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 1.6 2003/07/19 21:14:42 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 <miscfs/procfs/procfs.h> 64 #include <sys/pioctl.h> 65 66 static int procfs_access __P((struct vop_access_args *)); 67 static int procfs_badop __P((void)); 68 static int procfs_bmap __P((struct vop_bmap_args *)); 69 static int procfs_close __P((struct vop_close_args *)); 70 static int procfs_getattr __P((struct vop_getattr_args *)); 71 static int procfs_inactive __P((struct vop_inactive_args *)); 72 static int procfs_ioctl __P((struct vop_ioctl_args *)); 73 static int procfs_lookup __P((struct vop_lookup_args *)); 74 static int procfs_open __P((struct vop_open_args *)); 75 static int procfs_print __P((struct vop_print_args *)); 76 static int procfs_readdir __P((struct vop_readdir_args *)); 77 static int procfs_readlink __P((struct vop_readlink_args *)); 78 static int procfs_reclaim __P((struct vop_reclaim_args *)); 79 static int procfs_setattr __P((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) __P((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 __P((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 static int 128 procfs_open(ap) 129 struct vop_open_args /* { 130 struct vnode *a_vp; 131 int a_mode; 132 struct ucred *a_cred; 133 struct thread *a_td; 134 } */ *ap; 135 { 136 struct pfsnode *pfs = VTOPFS(ap->a_vp); 137 struct proc *p1, *p2; 138 139 p2 = PFIND(pfs->pfs_pid); 140 if (p2 == NULL) 141 return (ENOENT); 142 if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred)) 143 return (ENOENT); 144 145 switch (pfs->pfs_type) { 146 case Pmem: 147 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) || 148 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) 149 return (EBUSY); 150 151 p1 = ap->a_td->td_proc; 152 KKASSERT(p1); 153 /* Can't trace a process that's currently exec'ing. */ 154 if ((p2->p_flag & P_INEXEC) != 0) 155 return EAGAIN; 156 if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred)) 157 return (EPERM); 158 159 if (ap->a_mode & FWRITE) 160 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL); 161 162 return (0); 163 164 default: 165 break; 166 } 167 168 return (0); 169 } 170 171 /* 172 * close the pfsnode (vp) after doing i/o. 173 * (vp) is not locked on entry or exit. 174 * 175 * nothing to do for procfs other than undo 176 * any exclusive open flag (see _open above). 177 */ 178 static int 179 procfs_close(ap) 180 struct vop_close_args /* { 181 struct vnode *a_vp; 182 int a_fflag; 183 struct ucred *a_cred; 184 struct thread *a_td; 185 } */ *ap; 186 { 187 struct pfsnode *pfs = VTOPFS(ap->a_vp); 188 struct proc *p; 189 190 switch (pfs->pfs_type) { 191 case Pmem: 192 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL)) 193 pfs->pfs_flags &= ~(FWRITE|O_EXCL); 194 /* 195 * This rather complicated-looking code is trying to 196 * determine if this was the last close on this particular 197 * vnode. While one would expect v_usecount to be 1 at 198 * that point, it seems that (according to John Dyson) 199 * the VM system will bump up the usecount. So: if the 200 * usecount is 2, and VOBJBUF is set, then this is really 201 * the last close. Otherwise, if the usecount is < 2 202 * then it is definitely the last close. 