xref: /dragonfly/sys/kern/uipc_syscalls.c (revision 927da715)
1 /*
2  * Copyright (c) 1982, 1986, 1989, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * sendfile(2) and related extensions:
6  * Copyright (c) 1998, David Greenman. All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)uipc_syscalls.c	8.4 (Berkeley) 2/21/94
37  * $FreeBSD: src/sys/kern/uipc_syscalls.c,v 1.65.2.17 2003/04/04 17:11:16 tegge Exp $
38  * $DragonFly: src/sys/kern/uipc_syscalls.c,v 1.89 2008/07/26 15:36:28 sephe Exp $
39  */
40 
41 #include "opt_ktrace.h"
42 #include "opt_sctp.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/sysproto.h>
48 #include <sys/malloc.h>
49 #include <sys/filedesc.h>
50 #include <sys/event.h>
51 #include <sys/proc.h>
52 #include <sys/fcntl.h>
53 #include <sys/file.h>
54 #include <sys/filio.h>
55 #include <sys/kern_syscall.h>
56 #include <sys/mbuf.h>
57 #include <sys/protosw.h>
58 #include <sys/sfbuf.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/socketops.h>
62 #include <sys/uio.h>
63 #include <sys/vnode.h>
64 #include <sys/lock.h>
65 #include <sys/mount.h>
66 #ifdef KTRACE
67 #include <sys/ktrace.h>
68 #endif
69 #include <vm/vm.h>
70 #include <vm/vm_object.h>
71 #include <vm/vm_page.h>
72 #include <vm/vm_pageout.h>
73 #include <vm/vm_kern.h>
74 #include <vm/vm_extern.h>
75 #include <sys/file2.h>
76 #include <sys/signalvar.h>
77 #include <sys/serialize.h>
78 
79 #include <sys/thread2.h>
80 #include <sys/msgport2.h>
81 #include <sys/socketvar2.h>
82 #include <net/netmsg2.h>
83 
84 #ifdef SCTP
85 #include <netinet/sctp_peeloff.h>
86 #endif /* SCTP */
87 
88 struct sfbuf_mref {
89 	struct sf_buf	*sf;
90 	int		mref_count;
91 	struct lwkt_serialize serializer;
92 };
93 
94 static MALLOC_DEFINE(M_SENDFILE, "sendfile", "sendfile sfbuf ref structures");
95 
96 /*
97  * System call interface to the socket abstraction.
98  */
99 
100 extern	struct fileops socketops;
101 
102 /*
103  * socket_args(int domain, int type, int protocol)
104  */
105 int
106 kern_socket(int domain, int type, int protocol, int *res)
107 {
108 	struct thread *td = curthread;
109 	struct proc *p = td->td_proc;
110 	struct socket *so;
111 	struct file *fp;
112 	int fd, error;
113 
114 	KKASSERT(p);
115 
116 	error = falloc(p, &fp, &fd);
117 	if (error)
118 		return (error);
119 	error = socreate(domain, &so, type, protocol, td);
120 	if (error) {
121 		fsetfd(p, NULL, fd);
122 	} else {
123 		fp->f_type = DTYPE_SOCKET;
124 		fp->f_flag = FREAD | FWRITE;
125 		fp->f_ops = &socketops;
126 		fp->f_data = so;
127 		*res = fd;
128 		fsetfd(p, fp, fd);
129 	}
130 	fdrop(fp);
131 	return (error);
132 }
133 
134 int
135 sys_socket(struct socket_args *uap)
136 {
137 	int error;
138 
139 	error = kern_socket(uap->domain, uap->type, uap->protocol,
140 	    &uap->sysmsg_result);
141 
142 	return (error);
143 }
144 
145 int
146 kern_bind(int s, struct sockaddr *sa)
147 {
148 	struct thread *td = curthread;
149 	struct proc *p = td->td_proc;
150 	struct file *fp;
151 	int error;
152 
153 	KKASSERT(p);
154 	error = holdsock(p->p_fd, s, &fp);
155 	if (error)
156 		return (error);
157 	error = sobind((struct socket *)fp->f_data, sa, td);
158 	fdrop(fp);
159 	return (error);
160 }
161 
162 /*
163  * bind_args(int s, caddr_t name, int namelen)
164  */
165 int
166 sys_bind(struct bind_args *uap)
167 {
168 	struct sockaddr *sa;
169 	int error;
170 
171 	error = getsockaddr(&sa, uap->name, uap->namelen);
172 	if (error)
173 		return (error);
174 	error = kern_bind(uap->s, sa);
175 	FREE(sa, M_SONAME);
176 
177 	return (error);
178 }
179 
180 int
181 kern_listen(int s, int backlog)
182 {
183 	struct thread *td = curthread;
184 	struct proc *p = td->td_proc;
185 	struct file *fp;
186 	int error;
187 
188 	KKASSERT(p);
189 	error = holdsock(p->p_fd, s, &fp);
190 	if (error)
191 		return (error);
192 	error = solisten((struct socket *)fp->f_data, backlog, td);
193 	fdrop(fp);
194 	return(error);
195 }
196 
197 /*
198  * listen_args(int s, int backlog)
199  */
200 int
201 sys_listen(struct listen_args *uap)
202 {
203 	int error;
204 
205 	error = kern_listen(uap->s, uap->backlog);
206 	return (error);
207 }
208 
209 /*
210  * Returns the accepted socket as well.
211  */
212 static boolean_t
213 soaccept_predicate(struct netmsg *msg0)
214 {
215 	struct netmsg_so_notify *msg = (struct netmsg_so_notify *)msg0;
216 	struct socket *head = msg->nm_so;
217 
218 	if (head->so_error != 0) {
219 		msg->nm_netmsg.nm_lmsg.ms_error = head->so_error;
220 		return (TRUE);
221 	}
222 	if (!TAILQ_EMPTY(&head->so_comp)) {
223 		/* Abuse nm_so field as copy in/copy out parameter. XXX JH */
224 		msg->nm_so = TAILQ_FIRST(&head->so_comp);
225 		TAILQ_REMOVE(&head->so_comp, msg->nm_so, so_list);
226 		head->so_qlen--;
227 
228 		msg->nm_netmsg.nm_lmsg.ms_error = 0;
229 		return (TRUE);
230 	}
231 	if (head->so_state & SS_CANTRCVMORE) {
232 		msg->nm_netmsg.nm_lmsg.ms_error = ECONNABORTED;
233 		return (TRUE);
234 	}
235 	if (msg->nm_fflags & FNONBLOCK) {
236 		msg->nm_netmsg.nm_lmsg.ms_error = EWOULDBLOCK;
237 		return (TRUE);
238 	}
239 
240 	return (FALSE);
241 }
242 
243 /*
244  * The second argument to kern_accept() is a handle to a struct sockaddr.
245  * This allows kern_accept() to return a pointer to an allocated struct
246  * sockaddr which must be freed later with FREE().  The caller must
247  * initialize *name to NULL.
248  */
249 int
250 kern_accept(int s, int fflags, struct sockaddr **name, int *namelen, int *res)
251 {
252 	struct thread *td = curthread;
253 	struct proc *p = td->td_proc;
254 	struct file *lfp = NULL;
255 	struct file *nfp = NULL;
256 	struct sockaddr *sa;
257 	struct socket *head, *so;
258 	struct netmsg_so_notify msg;
259 	lwkt_port_t port;
260 	int fd;
261 	u_int fflag;		/* type must match fp->f_flag */
262 	int error, tmp;
263 
264 	*res = -1;
265 	if (name && namelen && *namelen < 0)
266 		return (EINVAL);
267 
268 	error = holdsock(p->p_fd, s, &lfp);
269 	if (error)
270 		return (error);
271 
272 	error = falloc(p, &nfp, &fd);
273 	if (error) {		/* Probably ran out of file descriptors. */
274 		fdrop(lfp);
275 		return (error);
276 	}
277 	head = (struct socket *)lfp->f_data;
278 	if ((head->so_options & SO_ACCEPTCONN) == 0) {
279 		error = EINVAL;
280 		goto done;
281 	}
282 
283 	if (fflags & O_FBLOCKING)
284 		fflags |= lfp->f_flag & ~FNONBLOCK;
285 	else if (fflags & O_FNONBLOCKING)
286 		fflags |= lfp->f_flag | FNONBLOCK;
287 	else
288 		fflags = lfp->f_flag;
289 
290 	/* optimize for uniprocessor case later XXX JH */
291 	port = head->so_proto->pr_mport(head, NULL, NULL, PRU_PRED);
292 	netmsg_init_abortable(&msg.nm_netmsg, &curthread->td_msgport,
293 			      0,
294 			      netmsg_so_notify,
295 			      netmsg_so_notify_doabort);
296 	msg.nm_predicate = soaccept_predicate;
297 	msg.nm_fflags = fflags;
298 	msg.nm_so = head;
299 	msg.nm_etype = NM_REVENT;
300 	error = lwkt_domsg(port, &msg.nm_netmsg.nm_lmsg, PCATCH);
301 	if (error)
302 		goto done;
303 
304 	/*
305 	 * At this point we have the connection that's ready to be accepted.
