uipc_usrreq.c revision 93076
1/*
2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	From: @(#)uipc_usrreq.c	8.3 (Berkeley) 1/4/94
34 * $FreeBSD: head/sys/kern/uipc_usrreq.c 93076 2002-03-24 05:09:11Z bde $
35 */
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/kernel.h>
40#include <sys/fcntl.h>
41#include <sys/domain.h>
42#include <sys/filedesc.h>
43#include <sys/lock.h>
44#include <sys/malloc.h>		/* XXX must be before <sys/file.h> */
45#include <sys/file.h>
46#include <sys/mutex.h>
47#include <sys/mbuf.h>
48#include <sys/namei.h>
49#include <sys/proc.h>
50#include <sys/protosw.h>
51#include <sys/socket.h>
52#include <sys/socketvar.h>
53#include <sys/resourcevar.h>
54#include <sys/stat.h>
55#include <sys/sysctl.h>
56#include <sys/un.h>
57#include <sys/unpcb.h>
58#include <sys/vnode.h>
59#include <sys/jail.h>
60#include <sys/sx.h>
61
62#include <vm/uma.h>
63
64static uma_zone_t unp_zone;
65static	unp_gen_t unp_gencnt;
66static	u_int unp_count;
67
68static	struct unp_head unp_shead, unp_dhead;
69
70/*
71 * Unix communications domain.
72 *
73 * TODO:
74 *	SEQPACKET, RDM
75 *	rethink name space problems
76 *	need a proper out-of-band
77 *	lock pushdown
78 */
79static struct	sockaddr sun_noname = { sizeof(sun_noname), AF_LOCAL };
80static ino_t	unp_ino;		/* prototype for fake inode numbers */
81
82static int     unp_attach(struct socket *);
83static void    unp_detach(struct unpcb *);
84static int     unp_bind(struct unpcb *,struct sockaddr *, struct thread *);
85static int     unp_connect(struct socket *,struct sockaddr *, struct thread *);
86static void    unp_disconnect(struct unpcb *);
87static void    unp_shutdown(struct unpcb *);
88static void    unp_drop(struct unpcb *, int);
89static void    unp_gc(void);
90static void    unp_scan(struct mbuf *, void (*)(struct file *));
91static void    unp_mark(struct file *);
92static void    unp_discard(struct file *);
93static void    unp_freerights(struct file **, int);
94static int     unp_internalize(struct mbuf **, struct thread *);
95static int     unp_listen(struct unpcb *, struct thread *);
96
97static int
98uipc_abort(struct socket *so)
99{
100	struct unpcb *unp = sotounpcb(so);
101
102	if (unp == 0)
103		return EINVAL;
104	unp_drop(unp, ECONNABORTED);
105	unp_detach(unp);
106	sotryfree(so);
107	return 0;
108}
109
110static int
111uipc_accept(struct socket *so, struct sockaddr **nam)
112{
113	struct unpcb *unp = sotounpcb(so);
114
115	if (unp == 0)
116		return EINVAL;
117
118	/*
119	 * Pass back name of connected socket,
120	 * if it was bound and we are still connected
121	 * (our peer may have closed already!).
122	 */
123	if (unp->unp_conn && unp->unp_conn->unp_addr) {
124		*nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr,
125				    1);
126	} else {
127		*nam = dup_sockaddr((struct sockaddr *)&sun_noname, 1);
128	}
129	return 0;
130}
131
132static int
133uipc_attach(struct socket *so, int proto, struct thread *td)
134{
135	struct unpcb *unp = sotounpcb(so);
136
137	if (unp != 0)
138		return EISCONN;
139	return unp_attach(so);
140}
141
142static int
143uipc_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
144{
145	struct unpcb *unp = sotounpcb(so);
146
147	if (unp == 0)
148		return EINVAL;
149
150	return unp_bind(unp, nam, td);
151}
152
153static int
154uipc_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
155{
156	struct unpcb *unp = sotounpcb(so);
157
158	if (unp == 0)
159		return EINVAL;
160	return unp_connect(so, nam, curthread);
161}
162
163static int
164uipc_connect2(struct socket *so1, struct socket *so2)
165{
166	struct unpcb *unp = sotounpcb(so1);
167
168	if (unp == 0)
169		return EINVAL;
170
171	return unp_connect2(so1, so2);
172}
173
174/* control is EOPNOTSUPP */
175
176static int
177uipc_detach(struct socket *so)
178{
179	struct unpcb *unp = sotounpcb(so);
180
181	if (unp == 0)
182		return EINVAL;
183
184	unp_detach(unp);
185	return 0;
186}
187
188static int
189uipc_disconnect(struct socket *so)
190{
191	struct unpcb *unp = sotounpcb(so);
192
193	if (unp == 0)
194		return EINVAL;
195	unp_disconnect(unp);
196	return 0;
197}
198
199static int
200uipc_listen(struct socket *so, struct thread *td)
201{
202	struct unpcb *unp = sotounpcb(so);
203
204	if (unp == 0 || unp->unp_vnode == 0)
205		return EINVAL;
206	return unp_listen(unp, td);
207}
208
209static int
210uipc_peeraddr(struct socket *so, struct sockaddr **nam)
211{
212	struct unpcb *unp = sotounpcb(so);
213
214	if (unp == 0)
215		return EINVAL;
216	if (unp->unp_conn && unp->unp_conn->unp_addr)
217		*nam = dup_sockaddr((struct sockaddr *)unp->unp_conn->unp_addr,
218				    1);
219	return 0;
220}
221
222static int
223uipc_rcvd(struct socket *so, int flags)
224{
225	struct unpcb *unp = sotounpcb(so);
226	struct socket *so2;
227	u_long newhiwat;
228
229	if (unp == 0)
230		return EINVAL;
231	switch (so->so_type) {
232	case SOCK_DGRAM:
233		panic("uipc_rcvd DGRAM?");
234		/*NOTREACHED*/
235
236	case SOCK_STREAM:
237		if (unp->unp_conn == 0)
238			break;
239		so2 = unp->unp_conn->unp_socket;
240		/*
241		 * Adjust backpressure on sender
242		 * and wakeup any waiting to write.
