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 $ 40 * $DragonFly: src/sys/vfs/procfs/procfs_vnops.c,v 1.18 2004/08/17 18:57:35 dillon Exp $ 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> 61 #include <machine/reg.h> 62 #include <vm/vm_zone.h> 63 #include <vfs/procfs/procfs.h> 64 #include <sys/pioctl.h> 65 66 static int procfs_access (struct vop_access_args *); 67 static int procfs_badop (void); 68 static int procfs_bmap (struct vop_bmap_args *); 69 static int procfs_close (struct vop_close_args *); 70 static int procfs_getattr (struct vop_getattr_args *); 71 static int procfs_inactive (struct vop_inactive_args *); 72 static int procfs_ioctl (struct vop_ioctl_args *); 73 static int procfs_lookup (struct vop_lookup_args *); 74 static int procfs_open (struct vop_open_args *); 75 static int procfs_print (struct vop_print_args *); 76 static int procfs_readdir (struct vop_readdir_args *); 77 static int procfs_readlink (struct vop_readlink_args *); 78 static int procfs_reclaim (struct vop_reclaim_args *); 79 static int procfs_setattr (struct vop_setattr_args *); 80 81 /* 82 * This is a list of the valid names in the 83 * process-specific sub-directories. It is 84 * used in procfs_lookup and procfs_readdir 85 */ 86 static struct proc_target { 87 u_char pt_type; 88 u_char pt_namlen; 89 char *pt_name; 90 pfstype pt_pfstype; 91 int (*pt_valid) (struct proc *p); 92 } proc_targets[] = { 93 #define N(s) sizeof(s)-1, s 94 /* name type validp */ 95 { DT_DIR, N("."), Pproc, NULL }, 96 { DT_DIR, N(".."), Proot, NULL }, 97 { DT_REG, N("mem"), Pmem, NULL }, 98 { DT_REG, N("regs"), Pregs, procfs_validregs }, 99 { DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs }, 100 { DT_REG, N("dbregs"), Pdbregs, procfs_validdbregs }, 101 { DT_REG, N("ctl"), Pctl, NULL }, 102 { DT_REG, N("status"), Pstatus, NULL }, 103 { DT_REG, N("note"), Pnote, NULL }, 104 { DT_REG, N("notepg"), Pnotepg, NULL }, 105 { DT_REG, N("map"), Pmap, procfs_validmap }, 106 { DT_REG, N("etype"), Ptype, procfs_validtype }, 107 { DT_REG, N("cmdline"), Pcmdline, NULL }, 108 { DT_REG, N("rlimit"), Prlimit, NULL }, 109 { DT_LNK, N("file"), Pfile, NULL }, 110 #undef N 111 }; 112 static const int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]); 113 114 static pid_t atopid (const char *, u_int); 115 116 /* 117 * set things up for doing i/o on 118 * the pfsnode (vp). (vp) is locked 119 * on entry, and should be left locked 120 * on exit. 121 * 122 * for procfs we don't need to do anything 123 * in particular for i/o. all that is done 124 * is to support exclusive open on process 125 * memory images. 126 * 127 * procfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred, 128 * struct thread *a_td) 129 */ 130 static int 131 procfs_open(struct vop_open_args *ap) 132 { 133 struct pfsnode *pfs = VTOPFS(ap->a_vp); 134 struct proc *p1, *p2; 135 136 p2 = PFIND(pfs->pfs_pid); 137 if (p2 == NULL) 138 return (ENOENT); 139 if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred)) 140 return (ENOENT); 141 142 switch (pfs->pfs_type) { 143 case Pmem: 144 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) || 145 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) 146 return (EBUSY); 147 148 p1 = ap->a_td->td_proc; 