sys/netinet/tcp_usrreq.c

   1 /*
   2  * Copyright (c) 2003, 2004 Jeffrey M. Hsu.  All rights reserved.
   3  * Copyright (c) 2003, 2004 The DragonFly Project.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to The DragonFly Project
   6  * by Jeffrey M. Hsu.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of The DragonFly Project nor the names of its
  17  *    contributors may be used to endorse or promote products derived
  18  *    from this software without specific, prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  30  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Copyright (c) 1982, 1986, 1988, 1993
  36  *      The Regents of the University of California.  All rights reserved.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. All advertising materials mentioning features or use of this software
  47  *    must display the following acknowledgement:
  48  *      This product includes software developed by the University of
  49  *      California, Berkeley and its contributors.
  50  * 4. Neither the name of the University nor the names of its contributors
  51  *    may be used to endorse or promote products derived from this software
  52  *    without specific prior written permission.
  53  *
  54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  64  * SUCH DAMAGE.
  65  *
  66  *      From: @(#)tcp_usrreq.c  8.2 (Berkeley) 1/3/94
  67  * $FreeBSD: src/sys/netinet/tcp_usrreq.c,v 1.51.2.17 2002/10/11 11:46:44 ume Exp $
  68  * $DragonFly: src/sys/netinet/tcp_usrreq.c,v 1.51 2008/09/29 20:52:23 dillon Exp $
  69  */
  70
  71 #include "opt_ipsec.h"
  72 #include "opt_inet.h"
  73 #include "opt_inet6.h"
  74 #include "opt_tcpdebug.h"
  75
  76 #include <sys/param.h>
  77 #include <sys/systm.h>
  78 #include <sys/kernel.h>
  79 #include <sys/malloc.h>
  80 #include <sys/sysctl.h>
  81 #include <sys/globaldata.h>
  82 #include <sys/thread.h>
  83
  84 #include <sys/mbuf.h>
  85 #ifdef INET6
  86 #include <sys/domain.h>
  87 #endif /* INET6 */
  88 #include <sys/socket.h>
  89 #include <sys/socketvar.h>
  90 #include <sys/protosw.h>
  91
  92 #include <sys/thread2.h>
  93 #include <sys/msgport2.h>
  94 #include <sys/socketvar2.h>
  95
  96 #include <net/if.h>
  97 #include <net/netisr.h>
  98 #include <net/route.h>
  99
 100 #include <net/netmsg2.h>
 101
 102 #include <netinet/in.h>
 103 #include <netinet/in_systm.h>
 104 #ifdef INET6
 105 #include <netinet/ip6.h>
 106 #endif
 107 #include <netinet/in_pcb.h>
 108 #ifdef INET6
 109 #include <netinet6/in6_pcb.h>
 110 #endif
 111 #include <netinet/in_var.h>
 112 #include <netinet/ip_var.h>
 113 #ifdef INET6
 114 #include <netinet6/ip6_var.h>
 115 #include <netinet6/tcp6_var.h>
 116 #endif
 117 #include <netinet/tcp.h>
 118 #include <netinet/tcp_fsm.h>
 119 #include <netinet/tcp_seq.h>
 120 #include <netinet/tcp_timer.h>
 121 #include <netinet/tcp_timer2.h>
 122 #include <netinet/tcp_var.h>
 123 #include <netinet/tcpip.h>
 124 #ifdef TCPDEBUG
 125 #include <netinet/tcp_debug.h>
 126 #endif
 127
 128 #ifdef IPSEC
 129 #include <netinet6/ipsec.h>
 130 #endif /*IPSEC*/
 131
 132 /*
 133  * TCP protocol interface to socket abstraction.
 134  */
 135 extern  char *tcpstates[];      /* XXX ??? */
 136
 137 static int      tcp_attach (struct socket *, struct pru_attach_info *);
 138 static void     tcp_connect (netmsg_t msg);
 139 #ifdef INET6
 140 static void     tcp6_connect (netmsg_t msg);
 141 static int      tcp6_connect_oncpu(struct tcpcb *tp, int flags,
 142                                 struct mbuf **mp,
 143                                 struct sockaddr_in6 *sin6,
 144                                 struct in6_addr *addr6);
 145 #endif /* INET6 */
 146 static struct tcpcb *
 147                 tcp_disconnect (struct tcpcb *);
 148 static struct tcpcb *
 149                 tcp_usrclosed (struct tcpcb *);
 150
 151 #ifdef TCPDEBUG
 152 #define TCPDEBUG0       int ostate = 0
 153 #define TCPDEBUG1()     ostate = tp ? tp->t_state : 0
 154 #define TCPDEBUG2(req)  if (tp && (so->so_options & SO_DEBUG)) \
 155                                 tcp_trace(TA_USER, ostate, tp, 0, 0, req)
 156 #else
 157 #define TCPDEBUG0
 158 #define TCPDEBUG1()
 159 #define TCPDEBUG2(req)
 160 #endif
 161
 162 /*
 163  * TCP attaches to socket via pru_attach(), reserving space,
 164  * and an internet control block.  This is likely occuring on
 165  * cpu0 and may have to move later when we bind/connect.
 166  */
 167 static void
 168 tcp_usr_attach(netmsg_t msg)
 169 {
 170         struct socket *so = msg->base.nm_so;
 171         struct pru_attach_info *ai = msg->attach.nm_ai;
 172         int error;
 173         struct inpcb *inp;
 174         struct tcpcb *tp = 0;
 175         TCPDEBUG0;
 176
 177         soreference(so);
 178         inp = so->so_pcb;
 179         TCPDEBUG1();
 180         if (inp) {
 181                 error = EISCONN;
 182                 goto out;
 183         }
 184
 185         error = tcp_attach(so, ai);
 186         if (error)
 187                 goto out;
 188
 189         if ((so->so_options & SO_LINGER) && so->so_linger == 0)
 190                 so->so_linger = TCP_LINGERTIME;
 191         tp = sototcpcb(so);
 192 out:
 193         sofree(so);             /* from ref above */
 194         TCPDEBUG2(PRU_ATTACH);
 195         lwkt_replymsg(&msg->lmsg, error);
 196 }
 197
 198 /*
 199  * pru_detach() detaches the TCP protocol from the socket.
 200  * If the protocol state is non-embryonic, then can't
 201  * do this directly: have to initiate a pru_disconnect(),
 202  * which may finish later; embryonic TCB's can just
 203  * be discarded here.
 204  */
 205 static void
 206 tcp_usr_detach(netmsg_t msg)
 207 {
 208         struct socket *so = msg->base.nm_so;
 209         int error = 0;
 210         struct inpcb *inp;
 211         struct tcpcb *tp;
 212         TCPDEBUG0;
 213
 214         inp = so->so_pcb;
 215
 216         /*
 217          * If the inp is already detached it may have been due to an async
 218          * close.  Just return as if no error occured.
 219          *
 220          * It's possible for the tcpcb (tp) to disconnect from the inp due
 221          * to tcp_drop()->tcp_close() being called.  This may occur *after*
 222          * the detach message has been queued so we may find a NULL tp here.
