xref: /netbsd-src/sys/kern/uipc_socket.c (revision 9aa0541bdf64142d9a27c2cf274394d60182818f)
1 /*	$NetBSD: uipc_socket.c,v 1.205 2011/07/02 17:53:50 bouyer 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 1.205 2011/07/02 17:53:50 bouyer 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 #include <sys/kthread.h>
96 
97 #ifdef COMPAT_50
98 #include <compat/sys/time.h>
99 #include <compat/sys/socket.h>
100 #endif
101 
102 #include <uvm/uvm_extern.h>
103 #include <uvm/uvm_loan.h>
104 #include <uvm/uvm_page.h>
105 
106 MALLOC_DEFINE(M_SOOPTS, "soopts", "socket options");
107 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
108 
109 extern const struct fileops socketops;
110 
111 extern int	somaxconn;			/* patchable (XXX sysctl) */
112 int		somaxconn = SOMAXCONN;
113 kmutex_t	*softnet_lock;
114 
115 #ifdef SOSEND_COUNTERS
116 #include <sys/device.h>
117 
118 static struct evcnt sosend_loan_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
119     NULL, "sosend", "loan big");
120 static struct evcnt sosend_copy_big = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
121     NULL, "sosend", "copy big");
122 static struct evcnt sosend_copy_small = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
123     NULL, "sosend", "copy small");
124 static struct evcnt sosend_kvalimit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
125     NULL, "sosend", "kva limit");
126 
127 #define	SOSEND_COUNTER_INCR(ev)		(ev)->ev_count++
128 
129 EVCNT_ATTACH_STATIC(sosend_loan_big);
130 EVCNT_ATTACH_STATIC(sosend_copy_big);
131 EVCNT_ATTACH_STATIC(sosend_copy_small);
132 EVCNT_ATTACH_STATIC(sosend_kvalimit);
133 #else
134 
135 #define	SOSEND_COUNTER_INCR(ev)		/* nothing */
136 
137 #endif /* SOSEND_COUNTERS */
138 
139 static struct callback_entry sokva_reclaimerentry;
140 
141 #if defined(SOSEND_NO_LOAN) || defined(MULTIPROCESSOR)
142 int sock_loan_thresh = -1;
143 #else
144 int sock_loan_thresh = 4096;
145 #endif
146 
147 static kmutex_t so_pendfree_lock;
148 static struct mbuf *so_pendfree = NULL;
149 
150 #ifndef SOMAXKVA
151 #define	SOMAXKVA (16 * 1024 * 1024)
152 #endif
153 int somaxkva = SOMAXKVA;
154 static int socurkva;
155 static kcondvar_t socurkva_cv;
156 
157 static kauth_listener_t socket_listener;
158 
159 #define	SOCK_LOAN_CHUNK		65536
160 
161 static void sopendfree_thread(void *);
162 static kcondvar_t pendfree_thread_cv;
163 static lwp_t *sopendfree_lwp;
164 
165 static void sysctl_kern_somaxkva_setup(void);
166 static struct sysctllog *socket_sysctllog;
167 
168 static vsize_t
169 sokvareserve(struct socket *so, vsize_t len)
170 {
171 	int error;
172 
173 	mutex_enter(&so_pendfree_lock);
174 	while (socurkva + len > somaxkva) {
175 		SOSEND_COUNTER_INCR(&sosend_kvalimit);
176 		error = cv_wait_sig(&socurkva_cv, &so_pendfree_lock);
177 		if (error) {
178 			len = 0;
179 			break;
180 		}
181 	}
182 	socurkva += len;
183 	mutex_exit(&so_pendfree_lock);
184 	return len;
185 }
186 
187 static void
188 sokvaunreserve(vsize_t len)
189 {
190 
191 	mutex_enter(&so_pendfree_lock);
192 	socurkva -= len;
193 	cv_broadcast(&socurkva_cv);
194 	mutex_exit(&so_pendfree_lock);
195 }
196 
197 /*
198  * sokvaalloc: allocate kva for loan.
199  */
200 
201 vaddr_t
202 sokvaalloc(vsize_t len, struct socket *so)
203 {
204 	vaddr_t lva;
205 
206 	/*
207 	 * reserve kva.
208 	 */
209 
210 	if (sokvareserve(so, len) == 0)
211 		return 0;
212 
213 	/*
214 	 * allocate kva.
215 	 */
216 
217 	lva = uvm_km_alloc(kernel_map, len, 0, UVM_KMF_VAONLY | UVM_KMF_WAITVA);
218 	if (lva == 0) {
219 		sokvaunreserve(len);
220 		return (0);
221 	}
222 
223 	return lva;
224 }
225 
226 /*
227  * sokvafree: free kva for loan.
228  */
229 
230 void
231 sokvafree(vaddr_t sva, vsize_t len)
232 {
233 
234 	/*
235 	 * free kva.
236 	 */
237 
238 	uvm_km_free(kernel_map, sva, len, UVM_KMF_VAONLY);
239 
240 	/*
241 	 * unreserve kva.
242 	 */
243 
244 	sokvaunreserve(len);
245 }
246 
247 static void
248 sodoloanfree(struct vm_page **pgs, void *buf, size_t size)
249 {
250 	vaddr_t sva, eva;
251 	vsize_t len;
252 	int npgs;
253 
254 	KASSERT(pgs != NULL);
255 
256 	eva = round_page((vaddr_t) buf + size);
257 	sva = trunc_page((vaddr_t) buf);
258 	len = eva - sva;
259 	npgs = len >> PAGE_SHIFT;
260 
261 	pmap_kremove(sva, len);
262 	pmap_update(pmap_kernel());
263 	uvm_unloan(pgs, npgs, UVM_LOAN_TOPAGE);
264 	sokvafree(sva, len);
265 }
266 
267 /*
268  * sopendfree_thread: free mbufs on "pendfree" list.
269  * unlock and relock so_pendfree_lock when freeing mbufs.
270  */
271 
272 static void
273 sopendfree_thread(void *v)
274 {
275 	struct mbuf *m, *next;
276 	size_t rv;
277 
278 	mutex_enter(&so_pendfree_lock);
279 
280 	for (;;) {
281 		rv = 0;
282 		while (so_pendfree != NULL) {
283 			m = so_pendfree;
284 			so_pendfree = NULL;
285 			mutex_exit(&so_pendfree_lock);
286 
287 			for (; m != NULL; m = next) {
288 				next = m->m_next;
289 				KASSERT((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0);
290 				KASSERT(m->m_ext.ext_refcnt == 0);
291 
292 				rv += m->m_ext.ext_size;
293 				sodoloanfree(m->m_ext.ext_pgs, m->m_ext.ext_buf,
294 				    m->m_ext.ext_size);
295 				pool_cache_put(mb_cache, m);
296 			}
297 
298 			mutex_enter(&so_pendfree_lock);
299 		}
300 		if (rv)
301 			cv_broadcast(&socurkva_cv);
302 		cv_wait(&pendfree_thread_cv, &so_pendfree_lock);
303 	}
304 	panic("sopendfree_thread");
305 	/* NOTREACHED */
306 }
307 
308 void
309 soloanfree(struct mbuf *m, void *buf, size_t size, void *arg)
310 {
311 
312 	KASSERT(m != NULL);
313 
314 	/*
315 	 * postpone freeing mbuf.
316 	 *
317 	 * we can't do it in interrupt context
318 	 * because we need to put kva back to kernel_map.
