1 /* 2 * Copyright (c) 2004 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 /* 35 * nlookup() is the 'new' namei interface. Rather then return directory and 36 * leaf vnodes (in various lock states) the new interface instead deals in 37 * namecache records. Namecache records may represent both a positive or 38 * a negative hit. The namespace is locked via the namecache record instead 39 * of via the vnode, and only the leaf namecache record (representing the 40 * filename) needs to be locked. 41 * 42 * This greatly improves filesystem parallelism and is a huge simplification 43 * of the API verses the old vnode locking / namei scheme. 44 * 45 * Filesystems must actively control the caching aspects of the namecache, 46 * and since namecache pointers are used as handles they are non-optional 47 * even for filesystems which do not generally wish to cache things. It is 48 * intended that a separate cache coherency API will be constructed to handle 49 * these issues. 50 */ 51 52 #include "opt_ktrace.h" 53 54 #include <sys/param.h> 55 #include <sys/systm.h> 56 #include <sys/kernel.h> 57 #include <sys/vnode.h> 58 #include <sys/mount.h> 59 #include <sys/filedesc.h> 60 #include <sys/proc.h> 61 #include <sys/namei.h> 62 #include <sys/nlookup.h> 63 #include <sys/malloc.h> 64 #include <sys/stat.h> 65 #include <sys/objcache.h> 66 #include <sys/file.h> 67 68 #ifdef KTRACE 69 #include <sys/ktrace.h> 70 #endif 71 72 static int naccess(struct nchandle *nch, int vmode, struct ucred *cred, 73 int *stickyp); 74 75 /* 76 * Initialize a nlookup() structure, early error return for copyin faults 77 * or a degenerate empty string (which is not allowed). 78 * 79 * The first process proc0's credentials are used if the calling thread 80 * is not associated with a process context. 81 * 82 * MPSAFE 83 */ 84 int 85 nlookup_init(struct nlookupdata *nd, 86 const char *path, enum uio_seg seg, int flags) 87 { 88 size_t pathlen; 89 struct proc *p; 90 thread_t td; 91 int error; 92 93 td = curthread; 94 p = td->td_proc; 95 96 /* 97 * note: the pathlen set by copy*str() includes the terminating \0. 98 */ 99 bzero(nd, sizeof(struct nlookupdata)); 100 nd->nl_path = objcache_get(namei_oc, M_WAITOK); 101 nd->nl_flags |= NLC_HASBUF; 102 if (seg == UIO_SYSSPACE) 103 error = copystr(path, nd->nl_path, MAXPATHLEN, &pathlen); 104 else 105 error = copyinstr(path, nd->nl_path, MAXPATHLEN, &pathlen); 106 107 /* 108 * Don't allow empty pathnames. 109 * POSIX.1 requirement: "" is not a vaild file name. 110 */ 111 if (error == 0 && pathlen <= 1) 112 error = ENOENT; 113 114 if (error == 0) { 115 if (p && p->p_fd) { 116 cache_copy(&p->p_fd->fd_ncdir, &nd->nl_nch); 117 cache_copy(&p->p_fd->fd_nrdir, &nd->nl_rootnch); 118 if (p->p_fd->fd_njdir.ncp) 119 cache_copy(&p->p_fd->fd_njdir, &nd->nl_jailnch); 120 nd->nl_cred = crhold(p->p_ucred); 121 } else { 122 cache_copy(&rootnch, &nd->nl_nch); 123 cache_copy(&nd->nl_nch, &nd->nl_rootnch); 124 cache_copy(&nd->nl_nch, &nd->nl_jailnch); 125 nd->nl_cred = crhold(proc0.p_ucred); 126 } 127 nd->nl_td = td; 128 nd->nl_flags |= flags; 129 } else { 130 nlookup_done(nd); 131 } 132 return(error); 133 } 134 135 136 /* 137 * nlookup_init() for "at" family of syscalls. 138 * 139 * Works similarly to nlookup_init() but if path is relative and fd is not 140 * AT_FDCWD, path is interpreted relative to the directory pointed to by fd. 141 * In this case, the file entry pointed to by fd is ref'ed and returned in 142 * *fpp. 143 * 144 * If the call succeeds, nlookup_done_at() must be called to clean-up the nd 145 * and release the ref to the file entry. 146 */ 147 int 148 nlookup_init_at(struct nlookupdata *nd, struct file **fpp, int fd, 149 const char *path, enum uio_seg seg, int flags) 150 { 151 struct thread *td = curthread; 152 struct proc *p = td->td_proc; 153 struct file* fp; 154 struct vnode *vp; 155 int error; 156 157 *fpp = NULL; 158 159 if ((error = nlookup_init(nd, path, seg, flags)) != 0) { 160 return (error); 161 } 162 163 if (nd->nl_path[0] != '/' && fd != AT_FDCWD) { 164 if ((error = holdvnode(p->p_fd, fd, &fp)) != 0) 165 goto done; 166 vp = (struct vnode*)fp->f_data; 167 if (vp->v_type != VDIR || fp->f_nchandle.ncp == NULL) { 168 fdrop(fp); 169 fp = NULL; 170 error = ENOTDIR; 171 goto done; 172 } 173 cache_drop(&nd->nl_nch); 174 cache_copy(&fp->f_nchandle, &nd->nl_nch); 175 *fpp = fp; 176 } 177 178 179 done: 180 if (error) 181 nlookup_done(nd); 182 return (error); 183 184 } 185 186 /* 187 * This works similarly to nlookup_init() but does not assume a process 188 * context. rootnch is always chosen for the root directory and the cred 189 * and starting directory are supplied in arguments. 