149 KKASSERT(p1); 150 /* Can't trace a process that's currently exec'ing. */ 151 if ((p2->p_flag & P_INEXEC) != 0) 152 return EAGAIN; 153 if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred)) 154 return (EPERM); 155 156 if (ap->a_mode & FWRITE) 157 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL); 158 159 return (0); 160 161 default: 162 break; 163 } 164 165 return (0); 166 } 167 168 /* 169 * close the pfsnode (vp) after doing i/o. 170 * (vp) is not locked on entry or exit. 171 * 172 * nothing to do for procfs other than undo 173 * any exclusive open flag (see _open above). 174 * 175 * procfs_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred, 176 * struct thread *a_td) 177 */ 178 static int 179 procfs_close(struct vop_close_args *ap) 180 { 181 struct pfsnode *pfs = VTOPFS(ap->a_vp); 182 struct proc *p; 183 184 switch (pfs->pfs_type) { 185 case Pmem: 186 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL)) 187 pfs->pfs_flags &= ~(FWRITE|O_EXCL); 188 /* 189 * This rather complicated-looking code is trying to 190 * determine if this was the last close on this particular 191 * vnode. While one would expect v_usecount to be 1 at 192 * that point, it seems that (according to John Dyson) 193 * the VM system will bump up the usecount. So: if the 194 * usecount is 2, and VOBJBUF is set, then this is really 195 * the last close. Otherwise, if the usecount is < 2 196 * then it is definitely the last close. 197 * If this is the last close, then it checks to see if 198 * the target process has PF_LINGER set in p_pfsflags, 199 * if this is *not* the case, then the process' stop flags 200 * are cleared, and the process is woken up. This is 201 * to help prevent the case where a process has been 202 * told to stop on an event, but then the requesting process 203 * has gone away or forgotten about it. 204 */ 205 if ((ap->a_vp->v_usecount < 2) 206 && (p = pfind(pfs->pfs_pid)) 207 && !(p->p_pfsflags & PF_LINGER)) { 208 p->p_stops = 0; 209 p->p_step = 0; 210 wakeup(&p->p_step); 211 } 212 break; 213 default: 214 break; 215 } 216 217 return (0); 218 } 219 220 /* 221 * do an ioctl operation on a pfsnode (vp). 222 * (vp) is not locked on entry or exit. 223 */ 224 static int 225 procfs_ioctl(struct vop_ioctl_args *ap) 226 { 227 struct pfsnode *pfs = VTOPFS(ap->a_vp); 228 struct proc *procp; 229 struct proc *p; 230 int error; 231 int signo; 232 struct procfs_status *psp; 233 unsigned char flags; 234 235 procp = pfind(pfs->pfs_pid); 236 if (procp == NULL) 237 return ENOTTY; 238 p = ap->a_td->td_proc; 239 if (p == NULL) 240 return EINVAL; 241 242 /* Can't trace a process that's currently exec'ing. */ 243 if ((procp->p_flag & P_INEXEC) != 0) 244 return EAGAIN; 245 if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred)) 246 return EPERM; 247 248 switch (ap->a_command) { 249 case PIOCBIS: 250 procp->p_stops |= *(unsigned int*)ap->a_data; 251 break; 252 case PIOCBIC: 253 procp->p_stops &= ~*(unsigned int*)ap->a_data; 254 break; 255 case PIOCSFL: 256 /* 257 * NFLAGS is "non-suser_xxx flags" -- currently, only 258 * PFS_ISUGID ("ignore set u/g id"); 259 */ 260 #define NFLAGS (PF_ISUGID) 261 flags = (unsigned char)*(unsigned int*)ap->a_data; 262 if (flags & NFLAGS && (error = suser_cred(ap->a_cred, 0))) 263 return error; 264 procp->p_pfsflags = flags; 265 break; 266 case PIOCGFL: 267 *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags; 268 break; 269 case PIOCSTATUS: 270 psp = (struct procfs_status *)ap->a_data; 271 psp->state = (procp->p_step == 0); 272 psp->flags = procp->p_pfsflags; 273 psp->events = procp->p_stops; 274 if (procp->p_step) { 275 psp->why = procp->p_stype; 276 psp->val = procp->p_xstat; 277 } else { 278 psp->why = psp->val = 0; /* Not defined values */ 279 } 280 break; 281 case PIOCWAIT: 282 psp = (struct procfs_status *)ap->a_data; 283 if (procp->p_step == 0) { 284 error = tsleep(&procp->p_stype, PCATCH, "piocwait", 0); 285 if (error) 286 return error; 287 } 288 psp->state = 1; /* It stopped */ 289 psp->flags = procp->p_pfsflags; 290 psp->events = procp->p_stops; 291 psp->why = procp->p_stype; /* why it stopped */ 292 psp->val = procp->p_xstat; /* any extra info */ 293 break; 294 case PIOCCONT: /* Restart a proc */ 295 if (procp->p_step == 0) 296 return EINVAL; /* Can only start a stopped process */ 297 if ((signo = *(int*)ap->a_data) != 0) { 298 if (signo >= NSIG || signo <= 0) 299 return EINVAL; 300 psignal(procp, signo); 301 } 302 procp->p_step = 0; 303 wakeup(&procp->p_step); 304 break; 305 default: 306 return (ENOTTY); 307 } 308 return 0; 309 } 310 311 /* 312 * do block mapping for pfsnode (vp). 313 * since we don't use the buffer cache 314 * for procfs this function should never 315 * be called. in any case, it's not clear 316 * what part of the kernel ever makes use 317 * of this function. for sanity, this is the 318 * usual no-op bmap, although returning 319 * (EIO) would be a reasonable alternative. 320 * 321 * procfs_bmap(struct vnode *a_vp, daddr_t a_bn, struct vnode **a_vpp, 322 * daddr_t *a_bnp, int *a_runp) 323 */ 324 static int 325 procfs_bmap(struct vop_bmap_args *ap) 326 { 327 if (ap->a_vpp != NULL) 328 *ap->a_vpp = ap->a_vp; 329 if (ap->a_bnp != NULL) 330 *ap->a_bnp = ap->a_bn; 331 if (ap->a_runp != NULL) 332 *ap->a_runp = 0; 333 return (0); 334 } 335 336 /* 337 * procfs_inactive is called when the pfsnode 338 * is vrele'd and the reference count goes 339 * to zero. (vp) will be on the vnode free 340 * list, so to get it back vget() must be 341 * used. 342 * 343 * (vp) is locked on entry, but must be unlocked on exit. 344 * 345 * procfs_inactive(struct vnode *a_vp, struct thread *a_td) 346 */ 347 static int 348 procfs_inactive(struct vop_inactive_args *ap) 349 { 350 struct vnode *vp = ap->a_vp; 351 352 VOP_UNLOCK(vp, NULL, 0, ap->a_td); 353 354 return (0); 355 } 356 357 /* 358 * _reclaim is called when getnewvnode() 359 * wants to make use of an entry on the vnode 360 * free list. at this time the filesystem needs 361 * to free any private data and remove the node 362 * from any private lists. 363 * 364 * procfs_reclaim(struct vnode *a_vp) 365 */ 366 static int 367 procfs_reclaim(struct vop_reclaim_args *ap) 368 { 369 return (procfs_freevp(ap->a_vp)); 370 } 371 372 /* 373 * _print is used for debugging. 374 * just print a readable description 375 * of (vp). 