tcp_usrreq.c revision 1.58
1 /* $NetBSD: tcp_usrreq.c,v 1.58 2000/12/11 00:07:48 itojun 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" 106 107 #include <sys/param.h> 108 #include <sys/systm.h> 109 #include <sys/kernel.h> 110 #include <sys/malloc.h> 111 #include <sys/mbuf.h> 112 #include <sys/socket.h> 113 #include <sys/socketvar.h> 114 #include <sys/protosw.h> 115 #include <sys/errno.h> 116 #include <sys/stat.h> 117 #include <sys/proc.h> 118 #include <sys/ucred.h> 119 #include <sys/domain.h> 120 121 #include <uvm/uvm_extern.h> 122 #include <sys/sysctl.h> 123 124 #include <net/if.h> 125 #include <net/route.h> 126 127 #include <netinet/in.h> 128 #include <netinet/in_systm.h> 129 #include <netinet/in_var.h> 130 #include <netinet/ip.h> 131 #include <netinet/in_pcb.h> 132 #include <netinet/ip_var.h> 133 134 #ifdef INET6 135 #ifndef INET 136 #include <netinet/in.h> 137 #endif 138 #include <netinet/ip6.h> 139 #include <netinet6/in6_pcb.h> 140 #include <netinet6/ip6_var.h> 141 #endif 142 143 #include <netinet/tcp.h> 144 #include <netinet/tcp_fsm.h> 145 #include <netinet/tcp_seq.h> 146 #include <netinet/tcp_timer.h> 147 #include <netinet/tcp_var.h> 148 #include <netinet/tcpip.h> 149 #include <netinet/tcp_debug.h> 150 151 #include "opt_tcp_recvspace.h" 152 #include "opt_tcp_sendspace.h" 153 154 #ifdef IPSEC 155 #include <netinet6/ipsec.h> 156 #endif /*IPSEC*/ 157 158 /* 159 * TCP protocol interface to socket abstraction. 160 */ 161 extern char *tcpstates[]; 162 163 /* 164 * Process a TCP user request for TCP tb. If this is a send request 165 * then m is the mbuf chain of send data. If this is a timer expiration 166 * (called from the software clock routine), then timertype tells which timer. 167 */ 168 /*ARGSUSED*/ 169 int 170 tcp_usrreq(so, req, m, nam, control, p) 171 struct socket *so; 172 int req; 173 struct mbuf *m, *nam, *control; 174 struct proc *p; 175 { 176 struct inpcb *inp; 177 #ifdef INET6 178 struct in6pcb *in6p; 179 #endif 180 struct tcpcb *tp = NULL; 181 int s; 182 int error = 0; 183 int ostate; 184 int family; /* family of the socket */ 185 186 family = so->so_proto->pr_domain->dom_family; 187 188 if (req == PRU_CONTROL) { 189 switch (family) { 190 #ifdef INET 191 case PF_INET: 192 return (in_control(so, (long)m, (caddr_t)nam, 193 (struct ifnet *)control, p)); 194 #endif 195 #ifdef INET6 196 case PF_INET6: 197 return (in6_control(so, (long)m, (caddr_t)nam, 198 (struct ifnet *)control, p)); 199 #endif 200 default: 201 return EAFNOSUPPORT; 202 } 203 } 204 205 if (req == PRU_PURGEIF) { 206 switch (family) { 207 #ifdef INET 208 case PF_INET: 209 in_purgeif((struct ifnet *)control); 210 in_pcbpurgeif(&tcbtable, (struct ifnet *)control); 211 break; 212 #endif 213 #ifdef INET6 214 case PF_INET6: 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, sizeof(struct tcpcb), 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 (void) tcp_output(tp); 488 break; 489 490 /* 491 * Do a send by putting data in output queue and updating urgent 492 * marker if URG set. Possibly send more data. 493 */ 494 case PRU_SEND: 495 if (control && control->m_len) { 496 m_freem(control); 497 m_freem(m); 498 error = EINVAL; 499 break; 500 } 501 sbappend(&so->so_snd, m); 502 error = tcp_output(tp); 503 break; 504 505 /* 506 * Abort the TCP. 507 */ 508 case PRU_ABORT: 509 tp = tcp_drop(tp, ECONNABORTED); 510 break; 511 512 case PRU_SENSE: 513 /* 514 * stat: don't bother with a blocksize. 