306 	 */
307 	so = msg.nm_so;
308 
309 	fflag = lfp->f_flag;
310 
311 	/* connection has been removed from the listen queue */
312 	KNOTE(&head->so_rcv.ssb_sel.si_note, 0);
313 
314 	so->so_state &= ~SS_COMP;
315 	so->so_head = NULL;
316 	if (head->so_sigio != NULL)
317 		fsetown(fgetown(head->so_sigio), &so->so_sigio);
318 
319 	nfp->f_type = DTYPE_SOCKET;
320 	nfp->f_flag = fflag;
321 	nfp->f_ops = &socketops;
322 	nfp->f_data = so;
323 	/* Sync socket nonblocking/async state with file flags */
324 	tmp = fflag & FNONBLOCK;
325 	(void) fo_ioctl(nfp, FIONBIO, (caddr_t)&tmp, p->p_ucred);
326 	tmp = fflag & FASYNC;
327 	(void) fo_ioctl(nfp, FIOASYNC, (caddr_t)&tmp, p->p_ucred);
328 
329 	sa = NULL;
330 	error = soaccept(so, &sa);
331 
332 	/*
333 	 * Set the returned name and namelen as applicable.  Set the returned
334 	 * namelen to 0 for older code which might ignore the return value
335 	 * from accept.
336 	 */
337 	if (error == 0) {
338 		if (sa && name && namelen) {
339 			if (*namelen > sa->sa_len)
340 				*namelen = sa->sa_len;
341 			*name = sa;
342 		} else {
343 			if (sa)
344 				FREE(sa, M_SONAME);
345 		}
346 	}
347 
348 done:
349 	/*
350 	 * If an error occured clear the reserved descriptor, else associate
351 	 * nfp with it.
352 	 *
353 	 * Note that *res is normally ignored if an error is returned but
354 	 * a syscall message will still have access to the result code.
355 	 */
356 	if (error) {
357 		fsetfd(p, NULL, fd);
358 	} else {
359 		*res = fd;
360 		fsetfd(p, nfp, fd);
361 	}
362 	fdrop(nfp);
363 	fdrop(lfp);
364 	return (error);
365 }
366 
367 /*
368  * accept(int s, caddr_t name, int *anamelen)
369  */
370 int
371 sys_accept(struct accept_args *uap)
372 {
373 	struct sockaddr *sa = NULL;
374 	int sa_len;
375 	int error;
376 
377 	if (uap->name) {
378 		error = copyin(uap->anamelen, &sa_len, sizeof(sa_len));
379 		if (error)
380 			return (error);
381 
382 		error = kern_accept(uap->s, 0, &sa, &sa_len, &uap->sysmsg_result);
383 
384 		if (error == 0)
385 			error = copyout(sa, uap->name, sa_len);
386 		if (error == 0) {
387 			error = copyout(&sa_len, uap->anamelen,
388 			    sizeof(*uap->anamelen));
389 		}
390 		if (sa)
391 			FREE(sa, M_SONAME);
392 	} else {
393 		error = kern_accept(uap->s, 0, NULL, 0, &uap->sysmsg_result);
394 	}
395 	return (error);
396 }
397 
398 /*
399  * extaccept(int s, int fflags, caddr_t name, int *anamelen)
400  */
401 int
402 sys_extaccept(struct extaccept_args *uap)
403 {
404 	struct sockaddr *sa = NULL;
405 	int sa_len;
406 	int error;
407 	int fflags = uap->flags & O_FMASK;
408 
409 	if (uap->name) {
410 		error = copyin(uap->anamelen, &sa_len, sizeof(sa_len));
411 		if (error)
412 			return (error);
413 
414 		error = kern_accept(uap->s, fflags, &sa, &sa_len, &uap->sysmsg_result);
415 
416 		if (error == 0)
417 			error = copyout(sa, uap->name, sa_len);
418 		if (error == 0) {
419 			error = copyout(&sa_len, uap->anamelen,
420 			    sizeof(*uap->anamelen));
421 		}
422 		if (sa)
423 			FREE(sa, M_SONAME);
424 	} else {
425 		error = kern_accept(uap->s, fflags, NULL, 0, &uap->sysmsg_result);
426 	}
427 	return (error);
428 }
429 
430 
431 /*
432  * Returns TRUE if predicate satisfied.
433  */
434 static boolean_t
435 soconnected_predicate(struct netmsg *msg0)
436 {
437 	struct netmsg_so_notify *msg = (struct netmsg_so_notify *)msg0;
438 	struct socket *so = msg->nm_so;
439 
440 	/* check predicate */
441 	if (!(so->so_state & SS_ISCONNECTING) || so->so_error != 0) {
442 		msg->nm_netmsg.nm_lmsg.ms_error = so->so_error;
443 		return (TRUE);
444 	}
445 
446 	return (FALSE);
447 }
448 
449 int
450 kern_connect(int s, int fflags, struct sockaddr *sa)
451 {
452 	struct thread *td = curthread;
453 	struct proc *p = td->td_proc;
454 	struct file *fp;
455 	struct socket *so;
456 	int error, interrupted = 0;
457 
458 	error = holdsock(p->p_fd, s, &fp);
459 	if (error)
460 		return (error);
461 	so = (struct socket *)fp->f_data;
462 
463 	if (fflags & O_FBLOCKING)
464 		/* fflags &= ~FNONBLOCK; */;
465 	else if (fflags & O_FNONBLOCKING)
466 		fflags |= FNONBLOCK;
467 	else
468 		fflags = fp->f_flag;
469 
470 	if (so->so_state & SS_ISCONNECTING) {
471 		error = EALREADY;
472 		goto done;
473 	}
474 	error = soconnect(so, sa, td);
475 	if (error)
476 		goto bad;
477 	if ((fflags & FNONBLOCK) && (so->so_state & SS_ISCONNECTING)) {
478 		error = EINPROGRESS;
479 		goto done;
480 	}
481 	if ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
482 		struct netmsg_so_notify msg;
483 		lwkt_port_t port;
484 
485 		port = so->so_proto->pr_mport(so, sa, NULL, PRU_PRED);
486 		netmsg_init_abortable(&msg.nm_netmsg,
487 				      &curthread->td_msgport,
488 				      0,
489 				      netmsg_so_notify,
490 				      netmsg_so_notify_doabort);
491 		msg.nm_predicate = soconnected_predicate;
492 		msg.nm_so = so;
493 		msg.nm_etype = NM_REVENT;
494 		error = lwkt_domsg(port, &msg.nm_netmsg.nm_lmsg, PCATCH);
495 		if (error == EINTR || error == ERESTART)
496 			interrupted = 1;
497 	}
498 	if (error == 0) {
499 		error = so->so_error;
500 		so->so_error = 0;
501 	}
502 bad:
503 	if (!interrupted)
504 		so->so_state &= ~SS_ISCONNECTING;
505 	if (error == ERESTART)
506 		error = EINTR;
507 done:
508 	fdrop(fp);
509 	return (error);
510 }
511 
512 /*
513  * connect_args(int s, caddr_t name, int namelen)
514  */
515 int
516 sys_connect(struct connect_args *uap)
517 {
518 	struct sockaddr *sa;
519 	int error;
520 
521 	error = getsockaddr(&sa, uap->name, uap->namelen);
522 	if (error)
523 		return (error);
524 	error = kern_connect(uap->s, 0, sa);
525 	FREE(sa, M_SONAME);
526 
527 	return (error);
528 }
529 
530 /*
531  * connect_args(int s, int fflags, caddr_t name, int namelen)
532  */
533 int
534 sys_extconnect(struct extconnect_args *uap)
535 {
536 	struct sockaddr *sa;
537 	int error;
538 	int fflags = uap->flags & O_FMASK;
539 
540 	error = getsockaddr(&sa, uap->name, uap->namelen);
541 	if (error)
542 		return (error);
543 	error = kern_connect(uap->s, fflags, sa);
544 	FREE(sa, M_SONAME);
545 
546 	return (error);
547 }
548 
549 int
550 kern_socketpair(int domain, int type, int protocol, int *sv)
551 {
552 	struct thread *td = curthread;
553 	struct proc *p = td->td_proc;
554 	struct file *fp1, *fp2;
555 	struct socket *so1, *so2;
556 	int fd1, fd2, error;
557 
558 	KKASSERT(p);
559 	error = socreate(domain, &so1, type, protocol, td);
560 	if (error)
561 		return (error);
562 	error = socreate(domain, &so2, type, protocol, td);
563 	if (error)
564 		goto free1;
565 	error = falloc(p, &fp1, &fd1);
566 	if (error)
567 		goto free2;
568 	sv[0] = fd1;
569 	fp1->f_data = so1;
570 	error = falloc(p, &fp2, &fd2);
571 	if (error)
572 		goto free3;
573 	fp2->f_data = so2;
574 	sv[1] = fd2;
575 	error = soconnect2(so1, so2);
576 	if (error)
577 		goto free4;
578 	if (type == SOCK_DGRAM) {
579 		/*
580 		 * Datagram socket connection is asymmetric.
