tcp_usrreq.c revision 1.65.2.1
1 /* $NetBSD: tcp_usrreq.c,v 1.65.2.1 2001/11/12 21:19:29 thorpej Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 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 * 3. Neither the name of the project 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 PROJECT 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 PROJECT 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 32 /*- 33 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Jason R. Thorpe and Kevin M. Lahey of the Numerical Aerospace Simulation 38 * Facility, NASA Ames Research Center. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1993, 1995 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. All advertising materials mentioning features or use of this software 82 * must display the following acknowledgement: 83 * This product includes software developed by the University of 84 * California, Berkeley and its contributors. 85 * 4. Neither the name of the University nor the names of its contributors 86 * may be used to endorse or promote products derived from this software 87 * without specific prior written permission. 88 * 89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 99 * SUCH DAMAGE. 100 * 101 * @(#)tcp_usrreq.c 8.5 (Berkeley) 6/21/95 102 */ 103 104 #include "opt_inet.h" 105 #include "opt_ipsec.h" 106 #include "opt_tcp_debug.h" 107 108 #include <sys/param.h> 109 #include <sys/systm.h> 110 #include <sys/kernel.h> 111 #include <sys/malloc.h> 112 #include <sys/mbuf.h> 113 #include <sys/socket.h> 114 #include <sys/socketvar.h> 115 #include <sys/protosw.h> 116 #include <sys/errno.h> 117 #include <sys/stat.h> 118 #include <sys/proc.h> 119 #include <sys/domain.h> 120 #include <sys/sysctl.h> 121 122 #include <net/if.h> 123 #include <net/route.h> 124 125 #include <netinet/in.h> 126 #include <netinet/in_systm.h> 127 #include <netinet/in_var.h> 128 #include <netinet/ip.h> 129 #include <netinet/in_pcb.h> 130 #include <netinet/ip_var.h> 131 132 #ifdef INET6 133 #ifndef INET 134 #include <netinet/in.h> 135 #endif 136 #include <netinet/ip6.h> 137 #include <netinet6/in6_pcb.h> 138 #include <netinet6/ip6_var.h> 139 #endif 140 141 #include <netinet/tcp.h> 142 #include <netinet/tcp_fsm.h> 143 #include <netinet/tcp_seq.h> 144 #include <netinet/tcp_timer.h> 145 #include <netinet/tcp_var.h> 146 #include <netinet/tcpip.h> 147 #include <netinet/tcp_debug.h> 148 149 #include "opt_tcp_recvspace.h" 150 #include "opt_tcp_sendspace.h" 151 152 #ifdef IPSEC 153 #include <netinet6/ipsec.h> 154 #endif /*IPSEC*/ 155 156 /* 157 * TCP protocol interface to socket abstraction. 158 */ 159 extern char *tcpstates[]; 160 161 /* 162 * Process a TCP user request for TCP tb. If this is a send request 163 * then m is the mbuf chain of send data. If this is a timer expiration 164 * (called from the software clock routine), then timertype tells which timer. 165 */ 166 /*ARGSUSED*/ 167 int 168 tcp_usrreq(so, req, m, nam, control, p) 169 struct socket *so; 170 int req; 171 struct mbuf *m, *nam, *control; 172 struct proc *p; 173 { 174 struct inpcb *inp; 175 #ifdef INET6 176 struct in6pcb *in6p; 177 #endif 178 struct tcpcb *tp = NULL; 179 int s; 180 int error = 0; 181 int ostate; 182 int family; /* family of the socket */ 183 184 family = so->so_proto->pr_domain->dom_family; 185 186 if (req == PRU_CONTROL) { 187 switch (family) { 188 #ifdef INET 189 case PF_INET: 190 return (in_control(so, (long)m, (caddr_t)nam, 191 (struct ifnet *)control, p)); 192 #endif 193 #ifdef INET6 194 case PF_INET6: 195 return (in6_control(so, (long)m, (caddr_t)nam, 196 (struct ifnet *)control, p)); 197 #endif 198 default: 199 return EAFNOSUPPORT; 200 } 201 } 202 203 if (req == PRU_PURGEIF) { 204 switch (family) { 205 #ifdef INET 206 case PF_INET: 207 in_pcbpurgeif0(&tcbtable, (struct ifnet *)control); 208 in_purgeif((struct ifnet *)control); 209 in_pcbpurgeif(&tcbtable, (struct ifnet *)control); 210 break; 211 #endif 212 #ifdef INET6 213 case PF_INET6: 214 in6_pcbpurgeif0(&tcb6, (struct ifnet *)control); 215 in6_purgeif((struct ifnet *)control); 216 in6_pcbpurgeif(&tcb6, (struct ifnet *)control); 217 break; 218 #endif 219 default: 220 return (EAFNOSUPPORT); 221 } 222 return (0); 223 } 224 225 s = splsoftnet(); 226 switch (family) { 227 #ifdef INET 228 case PF_INET: 229 inp = sotoinpcb(so); 230 #ifdef INET6 231 in6p = NULL; 232 #endif 233 break; 234 #endif 235 #ifdef INET6 236 case PF_INET6: 237 inp = NULL; 238 in6p = sotoin6pcb(so); 239 break; 240 #endif 241 default: 242 splx(s); 243 return EAFNOSUPPORT; 244 } 245 246 #ifdef DIAGNOSTIC 247 #ifdef INET6 248 if (inp && in6p) 249 panic("tcp_usrreq: both inp and in6p set to non-NULL"); 250 #endif 251 if (req != PRU_SEND && req != PRU_SENDOOB && control) 252 panic("tcp_usrreq: unexpected control mbuf"); 253 #endif 254 /* 255 * When a TCP is attached to a socket, then there will be 256 * a (struct inpcb) pointed at by the socket, and this 257 * structure will point at a subsidary (struct tcpcb). 258 */ 259 #ifndef INET6 260 if (inp == 0 && req != PRU_ATTACH) 261 #else 262 if ((inp == 0 && in6p == 0) && req != PRU_ATTACH) 263 #endif 264 { 265 error = EINVAL; 266 goto release; 267 } 268 #ifdef INET 269 if (inp) { 270 tp = intotcpcb(inp); 271 /* WHAT IF TP IS 0? */ 272 #ifdef KPROF 273 tcp_acounts[tp->t_state][req]++; 274 #endif 275 ostate = tp->t_state; 276 } 277 #endif 278 #ifdef INET6 279 if (in6p) { 280 tp = in6totcpcb(in6p); 281 /* WHAT IF TP IS 0? */ 282 #ifdef KPROF 283 tcp_acounts[tp->t_state][req]++; 284 #endif 285 ostate = tp->t_state; 286 } 287 #endif 288 else 289 ostate = 0; 290 291 switch (req) { 292 293 /* 294 * TCP attaches to socket via PRU_ATTACH, reserving space, 295 * and an internet control block. 296 */ 297 case PRU_ATTACH: 298 #ifndef INET6 299 if (inp != 0) 300 #else 301 if (inp != 0 || in6p != 0) 302 #endif 303 { 304 error = EISCONN; 305 break; 306 } 307 error = tcp_attach(so); 308 if (error) 309 break; 310 if ((so->so_options & SO_LINGER) && so->so_linger == 0) 311 so->so_linger = TCP_LINGERTIME; 312 tp = sototcpcb(so); 313 break; 314 315 /* 316 * PRU_DETACH detaches the TCP protocol from the socket. 317 */ 318 case PRU_DETACH: 319 tp = tcp_disconnect(tp); 320 break; 321 322 /* 323 * Give the socket an address. 324 */ 325 case PRU_BIND: 326 switch (family) { 327 #ifdef INET 328 case PF_INET: 329 error = in_pcbbind(inp, nam, p); 330 break; 331 #endif 332 #ifdef INET6 333 case PF_INET6: 334 error = in6_pcbbind(in6p, nam, p); 335 if (!error) { 336 /* mapped addr case */ 337 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)) 338 tp->t_family = AF_INET; 339 else 340 tp->t_family = AF_INET6; 341 } 342 break; 343 #endif 344 } 345 break; 346 347 /* 348 * Prepare to accept connections. 