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 1.46 2007/11/20 21:03:50 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/priv.h> 55 #include <sys/signalvar.h> 56 #include <sys/vnode.h> 57 #include <sys/uio.h> 58 #include <sys/mount.h> 59 #include <sys/namei.h> 60 #include <sys/dirent.h> 61 #include <sys/malloc.h> 62 #include <sys/reg.h> 63 #include <vm/vm_zone.h> 64 #include <vfs/procfs/procfs.h> 65 #include <sys/pioctl.h> 66 67 #include <machine/limits.h> 68 69 static int procfs_access (struct vop_access_args *); 70 static int procfs_badop (struct vop_generic_args *); 71 static int procfs_bmap (struct vop_bmap_args *); 72 static int procfs_close (struct vop_close_args *); 73 static int procfs_getattr (struct vop_getattr_args *); 74 static int procfs_inactive (struct vop_inactive_args *); 75 static int procfs_ioctl (struct vop_ioctl_args *); 76 static int procfs_lookup (struct vop_old_lookup_args *); 77 static int procfs_open (struct vop_open_args *); 78 static int procfs_print (struct vop_print_args *); 79 static int procfs_readdir (struct vop_readdir_args *); 80 static int procfs_readlink (struct vop_readlink_args *); 81 static int procfs_reclaim (struct vop_reclaim_args *); 82 static int procfs_setattr (struct vop_setattr_args *); 83 84 static int procfs_readdir_proc(struct vop_readdir_args *); 85 static int procfs_readdir_root(struct vop_readdir_args *); 86 87 /* 88 * procfs vnode operations. 89 */ 90 struct vop_ops procfs_vnode_vops = { 91 .vop_default = vop_defaultop, 92 .vop_access = procfs_access, 93 .vop_advlock = (void *)procfs_badop, 94 .vop_bmap = procfs_bmap, 95 .vop_close = procfs_close, 96 .vop_old_create = (void *)procfs_badop, 97 .vop_getattr = procfs_getattr, 98 .vop_inactive = procfs_inactive, 99 .vop_old_link = (void *)procfs_badop, 100 .vop_old_lookup = procfs_lookup, 101 .vop_old_mkdir = (void *)procfs_badop, 102 .vop_old_mknod = (void *)procfs_badop, 103 .vop_open = procfs_open, 104 .vop_pathconf = vop_stdpathconf, 105 .vop_print = procfs_print, 106 .vop_read = procfs_rw, 107 .vop_readdir = procfs_readdir, 108 .vop_readlink = procfs_readlink, 109 .vop_reclaim = procfs_reclaim, 110 .vop_old_remove = (void *)procfs_badop, 111 .vop_old_rename = (void *)procfs_badop, 112 .vop_old_rmdir = (void *)procfs_badop, 113 .vop_setattr = procfs_setattr, 114 .vop_old_symlink = (void *)procfs_badop, 115 .vop_write = (void *)procfs_rw, 116 .vop_ioctl = procfs_ioctl 117 }; 118 119 120 /* 121 * This is a list of the valid names in the 122 * process-specific sub-directories. It is 123 * used in procfs_lookup and procfs_readdir 124 */ 125 static struct proc_target { 126 u_char pt_type; 127 u_char pt_namlen; 128 char *pt_name; 129 pfstype pt_pfstype; 130 int (*pt_valid) (struct lwp *p); 131 } proc_targets[] = { 132 #define N(s) sizeof(s)-1, s 133 /* name type validp */ 134 { DT_DIR, N("."), Pproc, NULL }, 135 { DT_DIR, N(".."), Proot, NULL }, 136 { DT_REG, N("mem"), Pmem, NULL }, 137 { DT_REG, N("regs"), Pregs, procfs_validregs }, 138 { DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs }, 139 { DT_REG, N("dbregs"), Pdbregs, procfs_validdbregs }, 140 { DT_REG, N("ctl"), Pctl, NULL }, 141 { DT_REG, N("status"), Pstatus, NULL }, 142 { DT_REG, N("note"), Pnote, NULL }, 143 { DT_REG, N("notepg"), Pnotepg, NULL }, 144 { DT_REG, N("map"), Pmap, procfs_validmap }, 145 { DT_REG, N("etype"), Ptype, procfs_validtype }, 146 { DT_REG, N("cmdline"), Pcmdline, NULL }, 147 { DT_REG, N("rlimit"), Prlimit, NULL }, 148 { DT_LNK, N("file"), Pfile, NULL }, 149 #undef N 150 }; 151 static const int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]); 152 153 static pid_t atopid (const char *, u_int); 154 155 /* 156 * set things up for doing i/o on 157 * the pfsnode (vp). (vp) is locked 158 * on entry, and should be left locked 159 * on exit. 160 * 161 * for procfs we don't need to do anything 162 * in particular for i/o. all that is done 163 * is to support exclusive open on process 164 * memory images. 165 * 166 * procfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred, 167 * struct file *a_fp) 168 */ 169 static int 170 procfs_open(struct vop_open_args *ap) 171 { 172 struct pfsnode *pfs = VTOPFS(ap->a_vp); 173 struct proc *p1, *p2; 174 175 p2 = PFIND(pfs->pfs_pid); 176 if (p2 == NULL) 177 return (ENOENT); 178 if (pfs->pfs_pid && !PRISON_CHECK(ap->a_cred, p2->p_ucred)) 179 return (ENOENT); 180 181 switch (pfs->pfs_type) { 182 case Pmem: 183 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) || 184 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) 185 return (EBUSY); 186 187 p1 = curproc; 188 KKASSERT(p1); 189 /* Can't trace a process that's currently exec'ing. */ 190 if ((p2->p_flag & P_INEXEC) != 0) 191 return EAGAIN; 192 if (!CHECKIO(p1, p2) || p_trespass(ap->a_cred, p2->p_ucred)) 193 return (EPERM); 194 195 if (ap->a_mode & FWRITE) 196 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL); 197 198 break; 199 200 default: 201 break; 202 } 203 204 return (vop_stdopen(ap)); 205 } 206 207 /* 208 * close the pfsnode (vp) after doing i/o. 209 * (vp) is not locked on entry or exit. 210 * 211 * nothing to do for procfs other than undo 212 * any exclusive open flag (see _open above). 213 * 214 * procfs_close(struct vnode *a_vp, int a_fflag, struct ucred *a_cred) 215 */ 216 static int 217 procfs_close(struct vop_close_args *ap) 218 { 219 struct pfsnode *pfs = VTOPFS(ap->a_vp); 220 struct proc *p; 221 222 switch (pfs->pfs_type) { 223 case Pmem: 224 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL)) 225 pfs->pfs_flags &= ~(FWRITE|O_EXCL); 226 /* 227 * v_opencount determines the last real close on the vnode. 228 * 229 * If this is the last close, then it checks to see if 230 * the target process has PF_LINGER set in p_pfsflags, 231 * if this is *not* the case, then the process' stop flags 232 * are cleared, and the process is woken up. This is 233 * to help prevent the case where a process has been 234 * told to stop on an event, but then the requesting process 235 * has gone away or forgotten about it. 236 */ 237 if ((ap->a_vp->v_opencount < 2) 238 && (p = pfind(pfs->pfs_pid)) 239 && !(p->p_pfsflags & PF_LINGER)) { 240 p->p_stops = 0; 241 p->p_step = 0; 242 wakeup(&p->p_step); 243 } 244 break; 245 default: 246 break; 247 } 248 249 return (vop_stdclose(ap)); 250 } 251 252 /* 253 * do an ioctl operation on a pfsnode (vp). 