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sys/netinet/tcp_usrreq.c
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1 /* 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94 34 * $FreeBSD: releng/5.0/sys/netinet/tcp_usrreq.c 105840 2002-10-24 02:02:34Z iedowse $ 35 */ 36 37 #include "opt_ipsec.h" 38 #include "opt_inet6.h" 39 #include "opt_tcpdebug.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/kernel.h> 45 #include <sys/sysctl.h> 46 #include <sys/mbuf.h> 47 #ifdef INET6 48 #include <sys/domain.h> 49 #endif /* INET6 */ 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/protosw.h> 53 #include <sys/proc.h> 54 #include <sys/jail.h> 55 56 #include <net/if.h> 57 #include <net/route.h> 58 59 #include <netinet/in.h> 60 #include <netinet/in_systm.h> 61 #ifdef INET6 62 #include <netinet/ip6.h> 63 #endif 64 #include <netinet/in_pcb.h> 65 #ifdef INET6 66 #include <netinet6/in6_pcb.h> 67 #endif 68 #include <netinet/in_var.h> 69 #include <netinet/ip_var.h> 70 #ifdef INET6 71 #include <netinet6/ip6_var.h> 72 #endif 73 #include <netinet/tcp.h> 74 #include <netinet/tcp_fsm.h> 75 #include <netinet/tcp_seq.h> 76 #include <netinet/tcp_timer.h> 77 #include <netinet/tcp_var.h> 78 #include <netinet/tcpip.h> 79 #ifdef TCPDEBUG 80 #include <netinet/tcp_debug.h> 81 #endif 82 83 #ifdef IPSEC 84 #include <netinet6/ipsec.h> 85 #endif /*IPSEC*/ 86 87 /* 88 * TCP protocol interface to socket abstraction. 89 */ 90 extern char *tcpstates[]; /* XXX ??? */ 91 92 static int tcp_attach(struct socket *, struct thread *td); 93 static int tcp_connect(struct tcpcb *, struct sockaddr *, 94 struct thread *td); 95 #ifdef INET6 96 static int tcp6_connect(struct tcpcb *, struct sockaddr *, 97 struct thread *td); 98 #endif /* INET6 */ 99 static struct tcpcb * 100 tcp_disconnect(struct tcpcb *); 101 static struct tcpcb * 102 tcp_usrclosed(struct tcpcb *); 103 104 #ifdef TCPDEBUG 105 #define TCPDEBUG0 int ostate = 0 106 #define TCPDEBUG1() ostate = tp ? tp->t_state : 0 107 #define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \ 108 tcp_trace(TA_USER, ostate, tp, 0, 0, req) 109 #else 110 #define TCPDEBUG0 111 #define TCPDEBUG1() 112 #define TCPDEBUG2(req) 113 #endif 114 115 /* 116 * TCP attaches to socket via pru_attach(), reserving space, 117 * and an internet control block. 118 */ 119 static int 120 tcp_usr_attach(struct socket *so, int proto, struct thread *td) 121 { 122 int s = splnet(); 123 int error; 124 struct inpcb *inp; 125 struct tcpcb *tp = 0; 126 TCPDEBUG0; 127 128 INP_INFO_WLOCK(&tcbinfo); 129 TCPDEBUG1(); 130 inp = sotoinpcb(so); 131 if (inp) { 132 error = EISCONN; 133 goto out; 134 } 135 136 error = tcp_attach(so, td); 137 if (error) 138 goto out; 139 140 if ((so->so_options & SO_LINGER) && so->so_linger == 0) 141 so->so_linger = TCP_LINGERTIME; 142 143 inp = sotoinpcb(so); 144 tp = intotcpcb(inp); 145 out: 146 TCPDEBUG2(PRU_ATTACH); 147 INP_INFO_WUNLOCK(&tcbinfo); 148 splx(s); 149 return error; 150 } 151 152 /* 153 * pru_detach() detaches the TCP protocol from the socket. 154 * If the protocol state is non-embryonic, then can't 155 * do this directly: have to initiate a pru_disconnect(), 156 * which may finish later; embryonic TCB's can just 157 * be discarded here. 158 */ 159 static int 160 tcp_usr_detach(struct socket *so) 161 { 162 int s = splnet(); 163 int error = 0; 164 struct inpcb *inp; 165 struct tcpcb *tp; 166 TCPDEBUG0; 167 168 INP_INFO_WLOCK(&tcbinfo); 169 inp = sotoinpcb(so); 170 if (inp == 0) { 171 INP_INFO_WUNLOCK(&tcbinfo); 172 splx(s); 173 return EINVAL; /* XXX */ 174 } 175 INP_LOCK(inp); 176 tp = intotcpcb(inp); 177 TCPDEBUG1(); 178 tp = tcp_disconnect(tp); 179 180 TCPDEBUG2(PRU_DETACH); 181 if (tp) 182 INP_UNLOCK(inp); 183 INP_INFO_WUNLOCK(&tcbinfo); 184 splx(s); 185 return error; 186 } 187 188 #define INI_NOLOCK 0 189 #define INI_READ 1 190 #define INI_WRITE 2 191 192 #define COMMON_START() \ 193 TCPDEBUG0; \ 194 do { \ 195 if (inirw == INI_READ) \ 196 INP_INFO_RLOCK(&tcbinfo); \ 197 else if (inirw == INI_WRITE) \ 198 INP_INFO_WLOCK(&tcbinfo); \ 199 