1 /*
2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * %sccs.include.redist.c%
6 *
7 * @(#)uipc_usrreq.c 8.9 (Berkeley) 05/14/95
8 */
9
10 #include <sys/param.h>
11 #include <sys/systm.h>
12 #include <sys/proc.h>
13 #include <sys/filedesc.h>
14 #include <sys/domain.h>
15 #include <sys/protosw.h>
16 #include <sys/socket.h>
17 #include <sys/socketvar.h>
18 #include <sys/unpcb.h>
19 #include <sys/un.h>
20 #include <sys/namei.h>
21 #include <sys/vnode.h>
22 #include <sys/file.h>
23 #include <sys/stat.h>
24 #include <sys/mbuf.h>
25
26 /*
27 * Unix communications domain.
28 *
29 * TODO:
30 * SEQPACKET, RDM
31 * rethink name space problems
32 * need a proper out-of-band
33 */
34 struct sockaddr sun_noname = { sizeof(sun_noname), AF_UNIX };
35 ino_t unp_ino; /* prototype for fake inode numbers */
36
37 /*ARGSUSED*/
38 int
uipc_usrreq(so,req,m,nam,control)39 uipc_usrreq(so, req, m, nam, control)
40 struct socket *so;
41 int req;
42 struct mbuf *m, *nam, *control;
43 {
44 struct unpcb *unp = sotounpcb(so);
45 register struct socket *so2;
46 register int error = 0;
47 struct proc *p = curproc; /* XXX */
48
49 if (req == PRU_CONTROL)
50 return (EOPNOTSUPP);
51 if (req != PRU_SEND && control && control->m_len) {
52 error = EOPNOTSUPP;
53 goto release;
54 }
55 if (unp == 0 && req != PRU_ATTACH) {
56 error = EINVAL;
57 goto release;
58 }
59 switch (req) {
60
61 case PRU_ATTACH:
62 if (unp) {
63 error = EISCONN;
64 break;
65 }
66 error = unp_attach(so);
67 break;
68
69 case PRU_DETACH:
70 unp_detach(unp);
71 break;
72
73 case PRU_BIND:
74 error = unp_bind(unp, nam, p);
75 break;
76
77 case PRU_LISTEN:
78 if (unp->unp_vnode == 0)
79 error = EINVAL;
80 break;
81
82 case PRU_CONNECT:
83 error = unp_connect(so, nam, p);
84 break;
85
86 case PRU_CONNECT2:
87 error = unp_connect2(so, (struct socket *)nam);
88 break;
89
90 case PRU_DISCONNECT:
91 unp_disconnect(unp);
92 break;
93
94 case PRU_ACCEPT:
95 /*
96 * Pass back name of connected socket,
97 * if it was bound and we are still connected
98 * (our peer may have closed already!).
99 */
100 if (unp->unp_conn && unp->unp_conn->unp_addr) {
101 nam->m_len = unp->unp_conn->unp_addr->m_len;
102 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t),
103 mtod(nam, caddr_t), (unsigned)nam->m_len);
104 } else {
105 nam->m_len = sizeof(sun_noname);
106 *(mtod(nam, struct sockaddr *)) = sun_noname;
107 }
108 break;
109
110 case PRU_SHUTDOWN:
111 socantsendmore(so);
112 unp_shutdown(unp);
113 break;
114
115 case PRU_RCVD:
116 switch (so->so_type) {
117
118 case SOCK_DGRAM:
119 panic("uipc 1");
120 /*NOTREACHED*/
121
122 case SOCK_STREAM:
123 #define rcv (&so->so_rcv)
124 #define snd (&so2->so_snd)
125 if (unp->unp_conn == 0)
126 break;
127 so2 = unp->unp_conn->unp_socket;
128 /*
129 * Adjust backpressure on sender
130 * and wakeup any waiting to write.