203 * If this is the last close, then it checks to see if 204 * the target process has PF_LINGER set in p_pfsflags, 205 * if this is *not* the case, then the process' stop flags 206 * are cleared, and the process is woken up. This is 207 * to help prevent the case where a process has been 208 * told to stop on an event, but then the requesting process 209 * has gone away or forgotten about it. 210 */ 211 if ((ap->a_vp->v_usecount < 2) 212 && (p = pfind(pfs->pfs_pid)) 213 && !(p->p_pfsflags & PF_LINGER)) { 214 p->p_stops = 0; 215 p->p_step = 0; 216 wakeup(&p->p_step); 217 } 218 break; 219 default: 220 break; 221 } 222 223 return (0); 224 } 225 226 /* 227 * do an ioctl operation on a pfsnode (vp). 228 * (vp) is not locked on entry or exit. 229 */ 230 static int 231 procfs_ioctl(ap) 232 struct vop_ioctl_args *ap; 233 { 234 struct pfsnode *pfs = VTOPFS(ap->a_vp); 235 struct proc *procp; 236 struct proc *p; 237 int error; 238 int signo; 239 struct procfs_status *psp; 240 unsigned char flags; 241 242 procp = pfind(pfs->pfs_pid); 243 if (procp == NULL) 244 return ENOTTY; 245 p = ap->a_td->td_proc; 246 if (p == NULL) 247 return EINVAL; 248 249 /* Can't trace a process that's currently exec'ing. */ 250 if ((procp->p_flag & P_INEXEC) != 0) 251 return EAGAIN; 252 if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred)) 253 return EPERM; 254 255 switch (ap->a_command) { 256 case PIOCBIS: 257 procp->p_stops |= *(unsigned int*)ap->a_data; 258 break; 259 case PIOCBIC: 260 procp->p_stops &= ~*(unsigned int*)ap->a_data; 261 break; 262 case PIOCSFL: 263 /* 264 * NFLAGS is "non-suser_xxx flags" -- currently, only 265 * PFS_ISUGID ("ignore set u/g id"); 266 */ 267 #define NFLAGS (PF_ISUGID) 268 flags = (unsigned char)*(unsigned int*)ap->a_data; 269 if (flags & NFLAGS && (error = suser_cred(ap->a_cred, 0))) 270 return error; 271 procp->p_pfsflags = flags; 272 break; 273 case PIOCGFL: 274 *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags; 275 break; 276 case PIOCSTATUS: 277 psp = (struct procfs_status *)ap->a_data; 278 psp->state = (procp->p_step == 0); 279 psp->flags = procp->p_pfsflags; 280 psp->events = procp->p_stops; 281 if (procp->p_step) { 282 psp->why = procp->p_stype; 283 psp->val = procp->p_xstat; 284 } else { 285 psp->why = psp->val = 0; /* Not defined values */ 286 } 287 break; 288 case PIOCWAIT: 289 psp = (struct procfs_status *)ap->a_data; 290 if (procp->p_step == 0) { 291 error = tsleep(&procp->p_stype, PCATCH, "piocwait", 0); 292 if (error) 293 return error; 294 } 295 psp->state = 1; /* It stopped */ 296 psp->flags = procp->p_pfsflags; 297 psp->events = procp->p_stops; 298 psp->why = procp->p_stype; /* why it stopped */ 299 psp->val = procp->p_xstat; /* any extra info */ 300 break; 301 case PIOCCONT: /* Restart a proc */ 302 if (procp->p_step == 0) 303 return EINVAL; /* Can only start a stopped process */ 304 if ((signo = *(int*)ap->a_data) != 0) { 305 if (signo >= NSIG || signo <= 0) 306 return EINVAL; 307 psignal(procp, signo); 308 } 309 procp->p_step = 0; 310 wakeup(&procp->p_step); 311 break; 312 default: 313 return (ENOTTY); 314 } 315 return 0; 316 } 317 318 /* 319 * do block mapping for pfsnode (vp). 320 * since we don't use the buffer cache 321 * for procfs this function should never 322 * be called. in any case, it's not clear 323 * what part of the kernel ever makes use 324 * of this function. for sanity, this is the 325 * usual no-op bmap, although returning 326 * (EIO) would be a reasonable alternative. 