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  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include "opt_ddb.h"
  38 #include "opt_inet.h"
  39 #include "opt_inet6.h"
  40 #include "opt_tcpdebug.h"
  41
  42 #include <sys/param.h>
  43 #include <sys/systm.h>
  44 #include <sys/malloc.h>
  45 #include <sys/kernel.h>
  46 #include <sys/sysctl.h>
  47 #include <sys/mbuf.h>
  48 #ifdef INET6
  49 #include <sys/domain.h>
  50 #endif /* INET6 */
  51 #include <sys/socket.h>
  52 #include <sys/socketvar.h>
  53 #include <sys/protosw.h>
  54 #include <sys/proc.h>
  55 #include <sys/jail.h>
  56
  57 #ifdef DDB
  58 #include <ddb/ddb.h>
  59 #endif
  60
  61 #include <net/if.h>
  62 #include <net/route.h>
  63
  64 #include <netinet/in.h>
  65 #include <netinet/in_systm.h>
  66 #ifdef INET6
  67 #include <netinet/ip6.h>
  68 #endif
  69 #include <netinet/in_pcb.h>
  70 #ifdef INET6
  71 #include <netinet6/in6_pcb.h>
  72 #endif
  73 #include <netinet/in_var.h>
  74 #include <netinet/ip_var.h>
  75 #ifdef INET6
  76 #include <netinet6/ip6_var.h>
  77 #include <netinet6/scope6_var.h>
  78 #endif
  79 #include <netinet/tcp.h>
  80 #include <netinet/tcp_fsm.h>
  81 #include <netinet/tcp_seq.h>
  82 #include <netinet/tcp_timer.h>
  83 #include <netinet/tcp_var.h>
  84 #include <netinet/tcpip.h>
  85 #ifdef TCPDEBUG
  86 #include <netinet/tcp_debug.h>
  87 #endif
  88
  89 /*
  90  * TCP protocol interface to socket abstraction.
  91  */
  92 static int      tcp_attach(struct socket *);
  93 static int      tcp_connect(struct tcpcb *, struct sockaddr *,
  94                     struct thread *td);
  95 #ifdef INET6
  96 static int      tcp6_connect(struct tcpcb *, struct sockaddr *,
  97                     struct thread *td);
  98 #endif /* INET6 */
  99 static void     tcp_disconnect(struct tcpcb *);
 100 static void     tcp_usrclosed(struct tcpcb *);
 101 static void     tcp_fill_info(struct tcpcb *, struct tcp_info *);
 102
 103 #ifdef TCPDEBUG
 104 #define TCPDEBUG0       int ostate = 0
 105 #define TCPDEBUG1()     ostate = tp ? tp->t_state : 0
 106 #define TCPDEBUG2(req)  if (tp && (so->so_options & SO_DEBUG)) \
 107                                 tcp_trace(TA_USER, ostate, tp, 0, 0, req)
 108 #else
 109 #define TCPDEBUG0
 110 #define TCPDEBUG1()
 111 #define TCPDEBUG2(req)
 112 #endif
 113
 114 /*
 115  * TCP attaches to socket via pru_attach(), reserving space,
 116  * and an internet control block.
 117  */
 118 static int
 119 tcp_usr_attach(struct socket *so, int proto, struct thread *td)
 120 {
 121         struct inpcb *inp;
 122         struct tcpcb *tp = NULL;
 123         int error;
 124         TCPDEBUG0;
 125
 126         inp = sotoinpcb(so);
 127         KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
 128         TCPDEBUG1();
 129
 130         error = tcp_attach(so);
 131         if (error)
 132                 goto out;
 133
 134         if ((so->so_options & SO_LINGER) && so->so_linger == 0)
 135                 so->so_linger = TCP_LINGERTIME;
 136
 137         inp = sotoinpcb(so);
 138         tp = intotcpcb(inp);
 139 out:
 140         TCPDEBUG2(PRU_ATTACH);
 141         return error;
 142 }
 143
 144 /*
 145  * tcp_detach is called when the socket layer loses its final reference
 146  * to the socket, be it a file descriptor reference, a reference from TCP,
 147  * etc.  At this point, there is only one case in which we will keep around
 148  * inpcb state: time wait.
 149  *
 150  * This function can probably be re-absorbed back into tcp_usr_detach() now
 151  * that there is a single detach path.
 152  */
 153 static void
 154 tcp_detach(struct socket *so, struct inpcb *inp)
 155 {
 156         struct tcpcb *tp;
 157 #ifdef INET6
 158         int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
 159 #endif
 160
 161         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 162         INP_LOCK_ASSERT(inp);
 163
 164         KASSERT(so->so_pcb == inp, ("tcp_detach: so_pcb != inp"));
 165         KASSERT(inp->inp_socket == so, ("tcp_detach: inp_socket != so"));
 166
 167         tp = intotcpcb(inp);
 168
 169         if (inp->inp_vflag & INP_TIMEWAIT) {
 170                 /*
 171                  * There are two cases to handle: one in which the time wait
 172                  * state is being discarded (INP_DROPPED), and one in which
 173                  * this connection will remain in timewait.  In the former,
 174                  * it is time to discard all state (except tcptw, which has
 175                  * already been discarded by the timewait close code, which
 176                  * should be further up the call stack somewhere).  In the
 177                  * latter case, we detach from the socket, but leave the pcb
 178                  * present until timewait ends.
 179                  *
 180                  * XXXRW: Would it be cleaner to free the tcptw here?
 181                  */
 182                 if (inp->inp_vflag & INP_DROPPED) {
 183                         KASSERT(tp == NULL, ("tcp_detach: INP_TIMEWAIT && "
 184                             "INP_DROPPED && tp != NULL"));
 185 #ifdef INET6
 186                         if (isipv6) {
 187                                 in6_pcbdetach(inp);
 188                                 in6_pcbfree(inp);
 189                         } else {
 190 #endif
 191                                 in_pcbdetach(inp);
 192                                 in_pcbfree(inp);
 193 #ifdef INET6
 194                         }
 195 #endif
 196                 } else {
 197 #ifdef INET6
 198                         if (isipv6)
 199                                 in6_pcbdetach(inp);
 200                         else
 201 #endif
 202                                 in_pcbdetach(inp);
 203                         INP_UNLOCK(inp);
 204                 }
 205         } else {
 206                 /*
 207                  * If the connection is not in timewait, we consider two
 208                  * two conditions: one in which no further processing is
 209                  * necessary (dropped || embryonic), and one in which TCP is
 210                  * not yet done, but no longer requires the socket, so the
 211                  * pcb will persist for the time being.
 212                  *
 213                  * XXXRW: Does the second case still occur?
 214                  */
 215                 if (inp->inp_vflag & INP_DROPPED ||
 216                     tp->t_state < TCPS_SYN_SENT) {
 217                         tcp_discardcb(tp);
 218 #ifdef INET6
 219                         if (isipv6) {
 220                                 in6_pcbdetach(inp);
 221                                 in6_pcbfree(inp);
 222                         } else {
 223 #endif
 224                                 in_pcbdetach(inp);
 225                                 in_pcbfree(inp);
 226 #ifdef INET6
 227                         }
 228 #endif
 229                 } else {
 230 #ifdef INET6
 231                         if (isipv6)
 232                                 in6_pcbdetach(inp);
 233                         else
 234 #endif
 235                                 in_pcbdetach(inp);
 236                 }
 237         }
 238 }
 239
 240 /*
 241  * pru_detach() detaches the TCP protocol from the socket.
 242  * If the protocol state is non-embryonic, then can't
 243  * do this directly: have to initiate a pru_disconnect(),
 244  * which may finish later; embryonic TCB's can just
 245  * be discarded here.
 246  */
 247 static void
 248 tcp_usr_detach(struct socket *so)
 249 {
 250         struct inpcb *inp;
 251
 252         inp = sotoinpcb(so);
 253         KASSERT(inp != NULL, ("tcp_usr_detach: inp == NULL"));
 254         INP_INFO_WLOCK(&tcbinfo);
 255         INP_LOCK(inp);
 256         KASSERT(inp->inp_socket != NULL,
 257             ("tcp_usr_detach: inp_socket == NULL"));
 258         tcp_detach(so, inp);
 259         INP_INFO_WUNLOCK(&tcbinfo);
 260 }
 261
 262 /*
 263  * Give the socket an address.