319 	 */
320 
321 	mutex_enter(&so_pendfree_lock);
322 	m->m_next = so_pendfree;
323 	so_pendfree = m;
324 	cv_signal(&pendfree_thread_cv);
325 	mutex_exit(&so_pendfree_lock);
326 }
327 
328 static long
329 sosend_loan(struct socket *so, struct uio *uio, struct mbuf *m, long space)
330 {
331 	struct iovec *iov = uio->uio_iov;
332 	vaddr_t sva, eva;
333 	vsize_t len;
334 	vaddr_t lva;
335 	int npgs, error;
336 	vaddr_t va;
337 	int i;
338 
339 	if (VMSPACE_IS_KERNEL_P(uio->uio_vmspace))
340 		return (0);
341 
342 	if (iov->iov_len < (size_t) space)
343 		space = iov->iov_len;
344 	if (space > SOCK_LOAN_CHUNK)
345 		space = SOCK_LOAN_CHUNK;
346 
347 	eva = round_page((vaddr_t) iov->iov_base + space);
348 	sva = trunc_page((vaddr_t) iov->iov_base);
349 	len = eva - sva;
350 	npgs = len >> PAGE_SHIFT;
351 
352 	KASSERT(npgs <= M_EXT_MAXPAGES);
353 
354 	lva = sokvaalloc(len, so);
355 	if (lva == 0)
356 		return 0;
357 
358 	error = uvm_loan(&uio->uio_vmspace->vm_map, sva, len,
359 	    m->m_ext.ext_pgs, UVM_LOAN_TOPAGE);
360 	if (error) {
361 		sokvafree(lva, len);
362 		return (0);
363 	}
364 
365 	for (i = 0, va = lva; i < npgs; i++, va += PAGE_SIZE)
366 		pmap_kenter_pa(va, VM_PAGE_TO_PHYS(m->m_ext.ext_pgs[i]),
367 		    VM_PROT_READ, 0);
368 	pmap_update(pmap_kernel());
369 
370 	lva += (vaddr_t) iov->iov_base & PAGE_MASK;
371 
372 	MEXTADD(m, (void *) lva, space, M_MBUF, soloanfree, so);
373 	m->m_flags |= M_EXT_PAGES | M_EXT_ROMAP;
374 
375 	uio->uio_resid -= space;
376 	/* uio_offset not updated, not set/used for write(2) */
377 	uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + space;
378 	uio->uio_iov->iov_len -= space;
379 	if (uio->uio_iov->iov_len == 0) {
380 		uio->uio_iov++;
381 		uio->uio_iovcnt--;
382 	}
383 
384 	return (space);
385 }
386 
387 static int
388 sokva_reclaim_callback(struct callback_entry *ce, void *obj, void *arg)
389 {
390 
391 	KASSERT(ce == &sokva_reclaimerentry);
392 	KASSERT(obj == NULL);
393 
394 	if (!vm_map_starved_p(kernel_map)) {
395 		return CALLBACK_CHAIN_ABORT;
396 	}
397 	return CALLBACK_CHAIN_CONTINUE;
398 }
399 
400 struct mbuf *
401 getsombuf(struct socket *so, int type)
402 {
403 	struct mbuf *m;
404 
405 	m = m_get(M_WAIT, type);
406 	MCLAIM(m, so->so_mowner);
407 	return m;
408 }
409 
410 static int
411 socket_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
412     void *arg0, void *arg1, void *arg2, void *arg3)
413 {
414 	int result;
415 	enum kauth_network_req req;
416 
417 	result = KAUTH_RESULT_DEFER;
418 	req = (enum kauth_network_req)arg0;
419 
420 	if ((action != KAUTH_NETWORK_SOCKET) &&
421 	    (action != KAUTH_NETWORK_BIND))
422 		return result;
423 
424 	switch (req) {
425 	case KAUTH_REQ_NETWORK_BIND_PORT:
426 		result = KAUTH_RESULT_ALLOW;
427 		break;
428 
429 	case KAUTH_REQ_NETWORK_SOCKET_DROP: {
430 		/* Normal users can only drop their own connections. */
431 		struct socket *so = (struct socket *)arg1;
432 
433 		if (proc_uidmatch(cred, so->so_cred))
434 			result = KAUTH_RESULT_ALLOW;
435 
436 		break;
437 		}
438 
439 	case KAUTH_REQ_NETWORK_SOCKET_OPEN:
440 		/* We allow "raw" routing/bluetooth sockets to anyone. */
441 		if ((u_long)arg1 == PF_ROUTE || (u_long)arg1 == PF_OROUTE
442 		    || (u_long)arg1 == PF_BLUETOOTH) {
443 			result = KAUTH_RESULT_ALLOW;
444 		} else {
445 			/* Privileged, let secmodel handle this. */
446 			if ((u_long)arg2 == SOCK_RAW)
447 				break;
448 		}
449 
450 		result = KAUTH_RESULT_ALLOW;
451 
452 		break;
453 
454 	case KAUTH_REQ_NETWORK_SOCKET_CANSEE:
455 		result = KAUTH_RESULT_ALLOW;
456 
457 		break;
458 
459 	default:
460 		break;
461 	}
462 
463 	return result;
464 }
465 
466 void
467 soinit(void)
468 {
469 
470 	sysctl_kern_somaxkva_setup();
471 
472 	mutex_init(&so_pendfree_lock, MUTEX_DEFAULT, IPL_VM);
473 	softnet_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NONE);
474 	cv_init(&socurkva_cv, "sokva");
475 	cv_init(&pendfree_thread_cv, "sopendfr");
476 	soinit2();
477 
478 	/* Set the initial adjusted socket buffer size. */
479 	if (sb_max_set(sb_max))
480 		panic("bad initial sb_max value: %lu", sb_max);
481 
482 	callback_register(&vm_map_to_kernel(kernel_map)->vmk_reclaim_callback,
483 	    &sokva_reclaimerentry, NULL, sokva_reclaim_callback);
484 
485 	socket_listener = kauth_listen_scope(KAUTH_SCOPE_NETWORK,
486 	    socket_listener_cb, NULL);
487 }
488 
489 void
490 soinit1(void)
491 {
492 	int error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
493 	    sopendfree_thread, NULL, &sopendfree_lwp, "sopendfree");
494 	if (error)
495 		panic("soinit1 %d", error);
496 }
497 
498 /*
499  * Socket operation routines.
500  * These routines are called by the routines in
501  * sys_socket.c or from a system process, and
502  * implement the semantics of socket operations by
503  * switching out to the protocol specific routines.
504  */
505 /*ARGSUSED*/
506 int
507 socreate(int dom, struct socket **aso, int type, int proto, struct lwp *l,
508 	 struct socket *lockso)
509 {
510 	const struct protosw	*prp;
511 	struct socket	*so;
512 	uid_t		uid;
513 	int		error;
514 	kmutex_t	*lock;
515 
516 	error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_SOCKET,
517 	    KAUTH_REQ_NETWORK_SOCKET_OPEN, KAUTH_ARG(dom), KAUTH_ARG(type),
518 	    KAUTH_ARG(proto));
519 	if (error != 0)
520 		return error;
521 
522 	if (proto)
523 		prp = pffindproto(dom, proto, type);
524 	else
525 		prp = pffindtype(dom, type);
526 	if (prp == NULL) {
527 		/* no support for domain */
528 		if (pffinddomain(dom) == 0)
529 			return EAFNOSUPPORT;
530 		/* no support for socket type */
531 		if (proto == 0 && type != 0)
532 			return EPROTOTYPE;
533 		return EPROTONOSUPPORT;
534 	}
535 	if (prp->pr_usrreq == NULL)
536 		return EPROTONOSUPPORT;
537 	if (prp->pr_type != type)
538 		return EPROTOTYPE;
539 
540 	so = soget(true);
541 	so->so_type = type;
542 	so->so_proto = prp;
543 	so->so_send = sosend;
544 	so->so_receive = soreceive;
545 #ifdef MBUFTRACE
546 	so->so_rcv.sb_mowner = &prp->pr_domain->dom_mowner;
547 	so->so_snd.sb_mowner = &prp->pr_domain->dom_mowner;
548 	so->so_mowner = &prp->pr_domain->dom_mowner;
549 #endif
550 	uid = kauth_cred_geteuid(l->l_cred);
551 	so->so_uidinfo = uid_find(uid);
552 	so->so_cpid = l->l_proc->p_pid;
553 	if (lockso != NULL) {
554 		/* Caller wants us to share a lock. */
555 		lock = lockso->so_lock;
556 		so->so_lock = lock;
557 		mutex_obj_hold(lock);
558 		mutex_enter(lock);
559 	} else {
560 		/* Lock assigned and taken during PRU_ATTACH. */
561 	}
562 	error = (*prp->pr_usrreq)(so, PRU_ATTACH, NULL,
563 	    (struct mbuf *)(long)proto, NULL, l);
564 	KASSERT(solocked(so));
565 	if (error != 0) {
566 		so->so_state |= SS_NOFDREF;
567 		sofree(so);
568 		return error;
569 	}
570 	so->so_cred = kauth_cred_dup(l->l_cred);
571 	sounlock(so);
572 	*aso = so;
573 	return 0;
574 }
575 
576 /* On success, write file descriptor to fdout and return zero.  On
577  * failure, return non-zero; *fdout will be undefined.
578  */
579 int
580 fsocreate(int domain, struct socket **sop, int type, int protocol,
581     struct lwp *l, int *fdout)
582 {
583 	struct socket	*so;
584 	struct file	*fp;
585 	int		fd, error;
586 	int		flags = type & SOCK_FLAGS_MASK;
587 
588 	type &= ~SOCK_FLAGS_MASK;
589 	if ((error = fd_allocfile(&fp, &fd)) != 0)
590 		return error;
591 	fd_set_exclose(l, fd, (flags & SOCK_CLOEXEC) != 0);
592 	fp->f_flag = FREAD|FWRITE|((flags & SOCK_NONBLOCK) ? FNONBLOCK : 0);
593 	fp->f_type = DTYPE_SOCKET;
594 	fp->f_ops = &socketops;
595 	error = socreate(domain, &so, type, protocol, l, NULL);
596 	if (error != 0) {
597 		fd_abort(curproc, fp, fd);
598 	} else {
599 		if (sop != NULL)
600 			*sop = so;
601 		fp->f_data = so;
602 		fd_affix(curproc, fp, fd);
603 		*fdout = fd;
604 	}
605 	return error;
606 }
607 
608 int
609 sofamily(const struct socket *so)
610 {
611 	const struct protosw *pr;
612 	const struct domain *dom;
613 
614 	if ((pr = so->so_proto) == NULL)
615 		return AF_UNSPEC;
616 	if ((dom = pr->pr_domain) == NULL)
617 		return AF_UNSPEC;
618 	return dom->dom_family;
619 }
620 
621 int
622 sobind(struct socket *so, struct mbuf *nam, struct lwp *l)
623 {
624 	int	error;
625 
626 	solock(so);
627 	error = (*so->so_proto->pr_usrreq)(so, PRU_BIND, NULL, nam, NULL, l);
628 	sounlock(so);
629 	return error;
630 }
631 
632 int
633 solisten(struct socket *so, int backlog, struct lwp *l)
634 {
635 	int	error;
636 
637 	solock(so);
638 	if ((so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING |
639 	    SS_ISDISCONNECTING)) != 0) {
640 	    	sounlock(so);
641 		return (EOPNOTSUPP);
642 	}
643 	error = (*so->so_proto->pr_usrreq)(so, PRU_LISTEN, NULL,
644 	    NULL, NULL, l);
645 	if (error != 0) {
646 		sounlock(so);
647 		return error;
648 	}
649 	if (TAILQ_EMPTY(&so->so_q))
650 		so->so_options |= SO_ACCEPTCONN;
651 	if (backlog < 0)
652 		backlog = 0;
653 	so->so_qlimit = min(backlog, somaxconn);
654 	sounlock(so);
655 	return 0;
656 }
657 
658 void
659 sofree(struct socket *so)
660 {
661 	u_int refs;
662 
663 	KASSERT(solocked(so));
664 
665 	if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) {
666 		sounlock(so);
667 		return;
668 	}
669 	if (so->so_head) {
670 		/*
671 		 * We must not decommission a socket that's on the accept(2)
672 		 * queue.  If we do, then accept(2) may hang after select(2)
673 		 * indicated that the listening socket was ready.
674 		 */
675 		if (!soqremque(so, 0)) {
676 			sounlock(so);
677 			return;
678 		}
679 	}
680 	if (so->so_rcv.sb_hiwat)
681 		(void)chgsbsize(so->so_uidinfo, &so->so_rcv.sb_hiwat, 0,
682 		    RLIM_INFINITY);
683 	if (so->so_snd.sb_hiwat)
684 		(void)chgsbsize(so->so_uidinfo, &so->so_snd.sb_hiwat, 0,
685 		    RLIM_INFINITY);
686 	sbrelease(&so->so_snd, so);
687 	KASSERT(!cv_has_waiters(&so->so_cv));
688 	KASSERT(!cv_has_waiters(&so->so_rcv.sb_cv));
689 	KASSERT(!cv_has_waiters(&so->so_snd.sb_cv));
690 	sorflush(so);
691 	refs = so->so_aborting;	/* XXX */
692 	/* Remove acccept filter if one is present. */
693 	if (so->so_accf != NULL)
694 		(void)accept_filt_clear(so);
695 	sounlock(so);
696 	if (refs == 0)		/* XXX */
697 		soput(so);
698 }
699 
700 /*
701  * Close a socket on last file table reference removal.