190 */ 191 int 192 nlookup_init_raw(struct nlookupdata *nd, 193 const char *path, enum uio_seg seg, int flags, 194 struct ucred *cred, struct nchandle *ncstart) 195 { 196 size_t pathlen; 197 thread_t td; 198 int error; 199 200 td = curthread; 201 202 bzero(nd, sizeof(struct nlookupdata)); 203 nd->nl_path = objcache_get(namei_oc, M_WAITOK); 204 nd->nl_flags |= NLC_HASBUF; 205 if (seg == UIO_SYSSPACE) 206 error = copystr(path, nd->nl_path, MAXPATHLEN, &pathlen); 207 else 208 error = copyinstr(path, nd->nl_path, MAXPATHLEN, &pathlen); 209 210 /* 211 * Don't allow empty pathnames. 212 * POSIX.1 requirement: "" is not a vaild file name. 213 */ 214 if (error == 0 && pathlen <= 1) 215 error = ENOENT; 216 217 if (error == 0) { 218 cache_copy(ncstart, &nd->nl_nch); 219 cache_copy(&rootnch, &nd->nl_rootnch); 220 cache_copy(&rootnch, &nd->nl_jailnch); 221 nd->nl_cred = crhold(cred); 222 nd->nl_td = td; 223 nd->nl_flags |= flags; 224 } else { 225 nlookup_done(nd); 226 } 227 return(error); 228 } 229 230 /* 231 * This works similarly to nlookup_init_raw() but does not rely 232 * on rootnch being initialized yet. 233 */ 234 int 235 nlookup_init_root(struct nlookupdata *nd, 236 const char *path, enum uio_seg seg, int flags, 237 struct ucred *cred, struct nchandle *ncstart, 238 struct nchandle *ncroot) 239 { 240 size_t pathlen; 241 thread_t td; 242 int error; 243 244 td = curthread; 245 246 bzero(nd, sizeof(struct nlookupdata)); 247 nd->nl_path = objcache_get(namei_oc, M_WAITOK); 248 nd->nl_flags |= NLC_HASBUF; 249 if (seg == UIO_SYSSPACE) 250 error = copystr(path, nd->nl_path, MAXPATHLEN, &pathlen); 251 else 252 error = copyinstr(path, nd->nl_path, MAXPATHLEN, &pathlen); 253 254 /* 255 * Don't allow empty pathnames. 256 * POSIX.1 requirement: "" is not a vaild file name. 257 */ 258 if (error == 0 && pathlen <= 1) 259 error = ENOENT; 260 261 if (error == 0) { 262 cache_copy(ncstart, &nd->nl_nch); 263 cache_copy(ncroot, &nd->nl_rootnch); 264 cache_copy(ncroot, &nd->nl_jailnch); 265 nd->nl_cred = crhold(cred); 266 nd->nl_td = td; 267 nd->nl_flags |= flags; 268 } else { 269 nlookup_done(nd); 270 } 271 return(error); 272 } 273 274 /* 275 * Set a different credential; this credential will be used by future 276 * operations performed on nd.nl_open_vp and nlookupdata structure. 277 */ 278 void 279 nlookup_set_cred(struct nlookupdata *nd, struct ucred *cred) 280 { 281 KKASSERT(nd->nl_cred != NULL); 282 283 if (nd->nl_cred != cred) { 284 cred = crhold(cred); 285 crfree(nd->nl_cred); 286 nd->nl_cred = cred; 287 } 288 } 289 290 /* 291 * Cleanup a nlookupdata structure after we are through with it. This may 292 * be called on any nlookupdata structure initialized with nlookup_init(). 293 * Calling nlookup_done() is mandatory in all cases except where nlookup_init() 294 * returns an error, even if as a consumer you believe you have taken all 295 * dynamic elements out of the nlookupdata structure. 296 */ 297 void 298 nlookup_done(struct nlookupdata *nd) 299 { 300 if (nd->nl_nch.ncp) { 301 if (nd->nl_flags & NLC_NCPISLOCKED) { 302 nd->nl_flags &= ~NLC_NCPISLOCKED; 303 cache_unlock(&nd->nl_nch); 304 } 305 cache_drop(&nd->nl_nch); /* NULL's out the nch */ 306 } 307 if (nd->nl_rootnch.ncp) 308 cache_drop(&nd->nl_rootnch); 309 if (nd->nl_jailnch.ncp) 310 cache_drop(&nd->nl_jailnch); 311 if ((nd->nl_flags & NLC_HASBUF) && nd->nl_path) { 312 objcache_put(namei_oc, nd->nl_path); 313 nd->nl_path = NULL; 314 } 315 if (nd->nl_cred) { 316 crfree(nd->nl_cred); 317 nd->nl_cred = NULL; 318 } 319 if (nd->nl_open_vp) { 320 if (nd->nl_flags & NLC_LOCKVP) { 321 vn_unlock(nd->nl_open_vp); 322 nd->nl_flags &= ~NLC_LOCKVP; 323 } 324 vn_close(nd->nl_open_vp, nd->nl_vp_fmode, NULL); 325 nd->nl_open_vp = NULL; 326 } 327 if (nd->nl_dvp) { 328 vrele(nd->nl_dvp); 329 nd->nl_dvp = NULL; 330 } 331 nd->nl_flags = 0; /* clear remaining flags (just clear everything) */ 332 } 333 334 /* 335 * Works similarly to nlookup_done() when nd initialized with 336 * nlookup_init_at(). 337 */ 338 void 339 nlookup_done_at(struct nlookupdata *nd, struct file *fp) 340 { 341 nlookup_done(nd); 342 if (fp != NULL) 343 fdrop(fp); 344 } 345 346 void 347 nlookup_zero(struct nlookupdata *nd) 348 { 349 bzero(nd, sizeof(struct nlookupdata)); 350 } 351 352 /* 353 * Simple all-in-one nlookup. Returns a locked namecache structure or NULL 354 * if an error occured. 355 * 356 * Note that the returned ncp is not checked for permissions, though VEXEC 357 * is checked on the directory path leading up to the result. The caller 358 * must call naccess() to check the permissions of the returned leaf. 359 */ 360 struct nchandle 361 nlookup_simple(const char *str, enum uio_seg seg, 362 int niflags, int *error) 363 { 364 struct nlookupdata nd; 365 struct nchandle nch; 366 367 *error = nlookup_init(&nd, str, seg, niflags); 368 if (*error == 0) { 369 if ((*error = nlookup(&nd)) == 0) { 370 nch = nd.nl_nch; /* keep hold ref from structure */ 371 cache_zero(&nd.nl_nch); /* and NULL out */ 372 } else { 373 cache_zero(&nch); 374 } 375 nlookup_done(&nd); 376 } else { 377 cache_zero(&nch); 378 } 379 return(nch); 380 } 381 382 /* 383 * Returns non-zero if the path element is the last element 384 */ 385 static 386 int 387 islastelement(const char *ptr) 388 { 389 while (*ptr == '/') 390 ++ptr; 391 return (*ptr == 0); 392 } 393 394 /* 395 * Returns non-zero if we need to lock the namecache element 396 * exclusively. Unless otherwise requested by NLC_SHAREDLOCK, 397 * the last element of the namecache lookup will be locked 398 * exclusively. 