581 		 */
582 		 error = soconnect2(so2, so1);
583 		 if (error)
584 			goto free4;
585 	}
586 	fp1->f_type = fp2->f_type = DTYPE_SOCKET;
587 	fp1->f_flag = fp2->f_flag = FREAD|FWRITE;
588 	fp1->f_ops = fp2->f_ops = &socketops;
589 	fsetfd(p, fp1, fd1);
590 	fsetfd(p, fp2, fd2);
591 	fdrop(fp1);
592 	fdrop(fp2);
593 	return (error);
594 free4:
595 	fsetfd(p, NULL, fd2);
596 	fdrop(fp2);
597 free3:
598 	fsetfd(p, NULL, fd1);
599 	fdrop(fp1);
600 free2:
601 	(void)soclose(so2, 0);
602 free1:
603 	(void)soclose(so1, 0);
604 	return (error);
605 }
606 
607 /*
608  * socketpair(int domain, int type, int protocol, int *rsv)
609  */
610 int
611 sys_socketpair(struct socketpair_args *uap)
612 {
613 	int error, sockv[2];
614 
615 	error = kern_socketpair(uap->domain, uap->type, uap->protocol, sockv);
616 
617 	if (error == 0)
618 		error = copyout(sockv, uap->rsv, sizeof(sockv));
619 	return (error);
620 }
621 
622 int
623 kern_sendmsg(int s, struct sockaddr *sa, struct uio *auio,
624     struct mbuf *control, int flags, int *res)
625 {
626 	struct thread *td = curthread;
627 	struct lwp *lp = td->td_lwp;
628 	struct proc *p = td->td_proc;
629 	struct file *fp;
630 	int len, error;
631 	struct socket *so;
632 #ifdef KTRACE
633 	struct iovec *ktriov = NULL;
634 	struct uio ktruio;
635 #endif
636 
637 	error = holdsock(p->p_fd, s, &fp);
638 	if (error)
639 		return (error);
640 	if (auio->uio_resid < 0) {
641 		error = EINVAL;
642 		goto done;
643 	}
644 #ifdef KTRACE
645 	if (KTRPOINT(td, KTR_GENIO)) {
646 		int iovlen = auio->uio_iovcnt * sizeof (struct iovec);
647 
648 		MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
649 		bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen);
650 		ktruio = *auio;
651 	}
652 #endif
653 	len = auio->uio_resid;
654 	so = (struct socket *)fp->f_data;
655 	if ((flags & (MSG_FNONBLOCKING|MSG_FBLOCKING)) == 0) {
656 		if (fp->f_flag & FNONBLOCK)
657 			flags |= MSG_FNONBLOCKING;
658 	}
659 	error = so_pru_sosend(so, sa, auio, NULL, control, flags, td);
660 	if (error) {
661 		if (auio->uio_resid != len && (error == ERESTART ||
662 		    error == EINTR || error == EWOULDBLOCK))
663 			error = 0;
664 		if (error == EPIPE)
665 			lwpsignal(p, lp, SIGPIPE);
666 	}
667 #ifdef KTRACE
668 	if (ktriov != NULL) {
669 		if (error == 0) {
670 			ktruio.uio_iov = ktriov;
671 			ktruio.uio_resid = len - auio->uio_resid;
672 			ktrgenio(lp, s, UIO_WRITE, &ktruio, error);
673 		}
674 		FREE(ktriov, M_TEMP);
675 	}
676 #endif
677 	if (error == 0)
678 		*res  = len - auio->uio_resid;
679 done:
680 	fdrop(fp);
681 	return (error);
682 }
683 
684 /*
685  * sendto_args(int s, caddr_t buf, size_t len, int flags, caddr_t to, int tolen)
686  */
687 int
688 sys_sendto(struct sendto_args *uap)
689 {
690 	struct thread *td = curthread;
691 	struct uio auio;
692 	struct iovec aiov;
693 	struct sockaddr *sa = NULL;
694 	int error;
695 
696 	if (uap->to) {
697 		error = getsockaddr(&sa, uap->to, uap->tolen);
698 		if (error)
699 			return (error);
700 	}
701 	aiov.iov_base = uap->buf;
702 	aiov.iov_len = uap->len;
703 	auio.uio_iov = &aiov;
704 	auio.uio_iovcnt = 1;
705 	auio.uio_offset = 0;
706 	auio.uio_resid = uap->len;
707 	auio.uio_segflg = UIO_USERSPACE;
708 	auio.uio_rw = UIO_WRITE;
709 	auio.uio_td = td;
710 
711 	error = kern_sendmsg(uap->s, sa, &auio, NULL, uap->flags,
712 	    &uap->sysmsg_result);
713 
714 	if (sa)
715 		FREE(sa, M_SONAME);
716 	return (error);
717 }
718 
719 /*
720  * sendmsg_args(int s, caddr_t msg, int flags)
721  */
722 int
723 sys_sendmsg(struct sendmsg_args *uap)
724 {
725 	struct thread *td = curthread;
726 	struct msghdr msg;
727 	struct uio auio;
728 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
729 	struct sockaddr *sa = NULL;
730 	struct mbuf *control = NULL;
731 	int error;
732 
733 	error = copyin(uap->msg, (caddr_t)&msg, sizeof(msg));
734 	if (error)
735 		return (error);
736 
737 	/*
738 	 * Conditionally copyin msg.msg_name.
739 	 */
740 	if (msg.msg_name) {
741 		error = getsockaddr(&sa, msg.msg_name, msg.msg_namelen);
742 		if (error)
743 			return (error);
744 	}
745 
746 	/*
747 	 * Populate auio.
748 	 */
749 	error = iovec_copyin(msg.msg_iov, &iov, aiov, msg.msg_iovlen,
750 			     &auio.uio_resid);
751 	if (error)
752 		goto cleanup2;
753 	auio.uio_iov = iov;
754 	auio.uio_iovcnt = msg.msg_iovlen;
755 	auio.uio_offset = 0;
756 	auio.uio_segflg = UIO_USERSPACE;
757 	auio.uio_rw = UIO_WRITE;
758 	auio.uio_td = td;
759 
760 	/*
761 	 * Conditionally copyin msg.msg_control.
