1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 /* 29 * vnode ops for the devfs 30 * 31 * For leaf vnode special files (VCHR|VBLK) specfs will always see the VOP 32 * first because dv_find always performs leaf vnode substitution, returning 33 * a specfs vnode with an s_realvp pointing to the devfs leaf vnode. This 34 * means that the only leaf special file VOP operations that devfs will see 35 * after VOP_LOOKUP are the ones that specfs forwards. 36 */ 37 38 #include <sys/types.h> 39 #include <sys/param.h> 40 #include <sys/t_lock.h> 41 #include <sys/systm.h> 42 #include <sys/sysmacros.h> 43 #include <sys/user.h> 44 #include <sys/time.h> 45 #include <sys/vfs.h> 46 #include <sys/vnode.h> 47 #include <sys/vfs_opreg.h> 48 #include <sys/file.h> 49 #include <sys/fcntl.h> 50 #include <sys/flock.h> 51 #include <sys/kmem.h> 52 #include <sys/uio.h> 53 #include <sys/errno.h> 54 #include <sys/stat.h> 55 #include <sys/cred.h> 56 #include <sys/dirent.h> 57 #include <sys/pathname.h> 58 #include <sys/cmn_err.h> 59 #include <sys/debug.h> 60 #include <sys/policy.h> 61 #include <sys/modctl.h> 62 63 #include <fs/fs_subr.h> 64 #include <sys/fs/dv_node.h> 65 66 extern struct vattr dv_vattr_dir, dv_vattr_file; 67 extern dev_t rconsdev; 68 69 /* 70 * Open of devices (leaf nodes) is handled by specfs. 71 * There is nothing to do to open a directory 72 */ 73 /*ARGSUSED*/ 74 static int 75 devfs_open(struct vnode **vpp, int flag, struct cred *cred, 76 caller_context_t *ct) 77 { 78 struct dv_node *dv = VTODV(*vpp); 79 80 dcmn_err2(("devfs_open %s\n", dv->dv_name)); 81 ASSERT((*vpp)->v_type == VDIR); 82 return (0); 83 } 84 85 /* 86 * Close of devices (leaf nodes) is handled by specfs. 87 * There is nothing much to do inorder to close a directory. 88 */ 89 /*ARGSUSED1*/ 90 static int 91 devfs_close(struct vnode *vp, int flag, int count, 92 offset_t offset, struct cred *cred, caller_context_t *ct) 93 { 94 struct dv_node *dv = VTODV(vp); 95 96 dcmn_err2(("devfs_close %s\n", dv->dv_name)); 97 ASSERT(vp->v_type == VDIR); 98 99 cleanlocks(vp, ttoproc(curthread)->p_pid, 0); 100 cleanshares(vp, ttoproc(curthread)->p_pid); 101 return (0); 102 } 103 104 /* 105 * Read of devices (leaf nodes) is handled by specfs. 106 * Read of directories is not supported. 107 */ 108 /*ARGSUSED*/ 109 static int 110 devfs_read(struct vnode *vp, struct uio *uiop, int ioflag, struct cred *cred, 111 struct caller_context *ct) 112 { 113 dcmn_err2(("devfs_read %s\n", VTODV(vp)->dv_name)); 114 ASSERT(vp->v_type == VDIR); 115 ASSERT(RW_READ_HELD(&VTODV(vp)->dv_contents)); 116 return (EISDIR); 117 } 118 119 /* 120 * Write of devices (leaf nodes) is handled by specfs. 121 * Write of directories is not supported. 122 */ 123 /*ARGSUSED*/ 124 static int 125 devfs_write(struct vnode *vp, struct uio *uiop, int ioflag, struct cred *cred, 126 struct caller_context *ct) 127 { 128 dcmn_err2(("devfs_write %s\n", VTODV(vp)->dv_name)); 129 ASSERT(vp->v_type == VDIR); 130 ASSERT(RW_WRITE_HELD(&VTODV(vp)->dv_contents)); 131 return (EISDIR); 132 } 133 134 /* 135 * Ioctls to device (leaf nodes) is handled by specfs. 136 * Ioctl to directories is not supported. 137 */ 138 /*ARGSUSED*/ 139 static int 140 devfs_ioctl(struct vnode *vp, int cmd, intptr_t arg, int flag, 141 struct cred *cred, int *rvalp, caller_context_t *ct) 142 { 143 dcmn_err2(("devfs_ioctl %s\n", VTODV(vp)->dv_name)); 144 ASSERT(vp->v_type == VDIR); 145 146 return (ENOTTY); /* no ioctls supported */ 147 } 148 149 /* 150 * We can be asked directly about the attributes of directories, or 151 * (via sp->s_realvp) about the filesystem attributes of special files. 152 * 153 * For directories, we just believe the attribute store 154 * though we mangle the nodeid, fsid, and rdev to convince userland we 155 * really are a different filesystem. 156 * 157 * For special files, a little more fakery is required. 158 * 159 * If the attribute store is not there (read only root), we believe our 160 * memory based attributes. 