 264  */
 265 static int
 266 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 267 {
 268         int error = 0;
 269         struct inpcb *inp;
 270         struct tcpcb *tp = NULL;
 271         struct sockaddr_in *sinp;
 272
 273         sinp = (struct sockaddr_in *)nam;
 274         if (nam->sa_len != sizeof (*sinp))
 275                 return (EINVAL);
 276         /*
 277          * Must check for multicast addresses and disallow binding
 278          * to them.
 279          */
 280         if (sinp->sin_family == AF_INET &&
 281             IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
 282                 return (EAFNOSUPPORT);
 283
 284         TCPDEBUG0;
 285         INP_INFO_WLOCK(&tcbinfo);
 286         inp = sotoinpcb(so);
 287         KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
 288         INP_LOCK(inp);
 289         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 290                 error = EINVAL;
 291                 goto out;
 292         }
 293         tp = intotcpcb(inp);
 294         TCPDEBUG1();
 295         error = in_pcbbind(inp, nam, td->td_ucred);
 296 out:
 297         TCPDEBUG2(PRU_BIND);
 298         INP_UNLOCK(inp);
 299         INP_INFO_WUNLOCK(&tcbinfo);
 300
 301         return (error);
 302 }
 303
 304 #ifdef INET6
 305 static int
 306 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
 307 {
 308         int error = 0;
 309         struct inpcb *inp;
 310         struct tcpcb *tp = NULL;
 311         struct sockaddr_in6 *sin6p;
 312
 313         sin6p = (struct sockaddr_in6 *)nam;
 314         if (nam->sa_len != sizeof (*sin6p))
 315                 return (EINVAL);
 316         /*
 317          * Must check for multicast addresses and disallow binding
 318          * to them.
 319          */
 320         if (sin6p->sin6_family == AF_INET6 &&
 321             IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
 322                 return (EAFNOSUPPORT);
 323
 324         TCPDEBUG0;
 325         INP_INFO_WLOCK(&tcbinfo);
 326         inp = sotoinpcb(so);
 327         KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
 328         INP_LOCK(inp);
 329         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 330                 error = EINVAL;
 331                 goto out;
 332         }
 333         tp = intotcpcb(inp);
 334         TCPDEBUG1();
 335         inp->inp_vflag &= ~INP_IPV4;
 336         inp->inp_vflag |= INP_IPV6;
 337         if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
 338                 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
 339                         inp->inp_vflag |= INP_IPV4;
 340                 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
 341                         struct sockaddr_in sin;
 342
 343                         in6_sin6_2_sin(&sin, sin6p);
 344                         inp->inp_vflag |= INP_IPV4;
 345                         inp->inp_vflag &= ~INP_IPV6;
 346                         error = in_pcbbind(inp, (struct sockaddr *)&sin,
 347                             td->td_ucred);
 348                         goto out;
 349                 }
 350         }
 351         error = in6_pcbbind(inp, nam, td->td_ucred);
 352 out:
 353         TCPDEBUG2(PRU_BIND);
 354         INP_UNLOCK(inp);
 355         INP_INFO_WUNLOCK(&tcbinfo);
 356         return (error);
 357 }
 358 #endif /* INET6 */
 359
 360 /*
 361  * Prepare to accept connections.
 362  */
 363 static int
 364 tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
 365 {
 366         int error = 0;
 367         struct inpcb *inp;
 368         struct tcpcb *tp = NULL;
 369
 370         TCPDEBUG0;
 371         INP_INFO_WLOCK(&tcbinfo);
 372         inp = sotoinpcb(so);
 373         KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
 374         INP_LOCK(inp);
 375         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 376                 error = EINVAL;
 377                 goto out;
 378         }
 379         tp = intotcpcb(inp);
 380         TCPDEBUG1();
 381         SOCK_LOCK(so);
 382         error = solisten_proto_check(so);
 383         if (error == 0 && inp->inp_lport == 0)
 384                 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
 385         if (error == 0) {
 386                 tp->t_state = TCPS_LISTEN;
 387                 solisten_proto(so, backlog);
 388         }
 389         SOCK_UNLOCK(so);
 390
 391 out:
 392         TCPDEBUG2(PRU_LISTEN);
 393         INP_UNLOCK(inp);
 394         INP_INFO_WUNLOCK(&tcbinfo);
 395         return (error);
 396 }
 397
 398 #ifdef INET6
 399 static int
 400 tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
 401 {
 402         int error = 0;
 403         struct inpcb *inp;
 404         struct tcpcb *tp = NULL;
 405
 406         TCPDEBUG0;
 407         INP_INFO_WLOCK(&tcbinfo);
 408         inp = sotoinpcb(so);
 409         KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
 410         INP_LOCK(inp);
 411         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 412                 error = EINVAL;
 413                 goto out;
 414         }
 415         tp = intotcpcb(inp);
 416         TCPDEBUG1();
 417         SOCK_LOCK(so);
 418         error = solisten_proto_check(so);
 419         if (error == 0 && inp->inp_lport == 0) {
 420                 inp->inp_vflag &= ~INP_IPV4;
 421                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
 422                         inp->inp_vflag |= INP_IPV4;
 423                 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
 424         }
 425         if (error == 0) {
 426                 tp->t_state = TCPS_LISTEN;
 427                 solisten_proto(so, backlog);
 428         }
 429         SOCK_UNLOCK(so);
 430
 431 out:
 432         TCPDEBUG2(PRU_LISTEN);
 433         INP_UNLOCK(inp);
 434         INP_INFO_WUNLOCK(&tcbinfo);
 435         return (error);
 436 }
 437 #endif /* INET6 */
 438
 439 /*
 440  * Initiate connection to peer.
 441  * Create a template for use in transmissions on this connection.
 442  * Enter SYN_SENT state, and mark socket as connecting.
 443  * Start keep-alive timer, and seed output sequence space.
 444  * Send initial segment on connection.
 445  */
 446 static int
 447 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 448 {
 449         int error = 0;
 450         struct inpcb *inp;
 451         struct tcpcb *tp = NULL;
 452         struct sockaddr_in *sinp;
 453
 454         sinp = (struct sockaddr_in *)nam;
 455         if (nam->sa_len != sizeof (*sinp))
 456                 return (EINVAL);
 457         /*
 458          * Must disallow TCP ``connections'' to multicast addresses.
 459          */
 460         if (sinp->sin_family == AF_INET
 461             && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
 462                 return (EAFNOSUPPORT);
 463         if (jailed(td->td_ucred))
 464                 prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr);
 465
 466         TCPDEBUG0;
 467         INP_INFO_WLOCK(&tcbinfo);
 468         inp = sotoinpcb(so);
 469         KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
 470         INP_LOCK(inp);
 471         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 472                 error = EINVAL;
 473                 goto out;
 474         }
 475         tp = intotcpcb(inp);
 476         TCPDEBUG1();
 477         if ((error = tcp_connect(tp, nam, td)) != 0)
 478                 goto out;
 479         error = tcp_output(tp);
 480 out:
 481         TCPDEBUG2(PRU_CONNECT);
 482         INP_UNLOCK(inp);
 483         INP_INFO_WUNLOCK(&tcbinfo);
 484         return (error);
 485 }
 486
 487 #ifdef INET6
 488 static int
 489 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
 490 {
 491         int error = 0;
 492         struct inpcb *inp;
 493         struct tcpcb *tp = NULL;
 494         struct sockaddr_in6 *sin6p;
 495
 496         TCPDEBUG0;
 497
 498         sin6p = (struct sockaddr_in6 *)nam;
 499         if (nam->sa_len != sizeof (*sin6p))
 500                 return (EINVAL);
 501         /*
 502          * Must disallow TCP ``connections'' to multicast addresses.
