tcp_usrreq.c revision 1.60.2.3
1 /* $NetBSD: tcp_usrreq.c,v 1.60.2.3 2001/09/21 22:36:51 nathanw 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/ucred.h> 120 #include <sys/domain.h> 121 122 #include <uvm/uvm_extern.h> 123 #include <sys/sysctl.h> 124 125 #include <net/if.h> 126 #include <net/route.h> 127 128 #include <netinet/in.h> 129 #include <netinet/in_systm.h> 130 #include <netinet/in_var.h> 131 #include <netinet/ip.h> 132 #include <netinet/in_pcb.h> 133 #include <netinet/ip_var.h> 134 135 #ifdef INET6 136 #ifndef INET 137 #include <netinet/in.h> 138 #endif 139 #include <netinet/ip6.h> 140 #include <netinet6/in6_pcb.h> 141 #include <netinet6/ip6_var.h> 142 #endif 143 144 #include <netinet/tcp.h> 145 #include <netinet/tcp_fsm.h> 146 #include <netinet/tcp_seq.h> 147 #include <netinet/tcp_timer.h> 148 #include <netinet/tcp_var.h> 149 #include <netinet/tcpip.h> 150 #include <netinet/tcp_debug.h> 151 152 #include "opt_tcp_recvspace.h" 153 #include "opt_tcp_sendspace.h" 154 155 #ifdef IPSEC 156 #include <netinet6/ipsec.h> 157 #endif /*IPSEC*/ 158 159 /* 160 * TCP protocol interface to socket abstraction. 161 */ 162 extern char *tcpstates[]; 163 164 /* 165 * Process a TCP user request for TCP tb. If this is a send request 166 * then m is the mbuf chain of send data. If this is a timer expiration 167 * (called from the software clock routine), then timertype tells which timer. 168 */ 169 /*ARGSUSED*/ 170 int 171 tcp_usrreq(so, req, m, nam, control, p) 172 struct socket *so; 173 int req; 174 struct mbuf *m, *nam, *control; 175 struct proc *p; 176 { 177 struct inpcb *inp; 178 #ifdef INET6 179 struct in6pcb *in6p; 180 #endif 181 struct tcpcb *tp = NULL; 182 int s; 183 int error = 0; 184 int ostate; 185 int family; /* family of the socket */ 186 187 family = so->so_proto->pr_domain->dom_family; 188 189 if (req == PRU_CONTROL) { 190 switch (family) { 191 #ifdef INET 192 case PF_INET: 193 return (in_control(so, (long)m, (caddr_t)nam, 194 (struct ifnet *)control, p)); 195 #endif 196 #ifdef INET6 197 case PF_INET6: 198 return (in6_control(so, (long)m, (caddr_t)nam, 199 (struct ifnet *)control, p)); 200 #endif 201 default: 202 return EAFNOSUPPORT; 203 } 204 } 205 206 if (req == PRU_PURGEIF) { 207 switch (family) { 208 #ifdef INET 209 case PF_INET: 210 in_pcbpurgeif0(&tcbtable, (struct ifnet *)control); 211 in_purgeif((struct ifnet *)control); 212 in_pcbpurgeif(&tcbtable, (struct ifnet *)control); 213 break; 214 #endif 215 #ifdef INET6 216 case PF_INET6: 217 in6_pcbpurgeif0(&tcb6, (struct ifnet *)control); 218 in6_purgeif((struct ifnet *)control); 219 in6_pcbpurgeif(&tcb6, (struct ifnet *)control); 220 break; 221 #endif 222 default: 223 return (EAFNOSUPPORT); 224 } 225 return (0); 226 } 227 228 s = splsoftnet(); 229 switch (family) { 230 #ifdef INET 231 case PF_INET: 232 inp = sotoinpcb(so); 233 #ifdef INET6 234 in6p = NULL; 235 #endif 236 break; 237 #endif 238 #ifdef INET6 239 case PF_INET6: 240 inp = NULL; 241 in6p = sotoin6pcb(so); 242 break; 243 #endif 244 default: 245 splx(s); 246 return EAFNOSUPPORT; 247 } 248 249 #ifdef DIAGNOSTIC 250 #ifdef INET6 251 if (inp && in6p) 252 panic("tcp_usrreq: both inp and in6p set to non-NULL"); 253 #endif 254 if (req != PRU_SEND && req != PRU_SENDOOB && control) 255 panic("tcp_usrreq: unexpected control mbuf"); 256 #endif 257 /* 258 * When a TCP is attached to a socket, then there will be 259 * a (struct inpcb) pointed at by the socket, and this 260 * structure will point at a subsidary (struct tcpcb). 