702  * Initiate disconnect if connected.
703  * Free socket when disconnect complete.
704  */
705 int
706 soclose(struct socket *so)
707 {
708 	struct socket	*so2;
709 	int		error;
710 	int		error2;
711 
712 	error = 0;
713 	solock(so);
714 	if (so->so_options & SO_ACCEPTCONN) {
715 		for (;;) {
716 			if ((so2 = TAILQ_FIRST(&so->so_q0)) != 0) {
717 				KASSERT(solocked2(so, so2));
718 				(void) soqremque(so2, 0);
719 				/* soabort drops the lock. */
720 				(void) soabort(so2);
721 				solock(so);
722 				continue;
723 			}
724 			if ((so2 = TAILQ_FIRST(&so->so_q)) != 0) {
725 				KASSERT(solocked2(so, so2));
726 				(void) soqremque(so2, 1);
727 				/* soabort drops the lock. */
728 				(void) soabort(so2);
729 				solock(so);
730 				continue;
731 			}
732 			break;
733 		}
734 	}
735 	if (so->so_pcb == 0)
736 		goto discard;
737 	if (so->so_state & SS_ISCONNECTED) {
738 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
739 			error = sodisconnect(so);
740 			if (error)
741 				goto drop;
742 		}
743 		if (so->so_options & SO_LINGER) {
744 			if ((so->so_state & SS_ISDISCONNECTING) && so->so_nbio)
745 				goto drop;
746 			while (so->so_state & SS_ISCONNECTED) {
747 				error = sowait(so, true, so->so_linger * hz);
748 				if (error)
749 					break;
750 			}
751 		}
752 	}
753  drop:
754 	if (so->so_pcb) {
755 		error2 = (*so->so_proto->pr_usrreq)(so, PRU_DETACH,
756 		    NULL, NULL, NULL, NULL);
757 		if (error == 0)
758 			error = error2;
759 	}
760  discard:
761 	if (so->so_state & SS_NOFDREF)
762 		panic("soclose: NOFDREF");
763 	kauth_cred_free(so->so_cred);
764 	so->so_state |= SS_NOFDREF;
765 	sofree(so);
766 	return (error);
767 }
768 
769 /*
770  * Must be called with the socket locked..  Will return with it unlocked.
771  */
772 int
773 soabort(struct socket *so)
774 {
775 	u_int refs;
776 	int error;
777 
778 	KASSERT(solocked(so));
779 	KASSERT(so->so_head == NULL);
780 
781 	so->so_aborting++;		/* XXX */
782 	error = (*so->so_proto->pr_usrreq)(so, PRU_ABORT, NULL,
783 	    NULL, NULL, NULL);
784 	refs = --so->so_aborting;	/* XXX */
785 	if (error || (refs == 0)) {
786 		sofree(so);
787 	} else {
788 		sounlock(so);
789 	}
790 	return error;
791 }
792 
793 int
794 soaccept(struct socket *so, struct mbuf *nam)
795 {
796 	int	error;
797 
798 	KASSERT(solocked(so));
799 
800 	error = 0;
801 	if ((so->so_state & SS_NOFDREF) == 0)
802 		panic("soaccept: !NOFDREF");
803 	so->so_state &= ~SS_NOFDREF;
804 	if ((so->so_state & SS_ISDISCONNECTED) == 0 ||
805 	    (so->so_proto->pr_flags & PR_ABRTACPTDIS) == 0)
806 		error = (*so->so_proto->pr_usrreq)(so, PRU_ACCEPT,
807 		    NULL, nam, NULL, NULL);
808 	else
809 		error = ECONNABORTED;
810 
811 	return (error);
812 }
813 
814 int
815 soconnect(struct socket *so, struct mbuf *nam, struct lwp *l)
816 {
817 	int		error;
818 
819 	KASSERT(solocked(so));
820 
821 	if (so->so_options & SO_ACCEPTCONN)
822 		return (EOPNOTSUPP);
823 	/*
824 	 * If protocol is connection-based, can only connect once.
825 	 * Otherwise, if connected, try to disconnect first.
826 	 * This allows user to disconnect by connecting to, e.g.,
827 	 * a null address.
828 	 */
829 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
830 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
831 	    (error = sodisconnect(so))))
832 		error = EISCONN;
833 	else
834 		error = (*so->so_proto->pr_usrreq)(so, PRU_CONNECT,
835 		    NULL, nam, NULL, l);
836 	return (error);
837 }
838 
839 int
840 soconnect2(struct socket *so1, struct socket *so2)
841 {
842 	int	error;
843 
844 	KASSERT(solocked2(so1, so2));
845 
846 	error = (*so1->so_proto->pr_usrreq)(so1, PRU_CONNECT2,
847 	    NULL, (struct mbuf *)so2, NULL, NULL);
848 	return (error);
849 }
850 
851 int
852 sodisconnect(struct socket *so)
853 {
854 	int	error;
855 
856 	KASSERT(solocked(so));
857 
858 	if ((so->so_state & SS_ISCONNECTED) == 0) {
859 		error = ENOTCONN;
860 	} else if (so->so_state & SS_ISDISCONNECTING) {
861 		error = EALREADY;
862 	} else {
863 		error = (*so->so_proto->pr_usrreq)(so, PRU_DISCONNECT,
864 		    NULL, NULL, NULL, NULL);
865 	}
866 	return (error);
867 }
868 
869 #define	SBLOCKWAIT(f)	(((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
870 /*
871  * Send on a socket.
872  * If send must go all at once and message is larger than
873  * send buffering, then hard error.
874  * Lock against other senders.
875  * If must go all at once and not enough room now, then
876  * inform user that this would block and do nothing.
877  * Otherwise, if nonblocking, send as much as possible.
878  * The data to be sent is described by "uio" if nonzero,
879  * otherwise by the mbuf chain "top" (which must be null
880  * if uio is not).  Data provided in mbuf chain must be small
881  * enough to send all at once.
882  *
883  * Returns nonzero on error, timeout or signal; callers
884  * must check for short counts if EINTR/ERESTART are returned.
885  * Data and control buffers are freed on return.
886  */
887 int
888 sosend(struct socket *so, struct mbuf *addr, struct uio *uio, struct mbuf *top,
889 	struct mbuf *control, int flags, struct lwp *l)
890 {
891 	struct mbuf	**mp, *m;
892 	struct proc	*p;
893 	long		space, len, resid, clen, mlen;
894 	int		error, s, dontroute, atomic;
895 	short		wakeup_state = 0;
896 
897 	p = l->l_proc;
898 	clen = 0;
899 
900 	/*
901 	 * solock() provides atomicity of access.  splsoftnet() prevents
902 	 * protocol processing soft interrupts from interrupting us and
903 	 * blocking (expensive).
904 	 */
905 	s = splsoftnet();
906 	solock(so);
907 	atomic = sosendallatonce(so) || top;
908 	if (uio)
909 		resid = uio->uio_resid;
910 	else
911 		resid = top->m_pkthdr.len;
912 	/*
913 	 * In theory resid should be unsigned.
914 	 * However, space must be signed, as it might be less than 0
915 	 * if we over-committed, and we must use a signed comparison
916 	 * of space and resid.  On the other hand, a negative resid
917 	 * causes us to loop sending 0-length segments to the protocol.
918 	 */
919 	if (resid < 0) {
920 		error = EINVAL;
921 		goto out;
922 	}
923 	dontroute =
924 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
925 	    (so->so_proto->pr_flags & PR_ATOMIC);
926 	l->l_ru.ru_msgsnd++;
927 	if (control)
928 		clen = control->m_len;
929  restart:
930 	if ((error = sblock(&so->so_snd, SBLOCKWAIT(flags))) != 0)
931 		goto out;
932 	do {
933 		if (so->so_state & SS_CANTSENDMORE) {
934 			error = EPIPE;
935 			goto release;
936 		}
937 		if (so->so_error) {
938 			error = so->so_error;
939 			so->so_error = 0;
940 			goto release;
941 		}
942 		if ((so->so_state & SS_ISCONNECTED) == 0) {
943 			if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
944 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
945 				    !(resid == 0 && clen != 0)) {
946 					error = ENOTCONN;
947 					goto release;
948 				}
949 			} else if (addr == 0) {
950 				error = EDESTADDRREQ;
951 				goto release;
952 			}
953 		}
954 		space = sbspace(&so->so_snd);
955 		if (flags & MSG_OOB)
956 			space += 1024;
957 		if ((atomic && resid > so->so_snd.sb_hiwat) ||
958 		    clen > so->so_snd.sb_hiwat) {
959 			error = EMSGSIZE;
960 			goto release;
961 		}
962 		if (space < resid + clen &&
963 		    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
964 			if (so->so_nbio) {
965 				error = EWOULDBLOCK;
966 				goto release;
967 			}
968 			sbunlock(&so->so_snd);
969 			if (wakeup_state & SS_RESTARTSYS) {
970 				error = ERESTART;
971 				goto out;
972 			}
973 			error = sbwait(&so->so_snd);
974 			if (error)
975 				goto out;
976 			wakeup_state = so->so_state;
977 			goto restart;
978 		}
979 		wakeup_state = 0;
980 		mp = &top;
981 		space -= clen;
982 		do {
983 			if (uio == NULL) {
984 				/*
985 				 * Data is prepackaged in "top".
986 				 */
987 				resid = 0;
988 				if (flags & MSG_EOR)
989 					top->m_flags |= M_EOR;
990 			} else do {
991 				sounlock(so);
992 				splx(s);
993 				if (top == NULL) {
994 					m = m_gethdr(M_WAIT, MT_DATA);
995 					mlen = MHLEN;
996 					m->m_pkthdr.len = 0;
997 					m->m_pkthdr.rcvif = NULL;
998 				} else {
999 					m = m_get(M_WAIT, MT_DATA);
1000 					mlen = MLEN;
1001 				}
1002 				MCLAIM(m, so->so_snd.sb_mowner);
1003 				if (sock_loan_thresh >= 0 &&
1004 				    uio->uio_iov->iov_len >= sock_loan_thresh &&
1005 				    space >= sock_loan_thresh &&
1006 				    (len = sosend_loan(so, uio, m,
1007 						       space)) != 0) {
1008 					SOSEND_COUNTER_INCR(&sosend_loan_big);
1009 					space -= len;
1010 					goto have_data;
1011 				}
1012 				if (resid >= MINCLSIZE && space >= MCLBYTES) {
1013 					SOSEND_COUNTER_INCR(&sosend_copy_big);
1014 					m_clget(m, M_DONTWAIT);
1015 					if ((m->m_flags & M_EXT) == 0)
1016 						goto nopages;
1017 					mlen = MCLBYTES;
1018 					if (atomic && top == 0) {
1019 						len = lmin(MCLBYTES - max_hdr,
1020 						    resid);
1021 						m->m_data += max_hdr;
1022 					} else
1023 						len = lmin(MCLBYTES, resid);
1024 					space -= len;
1025 				} else {
1026  nopages:
1027 					SOSEND_COUNTER_INCR(&sosend_copy_small);
1028 					len = lmin(lmin(mlen, resid), space);
1029 					space -= len;
1030 					/*
1031 					 * For datagram protocols, leave room
1032 					 * for protocol headers in first mbuf.