131 */
132 snd->sb_mbmax += unp->unp_mbcnt - rcv->sb_mbcnt;
133 unp->unp_mbcnt = rcv->sb_mbcnt;
134 snd->sb_hiwat += unp->unp_cc - rcv->sb_cc;
135 unp->unp_cc = rcv->sb_cc;
136 sowwakeup(so2);
137 #undef snd
138 #undef rcv
139 break;
140
141 default:
142 panic("uipc 2");
143 }
144 break;
145
146 case PRU_SEND:
147 if (control && (error = unp_internalize(control, p)))
148 break;
149 switch (so->so_type) {
150
151 case SOCK_DGRAM: {
152 struct sockaddr *from;
153
154 if (nam) {
155 if (unp->unp_conn) {
156 error = EISCONN;
157 break;
158 }
159 error = unp_connect(so, nam, p);
160 if (error)
161 break;
162 } else {
163 if (unp->unp_conn == 0) {
164 error = ENOTCONN;
165 break;
166 }
167 }
168 so2 = unp->unp_conn->unp_socket;
169 if (unp->unp_addr)
170 from = mtod(unp->unp_addr, struct sockaddr *);
171 else
172 from = &sun_noname;
173 if (sbappendaddr(&so2->so_rcv, from, m, control)) {
174 sorwakeup(so2);
175 m = 0;
176 control = 0;
177 } else
178 error = ENOBUFS;
179 if (nam)
180 unp_disconnect(unp);
181 break;
182 }
183
184 case SOCK_STREAM:
185 #define rcv (&so2->so_rcv)
186 #define snd (&so->so_snd)
187 if (so->so_state & SS_CANTSENDMORE) {
188 error = EPIPE;
189 break;
190 }
191 if (unp->unp_conn == 0)
192 panic("uipc 3");
193 so2 = unp->unp_conn->unp_socket;
194 /*
195 * Send to paired receive port, and then reduce
196 * send buffer hiwater marks to maintain backpressure.
197 * Wake up readers.
198 */
199 if (control) {
200 if (sbappendcontrol(rcv, m, control))
201 control = 0;
202 } else
203 sbappend(rcv, m);
204 snd->sb_mbmax -=
205 rcv->sb_mbcnt - unp->unp_conn->unp_mbcnt;
206 unp->unp_conn->unp_mbcnt = rcv->sb_mbcnt;
207 snd->sb_hiwat -= rcv->sb_cc - unp->unp_conn->unp_cc;
208 unp->unp_conn->unp_cc = rcv->sb_cc;
209 sorwakeup(so2);
210 m = 0;
211 #undef snd
212 #undef rcv
213 break;
214
215 default:
216 panic("uipc 4");
217 }
218 break;
219
220 case PRU_ABORT:
221 unp_drop(unp, ECONNABORTED);
222 break;
223
224 case PRU_SENSE:
225 ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat;
226 if (so->so_type == SOCK_STREAM && unp->unp_conn != 0) {
227 so2 = unp->unp_conn->unp_socket;
228 ((struct stat *) m)->st_blksize += so2->so_rcv.sb_cc;
229 }
230 ((struct stat *) m)->st_dev = NODEV;
231 if (unp->unp_ino == 0)
232 unp->unp_ino = unp_ino++;
233 ((struct stat *) m)->st_ino = unp->unp_ino;
234 return (0);
235
236 case PRU_RCVOOB:
237 return (EOPNOTSUPP);
238
239 case PRU_SENDOOB:
240 error = EOPNOTSUPP;
241 break;
242
243 case PRU_SOCKADDR:
244 if (unp->unp_addr) {
245 nam->m_len = unp->unp_addr->m_len;
246 bcopy(mtod(unp->unp_addr, caddr_t),
247 mtod(nam, caddr_t), (unsigned)nam->m_len);
248 } else
249 nam->m_len = 0;
250 break;
251
252 case PRU_PEERADDR:
253 if (unp->unp_conn && unp->unp_conn->unp_addr) {
254 nam->m_len = unp->unp_conn->unp_addr->m_len;
255 bcopy(mtod(unp->unp_conn->unp_addr, caddr_t),
256 mtod(nam, caddr_t), (unsigned)nam->m_len);
257 } else
258 nam->m_len = 0;
259 break;
260
261 case PRU_SLOWTIMO:
262 break;
263
264 default:
265 panic("piusrreq");
266 }
267 release:
268 if (control)
269 m_freem(control);
270 if (m)
271 m_freem(m);
272 return (error);
273 }
274
275 /*
276 * Both send and receive buffers are allocated PIPSIZ bytes of buffering
277 * for stream sockets, although the total for sender and receiver is
278 * actually only PIPSIZ.
279 * Datagram sockets really use the sendspace as the maximum datagram size,
280 * and don't really want to reserve the sendspace. Their recvspace should
281 * be large enough for at least one max-size datagram plus address.