376 * 377 * procfs_print(struct vnode *a_vp) 378 */ 379 static int 380 procfs_print(struct vop_print_args *ap) 381 { 382 struct pfsnode *pfs = VTOPFS(ap->a_vp); 383 384 printf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n", 385 pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags); 386 return (0); 387 } 388 389 /* 390 * generic entry point for unsupported operations 391 */ 392 static int 393 procfs_badop(void) 394 { 395 return (EIO); 396 } 397 398 /* 399 * Invent attributes for pfsnode (vp) and store 400 * them in (vap). 401 * Directories lengths are returned as zero since 402 * any real length would require the genuine size 403 * to be computed, and nothing cares anyway. 404 * 405 * this is relatively minimal for procfs. 406 * 407 * procfs_getattr(struct vnode *a_vp, struct vattr *a_vap, 408 * struct ucred *a_cred, struct thread *a_td) 409 */ 410 static int 411 procfs_getattr(struct vop_getattr_args *ap) 412 { 413 struct pfsnode *pfs = VTOPFS(ap->a_vp); 414 struct vattr *vap = ap->a_vap; 415 struct proc *procp; 416 int error; 417 418 /* 419 * First make sure that the process and its credentials 420 * still exist. 421 */ 422 switch (pfs->pfs_type) { 423 case Proot: 424 case Pcurproc: 425 procp = 0; 426 break; 427 428 default: 429 procp = PFIND(pfs->pfs_pid); 430 if (procp == NULL || procp->p_ucred == NULL) 431 return (ENOENT); 432 } 433 434 error = 0; 435 436 /* start by zeroing out the attributes */ 437 VATTR_NULL(vap); 438 439 /* next do all the common fields */ 440 vap->va_type = ap->a_vp->v_type; 441 vap->va_mode = pfs->pfs_mode; 442 vap->va_fileid = pfs->pfs_fileno; 443 vap->va_flags = 0; 444 vap->va_blocksize = PAGE_SIZE; 445 vap->va_bytes = vap->va_size = 0; 446 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; 447 448 /* 449 * Make all times be current TOD. 450 * It would be possible to get the process start 451 * time from the p_stat structure, but there's 452 * no "file creation" time stamp anyway, and the 453 * p_stat structure is not addressible if u. gets 454 * swapped out for that process. 455 */ 456 nanotime(&vap->va_ctime); 457 vap->va_atime = vap->va_mtime = vap->va_ctime; 458 459 /* 460 * If the process has exercised some setuid or setgid 461 * privilege, then rip away read/write permission so 462 * that only root can gain access. 463 */ 464 switch (pfs->pfs_type) { 465 case Pctl: 466 case Pregs: 467 case Pfpregs: 468 case Pdbregs: 469 case Pmem: 470 if (procp->p_flag & P_SUGID) 471 vap->va_mode &= ~((VREAD|VWRITE)| 472 ((VREAD|VWRITE)>>3)| 473 ((VREAD|VWRITE)>>6)); 474 break; 475 default: 476 break; 477 } 478 479 /* 480 * now do the object specific fields 481 * 482 * The size could be set from struct reg, but it's hardly 483 * worth the trouble, and it puts some (potentially) machine 484 * dependent data into this machine-independent code. If it 485 * becomes important then this function should break out into 486 * a per-file stat function in the corresponding .c file. 487 */ 488 489 vap->va_nlink = 1; 490 if (procp) { 491 vap->va_uid = procp->p_ucred->cr_uid; 492 vap->va_gid = procp->p_ucred->cr_gid; 493 } 494 495 switch (pfs->pfs_type) { 496 case Proot: 497 /* 498 * Set nlink to 1 to tell fts(3) we don't actually know. 499 */ 500 vap->va_nlink = 1; 501 vap->va_uid = 0; 502 vap->va_gid = 0; 503 vap->va_size = vap->va_bytes = DEV_BSIZE; 504 break; 505 506 case Pcurproc: { 507 