161 */ 162 static int 163 devfs_getattr(struct vnode *vp, struct vattr *vap, int flags, struct cred *cr, 164 caller_context_t *ct) 165 { 166 struct dv_node *dv = VTODV(vp); 167 int error = 0; 168 uint_t mask; 169 170 /* 171 * Message goes to console only. Otherwise, the message 172 * causes devfs_getattr to be invoked again... infinite loop 173 */ 174 dcmn_err2(("?devfs_getattr %s\n", dv->dv_name)); 175 ASSERT(dv->dv_attr || dv->dv_attrvp); 176 177 if (!(vp->v_type == VDIR || vp->v_type == VCHR || vp->v_type == VBLK)) { 178 cmn_err(CE_WARN, /* panic ? */ 179 "?%s: getattr on vnode type %d", dvnm, vp->v_type); 180 return (ENOENT); 181 } 182 183 rw_enter(&dv->dv_contents, RW_READER); 184 if (dv->dv_attr) { 185 /* 186 * obtain from the memory version of attribute. 187 * preserve mask for those that optimize. 188 * devfs specific fields are already merged on creation. 189 */ 190 mask = vap->va_mask; 191 *vap = *dv->dv_attr; 192 vap->va_mask = mask; 193 } else { 194 /* obtain from attribute store and merge */ 195 error = VOP_GETATTR(dv->dv_attrvp, vap, flags, cr, ct); 196 dsysdebug(error, ("vop_getattr %s %d\n", dv->dv_name, error)); 197 dv_vattr_merge(dv, vap); 198 } 199 rw_exit(&dv->dv_contents); 200 201 /* 202 * Restrict the permissions of the node fronting the console 203 * to 0600 with root as the owner. This prevents a non-root 204 * user from gaining access to a serial terminal (like /dev/term/a) 205 * which is in reality serving as the console device (/dev/console). 206 */ 207 if (vp->v_rdev == rconsdev) { 208 mode_t rconsmask = S_IXUSR|S_IRWXG|S_IRWXO; 209 vap->va_mode &= (~rconsmask); 210 vap->va_uid = 0; 211 } 212 213 return (error); 214 } 215 216 static int devfs_unlocked_access(void *, int, struct cred *); 217 218 /*ARGSUSED4*/ 219 static int 220 devfs_setattr_dir( 221 struct dv_node *dv, 222 struct vnode *vp, 223 struct vattr *vap, 224 int flags, 225 struct cred *cr) 226 { 227 struct vattr *map; 228 long int mask; 229 int error = 0; 230 struct vattr vattr; 231 232 ASSERT(dv->dv_attr || dv->dv_attrvp); 233 234 ASSERT(vp->v_type == VDIR); 235 ASSERT((dv->dv_flags & DV_NO_FSPERM) == 0); 236 237 if (vap->va_mask & AT_NOSET) 238 return (EINVAL); 239 240 /* to ensure consistency, single thread setting of attributes */ 241 rw_enter(&dv->dv_contents, RW_WRITER); 242 243 again: if (dv->dv_attr) { 244 245 error = secpolicy_vnode_setattr(cr, vp, vap, 246 dv->dv_attr, flags, devfs_unlocked_access, dv); 247 248 if (error) 249 goto out; 250 251 /* 252 * Apply changes to the memory based attribute. This code 253 * is modeled after the tmpfs implementation of memory 254 * based vnodes 255 */ 256 map = dv->dv_attr; 257 mask = vap->va_mask; 258 259 /* Change file access modes. */ 260 if (mask & AT_MODE) { 261 map->va_mode &= S_IFMT; 262 map->va_mode |= vap->va_mode & ~S_IFMT; 263 } 264 if (mask & AT_UID) 265 map->va_uid = vap->va_uid; 266 if (mask & AT_GID) 267 map->va_gid = vap->va_gid; 268 if (mask & AT_ATIME) 269 map->va_atime = vap->va_atime; 270 if (mask & AT_MTIME) 271 map->va_mtime = vap->va_mtime; 272 273 if (mask & (AT_MODE | AT_UID | AT_GID | AT_MTIME)) 274 gethrestime(&map->va_ctime); 275 } else { 276 /* use the backing attribute store */ 277 ASSERT(dv->dv_attrvp); 278 279 /* 280 * See if we are changing something we care about 281 * the persistence of - return success if we don't care. 282 */ 283 if (vap->va_mask & (AT_MODE|AT_UID|AT_GID|AT_ATIME|AT_MTIME)) { 284 /* Set the attributes */ 285 error = VOP_SETATTR(dv->dv_attrvp, 286 vap, flags, cr, NULL); 287 dsysdebug(error, 288 ("vop_setattr %s %d\n", dv->dv_name, error)); 289 290 /* 291 * Some file systems may return EROFS for a setattr 292 * on a readonly file system. In this case we create 293 * our own memory based attribute. 294 */ 295 if (error == EROFS) { 296 /* 297 * obtain attributes from existing file 298 * that we will modify and switch to memory 299 * based attribute until attribute store is 300 * read/write. 301 */ 302 vattr = dv_vattr_dir; 303 if (VOP_GETATTR(dv->dv_attrvp, 304 &vattr, flags, cr, NULL) == 0) { 305 dv->dv_attr = kmem_alloc( 306 sizeof (struct vattr), KM_SLEEP); 307 *dv->dv_attr = vattr; 308 dv_vattr_merge(dv, dv->dv_attr); 309 goto again; 310 } 311 } 312 } 313 } 314 out: 315 rw_exit(&dv->dv_contents); 316 return (error); 317 } 318 319 320 /* 321 * Compare the uid/gid/mode changes requested for a setattr 322 * operation with the same details of a node's default minor 323 * perm information. Return 0 if identical. 