Adjust some comments with reality.
[dragonfly.git] / sys / vfs / procfs / procfs_vnops.c
CommitLineData
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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 $
b478fdce 40 * $DragonFly: src/sys/vfs/procfs/procfs_vnops.c,v 1.44 2007/08/08 00:12:52 swildner 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 *
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165 * procfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred,
166 * struct file *a_fp)
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167 */
168static int
ac424f9b 169procfs_open(struct vop_open_args *ap)
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170{
171 struct pfsnode *pfs = VTOPFS(ap->a_vp);
172 struct proc *p1, *p2;
173
174 p2 = PFIND(pfs->pfs_pid);
175 if (p2 == NULL)
176 return (ENOENT);
41c20dac 177 if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred))
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178 return (ENOENT);
179
180 switch (pfs->pfs_type) {
181 case Pmem:
182 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) ||
183 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE)))
184 return (EBUSY);
185
87de5057 186 p1 = curproc;
dadab5e9 187 KKASSERT(p1);
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188 /* Can't trace a process that's currently exec'ing. */
189 if ((p2->p_flag & P_INEXEC) != 0)
190 return EAGAIN;
41c20dac 191 if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred))
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192 return (EPERM);
193
194 if (ap->a_mode & FWRITE)
195 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL);
196
8ddc6004 197 break;
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198
199 default:
200 break;
201 }
202
8ddc6004 203 return (vop_stdopen(ap));
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204}
205
206/*
207 * close the pfsnode (vp) after doing i/o.
208 * (vp) is not locked on entry or exit.
209 *
210 * nothing to do for procfs other than undo
211 * any exclusive open flag (see _open above).
ac424f9b 212 *
87de5057 213 * procfs_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred)
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214 */
215static int
ac424f9b 216procfs_close(struct vop_close_args *ap)
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217{
218 struct pfsnode *pfs = VTOPFS(ap->a_vp);
219 struct proc *p;
220
221 switch (pfs->pfs_type) {
222 case Pmem:
223 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL))
224 pfs->pfs_flags &= ~(FWRITE|O_EXCL);
225 /*
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226 * v_opencount determines the last real close on the vnode.
227 *
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228 * If this is the last close, then it checks to see if
229 * the target process has PF_LINGER set in p_pfsflags,
230 * if this is *not* the case, then the process' stop flags
231 * are cleared, and the process is woken up. This is
232 * to help prevent the case where a process has been
233 * told to stop on an event, but then the requesting process
234 * has gone away or forgotten about it.
235 */
3c37c940 236 if ((ap->a_vp->v_opencount < 2)
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237 && (p = pfind(pfs->pfs_pid))
238 && !(p->p_pfsflags & PF_LINGER)) {
239 p->p_stops = 0;
240 p->p_step = 0;
241 wakeup(&p->p_step);
242 }
243 break;
244 default:
245 break;
246 }
247
8ddc6004 248 return (vop_stdclose(ap));
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249}
250
251/*
252 * do an ioctl operation on a pfsnode (vp).
253 * (vp) is not locked on entry or exit.