254 * (vp) is not locked on entry or exit. 255 */ 256 static int 257 procfs_ioctl(struct vop_ioctl_args *ap) 258 { 259 struct pfsnode *pfs = VTOPFS(ap->a_vp); 260 struct proc *procp; 261 struct proc *p; 262 int error; 263 int signo; 264 struct procfs_status *psp; 265 unsigned char flags; 266 267 procp = pfind(pfs->pfs_pid); 268 if (procp == NULL) 269 return ENOTTY; 270 p = curproc; 271 if (p == NULL) 272 return EINVAL; 273 274 /* Can't trace a process that's currently exec'ing. */ 275 if ((procp->p_flag & P_INEXEC) != 0) 276 return EAGAIN; 277 if (!CHECKIO(p, procp) || p_trespass(ap->a_cred, procp->p_ucred)) 278 return EPERM; 279 280 switch (ap->a_command) { 281 case PIOCBIS: 282 procp->p_stops |= *(unsigned int*)ap->a_data; 283 break; 284 case PIOCBIC: 285 procp->p_stops &= ~*(unsigned int*)ap->a_data; 286 break; 287 case PIOCSFL: 288 /* 289 * NFLAGS is "non-suser_xxx flags" -- currently, only 290 * PFS_ISUGID ("ignore set u/g id"); 291 */ 292 #define NFLAGS (PF_ISUGID) 293 flags = (unsigned char)*(unsigned int*)ap->a_data; 294 if (flags & NFLAGS && (error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0))) 295 return error; 296 procp->p_pfsflags = flags; 297 break; 298 case PIOCGFL: 299 *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags; 300 break; 301 case PIOCSTATUS: 302 psp = (struct procfs_status *)ap->a_data; 303 psp->state = (procp->p_step == 0); 304 psp->flags = procp->p_pfsflags; 305 psp->events = procp->p_stops; 306 if (procp->p_step) { 307 psp->why = procp->p_stype; 308 psp->val = procp->p_xstat; 309 } else { 310 psp->why = psp->val = 0; /* Not defined values */ 311 } 312 break; 313 case PIOCWAIT: 314 psp = (struct procfs_status *)ap->a_data; 315 if (procp->p_step == 0) { 316 error = tsleep(&procp->p_stype, PCATCH, "piocwait", 0); 317 if (error) 318 return error; 319 } 320 psp->state = 1; /* It stopped */ 321 psp->flags = procp->p_pfsflags; 322 psp->events = procp->p_stops; 323 psp->why = procp->p_stype; /* why it stopped */ 324 psp->val = procp->p_xstat; /* any extra info */ 325 break; 326 case PIOCCONT: /* Restart a proc */ 327 if (procp->p_step == 0) 328 return EINVAL; /* Can only start a stopped process */ 329 if ((signo = *(int*)ap->a_data) != 0) { 330 if (signo >= NSIG || signo <= 0) 331 return EINVAL; 332 ksignal(procp, signo); 333 } 334 procp->p_step = 0; 335 wakeup(&procp->p_step); 336 break; 337 default: 338 return (ENOTTY); 339 } 340 return 0; 341 } 342 343 /* 344 * do block mapping for pfsnode (vp). 345 * since we don't use the buffer cache 346 * for procfs this function should never 347 * be called. in any case, it's not clear 348 * what part of the kernel ever makes use 349 * of this function. for sanity, this is the 350 * usual no-op bmap, although returning 351 * (EIO) would be a reasonable alternative. 352 * 353 * XXX mmap assumes buffer cache operation 354 * 355 * procfs_bmap(struct vnode *a_vp, off_t a_loffset, 356 * off_t *a_doffsetp, int *a_runp, int *a_runb) 357 */ 358 static int 359 procfs_bmap(struct vop_bmap_args *ap) 360 { 361 if (ap->a_doffsetp != NULL) 362 *ap->a_doffsetp = ap->a_loffset; 363 if (ap->a_runp != NULL) 364 *ap->a_runp = 0; 365 if (ap->a_runb != NULL) 366 *ap->a_runb = 0; 367 return (0); 368 } 369 370 /* 371 * procfs_inactive is called when the pfsnode 372 * is vrele'd and the reference count goes 373 * to