uipc_socket.c revision 1.160.2.3 1 /* $NetBSD: uipc_socket.c,v 1.160.2.3 2009/09/16 13:38:01 yamt Exp $ */
2
3 /*-
4 * Copyright (c) 2002, 2007, 2008, 2009 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, and by Andrew Doran.
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 1.160.2.3 2009/09/16 13:38:01 yamt Exp $");
67
68 #include "opt_compat_netbsd.h"
69 #include "opt_sock_counters.h"
70 #include "opt_sosend_loan.h"
71 #include "opt_mbuftrace.h"
72 #include "opt_somaxkva.h"
73 #include "opt_multiprocessor.h" /* XXX */
74
75 #include <sys/param.h>
76 #include <sys/systm.h>
77 #include <sys/proc.h>
78 #include <sys/file.h>
79 #include <sys/filedesc.h>
80 #include <sys/kmem.h>
81 #include <sys/mbuf.h>
82 #include <sys/domain.h>
83 #include <sys/kernel.h>
84 #include <sys/protosw.h>
85 #include <sys/socket.h>
86 #include <sys/socketvar.h>
87 #include <sys/signalvar.h>
88 #include <sys/resourcevar.h>
89 #include <sys/uidinfo.h>
90 #include <sys/event.h>
91 #include <sys/poll.h>
92 #include <sys/kauth.h>
93 #include <sys/mutex.h>
94 #include <sys/condvar.h>
95
96 #ifdef COMPAT_50
97 #include <compat/sys/time.h>
98 #include <compat/sys/socket.h>
99 #endif
100
101 #include <uvm/uvm.h>
102
103 MALLOC_DEFINE(M_SOOPTS, "soopts", "socket options");
104 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
105
106 extern const struct fileops socketops;
107
108 extern int somaxconn; /* patchable (XXX sysctl) */
109 int somaxconn = SOMAXCONN;
110 kmutex_t *softnet_lock;
111
112 #ifdef SOSEND_COUNTERS
113 #include <sys/device.h>
114
115 static struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
116 NULL, "sosend", "loan big");
117 static struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
118 NULL, "sosend", "copy big");
119 static struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
120 NULL, "sosend", "copy small");
121 static struct evcnt sosend_kvalimit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
122 NULL, "sosend", "kva limit");
123
124 #define SOSEND_COUNTER_INCR(ev) (ev)->ev_count++
125
126 EVCNT_ATTACH_STATIC(sosend_loan_big);
127 EVCNT_ATTACH_STATIC(sosend_copy_big);
128 EVCNT_ATTACH_STATIC(sosend_copy_small);
129 EVCNT_ATTACH_STATIC(sosend_kvalimit);
130 #else
131
132 #define SOSEND_COUNTER_INCR(ev) /* nothing */
133
134 #endif /* SOSEND_COUNTERS */
135
136 static struct callback_entry sokva_reclaimerentry;
137
138 #if defined(SOSEND_NO_LOAN) || defined(MULTIPROCESSOR)
139 int sock_loan_thresh = -1;
140 #else
141 int sock_loan_thresh = 4096;
142 #endif
143
144 static kmutex_t so_pendfree_lock;
145 static struct mbuf *so_pendfree;
146
147 #ifndef SOMAXKVA
148 #define SOMAXKVA (16 * 1024 * 1024)
149 #endif
150 int somaxkva = SOMAXKVA;
151 static int socurkva;
152 static kcondvar_t socurkva_cv;
153
154 #define SOCK_LOAN_CHUNK 65536
155
156 static size_t sodopendfree(void);
157 static size_t sodopendfreel(void);
158
159 static void sysctl_kern_somaxkva_setup(void);
160 static struct sysctllog *socket_sysctllog;
161
162 static vsize_t
163 sokvareserve(struct socket *so, vsize_t len)
164 {
165 int error;
166
167 mutex_enter(&so_pendfree_lock);
168 while (socurkva + len > somaxkva) {
169 size_t freed;
170
171 /*
172 * try to do pendfree.
173 */
174
175 freed = sodopendfreel();
176
177 /*
178 * if some kva was freed, try again.
179 */
180
181 if (freed)
182 continue;
183
184 SOSEND_COUNTER_INCR(&sosend_kvalimit);
185 error = cv_wait_sig(&socurkva_cv, &so_pendfree_lock);
186 if (error) {
187 len = 0;
188 break;
189 }
190 }
191 socurkva += len;
192 mutex_exit(&so_pendfree_lock);
193 return len;
194 }
195
196 static void
197 sokvaunreserve(vsize_t len)
198 {
199
200 mutex_enter(&so_pendfree_lock);
201 socurkva -= len;
202 cv_broadcast(&socurkva_cv);
203 mutex_exit(&so_pendfree_lock);
204 }
205
206 /*
207 * sokvaalloc: allocate kva for loan.
208 */
209
210 vaddr_t
211 sokvaalloc(vsize_t len, struct socket *so)
212 {
213 vaddr_t lva;
214
215 /*
216 * reserve kva.
217 */
218
219 if (sokvareserve(so, len) == 0)
220 return 0;
221
222 /*
223 * allocate kva.
224 */
225
226 lva = uvm_km_alloc(kernel_map, len, 0, UVM_KMF_VAONLY | UVM_KMF_WAITVA);
227 if (lva == 0) {
228 sokvaunreserve(len);
229 return (0);
230 }
231
232 return lva;
233 }
234
235 /*
236 * sokvafree: free kva for loan.
237 */
238
239 void
240 sokvafree(vaddr_t sva, vsize_t len)
241 {
242
243 /*
244 * free kva.
245 */
246
247 uvm_km_free(kernel_map, sva, len, UVM_KMF_VAONLY);
248
249 /*
250 * unreserve kva.
251 */
252
253 sokvaunreserve(len);
254 }
255
256 static void
257 sodoloanfree(struct vm_page **pgs, void *buf, size_t size)
258 {
259 vaddr_t sva, eva;
260 vsize_t len;
261 int npgs;
262
263 KASSERT(pgs != NULL);
264
265 eva = round_page((vaddr_t) buf + size);
266 sva = trunc_page((vaddr_t) buf);
267 len = eva - sva;
268 npgs = len >> PAGE_SHIFT;
269
270 pmap_kremove(sva, len);
271 pmap_update(pmap_kernel());
272 uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE);
273 sokvafree(sva, len);
274 }
275
276 static size_t
277 sodopendfree(void)
278 {
279 size_t rv;
280
281 if (__predict_true(so_pendfree == NULL))
282 return 0;
283
284 mutex_enter(&so_pendfree_lock);
285 rv = sodopendfreel();
286 mutex_exit(&so_pendfree_lock);
287
288 return rv;
289 }
290
291 /*
292 * sodopendfreel: free mbufs on "pendfree" list.
293 * unlock and relock so_pendfree_lock when freeing mbufs.
294 *
295 * => called with so_pendfree_lock held.
296 */
297
298 static size_t
299 sodopendfreel(void)
300 {
301 struct mbuf *m, *next;
302 size_t rv = 0;
303
304 KASSERT(mutex_owned(&so_pendfree_lock));
305
306 while (so_pendfree != NULL) {
307 m = so_pendfree;
308 so_pendfree = NULL;
309 mutex_exit(&so_pendfree_lock);
310
311 for (; m != NULL; m = next) {
312 next = m->m_next;
313 KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0);
314 KASSERT(m->m_ext.ext_refcnt == 0);
315
316 rv += m->m_ext.ext_size;
317 sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf,
318 m->m_ext.ext_size);
319 pool_cache_put(mb_cache, m);
320 }
321
322 mutex_enter(&so_pendfree_lock);
323 }
324
325 return (rv);
326 }
327
328 void
329 soloanfree(struct mbuf *m, void *buf, size_t size, void *arg)
330 {
331
332 KASSERT(m != NULL);
333
334 /*
335 * postpone freeing mbuf.
336 *
337 * we can't do it in interrupt context
338 * because we need to put kva back to kernel_map.