 223          */
 224         if (inp) {
 225                 if ((tp = intotcpcb(inp)) != NULL) {
 226                         TCPDEBUG1();
 227                         tp = tcp_disconnect(tp);
 228                         TCPDEBUG2(PRU_DETACH);
 229                 }
 230         }
 231         lwkt_replymsg(&msg->lmsg, error);
 232 }
 233
 234 /*
 235  * NOTE: ignore_error is non-zero for certain disconnection races
 236  * which we want to silently allow, otherwise close() may return
 237  * an unexpected error.
 238  *
 239  * NOTE: The variables (msg) and (tp) are assumed.
 240  */
 241 #define COMMON_START(so, inp, ignore_error)                     \
 242         TCPDEBUG0;                                              \
 243                                                                 \
 244         inp = so->so_pcb;                                       \
 245         do {                                                    \
 246                  if (inp == NULL) {                             \
 247                         error = ignore_error ? 0 : EINVAL;      \
 248                         tp = NULL;                              \
 249                         goto out;                               \
 250                  }                                              \
 251                  tp = intotcpcb(inp);                           \
 252                  TCPDEBUG1();                                   \
 253         } while(0)
 254
 255 #define COMMON_END(req)                                         \
 256         out: do {                                               \
 257                 TCPDEBUG2(req);                                 \
 258                 lwkt_replymsg(&msg->lmsg, error);               \
 259                 return;                                         \
 260         } while(0)
 261
 262 /*
 263  * Give the socket an address.
 264  */
 265 static void
 266 tcp_usr_bind(netmsg_t msg)
 267 {
 268         struct socket *so = msg->bind.base.nm_so;
 269         struct sockaddr *nam = msg->bind.nm_nam;
 270         struct thread *td = msg->bind.nm_td;
 271         int error = 0;
 272         struct inpcb *inp;
 273         struct tcpcb *tp;
 274         struct sockaddr_in *sinp;
 275
 276         COMMON_START(so, inp, 0);
 277
 278         /*
 279          * Must check for multicast addresses and disallow binding
 280          * to them.
 281          */
 282         sinp = (struct sockaddr_in *)nam;
 283         if (sinp->sin_family == AF_INET &&
 284             IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
 285                 error = EAFNOSUPPORT;
 286                 goto out;
 287         }
 288         error = in_pcbbind(inp, nam, td);
 289         if (error)
 290                 goto out;
 291         COMMON_END(PRU_BIND);
 292
 293 }
 294
 295 #ifdef INET6
 296
 297 static void
 298 tcp6_usr_bind(netmsg_t msg)
 299 {
 300         struct socket *so = msg->bind.base.nm_so;
 301         struct sockaddr *nam = msg->bind.nm_nam;
 302         struct thread *td = msg->bind.nm_td;
 303         int error = 0;
 304         struct inpcb *inp;
 305         struct tcpcb *tp;
 306         struct sockaddr_in6 *sin6p;
 307
 308         COMMON_START(so, inp, 0);
 309
 310         /*
 311          * Must check for multicast addresses and disallow binding
 312          * to them.
 313          */
 314         sin6p = (struct sockaddr_in6 *)nam;
 315         if (sin6p->sin6_family == AF_INET6 &&
 316             IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
 317                 error = EAFNOSUPPORT;
 318                 goto out;
 319         }
 320         inp->inp_vflag &= ~INP_IPV4;
 321         inp->inp_vflag |= INP_IPV6;
 322         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 323                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
 324                         inp->inp_vflag |= INP_IPV4;
 325                 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
 326                         struct sockaddr_in sin;
 327
 328                         in6_sin6_2_sin(&sin, sin6p);
 329                         inp->inp_vflag |= INP_IPV4;
 330                         inp->inp_vflag &= ~INP_IPV6;
 331                         error = in_pcbbind(inp, (struct sockaddr *)&sin, td);
 332                         goto out;
 333                 }
 334         }
 335         error = in6_pcbbind(inp, nam, td);
 336         if (error)
 337                 goto out;
 338         COMMON_END(PRU_BIND);
 339 }
 340 #endif /* INET6 */
 341
 342 #ifdef SMP
 343
 344 struct netmsg_inswildcard {
 345         struct netmsg_base      base;
 346         struct inpcb            *nm_inp;
 347 };
 348
 349 static void
 350 in_pcbinswildcardhash_handler(netmsg_t msg)
 351 {
 352         struct netmsg_inswildcard *nm = (struct netmsg_inswildcard *)msg;
 353         int cpu = mycpuid, nextcpu;
 354
 355         in_pcbinswildcardhash_oncpu(nm->nm_inp, &tcbinfo[cpu]);
 356
 357         nextcpu = cpu + 1;
 358         if (nextcpu < ncpus2)
 359                 lwkt_forwardmsg(cpu_portfn(nextcpu), &nm->base.lmsg);
 360         else
 361                 lwkt_replymsg(&nm->base.lmsg, 0);
 362 }
 363
 364 #endif
 365
 366 /*
 367  * Prepare to accept connections.
 368  */
 369 static void
 370 tcp_usr_listen(netmsg_t msg)
 371 {
 372         struct socket *so = msg->listen.base.nm_so;
 373         struct thread *td = msg->listen.nm_td;
 374         int error = 0;
 375         struct inpcb *inp;
 376         struct tcpcb *tp;
 377 #ifdef SMP
 378         struct netmsg_inswildcard nm;
 379 #endif
 380
 381         COMMON_START(so, inp, 0);
 382
 383         if (tp->t_flags & TF_LISTEN)
 384                 goto out;
 385
 386         if (inp->inp_lport == 0) {
 387                 error = in_pcbbind(inp, NULL, td);
 388                 if (error)
 389                         goto out;
 390         }
 391
 392         tp->t_state = TCPS_LISTEN;
 393         tp->t_flags |= TF_LISTEN;
 394         tp->tt_msg = NULL; /* Catch any invalid timer usage */
 395
 396 #ifdef SMP
 397         if (ncpus > 1) {
 398                 /*
 399                  * We have to set the flag because we can't have other cpus
 400                  * messing with our inp's flags.
 401                  */
 402                 KASSERT(!(inp->inp_flags & INP_CONNECTED),
 403                         ("already on connhash\n"));
 404                 KASSERT(!(inp->inp_flags & INP_WILDCARD),
 405                         ("already on wildcardhash\n"));
 406                 KASSERT(!(inp->inp_flags & INP_WILDCARD_MP),
 407                         ("already on MP wildcardhash\n"));
 408                 inp->inp_flags |= INP_WILDCARD_MP;
 409
 410                 KKASSERT(so->so_port == cpu_portfn(0));
 411                 KKASSERT(&curthread->td_msgport == cpu_portfn(0));
 412                 KKASSERT(inp->inp_pcbinfo == &tcbinfo[0]);
 413
 414                 netmsg_init(&nm.base, NULL, &curthread->td_msgport,
 415                             MSGF_PRIORITY, in_pcbinswildcardhash_handler);
 416                 nm.nm_inp = inp;
 417                 lwkt_domsg(cpu_portfn(1), &nm.base.lmsg, 0);
 418         }
 419 #endif
 420         in_pcbinswildcardhash(inp);
 421         COMMON_END(PRU_LISTEN);
 422 }
 423
 424 #ifdef INET6
 425
 426 static void
 427 tcp6_usr_listen(netmsg_t msg)
 428 {
 429         struct socket *so = msg->listen.base.nm_so;
 430         struct thread *td = msg->listen.nm_td;
 431         int error = 0;
 432         struct inpcb *inp;
 433         struct tcpcb *tp;
 434 #ifdef SMP
 435         struct netmsg_inswildcard nm;
 436 #endif
 437
 438         COMMON_START(so, inp, 0);
 439
 440         if (tp->t_flags & TF_LISTEN)
 441                 goto out;
 442
 443         if (inp->inp_lport == 0) {
 444                 if (!(inp->inp_flags & IN6P_IPV6_V6ONLY))
 445                         inp->inp_vflag |= INP_IPV4;
 446                 else
 447                         inp->inp_vflag &= ~INP_IPV4;
 448                 error = in6_pcbbind(inp, NULL, td);
 449                 if (error)
 450                         goto out;
 451         }
 452
 453         tp->t_state = TCPS_LISTEN;
 454         tp->t_flags |= TF_LISTEN;
 455         tp->tt_msg = NULL; /* Catch any invalid timer usage */
 456
 457 #ifdef SMP
 458         if (ncpus > 1) {
 459                 /*
 460                  * We have to set the flag because we can't have other cpus
 461                  * messing with our inp's flags.
