1 /* 2 * Copyright (c) 2003, 2004 Jeffrey M. Hsu. All rights reserved. 3 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved. 4 * 5 * This code is derived from software contributed to The DragonFly Project 6 * by Jeffrey M. Hsu. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of The DragonFly Project nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific, prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 30 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94 67 * $FreeBSD: src/sys/netinet/tcp_usrreq.c,v 1.51.2.17 2002/10/11 11:46:44 ume Exp $ 68 * $DragonFly: src/sys/netinet/tcp_usrreq.c,v 1.51 2008/09/29 20:52:23 dillon Exp $ 69 */ 70 71 #include "opt_ipsec.h" 72 #include "opt_inet6.h" 73 #include "opt_tcpdebug.h" 74 75 #include <sys/param.h> 76 #include <sys/systm.h> 77 #include <sys/kernel.h> 78 #include <sys/malloc.h> 79 #include <sys/sysctl.h> 80 #include <sys/globaldata.h> 81 #include <sys/thread.h> 82 83 #include <sys/mbuf.h> 84 #ifdef INET6 85 #include <sys/domain.h> 86 #endif /* INET6 */ 87 #include <sys/socket.h> 88 #include <sys/socketvar.h> 89 #include <sys/protosw.h> 90 91 #include <sys/thread2.h> 92 #include <sys/msgport2.h> 93 94 #include <net/if.h> 95 #include <net/netisr.h> 96 #include <net/route.h> 97 98 #include <net/netmsg2.h> 99 100 #include <netinet/in.h> 101 #include <netinet/in_systm.h> 102 #ifdef INET6 103 #include <netinet/ip6.h> 104 #endif 105 #include <netinet/in_pcb.h> 106 #ifdef INET6 107 #include <netinet6/in6_pcb.h> 108 #endif 109 #include <netinet/in_var.h> 110 #include <netinet/ip_var.h> 111 #ifdef INET6 112 #include <netinet6/ip6_var.h> 113 #include <netinet6/tcp6_var.h> 114 #endif 115 #include <netinet/tcp.h> 116 #include <netinet/tcp_fsm.h> 117 #include <netinet/tcp_seq.h> 118 #include <netinet/tcp_timer.h> 119 #include <netinet/tcp_timer2.h> 120 #include <netinet/tcp_var.h> 121 #include <netinet/tcpip.h> 122 #ifdef TCPDEBUG 123 #include <netinet/tcp_debug.h> 124 #endif 125 126 #ifdef IPSEC 127 #include <netinet6/ipsec.h> 128 #endif /*IPSEC*/ 129 130 /* 131 * TCP protocol interface to socket abstraction. 132 */ 133 extern char *tcpstates[]; /* XXX ??? */ 134 135 static int tcp_attach (struct socket *, struct pru_attach_info *); 136 static int tcp_connect (struct tcpcb *, int flags, struct mbuf *m, 137 struct sockaddr *, struct thread *); 138 #ifdef INET6 139 static int tcp6_connect (struct tcpcb *, int flags, struct mbuf *m, 140 struct sockaddr *, struct thread *); 141 static int tcp6_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf *m, 142 struct sockaddr_in6 *sin6, 143 struct in6_addr *addr6); 144 #endif /* INET6 */ 145 static struct tcpcb * 146 tcp_disconnect (struct tcpcb *); 147 static struct tcpcb * 148 tcp_usrclosed (struct tcpcb *); 149 150 #ifdef TCPDEBUG 151 #define TCPDEBUG0 int ostate = 0 152 #define TCPDEBUG1() ostate = tp ? tp->t_state : 0 153 #define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \ 154 tcp_trace(TA_USER, ostate, tp, 0, 0, req) 155 #else 156 #define TCPDEBUG0 157 #define TCPDEBUG1() 158 #define TCPDEBUG2(req) 159 #endif 160 161 /* 162 * TCP attaches to socket via pru_attach(), reserving space, 163 * and an internet control block. 164 */ 165 static int 166 tcp_usr_attach(struct socket *so, int proto, struct pru_attach_info *ai) 167 { 168 int error; 169 struct inpcb *inp; 170 struct tcpcb *tp = 0; 171 TCPDEBUG0; 172 173 crit_enter(); 174 inp = so->so_pcb; 175 TCPDEBUG1(); 176 if (inp) { 177 error = EISCONN; 178 goto out; 179 } 180 181 error = tcp_attach(so, ai); 182 if (error) 183 goto out; 184 185 if ((so->so_options & SO_LINGER) && so->so_linger == 0) 186 so->so_linger = TCP_LINGERTIME; 187 tp = sototcpcb(so); 188 out: 189 TCPDEBUG2(PRU_ATTACH); 190 crit_exit(); 191 return error; 192 } 193 194 /* 195 * pru_detach() detaches the TCP protocol from the socket. 196 * If the protocol state is non-embryonic, then can't 197 * do this directly: have to initiate a pru_disconnect(), 198 * which may finish later; embryonic TCB's can just 199 * be discarded here. 200 */ 201 static int 202 tcp_usr_detach(struct socket *so) 203 { 204 int error = 0; 205 struct inpcb *inp; 206 struct tcpcb *tp; 207 TCPDEBUG0; 208 209 crit_enter(); 210 inp = so->so_pcb; 211 212 /* 213 * If the inp is already detached it may have been due to an async 214 * close. Just return as if no error occured. 215 */ 216 if (inp == NULL) { 217 crit_exit(); 218 return 0; 219 } 220 221 /* 222 * It's possible for the tcpcb (tp) to disconnect from the inp due 223 * to tcp_drop()->tcp_close() being called. This may occur *after* 224 * the detach message has been queued so we may find a NULL tp here. 225 */ 226 if ((tp = intotcpcb(inp)) != NULL) { 227 TCPDEBUG1(); 228 tp = tcp_disconnect(tp); 229 TCPDEBUG2(PRU_DETACH); 230 } 231 crit_exit(); 232 return error; 233 } 234 235 /* 236 * Note: ignore_error is non-zero for certain disconnection races 237 * which we want to silently allow, otherwise close() may return 238 * an unexpected error. 