 503          */
 504         if (sin6p->sin6_family == AF_INET6
 505             && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
 506                 return (EAFNOSUPPORT);
 507
 508         INP_INFO_WLOCK(&tcbinfo);
 509         inp = sotoinpcb(so);
 510         KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
 511         INP_LOCK(inp);
 512         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 513                 error = EINVAL;
 514                 goto out;
 515         }
 516         tp = intotcpcb(inp);
 517         TCPDEBUG1();
 518         if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
 519                 struct sockaddr_in sin;
 520
 521                 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
 522                         error = EINVAL;
 523                         goto out;
 524                 }
 525
 526                 in6_sin6_2_sin(&sin, sin6p);
 527                 inp->inp_vflag |= INP_IPV4;
 528                 inp->inp_vflag &= ~INP_IPV6;
 529                 if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
 530                         goto out;
 531                 error = tcp_output(tp);
 532                 goto out;
 533         }
 534         inp->inp_vflag &= ~INP_IPV4;
 535         inp->inp_vflag |= INP_IPV6;
 536         inp->inp_inc.inc_isipv6 = 1;
 537         if ((error = tcp6_connect(tp, nam, td)) != 0)
 538                 goto out;
 539         error = tcp_output(tp);
 540
 541 out:
 542         TCPDEBUG2(PRU_CONNECT);
 543         INP_UNLOCK(inp);
 544         INP_INFO_WUNLOCK(&tcbinfo);
 545         return (error);
 546 }
 547 #endif /* INET6 */
 548
 549 /*
 550  * Initiate disconnect from peer.
 551  * If connection never passed embryonic stage, just drop;
 552  * else if don't need to let data drain, then can just drop anyways,
 553  * else have to begin TCP shutdown process: mark socket disconnecting,
 554  * drain unread data, state switch to reflect user close, and
 555  * send segment (e.g. FIN) to peer.  Socket will be really disconnected
 556  * when peer sends FIN and acks ours.
 557  *
 558  * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
 559  */
 560 static int
 561 tcp_usr_disconnect(struct socket *so)
 562 {
 563         struct inpcb *inp;
 564         struct tcpcb *tp = NULL;
 565         int error = 0;
 566
 567         TCPDEBUG0;
 568         INP_INFO_WLOCK(&tcbinfo);
 569         inp = sotoinpcb(so);
 570         KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
 571         INP_LOCK(inp);
 572         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 573                 error = ECONNRESET;
 574                 goto out;
 575         }
 576         tp = intotcpcb(inp);
 577         TCPDEBUG1();
 578         tcp_disconnect(tp);
 579 out:
 580         TCPDEBUG2(PRU_DISCONNECT);
 581         INP_UNLOCK(inp);
 582         INP_INFO_WUNLOCK(&tcbinfo);
 583         return (error);
 584 }
 585
 586 /*
 587  * Accept a connection.  Essentially all the work is
 588  * done at higher levels; just return the address
 589  * of the peer, storing through addr.
 590  */
 591 static int
 592 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
 593 {
 594         int error = 0;
 595         struct inpcb *inp = NULL;
 596         struct tcpcb *tp = NULL;
 597         struct in_addr addr;
 598         in_port_t port = 0;
 599         TCPDEBUG0;
 600
 601         if (so->so_state & SS_ISDISCONNECTED)
 602                 return (ECONNABORTED);
 603
 604         inp = sotoinpcb(so);
 605         KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
 606         INP_LOCK(inp);
 607         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 608                 error = ECONNABORTED;
 609                 goto out;
 610         }
 611         tp = intotcpcb(inp);
 612         TCPDEBUG1();
 613
 614         /*
 615          * We inline in_getpeeraddr and COMMON_END here, so that we can
 616          * copy the data of interest and defer the malloc until after we
 617          * release the lock.
 618          */
 619         port = inp->inp_fport;
 620         addr = inp->inp_faddr;
 621
 622 out:
 623         TCPDEBUG2(PRU_ACCEPT);
 624         INP_UNLOCK(inp);
 625         if (error == 0)
 626                 *nam = in_sockaddr(port, &addr);
 627         return error;
 628 }
 629
 630 #ifdef INET6
 631 static int
 632 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
 633 {
 634         struct inpcb *inp = NULL;
 635         int error = 0;
 636         struct tcpcb *tp = NULL;
 637         struct in_addr addr;
 638         struct in6_addr addr6;
 639         in_port_t port = 0;
 640         int v4 = 0;
 641         TCPDEBUG0;
 642
 643         if (so->so_state & SS_ISDISCONNECTED)
 644                 return (ECONNABORTED);
 645
 646         inp = sotoinpcb(so);
 647         KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
 648         INP_LOCK(inp);
 649         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 650                 error = ECONNABORTED;
 651                 goto out;
 652         }
 653         tp = intotcpcb(inp);
 654         TCPDEBUG1();
 655
 656         /*
 657          * We inline in6_mapped_peeraddr and COMMON_END here, so that we can
 658          * copy the data of interest and defer the malloc until after we
 659          * release the lock.
 660          */
 661         if (inp->inp_vflag & INP_IPV4) {
 662                 v4 = 1;
 663                 port = inp->inp_fport;
 664                 addr = inp->inp_faddr;
 665         } else {
 666                 port = inp->inp_fport;
 667                 addr6 = inp->in6p_faddr;
 668         }
 669
 670 out:
 671         TCPDEBUG2(PRU_ACCEPT);
 672         INP_UNLOCK(inp);
 673         if (error == 0) {
 674                 if (v4)
 675                         *nam = in6_v4mapsin6_sockaddr(port, &addr);
 676                 else
 677                         *nam = in6_sockaddr(port, &addr6);
 678         }
 679         return error;
 680 }
 681 #endif /* INET6 */
 682
 683 /*
 684  * Mark the connection as being incapable of further output.
 685  */
 686 static int
 687 tcp_usr_shutdown(struct socket *so)
 688 {
 689         int error = 0;
 690         struct inpcb *inp;
 691         struct tcpcb *tp = NULL;
 692
 693         TCPDEBUG0;
 694         INP_INFO_WLOCK(&tcbinfo);
 695         inp = sotoinpcb(so);
 696         KASSERT(inp != NULL, ("inp == NULL"));
 697         INP_LOCK(inp);
 698         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 699                 error = ECONNRESET;
 700                 goto out;
 701         }
 702         tp = intotcpcb(inp);
 703         TCPDEBUG1();
 704         socantsendmore(so);
 705         tcp_usrclosed(tp);
 706         error = tcp_output(tp);
 707
 708 out:
 709         TCPDEBUG2(PRU_SHUTDOWN);
 710         INP_UNLOCK(inp);
 711         INP_INFO_WUNLOCK(&tcbinfo);
 712
 713         return (error);
 714 }
 715
 716 /*
 717  * After a receive, possibly send window update to peer.
 718  */
 719 static int
 720 tcp_usr_rcvd(struct socket *so, int flags)
 721 {
 722         struct inpcb *inp;
 723         struct tcpcb *tp = NULL;
 724         int error = 0;
 725
 726         TCPDEBUG0;
 727         inp = sotoinpcb(so);
 728         KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
 729         INP_LOCK(inp);
 730         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 731                 error = ECONNRESET;
 732                 goto out;
 733         }
 734         tp = intotcpcb(inp);
 735         TCPDEBUG1();
 736         tcp_output(tp);
 737
 738 out:
 739         TCPDEBUG2(PRU_RCVD);
 740         INP_UNLOCK(inp);
 741         return (error);
 742 }
 743
 744 /*
 745  * Do a send by putting data in output queue and updating urgent
 746  * marker if URG set.  Possibly send more data.  Unlike the other
 747  * pru_*() routines, the mbuf chains are our responsibility.  We
 748  * must either enqueue them or free them.  The other pru_* routines
 749  * generally are caller-frees.
 750  */
 751 static int
 752 tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
 753     struct sockaddr *nam, struct mbuf *control, struct thread *td)
 754 {
 755         int error = 0;
 756         struct inpcb *inp;
 757         struct tcpcb *tp = NULL;
 758         int headlocked = 0;
 759 #ifdef INET6
 760         int isipv6;
 761 #endif
 762         TCPDEBUG0;
 763
 764         /*
 765          * We require the pcbinfo lock in two cases:
 766          *
 767          * (1) An implied connect is taking place, which can result in
 768          *     binding IPs and ports and hence modification of the pcb hash
 769          *     chains.
