1 /* $NetBSD: uipc_socket.c,v 1.163 2008/04/29 17:35:31 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 2002, 2007, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of Wasabi Systems, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 2004 The FreeBSD Foundation 34 * Copyright (c) 2004 Robert Watson 35 * Copyright (c) 1982, 1986, 1988, 1990, 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. Neither the name of the University nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 * 62 * @(#)uipc_socket.c 8.6 (Berkeley) 5/2/95 63 */ 64 65 #include <sys/cdefs.h> 66 __KERNEL_RCSID(0, "$NetBSD: uipc_socket.c,v 1.163 2008/04/29 17:35:31 ad Exp $"); 67 68 #include "opt_sock_counters.h" 69 #include "opt_sosend_loan.h" 70 #include "opt_mbuftrace.h" 71 #include "opt_somaxkva.h" 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/proc.h> 76 #include <sys/file.h> 77 #include <sys/filedesc.h> 78 #include <sys/malloc.h> 79 #include <sys/mbuf.h> 80 #include <sys/domain.h> 81 #include <sys/kernel.h> 82 #include <sys/protosw.h> 83 #include <sys/socket.h> 84 #include <sys/socketvar.h> 85 #include <sys/signalvar.h> 86 #include <sys/resourcevar.h> 87 #include <sys/event.h> 88 #include <sys/poll.h> 89 #include <sys/kauth.h> 90 #include <sys/mutex.h> 91 #include <sys/condvar.h> 92 93 #include <uvm/uvm.h> 94 95 MALLOC_DEFINE(M_SOOPTS, "soopts", "socket options"); 96 MALLOC_DEFINE(M_SONAME, "soname", "socket name"); 97 98 extern const struct fileops socketops; 99 100 extern int somaxconn; /* patchable (XXX sysctl) */ 101 int somaxconn = SOMAXCONN; 102 kmutex_t *softnet_lock; 103 104 #ifdef SOSEND_COUNTERS 105 #include <sys/device.h> 106 107 static struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 108 NULL, "sosend", "loan big"); 109 static struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 110 NULL, "sosend", "copy big"); 111 static struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 112 NULL, "sosend", "copy small"); 113 static struct evcnt sosend_kvalimit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 114 NULL, "sosend", "kva limit"); 115 116 #define SOSEND_COUNTER_INCR(ev) (ev)->ev_count++ 117 118 EVCNT_ATTACH_STATIC(sosend_loan_big); 119 EVCNT_ATTACH_STATIC(sosend_copy_big); 120 EVCNT_ATTACH_STATIC(sosend_copy_small); 121 EVCNT_ATTACH_STATIC(sosend_kvalimit); 122 #else 123 124 #define SOSEND_COUNTER_INCR(ev) /* nothing */ 125 126 #endif /* SOSEND_COUNTERS */ 127 128 static struct callback_entry sokva_reclaimerentry; 129 130 #ifdef SOSEND_NO_LOAN 131 int sock_loan_thresh = -1; 132 #else 133 int sock_loan_thresh = 4096; 134 #endif 135 136 static kmutex_t so_pendfree_lock; 137 static struct mbuf *so_pendfree; 138 139 #ifndef SOMAXKVA 140 #define SOMAXKVA (16 * 1024 * 1024) 141 #endif 142 int somaxkva = SOMAXKVA; 143 static int socurkva; 144 static kcondvar_t socurkva_cv; 145 146 #define SOCK_LOAN_CHUNK 65536 147 148 static size_t sodopendfree(void); 149 static size_t sodopendfreel(void); 150 151 static vsize_t 152 sokvareserve(struct socket *so, vsize_t len) 153 { 154 int error; 155 156 mutex_enter(&so_pendfree_lock); 157 while (socurkva + len > somaxkva) { 158 size_t freed; 159 160 /* 161 * try to do pendfree. 162 */ 163 164 freed = sodopendfreel(); 165 166 /* 167 * if some kva was freed, try again. 168 */ 169 170 if (freed) 171 continue; 172 173 SOSEND_COUNTER_INCR(&sosend_kvalimit); 174 error = cv_wait_sig(&socurkva_cv, &so_pendfree_lock); 175 if (error) { 176 len = 0; 177 break; 178 } 179 } 180 socurkva += len; 181 mutex_exit(&so_pendfree_lock); 182 return len; 183 } 184 185 static void 186 sokvaunreserve(vsize_t len) 187 { 188 189 mutex_enter(&so_pendfree_lock); 190 socurkva -= len; 191 cv_broadcast(&socurkva_cv); 192 mutex_exit(&so_pendfree_lock); 193 } 194 195 /* 196 * sokvaalloc: allocate kva for loan. 197 */ 198 199 vaddr_t 200 sokvaalloc(vsize_t len, struct socket *so) 201 { 202 vaddr_t lva; 203 204 /* 205 * reserve kva. 206 */ 207 208 if (sokvareserve(so, len) == 0) 209 return 0; 210 211 /* 212 * allocate kva. 213 */ 214 215 lva = uvm_km_alloc(kernel_map, len, 0, UVM_KMF_VAONLY | UVM_KMF_WAITVA); 216 if (lva == 0) { 217 sokvaunreserve(len); 218 return (0); 219 } 220 221 return lva; 222 } 223 224 /* 225 * sokvafree: free kva for loan. 226 */ 227 228 void 229 sokvafree(vaddr_t sva, vsize_t len) 230 { 231 232 /* 233 * free kva. 234 */ 235 236 uvm_km_free(kernel_map, sva, len, UVM_KMF_VAONLY); 237 238 /* 239 * unreserve kva. 240 */ 241 242 sokvaunreserve(len); 243 } 244 245 static void 246 sodoloanfree(struct vm_page **pgs, void *buf, size_t size) 247 { 248 vaddr_t sva, eva; 249 vsize_t len; 250 int npgs; 251 252 KASSERT(pgs != NULL); 253 254 eva = round_page((vaddr_t) buf + size); 255 sva = trunc_page((vaddr_t) buf); 256 len = eva - sva; 257 npgs = len >> PAGE_SHIFT; 258 259 pmap_kremove(sva, len); 260 pmap_update(pmap_kernel()); 261 uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE); 262 sokvafree(sva, len); 263 } 264 265 static size_t 266 sodopendfree(void) 267 { 268 size_t rv; 269 270 if (__predict_true(so_pendfree == NULL)) 271 return 0; 272 273 mutex_enter(&so_pendfree_lock); 274 rv = sodopendfreel(); 275 mutex_exit(&so_pendfree_lock); 276 277 return rv; 278 } 279 280 /* 281 * sodopendfreel: free mbufs on "pendfree" list. 282 * unlock and relock so_pendfree_lock when freeing mbufs. 283 * 284 * => called with so_pendfree_lock held. 285 */ 286 287 static size_t 288 sodopendfreel(void) 289 { 290 struct mbuf *m, *next; 291 size_t rv = 0; 292 293 KASSERT(mutex_owned(&so_pendfree_lock)); 294 295 while (so_pendfree != NULL) { 296 m = so_pendfree; 297 so_pendfree = NULL; 298 mutex_exit(&so_pendfree_lock); 299 300 for (; m != NULL; m = next) { 301 next = m->m_next; 302 KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0); 303 KASSERT(m->m_ext.ext_refcnt == 0); 304 305 rv += m->m_ext.ext_size; 306 sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf, 307 m->m_ext.ext_size); 308 pool_cache_put(mb_cache, m); 309 } 310 311 mutex_enter(&so_pendfree_lock); 312 } 313 314 return (rv); 315 } 316 317 void 318 soloanfree(struct mbuf *m, void *buf, size_t size, void *arg) 319 { 320 321 KASSERT(m != NULL); 322 323 /* 324 * postpone freeing mbuf. 325 * 326 * we can't do it in interrupt context 327 * because we need to put kva back to kernel_map. 328 */ 329 330 mutex_enter(&so_pendfree_lock); 331 m->m_next = so_pendfree; 332 so_pendfree = m; 333 cv_broadcast(&socurkva_cv); 334 mutex_exit(&so_pendfree_lock); 335 } 336 337 static long 338 sosend_loan(struct socket *so, struct uio *uio, struct mbuf *m, long space) 339 { 340 struct iovec *iov = uio->uio_iov; 341 vaddr_t sva, eva; 342 vsize_t len; 343 vaddr_t lva; 344 int npgs, error; 345 vaddr_t va; 346 int i; 347 348 if (VMSPACE_IS_KERNEL_P(uio->uio_vmspace)) 349 return (0); 350 351 if (iov->iov_len < (size_t) space) 352 space = iov->iov_len; 353 if (space > SOCK_LOAN_CHUNK) 354 space = SOCK_LOAN_CHUNK; 355 356 eva = round_page((vaddr_t) iov->iov_base + space); 357 sva = trunc_page((vaddr_t) iov->iov_base); 358 len = eva - sva; 359 npgs = len >> PAGE_SHIFT; 360 361 KASSERT(npgs <= M_EXT_MAXPAGES); 362 363 lva = sokvaalloc(len, so); 364 if (lva == 0) 365 return 0; 366 367 error = uvm_loan(&uio->uio_vmspace->vm_map, sva, len, 368 m->m_ext.ext_pgs, UVM_LOAN_TOPAGE); 369 if (error) { 370 sokvafree(lva, len); 371 return (0); 372 } 373 374 for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE) 375 pmap_kenter_pa(va, VM_PAGE_TO_PHYS(m->m_ext.ext_pgs[i]), 376 VM_PROT_READ); 377 pmap_update(pmap_kernel()); 378 379 lva += (vaddr_t) iov->iov_base & PAGE_MASK; 380 381 MEXTADD(m, (void *) lva, space, M_MBUF, soloanfree, so); 382 m->m_flags |= M_EXT_PAGES | M_EXT_ROMAP; 383 384 uio->uio_resid -= space; 385 /* uio_offset not updated, not set/used for write(2) */ 386 uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + space; 387 uio->uio_iov->iov_len -= space; 388 if (uio->uio_iov->iov_len == 0) { 389 uio->uio_iov++; 390 uio->uio_iovcnt--; 391 } 392 393 return (space); 394 } 395 396 static int 397 sokva_reclaim_callback(struct callback_entry *ce, void *obj, void *arg) 398 { 399 400 KASSERT(ce == &sokva_reclaimerentry); 401 KASSERT(obj == NULL); 402 403 sodopendfree(); 404 if (!vm_map_starved_p(kernel_map)) { 405 return CALLBACK_CHAIN_ABORT; 406 } 407 return CALLBACK_CHAIN_CONTINUE; 408 } 409 410 struct mbuf * 411 getsombuf(struct socket *so, int type) 412 { 413 struct mbuf *m; 414 415 m = m_get(M_WAIT, type); 416 MCLAIM(m, so->so_mowner); 417 return m; 418 } 419 420 struct mbuf * 421 m_intopt(struct socket *so, int val) 422 { 423 struct mbuf *m; 424 425 m = getsombuf(so, MT_SOOPTS); 426 m->m_len = sizeof(int); 427 *mtod(m, int *) = val; 428 return m; 429 } 430 431 void 432 soinit(void) 433 { 434 435 mutex_init(&so_pendfree_lock, MUTEX_DEFAULT, IPL_VM); 436 softnet_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE); 437 cv_init(&socurkva_cv, "sokva"); 438 439 /* Set the initial adjusted socket buffer size. */ 440 if (sb_max_set(sb_max)) 441 panic("bad initial sb_max value: %lu", sb_max); 442 443 callback_register(&vm_map_to_kernel(kernel_map)->vmk_reclaim_callback, 444 &sokva_reclaimerentry, NULL, sokva_reclaim_callback); 445 } 446 447 /* 448 * Socket operation routines. 449 * These routines are called by the routines in 450 * sys_socket.c or from a system process, and 451 * implement the semantics of socket operations by 452 * switching out to the protocol specific routines. 453 */ 454 /*ARGSUSED*/ 455 int 456 socreate(int dom, struct socket **aso, int type, int proto, struct lwp *l, 457 struct socket *lockso) 458 { 459 const struct protosw *prp; 460 struct socket *so; 461 uid_t uid; 462 int error; 463 kmutex_t *lock; 464 465 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET, 466 KAUTH_REQ_NETWORK_SOCKET_OPEN, KAUTH_ARG(dom), KAUTH_ARG(type), 467 KAUTH_ARG(proto)); 468 if (error != 0) 469 return error; 470 471 if (proto) 472 prp = pffindproto(dom, proto, type); 473 else 474 prp = pffindtype(dom, type); 475 if (prp == NULL) { 476 /* no support for domain */ 477 if (pffinddomain(dom) == 0) 478 return EAFNOSUPPORT; 479 /* no support for socket type */ 480 if (proto == 0 && type != 0) 481 return EPROTOTYPE; 482 return EPROTONOSUPPORT; 483 } 484 if (prp->pr_usrreq == NULL) 485 return EPROTONOSUPPORT; 486 if (prp->pr_type != type) 487 return EPROTOTYPE; 488 489 so = soget(true); 490 so->so_type = type; 491 so->so_proto = prp; 492 so->so_send = sosend; 493 so->so_receive = soreceive; 494 #ifdef MBUFTRACE 495 so->so_rcv.sb_mowner = &prp->pr_domain->dom_mowner; 496 so->so_snd.sb_mowner = &prp->pr_domain->dom_mowner; 497 so->so_mowner = &prp->pr_domain->dom_mowner; 498 #endif 499 uid = kauth_cred_geteuid(l->l_cred); 500 so->so_uidinfo = uid_find(uid); 501 if (lockso != NULL) { 502 /* Caller wants us to share a lock. */ 503 lock = lockso->so_lock; 504 so->so_lock = lock; 505 mutex_obj_hold(lock); 506 mutex_enter(lock); 507 } else { 508 /* Lock assigned and taken during PRU_ATTACH. */ 509 } 510 error = (*prp->pr_usrreq)(so, PRU_ATTACH, NULL, 511 (struct mbuf *)(long)proto, NULL, l); 512 KASSERT(solocked(so)); 513 if (error != 0) { 514 so->so_state |= SS_NOFDREF; 515 sofree(so); 516 return error; 517 } 518 sounlock(so); 519 *aso = so; 520 return 0; 521 } 522 523 /* On success, write file descriptor to fdout and return zero. On 524 * failure, return non-zero; *fdout will be undefined. 525 */ 526 int 527 fsocreate(int domain, struct socket **sop, int type, int protocol, 528 struct lwp *l, int *fdout) 529 { 530 struct socket *so; 531 struct file *fp; 532 int fd, error; 533 534 if ((error = fd_allocfile(&fp, &fd)) != 0) 535 return (error); 536 fp->f_flag = FREAD|FWRITE; 537 fp->f_type = DTYPE_SOCKET; 538 fp->f_ops = &socketops; 539 error = socreate(domain, &so, type, protocol, l, NULL); 540 if (error != 0) { 541 fd_abort(curproc, fp, fd); 542 } else { 543 if (sop != NULL) 544 *sop = so; 545 fp->f_data = so; 546 fd_affix(curproc, fp, fd); 547 *fdout = fd; 548 } 549 return error; 550 } 551 552 int 553 sobind(struct socket *so, struct mbuf *nam, struct lwp *l) 554 { 555 int error; 556 557 solock(so); 558 error = (*so->so_proto->pr_usrreq)(so, PRU_BIND, NULL, nam, NULL, l); 559 sounlock(so); 560 return error; 561 } 562 563 int 564 solisten(struct socket *so, int backlog, struct lwp *l) 565 { 566 int error; 567 568 solock(so); 569 if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING | 570 SS_ISDISCONNECTING)) != 0) { 571 sounlock(so); 572 return (EOPNOTSUPP); 573 } 574 error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, NULL, 575 NULL, NULL, l); 576 if (error != 0) { 577 sounlock(so); 578 return error; 579 } 580 if (TAILQ_EMPTY(&so->so_q)) 581 so->so_options |= SO_ACCEPTCONN; 582 if (backlog < 0) 583 backlog = 0; 584 so->so_qlimit = min(backlog, somaxconn); 585 sounlock(so); 586 return 0; 587 } 588 589 void 590 sofree(struct socket *so) 591 { 592 u_int refs; 593 594 KASSERT(solocked(so)); 595 596 if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) { 597 sounlock(so); 598 return; 599 } 600 if (so->so_head) { 601 /* 602 * We must not decommission a socket that's on the accept(2) 603 * queue. If we do, then accept(2) may hang after select(2) 604 * indicated that the listening socket was ready. 