349 */ 350 case PRU_LISTEN: 351 #ifdef INET 352 if (inp && inp->inp_lport == 0) { 353 error = in_pcbbind(inp, (struct mbuf *)0, 354 (struct proc *)0); 355 if (error) 356 break; 357 } 358 #endif 359 #ifdef INET6 360 if (in6p && in6p->in6p_lport == 0) { 361 error = in6_pcbbind(in6p, (struct mbuf *)0, 362 (struct proc *)0); 363 if (error) 364 break; 365 } 366 #endif 367 tp->t_state = TCPS_LISTEN; 368 break; 369 370 /* 371 * Initiate connection to peer. 372 * Create a template for use in transmissions on this connection. 373 * Enter SYN_SENT state, and mark socket as connecting. 374 * Start keep-alive timer, and seed output sequence space. 375 * Send initial segment on connection. 376 */ 377 case PRU_CONNECT: 378 #ifdef INET 379 if (inp) { 380 if (inp->inp_lport == 0) { 381 error = in_pcbbind(inp, (struct mbuf *)0, 382 (struct proc *)0); 383 if (error) 384 break; 385 } 386 error = in_pcbconnect(inp, nam); 387 } 388 #endif 389 #ifdef INET6 390 if (in6p) { 391 if (in6p->in6p_lport == 0) { 392 error = in6_pcbbind(in6p, (struct mbuf *)0, 393 (struct proc *)0); 394 if (error) 395 break; 396 } 397 error = in6_pcbconnect(in6p, nam); 398 if (!error) { 399 /* mapped addr case */ 400 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) 401 tp->t_family = AF_INET; 402 else 403 tp->t_family = AF_INET6; 404 } 405 } 406 #endif 407 if (error) 408 break; 409 tp->t_template = tcp_template(tp); 410 if (tp->t_template == 0) { 411 #ifdef INET 412 if (inp) 413 in_pcbdisconnect(inp); 414 #endif 415 #ifdef INET6 416 if (in6p) 417 in6_pcbdisconnect(in6p); 418 #endif 419 error = ENOBUFS; 420 break; 421 } 422 /* Compute window scaling to request. */ 423 while (tp->request_r_scale < TCP_MAX_WINSHIFT && 424 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat) 425 tp->request_r_scale++; 426 soisconnecting(so); 427 tcpstat.tcps_connattempt++; 428 tp->t_state = TCPS_SYN_SENT; 429 TCP_TIMER_ARM(tp, TCPT_KEEP, TCPTV_KEEP_INIT); 430 tp->iss = tcp_new_iss(tp, 0); 431 tcp_sendseqinit(tp); 432 error = tcp_output(tp); 433 break; 434 435 /* 436 * Create a TCP connection between two sockets. 437 */ 438 case PRU_CONNECT2: 439 error = EOPNOTSUPP; 440 break; 441 442 /* 443 * Initiate disconnect from peer. 444 * If connection never passed embryonic stage, just drop; 445 * else if don't need to let data drain, then can just drop anyways, 446 * else have to begin TCP shutdown process: mark socket disconnecting, 447 * drain unread data, state switch to reflect user close, and 448 * send segment (e.g. FIN) to peer. Socket will be really disconnected 449 * when peer sends FIN and acks ours. 450 * 451 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB. 452 */ 453 case PRU_DISCONNECT: 454 tp = tcp_disconnect(tp); 455 break; 456 457 /* 458 * Accept a connection. Essentially all the work is 459 * done at higher levels; just return the address 460 * of the peer, storing through addr. 461 */ 462 case PRU_ACCEPT: 463 #ifdef INET 464 if (inp) 465 in_setpeeraddr(inp, nam); 466 #endif 467 #ifdef INET6 468 if (in6p) 469 in6_setpeeraddr(in6p, nam); 470 #endif 471 break; 472 473 /* 474 * Mark the connection as being incapable of further output. 475 */ 476 case PRU_SHUTDOWN: 477 socantsendmore(so); 478 tp = tcp_usrclosed(tp); 479 if (tp) 480 error = tcp_output(tp); 481 break; 482 483 /* 484 * After a receive, possibly send window update to peer. 485 */ 486 case PRU_RCVD: 487 /* 488 * soreceive() calls this function when a user receives 489 * ancillary data on a listening socket. We don't call 490 * tcp_output in such a case, since there is no header 491 * template for a listening socket and hence the kernel 492 * will panic. 