243		 */
244		so2->so_snd.sb_mbmax += unp->unp_mbcnt - so->so_rcv.sb_mbcnt;
245		unp->unp_mbcnt = so->so_rcv.sb_mbcnt;
246		newhiwat = so2->so_snd.sb_hiwat + unp->unp_cc -
247		    so->so_rcv.sb_cc;
248		(void)chgsbsize(so2->so_cred->cr_uidinfo, &so2->so_snd.sb_hiwat,
249		    newhiwat, RLIM_INFINITY);
250		unp->unp_cc = so->so_rcv.sb_cc;
251		sowwakeup(so2);
252		break;
253
254	default:
255		panic("uipc_rcvd unknown socktype");
256	}
257	return 0;
258}
259
260/* pru_rcvoob is EOPNOTSUPP */
261
262static int
263uipc_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
264	  struct mbuf *control, struct thread *td)
265{
266	int error = 0;
267	struct unpcb *unp = sotounpcb(so);
268	struct socket *so2;
269	u_long newhiwat;
270
271	if (unp == 0) {
272		error = EINVAL;
273		goto release;
274	}
275	if (flags & PRUS_OOB) {
276		error = EOPNOTSUPP;
277		goto release;
278	}
279
280	if (control && (error = unp_internalize(&control, td)))
281		goto release;
282
283	switch (so->so_type) {
284	case SOCK_DGRAM:
285	{
286		struct sockaddr *from;
287
288		if (nam) {
289			if (unp->unp_conn) {
290				error = EISCONN;
291				break;
292			}
293			error = unp_connect(so, nam, td);
294			if (error)
295				break;
296		} else {
297			if (unp->unp_conn == 0) {
298				error = ENOTCONN;
299				break;
300			}
301		}
302		so2 = unp->unp_conn->unp_socket;
303		if (unp->unp_addr)
304			from = (struct sockaddr *)unp->unp_addr;
305		else
306			from = &sun_noname;
307		if (sbappendaddr(&so2->so_rcv, from, m, control)) {
308			sorwakeup(so2);
309			m = 0;
310			control = 0;
311		} else
312			error = ENOBUFS;
313		if (nam)
314			unp_disconnect(unp);
315		break;
316	}
317
318	case SOCK_STREAM:
319		/* Connect if not connected yet. */
320		/*
321		 * Note: A better implementation would complain
322		 * if not equal to the peer's address.
323		 */
324		if ((so->so_state & SS_ISCONNECTED) == 0) {
325			if (nam) {
326				error = unp_connect(so, nam, td);
327				if (error)
328					break;	/* XXX */
329			} else {
330				error = ENOTCONN;
331				break;
332			}
333		}
334
335		if (so->so_state & SS_CANTSENDMORE) {
336			error = EPIPE;
337			break;
338		}
339		if (unp->unp_conn == 0)
340			panic("uipc_send connected but no connection?");
341		so2 = unp->unp_conn->unp_socket;
342		/*
343		 * Send to paired receive port, and then reduce
344		 * send buffer hiwater marks to maintain backpressure.
345		 * Wake up readers.
346		 */
347		if (control) {
348			if (sbappendcontrol(&so2->so_rcv, m, control))
349				control = 0;
350		} else
351			sbappend(&so2->so_rcv, m);
352		so->so_snd.sb_mbmax -=
353			so2->so_rcv.sb_mbcnt - unp->unp_conn->unp_mbcnt;
354		unp->unp_conn->unp_mbcnt = so2->so_rcv.sb_mbcnt;
355		newhiwat = so->so_snd.sb_hiwat -
356		    (so2->so_rcv.sb_cc - unp->unp_conn->unp_cc);
357		(void)chgsbsize(so->so_cred->cr_uidinfo, &so->so_snd.sb_hiwat,
358		    newhiwat, RLIM_INFINITY);
359		unp->unp_conn->unp_cc = so2->so_rcv.sb_cc;
360		sorwakeup(so2);
361		m = 0;
362		break;
363
364	default:
365		panic("uipc_send unknown socktype");
366	}
367
368	/*
369	 * SEND_EOF is equivalent to a SEND followed by
370	 * a SHUTDOWN.
371	 */
372	if (flags & PRUS_EOF) {
373		socantsendmore(so);
374		unp_shutdown(unp);
375	}
376
377	if (control && error != 0)
378		unp_dispose(control);
379
380release:
381	if (control)
382		m_freem(control);
383	if (m)
384		m_freem(m);
385	return error;
386}
387
388static int
389uipc_sense(struct socket *so, struct stat *sb)
390{
391	struct unpcb *unp = sotounpcb(so);
392	struct socket *so2;
393
394	if (unp == 0)
395		return EINVAL;
396	sb->st_blksize = so->so_snd.sb_hiwat;
397	if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) {
398		so2 = unp->unp_conn->unp_socket;
399		sb->st_blksize += so2->so_rcv.sb_cc;
400	}
401	sb->st_dev = NOUDEV;
402	if (unp->unp_ino == 0)
403		unp->unp_ino = unp_ino++;
404	sb->st_ino = unp->unp_ino;
405	return (0);
406}
407
408static int
409uipc_shutdown(struct socket *so)
410{
411	struct unpcb *unp = sotounpcb(so);
412
413	if (unp == 0)
414		return EINVAL;
415	socantsendmore(so);
416	unp_shutdown(unp);
417	return 0;
418}
419
420static int
421uipc_sockaddr(struct socket *so, struct sockaddr **nam)
422{
423	struct unpcb *unp = sotounpcb(so);
424
425	if (unp == 0)
426		return EINVAL;
427	if (unp->unp_addr)
428		*nam = dup_sockaddr((struct sockaddr *)unp->unp_addr, 1);
429	else
430		*nam = dup_sockaddr((struct sockaddr *)&sun_noname, 1);
431	return 0;
432}
433
434struct pr_usrreqs uipc_usrreqs = {
435	uipc_abort, uipc_accept, uipc_attach, uipc_bind, uipc_connect,
436	uipc_connect2, pru_control_notsupp, uipc_detach, uipc_disconnect,
437	uipc_listen, uipc_peeraddr, uipc_rcvd, pru_rcvoob_notsupp,
438	uipc_send, uipc_sense, uipc_shutdown, uipc_sockaddr,
439	sosend, soreceive, sopoll
440};
441
442int
443uipc_ctloutput(so, sopt)
444	struct socket *so;
445	struct sockopt *sopt;
446{
447	struct unpcb *unp = sotounpcb(so);
448	int error;
449
450	switch (sopt->sopt_dir) {
451	case SOPT_GET:
452		switch (sopt->sopt_name) {
453		case LOCAL_PEERCRED:
454			if (unp->unp_flags & UNP_HAVEPC)
455				error = sooptcopyout(sopt, &unp->unp_peercred,
456				    sizeof(unp->unp_peercred));
457			else {
458				if (so->so_type == SOCK_STREAM)
459					error = ENOTCONN;
460				else
461					error = EINVAL;
462			}
463			break;
464		default:
465			error = EOPNOTSUPP;
466			break;
467		}
468		break;
469	case SOPT_SET:
470	default:
471		error = EOPNOTSUPP;
472		break;
473	}
474	return (error);
475}
476
477/*
478 * Both send and receive buffers are allocated PIPSIZ bytes of buffering
479 * for stream sockets, although the total for sender and receiver is
480 * actually only PIPSIZ.