282 */
283 #define PIPSIZ 4096
284 u_long unpst_sendspace = PIPSIZ;
285 u_long unpst_recvspace = PIPSIZ;
286 u_long unpdg_sendspace = 2*1024; /* really max datagram size */
287 u_long unpdg_recvspace = 4*1024;
288
289 int unp_rights; /* file descriptors in flight */
290
291 int
unp_attach(so)292 unp_attach(so)
293 struct socket *so;
294 {
295 register struct mbuf *m;
296 register struct unpcb *unp;
297 int error;
298
299 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
300 switch (so->so_type) {
301
302 case SOCK_STREAM:
303 error = soreserve(so, unpst_sendspace, unpst_recvspace);
304 break;
305
306 case SOCK_DGRAM:
307 error = soreserve(so, unpdg_sendspace, unpdg_recvspace);
308 break;
309
310 default:
311 panic("unp_attach");
312 }
313 if (error)
314 return (error);
315 }
316 m = m_getclr(M_DONTWAIT, MT_PCB);
317 if (m == NULL)
318 return (ENOBUFS);
319 unp = mtod(m, struct unpcb *);
320 so->so_pcb = (caddr_t)unp;
321 unp->unp_socket = so;
322 return (0);
323 }
324
325 void
unp_detach(unp)326 unp_detach(unp)
327 register struct unpcb *unp;
328 {
329
330 if (unp->unp_vnode) {
331 unp->unp_vnode->v_socket = 0;
332 vrele(unp->unp_vnode);
333 unp->unp_vnode = 0;
334 }
335 if (unp->unp_conn)
336 unp_disconnect(unp);
337 while (unp->unp_refs)
338 unp_drop(unp->unp_refs, ECONNRESET);
339 soisdisconnected(unp->unp_socket);
340 unp->unp_socket->so_pcb = 0;
341 m_freem(unp->unp_addr);
342 (void) m_free(dtom(unp));
343 if (unp_rights) {
344 /*
345 * Normally the receive buffer is flushed later,
346 * in sofree, but if our receive buffer holds references
347 * to descriptors that are now garbage, we will dispose
348 * of those descriptor references after the garbage collector
349 * gets them (resulting in a "panic: closef: count < 0").
350 */
351 sorflush(unp->unp_socket);
352 unp_gc();
353 }
354 }
355
356 int
unp_bind(unp,nam,p)357 unp_bind(unp, nam, p)
358 struct unpcb *unp;
359 struct mbuf *nam;
360 struct proc *p;
361 {
362 struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *);
363 register struct vnode *vp;
364 struct vattr vattr;
365 int error;
366 struct nameidata nd;
367
368 NDINIT(&nd, CREATE, FOLLOW | LOCKPARENT, UIO_SYSSPACE,
369 soun->sun_path, p);
370 if (unp->unp_vnode != NULL)
371 return (EINVAL);
372 if (nam->m_len == MLEN) {
373 if (*(mtod(nam, caddr_t) + nam->m_len - 1) != 0)
374 return (EINVAL);
375 } else
376 *(mtod(nam, caddr_t) + nam->m_len) = 0;
377 /* SHOULD BE ABLE TO ADOPT EXISTING AND wakeup() ALA FIFO's */
378 if (error = namei(&nd))
379 return (error);
380 vp = nd.ni_vp;
381 if (vp != NULL) {
382 VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
383 if (nd.ni_dvp == vp)
384 vrele(nd.ni_dvp);
385 else
386 vput(nd.ni_dvp);
387 vrele(vp);
388 return (EADDRINUSE);
389 }
390 VATTR_NULL(&vattr);
391 vattr.va_type = VSOCK;
392 vattr.va_mode = ACCESSPERMS;
393 VOP_LEASE(nd.ni_dvp, p, p->p_ucred, LEASE_WRITE);
394 if (error = VOP_CREATE(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr))
395 return (error);
396 vp = nd.ni_vp;
397 vp->v_socket = unp->unp_socket;
398 unp->unp_vnode = vp;
399 unp->unp_addr = m_copy(nam, 0, (int)M_COPYALL);
400 VOP_UNLOCK(vp, 0, p);
401 return (0);
402 }
403
404 int
unp_connect(so,nam,p)405 unp_connect(so, nam, p)
406 struct socket *so;
407 struct mbuf *nam;
408 struct proc *p;
409 {
410 register struct sockaddr_un *soun = mtod(nam, struct sockaddr_un *);
411 register struct vnode *vp;
