1 /*-
2 * Copyright (c) 2001 Dag-Erling Coïdan Smørgrav
3 * 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 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include "opt_pseudofs.h"
33
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/ctype.h>
38 #include <sys/dirent.h>
39 #include <sys/fcntl.h>
40 #include <sys/limits.h>
41 #include <sys/lock.h>
42 #include <sys/malloc.h>
43 #include <sys/mount.h>
44 #include <sys/mutex.h>
45 #include <sys/namei.h>
46 #include <sys/proc.h>
47 #include <sys/sbuf.h>
48 #include <sys/sx.h>
49 #include <sys/sysctl.h>
50 #include <sys/vnode.h>
51
52 #include <fs/pseudofs/pseudofs.h>
53 #include <fs/pseudofs/pseudofs_internal.h>
54
55 #define KASSERT_PN_IS_DIR(pn) \
56 KASSERT((pn)->pn_type == pfstype_root || \
57 (pn)->pn_type == pfstype_dir || \
58 (pn)->pn_type == pfstype_procdir, \
59 ("%s(): VDIR vnode refers to non-directory pfs_node", __func__))
60
61 #define KASSERT_PN_IS_FILE(pn) \
62 KASSERT((pn)->pn_type == pfstype_file, \
63 ("%s(): VREG vnode refers to non-file pfs_node", __func__))
64
65 #define KASSERT_PN_IS_LINK(pn) \
66 KASSERT((pn)->pn_type == pfstype_symlink, \
67 ("%s(): VLNK vnode refers to non-link pfs_node", __func__))
68
69 /*
70 * Returns the fileno, adjusted for target pid
71 */
72 static uint32_t
73 pn_fileno(struct pfs_node *pn, pid_t pid)
74 {
75
76 KASSERT(pn->pn_fileno > 0,
77 ("%s(): no fileno allocated", __func__));
78 if (pid != NO_PID)
79 return (pn->pn_fileno * NO_PID + pid);
80 return (pn->pn_fileno);
81 }
82
83 /*
84 * Returns non-zero if given file is visible to given thread.
85 */
86 static int
87 pfs_visible_proc(struct thread *td, struct pfs_node *pn, struct proc *proc)
88 {
89 int visible;
90
91 if (proc == NULL)
92 return (0);
93
94 PROC_LOCK_ASSERT(proc, MA_OWNED);
95
96 visible = ((proc->p_flag & P_WEXIT) == 0);
97 if (visible)
98 visible = (p_cansee(td, proc) == 0);
99 if (visible && pn->pn_vis != NULL)
100 visible = pn_vis(td, proc, pn);
101 if (!visible)
102 return (0);
103 return (1);
104 }
105
106 static int
107 pfs_visible(struct thread *td, struct pfs_node *pn, pid_t pid,
108 bool allproc_locked, struct proc **p)
109 {
110 struct proc *proc;
111
112 PFS_TRACE(("%s (pid: %d, req: %d)",
113 pn->pn_name, pid, td->td_proc->p_pid));
114
115 if (p)
116 *p = NULL;
117 if (pid == NO_PID)
118 PFS_RETURN (1);
119 proc = allproc_locked ? pfind_locked(pid) : pfind(pid);
120 if (proc == NULL)
121 PFS_RETURN (0);
122 if (pfs_visible_proc(td, pn, proc)) {
123 if (p)
124 *p = proc;
125 else
126 PROC_UNLOCK(proc);
127 PFS_RETURN (1);
128 }
129 PROC_UNLOCK(proc);
130 PFS_RETURN (0);
131 }
132
133 /*
134 * Verify permissions
135 */
136 static int
137 pfs_access(struct vop_access_args *va)
138 {
139 struct vnode *vn = va->a_vp;
140 struct pfs_vdata *pvd = vn->v_data;
141 struct vattr vattr;
142 int error;
143
144 PFS_TRACE(("%s", pvd->pvd_pn->pn_name));
145 (void)pvd;
146
147 error = VOP_GETATTR(vn, &vattr, va->a_cred);
148 if (error)
149 PFS_RETURN (error);
150 error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid,
151 vattr.va_gid, va->a_accmode, va->a_cred, NULL);
152 PFS_RETURN (error);
153 }
154
155 /*
156 * Close a file or directory
157 */
158 static int
159 pfs_close(struct vop_close_args *va)
160 {
161 struct vnode *vn = va->a_vp;
162 struct pfs_vdata *pvd = vn->v_data;
163 struct pfs_node *pn = pvd->pvd_pn;
164 struct proc *proc;
165 int error;
166
167 PFS_TRACE(("%s", pn->pn_name));
168 pfs_assert_not_owned(pn);
169
170 /*
171 * Do nothing unless this is the last close and the node has a
172 * last-close handler.