 770          *
 771          * (2) PRUS_EOF is set, resulting in explicit close on the send.
 772          */
 773         if ((nam != NULL) || (flags & PRUS_EOF)) {
 774                 INP_INFO_WLOCK(&tcbinfo);
 775                 headlocked = 1;
 776         }
 777         inp = sotoinpcb(so);
 778         KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
 779         INP_LOCK(inp);
 780         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 781                 if (control)
 782                         m_freem(control);
 783                 if (m)
 784                         m_freem(m);
 785                 error = ECONNRESET;
 786                 goto out;
 787         }
 788 #ifdef INET6
 789         isipv6 = nam && nam->sa_family == AF_INET6;
 790 #endif /* INET6 */
 791         tp = intotcpcb(inp);
 792         TCPDEBUG1();
 793         if (control) {
 794                 /* TCP doesn't do control messages (rights, creds, etc) */
 795                 if (control->m_len) {
 796                         m_freem(control);
 797                         if (m)
 798                                 m_freem(m);
 799                         error = EINVAL;
 800                         goto out;
 801                 }
 802                 m_freem(control);       /* empty control, just free it */
 803         }
 804         if (!(flags & PRUS_OOB)) {
 805                 sbappendstream(&so->so_snd, m);
 806                 if (nam && tp->t_state < TCPS_SYN_SENT) {
 807                         /*
 808                          * Do implied connect if not yet connected,
 809                          * initialize window to default value, and
 810                          * initialize maxseg/maxopd using peer's cached
 811                          * MSS.
 812                          */
 813                         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 814 #ifdef INET6
 815                         if (isipv6)
 816                                 error = tcp6_connect(tp, nam, td);
 817                         else
 818 #endif /* INET6 */
 819                         error = tcp_connect(tp, nam, td);
 820                         if (error)
 821                                 goto out;
 822                         tp->snd_wnd = TTCP_CLIENT_SND_WND;
 823                         tcp_mss(tp, -1);
 824                 }
 825                 if (flags & PRUS_EOF) {
 826                         /*
 827                          * Close the send side of the connection after
 828                          * the data is sent.
 829                          */
 830                         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 831                         socantsendmore(so);
 832                         tcp_usrclosed(tp);
 833                 }
 834                 if (headlocked) {
 835                         INP_INFO_WUNLOCK(&tcbinfo);
 836                         headlocked = 0;
 837                 }
 838                 if (tp != NULL) {
 839                         if (flags & PRUS_MORETOCOME)
 840                                 tp->t_flags |= TF_MORETOCOME;
 841                         error = tcp_output(tp);
 842                         if (flags & PRUS_MORETOCOME)
 843                                 tp->t_flags &= ~TF_MORETOCOME;
 844                 }
 845         } else {
 846                 /*
 847                  * XXXRW: PRUS_EOF not implemented with PRUS_OOB?
 848                  */
 849                 SOCKBUF_LOCK(&so->so_snd);
 850                 if (sbspace(&so->so_snd) < -512) {
 851                         SOCKBUF_UNLOCK(&so->so_snd);
 852                         m_freem(m);
 853                         error = ENOBUFS;
 854                         goto out;
 855                 }
 856                 /*
 857                  * According to RFC961 (Assigned Protocols),
 858                  * the urgent pointer points to the last octet
 859                  * of urgent data.  We continue, however,
 860                  * to consider it to indicate the first octet
 861                  * of data past the urgent section.
 862                  * Otherwise, snd_up should be one lower.
 863                  */
 864                 sbappendstream_locked(&so->so_snd, m);
 865                 SOCKBUF_UNLOCK(&so->so_snd);
 866                 if (nam && tp->t_state < TCPS_SYN_SENT) {
 867                         /*
 868                          * Do implied connect if not yet connected,
 869                          * initialize window to default value, and
 870                          * initialize maxseg/maxopd using peer's cached
 871                          * MSS.
 872                          */
 873                         INP_INFO_WLOCK_ASSERT(&tcbinfo);
 874 #ifdef INET6
 875                         if (isipv6)
 876                                 error = tcp6_connect(tp, nam, td);
 877                         else
 878 #endif /* INET6 */
 879                         error = tcp_connect(tp, nam, td);
 880                         if (error)
 881                                 goto out;
 882                         tp->snd_wnd = TTCP_CLIENT_SND_WND;
 883                         tcp_mss(tp, -1);
 884                         INP_INFO_WUNLOCK(&tcbinfo);
 885                         headlocked = 0;
 886                 } else if (nam) {
 887                         INP_INFO_WUNLOCK(&tcbinfo);
 888                         headlocked = 0;
 889                 }
 890                 tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
 891                 tp->t_flags |= TF_FORCEDATA;
 892                 error = tcp_output(tp);
 893                 tp->t_flags &= ~TF_FORCEDATA;
 894         }
 895 out:
 896         TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
 897                   ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
 898         INP_UNLOCK(inp);
 899         if (headlocked)
 900                 INP_INFO_WUNLOCK(&tcbinfo);
 901         return (error);
 902 }
 903
 904 /*
 905  * Abort the TCP.  Drop the connection abruptly.
 906  */
 907 static void
 908 tcp_usr_abort(struct socket *so)
 909 {
 910         struct inpcb *inp;
 911         struct tcpcb *tp = NULL;
 912         TCPDEBUG0;
 913
 914         inp = sotoinpcb(so);
 915         KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
 916
 917         INP_INFO_WLOCK(&tcbinfo);
 918         INP_LOCK(inp);
 919         KASSERT(inp->inp_socket != NULL,
 920             ("tcp_usr_abort: inp_socket == NULL"));
 921
 922         /*
 923          * If we still have full TCP state, and we're not dropped, drop.
 924          */
 925         if (!(inp->inp_vflag & INP_TIMEWAIT) &&
 926             !(inp->inp_vflag & INP_DROPPED)) {
 927                 tp = intotcpcb(inp);
 928                 TCPDEBUG1();
 929                 tcp_drop(tp, ECONNABORTED);
 930                 TCPDEBUG2(PRU_ABORT);
 931         }
 932         if (!(inp->inp_vflag & INP_DROPPED)) {
 933                 SOCK_LOCK(so);
 934                 so->so_state |= SS_PROTOREF;
 935                 SOCK_UNLOCK(so);
 936                 inp->inp_vflag |= INP_SOCKREF;
 937         }
 938         INP_UNLOCK(inp);
 939         INP_INFO_WUNLOCK(&tcbinfo);
 940 }
 941
 942 /*
 943  * TCP socket is closed.  Start friendly disconnect.
 944  */
 945 static void
 946 tcp_usr_close(struct socket *so)
 947 {
 948         struct inpcb *inp;
 949         struct tcpcb *tp = NULL;
 950         TCPDEBUG0;
 951
 952         inp = sotoinpcb(so);
 953         KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
 954
 955         INP_INFO_WLOCK(&tcbinfo);
 956         INP_LOCK(inp);
 957         KASSERT(inp->inp_socket != NULL,
 958             ("tcp_usr_close: inp_socket == NULL"));
 959
 960         /*
 961          * If we still have full TCP state, and we're not dropped, initiate
 962          * a disconnect.
 963          */
 964         if (!(inp->inp_vflag & INP_TIMEWAIT) &&
 965             !(inp->inp_vflag & INP_DROPPED)) {
 966                 tp = intotcpcb(inp);
 967                 TCPDEBUG1();
 968                 tcp_disconnect(tp);
 969                 TCPDEBUG2(PRU_CLOSE);
 970         }
 971         if (!(inp->inp_vflag & INP_DROPPED)) {
 972                 SOCK_LOCK(so);
 973                 so->so_state |= SS_PROTOREF;
 974                 SOCK_UNLOCK(so);
 975                 inp->inp_vflag |= INP_SOCKREF;
 976         }
 977         INP_UNLOCK(inp);
 978         INP_INFO_WUNLOCK(&tcbinfo);
 979 }
 980
 981 /*
 982  * Receive out-of-band data.
