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[dragonfly.git] / sys / vfs / procfs / procfs_vnops.c
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1/*
2 * Copyright (c) 1993, 1995 Jan-Simon Pendry
3 * Copyright (c) 1993, 1995
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Jan-Simon Pendry.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed by the University of
20 * California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95
38 *
39 * $FreeBSD: src/sys/miscfs/procfs/procfs_vnops.c,v 1.76.2.7 2002/01/22 17:22:59 nectar Exp $
3c37c940 40 * $DragonFly: src/sys/vfs/procfs/procfs_vnops.c,v 1.43 2007/05/06 19:23:35 dillon Exp $
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41 */
42
43/*
44 * procfs vnode interface
45 */
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/time.h>
50#include <sys/kernel.h>
51#include <sys/lock.h>
52#include <sys/fcntl.h>
53#include <sys/proc.h>
54#include <sys/signalvar.h>
55#include <sys/vnode.h>
56#include <sys/uio.h>
57#include <sys/mount.h>
58#include <sys/namei.h>
59#include <sys/dirent.h>
60#include <sys/malloc.h>
527fddf7 61#include <sys/reg.h>
984263bc 62#include <vm/vm_zone.h>
1f2de5d4 63#include <vfs/procfs/procfs.h>
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64#include <sys/pioctl.h>
65
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66#include <machine/limits.h>
67
a6ee311a 68static int procfs_access (struct vop_access_args *);
66a1ddf5 69static int procfs_badop (struct vop_generic_args *);
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70static int procfs_bmap (struct vop_bmap_args *);
71static int procfs_close (struct vop_close_args *);
72static int procfs_getattr (struct vop_getattr_args *);
73static int procfs_inactive (struct vop_inactive_args *);
74static int procfs_ioctl (struct vop_ioctl_args *);
e62afb5f 75static int procfs_lookup (struct vop_old_lookup_args *);
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76static int procfs_open (struct vop_open_args *);
77static int procfs_print (struct vop_print_args *);
78static int procfs_readdir (struct vop_readdir_args *);
79static int procfs_readlink (struct vop_readlink_args *);
80static int procfs_reclaim (struct vop_reclaim_args *);
81static int procfs_setattr (struct vop_setattr_args *);
984263bc 82
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83static int procfs_readdir_proc(struct vop_readdir_args *);
84static int procfs_readdir_root(struct vop_readdir_args *);
85
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86/*
87 * procfs vnode operations.
88 */
89struct vop_ops procfs_vnode_vops = {
90 .vop_default = vop_defaultop,
91 .vop_access = procfs_access,
92 .vop_advlock = (void *)procfs_badop,
93 .vop_bmap = procfs_bmap,
94 .vop_close = procfs_close,
95 .vop_old_create = (void *)procfs_badop,
96 .vop_getattr = procfs_getattr,
97 .vop_inactive = procfs_inactive,
98 .vop_old_link = (void *)procfs_badop,
99 .vop_old_lookup = procfs_lookup,
100 .vop_old_mkdir = (void *)procfs_badop,
101 .vop_old_mknod = (void *)procfs_badop,
102 .vop_open = procfs_open,
103 .vop_pathconf = vop_stdpathconf,
104 .vop_print = procfs_print,
105 .vop_read = procfs_rw,
106 .vop_readdir = procfs_readdir,
107 .vop_readlink = procfs_readlink,
108 .vop_reclaim = procfs_reclaim,
109 .vop_old_remove = (void *)procfs_badop,
110 .vop_old_rename = (void *)procfs_badop,
111 .vop_old_rmdir = (void *)procfs_badop,
112 .vop_setattr = procfs_setattr,
113 .vop_old_symlink = (void *)procfs_badop,
114 .vop_write = (void *)procfs_rw,
115 .vop_ioctl = procfs_ioctl
116};
117
118
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119/*
120 * This is a list of the valid names in the
121 * process-specific sub-directories. It is
122 * used in procfs_lookup and procfs_readdir
123 */
124static struct proc_target {
125 u_char pt_type;
126 u_char pt_namlen;
127 char *pt_name;
128 pfstype pt_pfstype;
c7e98b2f 129 int (*pt_valid) (struct lwp *p);
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130} proc_targets[] = {
131#define N(s) sizeof(s)-1, s
132 /* name type validp */
133 { DT_DIR, N("."), Pproc, NULL },
134 { DT_DIR, N(".."), Proot, NULL },
135 { DT_REG, N("mem"), Pmem, NULL },
136 { DT_REG, N("regs"), Pregs, procfs_validregs },
137 { DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs },
138 { DT_REG, N("dbregs"), Pdbregs, procfs_validdbregs },
139 { DT_REG, N("ctl"), Pctl, NULL },
140 { DT_REG, N("status"), Pstatus, NULL },
141 { DT_REG, N("note"), Pnote, NULL },
142 { DT_REG, N("notepg"), Pnotepg, NULL },
143 { DT_REG, N("map"), Pmap, procfs_validmap },
144 { DT_REG, N("etype"), Ptype, procfs_validtype },
145 { DT_REG, N("cmdline"), Pcmdline, NULL },
146 { DT_REG, N("rlimit"), Prlimit, NULL },
147 { DT_LNK, N("file"), Pfile, NULL },
148#undef N
149};
150static const int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]);
151
a6ee311a 152static pid_t atopid (const char *, u_int);
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153
154/*
155 * set things up for doing i/o on
156 * the pfsnode (vp). (vp) is locked
157 * on entry, and should be left locked
158 * on exit.
