sys/netinet/tcp_usrreq.c

   1 /*-
   2  * Copyright (c) 1982, 1986, 1988, 1993
   3  *      The Regents of the University of California.
   4  * Copyright (c) 2006-2007 Robert N. M. Watson
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 4. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      From: @(#)tcp_usrreq.c  8.2 (Berkeley) 1/3/94
  32  * $FreeBSD$
  33  */
  34
  35 #include "opt_ddb.h"
  36 #include "opt_inet.h"
  37 #include "opt_inet6.h"
  38 #include "opt_tcpdebug.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/systm.h>
  42 #include <sys/malloc.h>
  43 #include <sys/kernel.h>
  44 #include <sys/sysctl.h>
  45 #include <sys/mbuf.h>
  46 #ifdef INET6
  47 #include <sys/domain.h>
  48 #endif /* INET6 */
  49 #include <sys/socket.h>
  50 #include <sys/socketvar.h>
  51 #include <sys/protosw.h>
  52 #include <sys/proc.h>
  53 #include <sys/jail.h>
  54
  55 #ifdef DDB
  56 #include <ddb/ddb.h>
  57 #endif
  58
  59 #include <net/if.h>
  60 #include <net/route.h>
  61
  62 #include <netinet/in.h>
  63 #include <netinet/in_systm.h>
  64 #ifdef INET6
  65 #include <netinet/ip6.h>
  66 #endif
  67 #include <netinet/in_pcb.h>
  68 #ifdef INET6
  69 #include <netinet6/in6_pcb.h>
  70 #endif
  71 #include <netinet/in_var.h>
  72 #include <netinet/ip_var.h>
  73 #ifdef INET6
  74 #include <netinet6/ip6_var.h>
  75 #include <netinet6/scope6_var.h>
  76 #endif
  77 #include <netinet/tcp.h>
  78 #include <netinet/tcp_fsm.h>
  79 #include <netinet/tcp_seq.h>
  80 #include <netinet/tcp_timer.h>
  81 #include <netinet/tcp_var.h>
  82 #include <netinet/tcpip.h>
  83 #ifdef TCPDEBUG
  84 #include <netinet/tcp_debug.h>
  85 #endif
  86
  87 /*
  88  * TCP protocol interface to socket abstraction.
  89  */
  90 static int      tcp_attach(struct socket *);
  91 static int      tcp_connect(struct tcpcb *, struct sockaddr *,
  92                     struct thread *td);
  93 #ifdef INET6
  94 static int      tcp6_connect(struct tcpcb *, struct sockaddr *,
  95                     struct thread *td);
  96 #endif /* INET6 */
  97 static void     tcp_disconnect(struct tcpcb *);
  98 static void     tcp_usrclosed(struct tcpcb *);
  99 static void     tcp_fill_info(struct tcpcb *, struct tcp_info *);
 100
 101 #ifdef TCPDEBUG
 102 #define TCPDEBUG0       int ostate = 0
 103 #define TCPDEBUG1()     ostate = tp ? tp->t_state : 0
 104 #define TCPDEBUG2(req)  if (tp && (so->so_options & SO_DEBUG)) \
 105                                 tcp_trace(TA_USER, ostate, tp, 0, 0, req)
 106 #else
 107 #define TCPDEBUG0
 108 #define TCPDEBUG1()
 109 #define TCPDEBUG2(req)
 110 #endif
 111
 112 /*
 113  * TCP attaches to socket via pru_attach(), reserving space,
 114  * and an internet control block.
 115  */
 116 static int
 117 tcp_usr_attach(struct socket *so, int proto, struct thread *td)
 118 {
 119         struct inpcb *inp;
 120         struct tcpcb *tp = NULL;
 121         int error;
 122         TCPDEBUG0;
 123
 124         inp = sotoinpcb(so);
 125         KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
 126         TCPDEBUG1();
 127
 128         error = tcp_attach(so);
 129         if (error)
 130                 goto out;
 131
 132         if ((so->so_options & SO_LINGER) && so->so_linger == 0)
 133                 so->so_linger = TCP_LINGERTIME;
 134
 135         inp = sotoinpcb(so);
 136         tp = intotcpcb(inp);
 137 out:
 138         TCPDEBUG2(PRU_ATTACH);
 139         return error;
 140 }
 141
 142 /*
 143  * tcp_detach is called when the socket layer loses its final reference
 144  * to the socket, be it a file descriptor reference, a reference from TCP,
 145  * etc.  At this point, there is only one case in which we will keep around
 146  * inpcb state: time wait.
 147  *
 148  * This function can probably be re-absorbed back into tcp_usr_detach() now
 149  * that there is a single detach path.
 150  */
 151 static void
 152 tcp_detach(struct socket *so, struct inpcb *inp)
 153 {
 154         struct tcpcb *tp;
 155 #ifdef INET6
 156         int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
 157 #endif
 158
 159         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 160         INP_LOCK_ASSERT(inp);
 161
 162         KASSERT(so->so_pcb == inp, ("tcp_detach: so_pcb != inp"));
 163         KASSERT(inp->inp_socket == so, ("tcp_detach: inp_socket != so"));
 164
 165         tp = intotcpcb(inp);
 166
 167         if (inp->inp_vflag & INP_TIMEWAIT) {
 168                 /*
 169                  * There are two cases to handle: one in which the time wait
 170                  * state is being discarded (INP_DROPPED), and one in which
 171                  * this connection will remain in timewait.  In the former,
 172                  * it is time to discard all state (except tcptw, which has
 173                  * already been discarded by the timewait close code, which
 174                  * should be further up the call stack somewhere).  In the
 175                  * latter case, we detach from the socket, but leave the pcb
 176                  * present until timewait ends.
 177                  *
 178                  * XXXRW: Would it be cleaner to free the tcptw here?
 179                  */
 180                 if (inp->inp_vflag & INP_DROPPED) {
 181                         KASSERT(tp == NULL, ("tcp_detach: INP_TIMEWAIT && "
 182                             "INP_DROPPED && tp != NULL"));
 183 #ifdef INET6
 184                         if (isipv6) {
 185                                 in6_pcbdetach(inp);
 186                                 in6_pcbfree(inp);
 187                         } else {
 188 #endif
 189                                 in_pcbdetach(inp);
 190                                 in_pcbfree(inp);
 191 #ifdef INET6
 192                         }
 193 #endif
 194                 } else {
 195 #ifdef INET6
 196                         if (isipv6)
 197                                 in6_pcbdetach(inp);
 198                         else
 199 #endif
 200                                 in_pcbdetach(inp);
 201                         INP_UNLOCK(inp);
 202                 }
 203         } else {
 204                 /*
 205                  * If the connection is not in timewait, we consider two
 206                  * two conditions: one in which no further processing is
 207                  * necessary (dropped || embryonic), and one in which TCP is
 208                  * not yet done, but no longer requires the socket, so the
 209                  * pcb will persist for the time being.
 210                  *
 211                  * XXXRW: Does the second case still occur?
 212                  */
 213                 if (inp->inp_vflag & INP_DROPPED ||
 214                     tp->t_state < TCPS_SYN_SENT) {
 215                         tcp_discardcb(tp);
 216 #ifdef INET6
 217                         if (isipv6) {
 218                                 in6_pcbdetach(inp);
 219                                 in6_pcbfree(inp);
 220                         } else {
 221 #endif
 222                                 in_pcbdetach(inp);
 223                                 in_pcbfree(inp);
 224 #ifdef INET6
 225                         }
 226 #endif
 227                 } else {
 228 #ifdef INET6
 229                         if (isipv6)
 230                                 in6_pcbdetach(inp);
 231                         else
 232 #endif
 233                                 in_pcbdetach(inp);
 234                 }
 235         }
 236 }
 237
 238 /*
 239  * pru_detach() detaches the TCP protocol from the socket.
 240  * If the protocol state is non-embryonic, then can't
 241  * do this directly: have to initiate a pru_disconnect(),
 242  * which may finish later; embryonic TCB's can just
 243  * be discarded here.