inp = sotoinpcb(so); \ 200 if (inp == 0) { \ 201 if (inirw == INI_READ) \ 202 INP_INFO_RUNLOCK(&tcbinfo); \ 203 else if (inirw == INI_WRITE) \ 204 INP_INFO_WUNLOCK(&tcbinfo); \ 205 splx(s); \ 206 return EINVAL; \ 207 } \ 208 INP_LOCK(inp); \ 209 if (inirw == INI_READ) \ 210 INP_INFO_RUNLOCK(&tcbinfo); \ 211 tp = intotcpcb(inp); \ 212 TCPDEBUG1(); \ 213 } while(0) 214 215 #define COMMON_END(req) \ 216 out: TCPDEBUG2(req); \ 217 do { \ 218 if (tp) \ 219 INP_UNLOCK(inp); \ 220 if (inirw == INI_WRITE) \ 221 INP_INFO_WUNLOCK(&tcbinfo); \ 222 splx(s); \ 223 return error; \ 224 goto out; \ 225 } while(0) 226 227 /* 228 * Give the socket an address. 229 */ 230 static int 231 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 232 { 233 int s = splnet(); 234 int error = 0; 235 struct inpcb *inp; 236 struct tcpcb *tp; 237 struct sockaddr_in *sinp; 238 const int inirw = INI_READ; 239 240 COMMON_START(); 241 242 /* 243 * Must check for multicast addresses and disallow binding 244 * to them. 245 */ 246 sinp = (struct sockaddr_in *)nam; 247 if (sinp->sin_family == AF_INET && 248 IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { 249 error = EAFNOSUPPORT; 250 goto out; 251 } 252 error = in_pcbbind(inp, nam, td); 253 if (error) 254 goto out; 255 COMMON_END(PRU_BIND); 256 } 257 258 #ifdef INET6 259 static int 260 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 261 { 262 int s = splnet(); 263 int error = 0; 264 struct inpcb *inp; 265 struct tcpcb *tp; 266 struct sockaddr_in6 *sin6p; 267 const int inirw = INI_READ; 268 269 COMMON_START(); 270 271 /* 272 * Must check for multicast addresses and disallow binding 273 * to them. 274 */ 275 sin6p = (struct sockaddr_in6 *)nam; 276 if (sin6p->sin6_family == AF_INET6 && 277 IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) { 278 error = EAFNOSUPPORT; 279 goto out; 280 } 281 inp->inp_vflag &= ~INP_IPV4; 282 inp->inp_vflag |= INP_IPV6; 283 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) { 284 if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr)) 285 inp->inp_vflag |= INP_IPV4; 286 else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { 287 struct sockaddr_in sin; 288 289 in6_sin6_2_sin(&sin, sin6p); 290 inp->inp_vflag |= INP_IPV4; 291 inp->inp_vflag &= ~INP_IPV6; 292 error = in_pcbbind(inp, (struct sockaddr *)&sin, td); 293 goto out; 294 } 295 } 296 error = in6_pcbbind(inp, nam, td); 297 if (error) 298 goto out; 299 COMMON_END(PRU_BIND); 300 } 301 #endif /* INET6 */ 302 303 /* 304 * Prepare to accept connections. 305 */ 306 static int 307 tcp_usr_listen(struct socket *so, struct thread *td) 308 { 309 int s = splnet(); 310 int error = 0; 311 struct inpcb *inp; 312 struct tcpcb *tp; 313 const int inirw = INI_READ; 314 315 COMMON_START(); 316 if (inp->inp_lport == 0) 317 error = in_pcbbind(inp, (struct sockaddr *)0, td); 318 if (error == 0) 319 tp->t_state = TCPS_LISTEN; 320 COMMON_END(PRU_LISTEN); 321 } 322 323 #ifdef INET6 324 static int 325 tcp6_usr_listen(struct socket *so, struct thread *td) 326 { 327 int s = splnet(); 328 int error = 0; 329 struct inpcb *inp; 330 struct tcpcb *tp; 331 const int inirw = INI_READ; 332 333 COMMON_START(); 334 if (inp->inp_lport == 0) { 335 inp->inp_vflag &= ~INP_IPV4; 336 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) 337 inp->inp_vflag |= INP_IPV4; 338 error = in6_pcbbind(inp, (struct sockaddr *)0, td); 339 } 340 if (error == 0) 341 tp->t_state = TCPS_LISTEN; 342 COMMON_END(PRU_LISTEN); 343 } 344 #endif /* INET6 */ 345 346 /* 347 * Initiate connection to peer. 348 * Create a template for use in transmissions on this connection. 349 * Enter SYN_SENT state, and mark socket as connecting. 350 * Start keep-alive timer, and seed output sequence space. 351 * Send initial segment on connection. 352 */ 353 static int 354 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 355 { 356 int s = splnet(); 357 int error = 0; 358 struct inpcb *inp; 359 struct tcpcb *tp; 360 struct sockaddr_in *sinp; 361 const int inirw = INI_WRITE; 362 363 COMMON_START(); 364 365 /* 366 * Must disallow TCP ``connections'' to multicast addresses. 