zero. (vp) will be on the vnode free 374 * list, so to get it back vget() must be 375 * used. 376 * 377 * (vp) is locked on entry, but must be unlocked on exit. 378 * 379 * procfs_inactive(struct vnode *a_vp) 380 */ 381 static int 382 procfs_inactive(struct vop_inactive_args *ap) 383 { 384 /*struct vnode *vp = ap->a_vp;*/ 385 386 return (0); 387 } 388 389 /* 390 * _reclaim is called when getnewvnode() 391 * wants to make use of an entry on the vnode 392 * free list. at this time the filesystem needs 393 * to free any private data and remove the node 394 * from any private lists. 395 * 396 * procfs_reclaim(struct vnode *a_vp) 397 */ 398 static int 399 procfs_reclaim(struct vop_reclaim_args *ap) 400 { 401 return (procfs_freevp(ap->a_vp)); 402 } 403 404 /* 405 * _print is used for debugging. 406 * just print a readable description 407 * of (vp). 408 * 409 * procfs_print(struct vnode *a_vp) 410 */ 411 static int 412 procfs_print(struct vop_print_args *ap) 413 { 414 struct pfsnode *pfs = VTOPFS(ap->a_vp); 415 416 kprintf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n", 417 pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags); 418 return (0); 419 } 420 421 /* 422 * generic entry point for unsupported operations 423 */ 424 static int 425 procfs_badop(struct vop_generic_args *ap) 426 { 427 return (EIO); 428 } 429 430 /* 431 * Invent attributes for pfsnode (vp) and store 432 * them in (vap). 433 * Directories lengths are returned as zero since 434 * any real length would require the genuine size 435 * to be computed, and nothing cares anyway. 436 * 437 * this is relatively minimal for procfs. 438 * 439 * procfs_getattr(struct vnode *a_vp, struct vattr *a_vap) 440 */ 441 static int 442 procfs_getattr(struct vop_getattr_args *ap) 443 { 444 struct pfsnode *pfs = VTOPFS(ap->a_vp); 445 struct vattr *vap = ap->a_vap; 446 struct proc *procp; 447 int error; 448 449 /* 450 * First make sure that the process and its credentials 451 * still exist. 452 */ 453 switch (pfs->pfs_type) { 454 case Proot: 455 case Pcurproc: 456 procp = 0; 457 break; 458 459 default: 460 procp = PFIND(pfs->pfs_pid); 461 if (procp == NULL || procp->p_ucred == NULL) 462 return (ENOENT); 463 } 464 465 error = 0; 466 467 /* start by zeroing out the attributes */ 468 VATTR_NULL(vap); 469 470 /* next do all the common fields */ 471 vap->va_type = ap->a_vp->v_type; 472 vap->va_mode = pfs->pfs_mode; 473 vap->va_fileid = pfs->pfs_fileno; 474 vap->va_flags = 0; 475 vap->va_blocksize = PAGE_SIZE; 476 vap->va_bytes = vap->va_size = 0; 477 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; 478 479 /* 480 * Make all times be current TOD. 481 * It would be possible to get the process start 482 * time from the p_stat structure, but there's 483 * no "file creation" time stamp anyway, and the 484 * p_stat structure is not addressible if u. gets 485 * swapped out for that process. 486 */ 487 nanotime(&vap->va_ctime); 488 vap->va_atime = vap->va_mtime = vap->va_ctime; 489 490 /* 491 * If the process has exercised some setuid or setgid 492 * privilege, then rip away read/write permission so 493 * that only root can gain access. 