481 * Datagram sockets really use the sendspace as the maximum datagram size,
482 * and don't really want to reserve the sendspace.  Their recvspace should
483 * be large enough for at least one max-size datagram plus address.
484 */
485#ifndef PIPSIZ
486#define	PIPSIZ	8192
487#endif
488static u_long	unpst_sendspace = PIPSIZ;
489static u_long	unpst_recvspace = PIPSIZ;
490static u_long	unpdg_sendspace = 2*1024;	/* really max datagram size */
491static u_long	unpdg_recvspace = 4*1024;
492
493static int	unp_rights;			/* file descriptors in flight */
494
495SYSCTL_DECL(_net_local_stream);
496SYSCTL_INT(_net_local_stream, OID_AUTO, sendspace, CTLFLAG_RW,
497	   &unpst_sendspace, 0, "");
498SYSCTL_INT(_net_local_stream, OID_AUTO, recvspace, CTLFLAG_RW,
499	   &unpst_recvspace, 0, "");
500SYSCTL_DECL(_net_local_dgram);
501SYSCTL_INT(_net_local_dgram, OID_AUTO, maxdgram, CTLFLAG_RW,
502	   &unpdg_sendspace, 0, "");
503SYSCTL_INT(_net_local_dgram, OID_AUTO, recvspace, CTLFLAG_RW,
504	   &unpdg_recvspace, 0, "");
505SYSCTL_DECL(_net_local);
506SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0, "");
507
508static int
509unp_attach(so)
510	struct socket *so;
511{
512	register struct unpcb *unp;
513	int error;
514
515	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
516		switch (so->so_type) {
517
518		case SOCK_STREAM:
519			error = soreserve(so, unpst_sendspace, unpst_recvspace);
520			break;
521
522		case SOCK_DGRAM:
523			error = soreserve(so, unpdg_sendspace, unpdg_recvspace);
524			break;
525
526		default:
527			panic("unp_attach");
528		}
529		if (error)
530			return (error);
531	}
532	unp = uma_zalloc(unp_zone, M_WAITOK);
533	if (unp == NULL)
534		return (ENOBUFS);
535	bzero(unp, sizeof *unp);
536	unp->unp_gencnt = ++unp_gencnt;
537	unp_count++;
538	LIST_INIT(&unp->unp_refs);
539	unp->unp_socket = so;
540	FILEDESC_LOCK(curproc->p_fd);
541	unp->unp_rvnode = curthread->td_proc->p_fd->fd_rdir;
542	FILEDESC_UNLOCK(curproc->p_fd);
543	LIST_INSERT_HEAD(so->so_type == SOCK_DGRAM ? &unp_dhead
544			 : &unp_shead, unp, unp_link);
545	so->so_pcb = (caddr_t)unp;
546	return (0);
547}
548
549static void
550unp_detach(unp)
551	register struct unpcb *unp;
552{
553	LIST_REMOVE(unp, unp_link);
554	unp->unp_gencnt = ++unp_gencnt;
555	--unp_count;
556	if (unp->unp_vnode) {
557		unp->unp_vnode->v_socket = 0;
558		vrele(unp->unp_vnode);
559		unp->unp_vnode = 0;
560	}
561	if (unp->unp_conn)
562		unp_disconnect(unp);
563	while (!LIST_EMPTY(&unp->unp_refs))
564		unp_drop(LIST_FIRST(&unp->unp_refs), ECONNRESET);
565	soisdisconnected(unp->unp_socket);
566	unp->unp_socket->so_pcb = 0;
567	if (unp_rights) {
568		/*
569		 * Normally the receive buffer is flushed later,
570		 * in sofree, but if our receive buffer holds references
571		 * to descriptors that are now garbage, we will dispose
572		 * of those descriptor references after the garbage collector
573		 * gets them (resulting in a "panic: closef: count < 0").