239 */ 240 #define COMMON_START(so, inp, ignore_error) \ 241 TCPDEBUG0; \ 242 \ 243 crit_enter(); \ 244 inp = so->so_pcb; \ 245 do { \ 246 if (inp == NULL) { \ 247 crit_exit(); \ 248 return (ignore_error ? 0 : EINVAL); \ 249 } \ 250 tp = intotcpcb(inp); \ 251 TCPDEBUG1(); \ 252 } while(0) 253 254 #define COMMON_END(req) out: TCPDEBUG2(req); crit_exit(); return error; goto out 255 256 257 /* 258 * Give the socket an address. 259 */ 260 static int 261 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 262 { 263 int error = 0; 264 struct inpcb *inp; 265 struct tcpcb *tp; 266 struct sockaddr_in *sinp; 267 268 COMMON_START(so, inp, 0); 269 270 /* 271 * Must check for multicast addresses and disallow binding 272 * to them. 273 */ 274 sinp = (struct sockaddr_in *)nam; 275 if (sinp->sin_family == AF_INET && 276 IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { 277 error = EAFNOSUPPORT; 278 goto out; 279 } 280 error = in_pcbbind(inp, nam, td); 281 if (error) 282 goto out; 283 COMMON_END(PRU_BIND); 284 285 } 286 287 #ifdef INET6 288 static int 289 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 290 { 291 int error = 0; 292 struct inpcb *inp; 293 struct tcpcb *tp; 294 struct sockaddr_in6 *sin6p; 295 296 COMMON_START(so, inp, 0); 297 298 /* 299 * Must check for multicast addresses and disallow binding 300 * to them. 301 */ 302 sin6p = (struct sockaddr_in6 *)nam; 303 if (sin6p->sin6_family == AF_INET6 && 304 IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) { 305 error = EAFNOSUPPORT; 306 goto out; 307 } 308 inp->inp_vflag &= ~INP_IPV4; 309 inp->inp_vflag |= INP_IPV6; 310 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) { 311 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr)) 312 inp->inp_vflag |= INP_IPV4; 313 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { 314 struct sockaddr_in sin; 315 316 in6_sin6_2_sin(&sin, sin6p); 317 inp->inp_vflag |= INP_IPV4; 318 inp->inp_vflag &= ~INP_IPV6; 319 error = in_pcbbind(inp, (struct sockaddr *)&sin, td); 320 goto out; 321 } 322 } 323 error = in6_pcbbind(inp, nam, td); 324 if (error) 325 goto out; 326 COMMON_END(PRU_BIND); 327 } 328 #endif /* INET6 */ 329 330 #ifdef SMP 331 struct netmsg_inswildcard { 332 struct netmsg nm_netmsg; 333 struct inpcb *nm_inp; 334 struct inpcbinfo *nm_pcbinfo; 335 }; 336 337 static void 338 in_pcbinswildcardhash_handler(struct netmsg *msg0) 339 { 340 struct netmsg_inswildcard *msg = (struct netmsg_inswildcard *)msg0; 341 342 in_pcbinswildcardhash_oncpu(msg->nm_inp, msg->nm_pcbinfo); 343 lwkt_replymsg(&msg->nm_netmsg.nm_lmsg, 0); 344 } 345 #endif 346 347 /* 348 * Prepare to accept connections. 349 */ 350 static int 351 tcp_usr_listen(struct socket *so, struct thread *td) 352 { 353 int error = 0; 354 struct inpcb *inp; 355 struct tcpcb *tp; 356 #ifdef SMP 357 int cpu; 358 #endif 359 360 COMMON_START(so, inp, 0); 361 if (inp->inp_lport == 0) { 362 error = in_pcbbind(inp, NULL, td); 363 if (error != 0) 364 goto out; 365 } 366 367 tp->t_state = TCPS_LISTEN; 368 tp->tt_msg = NULL; /* Catch any invalid timer usage */ 369 #ifdef SMP 370 /* 371 * We have to set the flag because we can't have other cpus 372 * messing with our inp's flags. 373 */ 374 inp->inp_flags |= INP_WILDCARD_MP; 375 for (cpu = 0; cpu < ncpus2; cpu++) { 376 struct netmsg_inswildcard *msg; 377 378 if (cpu == mycpu->gd_cpuid) { 379 in_pcbinswildcardhash(inp); 380 continue; 381 } 382 383 msg = kmalloc(sizeof(struct netmsg_inswildcard), M_LWKTMSG, 384 M_INTWAIT); 385 netmsg_init(&msg->nm_netmsg, NULL, &netisr_afree_rport, 386 0, in_pcbinswildcardhash_handler); 387 msg->nm_inp = inp; 388 msg->nm_pcbinfo = &tcbinfo[cpu]; 389 lwkt_sendmsg(tcp_cport(cpu), &msg->nm_netmsg.nm_lmsg); 390 } 391 #else 392 in_pcbinswildcardhash(inp); 393 #endif 394 COMMON_END(PRU_LISTEN); 395 } 396 397 #ifdef INET6 398 static int 399 tcp6_usr_listen(struct socket *so, struct thread *td) 400 { 401 int error = 0; 402 struct inpcb *inp; 403 struct tcpcb *tp; 404 #ifdef SMP 405 int cpu; 406 #endif 407 408 COMMON_START(so, inp, 0); 409 if (inp->inp_lport == 0) { 410 if (!(inp->inp_flags & IN6P_IPV6_V6ONLY)) 411 inp->inp_vflag |= INP_IPV4; 412 else 413 inp->inp_vflag &= ~INP_IPV4; 414 error = in6_pcbbind(inp, NULL, td); 415 } 416 if (error == 0) 417 tp->t_state = TCPS_LISTEN; 418 #ifdef SMP 419 /* 420 * We have to set the flag because we can't have other cpus 421 * messing with our inp's flags. 