254 */
255static int
ac424f9b 256procfs_ioctl(struct vop_ioctl_args *ap)
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257{
258 struct pfsnode *pfs = VTOPFS(ap->a_vp);
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259 struct proc *procp;
260 struct proc *p;
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261 int error;
262 int signo;
263 struct procfs_status *psp;
264 unsigned char flags;
265
984263bc 266 procp = pfind(pfs->pfs_pid);
dadab5e9 267 if (procp == NULL)
984263bc 268 return ENOTTY;
87de5057 269 p = curproc;
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270 if (p == NULL)
271 return EINVAL;
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272
273 /* Can't trace a process that's currently exec'ing. */
274 if ((procp->p_flag & P_INEXEC) != 0)
275 return EAGAIN;
41c20dac 276 if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred))
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277 return EPERM;
278
279 switch (ap->a_command) {
280 case PIOCBIS:
281 procp->p_stops |= *(unsigned int*)ap->a_data;
282 break;
283 case PIOCBIC:
284 procp->p_stops &= ~*(unsigned int*)ap->a_data;
285 break;
286 case PIOCSFL:
287 /*
288 * NFLAGS is "non-suser_xxx flags" -- currently, only
289 * PFS_ISUGID ("ignore set u/g id");
290 */
291#define NFLAGS (PF_ISUGID)
292 flags = (unsigned char)*(unsigned int*)ap->a_data;
dadab5e9 293 if (flags & NFLAGS && (error = suser_cred(ap->a_cred, 0)))
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294 return error;
295 procp->p_pfsflags = flags;
296 break;
297 case PIOCGFL:
298 *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags;
299 break;
300 case PIOCSTATUS:
301 psp = (struct procfs_status *)ap->a_data;
302 psp->state = (procp->p_step == 0);
303 psp->flags = procp->p_pfsflags;
304 psp->events = procp->p_stops;
305 if (procp->p_step) {
306 psp->why = procp->p_stype;
307 psp->val = procp->p_xstat;
308 } else {
309 psp->why = psp->val = 0; /* Not defined values */
310 }
311 break;
312 case PIOCWAIT:
313 psp = (struct procfs_status *)ap->a_data;
314 if (procp->p_step == 0) {
377d4740 315 error = tsleep(&procp->p_stype, PCATCH, "piocwait", 0);
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316 if (error)
317 return error;
318 }
319 psp->state = 1; /* It stopped */
320 psp->flags = procp->p_pfsflags;
321 psp->events = procp->p_stops;
322 psp->why = procp->p_stype; /* why it stopped */
323 psp->val = procp->p_xstat; /* any extra info */
324 break;
325 case PIOCCONT: /* Restart a proc */
326 if (procp->p_step == 0)
327 return EINVAL; /* Can only start a stopped process */
328 if ((signo = *(int*)ap->a_data) != 0) {
329 if (signo >= NSIG || signo <= 0)
330 return EINVAL;
84204577 331 ksignal(procp, signo);
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332 }
333 procp->p_step = 0;
334 wakeup(&procp->p_step);
335 break;
336 default:
337 return (ENOTTY);
338 }
339 return 0;
340}
341
342/*
343 * do block mapping for pfsnode (vp).
344 * since we don't use the buffer cache
345 * for procfs this function should never
346 * be called. in any case, it's not clear
347 * what part of the kernel ever makes use
348 * of this function. for sanity, this is the
349 * usual no-op bmap, although returning
350 * (EIO) would be a reasonable alternative.
ac424f9b 351 *
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352 * procfs_bmap(struct vnode *a_vp, off_t a_loffset, struct vnode **a_vpp,
353 * off_t *a_doffsetp, int *a_runp)
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354 */
355static int
ac424f9b 356procfs_bmap(struct vop_bmap_args *ap)
984263bc 357{
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358 if (ap->a_vpp != NULL)
359 *ap->a_vpp = ap->a_vp;
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360 if (ap->a_doffsetp != NULL)
361 *ap->a_doffsetp = ap->a_loffset;
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362 if (ap->a_runp != NULL)
363 *ap->a_runp = 0;
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MD
364 if (ap->a_runb != NULL)
365 *ap->a_runb = 0;
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366 return (0);
367}
368
369/*
370 * procfs_inactive is called when the pfsnode
371 * is vrele'd and the reference count goes
372 * to zero. (vp) will be on the vnode free
373 * list, so to get it back vget() must be
374 * used.
375 *
376 * (vp) is locked on entry, but must be unlocked on exit.
ac424f9b 377 *
b478fdce 378 * procfs_inactive(struct vnode *a_vp)
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379 */
380static int
ac424f9b 381procfs_inactive(struct vop_inactive_args *ap)
984263bc 382{
5fd012e0 383 /*struct vnode *vp = ap->a_vp;*/
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384
385 return (0);
386}
387
388/*
389 * _reclaim is called when getnewvnode()
390 * wants to make use of an entry on the vnode
391 * free list. at this time the filesystem needs
392 * to free any private data and remove the node
393 * from any private lists.
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394 *
395 * procfs_reclaim(struct vnode *a_vp)
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396 */
397static int
ac424f9b 398procfs_reclaim(struct vop_reclaim_args *ap)
984263bc 399{
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400 return (procfs_freevp(ap->a_vp));
401}
402
403/*
404 * _print is used for debugging.