327 */ 328 static int 329 procfs_bmap(ap) 330 struct vop_bmap_args /* { 331 struct vnode *a_vp; 332 daddr_t a_bn; 333 struct vnode **a_vpp; 334 daddr_t *a_bnp; 335 int *a_runp; 336 } */ *ap; 337 { 338 339 if (ap->a_vpp != NULL) 340 *ap->a_vpp = ap->a_vp; 341 if (ap->a_bnp != NULL) 342 *ap->a_bnp = ap->a_bn; 343 if (ap->a_runp != NULL) 344 *ap->a_runp = 0; 345 return (0); 346 } 347 348 /* 349 * procfs_inactive is called when the pfsnode 350 * is vrele'd and the reference count goes 351 * to zero. (vp) will be on the vnode free 352 * list, so to get it back vget() must be 353 * used. 354 * 355 * (vp) is locked on entry, but must be unlocked on exit. 356 */ 357 static int 358 procfs_inactive(ap) 359 struct vop_inactive_args /* { 360 struct vnode *a_vp; 361 struct thread *a_td; 362 } */ *ap; 363 { 364 struct vnode *vp = ap->a_vp; 365 366 VOP_UNLOCK(vp, 0, ap->a_td); 367 368 return (0); 369 } 370 371 /* 372 * _reclaim is called when getnewvnode() 373 * wants to make use of an entry on the vnode 374 * free list. at this time the filesystem needs 375 * to free any private data and remove the node 376 * from any private lists. 377 */ 378 static int 379 procfs_reclaim(ap) 380 struct vop_reclaim_args /* { 381 struct vnode *a_vp; 382 } */ *ap; 383 { 384 385 return (procfs_freevp(ap->a_vp)); 386 } 387 388 /* 389 * _print is used for debugging. 390 * just print a readable description 391 * of (vp). 392 */ 393 static int 394 procfs_print(ap) 395 struct vop_print_args /* { 396 struct vnode *a_vp; 397 } */ *ap; 398 { 399 struct pfsnode *pfs = VTOPFS(ap->a_vp); 400 401 printf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n", 402 pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags); 403 return (0); 404 } 405 406 /* 407 * generic entry point for unsupported operations 408 */ 409 static int 410 procfs_badop() 411 { 412 413 return (EIO); 414 } 415 416 /* 417 * Invent attributes for pfsnode (vp) and store 418 * them in (vap). 419 * Directories lengths are returned as zero since 420 * any real length would require the genuine size 421 * to be computed, and nothing cares anyway. 422 * 423 * this is relatively minimal for procfs. 424 */ 425 static int 426 procfs_getattr(ap) 427 struct vop_getattr_args /* { 428 struct vnode *a_vp; 429 struct vattr *a_vap; 430 struct ucred *a_cred; 431 struct thread *a_td; 432 } */ *ap; 433 { 434 struct pfsnode *pfs = VTOPFS(ap->a_vp); 435 struct vattr *vap = ap->a_vap; 436 struct proc *procp; 437 int error; 438 439 /* 440 * First make sure that the process and its credentials 441 * still exist. 442 */ 443 switch (pfs->pfs_type) { 444 case Proot: 445 case Pcurproc: 446 procp = 0; 447 break; 448 449 default: 450 procp = PFIND(pfs->pfs_pid); 451 if (procp == NULL || procp->p_ucred == NULL) 452 return (ENOENT); 453 } 454 455 error = 0; 456 457 /* start by zeroing out the attributes */ 458 VATTR_NULL(vap); 459 460 /* next do all the common fields */ 461 vap->va_type = ap->a_vp->v_type; 462 vap->va_mode = pfs->pfs_mode; 463 vap->va_fileid = pfs->pfs_fileno; 464 vap->va_flags = 0; 465 vap->va_blocksize = PAGE_SIZE; 466 vap->va_bytes = vap->va_size = 0; 467 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; 468 469 /* 470 * Make all times be current TOD. 471 * It would be possible to get the process start 472 * time from the p_stat structure, but there's 473 * no "file creation" time stamp anyway, and the 474 * p_stat structure is not addressible if u. gets 475 * swapped out for that process. 476 */ 477 nanotime(&vap->va_ctime); 478 vap->va_atime = vap->va_mtime = vap->va_ctime; 479 480 /* 481 * If the process has exercised some setuid or setgid 482 * privilege, then rip away read/write permission so 483 * that only root can gain access. 