1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1999-2002 Robert N. M. Watson 5 * Copyright (c) 2002-2003 Networks Associates Technology, Inc. 6 * All rights reserved. 7 * 8 * This software was developed by Robert Watson for the TrustedBSD Project. 9 * 10 * This software was developed for the FreeBSD Project in part by Network 11 * Associates Laboratories, the Security Research Division of Network 12 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), 13 * as part of the DARPA CHATS research program. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 */ 37 38 /* 39 * Support for filesystem extended attribute: UFS-specific support functions. 40 */ 41 42 #include <sys/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include "opt_ufs.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/ktr.h> 51 #include <sys/namei.h> 52 #include <sys/malloc.h> 53 #include <sys/fcntl.h> 54 #include <sys/priv.h> 55 #include <sys/proc.h> 56 #include <sys/vnode.h> 57 #include <sys/mount.h> 58 #include <sys/lock.h> 59 #include <sys/dirent.h> 60 #include <sys/extattr.h> 61 #include <sys/sx.h> 62 #include <sys/sysctl.h> 63 64 #include <vm/uma.h> 65 66 #include <ufs/ufs/dir.h> 67 #include <ufs/ufs/extattr.h> 68 #include <ufs/ufs/quota.h> 69 #include <ufs/ufs/ufsmount.h> 70 #include <ufs/ufs/inode.h> 71 #include <ufs/ufs/ufs_extern.h> 72 73 #ifdef UFS_EXTATTR 74 75 FEATURE(ufs_extattr, "ufs extended attribute support"); 76 77 static MALLOC_DEFINE(M_UFS_EXTATTR, "ufs_extattr", "ufs extended attribute"); 78 79 static int ufs_extattr_sync = 0; 80 SYSCTL_INT(_debug, OID_AUTO, ufs_extattr_sync, CTLFLAG_RW, &ufs_extattr_sync, 81 0, ""); 82 83 static int ufs_extattr_valid_attrname(int attrnamespace, 84 const char *attrname); 85 static int ufs_extattr_enable_with_open(struct ufsmount *ump, 86 struct vnode *vp, int attrnamespace, const char *attrname, 87 struct thread *td); 88 static int ufs_extattr_enable(struct ufsmount *ump, int attrnamespace, 89 const char *attrname, struct vnode *backing_vnode, 90 struct thread *td); 91 static int ufs_extattr_disable(struct ufsmount *ump, int attrnamespace, 92 const char *attrname, struct thread *td); 93 static int ufs_extattr_get(struct vnode *vp, int attrnamespace, 94 const char *name, struct uio *uio, size_t *size, 95 struct ucred *cred, struct thread *td); 96 static int ufs_extattr_set(struct vnode *vp, int attrnamespace, 97 const char *name, struct uio *uio, struct ucred *cred, 98 struct thread *td); 99 static int ufs_extattr_rm(struct vnode *vp, int attrnamespace, 100 const char *name, struct ucred *cred, struct thread *td); 101 #ifdef UFS_EXTATTR_AUTOSTART 102 static int ufs_extattr_autostart_locked(struct mount *mp, 103 struct thread *td); 104 #endif 105 static int ufs_extattr_start_locked(struct ufsmount *ump, 106 struct thread *td); 107 108 /* 109 * Per-FS attribute lock protecting attribute operations. 110 * 111 * XXXRW: Perhaps something more fine-grained would be appropriate, but at 112 * the end of the day we're going to contend on the vnode lock for the 113 * backing file anyway. 114 */ 115 static void 116 ufs_extattr_uepm_lock(struct ufsmount *ump) 117 { 118 119 sx_xlock(&ump->um_extattr.uepm_lock); 120 } 121 122 static void 123 ufs_extattr_uepm_unlock(struct ufsmount *ump) 124 { 125 126 sx_xunlock(&ump->um_extattr.uepm_lock); 127 } 128 129 /*- 130 * Determine whether the name passed is a valid name for an actual 131 * attribute. 132 * 133 * Invalid currently consists of: 134 * NULL pointer for attrname 135 * zero-length attrname (used to retrieve application attribute list) 136 */ 137 static int 138 ufs_extattr_valid_attrname(int attrnamespace, const char *attrname) 139 { 140 141 if (attrname == NULL) 142 return (0); 143 if (strlen(attrname) == 0) 144 return (0); 145 return (1); 146 } 147 148 /* 149 * Locate an attribute given a name and mountpoint. 150 * Must be holding uepm lock for the mount point. 151 */ 152 static struct ufs_extattr_list_entry * 153 ufs_extattr_find_attr(struct ufsmount *ump, int attrnamespace, 154 const char *attrname) 155 { 156 struct ufs_extattr_list_entry *search_attribute; 157 158 sx_assert(&ump->um_extattr.uepm_lock, SA_XLOCKED); 159 160 for (search_attribute = LIST_FIRST(&ump->um_extattr.uepm_list); 161 search_attribute != NULL; 162 search_attribute = LIST_NEXT(search_attribute, uele_entries)) { 163 if (!