 244  */
 245 static void
 246 tcp_usr_detach(struct socket *so)
 247 {
 248         struct inpcb *inp;
 249
 250         inp = sotoinpcb(so);
 251         KASSERT(inp != NULL, ("tcp_usr_detach: inp == NULL"));
 252         INP_INFO_WLOCK(&tcbinfo);
 253         INP_LOCK(inp);
 254         KASSERT(inp->inp_socket != NULL,
 255             ("tcp_usr_detach: inp_socket == NULL"));
 256         tcp_detach(so, inp);
 257         INP_INFO_WUNLOCK(&tcbinfo);
 258 }
 259
 260 /*
 261  * Give the socket an address.
 262  */
 263 static int
 264 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 265 {
 266         int error = 0;
 267         struct inpcb *inp;
 268         struct tcpcb *tp = NULL;
 269         struct sockaddr_in *sinp;
 270
 271         sinp = (struct sockaddr_in *)nam;
 272         if (nam->sa_len != sizeof (*sinp))
 273                 return (EINVAL);
 274         /*
 275          * Must check for multicast addresses and disallow binding
 276          * to them.
 277          */
 278         if (sinp->sin_family == AF_INET &&
 279             IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
 280                 return (EAFNOSUPPORT);
 281
 282         TCPDEBUG0;
 283         INP_INFO_WLOCK(&tcbinfo);
 284         inp = sotoinpcb(so);
 285         KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
 286         INP_LOCK(inp);
 287         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 288                 error = EINVAL;
 289                 goto out;
 290         }
 291         tp = intotcpcb(inp);
 292         TCPDEBUG1();
 293         error = in_pcbbind(inp, nam, td->td_ucred);
 294 out:
 295         TCPDEBUG2(PRU_BIND);
 296         INP_UNLOCK(inp);
 297         INP_INFO_WUNLOCK(&tcbinfo);
 298
 299         return (error);
 300 }
 301
 302 #ifdef INET6
 303 static int
 304 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 305 {
 306         int error = 0;
 307         struct inpcb *inp;
 308         struct tcpcb *tp = NULL;
 309         struct sockaddr_in6 *sin6p;
 310
 311         sin6p = (struct sockaddr_in6 *)nam;
 312         if (nam->sa_len != sizeof (*sin6p))
 313                 return (EINVAL);
 314         /*
 315          * Must check for multicast addresses and disallow binding
 316          * to them.
 317          */
 318         if (sin6p->sin6_family == AF_INET6 &&
 319             IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
 320                 return (EAFNOSUPPORT);
 321
 322         TCPDEBUG0;
 323         INP_INFO_WLOCK(&tcbinfo);
 324         inp = sotoinpcb(so);
 325         KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
 326         INP_LOCK(inp);
 327         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 328                 error = EINVAL;
 329                 goto out;
 330         }
 331         tp = intotcpcb(inp);
 332         TCPDEBUG1();
 333         inp->inp_vflag &= ~INP_IPV4;
 334         inp->inp_vflag |= INP_IPV6;
 335         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 336                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
 337                         inp->inp_vflag |= INP_IPV4;
 338                 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
 339                         struct sockaddr_in sin;
 340
 341                         in6_sin6_2_sin(&sin, sin6p);
 342                         inp->inp_vflag |= INP_IPV4;
 343                         inp->inp_vflag &= ~INP_IPV6;
 344                         error = in_pcbbind(inp, (struct sockaddr *)&sin,
 345                             td->td_ucred);
 346                         goto out;
 347                 }
 348         }
 349         error = in6_pcbbind(inp, nam, td->td_ucred);
 350 out:
 351         TCPDEBUG2(PRU_BIND);
 352         INP_UNLOCK(inp);
 353         INP_INFO_WUNLOCK(&tcbinfo);
 354         return (error);
 355 }
 356 #endif /* INET6 */
 357
 358 /*
 359  * Prepare to accept connections.
 360  */
 361 static int
 362 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
 363 {
 364         int error = 0;
 365         struct inpcb *inp;
 366         struct tcpcb *tp = NULL;
 367
 368         TCPDEBUG0;
 369         INP_INFO_WLOCK(&tcbinfo);
 370         inp = sotoinpcb(so);
 371         KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
 372         INP_LOCK(inp);
 373         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 374                 error = EINVAL;
 375                 goto out;
 376         }
 377         tp = intotcpcb(inp);
 378         TCPDEBUG1();
 379         SOCK_LOCK(so);
 380         error = solisten_proto_check(so);
 381         if (error == 0 && inp->inp_lport == 0)
 382                 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
 383         if (error == 0) {
 384                 tp->t_state = TCPS_LISTEN;
 385                 solisten_proto(so, backlog);
 386         }
 387         SOCK_UNLOCK(so);
 388
 389 out:
 390         TCPDEBUG2(PRU_LISTEN);
 391         INP_UNLOCK(inp);
 392         INP_INFO_WUNLOCK(&tcbinfo);
 393         return (error);
 394 }
 395
 396 #ifdef INET6
 397 static int
 398 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
 399 {
 400         int error = 0;
 401         struct inpcb *inp;
 402         struct tcpcb *tp = NULL;
 403
 404         TCPDEBUG0;
 405         INP_INFO_WLOCK(&tcbinfo);
 406         inp = sotoinpcb(so);
 407         KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
 408         INP_LOCK(inp);
 409         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 410                 error = EINVAL;
 411                 goto out;
 412         }
 413         tp = intotcpcb(inp);
 414         TCPDEBUG1();
 415         SOCK_LOCK(so);
 416         error = solisten_proto_check(so);
 417         if (error == 0 && inp->inp_lport == 0) {
 418                 inp->inp_vflag &= ~INP_IPV4;
 419                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
 420                         inp->inp_vflag |= INP_IPV4;
 421                 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
 422         }
 423         if (error == 0) {
 424                 tp->t_state = TCPS_LISTEN;
 425                 solisten_proto(so, backlog);
 426         }
 427         SOCK_UNLOCK(so);
 428
 429 out:
 430         TCPDEBUG2(PRU_LISTEN);
 431         INP_UNLOCK(inp);
 432         INP_INFO_WUNLOCK(&tcbinfo);
 433         return (error);
 434 }
 435 #endif /* INET6 */
 436
 437 /*
 438  * Initiate connection to peer.
 439  * Create a template for use in transmissions on this connection.
 440  * Enter SYN_SENT state, and mark socket as connecting.
 441  * Start keep-alive timer, and seed output sequence space.
 442  * Send initial segment on connection.
 443  */
 444 static int
 445 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 446 {
 447         int error = 0;
 448         struct inpcb *inp;
 449         struct tcpcb *tp = NULL;
 450         struct sockaddr_in *sinp;
 451
 452         sinp = (struct sockaddr_in *)nam;
 453         if (nam->sa_len != sizeof (*sinp))
 454                 return (EINVAL);
 455         /*
 456          * Must disallow TCP ``connections'' to multicast addresses.
 457          */
 458         if (sinp->sin_family == AF_INET
 459             && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
 460                 return (EAFNOSUPPORT);
 461         if (jailed(td->td_ucred))
 462                 prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr);
 463
 464         TCPDEBUG0;
 465         INP_INFO_WLOCK(&tcbinfo);
 466         inp = sotoinpcb(so);
 467         KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
 468         INP_LOCK(inp);
 469         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 470                 error = EINVAL;
 471                 goto out;
 472         }
 473         tp = intotcpcb(inp);
 474         TCPDEBUG1();
 475         if ((error = tcp_connect(tp, nam, td)) != 0)
 476                 goto out;
 477         error = tcp_output(tp);
 478 out:
 479         TCPDEBUG2(PRU_CONNECT);
 480         INP_UNLOCK(inp);
 481         INP_INFO_WUNLOCK(&tcbinfo);
 482         return (error);
 483 }
 484
 485 #ifdef INET6
 486 static int
 487 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 488 {
 489         int error = 0;
 490         struct inpcb *inp;
 491         struct tcpcb *tp = NULL;
 492         struct sockaddr_in6 *sin6p;
 493
 494         TCPDEBUG0;
 495
 496         sin6p = (struct sockaddr_in6 *)nam;
 497         if (nam->sa_len != sizeof (*sin6p))
 498                 return (EINVAL);
 499         /*
 500          * Must disallow TCP ``connections'' to multicast addresses.