339 */
340
341 mutex_enter(&so_pendfree_lock);
342 m->m_next = so_pendfree;
343 so_pendfree = m;
344 cv_broadcast(&socurkva_cv);
345 mutex_exit(&so_pendfree_lock);
346 }
347
348 static long
349 sosend_loan(struct socket *so, struct uio *uio, struct mbuf *m, long space)
350 {
351 struct iovec *iov = uio->uio_iov;
352 vaddr_t sva, eva;
353 vsize_t len;
354 vaddr_t lva;
355 int npgs, error;
356 vaddr_t va;
357 int i;
358
359 if (VMSPACE_IS_KERNEL_P(uio->uio_vmspace))
360 return (0);
361
362 if (iov->iov_len < (size_t) space)
363 space = iov->iov_len;
364 if (space > SOCK_LOAN_CHUNK)
365 space = SOCK_LOAN_CHUNK;
366
367 eva = round_page((vaddr_t) iov->iov_base + space);
368 sva = trunc_page((vaddr_t) iov->iov_base);
369 len = eva - sva;
370 npgs = len >> PAGE_SHIFT;
371
372 KASSERT(npgs <= M_EXT_MAXPAGES);
373
374 lva = sokvaalloc(len, so);
375 if (lva == 0)
376 return 0;
377
378 error = uvm_loan(&uio->uio_vmspace->vm_map, sva, len,
379 m->m_ext.ext_pgs, UVM_LOAN_TOPAGE);
380 if (error) {
381 sokvafree(lva, len);
382 return (0);
383 }
384
385 for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE)
386 pmap_kenter_pa(va, VM_PAGE_TO_PHYS(m->m_ext.ext_pgs[i]),
387 VM_PROT_READ);
388 pmap_update(pmap_kernel());
389
390 lva += (vaddr_t) iov->iov_base & PAGE_MASK;
391
392 MEXTADD(m, (void *) lva, space, M_MBUF, soloanfree, so);
393 m->m_flags |= M_EXT_PAGES | M_EXT_ROMAP;
394
395 uio->uio_resid -= space;
396 /* uio_offset not updated, not set/used for write(2) */
397 uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + space;
398 uio->uio_iov->iov_len -= space;
399 if (uio->uio_iov->iov_len == 0) {
400 uio->uio_iov++;
401 uio->uio_iovcnt--;
402 }
403
404 return (space);
405 }
406
407 static int
408 sokva_reclaim_callback(struct callback_entry *ce, void *obj, void *arg)
409 {
410
411 KASSERT(ce == &sokva_reclaimerentry);
412 KASSERT(obj == NULL);
413
414 sodopendfree();
415 if (!vm_map_starved_p(kernel_map)) {
416 return CALLBACK_CHAIN_ABORT;
417 }
418 return CALLBACK_CHAIN_CONTINUE;
419 }
420
421 struct mbuf *
422 getsombuf(struct socket *so, int type)
423 {
424 struct mbuf *m;
425
426 m = m_get(M_WAIT, type);
427 MCLAIM(m, so->so_mowner);
428 return m;
429 }
430
431 void
432 soinit(void)
433 {
434
435 sysctl_kern_somaxkva_setup();
436
437 mutex_init(&so_pendfree_lock, MUTEX_DEFAULT, IPL_VM);
438 softnet_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
439 cv_init(&socurkva_cv, "sokva");
440 soinit2();
441
442 /* Set the initial adjusted socket buffer size. */
443 if (sb_max_set(sb_max))
444 panic("bad initial sb_max value: %lu", sb_max);
445
446 callback_register(&vm_map_to_kernel(kernel_map)->vmk_reclaim_callback,
447 &sokva_reclaimerentry, NULL, sokva_reclaim_callback);
448 }
449
450 /*
451 * Socket operation routines.
452 * These routines are called by the routines in
453 * sys_socket.c or from a system process, and
454 * implement the semantics of socket operations by
455 * switching out to the protocol specific routines.
456 */
457 /*ARGSUSED*/
458 int
459 socreate(int dom, struct socket **aso, int type, int proto, struct lwp *l,
460 struct socket *lockso)
461 {
462 const struct protosw *prp;
463 struct socket *so;
464 uid_t uid;
465 int error;
466 kmutex_t *lock;
467
468 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET,
469 KAUTH_REQ_NETWORK_SOCKET_OPEN, KAUTH_ARG(dom), KAUTH_ARG(type),
470 KAUTH_ARG(proto));
471 if (error != 0)
472 return error;
473
474 if (proto)
475 prp = pffindproto(dom, proto, type);
476 else
477 prp = pffindtype(dom, type);
478 if (prp == NULL) {
479 /* no support for domain */
480 if (pffinddomain(dom) == 0)
481 return EAFNOSUPPORT;
482 /* no support for socket type */
483 if (proto == 0 && type != 0)
484 return EPROTOTYPE;
485 return EPROTONOSUPPORT;
486 }
487 if (prp->pr_usrreq == NULL)
488 return EPROTONOSUPPORT;
489 if (prp->pr_type != type)
490 return EPROTOTYPE;
491
492 so = soget(true);
493 so->so_type = type;
494 so->so_proto = prp;
495 so->so_send = sosend;
496 so->so_receive = soreceive;
497 #ifdef MBUFTRACE
498 so->so_rcv.sb_mowner = &prp->pr_domain->dom_mowner;
499 so->so_snd.sb_mowner = &prp->pr_domain->dom_mowner;
500 so->so_mowner = &prp->pr_domain->dom_mowner;
501 #endif
502 uid = kauth_cred_geteuid(l->l_cred);
503 so->so_uidinfo = uid_find(uid);
504 so->so_egid = kauth_cred_getegid(l->l_cred);
505 so->so_cpid = l->l_proc->p_pid;
506 if (lockso != NULL) {
507 /* Caller wants us to share a lock. */
508 lock = lockso->so_lock;
509 so->so_lock = lock;
510 mutex_obj_hold(lock);
511 mutex_enter(lock);
512 } else {
513 /* Lock assigned and taken during PRU_ATTACH. */
514 }
515 error = (*prp->pr_usrreq)(so, PRU_ATTACH, NULL,
516 (struct mbuf *)(long)proto, NULL, l);
517 KASSERT(solocked(so));
518 if (error != 0) {
519 so->so_state |= SS_NOFDREF;
520 sofree(so);
521 return error;
522 }
523 sounlock(so);
524 *aso = so;
525 return 0;
526 }
527
528 /* On success, write file descriptor to fdout and return zero. On
529 * failure, return non-zero; *fdout will be undefined.
530 */
531 int
532 fsocreate(int domain, struct socket **sop, int type, int protocol,
533 struct lwp *l, int *fdout)
534 {
535 struct socket *so;
536 struct file *fp;
537 int fd, error;
538
539 if ((error = fd_allocfile(&fp, &fd)) != 0)
540 return (error);
541 fp->f_flag = FREAD|FWRITE;
542 fp->f_type = DTYPE_SOCKET;
543 fp->f_ops = &socketops;
544 error = socreate(domain, &so, type, protocol, l, NULL);
545 if (error != 0) {
546 fd_abort(curproc, fp, fd);
547 } else {
548 if (sop != NULL)
549 *sop = so;
550 fp->f_data = so;
551 fd_affix(curproc, fp, fd);
552 *fdout = fd;
553 }
554 return error;
555 }
556
557 int
558 sofamily(const struct socket *so)
559 {
560 const struct protosw *pr;
561 const struct domain *dom;
562
563 if ((pr = so->so_proto) == NULL)
564 return AF_UNSPEC;
565 if ((dom = pr->pr_domain) == NULL)
566 return AF_UNSPEC;
567 return dom->dom_family;
568 }
569
570 int
571 sobind(struct socket *so, struct mbuf *nam, struct lwp *l)
572 {
573 int error;
574
575 solock(so);
576 error = (*so->so_proto->pr_usrreq)(so, PRU_BIND, NULL, nam, NULL, l);
577 sounlock(so);
578 return error;
579 }
580
581 int
582 solisten(struct socket *so, int backlog, struct lwp *l)
583 {
584 int error;
585
586 solock(so);
587 if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
588 SS_ISDISCONNECTING)) != 0) {
589 sounlock(so);
590 return (EOPNOTSUPP);
591 }
592 error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, NULL,
593 NULL, NULL, l);
594 if (error != 0) {
595 sounlock(so);
596 return error;
597 }
598 if (TAILQ_EMPTY(&so->so_q))
599 so->so_options |= SO_ACCEPTCONN;
600 if (backlog < 0)
601 backlog = 0;
602 so->so_qlimit = min(backlog, somaxconn);
603 sounlock(so);
604 return 0;
605 }
606
607 void
608 sofree(struct socket *so)
609 {
610 u_int refs;
611
612 KASSERT(solocked(so));
613
614 if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) {
615 sounlock(so);
616 return;
617 }
618 if (so->so_head) {
619 /*
620 * We must not decommission a socket that's on the accept(2)
621 * queue. If we do, then accept(2) may hang after select(2)
622 * indicated that the listening socket was ready.
623 */
624 if (!soqremque(so, 0)) {
625 sounlock(so);
626 return;
627 }
628 }
629 if (so->so_rcv.sb_hiwat)
630 (void)chgsbsize(so->so_uidinfo, &so->so_rcv.sb_hiwat, 0,
631 RLIM_INFINITY);
632 if (so->so_snd.sb_hiwat)
633 (void)chgsbsize(so->so_uidinfo, &so->so_snd.sb_hiwat, 0,
634 RLIM_INFINITY);
635 sbrelease(&so->so_snd, so);
636 KASSERT(!cv_has_waiters(&so->so_cv));
637 KASSERT(!cv_has_waiters(&so->so_rcv.sb_cv));
638 KASSERT(!cv_has_waiters(&so->so_snd.sb_cv));
639 sorflush(so);
640 refs = so->so_aborting; /* XXX */
641 /* Remove acccept filter if one is present. */
642 if (so->so_accf != NULL)
643 (void)accept_filt_clear(so);
644 sounlock(so);
645 if (refs == 0) /* XXX */
646 soput(so);
647 }
648
649 /*
650 * Close a socket on last file table reference removal.
651 * Initiate disconnect if connected.
652 * Free socket when disconnect complete.