(strncmp(attrname, search_attribute->uele_attrname, 164 UFS_EXTATTR_MAXEXTATTRNAME)) && 165 (attrnamespace == search_attribute->uele_attrnamespace)) { 166 return (search_attribute); 167 } 168 } 169 170 return (0); 171 } 172 173 /* 174 * Initialize per-FS structures supporting extended attributes. Do not 175 * start extended attributes yet. 176 */ 177 void 178 ufs_extattr_uepm_init(struct ufs_extattr_per_mount *uepm) 179 { 180 181 uepm->uepm_flags = 0; 182 LIST_INIT(&uepm->uepm_list); 183 sx_init(&uepm->uepm_lock, "ufs_extattr_sx"); 184 uepm->uepm_flags |= UFS_EXTATTR_UEPM_INITIALIZED; 185 } 186 187 /* 188 * Destroy per-FS structures supporting extended attributes. Assumes 189 * that EAs have already been stopped, and will panic if not. 190 */ 191 void 192 ufs_extattr_uepm_destroy(struct ufs_extattr_per_mount *uepm) 193 { 194 195 if (!(uepm->uepm_flags & UFS_EXTATTR_UEPM_INITIALIZED)) 196 panic("ufs_extattr_uepm_destroy: not initialized"); 197 198 if ((uepm->uepm_flags & UFS_EXTATTR_UEPM_STARTED)) 199 panic("ufs_extattr_uepm_destroy: called while still started"); 200 201 /* 202 * It's not clear that either order for the next two lines is 203 * ideal, and it should never be a problem if this is only called 204 * during unmount, and with vfs_busy(). 205 */ 206 uepm->uepm_flags &= ~UFS_EXTATTR_UEPM_INITIALIZED; 207 sx_destroy(&uepm->uepm_lock); 208 } 209 210 /* 211 * Start extended attribute support on an FS. 212 */ 213 int 214 ufs_extattr_start(struct mount *mp, struct thread *td) 215 { 216 struct ufsmount *ump; 217 int error = 0; 218 219 ump = VFSTOUFS(mp); 220 221 ufs_extattr_uepm_lock(ump); 222 error = ufs_extattr_start_locked(ump, td); 223 ufs_extattr_uepm_unlock(ump); 224 return (error); 225 } 226 227 static int 228 ufs_extattr_start_locked(struct ufsmount *ump, struct thread *td) 229 { 230 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_INITIALIZED)) 231 return (EOPNOTSUPP); 232 if (ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED) 233 return (EBUSY); 234 235 ump->um_extattr.uepm_flags |= UFS_EXTATTR_UEPM_STARTED; 236 ump->um_extattr.uepm_ucred = crhold(td->td_ucred); 237 return (0); 238 } 239 240 #ifdef UFS_EXTATTR_AUTOSTART 241 /* 242 * Helper routine: given a locked parent directory and filename, return 243 * the locked vnode of the inode associated with the name. Will not 244 * follow symlinks, may return any type of vnode. Lock on parent will 245 * be released even in the event of a failure. In the event that the 246 * target is the parent (i.e., "."), there will be two references and 247 * one lock, requiring the caller to possibly special-case. 248 */ 249 #define UE_GETDIR_LOCKPARENT 1 250 #define UE_GETDIR_LOCKPARENT_DONT 2 251 static int 252 ufs_extattr_lookup(struct vnode *start_dvp, int lockparent, char *dirname, 253 struct vnode **vp, struct thread *td) 254 { 255 struct vop_cachedlookup_args vargs; 256 struct componentname cnp; 257 struct vnode *target_vp; 258 int error; 259 260 bzero(&cnp, sizeof(cnp)); 261 cnp.cn_nameiop = LOOKUP; 262 cnp.cn_flags = ISLASTCN; 263 if (lockparent == UE_GETDIR_LOCKPARENT) 264 cnp.cn_flags |= LOCKPARENT; 265 cnp.cn_lkflags = LK_EXCLUSIVE; 266 cnp.cn_cred = td->td_ucred; 267 cnp.cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK); 268 cnp.cn_nameptr = cnp.cn_pnbuf; 269 error = copystr(dirname, cnp.cn_pnbuf, MAXPATHLEN, 270 (size_t *) &cnp.cn_namelen); 271 if (error) { 272 if (lockparent == UE_GETDIR_LOCKPARENT_DONT) { 273 VOP_UNLOCK(start_dvp); 274 } 275 uma_zfree(namei_zone, cnp.cn_pnbuf); 276 printf("ufs_extattr_lookup: copystr failed\n"); 277 return (error); 278 } 279 cnp.cn_namelen--; /* trim nul termination */ 280 vargs.a_gen.a_desc = NULL; 281 vargs.a_dvp = start_dvp; 282 vargs.a_vpp = &target_vp; 283 vargs.a_cnp = &cnp; 284 error = ufs_lookup(&vargs); 285 uma_zfree(namei_zone, cnp.cn_pnbuf); 286 if (error) { 287 /* 288 * Error condition, may have to release the lock on the parent 289 * if ufs_lookup() didn't. 290 */ 291 if (lockparent == UE_GETDIR_LOCKPARENT_DONT) 292 VOP_UNLOCK(start_dvp); 293 294 /* 295 * Check that ufs_lookup() didn't release the lock when we 296 * didn't want it to. 297 */ 298 if (lockparent == UE_GETDIR_LOCKPARENT) 299 ASSERT_VOP_LOCKED(start_dvp, "ufs_extattr_lookup"); 300 301 return (error); 302 } 303 /* 304 if (target_vp == start_dvp) 305 panic("ufs_extattr_lookup: target_vp == start_dvp"); 306 */ 307 308 if (target_vp != start_dvp && lockparent == UE_GETDIR_LOCKPARENT_DONT) 309 VOP_UNLOCK(start_dvp); 310 311 if (lockparent == UE_GETDIR_LOCKPARENT) 312 ASSERT_VOP_LOCKED(start_dvp, "ufs_extattr_lookup"); 313 314 /* printf("ufs_extattr_lookup: success\n"); */ 315 *vp = target_vp; 316 return (0); 317 } 318 #endif /* !UFS_EXTATTR_AUTOSTART */ 319 320 /* 321 * Enable an EA using the passed filesystem, backing vnode, attribute name, 322 * namespace, and proc. Will perform a VOP_OPEN() on the vp, so expects vp 323 * to be locked when passed in. The vnode will be returned unlocked, 324 * regardless of success/failure of the function. As a result, the caller 325 * will always need to vrele(), but not vput(). 