422 */ 423 inp->inp_flags |= INP_WILDCARD_MP; 424 for (cpu = 0; cpu < ncpus2; cpu++) { 425 struct netmsg_inswildcard *msg; 426 427 if (cpu == mycpu->gd_cpuid) { 428 in_pcbinswildcardhash(inp); 429 continue; 430 } 431 432 msg = kmalloc(sizeof(struct netmsg_inswildcard), M_LWKTMSG, 433 M_INTWAIT); 434 netmsg_init(&msg->nm_netmsg, NULL, &netisr_afree_rport, 435 0, in_pcbinswildcardhash_handler); 436 msg->nm_inp = inp; 437 msg->nm_pcbinfo = &tcbinfo[cpu]; 438 lwkt_sendmsg(tcp_cport(cpu), &msg->nm_netmsg.nm_lmsg); 439 } 440 #else 441 in_pcbinswildcardhash(inp); 442 #endif 443 COMMON_END(PRU_LISTEN); 444 } 445 #endif /* INET6 */ 446 447 /* 448 * Initiate connection to peer. 449 * Create a template for use in transmissions on this connection. 450 * Enter SYN_SENT state, and mark socket as connecting. 451 * Start keep-alive timer, and seed output sequence space. 452 * Send initial segment on connection. 453 */ 454 static int 455 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 456 { 457 int error = 0; 458 struct inpcb *inp; 459 struct tcpcb *tp; 460 struct sockaddr_in *sinp; 461 462 COMMON_START(so, inp, 0); 463 464 /* 465 * Must disallow TCP ``connections'' to multicast addresses. 466 */ 467 sinp = (struct sockaddr_in *)nam; 468 if (sinp->sin_family == AF_INET 469 && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { 470 error = EAFNOSUPPORT; 471 goto out; 472 } 473 474 if (!prison_remote_ip(td, (struct sockaddr*)sinp)) { 475 error = EAFNOSUPPORT; /* IPv6 only jail */ 476 goto out; 477 } 478 479 if ((error = tcp_connect(tp, 0, NULL, nam, td)) != 0) 480 goto out; 481 COMMON_END(PRU_CONNECT); 482 } 483 484 #ifdef INET6 485 static int 486 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 487 { 488 int error = 0; 489 struct inpcb *inp; 490 struct tcpcb *tp; 491 struct sockaddr_in6 *sin6p; 492 493 COMMON_START(so, inp, 0); 494 495 /* 496 * Must disallow TCP ``connections'' to multicast addresses. 497 */ 498 sin6p = (struct sockaddr_in6 *)nam; 499 if (sin6p->sin6_family == AF_INET6 500 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) { 501 error = EAFNOSUPPORT; 502 goto out; 503 } 504 505 if (!prison_remote_ip(td, nam)) { 506 error = EAFNOSUPPORT; /* IPv4 only jail */ 507 goto out; 508 } 509 510 if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { 511 struct sockaddr_in sin; 512 513 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) { 514 error = EINVAL; 515 goto out; 516 } 517 518 in6_sin6_2_sin(&sin, sin6p); 519 inp->inp_vflag |= INP_IPV4; 520 inp->inp_vflag &= ~INP_IPV6; 521 error = tcp_connect(tp, 0, NULL, (struct sockaddr *)&sin, td); 522 if (error) 523 goto out; 524 goto out; 525 } 526 inp->inp_vflag &= ~INP_IPV4; 527 inp->inp_vflag |= INP_IPV6; 528 inp->inp_inc.inc_isipv6 = 1; 529 if ((error = tcp6_connect(tp, 0, NULL, nam, td)) != 0) 530 goto out; 531 error = tcp_output(tp); 532 COMMON_END(PRU_CONNECT); 533 } 534 #endif /* INET6 */ 535 536 /* 537 * Initiate disconnect from peer. 538 * If connection never passed embryonic stage, just drop; 539 * else if don't need to let data drain, then can just drop anyways, 540 * else have to begin TCP shutdown process: mark socket disconnecting, 541 * drain unread data, state switch to reflect user close, and 542 * send segment (e.g. FIN) to peer. Socket will be really disconnected 543 * when peer sends FIN and acks ours. 544 * 545 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB. 546 */ 547 static int 548 tcp_usr_disconnect(struct socket *so) 549 { 550 int error = 0; 551 struct inpcb *inp; 552 struct tcpcb *tp; 553 554 COMMON_START(so, inp, 1); 555 tp = tcp_disconnect(tp); 556 COMMON_END(PRU_DISCONNECT); 557 } 558 559 /* 560 * Accept a connection. Essentially all the work is 561 * done at higher levels; just return the address 562 * of the peer, storing through addr. 563 */ 564 static int 565 tcp_usr_accept(struct socket *so, struct sockaddr **nam) 566 { 567 int error = 0; 568 struct inpcb *inp; 569 struct tcpcb *tp = NULL; 570 TCPDEBUG0; 571 572 crit_enter(); 573 inp = so->so_pcb; 574 if (so->so_state & SS_ISDISCONNECTED) { 575 error = ECONNABORTED; 576 goto out; 577 } 578 if (inp == 0) { 579 crit_exit(); 580 return (EINVAL); 581 } 582 tp = intotcpcb(inp); 583 TCPDEBUG1(); 584 in_setpeeraddr(so, nam); 585 COMMON_END(PRU_ACCEPT); 586 } 587 588 #ifdef INET6 589 static int 590 tcp6_usr_accept(struct socket *so, struct sockaddr **nam) 591 { 592 int error = 0; 593 struct inpcb *inp; 594 struct tcpcb *tp = NULL; 595 TCPDEBUG0; 596 597 crit_enter(); 598 inp = so->so_pcb; 599 600 if (so->so_state & SS_ISDISCONNECTED) { 601 error = ECONNABORTED; 602 goto out; 603 } 604 if (inp == 0) { 605 crit_exit(); 606 return (EINVAL); 607 } 608 tp = intotcpcb(inp); 609 TCPDEBUG1(); 610 in6_mapped_peeraddr(so, nam); 611 COMMON_END(PRU_ACCEPT); 612 } 613 #endif /* INET6 */ 614 /* 615 * Mark the connection as being incapable of further output. 