399 * 400 * NOTE: Even if we return on-zero, an unresolved namecache record 401 * will always be locked exclusively. 402 */ 403 static __inline 404 int 405 wantsexcllock(struct nlookupdata *nd, const char *ptr) 406 { 407 if ((nd->nl_flags & NLC_SHAREDLOCK) == 0) 408 return(islastelement(ptr)); 409 return(0); 410 } 411 412 413 /* 414 * Do a generic nlookup. Note that the passed nd is not nlookup_done()'d 415 * on return, even if an error occurs. If no error occurs or NLC_CREATE 416 * is flagged and ENOENT is returned, then the returned nl_nch is always 417 * referenced and locked exclusively. 418 * 419 * WARNING: For any general error other than ENOENT w/NLC_CREATE, the 420 * the resulting nl_nch may or may not be locked and if locked 421 * might be locked either shared or exclusive. 422 * 423 * Intermediate directory elements, including the current directory, require 424 * execute (search) permission. nlookup does not examine the access 425 * permissions on the returned element. 426 * 427 * If NLC_CREATE is set the last directory must allow node creation, 428 * and an error code of 0 will be returned for a non-existant 429 * target (not ENOENT). 430 * 431 * If NLC_RENAME_DST is set the last directory mut allow node deletion, 432 * plus the sticky check is made, and an error code of 0 will be returned 433 * for a non-existant target (not ENOENT). 434 * 435 * If NLC_DELETE is set the last directory mut allow node deletion, 436 * plus the sticky check is made. 437 * 438 * If NLC_REFDVP is set nd->nl_dvp will be set to the directory vnode 439 * of the returned entry. The vnode will be referenced, but not locked, 440 * and will be released by nlookup_done() along with everything else. 441 * 442 * NOTE: As an optimization we attempt to obtain a shared namecache lock 443 * on any intermediate elements. On success, the returned element 444 * is ALWAYS locked exclusively. 445 */ 446 int 447 nlookup(struct nlookupdata *nd) 448 { 449 globaldata_t gd = mycpu; 450 struct nlcomponent nlc; 451 struct nchandle nch; 452 struct nchandle par; 453 struct nchandle nctmp; 454 struct mount *mp; 455 struct vnode *hvp; /* hold to prevent recyclement */ 456 int wasdotordotdot; 457 char *ptr; 458 int error; 459 int len; 460 int dflags; 461 int hit = 1; 462 463 #ifdef KTRACE 464 if (KTRPOINT(nd->nl_td, KTR_NAMEI)) 465 ktrnamei(nd->nl_td->td_lwp, nd->nl_path); 466 #endif 467 bzero(&nlc, sizeof(nlc)); 468 469 /* 470 * Setup for the loop. The current working namecache element is 471 * always at least referenced. We lock it as required, but always 472 * return a locked, resolved namecache entry. 473 */ 474 nd->nl_loopcnt = 0; 475 if (nd->nl_dvp) { 476 vrele(nd->nl_dvp); 477 nd->nl_dvp = NULL; 478 } 479 ptr = nd->nl_path; 480 481 /* 482 * Loop on the path components. At the top of the loop nd->nl_nch 483 * is ref'd and unlocked and represents our current position. 484 */ 485 for (;;) { 486 /* 487 * Make sure nl_nch is locked so we can access the vnode, resolution 488 * state, etc. 489 */ 490 if ((nd->nl_flags & NLC_NCPISLOCKED) == 0) { 491 nd->nl_flags |= NLC_NCPISLOCKED; 492 cache_lock_maybe_shared(&nd->nl_nch, wantsexcllock(nd, ptr)); 493 } 494 495 /* 496 * Check if the root directory should replace the current 497 * directory. This is done at the start of a translation 498 * or after a symbolic link has been found. In other cases 499 * ptr will never be pointing at a '/'. 500 */ 501 if (*ptr == '/') { 502 do { 503 ++ptr; 504 } while (*ptr == '/'); 505 cache_unlock(&nd->nl_nch); 506 cache_get_maybe_shared(&nd->nl_rootnch, &nch, 507 wantsexcllock(nd, ptr)); 508 cache_drop(&nd->nl_nch); 509 nd->nl_nch = nch; /* remains locked */ 510 511 /* 512 * Fast-track termination. There is no parent directory of 513 * the root in the same mount from the point of view of 514 * the caller so return EACCES if NLC_REFDVP is specified, 515 * and EEXIST if NLC_CREATE is also specified. 516 * e.g. 'rmdir /' or 'mkdir /' are not allowed. 517 */ 518 if (*ptr == 0) { 519 if (nd->nl_flags & NLC_REFDVP) 520 error = (nd->nl_flags & NLC_CREATE) ? EEXIST : EACCES; 521 else 522 error = 0; 523 break; 524 } 525 continue; 526 } 527 528 /* 529 * Check directory search permissions (nd->nl_nch is locked & refd) 530 */ 531 dflags = 0; 532 error = naccess(&nd->nl_nch, NLC_EXEC, nd->nl_cred, &dflags); 533 if (error) 534 break; 535 536 /* 537 * Extract the path component. Path components are limited to 538 * 255 characters. 