procfs_subr.c revision 1.66 1 /* $NetBSD: procfs_subr.c,v 1.66 2005/10/01 03:17:37 atatat Exp $ */
2
3 /*
4 * Copyright (c) 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Jan-Simon Pendry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95
35 */
36
37 /*
38 * Copyright (c) 1994 Christopher G. Demetriou. All rights reserved.
39 * Copyright (c) 1993 Jan-Simon Pendry
40 *
41 * This code is derived from software contributed to Berkeley by
42 * Jan-Simon Pendry.
43 *
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
46 * are met:
47 * 1. Redistributions of source code must retain the above copyright
48 * notice, this list of conditions and the following disclaimer.
49 * 2. Redistributions in binary form must reproduce the above copyright
50 * notice, this list of conditions and the following disclaimer in the
51 * documentation and/or other materials provided with the distribution.
52 * 3. All advertising materials mentioning features or use of this software
53 * must display the following acknowledgement:
54 * This product includes software developed by the University of
55 * California, Berkeley and its contributors.
56 * 4. Neither the name of the University nor the names of its contributors
57 * may be used to endorse or promote products derived from this software
58 * without specific prior written permission.
59 *
60 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70 * SUCH DAMAGE.
71 *
72 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95
73 */
74
75 #include <sys/cdefs.h>
76 __KERNEL_RCSID(0, "$NetBSD: procfs_subr.c,v 1.66 2005/10/01 03:17:37 atatat Exp $");
77
78 #include <sys/param.h>
79 #include <sys/systm.h>
80 #include <sys/time.h>
81 #include <sys/kernel.h>
82 #include <sys/proc.h>
83 #include <sys/vnode.h>
84 #include <sys/malloc.h>
85 #include <sys/stat.h>
86 #include <sys/file.h>
87 #include <sys/filedesc.h>
88
89 #include <miscfs/procfs/procfs.h>
90
91 void procfs_hashins(struct pfsnode *);
92 void procfs_hashrem(struct pfsnode *);
93 struct vnode *procfs_hashget(pid_t, pfstype, int, struct mount *);
94
95 LIST_HEAD(pfs_hashhead, pfsnode) *pfs_hashtbl;
96 u_long pfs_ihash; /* size of hash table - 1 */
97 #define PFSPIDHASH(pid) ((pid) & pfs_ihash)
98
99 struct lock pfs_hashlock;
100 struct simplelock pfs_hash_slock;
101
102 #define ISSET(t, f) ((t) & (f))
103
104 /*
105 * allocate a pfsnode/vnode pair. the vnode is
106 * referenced, and locked.
107 *
108 * the pid, pfs_type, and mount point uniquely
109 * identify a pfsnode. the mount point is needed
110 * because someone might mount this filesystem
111 * twice.
112 *
113 * all pfsnodes are maintained on a singly-linked
114 * list. new nodes are only allocated when they cannot
115 * be found on this list. entries on the list are
116 * removed when the vfs reclaim entry is called.
117 *
118 * a single lock is kept for the entire list. this is
119 * needed because the getnewvnode() function can block
120 * waiting for a vnode to become free, in which case there
121 * may be more than one process trying to get the same
122 * vnode. this lock is only taken if we are going to
123 * call getnewvnode, since the kernel itself is single-threaded.
124 *
125 * if an entry is found on the list, then call vget() to
126 * take a reference. this is done because there may be
127 * zero references to it and so it needs to removed from
128 * the vnode free list.