605 */ 606 if (!soqremque(so, 0)) { 607 sounlock(so); 608 return; 609 } 610 } 611 if (so->so_rcv.sb_hiwat) 612 (void)chgsbsize(so->so_uidinfo, &so->so_rcv.sb_hiwat, 0, 613 RLIM_INFINITY); 614 if (so->so_snd.sb_hiwat) 615 (void)chgsbsize(so->so_uidinfo, &so->so_snd.sb_hiwat, 0, 616 RLIM_INFINITY); 617 sbrelease(&so->so_snd, so); 618 KASSERT(!cv_has_waiters(&so->so_cv)); 619 KASSERT(!cv_has_waiters(&so->so_rcv.sb_cv)); 620 KASSERT(!cv_has_waiters(&so->so_snd.sb_cv)); 621 sorflush(so); 622 refs = so->so_aborting; /* XXX */ 623 sounlock(so); 624 if (refs == 0) /* XXX */ 625 soput(so); 626 } 627 628 /* 629 * Close a socket on last file table reference removal. 630 * Initiate disconnect if connected. 631 * Free socket when disconnect complete. 632 */ 633 int 634 soclose(struct socket *so) 635 { 636 struct socket *so2; 637 int error; 638 int error2; 639 640 error = 0; 641 solock(so); 642 if (so->so_options & SO_ACCEPTCONN) { 643 do { 644 if ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) { 645 KASSERT(solocked2(so, so2)); 646 (void) soqremque(so2, 0); 647 /* soabort drops the lock. */ 648 (void) soabort(so2); 649 solock(so); 650 continue; 651 } 652 if ((so2 = TAILQ_FIRST(&so->so_q)) != 0) { 653 KASSERT(solocked2(so, so2)); 654 (void) soqremque(so2, 1); 655 /* soabort drops the lock. */ 656 (void) soabort(so2); 657 solock(so); 658 continue; 659 } 660 } while (0); 661 } 662 if (so->so_pcb == 0) 663 goto discard; 664 if (so->so_state & SS_ISCONNECTED) { 665 if ((so->so_state & SS_ISDISCONNECTING) == 0) { 666 error = sodisconnect(so); 667 if (error) 668 goto drop; 669 } 670 if (so->so_options & SO_LINGER) { 671 if ((so->so_state & SS_ISDISCONNECTING) && so->so_nbio) 672 goto drop; 673 while (so->so_state & SS_ISCONNECTED) { 674 error = sowait(so, so->so_linger * hz); 675 if (error) 676 break; 677 } 678 } 679 } 680 drop: 681 if (so->so_pcb) { 682 error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH, 683 NULL, NULL, NULL, NULL); 684 if (error == 0) 685 error = error2; 686 } 687 discard: 688 if (so->so_state & SS_NOFDREF) 689 panic("soclose: NOFDREF"); 690 so->so_state |= SS_NOFDREF; 691 sofree(so); 692 return (error); 693 } 694 695 /* 696 * Must be called with the socket locked.. Will return with it unlocked. 697 */ 698 int 699 soabort(struct socket *so) 700 { 701 u_int refs; 702 int error; 703 704 KASSERT(solocked(so)); 705 KASSERT(so->so_head == NULL); 706 707 so->so_aborting++; /* XXX */ 708 error = (*so->so_proto->pr_usrreq)(so, PRU_ABORT, NULL, 709 NULL, NULL, NULL); 710 refs = --so->so_aborting; /* XXX */ 711 if (error) { 712 sofree(so); 713 } else { 714 sounlock(so); 715 if (refs == 0) 716 sofree(so); 717 } 718 return error; 719 } 720 721 int 722 soaccept(struct socket *so, struct mbuf *nam) 723 { 724 int error; 725 726 KASSERT(solocked(so)); 727 728 error = 0; 729 if ((so->so_state & SS_NOFDREF) == 0) 730 panic("soaccept: !NOFDREF"); 731 so->so_state &= ~SS_NOFDREF; 732 if ((so->so_state & SS_ISDISCONNECTED) == 0 || 733 (so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0) 734 error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT, 735 NULL, nam, NULL, NULL); 736 else 737 error = ECONNABORTED; 738 739 return (error); 740 } 741 742 int 743 soconnect(struct socket *so, struct mbuf *nam, struct lwp *l) 744 { 745 int error; 746 747 KASSERT(solocked(so)); 748 749 if (so->so_options & SO_ACCEPTCONN) 750 return (EOPNOTSUPP); 751 /* 752 * If protocol is connection-based, can only connect once. 753 * Otherwise, if connected, try to disconnect first. 754 * This allows user to disconnect by connecting to, e.g., 755 * a null address. 756 */ 757 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && 758 ((so->so_proto->pr_flags & PR_CONNREQUIRED) || 759 (error = sodisconnect(so)))) 760 error = EISCONN; 761 else 762 error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT, 763 NULL, nam, NULL, l); 764 return (error); 765 } 766 767 int 768 soconnect2(struct socket *so1, struct socket *so2) 769 { 770 int error; 771 772 KASSERT(solocked2(so1, so2)); 773 774 error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2, 775 NULL, (struct mbuf *)so2, NULL, NULL); 776 return (error); 777 } 778 779 int 780 sodisconnect(struct socket *so) 781 { 782 int error; 783 784 KASSERT(solocked(so)); 785 786 if ((so->so_state & SS_ISCONNECTED) == 0) { 787 error = ENOTCONN; 788 } else if (so->so_state & SS_ISDISCONNECTING) { 789 error = EALREADY; 790 } else { 791 error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, 792 NULL, NULL, NULL, NULL); 793 } 794 sodopendfree(); 795 return (error); 796 } 797 798 #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK) 799 /* 800 * Send on a socket. 801 * If send must go all at once and message is larger than 802 * send buffering, then hard error. 803 * Lock against other senders. 804 * If must go all at once and not enough room now, then 805 * inform user that this would block and do nothing. 806 * Otherwise, if nonblocking, send as much as possible. 807 * The data to be sent is described by "uio" if nonzero, 808 * otherwise by the mbuf chain "top" (which must be null 809 * if uio is not). Data provided in mbuf chain must be small 810 * enough to send all at once. 811 * 812 * Returns nonzero on error, timeout or signal; callers 813 * must check for short counts if EINTR/ERESTART are returned. 814 * Data and control buffers are freed on return. 815 */ 816 int 817 sosend(struct socket *so, struct mbuf *addr, struct uio *uio, struct mbuf *top, 818 struct mbuf *control, int flags, struct lwp *l) 819 { 820 struct mbuf **mp, *m; 821 struct proc *p; 822 long space, len, resid, clen, mlen; 823 int error, s, dontroute, atomic; 824 825 p = l->l_proc; 826 sodopendfree(); 827 clen = 0; 828 829 /* 830 * solock() provides atomicity of access. splsoftnet() prevents 831 * protocol processing soft interrupts from interrupting us and 832 * blocking (expensive). 833 */ 834 s = splsoftnet(); 835 solock(so); 836 atomic = sosendallatonce(so) || top; 837 if (uio) 838 resid = uio->uio_resid; 839 else 840 resid = top->m_pkthdr.len; 841 /* 842 * In theory resid should be unsigned. 843 * However, space must be signed, as it might be less than 0 844 * if we over-committed, and we must use a signed comparison 845 * of space and resid. On the other hand, a negative resid 846 * causes us to loop sending 0-length segments to the protocol. 