494 */ 495 switch (pfs->pfs_type) { 496 case Pctl: 497 case Pregs: 498 case Pfpregs: 499 case Pdbregs: 500 case Pmem: 501 if (procp->p_flag & P_SUGID) 502 vap->va_mode &= ~((VREAD|VWRITE)| 503 ((VREAD|VWRITE)>>3)| 504 ((VREAD|VWRITE)>>6)); 505 break; 506 default: 507 break; 508 } 509 510 /* 511 * now do the object specific fields 512 * 513 * The size could be set from struct reg, but it's hardly 514 * worth the trouble, and it puts some (potentially) machine 515 * dependent data into this machine-independent code. If it 516 * becomes important then this function should break out into 517 * a per-file stat function in the corresponding .c file. 518 */ 519 520 vap->va_nlink = 1; 521 if (procp) { 522 vap->va_uid = procp->p_ucred->cr_uid; 523 vap->va_gid = procp->p_ucred->cr_gid; 524 } 525 526 switch (pfs->pfs_type) { 527 case Proot: 528 /* 529 * Set nlink to 1 to tell fts(3) we don't actually know. 530 */ 531 vap->va_nlink = 1; 532 vap->va_uid = 0; 533 vap->va_gid = 0; 534 vap->va_size = vap->va_bytes = DEV_BSIZE; 535 break; 536 537 case Pcurproc: { 538 char buf[16]; /* should be enough */ 539 vap->va_uid = 0; 540 vap->va_gid = 0; 541 vap->va_size = vap->va_bytes = 542 ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); 543 break; 544 } 545 546 case Pproc: 547 vap->va_nlink = nproc_targets; 548 vap->va_size = vap->va_bytes = DEV_BSIZE; 549 break; 550 551 case Pfile: { 552 char *fullpath, *freepath; 553 error = vn_fullpath(procp, NULL, &fullpath, &freepath); 554 if (error == 0) { 555 vap->va_size = strlen(fullpath); 556 kfree(freepath, M_TEMP); 557 } else { 558 vap->va_size = sizeof("unknown") - 1; 559 error = 0; 560 } 561 vap->va_bytes = vap->va_size; 562 break; 563 } 564 565 case Pmem: 566 /* 567 * If we denied owner access earlier, then we have to 568 * change the owner to root - otherwise 'ps' and friends 569 * will break even though they are setgid kmem. *SIGH* 570 */ 571 if (procp->p_flag & P_SUGID) 572 vap->va_uid = 0; 573 else 574 vap->va_uid = procp->p_ucred->cr_uid; 575 break; 576 577 case Pregs: 578 vap->va_bytes = vap->va_size = sizeof(struct reg); 579 break; 580 581 case Pfpregs: 582 vap->va_bytes = vap->va_size = sizeof(struct fpreg); 583 break; 584 585 case Pdbregs: 586 vap->va_bytes = vap->va_size = sizeof(struct dbreg); 587 break; 588 589 case Ptype: 590 case Pmap: 591 case Pctl: 592 case Pstatus: 593 case Pnote: 594 case Pnotepg: 595 case Pcmdline: 596 case Prlimit: 597 break; 598 599 default: 600 panic("procfs_getattr"); 601 } 602 603 return (error); 604 } 605 606 /* 607 * procfs_setattr(struct vnode *a_vp, struct vattr *a_vap, 608 * struct ucred *a_cred) 609 */ 610 static int 611 procfs_setattr(struct vop_setattr_args *ap) 612 { 613 if (ap->a_vap->va_flags != VNOVAL) 614 return (EOPNOTSUPP); 615 616 /* 617 * just fake out attribute setting 618 * it's not good to generate an error 619 * return, otherwise things like creat() 620 * will fail when they try to set the 621 * file length to 0. worse, this means 622 * that echo $note > /proc/$pid/note will fail. 623 */ 624 625 return (0); 626 } 627 628 /* 629 * implement access checking. 