1 /* $NetBSD: uipc_socket.c,v 1.162 2008/04/28 20:24:05 martin 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 1.162 2008/04/28 20:24:05 martin 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 return (EOPNOTSUPP); 572 error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, NULL, 573 NULL, NULL, l); 574 if (error != 0) { 575 sounlock(so); 576 return error; 577 } 578 if (TAILQ_EMPTY(&so->so_q)) 579 so->so_options |= SO_ACCEPTCONN; 580 if (backlog < 0) 581 backlog = 0; 582 so->so_qlimit = min(backlog, somaxconn); 583 sounlock(so); 584 return 0; 585 } 586 587 void 588 sofree(struct socket *so) 589 { 590 u_int refs; 591 592 KASSERT(solocked(so)); 593 594 if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) { 595 sounlock(so); 596 return; 597 } 598 if (so->so_head) { 599 /* 600 * We must not decommission a socket that's on the accept(2) 601 * queue. If we do, then accept(2) may hang after select(2) 602 * indicated that the listening socket was ready. 603 */ 604 if (!soqremque(so, 0)) { 605 sounlock(so); 606 return; 607 } 608 } 609 if (so->so_rcv.sb_hiwat) 610 (void)chgsbsize(so->so_uidinfo, &so->so_rcv.sb_hiwat, 0, 611 RLIM_INFINITY); 612 if (so->so_snd.sb_hiwat) 613 (void)chgsbsize(so->so_uidinfo, &so->so_snd.sb_hiwat, 0, 614 RLIM_INFINITY); 615 sbrelease(&so->so_snd, so); 616 KASSERT(!cv_has_waiters(&so->so_cv)); 617 KASSERT(!cv_has_waiters(&so->so_rcv.sb_cv)); 618 KASSERT(!cv_has_waiters(&so->so_snd.sb_cv)); 619 sorflush(so); 620 refs = so->so_aborting; /* XXX */ 621 sounlock(so); 622 if (refs == 0) /* XXX */ 623 soput(so); 624 } 625 626 /* 627 * Close a socket on last file table reference removal. 628 * Initiate disconnect if connected. 629 * Free socket when disconnect complete. 630 */ 631 int 632 soclose(struct socket *so) 633 { 634 struct socket *so2; 635 int error; 636 int error2; 637 638 error = 0; 639 solock(so); 640 if (so->so_options & SO_ACCEPTCONN) { 641 do { 642 if ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) { 643 KASSERT(solocked2(so, so2)); 644 (void) soqremque(so2, 0); 645 /* soabort drops the lock. */ 646 (void) soabort(so2); 647 solock(so); 648 continue; 649 } 650 if ((so2 = TAILQ_FIRST(&so->so_q)) != 0) { 651 KASSERT(solocked2(so, so2)); 652 (void) soqremque(so2, 1); 653 /* soabort drops the lock. */ 654 (void) soabort(so2); 655 solock(so); 656 continue; 657 } 658 } while (0); 659 } 660 if (so->so_pcb == 0) 661 goto discard; 662 if (so->so_state & SS_ISCONNECTED) { 663 if ((so->so_state & SS_ISDISCONNECTING) == 0) { 664 error = sodisconnect(so); 665 if (error) 666 goto drop; 667 } 668 if (so->so_options & SO_LINGER) { 669 if ((so->so_state & SS_ISDISCONNECTING) && so->so_nbio) 670 goto drop; 671 while (so->so_state & SS_ISCONNECTED) { 672 error = sowait(so, so->so_linger * hz); 673 if (error) 674 break; 675 } 676 } 677 } 678 drop: 679 if (so->so_pcb) { 680 error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH, 681 NULL, NULL, NULL, NULL); 682 if (error == 0) 683 error = error2; 684 } 685 discard: 686 if (so->so_state & SS_NOFDREF) 687 panic("soclose: NOFDREF"); 688 so->so_state |= SS_NOFDREF; 689 sofree(so); 690 return (error); 691 } 692 693 /* 694 * Must be called with the socket locked.. Will return with it unlocked. 695 */ 696 int 697 soabort(struct socket *so) 698 { 699 u_int refs; 700 int error; 701 702 KASSERT(solocked(so)); 703 KASSERT(so->so_head == NULL); 704 705 so->so_aborting++; /* XXX */ 706 error = (*so->so_proto->pr_usrreq)(so, PRU_ABORT, NULL, 707 NULL, NULL, NULL); 708 refs = --so->so_aborting; /* XXX */ 709 if (error) { 710 sofree(so); 711 } else { 712 sounlock(so); 713 if (refs == 0) 714 sofree(so); 715 } 716 return error; 717 } 718 719 int 720 soaccept(struct socket *so, struct mbuf *nam) 721 { 722 int error; 723 724 KASSERT(solocked(so)); 725 726 error = 0; 727 if ((so->so_state & SS_NOFDREF) == 0) 728 panic("soaccept: !NOFDREF"); 729 so->so_state &= ~SS_NOFDREF; 730 if ((so->so_state & SS_ISDISCONNECTED) == 0 || 731 (so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0) 732 error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT, 733 NULL, nam, NULL, NULL); 734 else 735 error = ECONNABORTED; 736 737 return (error); 738 } 739 740 int 741 soconnect(struct socket *so, struct mbuf *nam, struct lwp *l) 742 { 743 int error; 744 745 KASSERT(solocked(so)); 746 747 if (so->so_options & SO_ACCEPTCONN) 748 return (EOPNOTSUPP); 749 /* 750 * If protocol is connection-based, can only connect once. 751 * Otherwise, if connected, try to disconnect first. 752 * This allows user to disconnect by connecting to, e.g., 753 * a null address. 