847 */ 848 if (resid < 0) { 849 error = EINVAL; 850 goto out; 851 } 852 dontroute = 853 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && 854 (so->so_proto->pr_flags & PR_ATOMIC); 855 if (l) 856 l->l_ru.ru_msgsnd++; 857 if (control) 858 clen = control->m_len; 859 restart: 860 if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0) 861 goto out; 862 do { 863 if (so->so_state & SS_CANTSENDMORE) { 864 error = EPIPE; 865 goto release; 866 } 867 if (so->so_error) { 868 error = so->so_error; 869 so->so_error = 0; 870 goto release; 871 } 872 if ((so->so_state & SS_ISCONNECTED) == 0) { 873 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 874 if ((so->so_state & SS_ISCONFIRMING) == 0 && 875 !(resid == 0 && clen != 0)) { 876 error = ENOTCONN; 877 goto release; 878 } 879 } else if (addr == 0) { 880 error = EDESTADDRREQ; 881 goto release; 882 } 883 } 884 space = sbspace(&so->so_snd); 885 if (flags & MSG_OOB) 886 space += 1024; 887 if ((atomic && resid > so->so_snd.sb_hiwat) || 888 clen > so->so_snd.sb_hiwat) { 889 error = EMSGSIZE; 890 goto release; 891 } 892 if (space < resid + clen && 893 (atomic || space < so->so_snd.sb_lowat || space < clen)) { 894 if (so->so_nbio) { 895 error = EWOULDBLOCK; 896 goto release; 897 } 898 sbunlock(&so->so_snd); 899 error = sbwait(&so->so_snd); 900 if (error) 901 goto out; 902 goto restart; 903 } 904 mp = ⊤ 905 space -= clen; 906 do { 907 if (uio == NULL) { 908 /* 909 * Data is prepackaged in "top". 910 */ 911 resid = 0; 912 if (flags & MSG_EOR) 913 top->m_flags |= M_EOR; 914 } else do { 915 sounlock(so); 916 splx(s); 917 if (top == NULL) { 918 m = m_gethdr(M_WAIT, MT_DATA); 919 mlen = MHLEN; 920 m->m_pkthdr.len = 0; 921 m->m_pkthdr.rcvif = NULL; 922 } else { 923 m = m_get(M_WAIT, MT_DATA); 924 mlen = MLEN; 925 } 926 MCLAIM(m, so->so_snd.sb_mowner); 927 if (sock_loan_thresh >= 0 && 928 uio->uio_iov->iov_len >= sock_loan_thresh && 929 space >= sock_loan_thresh && 930 (len = sosend_loan(so, uio, m, 931 space)) != 0) { 932 SOSEND_COUNTER_INCR(&sosend_loan_big); 933 space -= len; 934 goto have_data; 935 } 936 if (resid >= MINCLSIZE && space >= MCLBYTES) { 937 SOSEND_COUNTER_INCR(&sosend_copy_big); 938 m_clget(m, M_WAIT); 939 if ((m->m_flags & M_EXT) == 0) 940 goto nopages; 941 mlen = MCLBYTES; 942 if (atomic && top == 0) { 943 len = lmin(MCLBYTES - max_hdr, 944 resid); 945 m->m_data += max_hdr; 946 } else 947 len = lmin(MCLBYTES, resid); 948 space -= len; 949 } else { 950 nopages: 951 SOSEND_COUNTER_INCR(&sosend_copy_small); 952 len = lmin(lmin(mlen, resid), space); 953 space -= len; 954 /* 955 * For datagram protocols, leave room 956 * for protocol headers in first mbuf. 957 */ 958 if (atomic && top == 0 && len < mlen) 959 MH_ALIGN(m, len); 960 } 961 error = uiomove(mtod(m, void *), (int)len, uio); 962 have_data: 963 resid = uio->uio_resid; 964 m->m_len = len; 965 *mp = m; 966 top->m_pkthdr.len += len; 967 s = splsoftnet(); 968 solock(so); 969 if (error != 0) 970 goto release; 971 mp = &m->m_next; 972 if (resid <= 0) { 973 if (flags & MSG_EOR) 974 top->m_flags |= M_EOR; 975 break; 976 } 977 } while (space > 0 && atomic); 978 979 if (so->so_state & SS_CANTSENDMORE) { 980 error = EPIPE; 981 goto release; 982 } 983 if (dontroute) 984 so->so_options |= SO_DONTROUTE; 985 if (resid > 0) 986 so->so_state |= SS_MORETOCOME; 987 error = (*so->so_proto->pr_usrreq)(so, 988 (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND, 989 top, addr, control, curlwp); 990 if (dontroute) 991 so->so_options &= ~SO_DONTROUTE; 992 if (resid > 0) 993 so->so_state &= ~SS_MORETOCOME; 994 clen = 0; 995 control = NULL; 996 top = NULL; 997 mp = ⊤ 998 if (error != 0) 999 goto release; 1000 } while (resid && space > 0); 1001 } while (resid); 1002 1003 release: 1004 sbunlock(&so->so_snd); 1005 out: 1006 sounlock(so); 1007 splx(s); 1008 if (top) 1009 m_freem(top); 1010 if (control) 1011 m_freem(control); 1012 return (error); 1013 } 1014 1015 /* 1016 * Following replacement or removal of the first mbuf on the first 1017 * mbuf chain of a socket buffer, push necessary state changes back 1018 * into the socket buffer so that other consumers see the values 1019 * consistently. 'nextrecord' is the callers locally stored value of 1020 * the original value of sb->sb_mb->m_nextpkt which must be restored 1021 * when the lead mbuf changes. NOTE: 'nextrecord' may be NULL. 1022 */ 1023 static void 1024 sbsync(struct sockbuf *sb, struct mbuf *nextrecord) 1025 { 1026 1027 KASSERT(solocked(sb->sb_so)); 1028 1029 /* 1030 * First, update for the new value of nextrecord. If necessary, 1031 * make it the first record. 1032 */ 1033 if (sb->sb_mb != NULL) 1034 sb->sb_mb->m_nextpkt = nextrecord; 1035 else 1036 sb->sb_mb = nextrecord; 1037 1038 /* 1039 * Now update any dependent socket buffer fields to reflect 1040 * the new state. This is an inline of SB_EMPTY_FIXUP, with 1041 * the addition of a second clause that takes care of the 1042 * case where sb_mb has been updated, but remains the last 1043 * record. 1044 */ 1045 if (sb->sb_mb == NULL) { 1046 sb->sb_mbtail = NULL; 1047 sb->sb_lastrecord = NULL; 1048 } else if (sb->sb_mb->m_nextpkt == NULL) 1049 sb->sb_lastrecord = sb->sb_mb; 1050 } 1051 1052 /* 1053 * Implement receive operations on a socket. 1054 * We depend on the way that records are added to the sockbuf 1055 * by sbappend*. In particular, each record (mbufs linked through m_next) 1056 * must begin with an address if the protocol so specifies, 1057 * followed by an optional mbuf or mbufs containing ancillary data, 1058 * and then zero or more mbufs of data. 1059 * In order to avoid blocking network interrupts for the entire time here, 1060 * we splx() while doing the actual copy to user space. 1061 * Although the sockbuf is locked, new data may still be appended, 1062 * and thus we must maintain consistency of the sockbuf during that time. 1063 * 1064 * The caller may receive the data as a single mbuf chain by supplying 1065 * an mbuf **mp0 for use in returning the chain. The uio is then used 1066 * only for the count in uio_resid. 