 501          */
 502         if (sin6p->sin6_family == AF_INET6
 503             && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
 504                 return (EAFNOSUPPORT);
 505
 506         INP_INFO_WLOCK(&tcbinfo);
 507         inp = sotoinpcb(so);
 508         KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
 509         INP_LOCK(inp);
 510         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 511                 error = EINVAL;
 512                 goto out;
 513         }
 514         tp = intotcpcb(inp);
 515         TCPDEBUG1();
 516         if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
 517                 struct sockaddr_in sin;
 518
 519                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
 520                         error = EINVAL;
 521                         goto out;
 522                 }
 523
 524                 in6_sin6_2_sin(&sin, sin6p);
 525                 inp->inp_vflag |= INP_IPV4;
 526                 inp->inp_vflag &= ~INP_IPV6;
 527                 if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
 528                         goto out;
 529                 error = tcp_output(tp);
 530                 goto out;
 531         }
 532         inp->inp_vflag &= ~INP_IPV4;
 533         inp->inp_vflag |= INP_IPV6;
 534         inp->inp_inc.inc_isipv6 = 1;
 535         if ((error = tcp6_connect(tp, nam, td)) != 0)
 536                 goto out;
 537         error = tcp_output(tp);
 538
 539 out:
 540         TCPDEBUG2(PRU_CONNECT);
 541         INP_UNLOCK(inp);
 542         INP_INFO_WUNLOCK(&tcbinfo);
 543         return (error);
 544 }
 545 #endif /* INET6 */
 546
 547 /*
 548  * Initiate disconnect from peer.
 549  * If connection never passed embryonic stage, just drop;
 550  * else if don't need to let data drain, then can just drop anyways,
 551  * else have to begin TCP shutdown process: mark socket disconnecting,
 552  * drain unread data, state switch to reflect user close, and
 553  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
 554  * when peer sends FIN and acks ours.
 555  *
 556  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
 557  */
 558 static int
 559 tcp_usr_disconnect(struct socket *so)
 560 {
 561         struct inpcb *inp;
 562         struct tcpcb *tp = NULL;
 563         int error = 0;
 564
 565         TCPDEBUG0;
 566         INP_INFO_WLOCK(&tcbinfo);
 567         inp = sotoinpcb(so);
 568         KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
 569         INP_LOCK(inp);
 570         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 571                 error = ECONNRESET;
 572                 goto out;
 573         }
 574         tp = intotcpcb(inp);
 575         TCPDEBUG1();
 576         tcp_disconnect(tp);
 577 out:
 578         TCPDEBUG2(PRU_DISCONNECT);
 579         INP_UNLOCK(inp);
 580         INP_INFO_WUNLOCK(&tcbinfo);
 581         return (error);
 582 }
 583
 584 /*
 585  * Accept a connection.  Essentially all the work is
 586  * done at higher levels; just return the address
 587  * of the peer, storing through addr.
 588  */
 589 static int
 590 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
 591 {
 592         int error = 0;
 593         struct inpcb *inp = NULL;
 594         struct tcpcb *tp = NULL;
 595         struct in_addr addr;
 596         in_port_t port = 0;
 597         TCPDEBUG0;
 598
 599         if (so->so_state & SS_ISDISCONNECTED)
 600                 return (ECONNABORTED);
 601
 602         inp = sotoinpcb(so);
 603         KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
 604         INP_LOCK(inp);
 605         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 606                 error = ECONNABORTED;
 607                 goto out;
 608         }
 609         tp = intotcpcb(inp);
 610         TCPDEBUG1();
 611
 612         /*
 613          * We inline in_getpeeraddr and COMMON_END here, so that we can
 614          * copy the data of interest and defer the malloc until after we
 615          * release the lock.
 616          */
 617         port = inp->inp_fport;
 618         addr = inp->inp_faddr;
 619
 620 out:
 621         TCPDEBUG2(PRU_ACCEPT);
 622         INP_UNLOCK(inp);
 623         if (error == 0)
 624                 *nam = in_sockaddr(port, &addr);
 625         return error;
 626 }
 627
 628 #ifdef INET6
 629 static int
 630 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
 631 {
 632         struct inpcb *inp = NULL;
 633         int error = 0;
 634         struct tcpcb *tp = NULL;
 635         struct in_addr addr;
 636         struct in6_addr addr6;
 637         in_port_t port = 0;
 638         int v4 = 0;
 639         TCPDEBUG0;
 640
 641         if (so->so_state & SS_ISDISCONNECTED)
 642                 return (ECONNABORTED);
 643
 644         inp = sotoinpcb(so);
 645         KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
 646         INP_LOCK(inp);
 647         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 648                 error = ECONNABORTED;
 649                 goto out;
 650         }
 651         tp = intotcpcb(inp);
 652         TCPDEBUG1();
 653
 654         /*
 655          * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
 656          * copy the data of interest and defer the malloc until after we
 657          * release the lock.
 658          */
 659         if (inp->inp_vflag & INP_IPV4) {
 660                 v4 = 1;
 661                 port = inp->inp_fport;
 662                 addr = inp->inp_faddr;
 663         } else {
 664                 port = inp->inp_fport;
 665                 addr6 = inp->in6p_faddr;
 666         }
 667
 668 out:
 669         TCPDEBUG2(PRU_ACCEPT);
 670         INP_UNLOCK(inp);
 671         if (error == 0) {
 672                 if (v4)
 673                         *nam = in6_v4mapsin6_sockaddr(port, &addr);
 674                 else
 675                         *nam = in6_sockaddr(port, &addr6);
 676         }
 677         return error;
 678 }
 679 #endif /* INET6 */
 680
 681 /*
 682  * Mark the connection as being incapable of further output.
 683  */
 684 static int
 685 tcp_usr_shutdown(struct socket *so)
 686 {
 687         int error = 0;
 688         struct inpcb *inp;
 689         struct tcpcb *tp = NULL;
 690
 691         TCPDEBUG0;
 692         INP_INFO_WLOCK(&tcbinfo);
 693         inp = sotoinpcb(so);
 694         KASSERT(inp != NULL, ("inp == NULL"));
 695         INP_LOCK(inp);
 696         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 697                 error = ECONNRESET;
 698                 goto out;
 699         }
 700         tp = intotcpcb(inp);
 701         TCPDEBUG1();
 702         socantsendmore(so);
 703         tcp_usrclosed(tp);
 704         error = tcp_output(tp);
 705
 706 out:
 707         TCPDEBUG2(PRU_SHUTDOWN);
 708         INP_UNLOCK(inp);
 709         INP_INFO_WUNLOCK(&tcbinfo);
 710
 711         return (error);
 712 }
 713
 714 /*
 715  * After a receive, possibly send window update to peer.
 716  */
 717 static int
 718 tcp_usr_rcvd(struct socket *so, int flags)
 719 {
 720         struct inpcb *inp;
 721         struct tcpcb *tp = NULL;
 722         int error = 0;
 723
 724         TCPDEBUG0;
 725         inp = sotoinpcb(so);
 726         KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
 727         INP_LOCK(inp);
 728         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 729                 error = ECONNRESET;
 730                 goto out;
 731         }
 732         tp = intotcpcb(inp);
 733         TCPDEBUG1();
 734         tcp_output(tp);
 735
 736 out:
 737         TCPDEBUG2(PRU_RCVD);
 738         INP_UNLOCK(inp);
 739         return (error);
 740 }
 741
 742 /*
 743  * Do a send by putting data in output queue and updating urgent
 744  * marker if URG set.  Possibly send more data.  Unlike the other
 745  * pru_*() routines, the mbuf chains are our responsibility.  We
 746  * must either enqueue them or free them.  The other pru_* routines
 747  * generally are caller-frees.