539 */ 540 nlc.nlc_nameptr = ptr; 541 while (*ptr && *ptr != '/') 542 ++ptr; 543 nlc.nlc_namelen = ptr - nlc.nlc_nameptr; 544 if (nlc.nlc_namelen >= 256) { 545 error = ENAMETOOLONG; 546 break; 547 } 548 549 /* 550 * Lookup the path component in the cache, creating an unresolved 551 * entry if necessary. We have to handle "." and ".." as special 552 * cases. 553 * 554 * When handling ".." we have to detect a traversal back through a 555 * mount point. If we are at the root, ".." just returns the root. 556 * 557 * When handling "." or ".." we also have to recalculate dflags 558 * since our dflags will be for some sub-directory instead of the 559 * parent dir. 560 * 561 * This subsection returns a locked, refd 'nch' unless it errors out, 562 * and an unlocked but still ref'd nd->nl_nch. 563 * 564 * The namecache topology is not allowed to be disconnected, so 565 * encountering a NULL parent will generate EINVAL. This typically 566 * occurs when a directory is removed out from under a process. 567 * 568 * WARNING! The unlocking of nd->nl_nch is sensitive code. 569 */ 570 KKASSERT(nd->nl_flags & NLC_NCPISLOCKED); 571 572 if (nlc.nlc_namelen == 1 && nlc.nlc_nameptr[0] == '.') { 573 cache_unlock(&nd->nl_nch); 574 nd->nl_flags &= ~NLC_NCPISLOCKED; 575 cache_get_maybe_shared(&nd->nl_nch, &nch, wantsexcllock(nd, ptr)); 576 wasdotordotdot = 1; 577 } else if (nlc.nlc_namelen == 2 && 578 nlc.nlc_nameptr[0] == '.' && nlc.nlc_nameptr[1] == '.') { 579 if (nd->nl_nch.mount == nd->nl_rootnch.mount && 580 nd->nl_nch.ncp == nd->nl_rootnch.ncp 581 ) { 582 /* 583 * ".." at the root returns the root 584 */ 585 cache_unlock(&nd->nl_nch); 586 nd->nl_flags &= ~NLC_NCPISLOCKED; 587 cache_get_maybe_shared(&nd->nl_nch, &nch, 588 wantsexcllock(nd, ptr)); 589 } else { 590 /* 591 * Locate the parent ncp. If we are at the root of a 592 * filesystem mount we have to skip to the mounted-on 593 * point in the underlying filesystem. 594 * 595 * Expect the parent to always be good since the 596 * mountpoint doesn't go away. XXX hack. cache_get() 597 * requires the ncp to already have a ref as a safety. 598 * 599 * However, a process which has been broken out of a chroot 600 * will wind up with a NULL parent if it tries to '..' above 601 * the real root, deal with the case. Note that this does 602 * not protect us from a jail breakout, it just stops a panic 603 * if the jail-broken process tries to '..' past the real 604 * root. 605 */ 606 nctmp = nd->nl_nch; 607 while (nctmp.ncp == nctmp.mount->mnt_ncmountpt.ncp) { 608 nctmp = nctmp.mount->mnt_ncmounton; 609 if (nctmp.ncp == NULL) 610 break; 611 } 612 if (nctmp.ncp == NULL) { 613 if (curthread->td_proc) { 614 kprintf("vfs_nlookup: '..' traverse broke " 615 "jail: pid %d (%s)\n", 616 curthread->td_proc->p_pid, 617 curthread->td_comm); 618 } 619 nctmp = nd->nl_rootnch; 620 } else { 621 nctmp.ncp = nctmp.ncp->nc_parent; 622 } 623 cache_hold(&nctmp); 624 cache_unlock(&nd->nl_nch); 625 nd->nl_flags &= ~NLC_NCPISLOCKED; 626 cache_get_maybe_shared(&nctmp, &nch, wantsexcllock(nd, ptr)); 627 cache_drop(&nctmp); /* NOTE: zero's nctmp */ 628 } 629 wasdotordotdot = 2; 630 } else { 631 /* 632 * Must unlock nl_nch when traversing down the path. However, 633 * the child ncp has not yet been found/created and the parent's 634 * child list might be empty. Thus releasing the lock can 635 * allow a race whereby the parent ncp's vnode is recycled. 636 * This case can occur especially when maxvnodes is set very low. 637 * 638 * We need the parent's ncp to remain resolved for all normal 639 * filesystem activities, so we vhold() the vp during the lookup 640 * to prevent recyclement due to vnlru / maxvnodes. 641 * 642 * If we race an unlink or rename the ncp might be marked 643 * DESTROYED after resolution, requiring a retry. 644 */ 645 if ((hvp = nd->nl_nch.ncp->nc_vp) != NULL) 646 vhold(hvp); 647 cache_unlock(&nd->nl_nch); 648 nd->nl_flags &= ~NLC_NCPISLOCKED; 649 error = cache_nlookup_maybe_shared(&nd->nl_nch, &nlc, 650 wantsexcllock(nd, ptr), &nch); 651 if (error == EWOULDBLOCK) { 652 nch = cache_nlookup(&nd->nl_nch, &nlc); 653 if (nch.ncp->nc_flag & NCF_UNRESOLVED) 654 hit = 0; 655 for (;;) { 656 error = cache_resolve(&nch, nd->nl_cred); 657 if (error != EAGAIN && 658 (nch.ncp->nc_flag & NCF_DESTROYED) == 0) { 659 break; 660 } 661 kprintf("[diagnostic] nlookup: relookup %*.*s\n", 662 nch.ncp->nc_nlen, nch.ncp->nc_nlen, 663 nch.ncp->nc_name); 664 cache_put(&nch); 665 nch = cache_nlookup(&nd->nl_nch, &nlc); 666 } 667 } 668 if (hvp) 669 vdrop(hvp); 670 wasdotordotdot = 0; 671 } 672 673 /* 674 * If the last component was "." or ".." our dflags no longer 675 * represents the parent directory and we have to explicitly 676 * look it up. 677 * 678 * Expect the parent to be good since nch is locked. 