 983  */
 984 static int
 985 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
 986 {
 987         int error = 0;
 988         struct inpcb *inp;
 989         struct tcpcb *tp = NULL;
 990
 991         TCPDEBUG0;
 992         inp = sotoinpcb(so);
 993         KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
 994         INP_LOCK(inp);
 995         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
 996                 error = ECONNRESET;
 997                 goto out;
 998         }
 999         tp = intotcpcb(inp);
1000         TCPDEBUG1();
1001         if ((so->so_oobmark == 0 &&
1002              (so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
1003             so->so_options & SO_OOBINLINE ||
1004             tp->t_oobflags & TCPOOB_HADDATA) {
1005                 error = EINVAL;
1006                 goto out;
1007         }
1008         if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
1009                 error = EWOULDBLOCK;
1010                 goto out;
1011         }
1012         m->m_len = 1;
1013         *mtod(m, caddr_t) = tp->t_iobc;
1014         if ((flags & MSG_PEEK) == 0)
1015                 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
1016
1017 out:
1018         TCPDEBUG2(PRU_RCVOOB);
1019         INP_UNLOCK(inp);
1020         return (error);
1021 }
1022
1023 struct pr_usrreqs tcp_usrreqs = {
1024         .pru_abort =            tcp_usr_abort,
1025         .pru_accept =           tcp_usr_accept,
1026         .pru_attach =           tcp_usr_attach,
1027         .pru_bind =             tcp_usr_bind,
1028         .pru_connect =          tcp_usr_connect,
1029         .pru_control =          in_control,
1030         .pru_detach =           tcp_usr_detach,
1031         .pru_disconnect =       tcp_usr_disconnect,
1032         .pru_listen =           tcp_usr_listen,
1033         .pru_peeraddr =         in_getpeeraddr,
1034         .pru_rcvd =             tcp_usr_rcvd,
1035         .pru_rcvoob =           tcp_usr_rcvoob,
1036         .pru_send =             tcp_usr_send,
1037         .pru_shutdown =         tcp_usr_shutdown,
1038         .pru_sockaddr =         in_getsockaddr,
1039         .pru_sosetlabel =       in_pcbsosetlabel,
1040         .pru_close =            tcp_usr_close,
1041 };
1042
1043 #ifdef INET6
1044 struct pr_usrreqs tcp6_usrreqs = {
1045         .pru_abort =            tcp_usr_abort,
1046         .pru_accept =           tcp6_usr_accept,
1047         .pru_attach =           tcp_usr_attach,
1048         .pru_bind =             tcp6_usr_bind,
1049         .pru_connect =          tcp6_usr_connect,
1050         .pru_control =          in6_control,
1051         .pru_detach =           tcp_usr_detach,
1052         .pru_disconnect =       tcp_usr_disconnect,
1053         .pru_listen =           tcp6_usr_listen,
1054         .pru_peeraddr =         in6_mapped_peeraddr,
1055         .pru_rcvd =             tcp_usr_rcvd,
1056         .pru_rcvoob =           tcp_usr_rcvoob,
1057         .pru_send =             tcp_usr_send,
1058         .pru_shutdown =         tcp_usr_shutdown,
1059         .pru_sockaddr =         in6_mapped_sockaddr,
1060         .pru_sosetlabel =       in_pcbsosetlabel,
1061         .pru_close =            tcp_usr_close,
1062 };
1063 #endif /* INET6 */
1064
1065 /*
1066  * Common subroutine to open a TCP connection to remote host specified
1067  * by struct sockaddr_in in mbuf *nam.  Call in_pcbbind to assign a local
1068  * port number if needed.  Call in_pcbconnect_setup to do the routing and
1069  * to choose a local host address (interface).  If there is an existing
1070  * incarnation of the same connection in TIME-WAIT state and if the remote
1071  * host was sending CC options and if the connection duration was < MSL, then
1072  * truncate the previous TIME-WAIT state and proceed.
1073  * Initialize connection parameters and enter SYN-SENT state.
1074  */
1075 static int
1076 tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1077 {
1078         struct inpcb *inp = tp->t_inpcb, *oinp;
1079         struct socket *so = inp->inp_socket;
1080         struct in_addr laddr;
1081         u_short lport;
1082         int error;
1083
1084         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1085         INP_LOCK_ASSERT(inp);
1086
1087         if (inp->inp_lport == 0) {
1088                 error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1089                 if (error)
1090                         return error;
1091         }
1092
1093         /*
1094          * Cannot simply call in_pcbconnect, because there might be an
1095          * earlier incarnation of this same connection still in
1096          * TIME_WAIT state, creating an ADDRINUSE error.
1097          */
1098         laddr = inp->inp_laddr;
1099         lport = inp->inp_lport;
1100         error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
1101             &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
1102         if (error && oinp == NULL)
1103                 return error;
1104         if (oinp)
1105                 return EADDRINUSE;
1106         inp->inp_laddr = laddr;
1107         in_pcbrehash(inp);
1108
1109         /*
1110          * Compute window scaling to request:
1111          * Scale to fit into sweet spot.  See tcp_syncache.c.
1112          * XXX: This should move to tcp_output().
1113          */
1114         while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1115             (TCP_MAXWIN << tp->request_r_scale) < sb_max)
1116                 tp->request_r_scale++;
1117
1118         soisconnecting(so);
1119         tcpstat.tcps_connattempt++;
1120         tp->t_state = TCPS_SYN_SENT;
1121         tcp_timer_activate(tp, TT_KEEP, tcp_keepinit);
1122         tp->iss = tcp_new_isn(tp);
1123         tp->t_bw_rtseq = tp->iss;
1124         tcp_sendseqinit(tp);
1125
1126         return 0;
1127 }
1128
1129 #ifdef INET6
1130 static int
1131 tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
1132 {
1133         struct inpcb *inp = tp->t_inpcb, *oinp;
1134         struct socket *so = inp->inp_socket;
1135         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
1136         struct in6_addr *addr6;
1137         int error;
1138
1139         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1140         INP_LOCK_ASSERT(inp);
1141
1142         if (inp->inp_lport == 0) {
1143                 error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
1144                 if (error)
1145                         return error;
1146         }
1147
1148         /*
1149          * Cannot simply call in_pcbconnect, because there might be an
1150          * earlier incarnation of this same connection still in
1151          * TIME_WAIT state, creating an ADDRINUSE error.
1152          * in6_pcbladdr() also handles scope zone IDs.
1153          */
1154         error = in6_pcbladdr(inp, nam, &addr6);
1155         if (error)
1156                 return error;
1157         oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
1158                                   &sin6->sin6_addr, sin6->sin6_port,
1159                                   IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
1160                                   ? addr6
1161                                   : &inp->in6p_laddr,
1162                                   inp->inp_lport,  0, NULL);
1163         if (oinp)
1164                 return EADDRINUSE;
1165         if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
1166                 inp->in6p_laddr = *addr6;
1167         inp->in6p_faddr = sin6->sin6_addr;
1168         inp->inp_fport = sin6->sin6_port;
1169         /* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
1170         inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
1171         if (inp->in6p_flags & IN6P_AUTOFLOWLABEL)
1172                 inp->in6p_flowinfo |=
1173                     (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
1174         in_pcbrehash(inp);
1175
1176         /* Compute window scaling to request.  */
1177         while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
1178             (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
1179                 tp->request_r_scale++;
1180
1181         soisconnecting(so);
1182         tcpstat.tcps_connattempt++;
1183         tp->t_state = TCPS_SYN_SENT;
1184         tcp_timer_activate(tp, TT_KEEP, tcp_keepinit);
1185         tp->iss = tcp_new_isn(tp);
1186         tp->t_bw_rtseq = tp->iss;
1187         tcp_sendseqinit(tp);
1188
1189         return 0;
1190 }
1191 #endif /* INET6 */
1192
1193 /*
1194  * Export TCP internal state information via a struct tcp_info, based on the
1195  * Linux 2.6 API.  Not ABI compatible as our constants are mapped differently
1196  * (TCP state machine, etc).  We export all information using FreeBSD-native
1197  * constants -- for example, the numeric values for tcpi_state will differ
1198  * from Linux.