173 */
174 if (vrefcnt(vn) > 1 || pn->pn_close == NULL)
175 PFS_RETURN (0);
176
177 if (pvd->pvd_pid != NO_PID) {
178 proc = pfind(pvd->pvd_pid);
179 } else {
180 proc = NULL;
181 }
182
183 error = pn_close(va->a_td, proc, pn);
184
185 if (proc != NULL)
186 PROC_UNLOCK(proc);
187
188 PFS_RETURN (error);
189 }
190
191 /*
192 * Get file attributes
193 */
194 static int
195 pfs_getattr(struct vop_getattr_args *va)
196 {
197 struct vnode *vn = va->a_vp;
198 struct pfs_vdata *pvd = vn->v_data;
199 struct pfs_node *pn = pvd->pvd_pn;
200 struct vattr *vap = va->a_vap;
201 struct proc *proc;
202 int error = 0;
203
204 PFS_TRACE(("%s", pn->pn_name));
205 pfs_assert_not_owned(pn);
206
207 if (!pfs_visible(curthread, pn, pvd->pvd_pid, false, &proc))
208 PFS_RETURN (ENOENT);
209
210 vap->va_type = vn->v_type;
211 vap->va_fileid = pn_fileno(pn, pvd->pvd_pid);
212 vap->va_flags = 0;
213 vap->va_blocksize = PAGE_SIZE;
214 vap->va_bytes = vap->va_size = 0;
215 vap->va_filerev = 0;
216 vap->va_fsid = vn->v_mount->mnt_stat.f_fsid.val[0];
217 vap->va_nlink = 1;
218 nanotime(&vap->va_ctime);
219 vap->va_atime = vap->va_mtime = vap->va_ctime;
220
221 switch (pn->pn_type) {
222 case pfstype_procdir:
223 case pfstype_root:
224 case pfstype_dir:
225 #if 0
226 pfs_lock(pn);
227 /* compute link count */
228 pfs_unlock(pn);
229 #endif
230 vap->va_mode = 0555;
231 break;
232 case pfstype_file:
233 case pfstype_symlink:
234 vap->va_mode = 0444;
235 break;
236 default:
237 printf("shouldn't be here!\n");
238 vap->va_mode = 0;
239 break;
240 }
241
242 if (proc != NULL) {
243 vap->va_uid = proc->p_ucred->cr_ruid;
244 vap->va_gid = proc->p_ucred->cr_rgid;
245 } else {
246 vap->va_uid = 0;
247 vap->va_gid = 0;
248 }
249
250 if (pn->pn_attr != NULL)
251 error = pn_attr(curthread, proc, pn, vap);
252
253 if(proc != NULL)
254 PROC_UNLOCK(proc);
255
256 PFS_RETURN (error);
257 }
258
259 /*
260 * Perform an ioctl
261 */
262 static int
263 pfs_ioctl(struct vop_ioctl_args *va)
264 {
265 struct vnode *vn;
266 struct pfs_vdata *pvd;
267 struct pfs_node *pn;
268 struct proc *proc;
269 int error;
270
271 vn = va->a_vp;
272 vn_lock(vn, LK_SHARED | LK_RETRY);
273 if (vn->v_iflag & VI_DOOMED) {
274 VOP_UNLOCK(vn, 0);
275 return (EBADF);
276 }
277 pvd = vn->v_data;
278 pn = pvd->pvd_pn;
279
280 PFS_TRACE(("%s: %lx", pn->pn_name, va->a_command));
281 pfs_assert_not_owned(pn);
282
283 if (vn->v_type != VREG) {
284 VOP_UNLOCK(vn, 0);
285 PFS_RETURN (EINVAL);
286 }
287 KASSERT_PN_IS_FILE(pn);
288
289 if (pn->pn_ioctl == NULL) {
290 VOP_UNLOCK(vn, 0);
291 PFS_RETURN (ENOTTY);
292 }
293
294 /*
295 * This is necessary because process' privileges may
296 * have changed since the open() call.