515 */ 516 splx(s); 517 return (0); 518 519 case PRU_RCVOOB: 520 if (control && control->m_len) { 521 m_freem(control); 522 m_freem(m); 523 error = EINVAL; 524 break; 525 } 526 if ((so->so_oobmark == 0 && 527 (so->so_state & SS_RCVATMARK) == 0) || 528 so->so_options & SO_OOBINLINE || 529 tp->t_oobflags & TCPOOB_HADDATA) { 530 error = EINVAL; 531 break; 532 } 533 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { 534 error = EWOULDBLOCK; 535 break; 536 } 537 m->m_len = 1; 538 *mtod(m, caddr_t) = tp->t_iobc; 539 if (((long)nam & MSG_PEEK) == 0) 540 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); 541 break; 542 543 case PRU_SENDOOB: 544 if (sbspace(&so->so_snd) < -512) { 545 m_freem(m); 546 error = ENOBUFS; 547 break; 548 } 549 /* 550 * According to RFC961 (Assigned Protocols), 551 * the urgent pointer points to the last octet 552 * of urgent data. We continue, however, 553 * to consider it to indicate the first octet 554 * of data past the urgent section. 555 * Otherwise, snd_up should be one lower. 556 */ 557 sbappend(&so->so_snd, m); 558 tp->snd_up = tp->snd_una + so->so_snd.sb_cc; 559 tp->t_force = 1; 560 error = tcp_output(tp); 561 tp->t_force = 0; 562 break; 563 564 case PRU_SOCKADDR: 565 #ifdef INET 566 if (inp) 567 in_setsockaddr(inp, nam); 568 #endif 569 #ifdef INET6 570 if (in6p) 571 in6_setsockaddr(in6p, nam); 572 #endif 573 break; 574 575 case PRU_PEERADDR: 576 #ifdef INET 577 if (inp) 578 in_setpeeraddr(inp, nam); 579 #endif 580 #ifdef INET6 581 if (in6p) 582 in6_setpeeraddr(in6p, nam); 583 #endif 584 break; 585 586 /* 587 * TCP slow timer went off; going through this 588 * routine for tracing's sake. 589 */ 590 case PRU_SLOWTIMO: 591 tp = tcp_timers(tp, (long)nam); 592 req |= (long)nam << 8; /* for debug's sake */ 593 break; 594 595 default: 596 panic("tcp_usrreq"); 597 } 598 if (tp && (so->so_options & SO_DEBUG)) 599 tcp_trace(TA_USER, ostate, tp, NULL, req); 600 601 release: 602 splx(s); 603 return (error); 604 } 605 606 int 607 tcp_ctloutput(op, so, level, optname, mp) 608 int op; 609 struct socket *so; 610 int level, optname; 611 struct mbuf **mp; 612 { 613 int error = 0, s; 614 struct inpcb *inp; 615 #ifdef INET6 616 struct in6pcb *in6p; 617 #endif 618 struct tcpcb *tp; 619 struct mbuf *m; 620 int i; 621 int family; /* family of the socket */ 622 623 family = so->so_proto->pr_domain->dom_family; 624 625 s = splsoftnet(); 626 switch (family) { 627 #ifdef INET 628 case PF_INET: 629 inp = sotoinpcb(so); 630 #ifdef INET6 631 in6p = NULL; 632 #endif 633 break; 634 #endif 635 #ifdef INET6 636 case PF_INET6: 637 inp = NULL; 638 in6p = sotoin6pcb(so); 639 break; 640 #endif 641 default: 642 splx(s); 643 return EAFNOSUPPORT; 644 } 645 #ifndef INET6 646 if (inp == NULL) 647 #else 648 if (inp == NULL && in6p == NULL) 649 #endif 650 { 651 splx(s); 652 if (op == PRCO_SETOPT && *mp) 653 (void) m_free(*mp); 654 return (ECONNRESET); 655 } 656 if (level != IPPROTO_TCP) { 657 switch (family) { 658 #ifdef INET 659 case PF_INET: 660 error = ip_ctloutput(op, so, level, optname, mp); 661 break; 662 #endif 663 #ifdef INET6 664 case PF_INET6: 665 error = ip6_ctloutput(op, so, level, optname, mp); 666 break; 667 #endif 668 } 669 splx(s); 670 return (error); 671 } 672 if (inp) 673 tp = intotcpcb(inp); 674 #ifdef INET6 675 else if (in6p) 676 tp = in6totcpcb(in6p); 677 #endif 678 else 679 tp = NULL; 680 681 switch (op) { 682 683 case PRCO_SETOPT: 684 m = *mp; 685 switch (optname) { 686 687 case TCP_NODELAY: 688 if (m == NULL || m->m_len < sizeof (int)) 689 error = EINVAL; 690 else if (*mtod(m, int *)) 691 tp->t_flags |= TF_NODELAY; 692 else 693 tp->t_flags &= ~TF_NODELAY; 694 break; 695 696 case TCP_MAXSEG: 697 if (m && (i = *mtod(m, int *)) > 0 && 698 i <= tp->t_peermss) 699 tp->t_peermss = i; /* limit on send size */ 700 else 701 error = EINVAL; 702 break; 703 704 default: 705 error = ENOPROTOOPT; 706 break; 707 } 708 if (m) 709 (void) m_free(m); 710 break; 711 712 case PRCO_GETOPT: 713 *mp = m = m_get(M_WAIT, MT_SOOPTS); 714 m->m_len = sizeof(int); 715 716 switch (optname) { 717 case TCP_NODELAY: 718 *mtod(m, int *) = tp->t_flags & TF_NODELAY; 719 break; 720 case TCP_MAXSEG: 721 *mtod(m, int *) = tp->t_peermss; 722 break; 723 default: 724 error = ENOPROTOOPT; 725 break; 726 } 727 break; 728 } 729 splx(s); 730 return (error); 731 } 732 733 #ifndef TCP_SENDSPACE 734 #define TCP_SENDSPACE 1024*16; 735 #endif 736 int tcp_sendspace = TCP_SENDSPACE; 737 #ifndef TCP_RECVSPACE 738 #define TCP_RECVSPACE 1024*16; 739 #endif 740 int tcp_recvspace = TCP_RECVSPACE; 741 742 /* 743 * Attach TCP protocol to socket, allocating 744 * internet protocol control block, tcp control block, 745 * bufer space, and entering LISTEN state if to accept connections. 746 */ 747 int 748 tcp_attach(so) 749 struct socket *so; 750 { 751 struct tcpcb *tp; 752 struct inpcb *inp; 753 #ifdef INET6 754 struct in6pcb *in6p; 755 #endif 756 int error; 757 int family; /* family of the socket */ 758 759 family = so->so_proto->pr_domain->dom_family; 760 761 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 762 error = soreserve(so, tcp_sendspace, tcp_recvspace); 763 if (error) 764 return (error); 765 } 766 switch (family) { 767 #ifdef INET 768 case PF_INET: 769 error = in_pcballoc(so, &tcbtable); 770 if (error) 771 return (error); 772 inp = sotoinpcb(so); 773 #ifdef INET6 774 in6p = NULL; 775 #endif 776 break; 777 #endif 778 #ifdef INET6 779 case PF_INET6: 780 error = in6_pcballoc(so, &tcb6); 781 if (error) 782 return (error); 783 inp = NULL; 784 in6p = sotoin6pcb(so); 785 break; 786 #endif 787 default: 788 return EAFNOSUPPORT; 789 } 790 #ifdef IPSEC 791 #ifdef INET 792 if (inp) { 793 error = ipsec_init_policy(so, &inp->inp_sp); 794 if (error != 0) { 795 in_pcbdetach(inp); 796 return (error); 797 } 798 } 799 #endif 800 #ifdef INET6 801 if (in6p) { 802 error = ipsec_init_policy(so, &in6p->in6p_sp); 803 if (error != 0) { 804 in6_pcbdetach(in6p); 805 return (error); 806 } 807 } 808 #endif 809 #endif /*IPSEC*/ 810 if (inp) 811 tp = tcp_newtcpcb(family, (void *)inp); 812 #ifdef INET6 813 else if (in6p) 814 tp = tcp_newtcpcb(family, (void *)in6p); 815 #endif 816 else 817 tp = NULL; 818 819 if (tp == 0) { 820 int nofd = so->so_state & SS_NOFDREF; /* XXX */ 821 822 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */ 823 #ifdef INET 824 if (inp) 825 in_pcbdetach(inp); 826 #endif 827 #ifdef INET6 828 if (in6p) 829 in6_pcbdetach(in6p); 830 #endif 831 so->so_state |= nofd; 832 return (ENOBUFS); 833 } 834 tp->t_state = TCPS_CLOSED; 835 return (0); 836 } 837 838 /* 839 * Initiate (or continue) disconnect. 840 * If embryonic state, just send reset (once). 