1199  */
1200 static void
1201 tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
1202 {
1203
1204         INP_LOCK_ASSERT(tp->t_inpcb);
1205         bzero(ti, sizeof(*ti));
1206
1207         ti->tcpi_state = tp->t_state;
1208         if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
1209                 ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
1210         if (tp->t_flags & TF_SACK_PERMIT)
1211                 ti->tcpi_options |= TCPI_OPT_SACK;
1212         if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
1213                 ti->tcpi_options |= TCPI_OPT_WSCALE;
1214                 ti->tcpi_snd_wscale = tp->snd_scale;
1215                 ti->tcpi_rcv_wscale = tp->rcv_scale;
1216         }
1217
1218         ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
1219         ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
1220
1221         ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
1222         ti->tcpi_snd_cwnd = tp->snd_cwnd;
1223
1224         /*
1225          * FreeBSD-specific extension fields for tcp_info.
1226          */
1227         ti->tcpi_rcv_space = tp->rcv_wnd;
1228         ti->tcpi_snd_wnd = tp->snd_wnd;
1229         ti->tcpi_snd_bwnd = tp->snd_bwnd;
1230 }
1231
1232 /*
1233  * The new sockopt interface makes it possible for us to block in the
1234  * copyin/out step (if we take a page fault).  Taking a page fault at
1235  * splnet() is probably a Bad Thing.  (Since sockets and pcbs both now
1236  * use TSM, there probably isn't any need for this function to run at
1237  * splnet() any more.  This needs more examination.)
1238  *
1239  * XXXRW: The locking here is wrong; we may take a page fault while holding
1240  * the inpcb lock.
1241  */
1242 int
1243 tcp_ctloutput(struct socket *so, struct sockopt *sopt)
1244 {
1245         int     error, opt, optval;
1246         struct  inpcb *inp;
1247         struct  tcpcb *tp;
1248         struct  tcp_info ti;
1249
1250         error = 0;
1251         inp = sotoinpcb(so);
1252         KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
1253         INP_LOCK(inp);
1254         if (sopt->sopt_level != IPPROTO_TCP) {
1255                 INP_UNLOCK(inp);
1256 #ifdef INET6
1257                 if (INP_CHECK_SOCKAF(so, AF_INET6))
1258                         error = ip6_ctloutput(so, sopt);
1259                 else
1260 #endif /* INET6 */
1261                 error = ip_ctloutput(so, sopt);
1262                 return (error);
1263         }
1264         if (inp->inp_vflag & (INP_TIMEWAIT | INP_DROPPED)) {
1265                 error = ECONNRESET;
1266                 goto out;
1267         }
1268         tp = intotcpcb(inp);
1269
1270         switch (sopt->sopt_dir) {
1271         case SOPT_SET:
1272                 switch (sopt->sopt_name) {
1273 #ifdef TCP_SIGNATURE
1274                 case TCP_MD5SIG:
1275                         error = sooptcopyin(sopt, &optval, sizeof optval,
1276                                             sizeof optval);
1277                         if (error)
1278                                 break;
1279
1280                         if (optval > 0)
1281                                 tp->t_flags |= TF_SIGNATURE;
1282                         else
1283                                 tp->t_flags &= ~TF_SIGNATURE;
1284                         break;
1285 #endif /* TCP_SIGNATURE */
1286                 case TCP_NODELAY:
1287                 case TCP_NOOPT:
1288                         error = sooptcopyin(sopt, &optval, sizeof optval,
1289                                             sizeof optval);
1290                         if (error)
1291                                 break;
1292
1293                         switch (sopt->sopt_name) {
1294                         case TCP_NODELAY:
1295                                 opt = TF_NODELAY;
1296                                 break;
1297                         case TCP_NOOPT:
1298                                 opt = TF_NOOPT;
1299                                 break;
1300                         default:
1301                                 opt = 0; /* dead code to fool gcc */
1302                                 break;
1303                         }
1304
1305                         if (optval)
1306                                 tp->t_flags |= opt;
1307                         else
1308                                 tp->t_flags &= ~opt;
1309                         break;
1310
1311                 case TCP_NOPUSH:
1312                         error = sooptcopyin(sopt, &optval, sizeof optval,
1313                                             sizeof optval);
1314                         if (error)
1315                                 break;
1316
1317                         if (optval)
1318                                 tp->t_flags |= TF_NOPUSH;
1319                         else {
1320                                 tp->t_flags &= ~TF_NOPUSH;
1321                                 error = tcp_output(tp);
1322                         }
1323                         break;
1324
1325                 case TCP_MAXSEG:
1326                         error = sooptcopyin(sopt, &optval, sizeof optval,
1327                                             sizeof optval);
1328                         if (error)
1329                                 break;
1330
1331                         if (optval > 0 && optval <= tp->t_maxseg &&
1332                             optval + 40 >= tcp_minmss)
1333                                 tp->t_maxseg = optval;
1334                         else
1335                                 error = EINVAL;
1336                         break;
1337
1338                 case TCP_INFO:
1339                         error = EINVAL;
1340                         break;
1341
1342                 default:
1343                         error = ENOPROTOOPT;
1344                         break;
1345                 }
1346                 break;
1347
1348         case SOPT_GET:
1349                 switch (sopt->sopt_name) {
1350 #ifdef TCP_SIGNATURE
1351                 case TCP_MD5SIG:
1352                         optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0;
1353                         error = sooptcopyout(sopt, &optval, sizeof optval);
1354                         break;
1355 #endif
1356                 case TCP_NODELAY:
1357                         optval = tp->t_flags & TF_NODELAY;
1358                         error = sooptcopyout(sopt, &optval, sizeof optval);
1359                         break;
1360                 case TCP_MAXSEG:
1361                         optval = tp->t_maxseg;
1362                         error = sooptcopyout(sopt, &optval, sizeof optval);
1363                         break;
1364                 case TCP_NOOPT:
1365                         optval = tp->t_flags & TF_NOOPT;
1366                         error = sooptcopyout(sopt, &optval, sizeof optval);
1367                         break;
1368                 case TCP_NOPUSH:
1369                         optval = tp->t_flags & TF_NOPUSH;
1370                         error = sooptcopyout(sopt, &optval, sizeof optval);
1371                         break;
1372                 case TCP_INFO:
1373                         tcp_fill_info(tp, &ti);
1374                         error = sooptcopyout(sopt, &ti, sizeof ti);
1375                         break;
1376                 default:
1377                         error = ENOPROTOOPT;
1378                         break;
1379                 }
1380                 break;
1381         }
1382 out:
1383         INP_UNLOCK(inp);
1384         return (error);
1385 }
1386
1387 /*
1388  * tcp_sendspace and tcp_recvspace are the default send and receive window
1389  * sizes, respectively.  These are obsolescent (this information should
1390  * be set by the route).
1391  */
1392 u_long  tcp_sendspace = 1024*32;
1393 SYSCTL_ULONG(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW,
1394     &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
1395 u_long  tcp_recvspace = 1024*64;
1396 SYSCTL_ULONG(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
1397     &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
1398
1399 /*
1400  * Attach TCP protocol to socket, allocating
1401  * internet protocol control block, tcp control block,
1402  * bufer space, and entering LISTEN state if to accept connections.