630 * 631 * procfs_access(struct vnode *a_vp, int a_mode, struct ucred *a_cred) 632 */ 633 static int 634 procfs_access(struct vop_access_args *ap) 635 { 636 struct vattr vattr; 637 int error; 638 639 error = VOP_GETATTR(ap->a_vp, &vattr); 640 if (!error) 641 error = vop_helper_access(ap, vattr.va_uid, vattr.va_gid, 642 vattr.va_mode, 0); 643 return (error); 644 } 645 646 /* 647 * lookup. this is incredibly complicated in the general case, however 648 * for most pseudo-filesystems very little needs to be done. 649 * 650 * procfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp, 651 * struct componentname *a_cnp) 652 */ 653 static int 654 procfs_lookup(struct vop_old_lookup_args *ap) 655 { 656 struct componentname *cnp = ap->a_cnp; 657 struct vnode **vpp = ap->a_vpp; 658 struct vnode *dvp = ap->a_dvp; 659 char *pname = cnp->cn_nameptr; 660 /* struct proc *curp = cnp->cn_proc; */ 661 struct proc_target *pt; 662 pid_t pid; 663 struct pfsnode *pfs; 664 struct proc *p; 665 struct lwp *lp; 666 int i; 667 int error; 668 669 *vpp = NULL; 670 671 if (cnp->cn_nameiop == NAMEI_DELETE || cnp->cn_nameiop == NAMEI_RENAME) 672 return (EROFS); 673 674 error = 0; 675 if (cnp->cn_namelen == 1 && *pname == '.') { 676 *vpp = dvp; 677 vref(*vpp); 678 goto out; 679 } 680 681 pfs = VTOPFS(dvp); 682 switch (pfs->pfs_type) { 683 case Proot: 684 if (cnp->cn_flags & CNP_ISDOTDOT) 685 return (EIO); 686 687 if (CNEQ(cnp, "curproc", 7)) { 688 error = procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc); 689 goto out; 690 } 691 692 pid = atopid(pname, cnp->cn_namelen); 693 if (pid == NO_PID) 694 break; 695 696 p = PFIND(pid); 697 if (p == NULL) 698 break; 699 700 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred)) 701 break; 702 703 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 && 704 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid) 705 break; 706 707 error = procfs_allocvp(dvp->v_mount, vpp, pid, Pproc); 708 goto out; 709 710 case Pproc: 711 if (cnp->cn_flags & CNP_ISDOTDOT) { 712 error = procfs_root(dvp->v_mount, vpp); 713 goto out; 714 } 715 716 p = PFIND(pfs->pfs_pid); 717 if (p == NULL) 718 break; 719 /* XXX lwp */ 720 lp = FIRST_LWP_IN_PROC(p); 721 722 if (!PRISON_CHECK(ap->a_cnp->cn_cred, p->p_ucred)) 723 break; 724 725 if (ps_showallprocs == 0 && ap->a_cnp->cn_cred->cr_uid != 0 && 726 ap->a_cnp->cn_cred->cr_uid != p->p_ucred->cr_uid) 727 break; 728 729 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) { 730 if (cnp->cn_namelen == pt->pt_namlen && 731 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 && 732 (pt->pt_valid == NULL || (*pt->pt_valid)(lp))) 733 goto found; 734 } 735 break; 736 found: 737 error = procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid, 738 pt->pt_pfstype); 739 goto out; 740 741 default: 742 error = ENOTDIR; 743 goto out; 744 } 745 if (cnp->cn_nameiop == NAMEI_LOOKUP) 746 error = ENOENT; 747 else 748 error = EROFS; 749 /* 750 * If no error occured *vpp will hold a referenced locked vnode. 751 * dvp was passed to us locked and *vpp must be returned locked. 752 * If *vpp != dvp then we should unlock dvp if (1) this is not the 753 * last component or (2) CNP_LOCKPARENT is not set. 754 */ 755 out: 756 if (error == 0 && *vpp != dvp) { 757 if ((cnp->cn_flags & CNP_LOCKPARENT) == 0) { 758 cnp->cn_flags |= CNP_PDIRUNLOCK; 759 vn_unlock(dvp); 760 } 761 } 762 return (error); 763 } 764 765 /* 766 * Does this process have a text file? 767 */ 768 int 769 procfs_validfile(struct lwp *lp) 770 { 771 return (procfs_findtextvp(lp->lwp_proc) != NULLVP); 772 } 773 774 /* 775 * readdir() returns directory entries from pfsnode (vp). 