1067 */ 1068 int 1069 soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio, 1070 struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 1071 { 1072 struct lwp *l = curlwp; 1073 struct mbuf *m, **mp, *mt; 1074 int atomic, flags, len, error, s, offset, moff, type, orig_resid; 1075 const struct protosw *pr; 1076 struct mbuf *nextrecord; 1077 int mbuf_removed = 0; 1078 const struct domain *dom; 1079 1080 pr = so->so_proto; 1081 atomic = pr->pr_flags & PR_ATOMIC; 1082 dom = pr->pr_domain; 1083 mp = mp0; 1084 type = 0; 1085 orig_resid = uio->uio_resid; 1086 1087 if (paddr != NULL) 1088 *paddr = NULL; 1089 if (controlp != NULL) 1090 *controlp = NULL; 1091 if (flagsp != NULL) 1092 flags = *flagsp &~ MSG_EOR; 1093 else 1094 flags = 0; 1095 1096 if ((flags & MSG_DONTWAIT) == 0) 1097 sodopendfree(); 1098 1099 if (flags & MSG_OOB) { 1100 m = m_get(M_WAIT, MT_DATA); 1101 solock(so); 1102 error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m, 1103 (struct mbuf *)(long)(flags & MSG_PEEK), NULL, l); 1104 sounlock(so); 1105 if (error) 1106 goto bad; 1107 do { 1108 error = uiomove(mtod(m, void *), 1109 (int) min(uio->uio_resid, m->m_len), uio); 1110 m = m_free(m); 1111 } while (uio->uio_resid > 0 && error == 0 && m); 1112 bad: 1113 if (m != NULL) 1114 m_freem(m); 1115 return error; 1116 } 1117 if (mp != NULL) 1118 *mp = NULL; 1119 1120 /* 1121 * solock() provides atomicity of access. splsoftnet() prevents 1122 * protocol processing soft interrupts from interrupting us and 1123 * blocking (expensive). 1124 */ 1125 s = splsoftnet(); 1126 solock(so); 1127 if (so->so_state & SS_ISCONFIRMING && uio->uio_resid) 1128 (*pr->pr_usrreq)(so, PRU_RCVD, NULL, NULL, NULL, l); 1129 1130 restart: 1131 if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) { 1132 sounlock(so); 1133 splx(s); 1134 return error; 1135 } 1136 1137 m = so->so_rcv.sb_mb; 1138 /* 1139 * If we have less data than requested, block awaiting more 1140 * (subject to any timeout) if: 1141 * 1. the current count is less than the low water mark, 1142 * 2. MSG_WAITALL is set, and it is possible to do the entire 1143 * receive operation at once if we block (resid <= hiwat), or 1144 * 3. MSG_DONTWAIT is not set. 1145 * If MSG_WAITALL is set but resid is larger than the receive buffer, 1146 * we have to do the receive in sections, and thus risk returning 1147 * a short count if a timeout or signal occurs after we start. 1148 */ 1149 if (m == NULL || 1150 ((flags & MSG_DONTWAIT) == 0 && 1151 so->so_rcv.sb_cc < uio->uio_resid && 1152 (so->so_rcv.sb_cc < so->so_rcv.sb_lowat || 1153 ((flags & MSG_WAITALL) && 1154 uio->uio_resid <= so->so_rcv.sb_hiwat)) && 1155 m->m_nextpkt == NULL && !atomic)) { 1156 #ifdef DIAGNOSTIC 1157 if (m == NULL && so->so_rcv.sb_cc) 1158 panic("receive 1"); 1159 #endif 1160 if (so->so_error) { 1161 if (m != NULL) 1162 goto dontblock; 1163 error = so->so_error; 1164 if ((flags & MSG_PEEK) == 0) 1165 so->so_error = 0; 1166 goto release; 1167 } 1168 if (so->so_state & SS_CANTRCVMORE) { 1169 if (m != NULL) 1170 goto dontblock; 1171 else 1172 goto release; 1173 } 1174 for (; m != NULL; m = m->m_next) 1175 if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { 1176 m = so->so_rcv.sb_mb; 1177 goto dontblock; 1178 } 1179 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 && 1180 (so->so_proto->pr_flags & PR_CONNREQUIRED)) { 1181 error = ENOTCONN; 1182 goto release; 1183 } 1184 if (uio->uio_resid == 0) 1185 goto release; 1186 if (so->so_nbio || (flags & MSG_DONTWAIT)) { 1187 error = EWOULDBLOCK; 1188 goto release; 1189 } 1190 SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1"); 1191 SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1"); 1192 sbunlock(&so->so_rcv); 1193 error = sbwait(&so->so_rcv); 1194 if (error != 0) { 1195 sounlock(so); 1196 splx(s); 1197 return error; 1198 } 1199 goto restart; 1200 } 1201 dontblock: 1202 /* 1203 * On entry here, m points to the first record of the socket buffer. 1204 * From this point onward, we maintain 'nextrecord' as a cache of the 1205 * pointer to the next record in the socket buffer. We must keep the 1206 * various socket buffer pointers and local stack versions of the 1207 * pointers in sync, pushing out modifications before dropping the 1208 * socket lock, and re-reading them when picking it up. 1209 * 1210 * Otherwise, we will race with the network stack appending new data 1211 * or records onto the socket buffer by using inconsistent/stale 1212 * versions of the field, possibly resulting in socket buffer 1213 * corruption. 1214 * 1215 * By holding the high-level sblock(), we prevent simultaneous 1216 * readers from pulling off the front of the socket buffer. 1217 */ 1218 if (l != NULL) 1219 l->l_ru.ru_msgrcv++; 1220 KASSERT(m == so->so_rcv.sb_mb); 1221 SBLASTRECORDCHK(&so->so_rcv, "soreceive 1"); 1222 SBLASTMBUFCHK(&so->so_rcv, "soreceive 1"); 1223 nextrecord = m->m_nextpkt; 1224 if (pr->pr_flags & PR_ADDR) { 1225 #ifdef DIAGNOSTIC 1226 if (m->m_type != MT_SONAME) 1227 panic("receive 1a"); 1228 #endif 1229 orig_resid = 0; 1230 if (flags & MSG_PEEK) { 1231 if (paddr) 1232 *paddr = m_copy(m, 0, m->m_len); 1233 m = m->m_next; 1234 } else { 1235 sbfree(&so->so_rcv, m); 1236 mbuf_removed = 1; 1237 if (paddr != NULL) { 1238 *paddr = m; 1239 so->so_rcv.sb_mb = m->m_next; 1240 m->m_next = NULL; 1241 m = so->so_rcv.sb_mb; 1242 } else { 1243 MFREE(m, so->so_rcv.sb_mb); 1244 m = so->so_rcv.sb_mb; 1245 } 1246 sbsync(&so->so_rcv, nextrecord); 1247 } 1248 } 1249 1250 /* 1251 * Process one or more MT_CONTROL mbufs present before any data mbufs 1252 * in the first mbuf chain on the socket buffer. If MSG_PEEK, we 1253 * just copy the data; if !MSG_PEEK, we call into the protocol to 1254 * perform externalization (or freeing if controlp == NULL). 1255 */ 1256 if (__predict_false(m != NULL && m->m_type == MT_CONTROL)) { 1257 struct mbuf *cm = NULL, *cmn; 1258 struct mbuf **cme = &cm; 1259 1260 do { 1261 if (flags & MSG_PEEK) { 1262 if (controlp != NULL) { 1263 *controlp = m_copy(m, 0, m->m_len); 1264 controlp = &(*controlp)->m_next; 1265 } 1266 m = m->m_next; 1267 } else { 1268 sbfree(&so->so_rcv, m); 1269 so->so_rcv.sb_mb = m->m_next; 1270 m->m_next = NULL; 1271 *cme = m; 1272 cme = &(*cme)->m_next; 1273 m = so->so_rcv.sb_mb; 1274 } 1275 } while (m != NULL && m->m_type == MT_CONTROL); 1276 if ((flags & MSG_PEEK) == 0) 1277 sbsync(&so->so_rcv, nextrecord); 1278 for (; cm != NULL; cm = cmn) { 1279 cmn = cm->m_next; 1280 cm->m_next = NULL; 1281 type = mtod(cm, struct cmsghdr *)->cmsg_type; 1282 if (controlp != NULL) { 1283 if (dom->dom_externalize != NULL && 1284 type == SCM_RIGHTS) { 1285 sounlock(so); 1286 splx(s); 1287 error = (*dom->dom_externalize)(cm, l); 1288 s = splsoftnet(); 1289 solock(so); 1290 } 1291 *controlp = cm; 1292 while (*controlp != NULL) 1293 controlp = &(*controlp)->m_next; 1294 } else { 1295 /* 1296 * Dispose of any SCM_RIGHTS message that went 1297 * through the read path rather than