484 */ 485 switch (pfs->pfs_type) { 486 case Pctl: 487 case Pregs: 488 case Pfpregs: 489 case Pdbregs: 490 case Pmem: 491 if (procp->p_flag & P_SUGID) 492 vap->va_mode &= ~((VREAD|VWRITE)| 493 ((VREAD|VWRITE)>>3)| 494 ((VREAD|VWRITE)>>6)); 495 break; 496 default: 497 break; 498 } 499 500 /* 501 * now do the object specific fields 502 * 503 * The size could be set from struct reg, but it's hardly 504 * worth the trouble, and it puts some (potentially) machine 505 * dependent data into this machine-independent code. If it 506 * becomes important then this function should break out into 507 * a per-file stat function in the corresponding .c file. 508 */ 509 510 vap->va_nlink = 1; 511 if (procp) { 512 vap->va_uid = procp->p_ucred->cr_uid; 513 vap->va_gid = procp->p_ucred->cr_gid; 514 } 515 516 switch (pfs->pfs_type) { 517 case Proot: 518 /* 519 * Set nlink to 1 to tell fts(3) we don't actually know. 520 */ 521 vap->va_nlink = 1; 522 vap->va_uid = 0; 523 vap->va_gid = 0; 524 vap->va_size = vap->va_bytes = DEV_BSIZE; 525 break; 526 527 case Pcurproc: { 528 char buf[16]; /* should be enough */ 529 vap->va_uid = 0; 530 vap->va_gid = 0; 531 vap->va_size = vap->va_bytes = 532 snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); 533 break; 534 } 535 536 case Pproc: 537 vap->va_nlink = nproc_targets; 538 vap->va_size = vap->va_bytes = DEV_BSIZE; 539 break; 540 541 case Pfile: { 542 char *fullpath, *freepath; 543 error = textvp_fullpath(procp, &fullpath, &freepath); 544 if (error == 0) { 545 vap->va_size = strlen(fullpath); 546 free(freepath, M_TEMP); 547 } else { 548 vap->va_size = sizeof("unknown") - 1; 549 error = 0; 550 } 551 vap->va_bytes = vap->va_size; 552 break; 553 } 554 555 case Pmem: 556 /* 557 * If we denied owner access earlier, then we have to 558 * change the owner to root - otherwise 'ps' and friends 559 * will break even though they are setgid kmem. *SIGH* 560 */ 561 if (procp->p_flag & P_SUGID) 562 vap->va_uid = 0; 563 else 564 vap->va_uid = procp->p_ucred->cr_uid; 565 break; 566 567 case Pregs: 568 vap->va_bytes = vap->va_size = sizeof(struct reg); 569 break; 570 571 case Pfpregs: 572 vap->va_bytes = vap->va_size = sizeof(struct fpreg); 573 break; 574 575 case Pdbregs: 576 vap->va_bytes = vap->va_size = sizeof(struct dbreg); 577 break; 578 579 case Ptype: 580 case Pmap: 581 case Pctl: 582 case Pstatus: 583 case Pnote: 584 case Pnotepg: 585 case Pcmdline: 586 case Prlimit: 587 break; 588 589 default: 590 panic("procfs_getattr"); 591 } 592 593 return (error); 594 } 595 596 static int 597 procfs_setattr(ap) 598 struct vop_setattr_args /* { 599 struct vnode *a_vp; 600 struct vattr *a_vap; 601 struct ucred *a_cred; 602 struct thread *a_td; 603 } */ *ap; 604 { 605 606 if (ap->a_vap->va_flags != VNOVAL) 607 return (EOPNOTSUPP); 608 609 /* 610 * just fake out attribute setting 611 * it's not good to generate an error 612 * return, otherwise things like creat() 613 * will fail when they try to set the 614 * file length to 0. worse, this means 615 * that echo $note > /proc/$pid/note will fail. 616 */ 617 618 return (0); 619 } 620 621 /* 622 * implement access checking. 623 * 624 * something very similar to this code is duplicated 625 * throughout the 4bsd kernel and should be moved 626 * into kern/vfs_subr.c sometime. 