367 */ 368 sinp = (struct sockaddr_in *)nam; 369 if (sinp->sin_family == AF_INET 370 && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { 371 error = EAFNOSUPPORT; 372 goto out; 373 } 374 375 if (td && jailed(td->td_ucred)) 376 prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr); 377 378 if ((error = tcp_connect(tp, nam, td)) != 0) 379 goto out; 380 error = tcp_output(tp); 381 COMMON_END(PRU_CONNECT); 382 } 383 384 #ifdef INET6 385 static int 386 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 387 { 388 int s = splnet(); 389 int error = 0; 390 struct inpcb *inp; 391 struct tcpcb *tp; 392 struct sockaddr_in6 *sin6p; 393 const int inirw = INI_WRITE; 394 395 COMMON_START(); 396 397 /* 398 * Must disallow TCP ``connections'' to multicast addresses. 399 */ 400 sin6p = (struct sockaddr_in6 *)nam; 401 if (sin6p->sin6_family == AF_INET6 402 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) { 403 error = EAFNOSUPPORT; 404 goto out; 405 } 406 407 if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { 408 struct sockaddr_in sin; 409 410 if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) { 411 error = EINVAL; 412 goto out; 413 } 414 415 in6_sin6_2_sin(&sin, sin6p); 416 inp->inp_vflag |= INP_IPV4; 417 inp->inp_vflag &= ~INP_IPV6; 418 if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0) 419 goto out; 420 error = tcp_output(tp); 421 goto out; 422 } 423 inp->inp_vflag &= ~INP_IPV4; 424 inp->inp_vflag |= INP_IPV6; 425 inp->inp_inc.inc_isipv6 = 1; 426 if ((error = tcp6_connect(tp, nam, td)) != 0) 427 goto out; 428 error = tcp_output(tp); 429 COMMON_END(PRU_CONNECT); 430 } 431 #endif /* INET6 */ 432 433 /* 434 * Initiate disconnect from peer. 435 * If connection never passed embryonic stage, just drop; 436 * else if don't need to let data drain, then can just drop anyways, 437 * else have to begin TCP shutdown process: mark socket disconnecting, 438 * drain unread data, state switch to reflect user close, and 439 * send segment (e.g. FIN) to peer. Socket will be really disconnected 440 * when peer sends FIN and acks ours. 441 * 442 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB. 443 */ 444 static int 445 tcp_usr_disconnect(struct socket *so) 446 { 447 int s = splnet(); 448 int error = 0; 449 struct inpcb *inp; 450 struct tcpcb *tp; 451 const int inirw = INI_WRITE; 452 453 COMMON_START(); 454 tp = tcp_disconnect(tp); 455 COMMON_END(PRU_DISCONNECT); 456 } 457 458 /* 459 * Accept a connection. Essentially all the work is 460 * done at higher levels; just return the address 461 * of the peer, storing through addr. 462 */ 463 static int 464 tcp_usr_accept(struct socket *so, struct sockaddr **nam) 465 { 466 int s; 467 int error = 0; 468 struct inpcb *inp = NULL; 469 struct tcpcb *tp = NULL; 470 struct in_addr addr; 471 in_port_t port = 0; 472 TCPDEBUG0; 473 474 if (so->so_state & SS_ISDISCONNECTED) { 475 error = ECONNABORTED; 476 goto out; 477 } 478 479 s = splnet(); 480 INP_INFO_RLOCK(&tcbinfo); 481 inp = sotoinpcb(so); 482 if (!inp) { 483 INP_INFO_RUNLOCK(&tcbinfo); 484 splx(s); 485 return (EINVAL); 486 } 487 INP_LOCK(inp); 488 INP_INFO_RUNLOCK(&tcbinfo); 489 tp = intotcpcb(inp); 490 TCPDEBUG1(); 491 492 /* 493 * We inline in_setpeeraddr and COMMON_END here, so that we can 494 * copy the data of interest and defer the malloc until after we 495 * release the lock. 496 */ 497 port = inp->inp_fport; 498 addr = inp->inp_faddr; 499 500 out: TCPDEBUG2(PRU_ACCEPT); 501 if (tp) 502 INP_UNLOCK(inp); 503 splx(s); 504 if (error == 0) 505 *nam = in_sockaddr(port, &addr); 506 return error; 507 } 508 509 #ifdef INET6 510 static int 511 tcp6_usr_accept(struct socket *so, struct sockaddr **nam) 512 { 513 int s; 514 struct inpcb *inp = NULL; 515 int error = 0; 516 struct tcpcb *tp = NULL; 517 struct in_addr addr; 518 struct in6_addr addr6; 519 in_port_t port = 0; 520 int v4 = 0; 521 TCPDEBUG0; 522 523 if (so->so_state & SS_ISDISCONNECTED) { 524 error = ECONNABORTED; 525 goto out; 526 } 527 528 s = splnet(); 529 INP_INFO_RLOCK(&tcbinfo); 