297 */
298 if (!pfs_visible(curthread, pn, pvd->pvd_pid, false, &proc)) {
299 VOP_UNLOCK(vn, 0);
300 PFS_RETURN (EIO);
301 }
302
303 error = pn_ioctl(curthread, proc, pn, va->a_command, va->a_data);
304
305 if (proc != NULL)
306 PROC_UNLOCK(proc);
307
308 VOP_UNLOCK(vn, 0);
309 PFS_RETURN (error);
310 }
311
312 /*
313 * Perform getextattr
314 */
315 static int
316 pfs_getextattr(struct vop_getextattr_args *va)
317 {
318 struct vnode *vn = va->a_vp;
319 struct pfs_vdata *pvd = vn->v_data;
320 struct pfs_node *pn = pvd->pvd_pn;
321 struct proc *proc;
322 int error;
323
324 PFS_TRACE(("%s", pn->pn_name));
325 pfs_assert_not_owned(pn);
326
327 /*
328 * This is necessary because either process' privileges may
329 * have changed since the open() call.
330 */
331 if (!pfs_visible(curthread, pn, pvd->pvd_pid, false, &proc))
332 PFS_RETURN (EIO);
333
334 if (pn->pn_getextattr == NULL)
335 error = EOPNOTSUPP;
336 else
337 error = pn_getextattr(curthread, proc, pn,
338 va->a_attrnamespace, va->a_name, va->a_uio,
339 va->a_size, va->a_cred);
340
341 if (proc != NULL)
342 PROC_UNLOCK(proc);
343
344 PFS_RETURN (error);
345 }
346
347 /*
348 * Convert a vnode to its component name
349 */
350 static int
351 pfs_vptocnp(struct vop_vptocnp_args *ap)
352 {
353 struct vnode *vp = ap->a_vp;
354 struct vnode **dvp = ap->a_vpp;
355 struct pfs_vdata *pvd = vp->v_data;
356 struct pfs_node *pd = pvd->pvd_pn;
357 struct pfs_node *pn;
358 struct mount *mp;
359 char *buf = ap->a_buf;
360 int *buflen = ap->a_buflen;
361 char pidbuf[PFS_NAMELEN];
362 pid_t pid = pvd->pvd_pid;
363 int len, i, error, locked;
364
365 i = *buflen;
366 error = 0;
367
368 pfs_lock(pd);
369
370 if (vp->v_type == VDIR && pd->pn_type == pfstype_root) {
371 *dvp = vp;
372 vhold(*dvp);
373 pfs_unlock(pd);
374 PFS_RETURN (0);
375 } else if (vp->v_type == VDIR && pd->pn_type == pfstype_procdir) {
376 len = snprintf(pidbuf, sizeof(pidbuf), "%d", pid);
377 i -= len;
378 if (i < 0) {
379 error = ENOMEM;
380 goto failed;
381 }
382 bcopy(pidbuf, buf + i, len);
383 } else {
384 len = strlen(pd->pn_name);
385 i -= len;
386 if (i < 0) {
387 error = ENOMEM;
388 goto failed;
389 }
390 bcopy(pd->pn_name, buf + i, len);
391 }
392
393 pn = pd->pn_parent;
394 pfs_unlock(pd);
395
396 mp = vp->v_mount;
397 error = vfs_busy(mp, 0);
398 if (error)
399 return (error);
400
401 /*
402 * vp is held by caller.
403 */
404 locked = VOP_ISLOCKED(vp);
405 VOP_UNLOCK(vp, 0);
406
407 error = pfs_vncache_alloc(mp, dvp, pn, pid);
408 if (error) {
409 vn_lock(vp, locked | LK_RETRY);
410 vfs_unbusy(mp);
411 PFS_RETURN(error);
412 }
413
414 *buflen = i;
415 VOP_UNLOCK(*dvp, 0);
416 vn_lock(vp, locked | LK_RETRY);
417 vfs_unbusy(mp);
418
419 PFS_RETURN (0);
420 failed:
421 pfs_unlock(pd);
422 PFS_RETURN(error);
423 }
424
425 /*
426 * Look up a file or directory
427 */
428 static int
429 pfs_lookup(struct vop_cachedlookup_args *va)
430 {
431 struct vnode *vn = va->a_dvp;
432 struct vnode **vpp = va->a_vpp;
433 struct componentname *cnp = va->a_cnp;
434 struct pfs_vdata *pvd = vn->v_data;
435 struct pfs_node *pd = pvd->pvd_pn;
436 struct pfs_node *pn, *pdn = NULL;
437 struct mount *mp;
438 pid_t pid = pvd->pvd_pid;
439 char *pname;
440 int error, i, namelen, visible;
441
442 PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr));
443 pfs_assert_not_owned(pd);
444
445 if (vn->v_type != VDIR)
446 PFS_RETURN (ENOTDIR);
447 KASSERT_PN_IS_DIR(pd);
448
449 /*
450 * Don't support DELETE or RENAME. CREATE is supported so
451 * that O_CREAT will work, but the lookup will still fail if
452 * the file does not exist.