627 * 628 * actually, the check for super-user is slightly 629 * broken since it will allow read access to write-only 630 * objects. this doesn't cause any particular trouble 631 * but does mean that the i/o entry points need to check 632 * that the operation really does make sense. 633 */ 634 static int 635 procfs_access(ap) 636 struct vop_access_args /* { 637 struct vnode *a_vp; 638 int a_mode; 639 struct ucred *a_cred; 640 struct thread *a_td; 641 } */ *ap; 642 { 643 struct vattr *vap; 644 struct vattr vattr; 645 int error; 646 647 /* 648 * If you're the super-user, 649 * you always get access. 650 */ 651 if (ap->a_cred->cr_uid == 0) 652 return (0); 653 654 vap = &vattr; 655 error = VOP_GETATTR(ap->a_vp, vap, ap->a_td); 656 if (error) 657 return (error); 658 659 /* 660 * Access check is based on only one of owner, group, public. 661 * If not owner, then check group. If not a member of the 662 * group, then check public access. 663 */ 664 if (ap->a_cred->cr_uid != vap->va_uid) { 665 gid_t *gp; 666 int i; 667 668 ap->a_mode >>= 3; 669 gp = ap->a_cred->cr_groups; 670 for (i = 0; i < ap->a_cred->cr_ngroups; i++, gp++) 671 if (vap->va_gid == *gp) 672 goto found; 673 ap->a_mode >>= 3; 674 found: 675 ; 676 } 677 678 if ((vap->va_mode & ap->a_mode) == ap->a_mode) 679 return (0); 680 681 return (EACCES); 682 } 683 684 /* 685 * lookup. this is incredibly complicated in the 686 * general case, however for most pseudo-filesystems 687 * very little needs to be done. 688 * 689 * unless you want to get a migraine, just make sure your 690 * filesystem doesn't do any locking of its own. otherwise 691 * read and inwardly digest ufs_lookup(). 692 */ 693 static int 694 procfs_lookup(ap) 695 struct vop_lookup_args /* { 696 struct vnode * a_dvp; 697 struct vnode ** a_vpp; 698 struct componentname * a_cnp; 699 } */ *ap; 700 { 701 struct componentname *cnp = ap->a_cnp; 702 struct vnode **vpp = ap->a_vpp; 703 struct vnode *dvp = ap->a_dvp; 704 char *pname = cnp->cn_nameptr; 705 /* struct proc *curp = cnp->cn_proc; */ 706 struct proc_target *pt; 707 pid_t pid; 708 struct pfsnode *pfs; 709 struct proc *p; 710 int i; 711 712 *vpp = NULL; 713 714 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 715 return (EROFS); 716 717 if (cnp->cn_namelen == 1 && *pname == '.') { 718 *vpp = dvp; 719 VREF(dvp); 720 /* vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, curp); */ 721 return (0); 722 } 723 724 pfs = VTOPFS(dvp); 725 switch (pfs->pfs_type) { 726 case Proot: 727 if (cnp->cn_flags & ISDOTDOT) 728 return (EIO); 729 730 if (CNEQ(cnp, "curproc", 7)) 731 return (procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc)); 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; 740 741 return (procfs_allocvp(dvp->v_mount, vpp, pid, Pproc)); 742 743 case Pproc: 744 if (cnp->cn_flags & ISDOTDOT) 745 return (procfs_root(dvp->v_mount, vpp)); 746 747 p = PFIND(pfs->pfs_pid); 748 if (p == NULL) 749 break; 750 751 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) { 752 if (cnp->cn_namelen == pt->pt_namlen && 753 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 && 754 (pt->pt_valid == NULL || (*pt->pt_valid)(p))) 755 goto found; 756 } 757 break; 758 found: 759 return (procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid, 760 pt->pt_pfstype)); 761 762 default: 763 return (ENOTDIR); 764 } 765 766 return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS); 767 } 768 769 /* 770 * Does this process have a text file? 771 */ 772 int 773 procfs_validfile(p) 774 struct proc *p; 775 { 776 777 return (procfs_findtextvp(p) != NULLVP); 778 } 779 780 /* 781 * readdir() returns directory entries from pfsnode (vp). 