412 register struct socket *so2, *so3;
413 struct unpcb *unp2, *unp3;
414 int error;
415 struct nameidata nd;
416
417 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, soun->sun_path, p);
418 if (nam->m_data + nam->m_len == &nam->m_dat[MLEN]) { /* XXX */
419 if (*(mtod(nam, caddr_t) + nam->m_len - 1) != 0)
420 return (EMSGSIZE);
421 } else
422 *(mtod(nam, caddr_t) + nam->m_len) = 0;
423 if (error = namei(&nd))
424 return (error);
425 vp = nd.ni_vp;
426 if (vp->v_type != VSOCK) {
427 error = ENOTSOCK;
428 goto bad;
429 }
430 if (error = VOP_ACCESS(vp, VWRITE, p->p_ucred, p))
431 goto bad;
432 so2 = vp->v_socket;
433 if (so2 == 0) {
434 error = ECONNREFUSED;
435 goto bad;
436 }
437 if (so->so_type != so2->so_type) {
438 error = EPROTOTYPE;
439 goto bad;
440 }
441 if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
442 if ((so2->so_options & SO_ACCEPTCONN) == 0 ||
443 (so3 = sonewconn(so2, 0)) == 0) {
444 error = ECONNREFUSED;
445 goto bad;
446 }
447 unp2 = sotounpcb(so2);
448 unp3 = sotounpcb(so3);
449 if (unp2->unp_addr)
450 unp3->unp_addr =
451 m_copy(unp2->unp_addr, 0, (int)M_COPYALL);
452 so2 = so3;
453 }
454 error = unp_connect2(so, so2);
455 bad:
456 vput(vp);
457 return (error);
458 }
459
460 int
unp_connect2(so,so2)461 unp_connect2(so, so2)
462 register struct socket *so;
463 register struct socket *so2;
464 {
465 register struct unpcb *unp = sotounpcb(so);
466 register struct unpcb *unp2;
467
468 if (so2->so_type != so->so_type)
469 return (EPROTOTYPE);
470 unp2 = sotounpcb(so2);
471 unp->unp_conn = unp2;
472 switch (so->so_type) {
473
474 case SOCK_DGRAM:
475 unp->unp_nextref = unp2->unp_refs;
476 unp2->unp_refs = unp;
477 soisconnected(so);
478 break;
479
480 case SOCK_STREAM:
481 unp2->unp_conn = unp;
482 soisconnected(so);
483 soisconnected(so2);
484 break;
485
486 default:
487 panic("unp_connect2");
488 }
489 return (0);
490 }
491
492 void
unp_disconnect(unp)493 unp_disconnect(unp)
494 struct unpcb *unp;
495 {
496 register struct unpcb *unp2 = unp->unp_conn;
497
498 if (unp2 == 0)
499 return;
500 unp->unp_conn = 0;
501 switch (unp->unp_socket->so_type) {
502
503 case SOCK_DGRAM:
504 if (unp2->unp_refs == unp)
505 unp2->unp_refs = unp->unp_nextref;
506 else {
507 unp2 = unp2->unp_refs;
508 for (;;) {
509 if (unp2 == 0)
510 panic("unp_disconnect");
511 if (unp2->unp_nextref == unp)
512 break;
513 unp2 = unp2->unp_nextref;
514 }
515 unp2->unp_nextref = unp->unp_nextref;
516 }
517 unp->unp_nextref = 0;
518 unp->unp_socket->so_state &= ~SS_ISCONNECTED;
519 break;
520
521 case SOCK_STREAM:
522 soisdisconnected(unp->unp_socket);
523 unp2->unp_conn = 0;
524 soisdisconnected(unp2->unp_socket);
525 break;
526 }
527 }
528
529 #ifdef notdef
530 void
unp_abort(unp)531 unp_abort(unp)
532 struct unpcb *unp;
533 {
534
535 unp_detach(unp);
536 }
537 #endif
538
539 void
unp_shutdown(unp)540 unp_shutdown(unp)
541 struct unpcb *unp;
542 {
543 struct socket *so;
544
545 if (unp->unp_socket->so_type == SOCK_STREAM && unp->unp_conn &&
546 (so = unp->unp_conn->unp_socket))
547 socantrcvmore(so);
548 }
549
550 void
unp_drop(unp,errno)551 unp_drop(unp, errno)
552 struct unpcb *unp;
553 int errno;
554 {
555 struct socket *so = unp->unp_socket;
556
557 so->so_error = errno;
558 unp_disconnect(unp);
559 if (so->so_head) {
560 so->so_pcb = (caddr_t) 0;
561 m_freem(unp->unp_addr);
562 (void) m_free(dtom(unp));
563 sofree(so);
564 }
565 }
566
567 #ifdef notdef