261 */ 262 #ifndef INET6 263 if (inp == 0 && req != PRU_ATTACH) 264 #else 265 if ((inp == 0 && in6p == 0) && req != PRU_ATTACH) 266 #endif 267 { 268 error = EINVAL; 269 goto release; 270 } 271 #ifdef INET 272 if (inp) { 273 tp = intotcpcb(inp); 274 /* WHAT IF TP IS 0? */ 275 #ifdef KPROF 276 tcp_acounts[tp->t_state][req]++; 277 #endif 278 ostate = tp->t_state; 279 } 280 #endif 281 #ifdef INET6 282 if (in6p) { 283 tp = in6totcpcb(in6p); 284 /* WHAT IF TP IS 0? */ 285 #ifdef KPROF 286 tcp_acounts[tp->t_state][req]++; 287 #endif 288 ostate = tp->t_state; 289 } 290 #endif 291 else 292 ostate = 0; 293 294 switch (req) { 295 296 /* 297 * TCP attaches to socket via PRU_ATTACH, reserving space, 298 * and an internet control block. 299 */ 300 case PRU_ATTACH: 301 #ifndef INET6 302 if (inp != 0) 303 #else 304 if (inp != 0 || in6p != 0) 305 #endif 306 { 307 error = EISCONN; 308 break; 309 } 310 error = tcp_attach(so); 311 if (error) 312 break; 313 if ((so->so_options & SO_LINGER) && so->so_linger == 0) 314 so->so_linger = TCP_LINGERTIME; 315 tp = sototcpcb(so); 316 break; 317 318 /* 319 * PRU_DETACH detaches the TCP protocol from the socket. 320 */ 321 case PRU_DETACH: 322 tp = tcp_disconnect(tp); 323 break; 324 325 /* 326 * Give the socket an address. 327 */ 328 case PRU_BIND: 329 switch (family) { 330 #ifdef INET 331 case PF_INET: 332 error = in_pcbbind(inp, nam, p); 333 break; 334 #endif 335 #ifdef INET6 336 case PF_INET6: 337 error = in6_pcbbind(in6p, nam, p); 338 if (!error) { 339 /* mapped addr case */ 340 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)) 341 tp->t_family = AF_INET; 342 else 343 tp->t_family = AF_INET6; 344 } 345 break; 346 #endif 347 } 348 break; 349 350 /* 351 * Prepare to accept connections. 352 */ 353 case PRU_LISTEN: 354 #ifdef INET 355 if (inp && inp->inp_lport == 0) { 356 error = in_pcbbind(inp, (struct mbuf *)0, 357 (struct proc *)0); 358 if (error) 359 break; 360 } 361 #endif 362 #ifdef INET6 363 if (in6p && in6p->in6p_lport == 0) { 364 error = in6_pcbbind(in6p, (struct mbuf *)0, 365 (struct proc *)0); 366 if (error) 367 break; 368 } 369 #endif 370 tp->t_state = TCPS_LISTEN; 371 break; 372 373 /* 374 * Initiate connection to peer. 375 * Create a template for use in transmissions on this connection. 376 * Enter SYN_SENT state, and mark socket as connecting. 377 * Start keep-alive timer, and seed output sequence space. 378 * Send initial segment on connection. 