574		 */
575		sorflush(unp->unp_socket);
576		unp_gc();
577	}
578	if (unp->unp_addr)
579		FREE(unp->unp_addr, M_SONAME);
580	uma_zfree(unp_zone, unp);
581}
582
583static int
584unp_bind(unp, nam, td)
585	struct unpcb *unp;
586	struct sockaddr *nam;
587	struct thread *td;
588{
589	struct sockaddr_un *soun = (struct sockaddr_un *)nam;
590	struct vnode *vp;
591	struct mount *mp;
592	struct vattr vattr;
593	int error, namelen;
594	struct nameidata nd;
595	char *buf;
596
597	if (unp->unp_vnode != NULL)
598		return (EINVAL);
599	namelen = soun->sun_len - offsetof(struct sockaddr_un, sun_path);
600	if (namelen <= 0)
601		return EINVAL;
602	buf = malloc(SOCK_MAXADDRLEN, M_TEMP, M_WAITOK);
603	strncpy(buf, soun->sun_path, namelen);
604	buf[namelen] = 0;	/* null-terminate the string */
605restart:
606	NDINIT(&nd, CREATE, NOFOLLOW | LOCKPARENT, UIO_SYSSPACE,
607	    buf, td);
608/* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */
609	error = namei(&nd);
610	if (error) {
611		free(buf, M_TEMP);
612		return (error);
613	}
614	vp = nd.ni_vp;
615	if (vp != NULL || vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
616		NDFREE(&nd, NDF_ONLY_PNBUF);
617		if (nd.ni_dvp == vp)
618			vrele(nd.ni_dvp);
619		else
620			vput(nd.ni_dvp);
621		if (vp != NULL) {
622			vrele(vp);
623			free(buf, M_TEMP);
624			return (EADDRINUSE);
625		}
626		error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH);
627		if (error) {
628			free(buf, M_TEMP);
629			return (error);
630		}
631		goto restart;
632	}
633	VATTR_NULL(&vattr);
634	vattr.va_type = VSOCK;
635	FILEDESC_LOCK(td->td_proc->p_fd);
636	vattr.va_mode = (ACCESSPERMS & ~td->td_proc->p_fd->fd_cmask);
637	FILEDESC_UNLOCK(td->td_proc->p_fd);
638	VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
639	error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
640	NDFREE(&nd, NDF_ONLY_PNBUF);
641	vput(nd.ni_dvp);
642	if (error) {
643		free(buf, M_TEMP);
644		return (error);
645	}
646	vp = nd.ni_vp;
647	vp->v_socket = unp->unp_socket;
648	unp->unp_vnode = vp;
649	unp->unp_addr = (struct sockaddr_un *)dup_sockaddr(nam, 1);
650	VOP_UNLOCK(vp, 0, td);
651	vn_finished_write(mp);
652	free(buf, M_TEMP);
653	return (0);
654}
655
656static int
657unp_connect(so, nam, td)
658	struct socket *so;
659	struct sockaddr *nam;
660	struct thread *td;
661{
662	register struct sockaddr_un *soun = (struct sockaddr_un *)nam;
663	register struct vnode *vp;
664	register struct socket *so2, *so3;
665	struct unpcb *unp, *unp2, *unp3;
666	int error, len;
667	struct nameidata nd;
668	char buf[SOCK_MAXADDRLEN];
669
670	len = nam->sa_len - offsetof(struct sockaddr_un, sun_path);
671	if (len <= 0)
672		return EINVAL;
673	strncpy(buf, soun->sun_path, len);
674	buf[len] = 0;
675
676	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, buf, td);
677	error = namei(&nd);
678	if (error)
679		return (error);
680	vp = nd.ni_vp;
681	NDFREE(&nd, NDF_ONLY_PNBUF);
682	if (vp->v_type != VSOCK) {
683		error = ENOTSOCK;
684		goto bad;
685	}
686	error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td);
687	if (error)
688		goto bad;
689	so2 = vp->v_socket;
690	if (so2 == 0) {
691		error = ECONNREFUSED;
692		goto bad;
693	}
694	if (so->so_type != so2->so_type) {
695		error = EPROTOTYPE;
696		goto bad;
697	}
698	if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
699		if ((so2->so_options & SO_ACCEPTCONN) == 0 ||
700		    (so3 = sonewconn(so2, 0)) == 0) {
701			error = ECONNREFUSED;
702			goto bad;
703		}
704		unp = sotounpcb(so);
705		unp2 = sotounpcb(so2);
706		unp3 = sotounpcb(so3);
707		if (unp2->unp_addr)
708			unp3->unp_addr = (struct sockaddr_un *)
709				dup_sockaddr((struct sockaddr *)
710					     unp2->unp_addr, 1);
711
712		/*
713		 * unp_peercred management:
714		 *
715		 * The connecter's (client's) credentials are copied
716		 * from its process structure at the time of connect()
717		 * (which is now).
718		 */
719		cru2x(td->td_ucred, &unp3->unp_peercred);
720		unp3->unp_flags |= UNP_HAVEPC;
721		/*
722		 * The receiver's (server's) credentials are copied
723		 * from the unp_peercred member of socket on which the
724		 * former called listen(); unp_listen() cached that
725		 * process's credentials at that time so we can use
726		 * them now.
727		 */
728		KASSERT(unp2->unp_flags & UNP_HAVEPCCACHED,
729		    ("unp_connect: listener without cached peercred"));
730		memcpy(&unp->unp_peercred, &unp2->unp_peercred,
731		    sizeof(unp->unp_peercred));
732		unp->unp_flags |= UNP_HAVEPC;
733
734		so2 = so3;
735	}
736	error = unp_connect2(so, so2);
737bad:
738	vput(vp);
739	return (error);
740}
741
742int
743unp_connect2(so, so2)
744	register struct socket *so;
745	register struct socket *so2;
746{
747	register struct unpcb *unp = sotounpcb(so);
748	register struct unpcb *unp2;
749
750	if (so2->so_type != so->so_type)
751		return (EPROTOTYPE);
752	unp2 = sotounpcb(so2);
753	unp->unp_conn = unp2;
754	switch (so->so_type) {
755
756	case SOCK_DGRAM:
757		LIST_INSERT_HEAD(&unp2->unp_refs, unp, unp_reflink);
758		soisconnected(so);
759		break;
760
761	case SOCK_STREAM:
762		unp2->unp_conn = unp;
763		soisconnected(so);
764		soisconnected(so2);
765		break;
766
767	default:
768		panic("unp_connect2");
769	}
770	return (0);
771}
772
773static void
774unp_disconnect(unp)
775	struct unpcb *unp;
776{
777	register struct unpcb *unp2 = unp->unp_conn;
778
779	if (unp2 == 0)
780		return;
781	unp->unp_conn = 0;
782	switch (unp->unp_socket->so_type) {
783
784	case SOCK_DGRAM:
785		LIST_REMOVE(unp, unp_reflink);
786		unp->unp_socket->so_state &= ~SS_ISCONNECTED;
787		break;
788
789	case SOCK_STREAM:
790		soisdisconnected(unp->unp_socket);
791		unp2->unp_conn = 0;
792		soisdisconnected(unp2->unp_socket);
793		break;
794	}
795}
796
797#ifdef notdef
798void
799unp_abort(unp)
800	struct unpcb *unp;
801{
802
803	unp_detach(unp);
804}
805#endif
806
807static int
808unp_pcblist(SYSCTL_HANDLER_ARGS)
809{
810	int error, i, n;
811	struct unpcb *unp, **unp_list;
812	unp_gen_t gencnt;
813	struct xunpgen *xug;
814	struct unp_head *head;
815	struct xunpcb *xu;
816
817	head = ((intptr_t)arg1 == SOCK_DGRAM ? &unp_dhead : &unp_shead);
818
819	/*
820	 * The process of preparing the PCB list is too time-consuming and
821	 * resource-intensive to repeat twice on every request.