754 */ 755 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) && 756 ((so->so_proto->pr_flags & PR_CONNREQUIRED) || 757 (error = sodisconnect(so)))) 758 error = EISCONN; 759 else 760 error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT, 761 NULL, nam, NULL, l); 762 return (error); 763 } 764 765 int 766 soconnect2(struct socket *so1, struct socket *so2) 767 { 768 int error; 769 770 KASSERT(solocked2(so1, so2)); 771 772 error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2, 773 NULL, (struct mbuf *)so2, NULL, NULL); 774 return (error); 775 } 776 777 int 778 sodisconnect(struct socket *so) 779 { 780 int error; 781 782 KASSERT(solocked(so)); 783 784 if ((so->so_state & SS_ISCONNECTED) == 0) { 785 error = ENOTCONN; 786 } else if (so->so_state & SS_ISDISCONNECTING) { 787 error = EALREADY; 788 } else { 789 error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT, 790 NULL, NULL, NULL, NULL); 791 } 792 sodopendfree(); 793 return (error); 794 } 795 796 #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK) 797 /* 798 * Send on a socket. 799 * If send must go all at once and message is larger than 800 * send buffering, then hard error. 801 * Lock against other senders. 802 * If must go all at once and not enough room now, then 803 * inform user that this would block and do nothing. 804 * Otherwise, if nonblocking, send as much as possible. 805 * The data to be sent is described by "uio" if nonzero, 806 * otherwise by the mbuf chain "top" (which must be null 807 * if uio is not). Data provided in mbuf chain must be small 808 * enough to send all at once. 809 * 810 * Returns nonzero on error, timeout or signal; callers 811 * must check for short counts if EINTR/ERESTART are returned. 812 * Data and control buffers are freed on return. 813 */ 814 int 815 sosend(struct socket *so, struct mbuf *addr, struct uio *uio, struct mbuf *top, 816 struct mbuf *control, int flags, struct lwp *l) 817 { 818 struct mbuf **mp, *m; 819 struct proc *p; 820 long space, len, resid, clen, mlen; 821 int error, s, dontroute, atomic; 822 823 p = l->l_proc; 824 sodopendfree(); 825 clen = 0; 826 827 /* 828 * solock() provides atomicity of access. splsoftnet() prevents 829 * protocol processing soft interrupts from interrupting us and 830 * blocking (expensive). 831 */ 832 s = splsoftnet(); 833 solock(so); 834 atomic = sosendallatonce(so) || top; 835 if (uio) 836 resid = uio->uio_resid; 837 else 838 resid = top->m_pkthdr.len; 839 /* 840 * In theory resid should be unsigned. 841 * However, space must be signed, as it might be less than 0 842 * if we over-committed, and we must use a signed comparison 843 * of space and resid. On the other hand, a negative resid 844 * causes us to loop sending 0-length segments to the protocol. 845 */ 846 if (resid < 0) { 847 error = EINVAL; 848 goto out; 849 } 850 dontroute = 851 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 && 852 (so->so_proto->pr_flags & PR_ATOMIC); 853 if (l) 854 l->l_ru.ru_msgsnd++; 855 if (control) 856 clen = control->m_len; 857 restart: 858 if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0) 859 goto out; 860 do { 861 if (so->so_state & SS_CANTSENDMORE) { 862 error = EPIPE; 863 goto release; 864 } 865 if (so->so_error) { 866 error = so->so_error; 867 so->so_error = 0; 868 goto release; 869 } 870 if ((so->so_state & SS_ISCONNECTED) == 0) { 871 if (so->so_proto->pr_flags & PR_CONNREQUIRED) { 872 if ((so->so_state & SS_ISCONFIRMING) == 0 && 873 !(resid == 0 && clen != 0)) { 874 error = ENOTCONN; 875 goto release; 876 } 877 } else if (addr == 0) { 878 error = EDESTADDRREQ; 879 goto release; 880 } 881 } 882 space = sbspace(&so->so_snd); 883 if (flags & MSG_OOB) 884 space += 1024; 885 if ((atomic && resid > so->so_snd.sb_hiwat) || 886 clen > so->so_snd.sb_hiwat) { 887 error = EMSGSIZE; 888 goto release; 889 } 890 if (space < resid + clen && 891 (atomic || space < so->so_snd.sb_lowat || space < clen)) { 892 if (so->so_nbio) { 893 error = EWOULDBLOCK; 894 goto release; 895 } 896 sbunlock(&so->so_snd); 897 error = sbwait(&so->so_snd); 898 if (error) 899 goto out; 900 goto restart; 901 } 902 mp = ⊤ 903 space -= clen; 904 do { 905 if (uio == NULL) { 906 /* 907 * Data is prepackaged in "top". 908 */ 909 resid = 0; 910 if (flags & MSG_EOR) 911 top->m_flags |= M_EOR; 912 } else do { 913 sounlock(so); 914 splx(s); 915 if (top == NULL) { 916 m = m_gethdr(M_WAIT, MT_DATA); 917 mlen = MHLEN; 918 m->m_pkthdr.len = 0; 919 m->m_pkthdr.rcvif = NULL; 920 } else { 921 m = m_get(M_WAIT, MT_DATA); 922 mlen = MLEN; 923 } 924 MCLAIM(m, so->so_snd.sb_mowner); 925 if (sock_loan_thresh >= 0 && 926 uio->uio_iov->iov_len >= sock_loan_thresh && 927 space >= sock_loan_thresh && 928 (len = sosend_loan(so, uio, m, 929 space)) != 0) { 930 SOSEND_COUNTER_INCR(&sosend_loan_big); 931 space -= len; 932 goto have_data; 933 } 934 if (resid >= MINCLSIZE && space >= MCLBYTES) { 935 SOSEND_COUNTER_INCR(&sosend_copy_big); 936 m_clget(m, M_WAIT); 937 if ((m->m_flags & M_EXT) == 0) 938 goto nopages; 939 mlen = MCLBYTES; 940 if (atomic && top == 0) { 941 len = lmin(MCLBYTES - max_hdr, 942 resid); 943 m->m_data += max_hdr; 944 } else 945 len = lmin(MCLBYTES, resid); 946 space -= len; 947 } else { 948 nopages: 949 SOSEND_COUNTER_INCR(&sosend_copy_small); 950 len = lmin(lmin(mlen, resid), space); 951 space -= len; 952 /* 953 * For datagram protocols, leave room 954 * for protocol