159 *
160 * for procfs we don't need to do anything
161 * in particular for i/o. all that is done
162 * is to support exclusive open on process
163 * memory images.
ac424f9b 164 *
87de5057 165 * procfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred)
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166 */
167static int
ac424f9b 168procfs_open(struct vop_open_args *ap)
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169{
170 struct pfsnode *pfs = VTOPFS(ap->a_vp);
171 struct proc *p1, *p2;
172
173 p2 = PFIND(pfs->pfs_pid);
174 if (p2 == NULL)
175 return (ENOENT);
41c20dac 176 if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred))
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177 return (ENOENT);
178
179 switch (pfs->pfs_type) {
180 case Pmem:
181 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) ||
182 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE)))
183 return (EBUSY);
184
87de5057 185 p1 = curproc;
dadab5e9 186 KKASSERT(p1);
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187 /* Can't trace a process that's currently exec'ing. */
188 if ((p2->p_flag & P_INEXEC) != 0)
189 return EAGAIN;
41c20dac 190 if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred))
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191 return (EPERM);
192
193 if (ap->a_mode & FWRITE)
194 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL);
195
8ddc6004 196 break;
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197
198 default:
199 break;
200 }
201
8ddc6004 202 return (vop_stdopen(ap));
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203}
204
205/*
206 * close the pfsnode (vp) after doing i/o.
207 * (vp) is not locked on entry or exit.
208 *
209 * nothing to do for procfs other than undo
210 * any exclusive open flag (see _open above).
ac424f9b 211 *
87de5057 212 * procfs_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred)
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213 */
214static int
ac424f9b 215procfs_close(struct vop_close_args *ap)
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216{
217 struct pfsnode *pfs = VTOPFS(ap->a_vp);
218 struct proc *p;
219
220 switch (pfs->pfs_type) {
221 case Pmem:
222 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL))
223 pfs->pfs_flags &= ~(FWRITE|O_EXCL);
224 /*
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225 * v_opencount determines the last real close on the vnode.
226 *
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227 * If this is the last close, then it checks to see if
228 * the target process has PF_LINGER set in p_pfsflags,
229 * if this is *not* the case, then the process' stop flags
230 * are cleared, and the process is woken up. This is
231 * to help prevent the case where a process has been
232 * told to stop on an event, but then the requesting process
233 * has gone away or forgotten about it.
234 */
3c37c940 235 if ((ap->a_vp->v_opencount < 2)
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236 && (p = pfind(pfs->pfs_pid))
237 && !(p->p_pfsflags & PF_LINGER)) {
238 p->p_stops = 0;
239 p->p_step = 0;
240 wakeup(&p->p_step);
241 }
242 break;
243 default:
244 break;
245 }
246
8ddc6004 247 return (vop_stdclose(ap));
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248}
249
250/*
251 * do an ioctl operation on a pfsnode (vp).
252 * (vp) is not locked on entry or exit.