1033 					 */
1034 					if (atomic && top == 0 && len < mlen)
1035 						MH_ALIGN(m, len);
1036 				}
1037 				error = uiomove(mtod(m, void *), (int)len, uio);
1038  have_data:
1039 				resid = uio->uio_resid;
1040 				m->m_len = len;
1041 				*mp = m;
1042 				top->m_pkthdr.len += len;
1043 				s = splsoftnet();
1044 				solock(so);
1045 				if (error != 0)
1046 					goto release;
1047 				mp = &m->m_next;
1048 				if (resid <= 0) {
1049 					if (flags & MSG_EOR)
1050 						top->m_flags |= M_EOR;
1051 					break;
1052 				}
1053 			} while (space > 0 && atomic);
1054 
1055 			if (so->so_state & SS_CANTSENDMORE) {
1056 				error = EPIPE;
1057 				goto release;
1058 			}
1059 			if (dontroute)
1060 				so->so_options |= SO_DONTROUTE;
1061 			if (resid > 0)
1062 				so->so_state |= SS_MORETOCOME;
1063 			error = (*so->so_proto->pr_usrreq)(so,
1064 			    (flags & MSG_OOB) ? PRU_SENDOOB : PRU_SEND,
1065 			    top, addr, control, curlwp);
1066 			if (dontroute)
1067 				so->so_options &= ~SO_DONTROUTE;
1068 			if (resid > 0)
1069 				so->so_state &= ~SS_MORETOCOME;
1070 			clen = 0;
1071 			control = NULL;
1072 			top = NULL;
1073 			mp = &top;
1074 			if (error != 0)
1075 				goto release;
1076 		} while (resid && space > 0);
1077 	} while (resid);
1078 
1079  release:
1080 	sbunlock(&so->so_snd);
1081  out:
1082 	sounlock(so);
1083 	splx(s);
1084 	if (top)
1085 		m_freem(top);
1086 	if (control)
1087 		m_freem(control);
1088 	return (error);
1089 }
1090 
1091 /*
1092  * Following replacement or removal of the first mbuf on the first
1093  * mbuf chain of a socket buffer, push necessary state changes back
1094  * into the socket buffer so that other consumers see the values
1095  * consistently.  'nextrecord' is the callers locally stored value of
1096  * the original value of sb->sb_mb->m_nextpkt which must be restored
1097  * when the lead mbuf changes.  NOTE: 'nextrecord' may be NULL.
1098  */
1099 static void
1100 sbsync(struct sockbuf *sb, struct mbuf *nextrecord)
1101 {
1102 
1103 	KASSERT(solocked(sb->sb_so));
1104 
1105 	/*
1106 	 * First, update for the new value of nextrecord.  If necessary,
1107 	 * make it the first record.
1108 	 */
1109 	if (sb->sb_mb != NULL)
1110 		sb->sb_mb->m_nextpkt = nextrecord;
1111 	else
1112 		sb->sb_mb = nextrecord;
1113 
1114         /*
1115          * Now update any dependent socket buffer fields to reflect
1116          * the new state.  This is an inline of SB_EMPTY_FIXUP, with
1117          * the addition of a second clause that takes care of the
1118          * case where sb_mb has been updated, but remains the last
1119          * record.
1120          */
1121         if (sb->sb_mb == NULL) {
1122                 sb->sb_mbtail = NULL;
1123                 sb->sb_lastrecord = NULL;
1124         } else if (sb->sb_mb->m_nextpkt == NULL)
1125                 sb->sb_lastrecord = sb->sb_mb;
1126 }
1127 
1128 /*
1129  * Implement receive operations on a socket.
1130  * We depend on the way that records are added to the sockbuf
1131  * by sbappend*.  In particular, each record (mbufs linked through m_next)
1132  * must begin with an address if the protocol so specifies,
1133  * followed by an optional mbuf or mbufs containing ancillary data,
1134  * and then zero or more mbufs of data.
1135  * In order to avoid blocking network interrupts for the entire time here,
1136  * we splx() while doing the actual copy to user space.
1137  * Although the sockbuf is locked, new data may still be appended,
1138  * and thus we must maintain consistency of the sockbuf during that time.
1139  *
1140  * The caller may receive the data as a single mbuf chain by supplying
1141  * an mbuf **mp0 for use in returning the chain.  The uio is then used
1142  * only for the count in uio_resid.
1143  */
1144 int
1145 soreceive(struct socket *so, struct mbuf **paddr, struct uio *uio,
1146 	struct mbuf **mp0, struct mbuf **controlp, int *flagsp)
1147 {
1148 	struct lwp *l = curlwp;
1149 	struct mbuf	*m, **mp, *mt;
1150 	int atomic, flags, len, error, s, offset, moff, type, orig_resid;
1151 	const struct protosw	*pr;
1152 	struct mbuf	*nextrecord;
1153 	int		mbuf_removed = 0;
1154 	const struct domain *dom;
1155 	short		wakeup_state = 0;
1156 
1157 	pr = so->so_proto;
1158 	atomic = pr->pr_flags & PR_ATOMIC;
1159 	dom = pr->pr_domain;
1160 	mp = mp0;
1161 	type = 0;
1162 	orig_resid = uio->uio_resid;
1163 
1164 	if (paddr != NULL)
1165 		*paddr = NULL;
1166 	if (controlp != NULL)
1167 		*controlp = NULL;
1168 	if (flagsp != NULL)
1169 		flags = *flagsp &~ MSG_EOR;
1170 	else
1171 		flags = 0;
1172 
1173 	if (flags & MSG_OOB) {
1174 		m = m_get(M_WAIT, MT_DATA);
1175 		solock(so);
1176 		error = (*pr->pr_usrreq)(so, PRU_RCVOOB, m,
1177 		    (struct mbuf *)(long)(flags & MSG_PEEK), NULL, l);
1178 		sounlock(so);
1179 		if (error)
1180 			goto bad;
1181 		do {
1182 			error = uiomove(mtod(m, void *),
1183 			    (int) min(uio->uio_resid, m->m_len), uio);
1184 			m = m_free(m);
1185 		} while (uio->uio_resid > 0 && error == 0 && m);
1186  bad:
1187 		if (m != NULL)
1188 			m_freem(m);
1189 		return error;
1190 	}
1191 	if (mp != NULL)
1192 		*mp = NULL;
1193 
1194 	/*
1195 	 * solock() provides atomicity of access.  splsoftnet() prevents
1196 	 * protocol processing soft interrupts from interrupting us and
1197 	 * blocking (expensive).
1198 	 */
1199 	s = splsoftnet();
1200 	solock(so);
1201 	if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
1202 		(*pr->pr_usrreq)(so, PRU_RCVD, NULL, NULL, NULL, l);
1203 
1204  restart:
1205 	if ((error = sblock(&so->so_rcv, SBLOCKWAIT(flags))) != 0) {
1206 		sounlock(so);
1207 		splx(s);
1208 		return error;
1209 	}
1210 
1211 	m = so->so_rcv.sb_mb;
1212 	/*
1213 	 * If we have less data than requested, block awaiting more
1214 	 * (subject to any timeout) if:
1215 	 *   1. the current count is less than the low water mark,
1216 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
1217 	 *	receive operation at once if we block (resid <= hiwat), or
1218 	 *   3. MSG_DONTWAIT is not set.
1219 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1220 	 * we have to do the receive in sections, and thus risk returning
1221 	 * a short count if a timeout or signal occurs after we start.
1222 	 */
1223 	if (m == NULL ||
1224 	    ((flags & MSG_DONTWAIT) == 0 &&
1225 	     so->so_rcv.sb_cc < uio->uio_resid &&
1226 	     (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
1227 	      ((flags & MSG_WAITALL) &&
1228 	       uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
1229 	     m->m_nextpkt == NULL && !atomic)) {
1230 #ifdef DIAGNOSTIC
1231 		if (m == NULL && so->so_rcv.sb_cc)
1232 			panic("receive 1");
1233 #endif
1234 		if (so->so_error) {
1235 			if (m != NULL)
1236 				goto dontblock;
1237 			error = so->so_error;
1238 			if ((flags & MSG_PEEK) == 0)
1239 				so->so_error = 0;
1240 			goto release;
1241 		}
1242 		if (so->so_state & SS_CANTRCVMORE) {
1243 			if (m != NULL)
1244 				goto dontblock;
1245 			else
1246 				goto release;
1247 		}
1248 		for (; m != NULL; m = m->m_next)
1249 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
1250 				m = so->so_rcv.sb_mb;
1251 				goto dontblock;
1252 			}
1253 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1254 		    (so->so_proto->pr_flags & PR_CONNREQUIRED)) {
1255 			error = ENOTCONN;
1256 			goto release;
1257 		}
1258 		if (uio->uio_resid == 0)
1259 			goto release;
1260 		if (so->so_nbio || (flags & MSG_DONTWAIT)) {
1261 			error = EWOULDBLOCK;
1262 			goto release;
1263 		}
1264 		SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 1");
1265 		SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 1");
1266 		sbunlock(&so->so_rcv);
1267 		if (wakeup_state & SS_RESTARTSYS)
1268 			error = ERESTART;
1269 		else
1270 			error = sbwait(&so->so_rcv);
1271 		if (error != 0) {
1272 			sounlock(so);
1273 			splx(s);
1274 			return error;
1275 		}
1276 		wakeup_state = so->so_state;
1277 		goto restart;
1278 	}
1279  dontblock:
1280 	/*
1281 	 * On entry here, m points to the first record of the socket buffer.
1282 	 * From this point onward, we maintain 'nextrecord' as a cache of the
1283 	 * pointer to the next record in the socket buffer.  We must keep the
1284 	 * various socket buffer pointers and local stack versions of the
1285 	 * pointers in sync, pushing out modifications before dropping the
1286 	 * socket lock, and re-reading them when picking it up.
