #ifdef SYSCTL_DECL
 393 SYSCTL_DECL(_net_inet_mptcp);
 394 #endif /* SYSCTL_DECL */
 395
 396 extern struct mppcbinfo mtcbinfo;
 397 extern struct pr_usrreqs mptcp_usrreqs;
 398
 399 /* Encryption algorithm related definitions */
 400 #define MPTCP_SHA1_RESULTLEN    20
 401 #define SHA1_TRUNCATED          8
 402
 403 /* List of valid keys to use for MPTCP connections */
 404 #define MPTCP_KEY_DIGEST_LEN            (MPTCP_SHA1_RESULTLEN)
 405 #define MPTCP_MX_KEY_ALLOCS             (256)
 406 #define MPTCP_KEY_PREALLOCS_MX          (16)
 407 #define MPTCP_MX_PREALLOC_ZONE_SZ       (8192)
 408
 409 struct mptcp_key_entry {
 410         LIST_ENTRY(mptcp_key_entry)     mkey_next;
 411         mptcp_key_t                     mkey_value;
 412 #define MKEYF_FREE      0x0
 413 #define MKEYF_INUSE     0x1
 414         u_int32_t                       mkey_flags;
 415         char                            mkey_digest[MPTCP_KEY_DIGEST_LEN];
 416 };
 417
 418 /* structure for managing unique key list */
 419 struct mptcp_keys_pool_head {
 420         struct mptcp_key_entry *lh_first;       /* list of keys */
 421         u_int32_t       mkph_count;             /* total keys in pool */
 422         vm_size_t       mkph_key_elm_sz;        /* size of key entry */
 423         struct zone     *mkph_key_entry_zone;   /* zone for key entry */
 424         decl_lck_mtx_data(, mkph_lock);         /* lock for key list */
 425 };
 426
 427 /* MPTCP Receive Window */
 428 #define MPTCP_RWIN_MAX  (1<<16)
 429
 430 /* MPTCP Debugging Levels */
 431 #define MP_NODEBUG              0x0
 432 #define MP_ERR_DEBUG            0x1
 433 #define MP_VERBOSE_DEBUG_1      0x2
 434 #define MP_VERBOSE_DEBUG_2      0x3
 435 #define MP_VERBOSE_DEBUG_3      0x4
 436 #define MP_VERBOSE_DEBUG_4      0x5     /* output path debugging */
 437
 438 /* Mask to obtain 32-bit portion of data sequence number */
 439 #define MPTCP_DATASEQ_LOW32_MASK        (0xffffffff)
 440 #define MPTCP_DATASEQ_LOW32(seq)        (seq & MPTCP_DATASEQ_LOW32_MASK)
 441
 442 /* Mask to obtain upper 32-bit portion of data sequence number */
 443 #define MPTCP_DATASEQ_HIGH32_MASK       (0xffffffff00000000)
 444 #define MPTCP_DATASEQ_HIGH32(seq)       (seq & MPTCP_DATASEQ_HIGH32_MASK)
 445
 446 /* Mask to obtain 32-bit portion of data ack */
 447 #define MPTCP_DATAACK_LOW32_MASK        (0xffffffff)
 448 #define MPTCP_DATAACK_LOW32(ack)        (ack & MPTCP_DATAACK_LOW32_MASK)
 449
 450 /* Mask to obtain upper 32-bit portion of data ack */
 451 #define MPTCP_DATAACK_HIGH32_MASK       (0xffffffff00000000)
 452 #define MPTCP_DATAACK_HIGH32(ack)       (ack & MPTCP_DATAACK_HIGH32_MASK)
 453
 454 /*
 455  * x is the 64-bit data sequence number, y the 32-bit data seq number to be
 456  * extended. z is y extended to the appropriate 64-bit value.
 457  * This algorithm is based on the fact that subflow level window sizes are
 458  * at the maximum 2**30 (in reality, they are a lot lesser). A high throughput
 459  * application sending on a large number of subflows can in theory have very
 460  * large MPTCP level send and receive windows. In which case, 64 bit DSNs
 461  * must be sent in place of 32 bit DSNs on wire. For us, with 2 subflows at
 462  * 512K each, sequence wraparound detection can be done by checking whether
 463  * the 32-bit value obtained on wire is 2**31 bytes apart from the stored
 464  * lower 32-bits of the Data Sequence Number. Bogus DSNs are dropped by
 465  * comparing against rwnd. Bogus DSNs within rwnd cannot be protected against
 466  * and are as weak as bogus TCP sequence numbers.