762 	 */
763 	if (msg.msg_control) {
764 		if (msg.msg_controllen < sizeof(struct cmsghdr) ||
765 		    msg.msg_controllen > MLEN) {
766 			error = EINVAL;
767 			goto cleanup;
768 		}
769 		control = m_get(MB_WAIT, MT_CONTROL);
770 		if (control == NULL) {
771 			error = ENOBUFS;
772 			goto cleanup;
773 		}
774 		control->m_len = msg.msg_controllen;
775 		error = copyin(msg.msg_control, mtod(control, caddr_t),
776 		    msg.msg_controllen);
777 		if (error) {
778 			m_free(control);
779 			goto cleanup;
780 		}
781 	}
782 
783 	error = kern_sendmsg(uap->s, sa, &auio, control, uap->flags,
784 	    &uap->sysmsg_result);
785 
786 cleanup:
787 	iovec_free(&iov, aiov);
788 cleanup2:
789 	if (sa)
790 		FREE(sa, M_SONAME);
791 	return (error);
792 }
793 
794 /*
795  * kern_recvmsg() takes a handle to sa and control.  If the handle is non-
796  * null, it returns a dynamically allocated struct sockaddr and an mbuf.
797  * Don't forget to FREE() and m_free() these if they are returned.
798  */
799 int
800 kern_recvmsg(int s, struct sockaddr **sa, struct uio *auio,
801     struct mbuf **control, int *flags, int *res)
802 {
803 	struct thread *td = curthread;
804 	struct proc *p = td->td_proc;
805 	struct file *fp;
806 	int len, error;
807 	int lflags;
808 	struct socket *so;
809 #ifdef KTRACE
810 	struct iovec *ktriov = NULL;
811 	struct uio ktruio;
812 #endif
813 
814 	error = holdsock(p->p_fd, s, &fp);
815 	if (error)
816 		return (error);
817 	if (auio->uio_resid < 0) {
818 		error = EINVAL;
819 		goto done;
820 	}
821 #ifdef KTRACE
822 	if (KTRPOINT(td, KTR_GENIO)) {
823 		int iovlen = auio->uio_iovcnt * sizeof (struct iovec);
824 
825 		MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
826 		bcopy(auio->uio_iov, ktriov, iovlen);
827 		ktruio = *auio;
828 	}
829 #endif
830 	len = auio->uio_resid;
831 	so = (struct socket *)fp->f_data;
832 
833 	if (flags == NULL || (*flags & (MSG_FNONBLOCKING|MSG_FBLOCKING)) == 0) {
834 		if (fp->f_flag & FNONBLOCK) {
835 			if (flags) {
836 				*flags |= MSG_FNONBLOCKING;
837 			} else {
838 				lflags = MSG_FNONBLOCKING;
839 				flags = &lflags;
840 			}
841 		}
842 	}
843 
844 	error = so_pru_soreceive(so, sa, auio, NULL, control, flags);
845 	if (error) {
846 		if (auio->uio_resid != len && (error == ERESTART ||
847 		    error == EINTR || error == EWOULDBLOCK))
848 			error = 0;
849 	}
850 #ifdef KTRACE
851 	if (ktriov != NULL) {
852 		if (error == 0) {
853 			ktruio.uio_iov = ktriov;
854 			ktruio.uio_resid = len - auio->uio_resid;
855 			ktrgenio(td->td_lwp, s, UIO_READ, &ktruio, error);
856 		}
857 		FREE(ktriov, M_TEMP);
858 	}
859 #endif
860 	if (error == 0)
861 		*res = len - auio->uio_resid;
862 done:
863 	fdrop(fp);
864 	return (error);
865 }
866 
867 /*
868  * recvfrom_args(int s, caddr_t buf, size_t len, int flags,
869  *			caddr_t from, int *fromlenaddr)
870  */
871 int
872 sys_recvfrom(struct recvfrom_args *uap)
873 {
874 	struct thread *td = curthread;
875 	struct uio auio;
876 	struct iovec aiov;
877 	struct sockaddr *sa = NULL;
878 	int error, fromlen;
879 
880 	if (uap->from && uap->fromlenaddr) {
881 		error = copyin(uap->fromlenaddr, &fromlen, sizeof(fromlen));
882 		if (error)
883 			return (error);
884 		if (fromlen < 0)
885 			return (EINVAL);
886 	} else {
887 		fromlen = 0;
888 	}
889 	aiov.iov_base = uap->buf;
890 	aiov.iov_len = uap->len;
891 	auio.uio_iov = &aiov;
892 	auio.uio_iovcnt = 1;
893 	auio.uio_offset = 0;
894 	auio.uio_resid = uap->len;
895 	auio.uio_segflg = UIO_USERSPACE;
896 	auio.uio_rw = UIO_READ;
897 	auio.uio_td = td;
898 
899 	error = kern_recvmsg(uap->s, uap->from ? &sa : NULL, &auio, NULL,
900 	    &uap->flags, &uap->sysmsg_result);
901 
902 	if (error == 0 && uap->from) {
903 		/* note: sa may still be NULL */
904 		if (sa) {
905 			fromlen = MIN(fromlen, sa->sa_len);
906 			error = copyout(sa, uap->from, fromlen);
907 		} else {
908 			fromlen = 0;
909 		}
910 		if (error == 0) {
911 			error = copyout(&fromlen, uap->fromlenaddr,
912 					sizeof(fromlen));
913 		}
914 	}
915 	if (sa)
916 		FREE(sa, M_SONAME);
917 
918 	return (error);
919 }
920 
921 /*
922  * recvmsg_args(int s, struct msghdr *msg, int flags)
923  */
924 int
925 sys_recvmsg(struct recvmsg_args *uap)
926 {
927 	struct thread *td = curthread;
928 	struct msghdr msg;
929 	struct uio auio;
930 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
931 	struct mbuf *m, *control = NULL;
932 	struct sockaddr *sa = NULL;
933 	caddr_t ctlbuf;
934 	socklen_t *ufromlenp, *ucontrollenp;
935 	int error, fromlen, controllen, len, flags, *uflagsp;
936 
937 	/*
938 	 * This copyin handles everything except the iovec.
939 	 */
940 	error = copyin(uap->msg, &msg, sizeof(msg));
941 	if (error)
942 		return (error);
943 
944 	if (msg.msg_name && msg.msg_namelen < 0)
945 		return (EINVAL);
946 	if (msg.msg_control && msg.msg_controllen < 0)
947 		return (EINVAL);
948 
949 	ufromlenp = (socklen_t *)((caddr_t)uap->msg + offsetof(struct msghdr,
950 	    msg_namelen));
951 	ucontrollenp = (socklen_t *)((caddr_t)uap->msg + offsetof(struct msghdr,
952 	    msg_controllen));
953 	uflagsp = (int *)((caddr_t)uap->msg + offsetof(struct msghdr,
954 	    msg_flags));
955 
956 	/*
957 	 * Populate auio.
958 	 */
959 	error = iovec_copyin(msg.msg_iov, &iov, aiov, msg.msg_iovlen,
960 			     &auio.uio_resid);
961 	if (error)
962 		return (error);
963 	auio.uio_iov = iov;
964 	auio.uio_iovcnt = msg.msg_iovlen;
965 	auio.uio_offset = 0;
966 	auio.uio_segflg = UIO_USERSPACE;
967 	auio.uio_rw = UIO_READ;
968 	auio.uio_td = td;
969 
970 	flags = uap->flags;
971 
972 	error = kern_recvmsg(uap->s, msg.msg_name ? &sa : NULL, &auio,
973 	    msg.msg_control ? &control : NULL, &flags, &uap->sysmsg_result);
974 
975 	/*
976 	 * Conditionally copyout the name and populate the namelen field.
977 	 */
978 	if (error == 0 && msg.msg_name) {
979 		/* note: sa may still be NULL */
980 		if (sa != NULL) {
981 			fromlen = MIN(msg.msg_namelen, sa->sa_len);
982 			error = copyout(sa, msg.msg_name, fromlen);
983 		} else
984 			fromlen = 0;
985 		if (error == 0)
986 			error = copyout(&fromlen, ufromlenp,
987 			    sizeof(*ufromlenp));
988 	}
989 
990 	/*
991 	 * Copyout msg.msg_control and msg.msg_controllen.