653 */
654 int
655 soclose(struct socket *so)
656 {
657 struct socket *so2;
658 int error;
659 int error2;
660
661 error = 0;
662 solock(so);
663 if (so->so_options & SO_ACCEPTCONN) {
664 for (;;) {
665 if ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) {
666 KASSERT(solocked2(so, so2));
667 (void) soqremque(so2, 0);
668 /* soabort drops the lock. */
669 (void) soabort(so2);
670 solock(so);
671 continue;
672 }
673 if ((so2 = TAILQ_FIRST(&so->so_q)) != 0) {
674 KASSERT(solocked2(so, so2));
675 (void) soqremque(so2, 1);
676 /* soabort drops the lock. */
677 (void) soabort(so2);
678 solock(so);
679 continue;
680 }
681 break;
682 }
683 }
684 if (so->so_pcb == 0)
685 goto discard;
686 if (so->so_state & SS_ISCONNECTED) {
687 if ((so->so_state & SS_ISDISCONNECTING) == 0) {
688 error = sodisconnect(so);
689 if (error)
690 goto drop;
691 }
692 if (so->so_options & SO_LINGER) {
693 if ((so->so_state & SS_ISDISCONNECTING) && so->so_nbio)
694 goto drop;
695 while (so->so_state & SS_ISCONNECTED) {
696 error = sowait(so, true, so->so_linger * hz);
697 if (error)
698 break;
699 }
700 }
701 }
702 drop:
703 if (so->so_pcb) {
704 error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH,
705 NULL, NULL, NULL, NULL);
706 if (error == 0)
707 error = error2;
708 }
709 discard:
710 if (so->so_state & SS_NOFDREF)
711 panic("soclose: NOFDREF");
712 so->so_state |= SS_NOFDREF;
713 sofree(so);
714 return (error);
715 }
716
717 /*
718 * Must be called with the socket locked.. Will return with it unlocked.
719 */
720 int
721 soabort(struct socket *so)
722 {
723 u_int refs;
724 int error;
725
726 KASSERT(solocked(so));
727 KASSERT(so->so_head == NULL);
728
729 so->so_aborting++; /* XXX */
730 error = (*so->so_proto->pr_usrreq)(so, PRU_ABORT, NULL,
731 NULL, NULL, NULL);
732 refs = --so->so_aborting; /* XXX */
733 if (error || (refs == 0)) {
734 sofree(so);
735 } else {
736 sounlock(so);
737 }
738 return error;
739 }
740
741 int
742 soaccept(struct socket *so, struct mbuf *nam)
743 {
744 int error;
745
746 KASSERT(solocked(so));
747
748 error = 0;
749 if ((so->so_state & SS_NOFDREF) == 0)
750 panic("soaccept: !NOFDREF");
751 so->so_state &= ~SS_NOFDREF;
752 if ((so->so_state & SS_ISDISCONNECTED) == 0 ||
753 (so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0)
754 error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT,
755 NULL, nam, NULL, NULL);
756 else
757 error = ECONNABORTED;
758
759 return (error);
760 }
761
762 int
763 soconnect(struct socket *so, struct mbuf *nam, struct lwp *l)
764 {
765 int error;
766
767 KASSERT(solocked(so));
768
769 if (so->so_options & SO_ACCEPTCONN)
770 return (EOPNOTSUPP);
771 /*
772 * If protocol is connection-based, can only connect once.
773 * Otherwise, if connected, try to disconnect first.
774 * This allows user to disconnect by connecting to, e.g.,
775 * a null address.
776 */
777 if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
778 ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
779 (error = sodisconnect(so))))
780 error = EISCONN;
781 else
782 error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT,
783 NULL, nam, NULL, l);
784 return (error);
785 }
786
787 int
788 soconnect2(struct socket *so1, struct socket *so2)
789 {
790 int error;
791
792 KASSERT(solocked2(so1, so2));
793
794 error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2,
795 NULL, (struct mbuf *)so2, NULL, NULL);
796 return (error);
797 }
798
799 int
800 sodisconnect(struct socket *so)
801 {
802 int error;
803
804 KASSERT(solocked(so));
805
806 if ((so->so_state & SS_ISCONNECTED) == 0) {
807 error = ENOTCONN;
808 } else if (so->so_state & SS_ISDISCONNECTING) {
809 error = EALREADY;
810 } else {
811 error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT,
812 NULL, NULL, NULL, NULL);
813 }
814 sodopendfree();
815 return (error);
816 }
817
818 #define SBLOCKWAIT(f) (((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
819 /*
820 * Send on a socket.
821 * If send must go all at once and message is larger than
822 * send buffering, then hard error.
823 * Lock against other senders.
824 * If must go all at once and not enough room now, then
825 * inform user that this would block and do nothing.
826 * Otherwise, if nonblocking, send as much as possible.
827 * The data to be sent is described by "uio" if nonzero,
828 * otherwise by the mbuf chain "top" (which must be null
829 * if uio is not). Data provided in mbuf chain must be small
830 * enough to send all at once.
831 *
832 * Returns nonzero on error, timeout or signal; callers
833 * must check for short counts if EINTR/ERESTART are returned.
834 * Data and control buffers are freed on return.
835 */
836 int
837 sosend(struct socket *so, struct mbuf *addr, struct uio *uio, struct mbuf *top,
838 struct mbuf *control, int flags, struct lwp *l)
839 {
840 struct mbuf **mp, *m;
841 struct proc *p;
842 long space, len, resid, clen, mlen;
843 int error, s, dontroute, atomic;
844
845 p = l->l_proc;
846 sodopendfree();
847 clen = 0;
848
849 /*
850 * solock() provides atomicity of access. splsoftnet() prevents
851 * protocol processing soft interrupts from interrupting us and
852 * blocking (expensive).
853 */
854 s = splsoftnet();
855 solock(so);
856 atomic = sosendallatonce(so) || top;
857 if (uio)
858 resid = uio->uio_resid;
859 else
860 resid = top->m_pkthdr.len;
861 /*
862 * In theory resid should be unsigned.
863 * However, space must be signed, as it might be less than 0
864 * if we over-committed, and we must use a signed comparison
865 * of space and resid. On the other hand, a negative resid
866 * causes us to loop sending 0-length segments to the protocol.
867 */
868 if (resid < 0) {
869 error = EINVAL;
870 goto out;
871 }
872 dontroute =
873 (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
874 (so->so_proto->pr_flags & PR_ATOMIC);
875 l->l_ru.ru_msgsnd++;
876 if (control)
877 clen = control->m_len;
878 restart:
879 if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0)
880 goto out;
881 do {
882 if (so->so_state & SS_CANTSENDMORE) {
883 error = EPIPE;
884 goto release;
885 }
886 if (so->so_error) {
887 error = so->so_error;
888 so->so_error = 0;
889 goto release;
890 }
891 if ((so->so_state & SS_ISCONNECTED) == 0) {
892 if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
893 if ((so->so_state & SS_ISCONFIRMING) == 0 &&
894 !(resid == 0 && clen != 0)) {
895 error = ENOTCONN;
896 goto release;
897 }
898 } else if (addr == 0) {
899 error = EDESTADDRREQ;
900 goto release;
901 }
902 }
903 space = sbspace(&so->so_snd);
904 if (flags & MSG_OOB)
905 space += 1024;
906 if ((atomic && resid > so->so_snd.sb_hiwat) ||
907 clen > so->so_snd.sb_hiwat) {
908 error = EMSGSIZE;
909 goto release;
910 }
911 if (space < resid + clen &&
912 (atomic || space < so->so_snd.sb_lowat || space < clen)) {
913 if (so->so_nbio) {
914 error = EWOULDBLOCK;
915 goto release;
916 }
917 sbunlock(&so->so_snd);
918 error = sbwait(&so->so_snd);
919 if (error)
920 goto out;
921 goto restart;
922 }
923 mp = ⊤
924 space -= clen;
925 do {
926 if (uio == NULL) {
927 /*
928 * Data is prepackaged in "top".
929 */
930 resid = 0;
931 if (flags & MSG_EOR)
932 top->m_flags |= M_EOR;
933 } else do {
934 sounlock(so);
935 splx(s);
936 if (top == NULL) {
937 m = m_gethdr(M_WAIT, MT_DATA);
938 mlen = MHLEN;
939 m->m_pkthdr.len = 0;
940 m->m_pkthdr.rcvif = NULL;
941 } else {
942 m = m_get(M_WAIT, MT_DATA);
943 mlen = MLEN;
944 }
945 MCLAIM(m, so->so_snd.sb_mowner);
946 if (sock_loan_thresh >= 0 &&
947 uio->uio_iov->iov_len >= sock_loan_thresh &&
948 space >= sock_loan_thresh &&
949 (len = sosend_loan(so, uio, m,
950 space)) != 0) {
951 SOSEND_COUNTER_INCR(&sosend_loan_big);
952 space -= len;
953 goto have_data;
954 }
955 if (resid >= MINCLSIZE && space >= MCLBYTES) {
956 SOSEND_COUNTER_INCR(&sosend_copy_big);
957 m_clget(m, M_WAIT);
958 if ((m->m_flags & M_EXT) == 0)
959 goto nopages;
960 mlen = MCLBYTES;
961 if (atomic && top == 0) {
962 len = lmin(MCLBYTES - max_hdr,
963 resid);
964 m->m_data += max_hdr;
965 } else
966 len = lmin(MCLBYTES, resid);
967 space -= len;
968 } else {
969 nopages:
970 SOSEND_COUNTER_INCR(&sosend_copy_small);
971 len = lmin(lmin(mlen, resid), space);
972 space -= len;
973 /*
974 * For datagram protocols, leave room
975 * for protocol headers in first mbuf.