379 */ 380 case PRU_CONNECT: 381 #ifdef INET 382 if (inp) { 383 if (inp->inp_lport == 0) { 384 error = in_pcbbind(inp, (struct mbuf *)0, 385 (struct proc *)0); 386 if (error) 387 break; 388 } 389 error = in_pcbconnect(inp, nam); 390 } 391 #endif 392 #ifdef INET6 393 if (in6p) { 394 if (in6p->in6p_lport == 0) { 395 error = in6_pcbbind(in6p, (struct mbuf *)0, 396 (struct proc *)0); 397 if (error) 398 break; 399 } 400 error = in6_pcbconnect(in6p, nam); 401 if (!error) { 402 /* mapped addr case */ 403 if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) 404 tp->t_family = AF_INET; 405 else 406 tp->t_family = AF_INET6; 407 } 408 } 409 #endif 410 if (error) 411 break; 412 tp->t_template = tcp_template(tp); 413 if (tp->t_template == 0) { 414 #ifdef INET 415 if (inp) 416 in_pcbdisconnect(inp); 417 #endif 418 #ifdef INET6 419 if (in6p) 420 in6_pcbdisconnect(in6p); 421 #endif 422 error = ENOBUFS; 423 break; 424 } 425 /* Compute window scaling to request. */ 426 while (tp->request_r_scale < TCP_MAX_WINSHIFT && 427 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat) 428 tp->request_r_scale++; 429 soisconnecting(so); 430 tcpstat.tcps_connattempt++; 431 tp->t_state = TCPS_SYN_SENT; 432 TCP_TIMER_ARM(tp, TCPT_KEEP, TCPTV_KEEP_INIT); 433 tp->iss = tcp_new_iss(tp, 0); 434 tcp_sendseqinit(tp); 435 error = tcp_output(tp); 436 break; 437 438 /* 439 * Create a TCP connection between two sockets. 440 */ 441 case PRU_CONNECT2: 442 error = EOPNOTSUPP; 443 break; 444 445 /* 446 * Initiate disconnect from peer. 447 * If connection never passed embryonic stage, just drop; 448 * else if don't need to let data drain, then can just drop anyways, 449 * else have to begin TCP shutdown process: mark socket disconnecting, 450 * drain unread data, state switch to reflect user close, and 451 * send segment (e.g. FIN) to peer. Socket will be really disconnected 452 * when peer sends FIN and acks ours. 453 * 454 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB. 455 */ 456 case PRU_DISCONNECT: 457 tp = tcp_disconnect(tp); 458 break; 459 460 /* 461 * Accept a connection. Essentially all the work is 462 * done at higher levels; just return the address 463 * of the peer, storing through addr. 464 */ 465 case PRU_ACCEPT: 466 #ifdef INET 467 if (inp) 468 in_setpeeraddr(inp, nam); 469 #endif 470 #ifdef INET6 471 if (in6p) 472 in6_setpeeraddr(in6p, nam); 473 #endif 474 break; 475 476 /* 477 * Mark the connection as being incapable of further output. 478 */ 479 case PRU_SHUTDOWN: 480 socantsendmore(so); 481 tp = tcp_usrclosed(tp); 482 if (tp) 483 error = tcp_output(tp); 484 break; 485 486 /* 487 * After a receive, possibly send window update to peer. 488 */ 489 case PRU_RCVD: 490 /* 491 * soreceive() calls this function when a user receives 492 * ancillary data on a listening socket. We don't call 493 * tcp_output in such a case, since there is no header 494 * template for a listening socket and hence the kernel 495 * will panic. 496 */ 497 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) != 0) 498 (void) tcp_output(tp); 499 break; 500 501 /* 502 * Do a send by putting data in output queue and updating urgent 503 * marker if URG set. Possibly send more data. 504 */ 505 case PRU_SEND: 506 if (control && control->m_len) { 507 m_freem(control); 508 m_freem(m); 509 error = EINVAL; 510 break; 511 } 512 sbappend(&so->so_snd, m); 513 error = tcp_output(tp); 514 break; 515 516 /* 517 * Abort the TCP. 518 */ 519 case PRU_ABORT: 520 tp = tcp_drop(tp, ECONNABORTED); 521 break; 522 523 case PRU_SENSE: 524 /* 525 * stat: don't bother with a blocksize. 