253 */
254static int
ac424f9b 255procfs_ioctl(struct vop_ioctl_args *ap)
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256{
257 struct pfsnode *pfs = VTOPFS(ap->a_vp);
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258 struct proc *procp;
259 struct proc *p;
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260 int error;
261 int signo;
262 struct procfs_status *psp;
263 unsigned char flags;
264
984263bc 265 procp = pfind(pfs->pfs_pid);
dadab5e9 266 if (procp == NULL)
984263bc 267 return ENOTTY;
87de5057 268 p = curproc;
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269 if (p == NULL)
270 return EINVAL;
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271
272 /* Can't trace a process that's currently exec'ing. */
273 if ((procp->p_flag & P_INEXEC) != 0)
274 return EAGAIN;
41c20dac 275 if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred))
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276 return EPERM;
277
278 switch (ap->a_command) {
279 case PIOCBIS:
280 procp->p_stops |= *(unsigned int*)ap->a_data;
281 break;
282 case PIOCBIC:
283 procp->p_stops &= ~*(unsigned int*)ap->a_data;
284 break;
285 case PIOCSFL:
286 /*
287 * NFLAGS is "non-suser_xxx flags" -- currently, only
288 * PFS_ISUGID ("ignore set u/g id");
289 */
290#define NFLAGS (PF_ISUGID)
291 flags = (unsigned char)*(unsigned int*)ap->a_data;
dadab5e9 292 if (flags & NFLAGS && (error = suser_cred(ap->a_cred, 0)))
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293 return error;
294 procp->p_pfsflags = flags;
295 break;
296 case PIOCGFL:
297 *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags;
298 break;
299 case PIOCSTATUS:
300 psp = (struct procfs_status *)ap->a_data;
301 psp->state = (procp->p_step == 0);
302 psp->flags = procp->p_pfsflags;
303 psp->events = procp->p_stops;
304 if (procp->p_step) {
305 psp->why = procp->p_stype;
306 psp->val = procp->p_xstat;
307 } else {
308 psp->why = psp->val = 0; /* Not defined values */
309 }
310 break;
311 case PIOCWAIT:
312 psp = (struct procfs_status *)ap->a_data;
313 if (procp->p_step == 0) {
377d4740 314 error = tsleep(&procp->p_stype, PCATCH, "piocwait", 0);
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315 if (error)
316 return error;
317 }
318 psp->state = 1; /* It stopped */
319 psp->flags = procp->p_pfsflags;
320 psp->events = procp->p_stops;
321 psp->why = procp->p_stype; /* why it stopped */
322 psp->val = procp->p_xstat; /* any extra info */
323 break;
324 case PIOCCONT: /* Restart a proc */
325 if (procp->p_step == 0)
326 return EINVAL; /* Can only start a stopped process */
327 if ((signo = *(int*)ap->a_data) != 0) {
328 if (signo >= NSIG || signo <= 0)
329 return EINVAL;
84204577 330 ksignal(procp, signo);
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331 }
332 procp->p_step = 0;
333 wakeup(&procp->p_step);
334 break;
335 default:
336 return (ENOTTY);
337 }
338 return 0;
339}
340
341/*
342 * do block mapping for pfsnode (vp).
343 * since we don't use the buffer cache
344 * for procfs this function should never
345 * be called. in any case, it's not clear
346 * what part of the kernel ever makes use
347 * of this function. for sanity, this is the
348 * usual no-op bmap, although returning
349 * (EIO) would be a reasonable alternative.
ac424f9b 350 *
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351 * procfs_bmap(struct vnode *a_vp, off_t a_loffset, struct vnode **a_vpp,
352 * off_t *a_doffsetp, int *a_runp)
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353 */
354static int
ac424f9b 355procfs_bmap(struct vop_bmap_args *ap)
984263bc 356{
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357 if (ap->a_vpp != NULL)
358 *ap->a_vpp = ap->a_vp;
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359 if (ap->a_doffsetp != NULL)
360 *ap->a_doffsetp = ap->a_loffset;
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361 if (ap->a_runp != NULL)
362 *ap->a_runp = 0;
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363 if (ap->a_runb != NULL)
364 *ap->a_runb = 0;
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365 return (0);
366}
367
368/*
369 * procfs_inactive is called when the pfsnode
370 * is vrele'd and the reference count goes
371 * to zero. (vp) will be on the vnode free
372 * list, so to get it back vget() must be
373 * used.
374 *
375 * (vp) is locked on entry, but must be unlocked on exit.
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376 *
377 * procfs_inactive(struct vnode *a_vp, struct thread *a_td)
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378 */
379static int
ac424f9b 380procfs_inactive(struct vop_inactive_args *ap)
984263bc 381{
5fd012e0 382 /*struct vnode *vp = ap->a_vp;*/
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383
384 return (0);
385}
386
387/*
388 * _reclaim is called when getnewvnode()
389 * wants to make use of an entry on the vnode
390 * free list. at this time the filesystem needs
391 * to free any private data and remove the node
392 * from any private lists.