679 */ 680 if (wasdotordotdot && error == 0) { 681 dflags = 0; 682 if ((par.ncp = nch.ncp->nc_parent) != NULL) { 683 par.mount = nch.mount; 684 cache_hold(&par); 685 cache_lock_maybe_shared(&par, wantsexcllock(nd, ptr)); 686 error = naccess(&par, 0, nd->nl_cred, &dflags); 687 cache_put(&par); 688 } 689 } 690 691 /* 692 * [end of subsection] 693 * 694 * nch is locked and referenced. 695 * nd->nl_nch is unlocked and referenced. 696 * 697 * nl_nch must be unlocked or we could chain lock to the root 698 * if a resolve gets stuck (e.g. in NFS). 699 */ 700 KKASSERT((nd->nl_flags & NLC_NCPISLOCKED) == 0); 701 702 /* 703 * Resolve the namespace if necessary. The ncp returned by 704 * cache_nlookup() is referenced and locked. 705 * 706 * XXX neither '.' nor '..' should return EAGAIN since they were 707 * previously resolved and thus cannot be newly created ncp's. 708 */ 709 if (nch.ncp->nc_flag & NCF_UNRESOLVED) { 710 hit = 0; 711 error = cache_resolve(&nch, nd->nl_cred); 712 KKASSERT(error != EAGAIN); 713 } else { 714 error = nch.ncp->nc_error; 715 } 716 717 /* 718 * Early completion. ENOENT is not an error if this is the last 719 * component and NLC_CREATE or NLC_RENAME (rename target) was 720 * requested. Note that ncp->nc_error is left as ENOENT in that 721 * case, which we check later on. 722 * 723 * Also handle invalid '.' or '..' components terminating a path 724 * for a create/rename/delete. The standard requires this and pax 725 * pretty stupidly depends on it. 726 */ 727 if (islastelement(ptr)) { 728 if (error == ENOENT && 729 (nd->nl_flags & (NLC_CREATE | NLC_RENAME_DST)) 730 ) { 731 if (nd->nl_flags & NLC_NFS_RDONLY) { 732 error = EROFS; 733 } else { 734 error = naccess(&nch, nd->nl_flags | dflags, 735 nd->nl_cred, NULL); 736 } 737 } 738 if (error == 0 && wasdotordotdot && 739 (nd->nl_flags & (NLC_CREATE | NLC_DELETE | 740 NLC_RENAME_SRC | NLC_RENAME_DST))) { 741 /* 742 * POSIX junk 743 */ 744 if (nd->nl_flags & NLC_CREATE) 745 error = EEXIST; 746 else if (nd->nl_flags & NLC_DELETE) 747 error = (wasdotordotdot == 1) ? EINVAL : ENOTEMPTY; 748 else 749 error = EINVAL; 750 } 751 } 752 753 /* 754 * Early completion on error. 755 */ 756 if (error) { 757 cache_put(&nch); 758 break; 759 } 760 761 /* 762 * If the element is a symlink and it is either not the last 763 * element or it is the last element and we are allowed to 764 * follow symlinks, resolve the symlink. 765 */ 766 if ((nch.ncp->nc_flag & NCF_ISSYMLINK) && 767 (*ptr || (nd->nl_flags & NLC_FOLLOW)) 768 ) { 769 if (nd->nl_loopcnt++ >= MAXSYMLINKS) { 770 error = ELOOP; 771 cache_put(&nch); 772 break; 773 } 774 error = nreadsymlink(nd, &nch, &nlc); 775 cache_put(&nch); 776 if (error) 777 break; 778 779 /* 780 * Concatenate trailing path elements onto the returned symlink. 781 * Note that if the path component (ptr) is not exhausted, it 782 * will being with a '/', so we do not have to add another one. 783 * 784 * The symlink may not be empty. 785 */ 786 len = strlen(ptr); 787 if (nlc.nlc_namelen == 0 || nlc.nlc_namelen + len >= MAXPATHLEN) { 788 error = nlc.nlc_namelen ? ENAMETOOLONG : ENOENT; 789 objcache_put(namei_oc, nlc.nlc_nameptr); 790 break; 791 } 792 bcopy(ptr, nlc.nlc_nameptr + nlc.nlc_namelen, len + 1); 793 if (nd->nl_flags & NLC_HASBUF) 794 objcache_put(namei_oc, nd->nl_path); 795 nd->nl_path = nlc.nlc_nameptr; 796 nd->nl_flags |= NLC_HASBUF; 797 ptr = nd->nl_path; 798 799 /* 800 * Go back up to the top to resolve any initial '/'s in the 801 * symlink. 802 */ 803 continue; 804 } 805 806 /* 807 * If the element is a directory and we are crossing a mount point, 808 * Locate the mount. 809 */ 810 while ((nch.ncp->nc_flag & NCF_ISMOUNTPT) && 811 (nd->nl_flags & NLC_NOCROSSMOUNT) == 0 && 812 (mp = cache_findmount(&nch)) != NULL 813 ) { 814 struct vnode *tdp; 815 int vfs_do_busy = 0; 816 817 /* 818 * VFS must be busied before the namecache entry is locked, 819 * but we don't want to waste time calling vfs_busy() if the 820 * mount point is already resolved. 821 */ 822 again: 823 cache_put(&nch); 824 if (vfs_do_busy) { 825 while (vfs_busy(mp, 0)) { 826 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 827 kprintf("nlookup: warning umount race avoided\n"); 828 cache_dropmount(mp); 829 error = EBUSY; 830 vfs_do_busy = 0; 831 goto double_break; 832 } 833 } 834 } 835 cache_get_maybe_shared(&mp->mnt_ncmountpt, &nch, 836 wantsexcllock(nd, ptr)); 837 838 if (nch.ncp->nc_flag & NCF_UNRESOLVED) { 839 if (vfs_do_busy == 0) { 840 vfs_do_busy = 1; 841 goto again; 842 } 843 error = VFS_ROOT(mp, &tdp); 844 vfs_unbusy(mp); 845 vfs_do_busy = 0; 846 if (error) { 847 cache_dropmount(mp); 848 break; 849 } 850 cache_setvp(&nch, tdp); 851 vput(tdp); 852 } 853 if (vfs_do_busy) 854 vfs_unbusy(mp); 855 cache_dropmount(mp); 856 } 857 858 if (error) { 859 cache_put(&nch); 860 double_break: 861 break; 862 } 863 864 /* 865 * Skip any slashes to get to the next element. If there 866 * are any slashes at all the current element must be a 867 * directory or, in the create case, intended to become a directory. 