324 */ 325 static int 326 dv_setattr_cmp(struct vattr *map, mperm_t *mp) 327 { 328 if ((map->va_mode & S_IAMB) != (mp->mp_mode & S_IAMB)) 329 return (1); 330 if (map->va_uid != mp->mp_uid) 331 return (1); 332 if (map->va_gid != mp->mp_gid) 333 return (1); 334 return (0); 335 } 336 337 338 /*ARGSUSED4*/ 339 static int 340 devfs_setattr( 341 struct vnode *vp, 342 struct vattr *vap, 343 int flags, 344 struct cred *cr, 345 caller_context_t *ct) 346 { 347 struct dv_node *dv = VTODV(vp); 348 struct dv_node *ddv; 349 struct vnode *dvp; 350 struct vattr *map; 351 long int mask; 352 int error = 0; 353 struct vattr *free_vattr = NULL; 354 struct vattr *vattrp = NULL; 355 mperm_t mp; 356 int persist; 357 358 /* 359 * Message goes to console only. Otherwise, the message 360 * causes devfs_getattr to be invoked again... infinite loop 361 */ 362 dcmn_err2(("?devfs_setattr %s\n", dv->dv_name)); 363 ASSERT(dv->dv_attr || dv->dv_attrvp); 364 365 if (!(vp->v_type == VDIR || vp->v_type == VCHR || vp->v_type == VBLK)) { 366 cmn_err(CE_WARN, /* panic ? */ 367 "?%s: getattr on vnode type %d", dvnm, vp->v_type); 368 return (ENOENT); 369 } 370 371 if (vap->va_mask & AT_NOSET) 372 return (EINVAL); 373 374 /* 375 * If we are changing something we don't care about 376 * the persistence of, return success. 377 */ 378 if ((vap->va_mask & 379 (AT_MODE|AT_UID|AT_GID|AT_ATIME|AT_MTIME)) == 0) 380 return (0); 381 382 /* 383 * If driver overrides fs perm, disallow chmod 384 * and do not create attribute nodes. 385 */ 386 if (dv->dv_flags & DV_NO_FSPERM) { 387 ASSERT(dv->dv_attr); 388 if (vap->va_mask & (AT_MODE | AT_UID | AT_GID)) 389 return (EPERM); 390 if ((vap->va_mask & (AT_ATIME|AT_MTIME)) == 0) 391 return (0); 392 rw_enter(&dv->dv_contents, RW_WRITER); 393 if (vap->va_mask & AT_ATIME) 394 dv->dv_attr->va_atime = vap->va_atime; 395 if (vap->va_mask & AT_MTIME) 396 dv->dv_attr->va_mtime = vap->va_mtime; 397 rw_exit(&dv->dv_contents); 398 return (0); 399 } 400 401 /* 402 * Directories are always created but device nodes are 403 * only used to persist non-default permissions. 404 */ 405 if (vp->v_type == VDIR) { 406 ASSERT(dv->dv_attr || dv->dv_attrvp); 407 return (devfs_setattr_dir(dv, vp, vap, flags, cr)); 408 } 409 410 /* 411 * Allocate now before we take any locks 412 */ 413 vattrp = kmem_zalloc(sizeof (*vattrp), KM_SLEEP); 414 415 /* to ensure consistency, single thread setting of attributes */ 416 rw_enter(&dv->dv_contents, RW_WRITER); 417 418 /* 419 * We don't need to create an attribute node 420 * to persist access or modification times. 421 */ 422 persist = (vap->va_mask & (AT_MODE | AT_UID | AT_GID)); 423 424 /* 425 * If persisting something, get the default permissions 426 * for this minor to compare against what the attributes 427 * are now being set to. Default ordering is: 428 * - minor_perm match for this minor 429 * - mode supplied by ddi_create_priv_minor_node 430 * - devfs defaults 431 */ 432 if (persist) { 433 if (dev_minorperm(dv->dv_devi, dv->dv_name, &mp) != 0) { 434 mp.mp_uid = dv_vattr_file.va_uid; 435 mp.mp_gid = dv_vattr_file.va_gid; 436 mp.mp_mode = dv_vattr_file.va_mode; 437 if (dv->dv_flags & DV_DFLT_MODE) { 438 ASSERT((dv->dv_dflt_mode & ~S_IAMB) == 0); 439 mp.mp_mode &= ~S_IAMB; 440 mp.mp_mode |= dv->dv_dflt_mode; 441 dcmn_err5(("%s: setattr priv default 0%o\n", 442 dv->dv_name, mp.mp_mode)); 443 } else { 444 dcmn_err5(("%s: setattr devfs default 0%o\n", 445 dv->dv_name, mp.mp_mode)); 446 } 447 } else { 448 dcmn_err5(("%s: setattr minor perm default 0%o\n", 449 dv->dv_name, mp.mp_mode)); 450 } 451 } 452 453 /* 454 * If we don't have a vattr for this node, construct one. 455 */ 456 if (dv->dv_attr) { 457 free_vattr = vattrp; 458 vattrp = NULL; 459 } else { 460 ASSERT(dv->dv_attrvp); 461 ASSERT(vp->v_type != VDIR); 462 *vattrp = dv_vattr_file; 463 error = VOP_GETATTR(dv->dv_attrvp, vattrp, 0, cr, ct); 464 dsysdebug(error, ("vop_getattr %s %d\n", dv->dv_name, error)); 465 if (error) 466 goto out; 467 dv->dv_attr = vattrp; 468 dv_vattr_merge(dv, dv->dv_attr); 