char buf[16]; /* should be enough */ 508 vap->va_uid = 0; 509 vap->va_gid = 0; 510 vap->va_size = vap->va_bytes = 511 snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); 512 break; 513 } 514 515 case Pproc: 516 vap->va_nlink = nproc_targets; 517 vap->va_size = vap->va_bytes = DEV_BSIZE; 518 break; 519 520 case Pfile: { 521 char *fullpath, *freepath; 522 error = vn_fullpath(procp, NULL, &fullpath, &freepath); 523 if (error == 0) { 524 vap->va_size = strlen(fullpath); 525 free(freepath, M_TEMP); 526 } else { 527 vap->va_size = sizeof("unknown") - 1; 528 error = 0; 529 } 530 vap->va_bytes = vap->va_size; 531 break; 532 } 533 534 case Pmem: 535 /* 536 * If we denied owner access earlier, then we have to 537 * change the owner to root - otherwise 'ps' and friends 538 * will break even though they are setgid kmem. *SIGH* 539 */ 540 if (procp->p_flag & P_SUGID) 541 vap->va_uid = 0; 542 else 543 vap->va_uid = procp->p_ucred->cr_uid; 544 break; 545 546 case Pregs: 547 vap->va_bytes = vap->va_size = sizeof(struct reg); 548 break; 549 550 case Pfpregs: 551 vap->va_bytes = vap->va_size = sizeof(struct fpreg); 552 break; 553 554 case Pdbregs: 555 vap->va_bytes = vap->va_size = sizeof(struct dbreg); 556 break; 557 558 case Ptype: 559 case Pmap: 560 case Pctl: 561 case Pstatus: 562 case Pnote: 563 case Pnotepg: 564 case Pcmdline: 565 case Prlimit: 566 break; 567 568 default: 569 panic("procfs_getattr"); 570 } 571 572 return (error); 573 } 574 575 /* 576 * procfs_setattr(struct vnode *a_vp, struct vattr *a_vap, 577 * struct ucred *a_cred, struct thread *a_td) 578 */ 579 static int 580 procfs_setattr(struct vop_setattr_args *ap) 581 { 582 if (ap->a_vap->va_flags != VNOVAL) 583 return (EOPNOTSUPP); 584 585 /* 586 * just fake out attribute setting 587 * it's not good to generate an error 588 * return, otherwise things like creat() 589 * will fail when they try to set the 590 * file length to 0. worse, this means 591 * that echo $note > /proc/$pid/note will fail. 592 */ 593 594 return (0); 595 } 596 597 /* 598 * implement access checking. 599 * 600 * something very similar to this code is duplicated 601 * throughout the 4bsd kernel and should be moved 602 * into kern/vfs_subr.c sometime. 603 * 604 * actually, the check for super-user is slightly 605 * broken since it will allow read access to write-only 606 * objects. this doesn't cause any particular trouble 607 * but does mean that the i/o entry points need to check 608 * that the operation really does make sense. 609 * 610 * procfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred, 611 * struct thread *a_td) 612 */ 613 static int 614 procfs_access(struct vop_access_args *ap) 615 { 616 struct vattr *vap; 617 struct vattr vattr; 618 int error; 619 620 /* 621 * If you're the super-user, 622 * you always get access. 623 */ 624 if (ap->a_cred->cr_uid == 0) 625 return (0); 626 627 vap = &vattr; 628 error = VOP_GETATTR(ap->a_vp, vap, ap->a_td); 629 if (error) 630 return (error); 631 632 /* 633 * Access check is based on only one of owner, group, public. 634 * If not owner, then check group. If not a member of the 635 * group, then check public access. 