493 */ 494 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) != 0) 495 (void) tcp_output(tp); 496 break; 497 498 /* 499 * Do a send by putting data in output queue and updating urgent 500 * marker if URG set. Possibly send more data. 501 */ 502 case PRU_SEND: 503 if (control && control->m_len) { 504 m_freem(control); 505 m_freem(m); 506 error = EINVAL; 507 break; 508 } 509 sbappend(&so->so_snd, m); 510 error = tcp_output(tp); 511 break; 512 513 /* 514 * Abort the TCP. 515 */ 516 case PRU_ABORT: 517 tp = tcp_drop(tp, ECONNABORTED); 518 break; 519 520 case PRU_SENSE: 521 /* 522 * stat: don't bother with a blocksize. 523 */ 524 splx(s); 525 return (0); 526 527 case PRU_RCVOOB: 528 if (control && control->m_len) { 529 m_freem(control); 530 m_freem(m); 531 error = EINVAL; 532 break; 533 } 534 if ((so->so_oobmark == 0 && 535 (so->so_state & SS_RCVATMARK) == 0) || 536 so->so_options & SO_OOBINLINE || 537 tp->t_oobflags & TCPOOB_HADDATA) { 538 error = EINVAL; 539 break; 540 } 541 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { 542 error = EWOULDBLOCK; 543 break; 544 } 545 m->m_len = 1; 546 *mtod(m, caddr_t) = tp->t_iobc; 547 if (((long)nam & MSG_PEEK) == 0) 548 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); 549 break; 550 551 case PRU_SENDOOB: 552 if (sbspace(&so->so_snd) < -512) { 553 m_freem(m); 554 error = ENOBUFS; 555 break; 556 } 557 /* 558 * According to RFC961 (Assigned Protocols), 559 * the urgent pointer points to the last octet 560 * of urgent data. We continue, however, 561 * to consider it to indicate the first octet 562 * of data past the urgent section. 563 * Otherwise, snd_up should be one lower. 564 */ 565 sbappend(&so->so_snd, m); 566 tp->snd_up = tp->snd_una + so->so_snd.sb_cc; 567 tp->t_force = 1; 568 error = tcp_output(tp); 569 tp->t_force = 0; 570 break; 571 572 case PRU_SOCKADDR: 573 #ifdef INET 574 if (inp) 575 in_setsockaddr(inp, nam); 576 #endif 577 #ifdef INET6 578 if (in6p) 579 in6_setsockaddr(in6p, nam); 580 #endif 581 break; 582 583 case PRU_PEERADDR: 584 #ifdef INET 585 if (inp) 586 in_setpeeraddr(inp, nam); 587 #endif 588 #ifdef INET6 589 if (in6p) 590 in6_setpeeraddr(in6p, nam); 591 #endif 592 break; 593 594 default: 595 panic("tcp_usrreq"); 596 } 597 #ifdef TCP_DEBUG 598 if (tp && (so->so_options & SO_DEBUG)) 599 tcp_trace(TA_USER, ostate, tp, NULL, req); 600 #endif 601 602 release: 603 splx(s); 604 return (error); 605 } 606 607 int 608 tcp_ctloutput(op, so, level, optname, mp) 609 int op; 610 struct socket *so; 611 int level, optname; 612 struct mbuf **mp; 613 { 614 int error = 0, s; 615 struct inpcb *inp; 616 #ifdef INET6 617 struct in6pcb *in6p; 618 #endif 619 struct tcpcb *tp; 620 struct mbuf *m; 621 int i; 622 int family; /* family of the socket */ 623 624 family = so->so_proto->pr_domain->dom_family; 625 626 s = splsoftnet(); 627 switch (family) { 628 #ifdef INET 629 case PF_INET: 630 inp = sotoinpcb(so); 631 #ifdef INET6 632 in6p = NULL; 633 #endif 634 break; 635 #endif 636 #ifdef INET6 637 case PF_INET6: 638 inp = NULL; 639 in6p = sotoin6pcb(so); 640 break; 641 #endif 642 default: 643 splx(s); 644 return EAFNOSUPPORT; 645 } 646 #ifndef INET6 647 if (inp == NULL) 648 #else 649 if (inp == NULL && in6p == NULL) 650 #endif 651 { 652 splx(s); 653 if (op == PRCO_SETOPT && *mp) 