326 */ 327 static int 328 ufs_extattr_enable_with_open(struct ufsmount *ump, struct vnode *vp, 329 int attrnamespace, const char *attrname, struct thread *td) 330 { 331 int error; 332 333 error = VOP_OPEN(vp, FREAD|FWRITE, td->td_ucred, td, NULL); 334 if (error) { 335 printf("ufs_extattr_enable_with_open.VOP_OPEN(): failed " 336 "with %d\n", error); 337 VOP_UNLOCK(vp); 338 return (error); 339 } 340 341 error = VOP_ADD_WRITECOUNT(vp, 1); 342 if (error != 0) { 343 VOP_CLOSE(vp, FREAD | FWRITE, td->td_ucred, td); 344 VOP_UNLOCK(vp); 345 return (error); 346 } 347 CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d", __func__, vp, 348 vp->v_writecount); 349 350 vref(vp); 351 352 VOP_UNLOCK(vp); 353 354 error = ufs_extattr_enable(ump, attrnamespace, attrname, vp, td); 355 if (error != 0) 356 vn_close(vp, FREAD|FWRITE, td->td_ucred, td); 357 return (error); 358 } 359 360 #ifdef UFS_EXTATTR_AUTOSTART 361 /* 362 * Given a locked directory vnode, iterate over the names in the directory 363 * and use ufs_extattr_lookup() to retrieve locked vnodes of potential 364 * attribute files. Then invoke ufs_extattr_enable_with_open() on each 365 * to attempt to start the attribute. Leaves the directory locked on 366 * exit. 367 */ 368 static int 369 ufs_extattr_iterate_directory(struct ufsmount *ump, struct vnode *dvp, 370 int attrnamespace, struct thread *td) 371 { 372 struct vop_readdir_args vargs; 373 struct dirent *dp, *edp; 374 struct vnode *attr_vp; 375 struct uio auio; 376 struct iovec aiov; 377 char *dirbuf; 378 int error, eofflag = 0; 379 380 if (dvp->v_type != VDIR) 381 return (ENOTDIR); 382 383 dirbuf = malloc(DIRBLKSIZ, M_TEMP, M_WAITOK); 384 385 auio.uio_iov = &aiov; 386 auio.uio_iovcnt = 1; 387 auio.uio_rw = UIO_READ; 388 auio.uio_segflg = UIO_SYSSPACE; 389 auio.uio_td = td; 390 auio.uio_offset = 0; 391 392 vargs.a_gen.a_desc = NULL; 393 vargs.a_vp = dvp; 394 vargs.a_uio = &auio; 395 vargs.a_cred = td->td_ucred; 396 vargs.a_eofflag = &eofflag; 397 vargs.a_ncookies = NULL; 398 vargs.a_cookies = NULL; 399 400 while (!eofflag) { 401 auio.uio_resid = DIRBLKSIZ; 402 aiov.iov_base = dirbuf; 403 aiov.iov_len = DIRBLKSIZ; 404 error = ufs_readdir(&vargs); 405 if (error) { 406 printf("ufs_extattr_iterate_directory: ufs_readdir " 407 "%d\n", error); 408 return (error); 409 } 410 411 edp = (struct dirent *)&dirbuf[DIRBLKSIZ - auio.uio_resid]; 412 for (dp = (struct dirent *)dirbuf; dp < edp; ) { 413 if (dp->d_reclen == 0) 414 break; 415 error = ufs_extattr_lookup(dvp, UE_GETDIR_LOCKPARENT, 416 dp->d_name, &attr_vp, td); 417 if (error) { 418 printf("ufs_extattr_iterate_directory: lookup " 419 "%s %d\n", dp->d_name, error); 420 } else if (attr_vp == dvp) { 421 vrele(attr_vp); 422 } else if (attr_vp->v_type != VREG) { 423 vput(attr_vp); 424 } else { 425 error = ufs_extattr_enable_with_open(ump, 426 attr_vp, attrnamespace, dp->d_name, td); 427 vrele(attr_vp); 428 if (error) { 429 printf("ufs_extattr_iterate_directory: " 430 "enable %s %d\n", dp->d_name, 431 error); 432 } else if (bootverbose) { 433 printf("UFS autostarted EA %s\n", 434 dp->d_name); 435 } 436 } 437 dp = (struct dirent *) ((char *)dp + dp->d_reclen); 438 if (dp >= edp) 439 break; 440 } 441 } 442 free(dirbuf, M_TEMP); 443 444 return (0); 445 } 446 447 /* 448 * Auto-start of extended attributes, to be executed (optionally) at 449 * mount-time. 450 */ 451 int 452 ufs_extattr_autostart(struct mount *mp, struct thread *td) 453 { 454 struct ufsmount *ump; 455 int error; 456 457 ump = VFSTOUFS(mp); 458 ufs_extattr_uepm_lock(ump); 459 error = ufs_extattr_autostart_locked(mp, td); 460 ufs_extattr_uepm_unlock(ump); 461 return (error); 462 } 463 464 static int 465 ufs_extattr_autostart_locked(struct mount *mp, struct thread *td) 466 { 467 struct vnode *rvp, *attr_dvp, *attr_system_dvp, *attr_user_dvp; 468 struct ufsmount *ump = VFSTOUFS(mp); 469 int error; 470 471 /* 472 * UFS_EXTATTR applies only to UFS1, as UFS2 uses native extended 473 * attributes, so don't autostart. 