1403  */
1404 static int
1405 tcp_attach(struct socket *so)
1406 {
1407         struct tcpcb *tp;
1408         struct inpcb *inp;
1409         int error;
1410 #ifdef INET6
1411         int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0;
1412 #endif
1413
1414         if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1415                 error = soreserve(so, tcp_sendspace, tcp_recvspace);
1416                 if (error)
1417                         return (error);
1418         }
1419         so->so_rcv.sb_flags |= SB_AUTOSIZE;
1420         so->so_snd.sb_flags |= SB_AUTOSIZE;
1421         INP_INFO_WLOCK(&tcbinfo);
1422         error = in_pcballoc(so, &tcbinfo);
1423         if (error) {
1424                 INP_INFO_WUNLOCK(&tcbinfo);
1425                 return (error);
1426         }
1427         inp = sotoinpcb(so);
1428 #ifdef INET6
1429         if (isipv6) {
1430                 inp->inp_vflag |= INP_IPV6;
1431                 inp->in6p_hops = -1;    /* use kernel default */
1432         }
1433         else
1434 #endif
1435         inp->inp_vflag |= INP_IPV4;
1436         tp = tcp_newtcpcb(inp);
1437         if (tp == NULL) {
1438 #ifdef INET6
1439                 if (isipv6) {
1440                         in6_pcbdetach(inp);
1441                         in6_pcbfree(inp);
1442                 } else {
1443 #endif
1444                         in_pcbdetach(inp);
1445                         in_pcbfree(inp);
1446 #ifdef INET6
1447                 }
1448 #endif
1449                 INP_INFO_WUNLOCK(&tcbinfo);
1450                 return (ENOBUFS);
1451         }
1452         tp->t_state = TCPS_CLOSED;
1453         INP_UNLOCK(inp);
1454         INP_INFO_WUNLOCK(&tcbinfo);
1455         return (0);
1456 }
1457
1458 /*
1459  * Initiate (or continue) disconnect.
1460  * If embryonic state, just send reset (once).
1461  * If in ``let data drain'' option and linger null, just drop.
1462  * Otherwise (hard), mark socket disconnecting and drop
1463  * current input data; switch states based on user close, and
1464  * send segment to peer (with FIN).
1465  */
1466 static void
1467 tcp_disconnect(struct tcpcb *tp)
1468 {
1469         struct inpcb *inp = tp->t_inpcb;
1470         struct socket *so = inp->inp_socket;
1471
1472         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1473         INP_LOCK_ASSERT(inp);
1474
1475         /*
1476          * Neither tcp_close() nor tcp_drop() should return NULL, as the
1477          * socket is still open.
1478          */
1479         if (tp->t_state < TCPS_ESTABLISHED) {
1480                 tp = tcp_close(tp);
1481                 KASSERT(tp != NULL,
1482                     ("tcp_disconnect: tcp_close() returned NULL"));
1483         } else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
1484                 tp = tcp_drop(tp, 0);
1485                 KASSERT(tp != NULL,
1486                     ("tcp_disconnect: tcp_drop() returned NULL"));
1487         } else {
1488                 soisdisconnecting(so);
1489                 sbflush(&so->so_rcv);
1490                 tcp_usrclosed(tp);
1491                 if (!(inp->inp_vflag & INP_DROPPED))
1492                         tcp_output(tp);
1493         }
1494 }
1495
1496 /*
1497  * User issued close, and wish to trail through shutdown states:
1498  * if never received SYN, just forget it.  If got a SYN from peer,
1499  * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
1500  * If already got a FIN from peer, then almost done; go to LAST_ACK
1501  * state.  In all other cases, have already sent FIN to peer (e.g.
1502  * after PRU_SHUTDOWN), and just have to play tedious game waiting
1503  * for peer to send FIN or not respond to keep-alives, etc.
1504  * We can let the user exit from the close as soon as the FIN is acked.
1505  */
1506 static void
1507 tcp_usrclosed(struct tcpcb *tp)
1508 {
1509
1510         INP_INFO_WLOCK_ASSERT(&tcbinfo);
1511         INP_LOCK_ASSERT(tp->t_inpcb);
1512
1513         switch (tp->t_state) {
1514         case TCPS_CLOSED:
1515         case TCPS_LISTEN:
1516                 tp->t_state = TCPS_CLOSED;
1517                 tp = tcp_close(tp);
1518                 /*
1519                  * tcp_close() should never return NULL here as the socket is
1520                  * still open.
1521                  */
1522                 KASSERT(tp != NULL,
1523                     ("tcp_usrclosed: tcp_close() returned NULL"));
1524                 break;
1525
1526         case TCPS_SYN_SENT:
1527         case TCPS_SYN_RECEIVED:
1528                 tp->t_flags |= TF_NEEDFIN;
1529                 break;
1530
1531         case TCPS_ESTABLISHED:
1532                 tp->t_state = TCPS_FIN_WAIT_1;
1533                 break;
1534
1535         case TCPS_CLOSE_WAIT:
1536                 tp->t_state = TCPS_LAST_ACK;
1537                 break;
1538         }
1539         if (tp->t_state >= TCPS_FIN_WAIT_2) {
1540                 soisdisconnected(tp->t_inpcb->inp_socket);
1541                 /* Prevent the connection hanging in FIN_WAIT_2 forever. */
1542                 if (tp->t_state == TCPS_FIN_WAIT_2) {
1543                         int timeout;
1544
1545                         timeout = (tcp_fast_finwait2_recycle) ?
1546                             tcp_finwait2_timeout : tcp_maxidle;
1547                         tcp_timer_activate(tp, TT_2MSL, timeout);
1548                 }
1549         }
1550 }
1551
1552 #ifdef DDB
1553 static void
1554 db_print_indent(int indent)
1555 {
1556         int i;
1557
1558         for (i = 0; i < indent; i++)
1559                 db_printf(" ");
1560 }
1561
1562 static void
1563 db_print_tstate(int t_state)
1564 {
1565
1566         switch (t_state) {
1567         case TCPS_CLOSED:
1568                 db_printf("TCPS_CLOSED");
1569                 return;
1570
1571         case TCPS_LISTEN:
1572                 db_printf("TCPS_LISTEN");
1573                 return;
1574
1575         case TCPS_SYN_SENT:
1576                 db_printf("TCPS_SYN_SENT");
1577                 return;
1578
1579         case TCPS_SYN_RECEIVED:
1580                 db_printf("TCPS_SYN_RECEIVED");
1581                 return;
1582
1583         case TCPS_ESTABLISHED:
1584                 db_printf("TCPS_ESTABLISHED");
1585                 return;
1586
1587         case TCPS_CLOSE_WAIT:
1588                 db_printf("TCPS_CLOSE_WAIT");
1589                 return;
1590
1591         case TCPS_FIN_WAIT_1:
1592                 db_printf("TCPS_FIN_WAIT_1");
1593                 return;
1594
1595         case TCPS_CLOSING:
1596                 db_printf("TCPS_CLOSING");
1597                 return;
1598
1599         case TCPS_LAST_ACK:
1600                 db_printf("TCPS_LAST_ACK");
1601                 return;
1602
1603         case TCPS_FIN_WAIT_2:
1604                 db_printf("TCPS_FIN_WAIT_2");
1605                 return;
1606
1607         case TCPS_TIME_WAIT:
1608                 db_printf("TCPS_TIME_WAIT");
1609                 return;
1610
1611         default:
1612                 db_printf("unknown");
1613                 return;
1614         }
1615 }
1616
1617 static void
1618 db_print_tflags(u_int t_flags)
1619 {
1620         int comma;
1621
1622         comma = 0;
1623         if (t_flags & TF_ACKNOW) {
1624                 db_printf("%sTF_ACKNOW", comma ? ", " : "");
1625                 comma = 1;
1626         }
1627         if (t_flags & TF_DELACK) {
1628                 db_printf("%sTF_DELACK", comma ? ", " : "");
1629                 comma = 1;
1630         }
1631         if (t_flags & TF_NODELAY) {
1632                 db_printf("%sTF_NODELAY", comma ? ", " : "");
1633                 comma = 1;
1634         }
1635         if (t_flags & TF_NOOPT) {
1636                 db_printf("%sTF_NOOPT", comma ? ", " : "");
1637                 comma = 1;
1638         }
1639         if (t_flags & TF_SENTFIN) {
1640                 db_printf("%sTF_SENTFIN", comma ? ", " : "");
1641                 comma = 1;
1642         }
1643         if (t_flags & TF_REQ_SCALE) {
1644                 db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
1645                 comma = 1;
1646         }
1647         if (t_flags & TF_RCVD_SCALE) {
1648                 db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
1649                 comma = 1;