841 * If in ``let data drain'' option and linger null, just drop. 842 * Otherwise (hard), mark socket disconnecting and drop 843 * current input data; switch states based on user close, and 844 * send segment to peer (with FIN). 845 */ 846 struct tcpcb * 847 tcp_disconnect(tp) 848 struct tcpcb *tp; 849 { 850 struct socket *so; 851 852 if (tp->t_inpcb) 853 so = tp->t_inpcb->inp_socket; 854 #ifdef INET6 855 else if (tp->t_in6pcb) 856 so = tp->t_in6pcb->in6p_socket; 857 #endif 858 else 859 so = NULL; 860 861 if (TCPS_HAVEESTABLISHED(tp->t_state) == 0) 862 tp = tcp_close(tp); 863 else if ((so->so_options & SO_LINGER) && so->so_linger == 0) 864 tp = tcp_drop(tp, 0); 865 else { 866 soisdisconnecting(so); 867 sbflush(&so->so_rcv); 868 tp = tcp_usrclosed(tp); 869 if (tp) 870 (void) tcp_output(tp); 871 } 872 return (tp); 873 } 874 875 /* 876 * User issued close, and wish to trail through shutdown states: 877 * if never received SYN, just forget it. If got a SYN from peer, 878 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. 879 * If already got a FIN from peer, then almost done; go to LAST_ACK 880 * state. In all other cases, have already sent FIN to peer (e.g. 881 * after PRU_SHUTDOWN), and just have to play tedious game waiting 882 * for peer to send FIN or not respond to keep-alives, etc. 883 * We can let the user exit from the close as soon as the FIN is acked. 884 */ 885 struct tcpcb * 886 tcp_usrclosed(tp) 887 struct tcpcb *tp; 888 { 889 890 switch (tp->t_state) { 891 892 case TCPS_CLOSED: 893 case TCPS_LISTEN: 894 case TCPS_SYN_SENT: 895 tp->t_state = TCPS_CLOSED; 896 tp = tcp_close(tp); 897 break; 898 899 case TCPS_SYN_RECEIVED: 900 case TCPS_ESTABLISHED: 901 tp->t_state = TCPS_FIN_WAIT_1; 902 break; 903 904 case TCPS_CLOSE_WAIT: 905 tp->t_state = TCPS_LAST_ACK; 906 break; 907 } 908 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) { 909 struct socket *so; 910 if (tp->t_inpcb) 911 so = tp->t_inpcb->inp_socket; 912 #ifdef INET6 913 else if (tp->t_in6pcb) 914 so = tp->t_in6pcb->in6p_socket; 915 #endif 916 else 917 so = NULL; 918 soisdisconnected(so); 919 /* 920 * If we are in FIN_WAIT_2, we arrived here because the 921 * application did a shutdown of the send side. Like the 922 * case of a transition from FIN_WAIT_1 to FIN_WAIT_2 after 923 * a full close, we start a timer to make sure sockets are 924 * not left in FIN_WAIT_2 forever. 925 */ 926 if ((tp->t_state == TCPS_FIN_WAIT_2) && (tcp_maxidle > 0)) 927 TCP_TIMER_ARM(tp, TCPT_2MSL, tcp_maxidle); 928 } 929 return (tp); 930 } 931 932 static struct { 933 unsigned int valid : 1; 934 unsigned int rdonly : 1; 935 int *var; 936 int val; 937 } tcp_ctlvars[] = TCPCTL_VARIABLES; 938 939 /* 940 * Sysctl for tcp variables. 941 */ 942 int 943 tcp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 944 int *name; 945 u_int namelen; 946 void *oldp; 947 size_t *oldlenp; 948 void *newp; 949 size_t newlen; 950 { 951 952 /* All sysctl names at this level are terminal. */ 953 if (namelen != 1) 954 return (ENOTDIR); 955 956 if (name[0] < sizeof(tcp_ctlvars)/sizeof(tcp_ctlvars[0]) 957 && tcp_ctlvars[name[0]].valid) { 958 if (tcp_ctlvars[name[0]].rdonly) 959 return (sysctl_rdint(oldp, oldlenp, newp, 960 tcp_ctlvars[name[0]].val)); 961 else 962 return (sysctl_int(oldp, oldlenp, newp, newlen, 963 tcp_ctlvars[name[0]].var)); 964 } 965 966 return (ENOPROTOOPT); 967 } 968
Indexes created Sun Sep 21 20:09:37 GMT 2025