530 inp = sotoinpcb(so); 531 if (inp == 0) { 532 INP_INFO_RUNLOCK(&tcbinfo); 533 splx(s); 534 return (EINVAL); 535 } 536 INP_LOCK(inp); 537 INP_INFO_RUNLOCK(&tcbinfo); 538 tp = intotcpcb(inp); 539 TCPDEBUG1(); 540 /* 541 * We inline in6_mapped_peeraddr and COMMON_END here, so that we can 542 * copy the data of interest and defer the malloc until after we 543 * release the lock. 544 */ 545 if (inp->inp_vflag & INP_IPV4) { 546 v4 = 1; 547 port = inp->inp_fport; 548 addr = inp->inp_faddr; 549 } else { 550 port = inp->inp_fport; 551 addr6 = inp->in6p_faddr; 552 } 553 554 out: TCPDEBUG2(PRU_ACCEPT); 555 if (tp) 556 INP_UNLOCK(inp); 557 splx(s); 558 if (error == 0) { 559 if (v4) 560 *nam = in6_v4mapsin6_sockaddr(port, &addr); 561 else 562 *nam = in6_sockaddr(port, &addr6); 563 } 564 return error; 565 } 566 #endif /* INET6 */ 567 568 /* 569 * This is the wrapper function for in_setsockaddr. We just pass down 570 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking 571 * here because in_setsockaddr will call malloc and can block. 572 */ 573 static int 574 tcp_sockaddr(struct socket *so, struct sockaddr **nam) 575 { 576 return (in_setsockaddr(so, nam, &tcbinfo)); 577 } 578 579 /* 580 * This is the wrapper function for in_setpeeraddr. We just pass down 581 * the pcbinfo for in_setpeeraddr to lock. 582 */ 583 static int 584 tcp_peeraddr(struct socket *so, struct sockaddr **nam) 585 { 586 return (in_setpeeraddr(so, nam, &tcbinfo)); 587 } 588 589 /* 590 * Mark the connection as being incapable of further output. 591 */ 592 static int 593 tcp_usr_shutdown(struct socket *so) 594 { 595 int s = splnet(); 596 int error = 0; 597 struct inpcb *inp; 598 struct tcpcb *tp; 599 const int inirw = INI_WRITE; 600 601 COMMON_START(); 602 socantsendmore(so); 603 tp = tcp_usrclosed(tp); 604 if (tp) 605 error = tcp_output(tp); 606 COMMON_END(PRU_SHUTDOWN); 607 } 608 609 /* 610 * After a receive, possibly send window update to peer. 611 */ 612 static int 613 tcp_usr_rcvd(struct socket *so, int flags) 614 { 615 int s = splnet(); 616 int error = 0; 617 struct inpcb *inp; 618 struct tcpcb *tp; 619 const int inirw = INI_READ; 620 621 COMMON_START(); 622 tcp_output(tp); 623 COMMON_END(PRU_RCVD); 624 } 625 626 /* 627 * Do a send by putting data in output queue and updating urgent 628 * marker if URG set. Possibly send more data. Unlike the other 629 * pru_*() routines, the mbuf chains are our responsibility. We 630 * must either enqueue them or free them. The other pru_* routines 631 * generally are caller-frees. 632 */ 633 static int 634 tcp_usr_send(struct socket *so, int flags, struct mbuf *m, 635 struct sockaddr *nam, struct mbuf *control, struct thread *td) 636 { 637 int s = splnet(); 638 int error = 0; 639 struct inpcb *inp; 640 struct tcpcb *tp; 641 const int inirw = INI_WRITE; 642 #ifdef INET6 643 int isipv6; 644 #endif 645 TCPDEBUG0; 646 647 /* 648 * Need write lock here because this function might call 649 * tcp_connect or tcp_usrclosed. 650 * We really want to have to this function upgrade from read lock 651 * to write lock. XXX 652 */ 653 INP_INFO_WLOCK(&tcbinfo); 654 inp = sotoinpcb(so); 655 if (inp == NULL) { 656 /* 657 * OOPS! we lost a race, the TCP session got reset after 658 * we checked SS_CANTSENDMORE, eg: while doing uiomove or a 659 * network interrupt in the non-splnet() section of sosend(). 660 */ 661 if (m) 662 m_freem(m); 663 if (control) 664 m_freem(control); 665 error = ECONNRESET; /* XXX EPIPE? */ 666 tp = NULL; 667 TCPDEBUG1(); 668 goto out; 669 } 670 INP_LOCK(inp); 671 #ifdef INET6 672 isipv6 = nam && nam->sa_family == AF_INET6; 673 #endif /* INET6 */ 674 tp = intotcpcb(inp); 675 TCPDEBUG1(); 676 if (control) { 677 /* TCP doesn't do control messages (rights, creds, etc) */ 678 if (control->m_len) { 679 m_freem(control); 680 if (m) 681 m_freem(m); 682 error = EINVAL; 683 goto out; 684 } 685 m_freem(control); /* empty control, just free it */ 686 } 687 if (!