992 	 */
993 	if (error == 0 && msg.msg_control) {
994 		len = msg.msg_controllen;
995 		m = control;
996 		ctlbuf = (caddr_t)msg.msg_control;
997 
998 		while(m && len > 0) {
999 			unsigned int tocopy;
1000 
1001 			if (len >= m->m_len) {
1002 				tocopy = m->m_len;
1003 			} else {
1004 				msg.msg_flags |= MSG_CTRUNC;
1005 				tocopy = len;
1006 			}
1007 
1008 			error = copyout(mtod(m, caddr_t), ctlbuf, tocopy);
1009 			if (error)
1010 				goto cleanup;
1011 
1012 			ctlbuf += tocopy;
1013 			len -= tocopy;
1014 			m = m->m_next;
1015 		}
1016 		controllen = ctlbuf - (caddr_t)msg.msg_control;
1017 		error = copyout(&controllen, ucontrollenp,
1018 		    sizeof(*ucontrollenp));
1019 	}
1020 
1021 	if (error == 0)
1022 		error = copyout(&flags, uflagsp, sizeof(*uflagsp));
1023 
1024 cleanup:
1025 	if (sa)
1026 		FREE(sa, M_SONAME);
1027 	iovec_free(&iov, aiov);
1028 	if (control)
1029 		m_freem(control);
1030 	return (error);
1031 }
1032 
1033 /*
1034  * If sopt->sopt_td == NULL, then sopt->sopt_val is treated as an
1035  * in kernel pointer instead of a userland pointer.  This allows us
1036  * to manipulate socket options in the emulation code.
1037  */
1038 int
1039 kern_setsockopt(int s, struct sockopt *sopt)
1040 {
1041 	struct thread *td = curthread;
1042 	struct proc *p = td->td_proc;
1043 	struct file *fp;
1044 	int error;
1045 
1046 	if (sopt->sopt_val == 0 && sopt->sopt_valsize != 0)
1047 		return (EFAULT);
1048 	if (sopt->sopt_valsize < 0)
1049 		return (EINVAL);
1050 
1051 	error = holdsock(p->p_fd, s, &fp);
1052 	if (error)
1053 		return (error);
1054 
1055 	error = sosetopt((struct socket *)fp->f_data, sopt);
1056 	fdrop(fp);
1057 	return (error);
1058 }
1059 
1060 /*
1061  * setsockopt_args(int s, int level, int name, caddr_t val, int valsize)
1062  */
1063 int
1064 sys_setsockopt(struct setsockopt_args *uap)
1065 {
1066 	struct thread *td = curthread;
1067 	struct sockopt sopt;
1068 	int error;
1069 
1070 	sopt.sopt_level = uap->level;
1071 	sopt.sopt_name = uap->name;
1072 	sopt.sopt_valsize = uap->valsize;
1073 	sopt.sopt_td = td;
1074 
1075 	if (uap->val) {
1076 		sopt.sopt_val = kmalloc(sopt.sopt_valsize, M_TEMP, M_WAITOK);
1077 		error = copyin(uap->val, sopt.sopt_val, sopt.sopt_valsize);
1078 		if (error)
1079 			goto out;
1080 	} else {
1081 		sopt.sopt_val = NULL;
1082 	}
1083 	error = kern_setsockopt(uap->s, &sopt);
1084 	if (error)
1085 		goto out;
1086 	if (uap->val)
1087 		error = copyout(sopt.sopt_val, uap->val, sopt.sopt_valsize);
1088 out:
1089 	if (uap->val)
1090 		kfree(sopt.sopt_val, M_TEMP);
1091 	return(error);
1092 }
1093 
1094 /*
1095  * If sopt->sopt_td == NULL, then sopt->sopt_val is treated as an
1096  * in kernel pointer instead of a userland pointer.  This allows us
1097  * to manipulate socket options in the emulation code.
1098  */
1099 int
1100 kern_getsockopt(int s, struct sockopt *sopt)
1101 {
1102 	struct thread *td = curthread;
1103 	struct proc *p = td->td_proc;
1104 	struct file *fp;
1105 	int error;
1106 
1107 	if (sopt->sopt_val == 0 && sopt->sopt_valsize != 0)
1108 		return (EFAULT);
1109 	if (sopt->sopt_valsize < 0)
1110 		return (EINVAL);
1111 
1112 	error = holdsock(p->p_fd, s, &fp);
1113 	if (error)
1114 		return (error);
1115 
1116 	error = sogetopt((struct socket *)fp->f_data, sopt);
1117 	fdrop(fp);
1118 	return (error);
1119 }
1120 
1121 /*
1122  * getsockopt_Args(int s, int level, int name, caddr_t val, int *avalsize)
1123  */
1124 int
1125 sys_getsockopt(struct getsockopt_args *uap)
1126 {
1127 	struct thread *td = curthread;
1128 	struct	sockopt sopt;
1129 	int	error, valsize;
1130 
1131 	if (uap->val) {
1132 		error = copyin(uap->avalsize, &valsize, sizeof(valsize));
1133 		if (error)
1134 			return (error);
1135 		if (valsize < 0)
1136 			return (EINVAL);
1137 	} else {
1138 		valsize = 0;
1139 	}
1140 
1141 	sopt.sopt_level = uap->level;
1142 	sopt.sopt_name = uap->name;
1143 	sopt.sopt_valsize = valsize;
1144 	sopt.sopt_td = td;
1145 
1146 	if (uap->val) {
1147 		sopt.sopt_val = kmalloc(sopt.sopt_valsize, M_TEMP, M_WAITOK);
1148 		error = copyin(uap->val, sopt.sopt_val, sopt.sopt_valsize);
1149 		if (error)
1150 			goto out;
1151 	} else {
1152 		sopt.sopt_val = NULL;
1153 	}
1154 	error = kern_getsockopt(uap->s, &sopt);
1155 	if (error)
1156 		goto out;
1157 	valsize = sopt.sopt_valsize;
1158 	error = copyout(&valsize, uap->avalsize, sizeof(valsize));
1159 	if (error)
1160 		goto out;
1161 	if (uap->val)
1162 		error = copyout(sopt.sopt_val, uap->val, sopt.sopt_valsize);
1163 out:
1164 	if (uap->val)
1165 		kfree(sopt.sopt_val, M_TEMP);
1166 	return (error);
1167 }
1168 
1169 /*
1170  * The second argument to kern_getsockname() is a handle to a struct sockaddr.
1171  * This allows kern_getsockname() to return a pointer to an allocated struct
1172  * sockaddr which must be freed later with FREE().  The caller must
1173  * initialize *name to NULL.
1174  */
1175 int
1176 kern_getsockname(int s, struct sockaddr **name, int *namelen)
1177 {
1178 	struct thread *td = curthread;
1179 	struct proc *p = td->td_proc;
1180 	struct file *fp;
1181 	struct socket *so;
1182 	struct sockaddr *sa = NULL;
1183 	int error;
1184 
1185 	error = holdsock(p->p_fd, s, &fp);
1186 	if (error)
1187 		return (error);
1188 	if (*namelen < 0) {
1189 		fdrop(fp);
1190 		return (EINVAL);
1191 	}
1192 	so = (struct socket *)fp->f_data;
1193 	error = so_pru_sockaddr(so, &sa);
1194 	if (error == 0) {
1195 		if (sa == 0) {
1196 			*namelen = 0;
1197 		} else {
1198 			*namelen = MIN(*namelen, sa->sa_len);
1199 			*name = sa;
1200 		}
1201 	}
1202 
1203 	fdrop(fp);
1204 	return (error);
1205 }
1206 
1207 /*
1208  * getsockname_args(int fdes, caddr_t asa, int *alen)
1209  *
1210  * Get socket name.
1211  */
1212 int
1213 sys_getsockname(struct getsockname_args *uap)
1214 {
1215 	struct sockaddr *sa = NULL;
1216 	int error, sa_len;
1217 
1218 	error = copyin(uap->alen, &sa_len, sizeof(sa_len));
1219 	if (error)
1220 		return (error);
1221 
1222 	error = kern_getsockname(uap->fdes, &sa, &sa_len);
1223 
1224 	if (error == 0)
1225 		error = copyout(sa, uap->asa, sa_len);
1226 	if (error == 0)
1227 		error = copyout(&sa_len, uap->alen, sizeof(*uap->alen));
1228 	if (sa)
1229 		FREE(sa, M_SONAME);
1230 	return (error);
1231 }
1232 
1233 /*
1234  * The second argument to kern_getpeername() is a handle to a struct sockaddr.