 462                  */
 463                 KASSERT(!(inp->inp_flags & INP_CONNECTED),
 464                         ("already on connhash\n"));
 465                 KASSERT(!(inp->inp_flags & INP_WILDCARD),
 466                         ("already on wildcardhash\n"));
 467                 KASSERT(!(inp->inp_flags & INP_WILDCARD_MP),
 468                         ("already on MP wildcardhash\n"));
 469                 inp->inp_flags |= INP_WILDCARD_MP;
 470
 471                 KKASSERT(so->so_port == cpu_portfn(0));
 472                 KKASSERT(&curthread->td_msgport == cpu_portfn(0));
 473                 KKASSERT(inp->inp_pcbinfo == &tcbinfo[0]);
 474
 475                 netmsg_init(&nm.base, NULL, &curthread->td_msgport,
 476                             MSGF_PRIORITY, in_pcbinswildcardhash_handler);
 477                 nm.nm_inp = inp;
 478                 lwkt_domsg(cpu_portfn(1), &nm.base.lmsg, 0);
 479         }
 480 #endif
 481         in_pcbinswildcardhash(inp);
 482         COMMON_END(PRU_LISTEN);
 483 }
 484 #endif /* INET6 */
 485
 486 /*
 487  * Initiate connection to peer.
 488  * Create a template for use in transmissions on this connection.
 489  * Enter SYN_SENT state, and mark socket as connecting.
 490  * Start keep-alive timer, and seed output sequence space.
 491  * Send initial segment on connection.
 492  */
 493 static void
 494 tcp_usr_connect(netmsg_t msg)
 495 {
 496         struct socket *so = msg->connect.base.nm_so;
 497         struct sockaddr *nam = msg->connect.nm_nam;
 498         struct thread *td = msg->connect.nm_td;
 499         int error = 0;
 500         struct inpcb *inp;
 501         struct tcpcb *tp;
 502         struct sockaddr_in *sinp;
 503
 504         COMMON_START(so, inp, 0);
 505
 506         /*
 507          * Must disallow TCP ``connections'' to multicast addresses.
 508          */
 509         sinp = (struct sockaddr_in *)nam;
 510         if (sinp->sin_family == AF_INET
 511             && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
 512                 error = EAFNOSUPPORT;
 513                 goto out;
 514         }
 515
 516         if (!prison_remote_ip(td, (struct sockaddr*)sinp)) {
 517                 error = EAFNOSUPPORT; /* IPv6 only jail */
 518                 goto out;
 519         }
 520
 521         tcp_connect(msg);
 522         /* msg is invalid now */
 523         return;
 524 out:
 525         if (msg->connect.nm_m) {
 526                 m_freem(msg->connect.nm_m);
 527                 msg->connect.nm_m = NULL;
 528         }
 529         lwkt_replymsg(&msg->lmsg, error);
 530 }
 531
 532 #ifdef INET6
 533
 534 static void
 535 tcp6_usr_connect(netmsg_t msg)
 536 {
 537         struct socket *so = msg->connect.base.nm_so;
 538         struct sockaddr *nam = msg->connect.nm_nam;
 539         struct thread *td = msg->connect.nm_td;
 540         int error = 0;
 541         struct inpcb *inp;
 542         struct tcpcb *tp;
 543         struct sockaddr_in6 *sin6p;
 544
 545         COMMON_START(so, inp, 0);
 546
 547         /*
 548          * Must disallow TCP ``connections'' to multicast addresses.
 549          */
 550         sin6p = (struct sockaddr_in6 *)nam;
 551         if (sin6p->sin6_family == AF_INET6
 552             && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
 553                 error = EAFNOSUPPORT;
 554                 goto out;
 555         }
 556
 557         if (!prison_remote_ip(td, nam)) {
 558                 error = EAFNOSUPPORT; /* IPv4 only jail */
 559                 goto out;
 560         }
 561
 562         if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
 563                 struct sockaddr_in *sinp;
 564
 565                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
 566                         error = EINVAL;
 567                         goto out;
 568                 }
 569                 sinp = kmalloc(sizeof(*sinp), M_LWKTMSG, M_INTWAIT);
 570                 in6_sin6_2_sin(sinp, sin6p);
 571                 inp->inp_vflag |= INP_IPV4;
 572                 inp->inp_vflag &= ~INP_IPV6;
 573                 msg->connect.nm_nam = (struct sockaddr *)sinp;
 574                 msg->connect.nm_reconnect |= NMSG_RECONNECT_NAMALLOC;
 575                 tcp_connect(msg);
 576                 /* msg is invalid now */
 577                 return;
 578         }
 579         inp->inp_vflag &= ~INP_IPV4;
 580         inp->inp_vflag |= INP_IPV6;
 581         inp->inp_inc.inc_isipv6 = 1;
 582
 583         msg->connect.nm_reconnect |= NMSG_RECONNECT_FALLBACK;
 584         tcp6_connect(msg);
 585         /* msg is invalid now */
 586         return;
 587 out:
 588         if (msg->connect.nm_m) {
 589                 m_freem(msg->connect.nm_m);
 590                 msg->connect.nm_m = NULL;
 591         }
 592         lwkt_replymsg(&msg->lmsg, error);
 593 }
 594
 595 #endif /* INET6 */
 596
 597 /*
 598  * Initiate disconnect from peer.
 599  * If connection never passed embryonic stage, just drop;
 600  * else if don't need to let data drain, then can just drop anyways,
 601  * else have to begin TCP shutdown process: mark socket disconnecting,
 602  * drain unread data, state switch to reflect user close, and
 603  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
 604  * when peer sends FIN and acks ours.
 605  *
 606  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
 607  */
 608 static void
 609 tcp_usr_disconnect(netmsg_t msg)
 610 {
 611         struct socket *so = msg->disconnect.base.nm_so;
 612         int error = 0;
 613         struct inpcb *inp;
 614         struct tcpcb *tp;
 615
 616         COMMON_START(so, inp, 1);
 617         tp = tcp_disconnect(tp);
 618         COMMON_END(PRU_DISCONNECT);
 619 }
 620
 621 /*
 622  * Accept a connection.  Essentially all the work is
 623  * done at higher levels; just return the address
 624  * of the peer, storing through addr.