(flags & PRUS_OOB)) { 688 sbappend(&so->so_snd, m); 689 if (nam && tp->t_state < TCPS_SYN_SENT) { 690 /* 691 * Do implied connect if not yet connected, 692 * initialize window to default value, and 693 * initialize maxseg/maxopd using peer's cached 694 * MSS. 695 */ 696 #ifdef INET6 697 if (isipv6) 698 error = tcp6_connect(tp, nam, td); 699 else 700 #endif /* INET6 */ 701 error = tcp_connect(tp, nam, td); 702 if (error) 703 goto out; 704 tp->snd_wnd = TTCP_CLIENT_SND_WND; 705 tcp_mss(tp, -1); 706 } 707 708 if (flags & PRUS_EOF) { 709 /* 710 * Close the send side of the connection after 711 * the data is sent. 712 */ 713 socantsendmore(so); 714 tp = tcp_usrclosed(tp); 715 } 716 if (tp != NULL) { 717 if (flags & PRUS_MORETOCOME) 718 tp->t_flags |= TF_MORETOCOME; 719 error = tcp_output(tp); 720 if (flags & PRUS_MORETOCOME) 721 tp->t_flags &= ~TF_MORETOCOME; 722 } 723 } else { 724 if (sbspace(&so->so_snd) < -512) { 725 m_freem(m); 726 error = ENOBUFS; 727 goto out; 728 } 729 /* 730 * According to RFC961 (Assigned Protocols), 731 * the urgent pointer points to the last octet 732 * of urgent data. We continue, however, 733 * to consider it to indicate the first octet 734 * of data past the urgent section. 735 * Otherwise, snd_up should be one lower. 736 */ 737 sbappend(&so->so_snd, m); 738 if (nam && tp->t_state < TCPS_SYN_SENT) { 739 /* 740 * Do implied connect if not yet connected, 741 * initialize window to default value, and 742 * initialize maxseg/maxopd using peer's cached 743 * MSS. 744 */ 745 #ifdef INET6 746 if (isipv6) 747 error = tcp6_connect(tp, nam, td); 748 else 749 #endif /* INET6 */ 750 error = tcp_connect(tp, nam, td); 751 if (error) 752 goto out; 753 tp->snd_wnd = TTCP_CLIENT_SND_WND; 754 tcp_mss(tp, -1); 755 } 756 tp->snd_up = tp->snd_una + so->so_snd.sb_cc; 757 tp->t_force = 1; 758 error = tcp_output(tp); 759 tp->t_force = 0; 760 } 761 COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB : 762 ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND)); 763 } 764 765 /* 766 * Abort the TCP. 767 */ 768 static int 769 tcp_usr_abort(struct socket *so) 770 { 771 int s = splnet(); 772 int error = 0; 773 struct inpcb *inp; 774 struct tcpcb *tp; 775 const int inirw = INI_WRITE; 776 777 COMMON_START(); 778 tp = tcp_drop(tp, ECONNABORTED); 779 COMMON_END(PRU_ABORT); 780 } 781 782 /* 783 * Receive out-of-band data. 784 */ 785 static int 786 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags) 787 { 788 int s = splnet(); 789 int error = 0; 790 struct inpcb *inp; 791 struct tcpcb *tp; 792 const int inirw = INI_READ; 793 794 COMMON_START(); 795 if ((so->so_oobmark == 0 && 796 (so->so_state & SS_RCVATMARK) == 0) || 797 so->so_options & SO_OOBINLINE || 798 tp->t_oobflags & TCPOOB_HADDATA) { 799 error = EINVAL; 800 goto out; 801 } 802 if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { 803 error = EWOULDBLOCK; 804 goto out; 805 } 806 m->m_len = 1; 807 *mtod(m, caddr_t) = tp->t_iobc; 808 if ((flags & MSG_PEEK) == 0) 809 tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); 810 COMMON_END(PRU_RCVOOB); 811 } 812 813 /* xxx - should be const */ 814 struct pr_usrreqs tcp_usrreqs = { 815 tcp_usr_abort, tcp_usr_accept, tcp_usr_attach, tcp_usr_bind, 816 tcp_usr_connect, pru_connect2_notsupp, in_control, tcp_usr_detach, 817 tcp_usr_disconnect, tcp_usr_listen, tcp_peeraddr, tcp_usr_rcvd, 818 tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown, 819 tcp_sockaddr, sosend, soreceive, sopoll 820 }; 821 822 #ifdef INET6 823 struct pr_usrreqs tcp6_usrreqs = { 824 tcp_usr_abort, tcp6_usr_accept, tcp_usr_attach, tcp6_usr_bind, 825 tcp6_usr_connect, pru_connect2_notsupp, in6_control, tcp_usr_detach, 826 tcp_usr_disconnect, tcp6_usr_listen, in6_mapped_peeraddr, tcp_usr_rcvd, 827 tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown, 828 in6_mapped_sockaddr, sosend, soreceive, sopoll 829 }; 830 #endif /* INET6 */ 831 832 /* 833 * Common subroutine to open a TCP connection to remote host specified 834 * by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local 835 * port number if needed. Call in_pcbconnect_setup to do the routing and 836 * to choose a local host address (interface). If there is an existing 837 * incarnation of the same connection in TIME-WAIT state and if the remote 838 * host was sending CC options and if the connection duration was < MSL, then 839 * truncate the previous TIME-WAIT state and proceed. 