474 */ 475 if (ump->um_fstype != UFS1) 476 return (0); 477 478 /* 479 * Does UFS_EXTATTR_FSROOTSUBDIR exist off the filesystem root? 480 * If so, automatically start EA's. 481 */ 482 error = VFS_ROOT(mp, LK_EXCLUSIVE, &rvp); 483 if (error) { 484 printf("ufs_extattr_autostart.VFS_ROOT() returned %d\n", 485 error); 486 return (error); 487 } 488 489 error = ufs_extattr_lookup(rvp, UE_GETDIR_LOCKPARENT_DONT, 490 UFS_EXTATTR_FSROOTSUBDIR, &attr_dvp, td); 491 if (error) { 492 /* rvp ref'd but now unlocked */ 493 vrele(rvp); 494 return (error); 495 } 496 if (rvp == attr_dvp) { 497 /* Should never happen. */ 498 vput(rvp); 499 vrele(attr_dvp); 500 return (EINVAL); 501 } 502 vrele(rvp); 503 504 if (attr_dvp->v_type != VDIR) { 505 printf("ufs_extattr_autostart: %s != VDIR\n", 506 UFS_EXTATTR_FSROOTSUBDIR); 507 goto return_vput_attr_dvp; 508 } 509 510 error = ufs_extattr_start_locked(ump, td); 511 if (error) { 512 printf("ufs_extattr_autostart: ufs_extattr_start failed (%d)\n", 513 error); 514 goto return_vput_attr_dvp; 515 } 516 517 /* 518 * Look for two subdirectories: UFS_EXTATTR_SUBDIR_SYSTEM, 519 * UFS_EXTATTR_SUBDIR_USER. For each, iterate over the sub-directory, 520 * and start with appropriate type. Failures in either don't 521 * result in an over-all failure. attr_dvp is left locked to 522 * be cleaned up on exit. 523 */ 524 error = ufs_extattr_lookup(attr_dvp, UE_GETDIR_LOCKPARENT, 525 UFS_EXTATTR_SUBDIR_SYSTEM, &attr_system_dvp, td); 526 if (!error) { 527 error = ufs_extattr_iterate_directory(VFSTOUFS(mp), 528 attr_system_dvp, EXTATTR_NAMESPACE_SYSTEM, td); 529 if (error) 530 printf("ufs_extattr_iterate_directory returned %d\n", 531 error); 532 vput(attr_system_dvp); 533 } 534 535 error = ufs_extattr_lookup(attr_dvp, UE_GETDIR_LOCKPARENT, 536 UFS_EXTATTR_SUBDIR_USER, &attr_user_dvp, td); 537 if (!error) { 538 error = ufs_extattr_iterate_directory(VFSTOUFS(mp), 539 attr_user_dvp, EXTATTR_NAMESPACE_USER, td); 540 if (error) 541 printf("ufs_extattr_iterate_directory returned %d\n", 542 error); 543 vput(attr_user_dvp); 544 } 545 546 /* Mask startup failures in sub-directories. */ 547 error = 0; 548 549 return_vput_attr_dvp: 550 vput(attr_dvp); 551 552 return (error); 553 } 554 #endif /* !UFS_EXTATTR_AUTOSTART */ 555 556 /* 557 * Stop extended attribute support on an FS. 558 */ 559 int 560 ufs_extattr_stop(struct mount *mp, struct thread *td) 561 { 562 struct ufs_extattr_list_entry *uele; 563 struct ufsmount *ump = VFSTOUFS(mp); 564 int error = 0; 565 566 ufs_extattr_uepm_lock(ump); 567 568 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED)) { 569 error = EOPNOTSUPP; 570 goto unlock; 571 } 572 573 while ((uele = LIST_FIRST(&ump->um_extattr.uepm_list)) != NULL) { 574 ufs_extattr_disable(ump, uele->uele_attrnamespace, 575 uele->uele_attrname, td); 576 } 577 578 ump->um_extattr.uepm_flags &= ~UFS_EXTATTR_UEPM_STARTED; 579 580 crfree(ump->um_extattr.uepm_ucred); 581 ump->um_extattr.uepm_ucred = NULL; 582 583 unlock: 584 ufs_extattr_uepm_unlock(ump); 585 586 return (error); 587 } 588 589 /* 590 * Enable a named attribute on the specified filesystem; provide an 591 * unlocked backing vnode to hold the attribute data. 592 */ 593 static int 594 ufs_extattr_enable(struct ufsmount *ump, int attrnamespace, 595 const char *attrname, struct vnode *backing_vnode, struct thread *td) 596 { 597 struct ufs_extattr_list_entry *attribute; 598 struct iovec aiov; 599 struct uio auio; 600 int error = 0; 601 602 if (!ufs_extattr_valid_attrname(attrnamespace, attrname)) 603 return (EINVAL); 604 if (backing_vnode->v_type != VREG) 605 return (EINVAL); 606 607 attribute = malloc(sizeof(struct ufs_extattr_list_entry), 608 M_UFS_EXTATTR, M_WAITOK); 609 610 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED)) { 611 error = EOPNOTSUPP; 612 goto free_exit; 613 } 614 615 if (ufs_extattr_find_attr(ump, attrnamespace, attrname)) { 616 error = EEXIST; 617 goto free_exit; 618 } 619 620 strncpy(attribute->uele_attrname, attrname, 621 UFS_EXTATTR_MAXEXTATTRNAME); 622 attribute->uele_attrnamespace = attrnamespace; 623 bzero(&attribute->uele_fileheader, 624 sizeof(struct ufs_extattr_fileheader)); 625 626 attribute->uele_backing_vnode = backing_vnode; 627 628 auio.uio_iov = &aiov; 629 auio.uio_iovcnt = 1; 630 aiov.iov_base = (caddr_t) &attribute->uele_fileheader; 631 aiov.iov_len = sizeof(struct ufs_extattr_fileheader); 632 auio.uio_resid = sizeof(struct ufs_extattr_fileheader); 633 auio.uio_offset = (off_t) 0; 634 auio.uio_segflg = UIO_SYSSPACE; 635 auio.uio_rw = UIO_READ; 636 auio.uio_td = td; 637 638 vn_lock(backing_vnode, LK_SHARED | LK_RETRY); 639 error = VOP_READ(backing_vnode, &auio, IO_NODELOCKED, 640 ump->um_extattr.uepm_ucred); 641 642 if (error) 643 goto unlock_free_exit; 644 645 if (auio.uio_resid != 0) { 646 printf("ufs_extattr_enable: malformed attribute header\n"); 647 error = EINVAL; 648 goto unlock_free_exit; 649 } 650 651 if (attribute->uele_fileheader.uef_magic != UFS_EXTATTR_MAGIC) { 652 printf("ufs_extattr_enable: invalid attribute header magic\n"); 653 error = EINVAL; 654 goto unlock_free_exit; 655 } 656 657 if (attribute->uele_fileheader.uef_version != UFS_EXTATTR_VERSION) { 658 printf("ufs_extattr_enable: incorrect attribute header " 659 "version\n"); 660 error = EINVAL; 661 goto unlock_free_exit; 662 } 663 664 ASSERT_VOP_LOCKED(backing_vnode, "ufs_extattr_enable"); 665 LIST_INSERT_HEAD(&ump->um_extattr.uepm_list, attribute, 666 uele_entries); 667 668 VOP_UNLOCK(backing_vnode); 669 return (0); 670 671 unlock_free_exit: 672 VOP_UNLOCK(backing_vnode); 673 674 free_exit: 675 free(attribute, M_UFS_EXTATTR); 676 return (error); 677 } 678 679 /* 680 * Disable extended attribute support on an FS. 681 */ 682 static int 683 ufs_extattr_disable(struct ufsmount *ump, int attrnamespace, 684 const char *attrname, struct thread *td) 685 { 686 struct ufs_extattr_list_entry *uele; 687 int error = 0; 688 689 if (!ufs_extattr_valid_attrname(attrnamespace, attrname)) 690 return (EINVAL); 691 692 uele = ufs_extattr_find_attr(ump, attrnamespace, attrname); 693 if (!uele) 694 return (ENOATTR); 695 696 LIST_REMOVE(uele, uele_entries); 697 698 vn_lock(uele->uele_backing_vnode, LK_SHARED | LK_RETRY); 699 ASSERT_VOP_LOCKED(uele->uele_backing_vnode, "ufs_extattr_disable"); 700 VOP_UNLOCK(uele->uele_backing_vnode); 701 error = vn_close(uele->uele_backing_vnode, FREAD|FWRITE, 702 td->td_ucred, td); 703 704 free(uele, M_UFS_EXTATTR); 705 706 return (error); 707 } 708 709 /* 710 * VFS call to manage extended attributes in UFS. If filename_vp is 711 * non-NULL, it must be passed in locked, and regardless of errors in 712 * processing, will be unlocked. 713 */ 714 int 715 ufs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp, 716 int attrnamespace, const char *attrname) 717 { 718 struct ufsmount *ump = VFSTOUFS(mp); 719 struct thread *td = curthread; 720 int error; 721 722 /* 723 * Processes with privilege, but in jail, are not allowed to 724 * configure extended attributes. 725 */ 726 error = priv_check(td, PRIV_UFS_EXTATTRCTL); 727 if (error) { 728 if (filename_vp != NULL) 729 VOP_UNLOCK(filename_vp); 730 return (error); 731 } 732 733 /* 734 * We only allow extattrctl(2) on UFS1 file systems, as UFS2 uses 735 * native extended attributes. 736 */ 737 if (ump->um_fstype != UFS1) { 738 if (filename_vp != NULL) 739 VOP_UNLOCK(filename_vp); 740 return (EOPNOTSUPP); 741 } 742 743 switch(cmd) { 744 case UFS_EXTATTR_CMD_START: 745 if (filename_vp != NULL) { 746 VOP_UNLOCK(filename_vp); 747 return (EINVAL); 748 } 749 if (attrname != NULL) 750 return (EINVAL); 751 752 error = ufs_extattr_start(mp, td); 753 754 return (error); 755 756 case UFS_EXTATTR_CMD_STOP: 757 if (filename_vp != NULL) { 758 VOP_UNLOCK(filename_vp); 759 return (EINVAL); 760 } 761 if (attrname != NULL) 762 return (EINVAL); 763 764 error = ufs_extattr_stop(mp, td); 765 766 return (error); 767 768 case UFS_EXTATTR_CMD_ENABLE: 769 770 if (filename_vp == NULL) 771 return (EINVAL); 772 if (attrname == NULL) { 773 VOP_UNLOCK(filename_vp); 774 return (EINVAL); 775 } 776 777 /* 778 * ufs_extattr_enable_with_open() will always unlock the 779 * vnode, regardless of failure. 780 */ 781 ufs_extattr_uepm_lock(ump); 782 error = ufs_extattr_enable_with_open(ump, filename_vp, 783 attrnamespace, attrname, td); 784 ufs_extattr_uepm_unlock(ump); 785 786 return (error); 787 788 case UFS_EXTATTR_CMD_DISABLE: 789 790 if (filename_vp != NULL) { 791 VOP_UNLOCK(filename_vp); 792 return (EINVAL); 793 } 794 if (attrname == NULL) 795 return (EINVAL); 796 797 ufs_extattr_uepm_lock(ump); 798 error = ufs_extattr_disable(ump, attrnamespace, attrname, 799 td); 800 ufs_extattr_uepm_unlock(ump); 801 802 return (error); 803 804 default: 805 return (EINVAL); 806 } 807 } 808 809 /* 810 * Vnode operating to retrieve a named extended attribute. 811 */ 812 int 813 ufs_getextattr( 814 struct vop_getextattr_args /* { 815 IN struct vnode *a_vp; 816 IN int a_attrnamespace; 817 IN const char *a_name; 818 INOUT struct uio *a_uio; 819 OUT size_t *a_size; 820 IN struct ucred *a_cred; 821 IN struct thread *a_td; 822 } */ *ap) 823 { 824 struct mount *mp = ap->a_vp->v_mount; 825 struct ufsmount *ump = VFSTOUFS(mp); 826 int error; 827 828 ufs_extattr_uepm_lock(ump); 829 830 error = ufs_extattr_get(ap->a_vp, ap->a_attrnamespace, ap->a_name, 831 ap->a_uio, ap->a_size, ap->a_cred, ap->a_td); 832 833 ufs_extattr_uepm_unlock(ump); 834 835 return (error); 836 } 837 838 /* 839 * Real work associated with retrieving a named attribute--assumes that 840 * the attribute lock has already been grabbed. 