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393 *
394 * procfs_reclaim(struct vnode *a_vp)
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395 */
396static int
ac424f9b 397procfs_reclaim(struct vop_reclaim_args *ap)
984263bc 398{
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399 return (procfs_freevp(ap->a_vp));
400}
401
402/*
403 * _print is used for debugging.
404 * just print a readable description
405 * of (vp).
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406 *
407 * procfs_print(struct vnode *a_vp)
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408 */
409static int
ac424f9b 410procfs_print(struct vop_print_args *ap)
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411{
412 struct pfsnode *pfs = VTOPFS(ap->a_vp);
413
086c1d7e 414 kprintf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n",
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415 pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags);
416 return (0);
417}
418
419/*
420 * generic entry point for unsupported operations
421 */
422static int
66a1ddf5 423procfs_badop(struct vop_generic_args *ap)
984263bc 424{
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425 return (EIO);
426}
427
428/*
429 * Invent attributes for pfsnode (vp) and store
430 * them in (vap).
431 * Directories lengths are returned as zero since
432 * any real length would require the genuine size
433 * to be computed, and nothing cares anyway.
434 *
435 * this is relatively minimal for procfs.
ac424f9b
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436 *
437 * procfs_getattr(struct vnode *a_vp, struct vattr *a_vap,
438 * struct ucred *a_cred, struct thread *a_td)
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439 */
440static int
ac424f9b 441procfs_getattr(struct vop_getattr_args *ap)
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442{
443 struct pfsnode *pfs = VTOPFS(ap->a_vp);
444 struct vattr *vap = ap->a_vap;
445 struct proc *procp;
446 int error;
447
448 /*
449 * First make sure that the process and its credentials
450 * still exist.
451 */
452 switch (pfs->pfs_type) {
453 case Proot:
454 case Pcurproc:
455 procp = 0;
456 break;
457
458 default:
459 procp = PFIND(pfs->pfs_pid);
41c20dac 460 if (procp == NULL || procp->p_ucred == NULL)
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461 return (ENOENT);
462 }
463
464 error = 0;
465
466 /* start by zeroing out the attributes */
467 VATTR_NULL(vap);
468
469 /* next do all the common fields */
470 vap->va_type = ap->a_vp->v_type;
471 vap->va_mode = pfs->pfs_mode;
472 vap->va_fileid = pfs->pfs_fileno;
473 vap->va_flags = 0;
474 vap->va_blocksize = PAGE_SIZE;
475 vap->va_bytes = vap->va_size = 0;
476 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0];
477
478 /*
479 * Make all times be current TOD.
480 * It would be possible to get the process start
481 * time from the p_stat structure, but there's
482 * no "file creation" time stamp anyway, and the
483 * p_stat structure is not addressible if u. gets
484 * swapped out for that process.
485 */
486 nanotime(&vap->va_ctime);
487 vap->va_atime = vap->va_mtime = vap->va_ctime;
488
489 /*
490 * If the process has exercised some setuid or setgid
491 * privilege, then rip away read/write permission so
492 * that only root can gain access.
493 */
494 switch (pfs->pfs_type) {
495 case Pctl:
496 case Pregs:
497 case Pfpregs:
498 case Pdbregs:
499 case Pmem:
500 if (procp->p_flag & P_SUGID)
501 vap->va_mode &= ~((VREAD|VWRITE)|
502 ((VREAD|VWRITE)>>3)|
503 ((VREAD|VWRITE)>>6));
504 break;
505 default:
506 break;
507 }
508
509 /*
510 * now do the object specific fields
511 *
512 * The size could be set from struct reg, but it's hardly
513 * worth the trouble, and it puts some (potentially) machine
514 * dependent data into this machine-independent code. If it
515 * becomes important then this function should break out into
516 * a per-file stat function in the corresponding .c file.
517 */
518
519 vap->va_nlink = 1;
520 if (procp) {
521 vap->va_uid = procp->p_ucred->cr_uid;
522 vap->va_gid = procp->p_ucred->cr_gid;
523 }
524
525 switch (pfs->pfs_type) {
526 case Proot:
527 /*
528 * Set nlink to 1 to tell fts(3) we don't actually know.