976 */
977 if (atomic && top == 0 && len < mlen)
978 MH_ALIGN(m, len);
979 }
980 error = uiomove(mtod(m, void *), (int)len, uio);
981 have_data:
982 resid = uio->uio_resid;
983 m->m_len = len;
984 *mp = m;
985 top->m_pkthdr.len += len;
986 s = splsoftnet();
987 solock(so);
988 if (error != 0)
989 goto release;
990 mp = &m->m_next;
991 if (resid <= 0) {
992 if (flags & MSG_EOR)
993 top->m_flags |= M_EOR;
994 break;
995 }
996 } while (space > 0 && atomic);
997
998 if (so->so_state & SS_CANTSENDMORE) {
999 error = EPIPE;
1000 goto release;
1001 }
1002 if (dontroute)
1003 so->so_options |= SO_DONTROUTE;
1004 if (resid > 0)
1005 so->so_state |= SS_MORETOCOME;
1006 error = (*so->so_proto->pr_usrreq)(so,
1007 (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND,
1008 top, addr, control, curlwp);
1009 if (dontroute)
1010 so->so_options &= ~SO_DONTROUTE;
1011 if (resid > 0)
1012 so->so_state &= ~SS_MORETOCOME;
1013 clen = 0;
1014 control = NULL;
1015 top = NULL;
1016 mp = ⊤
1017 if (error != 0)
1018 goto release;
1019 } while (resid && space > 0);
1020 } while (resid);
1021
1022 release:
1023 sbunlock(&so->so_snd);
1024 out:
1025 sounlock(so);
1026 splx(s);
1027 if (top)
1028 m_freem(top);
1029 if (control)
1030 m_freem(control);
1031 return (error);
1032 }
1033
1034 /*
1035 * Following replacement or removal of the first mbuf on the first
1036 * mbuf chain of a socket buffer, push necessary state changes back
1037 * into the socket buffer so that other consumers see the values
1038 * consistently. 'nextrecord' is the callers locally stored value of
1039 * the original value of sb->sb_mb->m_nextpkt which must be restored
1040 * when the lead mbuf changes. NOTE: 'nextrecord' may be NULL.
1041 */
1042 static void
1043 sbsync(struct sockbuf *sb, struct mbuf *nextrecord)
1044 {
1045
1046 KASSERT(solocked(sb->sb_so));
1047
1048 /*
1049 * First, update for the new value of nextrecord. If necessary,
1050 * make it the first record.
1051 */
1052 if (sb->sb_mb != NULL)
1053 sb->sb_mb->m_nextpkt = nextrecord;
1054 else
1055 sb->sb_mb = nextrecord;
1056
1057 /*
1058 * Now update any dependent socket buffer fields to reflect
1059 * the new state. This is an inline of SB_EMPTY_FIXUP, with
1060 * the addition of a second clause that takes care of the
1061 * case where sb_mb has been updated, but remains the last
1062 * record.
1063 */
1064 if (sb->sb_mb == NULL) {
1065 sb->sb_mbtail = NULL;
1066 sb->sb_lastrecord = NULL;
1067 } else if (sb->sb_mb->m_nextpkt == NULL)
1068 sb->sb_lastrecord = sb->sb_mb;
1069 }
1070
1071 /*
1072 * Implement receive operations on a socket.
1073 * We depend on the way that records are added to the sockbuf
1074 * by sbappend*. In particular, each record (mbufs linked through m_next)
1075 * must begin with an address if the protocol so specifies,
1076 * followed by an optional mbuf or mbufs containing ancillary data,
1077 * and then zero or more mbufs of data.
1078 * In order to avoid blocking network interrupts for the entire time here,
1079 * we splx() while doing the actual copy to user space.
1080 * Although the sockbuf is locked, new data may still be appended,
1081 * and thus we must maintain consistency of the sockbuf during that time.
1082 *
1083 * The caller may receive the data as a single mbuf chain by supplying
1084 * an mbuf **mp0 for use in returning the chain. The uio is then used
1085 * only for the count in uio_resid.
1086 */
1087 int
1088 soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio,
1089 struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
1090 {
1091 struct lwp *l = curlwp;
1092 struct mbuf *m, **mp, *mt;
1093 int atomic, flags, len, error, s, offset, moff, type, orig_resid;
1094 const struct protosw *pr;
1095 struct mbuf *nextrecord;
1096 int mbuf_removed = 0;
1097 const struct domain *dom;
1098
1099 pr = so->so_proto;
1100 atomic = pr->pr_flags & PR_ATOMIC;
1101 dom = pr->pr_domain;
1102 mp = mp0;
1103 type = 0;
1104 orig_resid = uio->uio_resid;
1105
1106 if (paddr != NULL)
1107 *paddr = NULL;
1108 if (controlp != NULL)
1109 *controlp = NULL;
1110 if (flagsp != NULL)
1111 flags = *flagsp &~ MSG_EOR;
1112 else
1113 flags = 0;
1114
1115 if ((flags & MSG_DONTWAIT) == 0)
1116 sodopendfree();
1117
1118 if (flags & MSG_OOB) {
1119 m = m_get(M_WAIT, MT_DATA);
1120 solock(so);
1121 error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m,
1122 (struct mbuf *)(long)(flags & MSG_PEEK), NULL, l);
1123 sounlock(so);
1124 if (error)
1125 goto bad;
1126 do {
1127 error = uiomove(mtod(m, void *),
1128 (int) min(uio->uio_resid, m->m_len), uio);
1129 m = m_free(m);
1130 } while (uio->uio_resid > 0 && error == 0 && m);
1131 bad:
1132 if (m != NULL)
1133 m_freem(m);
1134 return error;
1135 }
1136 if (mp != NULL)
1137 *mp = NULL;
1138
1139 /*
1140 * solock() provides atomicity of access. splsoftnet() prevents
1141 * protocol processing soft interrupts from interrupting us and
1142 * blocking (expensive).
1143 */
1144 s = splsoftnet();
1145 solock(so);
1146 if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
1147 (*pr->pr_usrreq)(so, PRU_RCVD, NULL, NULL, NULL, l);
1148
1149 restart:
1150 if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) {
1151 sounlock(so);
1152 splx(s);
1153 return error;
1154 }
1155
1156 m = so->so_rcv.sb_mb;
1157 /*
1158 * If we have less data than requested, block awaiting more
1159 * (subject to any timeout) if:
1160 * 1. the current count is less than the low water mark,
1161 * 2. MSG_WAITALL is set, and it is possible to do the entire
1162 * receive operation at once if we block (resid <= hiwat), or
1163 * 3. MSG_DONTWAIT is not set.
1164 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1165 * we have to do the receive in sections, and thus risk returning
1166 * a short count if a timeout or signal occurs after we start.
1167 */
1168 if (m == NULL ||
1169 ((flags & MSG_DONTWAIT) == 0 &&
1170 so->so_rcv.sb_cc < uio->uio_resid &&
1171 (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
1172 ((flags & MSG_WAITALL) &&
1173 uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
1174 m->m_nextpkt == NULL && !atomic)) {
1175 #ifdef DIAGNOSTIC
1176 if (m == NULL && so->so_rcv.sb_cc)
1177 panic("receive 1");
1178 #endif
1179 if (so->so_error) {
1180 if (m != NULL)
1181 goto dontblock;
1182 error = so->so_error;
1183 if ((flags & MSG_PEEK) == 0)
1184 so->so_error = 0;
1185 goto release;
1186 }
1187 if (so->so_state & SS_CANTRCVMORE) {
1188 if (m != NULL)
1189 goto dontblock;
1190 else
1191 goto release;
1192 }
1193 for (; m != NULL; m = m->m_next)
1194 if (m->m_type == MT_OOBDATA || (m->m_flags & M_EOR)) {
1195 m = so->so_rcv.sb_mb;
1196 goto dontblock;
1197 }
1198 if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1199 (so->so_proto->pr_flags & PR_CONNREQUIRED)) {
1200 error = ENOTCONN;
1201 goto release;
1202 }
1203 if (uio->uio_resid == 0)
1204 goto release;
1205 if (so->so_nbio || (flags & MSG_DONTWAIT)) {
1206 error = EWOULDBLOCK;
1207 goto release;
1208 }
1209 SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1");
1210 SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1");
1211 sbunlock(&so->so_rcv);
1212 error = sbwait(&so->so_rcv);
1213 if (error != 0) {
1214 sounlock(so);
1215 splx(s);
1216 return error;
1217 }
1218 goto restart;
1219 }
1220 dontblock:
1221 /*
1222 * On entry here, m points to the first record of the socket buffer.
1223 * From this point onward, we maintain 'nextrecord' as a cache of the
1224 * pointer to the next record in the socket buffer. We must keep the
1225 * various socket buffer pointers and local stack versions of the
1226 * pointers in sync, pushing out modifications before dropping the
1227 * socket lock, and re-reading them when picking it up.
1228 *
1229 * Otherwise, we will race with the network stack appending new data
1230 * or records onto the socket buffer by using inconsistent/stale
1231 * versions of the field, possibly resulting in socket buffer
1232 * corruption.
1233 *
1234 * By holding the high-level sblock(), we prevent simultaneous
1235 * readers from pulling off the front of the socket buffer.