 467  */
 468 #define MPTCP_EXTEND_DSN(x, y, z) {                                     \
 469         if ((MPTCP_DATASEQ_LOW32(x) > y) &&                             \
 470             ((((u_int32_t)MPTCP_DATASEQ_LOW32(x)) - (u_int32_t)y) >=    \
 471             (u_int32_t)(1 << 31))) {                                    \
 472                 /*                                                      \
 473                  * y wrapped around and x and y are 2**31 bytes  apart  \
 474                  */                                                     \
 475                 z = MPTCP_DATASEQ_HIGH32(x) + 0x100000000;              \
 476                 z |= y;                                                 \
 477         } else if ((MPTCP_DATASEQ_LOW32(x) < y) &&                      \
 478             (((u_int32_t)y -                                            \
 479             ((u_int32_t)MPTCP_DATASEQ_LOW32(x))) >=                     \
 480             (u_int32_t)(1 << 31))) {                                    \
 481                 /*                                                      \
 482                  * x wrapped around and x and y are 2**31 apart         \
 483                  */                                                     \
 484                 z = MPTCP_DATASEQ_HIGH32(x) - 0x100000000;              \
 485                 z |= y;                                                 \
 486         } else {                                                        \
 487                 z = MPTCP_DATASEQ_HIGH32(x) | y;                        \
 488         }                                                               \
 489 }
 490
 491 #define mptcplog(x)     do { if (mptcp_verbose >= 1) log x; } while (0)
 492 #define mptcplog2(x)    do { if (mptcp_verbose >= 2) log x; } while (0)
 493 #define mptcplog3(x)    do { if (mptcp_verbose >= 3) log x; } while (0)
 494
 495 extern int mptcp_enable;        /* Multipath TCP */
 496 extern int mptcp_dbg;           /* Multipath TCP DBG */
 497 extern int mptcp_mpcap_retries; /* Multipath TCP retries */
 498 extern int mptcp_join_retries;  /* Multipath TCP Join retries */
 499 extern int mptcp_dss_csum;      /* Multipath DSS Option checksum */
 500 extern int mptcp_fail_thresh;   /* Multipath failover thresh of retransmits */
 501 extern int mptcp_subflow_keeptime; /* Multipath subflow TCP_KEEPALIVE opt */
 502 extern int mptcp_mpprio_enable; /* MP_PRIO option enable/disable */
 503 extern int mptcp_remaddr_enable;/* REMOVE_ADDR option enable/disable */
 504 extern uint32_t mptcp_verbose;  /* verbose and mptcp_dbg must be unified */
 505 #define MPPCB_LIMIT     16
 506 extern uint32_t mptcp_socket_limit; /* max number of mptcp sockets allowed */
 507 extern int tcp_jack_rxmt;       /* Join ACK retransmission value in msecs */
 508
 509 __BEGIN_DECLS
 510 extern void mptcp_init(struct protosw *, struct domain *);
 511 extern int mptcp_ctloutput(struct socket *, struct sockopt *);
 512 extern struct mptses *mptcp_sescreate(struct socket *, struct mppcb *);
 513 extern void mptcp_drain(void);
 514 extern struct mptses *mptcp_drop(struct mptses *, struct mptcb *, int);
 515 extern struct mptses *mptcp_close(struct mptses *, struct mptcb *);
 516 extern int mptcp_lock(struct socket *, int, void *);
 517 extern int mptcp_unlock(struct socket *, int, void *);
 518 extern lck_mtx_t *mptcp_getlock(struct socket *, int);
 519 extern void mptcp_thread_signal(struct mptses *);
 520 extern void mptcp_flush_sopts(struct mptses *);
 521 extern int mptcp_setconnorder(struct mptses *, connid_t, uint32_t);
 522 extern int mptcp_getconnorder(struct mptses *, connid_t, uint32_t *);
 523
 524 extern struct mptopt *mptcp_sopt_alloc(int);
 525 extern const char *mptcp_sopt2str(int, int, char *, int);