616 */ 617 static int 618 tcp_usr_shutdown(struct socket *so) 619 { 620 int error = 0; 621 struct inpcb *inp; 622 struct tcpcb *tp; 623 624 COMMON_START(so, inp, 0); 625 socantsendmore(so); 626 tp = tcp_usrclosed(tp); 627 if (tp) 628 error = tcp_output(tp); 629 COMMON_END(PRU_SHUTDOWN); 630 } 631 632 /* 633 * After a receive, possibly send window update to peer. 634 */ 635 static int 636 tcp_usr_rcvd(struct socket *so, int flags) 637 { 638 int error = 0; 639 struct inpcb *inp; 640 struct tcpcb *tp; 641 642 COMMON_START(so, inp, 0); 643 tcp_output(tp); 644 COMMON_END(PRU_RCVD); 645 } 646 647 /* 648 * Do a send by putting data in output queue and updating urgent 649 * marker if URG set. Possibly send more data. Unlike the other 650 * pru_*() routines, the mbuf chains are our responsibility. We 651 * must either enqueue them or free them. The other pru_* routines 652 * generally are caller-frees. 653 */ 654 static int 655 tcp_usr_send(struct socket *so, int flags, struct mbuf *m, 656 struct sockaddr *nam, struct mbuf *control, struct thread *td) 657 { 658 int error = 0; 659 struct inpcb *inp; 660 struct tcpcb *tp; 661 #ifdef INET6 662 int isipv6; 663 #endif 664 TCPDEBUG0; 665 666 crit_enter(); 667 inp = so->so_pcb; 668 669 if (inp == NULL) { 670 /* 671 * OOPS! we lost a race, the TCP session got reset after 672 * we checked SS_CANTSENDMORE, eg: while doing uiomove or a 673 * network interrupt in the non-critical section of sosend(). 674 */ 675 m_freem(m); 676 if (control) 677 m_freem(control); 678 error = ECONNRESET; /* XXX EPIPE? */ 679 tp = NULL; 680 TCPDEBUG1(); 681 goto out; 682 } 683 #ifdef INET6 684 isipv6 = nam && nam->sa_family == AF_INET6; 685 #endif /* INET6 */ 686 tp = intotcpcb(inp); 687 TCPDEBUG1(); 688 if (control) { 689 /* TCP doesn't do control messages (rights, creds, etc) */ 690 if (control->m_len) { 691 m_freem(control); 692 m_freem(m); 693 error = EINVAL; 694 goto out; 695 } 696 m_freem(control); /* empty control, just free it */ 697 } 698 699 /* 700 * Don't let too much OOB data build up 701 */ 702 if (flags & PRUS_OOB) { 703 if (ssb_space(&so->so_snd) < -512) { 704 m_freem(m); 705 error = ENOBUFS; 706 goto out; 707 } 708 } 709 710 /* 711 * Do implied connect if not yet connected. Any data sent 712 * with the connect is handled by tcp_connect() and friends. 713 * 714 * NOTE! PROTOCOL THREAD MAY BE CHANGED BY THE CONNECT! 715 */ 716 if (nam && tp->t_state < TCPS_SYN_SENT) { 717 #ifdef INET6 718 if (isipv6) 719 error = tcp6_connect(tp, flags, m, nam, td); 720 else 721 #endif /* INET6 */ 722 error = tcp_connect(tp, flags, m, nam, td); 723 #if 0 724 /* WTF is this doing here? */ 725 tp->snd_wnd = TTCP_CLIENT_SND_WND; 726 tcp_mss(tp, -1); 727 #endif 728 goto out; 729 } 730 731 /* 732 * Pump the data into the socket. 733 */ 734 if (m) 735 ssb_appendstream(&so->so_snd, m); 736 if (flags & PRUS_OOB) { 737 /* 738 * According to RFC961 (Assigned Protocols), 739 * the urgent pointer points to the last octet 740 * of urgent data. We continue, however, 741 * to consider it to indicate the first octet 742 * of data past the urgent section. 743 * Otherwise, snd_up should be one lower. 744 */ 745 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc; 746 tp->t_flags |= TF_FORCE; 747 error = tcp_output(tp); 748 tp->t_flags &= ~TF_FORCE; 749 } else { 750 if (flags & PRUS_EOF) { 751 /* 752 * Close the send side of the connection after 753 * the data is sent. 754 */ 755 socantsendmore(so); 756 tp = tcp_usrclosed(tp); 757 } 758 if (tp != NULL) { 759 if (flags & PRUS_MORETOCOME) 760 tp->t_flags |= TF_MORETOCOME; 761 error = tcp_output(tp); 762 if (flags & PRUS_MORETOCOME) 763 tp->t_flags &= ~TF_MORETOCOME; 764 } 765 } 766 COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB : 767 ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND)); 768 } 769 770 /* 771 * Abort the TCP. 772 */ 773 static int 774 tcp_usr_abort(struct socket *so) 775 { 776 int error = 0; 777 struct inpcb *inp; 778 struct tcpcb *tp; 779 780 COMMON_START(so, inp, 1); 781 tp = tcp_drop(tp, ECONNABORTED); 782 COMMON_END(PRU_ABORT); 783 } 784 785 /* 786 * Receive out-of-band data. 787 */ 788 static int 789 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags) 790 { 791 int error = 0; 792 struct inpcb *inp; 793 struct tcpcb *tp; 794 795 COMMON_START(so, inp, 0); 796 if ((so->so_oobmark == 0 && 797 (so->so_state & SS_RCVATMARK) == 0) || 798 so->so_options & SO_OOBINLINE || 799 tp->t_oobflags & TCPOOB_HADDATA) { 800 error = EINVAL; 801 goto out; 802 } 803 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { 804 error = EWOULDBLOCK; 805 goto out; 806 } 807 m->m_len = 1; 808 *mtod(m, caddr_t) = tp->t_iobc; 809 if ((flags & MSG_PEEK) == 0) 810 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); 811 COMMON_END(PRU_RCVOOB); 812 } 813 814 /* xxx - should be