1236 */
1237 if (l != NULL)
1238 l->l_ru.ru_msgrcv++;
1239 KASSERT(m == so->so_rcv.sb_mb);
1240 SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
1241 SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
1242 nextrecord = m->m_nextpkt;
1243 if (pr->pr_flags & PR_ADDR) {
1244 #ifdef DIAGNOSTIC
1245 if (m->m_type != MT_SONAME)
1246 panic("receive 1a");
1247 #endif
1248 orig_resid = 0;
1249 if (flags & MSG_PEEK) {
1250 if (paddr)
1251 *paddr = m_copy(m, 0, m->m_len);
1252 m = m->m_next;
1253 } else {
1254 sbfree(&so->so_rcv, m);
1255 mbuf_removed = 1;
1256 if (paddr != NULL) {
1257 *paddr = m;
1258 so->so_rcv.sb_mb = m->m_next;
1259 m->m_next = NULL;
1260 m = so->so_rcv.sb_mb;
1261 } else {
1262 MFREE(m, so->so_rcv.sb_mb);
1263 m = so->so_rcv.sb_mb;
1264 }
1265 sbsync(&so->so_rcv, nextrecord);
1266 }
1267 }
1268
1269 /*
1270 * Process one or more MT_CONTROL mbufs present before any data mbufs
1271 * in the first mbuf chain on the socket buffer. If MSG_PEEK, we
1272 * just copy the data; if !MSG_PEEK, we call into the protocol to
1273 * perform externalization (or freeing if controlp == NULL).
1274 */
1275 if (__predict_false(m != NULL && m->m_type == MT_CONTROL)) {
1276 struct mbuf *cm = NULL, *cmn;
1277 struct mbuf **cme = &cm;
1278
1279 do {
1280 if (flags & MSG_PEEK) {
1281 if (controlp != NULL) {
1282 *controlp = m_copy(m, 0, m->m_len);
1283 controlp = &(*controlp)->m_next;
1284 }
1285 m = m->m_next;
1286 } else {
1287 sbfree(&so->so_rcv, m);
1288 so->so_rcv.sb_mb = m->m_next;
1289 m->m_next = NULL;
1290 *cme = m;
1291 cme = &(*cme)->m_next;
1292 m = so->so_rcv.sb_mb;
1293 }
1294 } while (m != NULL && m->m_type == MT_CONTROL);
1295 if ((flags & MSG_PEEK) == 0)
1296 sbsync(&so->so_rcv, nextrecord);
1297 for (; cm != NULL; cm = cmn) {
1298 cmn = cm->m_next;
1299 cm->m_next = NULL;
1300 type = mtod(cm, struct cmsghdr *)->cmsg_type;
1301 if (controlp != NULL) {
1302 if (dom->dom_externalize != NULL &&
1303 type == SCM_RIGHTS) {
1304 sounlock(so);
1305 splx(s);
1306 error = (*dom->dom_externalize)(cm, l);
1307 s = splsoftnet();
1308 solock(so);
1309 }
1310 *controlp = cm;
1311 while (*controlp != NULL)
1312 controlp = &(*controlp)->m_next;
1313 } else {
1314 /*
1315 * Dispose of any SCM_RIGHTS message that went
1316 * through the read path rather than recv.
1317 */
1318 if (dom->dom_dispose != NULL &&
1319 type == SCM_RIGHTS) {
1320 sounlock(so);
1321 (*dom->dom_dispose)(cm);
1322 solock(so);
1323 }
1324 m_freem(cm);
1325 }
1326 }
1327 if (m != NULL)
1328 nextrecord = so->so_rcv.sb_mb->m_nextpkt;
1329 else
1330 nextrecord = so->so_rcv.sb_mb;
1331 orig_resid = 0;
1332 }
1333
1334 /* If m is non-NULL, we have some data to read. */
1335 if (__predict_true(m != NULL)) {
1336 type = m->m_type;
1337 if (type == MT_OOBDATA)
1338 flags |= MSG_OOB;
1339 }
1340 SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
1341 SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
1342
1343 moff = 0;
1344 offset = 0;
1345 while (m != NULL && uio->uio_resid > 0 && error == 0) {
1346 if (m->m_type == MT_OOBDATA) {
1347 if (type != MT_OOBDATA)
1348 break;
1349 } else if (type == MT_OOBDATA)
1350 break;
1351 #ifdef DIAGNOSTIC
1352 else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
1353 panic("receive 3");
1354 #endif
1355 so->so_state &= ~SS_RCVATMARK;
1356 len = uio->uio_resid;
1357 if (so->so_oobmark && len > so->so_oobmark - offset)
1358 len = so->so_oobmark - offset;
1359 if (len > m->m_len - moff)
1360 len = m->m_len - moff;
1361 /*
1362 * If mp is set, just pass back the mbufs.
1363 * Otherwise copy them out via the uio, then free.
1364 * Sockbuf must be consistent here (points to current mbuf,
1365 * it points to next record) when we drop priority;
1366 * we must note any additions to the sockbuf when we
1367 * block interrupts again.
1368 */
1369 if (mp == NULL) {
1370 SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove");
1371 SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove");
1372 sounlock(so);
1373 splx(s);
1374 error = uiomove(mtod(m, char *) + moff, (int)len, uio);
1375 s = splsoftnet();
1376 solock(so);
1377 if (error != 0) {
1378 /*
1379 * If any part of the record has been removed
1380 * (such as the MT_SONAME mbuf, which will
1381 * happen when PR_ADDR, and thus also
1382 * PR_ATOMIC, is set), then drop the entire
1383 * record to maintain the atomicity of the
1384 * receive operation.
1385 *
1386 * This avoids a later panic("receive 1a")
1387 * when compiled with DIAGNOSTIC.
1388 */
1389 if (m && mbuf_removed && atomic)
1390 (void) sbdroprecord(&so->so_rcv);
1391
1392 goto release;
1393 }
1394 } else
1395 uio->uio_resid -= len;
1396 if (len == m->m_len - moff) {
1397 if (m->m_flags & M_EOR)
1398 flags |= MSG_EOR;
1399 if (flags & MSG_PEEK) {
1400 m = m->m_next;
1401 moff = 0;
1402 } else {
1403 nextrecord = m->m_nextpkt;
1404 sbfree(&so->so_rcv, m);
1405 if (mp) {
1406 *mp = m;
1407 mp = &m->m_next;
1408 so->so_rcv.sb_mb = m = m->m_next;
1409 *mp = NULL;
1410 } else {
1411 MFREE(m, so->so_rcv.sb_mb);
1412 m = so->so_rcv.sb_mb;
1413 }
1414 /*
1415 * If m != NULL, we also know that
1416 * so->so_rcv.sb_mb != NULL.
1417 */
1418 KASSERT(so->so_rcv.sb_mb == m);
1419 if (m) {
1420 m->m_nextpkt = nextrecord;
1421 if (nextrecord == NULL)
1422 so->so_rcv.sb_lastrecord = m;
1423 } else {
1424 so->so_rcv.sb_mb = nextrecord;
1425 SB_EMPTY_FIXUP(&so->so_rcv);
1426 }
1427 SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
1428 SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
1429 }
1430 } else if (flags & MSG_PEEK)
1431 moff += len;
1432 else {
1433 if (mp != NULL) {
1434 mt = m_copym(m, 0, len, M_NOWAIT);
1435 if (__predict_false(mt == NULL)) {
1436 sounlock(so);
1437 mt = m_copym(m, 0, len, M_WAIT);
1438 solock(so);
1439 }
1440 *mp = mt;
1441 }
1442 m->m_data += len;
1443 m->m_len -= len;
1444 so->so_rcv.sb_cc -= len;
1445 }
1446 if (so->so_oobmark) {
1447 if ((flags & MSG_PEEK) == 0) {
1448 so->so_oobmark -= len;
1449 if (so->so_oobmark == 0) {
1450 so->so_state |= SS_RCVATMARK;
1451 break;
1452 }
1453 } else {
1454 offset += len;
1455 if (offset == so->so_oobmark)
1456 break;
1457 }
1458 }
1459 if (flags & MSG_EOR)
1460 break;
1461 /*
1462 * If the MSG_WAITALL flag is set (for non-atomic socket),
1463 * we must not quit until "uio->uio_resid == 0" or an error
1464 * termination. If a signal/timeout occurs, return
1465 * with a short count but without error.
1466 * Keep sockbuf locked against other readers.
1467 */
1468 while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
1469 !sosendallatonce(so) && !nextrecord) {
1470 if (so->so_error || so->so_state & SS_CANTRCVMORE)
1471 break;
1472 /*
1473 * If we are peeking and the socket receive buffer is
1474 * full, stop since we can't get more data to peek at.
1475 */
1476 if ((flags & MSG_PEEK) && sbspace(&so->so_rcv) <= 0)
1477 break;
1478 /*
1479 * If we've drained the socket buffer, tell the
1480 * protocol in case it needs to do something to
1481 * get it filled again.