868 * If it isn't we break without incrementing ptr and fall through 869 * to the failure case below. 870 */ 871 while (*ptr == '/') { 872 if ((nch.ncp->nc_flag & NCF_ISDIR) == 0 && 873 !(nd->nl_flags & NLC_WILLBEDIR) 874 ) { 875 break; 876 } 877 ++ptr; 878 } 879 880 /* 881 * Continuation case: additional elements and the current 882 * element is a directory. 883 */ 884 if (*ptr && (nch.ncp->nc_flag & NCF_ISDIR)) { 885 cache_drop(&nd->nl_nch); 886 cache_unlock(&nch); 887 KKASSERT((nd->nl_flags & NLC_NCPISLOCKED) == 0); 888 nd->nl_nch = nch; 889 continue; 890 } 891 892 /* 893 * Failure case: additional elements and the current element 894 * is not a directory 895 */ 896 if (*ptr) { 897 cache_put(&nch); 898 error = ENOTDIR; 899 break; 900 } 901 902 /* 903 * Successful lookup of last element. 904 * 905 * Check permissions if the target exists. If the target does not 906 * exist directory permissions were already tested in the early 907 * completion code above. 908 * 909 * nd->nl_flags will be adjusted on return with NLC_APPENDONLY 910 * if the file is marked append-only, and NLC_STICKY if the directory 911 * containing the file is sticky. 912 */ 913 if (nch.ncp->nc_vp && (nd->nl_flags & NLC_ALLCHKS)) { 914 error = naccess(&nch, nd->nl_flags | dflags, 915 nd->nl_cred, NULL); 916 if (error) { 917 cache_put(&nch); 918 break; 919 } 920 } 921 922 /* 923 * Termination: no more elements. 924 * 925 * If NLC_REFDVP is set acquire a referenced parent dvp. 926 */ 927 if (nd->nl_flags & NLC_REFDVP) { 928 cache_lock(&nd->nl_nch); 929 error = cache_vref(&nd->nl_nch, nd->nl_cred, &nd->nl_dvp); 930 cache_unlock(&nd->nl_nch); 931 if (error) { 932 kprintf("NLC_REFDVP: Cannot ref dvp of %p\n", nch.ncp); 933 cache_put(&nch); 934 break; 935 } 936 } 937 cache_drop(&nd->nl_nch); 938 nd->nl_nch = nch; 939 nd->nl_flags |= NLC_NCPISLOCKED; 940 error = 0; 941 break; 942 } 943 944 if (hit) 945 ++gd->gd_nchstats->ncs_longhits; 946 else 947 ++gd->gd_nchstats->ncs_longmiss; 948 949 if (nd->nl_flags & NLC_NCPISLOCKED) 950 KKASSERT(cache_lockstatus(&nd->nl_nch) > 0); 951 952 /* 953 * NOTE: If NLC_CREATE was set the ncp may represent a negative hit 954 * (ncp->nc_error will be ENOENT), but we will still return an error 955 * code of 0. 956 */ 957 return(error); 958 } 959 960 /* 961 * Resolve a mount point's glue ncp. This ncp connects creates the illusion 962 * of continuity in the namecache tree by connecting the ncp related to the 963 * vnode under the mount to the ncp related to the mount's root vnode. 964 * 965 * If no error occured a locked, ref'd ncp is stored in *ncpp. 966 */ 967 int 968 nlookup_mp(struct mount *mp, struct nchandle *nch) 969 { 970 struct vnode *vp; 971 int error; 972 973 error = 0; 974 cache_get(&mp->mnt_ncmountpt, nch); 975 if (nch->ncp->nc_flag & NCF_UNRESOLVED) { 976 while (vfs_busy(mp, 0)) 977 ; 978 error = VFS_ROOT(mp, &vp); 979 vfs_unbusy(mp); 980 if (error) { 981 cache_put(nch); 982 } else { 983 cache_setvp(nch, vp); 984 vput(vp); 985 } 986 } 987 return(error); 988 } 989 990 /* 991 * Read the contents of a symlink, allocate a path buffer out of the 992 * namei_oc and initialize the supplied nlcomponent with the result. 993 * 994 * If an error occurs no buffer will be allocated or returned in the nlc. 995 */ 996 int 997 nreadsymlink(struct nlookupdata *nd, struct nchandle *nch, 998 struct nlcomponent *nlc) 999 { 1000 struct vnode *vp; 1001 struct iovec aiov; 1002 struct uio auio; 1003 int linklen; 1004 int error; 1005 char *cp; 1006 1007 nlc->nlc_nameptr = NULL; 1008 nlc->nlc_namelen = 0; 1009 if (nch->ncp->nc_vp == NULL) 1010 return(ENOENT); 1011 if ((error = cache_vget(nch, nd->nl_cred, LK_SHARED, &vp)) != 0) 1012 return(error); 1013 cp = objcache_get(namei_oc, M_WAITOK); 1014 aiov.iov_base = cp; 1015 aiov.iov_len = MAXPATHLEN; 1016 auio.uio_iov = &aiov; 1017 auio.uio_iovcnt = 1; 1018 auio.uio_offset = 0; 1019 auio.uio_rw = UIO_READ; 1020 auio.uio_segflg = UIO_SYSSPACE; 1021 auio.uio_td = nd->nl_td; 1022 auio.uio_resid = MAXPATHLEN - 1; 1023 error = VOP_READLINK(vp, &auio, nd->nl_cred); 1024 if (error) 1025 goto fail; 1026 linklen = MAXPATHLEN - 1 - auio.uio_resid; 1027 if (varsym_enable) { 1028 linklen = varsymreplace(cp, linklen, MAXPATHLEN - 1); 1029 if (linklen < 0) { 1030 error = ENAMETOOLONG; 1031 goto fail; 1032 } 1033 } 1034 cp[linklen] = 0; 1035 nlc->nlc_nameptr = cp; 1036 nlc->nlc_namelen = linklen; 1037 vput(vp); 1038 return(0); 1039 fail: 1040 objcache_put(namei_oc, cp); 1041 vput(vp); 1042 return(error); 1043 } 1044 1045 /* 1046 * Check access [XXX cache vattr!] [XXX quota] 1047 * 1048 * Generally check the NLC_* access bits. All specified bits must pass 1049 * for this function to return 0. 