headers in first mbuf. 955 */ 956 if (atomic && top == 0 && len < mlen) 957 MH_ALIGN(m, len); 958 } 959 error = uiomove(mtod(m, void *), (int)len, uio); 960 have_data: 961 resid = uio->uio_resid; 962 m->m_len = len; 963 *mp = m; 964 top->m_pkthdr.len += len; 965 s = splsoftnet(); 966 solock(so); 967 if (error != 0) 968 goto release; 969 mp = &m->m_next; 970 if (resid <= 0) { 971 if (flags & MSG_EOR) 972 top->m_flags |= M_EOR; 973 break; 974 } 975 } while (space > 0 && atomic); 976 977 if (so->so_state & SS_CANTSENDMORE) { 978 error = EPIPE; 979 goto release; 980 } 981 if (dontroute) 982 so->so_options |= SO_DONTROUTE; 983 if (resid > 0) 984 so->so_state |= SS_MORETOCOME; 985 error = (*so->so_proto->pr_usrreq)(so, 986 (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND, 987 top, addr, control, curlwp); 988 if (dontroute) 989 so->so_options &= ~SO_DONTROUTE; 990 if (resid > 0) 991 so->so_state &= ~SS_MORETOCOME; 992 clen = 0; 993 control = NULL; 994 top = NULL; 995 mp = ⊤ 996 if (error != 0) 997 goto release; 998 } while (resid && space > 0); 999 } while (resid); 1000 1001 release: 1002 sbunlock(&so->so_snd); 1003 out: 1004 sounlock(so); 1005 splx(s); 1006 if (top) 1007 m_freem(top); 1008 if (control) 1009 m_freem(control); 1010 return (error); 1011 } 1012 1013 /* 1014 * Following replacement or removal of the first mbuf on the first 1015 * mbuf chain of a socket buffer, push necessary state changes back 1016 * into the socket buffer so that other consumers see the values 1017 * consistently. 'nextrecord' is the callers locally stored value of 1018 * the original value of sb->sb_mb->m_nextpkt which must be restored 1019 * when the lead mbuf changes. NOTE: 'nextrecord' may be NULL. 1020 */ 1021 static void 1022 sbsync(struct sockbuf *sb, struct mbuf *nextrecord) 1023 { 1024 1025 KASSERT(solocked(sb->sb_so)); 1026 1027 /* 1028 * First, update for the new value of nextrecord. If necessary, 1029 * make it the first record. 1030 */ 1031 if (sb->sb_mb != NULL) 1032 sb->sb_mb->m_nextpkt = nextrecord; 1033 else 1034 sb->sb_mb = nextrecord; 1035 1036 /* 1037 * Now update any dependent socket buffer fields to reflect 1038 * the new state. This is an inline of SB_EMPTY_FIXUP, with 1039 * the addition of a second clause that takes care of the 1040 * case where sb_mb has been updated, but remains the last 1041 * record. 1042 */ 1043 if (sb->sb_mb == NULL) { 1044 sb->sb_mbtail = NULL; 1045 sb->sb_lastrecord = NULL; 1046 } else if (sb->sb_mb->m_nextpkt == NULL) 1047 sb->sb_lastrecord = sb->sb_mb; 1048 } 1049 1050 /* 1051 * Implement receive operations on a socket. 1052 * We depend on the way that records are added to the sockbuf 1053 * by sbappend*. In particular, each record (mbufs linked through m_next) 1054 * must begin with an address if the protocol so specifies, 1055 * followed by an optional mbuf or mbufs containing ancillary data, 1056 * and then zero or more mbufs of data. 1057 * In order to avoid blocking network interrupts for the entire time here, 1058 * we splx() while doing the actual copy to user space. 1059 * Although the sockbuf is locked, new data may still be appended, 1060 * and thus we must maintain consistency of the sockbuf during that time. 1061 * 1062 * The caller may receive the data as a single mbuf chain by supplying 1063 * an mbuf **mp0 for use in returning the chain. The uio is then used 1064 * only for the count in uio_resid. 1065 */ 1066 int 1067 soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio, 1068 struct mbuf **mp0, struct mbuf **controlp, int *flagsp) 1069 { 1070 struct lwp *l = curlwp; 1071 struct mbuf *m, **mp, *mt; 1072 int atomic, flags, len, error, s, offset, moff, type, orig_resid; 1073 const struct protosw *pr; 1074 struct mbuf *nextrecord; 1075 int mbuf_removed = 0; 1076 const struct domain *dom; 1077 1078 pr = so->so_proto; 1079 atomic = pr->pr_flags & PR_ATOMIC; 1080 dom = pr->pr_domain; 1081 mp = mp0; 1082 type = 0; 1083 orig_resid = uio->uio_resid; 1084 1085 if (paddr != NULL) 1086 *paddr = NULL; 1087 if (controlp != NULL) 1088 *controlp = NULL; 1089 if (flagsp != NULL) 1090 flags = *flagsp &~ MSG_EOR; 1091 else 1092 flags = 0; 1093 1094 if ((flags & MSG_DONTWAIT) == 0) 1095 sodopendfree(); 1096 1097 if (flags & MSG_OOB) { 1098 m = m_get(M_WAIT, MT_DATA); 1099 solock(so); 1100 error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m, 1101 (struct mbuf *)(long)(flags & MSG_PEEK), NULL, l); 1102 sounlock(so); 1103 if (error) 1104 goto bad; 1105 do { 1106 error = uiomove(mtod(m, void *), 1107 (int) min(uio->uio_resid, m->m_len), uio); 1108 m = m_free(m); 1109 } while (uio->uio_resid > 0 && error == 0 && m); 1110 bad: 1111 if (m != NULL) 1112 m_freem(m); 1113 return error; 1114 } 1115 if (mp != NULL) 1116 *mp = NULL; 1117 1118 /* 1119 * solock() provides atomicity of access. splsoftnet() prevents 1120 * protocol processing soft interrupts from interrupting us and 1121 * blocking (expensive). 