 625  */
 626 static void
 627 tcp_usr_accept(netmsg_t msg)
 628 {
 629         struct socket *so = msg->accept.base.nm_so;
 630         struct sockaddr **nam = msg->accept.nm_nam;
 631         int error = 0;
 632         struct inpcb *inp;
 633         struct tcpcb *tp = NULL;
 634         TCPDEBUG0;
 635
 636         inp = so->so_pcb;
 637         if (so->so_state & SS_ISDISCONNECTED) {
 638                 error = ECONNABORTED;
 639                 goto out;
 640         }
 641         if (inp == 0) {
 642                 error = EINVAL;
 643                 goto out;
 644         }
 645
 646         tp = intotcpcb(inp);
 647         TCPDEBUG1();
 648         in_setpeeraddr(so, nam);
 649         COMMON_END(PRU_ACCEPT);
 650 }
 651
 652 #ifdef INET6
 653 static void
 654 tcp6_usr_accept(netmsg_t msg)
 655 {
 656         struct socket *so = msg->accept.base.nm_so;
 657         struct sockaddr **nam = msg->accept.nm_nam;
 658         int error = 0;
 659         struct inpcb *inp;
 660         struct tcpcb *tp = NULL;
 661         TCPDEBUG0;
 662
 663         inp = so->so_pcb;
 664
 665         if (so->so_state & SS_ISDISCONNECTED) {
 666                 error = ECONNABORTED;
 667                 goto out;
 668         }
 669         if (inp == 0) {
 670                 error = EINVAL;
 671                 goto out;
 672         }
 673         tp = intotcpcb(inp);
 674         TCPDEBUG1();
 675         in6_mapped_peeraddr(so, nam);
 676         COMMON_END(PRU_ACCEPT);
 677 }
 678 #endif /* INET6 */
 679 /*
 680  * Mark the connection as being incapable of further output.
 681  */
 682 static void
 683 tcp_usr_shutdown(netmsg_t msg)
 684 {
 685         struct socket *so = msg->shutdown.base.nm_so;
 686         int error = 0;
 687         struct inpcb *inp;
 688         struct tcpcb *tp;
 689
 690         COMMON_START(so, inp, 0);
 691         socantsendmore(so);
 692         tp = tcp_usrclosed(tp);
 693         if (tp)
 694                 error = tcp_output(tp);
 695         COMMON_END(PRU_SHUTDOWN);
 696 }
 697
 698 /*
 699  * After a receive, possibly send window update to peer.
 700  */
 701 static void
 702 tcp_usr_rcvd(netmsg_t msg)
 703 {
 704         struct socket *so = msg->rcvd.base.nm_so;
 705         int error = 0;
 706         struct inpcb *inp;
 707         struct tcpcb *tp;
 708
 709         COMMON_START(so, inp, 0);
 710         tcp_output(tp);
 711         COMMON_END(PRU_RCVD);
 712 }
 713
 714 /*
 715  * Do a send by putting data in output queue and updating urgent
 716  * marker if URG set.  Possibly send more data.  Unlike the other
 717  * pru_*() routines, the mbuf chains are our responsibility.  We
 718  * must either enqueue them or free them.  The other pru_* routines
 719  * generally are caller-frees.
 720  */
 721 static void
 722 tcp_usr_send(netmsg_t msg)
 723 {
 724         struct socket *so = msg->send.base.nm_so;
 725         int flags = msg->send.nm_flags;
 726         struct mbuf *m = msg->send.nm_m;
 727         struct sockaddr *nam = msg->send.nm_addr;
 728         struct mbuf *control = msg->send.nm_control;
 729         struct thread *td = msg->send.nm_td;
 730         int error = 0;
 731         struct inpcb *inp;
 732         struct tcpcb *tp;
 733 #ifdef INET6
 734         int isipv6;
 735 #endif
 736         TCPDEBUG0;
 737
 738         inp = so->so_pcb;
 739
 740         if (inp == NULL) {
 741                 /*
 742                  * OOPS! we lost a race, the TCP session got reset after
 743                  * we checked SS_CANTSENDMORE, eg: while doing uiomove or a
 744                  * network interrupt in the non-critical section of sosend().
 745                  */
 746                 m_freem(m);
 747                 if (control)
 748                         m_freem(control);
 749                 error = ECONNRESET;     /* XXX EPIPE? */
 750                 tp = NULL;
 751                 TCPDEBUG1();
 752                 goto out;
 753         }
 754 #ifdef INET6
 755         isipv6 = nam && nam->sa_family == AF_INET6;
 756 #endif /* INET6 */
 757         tp = intotcpcb(inp);
 758         TCPDEBUG1();
 759         if (control) {
 760                 /* TCP doesn't do control messages (rights, creds, etc) */
 761                 if (control->m_len) {
 762                         m_freem(control);
 763                         m_freem(m);
 764                         error = EINVAL;
 765                         goto out;
 766                 }
 767                 m_freem(control);       /* empty control, just free it */
 768         }
 769
 770         /*
 771          * Don't let too much OOB data build up
 772          */
 773         if (flags & PRUS_OOB) {
 774                 if (ssb_space(&so->so_snd) < -512) {
 775                         m_freem(m);
 776                         error = ENOBUFS;
 777                         goto out;
 778                 }
 779         }
 780
 781         /*
 782          * Do implied connect if not yet connected.  Any data sent
 783          * with the connect is handled by tcp_connect() and friends.
 784          *
 785          * NOTE!  PROTOCOL THREAD MAY BE CHANGED BY THE CONNECT!
 786          */
 787         if (nam && tp->t_state < TCPS_SYN_SENT) {
 788                 kprintf("implied fallback\n");
 789                 msg->connect.nm_nam = nam;
 790                 msg->connect.nm_td = td;
 791                 msg->connect.nm_m = m;
 792                 msg->connect.nm_flags = flags;
 793                 msg->connect.nm_reconnect = NMSG_RECONNECT_FALLBACK;
 794 #ifdef INET6
 795                 if (isipv6)
 796                         tcp6_connect(msg);
 797                 else
 798 #endif /* INET6 */
 799                         tcp_connect(msg);
 800                 /* msg invalid now */
 801                 return;
 802         }
 803
 804         /*
 805          * Pump the data into the socket.
 806          */
 807         if (m)
 808                 ssb_appendstream(&so->so_snd, m);
 809         if (flags & PRUS_OOB) {
 810                 /*
 811                  * According to RFC961 (Assigned Protocols),
 812                  * the urgent pointer points to the last octet
 813                  * of urgent data.  We continue, however,
 814                  * to consider it to indicate the first octet
 815                  * of data past the urgent section.
 816                  * Otherwise, snd_up should be one lower.
 817                  */
 818                 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc;
 819                 tp->t_flags |= TF_FORCE;
 820                 error = tcp_output(tp);
 821                 tp->t_flags &= ~TF_FORCE;
 822         } else {
 823                 if (flags & PRUS_EOF) {
 824                         /*
 825                          * Close the send side of the connection after
 826                          * the data is sent.
 827                          */
 828                         socantsendmore(so);
 829                         tp = tcp_usrclosed(tp);
 830                 }
 831                 if (tp != NULL) {
 832                         if (flags & PRUS_MORETOCOME)
 833                                 tp->t_flags |= TF_MORETOCOME;
 834                         error = tcp_output(tp);
 835                         if (flags & PRUS_MORETOCOME)
 836                                 tp->t_flags &= ~TF_MORETOCOME;
 837                 }
 838         }
 839         COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB :
 840                    ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
 841 }
 842
 843 /*
 844  * NOTE: (so) is referenced from soabort*() and netmsg_pru_abort()
 845  *       will sofree() it when we return.