776 * 777 * We generate just one directory entry at a time, as it would probably 778 * not pay off to buffer several entries locally to save uiomove calls. 779 * 780 * procfs_readdir(struct vnode *a_vp, struct uio *a_uio, struct ucred *a_cred, 781 * int *a_eofflag, int *a_ncookies, off_t **a_cookies) 782 */ 783 static int 784 procfs_readdir(struct vop_readdir_args *ap) 785 { 786 struct pfsnode *pfs; 787 int error; 788 789 if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX) 790 return (EINVAL); 791 if ((error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY)) != 0) 792 return (error); 793 pfs = VTOPFS(ap->a_vp); 794 795 switch (pfs->pfs_type) { 796 case Pproc: 797 /* 798 * this is for the process-specific sub-directories. 799 * all that is needed to is copy out all the entries 800 * from the procent[] table (top of this file). 801 */ 802 error = procfs_readdir_proc(ap); 803 break; 804 case Proot: 805 /* 806 * this is for the root of the procfs filesystem 807 * what is needed is a special entry for "curproc" 808 * followed by an entry for each process on allproc 809 */ 810 error = procfs_readdir_root(ap); 811 break; 812 default: 813 error = ENOTDIR; 814 break; 815 } 816 817 vn_unlock(ap->a_vp); 818 return (error); 819 } 820 821 static int 822 procfs_readdir_proc(struct vop_readdir_args *ap) 823 { 824 struct pfsnode *pfs; 825 int error, i, retval; 826 struct proc *p; 827 struct lwp *lp; 828 struct proc_target *pt; 829 struct uio *uio = ap->a_uio; 830 831 pfs = VTOPFS(ap->a_vp); 832 p = PFIND(pfs->pfs_pid); 833 if (p == NULL) 834 return(0); 835 if (!PRISON_CHECK(ap->a_cred, p->p_ucred)) 836 return(0); 837 /* XXX lwp */ 838 lp = FIRST_LWP_IN_PROC(p); 839 840 error = 0; 841 i = (int)uio->uio_offset; 842 if (i < 0) 843 return (EINVAL); 844 845 for (pt = &proc_targets[i]; 846 !error && uio->uio_resid > 0 && i < nproc_targets; pt++, i++) { 847 if (pt->pt_valid && (*pt->pt_valid)(lp) == 0) 848 continue; 849 850 retval = vop_write_dirent(&error, uio, 851 PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype), pt->pt_type, 852 pt->pt_namlen, pt->pt_name); 853 if (retval) 854 break; 855 } 856 857 uio->uio_offset = (off_t)i; 858 859 return(0); 860 } 861 862 struct procfs_readdir_root_info { 863 int error; 864 int i; 865 int pcnt; 866 struct uio *uio; 867 struct ucred *cred; 868 }; 869 870 static int procfs_readdir_root_callback(struct proc *p, void *data); 871 872 static int 873 procfs_readdir_root(struct vop_readdir_args *ap) 874 { 875 struct procfs_readdir_root_info info; 876 struct uio *uio = ap->a_uio; 877 int res; 878 879 info.error = 0; 880 info.i = (int)uio->uio_offset; 881 882 if (info.i < 0) 883 return (EINVAL); 884 885 info.pcnt = 0; 886 info.uio = uio; 887 info.cred = ap->a_cred; 888 while (info.pcnt < 3) { 889 res = procfs_readdir_root_callback(NULL, &info); 890 if (res < 0) 891 break; 892 } 893 if (res >= 0) 894 allproc_scan(procfs_readdir_root_callback, &info); 895 uio->uio_offset = (off_t)info.i; 896 897 return (info.error); 898 } 899 900 static int 901 procfs_readdir_root_callback(struct