529 */
530 vap->va_nlink = 1;
531 vap->va_uid = 0;
532 vap->va_gid = 0;
533 vap->va_size = vap->va_bytes = DEV_BSIZE;
534 break;
535
536 case Pcurproc: {
537 char buf[16]; /* should be enough */
538 vap->va_uid = 0;
539 vap->va_gid = 0;
540 vap->va_size = vap->va_bytes =
f8c7a42d 541 ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
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542 break;
543 }
544
545 case Pproc:
546 vap->va_nlink = nproc_targets;
547 vap->va_size = vap->va_bytes = DEV_BSIZE;
548 break;
549
550 case Pfile: {
551 char *fullpath, *freepath;
541044dc 552 error = vn_fullpath(procp, NULL, &fullpath, &freepath);
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553 if (error == 0) {
554 vap->va_size = strlen(fullpath);
efda3bd0 555 kfree(freepath, M_TEMP);
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556 } else {
557 vap->va_size = sizeof("unknown") - 1;
558 error = 0;
559 }
560 vap->va_bytes = vap->va_size;
561 break;
562 }
563
564 case Pmem:
565 /*
566 * If we denied owner access earlier, then we have to
567 * change the owner to root - otherwise 'ps' and friends
568 * will break even though they are setgid kmem. *SIGH*
569 */
570 if (procp->p_flag & P_SUGID)
571 vap->va_uid = 0;
572 else
573 vap->va_uid = procp->p_ucred->cr_uid;
574 break;
575
576 case Pregs:
577 vap->va_bytes = vap->va_size = sizeof(struct reg);
578 break;
579
580 case Pfpregs:
581 vap->va_bytes = vap->va_size = sizeof(struct fpreg);
582 break;
583
584 case Pdbregs:
585 vap->va_bytes = vap->va_size = sizeof(struct dbreg);
586 break;
587
588 case Ptype:
589 case Pmap:
590 case Pctl:
591 case Pstatus:
592 case Pnote:
593 case Pnotepg:
594 case Pcmdline:
595 case Prlimit:
596 break;
597
598 default:
599 panic("procfs_getattr");
600 }
601
602 return (error);
603}
604
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605/*
606 * procfs_setattr(struct vnode *a_vp, struct vattr *a_vap,
607 * struct ucred *a_cred, struct thread *a_td)
608 */
984263bc 609static int
ac424f9b 610procfs_setattr(struct vop_setattr_args *ap)
984263bc 611{
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612 if (ap->a_vap->va_flags != VNOVAL)
613 return (EOPNOTSUPP);
614
615 /*
616 * just fake out attribute setting
617 * it's not good to generate an error
618 * return, otherwise things like creat()
619 * will fail when they try to set the
620 * file length to 0. worse, this means
621 * that echo $note > /proc/$pid/note will fail.
622 */
623
624 return (0);
625}
626
627/*
628 * implement access checking.
629 *
630 * something very similar to this code is duplicated
631 * throughout the 4bsd kernel and should be moved
632 * into kern/vfs_subr.c sometime.
633 *
634 * actually, the check for super-user is slightly
635 * broken since it will allow read access to write-only
636 * objects. this doesn't cause any particular trouble
637 * but does mean that the i/o entry points need to check
638 * that the operation really does make sense.
ac424f9b
CP
639 *
640 * procfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred,
641 * struct thread *a_td)
984263bc
MD
642 */
643static int
ac424f9b 644procfs_access(struct vop_access_args *ap)
984263bc
MD
645{
646 struct vattr *vap;
647 struct vattr vattr;
648 int error;
649
650 /*
651 * If you're the super-user,
652 * you always get access.
653 */
654 if (ap->a_cred->cr_uid == 0)
655 return (0);
656
657 vap = &vattr;
87de5057 658 error = VOP_GETATTR(ap->a_vp, vap);
984263bc
MD
659 if (error)
660 return (error);
661
662 /*
663 * Access check is based on only one of owner, group, public.
664 * If not owner, then check group. If not a member of the
665 * group, then check public access.
666 */
667 if (ap->a_cred->cr_uid != vap->va_uid) {
668 gid_t *gp;
669 int i;
670
671 ap->a_mode >>= 3;
672 gp = ap->a_cred->cr_groups;
673 for (i = 0; i < ap->a_cred->cr_ngroups; i++, gp++)
674 if (vap->va_gid == *gp)
675 goto found;
676 ap->a_mode >>= 3;
677found:
678 ;
679 }
680
681 if ((vap->va_mode & ap->a_mode) == ap->a_mode)
682 return (0);
683
684 return (EACCES);
685}
686
687/*
3446c007
MD
688 * lookup. this is incredibly complicated in the general case, however
689 * for most pseudo-filesystems very little needs to be done.