 846  */
 847 static void
 848 tcp_usr_abort(netmsg_t msg)
 849 {
 850         struct socket *so = msg->abort.base.nm_so;
 851         int error = 0;
 852         struct inpcb *inp;
 853         struct tcpcb *tp;
 854
 855         COMMON_START(so, inp, 1);
 856         tp = tcp_drop(tp, ECONNABORTED);
 857         COMMON_END(PRU_ABORT);
 858 }
 859
 860 /*
 861  * Receive out-of-band data.
 862  */
 863 static void
 864 tcp_usr_rcvoob(netmsg_t msg)
 865 {
 866         struct socket *so = msg->rcvoob.base.nm_so;
 867         struct mbuf *m = msg->rcvoob.nm_m;
 868         int flags = msg->rcvoob.nm_flags;
 869         int error = 0;
 870         struct inpcb *inp;
 871         struct tcpcb *tp;
 872
 873         COMMON_START(so, inp, 0);
 874         if ((so->so_oobmark == 0 &&
 875              (so->so_state & SS_RCVATMARK) == 0) ||
 876             so->so_options & SO_OOBINLINE ||
 877             tp->t_oobflags & TCPOOB_HADDATA) {
 878                 error = EINVAL;
 879                 goto out;
 880         }
 881         if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
 882                 error = EWOULDBLOCK;
 883                 goto out;
 884         }
 885         m->m_len = 1;
 886         *mtod(m, caddr_t) = tp->t_iobc;
 887         if ((flags & MSG_PEEK) == 0)
 888                 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
 889         COMMON_END(PRU_RCVOOB);
 890 }
 891
 892 /* xxx - should be const */
 893 struct pr_usrreqs tcp_usrreqs = {
 894         .pru_abort = tcp_usr_abort,
 895         .pru_accept = tcp_usr_accept,
 896         .pru_attach = tcp_usr_attach,
 897         .pru_bind = tcp_usr_bind,
 898         .pru_connect = tcp_usr_connect,
 899         .pru_connect2 = pr_generic_notsupp,
 900         .pru_control = in_control_dispatch,
 901         .pru_detach = tcp_usr_detach,
 902         .pru_disconnect = tcp_usr_disconnect,
 903         .pru_listen = tcp_usr_listen,
 904         .pru_peeraddr = in_setpeeraddr_dispatch,
 905         .pru_rcvd = tcp_usr_rcvd,
 906         .pru_rcvoob = tcp_usr_rcvoob,
 907         .pru_send = tcp_usr_send,
 908         .pru_sense = pru_sense_null,
 909         .pru_shutdown = tcp_usr_shutdown,
 910         .pru_sockaddr = in_setsockaddr_dispatch,
 911         .pru_sosend = sosend,
 912         .pru_soreceive = soreceive
 913 };
 914
 915 #ifdef INET6
 916 struct pr_usrreqs tcp6_usrreqs = {
 917         .pru_abort = tcp_usr_abort,
 918         .pru_accept = tcp6_usr_accept,
 919         .pru_attach = tcp_usr_attach,
 920         .pru_bind = tcp6_usr_bind,
 921         .pru_connect = tcp6_usr_connect,
 922         .pru_connect2 = pr_generic_notsupp,
 923         .pru_control = in6_control_dispatch,
 924         .pru_detach = tcp_usr_detach,
 925         .pru_disconnect = tcp_usr_disconnect,
 926         .pru_listen = tcp6_usr_listen,
 927         .pru_peeraddr = in6_mapped_peeraddr_dispatch,
 928         .pru_rcvd = tcp_usr_rcvd,
 929         .pru_rcvoob = tcp_usr_rcvoob,
 930         .pru_send = tcp_usr_send,
 931         .pru_sense = pru_sense_null,
 932         .pru_shutdown = tcp_usr_shutdown,
 933         .pru_sockaddr = in6_mapped_sockaddr_dispatch,
 934         .pru_sosend = sosend,
 935         .pru_soreceive = soreceive
 936 };
 937 #endif /* INET6 */
 938
 939 static int
 940 tcp_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf *m,
 941                   struct sockaddr_in *sin, struct sockaddr_in *if_sin)
 942 {
 943         struct inpcb *inp = tp->t_inpcb, *oinp;
 944         struct socket *so = inp->inp_socket;
 945         struct route *ro = &inp->inp_route;
 946
 947         oinp = in_pcblookup_hash(&tcbinfo[mycpu->gd_cpuid],
 948                                  sin->sin_addr, sin->sin_port,
 949                                  (inp->inp_laddr.s_addr != INADDR_ANY ?
 950                                   inp->inp_laddr : if_sin->sin_addr),
 951                                 inp->inp_lport, 0, NULL);
 952         if (oinp != NULL) {
 953                 m_freem(m);
 954                 return (EADDRINUSE);
 955         }
 956         if (inp->inp_laddr.s_addr == INADDR_ANY)
 957                 inp->inp_laddr = if_sin->sin_addr;
 958         inp->inp_faddr = sin->sin_addr;
 959         inp->inp_fport = sin->sin_port;
 960         inp->inp_cpcbinfo = &tcbinfo[mycpu->gd_cpuid];
 961         in_pcbinsconnhash(inp);
 962
 963         /*
 964          * We are now on the inpcb's owner CPU, if the cached route was
 965          * freed because the rtentry's owner CPU is not the current CPU
 966          * (e.g. in tcp_connect()), then we try to reallocate it here with
 967          * the hope that a rtentry may be cloned from a RTF_PRCLONING
 968          * rtentry.
 969          */
 970         if (!(inp->inp_socket->so_options & SO_DONTROUTE) && /*XXX*/
 971             ro->ro_rt == NULL) {
 972                 bzero(&ro->ro_dst, sizeof(struct sockaddr_in));
 973                 ro->ro_dst.sa_family = AF_INET;
 974                 ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
 975                 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr =
 976                         sin->sin_addr;
 977                 rtalloc(ro);
 978         }
 979
 980         /*
 981          * Now that no more errors can occur, change the protocol processing
 982          * port to the current thread (which is the correct thread).
 983          *
 984          * Create TCP timer message now; we are on the tcpcb's owner
 985          * CPU/thread.
 986          */
 987         tcp_create_timermsg(tp, &curthread->td_msgport);
 988
 989         /*
 990          * Compute window scaling to request.  Use a larger scaling then
 991          * needed for the initial receive buffer in case the receive buffer
 992          * gets expanded.
 993          */
 994         if (tp->request_r_scale < TCP_MIN_WINSHIFT)
 995                 tp->request_r_scale = TCP_MIN_WINSHIFT;
 996         while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
 997                (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.ssb_hiwat
 998         ) {
 999                 tp->request_r_scale++;
1000         }
1001
1002         soisconnecting(so);
1003         tcpstat.tcps_connattempt++;
1004         tp->t_state = TCPS_SYN_SENT;
1005         tcp_callout_reset(tp, tp->tt_keep, tcp_keepinit, tcp_timer_keep);
1006         tp->iss = tcp_new_isn(tp);
1007         tcp_sendseqinit(tp);
1008         if (m) {
1009                 ssb_appendstream(&so->so_snd, m);
1010                 m = NULL;
1011                 if (flags & PRUS_OOB)
1012                         tp->snd_up = tp->snd_una + so->so_snd.ssb_cc;
1013         }
1014
1015         /*
1016          * Close the send side of the connection after
1017          * the data is sent if flagged.