822	 */
823	if (req->oldptr == 0) {
824		n = unp_count;
825		req->oldidx = 2 * (sizeof *xug)
826			+ (n + n/8) * sizeof(struct xunpcb);
827		return 0;
828	}
829
830	if (req->newptr != 0)
831		return EPERM;
832
833	/*
834	 * OK, now we're committed to doing something.
835	 */
836	xug = malloc(sizeof(*xug), M_TEMP, M_WAITOK);
837	gencnt = unp_gencnt;
838	n = unp_count;
839
840	xug->xug_len = sizeof *xug;
841	xug->xug_count = n;
842	xug->xug_gen = gencnt;
843	xug->xug_sogen = so_gencnt;
844	error = SYSCTL_OUT(req, xug, sizeof *xug);
845	if (error) {
846		free(xug, M_TEMP);
847		return error;
848	}
849
850	unp_list = malloc(n * sizeof *unp_list, M_TEMP, M_WAITOK);
851
852	for (unp = LIST_FIRST(head), i = 0; unp && i < n;
853	     unp = LIST_NEXT(unp, unp_link)) {
854		if (unp->unp_gencnt <= gencnt) {
855			if (cr_cansee(req->td->td_ucred,
856			    unp->unp_socket->so_cred))
857				continue;
858			unp_list[i++] = unp;
859		}
860	}
861	n = i;			/* in case we lost some during malloc */
862
863	error = 0;
864	xu = malloc(sizeof(*xu), M_TEMP, M_WAITOK);
865	for (i = 0; i < n; i++) {
866		unp = unp_list[i];
867		if (unp->unp_gencnt <= gencnt) {
868			xu->xu_len = sizeof *xu;
869			xu->xu_unpp = unp;
870			/*
871			 * XXX - need more locking here to protect against
872			 * connect/disconnect races for SMP.
873			 */
874			if (unp->unp_addr)
875				bcopy(unp->unp_addr, &xu->xu_addr,
876				      unp->unp_addr->sun_len);
877			if (unp->unp_conn && unp->unp_conn->unp_addr)
878				bcopy(unp->unp_conn->unp_addr,
879				      &xu->xu_caddr,
880				      unp->unp_conn->unp_addr->sun_len);
881			bcopy(unp, &xu->xu_unp, sizeof *unp);
882			sotoxsocket(unp->unp_socket, &xu->xu_socket);
883			error = SYSCTL_OUT(req, xu, sizeof *xu);
884		}
885	}
886	free(xu, M_TEMP);
887	if (!error) {
888		/*
889		 * Give the user an updated idea of our state.
890		 * If the generation differs from what we told
891		 * her before, she knows that something happened
892		 * while we were processing this request, and it
893		 * might be necessary to retry.
894		 */
895		xug->xug_gen = unp_gencnt;
896		xug->xug_sogen = so_gencnt;
897		xug->xug_count = unp_count;
898		error = SYSCTL_OUT(req, xug, sizeof *xug);
899	}
900	free(unp_list, M_TEMP);
901	free(xug, M_TEMP);
902	return error;
903}
904
905SYSCTL_PROC(_net_local_dgram, OID_AUTO, pcblist, CTLFLAG_RD,
906	    (caddr_t)(long)SOCK_DGRAM, 0, unp_pcblist, "S,xunpcb",
907	    "List of active local datagram sockets");
908SYSCTL_PROC(_net_local_stream, OID_AUTO, pcblist, CTLFLAG_RD,
909	    (caddr_t)(long)SOCK_STREAM, 0, unp_pcblist, "S,xunpcb",
910	    "List of active local stream sockets");
911
912static void
913unp_shutdown(unp)
914	struct unpcb *unp;
915{
916	struct socket *so;
917
918	if (unp->unp_socket->so_type == SOCK_STREAM && unp->unp_conn &&
919	    (so = unp->unp_conn->unp_socket))
920		socantrcvmore(so);
921}
922
923static void
924unp_drop(unp, errno)
925	struct unpcb *unp;
926	int errno;
927{
928	struct socket *so = unp->unp_socket;
929
930	so->so_error = errno;
931	unp_disconnect(unp);
932}
933
934#ifdef notdef
935void
936unp_drain()
937{
938
939}
940#endif
941
942static void
943unp_freerights(rp, fdcount)
944	struct file **rp;
945	int fdcount;
946{
947	int i;
948	struct file *fp;
949
950	for (i = 0; i < fdcount; i++) {
951		fp = *rp;
952		/*
953		 * zero the pointer before calling
954		 * unp_discard since it may end up
955		 * in unp_gc()..
956		 */
957		*rp++ = 0;
958		unp_discard(fp);
959	}
960}
961
962int
963unp_externalize(control, controlp)
964	struct mbuf *control, **controlp;
965{
966	struct thread *td = curthread;		/* XXX */
967	struct cmsghdr *cm = mtod(control, struct cmsghdr *);
968	int i;
969	int *fdp;
970	struct file **rp;
971	struct file *fp;
972	void *data;
973	socklen_t clen = control->m_len, datalen;
974	int error, newfds;
975	int f;
976	u_int newlen;
977
978	error = 0;
979	if (controlp != NULL) /* controlp == NULL => free control messages */
980		*controlp = NULL;
981
982	while (cm != NULL) {
983		if (sizeof(*cm) > clen || cm->cmsg_len > clen) {
984			error = EINVAL;
985			break;
986		}
987
988		data = CMSG_DATA(cm);
989		datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data;
990
991		if (cm->cmsg_level == SOL_SOCKET
992		    && cm->cmsg_type == SCM_RIGHTS) {
993			newfds = datalen / sizeof(struct file *);
994			rp = data;
995
996			/* If we're not outputting the discriptors free them. */
997			if (error || controlp == NULL) {
998				unp_freerights(rp, newfds);
999				goto next;
1000			}
1001			FILEDESC_LOCK(td->td_proc->p_fd);
1002			/* if the new FD's will not fit free them.  */
1003			if (!fdavail(td, newfds)) {
1004				FILEDESC_UNLOCK(td->td_proc->p_fd);
1005				error = EMSGSIZE;
1006				unp_freerights(rp, newfds);
1007				goto next;
1008			}
1009			/*
1010			 * now change each pointer to an fd in the global
1011			 * table to an integer that is the index to the
1012			 * local fd table entry that we set up to point
1013			 * to the global one we are transferring.