453 */
454 if ((cnp->cn_flags & ISLASTCN) &&
455 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
456 PFS_RETURN (EOPNOTSUPP);
457
458 /* shortcut: check if the name is too long */
459 if (cnp->cn_namelen >= PFS_NAMELEN)
460 PFS_RETURN (ENOENT);
461
462 /* check that parent directory is visible... */
463 if (!pfs_visible(curthread, pd, pvd->pvd_pid, false, NULL))
464 PFS_RETURN (ENOENT);
465
466 /* self */
467 namelen = cnp->cn_namelen;
468 pname = cnp->cn_nameptr;
469 if (namelen == 1 && pname[0] == '.') {
470 pn = pd;
471 *vpp = vn;
472 VREF(vn);
473 PFS_RETURN (0);
474 }
475
476 mp = vn->v_mount;
477
478 /* parent */
479 if (cnp->cn_flags & ISDOTDOT) {
480 if (pd->pn_type == pfstype_root)
481 PFS_RETURN (EIO);
482 error = vfs_busy(mp, MBF_NOWAIT);
483 if (error != 0) {
484 vfs_ref(mp);
485 VOP_UNLOCK(vn, 0);
486 error = vfs_busy(mp, 0);
487 vn_lock(vn, LK_EXCLUSIVE | LK_RETRY);
488 vfs_rel(mp);
489 if (error != 0)
490 PFS_RETURN(ENOENT);
491 if (vn->v_iflag & VI_DOOMED) {
492 vfs_unbusy(mp);
493 PFS_RETURN(ENOENT);
494 }
495 }
496 VOP_UNLOCK(vn, 0);
497 KASSERT(pd->pn_parent != NULL,
498 ("%s(): non-root directory has no parent", __func__));
499 /*
500 * This one is tricky. Descendents of procdir nodes
501 * inherit their parent's process affinity, but
502 * there's no easy reverse mapping. For simplicity,
503 * we assume that if this node is a procdir, its
504 * parent isn't (which is correct as long as
505 * descendents of procdir nodes are never procdir
506 * nodes themselves)
507 */
508 if (pd->pn_type == pfstype_procdir)
509 pid = NO_PID;
510 pfs_lock(pd);
511 pn = pd->pn_parent;
512 pfs_unlock(pd);
513 goto got_pnode;
514 }
515
516 pfs_lock(pd);
517
518 /* named node */
519 for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next)
520 if (pn->pn_type == pfstype_procdir)
521 pdn = pn;
522 else if (pn->pn_name[namelen] == '\0' &&
523 bcmp(pname, pn->pn_name, namelen) == 0) {
524 pfs_unlock(pd);
525 goto got_pnode;
526 }
527
528 /* process dependent node */
529 if ((pn = pdn) != NULL) {
530 pid = 0;
531 for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i)
532 if ((pid = pid * 10 + pname[i] - '') > PID_MAX)
533 break;
534 if (i == cnp->cn_namelen) {
535 pfs_unlock(pd);
536 goto got_pnode;
537 }
538 }
539
540 pfs_unlock(pd);
541
542 PFS_RETURN (ENOENT);
543
544 got_pnode:
545 pfs_assert_not_owned(pd);
546 pfs_assert_not_owned(pn);
547 visible = pfs_visible(curthread, pn, pid, false, NULL);
548 if (!visible) {
549 error = ENOENT;
550 goto failed;
551 }
552
553 error = pfs_vncache_alloc(mp, vpp, pn, pid);
554 if (error)
555 goto failed;
556
557 if (cnp->cn_flags & ISDOTDOT) {
558 vfs_unbusy(mp);
559 vn_lock(vn, LK_EXCLUSIVE | LK_RETRY);
560 if (vn->v_iflag & VI_DOOMED) {
561 vput(*vpp);
562 *vpp = NULL;
563 PFS_RETURN(ENOENT);
564 }
565 }
566 if (cnp->cn_flags & MAKEENTRY && !(vn->v_iflag & VI_DOOMED))
567 cache_enter(vn, *vpp, cnp);
568 PFS_RETURN (0);
569 failed:
570 if (cnp->cn_flags & ISDOTDOT) {
571 vfs_unbusy(mp);
572 vn_lock(vn, LK_EXCLUSIVE | LK_RETRY);
573 *vpp = NULL;
574 }
575 PFS_RETURN(error);
576 }
577
578 /*
579 * Open a file or directory.