recv. 1298 */ 1299 if (dom->dom_dispose != NULL && 1300 type == SCM_RIGHTS) { 1301 sounlock(so); 1302 (*dom->dom_dispose)(cm); 1303 solock(so); 1304 } 1305 m_freem(cm); 1306 } 1307 } 1308 if (m != NULL) 1309 nextrecord = so->so_rcv.sb_mb->m_nextpkt; 1310 else 1311 nextrecord = so->so_rcv.sb_mb; 1312 orig_resid = 0; 1313 } 1314 1315 /* If m is non-NULL, we have some data to read. */ 1316 if (__predict_true(m != NULL)) { 1317 type = m->m_type; 1318 if (type == MT_OOBDATA) 1319 flags |= MSG_OOB; 1320 } 1321 SBLASTRECORDCHK(&so->so_rcv, "soreceive 2"); 1322 SBLASTMBUFCHK(&so->so_rcv, "soreceive 2"); 1323 1324 moff = 0; 1325 offset = 0; 1326 while (m != NULL && uio->uio_resid > 0 && error == 0) { 1327 if (m->m_type == MT_OOBDATA) { 1328 if (type != MT_OOBDATA) 1329 break; 1330 } else if (type == MT_OOBDATA) 1331 break; 1332 #ifdef DIAGNOSTIC 1333 else if (m->m_type != MT_DATA && m->m_type != MT_HEADER) 1334 panic("receive 3"); 1335 #endif 1336 so->so_state &= ~SS_RCVATMARK; 1337 len = uio->uio_resid; 1338 if (so->so_oobmark && len > so->so_oobmark - offset) 1339 len = so->so_oobmark - offset; 1340 if (len > m->m_len - moff) 1341 len = m->m_len - moff; 1342 /* 1343 * If mp is set, just pass back the mbufs. 1344 * Otherwise copy them out via the uio, then free. 1345 * Sockbuf must be consistent here (points to current mbuf, 1346 * it points to next record) when we drop priority; 1347 * we must note any additions to the sockbuf when we 1348 * block interrupts again. 1349 */ 1350 if (mp == NULL) { 1351 SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove"); 1352 SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove"); 1353 sounlock(so); 1354 splx(s); 1355 error = uiomove(mtod(m, char *) + moff, (int)len, uio); 1356 s = splsoftnet(); 1357 solock(so); 1358 if (error != 0) { 1359 /* 1360 * If any part of the record has been removed 1361 * (such as the MT_SONAME mbuf, which will 1362 * happen when PR_ADDR, and thus also 1363 * PR_ATOMIC, is set), then drop the entire 1364 * record to maintain the atomicity of the 1365 * receive operation. 1366 * 1367 * This avoids a later panic("receive 1a") 1368 * when compiled with DIAGNOSTIC. 1369 */ 1370 if (m && mbuf_removed && atomic) 1371 (void) sbdroprecord(&so->so_rcv); 1372 1373 goto release; 1374 } 1375 } else 1376 uio->uio_resid -= len; 1377 if (len == m->m_len - moff) { 1378 if (m->m_flags & M_EOR) 1379 flags |= MSG_EOR; 1380 if (flags & MSG_PEEK) { 1381 m = m->m_next; 1382 moff = 0; 1383 } else { 1384 nextrecord = m->m_nextpkt; 1385 sbfree(&so->so_rcv, m); 1386 if (mp) { 1387 *mp = m; 1388 mp = &m->m_next; 1389 so->so_rcv.sb_mb = m = m->m_next; 1390 *mp = NULL; 1391 } else { 1392 MFREE(m, so->so_rcv.sb_mb); 1393 m = so->so_rcv.sb_mb; 1394 } 1395 /* 1396 * If m != NULL, we also know that 1397 * so->so_rcv.sb_mb != NULL. 1398 */ 1399 KASSERT(so->so_rcv.sb_mb == m); 1400 if (m) { 1401 m->m_nextpkt = nextrecord; 1402 if (nextrecord == NULL) 1403 so->so_rcv.sb_lastrecord = m; 1404 } else { 1405 so->so_rcv.sb_mb = nextrecord; 1406 SB_EMPTY_FIXUP(&so->so_rcv); 1407 } 1408 SBLASTRECORDCHK(&so->so_rcv, "soreceive 3"); 1409 SBLASTMBUFCHK(&so->so_rcv, "soreceive 3"); 1410 } 1411 } else if (flags & MSG_PEEK) 1412 moff += len; 1413 else { 1414 if (mp != NULL) { 1415 mt = m_copym(m, 0, len, M_NOWAIT); 1416 if (__predict_false(mt == NULL)) { 1417 sounlock(so); 1418 mt = m_copym(m, 0, len, M_WAIT); 1419 solock(so); 1420 } 1421 *mp = mt; 1422 } 1423 m->m_data += len; 1424 m->m_len -= len; 1425 so->so_rcv.sb_cc -= len; 1426 } 1427 if (so->so_oobmark) { 1428 if ((flags & MSG_PEEK) == 0) { 1429 so->so_oobmark -= len; 1430 if (so->so_oobmark == 0) { 1431 so->so_state |= SS_RCVATMARK; 1432 break; 1433 } 1434 } else { 1435 offset += len; 1436 if (offset == so->so_oobmark) 1437 break; 1438 } 1439 } 1440 if (flags & MSG_EOR) 1441 break; 1442 /* 1443 * If the MSG_WAITALL flag is set (for non-atomic socket), 1444 * we must not quit until "uio->uio_resid == 0" or an error 1445 * termination. If a signal/timeout occurs, return 1446 * with a short count but without error. 1447 * Keep sockbuf locked against other readers. 1448 */ 1449 while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && 1450 !sosendallatonce(so) && !nextrecord) { 1451 if (so->so_error || so->so_state & SS_CANTRCVMORE) 1452 break; 1453 /* 1454 * If we are peeking and the socket receive buffer is 1455 * full, stop since we can't get more data to peek at. 1456 */ 1457 if ((flags & MSG_PEEK) && sbspace(&so->so_rcv) <= 0) 1458 break; 1459 /* 1460 * If we've drained the socket buffer, tell the 1461 * protocol in case it needs to do something to 1462 * get it filled again. 1463 */ 1464 if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb) 1465 (*pr->pr_usrreq)(so, PRU_RCVD, 1466 NULL, (struct mbuf *)(long)flags, NULL, l); 1467 SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2"); 1468 SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2"); 1469 error = sbwait(&so->so_rcv); 1470 if (error != 0) { 1471 sbunlock(&so->so_rcv); 1472 sounlock(so); 1473 splx(s); 1474 return 0; 1475 } 1476 if ((m = so->so_rcv.sb_mb) != NULL) 1477 nextrecord = m->m_nextpkt; 1478 } 1479 } 1480 1481 if (m && atomic) { 1482 flags |= MSG_TRUNC; 1483 if ((flags & MSG_PEEK) == 0) 1484 (void) sbdroprecord(&so->so_rcv); 1485 } 1486 if ((flags & MSG_PEEK) == 0) { 1487 if (m == NULL) { 1488 /* 1489 * First part is an inline SB_EMPTY_FIXUP(). Second 1490 * part makes sure sb_lastrecord is up-to-date if 1491 * there is still data in the socket buffer. 1492 */ 1493 so->so_rcv.sb_mb = nextrecord; 1494 if (so->so_rcv.sb_mb == NULL) { 1495 so->so_rcv.sb_mbtail = NULL; 1496 so->so_rcv.sb_lastrecord = NULL; 1497 } else if (nextrecord->m_nextpkt == NULL) 1498 so->so_rcv.sb_lastrecord = nextrecord; 1499 } 1500 SBLASTRECORDCHK(&so->so_rcv, "soreceive 4"); 1501 SBLASTMBUFCHK(&so->so_rcv, "soreceive 4"); 1502 if (pr->pr_flags & PR_WANTRCVD && so->so_pcb) 1503 (*pr->pr_usrreq)(so, PRU_RCVD, NULL, 1504 (struct mbuf *)(long)flags, NULL, l); 1505 } 1506 if (orig_resid == uio->uio_resid && orig_resid && 1507 (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) { 1508 sbunlock(&so->so_rcv); 1509 goto restart; 1510 } 1511 1512 if (flagsp != NULL) 1513 *flagsp |= flags; 1514 release: 1515 sbunlock(&so->so_rcv); 1516 sounlock(so); 1517 splx(s); 1518 return error; 1519 } 1520 1521 int 1522 soshutdown(struct socket *so, int how) 1523 { 1524 const struct protosw *pr; 1525 int error; 1526 1527 KASSERT(solocked(so)); 1528 1529 pr = so->so_proto; 1530 if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) 1531 return (EINVAL); 1532 1533 if (how == SHUT_RD || how == SHUT_RDWR) { 1534 sorflush(so); 1535 error = 0; 1536 } 1537 if (how == SHUT_WR || how == SHUT_RDWR) 1538 error = (*pr->pr_usrreq)(so, PRU_SHUTDOWN, NULL, 1539 NULL, NULL, NULL); 1540 1541 return error; 1542 } 1543 1544 void 1545 sorflush(struct socket *so) 1546 { 1547 struct sockbuf *sb, asb; 1548 const struct protosw *pr; 1549 1550 KASSERT(solocked(so)); 1551 1552 sb = &so->so_rcv; 1553 pr = so->so_proto; 1554 socantrcvmore(so); 1555 sb->sb_flags |= SB_NOINTR; 1556 (void )sblock(sb, M_WAITOK); 1557 sbunlock(sb); 1558 asb = *sb; 1559 /* 1560 * Clear most of the sockbuf structure, but leave some of the 1561 * fields valid. 