const */ 815 struct pr_usrreqs tcp_usrreqs = { 816 .pru_abort = tcp_usr_abort, 817 .pru_accept = tcp_usr_accept, 818 .pru_attach = tcp_usr_attach, 819 .pru_bind = tcp_usr_bind, 820 .pru_connect = tcp_usr_connect, 821 .pru_connect2 = pru_connect2_notsupp, 822 .pru_control = in_control, 823 .pru_detach = tcp_usr_detach, 824 .pru_disconnect = tcp_usr_disconnect, 825 .pru_listen = tcp_usr_listen, 826 .pru_peeraddr = in_setpeeraddr, 827 .pru_rcvd = tcp_usr_rcvd, 828 .pru_rcvoob = tcp_usr_rcvoob, 829 .pru_send = tcp_usr_send, 830 .pru_sense = pru_sense_null, 831 .pru_shutdown = tcp_usr_shutdown, 832 .pru_sockaddr = in_setsockaddr, 833 .pru_sosend = sosend, 834 .pru_soreceive = soreceive, 835 .pru_sopoll = sopoll 836 }; 837 838 #ifdef INET6 839 struct pr_usrreqs tcp6_usrreqs = { 840 .pru_abort = tcp_usr_abort, 841 .pru_accept = tcp6_usr_accept, 842 .pru_attach = tcp_usr_attach, 843 .pru_bind = tcp6_usr_bind, 844 .pru_connect = tcp6_usr_connect, 845 .pru_connect2 = pru_connect2_notsupp, 846 .pru_control = in6_control, 847 .pru_detach = tcp_usr_detach, 848 .pru_disconnect = tcp_usr_disconnect, 849 .pru_listen = tcp6_usr_listen, 850 .pru_peeraddr = in6_mapped_peeraddr, 851 .pru_rcvd = tcp_usr_rcvd, 852 .pru_rcvoob = tcp_usr_rcvoob, 853 .pru_send = tcp_usr_send, 854 .pru_sense = pru_sense_null, 855 .pru_shutdown = tcp_usr_shutdown, 856 .pru_sockaddr = in6_mapped_sockaddr, 857 .pru_sosend = sosend, 858 .pru_soreceive = soreceive, 859 .pru_sopoll = sopoll 860 }; 861 #endif /* INET6 */ 862 863 static int 864 tcp_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf *m, 865 struct sockaddr_in *sin, struct sockaddr_in *if_sin) 866 { 867 struct inpcb *inp = tp->t_inpcb, *oinp; 868 struct socket *so = inp->inp_socket; 869 struct route *ro = &inp->inp_route; 870 871 oinp = in_pcblookup_hash(&tcbinfo[mycpu->gd_cpuid], 872 sin->sin_addr, sin->sin_port, 873 inp->inp_laddr.s_addr != INADDR_ANY ? 874 inp->inp_laddr : if_sin->sin_addr, 875 inp->inp_lport, 0, NULL); 876 if (oinp != NULL) { 877 m_freem(m); 878 return (EADDRINUSE); 879 } 880 if (inp->inp_laddr.s_addr == INADDR_ANY) 881 inp->inp_laddr = if_sin->sin_addr; 882 inp->inp_faddr = sin->sin_addr; 883 inp->inp_fport = sin->sin_port; 884 inp->inp_cpcbinfo = &tcbinfo[mycpu->gd_cpuid]; 885 in_pcbinsconnhash(inp); 886 887 /* 888 * We are now on the inpcb's owner CPU, if the cached route was 889 * freed because the rtentry's owner CPU is not the current CPU 890 * (e.g. in tcp_connect()), then we try to reallocate it here with 891 * the hope that a rtentry may be cloned from a RTF_PRCLONING 892 * rtentry. 893 */ 894 if (!(inp->inp_socket->so_options & SO_DONTROUTE) && /*XXX*/ 895 ro->ro_rt == NULL) { 896 bzero(&ro->ro_dst, sizeof(struct sockaddr_in)); 897 ro->ro_dst.sa_family = AF_INET; 898 ro->ro_dst.sa_len = sizeof(struct sockaddr_in); 899 ((struct sockaddr_in *)&ro->ro_dst)->sin_addr = 900 sin->sin_addr; 901 rtalloc(ro); 902 } 903 904 /* 905 * Now that no more errors can occur, change the protocol processing 906 * port to the current thread (which is the correct thread). 907 * 908 * Create TCP timer message now; we are on the tcpcb's owner 909 * CPU/thread. 910 */ 911 sosetport(so, &curthread->td_msgport); 912 tcp_create_timermsg(tp, &curthread->td_msgport); 913 914 /* 915 * Compute window scaling to request. Use a larger scaling then 916 * needed for the initial receive buffer in case the receive buffer 917 * gets expanded. 918 */ 919 if (tp->request_r_scale < TCP_MIN_WINSHIFT) 920 tp->request_r_scale = TCP_MIN_WINSHIFT; 921 while (tp->request_r_scale < TCP_MAX_WINSHIFT && 922 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.ssb_hiwat 923 ) { 924 tp->request_r_scale++; 925 } 926 927 soisconnecting(so); 928 tcpstat.tcps_connattempt++; 929 tp->t_state = TCPS_SYN_SENT; 930 tcp_callout_reset(tp, tp->tt_keep, tcp_keepinit, tcp_timer_keep); 931 tp->iss = tcp_new_isn(tp); 932 tcp_sendseqinit(tp); 933 if (m) { 934 ssb_appendstream(&so->so_snd, m); 935 m = NULL; 936 if (flags & PRUS_OOB) 937 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc; 938 } 939 940 /* 941 * Close the send side of the connection after 942 * the data is sent if flagged. 