841 */ 842 static int 843 ufs_extattr_get(struct vnode *vp, int attrnamespace, const char *name, 844 struct uio *uio, size_t *size, struct ucred *cred, struct thread *td) 845 { 846 struct ufs_extattr_list_entry *attribute; 847 struct ufs_extattr_header ueh; 848 struct iovec local_aiov; 849 struct uio local_aio; 850 struct mount *mp = vp->v_mount; 851 struct ufsmount *ump = VFSTOUFS(mp); 852 struct inode *ip = VTOI(vp); 853 off_t base_offset; 854 size_t len, old_len; 855 int error = 0; 856 857 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED)) 858 return (EOPNOTSUPP); 859 860 if (strlen(name) == 0) 861 return (EINVAL); 862 863 error = extattr_check_cred(vp, attrnamespace, cred, td, VREAD); 864 if (error) 865 return (error); 866 867 attribute = ufs_extattr_find_attr(ump, attrnamespace, name); 868 if (!attribute) 869 return (ENOATTR); 870 871 /* 872 * Allow only offsets of zero to encourage the read/replace 873 * extended attribute semantic. Otherwise we can't guarantee 874 * atomicity, as we don't provide locks for extended attributes. 875 */ 876 if (uio != NULL && uio->uio_offset != 0) 877 return (ENXIO); 878 879 /* 880 * Find base offset of header in file based on file header size, and 881 * data header size + maximum data size, indexed by inode number. 882 */ 883 base_offset = sizeof(struct ufs_extattr_fileheader) + 884 ip->i_number * (sizeof(struct ufs_extattr_header) + 885 attribute->uele_fileheader.uef_size); 886 887 /* 888 * Read in the data header to see if the data is defined, and if so 889 * how much. 890 */ 891 bzero(&ueh, sizeof(struct ufs_extattr_header)); 892 local_aiov.iov_base = (caddr_t) &ueh; 893 local_aiov.iov_len = sizeof(struct ufs_extattr_header); 894 local_aio.uio_iov = &local_aiov; 895 local_aio.uio_iovcnt = 1; 896 local_aio.uio_rw = UIO_READ; 897 local_aio.uio_segflg = UIO_SYSSPACE; 898 local_aio.uio_td = td; 899 local_aio.uio_offset = base_offset; 900 local_aio.uio_resid = sizeof(struct ufs_extattr_header); 901 902 /* 903 * Acquire locks. 904 * 905 * Don't need to get a lock on the backing file if the getattr is 906 * being applied to the backing file, as the lock is already held. 907 */ 908 if (attribute->uele_backing_vnode != vp) 909 vn_lock(attribute->uele_backing_vnode, LK_SHARED | LK_RETRY); 910 911 error = VOP_READ(attribute->uele_backing_vnode, &local_aio, 912 IO_NODELOCKED, ump->um_extattr.uepm_ucred); 913 if (error) 914 goto vopunlock_exit; 915 916 /* Defined? */ 917 if ((ueh.ueh_flags & UFS_EXTATTR_ATTR_FLAG_INUSE) == 0) { 918 error = ENOATTR; 919 goto vopunlock_exit; 920 } 921 922 /* Valid for the current inode generation? */ 923 if (ueh.ueh_i_gen != ip->i_gen) { 924 /* 925 * The inode itself has a different generation number 926 * than the attribute data. For now, the best solution 927 * is to coerce this to undefined, and let it get cleaned 928 * up by the next write or extattrctl clean. 929 */ 930 printf("ufs_extattr_get (%s): inode number inconsistency (%d, %ju)\n", 931 mp->mnt_stat.f_mntonname, ueh.ueh_i_gen, (uintmax_t)ip->i_gen); 932 error = ENOATTR; 933 goto vopunlock_exit; 934 } 935 936 /* Local size consistency check. */ 937 if (ueh.ueh_len > attribute->uele_fileheader.uef_size) { 938 error = ENXIO; 939 goto vopunlock_exit; 940 } 941 942 /* Return full data size if caller requested it. */ 943 if (size != NULL) 944 *size = ueh.ueh_len; 945 946 /* Return data if the caller requested it. */ 947 if (uio != NULL) { 948 /* Allow for offset into the attribute data. */ 949 uio->uio_offset = base_offset + sizeof(struct 950 ufs_extattr_header); 951 952 /* 953 * Figure out maximum to transfer -- use buffer size and 954 * local data limit. 955 */ 956 len = MIN(uio->uio_resid, ueh.ueh_len); 957 old_len = uio->uio_resid; 958 uio->uio_resid = len; 959 960 error = VOP_READ(attribute->uele_backing_vnode, uio, 961 IO_NODELOCKED, ump->um_extattr.uepm_ucred); 962 if (error) 963 goto vopunlock_exit; 964 965 uio->uio_resid = old_len - (len - uio->uio_resid); 966 } 967 968 vopunlock_exit: 969 970 if (uio != NULL) 971 uio->uio_offset = 0; 972 973 if (attribute->uele_backing_vnode != vp) 974 VOP_UNLOCK(attribute->uele_backing_vnode); 975 976 return (error); 977 } 978 979 /* 980 * Vnode operation to remove a named attribute. 981 */ 982 int 983 ufs_deleteextattr( 984 struct vop_deleteextattr_args /* { 985 IN struct vnode *a_vp; 986 IN int a_attrnamespace; 987 IN const char *a_name; 988 IN struct ucred *a_cred; 989 IN struct thread *a_td; 990 } */ *ap) 991 { 992 struct mount *mp = ap->a_vp->v_mount; 993 struct ufsmount *ump = VFSTOUFS(mp); 994 int error; 995 996 ufs_extattr_uepm_lock(ump); 997 998 error = ufs_extattr_rm(ap->a_vp, ap->a_attrnamespace, ap->a_name, 999 ap->a_cred, ap->a_td); 1000 1001 ufs_extattr_uepm_unlock(ump); 1002 1003 return (error); 1004 } 1005 1006 /* 1007 * Vnode operation to set a named attribute. 