782 * 783 * We generate just one directory entry at a time, as it would probably 784 * not pay off to buffer several entries locally to save uiomove calls. 785 */ 786 static int 787 procfs_readdir(ap) 788 struct vop_readdir_args /* { 789 struct vnode *a_vp; 790 struct uio *a_uio; 791 struct ucred *a_cred; 792 int *a_eofflag; 793 int *a_ncookies; 794 u_long **a_cookies; 795 } */ *ap; 796 { 797 struct uio *uio = ap->a_uio; 798 struct dirent d; 799 struct dirent *dp = &d; 800 struct pfsnode *pfs; 801 int count, error, i, off; 802 static u_int delen; 803 804 if (!delen) { 805 806 d.d_namlen = PROCFS_NAMELEN; 807 delen = GENERIC_DIRSIZ(&d); 808 } 809 810 pfs = VTOPFS(ap->a_vp); 811 812 off = (int)uio->uio_offset; 813 if (off != uio->uio_offset || off < 0 || 814 off % delen != 0 || uio->uio_resid < delen) 815 return (EINVAL); 816 817 error = 0; 818 count = 0; 819 i = off / delen; 820 821 switch (pfs->pfs_type) { 822 /* 823 * this is for the process-specific sub-directories. 824 * all that is needed to is copy out all the entries 825 * from the procent[] table (top of this file). 826 */ 827 case Pproc: { 828 struct proc *p; 829 struct proc_target *pt; 830 831 p = PFIND(pfs->pfs_pid); 832 if (p == NULL) 833 break; 834 if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) 835 break; 836 837 for (pt = &proc_targets[i]; 838 uio->uio_resid >= delen && i < nproc_targets; pt++, i++) { 839 if (pt->pt_valid && (*pt->pt_valid)(p) == 0) 840 continue; 841 842 dp->d_reclen = delen; 843 dp->d_fileno = PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype); 844 dp->d_namlen = pt->pt_namlen; 845 bcopy(pt->pt_name, dp->d_name, pt->pt_namlen + 1); 846 dp->d_type = pt->pt_type; 847 848 if ((error = uiomove((caddr_t)dp, delen, uio)) != 0) 849 break; 850 } 851 852 break; 853 } 854 855 /* 856 * this is for the root of the procfs filesystem 857 * what is needed is a special entry for "curproc" 858 * followed by an entry for each process on allproc 859 #ifdef PROCFS_ZOMBIE 860 * and zombproc. 861 #endif 862 */ 863 864 case Proot: { 865 #ifdef PROCFS_ZOMBIE 866 int doingzomb = 0; 867 #endif 868 int pcnt = 0; 869 volatile struct proc *p = allproc.lh_first; 870 871 for (; p && uio->uio_resid >= delen; i++, pcnt++) { 872 bzero((char *) dp, delen); 873 dp->d_reclen = delen; 874 875 switch (i) { 876 case 0: /* `.' */ 877 case 1: /* `..' */ 878 dp->d_fileno = PROCFS_FILENO(0, Proot); 879 dp->d_namlen = i + 1; 880 bcopy("..", dp->d_name, dp->d_namlen); 881 dp->d_name[i + 1] = '\0'; 882 dp->d_type = DT_DIR; 883 break; 884 885 case 2: 886 dp->d_fileno = PROCFS_FILENO(0, Pcurproc); 887 dp->d_namlen = 7; 888 bcopy("curproc", dp->d_name, 8); 889 dp->d_type = DT_LNK; 890 break; 891 892 default: 893 while (pcnt < i) { 894 p = p->p_list.le_next; 895 if (!p) 896 goto done; 897 if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) 898 continue; 899 pcnt++; 900 } 901 while (!PRISON_CHECK(ap->a_cred, p->p_ucred)) { 902 p = p->p_list.le_next; 903 if (!p) 904 goto done; 905 } 906 dp->d_fileno = PROCFS_FILENO(p->p_pid, Pproc); 907 dp->d_namlen = sprintf(dp->d_name, "%ld", 908 (long)p->p_pid); 909 dp->d_type = DT_DIR; 910 p = p->p_list.le_next; 911 break; 912 } 913 914 if ((error = uiomove((caddr_t)dp, delen, uio)) != 0) 915 break; 916 } 917 done: 918 919 #ifdef PROCFS_ZOMBIE 920 if (p == NULL && doingzomb == 0) { 921 doingzomb = 1; 922 p = zombproc.lh_first; 