526 */ 527 splx(s); 528 return (0); 529 530 case PRU_RCVOOB: 531 if (control && control->m_len) { 532 m_freem(control); 533 m_freem(m); 534 error = EINVAL; 535 break; 536 } 537 if ((so->so_oobmark == 0 && 538 (so->so_state & SS_RCVATMARK) == 0) || 539 so->so_options & SO_OOBINLINE || 540 tp->t_oobflags & TCPOOB_HADDATA) { 541 error = EINVAL; 542 break; 543 } 544 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { 545 error = EWOULDBLOCK; 546 break; 547 } 548 m->m_len = 1; 549 *mtod(m, caddr_t) = tp->t_iobc; 550 if (((long)nam & MSG_PEEK) == 0) 551 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); 552 break; 553 554 case PRU_SENDOOB: 555 if (sbspace(&so->so_snd) < -512) { 556 m_freem(m); 557 error = ENOBUFS; 558 break; 559 } 560 /* 561 * According to RFC961 (Assigned Protocols), 562 * the urgent pointer points to the last octet 563 * of urgent data. We continue, however, 564 * to consider it to indicate the first octet 565 * of data past the urgent section. 566 * Otherwise, snd_up should be one lower. 567 */ 568 sbappend(&so->so_snd, m); 569 tp->snd_up = tp->snd_una + so->so_snd.sb_cc; 570 tp->t_force = 1; 571 error = tcp_output(tp); 572 tp->t_force = 0; 573 break; 574 575 case PRU_SOCKADDR: 576 #ifdef INET 577 if (inp) 578 in_setsockaddr(inp, nam); 579 #endif 580 #ifdef INET6 581 if (in6p) 582 in6_setsockaddr(in6p, nam); 583 #endif 584 break; 585 586 case PRU_PEERADDR: 587 #ifdef INET 588 if (inp) 589 in_setpeeraddr(inp, nam); 590 #endif 591 #ifdef INET6 592 if (in6p) 593 in6_setpeeraddr(in6p, nam); 594 #endif 595 break; 596 597 default: 598 panic("tcp_usrreq"); 599 } 600 #ifdef TCP_DEBUG 601 if (tp && (so->so_options & SO_DEBUG)) 602 tcp_trace(TA_USER, ostate, tp, NULL, req); 603 #endif 604 605 release: 606 splx(s); 607 return (error); 608 } 609 610 int 611 tcp_ctloutput(op, so, level, optname, mp) 612 int op; 613 struct socket *so; 614 int level, optname; 615 struct mbuf **mp; 616 { 617 int error = 0, s; 618 struct inpcb *inp; 619 #ifdef INET6 620 struct in6pcb *in6p; 621 #endif 622 struct tcpcb *tp; 623 struct mbuf *m; 624 int i; 625 int family; /* family of the socket */ 626 627 family = so->so_proto->pr_domain->dom_family; 628 629 s = splsoftnet(); 630 switch (family) { 631 #ifdef INET 632 case PF_INET: 633 inp = sotoinpcb(so); 634 #ifdef INET6 635 in6p = NULL; 636 #endif 637 break; 638 #endif 639 #ifdef INET6 640 case PF_INET6: 641 inp = NULL; 642 in6p = sotoin6pcb(so); 643 break; 644 #endif 645 default: 646 splx(s); 647 return EAFNOSUPPORT; 648 } 649 #ifndef INET6 650 if (inp == NULL) 651 #else 652 if (inp == NULL && in6p == NULL) 653 #endif 654 { 655 splx(s); 656 if (op == PRCO_SETOPT && *mp) 657 (void) m_free(*mp); 658 return (ECONNRESET); 659 } 660 if (level != IPPROTO_TCP) { 661 switch (family) { 662 #ifdef INET 663 case PF_INET: 664 error = ip_ctloutput(op, so, level, optname, mp); 665 break; 666 #endif 667 #ifdef INET6 668 case PF_INET6: 669 error = ip6_ctloutput(op, so, level, optname, mp); 670 break; 671 #endif 672 } 673 splx(s); 674 return (error); 675 } 676 if (inp) 677 tp = intotcpcb(inp); 678 #ifdef INET6 679 else if (in6p) 680 tp = in6totcpcb(in6p); 681 #endif 682 