1018          */
1019         if ((flags & (PRUS_OOB|PRUS_EOF)) == PRUS_EOF) {
1020                 socantsendmore(so);
1021                 tp = tcp_usrclosed(tp);
1022         }
1023         return (tcp_output(tp));
1024 }
1025
1026 /*
1027  * Common subroutine to open a TCP connection to remote host specified
1028  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1029  * port number if needed.  Call in_pcbladdr to do the routing and to choose
1030  * a local host address (interface).
1031  * Initialize connection parameters and enter SYN-SENT state.
1032  */
1033 static void
1034 tcp_connect(netmsg_t msg)
1035 {
1036         struct socket *so = msg->connect.base.nm_so;
1037         struct sockaddr *nam = msg->connect.nm_nam;
1038         struct thread *td = msg->connect.nm_td;
1039         struct sockaddr_in *sin = (struct sockaddr_in *)nam;
1040         struct sockaddr_in *if_sin;
1041         struct inpcb *inp;
1042         struct tcpcb *tp;
1043         int error;
1044 #ifdef SMP
1045         lwkt_port_t port;
1046 #endif
1047
1048         COMMON_START(so, inp, 0);
1049
1050         /*
1051          * Reconnect our pcb if we have to
1052          */
1053         if (msg->connect.nm_reconnect & NMSG_RECONNECT_RECONNECT) {
1054                 msg->connect.nm_reconnect &= ~NMSG_RECONNECT_RECONNECT;
1055                 in_pcblink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1056         }
1057
1058         /*
1059          * Bind if we have to
1060          */
1061         if (inp->inp_lport == 0) {
1062                 error = in_pcbbind(inp, NULL, td);
1063                 if (error)
1064                         goto out;
1065         }
1066         so = inp->inp_socket;
1067         KKASSERT(so);
1068
1069         /*
1070          * Calculate the correct protocol processing thread.  The connect
1071          * operation must run there.  Set the forwarding port before we
1072          * forward the message or it will get bounced right back to us.
1073          */
1074         error = in_pcbladdr(inp, nam, &if_sin, td);
1075         if (error)
1076                 goto out;
1077
1078 #ifdef SMP
1079         port = tcp_addrport(sin->sin_addr.s_addr, sin->sin_port,
1080                             (inp->inp_laddr.s_addr ?
1081                              inp->inp_laddr.s_addr : if_sin->sin_addr.s_addr),
1082                             inp->inp_lport);
1083
1084         if (port != &curthread->td_msgport) {
1085                 struct route *ro = &inp->inp_route;
1086
1087                 /*
1088                  * in_pcbladdr() may have allocated a route entry for us
1089                  * on the current CPU, but we need a route entry on the
1090                  * inpcb's owner CPU, so free it here.
1091                  */
1092                 if (ro->ro_rt != NULL)
1093                         RTFREE(ro->ro_rt);
1094                 bzero(ro, sizeof(*ro));
1095
1096                 /*
1097                  * We are moving the protocol processing port the socket
1098                  * is on, we have to unlink here and re-link on the
1099                  * target cpu.
1100                  */
1101                 in_pcbunlink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1102                 sosetport(so, port);
1103                 msg->connect.nm_reconnect |= NMSG_RECONNECT_RECONNECT;
1104                 msg->connect.base.nm_dispatch = tcp_connect;
1105
1106                 lwkt_forwardmsg(port, &msg->connect.base.lmsg);
1107                 /* msg invalid now */
1108                 return;
1109         }
1110 #else
1111         KKASSERT(so->so_port == &curthread->td_msgport);
1112 #endif
1113         error = tcp_connect_oncpu(tp, msg->connect.nm_flags,
1114                                   msg->connect.nm_m, sin, if_sin);
1115         msg->connect.nm_m = NULL;
1116 out:
1117         if (msg->connect.nm_m) {
1118                 m_freem(msg->connect.nm_m);
1119                 msg->connect.nm_m = NULL;
1120         }
1121         if (msg->connect.nm_reconnect & NMSG_RECONNECT_NAMALLOC) {
1122                 kfree(msg->connect.nm_nam, M_LWKTMSG);
1123                 msg->connect.nm_nam = NULL;
1124         }
1125         lwkt_replymsg(&msg->connect.base.lmsg, error);
1126         /* msg invalid now */
1127 }
1128
1129 #ifdef INET6
1130
1131 static void
1132 tcp6_connect(netmsg_t msg)
1133 {
1134         struct tcpcb *tp;
1135         struct socket *so = msg->connect.base.nm_so;
1136         struct sockaddr *nam = msg->connect.nm_nam;
1137         struct thread *td = msg->connect.nm_td;
1138         struct inpcb *inp;
1139         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
1140         struct in6_addr *addr6;
1141 #ifdef SMP
1142         lwkt_port_t port;
1143 #endif
1144         int error;
1145
1146         COMMON_START(so, inp, 0);
1147
1148         /*
1149          * Reconnect our pcb if we have to
1150          */
1151         if (msg->connect.nm_reconnect & NMSG_RECONNECT_RECONNECT) {
1152                 msg->connect.nm_reconnect &= ~NMSG_RECONNECT_RECONNECT;
1153                 in_pcblink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1154         }
1155
1156         /*
1157          * Bind if we have to
1158          */
1159         if (inp->inp_lport == 0) {
1160                 error = in6_pcbbind(inp, NULL, td);
1161                 if (error)
1162                         goto out;
1163         }
1164
1165         /*
1166          * Cannot simply call in_pcbconnect, because there might be an
1167          * earlier incarnation of this same connection still in
1168          * TIME_WAIT state, creating an ADDRINUSE error.
1169          */
1170         error = in6_pcbladdr(inp, nam, &addr6, td);
1171         if (error)
1172                 goto out;
1173
1174 #ifdef SMP
1175         port = tcp6_addrport(); /* XXX hack for now, always cpu0 */
1176
1177         if (port != &curthread->td_msgport) {
1178                 struct route *ro = &inp->inp_route;
1179
1180                 /*
1181                  * in_pcbladdr() may have allocated a route entry for us
1182                  * on the current CPU, but we need a route entry on the
1183                  * inpcb's owner CPU, so free it here.