 748  */
 749 static int
 750 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
 751     struct sockaddr *nam, struct mbuf *control, struct thread *td)
 752 {
 753         int error = 0;
 754         struct inpcb *inp;
 755         struct tcpcb *tp = NULL;
 756         int headlocked = 0;
 757 #ifdef INET6
 758         int isipv6;
 759 #endif
 760         TCPDEBUG0;
 761
 762         /*
 763          * We require the pcbinfo lock in two cases:
 764          *
 765          * (1) An implied connect is taking place, which can result in
 766          *     binding IPs and ports and hence modification of the pcb hash
 767          *     chains.
 768          *
 769          * (2) PRUS_EOF is set, resulting in explicit close on the send.
 770          */
 771         if ((nam != NULL) || (flags & PRUS_EOF)) {
 772                 INP_INFO_WLOCK(&tcbinfo);
 773                 headlocked = 1;
 774         }
 775         inp = sotoinpcb(so);
 776         KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
 777         INP_LOCK(inp);
 778         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 779                 if (control)
 780                         m_freem(control);
 781                 if (m)
 782                         m_freem(m);
 783                 error = ECONNRESET;
 784                 goto out;
 785         }
 786 #ifdef INET6
 787         isipv6 = nam && nam->sa_family == AF_INET6;
 788 #endif /* INET6 */
 789         tp = intotcpcb(inp);
 790         TCPDEBUG1();
 791         if (control) {
 792                 /* TCP doesn't do control messages (rights, creds, etc) */
 793                 if (control->m_len) {
 794                         m_freem(control);
 795                         if (m)
 796                                 m_freem(m);
 797                         error = EINVAL;
 798                         goto out;
 799                 }
 800                 m_freem(control);       /* empty control, just free it */
 801         }
 802         if (!(flags & PRUS_OOB)) {
 803                 sbappendstream(&so->so_snd, m);
 804                 if (nam && tp->t_state < TCPS_SYN_SENT) {
 805                         /*
 806                          * Do implied connect if not yet connected,
 807                          * initialize window to default value, and
 808                          * initialize maxseg/maxopd using peer's cached
 809                          * MSS.
 810                          */
 811                         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 812 #ifdef INET6
 813                         if (isipv6)
 814                                 error = tcp6_connect(tp, nam, td);
 815                         else
 816 #endif /* INET6 */
 817                         error = tcp_connect(tp, nam, td);
 818                         if (error)
 819                                 goto out;
 820                         tp->snd_wnd = TTCP_CLIENT_SND_WND;
 821                         tcp_mss(tp, -1);
 822                 }
 823                 if (flags & PRUS_EOF) {
 824                         /*
 825                          * Close the send side of the connection after
 826                          * the data is sent.
 827                          */
 828                         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 829                         socantsendmore(so);
 830                         tcp_usrclosed(tp);
 831                 }
 832                 if (headlocked) {
 833                         INP_INFO_WUNLOCK(&tcbinfo);
 834                         headlocked = 0;
 835                 }
 836                 if (tp != NULL) {
 837                         if (flags & PRUS_MORETOCOME)
 838                                 tp->t_flags |= TF_MORETOCOME;
 839                         error = tcp_output(tp);
 840                         if (flags & PRUS_MORETOCOME)
 841                                 tp->t_flags &= ~TF_MORETOCOME;
 842                 }
 843         } else {
 844                 /*
 845                  * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
 846                  */
 847                 SOCKBUF_LOCK(&so->so_snd);
 848                 if (sbspace(&so->so_snd) < -512) {
 849                         SOCKBUF_UNLOCK(&so->so_snd);
 850                         m_freem(m);
 851                         error = ENOBUFS;
 852                         goto out;
 853                 }
 854                 /*
 855                  * According to RFC961 (Assigned Protocols),
 856                  * the urgent pointer points to the last octet
 857                  * of urgent data.  We continue, however,
 858                  * to consider it to indicate the first octet
 859                  * of data past the urgent section.
 860                  * Otherwise, snd_up should be one lower.
 861                  */
 862                 sbappendstream_locked(&so->so_snd, m);
 863                 SOCKBUF_UNLOCK(&so->so_snd);
 864                 if (nam && tp->t_state < TCPS_SYN_SENT) {
 865                         /*
 866                          * Do implied connect if not yet connected,
 867                          * initialize window to default value, and
 868                          * initialize maxseg/maxopd using peer's cached
 869                          * MSS.
 870                          */
 871                         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 872 #ifdef INET6
 873                         if (isipv6)
 874                                 error = tcp6_connect(tp, nam, td);
 875                         else
 876 #endif /* INET6 */
 877                         error = tcp_connect(tp, nam, td);
 878                         if (error)
 879                                 goto out;
 880                         tp->snd_wnd = TTCP_CLIENT_SND_WND;
 881                         tcp_mss(tp, -1);
 882                         INP_INFO_WUNLOCK(&tcbinfo);
 883                         headlocked = 0;
 884                 } else if (nam) {
 885                         INP_INFO_WUNLOCK(&tcbinfo);
 886                         headlocked = 0;
 887                 }
 888                 tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 889                 tp->t_flags |= TF_FORCEDATA;
 890                 error = tcp_output(tp);
 891                 tp->t_flags &= ~TF_FORCEDATA;
 892         }
 893 out:
 894         TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
 895                   ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
 896         INP_UNLOCK(inp);
 897         if (headlocked)
 898                 INP_INFO_WUNLOCK(&tcbinfo);
 899         return (error);
 900 }
 901
 902 /*
 903  * Abort the TCP.  Drop the connection abruptly.
 904  */
 905 static void
 906 tcp_usr_abort(struct socket *so)
 907 {
 908         struct inpcb *inp;
 909         struct tcpcb *tp = NULL;
 910         TCPDEBUG0;
 911
 912         inp = sotoinpcb(so);
 913         KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
 914
 915         INP_INFO_WLOCK(&tcbinfo);
 916         INP_LOCK(inp);
 917         KASSERT(inp->inp_socket != NULL,
 918             ("tcp_usr_abort: inp_socket == NULL"));
 919
 920         /*
 921          * If we still have full TCP state, and we're not dropped, drop.
 922          */
 923         if (!(inp->inp_vflag & INP_TIMEWAIT) &&
 924             !(inp->inp_vflag & INP_DROPPED)) {
 925                 tp = intotcpcb(inp);
 926                 TCPDEBUG1();
 927                 tcp_drop(tp, ECONNABORTED);
 928                 TCPDEBUG2(PRU_ABORT);
 929         }
 930         if (!(inp->inp_vflag & INP_DROPPED)) {
 931                 SOCK_LOCK(so);
 932                 so->so_state |= SS_PROTOREF;
 933                 SOCK_UNLOCK(so);
 934                 inp->inp_vflag |= INP_SOCKREF;
 935         }
 936         INP_UNLOCK(inp);
 937         INP_INFO_WUNLOCK(&tcbinfo);
 938 }
 939
 940 /*
 941  * TCP socket is closed.  Start friendly disconnect.
 942  */
 943 static void
 944 tcp_usr_close(struct socket *so)
 945 {
 946         struct inpcb *inp;
 947         struct tcpcb *tp = NULL;
 948         TCPDEBUG0;
 949
 950         inp = sotoinpcb(so);
 951         KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
 952
 953         INP_INFO_WLOCK(&tcbinfo);
 954         INP_LOCK(inp);
 955         KASSERT(inp->inp_socket != NULL,
 956             ("tcp_usr_close: inp_socket == NULL"));
 957
 958         /*
 959          * If we still have full TCP state, and we're not dropped, initiate
 960          * a disconnect.