unp_drain()568 unp_drain()
569 {
570
571 }
572 #endif
573
574 int
unp_externalize(rights)575 unp_externalize(rights)
576 struct mbuf *rights;
577 {
578 struct proc *p = curproc; /* XXX */
579 register int i;
580 register struct cmsghdr *cm = mtod(rights, struct cmsghdr *);
581 register struct file **rp = (struct file **)(cm + 1);
582 register struct file *fp;
583 int newfds = (cm->cmsg_len - sizeof(*cm)) / sizeof (int);
584 int f;
585
586 if (!fdavail(p, newfds)) {
587 for (i = 0; i < newfds; i++) {
588 fp = *rp;
589 unp_discard(fp);
590 *rp++ = 0;
591 }
592 return (EMSGSIZE);
593 }
594 for (i = 0; i < newfds; i++) {
595 if (fdalloc(p, 0, &f))
596 panic("unp_externalize");
597 fp = *rp;
598 p->p_fd->fd_ofiles[f] = fp;
599 fp->f_msgcount--;
600 unp_rights--;
601 *(int *)rp++ = f;
602 }
603 return (0);
604 }
605
606 int
unp_internalize(control,p)607 unp_internalize(control, p)
608 struct mbuf *control;
609 struct proc *p;
610 {
611 struct filedesc *fdp = p->p_fd;
612 register struct cmsghdr *cm = mtod(control, struct cmsghdr *);
613 register struct file **rp;
614 register struct file *fp;
615 register int i, fd;
616 int oldfds;
617
618 if (cm->cmsg_type != SCM_RIGHTS || cm->cmsg_level != SOL_SOCKET ||
619 cm->cmsg_len != control->m_len)
620 return (EINVAL);
621 oldfds = (cm->cmsg_len - sizeof (*cm)) / sizeof (int);
622 rp = (struct file **)(cm + 1);
623 for (i = 0; i < oldfds; i++) {
624 fd = *(int *)rp++;
625 if ((unsigned)fd >= fdp->fd_nfiles ||
626 fdp->fd_ofiles[fd] == NULL)
627 return (EBADF);
628 }
629 rp = (struct file **)(cm + 1);
630 for (i = 0; i < oldfds; i++) {
631 fp = fdp->fd_ofiles[*(int *)rp];
632 *rp++ = fp;
633 fp->f_count++;
634 fp->f_msgcount++;
635 unp_rights++;
636 }
637 return (0);
638 }
639
640 int unp_defer, unp_gcing;
641 extern struct domain unixdomain;
642
643 void
unp_gc()644 unp_gc()
645 {
646 register struct file *fp, *nextfp;
647 register struct socket *so;
648 struct file **extra_ref, **fpp;
649 int nunref, i;
650
651 if (unp_gcing)
652 return;
653 unp_gcing = 1;
654 unp_defer = 0;
655 for (fp = filehead.lh_first; fp != 0; fp = fp->f_list.le_next)
656 fp->f_flag &= ~(FMARK|FDEFER);
657 do {
658 for (fp = filehead.lh_first; fp != 0; fp = fp->f_list.le_next) {
659 if (fp->f_count == 0)
660 continue;
661 if (fp->f_flag & FDEFER) {
662 fp->f_flag &= ~FDEFER;
663 unp_defer--;
664 } else {
665 if (fp->f_flag & FMARK)
666 continue;
667 if (fp->f_count == fp->f_msgcount)
668 continue;
669 fp->f_flag |= FMARK;
670 }
671 if (fp->f_type != DTYPE_SOCKET ||
672 (so = (struct socket *)fp->f_data) == 0)
673 continue;
674 if (so->so_proto->pr_domain != &unixdomain ||
675 (so->so_proto->pr_flags&PR_RIGHTS) == 0)
676 continue;
677 #ifdef notdef
678 if (so->so_rcv.sb_flags & SB_LOCK) {
679 /*
680 * This is problematical; it's not clear
681 * we need to wait for the sockbuf to be
682 * unlocked (on a uniprocessor, at least),
683 * and it's also not clear what to do
684 * if sbwait returns an error due to receipt
685 * of a signal. If sbwait does return
686 * an error, we'll go into an infinite
687 * loop. Delete all of this for now.
688 */
689 (void) sbwait(&so->so_rcv);
690 goto restart;
691 }
692 #endif
693 unp_scan(so->so_rcv.sb_mb, unp_mark);
694 }
695 } while (unp_defer);
696 /*
697 * We grab an extra reference to each of the file table entries
698 * that are not otherwise accessible and then free the rights
699 * that are stored in messages on them.