1122 */ 1123 s = splsoftnet(); 1124 solock(so); 1125 if (so->so_state & SS_ISCONFIRMING && uio->uio_resid) 1126 (*pr->pr_usrreq)(so, PRU_RCVD, NULL, NULL, NULL, l); 1127 1128 restart: 1129 if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) { 1130 sounlock(so); 1131 splx(s); 1132 return error; 1133 } 1134 1135 m = so->so_rcv.sb_mb; 1136 /* 1137 * If we have less data than requested, block awaiting more 1138 * (subject to any timeout) if: 1139 * 1. the current count is less than the low water mark, 1140 * 2. MSG_WAITALL is set, and it is possible to do the entire 1141 * receive operation at once if we block (resid <= hiwat), or 1142 * 3. MSG_DONTWAIT is not set. 1143 * If MSG_WAITALL is set but resid is larger than the receive buffer, 1144 * we have to do the receive in sections, and thus risk returning 1145 * a short count if a timeout or signal occurs after we start. 1146 */ 1147 if (m == NULL || 1148 ((flags & MSG_DONTWAIT) == 0 && 1149 so->so_rcv.sb_cc < uio->uio_resid && 1150 (so->so_rcv.sb_cc < so->so_rcv.sb_lowat || 1151 ((flags & MSG_WAITALL) && 1152 uio->uio_resid <= so->so_rcv.sb_hiwat)) && 1153 m->m_nextpkt == NULL && !atomic)) { 1154 #ifdef DIAGNOSTIC 1155 if (m == NULL && so->so_rcv.sb_cc) 1156 panic("receive 1"); 1157 #endif 1158 if (so->so_error) { 1159 if (m != NULL) 1160 goto dontblock; 1161 error = so->so_error; 1162 if ((flags & MSG_PEEK) == 0) 1163 so->so_error = 0; 1164 goto release; 1165 } 1166 if (so->so_state & SS_CANTRCVMORE) { 1167 if (m != NULL) 1168 goto dontblock; 1169 else 1170 goto release; 1171 } 1172 for (; m != NULL; m = m->m_next) 1173 if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) { 1174 m = so->so_rcv.sb_mb; 1175 goto dontblock; 1176 } 1177 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 && 1178 (so->so_proto->pr_flags & PR_CONNREQUIRED)) { 1179 error = ENOTCONN; 1180 goto release; 1181 } 1182 if (uio->uio_resid == 0) 1183 goto release; 1184 if (so->so_nbio || (flags & MSG_DONTWAIT)) { 1185 error = EWOULDBLOCK; 1186 goto release; 1187 } 1188 SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1"); 1189 SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1"); 1190 sbunlock(&so->so_rcv); 1191 error = sbwait(&so->so_rcv); 1192 if (error != 0) { 1193 sounlock(so); 1194 splx(s); 1195 return error; 1196 } 1197 goto restart; 1198 } 1199 dontblock: 1200 /* 1201 * On entry here, m points to the first record of the socket buffer. 1202 * From this point onward, we maintain 'nextrecord' as a cache of the 1203 * pointer to the next record in the socket buffer. We must keep the 1204 * various socket buffer pointers and local stack versions of the 1205 * pointers in sync, pushing out modifications before dropping the 1206 * socket lock, and re-reading them when picking it up. 1207 * 1208 * Otherwise, we will race with the network stack appending new data 1209 * or records onto the socket buffer by using inconsistent/stale 1210 * versions of the field, possibly resulting in socket buffer 1211 * corruption. 1212 * 1213 * By holding the high-level sblock(), we prevent simultaneous 1214 * readers from pulling off the front of the socket buffer. 1215 */ 1216 if (l != NULL) 1217 l->l_ru.ru_msgrcv++; 1218 KASSERT(m == so->so_rcv.sb_mb); 1219 SBLASTRECORDCHK(&so->so_rcv, "soreceive 1"); 1220 SBLASTMBUFCHK(&so->so_rcv, "soreceive 1"); 1221 nextrecord = m->m_nextpkt; 1222 if (pr->pr_flags & PR_ADDR) { 1223 #ifdef DIAGNOSTIC 1224 if (m->m_type != MT_SONAME) 1225 panic("receive 1a"); 1226 #endif 1227 orig_resid = 0; 1228 if (flags & MSG_PEEK) { 1229 if (paddr) 1230 *paddr = m_copy(m, 0, m->m_len); 1231 m = m->m_next; 1232 } else { 1233 sbfree(&so->so_rcv, m); 1234 mbuf_removed = 1; 1235 if (paddr != NULL) { 1236 *paddr = m; 1237 so->so_rcv.sb_mb = m->m_next; 1238 m->m_next = NULL; 1239 m = so->so_rcv.sb_mb; 1240 } else { 1241 MFREE(m, so->so_rcv.sb_mb); 1242 m = so->so_rcv.sb_mb; 1243 } 1244 sbsync(&so->so_rcv, nextrecord); 1245 } 1246 } 1247 1248 /* 1249 * Process one or more MT_CONTROL mbufs present before any data mbufs 1250 * in the first mbuf chain on the socket buffer. If MSG_PEEK, we 1251 * just copy the data; if !MSG_PEEK, we call into the protocol to 1252 * perform externalization (or freeing if controlp == NULL). 1253 */ 1254 if (__predict_false(m != NULL && m->m_type == MT_CONTROL)) { 1255 struct mbuf *cm = NULL, *cmn; 1256 struct mbuf **cme = &cm; 1257 1258 do { 1259 if (flags & MSG_PEEK) { 1260 if (controlp != NULL) { 1261 *controlp = m_copy(m, 0, m->m_len); 1262 controlp = &(*controlp)->m_next; 1263 } 1264 m = m->m_next; 1265 } else { 1266 sbfree(&so->so_rcv, m); 1267 so->so_rcv.sb_mb = m->m_next; 1268 m->m_next = NULL; 1269 *cme = m; 1270 cme = &(*cme)->m_next; 1271 m = so->so_rcv.sb_mb; 1272 } 1273 } while (m != NULL && m->m_type == MT_CONTROL); 1274 if ((flags & MSG_PEEK) == 0) 1275 sbsync(&so->so_rcv, nextrecord); 1276 for (; cm != NULL; cm = cmn) { 1277 cmn = cm->m_next; 1278 cm->m_next = NULL; 1279 type = mtod(cm, struct cmsghdr *)->cmsg_type; 1280 if (controlp != NULL) { 1281 if (dom->dom_externalize != NULL && 1282 type == SCM_RIGHTS) { 1283 sounlock(so); 1284 splx(s); 1285 error = (*dom->dom_externalize)(cm, l); 1286 s = splsoftnet(); 1287 solock(so); 1288 } 1289 *controlp = cm; 1290 while (*controlp != NULL) 1291 controlp = &(*controlp)->m_next; 1292 } else { 1293 /* 1294 * Dispose of any SCM_RIGHTS message that went 1295 * through the read path rather than recv. 1296 */ 1297 if (dom->dom_dispose != NULL && 1298 type == SCM_RIGHTS) { 1299 sounlock(so); 1300 (*dom->dom_dispose)(cm); 1301 solock(so); 1302 } 1303 m_freem(cm); 1304 } 1305 } 1306 if (m != NULL) 1307 nextrecord = so->so_rcv.sb_mb->m_nextpkt; 1308 else 1309 nextrecord = so->so_rcv.sb_mb; 1310 orig_resid = 0; 1311 } 1312 1313 /* If m is non-NULL, we have some data to read. */ 1314 if (__predict_true(m != NULL)) { 1315 type = m->m_type; 1316 if (type == MT_OOBDATA) 1317 flags |= MSG_OOB; 1318 } 1319 SBLASTRECORDCHK(&so->so_rcv, "soreceive 2"); 1320 SBLASTMBUFCHK(&so->so_rcv, "soreceive 2"); 1321 1322 moff = 0; 1323 offset = 0; 1324 while (m != NULL && uio->uio_resid > 0 && error == 0) { 1325 if (m->m_type == MT_OOBDATA) { 1326 if (type != MT_OOBDATA) 1327 break; 1328 } else if (type == MT_OOBDATA) 1329 break; 1330 #ifdef DIAGNOSTIC 1331 else if (m->m_type != MT_DATA && m->m_type != MT_HEADER) 1332 panic("receive 3"); 1333 #endif 1334 so->so_state &= ~SS_RCVATMARK; 1335 len = uio->uio_resid; 1336 if (so->so_oobmark && len > so->so_oobmark - offset) 1337 len = so->so_oobmark - offset; 1338 if (len > m->m_len - moff) 1339 len = m->m_len - moff; 1340 /* 1341 * If mp is set, just pass back the mbufs. 1342 * Otherwise copy them out via the uio, then free. 1343 * Sockbuf must be consistent here (points to current mbuf, 1344 * it points to next record) when we drop priority; 1345 * we must note any additions to the sockbuf when we 1346 * block interrupts again. 1347 */ 1348 if (mp == NULL) { 1349 SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove"); 1350 SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove"); 1351 sounlock(so); 1352 splx(s); 1353 error = uiomove(mtod(m, char *) + moff, (int)len, uio); 1354 s = splsoftnet(); 1355 solock(so); 1356 if (error != 0) { 1357 /* 1358 * If any part of the record has been removed 1359 * (such as the MT_SONAME mbuf, which will 1360 * happen when PR_ADDR, and thus also 1361 * PR_ATOMIC, is set), then drop the entire 1362 * record to maintain the atomicity of the 1363 * receive operation. 1364 * 1365 * This avoids a later panic("receive 1a") 1366 * when compiled with DIAGNOSTIC. 1367 */ 1368 if (m && mbuf_removed && atomic) 1369 (void) sbdroprecord(&so->so_rcv); 1370 1371 goto release; 1372 } 1373 } else 1374 uio->uio_resid -= len; 1375 if (len == m->m_len - moff) { 1376 if (m->m_flags & M_EOR) 1377 flags |= MSG_EOR; 1378 if (flags & MSG_PEEK) { 1379 m = m->m_next; 1380 moff = 0; 1381 } else { 1382 nextrecord = m->m_nextpkt; 1383 sbfree(&so->so_rcv, m); 1384 if (mp) { 1385 *mp = m; 1386 mp = &m->m_next; 1387 so->so_rcv.sb_mb = m = m->m_next; 1388 *mp = NULL; 1389 } else { 1390 MFREE(m, so->so_rcv.sb_mb); 1391 m = so->so_rcv.sb_mb; 1392 } 1393 /* 1394 * If m != NULL, we also know that 1395 * so->so_rcv.sb_mb != NULL. 1396 */ 1397 KASSERT(so->so_rcv.sb_mb == m); 1398 if (m) { 1399 m->m_nextpkt = nextrecord; 1400 if (nextrecord == NULL) 1401 so->so_rcv.sb_lastrecord = m; 1402 } else { 1403 so->so_rcv.sb_mb = nextrecord; 1404 SB_EMPTY_FIXUP(&so->so_rcv); 1405 } 1406 SBLASTRECORDCHK(&so->so_rcv, "soreceive 3"); 1407 SBLASTMBUFCHK(&so->so_rcv, "soreceive 3"); 1408 } 1409 } else if (flags & MSG_PEEK) 1410 moff += len; 1411 else { 1412 if (mp != NULL) { 1413 mt = m_copym(m, 0, len, M_NOWAIT); 1414 if (__predict_false(mt == NULL)) { 1415 sounlock(so); 1416 mt = m_copym(m, 0, len, M_WAIT); 1417 solock(so); 1418 } 1419 *mp = mt; 1420 } 1421 m->m_data += len; 1422 m->m_len -= len; 1423 so->so_rcv.sb_cc -= len; 1424 } 1425 if (so->so_oobmark) { 1426 if ((flags & MSG_PEEK) == 0) { 1427 so->so_oobmark -= len; 1428 if (so->so_oobmark == 0) { 1429 so->so_state |= SS_RCVATMARK; 1430 break; 1431 } 1432 } else { 1433 offset += len; 1434 if (offset == so->so_oobmark) 1435 break; 1436 } 1437 } 1438 if (flags & MSG_EOR) 1439 break; 1440 /* 1441 * If the MSG_WAITALL flag is set (for non-atomic socket), 1442 * we must not quit until "uio->uio_resid == 0" or an error 1443 * termination. If a signal/timeout occurs, return 1444 * with a short count but without error. 1445 * Keep sockbuf locked against other readers. 1446 */ 1447 while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 && 1448 !sosendallatonce(so) && !nextrecord) { 1449 if (so->so_error || so->so_state & SS_CANTRCVMORE) 1450 break; 1451 /* 1452 * If we are peeking and the socket receive buffer is 1453 * full, stop since we can't get more data to peek at. 1454 */ 1455 if ((flags & MSG_PEEK) && sbspace(&so->so_rcv) <= 0) 1456 break; 1457 /* 1458 * If we've drained the socket buffer, tell the 1459 * protocol in case it needs to do something to 1460 * get it filled again. 