1014			 */
1015			newlen = newfds * sizeof(int);
1016			*controlp = sbcreatecontrol(NULL, newlen,
1017			    SCM_RIGHTS, SOL_SOCKET);
1018			if (*controlp == NULL) {
1019				FILEDESC_UNLOCK(td->td_proc->p_fd);
1020				error = E2BIG;
1021				unp_freerights(rp, newfds);
1022				goto next;
1023			}
1024
1025			fdp = (int *)
1026			    CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1027			for (i = 0; i < newfds; i++) {
1028				if (fdalloc(td, 0, &f))
1029					panic("unp_externalize fdalloc failed");
1030				fp = *rp++;
1031				td->td_proc->p_fd->fd_ofiles[f] = fp;
1032				FILE_LOCK(fp);
1033				fp->f_msgcount--;
1034				FILE_UNLOCK(fp);
1035				unp_rights--;
1036				*fdp++ = f;
1037			}
1038			FILEDESC_UNLOCK(td->td_proc->p_fd);
1039		} else { /* We can just copy anything else across */
1040			if (error || controlp == NULL)
1041				goto next;
1042			*controlp = sbcreatecontrol(NULL, datalen,
1043			    cm->cmsg_type, cm->cmsg_level);
1044			if (*controlp == NULL) {
1045				error = ENOBUFS;
1046				goto next;
1047			}
1048			bcopy(data,
1049			    CMSG_DATA(mtod(*controlp, struct cmsghdr *)),
1050			    datalen);
1051		}
1052
1053		controlp = &(*controlp)->m_next;
1054
1055next:
1056		if (CMSG_SPACE(datalen) < clen) {
1057			clen -= CMSG_SPACE(datalen);
1058			cm = (struct cmsghdr *)
1059			    ((caddr_t)cm + CMSG_SPACE(datalen));
1060		} else {
1061			clen = 0;
1062			cm = NULL;
1063		}
1064	}
1065
1066	m_freem(control);
1067
1068	return (error);
1069}
1070
1071void
1072unp_init(void)
1073{
1074	unp_zone = uma_zcreate("unpcb", sizeof(struct unpcb), NULL, NULL,
1075	    NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
1076	uma_zone_set_max(unp_zone, nmbclusters);
1077	if (unp_zone == 0)
1078		panic("unp_init");
1079	LIST_INIT(&unp_dhead);
1080	LIST_INIT(&unp_shead);
1081}
1082
1083#ifndef MIN
1084#define	MIN(a,b) (((a)<(b))?(a):(b))
1085#endif
1086
1087static int
1088unp_internalize(controlp, td)
1089	struct mbuf **controlp;
1090	struct thread *td;
1091{
1092	struct mbuf *control = *controlp;
1093	struct proc *p = td->td_proc;
1094	struct filedesc *fdescp = p->p_fd;
1095	struct cmsghdr *cm = mtod(control, struct cmsghdr *);
1096	struct cmsgcred *cmcred;
1097	struct file **rp;
1098	struct file *fp;
1099	struct timeval *tv;
1100	int i, fd, *fdp;
1101	void *data;
1102	socklen_t clen = control->m_len, datalen;
1103	int error, oldfds;
1104	u_int newlen;
1105
1106	error = 0;
1107	*controlp = NULL;
1108
1109	while (cm != NULL) {
1110		if (sizeof(*cm) > clen || cm->cmsg_level != SOL_SOCKET
1111		    || cm->cmsg_len > clen) {
1112			error = EINVAL;
1113			goto out;
1114		}
1115
1116		data = CMSG_DATA(cm);
1117		datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data;
1118
1119		switch (cm->cmsg_type) {
1120		/*
1121		 * Fill in credential information.
1122		 */
1123		case SCM_CREDS:
1124			*controlp = sbcreatecontrol(NULL, sizeof(*cmcred),
1125			    SCM_CREDS, SOL_SOCKET);
1126			if (*controlp == NULL) {
1127				error = ENOBUFS;
1128				goto out;
1129			}
1130
1131			cmcred = (struct cmsgcred *)
1132			    CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1133			cmcred->cmcred_pid = p->p_pid;
1134			cmcred->cmcred_uid = td->td_ucred->cr_ruid;
1135			cmcred->cmcred_gid = td->td_ucred->cr_rgid;
1136			cmcred->cmcred_euid = td->td_ucred->cr_uid;
1137			cmcred->cmcred_ngroups = MIN(td->td_ucred->cr_ngroups,
1138							CMGROUP_MAX);
1139			for (i = 0; i < cmcred->cmcred_ngroups; i++)
1140				cmcred->cmcred_groups[i] =
1141				    td->td_ucred->cr_groups[i];
1142			break;
1143
1144		case SCM_RIGHTS:
1145			oldfds = datalen / sizeof (int);
1146			/*
1147			 * check that all the FDs passed in refer to legal files
1148			 * If not, reject the entire operation.
1149			 */
1150			fdp = data;
1151			FILEDESC_LOCK(fdescp);
1152			for (i = 0; i < oldfds; i++) {
1153				fd = *fdp++;
1154				if ((unsigned)fd >= fdescp->fd_nfiles ||
1155				    fdescp->fd_ofiles[fd] == NULL) {
1156					FILEDESC_UNLOCK(fdescp);
1157					error = EBADF;
1158					goto out;
1159				}
1160			}
1161			/*
1162			 * Now replace the integer FDs with pointers to
1163			 * the associated global file table entry..