943 */ 944 if ((flags & (PRUS_OOB|PRUS_EOF)) == PRUS_EOF) { 945 socantsendmore(so); 946 tp = tcp_usrclosed(tp); 947 } 948 return (tcp_output(tp)); 949 } 950 951 #ifdef SMP 952 953 struct netmsg_tcp_connect { 954 struct netmsg nm_netmsg; 955 struct tcpcb *nm_tp; 956 struct sockaddr_in *nm_sin; 957 struct sockaddr_in *nm_ifsin; 958 int nm_flags; 959 struct mbuf *nm_m; 960 }; 961 962 static void 963 tcp_connect_handler(netmsg_t netmsg) 964 { 965 struct netmsg_tcp_connect *msg = (void *)netmsg; 966 int error; 967 968 error = tcp_connect_oncpu(msg->nm_tp, msg->nm_flags, msg->nm_m, 969 msg->nm_sin, msg->nm_ifsin); 970 lwkt_replymsg(&msg->nm_netmsg.nm_lmsg, error); 971 } 972 973 struct netmsg_tcp6_connect { 974 struct netmsg nm_netmsg; 975 struct tcpcb *nm_tp; 976 struct sockaddr_in6 *nm_sin6; 977 struct in6_addr *nm_addr6; 978 int nm_flags; 979 struct mbuf *nm_m; 980 }; 981 982 static void 983 tcp6_connect_handler(netmsg_t netmsg) 984 { 985 struct netmsg_tcp6_connect *msg = (void *)netmsg; 986 int error; 987 988 error = tcp6_connect_oncpu(msg->nm_tp, msg->nm_flags, msg->nm_m, 989 msg->nm_sin6, msg->nm_addr6); 990 lwkt_replymsg(&msg->nm_netmsg.nm_lmsg, error); 991 } 992 993 #endif 994 995 /* 996 * Common subroutine to open a TCP connection to remote host specified 997 * by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local 998 * port number if needed. Call in_pcbladdr to do the routing and to choose 999 * a local host address (interface). 1000 * Initialize connection parameters and enter SYN-SENT state. 1001 */ 1002 static int 1003 tcp_connect(struct tcpcb *tp, int flags, struct mbuf *m, 1004 struct sockaddr *nam, struct thread *td) 1005 { 1006 struct inpcb *inp = tp->t_inpcb; 1007 struct sockaddr_in *sin = (struct sockaddr_in *)nam; 1008 struct sockaddr_in *if_sin; 1009 int error; 1010 #ifdef SMP 1011 lwkt_port_t port; 1012 #endif 1013 1014 /* 1015 * Bind if we have to 1016 */ 1017 if (inp->inp_lport == 0) { 1018 error = in_pcbbind(inp, NULL, td); 1019 if (error) { 1020 m_freem(m); 1021 return (error); 1022 } 1023 } 1024 1025 /* 1026 * Calculate the correct protocol processing thread. The connect 1027 * operation must run there. 1028 */ 1029 error = in_pcbladdr(inp, nam, &if_sin, td); 1030 if (error) { 1031 m_freem(m); 1032 return (error); 1033 } 1034 1035 #ifdef SMP 1036 port = tcp_addrport(sin->sin_addr.s_addr, sin->sin_port, 1037 inp->inp_laddr.s_addr ? 1038 inp->inp_laddr.s_addr : if_sin->sin_addr.s_addr, 1039 inp->inp_lport); 1040 1041 if (port != &curthread->td_msgport) { 1042 struct netmsg_tcp_connect msg; 1043 struct route *ro = &inp->inp_route; 1044 1045 /* 1046 * in_pcbladdr() may have allocated a route entry for us 1047 * on the current CPU, but we need a route entry on the 1048 * inpcb's owner CPU, so free it here. 1049 */ 1050 if (ro->ro_rt != NULL) 1051 RTFREE(ro->ro_rt); 1052 bzero(ro, sizeof(*ro)); 1053 1054 /* 1055 * NOTE: We haven't set so->so_port yet do not pass so 1056 * to netmsg_init() or it will be improperly forwarded. 1057 */ 1058 netmsg_init(&msg.nm_netmsg, NULL, &curthread->td_msgport, 1059 0, tcp_connect_handler); 1060 msg.nm_tp = tp; 1061 msg.nm_sin = sin; 1062 msg.nm_ifsin = if_sin; 1063 msg.nm_flags = flags; 1064 msg.nm_m = m; 1065 error = lwkt_domsg(port, &msg.nm_netmsg.nm_lmsg, 0); 1066 } else { 1067 error = tcp_connect_oncpu(tp, flags, m, sin, if_sin); 1068 } 1069 #else 1070 error = tcp_connect_oncpu(tp, flags, m, sin, if_sin); 1071 #endif 1072 return (error); 1073 } 1074 1075 #ifdef INET6 1076 1077 static int 1078 tcp6_connect(struct tcpcb *tp, int flags, struct mbuf *m, 1079 struct sockaddr *nam, struct thread *td) 1080 { 1081 struct inpcb *inp = tp->t_inpcb; 1082 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam; 1083 struct in6_addr *addr6; 1084 #ifdef SMP 1085 lwkt_port_t port; 1086 #endif 1087 int error; 1088 1089 if (inp->inp_lport == 0) { 1090 error = in6_pcbbind(inp, NULL, td); 1091 if (error) { 1092 m_freem(m); 1093 return (error); 1094 } 1095 } 1096 1097 /* 1098 * Cannot simply call in_pcbconnect, because there might be an 1099 * earlier incarnation of this same connection still in 1100 * TIME_WAIT state, creating an ADDRINUSE error. 1101 */ 1102 error = in6_pcbladdr(inp, nam, &addr6, td); 1103 if (error) { 1104 m_freem(m); 1105 return (error); 1106 } 1107 1108 #ifdef SMP 1109 port = tcp6_addrport(); /* XXX hack for now, always cpu0 */ 1110 1111 if (port != &curthread->td_msgport) { 1112 struct netmsg_tcp6_connect msg; 1113 struct route *ro = &inp->inp_route; 1114 1115 /* 1116 * in_pcbladdr() may have allocated a route entry for us 1117 * on the current CPU, but we need a route entry on the 1118 * inpcb's owner CPU, so free it here. 1119 */ 1120 if (ro->ro_rt != NULL) 1121 RTFREE(ro->ro_rt); 1122 bzero(ro, sizeof(*ro)); 1123 1124 netmsg_init(&msg.nm_netmsg, NULL, &curthread->td_msgport, 1125 0, tcp6_connect_handler); 1126 msg.nm_tp = tp; 1127 msg.nm_sin6 = sin6; 1128 msg.nm_addr6 = addr6; 1129 msg.nm_flags = flags; 1130 msg.nm_m = m; 1131 error = lwkt_domsg(port, &msg.nm_netmsg.nm_lmsg, 0); 1132 } else { 1133 error = tcp6_connect_oncpu(tp, flags, m, sin6, addr6); 1134 } 1135 #else 1136 error = tcp6_connect_oncpu(tp, flags, m, sin6, addr6); 1137 #endif 1138 return (error); 1139 } 1140 1141 static int 1142 tcp6_connect_oncpu(struct tcpcb *tp, int flags, struct mbuf *m, 1143 struct sockaddr_in6 *sin6, struct in6_addr *addr6) 1144 { 1145 struct inpcb *inp = tp->t_inpcb; 1146 struct socket *so = inp->inp_socket; 1147 struct inpcb *oinp; 1148 1149 /* 1150 * Cannot simply call in_pcbconnect, because there might be an 1151 * earlier incarnation of this same connection still in 1152 * TIME_WAIT state, creating an ADDRINUSE error. 