1287 	 *
1288 	 * Otherwise, we will race with the network stack appending new data
1289 	 * or records onto the socket buffer by using inconsistent/stale
1290 	 * versions of the field, possibly resulting in socket buffer
1291 	 * corruption.
1292 	 *
1293 	 * By holding the high-level sblock(), we prevent simultaneous
1294 	 * readers from pulling off the front of the socket buffer.
1295 	 */
1296 	if (l != NULL)
1297 		l->l_ru.ru_msgrcv++;
1298 	KASSERT(m == so->so_rcv.sb_mb);
1299 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 1");
1300 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 1");
1301 	nextrecord = m->m_nextpkt;
1302 	if (pr->pr_flags & PR_ADDR) {
1303 #ifdef DIAGNOSTIC
1304 		if (m->m_type != MT_SONAME)
1305 			panic("receive 1a");
1306 #endif
1307 		orig_resid = 0;
1308 		if (flags & MSG_PEEK) {
1309 			if (paddr)
1310 				*paddr = m_copy(m, 0, m->m_len);
1311 			m = m->m_next;
1312 		} else {
1313 			sbfree(&so->so_rcv, m);
1314 			mbuf_removed = 1;
1315 			if (paddr != NULL) {
1316 				*paddr = m;
1317 				so->so_rcv.sb_mb = m->m_next;
1318 				m->m_next = NULL;
1319 				m = so->so_rcv.sb_mb;
1320 			} else {
1321 				MFREE(m, so->so_rcv.sb_mb);
1322 				m = so->so_rcv.sb_mb;
1323 			}
1324 			sbsync(&so->so_rcv, nextrecord);
1325 		}
1326 	}
1327 
1328 	/*
1329 	 * Process one or more MT_CONTROL mbufs present before any data mbufs
1330 	 * in the first mbuf chain on the socket buffer.  If MSG_PEEK, we
1331 	 * just copy the data; if !MSG_PEEK, we call into the protocol to
1332 	 * perform externalization (or freeing if controlp == NULL).
1333 	 */
1334 	if (__predict_false(m != NULL && m->m_type == MT_CONTROL)) {
1335 		struct mbuf *cm = NULL, *cmn;
1336 		struct mbuf **cme = &cm;
1337 
1338 		do {
1339 			if (flags & MSG_PEEK) {
1340 				if (controlp != NULL) {
1341 					*controlp = m_copy(m, 0, m->m_len);
1342 					controlp = &(*controlp)->m_next;
1343 				}
1344 				m = m->m_next;
1345 			} else {
1346 				sbfree(&so->so_rcv, m);
1347 				so->so_rcv.sb_mb = m->m_next;
1348 				m->m_next = NULL;
1349 				*cme = m;
1350 				cme = &(*cme)->m_next;
1351 				m = so->so_rcv.sb_mb;
1352 			}
1353 		} while (m != NULL && m->m_type == MT_CONTROL);
1354 		if ((flags & MSG_PEEK) == 0)
1355 			sbsync(&so->so_rcv, nextrecord);
1356 		for (; cm != NULL; cm = cmn) {
1357 			cmn = cm->m_next;
1358 			cm->m_next = NULL;
1359 			type = mtod(cm, struct cmsghdr *)->cmsg_type;
1360 			if (controlp != NULL) {
1361 				if (dom->dom_externalize != NULL &&
1362 				    type == SCM_RIGHTS) {
1363 					sounlock(so);
1364 					splx(s);
1365 					error = (*dom->dom_externalize)(cm, l,
1366 					    (flags & MSG_CMSG_CLOEXEC) ?
1367 					    O_CLOEXEC : 0);
1368 					s = splsoftnet();
1369 					solock(so);
1370 				}
1371 				*controlp = cm;
1372 				while (*controlp != NULL)
1373 					controlp = &(*controlp)->m_next;
1374 			} else {
1375 				/*
1376 				 * Dispose of any SCM_RIGHTS message that went
1377 				 * through the read path rather than recv.
1378 				 */
1379 				if (dom->dom_dispose != NULL &&
1380 				    type == SCM_RIGHTS) {
1381 				    	sounlock(so);
1382 					(*dom->dom_dispose)(cm);
1383 					solock(so);
1384 				}
1385 				m_freem(cm);
1386 			}
1387 		}
1388 		if (m != NULL)
1389 			nextrecord = so->so_rcv.sb_mb->m_nextpkt;
1390 		else
1391 			nextrecord = so->so_rcv.sb_mb;
1392 		orig_resid = 0;
1393 	}
1394 
1395 	/* If m is non-NULL, we have some data to read. */
1396 	if (__predict_true(m != NULL)) {
1397 		type = m->m_type;
1398 		if (type == MT_OOBDATA)
1399 			flags |= MSG_OOB;
1400 	}
1401 	SBLASTRECORDCHK(&so->so_rcv, "soreceive 2");
1402 	SBLASTMBUFCHK(&so->so_rcv, "soreceive 2");
1403 
1404 	moff = 0;
1405 	offset = 0;
1406 	while (m != NULL && uio->uio_resid > 0 && error == 0) {
1407 		if (m->m_type == MT_OOBDATA) {
1408 			if (type != MT_OOBDATA)
1409 				break;
1410 		} else if (type == MT_OOBDATA)
1411 			break;
1412 #ifdef DIAGNOSTIC
1413 		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
1414 			panic("receive 3");
1415 #endif
1416 		so->so_state &= ~SS_RCVATMARK;
1417 		wakeup_state = 0;
1418 		len = uio->uio_resid;
1419 		if (so->so_oobmark && len > so->so_oobmark - offset)
1420 			len = so->so_oobmark - offset;
1421 		if (len > m->m_len - moff)
1422 			len = m->m_len - moff;
1423 		/*
1424 		 * If mp is set, just pass back the mbufs.
1425 		 * Otherwise copy them out via the uio, then free.
1426 		 * Sockbuf must be consistent here (points to current mbuf,
1427 		 * it points to next record) when we drop priority;
1428 		 * we must note any additions to the sockbuf when we
1429 		 * block interrupts again.
1430 		 */
1431 		if (mp == NULL) {
1432 			SBLASTRECORDCHK(&so->so_rcv, "soreceive uiomove");
1433 			SBLASTMBUFCHK(&so->so_rcv, "soreceive uiomove");
1434 			sounlock(so);
1435 			splx(s);
1436 			error = uiomove(mtod(m, char *) + moff, (int)len, uio);
1437 			s = splsoftnet();
1438 			solock(so);
1439 			if (error != 0) {
1440 				/*
1441 				 * If any part of the record has been removed
1442 				 * (such as the MT_SONAME mbuf, which will
1443 				 * happen when PR_ADDR, and thus also
1444 				 * PR_ATOMIC, is set), then drop the entire
1445 				 * record to maintain the atomicity of the
1446 				 * receive operation.
1447 				 *
1448 				 * This avoids a later panic("receive 1a")
1449 				 * when compiled with DIAGNOSTIC.
1450 				 */
1451 				if (m && mbuf_removed && atomic)
1452 					(void) sbdroprecord(&so->so_rcv);
1453 
1454 				goto release;
1455 			}
1456 		} else
1457 			uio->uio_resid -= len;
1458 		if (len == m->m_len - moff) {
1459 			if (m->m_flags & M_EOR)
1460 				flags |= MSG_EOR;
1461 			if (flags & MSG_PEEK) {
1462 				m = m->m_next;
1463 				moff = 0;
1464 			} else {
1465 				nextrecord = m->m_nextpkt;
1466 				sbfree(&so->so_rcv, m);
1467 				if (mp) {
1468 					*mp = m;
1469 					mp = &m->m_next;
1470 					so->so_rcv.sb_mb = m = m->m_next;
1471 					*mp = NULL;
1472 				} else {
1473 					MFREE(m, so->so_rcv.sb_mb);
1474 					m = so->so_rcv.sb_mb;
1475 				}
1476 				/*
1477 				 * If m != NULL, we also know that
1478 				 * so->so_rcv.sb_mb != NULL.
1479 				 */
1480 				KASSERT(so->so_rcv.sb_mb == m);
1481 				if (m) {
1482 					m->m_nextpkt = nextrecord;
1483 					if (nextrecord == NULL)
1484 						so->so_rcv.sb_lastrecord = m;
1485 				} else {
1486 					so->so_rcv.sb_mb = nextrecord;
1487 					SB_EMPTY_FIXUP(&so->so_rcv);
1488 				}
1489 				SBLASTRECORDCHK(&so->so_rcv, "soreceive 3");
1490 				SBLASTMBUFCHK(&so->so_rcv, "soreceive 3");
1491 			}
1492 		} else if (flags & MSG_PEEK)
1493 			moff += len;
1494 		else {
1495 			if (mp != NULL) {
1496 				mt = m_copym(m, 0, len, M_NOWAIT);
1497 				if (__predict_false(mt == NULL)) {
1498 					sounlock(so);
1499 					mt = m_copym(m, 0, len, M_WAIT);
1500 					solock(so);
1501 				}
1502 				*mp = mt;
1503 			}
1504 			m->m_data += len;
1505 			m->m_len -= len;
1506 			so->so_rcv.sb_cc -= len;
1507 		}
1508 		if (so->so_oobmark) {
1509 			if ((flags & MSG_PEEK) == 0) {
1510 				so->so_oobmark -= len;
1511 				if (so->so_oobmark == 0) {
1512 					so->so_state |= SS_RCVATMARK;
1513 					break;
1514 				}
1515 			} else {
1516 				offset += len;
1517 				if (offset == so->so_oobmark)
1518 					break;
1519 			}
1520 		}
1521 		if (flags & MSG_EOR)
1522 			break;
1523 		/*
1524 		 * If the MSG_WAITALL flag is set (for non-atomic socket),
1525 		 * we must not quit until "uio->uio_resid == 0" or an error
1526 		 * termination.  If a signal/timeout occurs, return
1527 		 * with a short count but without error.
1528 		 * Keep sockbuf locked against other readers.
1529 		 */
1530 		while (flags & MSG_WAITALL && m == NULL && uio->uio_resid > 0 &&
1531 		    !sosendallatonce(so) && !nextrecord) {
1532 			if (so->so_error || so->so_state & SS_CANTRCVMORE)
1533 				break;
1534 			/*
1535 			 * If we are peeking and the socket receive buffer is
1536 			 * full, stop since we can't get more data to peek at.