1482 */
1483 if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb)
1484 (*pr->pr_usrreq)(so, PRU_RCVD,
1485 NULL, (struct mbuf *)(long)flags, NULL, l);
1486 SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2");
1487 SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2");
1488 error = sbwait(&so->so_rcv);
1489 if (error != 0) {
1490 sbunlock(&so->so_rcv);
1491 sounlock(so);
1492 splx(s);
1493 return 0;
1494 }
1495 if ((m = so->so_rcv.sb_mb) != NULL)
1496 nextrecord = m->m_nextpkt;
1497 }
1498 }
1499
1500 if (m && atomic) {
1501 flags |= MSG_TRUNC;
1502 if ((flags & MSG_PEEK) == 0)
1503 (void) sbdroprecord(&so->so_rcv);
1504 }
1505 if ((flags & MSG_PEEK) == 0) {
1506 if (m == NULL) {
1507 /*
1508 * First part is an inline SB_EMPTY_FIXUP(). Second
1509 * part makes sure sb_lastrecord is up-to-date if
1510 * there is still data in the socket buffer.
1511 */
1512 so->so_rcv.sb_mb = nextrecord;
1513 if (so->so_rcv.sb_mb == NULL) {
1514 so->so_rcv.sb_mbtail = NULL;
1515 so->so_rcv.sb_lastrecord = NULL;
1516 } else if (nextrecord->m_nextpkt == NULL)
1517 so->so_rcv.sb_lastrecord = nextrecord;
1518 }
1519 SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
1520 SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
1521 if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1522 (*pr->pr_usrreq)(so, PRU_RCVD, NULL,
1523 (struct mbuf *)(long)flags, NULL, l);
1524 }
1525 if (orig_resid == uio->uio_resid && orig_resid &&
1526 (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
1527 sbunlock(&so->so_rcv);
1528 goto restart;
1529 }
1530
1531 if (flagsp != NULL)
1532 *flagsp |= flags;
1533 release:
1534 sbunlock(&so->so_rcv);
1535 sounlock(so);
1536 splx(s);
1537 return error;
1538 }
1539
1540 int
1541 soshutdown(struct socket *so, int how)
1542 {
1543 const struct protosw *pr;
1544 int error;
1545
1546 KASSERT(solocked(so));
1547
1548 pr = so->so_proto;
1549 if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
1550 return (EINVAL);
1551
1552 if (how == SHUT_RD || how == SHUT_RDWR) {
1553 sorflush(so);
1554 error = 0;
1555 }
1556 if (how == SHUT_WR || how == SHUT_RDWR)
1557 error = (*pr->pr_usrreq)(so, PRU_SHUTDOWN, NULL,
1558 NULL, NULL, NULL);
1559
1560 return error;
1561 }
1562
1563 int
1564 sodrain(struct socket *so)
1565 {
1566 int error;
1567
1568 solock(so);
1569 so->so_state |= SS_ISDRAINING;
1570 cv_broadcast(&so->so_cv);
1571 error = soshutdown(so, SHUT_RDWR);
1572 sounlock(so);
1573
1574 return error;
1575 }
1576
1577 void
1578 sorflush(struct socket *so)
1579 {
1580 struct sockbuf *sb, asb;
1581 const struct protosw *pr;
1582
1583 KASSERT(solocked(so));
1584
1585 sb = &so->so_rcv;
1586 pr = so->so_proto;
1587 socantrcvmore(so);
1588 sb->sb_flags |= SB_NOINTR;
1589 (void )sblock(sb, M_WAITOK);
1590 sbunlock(sb);
1591 asb = *sb;
1592 /*
1593 * Clear most of the sockbuf structure, but leave some of the
1594 * fields valid.
1595 */
1596 memset(&sb->sb_startzero, 0,
1597 sizeof(*sb) - offsetof(struct sockbuf, sb_startzero));
1598 if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) {
1599 sounlock(so);
1600 (*pr->pr_domain->dom_dispose)(asb.sb_mb);
1601 solock(so);
1602 }
1603 sbrelease(&asb, so);
1604 }
1605
1606 /*
1607 * internal set SOL_SOCKET options
1608 */
1609 static int
1610 sosetopt1(struct socket *so, const struct sockopt *sopt)
1611 {
1612 int error = EINVAL, optval, opt;
1613 struct linger l;
1614 struct timeval tv;
1615
1616 switch ((opt = sopt->sopt_name)) {
1617
1618 case SO_ACCEPTFILTER:
1619 error = accept_filt_setopt(so, sopt);
1620 KASSERT(solocked(so));
1621 break;
1622
1623 case SO_LINGER:
1624 error = sockopt_get(sopt, &l, sizeof(l));
1625 solock(so);
1626 if (error)
1627 break;
1628 if (l.l_linger < 0 || l.l_linger > USHRT_MAX ||
1629 l.l_linger > (INT_MAX / hz)) {
1630 error = EDOM;
1631 break;
1632 }
1633 so->so_linger = l.l_linger;
1634 if (l.l_onoff)
1635 so->so_options |= SO_LINGER;
1636 else
1637 so->so_options &= ~SO_LINGER;
1638 break;
1639
1640 case SO_DEBUG:
1641 case SO_KEEPALIVE:
1642 case SO_DONTROUTE:
1643 case SO_USELOOPBACK:
1644 case SO_BROADCAST:
1645 case SO_REUSEADDR:
1646 case SO_REUSEPORT:
1647 case SO_OOBINLINE:
1648 case SO_TIMESTAMP:
1649 #ifdef SO_OTIMESTAMP
1650 case SO_OTIMESTAMP:
1651 #endif
1652 error = sockopt_getint(sopt, &optval);
1653 solock(so);
1654 if (error)
1655 break;
1656 if (optval)
1657 so->so_options |= opt;
1658 else
1659 so->so_options &= ~opt;
1660 break;
1661
1662 case SO_SNDBUF:
1663 case SO_RCVBUF:
1664 case SO_SNDLOWAT:
1665 case SO_RCVLOWAT:
1666 error = sockopt_getint(sopt, &optval);
1667 solock(so);
1668 if (error)
1669 break;
1670
1671 /*
1672 * Values < 1 make no sense for any of these
1673 * options, so disallow them.
1674 */
1675 if (optval < 1) {
1676 error = EINVAL;
1677 break;
1678 }
1679
1680 switch (opt) {
1681 case SO_SNDBUF:
1682 if (sbreserve(&so->so_snd, (u_long)optval, so) == 0) {
1683 error = ENOBUFS;
1684 break;
1685 }
1686 so->so_snd.sb_flags &= ~SB_AUTOSIZE;
1687 break;
1688
1689 case SO_RCVBUF:
1690 if (sbreserve(&so->so_rcv, (u_long)optval, so) == 0) {
1691 error = ENOBUFS;
1692 break;
1693 }
1694 so->so_rcv.sb_flags &= ~SB_AUTOSIZE;
1695 break;
1696
1697 /*
1698 * Make sure the low-water is never greater than
1699 * the high-water.
1700 */
1701 case SO_SNDLOWAT:
1702 if (optval > so->so_snd.sb_hiwat)
1703 optval = so->so_snd.sb_hiwat;
1704
1705 so->so_snd.sb_lowat = optval;
1706 break;
1707
1708 case SO_RCVLOWAT:
1709 if (optval > so->so_rcv.sb_hiwat)
1710 optval = so->so_rcv.sb_hiwat;
1711
1712 so->so_rcv.sb_lowat = optval;
1713 break;
1714 }
1715 break;
1716
1717 #ifdef COMPAT_50
1718 case SO_OSNDTIMEO:
1719 case SO_ORCVTIMEO: {
1720 struct timeval50 otv;
1721 error = sockopt_get(sopt, &otv, sizeof(otv));
1722 if (error) {
1723 solock(so);
1724 break;
1725 }
1726 timeval50_to_timeval(&otv, &tv);
1727 opt = opt == SO_OSNDTIMEO ? SO_SNDTIMEO : SO_RCVTIMEO;
1728 error = 0;
1729 /*FALLTHROUGH*/
1730 }
1731 #endif /* COMPAT_50 */
1732
1733 case SO_SNDTIMEO:
1734 case SO_RCVTIMEO:
1735 if (error)
1736 error = sockopt_get(sopt, &tv, sizeof(tv));
1737 solock(so);
1738 if (error)
1739 break;
1740
1741 if (tv.tv_sec > (INT_MAX - tv.tv_usec / tick) / hz) {
1742 error = EDOM;
1743 break;
1744 }
1745
1746 optval = tv.tv_sec * hz + tv.tv_usec / tick;
1747 if (optval == 0 && tv.tv_usec != 0)
1748 optval = 1;
1749
1750 switch (opt) {
1751 case SO_SNDTIMEO:
1752 so->so_snd.sb_timeo = optval;
1753 break;
1754 case SO_RCVTIMEO:
1755 so->so_rcv.sb_timeo = optval;
1756 break;
1757 }
1758 break;
1759
1760 default:
1761 solock(so);
1762 error = ENOPROTOOPT;
1763 break;
1764 }
1765 KASSERT(solocked(so));
1766 return error;
1767 }
1768
1769 int
1770 sosetopt(struct socket *so, struct sockopt *sopt)
1771 {
1772 int error, prerr;
1773
1774 if (sopt->sopt_level == SOL_SOCKET) {
1775 error = sosetopt1(so, sopt);
1776 KASSERT(solocked(so));
1777 } else {
1778 error = ENOPROTOOPT;
1779 solock(so);
1780 }
1781