1008 */ 1009 int 1010 ufs_setextattr( 1011 struct vop_setextattr_args /* { 1012 IN struct vnode *a_vp; 1013 IN int a_attrnamespace; 1014 IN const char *a_name; 1015 INOUT struct uio *a_uio; 1016 IN struct ucred *a_cred; 1017 IN struct thread *a_td; 1018 } */ *ap) 1019 { 1020 struct mount *mp = ap->a_vp->v_mount; 1021 struct ufsmount *ump = VFSTOUFS(mp); 1022 int error; 1023 1024 /* 1025 * XXX: No longer a supported way to delete extended attributes. 1026 */ 1027 if (ap->a_uio == NULL) 1028 return (EINVAL); 1029 1030 ufs_extattr_uepm_lock(ump); 1031 1032 error = ufs_extattr_set(ap->a_vp, ap->a_attrnamespace, ap->a_name, 1033 ap->a_uio, ap->a_cred, ap->a_td); 1034 1035 ufs_extattr_uepm_unlock(ump); 1036 1037 return (error); 1038 } 1039 1040 /* 1041 * Real work associated with setting a vnode's extended attributes; 1042 * assumes that the attribute lock has already been grabbed. 1043 */ 1044 static int 1045 ufs_extattr_set(struct vnode *vp, int attrnamespace, const char *name, 1046 struct uio *uio, struct ucred *cred, struct thread *td) 1047 { 1048 struct ufs_extattr_list_entry *attribute; 1049 struct ufs_extattr_header ueh; 1050 struct iovec local_aiov; 1051 struct uio local_aio; 1052 struct mount *mp = vp->v_mount; 1053 struct ufsmount *ump = VFSTOUFS(mp); 1054 struct inode *ip = VTOI(vp); 1055 off_t base_offset; 1056 int error = 0, ioflag; 1057 1058 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1059 return (EROFS); 1060 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED)) 1061 return (EOPNOTSUPP); 1062 if (!ufs_extattr_valid_attrname(attrnamespace, name)) 1063 return (EINVAL); 1064 1065 error = extattr_check_cred(vp, attrnamespace, cred, td, VWRITE); 1066 if (error) 1067 return (error); 1068 1069 attribute = ufs_extattr_find_attr(ump, attrnamespace, name); 1070 if (!attribute) 1071 return (ENOATTR); 1072 1073 /* 1074 * Early rejection of invalid offsets/length. 1075 * Reject: any offset but 0 (replace) 1076 * Any size greater than attribute size limit 1077 */ 1078 if (uio->uio_offset != 0 || 1079 uio->uio_resid > attribute->uele_fileheader.uef_size) 1080 return (ENXIO); 1081 1082 /* 1083 * Find base offset of header in file based on file header size, and 1084 * data header size + maximum data size, indexed by inode number. 1085 */ 1086 base_offset = sizeof(struct ufs_extattr_fileheader) + 1087 ip->i_number * (sizeof(struct ufs_extattr_header) + 1088 attribute->uele_fileheader.uef_size); 1089 1090 /* 1091 * Write out a data header for the data. 1092 */ 1093 ueh.ueh_len = uio->uio_resid; 1094 ueh.ueh_flags = UFS_EXTATTR_ATTR_FLAG_INUSE; 1095 ueh.ueh_i_gen = ip->i_gen; 1096 local_aiov.iov_base = (caddr_t) &ueh; 1097 local_aiov.iov_len = sizeof(struct ufs_extattr_header); 1098 local_aio.uio_iov = &local_aiov; 1099 local_aio.uio_iovcnt = 1; 1100 local_aio.uio_rw = UIO_WRITE; 1101 local_aio.uio_segflg = UIO_SYSSPACE; 1102 local_aio.uio_td = td; 1103 local_aio.uio_offset = base_offset; 1104 local_aio.uio_resid = sizeof(struct ufs_extattr_header); 1105 1106 /* 1107 * Acquire locks. 1108 * 1109 * Don't need to get a lock on the backing file if the setattr is 1110 * being applied to the backing file, as the lock is already held. 1111 */ 1112 if (attribute->uele_backing_vnode != vp) 1113 vn_lock(attribute->uele_backing_vnode, LK_EXCLUSIVE | LK_RETRY); 1114 1115 ioflag = IO_NODELOCKED; 1116 if (ufs_extattr_sync) 1117 ioflag |= IO_SYNC; 1118 error = VOP_WRITE(attribute->uele_backing_vnode, &local_aio, ioflag, 1119 ump->um_extattr.uepm_ucred); 1120 if (error) 1121 goto vopunlock_exit; 1122 1123 if (local_aio.uio_resid != 0) { 1124 error = ENXIO; 1125 goto vopunlock_exit; 1126 } 1127 1128 /* 1129 * Write out user data. 1130 */ 1131 uio->uio_offset = base_offset + sizeof(struct ufs_extattr_header); 1132 1133 ioflag = IO_NODELOCKED; 1134 if (ufs_extattr_sync) 1135 ioflag |= IO_SYNC; 1136 error = VOP_WRITE(attribute->uele_backing_vnode, uio, ioflag, 1137 ump->um_extattr.uepm_ucred); 1138 1139 vopunlock_exit: 1140 uio->uio_offset = 0; 1141 1142 if (attribute->uele_backing_vnode != vp) 1143 VOP_UNLOCK(attribute->uele_backing_vnode); 1144 1145 return (error); 1146 } 1147 1148 /* 1149 * Real work associated with removing an extended attribute from a vnode. 1150 * Assumes the attribute lock has already been grabbed. 