proc *p, void *data) 902 { 903 struct procfs_readdir_root_info *info = data; 904 struct uio *uio; 905 int retval; 906 ino_t d_ino; 907 const char *d_name; 908 char d_name_pid[20]; 909 size_t d_namlen; 910 uint8_t d_type; 911 912 uio = info->uio; 913 914 if (uio->uio_resid <= 0 || info->error) 915 return(-1); 916 917 switch (info->pcnt) { 918 case 0: /* `.' */ 919 d_ino = PROCFS_FILENO(0, Proot); 920 d_name = "."; 921 d_namlen = 1; 922 d_type = DT_DIR; 923 break; 924 case 1: /* `..' */ 925 d_ino = PROCFS_FILENO(0, Proot); 926 d_name = ".."; 927 d_namlen = 2; 928 d_type = DT_DIR; 929 break; 930 931 case 2: 932 d_ino = PROCFS_FILENO(0, Pcurproc); 933 d_namlen = 7; 934 d_name = "curproc"; 935 d_type = DT_LNK; 936 break; 937 938 939 default: 940 if (!PRISON_CHECK(info->cred, p->p_ucred)) 941 return(0); 942 if (ps_showallprocs == 0 && 943 info->cred->cr_uid != 0 && 944 info->cred->cr_uid != p->p_ucred->cr_uid) { 945 return(0); 946 } 947 948 /* 949 * Skip entries we have already returned (optimization) 950 */ 951 if (info->pcnt < info->i) { 952 ++info->pcnt; 953 return(0); 954 } 955 956 d_ino = PROCFS_FILENO(p->p_pid, Pproc); 957 d_namlen = ksnprintf(d_name_pid, sizeof(d_name_pid), 958 "%ld", (long)p->p_pid); 959 d_name = d_name_pid; 960 d_type = DT_DIR; 961 break; 962 } 963 964 /* 965 * Skip entries we have already returned (optimization) 966 */ 967 if (info->pcnt < info->i) { 968 ++info->pcnt; 969 return(0); 970 } 971 972 retval = vop_write_dirent(&info->error, uio, 973 d_ino, d_type, d_namlen, d_name); 974 if (retval) 975 return(-1); 976 ++info->pcnt; 977 ++info->i; 978 return(0); 979 } 980 981 /* 982 * readlink reads the link of `curproc' or `file' 983 */ 984 static int 985 procfs_readlink(struct vop_readlink_args *ap) 986 { 987 char buf[16]; /* should be enough */ 988 struct proc *procp; 989 struct vnode *vp = ap->a_vp; 990 struct pfsnode *pfs = VTOPFS(vp); 991 char *fullpath, *freepath; 992 int error, len; 993 994 switch (pfs->pfs_type) { 995 case Pcurproc: 996 if (pfs->pfs_fileno != PROCFS_FILENO(0, Pcurproc)) 997 return (EINVAL); 998 999 len = ksnprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); 1000 1001 return (uiomove(buf, len, ap->a_uio)); 1002 /* 1003 * There _should_ be no way for an entire process to disappear 1004 * from under us... 1005 */ 1006 case Pfile: 1007 procp = PFIND(pfs->pfs_pid); 1008 if (procp == NULL || procp->p_ucred == NULL) { 1009 kprintf("procfs_readlink: pid %d disappeared\n", 1010 pfs->pfs_pid); 1011 return (uiomove("unknown", sizeof("unknown") - 1, 1012 ap->a_uio)); 1013 } 1014 error = vn_fullpath(procp, NULL, &fullpath, &freepath); 1015 if (error != 0) 1016 return (uiomove("unknown", sizeof("unknown") - 1, 1017 ap->a_uio)); 1018 error = uiomove(fullpath, strlen(fullpath), ap->a_uio); 1019 kfree(freepath, M_TEMP); 1020 return (error); 1021 default: 1022 return (EINVAL); 1023 } 1024 } 1025 1026 /* 1027 * convert decimal ascii to pid_t 1028 */ 1029 static pid_t 1030 atopid(const char *b, u_int len) 1031 { 1032 pid_t p = 0; 1033 1034 while (len--) { 1035 char c = *b++; 1036 if (c < '0' || c > '9') 1037 return (NO_PID); 1038 p = 10 * p + (c - '0'); 1039 if (p > PID_MAX) 1040 return (NO_PID); 1041 } 1042 1043 return (p); 1044 } 1045 1046