1164			 */
1165			newlen = oldfds * sizeof(struct file *);
1166			*controlp = sbcreatecontrol(NULL, newlen,
1167			    SCM_RIGHTS, SOL_SOCKET);
1168			if (*controlp == NULL) {
1169				FILEDESC_UNLOCK(fdescp);
1170				error = E2BIG;
1171				goto out;
1172			}
1173
1174			fdp = data;
1175			rp = (struct file **)
1176			    CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1177			for (i = 0; i < oldfds; i++) {
1178				fp = fdescp->fd_ofiles[*fdp++];
1179				*rp++ = fp;
1180				FILE_LOCK(fp);
1181				fp->f_count++;
1182				fp->f_msgcount++;
1183				FILE_UNLOCK(fp);
1184				unp_rights++;
1185			}
1186			FILEDESC_UNLOCK(fdescp);
1187			break;
1188
1189		case SCM_TIMESTAMP:
1190			*controlp = sbcreatecontrol(NULL, sizeof(*tv),
1191			    SCM_TIMESTAMP, SOL_SOCKET);
1192			if (*controlp == NULL) {
1193				error = ENOBUFS;
1194				goto out;
1195			}
1196			tv = (struct timeval *)
1197			    CMSG_DATA(mtod(*controlp, struct cmsghdr *));
1198			microtime(tv);
1199			break;
1200
1201		default:
1202			error = EINVAL;
1203			goto out;
1204		}
1205
1206		controlp = &(*controlp)->m_next;
1207
1208		if (CMSG_SPACE(datalen) < clen) {
1209			clen -= CMSG_SPACE(datalen);
1210			cm = (struct cmsghdr *)
1211			    ((caddr_t)cm + CMSG_SPACE(datalen));
1212		} else {
1213			clen = 0;
1214			cm = NULL;
1215		}
1216	}
1217
1218out:
1219	m_freem(control);
1220
1221	return (error);
1222}
1223
1224static int	unp_defer, unp_gcing;
1225
1226static void
1227unp_gc()
1228{
1229	register struct file *fp, *nextfp;
1230	register struct socket *so;
1231	struct file **extra_ref, **fpp;
1232	int nunref, i;
1233
1234	if (unp_gcing)
1235		return;
1236	unp_gcing = 1;
1237	unp_defer = 0;
1238	/*
1239	 * before going through all this, set all FDs to
1240	 * be NOT defered and NOT externally accessible
1241	 */
1242	sx_slock(&filelist_lock);
1243	LIST_FOREACH(fp, &filehead, f_list)
1244		fp->f_gcflag &= ~(FMARK|FDEFER);
1245	do {
1246		LIST_FOREACH(fp, &filehead, f_list) {
1247			FILE_LOCK(fp);
1248			/*
1249			 * If the file is not open, skip it
1250			 */
1251			if (fp->f_count == 0) {
1252				FILE_UNLOCK(fp);
1253				continue;
1254			}
1255			/*
1256			 * If we already marked it as 'defer'  in a
1257			 * previous pass, then try process it this time
1258			 * and un-mark it
1259			 */
1260			if (fp->f_gcflag & FDEFER) {
1261				fp->f_gcflag &= ~FDEFER;
1262				unp_defer--;
1263			} else {
1264				/*
1265				 * if it's not defered, then check if it's
1266				 * already marked.. if so skip it
1267				 */
1268				if (fp->f_gcflag & FMARK) {
1269					FILE_UNLOCK(fp);
1270					continue;
1271				}
1272				/*
1273				 * If all references are from messages
1274				 * in transit, then skip it. it's not
1275				 * externally accessible.
1276				 */
1277				if (fp->f_count == fp->f_msgcount) {
1278					FILE_UNLOCK(fp);
1279					continue;
1280				}
1281				/*
1282				 * If it got this far then it must be
1283				 * externally accessible.
1284				 */
1285				fp->f_gcflag |= FMARK;
1286			}
1287			/*
1288			 * either it was defered, or it is externally
1289			 * accessible and not already marked so.
1290			 * Now check if it is possibly one of OUR sockets.
1291			 */
1292			if (fp->f_type != DTYPE_SOCKET ||
1293			    (so = (struct socket *)fp->f_data) == 0) {
1294				FILE_UNLOCK(fp);
1295				continue;
1296			}
1297			FILE_UNLOCK(fp);
1298			if (so->so_proto->pr_domain != &localdomain ||
1299			    (so->so_proto->pr_flags&PR_RIGHTS) == 0)
1300				continue;
1301#ifdef notdef
1302			if (so->so_rcv.sb_flags & SB_LOCK) {
1303				/*
1304				 * This is problematical; it's not clear
1305				 * we need to wait for the sockbuf to be
1306				 * unlocked (on a uniprocessor, at least),
1307				 * and it's also not clear what to do
1308				 * if sbwait returns an error due to receipt
1309				 * of a signal.  If sbwait does return
1310				 * an error, we'll go into an infinite
1311				 * loop.  Delete all of this for now.
1312				 */
1313				(void) sbwait(&so->so_rcv);
1314				goto restart;
1315			}
1316#endif
1317			/*
1318			 * So, Ok, it's one of our sockets and it IS externally
1319			 * accessible (or was defered). Now we look
1320			 * to see if we hold any file descriptors in its
1321			 * message buffers. Follow those links and mark them
1322			 * as accessible too.
1323			 */
1324			unp_scan(so->so_rcv.sb_mb, unp_mark);
1325		}
1326	} while (unp_defer);
1327	sx_sunlock(&filelist_lock);
1328	/*
1329	 * We grab an extra reference to each of the file table entries
1330	 * that are not otherwise accessible and then free the rights
1331	 * that are stored in messages on them.
1332	 *
1333	 * The bug in the orginal code is a little tricky, so I'll describe
1334	 * what's wrong with it here.