1782 if ((error == 0 || error == ENOPROTOOPT) &&
1783 so->so_proto != NULL && so->so_proto->pr_ctloutput != NULL) {
1784 /* give the protocol stack a shot */
1785 prerr = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, sopt);
1786 if (prerr == 0)
1787 error = 0;
1788 else if (prerr != ENOPROTOOPT)
1789 error = prerr;
1790 }
1791 sounlock(so);
1792 return error;
1793 }
1794
1795 /*
1796 * so_setsockopt() is a wrapper providing a sockopt structure for sosetopt()
1797 */
1798 int
1799 so_setsockopt(struct lwp *l, struct socket *so, int level, int name,
1800 const void *val, size_t valsize)
1801 {
1802 struct sockopt sopt;
1803 int error;
1804
1805 KASSERT(valsize == 0 || val != NULL);
1806
1807 sockopt_init(&sopt, level, name, valsize);
1808 sockopt_set(&sopt, val, valsize);
1809
1810 error = sosetopt(so, &sopt);
1811
1812 sockopt_destroy(&sopt);
1813
1814 return error;
1815 }
1816
1817 /*
1818 * internal get SOL_SOCKET options
1819 */
1820 static int
1821 sogetopt1(struct socket *so, struct sockopt *sopt)
1822 {
1823 int error, optval, opt;
1824 struct linger l;
1825 struct timeval tv;
1826
1827 switch ((opt = sopt->sopt_name)) {
1828
1829 case SO_ACCEPTFILTER:
1830 error = accept_filt_getopt(so, sopt);
1831 break;
1832
1833 case SO_LINGER:
1834 l.l_onoff = (so->so_options & SO_LINGER) ? 1 : 0;
1835 l.l_linger = so->so_linger;
1836
1837 error = sockopt_set(sopt, &l, sizeof(l));
1838 break;
1839
1840 case SO_USELOOPBACK:
1841 case SO_DONTROUTE:
1842 case SO_DEBUG:
1843 case SO_KEEPALIVE:
1844 case SO_REUSEADDR:
1845 case SO_REUSEPORT:
1846 case SO_BROADCAST:
1847 case SO_OOBINLINE:
1848 case SO_TIMESTAMP:
1849 #ifdef SO_OTIMESTAMP
1850 case SO_OTIMESTAMP:
1851 #endif
1852 error = sockopt_setint(sopt, (so->so_options & opt) ? 1 : 0);
1853 break;
1854
1855 case SO_TYPE:
1856 error = sockopt_setint(sopt, so->so_type);
1857 break;
1858
1859 case SO_ERROR:
1860 error = sockopt_setint(sopt, so->so_error);
1861 so->so_error = 0;
1862 break;
1863
1864 case SO_SNDBUF:
1865 error = sockopt_setint(sopt, so->so_snd.sb_hiwat);
1866 break;
1867
1868 case SO_RCVBUF:
1869 error = sockopt_setint(sopt, so->so_rcv.sb_hiwat);
1870 break;
1871
1872 case SO_SNDLOWAT:
1873 error = sockopt_setint(sopt, so->so_snd.sb_lowat);
1874 break;
1875
1876 case SO_RCVLOWAT:
1877 error = sockopt_setint(sopt, so->so_rcv.sb_lowat);
1878 break;
1879
1880 #ifdef COMPAT_50
1881 case SO_OSNDTIMEO:
1882 case SO_ORCVTIMEO: {
1883 struct timeval50 otv;
1884
1885 optval = (opt == SO_OSNDTIMEO ?
1886 so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
1887
1888 otv.tv_sec = optval / hz;
1889 otv.tv_usec = (optval % hz) * tick;
1890
1891 error = sockopt_set(sopt, &otv, sizeof(otv));
1892 break;
1893 }
1894 #endif /* COMPAT_50 */
1895
1896 case SO_SNDTIMEO:
1897 case SO_RCVTIMEO:
1898 optval = (opt == SO_SNDTIMEO ?
1899 so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
1900
1901 tv.tv_sec = optval / hz;
1902 tv.tv_usec = (optval % hz) * tick;
1903
1904 error = sockopt_set(sopt, &tv, sizeof(tv));
1905 break;
1906
1907 case SO_OVERFLOWED:
1908 error = sockopt_setint(sopt, so->so_rcv.sb_overflowed);
1909 break;
1910
1911 default:
1912 error = ENOPROTOOPT;
1913 break;
1914 }
1915
1916 return (error);
1917 }
1918
1919 int
1920 sogetopt(struct socket *so, struct sockopt *sopt)
1921 {
1922 int error;
1923
1924 solock(so);
1925 if (sopt->sopt_level != SOL_SOCKET) {
1926 if (so->so_proto && so->so_proto->pr_ctloutput) {
1927 error = ((*so->so_proto->pr_ctloutput)
1928 (PRCO_GETOPT, so, sopt));
1929 } else
1930 error = (ENOPROTOOPT);
1931 } else {
1932 error = sogetopt1(so, sopt);
1933 }
1934 sounlock(so);
1935 return (error);
1936 }
1937
1938 /*
1939 * alloc sockopt data buffer buffer
1940 * - will be released at destroy
1941 */
1942 static int
1943 sockopt_alloc(struct sockopt *sopt, size_t len, km_flag_t kmflag)
1944 {
1945
1946 KASSERT(sopt->sopt_size == 0);
1947
1948 if (len > sizeof(sopt->sopt_buf)) {
1949 sopt->sopt_data = kmem_zalloc(len, kmflag);
1950 if (sopt->sopt_data == NULL)
1951 return ENOMEM;
1952 } else
1953 sopt->sopt_data = sopt->sopt_buf;
1954
1955 sopt->sopt_size = len;
1956 return 0;
1957 }
1958
1959 /*
1960 * initialise sockopt storage
1961 * - MAY sleep during allocation
1962 */
1963 void
1964 sockopt_init(struct sockopt *sopt, int level, int name, size_t size)
1965 {
1966
1967 memset(sopt, 0, sizeof(*sopt));
1968
1969 sopt->sopt_level = level;
1970 sopt->sopt_name = name;
1971 (void)sockopt_alloc(sopt, size, KM_SLEEP);
1972 }
1973
1974 /*
1975 * destroy sockopt storage
1976 * - will release any held memory references
1977 */
1978 void
1979 sockopt_destroy(struct sockopt *sopt)
1980 {
1981
1982 if (sopt->sopt_data != sopt->sopt_buf)
1983 kmem_free(sopt->sopt_data, sopt->sopt_size);
1984
1985 memset(sopt, 0, sizeof(*sopt));
1986 }
1987
1988 /*
1989 * set sockopt value
1990 * - value is copied into sockopt
1991 * - memory is allocated when necessary, will not sleep
1992 */
1993 int
1994 sockopt_set(struct sockopt *sopt, const void *buf, size_t len)
1995 {
1996 int error;
1997
1998 if (sopt->sopt_size == 0) {
1999 error = sockopt_alloc(sopt, len, KM_NOSLEEP);
2000 if (error)
2001 return error;
2002 }
2003
2004 KASSERT(sopt->sopt_size == len);
2005 memcpy(sopt->sopt_data, buf, len);
2006 return 0;
2007 }
2008
2009 /*
2010 * common case of set sockopt integer value
2011 */
2012 int
2013 sockopt_setint(struct sockopt *sopt, int val)
2014 {
2015
2016 return sockopt_set(sopt, &val, sizeof(int));
2017 }
2018
2019 /*
2020 * get sockopt value
2021 * - correct size must be given
2022 */
2023 int
2024 sockopt_get(const struct sockopt *sopt, void *buf, size_t len)
2025 {
2026
2027 if (sopt->sopt_size != len)
2028 return EINVAL;
2029
2030 memcpy(buf, sopt->sopt_data, len);
2031 return 0;
2032 }
2033
2034 /*
2035 * common case of get sockopt integer value
2036 */
2037 int
2038 sockopt_getint(const struct sockopt *sopt, int *valp)
2039 {
2040
2041 return sockopt_get(sopt, valp, sizeof(int));
2042 }
2043
2044 /*
2045 * set sockopt value from mbuf
2046 * - ONLY for legacy code
2047 * - mbuf is released by sockopt
2048 * - will not sleep
2049 */
2050 int
2051 sockopt_setmbuf(struct sockopt *sopt, struct mbuf *m)
2052 {
2053 size_t len;
2054 int error;
2055
2056 len = m_length(m);
2057
2058 if (sopt->sopt_size == 0) {
2059 error = sockopt_alloc(sopt, len, KM_NOSLEEP);
2060 if (error)
2061 return error;
2062 }
2063
2064 KASSERT(sopt->sopt_size == len);
2065 m_copydata(m, 0, len, sopt->sopt_data);
2066 m_freem(m);
2067
2068 return 0;
2069 }
2070
2071 /*
2072 * get sockopt value into mbuf
2073 * - ONLY for legacy code
2074 * - mbuf to be released by the caller
2075 * - will not sleep
2076 */
2077 struct mbuf *
2078 sockopt_getmbuf(const struct sockopt *sopt)
2079 {
2080 struct mbuf *m;
2081
2082 if (sopt->sopt_size > MCLBYTES)
2083 return NULL;
2084
2085 m = m_get(M_DONTWAIT, MT_SOOPTS);
2086 if (m == NULL)
2087 return NULL;
2088