1562 */ 1563 memset(&sb->sb_startzero, 0, 1564 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); 1565 if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) { 1566 sounlock(so); 1567 (*pr->pr_domain->dom_dispose)(asb.sb_mb); 1568 solock(so); 1569 } 1570 sbrelease(&asb, so); 1571 } 1572 1573 static int 1574 sosetopt1(struct socket *so, int level, int optname, struct mbuf *m) 1575 { 1576 int optval, val; 1577 struct linger *l; 1578 struct sockbuf *sb; 1579 struct timeval *tv; 1580 1581 switch (optname) { 1582 1583 case SO_LINGER: 1584 if (m == NULL || m->m_len != sizeof(struct linger)) 1585 return EINVAL; 1586 l = mtod(m, struct linger *); 1587 if (l->l_linger < 0 || l->l_linger > USHRT_MAX || 1588 l->l_linger > (INT_MAX / hz)) 1589 return EDOM; 1590 so->so_linger = l->l_linger; 1591 if (l->l_onoff) 1592 so->so_options |= SO_LINGER; 1593 else 1594 so->so_options &= ~SO_LINGER; 1595 break; 1596 1597 case SO_DEBUG: 1598 case SO_KEEPALIVE: 1599 case SO_DONTROUTE: 1600 case SO_USELOOPBACK: 1601 case SO_BROADCAST: 1602 case SO_REUSEADDR: 1603 case SO_REUSEPORT: 1604 case SO_OOBINLINE: 1605 case SO_TIMESTAMP: 1606 if (m == NULL || m->m_len < sizeof(int)) 1607 return EINVAL; 1608 if (*mtod(m, int *)) 1609 so->so_options |= optname; 1610 else 1611 so->so_options &= ~optname; 1612 break; 1613 1614 case SO_SNDBUF: 1615 case SO_RCVBUF: 1616 case SO_SNDLOWAT: 1617 case SO_RCVLOWAT: 1618 if (m == NULL || m->m_len < sizeof(int)) 1619 return EINVAL; 1620 1621 /* 1622 * Values < 1 make no sense for any of these 1623 * options, so disallow them. 1624 */ 1625 optval = *mtod(m, int *); 1626 if (optval < 1) 1627 return EINVAL; 1628 1629 switch (optname) { 1630 1631 case SO_SNDBUF: 1632 case SO_RCVBUF: 1633 sb = (optname == SO_SNDBUF) ? 1634 &so->so_snd : &so->so_rcv; 1635 if (sbreserve(sb, (u_long)optval, so) == 0) 1636 return ENOBUFS; 1637 sb->sb_flags &= ~SB_AUTOSIZE; 1638 break; 1639 1640 /* 1641 * Make sure the low-water is never greater than 1642 * the high-water. 1643 */ 1644 case SO_SNDLOWAT: 1645 so->so_snd.sb_lowat = 1646 (optval > so->so_snd.sb_hiwat) ? 1647 so->so_snd.sb_hiwat : optval; 1648 break; 1649 case SO_RCVLOWAT: 1650 so->so_rcv.sb_lowat = 1651 (optval > so->so_rcv.sb_hiwat) ? 1652 so->so_rcv.sb_hiwat : optval; 1653 break; 1654 } 1655 break; 1656 1657 case SO_SNDTIMEO: 1658 case SO_RCVTIMEO: 1659 if (m == NULL || m->m_len < sizeof(*tv)) 1660 return EINVAL; 1661 tv = mtod(m, struct timeval *); 1662 if (tv->tv_sec > (INT_MAX - tv->tv_usec / tick) / hz) 1663 return EDOM; 1664 val = tv->tv_sec * hz + tv->tv_usec / tick; 1665 if (val == 0 && tv->tv_usec != 0) 1666 val = 1; 1667 1668 switch (optname) { 1669 1670 case SO_SNDTIMEO: 1671 so->so_snd.sb_timeo = val; 1672 break; 1673 case SO_RCVTIMEO: 1674 so->so_rcv.sb_timeo = val; 1675 break; 1676 } 1677 break; 1678 1679 default: 1680 return ENOPROTOOPT; 1681 } 1682 return 0; 1683 } 1684 1685 int 1686 sosetopt(struct socket *so, int level, int optname, struct mbuf *m) 1687 { 1688 int error, prerr; 1689 1690 solock(so); 1691 if (level == SOL_SOCKET) 1692 error = sosetopt1(so, level, optname, m); 1693 else 1694 error = ENOPROTOOPT; 1695 1696 if ((error == 0 || error == ENOPROTOOPT) && 1697 so->so_proto != NULL && so->so_proto->pr_ctloutput != NULL) { 1698 /* give the protocol stack a shot */ 1699 prerr = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, level, 1700 optname, &m); 1701 if (prerr == 0) 1702 error = 0; 1703 else if (prerr != ENOPROTOOPT) 1704 error = prerr; 1705 } else if (m != NULL) 1706 (void)m_free(m); 1707 sounlock(so); 1708 return error; 1709 } 1710 1711 int 1712 sogetopt(struct socket *so, int level, int optname, struct mbuf **mp) 1713 { 1714 struct mbuf *m; 1715 int error; 1716 1717 solock(so); 1718 if (level != SOL_SOCKET) { 1719 if (so->so_proto && so->so_proto->pr_ctloutput) { 1720 error = ((*so->so_proto->pr_ctloutput) 1721 (PRCO_GETOPT, so, level, optname, mp)); 1722 } else 1723 error = (ENOPROTOOPT); 1724 } else { 1725 m = m_get(M_WAIT, MT_SOOPTS); 1726 m->m_len = sizeof(int); 1727 1728 switch (optname) { 1729 1730 case SO_LINGER: 1731 m->m_len = sizeof(struct linger); 1732 mtod(m, struct linger *)->l_onoff = 1733 (so->so_options & SO_LINGER) ? 1 : 0; 1734 mtod(m, struct linger *)->l_linger = so->so_linger; 1735 break; 1736 1737 case SO_USELOOPBACK: 1738 case SO_DONTROUTE: 1739 case SO_DEBUG: 1740 case SO_KEEPALIVE: 1741 case SO_REUSEADDR: 1742 case SO_REUSEPORT: 1743 case SO_BROADCAST: 1744 case SO_OOBINLINE: 1745 case SO_TIMESTAMP: 1746 *mtod(m, int *) = (so->so_options & optname) ? 1 : 0; 1747 break; 1748 1749 case SO_TYPE: 1750 *mtod(m, int *) = so->so_type; 1751 break; 1752 1753 case SO_ERROR: 1754 *mtod(m, int *) = so->so_error; 1755 so->so_error = 0; 1756 break; 1757 1758 case SO_SNDBUF: 1759 *mtod(m, int *) = so->so_snd.sb_hiwat; 1760 break; 1761 1762 case SO_RCVBUF: 1763 *mtod(m, int *) = so->so_rcv.sb_hiwat; 1764 break; 1765 1766 case SO_SNDLOWAT: 1767 *mtod(m, int *) = so->so_snd.sb_lowat; 1768 break; 1769 1770 case SO_RCVLOWAT: 1771 *mtod(m, int *) = so->so_rcv.sb_lowat; 1772 break; 1773 1774 case SO_SNDTIMEO: 1775 case SO_RCVTIMEO: 1776 { 1777 int val = (optname == SO_SNDTIMEO ? 