840 * Initialize connection parameters and enter SYN-SENT state. 841 */ 842 static int 843 tcp_connect(tp, nam, td) 844 register struct tcpcb *tp; 845 struct sockaddr *nam; 846 struct thread *td; 847 { 848 struct inpcb *inp = tp->t_inpcb, *oinp; 849 struct socket *so = inp->inp_socket; 850 struct tcpcb *otp; 851 struct rmxp_tao *taop; 852 struct rmxp_tao tao_noncached; 853 struct in_addr laddr; 854 u_short lport; 855 int error; 856 857 if (inp->inp_lport == 0) { 858 error = in_pcbbind(inp, (struct sockaddr *)0, td); 859 if (error) 860 return error; 861 } 862 863 /* 864 * Cannot simply call in_pcbconnect, because there might be an 865 * earlier incarnation of this same connection still in 866 * TIME_WAIT state, creating an ADDRINUSE error. 867 */ 868 laddr = inp->inp_laddr; 869 lport = inp->inp_lport; 870 error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport, 871 &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td); 872 if (error && oinp == NULL) 873 return error; 874 if (oinp) { 875 if (oinp != inp && (otp = intotcpcb(oinp)) != NULL && 876 otp->t_state == TCPS_TIME_WAIT && 877 (ticks - otp->t_starttime) < tcp_msl && 878 (otp->t_flags & TF_RCVD_CC)) { 879 inp->inp_faddr = oinp->inp_faddr; 880 inp->inp_fport = oinp->inp_fport; 881 otp = tcp_close(otp); 882 } else 883 return EADDRINUSE; 884 } 885 inp->inp_laddr = laddr; 886 in_pcbrehash(inp); 887 888 /* Compute window scaling to request. */ 889 while (tp->request_r_scale < TCP_MAX_WINSHIFT && 890 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat) 891 tp->request_r_scale++; 892 893 soisconnecting(so); 894 tcpstat.tcps_connattempt++; 895 tp->t_state = TCPS_SYN_SENT; 896 callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp); 897 tp->iss = tcp_new_isn(tp); 898 tp->t_bw_rtseq = tp->iss; 899 tcp_sendseqinit(tp); 900 901 /* 902 * Generate a CC value for this connection and 903 * check whether CC or CCnew should be used. 904 */ 905 if ((taop = tcp_gettaocache(&tp->t_inpcb->inp_inc)) == NULL) { 906 taop = &tao_noncached; 907 bzero(taop, sizeof(*taop)); 908 } 909 910 tp->cc_send = CC_INC(tcp_ccgen); 911 if (taop->tao_ccsent != 0 && 912 CC_GEQ(tp->cc_send, taop->tao_ccsent)) { 913 taop->tao_ccsent = tp->cc_send; 914 } else { 915 taop->tao_ccsent = 0; 916 tp->t_flags |= TF_SENDCCNEW; 917 } 918 919 return 0; 920 } 921 922 #ifdef INET6 923 static int 924 tcp6_connect(tp, nam, td) 925 register struct tcpcb *tp; 926 struct sockaddr *nam; 927 struct thread *td; 928 { 929 struct inpcb *inp = tp->t_inpcb, *oinp; 930 struct socket *so = inp->inp_socket; 931 struct tcpcb *otp; 932 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam; 933 struct in6_addr *addr6; 934 struct rmxp_tao *taop; 935 struct rmxp_tao tao_noncached; 936 int error; 937 938 if (inp->inp_lport == 0) { 939 error = in6_pcbbind(inp, (struct sockaddr *)0, td); 940 if (error) 941 return error; 942 } 943 944 /* 945 * Cannot simply call in_pcbconnect, because there might be an 946 * earlier incarnation of this same connection still in 947 * TIME_WAIT state, creating an ADDRINUSE error. 948 */ 949 error = in6_pcbladdr(inp, nam, &addr6); 950 if (error) 951 return error; 952 oinp = in6_pcblookup_hash(inp->inp_pcbinfo, 953 &sin6->sin6_addr, sin6->sin6_port, 954 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) 955 ? addr6 956 : &inp->in6p_laddr, 957 inp->inp_lport, 0, NULL); 958 if (oinp) { 959 if (oinp != inp && (otp = intotcpcb(oinp)) != NULL && 960 otp->t_state == TCPS_TIME_WAIT && 961 (ticks - otp->t_starttime) < tcp_msl && 962 (otp->t_flags & TF_RCVD_CC)) 963 otp = tcp_close(otp); 964 else 965 return EADDRINUSE; 966 } 967 if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) 968 inp->in6p_laddr = *addr6; 969 inp->in6p_faddr = sin6->sin6_addr; 970 inp->inp_fport = sin6->sin6_port; 971 