1335	 *
1336	 * It is incorrect to simply unp_discard each entry for f_msgcount
1337	 * times -- consider the case of sockets A and B that contain
1338	 * references to each other.  On a last close of some other socket,
1339	 * we trigger a gc since the number of outstanding rights (unp_rights)
1340	 * is non-zero.  If during the sweep phase the gc code un_discards,
1341	 * we end up doing a (full) closef on the descriptor.  A closef on A
1342	 * results in the following chain.  Closef calls soo_close, which
1343	 * calls soclose.   Soclose calls first (through the switch
1344	 * uipc_usrreq) unp_detach, which re-invokes unp_gc.  Unp_gc simply
1345	 * returns because the previous instance had set unp_gcing, and
1346	 * we return all the way back to soclose, which marks the socket
1347	 * with SS_NOFDREF, and then calls sofree.  Sofree calls sorflush
1348	 * to free up the rights that are queued in messages on the socket A,
1349	 * i.e., the reference on B.  The sorflush calls via the dom_dispose
1350	 * switch unp_dispose, which unp_scans with unp_discard.  This second
1351	 * instance of unp_discard just calls closef on B.
1352	 *
1353	 * Well, a similar chain occurs on B, resulting in a sorflush on B,
1354	 * which results in another closef on A.  Unfortunately, A is already
1355	 * being closed, and the descriptor has already been marked with
1356	 * SS_NOFDREF, and soclose panics at this point.
1357	 *
1358	 * Here, we first take an extra reference to each inaccessible
1359	 * descriptor.  Then, we call sorflush ourself, since we know
1360	 * it is a Unix domain socket anyhow.  After we destroy all the
1361	 * rights carried in messages, we do a last closef to get rid
1362	 * of our extra reference.  This is the last close, and the
1363	 * unp_detach etc will shut down the socket.
1364	 *
1365	 * 91/09/19, bsy@cs.cmu.edu
1366	 */
1367	extra_ref = malloc(nfiles * sizeof(struct file *), M_TEMP, M_WAITOK);
1368	sx_slock(&filelist_lock);
1369	for (nunref = 0, fp = LIST_FIRST(&filehead), fpp = extra_ref; fp != 0;
1370	    fp = nextfp) {
1371		nextfp = LIST_NEXT(fp, f_list);
1372		FILE_LOCK(fp);
1373		/*
1374		 * If it's not open, skip it
1375		 */
1376		if (fp->f_count == 0) {
1377			FILE_UNLOCK(fp);
1378			continue;
1379		}
1380		/*
1381		 * If all refs are from msgs, and it's not marked accessible
1382		 * then it must be referenced from some unreachable cycle
1383		 * of (shut-down) FDs, so include it in our
1384		 * list of FDs to remove
1385		 */
1386		if (fp->f_count == fp->f_msgcount && !(fp->f_gcflag & FMARK)) {
1387			*fpp++ = fp;
1388			nunref++;
1389			fp->f_count++;
1390		}
1391		FILE_UNLOCK(fp);
1392	}
1393	sx_sunlock(&filelist_lock);
1394	/*
1395	 * for each FD on our hit list, do the following two things
1396	 */
1397	for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp) {
1398		struct file *tfp = *fpp;
1399		FILE_LOCK(tfp);
1400		if (tfp->f_type == DTYPE_SOCKET && tfp->f_data != NULL) {
1401			FILE_UNLOCK(tfp);
1402			sorflush((struct socket *)(tfp->f_data));
1403		} else
1404			FILE_UNLOCK(tfp);
1405	}
1406	for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp)
1407		closef(*fpp, (struct thread *) NULL);
1408	free((caddr_t)extra_ref, M_TEMP);
1409	unp_gcing = 0;
1410}
1411
1412void
1413unp_dispose(m)
1414	struct mbuf *m;
1415{
1416
1417	if (m)
1418		unp_scan(m, unp_discard);
1419}
1420
1421static int
1422unp_listen(unp, td)
1423	struct unpcb *unp;
1424	struct thread *td;
1425{
1426
1427	cru2x(td->td_ucred, &unp->unp_peercred);
1428	unp->unp_flags |= UNP_HAVEPCCACHED;
1429	return (0);
1430}
1431
1432static void
1433unp_scan(m0, op)
1434	register struct mbuf *m0;
1435	void (*op)(struct file *);
1436{
1437	struct mbuf *m;
1438	struct file **rp;
1439	struct cmsghdr *cm;
1440	void *data;
1441	int i;
1442	socklen_t clen, datalen;
1443	int qfds;
1444
1445	while (m0) {
1446		for (m = m0; m; m = m->m_next) {
1447			if (m->m_type != MT_CONTROL)
1448				continue;
1449
1450			cm = mtod(m, struct cmsghdr *);
1451			clen = m->m_len;
1452
1453			while (cm != NULL) {
1454				if (sizeof(*cm) > clen || cm->cmsg_len > clen)
1455					break;
1456
1457				data = CMSG_DATA(cm);
1458				datalen = (caddr_t)cm + cm->cmsg_len
1459				    - (caddr_t)data;
1460
1461				if (cm->cmsg_level == SOL_SOCKET &&
1462				    cm->cmsg_type == SCM_RIGHTS) {
1463					qfds = datalen / sizeof (struct file *);
1464					rp = data;
1465					for (i = 0; i < qfds; i++)
1466						(*op)(*rp++);
1467				}
1468
1469				if (CMSG_SPACE(datalen) < clen) {
1470					clen -= CMSG_SPACE(datalen);
1471					cm = (struct cmsghdr *)
1472					    ((caddr_t)cm + CMSG_SPACE(datalen));
1473				} else {
1474					clen = 0;
1475					cm = NULL;
1476				}
1477			}
1478		}
1479		m0 = m0->m_act;
1480	}
1481}
1482
1483static void
1484unp_mark(fp)
1485	struct file *fp;
1486{
1487	if (fp->f_gcflag & FMARK)
1488		return;
1489	unp_defer++;
1490	fp->f_gcflag |= (FMARK|FDEFER);
1491}
1492
1493static void
1494unp_discard(fp)
1495	struct file *fp;
1496{
1497	FILE_LOCK(fp);
1498	fp->f_msgcount--;
1499	unp_rights--;
1500	FILE_UNLOCK(fp);
1501	(void) closef(fp, (struct thread *)NULL);
1502}
1503