469 vattrp = NULL; 470 } 471 472 error = secpolicy_vnode_setattr(cr, vp, vap, dv->dv_attr, 473 flags, devfs_unlocked_access, dv); 474 if (error) { 475 dsysdebug(error, ("devfs_setattr %s secpolicy error %d\n", 476 dv->dv_name, error)); 477 goto out; 478 } 479 480 /* 481 * Apply changes to the memory based attribute. This code 482 * is modeled after the tmpfs implementation of memory 483 * based vnodes 484 */ 485 map = dv->dv_attr; 486 mask = vap->va_mask; 487 488 /* Change file access modes. */ 489 if (mask & AT_MODE) { 490 map->va_mode &= S_IFMT; 491 map->va_mode |= vap->va_mode & ~S_IFMT; 492 } 493 if (mask & AT_UID) 494 map->va_uid = vap->va_uid; 495 if (mask & AT_GID) 496 map->va_gid = vap->va_gid; 497 if (mask & AT_ATIME) 498 map->va_atime = vap->va_atime; 499 if (mask & AT_MTIME) 500 map->va_mtime = vap->va_mtime; 501 502 if (mask & (AT_MODE | AT_UID | AT_GID | AT_MTIME)) { 503 gethrestime(&map->va_ctime); 504 } 505 506 /* 507 * A setattr to defaults means we no longer need the 508 * shadow node as a persistent store, unless there 509 * are ACLs. Otherwise create a shadow node if one 510 * doesn't exist yet. 511 */ 512 if (persist) { 513 if ((dv_setattr_cmp(map, &mp) == 0) && 514 ((dv->dv_flags & DV_ACL) == 0)) { 515 516 if (dv->dv_attrvp) { 517 ddv = dv->dv_dotdot; 518 ASSERT(ddv->dv_attrvp); 519 error = VOP_REMOVE(ddv->dv_attrvp, 520 dv->dv_name, cr, ct, 0); 521 dsysdebug(error, 522 ("vop_remove %s %s %d\n", 523 ddv->dv_name, dv->dv_name, error)); 524 525 if (error == EROFS) 526 error = 0; 527 VN_RELE(dv->dv_attrvp); 528 dv->dv_attrvp = NULL; 529 } 530 ASSERT(dv->dv_attr); 531 } else { 532 if (mask & AT_MODE) 533 dcmn_err5(("%s persisting mode 0%o\n", 534 dv->dv_name, vap->va_mode)); 535 if (mask & AT_UID) 536 dcmn_err5(("%s persisting uid %d\n", 537 dv->dv_name, vap->va_uid)); 538 if (mask & AT_GID) 539 dcmn_err5(("%s persisting gid %d\n", 540 dv->dv_name, vap->va_gid)); 541 542 if (dv->dv_attrvp == NULL) { 543 dvp = DVTOV(dv->dv_dotdot); 544 dv_shadow_node(dvp, dv->dv_name, vp, 545 NULL, NULLVP, cr, 546 DV_SHADOW_CREATE | DV_SHADOW_WRITE_HELD); 547 } 548 if (dv->dv_attrvp) { 549 error = VOP_SETATTR(dv->dv_attrvp, 550 vap, flags, cr, NULL); 551 dsysdebug(error, ("vop_setattr %s %d\n", 552 dv->dv_name, error)); 553 } 554 /* 555 * Some file systems may return EROFS for a setattr 556 * on a readonly file system. In this case save 557 * as our own memory based attribute. 558 * NOTE: ufs is NOT one of these (see ufs_iupdat). 559 */ 560 if (dv->dv_attr && dv->dv_attrvp && error == 0) { 561 vattrp = dv->dv_attr; 562 dv->dv_attr = NULL; 563 } else if (error == EROFS) 564 error = 0; 565 } 566 } 567 568 out: 569 rw_exit(&dv->dv_contents); 570 571 if (vattrp) 572 kmem_free(vattrp, sizeof (*vattrp)); 573 if (free_vattr) 574 kmem_free(free_vattr, sizeof (*free_vattr)); 575 return (error); 576 } 577 578 static int 579 devfs_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr, 580 caller_context_t *ct) 581 { 582 switch (cmd) { 583 case _PC_ACL_ENABLED: 584 /* 585 * We rely on the underlying filesystem for ACLs, 586 * so direct the query for ACL support there. 587 * ACL support isn't relative to the file 588 * and we can't guarantee that the dv node 589 * has an attribute node, so any valid 590 * attribute node will suffice. 591 */ 592 ASSERT(dvroot); 593 ASSERT(dvroot->dv_attrvp); 594 return (VOP_PATHCONF(dvroot->dv_attrvp, cmd, valp, cr, ct)); 595 /*NOTREACHED*/ 596 } 597 598 return (fs_pathconf(vp, cmd, valp, cr, ct)); 599 } 600 601 /* 602 * Let avp handle security attributes (acl's). 603 */ 604 static int 605 devfs_getsecattr(struct vnode *vp, struct vsecattr *vsap, int flags, 606 struct cred *cr, caller_context_t *ct) 607 { 608 dvnode_t *dv = VTODV(vp); 609 struct vnode *avp; 610 int error; 611 612 dcmn_err2(("devfs_getsecattr %s\n", dv->dv_name)); 613 ASSERT(vp->v_type == VDIR || vp->v_type == VCHR || vp->v_type == VBLK); 614 615 rw_enter(&dv->dv_contents, RW_READER); 616 617 avp = dv->dv_attrvp; 618 619 /* fabricate the acl */ 620 if (avp == NULL) { 621 error = fs_fab_acl(vp, vsap, flags, cr, ct); 622 rw_exit(&dv->dv_contents); 623 return (error); 624 } 625 626 error = VOP_GETSECATTR(avp, vsap, flags, cr, ct); 627 dsysdebug(error, ("vop_getsecattr %s %d\n", VTODV(vp)->dv_name, error)); 628 rw_exit(&dv->dv_contents); 629 return (error); 630 } 631 632 /* 633 * Set security attributes (acl's) 634 * 635 * Note that the dv_contents lock has already been acquired 636 * by the caller's VOP_RWLOCK. 