636 */ 637 if (ap->a_cred->cr_uid != vap->va_uid) { 638 gid_t *gp; 639 int i; 640 641 ap->a_mode >>= 3; 642 gp = ap->a_cred->cr_groups; 643 for (i = 0; i < ap->a_cred->cr_ngroups; i++, gp++) 644 if (vap->va_gid == *gp) 645 goto found; 646 ap->a_mode >>= 3; 647 found: 648 ; 649 } 650 651 if ((vap->va_mode & ap->a_mode) == ap->a_mode) 652 return (0); 653 654 return (EACCES); 655 } 656 657 /* 658 * lookup. this is incredibly complicated in the 659 * general case, however for most pseudo-filesystems 660 * very little needs to be done. 661 * 662 * unless you want to get a migraine, just make sure your 663 * filesystem doesn't do any locking of its own. otherwise 664 * read and inwardly digest ufs_lookup(). 665 * 666 * procfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp, 667 * struct componentname *a_cnp) 668 */ 669 static int 670 procfs_lookup(struct vop_lookup_args *ap) 671 { 672 struct componentname *cnp = ap->a_cnp; 673 struct vnode **vpp = ap->a_vpp; 674 struct vnode *dvp = ap->a_dvp; 675 char *pname = cnp->cn_nameptr; 676 /* struct proc *curp = cnp->cn_proc; */ 677 struct proc_target *pt; 678 pid_t pid; 679 struct pfsnode *pfs; 680 struct proc *p; 681 int i; 682 683 *vpp = NULL; 684 685 if (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME) 686 return (EROFS); 687 688 if (cnp->cn_namelen == 1 && *pname == '.') { 689 *vpp = dvp; 690 vref(dvp); 691 /* vn_lock(dvp, NULL, LK_EXCLUSIVE | LK_RETRY, curp); */ 692 return (0); 693 } 694 695 pfs = VTOPFS(dvp); 696 switch (pfs->pfs_type) { 697 case Proot: 698 if (cnp->cn_flags & CNP_ISDOTDOT) 699 return (EIO); 700 701 if (CNEQ(cnp, "curproc", 7)) 702 return (procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc)); 703 704 pid = atopid(pname, cnp->cn_namelen); 705 if (pid == NO_PID) 706 break; 707 708 p = PFIND(pid); 709 if (p == NULL) 710 break; 711 712 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 && 713 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid) 714 break; 715 716 return (procfs_allocvp(dvp->v_mount, vpp, pid, Pproc)); 717 718 case Pproc: 719 if (cnp->cn_flags & CNP_ISDOTDOT) 720 return (procfs_root(dvp->v_mount, vpp)); 721 722 p = PFIND(pfs->pfs_pid); 723 if (p == NULL) 724 break; 725 726 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 && 727 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid) 728 break; 729 730 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) { 731 if (cnp->cn_namelen == pt->pt_namlen && 732 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 && 733 (pt->pt_valid == NULL || (*pt->pt_valid)(p))) 734 goto found; 735 } 736 break; 737 found: 738 return (procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid, 739 pt->pt_pfstype)); 740 741 default: 742 return (ENOTDIR); 743 } 744 745 return (cnp->cn_nameiop == NAMEI_LOOKUP ? ENOENT : EROFS); 746 } 747 748 /* 749 * Does this process have a text file? 750 */ 751 int 752 procfs_validfile(struct proc *p) 753 { 754 return (procfs_findtextvp(p) != NULLVP); 755 } 756 757 /* 758 * readdir() returns directory entries from pfsnode (vp). 759 * 760 * We generate just one directory entry at a time, as it would probably 761 * not pay off to buffer several entries locally to save uiomove calls. 