2089 if (sopt->sopt_size > MLEN) {
2090 MCLGET(m, M_DONTWAIT);
2091 if ((m->m_flags & M_EXT) == 0) {
2092 m_free(m);
2093 return NULL;
2094 }
2095 }
2096
2097 memcpy(mtod(m, void *), sopt->sopt_data, sopt->sopt_size);
2098 m->m_len = sopt->sopt_size;
2099
2100 return m;
2101 }
2102
2103 void
2104 sohasoutofband(struct socket *so)
2105 {
2106
2107 fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so);
2108 selnotify(&so->so_rcv.sb_sel, POLLPRI | POLLRDBAND, NOTE_SUBMIT);
2109 }
2110
2111 static void
2112 filt_sordetach(struct knote *kn)
2113 {
2114 struct socket *so;
2115
2116 so = ((file_t *)kn->kn_obj)->f_data;
2117 solock(so);
2118 SLIST_REMOVE(&so->so_rcv.sb_sel.sel_klist, kn, knote, kn_selnext);
2119 if (SLIST_EMPTY(&so->so_rcv.sb_sel.sel_klist))
2120 so->so_rcv.sb_flags &= ~SB_KNOTE;
2121 sounlock(so);
2122 }
2123
2124 /*ARGSUSED*/
2125 static int
2126 filt_soread(struct knote *kn, long hint)
2127 {
2128 struct socket *so;
2129 int rv;
2130
2131 so = ((file_t *)kn->kn_obj)->f_data;
2132 if (hint != NOTE_SUBMIT)
2133 solock(so);
2134 kn->kn_data = so->so_rcv.sb_cc;
2135 if (so->so_state & SS_CANTRCVMORE) {
2136 kn->kn_flags |= EV_EOF;
2137 kn->kn_fflags = so->so_error;
2138 rv = 1;
2139 } else if (so->so_error) /* temporary udp error */
2140 rv = 1;
2141 else if (kn->kn_sfflags & NOTE_LOWAT)
2142 rv = (kn->kn_data >= kn->kn_sdata);
2143 else
2144 rv = (kn->kn_data >= so->so_rcv.sb_lowat);
2145 if (hint != NOTE_SUBMIT)
2146 sounlock(so);
2147 return rv;
2148 }
2149
2150 static void
2151 filt_sowdetach(struct knote *kn)
2152 {
2153 struct socket *so;
2154
2155 so = ((file_t *)kn->kn_obj)->f_data;
2156 solock(so);
2157 SLIST_REMOVE(&so->so_snd.sb_sel.sel_klist, kn, knote, kn_selnext);
2158 if (SLIST_EMPTY(&so->so_snd.sb_sel.sel_klist))
2159 so->so_snd.sb_flags &= ~SB_KNOTE;
2160 sounlock(so);
2161 }
2162
2163 /*ARGSUSED*/
2164 static int
2165 filt_sowrite(struct knote *kn, long hint)
2166 {
2167 struct socket *so;
2168 int rv;
2169
2170 so = ((file_t *)kn->kn_obj)->f_data;
2171 if (hint != NOTE_SUBMIT)
2172 solock(so);
2173 kn->kn_data = sbspace(&so->so_snd);
2174 if (so->so_state & SS_CANTSENDMORE) {
2175 kn->kn_flags |= EV_EOF;
2176 kn->kn_fflags = so->so_error;
2177 rv = 1;
2178 } else if (so->so_error) /* temporary udp error */
2179 rv = 1;
2180 else if (((so->so_state & SS_ISCONNECTED) == 0) &&
2181 (so->so_proto->pr_flags & PR_CONNREQUIRED))
2182 rv = 0;
2183 else if (kn->kn_sfflags & NOTE_LOWAT)
2184 rv = (kn->kn_data >= kn->kn_sdata);
2185 else
2186 rv = (kn->kn_data >= so->so_snd.sb_lowat);
2187 if (hint != NOTE_SUBMIT)
2188 sounlock(so);
2189 return rv;
2190 }
2191
2192 /*ARGSUSED*/
2193 static int
2194 filt_solisten(struct knote *kn, long hint)
2195 {
2196 struct socket *so;
2197 int rv;
2198
2199 so = ((file_t *)kn->kn_obj)->f_data;
2200
2201 /*
2202 * Set kn_data to number of incoming connections, not
2203 * counting partial (incomplete) connections.
2204 */
2205 if (hint != NOTE_SUBMIT)
2206 solock(so);
2207 kn->kn_data = so->so_qlen;
2208 rv = (kn->kn_data > 0);
2209 if (hint != NOTE_SUBMIT)
2210 sounlock(so);
2211 return rv;
2212 }
2213
2214 static const struct filterops solisten_filtops =
2215 { 1, NULL, filt_sordetach, filt_solisten };
2216 static const struct filterops soread_filtops =
2217 { 1, NULL, filt_sordetach, filt_soread };
2218 static const struct filterops sowrite_filtops =
2219 { 1, NULL, filt_sowdetach, filt_sowrite };
2220
2221 int
2222 soo_kqfilter(struct file *fp, struct knote *kn)
2223 {
2224 struct socket *so;
2225 struct sockbuf *sb;
2226
2227 so = ((file_t *)kn->kn_obj)->f_data;
2228 solock(so);
2229 switch (kn->kn_filter) {
2230 case EVFILT_READ:
2231 if (so->so_options & SO_ACCEPTCONN)
2232 kn->kn_fop = &solisten_filtops;
2233 else
2234 kn->kn_fop = &soread_filtops;
2235 sb = &so->so_rcv;
2236 break;
2237 case EVFILT_WRITE:
2238 kn->kn_fop = &sowrite_filtops;
2239 sb = &so->so_snd;
2240 break;
2241 default:
2242 sounlock(so);
2243 return (EINVAL);
2244 }
2245 SLIST_INSERT_HEAD(&sb->sb_sel.sel_klist, kn, kn_selnext);
2246 sb->sb_flags |= SB_KNOTE;
2247 sounlock(so);
2248 return (0);
2249 }
2250
2251 static int
2252 sodopoll(struct socket *so, int events)
2253 {
2254 int revents;
2255
2256 revents = 0;
2257
2258 if (events & (POLLIN | POLLRDNORM))
2259 if (soreadable(so))
2260 revents |= events & (POLLIN | POLLRDNORM);
2261
2262 if (events & (POLLOUT | POLLWRNORM))
2263 if (sowritable(so))
2264 revents |= events & (POLLOUT | POLLWRNORM);
2265
2266 if (events & (POLLPRI | POLLRDBAND))
2267 if (so->so_oobmark || (so->so_state & SS_RCVATMARK))
2268 revents |= events & (POLLPRI | POLLRDBAND);
2269
2270 return revents;
2271 }
2272
2273 int
2274 sopoll(struct socket *so, int events)
2275 {
2276 int revents = 0;
2277
2278 #ifndef DIAGNOSTIC
2279 /*
2280 * Do a quick, unlocked check in expectation that the socket
2281 * will be ready for I/O. Don't do this check if DIAGNOSTIC,
2282 * as the solocked() assertions will fail.
2283 */
2284 if ((revents = sodopoll(so, events)) != 0)
2285 return revents;
2286 #endif
2287
2288 solock(so);
2289 if ((revents = sodopoll(so, events)) == 0) {
2290 if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
2291 selrecord(curlwp, &so->so_rcv.sb_sel);
2292 so->so_rcv.sb_flags |= SB_NOTIFY;
2293 }
2294
2295 if (events & (POLLOUT | POLLWRNORM)) {
2296 selrecord(curlwp, &so->so_snd.sb_sel);
2297 so->so_snd.sb_flags |= SB_NOTIFY;
2298 }
2299 }
2300 sounlock(so);
2301
2302 return revents;
2303 }
2304
2305
2306 #include <sys/sysctl.h>
2307
2308 static int sysctl_kern_somaxkva(SYSCTLFN_PROTO);
2309
2310 /*
2311 * sysctl helper routine for kern.somaxkva. ensures that the given
2312 * value is not too small.
2313 * (XXX should we maybe make sure it's not too large as well?)
2314 */
2315 static int
2316 sysctl_kern_somaxkva(SYSCTLFN_ARGS)
2317 {
2318 int error, new_somaxkva;
2319 struct sysctlnode node;
2320
2321 new_somaxkva = somaxkva;
2322 node = *rnode;
2323 node.sysctl_data = &new_somaxkva;
2324 error = sysctl_lookup(SYSCTLFN_CALL(&node));
2325 if (error || newp == NULL)
2326 return (error);
2327
2328 if (new_somaxkva < (16 * 1024 * 1024)) /* sanity */
2329 return (EINVAL);
2330
2331 mutex_enter(&so_pendfree_lock);
2332 somaxkva = new_somaxkva;
2333 cv_broadcast(&socurkva_cv);
2334 mutex_exit(&so_pendfree_lock);
2335
2336 return (error);
2337 }
2338
2339 static void
2340 sysctl_kern_somaxkva_setup(void)
2341 {
2342
2343 KASSERT(socket_sysctllog == NULL);
2344 sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
2345 CTLFLAG_PERMANENT,
2346 CTLTYPE_NODE, "kern", NULL,
2347 NULL, 0, NULL, 0,
2348 CTL_KERN, CTL_EOL);
2349
2350 sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
2351 CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2352 CTLTYPE_INT, "somaxkva",
2353 SYSCTL_DESCR("Maximum amount of kernel memory to be "
2354 "used for socket buffers"),
2355 sysctl_kern_somaxkva, 0, NULL, 0,
2356 CTL_KERN, KERN_SOMAXKVA, CTL_EOL);
2357 }
2358