1537 			 */
1538 			if ((flags & MSG_PEEK) && sbspace(&so->so_rcv) <= 0)
1539 				break;
1540 			/*
1541 			 * If we've drained the socket buffer, tell the
1542 			 * protocol in case it needs to do something to
1543 			 * get it filled again.
1544 			 */
1545 			if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb)
1546 				(*pr->pr_usrreq)(so, PRU_RCVD,
1547 				    NULL, (struct mbuf *)(long)flags, NULL, l);
1548 			SBLASTRECORDCHK(&so->so_rcv, "soreceive sbwait 2");
1549 			SBLASTMBUFCHK(&so->so_rcv, "soreceive sbwait 2");
1550 			if (wakeup_state & SS_RESTARTSYS)
1551 				error = ERESTART;
1552 			else
1553 				error = sbwait(&so->so_rcv);
1554 			if (error != 0) {
1555 				sbunlock(&so->so_rcv);
1556 				sounlock(so);
1557 				splx(s);
1558 				return 0;
1559 			}
1560 			if ((m = so->so_rcv.sb_mb) != NULL)
1561 				nextrecord = m->m_nextpkt;
1562 			wakeup_state = so->so_state;
1563 		}
1564 	}
1565 
1566 	if (m && atomic) {
1567 		flags |= MSG_TRUNC;
1568 		if ((flags & MSG_PEEK) == 0)
1569 			(void) sbdroprecord(&so->so_rcv);
1570 	}
1571 	if ((flags & MSG_PEEK) == 0) {
1572 		if (m == NULL) {
1573 			/*
1574 			 * First part is an inline SB_EMPTY_FIXUP().  Second
1575 			 * part makes sure sb_lastrecord is up-to-date if
1576 			 * there is still data in the socket buffer.
1577 			 */
1578 			so->so_rcv.sb_mb = nextrecord;
1579 			if (so->so_rcv.sb_mb == NULL) {
1580 				so->so_rcv.sb_mbtail = NULL;
1581 				so->so_rcv.sb_lastrecord = NULL;
1582 			} else if (nextrecord->m_nextpkt == NULL)
1583 				so->so_rcv.sb_lastrecord = nextrecord;
1584 		}
1585 		SBLASTRECORDCHK(&so->so_rcv, "soreceive 4");
1586 		SBLASTMBUFCHK(&so->so_rcv, "soreceive 4");
1587 		if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1588 			(*pr->pr_usrreq)(so, PRU_RCVD, NULL,
1589 			    (struct mbuf *)(long)flags, NULL, l);
1590 	}
1591 	if (orig_resid == uio->uio_resid && orig_resid &&
1592 	    (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
1593 		sbunlock(&so->so_rcv);
1594 		goto restart;
1595 	}
1596 
1597 	if (flagsp != NULL)
1598 		*flagsp |= flags;
1599  release:
1600 	sbunlock(&so->so_rcv);
1601 	sounlock(so);
1602 	splx(s);
1603 	return error;
1604 }
1605 
1606 int
1607 soshutdown(struct socket *so, int how)
1608 {
1609 	const struct protosw	*pr;
1610 	int	error;
1611 
1612 	KASSERT(solocked(so));
1613 
1614 	pr = so->so_proto;
1615 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
1616 		return (EINVAL);
1617 
1618 	if (how == SHUT_RD || how == SHUT_RDWR) {
1619 		sorflush(so);
1620 		error = 0;
1621 	}
1622 	if (how == SHUT_WR || how == SHUT_RDWR)
1623 		error = (*pr->pr_usrreq)(so, PRU_SHUTDOWN, NULL,
1624 		    NULL, NULL, NULL);
1625 
1626 	return error;
1627 }
1628 
1629 void
1630 sorestart(struct socket *so)
1631 {
1632 	/*
1633 	 * An application has called close() on an fd on which another
1634 	 * of its threads has called a socket system call.
1635 	 * Mark this and wake everyone up, and code that would block again
1636 	 * instead returns ERESTART.
1637 	 * On system call re-entry the fd is validated and EBADF returned.
1638 	 * Any other fd will block again on the 2nd syscall.
1639 	 */
1640 	solock(so);
1641 	so->so_state |= SS_RESTARTSYS;
1642 	cv_broadcast(&so->so_cv);
1643 	cv_broadcast(&so->so_snd.sb_cv);
1644 	cv_broadcast(&so->so_rcv.sb_cv);
1645 	sounlock(so);
1646 }
1647 
1648 void
1649 sorflush(struct socket *so)
1650 {
1651 	struct sockbuf	*sb, asb;
1652 	const struct protosw	*pr;
1653 
1654 	KASSERT(solocked(so));
1655 
1656 	sb = &so->so_rcv;
1657 	pr = so->so_proto;
1658 	socantrcvmore(so);
1659 	sb->sb_flags |= SB_NOINTR;
1660 	(void )sblock(sb, M_WAITOK);
1661 	sbunlock(sb);
1662 	asb = *sb;
1663 	/*
1664 	 * Clear most of the sockbuf structure, but leave some of the
1665 	 * fields valid.
1666 	 */
1667 	memset(&sb->sb_startzero, 0,
1668 	    sizeof(*sb) - offsetof(struct sockbuf, sb_startzero));
1669 	if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) {
1670 		sounlock(so);
1671 		(*pr->pr_domain->dom_dispose)(asb.sb_mb);
1672 		solock(so);
1673 	}
1674 	sbrelease(&asb, so);
1675 }
1676 
1677 /*
1678  * internal set SOL_SOCKET options
1679  */
1680 static int
1681 sosetopt1(struct socket *so, const struct sockopt *sopt)
1682 {
1683 	int error = EINVAL, optval, opt;
1684 	struct linger l;
1685 	struct timeval tv;
1686 
1687 	switch ((opt = sopt->sopt_name)) {
1688 
1689 	case SO_ACCEPTFILTER:
1690 		error = accept_filt_setopt(so, sopt);
1691 		KASSERT(solocked(so));
1692 		break;
1693 
1694   	case SO_LINGER:
1695  		error = sockopt_get(sopt, &l, sizeof(l));
1696 		solock(so);
1697  		if (error)
1698  			break;
1699  		if (l.l_linger < 0 || l.l_linger > USHRT_MAX ||
1700  		    l.l_linger > (INT_MAX / hz)) {
1701 			error = EDOM;
1702 			break;
1703 		}
1704  		so->so_linger = l.l_linger;
1705  		if (l.l_onoff)
1706  			so->so_options |= SO_LINGER;
1707  		else
1708  			so->so_options &= ~SO_LINGER;
1709    		break;
1710 
1711 	case SO_DEBUG:
1712 	case SO_KEEPALIVE:
1713 	case SO_DONTROUTE:
1714 	case SO_USELOOPBACK:
1715 	case SO_BROADCAST:
1716 	case SO_REUSEADDR:
1717 	case SO_REUSEPORT:
1718 	case SO_OOBINLINE:
1719 	case SO_TIMESTAMP:
1720 #ifdef SO_OTIMESTAMP
1721 	case SO_OTIMESTAMP:
1722 #endif
1723 		error = sockopt_getint(sopt, &optval);
1724 		solock(so);
1725 		if (error)
1726 			break;
1727 		if (optval)
1728 			so->so_options |= opt;
1729 		else
1730 			so->so_options &= ~opt;
1731 		break;
1732 
1733 	case SO_SNDBUF:
1734 	case SO_RCVBUF:
1735 	case SO_SNDLOWAT:
1736 	case SO_RCVLOWAT:
1737 		error = sockopt_getint(sopt, &optval);
1738 		solock(so);
1739 		if (error)
1740 			break;
1741 
1742 		/*
1743 		 * Values < 1 make no sense for any of these
1744 		 * options, so disallow them.
1745 		 */
1746 		if (optval < 1) {
1747 			error = EINVAL;
1748 			break;
1749 		}
1750 
1751 		switch (opt) {
1752 		case SO_SNDBUF:
1753 			if (sbreserve(&so->so_snd, (u_long)optval, so) == 0) {
1754 				error = ENOBUFS;
1755 				break;
1756 			}
1757 			so->so_snd.sb_flags &= ~SB_AUTOSIZE;
1758 			break;
1759 
1760 		case SO_RCVBUF:
1761 			if (sbreserve(&so->so_rcv, (u_long)optval, so) == 0) {
1762 				error = ENOBUFS;
1763 				break;
1764 			}
1765 			so->so_rcv.sb_flags &= ~SB_AUTOSIZE;
1766 			break;
1767 
1768 		/*
1769 		 * Make sure the low-water is never greater than
1770 		 * the high-water.