580 */
581 static int
582 pfs_open(struct vop_open_args *va)
583 {
584 struct vnode *vn = va->a_vp;
585 struct pfs_vdata *pvd = vn->v_data;
586 struct pfs_node *pn = pvd->pvd_pn;
587 int mode = va->a_mode;
588
589 PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode));
590 pfs_assert_not_owned(pn);
591
592 /* check if the requested mode is permitted */
593 if (((mode & FREAD) && !(mode & PFS_RD)) ||
594 ((mode & FWRITE) && !(mode & PFS_WR)))
595 PFS_RETURN (EPERM);
596
597 /* we don't support locking */
598 if ((mode & O_SHLOCK) || (mode & O_EXLOCK))
599 PFS_RETURN (EOPNOTSUPP);
600
601 PFS_RETURN (0);
602 }
603
604 /*
605 * Read from a file
606 */
607 static int
608 pfs_read(struct vop_read_args *va)
609 {
610 struct vnode *vn = va->a_vp;
611 struct pfs_vdata *pvd = vn->v_data;
612 struct pfs_node *pn = pvd->pvd_pn;
613 struct uio *uio = va->a_uio;
614 struct proc *proc;
615 struct sbuf *sb = NULL;
616 int error, locked;
617 off_t buflen;
618
619 PFS_TRACE(("%s", pn->pn_name));
620 pfs_assert_not_owned(pn);
621
622 if (vn->v_type != VREG)
623 PFS_RETURN (EINVAL);
624 KASSERT_PN_IS_FILE(pn);
625
626 if (!(pn->pn_flags & PFS_RD))
627 PFS_RETURN (EBADF);
628
629 if (pn->pn_fill == NULL)
630 PFS_RETURN (EIO);
631
632 /*
633 * This is necessary because either process' privileges may
634 * have changed since the open() call.
635 */
636 if (!pfs_visible(curthread, pn, pvd->pvd_pid, false, &proc))
637 PFS_RETURN (EIO);
638 if (proc != NULL) {
639 _PHOLD(proc);
640 PROC_UNLOCK(proc);
641 }
642
643 vhold(vn);
644 locked = VOP_ISLOCKED(vn);
645 VOP_UNLOCK(vn, 0);
646
647 if (pn->pn_flags & PFS_RAWRD) {
648 PFS_TRACE(("%zd resid", uio->uio_resid));
649 error = pn_fill(curthread, proc, pn, NULL, uio);
650 PFS_TRACE(("%zd resid", uio->uio_resid));
651 goto ret;
652 }
653
654 if (uio->uio_resid < 0 || uio->uio_offset < 0 ||
655 uio->uio_resid > OFF_MAX - uio->uio_offset) {
656 error = EINVAL;
657 goto ret;
658 }
659 buflen = uio->uio_offset + uio->uio_resid;
660 if (buflen > MAXPHYS)
661 buflen = MAXPHYS;
662
663 sb = sbuf_new(sb, NULL, buflen + 1, 0);
664 if (sb == NULL) {
665 error = EIO;
666 goto ret;
667 }
668
669 error = pn_fill(curthread, proc, pn, sb, uio);
670
671 if (error) {
672 sbuf_delete(sb);
673 goto ret;
674 }
675
676 /*
677 * XXX: If the buffer overflowed, sbuf_len() will not return
678 * the data length. Then just use the full length because an
679 * overflowed sbuf must be full.