129 */
130 int
131 procfs_allocvp(mp, vpp, pid, pfs_type, fd)
132 struct mount *mp;
133 struct vnode **vpp;
134 pid_t pid;
135 pfstype pfs_type;
136 int fd;
137 {
138 struct pfsnode *pfs;
139 struct vnode *vp;
140 int error;
141
142 do {
143 if ((*vpp = procfs_hashget(pid, pfs_type, fd, mp)) != NULL)
144 return (0);
145 } while (lockmgr(&pfs_hashlock, LK_EXCLUSIVE|LK_SLEEPFAIL, 0));
146
147 if ((error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, &vp)) != 0) {
148 *vpp = NULL;
149 lockmgr(&pfs_hashlock, LK_RELEASE, NULL);
150 return (error);
151 }
152
153 MALLOC(pfs, void *, sizeof(struct pfsnode), M_TEMP, M_WAITOK);
154 vp->v_data = pfs;
155
156 pfs->pfs_pid = pid;
157 pfs->pfs_type = pfs_type;
158 pfs->pfs_vnode = vp;
159 pfs->pfs_flags = 0;
160 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type, fd);
161 pfs->pfs_fd = fd;
162
163 switch (pfs_type) {
164 case PFSroot: /* /proc = dr-xr-xr-x */
165 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
166 vp->v_type = VDIR;
167 vp->v_flag = VROOT;
168 break;
169
170 case PFScurproc: /* /proc/curproc = lr-xr-xr-x */
171 case PFSself: /* /proc/self = lr-xr-xr-x */
172 case PFScwd: /* /proc/N/cwd = lr-xr-xr-x */
173 case PFSchroot: /* /proc/N/chroot = lr-xr-xr-x */
174 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
175 vp->v_type = VLNK;
176 break;
177
178 case PFSproc: /* /proc/N = dr-xr-xr-x */
179 case PFSfd:
180 if (fd == -1) { /* /proc/N/fd = dr-xr-xr-x */
181 pfs->pfs_mode = S_IRUSR|S_IXUSR;
182 vp->v_type = VDIR;
183 } else { /* /proc/N/fd/M = [ps-]rw------- */
184 struct file *fp;
185 struct vnode *vxp;
186 struct proc *pown;
187
188 /* XXX can procfs_getfp() ever fail here? */
189 if ((error = procfs_getfp(pfs, &pown, &fp)) != 0)
190 goto bad;
191 FILE_USE(fp);
192
193 pfs->pfs_mode = S_IRUSR|S_IWUSR;
194 switch (fp->f_type) {
195 case DTYPE_VNODE:
196 vxp = (struct vnode *)fp->f_data;
197
198 /*
199 * We make symlinks for directories
200 * to avoid cycles.
201 */
202 if (vxp->v_type == VDIR)
203 goto symlink;
204 vp->v_type = vxp->v_type;
205 break;
206 case DTYPE_PIPE:
207 vp->v_type = VFIFO;
208 break;
209 case DTYPE_SOCKET:
210 vp->v_type = VSOCK;
211 break;
212 case DTYPE_KQUEUE:
213 case DTYPE_MISC:
214 symlink:
215 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|
216 S_IXGRP|S_IROTH|S_IXOTH;
217 vp->v_type = VLNK;
218 break;
219 default:
220 error = EOPNOTSUPP;
221 FILE_UNUSE(fp, pown);
222 goto bad;
223 }
224 FILE_UNUSE(fp, pown);
225 }
226 break;
227
228 case PFSfile: /* /proc/N/file = -rw------- */
229 case PFSmem: /* /proc/N/mem = -rw------- */
230 case PFSregs: /* /proc/N/regs = -rw------- */
231 case PFSfpregs: /* /proc/N/fpregs = -rw------- */
232 pfs->pfs_mode = S_IRUSR|S_IWUSR;
233 vp->v_type = VREG;
234 break;
235
236 case PFSctl: /* /proc/N/ctl = --w------ */
237 case PFSnote: /* /proc/N/note = --w------ */
238 case PFSnotepg: /* /proc/N/notepg = --w------ */
239 pfs->pfs_mode = S_IWUSR;
240 vp->v_type = VREG;
241 break;
242
243 case PFSmap: /* /proc/N/map = -r--r--r-- */
244 case PFSmaps: /* /proc/N/maps = -r--r--r-- */
245 case PFSstatus: /* /proc/N/status = -r--r--r-- */
246 case PFSstat: /* /proc/N/stat = -r--r--r-- */
247 case PFScmdline: /* /proc/N/cmdline = -r--r--r-- */
248 case PFSmeminfo: /* /proc/meminfo = -r--r--r-- */
249 case PFScpuinfo: /* /proc/cpuinfo = -r--r--r-- */
250 case PFSuptime: /* /proc/uptime = -r--r--r-- */
251 case PFSmounts: /* /proc/mounts = -r--r--r-- */
252 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH;
253 vp->v_type = VREG;
254 break;
255
256 #ifdef __HAVE_PROCFS_MACHDEP
257 PROCFS_MACHDEP_NODETYPE_CASES
258 procfs_machdep_allocvp(vp);
259 break;
260 #endif
261
262 default:
263 panic("procfs_allocvp");
264 }
265
266 procfs_hashins(pfs);
267 uvm_vnp_setsize(vp, 0);
268 lockmgr(&pfs_hashlock, LK_RELEASE, NULL);
269
270 *vpp = vp;
271 return (0);
272
273 bad:
274 lockmgr(&pfs_hashlock, LK_RELEASE, NULL);
275 FREE(pfs, M_TEMP);
276 ungetnewvnode(vp);
277 return (error);
278 }
279
280 int
281 procfs_freevp(vp)
282 struct vnode *vp;
283 {
284 struct pfsnode *pfs = VTOPFS(vp);
285
286 procfs_hashrem(pfs);
287
288 FREE(vp->v_data, M_TEMP);
289 vp->v_data = 0;
290 return (0);
291 }
292
293 int
294 procfs_rw(v)
295 void *v;
296 {
297 struct vop_read_args *ap = v;
298 struct vnode *vp = ap->a_vp;
299 struct uio *uio = ap->a_uio;
300 struct proc *curp = uio->uio_procp;
301 struct pfsnode *pfs = VTOPFS(vp);
302 struct lwp *l;
303 struct proc *p;
304
305 if (uio->uio_offset < 0)
306 return EINVAL;
307 p = PFIND(pfs->pfs_pid);
308 if (p == 0)
309 return ESRCH;
310 /*
311 * Do not allow init to be modified while in secure mode; it
312 * could be duped into changing the security level.