405 * just print a readable description
406 * of (vp).
ac424f9b
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407 *
408 * procfs_print(struct vnode *a_vp)
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409 */
410static int
ac424f9b 411procfs_print(struct vop_print_args *ap)
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412{
413 struct pfsnode *pfs = VTOPFS(ap->a_vp);
414
086c1d7e 415 kprintf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n",
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416 pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags);
417 return (0);
418}
419
420/*
421 * generic entry point for unsupported operations
422 */
423static int
66a1ddf5 424procfs_badop(struct vop_generic_args *ap)
984263bc 425{
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426 return (EIO);
427}
428
429/*
430 * Invent attributes for pfsnode (vp) and store
431 * them in (vap).
432 * Directories lengths are returned as zero since
433 * any real length would require the genuine size
434 * to be computed, and nothing cares anyway.
435 *
436 * this is relatively minimal for procfs.
ac424f9b 437 *
b478fdce 438 * procfs_getattr(struct vnode *a_vp, struct vattr *a_vap)
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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,
b478fdce 607 * struct ucred *a_cred)
ac424f9b 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 639 *
b478fdce 640 * procfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred)
984263bc
MD
641 */
642static int
ac424f9b 643procfs_access(struct vop_access_args *ap)
984263bc
MD
644{
645 struct vattr *vap;
646 struct vattr vattr;
647 int error;
648
649 /*
650 * If you're the super-user,
651 * you always get access.
652 */
653 if (ap->a_cred->cr_uid == 0)
654 return (0);
655
656 vap = &vattr;
87de5057 657 error = VOP_GETATTR(ap->a_vp, vap);
984263bc
MD
658 if (error)
659 return (error);
660
661 /*
662 * Access check is based on only one of owner, group, public.
663 * If not owner, then check group. If not a member of the
664 * group, then check public access.
665 */
666 if (ap->a_cred->cr_uid != vap->va_uid) {
667 gid_t *gp;
668 int i;
669
670 ap->a_mode >>= 3;
671 gp = ap->a_cred->cr_groups;
672 for (i = 0; i < ap->a_cred->cr_ngroups; i++, gp++)
673 if (vap->va_gid == *gp)
674 goto found;
675 ap->a_mode >>= 3;
676found:
677 ;
678 }
679
680 if ((vap->va_mode & ap->a_mode) == ap->a_mode)
681 return (0);
682
683 return (EACCES);
684}
685
686/*
3446c007
MD
687 * lookup. this is incredibly complicated in the general case, however
688 * for most pseudo-filesystems very little needs to be done.
ac424f9b
CP
689 *
690 * procfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
691 * struct componentname *a_cnp)
984263bc
MD
692 */
693static int
e62afb5f 694procfs_lookup(struct vop_old_lookup_args *ap)
984263bc
MD
695{
696 struct componentname *cnp = ap->a_cnp;
697 struct vnode **vpp = ap->a_vpp;
698 struct vnode *dvp = ap->a_dvp;
699 char *pname = cnp->cn_nameptr;
700 /* struct proc *curp = cnp->cn_proc; */
701 struct proc_target *pt;
702 pid_t pid;
703 struct pfsnode *pfs;
704 struct proc *p;
c7e98b2f 705 struct lwp *lp;
984263bc 706 int i;
3446c007 707 int error;
984263bc
MD
708
709 *vpp = NULL;
710
2b69e610 711 if (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME)
984263bc
MD
712 return (EROFS);
713
3446c007 714 error = 0;
984263bc
MD
715 if (cnp->cn_namelen == 1 && *pname == '.') {
716 *vpp = dvp;
3446c007
MD
717 vref(*vpp);
718 goto out;
984263bc
MD
719 }
720
721 pfs = VTOPFS(dvp);
722 switch (pfs->pfs_type) {
723 case Proot:
2b69e610 724 if (cnp->cn_flags & CNP_ISDOTDOT)
984263bc
MD
725 return (EIO);
726
3446c007
MD
727 if (CNEQ(cnp, "curproc", 7)) {
728 error = procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc);
729 goto out;
730 }
984263bc
MD
731
732 pid = atopid(pname, cnp->cn_namelen);
733 if (pid == NO_PID)
734 break;
735
736 p = PFIND(pid);
737 if (p == NULL)
738 break;
739
dcab9ef0
JS
740 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred))
741 break;
742
28c57d20
HP
743 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 &&
744 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid)
745 break;
746
3446c007
MD
747 error = procfs_allocvp(dvp->v_mount, vpp, pid, Pproc);
748 goto out;
984263bc
MD
749
750 case Pproc:
3446c007
MD
751 if (cnp->cn_flags & CNP_ISDOTDOT) {
752 error = procfs_root(dvp->v_mount, vpp);
753 goto out;
754 }
984263bc
MD
755
756 p = PFIND(pfs->pfs_pid);
757 if (p == NULL)
758 break;
c7e98b2f
SS
759 /* XXX lwp */
760 lp = FIRST_LWP_IN_PROC(p);
984263bc 761
dcab9ef0
JS
762 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred))
763 break;
764
28c57d20
HP
765 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 &&
766 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid)
767 break;
768
984263bc
MD
769 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) {
770 if (cnp->cn_namelen == pt->pt_namlen &&
771 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 &&
c7e98b2f 772 (pt->pt_valid == NULL || (*pt->pt_valid)(lp)))
984263bc
MD
773 goto found;
774 }
775 break;
776 found:
3446c007
MD
777 error = procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid,
778 pt->pt_pfstype);
779 goto out;
984263bc
MD
780
781 default:
3446c007
MD
782 error = ENOTDIR;
783 goto out;
984263bc 784 }
3446c007
MD
785 if (cnp->cn_nameiop == NAMEI_LOOKUP)
786 error = ENOENT;
787 else
788 error = EROFS;
789 /*
790 * If no error occured *vpp will hold a referenced locked vnode.
aa723195
MD
791 * dvp was passed to us locked and *vpp must be returned locked.
792 * If *vpp != dvp then we should unlock dvp if (1) this is not the
793 * last component or (2) CNP_LOCKPARENT is not set.
3446c007
MD
794 */
795out:
aa723195
MD
796 if (error == 0 && *vpp != dvp) {
797 if ((cnp->cn_flags & CNP_LOCKPARENT) == 0) {
798 cnp->cn_flags |= CNP_PDIRUNLOCK;
a11aaa81 799 vn_unlock(dvp);
3446c007
MD
800 }
801 }
802 return (error);
984263bc
MD
803}
804
805/*
806 * Does this process have a text file?
807 */
4d4fb029 808int
c7e98b2f 809procfs_validfile(struct lwp *lp)
984263bc 810{
c7e98b2f 811 return (procfs_findtextvp(lp->lwp_proc) != NULLVP);
984263bc
MD
812}
813
814/*
815 * readdir() returns directory entries from pfsnode (vp).
816 *
817 * We generate just one directory entry at a time, as it would probably
818 * not pay off to buffer several entries locally to save uiomove calls.
ac424f9b
CP
819 *
820 * procfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred,
821 * int *a_eofflag, int *a_ncookies, u_long **a_cookies)
984263bc
MD
822 */
823static int
ac424f9b 824procfs_readdir(struct vop_readdir_args *ap)
984263bc 825{
984263bc 826 struct pfsnode *pfs;
dcab9ef0 827 int error;
984263bc 828
dcab9ef0 829 if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX)
984263bc 830 return (EINVAL);
885ecb13
MD
831 if ((error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY)) != 0)
832 return (error);
dcab9ef0 833 pfs = VTOPFS(ap->a_vp);
984263bc
MD
834
835 switch (pfs->pfs_type) {
dcab9ef0 836 case Pproc:
885ecb13
MD
837 /*
838 * this is for the process-specific sub-directories.
839 * all that is needed to is copy out all the entries
840 * from the procent[] table (top of this file).