680 */
681 if (sbuf_finish(sb) == 0)
682 buflen = sbuf_len(sb);
683 error = uiomove_frombuf(sbuf_data(sb), buflen, uio);
684 sbuf_delete(sb);
685 ret:
686 vn_lock(vn, locked | LK_RETRY);
687 vdrop(vn);
688 if (proc != NULL)
689 PRELE(proc);
690 PFS_RETURN (error);
691 }
692
693 /*
694 * Iterate through directory entries
695 */
696 static int
697 pfs_iterate(struct thread *td, struct proc *proc, struct pfs_node *pd,
698 struct pfs_node **pn, struct proc **p)
699 {
700 int visible;
701
702 sx_assert(&allproc_lock, SX_SLOCKED);
703 pfs_assert_owned(pd);
704 again:
705 if (*pn == NULL) {
706 /* first node */
707 *pn = pd->pn_nodes;
708 } else if ((*pn)->pn_type != pfstype_procdir) {
709 /* next node */
710 *pn = (*pn)->pn_next;
711 }
712 if (*pn != NULL && (*pn)->pn_type == pfstype_procdir) {
713 /* next process */
714 if (*p == NULL)
715 *p = LIST_FIRST(&allproc);
716 else
717 *p = LIST_NEXT(*p, p_list);
718 /* out of processes: next node */
719 if (*p == NULL)
720 *pn = (*pn)->pn_next;
721 else
722 PROC_LOCK(*p);
723 }
724
725 if ((*pn) == NULL)
726 return (-1);
727
728 if (*p != NULL) {
729 visible = pfs_visible_proc(td, *pn, *p);
730 PROC_UNLOCK(*p);
731 } else if (proc != NULL) {
732 visible = pfs_visible_proc(td, *pn, proc);
733 } else {
734 visible = 1;
735 }
736 if (!visible)
737 goto again;
738
739 return (0);
740 }
741
742 /* Directory entry list */
743 struct pfsentry {
744 STAILQ_ENTRY(pfsentry) link;
745 struct dirent entry;
746 };
747 STAILQ_HEAD(pfsdirentlist, pfsentry);
748
749 /*
750 * Return directory entries.
751 */
752 static int
753 pfs_readdir(struct vop_readdir_args *va)
754 {
755 struct vnode *vn = va->a_vp;
756 struct pfs_vdata *pvd = vn->v_data;
757 struct pfs_node *pd = pvd->pvd_pn;
758 pid_t pid = pvd->pvd_pid;
759 struct proc *p, *proc;
760 struct pfs_node *pn;
761 struct uio *uio;
762 struct pfsentry *pfsent, *pfsent2;
763 struct pfsdirentlist lst;
764 off_t offset;
765 int error, i, resid;
766
767 STAILQ_INIT(&lst);
768 error = 0;
769 KASSERT(pd->pn_info == vn->v_mount->mnt_data,
770 ("%s(): pn_info does not match mountpoint", __func__));
771 PFS_TRACE(("%s pid %lu", pd->pn_name, (unsigned long)pid));
772 pfs_assert_not_owned(pd);
773
774 if (vn->v_type != VDIR)
775 PFS_RETURN (ENOTDIR);
776 KASSERT_PN_IS_DIR(pd);
777 uio = va->a_uio;
778
779 /* only allow reading entire entries */
780 offset = uio->uio_offset;
781 resid = uio->uio_resid;
782 if (offset < 0 || offset % PFS_DELEN != 0 ||
783 (resid && resid < PFS_DELEN))
784 PFS_RETURN (EINVAL);
785 if (resid == 0)
786 PFS_RETURN (0);
787
788 sx_slock(&allproc_lock);
789 pfs_lock(pd);
790
791 /* check if the directory is visible to the caller */
792 if (!pfs_visible(curthread, pd, pid, true, &proc)) {
793 sx_sunlock(&allproc_lock);
794 pfs_unlock(pd);
795 PFS_RETURN (ENOENT);
796 }
797 KASSERT(pid == NO_PID || proc != NULL,
798 ("%s(): no process for pid %lu", __func__, (unsigned long)pid));
799
800 /* skip unwanted entries */
801 for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) {
802 if (pfs_iterate(curthread, proc, pd, &pn, &p) == -1) {
803 /* nothing left... */
804 if (proc != NULL)