1778 so->so_snd.sb_timeo : so->so_rcv.sb_timeo); 1779 1780 m->m_len = sizeof(struct timeval); 1781 mtod(m, struct timeval *)->tv_sec = val / hz; 1782 mtod(m, struct timeval *)->tv_usec = 1783 (val % hz) * tick; 1784 break; 1785 } 1786 1787 case SO_OVERFLOWED: 1788 *mtod(m, int *) = so->so_rcv.sb_overflowed; 1789 break; 1790 1791 default: 1792 sounlock(so); 1793 (void)m_free(m); 1794 return (ENOPROTOOPT); 1795 } 1796 *mp = m; 1797 error = 0; 1798 } 1799 1800 sounlock(so); 1801 return (error); 1802 } 1803 1804 void 1805 sohasoutofband(struct socket *so) 1806 { 1807 1808 fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so); 1809 selnotify(&so->so_rcv.sb_sel, POLLPRI | POLLRDBAND, 0); 1810 } 1811 1812 static void 1813 filt_sordetach(struct knote *kn) 1814 { 1815 struct socket *so; 1816 1817 so = ((file_t *)kn->kn_obj)->f_data; 1818 solock(so); 1819 SLIST_REMOVE(&so->so_rcv.sb_sel.sel_klist, kn, knote, kn_selnext); 1820 if (SLIST_EMPTY(&so->so_rcv.sb_sel.sel_klist)) 1821 so->so_rcv.sb_flags &= ~SB_KNOTE; 1822 sounlock(so); 1823 } 1824 1825 /*ARGSUSED*/ 1826 static int 1827 filt_soread(struct knote *kn, long hint) 1828 { 1829 struct socket *so; 1830 int rv; 1831 1832 so = ((file_t *)kn->kn_obj)->f_data; 1833 if (hint != NOTE_SUBMIT) 1834 solock(so); 1835 kn->kn_data = so->so_rcv.sb_cc; 1836 if (so->so_state & SS_CANTRCVMORE) { 1837 kn->kn_flags |= EV_EOF; 1838 kn->kn_fflags = so->so_error; 1839 rv = 1; 1840 } else if (so->so_error) /* temporary udp error */ 1841 rv = 1; 1842 else if (kn->kn_sfflags & NOTE_LOWAT) 1843 rv = (kn->kn_data >= kn->kn_sdata); 1844 else 1845 rv = (kn->kn_data >= so->so_rcv.sb_lowat); 1846 if (hint != NOTE_SUBMIT) 1847 sounlock(so); 1848 return rv; 1849 } 1850 1851 static void 1852 filt_sowdetach(struct knote *kn) 1853 { 1854 struct socket *so; 1855 1856 so = ((file_t *)kn->kn_obj)->f_data; 1857 solock(so); 1858 SLIST_REMOVE(&so->so_snd.sb_sel.sel_klist, kn, knote, kn_selnext); 1859 if (SLIST_EMPTY(&so->so_snd.sb_sel.sel_klist)) 1860 so->so_snd.sb_flags &= ~SB_KNOTE; 1861 sounlock(so); 1862 } 1863 1864 /*ARGSUSED*/ 1865 static int 1866 filt_sowrite(struct knote *kn, long hint) 1867 { 1868 struct socket *so; 1869 int rv; 1870 1871 so = ((file_t *)kn->kn_obj)->f_data; 1872 if (hint != NOTE_SUBMIT) 1873 solock(so); 1874 kn->kn_data = sbspace(&so->so_snd); 1875 if (so->so_state & SS_CANTSENDMORE) { 1876 kn->kn_flags |= EV_EOF; 1877 kn->kn_fflags = so->so_error; 1878 rv = 1; 1879 } else if (so->so_error) /* temporary udp error */ 1880 rv = 1; 1881 else if (((so->so_state & SS_ISCONNECTED) == 0) && 1882 (so->so_proto->pr_flags & PR_CONNREQUIRED)) 1883 rv = 0; 1884 else if (kn->kn_sfflags & NOTE_LOWAT) 1885 rv = (kn->kn_data >= kn->kn_sdata); 1886 else 1887 rv = (kn->kn_data >= so->so_snd.sb_lowat); 1888 if (hint != NOTE_SUBMIT) 1889 sounlock(so); 1890 return rv; 1891 } 1892 1893 /*ARGSUSED*/ 1894 static int 1895 filt_solisten(struct knote *kn, long hint) 1896 { 1897 struct socket *so; 1898 int rv; 1899 1900 so = ((file_t *)kn->kn_obj)->f_data; 1901 1902 /* 1903 * Set kn_data to number of incoming connections, not 1904 * counting partial (incomplete) connections. 1905 */ 1906 if (hint != NOTE_SUBMIT) 1907 solock(so); 1908 kn->kn_data = so->so_qlen; 1909 rv = (kn->kn_data > 0); 1910 if (hint != NOTE_SUBMIT) 1911 sounlock(so); 1912 return rv; 1913 } 1914 1915 static const struct filterops solisten_filtops = 1916 { 1, NULL, filt_sordetach, filt_solisten }; 1917 static const struct filterops soread_filtops = 1918 { 1, NULL, filt_sordetach, filt_soread }; 1919 static const struct filterops sowrite_filtops = 1920 { 1, NULL, filt_sowdetach, filt_sowrite }; 1921 1922 int 1923 soo_kqfilter(struct file *fp, struct knote *kn) 1924 { 1925 struct socket *so; 1926 struct sockbuf *sb; 1927 1928 so = ((file_t *)kn->kn_obj)->f_data; 1929 solock(so); 1930 switch (kn->kn_filter) { 1931 case EVFILT_READ: 1932 if (so->so_options & SO_ACCEPTCONN) 1933 kn->kn_fop = &solisten_filtops; 1934 else 1935 kn->kn_fop = &soread_filtops; 1936 sb = &so->so_rcv; 1937 break; 1938 case EVFILT_WRITE: 1939 kn->kn_fop = &sowrite_filtops; 1940 sb = &so->so_snd; 1941 break; 1942 default: 1943 sounlock(so); 1944 return (EINVAL); 1945 } 1946 SLIST_INSERT_HEAD(&sb->sb_sel.sel_klist, kn, kn_selnext); 1947 sb->sb_flags |= SB_KNOTE; 1948 sounlock(so); 1949 return (0); 1950 } 1951 1952 static int 1953 sodopoll(struct socket *so, int events) 1954 { 1955 int revents; 1956 1957 revents = 0; 1958 1959 if (events & (POLLIN | POLLRDNORM)) 1960 if (soreadable(so)) 1961 revents |= events & (POLLIN | POLLRDNORM); 1962 1963 if (events & (POLLOUT | POLLWRNORM)) 1964 if (sowritable(so)) 1965 revents |= events & (POLLOUT | POLLWRNORM); 1966 1967 if (events & (POLLPRI | POLLRDBAND)) 1968 if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) 1969 revents |= events & (POLLPRI | POLLRDBAND); 1970 1971 return revents; 1972 } 1973 1974 int 1975 sopoll(struct socket *so, int events) 1976 { 1977 int revents = 0; 1978 1979 #ifndef DIAGNOSTIC 1980 /* 1981 * Do a quick, unlocked check in expectation that the socket 1982 * will be ready for I/O. Don't do this check if DIAGNOSTIC, 1983 * as the solocked() assertions will fail. 1984 */ 1985 if ((revents = sodopoll(so, events)) != 0) 1986 return revents; 1987 #endif 1988 1989 solock(so); 1990 if ((revents = sodopoll(so, events)) == 0) { 1991 if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) { 1992 selrecord(curlwp, &so->so_rcv.sb_sel); 1993 so->so_rcv.sb_flags |= SB_NOTIFY; 1994 } 1995 1996 if (events & (POLLOUT | POLLWRNORM)) { 1997 selrecord(curlwp, &so->so_snd.sb_sel); 1998 so->so_snd.sb_flags |= SB_NOTIFY; 1999 } 2000 } 2001 sounlock(so); 2002 2003 return revents; 2004 } 2005 2006 2007 #include <sys/sysctl.h> 2008 2009 static int sysctl_kern_somaxkva(SYSCTLFN_PROTO); 2010 2011 /* 2012 * sysctl helper routine for kern.somaxkva. ensures that the given 2013 * value is not too small. 2014 * (XXX should we maybe make sure it's not too large as well?) 2015 */ 2016 static int 2017 sysctl_kern_somaxkva(SYSCTLFN_ARGS) 2018 { 2019 int error, new_somaxkva; 2020 struct sysctlnode node; 2021 2022 new_somaxkva = somaxkva; 2023 node = *rnode; 2024 node.sysctl_data = &new_somaxkva; 2025 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2026 if (error || newp == NULL) 2027 return (error); 2028 2029 if (new_somaxkva < (16 * 1024 * 1024)) /* sanity */ 2030 return (EINVAL); 2031 2032 mutex_enter(&so_pendfree_lock); 2033 somaxkva = new_somaxkva; 2034 cv_broadcast(&socurkva_cv); 2035 mutex_exit(&so_pendfree_lock); 2036 2037 return (error); 2038 } 2039 2040 SYSCTL_SETUP(sysctl_kern_somaxkva_setup, "sysctl kern.somaxkva setup") 2041 { 2042 2043 sysctl_createv(clog, 0, NULL, NULL, 2044 CTLFLAG_PERMANENT, 2045 CTLTYPE_NODE, "kern", NULL, 2046 NULL, 0, NULL, 0, 2047 CTL_KERN, CTL_EOL); 2048 2049 sysctl_createv(clog, 0, NULL, NULL, 2050 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2051 CTLTYPE_INT, "somaxkva", 2052 SYSCTL_DESCR("Maximum amount of kernel memory to be " 2053 "used for socket buffers"), 2054 sysctl_kern_somaxkva, 0, NULL, 0, 2055 CTL_KERN, KERN_SOMAXKVA, CTL_EOL); 2056 } 2057