1151 */ 1152 static int 1153 ufs_extattr_rm(struct vnode *vp, int attrnamespace, const char *name, 1154 struct ucred *cred, struct thread *td) 1155 { 1156 struct ufs_extattr_list_entry *attribute; 1157 struct ufs_extattr_header ueh; 1158 struct iovec local_aiov; 1159 struct uio local_aio; 1160 struct mount *mp = vp->v_mount; 1161 struct ufsmount *ump = VFSTOUFS(mp); 1162 struct inode *ip = VTOI(vp); 1163 off_t base_offset; 1164 int error = 0, ioflag; 1165 1166 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1167 return (EROFS); 1168 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED)) 1169 return (EOPNOTSUPP); 1170 if (!ufs_extattr_valid_attrname(attrnamespace, name)) 1171 return (EINVAL); 1172 1173 error = extattr_check_cred(vp, attrnamespace, cred, td, VWRITE); 1174 if (error) 1175 return (error); 1176 1177 attribute = ufs_extattr_find_attr(ump, attrnamespace, name); 1178 if (!attribute) 1179 return (ENOATTR); 1180 1181 /* 1182 * Find base offset of header in file based on file header size, and 1183 * data header size + maximum data size, indexed by inode number. 1184 */ 1185 base_offset = sizeof(struct ufs_extattr_fileheader) + 1186 ip->i_number * (sizeof(struct ufs_extattr_header) + 1187 attribute->uele_fileheader.uef_size); 1188 1189 /* 1190 * Check to see if currently defined. 1191 */ 1192 bzero(&ueh, sizeof(struct ufs_extattr_header)); 1193 1194 local_aiov.iov_base = (caddr_t) &ueh; 1195 local_aiov.iov_len = sizeof(struct ufs_extattr_header); 1196 local_aio.uio_iov = &local_aiov; 1197 local_aio.uio_iovcnt = 1; 1198 local_aio.uio_rw = UIO_READ; 1199 local_aio.uio_segflg = UIO_SYSSPACE; 1200 local_aio.uio_td = td; 1201 local_aio.uio_offset = base_offset; 1202 local_aio.uio_resid = sizeof(struct ufs_extattr_header); 1203 1204 /* 1205 * Don't need to get the lock on the backing vnode if the vnode we're 1206 * modifying is it, as we already hold the lock. 1207 */ 1208 if (attribute->uele_backing_vnode != vp) 1209 vn_lock(attribute->uele_backing_vnode, LK_EXCLUSIVE | LK_RETRY); 1210 1211 error = VOP_READ(attribute->uele_backing_vnode, &local_aio, 1212 IO_NODELOCKED, ump->um_extattr.uepm_ucred); 1213 if (error) 1214 goto vopunlock_exit; 1215 1216 /* Defined? */ 1217 if ((ueh.ueh_flags & UFS_EXTATTR_ATTR_FLAG_INUSE) == 0) { 1218 error = ENOATTR; 1219 goto vopunlock_exit; 1220 } 1221 1222 /* Valid for the current inode generation? */ 1223 if (ueh.ueh_i_gen != ip->i_gen) { 1224 /* 1225 * The inode itself has a different generation number than 1226 * the attribute data. For now, the best solution is to 1227 * coerce this to undefined, and let it get cleaned up by 1228 * the next write or extattrctl clean. 1229 */ 1230 printf("ufs_extattr_rm (%s): inode number inconsistency (%d, %jd)\n", 1231 mp->mnt_stat.f_mntonname, ueh.ueh_i_gen, (intmax_t)ip->i_gen); 1232 error = ENOATTR; 1233 goto vopunlock_exit; 1234 } 1235 1236 /* Flag it as not in use. */ 1237 ueh.ueh_flags = 0; 1238 ueh.ueh_len = 0; 1239 1240 local_aiov.iov_base = (caddr_t) &ueh; 1241 local_aiov.iov_len = sizeof(struct ufs_extattr_header); 1242 local_aio.uio_iov = &local_aiov; 1243 local_aio.uio_iovcnt = 1; 1244 local_aio.uio_rw = UIO_WRITE; 1245 local_aio.uio_segflg = UIO_SYSSPACE; 1246 local_aio.uio_td = td; 1247 local_aio.uio_offset = base_offset; 1248 local_aio.uio_resid = sizeof(struct ufs_extattr_header); 1249 1250 ioflag = IO_NODELOCKED; 1251 if (ufs_extattr_sync) 1252 ioflag |= IO_SYNC; 1253 error = VOP_WRITE(attribute->uele_backing_vnode, &local_aio, ioflag, 1254 ump->um_extattr.uepm_ucred); 1255 if (error) 1256 goto vopunlock_exit; 1257 1258 if (local_aio.uio_resid != 0) 1259 error = ENXIO; 1260 1261 vopunlock_exit: 1262 VOP_UNLOCK(attribute->uele_backing_vnode); 1263 1264 return (error); 1265 } 1266 1267 /* 1268 * Called by UFS when an inode is no longer active and should have its 1269 * attributes stripped. 1270 */ 1271 void 1272 ufs_extattr_vnode_inactive(struct vnode *vp) 1273 { 1274 struct ufs_extattr_list_entry *uele; 1275 struct mount *mp = vp->v_mount; 1276 struct ufsmount *ump = VFSTOUFS(mp); 1277 1278 /* 1279 * In that case, we cannot lock. We should not have any active vnodes 1280 * on the fs if this is not yet initialized but is going to be, so 1281 * this can go unlocked. 1282 */ 1283 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_INITIALIZED)) 1284 return; 1285 1286 ufs_extattr_uepm_lock(ump); 1287 1288 if (!(ump->um_extattr.uepm_flags & UFS_EXTATTR_UEPM_STARTED)) { 1289 ufs_extattr_uepm_unlock(ump); 1290 return; 1291 } 1292 1293 LIST_FOREACH(uele, &ump->um_extattr.uepm_list, uele_entries) 1294 ufs_extattr_rm(vp, uele->uele_attrnamespace, 1295 uele->uele_attrname, NULL, curthread); 1296 1297 ufs_extattr_uepm_unlock(ump); 1298 } 1299 1300 #endif /* !UFS_EXTATTR */ 1301