1461 */ 1462 if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb) 1463 (*pr->pr_usrreq)(so, PRU_RCVD, 1464 NULL, (struct mbuf *)(long)flags, NULL, l); 1465 SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2"); 1466 SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2"); 1467 error = sbwait(&so->so_rcv); 1468 if (error != 0) { 1469 sbunlock(&so->so_rcv); 1470 sounlock(so); 1471 splx(s); 1472 return 0; 1473 } 1474 if ((m = so->so_rcv.sb_mb) != NULL) 1475 nextrecord = m->m_nextpkt; 1476 } 1477 } 1478 1479 if (m && atomic) { 1480 flags |= MSG_TRUNC; 1481 if ((flags & MSG_PEEK) == 0) 1482 (void) sbdroprecord(&so->so_rcv); 1483 } 1484 if ((flags & MSG_PEEK) == 0) { 1485 if (m == NULL) { 1486 /* 1487 * First part is an inline SB_EMPTY_FIXUP(). Second 1488 * part makes sure sb_lastrecord is up-to-date if 1489 * there is still data in the socket buffer. 1490 */ 1491 so->so_rcv.sb_mb = nextrecord; 1492 if (so->so_rcv.sb_mb == NULL) { 1493 so->so_rcv.sb_mbtail = NULL; 1494 so->so_rcv.sb_lastrecord = NULL; 1495 } else if (nextrecord->m_nextpkt == NULL) 1496 so->so_rcv.sb_lastrecord = nextrecord; 1497 } 1498 SBLASTRECORDCHK(&so->so_rcv, "soreceive 4"); 1499 SBLASTMBUFCHK(&so->so_rcv, "soreceive 4"); 1500 if (pr->pr_flags & PR_WANTRCVD && so->so_pcb) 1501 (*pr->pr_usrreq)(so, PRU_RCVD, NULL, 1502 (struct mbuf *)(long)flags, NULL, l); 1503 } 1504 if (orig_resid == uio->uio_resid && orig_resid && 1505 (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) { 1506 sbunlock(&so->so_rcv); 1507 goto restart; 1508 } 1509 1510 if (flagsp != NULL) 1511 *flagsp |= flags; 1512 release: 1513 sbunlock(&so->so_rcv); 1514 sounlock(so); 1515 splx(s); 1516 return error; 1517 } 1518 1519 int 1520 soshutdown(struct socket *so, int how) 1521 { 1522 const struct protosw *pr; 1523 int error; 1524 1525 KASSERT(solocked(so)); 1526 1527 pr = so->so_proto; 1528 if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR)) 1529 return (EINVAL); 1530 1531 if (how == SHUT_RD || how == SHUT_RDWR) { 1532 sorflush(so); 1533 error = 0; 1534 } 1535 if (how == SHUT_WR || how == SHUT_RDWR) 1536 error = (*pr->pr_usrreq)(so, PRU_SHUTDOWN, NULL, 1537 NULL, NULL, NULL); 1538 1539 return error; 1540 } 1541 1542 void 1543 sorflush(struct socket *so) 1544 { 1545 struct sockbuf *sb, asb; 1546 const struct protosw *pr; 1547 1548 KASSERT(solocked(so)); 1549 1550 sb = &so->so_rcv; 1551 pr = so->so_proto; 1552 socantrcvmore(so); 1553 sb->sb_flags |= SB_NOINTR; 1554 (void )sblock(sb, M_WAITOK); 1555 sbunlock(sb); 1556 asb = *sb; 1557 /* 1558 * Clear most of the sockbuf structure, but leave some of the 1559 * fields valid. 1560 */ 1561 memset(&sb->sb_startzero, 0, 1562 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero)); 1563 if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) { 1564 sounlock(so); 1565 (*pr->pr_domain->dom_dispose)(asb.sb_mb); 1566 solock(so); 1567 } 1568 sbrelease(&asb, so); 1569 } 1570 1571 static int 1572 sosetopt1(struct socket *so, int level, int optname, struct mbuf *m) 1573 { 1574 int optval, val; 1575 struct linger *l; 1576 struct sockbuf *sb; 1577 struct timeval *tv; 1578 1579 switch (optname) { 1580 1581 case SO_LINGER: 1582 if (m == NULL || m->m_len != sizeof(struct linger)) 1583 return EINVAL; 1584 l = mtod(m, struct linger *); 1585 if (l->l_linger < 0 || l->l_linger > USHRT_MAX || 1586 l->l_linger > (INT_MAX / hz)) 1587 return EDOM; 1588 so->so_linger = l->l_linger; 1589 if (l->l_onoff) 1590 so->so_options |= SO_LINGER; 1591 else 1592 so->so_options &= ~SO_LINGER; 1593 break; 1594 1595 case SO_DEBUG: 1596 case SO_KEEPALIVE: 1597 case SO_DONTROUTE: 1598 case SO_USELOOPBACK: 1599 case SO_BROADCAST: 1600 case SO_REUSEADDR: 1601 case SO_REUSEPORT: 1602 case SO_OOBINLINE: 1603 case SO_TIMESTAMP: 1604 if (m == NULL || m->m_len < sizeof(int)) 1605 return EINVAL; 1606 if (*mtod(m, int *)) 1607 so->so_options |= optname; 1608 else 1609 so->so_options &= ~optname; 1610 break; 1611 1612 case SO_SNDBUF: 1613 case SO_RCVBUF: 1614 case SO_SNDLOWAT: 1615 case SO_RCVLOWAT: 1616 if (m == NULL || m->m_len < sizeof(int)) 1617 return EINVAL; 1618 1619 /* 1620 * Values < 1 make no sense for any of these 1621 * options, so disallow them. 1622 */ 1623 optval = *mtod(m, int *); 1624 if (optval < 1) 1625 return EINVAL; 1626 1627 switch (optname) { 1628 1629 case SO_SNDBUF: 1630 case SO_RCVBUF: 1631 sb = (optname == SO_SNDBUF) ? 1632 &so->so_snd : &so->so_rcv; 1633 if (sbreserve(sb, (u_long)optval, so) == 0) 1634 return ENOBUFS; 1635 sb->sb_flags &= ~SB_AUTOSIZE; 1636 break; 1637 1638 /* 1639 * Make sure the low-water is never greater than 1640 * the high-water. 1641 */ 1642 case SO_SNDLOWAT: 1643 so->so_snd.sb_lowat = 1644 (optval > so->so_snd.sb_hiwat) ? 1645 so->so_snd.sb_hiwat : optval; 1646 break; 1647 case SO_RCVLOWAT: 1648 so->so_rcv.sb_lowat = 1649 (optval > so->so_rcv.sb_hiwat) ? 