637 */ 638 static int 639 devfs_setsecattr(struct vnode *vp, struct vsecattr *vsap, int flags, 640 struct cred *cr, caller_context_t *ct) 641 { 642 dvnode_t *dv = VTODV(vp); 643 struct vnode *avp; 644 int error; 645 646 dcmn_err2(("devfs_setsecattr %s\n", dv->dv_name)); 647 ASSERT(vp->v_type == VDIR || vp->v_type == VCHR || vp->v_type == VBLK); 648 ASSERT(RW_LOCK_HELD(&dv->dv_contents)); 649 650 /* 651 * Not a supported operation on drivers not providing 652 * file system based permissions. 653 */ 654 if (dv->dv_flags & DV_NO_FSPERM) 655 return (ENOTSUP); 656 657 /* 658 * To complete, the setsecattr requires an underlying attribute node. 659 */ 660 if (dv->dv_attrvp == NULL) { 661 ASSERT(vp->v_type == VCHR || vp->v_type == VBLK); 662 dv_shadow_node(DVTOV(dv->dv_dotdot), dv->dv_name, vp, 663 NULL, NULLVP, cr, DV_SHADOW_CREATE | DV_SHADOW_WRITE_HELD); 664 } 665 666 if ((avp = dv->dv_attrvp) == NULL) { 667 dcmn_err2(("devfs_setsecattr %s: " 668 "cannot construct attribute node\n", dv->dv_name)); 669 return (fs_nosys()); 670 } 671 672 /* 673 * The acl(2) system call issues a VOP_RWLOCK before setting an ACL. 674 * Since backing file systems expect the lock to be held before seeing 675 * a VOP_SETSECATTR ACL, we need to issue the VOP_RWLOCK to the backing 676 * store before forwarding the ACL. 677 */ 678 (void) VOP_RWLOCK(avp, V_WRITELOCK_TRUE, NULL); 679 error = VOP_SETSECATTR(avp, vsap, flags, cr, ct); 680 dsysdebug(error, ("vop_setsecattr %s %d\n", VTODV(vp)->dv_name, error)); 681 VOP_RWUNLOCK(avp, V_WRITELOCK_TRUE, NULL); 682 683 /* 684 * Set DV_ACL if we have a non-trivial set of ACLs. It is not 685 * necessary to hold VOP_RWLOCK since fs_acl_nontrivial only does 686 * VOP_GETSECATTR calls. 687 */ 688 if (fs_acl_nontrivial(avp, cr)) 689 dv->dv_flags |= DV_ACL; 690 return (error); 691 } 692 693 /* 694 * This function is used for secpolicy_setattr(). It must call an 695 * access() like function while it is already holding the 696 * dv_contents lock. We only care about this when dv_attr != NULL; 697 * so the unlocked access call only concerns itself with that 698 * particular branch of devfs_access(). 699 */ 700 static int 701 devfs_unlocked_access(void *vdv, int mode, struct cred *cr) 702 { 703 struct dv_node *dv = vdv; 704 int shift = 0; 705 uid_t owner = dv->dv_attr->va_uid; 706 707 /* Check access based on owner, group and public permissions. */ 708 if (crgetuid(cr) != owner) { 709 shift += 3; 710 if (groupmember(dv->dv_attr->va_gid, cr) == 0) 711 shift += 3; 712 } 713 714 /* compute missing mode bits */ 715 mode &= ~(dv->dv_attr->va_mode << shift); 716 717 if (mode == 0) 718 return (0); 719 720 return (secpolicy_vnode_access(cr, DVTOV(dv), owner, mode)); 721 } 722 723 static int 724 devfs_access(struct vnode *vp, int mode, int flags, struct cred *cr, 725 caller_context_t *ct) 726 { 727 struct dv_node *dv = VTODV(vp); 728 int res; 729 730 dcmn_err2(("devfs_access %s\n", dv->dv_name)); 731 ASSERT(dv->dv_attr || dv->dv_attrvp); 732 733 /* restrict console access to privileged processes */ 734 if ((vp->v_rdev == rconsdev) && secpolicy_console(cr) != 0) { 735 return (EACCES); 736 } 737 738 rw_enter(&dv->dv_contents, RW_READER); 739 if (dv->dv_attr && ((dv->dv_flags & DV_ACL) == 0)) { 740 res = devfs_unlocked_access(dv, mode, cr); 741 } else { 742 res = VOP_ACCESS(dv->dv_attrvp, mode, flags, cr, ct); 743 } 744 rw_exit(&dv->dv_contents); 745 return (res); 746 } 747 748 /* 749 * Lookup 750 * 751 * Given the directory vnode and the name of the component, return 752 * the corresponding held vnode for that component. 753 * 754 * Of course in these fictional filesystems, nothing's ever quite 755 * -that- simple. 