ac424f9b
CP
690 *
691 * procfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
692 * struct componentname *a_cnp)
984263bc
MD
693 */
694static int
e62afb5f 695procfs_lookup(struct vop_old_lookup_args *ap)
984263bc
MD
696{
697 struct componentname *cnp = ap->a_cnp;
698 struct vnode **vpp = ap->a_vpp;
699 struct vnode *dvp = ap->a_dvp;
700 char *pname = cnp->cn_nameptr;
701 /* struct proc *curp = cnp->cn_proc; */
702 struct proc_target *pt;
703 pid_t pid;
704 struct pfsnode *pfs;
705 struct proc *p;
c7e98b2f 706 struct lwp *lp;
984263bc 707 int i;
3446c007 708 int error;
984263bc
MD
709
710 *vpp = NULL;
711
2b69e610 712 if (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME)
984263bc
MD
713 return (EROFS);
714
3446c007 715 error = 0;
984263bc
MD
716 if (cnp->cn_namelen == 1 && *pname == '.') {
717 *vpp = dvp;
3446c007
MD
718 vref(*vpp);
719 goto out;
984263bc
MD
720 }
721
722 pfs = VTOPFS(dvp);
723 switch (pfs->pfs_type) {
724 case Proot:
2b69e610 725 if (cnp->cn_flags & CNP_ISDOTDOT)
984263bc
MD
726 return (EIO);
727
3446c007
MD
728 if (CNEQ(cnp, "curproc", 7)) {
729 error = procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc);
730 goto out;
731 }
984263bc
MD
732
733 pid = atopid(pname, cnp->cn_namelen);
734 if (pid == NO_PID)
735 break;
736
737 p = PFIND(pid);
738 if (p == NULL)
739 break;
740
dcab9ef0
JS
741 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred))
742 break;
743
28c57d20
HP
744 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 &&
745 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid)
746 break;
747
3446c007
MD
748 error = procfs_allocvp(dvp->v_mount, vpp, pid, Pproc);
749 goto out;
984263bc
MD
750
751 case Pproc:
3446c007
MD
752 if (cnp->cn_flags & CNP_ISDOTDOT) {
753 error = procfs_root(dvp->v_mount, vpp);
754 goto out;
755 }
984263bc
MD
756
757 p = PFIND(pfs->pfs_pid);
758 if (p == NULL)
759 break;
c7e98b2f
SS
760 /* XXX lwp */
761 lp = FIRST_LWP_IN_PROC(p);
984263bc 762
dcab9ef0
JS
763 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred))
764 break;
765
28c57d20
HP
766 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 &&
767 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid)
768 break;
769
984263bc
MD
770 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) {
771 if (cnp->cn_namelen == pt->pt_namlen &&
772 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 &&
c7e98b2f 773 (pt->pt_valid == NULL || (*pt->pt_valid)(lp)))
984263bc
MD
774 goto found;
775 }
776 break;
777 found:
3446c007
MD
778 error = procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid,
779 pt->pt_pfstype);
780 goto out;
984263bc
MD
781
782 default:
3446c007
MD
783 error = ENOTDIR;
784 goto out;
984263bc 785 }
3446c007
MD
786 if (cnp->cn_nameiop == NAMEI_LOOKUP)
787 error = ENOENT;
788 else
789 error = EROFS;
790 /*
791 * If no error occured *vpp will hold a referenced locked vnode.
aa723195
MD
792 * dvp was passed to us locked and *vpp must be returned locked.
793 * If *vpp != dvp then we should unlock dvp if (1) this is not the
794 * last component or (2) CNP_LOCKPARENT is not set.
3446c007
MD
795 */
796out:
aa723195
MD
797 if (error == 0 && *vpp != dvp) {
798 if ((cnp->cn_flags & CNP_LOCKPARENT) == 0) {
799 cnp->cn_flags |= CNP_PDIRUNLOCK;
a11aaa81 800 vn_unlock(dvp);
3446c007
MD
801 }
802 }
803 return (error);
984263bc
MD
804}
805
806/*
807 * Does this process have a text file?
808 */
4d4fb029 809int
c7e98b2f 810procfs_validfile(struct lwp *lp)
984263bc 811{
c7e98b2f 812 return (procfs_findtextvp(lp->lwp_proc) != NULLVP);
984263bc
MD
813}
814
815/*
816 * readdir() returns directory entries from pfsnode (vp).