1650 so->so_rcv.sb_hiwat : optval; 1651 break; 1652 } 1653 break; 1654 1655 case SO_SNDTIMEO: 1656 case SO_RCVTIMEO: 1657 if (m == NULL || m->m_len < sizeof(*tv)) 1658 return EINVAL; 1659 tv = mtod(m, struct timeval *); 1660 if (tv->tv_sec > (INT_MAX - tv->tv_usec / tick) / hz) 1661 return EDOM; 1662 val = tv->tv_sec * hz + tv->tv_usec / tick; 1663 if (val == 0 && tv->tv_usec != 0) 1664 val = 1; 1665 1666 switch (optname) { 1667 1668 case SO_SNDTIMEO: 1669 so->so_snd.sb_timeo = val; 1670 break; 1671 case SO_RCVTIMEO: 1672 so->so_rcv.sb_timeo = val; 1673 break; 1674 } 1675 break; 1676 1677 default: 1678 return ENOPROTOOPT; 1679 } 1680 return 0; 1681 } 1682 1683 int 1684 sosetopt(struct socket *so, int level, int optname, struct mbuf *m) 1685 { 1686 int error, prerr; 1687 1688 solock(so); 1689 if (level == SOL_SOCKET) 1690 error = sosetopt1(so, level, optname, m); 1691 else 1692 error = ENOPROTOOPT; 1693 1694 if ((error == 0 || error == ENOPROTOOPT) && 1695 so->so_proto != NULL && so->so_proto->pr_ctloutput != NULL) { 1696 /* give the protocol stack a shot */ 1697 prerr = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, level, 1698 optname, &m); 1699 if (prerr == 0) 1700 error = 0; 1701 else if (prerr != ENOPROTOOPT) 1702 error = prerr; 1703 } else if (m != NULL) 1704 (void)m_free(m); 1705 sounlock(so); 1706 return error; 1707 } 1708 1709 int 1710 sogetopt(struct socket *so, int level, int optname, struct mbuf **mp) 1711 { 1712 struct mbuf *m; 1713 int error; 1714 1715 solock(so); 1716 if (level != SOL_SOCKET) { 1717 if (so->so_proto && so->so_proto->pr_ctloutput) { 1718 error = ((*so->so_proto->pr_ctloutput) 1719 (PRCO_GETOPT, so, level, optname, mp)); 1720 } else 1721 error = (ENOPROTOOPT); 1722 } else { 1723 m = m_get(M_WAIT, MT_SOOPTS); 1724 m->m_len = sizeof(int); 1725 1726 switch (optname) { 1727 1728 case SO_LINGER: 1729 m->m_len = sizeof(struct linger); 1730 mtod(m, struct linger *)->l_onoff = 1731 (so->so_options & SO_LINGER) ? 1 : 0; 1732 mtod(m, struct linger *)->l_linger = so->so_linger; 1733 break; 1734 1735 case SO_USELOOPBACK: 1736 case SO_DONTROUTE: 1737 case SO_DEBUG: 1738 case SO_KEEPALIVE: 1739 case SO_REUSEADDR: 1740 case SO_REUSEPORT: 1741 case SO_BROADCAST: 1742 case SO_OOBINLINE: 1743 case SO_TIMESTAMP: 1744 *mtod(m, int *) = (so->so_options & optname) ? 1 : 0; 1745 break; 1746 1747 case SO_TYPE: 1748 *mtod(m, int *) = so->so_type; 1749 break; 1750 1751 case SO_ERROR: 1752 *mtod(m, int *) = so->so_error; 1753 so->so_error = 0; 1754 break; 1755 1756 case SO_SNDBUF: 1757 *mtod(m, int *) = so->so_snd.sb_hiwat; 1758 break; 1759 1760 case SO_RCVBUF: 1761 *mtod(m, int *) = so->so_rcv.sb_hiwat; 1762 break; 1763 1764 case SO_SNDLOWAT: 1765 *mtod(m, int *) = so->so_snd.sb_lowat; 1766 break; 1767 1768 case SO_RCVLOWAT: 1769 *mtod(m, int *) = so->so_rcv.sb_lowat; 1770 break; 1771 1772 case SO_SNDTIMEO: 1773 case SO_RCVTIMEO: 1774 { 1775 int val = (optname == SO_SNDTIMEO ? 1776 so->so_snd.sb_timeo : so->so_rcv.sb_timeo); 1777 1778 m->m_len = sizeof(struct timeval); 1779 mtod(m, struct timeval *)->tv_sec = val / hz; 1780 mtod(m, struct timeval *)->tv_usec = 1781 (val % hz) * tick; 1782 break; 1783 } 1784 1785 case SO_OVERFLOWED: 1786 *mtod(m, int *) = so->so_rcv.sb_overflowed; 1787 break; 1788 1789 default: 1790 sounlock(so); 1791 (void)m_free(m); 1792 return (ENOPROTOOPT); 1793 } 1794 *mp = m; 1795 error = 0; 1796 } 1797 1798 sounlock(so); 1799 return (error); 1800 } 1801 1802 void 1803 sohasoutofband(struct socket *so) 1804 { 1805 1806 fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so); 1807 selnotify(&so->so_rcv.sb_sel, POLLPRI | POLLRDBAND, 0); 1808 } 1809 1810 static void 1811 filt_sordetach(struct knote *kn) 1812 { 1813 struct socket *so; 1814 1815 so = ((file_t *)kn->kn_obj)->f_data; 1816 solock(so); 1817 SLIST_REMOVE(&so->so_rcv.sb_sel.sel_klist, kn, knote, kn_selnext); 1818 if (SLIST_EMPTY(&so->so_rcv.sb_sel.sel_klist)) 1819 so->so_rcv.sb_flags &= ~SB_KNOTE; 1820 sounlock(so); 1821 } 1822 1823 /*ARGSUSED*/ 1824 static int 1825 filt_soread(struct knote *kn, long hint) 1826 { 1827 struct socket *so; 1828 int rv; 1829 1830 so = ((file_t *)kn->kn_obj)->f_data; 1831 if (hint != NOTE_SUBMIT) 1832 solock(so); 1833 kn->kn_data = so->so_rcv.sb_cc; 1834 if (so->so_state & SS_CANTRCVMORE) { 1835 kn->kn_flags |= EV_EOF; 1836 kn->kn_fflags = so->so_error; 1837 rv = 1; 1838 } else if (so->so_error) /* temporary udp error */ 1839 rv = 1; 1840 else if (kn->kn_sfflags & NOTE_LOWAT) 1841 rv = (kn->kn_data >= kn->kn_sdata); 1842 else 1843 rv = (kn->kn_data >= so->so_rcv.sb_lowat); 1844 if (hint != NOTE_SUBMIT) 1845 sounlock(so); 1846 return rv; 1847 } 1848 1849 static void 1850 filt_sowdetach(struct knote *kn) 1851 { 1852 struct socket *so; 1853 1854 so = ((file_t *)kn->kn_obj)->f_data; 1855 solock(so); 1856 SLIST_REMOVE(&so->so_snd.sb_sel.sel_klist, kn, knote, kn_selnext); 1857 if (SLIST_EMPTY(&so->so_snd.sb_sel.sel_klist)) 1858 so->so_snd.sb_flags &= ~SB_KNOTE; 1859 sounlock(so); 1860 } 1861 1862 /*ARGSUSED*/ 1863 static int 1864 filt_sowrite(struct knote *kn, long