1184                  */
1185                 if (ro->ro_rt != NULL)
1186                         RTFREE(ro->ro_rt);
1187                 bzero(ro, sizeof(*ro));
1188
1189                 in_pcbunlink(so->so_pcb, &tcbinfo[mycpu->gd_cpuid]);
1190                 sosetport(so, port);
1191                 msg->connect.nm_reconnect |= NMSG_RECONNECT_RECONNECT;
1192                 msg->connect.base.nm_dispatch = tcp6_connect;
1193
1194                 lwkt_forwardmsg(port, &msg->connect.base.lmsg);
1195                 /* msg invalid now */
1196                 return;
1197         }
1198 #endif
1199         error = tcp6_connect_oncpu(tp, msg->connect.nm_flags,
1200                                    &msg->connect.nm_m, sin6, addr6);
1201         /* nm_m may still be intact */
1202 out:
1203         if (error && (msg->connect.nm_reconnect & NMSG_RECONNECT_FALLBACK)) {
1204                 tcp_connect(msg);
1205                 /* msg invalid now */
1206         } else {
1207                 if (msg->connect.nm_m) {
1208                         m_freem(msg->connect.nm_m);
1209                         msg->connect.nm_m = NULL;
1210                 }
1211                 if (msg->connect.nm_reconnect & NMSG_RECONNECT_NAMALLOC) {
1212                         kfree(msg->connect.nm_nam, M_LWKTMSG);
1213                         msg->connect.nm_nam = NULL;
1214                 }
1215                 lwkt_replymsg(&msg->connect.base.lmsg, error);
1216                 /* msg invalid now */
1217         }
1218 }
1219
1220 static int
1221 tcp6_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf **mp,
1222                    struct sockaddr_in6 *sin6, struct in6_addr *addr6)
1223 {
1224         struct mbuf *m = *mp;
1225         struct inpcb *inp = tp->t_inpcb;
1226         struct socket *so = inp->inp_socket;
1227         struct inpcb *oinp;
1228
1229         /*
1230          * Cannot simply call in_pcbconnect, because there might be an
1231          * earlier incarnation of this same connection still in
1232          * TIME_WAIT state, creating an ADDRINUSE error.
1233          */
1234         oinp = in6_pcblookup_hash(inp->inp_cpcbinfo,
1235                                   &sin6->sin6_addr, sin6->sin6_port,
1236                                   (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) ?
1237                                       addr6 : &inp->in6p_laddr),
1238                                   inp->inp_lport,  0, NULL);
1239         if (oinp)
1240                 return (EADDRINUSE);
1241
1242         if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
1243                 inp->in6p_laddr = *addr6;
1244         inp->in6p_faddr = sin6->sin6_addr;
1245         inp->inp_fport = sin6->sin6_port;
1246         if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0)
1247                 inp->in6p_flowinfo = sin6->sin6_flowinfo;
1248         in_pcbinsconnhash(inp);
1249
1250         /*
1251          * Now that no more errors can occur, change the protocol processing
1252          * port to the current thread (which is the correct thread).
1253          *
1254          * Create TCP timer message now; we are on the tcpcb's owner
1255          * CPU/thread.
1256          */
1257         tcp_create_timermsg(tp, &curthread->td_msgport);
1258
1259         /* Compute window scaling to request.  */
1260         if (tp->request_r_scale < TCP_MIN_WINSHIFT)
1261                 tp->request_r_scale = TCP_MIN_WINSHIFT;
1262         while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1263             (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.ssb_hiwat) {
1264                 tp->request_r_scale++;
1265         }
1266
1267         soisconnecting(so);
1268         tcpstat.tcps_connattempt++;
1269         tp->t_state = TCPS_SYN_SENT;
1270         tcp_callout_reset(tp, tp->tt_keep, tcp_keepinit, tcp_timer_keep);
1271         tp->iss = tcp_new_isn(tp);
1272         tcp_sendseqinit(tp);
1273         if (m) {
1274                 ssb_appendstream(&so->so_snd, m);
1275                 *mp = NULL;
1276                 if (flags & PRUS_OOB)
1277                         tp->snd_up = tp->snd_una + so->so_snd.ssb_cc;
1278         }
1279
1280         /*
1281          * Close the send side of the connection after
1282          * the data is sent if flagged.
1283          */
1284         if ((flags & (PRUS_OOB|PRUS_EOF)) == PRUS_EOF) {
1285                 socantsendmore(so);
1286                 tp = tcp_usrclosed(tp);
1287         }
1288         return (tcp_output(tp));
1289 }
1290
1291 #endif /* INET6 */
1292
1293 /*
1294  * The new sockopt interface makes it possible for us to block in the
1295  * copyin/out step (if we take a page fault).  Taking a page fault while
1296  * in a critical section is probably a Bad Thing.  (Since sockets and pcbs
1297  * both now use TSM, there probably isn't any need for this function to
1298  * run in a critical section any more.  This needs more examination.)
1299  */
1300 void
1301 tcp_ctloutput(netmsg_t msg)
1302 {
1303         struct socket *so = msg->base.nm_so;
1304         struct sockopt *sopt = msg->ctloutput.nm_sopt;
1305         int     error, opt, optval;
1306         struct  inpcb *inp;
1307         struct  tcpcb *tp;
1308
1309         error = 0;
1310         inp = so->so_pcb;
1311         if (inp == NULL) {
1312                 error = ECONNRESET;
1313                 goto done;
1314         }
1315
1316         if (sopt->sopt_level != IPPROTO_TCP) {
1317 #ifdef INET6
1318                 if (INP_CHECK_SOCKAF(so, AF_INET6))
1319                         ip6_ctloutput_dispatch(msg);
1320                 else
1321 #endif /* INET6 */
1322                 ip_ctloutput(msg);
1323                 /* msg invalid now */
1324                 return;
1325         }
1326         tp = intotcpcb(inp);
1327
1328         switch (sopt->sopt_dir) {
1329         case SOPT_SET:
1330                 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1331                                       sizeof optval);
1332                 if (error)
1333                         break;
1334                 switch (sopt->sopt_name) {
1335                 case TCP_FASTKEEP:
1336                         if (optval > 0) {
1337                                 if ((tp->t_flags & TF_FASTKEEP) == 0) {
1338                                         tp->t_flags |= TF_FASTKEEP;
1339                                         tcp_timer_keep_activity(tp, 0);
1340                                 }
1341                         } else {
1342                                 tp->t_flags &= ~TF_FASTKEEP;
1343                         }
1344                         break;
1345 #ifdef TCP_SIGNATURE
1346                 case TCP_SIGNATURE_ENABLE:
1347                         if (optval > 0)
1348                                 tp->t_flags |= TF_SIGNATURE;
1349                         else
1350                                 tp->t_flags &= ~TF_SIGNATURE;
1351                         break;
1352 #endif /* TCP_SIGNATURE */
1353                 case TCP_NODELAY:
1354                 case TCP_NOOPT:
1355                         switch (sopt->sopt_name) {
1356                         case TCP_NODELAY:
1357                                 opt = TF_NODELAY;
1358                                 break;
1359                         case TCP_NOOPT:
1360                                 opt = TF_NOOPT;
1361                                 break;
1362                         default:
1363                                 opt = 0; /* dead code to fool gcc */
1364                                 break;
1365                         }
1366
1367                         if (optval)
1368                                 tp->t_flags |= opt;
1369                         else
1370                                 tp->t_flags &= ~opt;
1371                         break;
1372
1373                 case TCP_NOPUSH:
1374                         if (optval)
1375                                 tp->t_flags |= TF_NOPUSH;
1376                         else {
1377                                 tp->t_flags &= ~TF_NOPUSH;
1378                                 error = tcp_output(tp);
1379                         }
1380                         break;
1381
1382                 case TCP_MAXSEG:
1383                         /*
1384                          * Must be between 0 and maxseg.  If the requested
1385                          * maxseg is too small to satisfy the desired minmss,
1386                          * pump it up (silently so sysctl modifications of
1387                          * minmss do not create unexpected program failures).
1388                          * Handle degenerate cases.