654 (void) m_free(*mp); 655 return (ECONNRESET); 656 } 657 if (level != IPPROTO_TCP) { 658 switch (family) { 659 #ifdef INET 660 case PF_INET: 661 error = ip_ctloutput(op, so, level, optname, mp); 662 break; 663 #endif 664 #ifdef INET6 665 case PF_INET6: 666 error = ip6_ctloutput(op, so, level, optname, mp); 667 break; 668 #endif 669 } 670 splx(s); 671 return (error); 672 } 673 if (inp) 674 tp = intotcpcb(inp); 675 #ifdef INET6 676 else if (in6p) 677 tp = in6totcpcb(in6p); 678 #endif 679 else 680 tp = NULL; 681 682 switch (op) { 683 684 case PRCO_SETOPT: 685 m = *mp; 686 switch (optname) { 687 688 case TCP_NODELAY: 689 if (m == NULL || m->m_len < sizeof (int)) 690 error = EINVAL; 691 else if (*mtod(m, int *)) 692 tp->t_flags |= TF_NODELAY; 693 else 694 tp->t_flags &= ~TF_NODELAY; 695 break; 696 697 case TCP_MAXSEG: 698 if (m && (i = *mtod(m, int *)) > 0 && 699 i <= tp->t_peermss) 700 tp->t_peermss = i; /* limit on send size */ 701 else 702 error = EINVAL; 703 break; 704 705 default: 706 error = ENOPROTOOPT; 707 break; 708 } 709 if (m) 710 (void) m_free(m); 711 break; 712 713 case PRCO_GETOPT: 714 *mp = m = m_get(M_WAIT, MT_SOOPTS); 715 m->m_len = sizeof(int); 716 717 switch (optname) { 718 case TCP_NODELAY: 719 *mtod(m, int *) = tp->t_flags & TF_NODELAY; 720 break; 721 case TCP_MAXSEG: 722 *mtod(m, int *) = tp->t_peermss; 723 break; 724 default: 725 error = ENOPROTOOPT; 726 break; 727 } 728 break; 729 } 730 splx(s); 731 return (error); 732 } 733 734 #ifndef TCP_SENDSPACE 735 #define TCP_SENDSPACE 1024*16; 736 #endif 737 int tcp_sendspace = TCP_SENDSPACE; 738 #ifndef TCP_RECVSPACE 739 #define TCP_RECVSPACE 1024*16; 740 #endif 741 int tcp_recvspace = TCP_RECVSPACE; 742 743 /* 744 * Attach TCP protocol to socket, allocating 745 * internet protocol control block, tcp control block, 746 * bufer space, and entering LISTEN state if to accept connections. 747 */ 748 int 749 tcp_attach(so) 750 struct socket *so; 751 { 752 struct tcpcb *tp; 753 struct inpcb *inp; 754 #ifdef INET6 755 struct in6pcb *in6p; 756 #endif 757 int error; 758 int family; /* family of the socket */ 759 760 family = so->so_proto->pr_domain->dom_family; 761 762 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 763 error = soreserve(so, tcp_sendspace, tcp_recvspace); 764 if (error) 765 return (error); 766 } 767 switch (family) { 768 #ifdef INET 769 case PF_INET: 770 error = in_pcballoc(so, &tcbtable); 771 if (error) 772 return (error); 773 inp = sotoinpcb(so); 774 #ifdef INET6 775 in6p = NULL; 776 #endif 777 break; 778 #endif 779 #ifdef INET6 780 case PF_INET6: 781 error = in6_pcballoc(so, &tcb6); 782 if (error) 783 return (error); 784 inp = NULL; 785 in6p = sotoin6pcb(so); 786 break; 787 #endif 788 default: 789 return EAFNOSUPPORT; 790 } 791 if (inp) 792 tp = tcp_newtcpcb(family, (void *)inp); 793 #ifdef INET6 794 else if (in6p) 795 tp = tcp_newtcpcb(family, (void *)in6p); 796 #endif 797 else 798 tp = NULL; 799 800 if (tp == 0) { 801 int nofd = so->so_state & SS_NOFDREF; /* XXX */ 802 803 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */ 804 #ifdef INET 805 if (inp) 806 in_pcbdetach(inp); 807 #endif 808 #ifdef INET6 809 if (in6p) 810 in6_pcbdetach(in6p); 811 #endif 812 so->so_state |= nofd; 813 return (ENOBUFS); 814 } 815 tp->t_state = TCPS_CLOSED; 816 return (0); 817 } 818 819 /* 820 * Initiate (or continue) disconnect. 821 * If embryonic state, just send reset (once). 