762 * 763 * procfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred, 764 * int *a_eofflag, int *a_ncookies, u_long **a_cookies) 765 */ 766 static int 767 procfs_readdir(struct vop_readdir_args *ap) 768 { 769 struct uio *uio = ap->a_uio; 770 struct dirent d; 771 struct dirent *dp = &d; 772 struct pfsnode *pfs; 773 int count, error, i, off; 774 static u_int delen; 775 776 if (!delen) { 777 778 d.d_namlen = PROCFS_NAMELEN; 779 delen = GENERIC_DIRSIZ(&d); 780 } 781 782 pfs = VTOPFS(ap->a_vp); 783 784 off = (int)uio->uio_offset; 785 if (off != uio->uio_offset || off < 0 || 786 off % delen != 0 || uio->uio_resid < delen) 787 return (EINVAL); 788 789 error = 0; 790 count = 0; 791 i = off / delen; 792 793 switch (pfs->pfs_type) { 794 /* 795 * this is for the process-specific sub-directories. 796 * all that is needed to is copy out all the entries 797 * from the procent[] table (top of this file). 798 */ 799 case Pproc: { 800 struct proc *p; 801 struct proc_target *pt; 802 803 p = PFIND(pfs->pfs_pid); 804 if (p == NULL) 805 break; 806 if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) 807 break; 808 809 for (pt = &proc_targets[i]; 810 uio->uio_resid >= delen && i < nproc_targets; pt++, i++) { 811 if (pt->pt_valid && (*pt->pt_valid)(p) == 0) 812 continue; 813 814 dp->d_reclen = delen; 815 dp->d_fileno = PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype); 816 dp->d_namlen = pt->pt_namlen; 817 bcopy(pt->pt_name, dp->d_name, pt->pt_namlen + 1); 818 dp->d_type = pt->pt_type; 819 820 if ((error = uiomove((caddr_t)dp, delen, uio)) != 0) 821 break; 822 } 823 824 break; 825 } 826 827 /* 828 * this is for the root of the procfs filesystem 829 * what is needed is a special entry for "curproc" 830 * followed by an entry for each process on allproc 831 #ifdef PROCFS_ZOMBIE 832 * and zombproc. 833 #endif 834 */ 835 836 case Proot: { 837 #ifdef PROCFS_ZOMBIE 838 int doingzomb = 0; 839 #endif 840 int pcnt = 0; 841 volatile struct proc *p = allproc.lh_first; 842 843 for (; p && uio->uio_resid >= delen; i++, pcnt++) { 844 bzero((char *) dp, delen); 845 dp->d_reclen = delen; 846 847 switch (i) { 848 case 0: /* `.' */ 849 case 1: /* `..' */ 850 dp->d_fileno = PROCFS_FILENO(0, Proot); 851 dp->d_namlen = i + 1; 852 bcopy("..", dp->d_name, dp->d_namlen); 853 dp->d_name[i + 1] = '\0'; 854 dp->d_type = DT_DIR; 855 break; 856 857 case 2: 858 dp->d_fileno = PROCFS_FILENO(0, Pcurproc); 859 dp->d_namlen = 7; 860 bcopy("curproc", dp->d_name, 8); 861 dp->d_type = DT_LNK; 862 break; 863 864 default: 865 while (pcnt < i) { 866 p = p->p_list.le_next; 867 if (!p) 868 goto done; 869 if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) 870 continue; 871 pcnt++; 872 } 873 while (!PRISON_CHECK(ap->a_cred, p->p_ucred)) { 874 p = p->p_list.le_next; 875 if (!p) 876 goto done; 877 } 878 if (ps_showallprocs == 0 && 879 ap->a_cred->cr_uid != 0 && 880 ap->a_cred->cr_uid != 881 p->p_ucred->cr_uid) { 882 p = p->p_list.le_next; 883 if (!p) 884 goto done; 885 break; 886 } 887 888 dp->d_fileno = PROCFS_FILENO(p->p_pid, Pproc); 889 dp->d_namlen = sprintf(dp->d_name, "%ld", 890 (long)p->p_pid); 891 dp->d_type = DT_DIR; 892 p = p->p_list.le_next; 893 break; 894 } 895 896 if ((error = uiomove((caddr_t)dp, delen, uio)) != 0) 897 break; 898 } 899 done: 900 901 #ifdef PROCFS_ZOMBIE 902 if (p == NULL && doingzomb == 0) { 