 961          */
 962         if (!(inp->inp_vflag & INP_TIMEWAIT) &&
 963             !(inp->inp_vflag & INP_DROPPED)) {
 964                 tp = intotcpcb(inp);
 965                 TCPDEBUG1();
 966                 tcp_disconnect(tp);
 967                 TCPDEBUG2(PRU_CLOSE);
 968         }
 969         if (!(inp->inp_vflag & INP_DROPPED)) {
 970                 SOCK_LOCK(so);
 971                 so->so_state |= SS_PROTOREF;
 972                 SOCK_UNLOCK(so);
 973                 inp->inp_vflag |= INP_SOCKREF;
 974         }
 975         INP_UNLOCK(inp);
 976         INP_INFO_WUNLOCK(&tcbinfo);
 977 }
 978
 979 /*
 980  * Receive out-of-band data.
 981  */
 982 static int
 983 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
 984 {
 985         int error = 0;
 986         struct inpcb *inp;
 987         struct tcpcb *tp = NULL;
 988
 989         TCPDEBUG0;
 990         inp = sotoinpcb(so);
 991         KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
 992         INP_LOCK(inp);
 993         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 994                 error = ECONNRESET;
 995                 goto out;
 996         }
 997         tp = intotcpcb(inp);
 998         TCPDEBUG1();
 999         if ((so->so_oobmark == 0 &&
1000              (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1001             so->so_options & SO_OOBINLINE ||
1002             tp->t_oobflags & TCPOOB_HADDATA) {
1003                 error = EINVAL;
1004                 goto out;
1005         }
1006         if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1007                 error = EWOULDBLOCK;
1008                 goto out;
1009         }
1010         m->m_len = 1;
1011         *mtod(m, caddr_t) = tp->t_iobc;
1012         if ((flags & MSG_PEEK) == 0)
1013                 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1014
1015 out:
1016         TCPDEBUG2(PRU_RCVOOB);
1017         INP_UNLOCK(inp);
1018         return (error);
1019 }
1020
1021 struct pr_usrreqs tcp_usrreqs = {
1022         .pru_abort =            tcp_usr_abort,
1023         .pru_accept =           tcp_usr_accept,
1024         .pru_attach =           tcp_usr_attach,
1025         .pru_bind =             tcp_usr_bind,
1026         .pru_connect =          tcp_usr_connect,
1027         .pru_control =          in_control,
1028         .pru_detach =           tcp_usr_detach,
1029         .pru_disconnect =       tcp_usr_disconnect,
1030         .pru_listen =           tcp_usr_listen,
1031         .pru_peeraddr =         in_getpeeraddr,
1032         .pru_rcvd =             tcp_usr_rcvd,
1033         .pru_rcvoob =           tcp_usr_rcvoob,
1034         .pru_send =             tcp_usr_send,
1035         .pru_shutdown =         tcp_usr_shutdown,
1036         .pru_sockaddr =         in_getsockaddr,
1037         .pru_sosetlabel =       in_pcbsosetlabel,
1038         .pru_close =            tcp_usr_close,
1039 };
1040
1041 #ifdef INET6
1042 struct pr_usrreqs tcp6_usrreqs = {
1043         .pru_abort =            tcp_usr_abort,
1044         .pru_accept =           tcp6_usr_accept,
1045         .pru_attach =           tcp_usr_attach,
1046         .pru_bind =             tcp6_usr_bind,
1047         .pru_connect =          tcp6_usr_connect,
1048         .pru_control =          in6_control,
1049         .pru_detach =           tcp_usr_detach,
1050         .pru_disconnect =       tcp_usr_disconnect,
1051         .pru_listen =           tcp6_usr_listen,
1052         .pru_peeraddr =         in6_mapped_peeraddr,
1053         .pru_rcvd =             tcp_usr_rcvd,
1054         .pru_rcvoob =           tcp_usr_rcvoob,
1055         .pru_send =             tcp_usr_send,
1056         .pru_shutdown =         tcp_usr_shutdown,
1057         .pru_sockaddr =         in6_mapped_sockaddr,
1058         .pru_sosetlabel =       in_pcbsosetlabel,
1059         .pru_close =            tcp_usr_close,
1060 };
1061 #endif /* INET6 */
1062
1063 /*
1064  * Common subroutine to open a TCP connection to remote host specified
1065  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1066  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1067  * to choose a local host address (interface).  If there is an existing
1068  * incarnation of the same connection in TIME-WAIT state and if the remote
1069  * host was sending CC options and if the connection duration was < MSL, then
1070  * truncate the previous TIME-WAIT state and proceed.
1071  * Initialize connection parameters and enter SYN-SENT state.
1072  */
1073 static int
1074 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1075 {
1076         struct inpcb *inp = tp->t_inpcb, *oinp;
1077         struct socket *so = inp->inp_socket;
1078         struct in_addr laddr;
1079         u_short lport;
1080         int error;
1081
1082         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1083         INP_LOCK_ASSERT(inp);
1084
1085         if (inp->inp_lport == 0) {
1086                 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1087                 if (error)
1088                         return error;
1089         }
1090
1091         /*
1092          * Cannot simply call in_pcbconnect, because there might be an
1093          * earlier incarnation of this same connection still in
1094          * TIME_WAIT state, creating an ADDRINUSE error.
1095          */
1096         laddr = inp->inp_laddr;
1097         lport = inp->inp_lport;
1098         error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1099             &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1100         if (error && oinp == NULL)
1101                 return error;
1102         if (oinp)
1103                 return EADDRINUSE;
1104         inp->inp_laddr = laddr;
1105         in_pcbrehash(inp);
1106
1107         /*
1108          * Compute window scaling to request:
1109          * Scale to fit into sweet spot.  See tcp_syncache.c.
1110          * XXX: This should move to tcp_output().
1111          * XXX: This should be based on the actual MSS.
1112          */
1113         while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1114             (0x1 << tp->request_r_scale) < tcp_minmss)
1115                 tp->request_r_scale++;
1116
1117         soisconnecting(so);
1118         tcpstat.tcps_connattempt++;
1119         tp->t_state = TCPS_SYN_SENT;
1120         tcp_timer_activate(tp, TT_KEEP, tcp_keepinit);
1121         tp->iss = tcp_new_isn(tp);
1122         tp->t_bw_rtseq = tp->iss;
1123         tcp_sendseqinit(tp);
1124
1125         return 0;
1126 }
1127
1128 #ifdef INET6
1129 static int
1130 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1131 {
1132         struct inpcb *inp = tp->t_inpcb, *oinp;
1133         struct socket *so = inp->inp_socket;
1134         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
1135         struct in6_addr *addr6;
1136         int error;
1137
1138         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1139         INP_LOCK_ASSERT(inp);
1140
1141         if (inp->inp_lport == 0) {
1142                 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1143                 if (error)
1144                         return error;
1145         }
1146
1147         /*
1148          * Cannot simply call in_pcbconnect, because there might be an
1149          * earlier incarnation of this same connection still in
1150          * TIME_WAIT state, creating an ADDRINUSE error.
1151          * in6_pcbladdr() also handles scope zone IDs.
1152          */
1153         error = in6_pcbladdr(inp, nam, &addr6);
1154         if (error)
1155                 return error;
1156         oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
1157                                   &sin6->sin6_addr, sin6->sin6_port,
1158                                   IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
1159                                   ? addr6
1160                                   : &inp->in6p_laddr,
1161                                   inp->inp_lport,  0, NULL);
1162         if (oinp)
1163                 return EADDRINUSE;
1164         if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
1165                 inp->in6p_laddr = *addr6;
1166         inp->in6p_faddr = sin6->sin6_addr;
1167         inp->inp_fport = sin6->sin6_port;
1168         /* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
1169         inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
1170         if (inp->in6p_flags & IN6P_AUTOFLOWLABEL)
1171                 inp->in6p_flowinfo |=
1172                     (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
1173         in_pcbrehash(inp);
1174
1175         /* Compute window scaling to request.  */
1176         while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1177             (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
1178                 tp->request_r_scale++;
1179
1180         soisconnecting(so);
1181         tcpstat.tcps_connattempt++;
1182         tp->t_state = TCPS_SYN_SENT;
1183         tcp_timer_activate(tp, TT_KEEP, tcp_keepinit);
1184         tp->iss = tcp_new_isn(tp);
1185         tp->t_bw_rtseq = tp->iss;
1186         tcp_sendseqinit(tp);
1187
1188         return 0;
1189 }
1190 #endif /* INET6 */
1191
1192 /*
1193  * Export TCP internal state information via a struct tcp_info, based on the
1194  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1195  * (TCP state machine, etc).  We export all information using FreeBSD-native
1196  * constants -- for example, the numeric values for tcpi_state will differ
1197  * from Linux.