1389                          */
1390                         if (optval > 0 && optval <= tp->t_maxseg) {
1391                                 if (optval + 40 < tcp_minmss) {
1392                                         optval = tcp_minmss - 40;
1393                                         if (optval < 0)
1394                                                 optval = 1;
1395                                 }
1396                                 tp->t_maxseg = optval;
1397                         } else {
1398                                 error = EINVAL;
1399                         }
1400                         break;
1401
1402                 default:
1403                         error = ENOPROTOOPT;
1404                         break;
1405                 }
1406                 break;
1407
1408         case SOPT_GET:
1409                 switch (sopt->sopt_name) {
1410 #ifdef TCP_SIGNATURE
1411                 case TCP_SIGNATURE_ENABLE:
1412                         optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1413                         break;
1414 #endif /* TCP_SIGNATURE */
1415                 case TCP_NODELAY:
1416                         optval = tp->t_flags & TF_NODELAY;
1417                         break;
1418                 case TCP_MAXSEG:
1419                         optval = tp->t_maxseg;
1420                         break;
1421                 case TCP_NOOPT:
1422                         optval = tp->t_flags & TF_NOOPT;
1423                         break;
1424                 case TCP_NOPUSH:
1425                         optval = tp->t_flags & TF_NOPUSH;
1426                         break;
1427                 default:
1428                         error = ENOPROTOOPT;
1429                         break;
1430                 }
1431                 if (error == 0)
1432                         soopt_from_kbuf(sopt, &optval, sizeof optval);
1433                 break;
1434         }
1435 done:
1436         lwkt_replymsg(&msg->lmsg, error);
1437 }
1438
1439 /*
1440  * tcp_sendspace and tcp_recvspace are the default send and receive window
1441  * sizes, respectively.  These are obsolescent (this information should
1442  * be set by the route).
1443  *
1444  * Use a default that does not require tcp window scaling to be turned
1445  * on.  Individual programs or the administrator can increase the default.
1446  */
1447 u_long  tcp_sendspace = 57344;  /* largest multiple of PAGE_SIZE < 64k */
1448 SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1449     &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1450 u_long  tcp_recvspace = 57344;  /* largest multiple of PAGE_SIZE < 64k */
1451 SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1452     &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1453
1454 /*
1455  * Attach TCP protocol to socket, allocating internet protocol control
1456  * block, tcp control block, bufer space, and entering LISTEN state
1457  * if to accept connections.
1458  */
1459 static int
1460 tcp_attach(struct socket *so, struct pru_attach_info *ai)
1461 {
1462         struct tcpcb *tp;
1463         struct inpcb *inp;
1464         int error;
1465         int cpu;
1466 #ifdef INET6
1467         int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
1468 #endif
1469
1470         if (so->so_snd.ssb_hiwat == 0 || so->so_rcv.ssb_hiwat == 0) {
1471                 lwkt_gettoken(&so->so_rcv.ssb_token);
1472                 error = soreserve(so, tcp_sendspace, tcp_recvspace,
1473                                   ai->sb_rlimit);
1474                 lwkt_reltoken(&so->so_rcv.ssb_token);
1475                 if (error)
1476                         return (error);
1477         }
1478         atomic_set_int(&so->so_rcv.ssb_flags, SSB_AUTOSIZE);
1479         atomic_set_int(&so->so_snd.ssb_flags, SSB_AUTOSIZE);
1480         cpu = mycpu->gd_cpuid;
1481
1482         /*
1483          * Set the default port for protocol processing. This will likely
1484          * change when we connect.
1485          */
1486         error = in_pcballoc(so, &tcbinfo[cpu]);
1487         if (error)
1488                 return (error);
1489         inp = so->so_pcb;
1490 #ifdef INET6
1491         if (isipv6) {
1492                 inp->inp_vflag |= INP_IPV6;
1493                 inp->in6p_hops = -1;    /* use kernel default */
1494         }
1495         else
1496 #endif
1497         inp->inp_vflag |= INP_IPV4;
1498         tp = tcp_newtcpcb(inp);
1499         if (tp == NULL) {
1500                 /*
1501                  * Make sure the socket is destroyed by the pcbdetach.
1502                  */
1503                 soreference(so);
1504 #ifdef INET6
1505                 if (isipv6)
1506                         in6_pcbdetach(inp);
1507                 else
1508 #endif
1509                 in_pcbdetach(inp);
1510                 sofree(so);     /* from ref above */
1511                 return (ENOBUFS);
1512         }
1513         tp->t_state = TCPS_CLOSED;
1514         return (0);
1515 }
1516
1517 /*
1518  * Initiate (or continue) disconnect.
1519  * If embryonic state, just send reset (once).
1520  * If in ``let data drain'' option and linger null, just drop.
1521  * Otherwise (hard), mark socket disconnecting and drop
1522  * current input data; switch states based on user close, and
1523  * send segment to peer (with FIN).
1524  */
1525 static struct tcpcb *
1526 tcp_disconnect(struct tcpcb *tp)
1527 {
1528         struct socket *so = tp->t_inpcb->inp_socket;
1529
1530         if (tp->t_state < TCPS_ESTABLISHED) {
1531                 tp = tcp_close(tp);
1532         } else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1533                 tp = tcp_drop(tp, 0);
1534         } else {
1535                 lwkt_gettoken(&so->so_rcv.ssb_token);
1536                 soisdisconnecting(so);
1537                 sbflush(&so->so_rcv.sb);
1538                 tp = tcp_usrclosed(tp);
1539                 if (tp)
1540                         tcp_output(tp);
1541                 lwkt_reltoken(&so->so_rcv.ssb_token);
1542         }
1543         return (tp);
1544 }
1545
1546 /*
1547  * User issued close, and wish to trail through shutdown states:
1548  * if never received SYN, just forget it.  If got a SYN from peer,
1549  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1550  * If already got a FIN from peer, then almost done; go to LAST_ACK
1551  * state.  In all other cases, have already sent FIN to peer (e.g.
1552  * after PRU_SHUTDOWN), and just have to play tedious game waiting
1553  * for peer to send FIN or not respond to keep-alives, etc.
1554  * We can let the user exit from the close as soon as the FIN is acked.
1555  */
1556 static struct tcpcb *
1557 tcp_usrclosed(struct tcpcb *tp)
1558 {
1559
1560         switch (tp->t_state) {
1561
1562         case TCPS_CLOSED:
1563         case TCPS_LISTEN:
1564                 tp->t_state = TCPS_CLOSED;
1565                 tp = tcp_close(tp);
1566                 break;
1567
1568         case TCPS_SYN_SENT:
1569         case TCPS_SYN_RECEIVED:
1570                 tp->t_flags |= TF_NEEDFIN;
1571                 break;
1572
1573         case TCPS_ESTABLISHED:
1574                 tp->t_state = TCPS_FIN_WAIT_1;
1575                 break;
1576
1577         case TCPS_CLOSE_WAIT:
1578                 tp->t_state = TCPS_LAST_ACK;
1579                 break;
1580         }
1581         if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
1582                 soisdisconnected(tp->t_inpcb->inp_socket);
1583                 /* To prevent the connection hanging in FIN_WAIT_2 forever. */
1584                 if (tp->t_state == TCPS_FIN_WAIT_2) {
1585                         tcp_callout_reset(tp, tp->tt_2msl, tcp_maxidle,
1586                             tcp_timer_2msl);
1587                 }
1588         }
1589         return (tp);
1590 }