1771 		 */
1772 		case SO_SNDLOWAT:
1773 			if (optval > so->so_snd.sb_hiwat)
1774 				optval = so->so_snd.sb_hiwat;
1775 
1776 			so->so_snd.sb_lowat = optval;
1777 			break;
1778 
1779 		case SO_RCVLOWAT:
1780 			if (optval > so->so_rcv.sb_hiwat)
1781 				optval = so->so_rcv.sb_hiwat;
1782 
1783 			so->so_rcv.sb_lowat = optval;
1784 			break;
1785 		}
1786 		break;
1787 
1788 #ifdef COMPAT_50
1789 	case SO_OSNDTIMEO:
1790 	case SO_ORCVTIMEO: {
1791 		struct timeval50 otv;
1792 		error = sockopt_get(sopt, &otv, sizeof(otv));
1793 		if (error) {
1794 			solock(so);
1795 			break;
1796 		}
1797 		timeval50_to_timeval(&otv, &tv);
1798 		opt = opt == SO_OSNDTIMEO ? SO_SNDTIMEO : SO_RCVTIMEO;
1799 		error = 0;
1800 		/*FALLTHROUGH*/
1801 	}
1802 #endif /* COMPAT_50 */
1803 
1804 	case SO_SNDTIMEO:
1805 	case SO_RCVTIMEO:
1806 		if (error)
1807 			error = sockopt_get(sopt, &tv, sizeof(tv));
1808 		solock(so);
1809 		if (error)
1810 			break;
1811 
1812 		if (tv.tv_sec > (INT_MAX - tv.tv_usec / tick) / hz) {
1813 			error = EDOM;
1814 			break;
1815 		}
1816 
1817 		optval = tv.tv_sec * hz + tv.tv_usec / tick;
1818 		if (optval == 0 && tv.tv_usec != 0)
1819 			optval = 1;
1820 
1821 		switch (opt) {
1822 		case SO_SNDTIMEO:
1823 			so->so_snd.sb_timeo = optval;
1824 			break;
1825 		case SO_RCVTIMEO:
1826 			so->so_rcv.sb_timeo = optval;
1827 			break;
1828 		}
1829 		break;
1830 
1831 	default:
1832 		solock(so);
1833 		error = ENOPROTOOPT;
1834 		break;
1835 	}
1836 	KASSERT(solocked(so));
1837 	return error;
1838 }
1839 
1840 int
1841 sosetopt(struct socket *so, struct sockopt *sopt)
1842 {
1843 	int error, prerr;
1844 
1845 	if (sopt->sopt_level == SOL_SOCKET) {
1846 		error = sosetopt1(so, sopt);
1847 		KASSERT(solocked(so));
1848 	} else {
1849 		error = ENOPROTOOPT;
1850 		solock(so);
1851 	}
1852 
1853 	if ((error == 0 || error == ENOPROTOOPT) &&
1854 	    so->so_proto != NULL && so->so_proto->pr_ctloutput != NULL) {
1855 		/* give the protocol stack a shot */
1856 		prerr = (*so->so_proto->pr_ctloutput)(PRCO_SETOPT, so, sopt);
1857 		if (prerr == 0)
1858 			error = 0;
1859 		else if (prerr != ENOPROTOOPT)
1860 			error = prerr;
1861 	}
1862 	sounlock(so);
1863 	return error;
1864 }
1865 
1866 /*
1867  * so_setsockopt() is a wrapper providing a sockopt structure for sosetopt()
1868  */
1869 int
1870 so_setsockopt(struct lwp *l, struct socket *so, int level, int name,
1871     const void *val, size_t valsize)
1872 {
1873 	struct sockopt sopt;
1874 	int error;
1875 
1876 	KASSERT(valsize == 0 || val != NULL);
1877 
1878 	sockopt_init(&sopt, level, name, valsize);
1879 	sockopt_set(&sopt, val, valsize);
1880 
1881 	error = sosetopt(so, &sopt);
1882 
1883 	sockopt_destroy(&sopt);
1884 
1885 	return error;
1886 }
1887 
1888 /*
1889  * internal get SOL_SOCKET options
1890  */
1891 static int
1892 sogetopt1(struct socket *so, struct sockopt *sopt)
1893 {
1894 	int error, optval, opt;
1895 	struct linger l;
1896 	struct timeval tv;
1897 
1898 	switch ((opt = sopt->sopt_name)) {
1899 
1900 	case SO_ACCEPTFILTER:
1901 		error = accept_filt_getopt(so, sopt);
1902 		break;
1903 
1904 	case SO_LINGER:
1905 		l.l_onoff = (so->so_options & SO_LINGER) ? 1 : 0;
1906 		l.l_linger = so->so_linger;
1907 
1908 		error = sockopt_set(sopt, &l, sizeof(l));
1909 		break;
1910 
1911 	case SO_USELOOPBACK:
1912 	case SO_DONTROUTE:
1913 	case SO_DEBUG:
1914 	case SO_KEEPALIVE:
1915 	case SO_REUSEADDR:
1916 	case SO_REUSEPORT:
1917 	case SO_BROADCAST:
1918 	case SO_OOBINLINE:
1919 	case SO_TIMESTAMP:
1920 #ifdef SO_OTIMESTAMP
1921 	case SO_OTIMESTAMP:
1922 #endif
1923 		error = sockopt_setint(sopt, (so->so_options & opt) ? 1 : 0);
1924 		break;
1925 
1926 	case SO_TYPE:
1927 		error = sockopt_setint(sopt, so->so_type);
1928 		break;
1929 
1930 	case SO_ERROR:
1931 		error = sockopt_setint(sopt, so->so_error);
1932 		so->so_error = 0;
1933 		break;
1934 
1935 	case SO_SNDBUF:
1936 		error = sockopt_setint(sopt, so->so_snd.sb_hiwat);
1937 		break;
1938 
1939 	case SO_RCVBUF:
1940 		error = sockopt_setint(sopt, so->so_rcv.sb_hiwat);
1941 		break;
1942 
1943 	case SO_SNDLOWAT:
1944 		error = sockopt_setint(sopt, so->so_snd.sb_lowat);
1945 		break;
1946 
1947 	case SO_RCVLOWAT:
1948 		error = sockopt_setint(sopt, so->so_rcv.sb_lowat);
1949 		break;
1950 
1951 #ifdef COMPAT_50
1952 	case SO_OSNDTIMEO:
1953 	case SO_ORCVTIMEO: {
1954 		struct timeval50 otv;
1955 
1956 		optval = (opt == SO_OSNDTIMEO ?
1957 		     so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
1958 
1959 		otv.tv_sec = optval / hz;
1960 		otv.tv_usec = (optval % hz) * tick;
1961 
1962 		error = sockopt_set(sopt, &otv, sizeof(otv));
1963 		break;
1964 	}
1965 #endif /* COMPAT_50 */
1966 
1967 	case SO_SNDTIMEO:
1968 	case SO_RCVTIMEO:
1969 		optval = (opt == SO_SNDTIMEO ?
1970 		     so->so_snd.sb_timeo : so->so_rcv.sb_timeo);
1971 
1972 		tv.tv_sec = optval / hz;
1973 		tv.tv_usec = (optval % hz) * tick;
1974 
1975 		error = sockopt_set(sopt, &tv, sizeof(tv));
1976 		break;
1977 
1978 	case SO_OVERFLOWED:
1979 		error = sockopt_setint(sopt, so->so_rcv.sb_overflowed);
1980 		break;
1981 
1982 	default:
1983 		error = ENOPROTOOPT;
1984 		break;
1985 	}
1986 
1987 	return (error);
1988 }
1989 
1990 int
1991 sogetopt(struct socket *so, struct sockopt *sopt)
1992 {
1993 	int		error;
1994 
1995 	solock(so);
1996 	if (sopt->sopt_level != SOL_SOCKET) {
1997 		if (so->so_proto && so->so_proto->pr_ctloutput) {
1998 			error = ((*so->so_proto->pr_ctloutput)
1999 			    (PRCO_GETOPT, so, sopt));
2000 		} else
2001 			error = (ENOPROTOOPT);
2002 	} else {
2003 		error = sogetopt1(so, sopt);
2004 	}
2005 	sounlock(so);
2006 	return (error);
2007 }
2008 
2009 /*
2010  * alloc sockopt data buffer buffer
2011  *	- will be released at destroy
2012  */
2013 static int
2014 sockopt_alloc(struct sockopt *sopt, size_t len, km_flag_t kmflag)
2015 {
2016 
2017 	KASSERT(sopt->sopt_size == 0);
2018 
2019 	if (len > sizeof(sopt->sopt_buf)) {
2020 		sopt->sopt_data = kmem_zalloc(len, kmflag);
2021 		if (sopt->sopt_data == NULL)
2022 			return ENOMEM;
2023 	} else
2024 		sopt->sopt_data = sopt->sopt_buf;
2025 
2026 	sopt->sopt_size = len;
2027 	return 0;
2028 }
2029 
2030 /*
2031  * initialise sockopt storage
2032  *	- MAY sleep during allocation
2033  */
2034 void
2035 sockopt_init(struct sockopt *sopt, int level, int name, size_t size)
2036 {
2037 
2038 	memset(sopt, 0, sizeof(*sopt));
2039 
2040 	sopt->sopt_level = level;
2041 	sopt->sopt_name = name;
2042 	(void)sockopt_alloc(sopt, size, KM_SLEEP);
2043 }
2044 
2045 /*
2046  * destroy sockopt storage
2047  *	- will release any held memory references
2048  */
2049 void
2050 sockopt_destroy(struct sockopt *sopt)
2051 {
2052 
2053 	if (sopt->sopt_data != sopt->sopt_buf)
2054 		kmem_free(sopt->sopt_data, sopt->sopt_size);
2055 
2056 	memset(sopt, 0, sizeof(*sopt));
2057 }
2058 
2059 /*
2060  * set sockopt value
2061  *	- value is copied into sockopt
2062  * 	- memory is allocated when necessary, will not sleep
2063  */
2064 int
2065 sockopt_set(struct sockopt *sopt, const void *buf, size_t len)
2066 {
2067 	int error;
2068 
2069 	if (sopt->sopt_size == 0) {
2070 		error = sockopt_alloc(sopt, len, KM_NOSLEEP);
2071 		if (error)
2072 			return error;
2073 	}
2074 
2075 	KASSERT(sopt->sopt_size == len);
2076 	memcpy(sopt->sopt_data, buf, len);
2077 	return 0;
2078 }
2079 
2080 /*
2081  * common case of set sockopt integer value
2082  */
2083 int
2084 sockopt_setint(struct sockopt *sopt, int val)
2085 {
2086 
2087 	return sockopt_set(sopt, &val, sizeof(int));
2088 }
2089 
2090 /*
2091  * get sockopt value
2092  *	- correct size must be given
2093  */
2094 int
2095 sockopt_get(const struct sockopt *sopt, void *buf, size_t len)
2096 {
2097 
2098 	if (sopt->sopt_size != len)
2099 		return EINVAL;
2100 
2101 	memcpy(buf, sopt->sopt_data, len);
2102 	return 0;
2103 }
2104 
2105 /*
2106  * common case of get sockopt integer value
2107  */
2108 int
2109 sockopt_getint(const struct sockopt *sopt, int *valp)
2110 {
2111 
2112 	return sockopt_get(sopt, valp, sizeof(int));
2113 }
2114 
2115 /*
2116  * set sockopt value from mbuf
2117  *	- ONLY for legacy code
2118  *	- mbuf is released by sockopt