1235  * This allows kern_getpeername() to return a pointer to an allocated struct
1236  * sockaddr which must be freed later with FREE().  The caller must
1237  * initialize *name to NULL.
1238  */
1239 int
1240 kern_getpeername(int s, struct sockaddr **name, int *namelen)
1241 {
1242 	struct thread *td = curthread;
1243 	struct proc *p = td->td_proc;
1244 	struct file *fp;
1245 	struct socket *so;
1246 	struct sockaddr *sa = NULL;
1247 	int error;
1248 
1249 	error = holdsock(p->p_fd, s, &fp);
1250 	if (error)
1251 		return (error);
1252 	if (*namelen < 0) {
1253 		fdrop(fp);
1254 		return (EINVAL);
1255 	}
1256 	so = (struct socket *)fp->f_data;
1257 	if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
1258 		fdrop(fp);
1259 		return (ENOTCONN);
1260 	}
1261 	error = so_pru_peeraddr(so, &sa);
1262 	if (error == 0) {
1263 		if (sa == 0) {
1264 			*namelen = 0;
1265 		} else {
1266 			*namelen = MIN(*namelen, sa->sa_len);
1267 			*name = sa;
1268 		}
1269 	}
1270 
1271 	fdrop(fp);
1272 	return (error);
1273 }
1274 
1275 /*
1276  * getpeername_args(int fdes, caddr_t asa, int *alen)
1277  *
1278  * Get name of peer for connected socket.
1279  */
1280 int
1281 sys_getpeername(struct getpeername_args *uap)
1282 {
1283 	struct sockaddr *sa = NULL;
1284 	int error, sa_len;
1285 
1286 	error = copyin(uap->alen, &sa_len, sizeof(sa_len));
1287 	if (error)
1288 		return (error);
1289 
1290 	error = kern_getpeername(uap->fdes, &sa, &sa_len);
1291 
1292 	if (error == 0)
1293 		error = copyout(sa, uap->asa, sa_len);
1294 	if (error == 0)
1295 		error = copyout(&sa_len, uap->alen, sizeof(*uap->alen));
1296 	if (sa)
1297 		FREE(sa, M_SONAME);
1298 	return (error);
1299 }
1300 
1301 int
1302 getsockaddr(struct sockaddr **namp, caddr_t uaddr, size_t len)
1303 {
1304 	struct sockaddr *sa;
1305 	int error;
1306 
1307 	*namp = NULL;
1308 	if (len > SOCK_MAXADDRLEN)
1309 		return ENAMETOOLONG;
1310 	if (len < offsetof(struct sockaddr, sa_data[0]))
1311 		return EDOM;
1312 	MALLOC(sa, struct sockaddr *, len, M_SONAME, M_WAITOK);
1313 	error = copyin(uaddr, sa, len);
1314 	if (error) {
1315 		FREE(sa, M_SONAME);
1316 	} else {
1317 #if BYTE_ORDER != BIG_ENDIAN
1318 		/*
1319 		 * The bind(), connect(), and sendto() syscalls were not
1320 		 * versioned for COMPAT_43.  Thus, this check must stay.
1321 		 */
1322 		if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
1323 			sa->sa_family = sa->sa_len;
1324 #endif
1325 		sa->sa_len = len;
1326 		*namp = sa;
1327 	}
1328 	return error;
1329 }
1330 
1331 /*
1332  * Detach a mapped page and release resources back to the system.
1333  * We must release our wiring and if the object is ripped out
1334  * from under the vm_page we become responsible for freeing the
1335  * page.  These routines must be MPSAFE.
1336  *
1337  * XXX HACK XXX TEMPORARY UNTIL WE IMPLEMENT EXT MBUF REFERENCE COUNTING
1338  *
1339  * XXX vm_page_*() routines are not MPSAFE yet, the MP lock is required.
1340  */
1341 static void
1342 sf_buf_mref(void *arg)
1343 {
1344 	struct sfbuf_mref *sfm = arg;
1345 
1346 	/*
1347 	 * We must already hold a ref so there is no race to 0, just
1348 	 * atomically increment the count.
1349 	 */
1350 	atomic_add_int(&sfm->mref_count, 1);
1351 }
1352 
1353 static void
1354 sf_buf_mfree(void *arg)
1355 {
1356 	struct sfbuf_mref *sfm = arg;
1357 	vm_page_t m;
1358 
1359 	KKASSERT(sfm->mref_count > 0);
1360 	if (sfm->mref_count == 1) {
1361 		/*
1362 		 * We are the only holder so no further locking is required,
1363 		 * the sfbuf can simply be freed.
1364 		 */
1365 		sfm->mref_count = 0;
1366 		goto freeit;
1367 	} else {
1368 		/*
1369 		 * There may be other holders, we must obtain the serializer
1370 		 * to protect against a sf_buf_mfree() race to 0.  An atomic
1371 		 * operation is still required for races against
1372 		 * sf_buf_mref().
1373 		 *
1374 		 * XXX vm_page_*() and SFBUF routines not MPSAFE yet.
1375 		 */
1376 		lwkt_serialize_enter(&sfm->serializer);
1377 		atomic_subtract_int(&sfm->mref_count, 1);
1378 		if (sfm->mref_count == 0) {
1379 			lwkt_serialize_exit(&sfm->serializer);
1380 freeit:
1381 			get_mplock();
1382 			crit_enter();
1383 			m = sf_buf_page(sfm->sf);
1384 			sf_buf_free(sfm->sf);
1385 			vm_page_unwire(m, 0);
1386 			if (m->wire_count == 0 && m->object == NULL)
1387 				vm_page_try_to_free(m);
1388 			crit_exit();
1389 			rel_mplock();
1390 			kfree(sfm, M_SENDFILE);
1391 		} else {
1392 			lwkt_serialize_exit(&sfm->serializer);
1393 		}
1394 	}
1395 }
1396 
1397 /*
1398  * sendfile(2).
1399  * int sendfile(int fd, int s, off_t offset, size_t nbytes,
1400  *	 struct sf_hdtr *hdtr, off_t *sbytes, int flags)
1401  *
1402  * Send a file specified by 'fd' and starting at 'offset' to a socket
1403  * specified by 's'. Send only 'nbytes' of the file or until EOF if
1404  * nbytes == 0. Optionally add a header and/or trailer to the socket
1405  * output. If specified, write the total number of bytes sent into *sbytes.
1406  *
1407  * In FreeBSD kern/uipc_syscalls.c,v 1.103, a bug was fixed that caused
1408  * the headers to count against the remaining bytes to be sent from
1409  * the file descriptor.  We may wish to implement a compatibility syscall
1410  * in the future.
1411  */
1412 int
1413 sys_sendfile(struct sendfile_args *uap)
1414 {
1415 	struct thread *td = curthread;
1416 	struct proc *p = td->td_proc;
1417 	struct file *fp;
1418 	struct vnode *vp = NULL;
1419 	struct sf_hdtr hdtr;
1420 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
1421 	struct uio auio;
1422 	struct mbuf *mheader = NULL;
1423 	off_t hdtr_size = 0, sbytes;
1424 	int error, hbytes = 0, tbytes;
1425 
1426 	KKASSERT(p);
1427 
1428 	/*
1429 	 * Do argument checking. Must be a regular file in, stream
1430 	 * type and connected socket out, positive offset.
1431 	 */
1432 	fp = holdfp(p->p_fd, uap->fd, FREAD);
1433 	if (fp == NULL) {
1434 		return (EBADF);
1435 	}
1436 	if (fp->f_type != DTYPE_VNODE) {
1437 		fdrop(fp);
1438 		return (EINVAL);
1439 	}
1440 	vp = (struct vnode *)fp->f_data;
1441 	vref(vp);
1442 	fdrop(fp);
1443 
1444 	/*
1445 	 * If specified, get the pointer to the sf_hdtr struct for
1446 	 * any headers/trailers.
1447 	 */
1448 	if (uap->hdtr) {
1449 		error = copyin(uap->hdtr, &hdtr, sizeof(hdtr));
1450 		if (error)
1451 			goto done;
1452 		/*
1453 		 * Send any headers.