1153 */ 1154 oinp = in6_pcblookup_hash(inp->inp_cpcbinfo, 1155 &sin6->sin6_addr, sin6->sin6_port, 1156 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) ? 1157 addr6 : &inp->in6p_laddr, 1158 inp->inp_lport, 0, NULL); 1159 if (oinp) { 1160 m_freem(m); 1161 return (EADDRINUSE); 1162 } 1163 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) 1164 inp->in6p_laddr = *addr6; 1165 inp->in6p_faddr = sin6->sin6_addr; 1166 inp->inp_fport = sin6->sin6_port; 1167 if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0) 1168 inp->in6p_flowinfo = sin6->sin6_flowinfo; 1169 in_pcbinsconnhash(inp); 1170 1171 /* 1172 * Now that no more errors can occur, change the protocol processing 1173 * port to the current thread (which is the correct thread). 1174 * 1175 * Create TCP timer message now; we are on the tcpcb's owner 1176 * CPU/thread. 1177 */ 1178 sosetport(so, &curthread->td_msgport); 1179 tcp_create_timermsg(tp, &curthread->td_msgport); 1180 1181 /* Compute window scaling to request. */ 1182 if (tp->request_r_scale < TCP_MIN_WINSHIFT) 1183 tp->request_r_scale = TCP_MIN_WINSHIFT; 1184 while (tp->request_r_scale < TCP_MAX_WINSHIFT && 1185 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.ssb_hiwat) { 1186 tp->request_r_scale++; 1187 } 1188 1189 soisconnecting(so); 1190 tcpstat.tcps_connattempt++; 1191 tp->t_state = TCPS_SYN_SENT; 1192 tcp_callout_reset(tp, tp->tt_keep, tcp_keepinit, tcp_timer_keep); 1193 tp->iss = tcp_new_isn(tp); 1194 tcp_sendseqinit(tp); 1195 if (m) { 1196 ssb_appendstream(&so->so_snd, m); 1197 m = NULL; 1198 if (flags & PRUS_OOB) 1199 tp->snd_up = tp->snd_una + so->so_snd.ssb_cc; 1200 } 1201 1202 /* 1203 * Close the send side of the connection after 1204 * the data is sent if flagged. 1205 */ 1206 if ((flags & (PRUS_OOB|PRUS_EOF)) == PRUS_EOF) { 1207 socantsendmore(so); 1208 tp = tcp_usrclosed(tp); 1209 } 1210 return (tcp_output(tp)); 1211 } 1212 1213 #endif /* INET6 */ 1214 1215 /* 1216 * The new sockopt interface makes it possible for us to block in the 1217 * copyin/out step (if we take a page fault). Taking a page fault while 1218 * in a critical section is probably a Bad Thing. (Since sockets and pcbs 1219 * both now use TSM, there probably isn't any need for this function to 1220 * run in a critical section any more. This needs more examination.) 1221 */ 1222 int 1223 tcp_ctloutput(struct socket *so, struct sockopt *sopt) 1224 { 1225 int error, opt, optval; 1226 struct inpcb *inp; 1227 struct tcpcb *tp; 1228 1229 error = 0; 1230 crit_enter(); /* XXX */ 1231 inp = so->so_pcb; 1232 if (inp == NULL) { 1233 crit_exit(); 1234 return (ECONNRESET); 1235 } 1236 if (sopt->sopt_level != IPPROTO_TCP) { 1237 #ifdef INET6 1238 if (INP_CHECK_SOCKAF(so, AF_INET6)) 1239 error = ip6_ctloutput(so, sopt); 1240 else 1241 #endif /* INET6 */ 1242 error = ip_ctloutput(so, sopt); 1243 crit_exit(); 1244 return (error); 1245 } 1246 tp = intotcpcb(inp); 1247 1248 switch (sopt->sopt_dir) { 1249 case SOPT_SET: 1250 error = soopt_to_kbuf(sopt, &optval, sizeof optval, 1251 sizeof optval); 1252 if (error) 1253 break; 1254 switch (sopt->sopt_name) { 1255 case TCP_NODELAY: 1256 case TCP_NOOPT: 1257 switch (sopt->sopt_name) { 1258 case TCP_NODELAY: 1259 opt = TF_NODELAY; 1260 break; 1261 case TCP_NOOPT: 1262 opt = TF_NOOPT; 1263 break; 1264 default: 1265 opt = 0; /* dead code to fool gcc */ 1266 break; 1267 } 1268 1269 if (optval) 1270 tp->t_flags |= opt; 1271 else 1272 tp->t_flags &= ~opt; 1273 break; 1274 1275 case TCP_NOPUSH: 1276 if (optval) 1277 tp->t_flags |= TF_NOPUSH; 1278 else { 1279 tp->t_flags &= ~TF_NOPUSH; 1280 error = tcp_output(tp); 1281 } 1282 break; 1283 1284 case TCP_MAXSEG: 1285 /* 1286 * Must be between 0 and maxseg. If the requested 1287 * maxseg is too small to satisfy the desired minmss, 1288 * pump it up (silently so sysctl modifications of 1289 * minmss do not create unexpected program failures). 1290 * Handle degenerate cases. 1291 */ 1292 if (optval > 0 && optval <= tp->t_maxseg) { 1293 if (optval + 40 < tcp_minmss) { 1294 optval = tcp_minmss - 40; 1295 if (optval < 0) 1296 optval = 1; 1297 } 1298 tp->t_maxseg = optval; 1299 } else { 1300 error = EINVAL; 1301 } 1302 break; 1303 1304 default: 1305 error = ENOPROTOOPT; 1306 break; 1307 } 1308 break; 1309 1310 case SOPT_GET: 1311 switch (sopt->sopt_name) { 1312 case TCP_NODELAY: 1313 optval = tp->t_flags & TF_NODELAY; 1314 break; 1315 case TCP_MAXSEG: 1316 optval = tp->t_maxseg; 1317 break; 1318 case TCP_NOOPT: 1319 optval = tp->t_flags & TF_NOOPT; 1320 break; 1321 case TCP_NOPUSH: 1322 optval = tp->t_flags & TF_NOPUSH; 1323 break; 1324 default: 1325 error = ENOPROTOOPT; 1326 break; 1327 } 1328 if (error == 0) 1329 soopt_from_kbuf(sopt, &optval, sizeof optval); 1330 break; 1331 } 1332 crit_exit(); 1333 return (error); 1334 } 1335 1336 /* 1337 * tcp_sendspace and tcp_recvspace are the default send and receive window 1338 * sizes, respectively. These are obsolescent (this information should 1339 * be set by the route). 