805 PROC_UNLOCK(proc);
806 pfs_unlock(pd);
807 sx_sunlock(&allproc_lock);
808 PFS_RETURN (0);
809 }
810 }
811
812 /* fill in entries */
813 while (pfs_iterate(curthread, proc, pd, &pn, &p) != -1 &&
814 resid >= PFS_DELEN) {
815 if ((pfsent = malloc(sizeof(struct pfsentry), M_IOV,
816 M_NOWAIT | M_ZERO)) == NULL) {
817 error = ENOMEM;
818 break;
819 }
820 pfsent->entry.d_reclen = PFS_DELEN;
821 pfsent->entry.d_fileno = pn_fileno(pn, pid);
822 /* PFS_DELEN was picked to fit PFS_NAMLEN */
823 for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i)
824 pfsent->entry.d_name[i] = pn->pn_name[i];
825 pfsent->entry.d_namlen = i;
826 switch (pn->pn_type) {
827 case pfstype_procdir:
828 KASSERT(p != NULL,
829 ("reached procdir node with p == NULL"));
830 pfsent->entry.d_namlen = snprintf(pfsent->entry.d_name,
831 PFS_NAMELEN, "%d", p->p_pid);
832 /* fall through */
833 case pfstype_root:
834 case pfstype_dir:
835 case pfstype_this:
836 case pfstype_parent:
837 pfsent->entry.d_type = DT_DIR;
838 break;
839 case pfstype_file:
840 pfsent->entry.d_type = DT_REG;
841 break;
842 case pfstype_symlink:
843 pfsent->entry.d_type = DT_LNK;
844 break;
845 default:
846 panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type);
847 }
848 PFS_TRACE(("%s", pfsent->entry.d_name));
849 dirent_terminate(&pfsent->entry);
850 STAILQ_INSERT_TAIL(&lst, pfsent, link);
851 offset += PFS_DELEN;
852 resid -= PFS_DELEN;
853 }
854 if (proc != NULL)
855 PROC_UNLOCK(proc);
856 pfs_unlock(pd);
857 sx_sunlock(&allproc_lock);
858 i = 0;
859 STAILQ_FOREACH_SAFE(pfsent, &lst, link, pfsent2) {
860 if (error == 0)
861 error = uiomove(&pfsent->entry, PFS_DELEN, uio);
862 free(pfsent, M_IOV);
863 i++;
864 }
865 PFS_TRACE(("%d bytes", i * PFS_DELEN));
866 PFS_RETURN (error);
867 }
868
869 /*
870 * Read a symbolic link
871 */
872 static int
873 pfs_readlink(struct vop_readlink_args *va)
874 {
875 struct vnode *vn = va->a_vp;
876 struct pfs_vdata *pvd = vn->v_data;
877 struct pfs_node *pn = pvd->pvd_pn;
878 struct uio *uio = va->a_uio;
879 struct proc *proc = NULL;
880 char buf[PATH_MAX];
881 struct sbuf sb;
882 int error, locked;
883
884 PFS_TRACE(("%s", pn->pn_name));
885 pfs_assert_not_owned(pn);
886
887 if (vn->v_type != VLNK)
888 PFS_RETURN (EINVAL);
889 KASSERT_PN_IS_LINK(pn);
890
891 if (pn->pn_fill == NULL)
892 PFS_RETURN (EIO);
893
894 if (pvd->pvd_pid != NO_PID) {
895 if ((proc = pfind(pvd->pvd_pid)) == NULL)
896 PFS_RETURN (EIO);
897 if (proc->p_flag & P_WEXIT) {
898 PROC_UNLOCK(proc);
899 PFS_RETURN (EIO);
900 }
901 _PHOLD(proc);
902 PROC_UNLOCK(proc);
903 }
904 vhold(vn);
905 locked = VOP_ISLOCKED(vn);
906 VOP_UNLOCK(vn, 0);
907
908 /* sbuf_new() can't fail with a static buffer */
909 sbuf_new(&sb, buf, sizeof buf, 0);
910
911 error = pn_fill(curthread, proc, pn, &sb, NULL);
912
913 if (proc != NULL)
914 PRELE(proc);
915 vn_lock(vn, locked | LK_RETRY);
916 vdrop(vn);
917
918 if (error) {
919 sbuf_delete(&sb);
920 PFS_RETURN (error);
921 }
922
923 if (sbuf_finish(&sb) != 0) {
924 sbuf_delete(&sb);
925 PFS_RETURN (ENAMETOOLONG);
926 }
927
928 error = uiomove_frombuf(sbuf_data(&sb), sbuf_len(&sb), uio);