923 goto again; 924 } 925 #endif 926 927 break; 928 929 } 930 931 default: 932 error = ENOTDIR; 933 break; 934 } 935 936 uio->uio_offset = i * delen; 937 938 return (error); 939 } 940 941 /* 942 * readlink reads the link of `curproc' or `file' 943 */ 944 static int 945 procfs_readlink(ap) 946 struct vop_readlink_args *ap; 947 { 948 char buf[16]; /* should be enough */ 949 struct proc *procp; 950 struct vnode *vp = ap->a_vp; 951 struct pfsnode *pfs = VTOPFS(vp); 952 char *fullpath, *freepath; 953 int error, len; 954 955 switch (pfs->pfs_type) { 956 case Pcurproc: 957 if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc)) 958 return (EINVAL); 959 960 len = snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); 961 962 return (uiomove(buf, len, ap->a_uio)); 963 /* 964 * There _should_ be no way for an entire process to disappear 965 * from under us... 966 */ 967 case Pfile: 968 procp = PFIND(pfs->pfs_pid); 969 if (procp == NULL || procp->p_ucred == NULL) { 970 printf("procfs_readlink: pid %d disappeared\n", 971 pfs->pfs_pid); 972 return (uiomove("unknown", sizeof("unknown") - 1, 973 ap->a_uio)); 974 } 975 error = textvp_fullpath(procp, &fullpath, &freepath); 976 if (error != 0) 977 return (uiomove("unknown", sizeof("unknown") - 1, 978 ap->a_uio)); 979 error = uiomove(fullpath, strlen(fullpath), ap->a_uio); 980 free(freepath, M_TEMP); 981 return (error); 982 default: 983 return (EINVAL); 984 } 985 } 986 987 /* 988 * convert decimal ascii to pid_t 989 */ 990 static pid_t 991 atopid(b, len) 992 const char *b; 993 u_int len; 994 { 995 pid_t p = 0; 996 997 while (len--) { 998 char c = *b++; 999 if (c < '0' || c > '9') 1000 return (NO_PID); 1001 p = 10 * p + (c - '0'); 1002 if (p > PID_MAX) 1003 return (NO_PID); 1004 } 1005 1006 return (p); 1007 } 1008 1009 /* 1010 * procfs vnode operations. 1011 */ 1012 vop_t **procfs_vnodeop_p; 1013 static struct vnodeopv_entry_desc procfs_vnodeop_entries[] = { 1014 { &vop_default_desc, (vop_t *) vop_defaultop }, 1015 { &vop_access_desc, (vop_t *) procfs_access }, 1016 { &vop_advlock_desc, (vop_t *) procfs_badop }, 1017 { &vop_bmap_desc, (vop_t *) procfs_bmap }, 1018 { &vop_close_desc, (vop_t *) procfs_close }, 1019 { &vop_create_desc, (vop_t *) procfs_badop }, 1020 { &vop_getattr_desc, (vop_t *) procfs_getattr }, 1021 { &vop_inactive_desc, (vop_t *) procfs_inactive }, 1022 { &vop_link_desc, (vop_t *) procfs_badop }, 1023 { &vop_lookup_desc, (vop_t *) procfs_lookup }, 1024 { &vop_mkdir_desc, (vop_t *) procfs_badop }, 1025 { &vop_mknod_desc, (vop_t *) procfs_badop }, 1026 { &vop_open_desc, (vop_t *) procfs_open }, 1027 { &vop_pathconf_desc, (vop_t *) vop_stdpathconf }, 1028 { &vop_print_desc, (vop_t *) procfs_print }, 1029 { &vop_read_desc, (vop_t *) procfs_rw }, 1030 { &vop_readdir_desc, (vop_t *) procfs_readdir }, 1031 { &vop_readlink_desc, (vop_t *) procfs_readlink }, 1032 { &vop_reclaim_desc, (vop_t *) procfs_reclaim }, 1033 { &vop_remove_desc, (vop_t *) procfs_badop }, 1034 { &vop_rename_desc, (vop_t *) procfs_badop }, 1035 { &vop_rmdir_desc, (vop_t *) procfs_badop }, 1036 { &vop_setattr_desc, (vop_t *) procfs_setattr }, 1037 { &vop_symlink_desc, (vop_t *) procfs_badop }, 1038 { &vop_write_desc, (vop_t *) procfs_rw }, 1039 { &vop_ioctl_desc, (vop_t *) procfs_ioctl }, 1040 { NULL, NULL } 1041 }; 1042 static struct vnodeopv_desc procfs_vnodeop_opv_desc = 1043 { &procfs_vnodeop_p, procfs_vnodeop_entries }; 1044 1045 VNODEOP_SET(procfs_vnodeop_opv_desc); 1046