1198  */
1199 static void
1200 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1201 {
1202
1203         INP_LOCK_ASSERT(tp->t_inpcb);
1204         bzero(ti, sizeof(*ti));
1205
1206         ti->tcpi_state = tp->t_state;
1207         if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1208                 ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1209         if (tp->t_flags & TF_SACK_PERMIT)
1210                 ti->tcpi_options |= TCPI_OPT_SACK;
1211         if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1212                 ti->tcpi_options |= TCPI_OPT_WSCALE;
1213                 ti->tcpi_snd_wscale = tp->snd_scale;
1214                 ti->tcpi_rcv_wscale = tp->rcv_scale;
1215         }
1216
1217         ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1218         ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1219
1220         ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1221         ti->tcpi_snd_cwnd = tp->snd_cwnd;
1222
1223         /*
1224          * FreeBSD-specific extension fields for tcp_info.
1225          */
1226         ti->tcpi_rcv_space = tp->rcv_wnd;
1227         ti->tcpi_snd_wnd = tp->snd_wnd;
1228         ti->tcpi_snd_bwnd = tp->snd_bwnd;
1229 }
1230
1231 /*
1232  * The new sockopt interface makes it possible for us to block in the
1233  * copyin/out step (if we take a page fault).  Taking a page fault at
1234  * splnet() is probably a Bad Thing.  (Since sockets and pcbs both now
1235  * use TSM, there probably isn't any need for this function to run at
1236  * splnet() any more.  This needs more examination.)
1237  *
1238  * XXXRW: The locking here is wrong; we may take a page fault while holding
1239  * the inpcb lock.
1240  */
1241 int
1242 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1243 {
1244         int     error, opt, optval;
1245         struct  inpcb *inp;
1246         struct  tcpcb *tp;
1247         struct  tcp_info ti;
1248
1249         error = 0;
1250         inp = sotoinpcb(so);
1251         KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1252         INP_LOCK(inp);
1253         if (sopt->sopt_level != IPPROTO_TCP) {
1254                 INP_UNLOCK(inp);
1255 #ifdef INET6
1256                 if (INP_CHECK_SOCKAF(so, AF_INET6))
1257                         error = ip6_ctloutput(so, sopt);
1258                 else
1259 #endif /* INET6 */
1260                 error = ip_ctloutput(so, sopt);
1261                 return (error);
1262         }
1263         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
1264                 error = ECONNRESET;
1265                 goto out;
1266         }
1267         tp = intotcpcb(inp);
1268
1269         switch (sopt->sopt_dir) {
1270         case SOPT_SET:
1271                 switch (sopt->sopt_name) {
1272 #ifdef TCP_SIGNATURE
1273                 case TCP_MD5SIG:
1274                         error = sooptcopyin(sopt, &optval, sizeof optval,
1275                                             sizeof optval);
1276                         if (error)
1277                                 break;
1278
1279                         if (optval > 0)
1280                                 tp->t_flags |= TF_SIGNATURE;
1281                         else
1282                                 tp->t_flags &= ~TF_SIGNATURE;
1283                         break;
1284 #endif /* TCP_SIGNATURE */
1285                 case TCP_NODELAY:
1286                 case TCP_NOOPT:
1287                         error = sooptcopyin(sopt, &optval, sizeof optval,
1288                                             sizeof optval);
1289                         if (error)
1290                                 break;
1291
1292                         switch (sopt->sopt_name) {
1293                         case TCP_NODELAY:
1294                                 opt = TF_NODELAY;
1295                                 break;
1296                         case TCP_NOOPT:
1297                                 opt = TF_NOOPT;
1298                                 break;
1299                         default:
1300                                 opt = 0; /* dead code to fool gcc */
1301                                 break;
1302                         }
1303
1304                         if (optval)
1305                                 tp->t_flags |= opt;
1306                         else
1307                                 tp->t_flags &= ~opt;
1308                         break;
1309
1310                 case TCP_NOPUSH:
1311                         error = sooptcopyin(sopt, &optval, sizeof optval,
1312                                             sizeof optval);
1313                         if (error)
1314                                 break;
1315
1316                         if (optval)
1317                                 tp->t_flags |= TF_NOPUSH;
1318                         else {
1319                                 tp->t_flags &= ~TF_NOPUSH;
1320                                 error = tcp_output(tp);
1321                         }
1322                         break;
1323
1324                 case TCP_MAXSEG:
1325                         error = sooptcopyin(sopt, &optval, sizeof optval,
1326                                             sizeof optval);
1327                         if (error)
1328                                 break;
1329
1330                         if (optval > 0 && optval <= tp->t_maxseg &&
1331                             optval + 40 >= tcp_minmss)
1332                                 tp->t_maxseg = optval;
1333                         else
1334                                 error = EINVAL;
1335                         break;
1336
1337                 case TCP_INFO:
1338                         error = EINVAL;
1339                         break;
1340
1341                 default:
1342                         error = ENOPROTOOPT;
1343                         break;
1344                 }
1345                 break;
1346
1347         case SOPT_GET:
1348                 switch (sopt->sopt_name) {
1349 #ifdef TCP_SIGNATURE
1350                 case TCP_MD5SIG:
1351                         optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1352                         error = sooptcopyout(sopt, &optval, sizeof optval);
1353                         break;
1354 #endif
1355                 case TCP_NODELAY:
1356                         optval = tp->t_flags & TF_NODELAY;
1357                         error = sooptcopyout(sopt, &optval, sizeof optval);
1358                         break;
1359                 case TCP_MAXSEG:
1360                         optval = tp->t_maxseg;
1361                         error = sooptcopyout(sopt, &optval, sizeof optval);
1362                         break;
1363                 case TCP_NOOPT:
1364                         optval = tp->t_flags & TF_NOOPT;
1365                         error = sooptcopyout(sopt, &optval, sizeof optval);
1366                         break;
1367                 case TCP_NOPUSH:
1368                         optval = tp->t_flags & TF_NOPUSH;
1369                         error = sooptcopyout(sopt, &optval, sizeof optval);
1370                         break;
1371                 case TCP_INFO:
1372                         tcp_fill_info(tp, &ti);
1373                         error = sooptcopyout(sopt, &ti, sizeof ti);
1374                         break;
1375                 default:
1376                         error = ENOPROTOOPT;
1377                         break;
1378                 }
1379                 break;
1380         }
1381 out:
1382         INP_UNLOCK(inp);
1383         return (error);
1384 }
1385
1386 /*
1387  * tcp_sendspace and tcp_recvspace are the default send and receive window
1388  * sizes, respectively.  These are obsolescent (this information should
1389  * be set by the route).
1390  */
1391 u_long  tcp_sendspace = 1024*32;
1392 SYSCTL_ULONG(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1393     &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1394 u_long  tcp_recvspace = 1024*64;
1395 SYSCTL_ULONG(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1396     &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1397
1398 /*
1399  * Attach TCP protocol to socket, allocating
1400  * internet protocol control block, tcp control block,
1401  * bufer space, and entering LISTEN state if to accept connections.