1050 * 1051 * The file does not have to exist when checking NLC_CREATE or NLC_RENAME_DST 1052 * access, otherwise it must exist. No error is returned in this case. 1053 * 1054 * The file must not exist if NLC_EXCL is specified. 1055 * 1056 * Directory permissions in general are tested for NLC_CREATE if the file 1057 * does not exist, NLC_DELETE if the file does exist, and NLC_RENAME_DST 1058 * whether the file exists or not. 1059 * 1060 * The directory sticky bit is tested for NLC_DELETE and NLC_RENAME_DST, 1061 * the latter is only tested if the target exists. 1062 * 1063 * The passed ncp must be referenced and locked. If it is already resolved 1064 * it may be locked shared but otherwise should be locked exclusively. 1065 */ 1066 static int 1067 naccess(struct nchandle *nch, int nflags, struct ucred *cred, int *nflagsp) 1068 { 1069 struct vnode *vp; 1070 struct vattr va; 1071 struct namecache *ncp; 1072 int error; 1073 int cflags; 1074 1075 KKASSERT(cache_lockstatus(nch) > 0); 1076 1077 ncp = nch->ncp; 1078 if (ncp->nc_flag & NCF_UNRESOLVED) { 1079 cache_resolve(nch, cred); 1080 ncp = nch->ncp; 1081 } 1082 error = ncp->nc_error; 1083 1084 /* 1085 * Directory permissions checks. Silently ignore ENOENT if these 1086 * tests pass. It isn't an error. 1087 * 1088 * We can safely resolve ncp->nc_parent because ncp is currently 1089 * locked. 1090 */ 1091 if (nflags & (NLC_CREATE | NLC_DELETE | NLC_RENAME_SRC | NLC_RENAME_DST)) { 1092 if (((nflags & NLC_CREATE) && ncp->nc_vp == NULL) || 1093 ((nflags & NLC_DELETE) && ncp->nc_vp != NULL) || 1094 ((nflags & NLC_RENAME_SRC) && ncp->nc_vp != NULL) || 1095 (nflags & NLC_RENAME_DST) 1096 ) { 1097 struct nchandle par; 1098 1099 if ((par.ncp = ncp->nc_parent) == NULL) { 1100 if (error != EAGAIN) 1101 error = EINVAL; 1102 } else if (error == 0 || error == ENOENT) { 1103 par.mount = nch->mount; 1104 cache_hold(&par); 1105 cache_lock_maybe_shared(&par, 0); 1106 error = naccess(&par, NLC_WRITE, cred, NULL); 1107 cache_put(&par); 1108 } 1109 } 1110 } 1111 1112 /* 1113 * NLC_EXCL check. Target file must not exist. 1114 */ 1115 if (error == 0 && (nflags & NLC_EXCL) && ncp->nc_vp != NULL) 1116 error = EEXIST; 1117 1118 /* 1119 * Get the vnode attributes so we can do the rest of our checks. 1120 * 1121 * NOTE: We only call naccess_va() if the target exists. 1122 */ 1123 if (error == 0) { 1124 error = cache_vget(nch, cred, LK_SHARED, &vp); 1125 if (error == ENOENT) { 1126 /* 1127 * Silently zero-out ENOENT if creating or renaming 1128 * (rename target). It isn't an error. 1129 */ 1130 if (nflags & (NLC_CREATE | NLC_RENAME_DST)) 1131 error = 0; 1132 } else if (error == 0) { 1133 /* 1134 * Get the vnode attributes and check for illegal O_TRUNC 1135 * requests and read-only mounts. 1136 * 1137 * NOTE: You can still open devices on read-only mounts for 1138 * writing. 1139 * 1140 * NOTE: creates/deletes/renames are handled by the NLC_WRITE 1141 * check on the parent directory above. 1142 * 1143 * XXX cache the va in the namecache or in the vnode 1144 */ 1145 error = VOP_GETATTR(vp, &va); 1146 if (error == 0 && (nflags & NLC_TRUNCATE)) { 1147 switch(va.va_type) { 1148 case VREG: 1149 case VDATABASE: 1150 case VCHR: 1151 case VBLK: 1152 case VFIFO: 1153 break; 1154 case VDIR: 1155 error = EISDIR; 1156 break; 1157 default: 1158 error = EINVAL; 1159 break; 1160 } 1161 } 1162 if (error == 0 && (nflags & NLC_WRITE) && vp->v_mount && 1163 (vp->v_mount->mnt_flag & MNT_RDONLY) 1164 ) { 1165 switch(va.va_type) { 1166 case VDIR: 1167 case VLNK: 1168 case VREG: 1169 case VDATABASE: 1170 error = EROFS; 1171 break; 1172 default: 1173 break; 1174 } 1175 } 1176 vput(vp); 1177 1178 /* 1179 * Check permissions based on file attributes. The passed 1180 * flags (*nflagsp) are modified with feedback based on 1181 * special attributes and requirements. 1182 */ 1183 if (error == 0) { 1184 /* 1185 * Adjust the returned (*nflagsp) if non-NULL. 1186 */ 1187 if (nflagsp) { 1188 if ((va.va_mode & VSVTX) && va.va_uid != cred->cr_uid) 1189 *nflagsp |= NLC_STICKY; 1190 if (va.va_flags & APPEND) 1191 *nflagsp |= NLC_APPENDONLY; 1192 if (va.va_flags & IMMUTABLE) 1193 *nflagsp |= NLC_IMMUTABLE; 1194 } 1195 1196 /* 1197 * Track swapcache management flags in the namecache. 1198 * 1199 * Calculate the flags based on the current vattr info 1200 * and recalculate the inherited flags from the parent 1201 * (the original cache linkage may have occurred without 1202 * getattrs and thus have stale flags). 1203 */ 1204 cflags = 0; 1205 if (va.va_flags & SF_NOCACHE) 1206 cflags |= NCF_SF_NOCACHE; 1207 if (va.va_flags & UF_CACHE) 1208 cflags |= NCF_UF_CACHE; 1209 if (ncp->nc_parent) { 1210 if (ncp->nc_parent->nc_flag & 1211 (NCF_SF_NOCACHE | NCF_SF_PNOCACHE)) { 1212 cflags |= NCF_SF_PNOCACHE; 1213 } 1214 if (ncp->nc_parent->nc_flag & 1215 (NCF_UF_CACHE | NCF_UF_PCACHE)) { 1216 cflags |= NCF_UF_PCACHE; 1217 } 1218 } 1219 1220 /* 1221 * XXX we're not supposed to update nc_flag when holding 1222 * a shared lock. 1223 */ 1224 atomic_clear_short(&ncp->nc_flag, 1225 (NCF_SF_NOCACHE | NCF_UF_CACHE | 1226 NCF_SF_PNOCACHE | NCF_UF_PCACHE) & ~cflags); 1227 atomic_set_short(&ncp->nc_flag, cflags); 1228 1229 /* 1230 * Process general access. 