817 *
818 * We generate just one directory entry at a time, as it would probably
819 * not pay off to buffer several entries locally to save uiomove calls.
ac424f9b
CP
820 *
821 * procfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred,
822 * int *a_eofflag, int *a_ncookies, u_long **a_cookies)
984263bc
MD
823 */
824static int
ac424f9b 825procfs_readdir(struct vop_readdir_args *ap)
984263bc 826{
984263bc 827 struct pfsnode *pfs;
dcab9ef0 828 int error;
984263bc 829
dcab9ef0 830 if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX)
984263bc 831 return (EINVAL);
885ecb13
MD
832 if ((error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY)) != 0)
833 return (error);
dcab9ef0 834 pfs = VTOPFS(ap->a_vp);
984263bc
MD
835
836 switch (pfs->pfs_type) {
dcab9ef0 837 case Pproc:
885ecb13
MD
838 /*
839 * this is for the process-specific sub-directories.
840 * all that is needed to is copy out all the entries
841 * from the procent[] table (top of this file).
842 */
dcab9ef0
JS
843 error = procfs_readdir_proc(ap);
844 break;
dcab9ef0 845 case Proot:
885ecb13
MD
846 /*
847 * this is for the root of the procfs filesystem
848 * what is needed is a special entry for "curproc"
849 * followed by an entry for each process on allproc
850 */
dcab9ef0 851 error = procfs_readdir_root(ap);
984263bc 852 break;
984263bc
MD
853 default:
854 error = ENOTDIR;
855 break;
856 }
857
885ecb13 858 vn_unlock(ap->a_vp);
984263bc
MD
859 return (error);
860}
861
dcab9ef0
JS
862static int
863procfs_readdir_proc(struct vop_readdir_args *ap)
864{
865 struct pfsnode *pfs;
866 int error, i, retval;
867 struct proc *p;
c7e98b2f 868 struct lwp *lp;
dcab9ef0
JS
869 struct proc_target *pt;
870 struct uio *uio = ap->a_uio;
871
872 pfs = VTOPFS(ap->a_vp);
873 p = PFIND(pfs->pfs_pid);
874 if (p == NULL)
875 return(0);
876 if (!PRISON_CHECK(ap->a_cred, p->p_ucred))
877 return(0);
c7e98b2f
SS
878 /* XXX lwp */
879 lp = FIRST_LWP_IN_PROC(p);
dcab9ef0
JS
880
881 error = 0;
fb0466c9
MD
882 i = (int)uio->uio_offset;
883 if (i < 0)
884 return (EINVAL);
dcab9ef0
JS
885
886 for (pt = &proc_targets[i];
887 !error && uio->uio_resid > 0 && i < nproc_targets; pt++, i++) {
c7e98b2f 888 if (pt->pt_valid && (*pt->pt_valid)(lp) == 0)
dcab9ef0
JS
889 continue;
890
891 retval = vop_write_dirent(&error, uio,
892 PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype), pt->pt_type,
893 pt->pt_namlen, pt->pt_name);
894 if (retval)
895 break;
896 }
897
fb0466c9 898 uio->uio_offset = (off_t)i;
dcab9ef0
JS
899
900 return(0);
901}
902
51e64ff2
MD
903struct procfs_readdir_root_info {
904 int error;
905 int i;
906 int pcnt;
907 struct uio *uio;
908 struct ucred *cred;
909};
910
911static int procfs_readdir_root_callback(struct proc *p, void *data);
912
dcab9ef0
JS
913static int
914procfs_readdir_root(struct vop_readdir_args *ap)
915{
51e64ff2 916 struct procfs_readdir_root_info info;
dcab9ef0 917 struct uio *uio = ap->a_uio;
51e64ff2
MD
918 int res;
919
920 info.error = 0;
fb0466c9
MD
921 info.i = (int)uio->uio_offset;
922
923 if (info.i < 0)
924 return (EINVAL);
925
51e64ff2
MD
926 info.pcnt = 0;
927 info.uio = uio;
928 info.cred = ap->a_cred;
51e64ff2
MD
929 while (info.pcnt < 3) {
930 res = procfs_readdir_root_callback(NULL, &info);
931 if (res < 0)
932 break;
933 }
934 if (res >= 0)
935 allproc_scan(procfs_readdir_root_callback, &info);
fb0466c9 936 uio->uio_offset = (off_t)info.i;
51e64ff2
MD
937
938 return (info.error);
939}
940
941static int
942procfs_readdir_root_callback(struct proc *p, void *data)
943{