if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0) 972 inp->in6p_flowinfo = sin6->sin6_flowinfo; 973 in_pcbrehash(inp); 974 975 /* Compute window scaling to request. */ 976 while (tp->request_r_scale < TCP_MAX_WINSHIFT && 977 (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat) 978 tp->request_r_scale++; 979 980 soisconnecting(so); 981 tcpstat.tcps_connattempt++; 982 tp->t_state = TCPS_SYN_SENT; 983 callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp); 984 tp->iss = tcp_new_isn(tp); 985 tp->t_bw_rtseq = tp->iss; 986 tcp_sendseqinit(tp); 987 988 /* 989 * Generate a CC value for this connection and 990 * check whether CC or CCnew should be used. 991 */ 992 if ((taop = tcp_gettaocache(&tp->t_inpcb->inp_inc)) == NULL) { 993 taop = &tao_noncached; 994 bzero(taop, sizeof(*taop)); 995 } 996 997 tp->cc_send = CC_INC(tcp_ccgen); 998 if (taop->tao_ccsent != 0 && 999 CC_GEQ(tp->cc_send, taop->tao_ccsent)) { 1000 taop->tao_ccsent = tp->cc_send; 1001 } else { 1002 taop->tao_ccsent = 0; 1003 tp->t_flags |= TF_SENDCCNEW; 1004 } 1005 1006 return 0; 1007 } 1008 #endif /* INET6 */ 1009 1010 /* 1011 * The new sockopt interface makes it possible for us to block in the 1012 * copyin/out step (if we take a page fault). Taking a page fault at 1013 * splnet() is probably a Bad Thing. (Since sockets and pcbs both now 1014 * use TSM, there probably isn't any need for this function to run at 1015 * splnet() any more. This needs more examination.) 1016 */ 1017 int 1018 tcp_ctloutput(so, sopt) 1019 struct socket *so; 1020 struct sockopt *sopt; 1021 { 1022 int error, opt, optval, s; 1023 struct inpcb *inp; 1024 struct tcpcb *tp; 1025 1026 error = 0; 1027 s = splnet(); /* XXX */ 1028 INP_INFO_RLOCK(&tcbinfo); 1029 inp = sotoinpcb(so); 1030 if (inp == NULL) { 1031 INP_INFO_RUNLOCK(&tcbinfo); 1032 splx(s); 1033 return (ECONNRESET); 1034 } 1035 INP_LOCK(inp); 1036 INP_INFO_RUNLOCK(&tcbinfo); 1037 if (sopt->sopt_level != IPPROTO_TCP) { 1038 #ifdef INET6 1039 if (INP_CHECK_SOCKAF(so, AF_INET6)) 1040 error = ip6_ctloutput(so, sopt); 1041 else 1042 #endif /* INET6 */ 1043 error = ip_ctloutput(so, sopt); 1044 INP_UNLOCK(inp); 1045 splx(s); 1046 return (error); 1047 } 1048 tp = intotcpcb(inp); 1049 1050 switch (sopt->sopt_dir) { 1051 case SOPT_SET: 1052 switch (sopt->sopt_name) { 1053 case TCP_NODELAY: 1054 case TCP_NOOPT: 1055 error = sooptcopyin(sopt, &optval, sizeof optval, 1056 sizeof optval); 1057 if (error) 1058 break; 1059 1060 switch (sopt->sopt_name) { 1061 case TCP_NODELAY: 1062 opt = TF_NODELAY; 1063 break; 1064 case TCP_NOOPT: 1065 opt = TF_NOOPT; 1066 break; 1067 default: 1068 opt = 0; /* dead code to fool gcc */ 1069 break; 1070 } 1071 1072 if (optval) 1073 tp->t_flags |= opt; 1074 else 1075 tp->t_flags &= ~opt; 1076 break; 1077 1078 case TCP_NOPUSH: 1079 error = sooptcopyin(sopt, &optval, sizeof optval, 1080 sizeof optval); 1081 if (error) 1082 break; 1083 1084 if (optval) 1085 tp->t_flags |= TF_NOPUSH; 1086 else { 1087 tp->t_flags &= ~TF_NOPUSH; 1088 error = tcp_output(tp); 1089 } 1090 break; 1091 1092 case TCP_MAXSEG: 1093 error = sooptcopyin(sopt, &optval, sizeof optval, 1094 sizeof optval); 1095 if (error) 1096 break; 1097 1098 if (optval > 0 && optval <= tp->t_maxseg) 1099 tp->t_maxseg = optval; 1100 else 1101 error = EINVAL; 1102 break; 1103 1104 default: 1105 error = ENOPROTOOPT; 1106 break; 1107 } 1108 break; 1109 1110 case SOPT_GET: 1111 switch (sopt->sopt_name) { 1112 case TCP_NODELAY: 1113 optval = tp->t_flags & TF_NODELAY; 1114 break; 1115 case TCP_MAXSEG: 1116 optval = tp->t_maxseg; 1117 break; 1118 case TCP_NOOPT: 1119 optval = tp->t_flags & TF_NOOPT; 1120 break; 1121 case TCP_NOPUSH: 1122 optval = tp->t_flags & TF_NOPUSH; 1123 break; 1124 default: 1125 error = ENOPROTOOPT; 1126 break; 1127 } 1128 if (error == 0) 1129 error = sooptcopyout(sopt, &optval, sizeof optval); 1130 break; 1131 } 1132 INP_UNLOCK(inp); 1133 splx(s); 1134 return (error); 1135 } 1136 1137 /* 1138 * tcp_sendspace and tcp_recvspace are the default send and receive window 1139 * sizes, respectively. These are obsolescent (this information should 1140 * be set by the route). 