1231 */ 1232 error = naccess_va(&va, nflags, cred); 1233 } 1234 } 1235 } 1236 return(error); 1237 } 1238 1239 /* 1240 * Check the requested access against the given vattr using cred. 1241 */ 1242 int 1243 naccess_va(struct vattr *va, int nflags, struct ucred *cred) 1244 { 1245 int i; 1246 int vmode; 1247 1248 /* 1249 * Test the immutable bit. Creations, deletions, renames (source 1250 * or destination) are not allowed. chown/chmod/other is also not 1251 * allowed but is handled by SETATTR. Hardlinks to the immutable 1252 * file are allowed. 1253 * 1254 * If the directory is set to immutable then creations, deletions, 1255 * renames (source or dest) and hardlinks to files within the directory 1256 * are not allowed, and regular files opened through the directory may 1257 * not be written to or truncated (unless a special device). 1258 * 1259 * NOTE! New hardlinks to immutable files work but new hardlinks to 1260 * files, immutable or not, sitting inside an immutable directory are 1261 * not allowed. As always if the file is hardlinked via some other 1262 * path additional hardlinks may be possible even if the file is marked 1263 * immutable. The sysop needs to create a closure by checking the hard 1264 * link count. Once closure is achieved you are good, and security 1265 * scripts should check link counts anyway. 1266 * 1267 * Writes and truncations are only allowed on special devices. 1268 */ 1269 if ((va->va_flags & IMMUTABLE) || (nflags & NLC_IMMUTABLE)) { 1270 if ((nflags & NLC_IMMUTABLE) && (nflags & NLC_HLINK)) 1271 return (EPERM); 1272 if (nflags & (NLC_CREATE | NLC_DELETE | 1273 NLC_RENAME_SRC | NLC_RENAME_DST)) { 1274 return (EPERM); 1275 } 1276 if (nflags & (NLC_WRITE | NLC_TRUNCATE)) { 1277 switch(va->va_type) { 1278 case VDIR: 1279 return (EISDIR); 1280 case VLNK: 1281 case VREG: 1282 case VDATABASE: 1283 return (EPERM); 1284 default: 1285 break; 1286 } 1287 } 1288 } 1289 1290 /* 1291 * Test the no-unlink and append-only bits for opens, rename targets, 1292 * and deletions. These bits are not tested for creations or 1293 * rename sources. 1294 * 1295 * Unlike FreeBSD we allow a file with APPEND set to be renamed. 1296 * If you do not wish this you must also set NOUNLINK. 1297 * 1298 * If the governing directory is marked APPEND-only it implies 1299 * NOUNLINK for all entries in the directory. 1300 */ 1301 if (((va->va_flags & NOUNLINK) || (nflags & NLC_APPENDONLY)) && 1302 (nflags & (NLC_DELETE | NLC_RENAME_SRC | NLC_RENAME_DST)) 1303 ) { 1304 return (EPERM); 1305 } 1306 1307 /* 1308 * A file marked append-only may not be deleted but can be renamed. 1309 */ 1310 if ((va->va_flags & APPEND) && 1311 (nflags & (NLC_DELETE | NLC_RENAME_DST)) 1312 ) { 1313 return (EPERM); 1314 } 1315 1316 /* 1317 * A file marked append-only which is opened for writing must also 1318 * be opened O_APPEND. 1319 */ 1320 if ((va->va_flags & APPEND) && (nflags & (NLC_OPEN | NLC_TRUNCATE))) { 1321 if (nflags & NLC_TRUNCATE) 1322 return (EPERM); 1323 if ((nflags & (NLC_OPEN | NLC_WRITE)) == (NLC_OPEN | NLC_WRITE)) { 1324 if ((nflags & NLC_APPEND) == 0) 1325 return (EPERM); 1326 } 1327 } 1328 1329 /* 1330 * root gets universal access 1331 */ 1332 if (cred->cr_uid == 0) 1333 return(0); 1334 1335 /* 1336 * Check owner perms. 1337 * 1338 * If NLC_OWN is set the owner of the file is allowed no matter when 1339 * the owner-mode bits say (utimes). 1340 */ 1341 vmode = 0; 1342 if (nflags & NLC_READ) 1343 vmode |= S_IRUSR; 1344 if (nflags & NLC_WRITE) 1345 vmode |= S_IWUSR; 1346 if (nflags & NLC_EXEC) 1347 vmode |= S_IXUSR; 1348 1349 if (cred->cr_uid == va->va_uid) { 1350 if ((nflags & NLC_OWN) == 0) { 1351 if ((vmode & va->va_mode) != vmode) 1352 return(EACCES); 1353 } 1354 return(0); 1355 } 1356 1357 /* 1358 * If NLC_STICKY is set only the owner may delete or rename a file. 1359 * This bit is typically set on /tmp. 1360 * 1361 * Note that the NLC_READ/WRITE/EXEC bits are not typically set in 1362 * the specific delete or rename case. For deletions and renames we 1363 * usually just care about directory permissions, not file permissions. 1364 */ 1365 if ((nflags & NLC_STICKY) && 1366 (nflags & (NLC_RENAME_SRC | NLC_RENAME_DST | NLC_DELETE))) { 1367 return(EACCES); 1368 } 1369 1370 /* 1371 * Check group perms 1372 */ 1373 vmode >>= 3; 1374 for (i = 0; i < cred->cr_ngroups; ++i) { 1375 if (va->va_gid == cred->cr_groups[i]) { 1376 if ((vmode & va->va_mode) != vmode) 1377 return(EACCES); 1378 return(0); 1379 } 1380 } 1381 1382 /* 1383 * Check world perms 1384 */ 1385 vmode >>= 3; 1386 if ((vmode & va->va_mode) != vmode) 1387 return(EACCES); 1388 return(0); 1389 } 1390 1391