822 * If in ``let data drain'' option and linger null, just drop. 823 * Otherwise (hard), mark socket disconnecting and drop 824 * current input data; switch states based on user close, and 825 * send segment to peer (with FIN). 826 */ 827 struct tcpcb * 828 tcp_disconnect(tp) 829 struct tcpcb *tp; 830 { 831 struct socket *so; 832 833 if (tp->t_inpcb) 834 so = tp->t_inpcb->inp_socket; 835 #ifdef INET6 836 else if (tp->t_in6pcb) 837 so = tp->t_in6pcb->in6p_socket; 838 #endif 839 else 840 so = NULL; 841 842 if (TCPS_HAVEESTABLISHED(tp->t_state) == 0) 843 tp = tcp_close(tp); 844 else if ((so->so_options & SO_LINGER) && so->so_linger == 0) 845 tp = tcp_drop(tp, 0); 846 else { 847 soisdisconnecting(so); 848 sbflush(&so->so_rcv); 849 tp = tcp_usrclosed(tp); 850 if (tp) 851 (void) tcp_output(tp); 852 } 853 return (tp); 854 } 855 856 /* 857 * User issued close, and wish to trail through shutdown states: 858 * if never received SYN, just forget it. If got a SYN from peer, 859 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. 860 * If already got a FIN from peer, then almost done; go to LAST_ACK 861 * state. In all other cases, have already sent FIN to peer (e.g. 862 * after PRU_SHUTDOWN), and just have to play tedious game waiting 863 * for peer to send FIN or not respond to keep-alives, etc. 864 * We can let the user exit from the close as soon as the FIN is acked. 865 */ 866 struct tcpcb * 867 tcp_usrclosed(tp) 868 struct tcpcb *tp; 869 { 870 871 switch (tp->t_state) { 872 873 case TCPS_CLOSED: 874 case TCPS_LISTEN: 875 case TCPS_SYN_SENT: 876 tp->t_state = TCPS_CLOSED; 877 tp = tcp_close(tp); 878 break; 879 880 case TCPS_SYN_RECEIVED: 881 case TCPS_ESTABLISHED: 882 tp->t_state = TCPS_FIN_WAIT_1; 883 break; 884 885 case TCPS_CLOSE_WAIT: 886 tp->t_state = TCPS_LAST_ACK; 887 break; 888 } 889 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) { 890 struct socket *so; 891 if (tp->t_inpcb) 892 so = tp->t_inpcb->inp_socket; 893 #ifdef INET6 894 else if (tp->t_in6pcb) 895 so = tp->t_in6pcb->in6p_socket; 896 #endif 897 else 898 so = NULL; 899 soisdisconnected(so); 900 /* 901 * If we are in FIN_WAIT_2, we arrived here because the 902 * application did a shutdown of the send side. Like the 903 * case of a transition from FIN_WAIT_1 to FIN_WAIT_2 after 904 * a full close, we start a timer to make sure sockets are 905 * not left in FIN_WAIT_2 forever. 906 */ 907 if ((tp->t_state == TCPS_FIN_WAIT_2) && (tcp_maxidle > 0)) 908 TCP_TIMER_ARM(tp, TCPT_2MSL, tcp_maxidle); 909 } 910 return (tp); 911 } 912 913 static const struct { 914 unsigned int valid : 1; 915 unsigned int rdonly : 1; 916 int *var; 917 int val; 918 } tcp_ctlvars[] = TCPCTL_VARIABLES; 919 920 /* 921 * Sysctl for tcp variables. 922 */ 923 int 924 tcp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 925 int *name; 926 u_int namelen; 927 void *oldp; 928 size_t *oldlenp; 929 void *newp; 930 size_t newlen; 931 { 932 933 /* All sysctl names at this level are terminal. */ 934 if (namelen != 1) 935 return (ENOTDIR); 936 937 if (name[0] < sizeof(tcp_ctlvars)/sizeof(tcp_ctlvars[0]) 938 && tcp_ctlvars[name[0]].valid) { 939 if (tcp_ctlvars[name[0]].rdonly) 940 return (sysctl_rdint(oldp, oldlenp, newp, 941 tcp_ctlvars[name[0]].val)); 942 else 943 return (sysctl_int(oldp, oldlenp, newp, newlen, 944 tcp_ctlvars[name[0]].var)); 945 } 946 947 return (ENOPROTOOPT); 948 } 949
Indexes created Sun Sep 21 20:09:37 GMT 2025