944 struct procfs_readdir_root_info *info = data;
945 struct uio *uio;
946 int retval;
dcab9ef0
JS
947 ino_t d_ino;
948 const char *d_name;
949 char d_name_pid[20];
950 size_t d_namlen;
951 uint8_t d_type;
952
51e64ff2 953 uio = info->uio;
dcab9ef0 954
51e64ff2
MD
955 if (uio->uio_resid <= 0 || info->error)
956 return(-1);
dcab9ef0 957
51e64ff2
MD
958 switch (info->pcnt) {
959 case 0: /* `.' */
960 d_ino = PROCFS_FILENO(0, Proot);
961 d_name = ".";
962 d_namlen = 1;
963 d_type = DT_DIR;
964 break;
965 case 1: /* `..' */
966 d_ino = PROCFS_FILENO(0, Proot);
967 d_name = "..";
968 d_namlen = 2;
969 d_type = DT_DIR;
970 break;
dcab9ef0 971
51e64ff2
MD
972 case 2:
973 d_ino = PROCFS_FILENO(0, Pcurproc);
974 d_namlen = 7;
975 d_name = "curproc";
976 d_type = DT_LNK;
977 break;
dcab9ef0 978
51e64ff2
MD
979
980 default:
981 if (!PRISON_CHECK(info->cred, p->p_ucred))
982 return(0);
983 if (ps_showallprocs == 0 &&
984 info->cred->cr_uid != 0 &&
985 info->cred->cr_uid != p->p_ucred->cr_uid) {
986 return(0);
dcab9ef0
JS
987 }
988
51e64ff2
MD
989 /*
990 * Skip entries we have already returned (optimization)
991 */
992 if (info->pcnt < info->i) {
993 ++info->pcnt;
994 return(0);
995 }
996
997 d_ino = PROCFS_FILENO(p->p_pid, Pproc);
f8c7a42d 998 d_namlen = ksnprintf(d_name_pid, sizeof(d_name_pid),
51e64ff2
MD
999 "%ld", (long)p->p_pid);
1000 d_name = d_name_pid;
1001 d_type = DT_DIR;
1002 break;
dcab9ef0 1003 }
51e64ff2
MD
1004
1005 /*
1006 * Skip entries we have already returned (optimization)
1007 */
1008 if (info->pcnt < info->i) {
1009 ++info->pcnt;
1010 return(0);
1011 }
1012
1013 retval = vop_write_dirent(&info->error, uio,
1014 d_ino, d_type, d_namlen, d_name);
1015 if (retval)
1016 return(-1);
1017 ++info->pcnt;
1018 ++info->i;
dcab9ef0
JS
1019 return(0);
1020}
1021
984263bc
MD
1022/*
1023 * readlink reads the link of `curproc' or `file'
1024 */
1025static int
ac424f9b 1026procfs_readlink(struct vop_readlink_args *ap)
984263bc
MD
1027{
1028 char buf[16]; /* should be enough */
1029 struct proc *procp;
1030 struct vnode *vp = ap->a_vp;
1031 struct pfsnode *pfs = VTOPFS(vp);
1032 char *fullpath, *freepath;
1033 int error, len;
1034
1035 switch (pfs->pfs_type) {
1036 case Pcurproc:
1037 if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc))
1038 return (EINVAL);
1039
f8c7a42d 1040 len = ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
984263bc
MD
1041
1042 return (uiomove(buf, len, ap->a_uio));
1043 /*
1044 * There _should_ be no way for an entire process to disappear
1045 * from under us...
1046 */
1047 case Pfile:
1048 procp = PFIND(pfs->pfs_pid);
41c20dac 1049 if (procp == NULL || procp->p_ucred == NULL) {
086c1d7e 1050 kprintf("procfs_readlink: pid %d disappeared\n",
984263bc
MD
1051 pfs->pfs_pid);
1052 return (uiomove("unknown", sizeof("unknown") - 1,
1053 ap->a_uio));
1054 }
541044dc 1055 error = vn_fullpath(procp, NULL, &fullpath, &freepath);
984263bc
MD
1056 if (error != 0)
1057 return (uiomove("unknown", sizeof("unknown") - 1,
1058 ap->a_uio));
1059 error = uiomove(fullpath, strlen(fullpath), ap->a_uio);
efda3bd0 1060 kfree(freepath, M_TEMP);
984263bc
MD
1061 return (error);
1062 default:
1063 return (EINVAL);
1064 }
1065}
1066
1067/*
1068 * convert decimal ascii to pid_t
1069 */
1070static pid_t
ac424f9b 1071atopid(const char *b, u_int len)
984263bc
MD
1072{
1073 pid_t p = 0;
1074
1075 while (len--) {
1076 char c = *b++;
1077 if (c < '0' || c > '9')
1078 return (NO_PID);
1079 p = 10 * p + (c - '0');
1080 if (p > PID_MAX)
1081 return (NO_PID);
1082 }
1083
1084 return (p);
1085}
1086