 526 extern void mptcp_sopt_free(struct mptopt *);
 527 extern void mptcp_sopt_insert(struct mptses *, struct mptopt *);
 528 extern void mptcp_sopt_remove(struct mptses *, struct mptopt *);
 529 extern struct mptopt *mptcp_sopt_find(struct mptses *, struct sockopt *);
 530
 531 extern struct mptsub *mptcp_subflow_alloc(int);
 532 extern void mptcp_subflow_free(struct mptsub *);
 533 extern void mptcp_subflow_addref(struct mptsub *, int);
 534 extern int mptcp_subflow_add(struct mptses *, struct mptsub *,
 535     struct proc *, uint32_t);
 536 extern void mptcp_subflow_del(struct mptses *, struct mptsub *, boolean_t);
 537 extern void mptcp_subflow_remref(struct mptsub *);
 538 extern int mptcp_subflow_output(struct mptses *, struct mptsub *);
 539 extern void mptcp_subflow_disconnect(struct mptses *, struct mptsub *,
 540     boolean_t);
 541 extern void mptcp_subflow_sopeeloff(struct mptses *, struct mptsub *,
 542     struct socket *);
 543 extern int mptcp_subflow_sosetopt(struct mptses *, struct socket *,
 544     struct mptopt *);
 545 extern int mptcp_subflow_sogetopt(struct mptses *, struct socket *,
 546     struct mptopt *);
 547
 548 extern void mptcp_input(struct mptses *, struct mbuf *);
 549 extern int mptcp_output(struct mptses *);
 550 extern void mptcp_close_fsm(struct mptcb *, uint32_t);
 551
 552 extern mptcp_token_t mptcp_get_localtoken(void *);
 553 extern mptcp_token_t mptcp_get_remotetoken(void *);
 554
 555 extern u_int64_t mptcp_get_localkey(void *);
 556 extern u_int64_t mptcp_get_remotekey(void *);
 557
 558 extern void mptcp_free_key(mptcp_key_t *key);
 559 extern void mptcp_hmac_sha1(mptcp_key_t, mptcp_key_t, u_int32_t, u_int32_t,
 560     u_char*, int);
 561 extern void mptcp_get_hmac(mptcp_addr_id, struct mptcb *, u_char *, int);
 562 extern void mptcp_get_rands(mptcp_addr_id, struct mptcb *, u_int32_t *,
 563     u_int32_t *);
 564 extern void mptcp_set_raddr_rand(mptcp_addr_id, struct mptcb *, mptcp_addr_id,
 565     u_int32_t);
 566 extern u_int64_t mptcp_get_trunced_hmac(mptcp_addr_id, struct mptcb *mp_tp);
 567 extern int mptcp_generate_token(char *, int, caddr_t, int);
 568 extern int mptcp_generate_idsn(char *, int, caddr_t, int);
 569 extern boolean_t mptcp_ok_to_keepalive(struct mptcb *);
 570 extern void mptcp_insert_dsn(struct mppcb *, struct mbuf *);
 571 extern void  mptcp_output_getm_dsnmap32(struct socket *, int, uint32_t,
 572     u_int32_t *, u_int32_t *, u_int16_t *, u_int64_t *);
 573 extern void  mptcp_output_getm_dsnmap64(struct socket *, int, uint32_t,
 574     u_int64_t *, u_int32_t *, u_int16_t *);
 575 extern void mptcp_send_dfin(struct socket *);
 576 extern void mptcp_act_on_txfail(struct socket *);
 577 extern struct mptsub *mptcp_get_subflow(struct mptses *, struct mptsub *);
 578 extern int mptcp_get_map_for_dsn(struct socket *, u_int64_t, u_int32_t *);
 579 extern int32_t mptcp_adj_sendlen(struct socket *so, int32_t off, int32_t len);
 580 extern int32_t mptcp_sbspace(struct mptcb *);
 581 extern void mptcp_notify_mpready(struct socket *);
 582 extern void mptcp_notify_mpfail(struct socket *);
 583 extern void mptcp_notify_close(struct socket *);
 584 __END_DECLS
 585
 586 #endif /* BSD_KERNEL_PRIVATE */
 587 #ifdef PRIVATE
 588 typedef struct mptcp_flow {
 589         uint32_t                flow_flags;
 590         connid_t                flow_cid;
 591         struct sockaddr_storage flow_src;
 592         struct sockaddr_storage flow_dst;
 593         conninfo_tcp_t          flow_ci;
 594 } mptcp_flow_t;
 595
 596 typedef struct conninfo_mptcp {
 597         size_t          mptcpci_len;
 598         size_t          mptcpci_nflows;
 599         uint32_t        mptcpci_state;
 600         mptcp_flow_t    mptcpci_flows[1];
 601 } conninfo_mptcp_t;
 602
 603 #endif /* PRIVATE */
 604 #endif /* _NETINET_MPTCP_VAR_H_ */