700 *
701 * The bug in the orginal code is a little tricky, so I'll describe
702 * what's wrong with it here.
703 *
704 * It is incorrect to simply unp_discard each entry for f_msgcount
705 * times -- consider the case of sockets A and B that contain
706 * references to each other. On a last close of some other socket,
707 * we trigger a gc since the number of outstanding rights (unp_rights)
708 * is non-zero. If during the sweep phase the gc code un_discards,
709 * we end up doing a (full) closef on the descriptor. A closef on A
710 * results in the following chain. Closef calls soo_close, which
711 * calls soclose. Soclose calls first (through the switch
712 * uipc_usrreq) unp_detach, which re-invokes unp_gc. Unp_gc simply
713 * returns because the previous instance had set unp_gcing, and
714 * we return all the way back to soclose, which marks the socket
715 * with SS_NOFDREF, and then calls sofree. Sofree calls sorflush
716 * to free up the rights that are queued in messages on the socket A,
717 * i.e., the reference on B. The sorflush calls via the dom_dispose
718 * switch unp_dispose, which unp_scans with unp_discard. This second
719 * instance of unp_discard just calls closef on B.
720 *
721 * Well, a similar chain occurs on B, resulting in a sorflush on B,
722 * which results in another closef on A. Unfortunately, A is already
723 * being closed, and the descriptor has already been marked with
724 * SS_NOFDREF, and soclose panics at this point.
725 *
726 * Here, we first take an extra reference to each inaccessible
727 * descriptor. Then, we call sorflush ourself, since we know
728 * it is a Unix domain socket anyhow. After we destroy all the
729 * rights carried in messages, we do a last closef to get rid
730 * of our extra reference. This is the last close, and the
731 * unp_detach etc will shut down the socket.
732 *
733 * 91/09/19, bsy@cs.cmu.edu
734 */
735 extra_ref = malloc(nfiles * sizeof(struct file *), M_FILE, M_WAITOK);
736 for (nunref = 0, fp = filehead.lh_first, fpp = extra_ref; fp != 0;
737 fp = nextfp) {
738 nextfp = fp->f_list.le_next;
739 if (fp->f_count == 0)
740 continue;
741 if (fp->f_count == fp->f_msgcount && !(fp->f_flag & FMARK)) {
742 *fpp++ = fp;
743 nunref++;
744 fp->f_count++;
745 }
746 }
747 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp)
748 sorflush((struct socket *)(*fpp)->f_data);
749 for (i = nunref, fpp = extra_ref; --i >= 0; ++fpp)
750 closef(*fpp, (struct proc *)NULL);
751 free((caddr_t)extra_ref, M_FILE);
752 unp_gcing = 0;
753 }
754
755 void
unp_dispose(m)756 unp_dispose(m)
757 struct mbuf *m;
758 {
759
760 if (m)
761 unp_scan(m, unp_discard);
762 }
763
764 void
unp_scan(m0,op)765 unp_scan(m0, op)
766 register struct mbuf *m0;
767 void (*op) __P((struct file *));
768 {
769 register struct mbuf *m;
770 register struct file **rp;
771 register struct cmsghdr *cm;
772 register int i;
773 int qfds;
774
775 while (m0) {
776 for (m = m0; m; m = m->m_next)
777 if (m->m_type == MT_CONTROL &&
778 m->m_len >= sizeof(*cm)) {
779 cm = mtod(m, struct cmsghdr *);
780 if (cm->cmsg_level != SOL_SOCKET ||
781 cm->cmsg_type != SCM_RIGHTS)
782 continue;
783 qfds = (cm->cmsg_len - sizeof *cm)
784 / sizeof (struct file *);
785 rp = (struct file **)(cm + 1);
786 for (i = 0; i < qfds; i++)
787 (*op)(*rp++);
788 break; /* XXX, but saves time */
789 }
790 m0 = m0->m_act;
791 }
792 }
793
794 void
unp_mark(fp)795 unp_mark(fp)
796 struct file *fp;
797 {
798
799 if (fp->f_flag & FMARK)
800 return;
801 unp_defer++;
802 fp->f_flag |= (FMARK|FDEFER);
803 }
804
805 void
unp_discard(fp)806 unp_discard(fp)
807 struct file *fp;
808 {
809
810 fp->f_msgcount--;
811 unp_rights--;
812 (void) closef(fp, (struct proc *)NULL);
813 }
814