756 * 757 * devfs name type shadow (fs attributes) type comments 758 * ------------------------------------------------------------------------- 759 * drv[@addr] VDIR drv[@addr] VDIR nexus driver 760 * drv[@addr]:m VCHR/VBLK drv[@addr]:m VREG leaf driver 761 * drv[@addr] VCHR/VBLK drv[@addr]:.default VREG leaf driver 762 * ------------------------------------------------------------------------- 763 * 764 * The following names are reserved for the attribute filesystem (which 765 * could easily be another layer on top of this one - we simply need to 766 * hold the vnode of the thing we're looking at) 767 * 768 * attr name type shadow (fs attributes) type comments 769 * ------------------------------------------------------------------------- 770 * drv[@addr] VDIR - - attribute dir 771 * minorname VDIR - - minorname 772 * attribute VREG - - attribute 773 * ------------------------------------------------------------------------- 774 * 775 * Examples: 776 * 777 * devfs:/devices/.../mm@0:zero VCHR 778 * shadow:/.devices/.../mm@0:zero VREG, fs attrs 779 * devfs:/devices/.../mm@0:/zero/attr VREG, driver attribute 780 * 781 * devfs:/devices/.../sd@0,0:a VBLK 782 * shadow:/.devices/.../sd@0,0:a VREG, fs attrs 783 * devfs:/devices/.../sd@0,0:/a/.type VREG, "ddi_block:chan" 784 * 785 * devfs:/devices/.../mm@0 VCHR 786 * shadow:/.devices/.../mm@0:.default VREG, fs attrs 787 * devfs:/devices/.../mm@0:/.default/attr VREG, driver attribute 788 * devfs:/devices/.../mm@0:/.default/.type VREG, "ddi_pseudo" 789 * 790 * devfs:/devices/.../obio VDIR 791 * shadow:/devices/.../obio VDIR, needed for fs attrs. 792 * devfs:/devices/.../obio:/.default/attr VDIR, driver attribute 793 * 794 * We also need to be able deal with "old" devices that have gone away, 795 * though I think that provided we return them with readdir, they can 796 * be removed (i.e. they don't have to respond to lookup, though it might 797 * be weird if they didn't ;-) 798 * 799 * Lookup has side-effects. 800 * 801 * - It will create directories and fs attribute files in the shadow hierarchy. 802 * - It should cause non-SID devices to be probed (ask the parent nexi). 803 */ 804 /*ARGSUSED3*/ 805 static int 806 devfs_lookup(struct vnode *dvp, char *nm, struct vnode **vpp, 807 struct pathname *pnp, int flags, struct vnode *rdir, struct cred *cred, 808 caller_context_t *ct, int *direntflags, pathname_t *realpnp) 809 { 810 ASSERT(dvp->v_type == VDIR); 811 dcmn_err2(("devfs_lookup: %s\n", nm)); 812 return (dv_find(VTODV(dvp), nm, vpp, pnp, rdir, cred, 0)); 813 } 814 815 /* 816 * devfs nodes can't really be created directly by userland - however, 817 * we do allow creates to find existing nodes: 818 * 819 * - any create fails if the node doesn't exist - EROFS. 820 * - creating an existing directory read-only succeeds, otherwise EISDIR. 821 * - exclusive creates fail if the node already exists - EEXIST. 822 * - failure to create the snode for an existing device - ENOSYS. 823 */ 824 /*ARGSUSED2*/ 825 static int 826 devfs_create(struct vnode *dvp, char *nm, struct vattr *vap, vcexcl_t excl, 827 int mode, struct vnode **vpp, struct cred *cred, int flag, 828 caller_context_t *ct, vsecattr_t *vsecp) 829 { 830 int error; 831 struct vnode *vp; 832 833 dcmn_err2(("devfs_create %s\n", nm)); 834 error = dv_find(VTODV(dvp), nm, &vp, NULL, NULLVP, cred, 0); 835 if (error == 0) { 836 if (excl == EXCL) 837 error = EEXIST; 838 else if (vp->v_type == VDIR && (mode & VWRITE)) 839 error = EISDIR; 840 else 841 error = VOP_ACCESS(vp, mode, 0, cred, ct); 842 843 if (error) { 844 VN_RELE(vp); 845 } else 846 *vpp = vp; 847 } else if (error == ENOENT) 848 error = EROFS; 849 850 return (error); 851 } 852 853 /* 854 * If DV_BUILD is set, we call into nexus driver to do a BUS_CONFIG_ALL. 855 * Otherwise, simply return cached dv_node's. Hotplug code always call 856 * devfs_clean() to invalid the dv_node cache. 