1402  */
1403 static int
1404 tcp_attach(struct socket *so)
1405 {
1406         struct tcpcb *tp;
1407         struct inpcb *inp;
1408         int error;
1409 #ifdef INET6
1410         int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
1411 #endif
1412
1413         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1414                 error = soreserve(so, tcp_sendspace, tcp_recvspace);
1415                 if (error)
1416                         return (error);
1417         }
1418         so->so_rcv.sb_flags |= SB_AUTOSIZE;
1419         so->so_snd.sb_flags |= SB_AUTOSIZE;
1420         INP_INFO_WLOCK(&tcbinfo);
1421         error = in_pcballoc(so, &tcbinfo);
1422         if (error) {
1423                 INP_INFO_WUNLOCK(&tcbinfo);
1424                 return (error);
1425         }
1426         inp = sotoinpcb(so);
1427 #ifdef INET6
1428         if (isipv6) {
1429                 inp->inp_vflag |= INP_IPV6;
1430                 inp->in6p_hops = -1;    /* use kernel default */
1431         }
1432         else
1433 #endif
1434         inp->inp_vflag |= INP_IPV4;
1435         tp = tcp_newtcpcb(inp);
1436         if (tp == NULL) {
1437 #ifdef INET6
1438                 if (isipv6) {
1439                         in6_pcbdetach(inp);
1440                         in6_pcbfree(inp);
1441                 } else {
1442 #endif
1443                         in_pcbdetach(inp);
1444                         in_pcbfree(inp);
1445 #ifdef INET6
1446                 }
1447 #endif
1448                 INP_INFO_WUNLOCK(&tcbinfo);
1449                 return (ENOBUFS);
1450         }
1451         tp->t_state = TCPS_CLOSED;
1452         INP_UNLOCK(inp);
1453         INP_INFO_WUNLOCK(&tcbinfo);
1454         return (0);
1455 }
1456
1457 /*
1458  * Initiate (or continue) disconnect.
1459  * If embryonic state, just send reset (once).
1460  * If in ``let data drain'' option and linger null, just drop.
1461  * Otherwise (hard), mark socket disconnecting and drop
1462  * current input data; switch states based on user close, and
1463  * send segment to peer (with FIN).
1464  */
1465 static void
1466 tcp_disconnect(struct tcpcb *tp)
1467 {
1468         struct inpcb *inp = tp->t_inpcb;
1469         struct socket *so = inp->inp_socket;
1470
1471         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1472         INP_LOCK_ASSERT(inp);
1473
1474         /*
1475          * Neither tcp_close() nor tcp_drop() should return NULL, as the
1476          * socket is still open.
1477          */
1478         if (tp->t_state < TCPS_ESTABLISHED) {
1479                 tp = tcp_close(tp);
1480                 KASSERT(tp != NULL,
1481                     ("tcp_disconnect: tcp_close() returned NULL"));
1482         } else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1483                 tp = tcp_drop(tp, 0);
1484                 KASSERT(tp != NULL,
1485                     ("tcp_disconnect: tcp_drop() returned NULL"));
1486         } else {
1487                 soisdisconnecting(so);
1488                 sbflush(&so->so_rcv);
1489                 tcp_usrclosed(tp);
1490                 if (!(inp->inp_vflag & INP_DROPPED))
1491                         tcp_output(tp);
1492         }
1493 }
1494
1495 /*
1496  * User issued close, and wish to trail through shutdown states:
1497  * if never received SYN, just forget it.  If got a SYN from peer,
1498  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1499  * If already got a FIN from peer, then almost done; go to LAST_ACK
1500  * state.  In all other cases, have already sent FIN to peer (e.g.
1501  * after PRU_SHUTDOWN), and just have to play tedious game waiting
1502  * for peer to send FIN or not respond to keep-alives, etc.
1503  * We can let the user exit from the close as soon as the FIN is acked.
1504  */
1505 static void
1506 tcp_usrclosed(struct tcpcb *tp)
1507 {
1508
1509         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1510         INP_LOCK_ASSERT(tp->t_inpcb);
1511
1512         switch (tp->t_state) {
1513         case TCPS_CLOSED:
1514         case TCPS_LISTEN:
1515                 tp->t_state = TCPS_CLOSED;
1516                 tp = tcp_close(tp);
1517                 /*
1518                  * tcp_close() should never return NULL here as the socket is
1519                  * still open.
1520                  */
1521                 KASSERT(tp != NULL,
1522                     ("tcp_usrclosed: tcp_close() returned NULL"));
1523                 break;
1524
1525         case TCPS_SYN_SENT:
1526         case TCPS_SYN_RECEIVED:
1527                 tp->t_flags |= TF_NEEDFIN;
1528                 break;
1529
1530         case TCPS_ESTABLISHED:
1531                 tp->t_state = TCPS_FIN_WAIT_1;
1532                 break;
1533
1534         case TCPS_CLOSE_WAIT:
1535                 tp->t_state = TCPS_LAST_ACK;
1536                 break;
1537         }
1538         if (tp->t_state >= TCPS_FIN_WAIT_2) {
1539                 soisdisconnected(tp->t_inpcb->inp_socket);
1540                 /* Prevent the connection hanging in FIN_WAIT_2 forever. */
1541                 if (tp->t_state == TCPS_FIN_WAIT_2) {
1542                         int timeout;
1543
1544                         timeout = (tcp_fast_finwait2_recycle) ?
1545                             tcp_finwait2_timeout : tcp_maxidle;
1546                         tcp_timer_activate(tp, TT_2MSL, timeout);
1547                 }
1548         }
1549 }
1550
1551 #ifdef DDB
1552 static void
1553 db_print_indent(int indent)
1554 {
1555         int i;
1556
1557         for (i = 0; i < indent; i++)
1558                 db_printf(" ");
1559 }
1560
1561 static void
1562 db_print_tstate(int t_state)
1563 {
1564
1565         switch (t_state) {
1566         case TCPS_CLOSED:
1567                 db_printf("TCPS_CLOSED");
1568                 return;
1569
1570         case TCPS_LISTEN:
1571                 db_printf("TCPS_LISTEN");
1572                 return;
1573
1574         case TCPS_SYN_SENT:
1575                 db_printf("TCPS_SYN_SENT");
1576                 return;
1577
1578         case TCPS_SYN_RECEIVED:
1579                 db_printf("TCPS_SYN_RECEIVED");
1580                 return;
1581
1582         case TCPS_ESTABLISHED:
1583                 db_printf("TCPS_ESTABLISHED");
1584                 return;
1585
1586         case TCPS_CLOSE_WAIT:
1587                 db_printf("TCPS_CLOSE_WAIT");
1588                 return;
1589
1590         case TCPS_FIN_WAIT_1:
1591                 db_printf("TCPS_FIN_WAIT_1");
1592                 return;
1593
1594         case TCPS_CLOSING:
1595                 db_printf("TCPS_CLOSING");
1596                 return;
1597
1598         case TCPS_LAST_ACK:
1599                 db_printf("TCPS_LAST_ACK");
1600                 return;
1601
1602         case TCPS_FIN_WAIT_2:
1603                 db_printf("TCPS_FIN_WAIT_2");
1604                 return;
1605
1606         case TCPS_TIME_WAIT:
1607                 db_printf("TCPS_TIME_WAIT");
1608                 return;
1609
1610         default:
1611                 db_printf("unknown");
1612                 return;
1613         }
1614 }
1615
1616 static void
1617 db_print_tflags(u_int t_flags)
1618 {
1619         int comma;
1620
1621         comma = 0;
1622         if (t_flags & TF_ACKNOW) {
1623                 db_printf("%sTF_ACKNOW", comma ? ", " : "");
1624                 comma = 1;
1625         }
1626         if (t_flags & TF_DELACK) {
1627                 db_printf("%sTF_DELACK", comma ? ", " : "");
1628                 comma = 1;
1629         }
1630         if (t_flags & TF_NODELAY) {
1631                 db_printf("%sTF_NODELAY", comma ? ", " : "");
1632                 comma = 1;
1633         }
1634         if (t_flags & TF_NOOPT) {
1635                 db_printf("%sTF_NOOPT", comma ? ", " : "");
1636                 comma = 1;
1637         }
1638         if (t_flags & TF_SENTFIN) {
1639                 db_printf("%sTF_SENTFIN", comma ? ", " : "");
1640                 comma = 1;
1641         }
1642         if (t_flags & TF_REQ_SCALE) {
1643                 db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
1644                 comma = 1;
1645         }
1646         if (t_flags & TF_RCVD_SCALE) {
1647                 db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