else 683 tp = NULL; 684 685 switch (op) { 686 687 case PRCO_SETOPT: 688 m = *mp; 689 switch (optname) { 690 691 case TCP_NODELAY: 692 if (m == NULL || m->m_len < sizeof (int)) 693 error = EINVAL; 694 else if (*mtod(m, int *)) 695 tp->t_flags |= TF_NODELAY; 696 else 697 tp->t_flags &= ~TF_NODELAY; 698 break; 699 700 case TCP_MAXSEG: 701 if (m && (i = *mtod(m, int *)) > 0 && 702 i <= tp->t_peermss) 703 tp->t_peermss = i; /* limit on send size */ 704 else 705 error = EINVAL; 706 break; 707 708 default: 709 error = ENOPROTOOPT; 710 break; 711 } 712 if (m) 713 (void) m_free(m); 714 break; 715 716 case PRCO_GETOPT: 717 *mp = m = m_get(M_WAIT, MT_SOOPTS); 718 m->m_len = sizeof(int); 719 720 switch (optname) { 721 case TCP_NODELAY: 722 *mtod(m, int *) = tp->t_flags & TF_NODELAY; 723 break; 724 case TCP_MAXSEG: 725 *mtod(m, int *) = tp->t_peermss; 726 break; 727 default: 728 error = ENOPROTOOPT; 729 break; 730 } 731 break; 732 } 733 splx(s); 734 return (error); 735 } 736 737 #ifndef TCP_SENDSPACE 738 #define TCP_SENDSPACE 1024*16; 739 #endif 740 int tcp_sendspace = TCP_SENDSPACE; 741 #ifndef TCP_RECVSPACE 742 #define TCP_RECVSPACE 1024*16; 743 #endif 744 int tcp_recvspace = TCP_RECVSPACE; 745 746 /* 747 * Attach TCP protocol to socket, allocating 748 * internet protocol control block, tcp control block, 749 * bufer space, and entering LISTEN state if to accept connections. 750 */ 751 int 752 tcp_attach(so) 753 struct socket *so; 754 { 755 struct tcpcb *tp; 756 struct inpcb *inp; 757 #ifdef INET6 758 struct in6pcb *in6p; 759 #endif 760 int error; 761 int family; /* family of the socket */ 762 763 family = so->so_proto->pr_domain->dom_family; 764 765 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 766 error = soreserve(so, tcp_sendspace, tcp_recvspace); 767 if (error) 768 return (error); 769 } 770 switch (family) { 771 #ifdef INET 772 case PF_INET: 773 error = in_pcballoc(so, &tcbtable); 774 if (error) 775 return (error); 776 inp = sotoinpcb(so); 777 #ifdef INET6 778 in6p = NULL; 779 #endif 780 break; 781 #endif 782 #ifdef INET6 783 case PF_INET6: 784 error = in6_pcballoc(so, &tcb6); 785 if (error) 786 return (error); 787 inp = NULL; 788 in6p = sotoin6pcb(so); 789 break; 790 #endif 791 default: 792 return EAFNOSUPPORT; 793 } 794 if (inp) 795 tp = tcp_newtcpcb(family, (void *)inp); 796 #ifdef INET6 797 else if (in6p) 798 tp = tcp_newtcpcb(family, (void *)in6p); 799 #endif 800 else 801 tp = NULL; 802 803 if (tp == 0) { 804 int nofd = so->so_state & SS_NOFDREF; /* XXX */ 805 806 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */ 807 #ifdef INET 808 if (inp) 809 in_pcbdetach(inp); 810 #endif 811 #ifdef INET6 812 if (in6p) 813 in6_pcbdetach(in6p); 814 #endif 815 so->so_state |= nofd; 816 return (ENOBUFS); 817 } 818 tp->t_state = TCPS_CLOSED; 819 return (0); 820 } 821 822 /* 823 * Initiate (or continue) disconnect. 824 * If embryonic state, just send reset (once). 825 * If in ``let data drain'' option and linger null, just drop. 826 * Otherwise (hard), mark socket disconnecting and drop 827 * current input data; switch states based on user close, and 828 * send segment to peer (with FIN). 