857 */ 858 /*ARGSUSED5*/ 859 static int 860 devfs_readdir(struct vnode *dvp, struct uio *uiop, struct cred *cred, int *eofp, 861 caller_context_t *ct, int flags) 862 { 863 struct dv_node *ddv, *dv; 864 struct dirent64 *de, *bufp; 865 offset_t diroff; 866 offset_t soff; 867 size_t reclen, movesz; 868 int error; 869 struct vattr va; 870 size_t bufsz; 871 872 ddv = VTODV(dvp); 873 dcmn_err2(("devfs_readdir %s: offset %lld len %ld\n", 874 ddv->dv_name, uiop->uio_loffset, uiop->uio_iov->iov_len)); 875 ASSERT(ddv->dv_attr || ddv->dv_attrvp); 876 ASSERT(RW_READ_HELD(&ddv->dv_contents)); 877 878 if (uiop->uio_loffset >= MAXOFF_T) { 879 if (eofp) 880 *eofp = 1; 881 return (0); 882 } 883 884 if (uiop->uio_iovcnt != 1) 885 return (EINVAL); 886 887 if (dvp->v_type != VDIR) 888 return (ENOTDIR); 889 890 /* Load the initial contents */ 891 if (ddv->dv_flags & DV_BUILD) { 892 if (!rw_tryupgrade(&ddv->dv_contents)) { 893 rw_exit(&ddv->dv_contents); 894 rw_enter(&ddv->dv_contents, RW_WRITER); 895 } 896 897 /* recheck and fill */ 898 if (ddv->dv_flags & DV_BUILD) 899 dv_filldir(ddv); 900 901 rw_downgrade(&ddv->dv_contents); 902 } 903 904 soff = uiop->uio_loffset; 905 bufsz = uiop->uio_iov->iov_len; 906 de = bufp = kmem_alloc(bufsz, KM_SLEEP); 907 movesz = 0; 908 dv = (struct dv_node *)-1; 909 910 /* 911 * Move as many entries into the uio structure as it will take. 912 * Special case "." and "..". 913 */ 914 diroff = 0; 915 if (soff == 0) { /* . */ 916 reclen = DIRENT64_RECLEN(strlen(".")); 917 if ((movesz + reclen) > bufsz) 918 goto full; 919 de->d_ino = (ino64_t)ddv->dv_ino; 920 de->d_off = (off64_t)diroff + 1; 921 de->d_reclen = (ushort_t)reclen; 922 923 /* use strncpy(9f) to zero out uninitialized bytes */ 924 925 (void) strncpy(de->d_name, ".", DIRENT64_NAMELEN(reclen)); 926 movesz += reclen; 927 de = (dirent64_t *)(intptr_t)((char *)de + reclen); 928 dcmn_err3(("devfs_readdir: A: diroff %lld, soff %lld: '%s' " 929 "reclen %lu\n", diroff, soff, ".", reclen)); 930 } 931 932 diroff++; 933 if (soff <= 1) { /* .. */ 934 reclen = DIRENT64_RECLEN(strlen("..")); 935 if ((movesz + reclen) > bufsz) 936 goto full; 937 de->d_ino = (ino64_t)ddv->dv_dotdot->dv_ino; 938 de->d_off = (off64_t)diroff + 1; 939 de->d_reclen = (ushort_t)reclen; 940 941 /* use strncpy(9f) to zero out uninitialized bytes */ 942 943 (void) strncpy(de->d_name, "..", DIRENT64_NAMELEN(reclen)); 944 movesz += reclen; 945 de = (dirent64_t *)(intptr_t)((char *)de + reclen); 946 dcmn_err3(("devfs_readdir: B: diroff %lld, soff %lld: '%s' " 947 "reclen %lu\n", diroff, soff, "..", reclen)); 948 } 949 950 diroff++; 951 for (dv = ddv->dv_dot; dv; dv = dv->dv_next, diroff++) { 952 /* 953 * although DDM_INTERNAL_PATH minor nodes are skipped for 954 * readdirs outside the kernel, they still occupy directory 955 * offsets 956 */ 957 if (diroff < soff || 958 ((dv->dv_flags & DV_INTERNAL) && (cred != kcred))) 959 continue; 960 961 reclen = DIRENT64_RECLEN(strlen(dv->dv_name)); 962 if ((movesz + reclen) > bufsz) { 963 dcmn_err3(("devfs_readdir: C: diroff " 964 "%lld, soff %lld: '%s' reclen %lu\n", 965 diroff, soff, dv->dv_name, reclen)); 966 goto full; 967 } 968 de->d_ino = (ino64_t)dv->dv_ino; 969 de->d_off = (off64_t)diroff + 1; 970 de->d_reclen = (ushort_t)reclen; 971 972 /* use strncpy(9f) to zero out uninitialized bytes */ 973 974 ASSERT(strlen(dv->dv_name) + 1 <= 975 DIRENT64_NAMELEN(reclen)); 976 (void) strncpy(de->d_name, dv->dv_name, 977 DIRENT64_NAMELEN(reclen)); 978 979 movesz += reclen; 980 de = (dirent64_t *)(intptr_t)((char *)de + reclen); 981 dcmn_err4(("devfs_readdir: D: diroff " 982 "%lld, soff %lld: '%s' reclen %lu\n", diroff, soff, 983 dv->dv_name, reclen)); 984 } 985 986 /* the buffer is full, or we exhausted everything */ 987 full: dcmn_err3(("devfs_readdir: moving %lu bytes: " 988 "diroff %lld, soff %lld, dv %p\n", 989 movesz, diroff, soff, (void *)dv)); 990 991 if ((movesz == 0) && dv) 992 error = EINVAL; /* cannot be represented */ 993 else { 994 error = uiomove(bufp, movesz, UIO_READ, uiop); 995 if (error == 0) { 996 if (eofp) 997 *eofp = dv ? 0 : 1; 998 uiop->uio_loffset = diroff; 999 } 1000 1001 va.va_mask = AT_ATIME; 1002 gethrestime(&va.va_atime); 1003 rw_exit(&ddv->dv_contents); 1004 (void) devfs_setattr(dvp, &va, 0, cred, ct); 1005 rw_enter(&ddv->dv_contents, RW_READER); 1006 } 1007 1008 kmem_free(bufp, bufsz); 1009 return (error); 1010 } 1011 1012 /*ARGSUSED*/ 1013 static int 1014 devfs_fsync(struct vnode *vp, int syncflag, struct cred *cred, 1015 caller_context_t *ct) 1016 { 1017 /* 1018 * Message goes to console only. Otherwise, the message 1019 * causes devfs_fsync to be invoked again... infinite loop 1020 */ 1021 dcmn_err2(("devfs_fsync %s\n", VTODV(vp)->dv_name)); 1022 return (0); 1023 } 1024 1025 /* 1026 * Normally, we leave the dv_node here at count of 0. 