313 */
314 if (uio->uio_rw == UIO_WRITE && p == initproc && securelevel > -1)
315 return EPERM;
316
317 /* XXX NJWLWP
318 * The entire procfs interface needs work to be useful to
319 * a process with multiple LWPs. For the moment, we'll
320 * just kluge this and fail on others.
321 */
322 l = proc_representative_lwp(p);
323
324 switch (pfs->pfs_type) {
325 case PFSnote:
326 case PFSnotepg:
327 return (procfs_donote(curp, p, pfs, uio));
328
329 case PFSregs:
330 return (procfs_doregs(curp, l, pfs, uio));
331
332 case PFSfpregs:
333 return (procfs_dofpregs(curp, l, pfs, uio));
334
335 case PFSctl:
336 return (procfs_doctl(curp, l, pfs, uio));
337
338 case PFSstatus:
339 return (procfs_dostatus(curp, l, pfs, uio));
340
341 case PFSstat:
342 return (procfs_do_pid_stat(curp, l, pfs, uio));
343
344 case PFSmap:
345 return (procfs_domap(curp, p, pfs, uio, 0));
346
347 case PFSmaps:
348 return (procfs_domap(curp, p, pfs, uio, 1));
349
350 case PFSmem:
351 return (procfs_domem(curp, p, pfs, uio));
352
353 case PFScmdline:
354 return (procfs_docmdline(curp, p, pfs, uio));
355
356 case PFSmeminfo:
357 return (procfs_domeminfo(curp, p, pfs, uio));
358
359 case PFScpuinfo:
360 return (procfs_docpuinfo(curp, p, pfs, uio));
361
362 case PFSfd:
363 return (procfs_dofd(curp, p, pfs, uio));
364
365 case PFSuptime:
366 return (procfs_douptime(curp, p, pfs, uio));
367
368 case PFSmounts:
369 return (procfs_domounts(curp, p, pfs, uio));
370
371 #ifdef __HAVE_PROCFS_MACHDEP
372 PROCFS_MACHDEP_NODETYPE_CASES
373 return (procfs_machdep_rw(curp, l, pfs, uio));
374 #endif
375
376 default:
377 return (EOPNOTSUPP);
378 }
379 }
380
381 /*
382 * Get a string from userland into (bf). Strip a trailing
383 * nl character (to allow easy access from the shell).
384 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr
385 * will automatically add a nul char at the end.
386 *
387 * Returns 0 on success or the following errors
388 *
389 * EINVAL: file offset is non-zero.
390 * EMSGSIZE: message is longer than kernel buffer
391 * EFAULT: user i/o buffer is not addressable
392 */
393 int
394 vfs_getuserstr(uio, bf, buflenp)
395 struct uio *uio;
396 char *bf;
397 int *buflenp;
398 {
399 int xlen;
400 int error;
401
402 if (uio->uio_offset != 0)
403 return (EINVAL);
404
405 xlen = *buflenp;
406
407 /* must be able to read the whole string in one go */
408 if (xlen < uio->uio_resid)
409 return (EMSGSIZE);
410 xlen = uio->uio_resid;
411
412 if ((error = uiomove(bf, xlen, uio)) != 0)
413 return (error);
414
415 /* allow multiple writes without seeks */
416 uio->uio_offset = 0;
417
418 /* cleanup string and remove trailing newline */
419 bf[xlen] = '\0';
420 xlen = strlen(bf);
421 if (xlen > 0 && bf[xlen-1] == '\n')
422 bf[--xlen] = '\0';
423 *buflenp = xlen;
424
425 return (0);
426 }
427
428 const vfs_namemap_t *
429 vfs_findname(nm, bf, buflen)
430 const vfs_namemap_t *nm;
431 const char *bf;
432 int buflen;
433 {
434
435 for (; nm->nm_name; nm++)
436 if (memcmp(bf, nm->nm_name, buflen+1) == 0)
437 return (nm);
438
439 return (0);
440 }
441
442 /*
443 * Initialize pfsnode hash table.