1141 */ 1142 u_long tcp_sendspace = 1024*32; 1143 SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW, 1144 &tcp_sendspace , 0, "Maximum outgoing TCP datagram size"); 1145 u_long tcp_recvspace = 1024*64; 1146 SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 1147 &tcp_recvspace , 0, "Maximum incoming TCP datagram size"); 1148 1149 /* 1150 * Attach TCP protocol to socket, allocating 1151 * internet protocol control block, tcp control block, 1152 * bufer space, and entering LISTEN state if to accept connections. 1153 */ 1154 static int 1155 tcp_attach(so, td) 1156 struct socket *so; 1157 struct thread *td; 1158 { 1159 register struct tcpcb *tp; 1160 struct inpcb *inp; 1161 int error; 1162 #ifdef INET6 1163 int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0; 1164 #endif 1165 1166 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 1167 error = soreserve(so, tcp_sendspace, tcp_recvspace); 1168 if (error) 1169 return (error); 1170 } 1171 error = in_pcballoc(so, &tcbinfo, td); 1172 if (error) 1173 return (error); 1174 inp = sotoinpcb(so); 1175 #ifdef INET6 1176 if (isipv6) { 1177 inp->inp_vflag |= INP_IPV6; 1178 inp->in6p_hops = -1; /* use kernel default */ 1179 } 1180 else 1181 #endif 1182 inp->inp_vflag |= INP_IPV4; 1183 tp = tcp_newtcpcb(inp); 1184 if (tp == 0) { 1185 int nofd = so->so_state & SS_NOFDREF; /* XXX */ 1186 1187 so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */ 1188 #ifdef INET6 1189 if (isipv6) 1190 in6_pcbdetach(inp); 1191 else 1192 #endif 1193 in_pcbdetach(inp); 1194 so->so_state |= nofd; 1195 return (ENOBUFS); 1196 } 1197 tp->t_state = TCPS_CLOSED; 1198 return (0); 1199 } 1200 1201 /* 1202 * Initiate (or continue) disconnect. 1203 * If embryonic state, just send reset (once). 1204 * If in ``let data drain'' option and linger null, just drop. 1205 * Otherwise (hard), mark socket disconnecting and drop 1206 * current input data; switch states based on user close, and 1207 * send segment to peer (with FIN). 1208 */ 1209 static struct tcpcb * 1210 tcp_disconnect(tp) 1211 register struct tcpcb *tp; 1212 { 1213 struct socket *so = tp->t_inpcb->inp_socket; 1214 1215 if (tp->t_state < TCPS_ESTABLISHED) 1216 tp = tcp_close(tp); 1217 else if ((so->so_options & SO_LINGER) && so->so_linger == 0) 1218 tp = tcp_drop(tp, 0); 1219 else { 1220 soisdisconnecting(so); 1221 sbflush(&so->so_rcv); 1222 tp = tcp_usrclosed(tp); 1223 if (tp) 1224 (void) tcp_output(tp); 1225 } 1226 return (tp); 1227 } 1228 1229 /* 1230 * User issued close, and wish to trail through shutdown states: 1231 * if never received SYN, just forget it. If got a SYN from peer, 1232 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. 1233 * If already got a FIN from peer, then almost done; go to LAST_ACK 1234 * state. In all other cases, have already sent FIN to peer (e.g. 1235 * after PRU_SHUTDOWN), and just have to play tedious game waiting 1236 * for peer to send FIN or not respond to keep-alives, etc. 1237 * We can let the user exit from the close as soon as the FIN is acked. 1238 */ 1239 static struct tcpcb * 1240 tcp_usrclosed(tp) 1241 register struct tcpcb *tp; 1242 { 1243 1244 switch (tp->t_state) { 1245 1246 case TCPS_CLOSED: 1247 case TCPS_LISTEN: 1248 tp->t_state = TCPS_CLOSED; 1249 tp = tcp_close(tp); 1250 break; 1251 1252 case TCPS_SYN_SENT: 1253 case TCPS_SYN_RECEIVED: 1254 tp->t_flags |= TF_NEEDFIN; 1255 break; 1256 1257 case TCPS_ESTABLISHED: 1258 tp->t_state = TCPS_FIN_WAIT_1; 1259 break; 1260 1261 case TCPS_CLOSE_WAIT: 1262 tp->t_state = TCPS_LAST_ACK; 1263 break; 1264 } 1265 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) { 1266 soisdisconnected(tp->t_inpcb->inp_socket); 1267 /* To prevent the connection hanging in FIN_WAIT_2 forever. */ 1268 if (tp->t_state == TCPS_FIN_WAIT_2) 1269 callout_reset(tp->tt_2msl, tcp_maxidle, 1270 tcp_timer_2msl, tp); 1271 } 1272 return (tp); 1273 } 1274
Cache object: 078ec2491e8144d7773ca7038cc69a66
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