1027 * The node will be destroyed when dv_cleandir() is called. 1028 * 1029 * Stale dv_node's are already unlinked from the fs tree, 1030 * so dv_cleandir() won't find them. We destroy such nodes 1031 * immediately. 1032 */ 1033 /*ARGSUSED1*/ 1034 static void 1035 devfs_inactive(struct vnode *vp, struct cred *cred, caller_context_t *ct) 1036 { 1037 int destroy; 1038 struct dv_node *dv = VTODV(vp); 1039 1040 dcmn_err2(("devfs_inactive: %s\n", dv->dv_name)); 1041 mutex_enter(&vp->v_lock); 1042 ASSERT(vp->v_count >= 1); 1043 --vp->v_count; 1044 destroy = (DV_STALE(dv) && vp->v_count == 0); 1045 mutex_exit(&vp->v_lock); 1046 1047 /* stale nodes cannot be rediscovered, destroy it here */ 1048 if (destroy) 1049 dv_destroy(dv, 0); 1050 } 1051 1052 /* 1053 * XXX Why do we need this? NFS mounted /dev directories? 1054 * XXX Talk to peter staubach about this. 1055 */ 1056 /*ARGSUSED2*/ 1057 static int 1058 devfs_fid(struct vnode *vp, struct fid *fidp, caller_context_t *ct) 1059 { 1060 struct dv_node *dv = VTODV(vp); 1061 struct dv_fid *dv_fid; 1062 1063 if (fidp->fid_len < (sizeof (struct dv_fid) - sizeof (ushort_t))) { 1064 fidp->fid_len = sizeof (struct dv_fid) - sizeof (ushort_t); 1065 return (ENOSPC); 1066 } 1067 1068 dv_fid = (struct dv_fid *)fidp; 1069 bzero(dv_fid, sizeof (struct dv_fid)); 1070 dv_fid->dvfid_len = (int)sizeof (struct dv_fid) - sizeof (ushort_t); 1071 dv_fid->dvfid_ino = dv->dv_ino; 1072 /* dv_fid->dvfid_gen = dv->tn_gen; XXX ? */ 1073 1074 return (0); 1075 } 1076 1077 /* 1078 * This pair of routines bracket all VOP_READ, VOP_WRITE 1079 * and VOP_READDIR requests. The contents lock stops things 1080 * moving around while we're looking at them. 1081 * 1082 * Also used by file and record locking. 1083 */ 1084 /*ARGSUSED2*/ 1085 static int 1086 devfs_rwlock(struct vnode *vp, int write_flag, caller_context_t *ct) 1087 { 1088 dcmn_err2(("devfs_rwlock %s\n", VTODV(vp)->dv_name)); 1089 rw_enter(&VTODV(vp)->dv_contents, write_flag ? RW_WRITER : RW_READER); 1090 return (write_flag); 1091 } 1092 1093 /*ARGSUSED1*/ 1094 static void 1095 devfs_rwunlock(struct vnode *vp, int write_flag, caller_context_t *ct) 1096 { 1097 dcmn_err2(("devfs_rwunlock %s\n", VTODV(vp)->dv_name)); 1098 rw_exit(&VTODV(vp)->dv_contents); 1099 } 1100 1101 /* 1102 * XXX Should probably do a better job of computing the maximum 1103 * offset available in the directory. 1104 */ 1105 /*ARGSUSED1*/ 1106 static int 1107 devfs_seek(struct vnode *vp, offset_t ooff, offset_t *noffp, 1108 caller_context_t *ct) 1109 { 1110 ASSERT(vp->v_type == VDIR); 1111 dcmn_err2(("devfs_seek %s\n", VTODV(vp)->dv_name)); 1112 return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0); 1113 } 1114 1115 vnodeops_t *dv_vnodeops; 1116 1117 const fs_operation_def_t dv_vnodeops_template[] = { 1118 VOPNAME_OPEN, { .vop_open = devfs_open }, 1119 VOPNAME_CLOSE, { .vop_close = devfs_close }, 1120 VOPNAME_READ, { .vop_read = devfs_read }, 1121 VOPNAME_WRITE, { .vop_write = devfs_write }, 1122 VOPNAME_IOCTL, { .vop_ioctl = devfs_ioctl }, 1123 VOPNAME_GETATTR, { .vop_getattr = devfs_getattr }, 1124 VOPNAME_SETATTR, { .vop_setattr = devfs_setattr }, 1125 VOPNAME_ACCESS, { .vop_access = devfs_access }, 1126 VOPNAME_LOOKUP, { .vop_lookup = devfs_lookup }, 1127 VOPNAME_CREATE, { .vop_create = devfs_create }, 1128 VOPNAME_READDIR, { .vop_readdir = devfs_readdir }, 1129 VOPNAME_FSYNC, { .vop_fsync = devfs_fsync }, 1130 VOPNAME_INACTIVE, { .vop_inactive = devfs_inactive }, 1131 VOPNAME_FID, { .vop_fid = devfs_fid }, 1132 VOPNAME_RWLOCK, { .vop_rwlock = devfs_rwlock }, 1133 VOPNAME_RWUNLOCK, { .vop_rwunlock = devfs_rwunlock }, 1134 VOPNAME_SEEK, { .vop_seek = devfs_seek }, 1135 VOPNAME_PATHCONF, { .vop_pathconf = devfs_pathconf }, 1136 VOPNAME_DISPOSE, { .error = fs_error }, 1137 VOPNAME_SETSECATTR, { .vop_setsecattr = devfs_setsecattr }, 1138 VOPNAME_GETSECATTR, { .vop_getsecattr = devfs_getsecattr }, 1139 NULL, NULL 1140 }; 1141