841 */
dcab9ef0
JS
842 error = procfs_readdir_proc(ap);
843 break;
dcab9ef0 844 case Proot:
885ecb13
MD
845 /*
846 * this is for the root of the procfs filesystem
847 * what is needed is a special entry for "curproc"
848 * followed by an entry for each process on allproc
849 */
dcab9ef0 850 error = procfs_readdir_root(ap);
984263bc 851 break;
984263bc
MD
852 default:
853 error = ENOTDIR;
854 break;
855 }
856
885ecb13 857 vn_unlock(ap->a_vp);
984263bc
MD
858 return (error);
859}
860
dcab9ef0
JS
861static int
862procfs_readdir_proc(struct vop_readdir_args *ap)
863{
864 struct pfsnode *pfs;
865 int error, i, retval;
866 struct proc *p;
c7e98b2f 867 struct lwp *lp;
dcab9ef0
JS
868 struct proc_target *pt;
869 struct uio *uio = ap->a_uio;
870
871 pfs = VTOPFS(ap->a_vp);
872 p = PFIND(pfs->pfs_pid);
873 if (p == NULL)
874 return(0);
875 if (!PRISON_CHECK(ap->a_cred, p->p_ucred))
876 return(0);
c7e98b2f
SS
877 /* XXX lwp */
878 lp = FIRST_LWP_IN_PROC(p);
dcab9ef0
JS
879
880 error = 0;
fb0466c9
MD
881 i = (int)uio->uio_offset;
882 if (i < 0)
883 return (EINVAL);
dcab9ef0
JS
884
885 for (pt = &proc_targets[i];
886 !error && uio->uio_resid > 0 && i < nproc_targets; pt++, i++) {
c7e98b2f 887 if (pt->pt_valid && (*pt->pt_valid)(lp) == 0)
dcab9ef0
JS
888 continue;
889
890 retval = vop_write_dirent(&error, uio,
891 PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype), pt->pt_type,
892 pt->pt_namlen, pt->pt_name);
893 if (retval)
894 break;
895 }
896
fb0466c9 897 uio->uio_offset = (off_t)i;
dcab9ef0
JS
898
899 return(0);
900}
901
51e64ff2
MD
902struct procfs_readdir_root_info {
903 int error;
904 int i;
905 int pcnt;
906 struct uio *uio;
907 struct ucred *cred;
908};
909
910static int procfs_readdir_root_callback(struct proc *p, void *data);
911
dcab9ef0
JS
912static int
913procfs_readdir_root(struct vop_readdir_args *ap)
914{
51e64ff2 915 struct procfs_readdir_root_info info;
dcab9ef0 916 struct uio *uio = ap->a_uio;
51e64ff2
MD
917 int res;
918
919 info.error = 0;
fb0466c9
MD
920 info.i = (int)uio->uio_offset;
921
922 if (info.i < 0)
923 return (EINVAL);
924
51e64ff2
MD
925 info.pcnt = 0;
926 info.uio = uio;
927 info.cred = ap->a_cred;
51e64ff2
MD
928 while (info.pcnt < 3) {
929 res = procfs_readdir_root_callback(NULL, &info);
930 if (res < 0)
931 break;
932 }
933 if (res >= 0)
934 allproc_scan(procfs_readdir_root_callback, &info);
fb0466c9 935 uio->uio_offset = (off_t)info.i;
51e64ff2
MD
936
937 return (info.error);
938}
939
940static int
941procfs_readdir_root_callback(struct proc *p, void *data)
942{
943 struct procfs_readdir_root_info *info = data;
944 struct uio *uio;
945 int retval;
dcab9ef0
JS
946 ino_t d_ino;
947 const char *d_name;
948 char d_name_pid[20];
949 size_t d_namlen;
950 uint8_t d_type;
951
51e64ff2 952 uio = info->uio;
dcab9ef0 953
51e64ff2
MD
954 if (uio->uio_resid <= 0 || info->error)
955 return(-1);
dcab9ef0 956
51e64ff2
MD
957 switch (info->pcnt) {
958 case 0: /* `.' */
959 d_ino = PROCFS_FILENO(0, Proot);
960 d_name = ".";
961 d_namlen = 1;
962 d_type = DT_DIR;
963 break;