444 */
445 void
446 procfs_hashinit()
447 {
448 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0);
449 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT,
450 M_WAITOK, &pfs_ihash);
451 simple_lock_init(&pfs_hash_slock);
452 }
453
454 void
455 procfs_hashreinit()
456 {
457 struct pfsnode *pp;
458 struct pfs_hashhead *oldhash, *hash;
459 u_long i, oldmask, mask, val;
460
461 hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK,
462 &mask);
463
464 simple_lock(&pfs_hash_slock);
465 oldhash = pfs_hashtbl;
466 oldmask = pfs_ihash;
467 pfs_hashtbl = hash;
468 pfs_ihash = mask;
469 for (i = 0; i <= oldmask; i++) {
470 while ((pp = LIST_FIRST(&oldhash[i])) != NULL) {
471 LIST_REMOVE(pp, pfs_hash);
472 val = PFSPIDHASH(pp->pfs_pid);
473 LIST_INSERT_HEAD(&hash[val], pp, pfs_hash);
474 }
475 }
476 simple_unlock(&pfs_hash_slock);
477 hashdone(oldhash, M_UFSMNT);
478 }
479
480 /*
481 * Free pfsnode hash table.
482 */
483 void
484 procfs_hashdone()
485 {
486 hashdone(pfs_hashtbl, M_UFSMNT);
487 }
488
489 struct vnode *
490 procfs_hashget(pid, type, fd, mp)
491 pid_t pid;
492 pfstype type;
493 int fd;
494 struct mount *mp;
495 {
496 struct pfs_hashhead *ppp;
497 struct pfsnode *pp;
498 struct vnode *vp;
499
500 loop:
501 simple_lock(&pfs_hash_slock);
502 ppp = &pfs_hashtbl[PFSPIDHASH(pid)];
503 LIST_FOREACH(pp, ppp, pfs_hash) {
504 vp = PFSTOV(pp);
505 if (pid == pp->pfs_pid && pp->pfs_type == type &&
506 pp->pfs_fd == fd && vp->v_mount == mp) {
507 simple_lock(&vp->v_interlock);
508 simple_unlock(&pfs_hash_slock);
509 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK))
510 goto loop;
511 return (vp);
512 }
513 }
514 simple_unlock(&pfs_hash_slock);
515 return (NULL);
516 }
517
518 /*
519 * Insert the pfsnode into the hash table and lock it.
520 */
521 void
522 procfs_hashins(pp)
523 struct pfsnode *pp;
524 {
525 struct pfs_hashhead *ppp;
526
527 /* lock the pfsnode, then put it on the appropriate hash list */
528 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0);
529
530 simple_lock(&pfs_hash_slock);
531 ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)];
532 LIST_INSERT_HEAD(ppp, pp, pfs_hash);
533 simple_unlock(&pfs_hash_slock);
534 }
535
536 /*
537 * Remove the pfsnode from the hash table.
538 */
539 void
540 procfs_hashrem(pp)
541 struct pfsnode *pp;
542 {
543 simple_lock(&pfs_hash_slock);
544 LIST_REMOVE(pp, pfs_hash);
545 simple_unlock(&pfs_hash_slock);
546 }
547
548 void
549 procfs_revoke_vnodes(p, arg)
550 struct proc *p;
551 void *arg;
552 {
553 struct pfsnode *pfs, *pnext;
554 struct vnode *vp;
555 struct mount *mp = (struct mount *)arg;
556 struct pfs_hashhead *ppp;
557
558 if (!(p->p_flag & P_SUGID))
559 return;
560
561 ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)];
562 for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) {
563 vp = PFSTOV(pfs);
564 pnext = LIST_NEXT(pfs, pfs_hash);
565 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid &&
566 vp->v_mount == mp)
567 VOP_REVOKE(vp, REVOKEALL);
568 }
569 }
570
571 int
572 procfs_getfp(pfs, pown, fp)
573 struct pfsnode *pfs;
574 struct proc **pown;
575 struct file **fp;
576 {
577 struct proc *p = PFIND(pfs->pfs_pid);
578
579 if (p == NULL)
580 return ESRCH;
581
582 if (pfs->pfs_fd == -1)
583 return EINVAL;
584
585 if ((*fp = fd_getfile(p->p_fd, pfs->pfs_fd)) == NULL)
586 return EBADF;
587
588 *pown = p;
589 return 0;
590 }
591