1454 		 */
1455 		if (hdtr.headers) {
1456 			error = iovec_copyin(hdtr.headers, &iov, aiov,
1457 					     hdtr.hdr_cnt, &hbytes);
1458 			if (error)
1459 				goto done;
1460 			auio.uio_iov = iov;
1461 			auio.uio_iovcnt = hdtr.hdr_cnt;
1462 			auio.uio_offset = 0;
1463 			auio.uio_segflg = UIO_USERSPACE;
1464 			auio.uio_rw = UIO_WRITE;
1465 			auio.uio_td = td;
1466 			auio.uio_resid = hbytes;
1467 
1468 			mheader = m_uiomove(&auio);
1469 
1470 			iovec_free(&iov, aiov);
1471 			if (mheader == NULL)
1472 				goto done;
1473 		}
1474 	}
1475 
1476 	error = kern_sendfile(vp, uap->s, uap->offset, uap->nbytes, mheader,
1477 	    &sbytes, uap->flags);
1478 	if (error)
1479 		goto done;
1480 
1481 	/*
1482 	 * Send trailers. Wimp out and use writev(2).
1483 	 */
1484 	if (uap->hdtr != NULL && hdtr.trailers != NULL) {
1485 		error = iovec_copyin(hdtr.trailers, &iov, aiov,
1486 				     hdtr.trl_cnt, &auio.uio_resid);
1487 		if (error)
1488 			goto done;
1489 		auio.uio_iov = iov;
1490 		auio.uio_iovcnt = hdtr.trl_cnt;
1491 		auio.uio_offset = 0;
1492 		auio.uio_segflg = UIO_USERSPACE;
1493 		auio.uio_rw = UIO_WRITE;
1494 		auio.uio_td = td;
1495 
1496 		error = kern_sendmsg(uap->s, NULL, &auio, NULL, 0, &tbytes);
1497 
1498 		iovec_free(&iov, aiov);
1499 		if (error)
1500 			goto done;
1501 		hdtr_size += tbytes;	/* trailer bytes successfully sent */
1502 	}
1503 
1504 done:
1505 	if (uap->sbytes != NULL) {
1506 		sbytes += hdtr_size;
1507 		copyout(&sbytes, uap->sbytes, sizeof(off_t));
1508 	}
1509 	if (vp)
1510 		vrele(vp);
1511 	return (error);
1512 }
1513 
1514 int
1515 kern_sendfile(struct vnode *vp, int sfd, off_t offset, size_t nbytes,
1516     struct mbuf *mheader, off_t *sbytes, int flags)
1517 {
1518 	struct thread *td = curthread;
1519 	struct proc *p = td->td_proc;
1520 	struct vm_object *obj;
1521 	struct socket *so;
1522 	struct file *fp;
1523 	struct mbuf *m;
1524 	struct sf_buf *sf;
1525 	struct sfbuf_mref *sfm;
1526 	struct vm_page *pg;
1527 	off_t off, xfsize;
1528 	off_t hbytes = 0;
1529 	int error = 0;
1530 
1531 	if (vp->v_type != VREG) {
1532 		error = EINVAL;
1533 		goto done0;
1534 	}
1535 	if ((obj = vp->v_object) == NULL) {
1536 		error = EINVAL;
1537 		goto done0;
1538 	}
1539 	error = holdsock(p->p_fd, sfd, &fp);
1540 	if (error)
1541 		goto done0;
1542 	so = (struct socket *)fp->f_data;
1543 	if (so->so_type != SOCK_STREAM) {
1544 		error = EINVAL;
1545 		goto done;
1546 	}
1547 	if ((so->so_state & SS_ISCONNECTED) == 0) {
1548 		error = ENOTCONN;
1549 		goto done;
1550 	}
1551 	if (offset < 0) {
1552 		error = EINVAL;
1553 		goto done;
1554 	}
1555 
1556 	*sbytes = 0;
1557 	/*
1558 	 * Protect against multiple writers to the socket.
1559 	 */
1560 	ssb_lock(&so->so_snd, M_WAITOK);
1561 
1562 	/*
1563 	 * Loop through the pages in the file, starting with the requested
1564 	 * offset. Get a file page (do I/O if necessary), map the file page
1565 	 * into an sf_buf, attach an mbuf header to the sf_buf, and queue
1566 	 * it on the socket.
1567 	 */
1568 	for (off = offset; ; off += xfsize, *sbytes += xfsize + hbytes) {
1569 		vm_pindex_t pindex;
1570 		vm_offset_t pgoff;
1571 
1572 		pindex = OFF_TO_IDX(off);
1573 retry_lookup:
1574 		/*
1575 		 * Calculate the amount to transfer. Not to exceed a page,
1576 		 * the EOF, or the passed in nbytes.
1577 		 */
1578 		xfsize = vp->v_filesize - off;
1579 		if (xfsize > PAGE_SIZE)
1580 			xfsize = PAGE_SIZE;
1581 		pgoff = (vm_offset_t)(off & PAGE_MASK);
1582 		if (PAGE_SIZE - pgoff < xfsize)
1583 			xfsize = PAGE_SIZE - pgoff;
1584 		if (nbytes && xfsize > (nbytes - *sbytes))
1585 			xfsize = nbytes - *sbytes;
1586 		if (xfsize <= 0)
1587 			break;
1588 		/*
1589 		 * Optimize the non-blocking case by looking at the socket space
1590 		 * before going to the extra work of constituting the sf_buf.
1591 		 */
1592 		if ((fp->f_flag & FNONBLOCK) && ssb_space(&so->so_snd) <= 0) {
1593 			if (so->so_state & SS_CANTSENDMORE)
1594 				error = EPIPE;
1595 			else
1596 				error = EAGAIN;
1597 			ssb_unlock(&so->so_snd);
1598 			goto done;
1599 		}
1600 		/*
1601 		 * Attempt to look up the page.
1602 		 *
1603 		 *	Allocate if not found, wait and loop if busy, then
1604 		 *	wire the page.  critical section protection is
1605 		 * 	required to maintain the object association (an
1606 		 *	interrupt can free the page) through to the
1607 		 *	vm_page_wire() call.
1608 		 */
1609 		crit_enter();
1610 		pg = vm_page_lookup(obj, pindex);
1611 		if (pg == NULL) {
1612 			pg = vm_page_alloc(obj, pindex, VM_ALLOC_NORMAL);
1613 			if (pg == NULL) {
1614 				vm_wait(0);
1615 				crit_exit();
1616 				goto retry_lookup;
1617 			}
1618 			vm_page_wakeup(pg);
1619 		} else if (vm_page_sleep_busy(pg, TRUE, "sfpbsy")) {
1620 			crit_exit();
1621 			goto retry_lookup;
1622 		}
1623 		vm_page_wire(pg);
1624 		crit_exit();
1625 
1626 		/*
1627 		 * If page is not valid for what we need, initiate I/O
1628 		 */
1629 
1630 		if (!pg->valid || !vm_page_is_valid(pg, pgoff, xfsize)) {
1631 			struct uio auio;
1632 			struct iovec aiov;
1633 			int bsize;
1634 
1635 			/*
1636 			 * Ensure that our page is still around when the I/O
1637 			 * completes.
1638 			 */
1639 			vm_page_io_start(pg);
1640 
1641 			/*
1642 			 * Get the page from backing store.
1643 			 */
1644 			bsize = vp->v_mount->mnt_stat.f_iosize;
1645 			auio.uio_iov = &aiov;
1646 			auio.uio_iovcnt = 1;
1647 			aiov.iov_base = 0;
1648 			aiov.iov_len = MAXBSIZE;
1649 			auio.uio_resid = MAXBSIZE;
1650 			auio.uio_offset = trunc_page(off);
1651 			auio.uio_segflg = UIO_NOCOPY;
1652 			auio.uio_rw = UIO_READ;
1653 			auio.uio_td = td;
1654 			vn_lock(vp, LK_SHARED | LK_RETRY);
1655 			error = VOP_READ(vp, &auio,
1656 				    IO_VMIO | ((MAXBSIZE / bsize) << 16),
1657 				    p->p_ucred);
1658 			vn_unlock(vp);
1659 			vm_page_flag_clear(pg, PG_ZERO);
1660 			vm_page_io_finish(pg);
1661 			if (error) {
1662 				crit_enter();
1663 				vm_page_unwire(pg, 0);
1664 				vm_page_try_to_free(pg);
1665 				crit_exit();
1666 				ssb_unlock(&so->so_snd);
1667 				goto done;
1668 			}
1669 		}
1670 
1671 
1672 		/*
1673 		 * Get a sendfile buf. We usually wait as long as necessary,
1674 		 * but this wait can be interrupted.