964 case 1: /* `..' */
965 d_ino = PROCFS_FILENO(0, Proot);
966 d_name = "..";
967 d_namlen = 2;
968 d_type = DT_DIR;
969 break;
dcab9ef0 970
51e64ff2
MD
971 case 2:
972 d_ino = PROCFS_FILENO(0, Pcurproc);
973 d_namlen = 7;
974 d_name = "curproc";
975 d_type = DT_LNK;
976 break;
dcab9ef0 977
51e64ff2
MD
978
979 default:
980 if (!PRISON_CHECK(info->cred, p->p_ucred))
981 return(0);
982 if (ps_showallprocs == 0 &&
983 info->cred->cr_uid != 0 &&
984 info->cred->cr_uid != p->p_ucred->cr_uid) {
985 return(0);
dcab9ef0
JS
986 }
987
51e64ff2
MD
988 /*
989 * Skip entries we have already returned (optimization)
990 */
991 if (info->pcnt < info->i) {
992 ++info->pcnt;
993 return(0);
994 }
995
996 d_ino = PROCFS_FILENO(p->p_pid, Pproc);
f8c7a42d 997 d_namlen = ksnprintf(d_name_pid, sizeof(d_name_pid),
51e64ff2
MD
998 "%ld", (long)p->p_pid);
999 d_name = d_name_pid;
1000 d_type = DT_DIR;
1001 break;
dcab9ef0 1002 }
51e64ff2
MD
1003
1004 /*
1005 * Skip entries we have already returned (optimization)
1006 */
1007 if (info->pcnt < info->i) {
1008 ++info->pcnt;
1009 return(0);
1010 }
1011
1012 retval = vop_write_dirent(&info->error, uio,
1013 d_ino, d_type, d_namlen, d_name);
1014 if (retval)
1015 return(-1);
1016 ++info->pcnt;
1017 ++info->i;
dcab9ef0
JS
1018 return(0);
1019}
1020
984263bc
MD
1021/*
1022 * readlink reads the link of `curproc' or `file'
1023 */
1024static int
ac424f9b 1025procfs_readlink(struct vop_readlink_args *ap)
984263bc
MD
1026{
1027 char buf[16]; /* should be enough */
1028 struct proc *procp;
1029 struct vnode *vp = ap->a_vp;
1030 struct pfsnode *pfs = VTOPFS(vp);
1031 char *fullpath, *freepath;
1032 int error, len;
1033
1034 switch (pfs->pfs_type) {
1035 case Pcurproc:
1036 if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc))
1037 return (EINVAL);
1038
f8c7a42d 1039 len = ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid);
984263bc
MD
1040
1041 return (uiomove(buf, len, ap->a_uio));
1042 /*
1043 * There _should_ be no way for an entire process to disappear
1044 * from under us...
1045 */
1046 case Pfile:
1047 procp = PFIND(pfs->pfs_pid);
41c20dac 1048 if (procp == NULL || procp->p_ucred == NULL) {
086c1d7e 1049 kprintf("procfs_readlink: pid %d disappeared\n",
984263bc
MD
1050 pfs->pfs_pid);
1051 return (uiomove("unknown", sizeof("unknown") - 1,
1052 ap->a_uio));
1053 }
541044dc 1054 error = vn_fullpath(procp, NULL, &fullpath, &freepath);
984263bc
MD
1055 if (error != 0)
1056 return (uiomove("unknown", sizeof("unknown") - 1,
1057 ap->a_uio));
1058 error = uiomove(fullpath, strlen(fullpath), ap->a_uio);
efda3bd0 1059 kfree(freepath, M_TEMP);
984263bc
MD
1060 return (error);
1061 default:
1062 return (EINVAL);
1063 }
1064}
1065
1066/*
1067 * convert decimal ascii to pid_t
1068 */
1069static pid_t
ac424f9b 1070atopid(const char *b, u_int len)
984263bc
MD
1071{
1072 pid_t p = 0;
1073
1074 while (len--) {
1075 char c = *b++;
1076 if (c < '0' || c > '9')
1077 return (NO_PID);
1078 p = 10 * p + (c - '0');
1079 if (p > PID_MAX)
1080 return (NO_PID);
1081 }
1082
1083 return (p);
1084}
1085