1340 * 1341 * Use a default that does not require tcp window scaling to be turned 1342 * on. Individual programs or the administrator can increase the default. 1343 */ 1344 u_long tcp_sendspace = 57344; /* largest multiple of PAGE_SIZE < 64k */ 1345 SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW, 1346 &tcp_sendspace , 0, "Maximum outgoing TCP datagram size"); 1347 u_long tcp_recvspace = 57344; /* largest multiple of PAGE_SIZE < 64k */ 1348 SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 1349 &tcp_recvspace , 0, "Maximum incoming TCP datagram size"); 1350 1351 /* 1352 * Attach TCP protocol to socket, allocating 1353 * internet protocol control block, tcp control block, 1354 * bufer space, and entering LISTEN state if to accept connections. 1355 */ 1356 static int 1357 tcp_attach(struct socket *so, struct pru_attach_info *ai) 1358 { 1359 struct tcpcb *tp; 1360 struct inpcb *inp; 1361 int error; 1362 int cpu; 1363 #ifdef INET6 1364 int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0; 1365 #endif 1366 1367 if (so->so_snd.ssb_hiwat == 0 || so->so_rcv.ssb_hiwat == 0) { 1368 error = soreserve(so, tcp_sendspace, tcp_recvspace, 1369 ai->sb_rlimit); 1370 if (error) 1371 return (error); 1372 } 1373 so->so_rcv.ssb_flags |= SSB_AUTOSIZE; 1374 so->so_snd.ssb_flags |= SSB_AUTOSIZE; 1375 cpu = mycpu->gd_cpuid; 1376 error = in_pcballoc(so, &tcbinfo[cpu]); 1377 if (error) 1378 return (error); 1379 inp = so->so_pcb; 1380 #ifdef INET6 1381 if (isipv6) { 1382 inp->inp_vflag |= INP_IPV6; 1383 inp->in6p_hops = -1; /* use kernel default */ 1384 } 1385 else 1386 #endif 1387 inp->inp_vflag |= INP_IPV4; 1388 tp = tcp_newtcpcb(inp); 1389 if (tp == 0) { 1390 int nofd = so->so_state & SS_NOFDREF; /* XXX */ 1391 1392 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */ 1393 #ifdef INET6 1394 if (isipv6) 1395 in6_pcbdetach(inp); 1396 else 1397 #endif 1398 in_pcbdetach(inp); 1399 so->so_state |= nofd; 1400 return (ENOBUFS); 1401 } 1402 tp->t_state = TCPS_CLOSED; 1403 so->so_port = tcp_soport_attach(so); 1404 return (0); 1405 } 1406 1407 /* 1408 * Initiate (or continue) disconnect. 1409 * If embryonic state, just send reset (once). 1410 * If in ``let data drain'' option and linger null, just drop. 1411 * Otherwise (hard), mark socket disconnecting and drop 1412 * current input data; switch states based on user close, and 1413 * send segment to peer (with FIN). 1414 */ 1415 static struct tcpcb * 1416 tcp_disconnect(struct tcpcb *tp) 1417 { 1418 struct socket *so = tp->t_inpcb->inp_socket; 1419 1420 if (tp->t_state < TCPS_ESTABLISHED) 1421 tp = tcp_close(tp); 1422 else if ((so->so_options & SO_LINGER) && so->so_linger == 0) 1423 tp = tcp_drop(tp, 0); 1424 else { 1425 soisdisconnecting(so); 1426 sbflush(&so->so_rcv.sb); 1427 tp = tcp_usrclosed(tp); 1428 if (tp) 1429 tcp_output(tp); 1430 } 1431 return (tp); 1432 } 1433 1434 /* 1435 * User issued close, and wish to trail through shutdown states: 1436 * if never received SYN, just forget it. If got a SYN from peer, 1437 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. 1438 * If already got a FIN from peer, then almost done; go to LAST_ACK 1439 * state. In all other cases, have already sent FIN to peer (e.g. 1440 * after PRU_SHUTDOWN), and just have to play tedious game waiting 1441 * for peer to send FIN or not respond to keep-alives, etc. 1442 * We can let the user exit from the close as soon as the FIN is acked. 1443 */ 1444 static struct tcpcb * 1445 tcp_usrclosed(struct tcpcb *tp) 1446 { 1447 1448 switch (tp->t_state) { 1449 1450 case TCPS_CLOSED: 1451 case TCPS_LISTEN: 1452 tp->t_state = TCPS_CLOSED; 1453 tp = tcp_close(tp); 1454 break; 1455 1456 case TCPS_SYN_SENT: 1457 case TCPS_SYN_RECEIVED: 1458 tp->t_flags |= TF_NEEDFIN; 1459 break; 1460 1461 case TCPS_ESTABLISHED: 1462 tp->t_state = TCPS_FIN_WAIT_1; 1463 break; 1464 1465 case TCPS_CLOSE_WAIT: 1466 tp->t_state = TCPS_LAST_ACK; 1467 break; 1468 } 1469 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) { 1470 soisdisconnected(tp->t_inpcb->inp_socket); 1471 /* To prevent the connection hanging in FIN_WAIT_2 forever. */ 1472 if (tp->t_state == TCPS_FIN_WAIT_2) { 1473 tcp_callout_reset(tp, tp->tt_2msl, tcp_maxidle, 1474 tcp_timer_2msl); 1475 } 1476 } 1477 return (tp); 1478 } 1479