829 */ 830 struct tcpcb * 831 tcp_disconnect(tp) 832 struct tcpcb *tp; 833 { 834 struct socket *so; 835 836 if (tp->t_inpcb) 837 so = tp->t_inpcb->inp_socket; 838 #ifdef INET6 839 else if (tp->t_in6pcb) 840 so = tp->t_in6pcb->in6p_socket; 841 #endif 842 else 843 so = NULL; 844 845 if (TCPS_HAVEESTABLISHED(tp->t_state) == 0) 846 tp = tcp_close(tp); 847 else if ((so->so_options & SO_LINGER) && so->so_linger == 0) 848 tp = tcp_drop(tp, 0); 849 else { 850 soisdisconnecting(so); 851 sbflush(&so->so_rcv); 852 tp = tcp_usrclosed(tp); 853 if (tp) 854 (void) tcp_output(tp); 855 } 856 return (tp); 857 } 858 859 /* 860 * User issued close, and wish to trail through shutdown states: 861 * if never received SYN, just forget it. If got a SYN from peer, 862 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. 863 * If already got a FIN from peer, then almost done; go to LAST_ACK 864 * state. In all other cases, have already sent FIN to peer (e.g. 865 * after PRU_SHUTDOWN), and just have to play tedious game waiting 866 * for peer to send FIN or not respond to keep-alives, etc. 867 * We can let the user exit from the close as soon as the FIN is acked. 868 */ 869 struct tcpcb * 870 tcp_usrclosed(tp) 871 struct tcpcb *tp; 872 { 873 874 switch (tp->t_state) { 875 876 case TCPS_CLOSED: 877 case TCPS_LISTEN: 878 case TCPS_SYN_SENT: 879 tp->t_state = TCPS_CLOSED; 880 tp = tcp_close(tp); 881 break; 882 883 case TCPS_SYN_RECEIVED: 884 case TCPS_ESTABLISHED: 885 tp->t_state = TCPS_FIN_WAIT_1; 886 break; 887 888 case TCPS_CLOSE_WAIT: 889 tp->t_state = TCPS_LAST_ACK; 890 break; 891 } 892 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) { 893 struct socket *so; 894 if (tp->t_inpcb) 895 so = tp->t_inpcb->inp_socket; 896 #ifdef INET6 897 else if (tp->t_in6pcb) 898 so = tp->t_in6pcb->in6p_socket; 899 #endif 900 else 901 so = NULL; 902 soisdisconnected(so); 903 /* 904 * If we are in FIN_WAIT_2, we arrived here because the 905 * application did a shutdown of the send side. Like the 906 * case of a transition from FIN_WAIT_1 to FIN_WAIT_2 after 907 * a full close, we start a timer to make sure sockets are 908 * not left in FIN_WAIT_2 forever. 909 */ 910 if ((tp->t_state == TCPS_FIN_WAIT_2) && (tcp_maxidle > 0)) 911 TCP_TIMER_ARM(tp, TCPT_2MSL, tcp_maxidle); 912 } 913 return (tp); 914 } 915 916 static const struct { 917 unsigned int valid : 1; 918 unsigned int rdonly : 1; 919 int *var; 920 int val; 921 } tcp_ctlvars[] = TCPCTL_VARIABLES; 922 923 /* 924 * Sysctl for tcp variables. 925 */ 926 int 927 tcp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 928 int *name; 929 u_int namelen; 930 void *oldp; 931 size_t *oldlenp; 932 void *newp; 933 size_t newlen; 934 { 935 936 /* All sysctl names at this level are terminal. */ 937 if (namelen != 1) 938 return (ENOTDIR); 939 940 if (name[0] < sizeof(tcp_ctlvars)/sizeof(tcp_ctlvars[0]) 941 && tcp_ctlvars[name[0]].valid) { 942 if (tcp_ctlvars[name[0]].rdonly) 943 return (sysctl_rdint(oldp, oldlenp, newp, 944 tcp_ctlvars[name[0]].val)); 945 else 946 return (sysctl_int(oldp, oldlenp, newp, newlen, 947 tcp_ctlvars[name[0]].var)); 948 } 949 950 return (ENOPROTOOPT); 951 } 952
Indexes created Sun Sep 21 20:09:37 GMT 2025