2119  *	- will not sleep
2120  */
2121 int
2122 sockopt_setmbuf(struct sockopt *sopt, struct mbuf *m)
2123 {
2124 	size_t len;
2125 	int error;
2126 
2127 	len = m_length(m);
2128 
2129 	if (sopt->sopt_size == 0) {
2130 		error = sockopt_alloc(sopt, len, KM_NOSLEEP);
2131 		if (error)
2132 			return error;
2133 	}
2134 
2135 	KASSERT(sopt->sopt_size == len);
2136 	m_copydata(m, 0, len, sopt->sopt_data);
2137 	m_freem(m);
2138 
2139 	return 0;
2140 }
2141 
2142 /*
2143  * get sockopt value into mbuf
2144  *	- ONLY for legacy code
2145  *	- mbuf to be released by the caller
2146  *	- will not sleep
2147  */
2148 struct mbuf *
2149 sockopt_getmbuf(const struct sockopt *sopt)
2150 {
2151 	struct mbuf *m;
2152 
2153 	if (sopt->sopt_size > MCLBYTES)
2154 		return NULL;
2155 
2156 	m = m_get(M_DONTWAIT, MT_SOOPTS);
2157 	if (m == NULL)
2158 		return NULL;
2159 
2160 	if (sopt->sopt_size > MLEN) {
2161 		MCLGET(m, M_DONTWAIT);
2162 		if ((m->m_flags & M_EXT) == 0) {
2163 			m_free(m);
2164 			return NULL;
2165 		}
2166 	}
2167 
2168 	memcpy(mtod(m, void *), sopt->sopt_data, sopt->sopt_size);
2169 	m->m_len = sopt->sopt_size;
2170 
2171 	return m;
2172 }
2173 
2174 void
2175 sohasoutofband(struct socket *so)
2176 {
2177 
2178 	fownsignal(so->so_pgid, SIGURG, POLL_PRI, POLLPRI|POLLRDBAND, so);
2179 	selnotify(&so->so_rcv.sb_sel, POLLPRI | POLLRDBAND, NOTE_SUBMIT);
2180 }
2181 
2182 static void
2183 filt_sordetach(struct knote *kn)
2184 {
2185 	struct socket	*so;
2186 
2187 	so = ((file_t *)kn->kn_obj)->f_data;
2188 	solock(so);
2189 	SLIST_REMOVE(&so->so_rcv.sb_sel.sel_klist, kn, knote, kn_selnext);
2190 	if (SLIST_EMPTY(&so->so_rcv.sb_sel.sel_klist))
2191 		so->so_rcv.sb_flags &= ~SB_KNOTE;
2192 	sounlock(so);
2193 }
2194 
2195 /*ARGSUSED*/
2196 static int
2197 filt_soread(struct knote *kn, long hint)
2198 {
2199 	struct socket	*so;
2200 	int rv;
2201 
2202 	so = ((file_t *)kn->kn_obj)->f_data;
2203 	if (hint != NOTE_SUBMIT)
2204 		solock(so);
2205 	kn->kn_data = so->so_rcv.sb_cc;
2206 	if (so->so_state & SS_CANTRCVMORE) {
2207 		kn->kn_flags |= EV_EOF;
2208 		kn->kn_fflags = so->so_error;
2209 		rv = 1;
2210 	} else if (so->so_error)	/* temporary udp error */
2211 		rv = 1;
2212 	else if (kn->kn_sfflags & NOTE_LOWAT)
2213 		rv = (kn->kn_data >= kn->kn_sdata);
2214 	else
2215 		rv = (kn->kn_data >= so->so_rcv.sb_lowat);
2216 	if (hint != NOTE_SUBMIT)
2217 		sounlock(so);
2218 	return rv;
2219 }
2220 
2221 static void
2222 filt_sowdetach(struct knote *kn)
2223 {
2224 	struct socket	*so;
2225 
2226 	so = ((file_t *)kn->kn_obj)->f_data;
2227 	solock(so);
2228 	SLIST_REMOVE(&so->so_snd.sb_sel.sel_klist, kn, knote, kn_selnext);
2229 	if (SLIST_EMPTY(&so->so_snd.sb_sel.sel_klist))
2230 		so->so_snd.sb_flags &= ~SB_KNOTE;
2231 	sounlock(so);
2232 }
2233 
2234 /*ARGSUSED*/
2235 static int
2236 filt_sowrite(struct knote *kn, long hint)
2237 {
2238 	struct socket	*so;
2239 	int rv;
2240 
2241 	so = ((file_t *)kn->kn_obj)->f_data;
2242 	if (hint != NOTE_SUBMIT)
2243 		solock(so);
2244 	kn->kn_data = sbspace(&so->so_snd);
2245 	if (so->so_state & SS_CANTSENDMORE) {
2246 		kn->kn_flags |= EV_EOF;
2247 		kn->kn_fflags = so->so_error;
2248 		rv = 1;
2249 	} else if (so->so_error)	/* temporary udp error */
2250 		rv = 1;
2251 	else if (((so->so_state & SS_ISCONNECTED) == 0) &&
2252 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
2253 		rv = 0;
2254 	else if (kn->kn_sfflags & NOTE_LOWAT)
2255 		rv = (kn->kn_data >= kn->kn_sdata);
2256 	else
2257 		rv = (kn->kn_data >= so->so_snd.sb_lowat);
2258 	if (hint != NOTE_SUBMIT)
2259 		sounlock(so);
2260 	return rv;
2261 }
2262 
2263 /*ARGSUSED*/
2264 static int
2265 filt_solisten(struct knote *kn, long hint)
2266 {
2267 	struct socket	*so;
2268 	int rv;
2269 
2270 	so = ((file_t *)kn->kn_obj)->f_data;
2271 
2272 	/*
2273 	 * Set kn_data to number of incoming connections, not
2274 	 * counting partial (incomplete) connections.
2275 	 */
2276 	if (hint != NOTE_SUBMIT)
2277 		solock(so);
2278 	kn->kn_data = so->so_qlen;
2279 	rv = (kn->kn_data > 0);
2280 	if (hint != NOTE_SUBMIT)
2281 		sounlock(so);
2282 	return rv;
2283 }
2284 
2285 static const struct filterops solisten_filtops =
2286 	{ 1, NULL, filt_sordetach, filt_solisten };
2287 static const struct filterops soread_filtops =
2288 	{ 1, NULL, filt_sordetach, filt_soread };
2289 static const struct filterops sowrite_filtops =
2290 	{ 1, NULL, filt_sowdetach, filt_sowrite };
2291 
2292 int
2293 soo_kqfilter(struct file *fp, struct knote *kn)
2294 {
2295 	struct socket	*so;
2296 	struct sockbuf	*sb;
2297 
2298 	so = ((file_t *)kn->kn_obj)->f_data;
2299 	solock(so);
2300 	switch (kn->kn_filter) {
2301 	case EVFILT_READ:
2302 		if (so->so_options & SO_ACCEPTCONN)
2303 			kn->kn_fop = &solisten_filtops;
2304 		else
2305 			kn->kn_fop = &soread_filtops;
2306 		sb = &so->so_rcv;
2307 		break;
2308 	case EVFILT_WRITE:
2309 		kn->kn_fop = &sowrite_filtops;
2310 		sb = &so->so_snd;
2311 		break;
2312 	default:
2313 		sounlock(so);
2314 		return (EINVAL);
2315 	}
2316 	SLIST_INSERT_HEAD(&sb->sb_sel.sel_klist, kn, kn_selnext);
2317 	sb->sb_flags |= SB_KNOTE;
2318 	sounlock(so);
2319 	return (0);
2320 }
2321 
2322 static int
2323 sodopoll(struct socket *so, int events)
2324 {
2325 	int revents;
2326 
2327 	revents = 0;
2328 
2329 	if (events & (POLLIN | POLLRDNORM))
2330 		if (soreadable(so))
2331 			revents |= events & (POLLIN | POLLRDNORM);
2332 
2333 	if (events & (POLLOUT | POLLWRNORM))
2334 		if (sowritable(so))
2335 			revents |= events & (POLLOUT | POLLWRNORM);
2336 
2337 	if (events & (POLLPRI | POLLRDBAND))
2338 		if (so->so_oobmark || (so->so_state & SS_RCVATMARK))
2339 			revents |= events & (POLLPRI | POLLRDBAND);
2340 
2341 	return revents;
2342 }
2343 
2344 int
2345 sopoll(struct socket *so, int events)
2346 {
2347 	int revents = 0;
2348 
2349 #ifndef DIAGNOSTIC
2350 	/*
2351 	 * Do a quick, unlocked check in expectation that the socket
2352 	 * will be ready for I/O.  Don't do this check if DIAGNOSTIC,
2353 	 * as the solocked() assertions will fail.
2354 	 */
2355 	if ((revents = sodopoll(so, events)) != 0)
2356 		return revents;
2357 #endif
2358 
2359 	solock(so);
2360 	if ((revents = sodopoll(so, events)) == 0) {
2361 		if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
2362 			selrecord(curlwp, &so->so_rcv.sb_sel);
2363 			so->so_rcv.sb_flags |= SB_NOTIFY;
2364 		}
2365 
2366 		if (events & (POLLOUT | POLLWRNORM)) {
2367 			selrecord(curlwp, &so->so_snd.sb_sel);
2368 			so->so_snd.sb_flags |= SB_NOTIFY;
2369 		}
2370 	}
2371 	sounlock(so);
2372 
2373 	return revents;
2374 }
2375 
2376 
2377 #include <sys/sysctl.h>
2378 
2379 static int sysctl_kern_somaxkva(SYSCTLFN_PROTO);
2380 
2381 /*
2382  * sysctl helper routine for kern.somaxkva.  ensures that the given
2383  * value is not too small.
2384  * (XXX should we maybe make sure it's not too large as well?)
2385  */
2386 static int
2387 sysctl_kern_somaxkva(SYSCTLFN_ARGS)
2388 {
2389 	int error, new_somaxkva;
2390 	struct sysctlnode node;
2391 
2392 	new_somaxkva = somaxkva;
2393 	node = *rnode;
2394 	node.sysctl_data = &new_somaxkva;
2395 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
2396 	if (error || newp == NULL)
2397 		return (error);
2398 
2399 	if (new_somaxkva < (16 * 1024 * 1024)) /* sanity */
2400 		return (EINVAL);
2401 
2402 	mutex_enter(&so_pendfree_lock);
2403 	somaxkva = new_somaxkva;
2404 	cv_broadcast(&socurkva_cv);
2405 	mutex_exit(&so_pendfree_lock);
2406 
2407 	return (error);
2408 }
2409 
2410 static void
2411 sysctl_kern_somaxkva_setup(void)
2412 {
2413 
2414 	KASSERT(socket_sysctllog == NULL);
2415 	sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
2416 		       CTLFLAG_PERMANENT,
2417 		       CTLTYPE_NODE, "kern", NULL,
2418 		       NULL, 0, NULL, 0,
2419 		       CTL_KERN, CTL_EOL);
2420 
2421 	sysctl_createv(&socket_sysctllog, 0, NULL, NULL,
2422 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2423 		       CTLTYPE_INT, "somaxkva",
2424 		       SYSCTL_DESCR("Maximum amount of kernel memory to be "
2425 				    "used for socket buffers"),
2426 		       sysctl_kern_somaxkva, 0, NULL, 0,
2427 		       CTL_KERN, KERN_SOMAXKVA, CTL_EOL);
2428 }
2429