1650         }
1651         if (t_flags & TF_REQ_TSTMP) {
1652                 db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
1653                 comma = 1;
1654         }
1655         if (t_flags & TF_RCVD_TSTMP) {
1656                 db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
1657                 comma = 1;
1658         }
1659         if (t_flags & TF_SACK_PERMIT) {
1660                 db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
1661                 comma = 1;
1662         }
1663         if (t_flags & TF_NEEDSYN) {
1664                 db_printf("%sTF_NEEDSYN", comma ? ", " : "");
1665                 comma = 1;
1666         }
1667         if (t_flags & TF_NEEDFIN) {
1668                 db_printf("%sTF_NEEDFIN", comma ? ", " : "");
1669                 comma = 1;
1670         }
1671         if (t_flags & TF_NOPUSH) {
1672                 db_printf("%sTF_NOPUSH", comma ? ", " : "");
1673                 comma = 1;
1674         }
1675         if (t_flags & TF_NOPUSH) {
1676                 db_printf("%sTF_NOPUSH", comma ? ", " : "");
1677                 comma = 1;
1678         }
1679         if (t_flags & TF_MORETOCOME) {
1680                 db_printf("%sTF_MORETOCOME", comma ? ", " : "");
1681                 comma = 1;
1682         }
1683         if (t_flags & TF_LQ_OVERFLOW) {
1684                 db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
1685                 comma = 1;
1686         }
1687         if (t_flags & TF_LASTIDLE) {
1688                 db_printf("%sTF_LASTIDLE", comma ? ", " : "");
1689                 comma = 1;
1690         }
1691         if (t_flags & TF_RXWIN0SENT) {
1692                 db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
1693                 comma = 1;
1694         }
1695         if (t_flags & TF_FASTRECOVERY) {
1696                 db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
1697                 comma = 1;
1698         }
1699         if (t_flags & TF_WASFRECOVERY) {
1700                 db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
1701                 comma = 1;
1702         }
1703         if (t_flags & TF_SIGNATURE) {
1704                 db_printf("%sTF_SIGNATURE", comma ? ", " : "");
1705                 comma = 1;
1706         }
1707         if (t_flags & TF_FORCEDATA) {
1708                 db_printf("%sTF_FORCEDATA", comma ? ", " : "");
1709                 comma = 1;
1710         }
1711         if (t_flags & TF_TSO) {
1712                 db_printf("%sTF_TSO", comma ? ", " : "");
1713                 comma = 1;
1714         }
1715 }
1716
1717 static void
1718 db_print_toobflags(char t_oobflags)
1719 {
1720         int comma;
1721
1722         comma = 0;
1723         if (t_oobflags & TCPOOB_HAVEDATA) {
1724                 db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
1725                 comma = 1;
1726         }
1727         if (t_oobflags & TCPOOB_HADDATA) {
1728                 db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
1729                 comma = 1;
1730         }
1731 }
1732
1733 static void
1734 db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
1735 {
1736
1737         db_print_indent(indent);
1738         db_printf("%s at %p\n", name, tp);
1739
1740         indent += 2;
1741
1742         db_print_indent(indent);
1743         db_printf("t_segq first: %p   t_segqlen: %d   t_dupacks: %d\n",
1744            LIST_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
1745
1746         db_print_indent(indent);
1747         db_printf("tt_rexmt: %p   tt_persist: %p   tt_keep: %p\n",
1748             &tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
1749
1750         db_print_indent(indent);
1751         db_printf("tt_2msl: %p   tt_delack: %p   t_inpcb: %p\n", &tp->t_timers->tt_2msl,
1752             &tp->t_timers->tt_delack, tp->t_inpcb);
1753
1754         db_print_indent(indent);
1755         db_printf("t_state: %d (", tp->t_state);
1756         db_print_tstate(tp->t_state);
1757         db_printf(")\n");
1758
1759         db_print_indent(indent);
1760         db_printf("t_flags: 0x%x (", tp->t_flags);
1761         db_print_tflags(tp->t_flags);
1762         db_printf(")\n");
1763
1764         db_print_indent(indent);
1765         db_printf("snd_una: 0x%08x   snd_max: 0x%08x   snd_nxt: x0%08x\n",
1766             tp->snd_una, tp->snd_max, tp->snd_nxt);
1767
1768         db_print_indent(indent);
1769         db_printf("snd_up: 0x%08x   snd_wl1: 0x%08x   snd_wl2: 0x%08x\n",
1770            tp->snd_up, tp->snd_wl1, tp->snd_wl2);
1771
1772         db_print_indent(indent);
1773         db_printf("iss: 0x%08x   irs: 0x%08x   rcv_nxt: 0x%08x\n",
1774             tp->iss, tp->irs, tp->rcv_nxt);
1775
1776         db_print_indent(indent);
1777         db_printf("rcv_adv: 0x%08x   rcv_wnd: %lu   rcv_up: 0x%08x\n",
1778             tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
1779
1780         db_print_indent(indent);
1781         db_printf("snd_wnd: %lu   snd_cwnd: %lu   snd_bwnd: %lu\n",
1782            tp->snd_wnd, tp->snd_cwnd, tp->snd_bwnd);
1783
1784         db_print_indent(indent);
1785         db_printf("snd_ssthresh: %lu   snd_bandwidth: %lu   snd_recover: "
1786             "0x%08x\n", tp->snd_ssthresh, tp->snd_bandwidth,
1787             tp->snd_recover);
1788
1789         db_print_indent(indent);
1790         db_printf("t_maxopd: %u   t_rcvtime: %lu   t_startime: %lu\n",
1791             tp->t_maxopd, tp->t_rcvtime, tp->t_starttime);
1792
1793         db_print_indent(indent);
1794         db_printf("t_rttime: %d   t_rtsq: 0x%08x   t_bw_rtttime: %d\n",
1795             tp->t_rtttime, tp->t_rtseq, tp->t_bw_rtttime);
1796
1797         db_print_indent(indent);
1798         db_printf("t_bw_rtseq: 0x%08x   t_rxtcur: %d   t_maxseg: %u   "
1799             "t_srtt: %d\n", tp->t_bw_rtseq, tp->t_rxtcur, tp->t_maxseg,
1800             tp->t_srtt);
1801
1802         db_print_indent(indent);
1803         db_printf("t_rttvar: %d   t_rxtshift: %d   t_rttmin: %u   "
1804             "t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
1805             tp->t_rttbest);
1806
1807         db_print_indent(indent);
1808         db_printf("t_rttupdated: %lu   max_sndwnd: %lu   t_softerror: %d\n",
1809             tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
1810
1811         db_print_indent(indent);
1812         db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
1813         db_print_toobflags(tp->t_oobflags);
1814         db_printf(")   t_iobc: 0x%02x\n", tp->t_iobc);
1815
1816         db_print_indent(indent);
1817         db_printf("snd_scale: %u   rcv_scale: %u   request_r_scale: %u\n",
1818             tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
1819
1820         db_print_indent(indent);
1821         db_printf("ts_recent: %u   ts_recent_age: %lu\n",
1822             tp->ts_recent, tp->ts_recent_age);
1823
1824         db_print_indent(indent);
1825         db_printf("ts_offset: %u   last_ack_sent: 0x%08x   snd_cwnd_prev: "
1826             "%lu\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
1827
1828         db_print_indent(indent);
1829         db_printf("snd_ssthresh_prev: %lu   snd_recover_prev: 0x%08x   "
1830             "t_badrxtwin: %lu\n", tp->snd_ssthresh_prev,
1831             tp->snd_recover_prev, tp->t_badrxtwin);
1832
1833         db_print_indent(indent);
1834         db_printf("snd_numholes: %d  snd_holes first: %p\n",
1835             tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
1836
1837         db_print_indent(indent);
1838         db_printf("snd_fack: 0x%08x   rcv_numsacks: %d   sack_newdata: "
1839             "0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
1840
1841         /* Skip sackblks, sackhint. */
1842
1843         db_print_indent(indent);
1844         db_printf("t_rttlow: %d   rfbuf_ts: %u   rfbuf_cnt: %d\n",
1845             tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
1846 }
1847
1848 DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
1849 {
1850         struct tcpcb *tp;
1851
1852         if (!have_addr) {
1853                 db_printf("usage: show tcpcb <addr>\n");
1854                 return;
1855         }
1856         tp = (struct tcpcb *)addr;
1857
1858         db_print_tcpcb(tp, "tcpcb", 0);
1859 }
1860 #endif