1648                 comma = 1;
1649         }
1650         if (t_flags & TF_REQ_TSTMP) {
1651                 db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
1652                 comma = 1;
1653         }
1654         if (t_flags & TF_RCVD_TSTMP) {
1655                 db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
1656                 comma = 1;
1657         }
1658         if (t_flags & TF_SACK_PERMIT) {
1659                 db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
1660                 comma = 1;
1661         }
1662         if (t_flags & TF_NEEDSYN) {
1663                 db_printf("%sTF_NEEDSYN", comma ? ", " : "");
1664                 comma = 1;
1665         }
1666         if (t_flags & TF_NEEDFIN) {
1667                 db_printf("%sTF_NEEDFIN", comma ? ", " : "");
1668                 comma = 1;
1669         }
1670         if (t_flags & TF_NOPUSH) {
1671                 db_printf("%sTF_NOPUSH", comma ? ", " : "");
1672                 comma = 1;
1673         }
1674         if (t_flags & TF_NOPUSH) {
1675                 db_printf("%sTF_NOPUSH", comma ? ", " : "");
1676                 comma = 1;
1677         }
1678         if (t_flags & TF_MORETOCOME) {
1679                 db_printf("%sTF_MORETOCOME", comma ? ", " : "");
1680                 comma = 1;
1681         }
1682         if (t_flags & TF_LQ_OVERFLOW) {
1683                 db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
1684                 comma = 1;
1685         }
1686         if (t_flags & TF_LASTIDLE) {
1687                 db_printf("%sTF_LASTIDLE", comma ? ", " : "");
1688                 comma = 1;
1689         }
1690         if (t_flags & TF_RXWIN0SENT) {
1691                 db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
1692                 comma = 1;
1693         }
1694         if (t_flags & TF_FASTRECOVERY) {
1695                 db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
1696                 comma = 1;
1697         }
1698         if (t_flags & TF_WASFRECOVERY) {
1699                 db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
1700                 comma = 1;
1701         }
1702         if (t_flags & TF_SIGNATURE) {
1703                 db_printf("%sTF_SIGNATURE", comma ? ", " : "");
1704                 comma = 1;
1705         }
1706         if (t_flags & TF_FORCEDATA) {
1707                 db_printf("%sTF_FORCEDATA", comma ? ", " : "");
1708                 comma = 1;
1709         }
1710         if (t_flags & TF_TSO) {
1711                 db_printf("%sTF_TSO", comma ? ", " : "");
1712                 comma = 1;
1713         }
1714 }
1715
1716 static void
1717 db_print_toobflags(char t_oobflags)
1718 {
1719         int comma;
1720
1721         comma = 0;
1722         if (t_oobflags & TCPOOB_HAVEDATA) {
1723                 db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
1724                 comma = 1;
1725         }
1726         if (t_oobflags & TCPOOB_HADDATA) {
1727                 db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
1728                 comma = 1;
1729         }
1730 }
1731
1732 static void
1733 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
1734 {
1735
1736         db_print_indent(indent);
1737         db_printf("%s at %p\n", name, tp);
1738
1739         indent += 2;
1740
1741         db_print_indent(indent);
1742         db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
1743            LIST_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
1744
1745         db_print_indent(indent);
1746         db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
1747             &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
1748
1749         db_print_indent(indent);
1750         db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
1751             &tp->t_timers->tt_delack, tp->t_inpcb);
1752
1753         db_print_indent(indent);
1754         db_printf("t_state: %d (", tp->t_state);
1755         db_print_tstate(tp->t_state);
1756         db_printf(")\n");
1757
1758         db_print_indent(indent);
1759         db_printf("t_flags: 0x%x (", tp->t_flags);
1760         db_print_tflags(tp->t_flags);
1761         db_printf(")\n");
1762
1763         db_print_indent(indent);
1764         db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
1765             tp->snd_una, tp->snd_max, tp->snd_nxt);
1766
1767         db_print_indent(indent);
1768         db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
1769            tp->snd_up, tp->snd_wl1, tp->snd_wl2);
1770
1771         db_print_indent(indent);
1772         db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
1773             tp->iss, tp->irs, tp->rcv_nxt);
1774
1775         db_print_indent(indent);
1776         db_printf("rcv_adv: 0x%08x   rcv_wnd: %lu   rcv_up: 0x%08x\n",
1777             tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
1778
1779         db_print_indent(indent);
1780         db_printf("snd_wnd: %lu   snd_cwnd: %lu   snd_bwnd: %lu\n",
1781            tp->snd_wnd, tp->snd_cwnd, tp->snd_bwnd);
1782
1783         db_print_indent(indent);
1784         db_printf("snd_ssthresh: %lu   snd_bandwidth: %lu   snd_recover: "
1785             "0x%08x\n", tp->snd_ssthresh, tp->snd_bandwidth,
1786             tp->snd_recover);
1787
1788         db_print_indent(indent);
1789         db_printf("t_maxopd: %u   t_rcvtime: %lu   t_startime: %lu\n",
1790             tp->t_maxopd, tp->t_rcvtime, tp->t_starttime);
1791
1792         db_print_indent(indent);
1793         db_printf("t_rttime: %d   t_rtsq: 0x%08x   t_bw_rtttime: %d\n",
1794             tp->t_rtttime, tp->t_rtseq, tp->t_bw_rtttime);
1795
1796         db_print_indent(indent);
1797         db_printf("t_bw_rtseq: 0x%08x   t_rxtcur: %d   t_maxseg: %u   "
1798             "t_srtt: %d\n", tp->t_bw_rtseq, tp->t_rxtcur, tp->t_maxseg,
1799             tp->t_srtt);
1800
1801         db_print_indent(indent);
1802         db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
1803             "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
1804             tp->t_rttbest);
1805
1806         db_print_indent(indent);
1807         db_printf("t_rttupdated: %lu   max_sndwnd: %lu   t_softerror: %d\n",
1808             tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
1809
1810         db_print_indent(indent);
1811         db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
1812         db_print_toobflags(tp->t_oobflags);
1813         db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
1814
1815         db_print_indent(indent);
1816         db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
1817             tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
1818
1819         db_print_indent(indent);
1820         db_printf("ts_recent: %u   ts_recent_age: %lu\n",
1821             tp->ts_recent, tp->ts_recent_age);
1822
1823         db_print_indent(indent);
1824         db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
1825             "%lu\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
1826
1827         db_print_indent(indent);
1828         db_printf("snd_ssthresh_prev: %lu   snd_recover_prev: 0x%08x   "
1829             "t_badrxtwin: %lu\n", tp->snd_ssthresh_prev,
1830             tp->snd_recover_prev, tp->t_badrxtwin);
1831
1832         db_print_indent(indent);
1833         db_printf("snd_numholes: %d  snd_holes first: %p\n",
1834             tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
1835
1836         db_print_indent(indent);
1837         db_printf("snd_fack: 0x%08x   rcv_numsacks: %d   sack_newdata: "
1838             "0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
1839
1840         /* Skip sackblks, sackhint. */
1841
1842         db_print_indent(indent);
1843         db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
1844             tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
1845 }
1846
1847 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
1848 {
1849         struct tcpcb *tp;
1850
1851         if (!have_addr) {
1852                 db_printf("usage: show tcpcb <addr>\n");
1853                 return;
1854         }
1855         tp = (struct tcpcb *)addr;
1856
1857         db_print_tcpcb(tp, "tcpcb", 0);
1858 }
1859 #endif