hint) 1865 { 1866 struct socket *so; 1867 int rv; 1868 1869 so = ((file_t *)kn->kn_obj)->f_data; 1870 if (hint != NOTE_SUBMIT) 1871 solock(so); 1872 kn->kn_data = sbspace(&so->so_snd); 1873 if (so->so_state & SS_CANTSENDMORE) { 1874 kn->kn_flags |= EV_EOF; 1875 kn->kn_fflags = so->so_error; 1876 rv = 1; 1877 } else if (so->so_error) /* temporary udp error */ 1878 rv = 1; 1879 else if (((so->so_state & SS_ISCONNECTED) == 0) && 1880 (so->so_proto->pr_flags & PR_CONNREQUIRED)) 1881 rv = 0; 1882 else if (kn->kn_sfflags & NOTE_LOWAT) 1883 rv = (kn->kn_data >= kn->kn_sdata); 1884 else 1885 rv = (kn->kn_data >= so->so_snd.sb_lowat); 1886 if (hint != NOTE_SUBMIT) 1887 sounlock(so); 1888 return rv; 1889 } 1890 1891 /*ARGSUSED*/ 1892 static int 1893 filt_solisten(struct knote *kn, long hint) 1894 { 1895 struct socket *so; 1896 int rv; 1897 1898 so = ((file_t *)kn->kn_obj)->f_data; 1899 1900 /* 1901 * Set kn_data to number of incoming connections, not 1902 * counting partial (incomplete) connections. 1903 */ 1904 if (hint != NOTE_SUBMIT) 1905 solock(so); 1906 kn->kn_data = so->so_qlen; 1907 rv = (kn->kn_data > 0); 1908 if (hint != NOTE_SUBMIT) 1909 sounlock(so); 1910 return rv; 1911 } 1912 1913 static const struct filterops solisten_filtops = 1914 { 1, NULL, filt_sordetach, filt_solisten }; 1915 static const struct filterops soread_filtops = 1916 { 1, NULL, filt_sordetach, filt_soread }; 1917 static const struct filterops sowrite_filtops = 1918 { 1, NULL, filt_sowdetach, filt_sowrite }; 1919 1920 int 1921 soo_kqfilter(struct file *fp, struct knote *kn) 1922 { 1923 struct socket *so; 1924 struct sockbuf *sb; 1925 1926 so = ((file_t *)kn->kn_obj)->f_data; 1927 solock(so); 1928 switch (kn->kn_filter) { 1929 case EVFILT_READ: 1930 if (so->so_options & SO_ACCEPTCONN) 1931 kn->kn_fop = &solisten_filtops; 1932 else 1933 kn->kn_fop = &soread_filtops; 1934 sb = &so->so_rcv; 1935 break; 1936 case EVFILT_WRITE: 1937 kn->kn_fop = &sowrite_filtops; 1938 sb = &so->so_snd; 1939 break; 1940 default: 1941 sounlock(so); 1942 return (EINVAL); 1943 } 1944 SLIST_INSERT_HEAD(&sb->sb_sel.sel_klist, kn, kn_selnext); 1945 sb->sb_flags |= SB_KNOTE; 1946 sounlock(so); 1947 return (0); 1948 } 1949 1950 static int 1951 sodopoll(struct socket *so, int events) 1952 { 1953 int revents; 1954 1955 revents = 0; 1956 1957 if (events & (POLLIN | POLLRDNORM)) 1958 if (soreadable(so)) 1959 revents |= events & (POLLIN | POLLRDNORM); 1960 1961 if (events & (POLLOUT | POLLWRNORM)) 1962 if (sowritable(so)) 1963 revents |= events & (POLLOUT | POLLWRNORM); 1964 1965 if (events & (POLLPRI | POLLRDBAND)) 1966 if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) 1967 revents |= events & (POLLPRI | POLLRDBAND); 1968 1969 return revents; 1970 } 1971 1972 int 1973 sopoll(struct socket *so, int events) 1974 { 1975 int revents = 0; 1976 1977 #ifndef DIAGNOSTIC 1978 /* 1979 * Do a quick, unlocked check in expectation that the socket 1980 * will be ready for I/O. Don't do this check if DIAGNOSTIC, 1981 * as the solocked() assertions will fail. 1982 */ 1983 if ((revents = sodopoll(so, events)) != 0) 1984 return revents; 1985 #endif 1986 1987 solock(so); 1988 if ((revents = sodopoll(so, events)) == 0) { 1989 if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) { 1990 selrecord(curlwp, &so->so_rcv.sb_sel); 1991 so->so_rcv.sb_flags |= SB_NOTIFY; 1992 } 1993 1994 if (events & (POLLOUT | POLLWRNORM)) { 1995 selrecord(curlwp, &so->so_snd.sb_sel); 1996 so->so_snd.sb_flags |= SB_NOTIFY; 1997 } 1998 } 1999 sounlock(so); 2000 2001 return revents; 2002 } 2003 2004 2005 #include <sys/sysctl.h> 2006 2007 static int sysctl_kern_somaxkva(SYSCTLFN_PROTO); 2008 2009 /* 2010 * sysctl helper routine for kern.somaxkva. ensures that the given 2011 * value is not too small. 2012 * (XXX should we maybe make sure it's not too large as well?) 2013 */ 2014 static int 2015 sysctl_kern_somaxkva(SYSCTLFN_ARGS) 2016 { 2017 int error, new_somaxkva; 2018 struct sysctlnode node; 2019 2020 new_somaxkva = somaxkva; 2021 node = *rnode; 2022 node.sysctl_data = &new_somaxkva; 2023 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2024 if (error || newp == NULL) 2025 return (error); 2026 2027 if (new_somaxkva < (16 * 1024 * 1024)) /* sanity */ 2028 return (EINVAL); 2029 2030 mutex_enter(&so_pendfree_lock); 2031 somaxkva = new_somaxkva; 2032 cv_broadcast(&socurkva_cv); 2033 mutex_exit(&so_pendfree_lock); 2034 2035 return (error); 2036 } 2037 2038 SYSCTL_SETUP(sysctl_kern_somaxkva_setup, "sysctl kern.somaxkva setup") 2039 { 2040 2041 sysctl_createv(clog, 0, NULL, NULL, 2042 CTLFLAG_PERMANENT, 2043 CTLTYPE_NODE, "kern", NULL, 2044 NULL, 0, NULL, 0, 2045 CTL_KERN, CTL_EOL); 2046 2047 sysctl_createv(clog, 0, NULL, NULL, 2048 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2049 CTLTYPE_INT, "somaxkva", 2050 SYSCTL_DESCR("Maximum amount of kernel memory to be " 2051 "used for socket buffers"), 2052 sysctl_kern_somaxkva, 0, NULL, 0, 2053 CTL_KERN, KERN_SOMAXKVA, CTL_EOL); 2054 } 2055