929 sbuf_delete(&sb);
930 PFS_RETURN (error);
931 }
932
933 /*
934 * Reclaim a vnode
935 */
936 static int
937 pfs_reclaim(struct vop_reclaim_args *va)
938 {
939 struct vnode *vn = va->a_vp;
940 struct pfs_vdata *pvd = vn->v_data;
941 struct pfs_node *pn = pvd->pvd_pn;
942
943 PFS_TRACE(("%s", pn->pn_name));
944 pfs_assert_not_owned(pn);
945
946 return (pfs_vncache_free(va->a_vp));
947 }
948
949 /*
950 * Set attributes
951 */
952 static int
953 pfs_setattr(struct vop_setattr_args *va)
954 {
955 struct vnode *vn = va->a_vp;
956 struct pfs_vdata *pvd = vn->v_data;
957 struct pfs_node *pn = pvd->pvd_pn;
958
959 PFS_TRACE(("%s", pn->pn_name));
960 pfs_assert_not_owned(pn);
961
962 PFS_RETURN (EOPNOTSUPP);
963 }
964
965 /*
966 * Write to a file
967 */
968 static int
969 pfs_write(struct vop_write_args *va)
970 {
971 struct vnode *vn = va->a_vp;
972 struct pfs_vdata *pvd = vn->v_data;
973 struct pfs_node *pn = pvd->pvd_pn;
974 struct uio *uio = va->a_uio;
975 struct proc *proc;
976 struct sbuf sb;
977 int error;
978
979 PFS_TRACE(("%s", pn->pn_name));
980 pfs_assert_not_owned(pn);
981
982 if (vn->v_type != VREG)
983 PFS_RETURN (EINVAL);
984 KASSERT_PN_IS_FILE(pn);
985
986 if (!(pn->pn_flags & PFS_WR))
987 PFS_RETURN (EBADF);
988
989 if (pn->pn_fill == NULL)
990 PFS_RETURN (EIO);
991
992 /*
993 * This is necessary because either process' privileges may
994 * have changed since the open() call.
995 */
996 if (!pfs_visible(curthread, pn, pvd->pvd_pid, false, &proc))
997 PFS_RETURN (EIO);
998 if (proc != NULL) {
999 _PHOLD(proc);
1000 PROC_UNLOCK(proc);
1001 }
1002
1003 if (pn->pn_flags & PFS_RAWWR) {
1004 error = pn_fill(curthread, proc, pn, NULL, uio);
1005 if (proc != NULL)
1006 PRELE(proc);
1007 PFS_RETURN (error);
1008 }
1009
1010 sbuf_uionew(&sb, uio, &error);
1011 if (error) {
1012 if (proc != NULL)
1013 PRELE(proc);
1014 PFS_RETURN (error);
1015 }
1016
1017 error = pn_fill(curthread, proc, pn, &sb, uio);
1018
1019 sbuf_delete(&sb);
1020 if (proc != NULL)
1021 PRELE(proc);
1022 PFS_RETURN (error);
1023 }
1024
1025 /*
1026 * Vnode operations
1027 */
1028 struct vop_vector pfs_vnodeops = {
1029 .vop_default = &default_vnodeops,
1030
1031 .vop_access = pfs_access,
1032 .vop_cachedlookup = pfs_lookup,
1033 .vop_close = pfs_close,
1034 .vop_create = VOP_EOPNOTSUPP,
1035 .vop_getattr = pfs_getattr,
1036 .vop_getextattr = pfs_getextattr,
1037 .vop_ioctl = pfs_ioctl,
1038 .vop_link = VOP_EOPNOTSUPP,
1039 .vop_lookup = vfs_cache_lookup,
1040 .vop_mkdir = VOP_EOPNOTSUPP,
1041 .vop_mknod = VOP_EOPNOTSUPP,
1042 .vop_open = pfs_open,
1043 .vop_read = pfs_read,
1044 .vop_readdir = pfs_readdir,
1045 .vop_readlink = pfs_readlink,
1046 .vop_reclaim = pfs_reclaim,
1047 .vop_remove = VOP_EOPNOTSUPP,
1048 .vop_rename = VOP_EOPNOTSUPP,
1049 .vop_rmdir = VOP_EOPNOTSUPP,
1050 .vop_setattr = pfs_setattr,
1051 .vop_symlink = VOP_EOPNOTSUPP,
1052 .vop_vptocnp = pfs_vptocnp,
1053 .vop_write = pfs_write,
1054 /* XXX I've probably forgotten a few that need VOP_EOPNOTSUPP */
1055 };
Cache object: 06075b79f074c1346981cece1c5ee0c7
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