1675 		 */
1676 		if ((sf = sf_buf_alloc(pg, SFB_CATCH)) == NULL) {
1677 			crit_enter();
1678 			vm_page_unwire(pg, 0);
1679 			vm_page_try_to_free(pg);
1680 			crit_exit();
1681 			ssb_unlock(&so->so_snd);
1682 			error = EINTR;
1683 			goto done;
1684 		}
1685 
1686 		/*
1687 		 * Get an mbuf header and set it up as having external storage.
1688 		 */
1689 		MGETHDR(m, MB_WAIT, MT_DATA);
1690 		if (m == NULL) {
1691 			error = ENOBUFS;
1692 			sf_buf_free(sf);
1693 			ssb_unlock(&so->so_snd);
1694 			goto done;
1695 		}
1696 
1697 		/*
1698 		 * sfm is a temporary hack, use a per-cpu cache for this.
1699 		 */
1700 		sfm = kmalloc(sizeof(struct sfbuf_mref), M_SENDFILE, M_WAITOK);
1701 		sfm->sf = sf;
1702 		sfm->mref_count = 1;
1703 		lwkt_serialize_init(&sfm->serializer);
1704 
1705 		m->m_ext.ext_free = sf_buf_mfree;
1706 		m->m_ext.ext_ref = sf_buf_mref;
1707 		m->m_ext.ext_arg = sfm;
1708 		m->m_ext.ext_buf = (void *)sf->kva;
1709 		m->m_ext.ext_size = PAGE_SIZE;
1710 		m->m_data = (char *) sf->kva + pgoff;
1711 		m->m_flags |= M_EXT;
1712 		m->m_pkthdr.len = m->m_len = xfsize;
1713 		KKASSERT((m->m_flags & (M_EXT_CLUSTER)) == 0);
1714 
1715 		if (mheader != NULL) {
1716 			hbytes = mheader->m_pkthdr.len;
1717 			mheader->m_pkthdr.len += m->m_pkthdr.len;
1718 			m_cat(mheader, m);
1719 			m = mheader;
1720 			mheader = NULL;
1721 		} else
1722 			hbytes = 0;
1723 
1724 		/*
1725 		 * Add the buffer to the socket buffer chain.
1726 		 */
1727 		crit_enter();
1728 retry_space:
1729 		/*
1730 		 * Make sure that the socket is still able to take more data.
1731 		 * CANTSENDMORE being true usually means that the connection
1732 		 * was closed. so_error is true when an error was sensed after
1733 		 * a previous send.
1734 		 * The state is checked after the page mapping and buffer
1735 		 * allocation above since those operations may block and make
1736 		 * any socket checks stale. From this point forward, nothing
1737 		 * blocks before the pru_send (or more accurately, any blocking
1738 		 * results in a loop back to here to re-check).
1739 		 */
1740 		if ((so->so_state & SS_CANTSENDMORE) || so->so_error) {
1741 			if (so->so_state & SS_CANTSENDMORE) {
1742 				error = EPIPE;
1743 			} else {
1744 				error = so->so_error;
1745 				so->so_error = 0;
1746 			}
1747 			m_freem(m);
1748 			ssb_unlock(&so->so_snd);
1749 			crit_exit();
1750 			goto done;
1751 		}
1752 		/*
1753 		 * Wait for socket space to become available. We do this just
1754 		 * after checking the connection state above in order to avoid
1755 		 * a race condition with ssb_wait().
1756 		 */
1757 		if (ssb_space(&so->so_snd) < so->so_snd.ssb_lowat) {
1758 			if (fp->f_flag & FNONBLOCK) {
1759 				m_freem(m);
1760 				ssb_unlock(&so->so_snd);
1761 				crit_exit();
1762 				error = EAGAIN;
1763 				goto done;
1764 			}
1765 			error = ssb_wait(&so->so_snd);
1766 			/*
1767 			 * An error from ssb_wait usually indicates that we've
1768 			 * been interrupted by a signal. If we've sent anything
1769 			 * then return bytes sent, otherwise return the error.
1770 			 */
1771 			if (error) {
1772 				m_freem(m);
1773 				ssb_unlock(&so->so_snd);
1774 				crit_exit();
1775 				goto done;
1776 			}
1777 			goto retry_space;
1778 		}
1779 		error = so_pru_send(so, 0, m, NULL, NULL, td);
1780 		crit_exit();
1781 		if (error) {
1782 			ssb_unlock(&so->so_snd);
1783 			goto done;
1784 		}
1785 	}
1786 	if (mheader != NULL) {
1787 		*sbytes += mheader->m_pkthdr.len;
1788 		error = so_pru_send(so, 0, mheader, NULL, NULL, td);
1789 		mheader = NULL;
1790 	}
1791 	ssb_unlock(&so->so_snd);
1792 
1793 done:
1794 	fdrop(fp);
1795 done0:
1796 	if (mheader != NULL)
1797 		m_freem(mheader);
1798 	return (error);
1799 }
1800 
1801 int
1802 sys_sctp_peeloff(struct sctp_peeloff_args *uap)
1803 {
1804 #ifdef SCTP
1805 	struct thread *td = curthread;
1806 	struct proc *p = td->td_proc;
1807 	struct file *lfp = NULL;
1808 	struct file *nfp = NULL;
1809 	int error;
1810 	struct socket *head, *so;
1811 	caddr_t assoc_id;
1812 	int fd;
1813 	short fflag;		/* type must match fp->f_flag */
1814 
1815 	assoc_id = uap->name;
1816 	error = holdsock(p->p_fd, uap->sd, &lfp);
1817 	if (error) {
1818 		return (error);
1819 	}
1820 	crit_enter();
1821 	head = (struct socket *)lfp->f_data;
1822 	error = sctp_can_peel_off(head, assoc_id);
1823 	if (error) {
1824 		crit_exit();
1825 		goto done;
1826 	}
1827 	/*
1828 	 * At this point we know we do have a assoc to pull
1829 	 * we proceed to get the fd setup. This may block
1830 	 * but that is ok.
1831 	 */
1832 
1833 	fflag = lfp->f_flag;
1834 	error = falloc(p, &nfp, &fd);
1835 	if (error) {
1836 		/*
1837 		 * Probably ran out of file descriptors. Put the
1838 		 * unaccepted connection back onto the queue and
1839 		 * do another wakeup so some other process might
1840 		 * have a chance at it.
1841 		 */
1842 		crit_exit();
1843 		goto done;
1844 	}
1845 	uap->sysmsg_result = fd;
1846 
1847 	so = sctp_get_peeloff(head, assoc_id, &error);
1848 	if (so == NULL) {
1849 		/*
1850 		 * Either someone else peeled it off OR
1851 		 * we can't get a socket.
1852 		 */
1853 		goto noconnection;
1854 	}
1855 	so->so_state &= ~SS_COMP;
1856 	so->so_state &= ~SS_NOFDREF;
1857 	so->so_head = NULL;
1858 	if (head->so_sigio != NULL)
1859 		fsetown(fgetown(head->so_sigio), &so->so_sigio);
1860 
1861 	nfp->f_type = DTYPE_SOCKET;
1862 	nfp->f_flag = fflag;
1863 	nfp->f_ops = &socketops;
1864 	nfp->f_data = so;
1865 
1866 noconnection:
1867 	/*
1868 	 * Assign the file pointer to the reserved descriptor, or clear
1869 	 * the reserved descriptor if an error occured.
1870 	 */
1871 	if (error)
1872 		fsetfd(p, NULL, fd);
1873 	else
1874 		fsetfd(p, nfp, fd);
1875 	crit_exit();
1876 	/*
1877 	 * Release explicitly held references before returning.
1878 	 */
1879 done:
1880 	if (nfp != NULL)
1881 		fdrop(nfp);
1882 	fdrop(lfp);
1883 	return (error);
1884 #else /* SCTP */
1885 	return(EOPNOTSUPP);
1886 #endif /* SCTP */
1887 }
1888