903 doingzomb = 1; 904 p = zombproc.lh_first; 905 goto again; 906 } 907 #endif 908 909 break; 910 911 } 912 913 default: 914 error = ENOTDIR; 915 break; 916 } 917 918 uio->uio_offset = i * delen; 919 920 return (error); 921 } 922 923 /* 924 * readlink reads the link of `curproc' or `file' 925 */ 926 static int 927 procfs_readlink(struct vop_readlink_args *ap) 928 { 929 char buf[16]; /* should be enough */ 930 struct proc *procp; 931 struct vnode *vp = ap->a_vp; 932 struct pfsnode *pfs = VTOPFS(vp); 933 char *fullpath, *freepath; 934 int error, len; 935 936 switch (pfs->pfs_type) { 937 case Pcurproc: 938 if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc)) 939 return (EINVAL); 940 941 len = snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); 942 943 return (uiomove(buf, len, ap->a_uio)); 944 /* 945 * There _should_ be no way for an entire process to disappear 946 * from under us... 947 */ 948 case Pfile: 949 procp = PFIND(pfs->pfs_pid); 950 if (procp == NULL || procp->p_ucred == NULL) { 951 printf("procfs_readlink: pid %d disappeared\n", 952 pfs->pfs_pid); 953 return (uiomove("unknown", sizeof("unknown") - 1, 954 ap->a_uio)); 955 } 956 error = vn_fullpath(procp, NULL, &fullpath, &freepath); 957 if (error != 0) 958 return (uiomove("unknown", sizeof("unknown") - 1, 959 ap->a_uio)); 960 error = uiomove(fullpath, strlen(fullpath), ap->a_uio); 961 free(freepath, M_TEMP); 962 return (error); 963 default: 964 return (EINVAL); 965 } 966 } 967 968 /* 969 * convert decimal ascii to pid_t 970 */ 971 static pid_t 972 atopid(const char *b, u_int len) 973 { 974 pid_t p = 0; 975 976 while (len--) { 977 char c = *b++; 978 if (c < '0' || c > '9') 979 return (NO_PID); 980 p = 10 * p + (c - '0'); 981 if (p > PID_MAX) 982 return (NO_PID); 983 } 984 985 return (p); 986 } 987 988 /* 989 * procfs vnode operations. 990 */ 991 struct vnodeopv_entry_desc procfs_vnodeop_entries[] = { 992 { &vop_default_desc, vop_defaultop }, 993 { &vop_access_desc, (void *) procfs_access }, 994 { &vop_advlock_desc, (void *) procfs_badop }, 995 { &vop_bmap_desc, (void *) procfs_bmap }, 996 { &vop_close_desc, (void *) procfs_close }, 997 { &vop_create_desc, (void *) procfs_badop }, 998 { &vop_getattr_desc, (void *) procfs_getattr }, 999 { &vop_inactive_desc, (void *) procfs_inactive }, 1000 { &vop_link_desc, (void *) procfs_badop }, 1001 { &vop_lookup_desc, (void *) procfs_lookup }, 1002 { &vop_mkdir_desc, (void *) procfs_badop }, 1003 { &vop_mknod_desc, (void *) procfs_badop }, 1004 { &vop_open_desc, (void *) procfs_open }, 1005 { &vop_pathconf_desc, (void *) vop_stdpathconf }, 1006 { &vop_print_desc, (void *) procfs_print }, 1007 { &vop_read_desc, (void *) procfs_rw }, 1008 { &vop_readdir_desc, (void *) procfs_readdir }, 1009 { &vop_readlink_desc, (void *) procfs_readlink }, 1010 { &vop_reclaim_desc, (void *) procfs_reclaim }, 1011 { &vop_remove_desc, (void *) procfs_badop }, 1012 { &vop_rename_desc, (void *) procfs_badop }, 1013 { &vop_rmdir_desc, (void *) procfs_badop }, 1014 { &vop_setattr_desc, (void *) procfs_setattr }, 1015 { &vop_symlink_desc, (void *) procfs_badop }, 1016 { &vop_write_desc, (void *) procfs_rw }, 1017 { &vop_ioctl_desc, (void *) procfs_ioctl }, 1018 { NULL, NULL } 1019 }; 1020 1021