ptyfs_vnops.c revision 1.53
1 /* $NetBSD: ptyfs_vnops.c,v 1.53 2017/04/11 14:24:59 riastradh Exp $ */ 2 3 /* 4 * Copyright (c) 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95 35 */ 36 37 /* 38 * Copyright (c) 1993 Jan-Simon Pendry 39 * 40 * This code is derived from software contributed to Berkeley by 41 * Jan-Simon Pendry. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by the University of 54 * California, Berkeley and its contributors. 55 * 4. Neither the name of the University nor the names of its contributors 56 * may be used to endorse or promote products derived from this software 57 * without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95 72 */ 73 74 /* 75 * ptyfs vnode interface 76 */ 77 78 #include <sys/cdefs.h> 79 __KERNEL_RCSID(0, "$NetBSD: ptyfs_vnops.c,v 1.53 2017/04/11 14:24:59 riastradh Exp $"); 80 81 #include <sys/param.h> 82 #include <sys/systm.h> 83 #include <sys/time.h> 84 #include <sys/kernel.h> 85 #include <sys/file.h> 86 #include <sys/filedesc.h> 87 #include <sys/proc.h> 88 #include <sys/vnode.h> 89 #include <sys/namei.h> 90 #include <sys/malloc.h> 91 #include <sys/mount.h> 92 #include <sys/select.h> 93 #include <sys/dirent.h> 94 #include <sys/resourcevar.h> 95 #include <sys/stat.h> 96 #include <sys/conf.h> 97 #include <sys/tty.h> 98 #include <sys/pty.h> 99 #include <sys/kauth.h> 100 101 #include <uvm/uvm_extern.h> /* for PAGE_SIZE */ 102 103 #include <machine/reg.h> 104 105 #include <fs/ptyfs/ptyfs.h> 106 #include <miscfs/genfs/genfs.h> 107 #include <miscfs/specfs/specdev.h> 108 109 MALLOC_DECLARE(M_PTYFSTMP); 110 111 /* 112 * Vnode Operations. 113 * 114 */ 115 116 int ptyfs_lookup (void *); 117 #define ptyfs_create genfs_eopnotsupp 118 #define ptyfs_mknod genfs_eopnotsupp 119 int ptyfs_open (void *); 120 int ptyfs_close (void *); 121 int ptyfs_access (void *); 122 int ptyfs_getattr (void *); 123 int ptyfs_setattr (void *); 124 int ptyfs_read (void *); 125 int ptyfs_write (void *); 126 #define ptyfs_fcntl genfs_fcntl 127 int ptyfs_ioctl (void *); 128 int ptyfs_poll (void *); 129 int ptyfs_kqfilter (void *); 130 #define ptyfs_revoke genfs_revoke 131 #define ptyfs_mmap genfs_eopnotsupp 132 #define ptyfs_fsync genfs_nullop 133 #define ptyfs_seek genfs_nullop 134 #define ptyfs_remove genfs_eopnotsupp 135 #define ptyfs_link genfs_abortop 136 #define ptyfs_rename genfs_eopnotsupp 137 #define ptyfs_mkdir genfs_eopnotsupp 138 #define ptyfs_rmdir genfs_eopnotsupp 139 #define ptyfs_symlink genfs_abortop 140 int ptyfs_readdir (void *); 141 #define ptyfs_readlink genfs_eopnotsupp 142 #define ptyfs_abortop genfs_abortop 143 int ptyfs_reclaim (void *); 144 int ptyfs_inactive (void *); 145 #define ptyfs_lock genfs_lock 146 #define ptyfs_unlock genfs_unlock 147 #define ptyfs_bmap genfs_badop 148 #define ptyfs_strategy genfs_badop 149 int ptyfs_print (void *); 150 int ptyfs_pathconf (void *); 151 #define ptyfs_islocked genfs_islocked 152 int ptyfs_advlock (void *); 153 #define ptyfs_bwrite genfs_eopnotsupp 154 #define ptyfs_putpages genfs_null_putpages 155 156 static int ptyfs_update(struct vnode *, const struct timespec *, 157 const struct timespec *, int); 158 static int ptyfs_chown(struct vnode *, uid_t, gid_t, kauth_cred_t, 159 struct lwp *); 160 static int ptyfs_chmod(struct vnode *, mode_t, kauth_cred_t, struct lwp *); 161 static int atoi(const char *, size_t); 162 163 /* 164 * ptyfs vnode operations. 165 */ 166 int (**ptyfs_vnodeop_p)(void *); 167 const struct vnodeopv_entry_desc ptyfs_vnodeop_entries[] = { 168 { &vop_default_desc, vn_default_error }, 169 { &vop_lookup_desc, ptyfs_lookup }, /* lookup */ 170 { &vop_create_desc, ptyfs_create }, /* create */ 171 { &vop_mknod_desc, ptyfs_mknod }, /* mknod */ 172 { &vop_open_desc, ptyfs_open }, /* open */ 173 { &vop_close_desc, ptyfs_close }, /* close */ 174 { &vop_access_desc, ptyfs_access }, /* access */ 175 { &vop_getattr_desc, ptyfs_getattr }, /* getattr */ 176 { &vop_setattr_desc, ptyfs_setattr }, /* setattr */ 177 { &vop_read_desc, ptyfs_read }, /* read */ 178 { &vop_write_desc, ptyfs_write }, /* write */ 179 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */ 180 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */ 181 { &vop_ioctl_desc, ptyfs_ioctl }, /* ioctl */ 182 { &vop_fcntl_desc, ptyfs_fcntl }, /* fcntl */ 183 { &vop_poll_desc, ptyfs_poll }, /* poll */ 184 { &vop_kqfilter_desc, ptyfs_kqfilter }, /* kqfilter */ 185 { &vop_revoke_desc, ptyfs_revoke }, /* revoke */ 186 { &vop_mmap_desc, ptyfs_mmap }, /* mmap */ 187 { &vop_fsync_desc, ptyfs_fsync }, /* fsync */ 188 { &vop_seek_desc, ptyfs_seek }, /* seek */ 189 { &vop_remove_desc, ptyfs_remove }, /* remove */ 190 { &vop_link_desc, ptyfs_link }, /* link */ 191 { &vop_rename_desc, ptyfs_rename }, /* rename */ 192 { &vop_mkdir_desc, ptyfs_mkdir }, /* mkdir */ 193 { &vop_rmdir_desc, ptyfs_rmdir }, /* rmdir */ 194 { &vop_symlink_desc, ptyfs_symlink }, /* symlink */ 195 { &vop_readdir_desc, ptyfs_readdir }, /* readdir */ 196 { &vop_readlink_desc, ptyfs_readlink }, /* readlink */ 197 { &vop_abortop_desc, ptyfs_abortop }, /* abortop */ 198 { &vop_inactive_desc, ptyfs_inactive }, /* inactive */ 199 { &vop_reclaim_desc, ptyfs_reclaim }, /* reclaim */ 200 { &vop_lock_desc, ptyfs_lock }, /* lock */ 201 { &vop_unlock_desc, ptyfs_unlock }, /* unlock */ 202 { &vop_bmap_desc, ptyfs_bmap }, /* bmap */ 203 { &vop_strategy_desc, ptyfs_strategy }, /* strategy */ 204 { &vop_print_desc, ptyfs_print }, /* print */ 205 { &vop_islocked_desc, ptyfs_islocked }, /* islocked */ 206 { &vop_pathconf_desc, ptyfs_pathconf }, /* pathconf */ 207 { &vop_advlock_desc, ptyfs_advlock }, /* advlock */ 208 { &vop_bwrite_desc, ptyfs_bwrite }, /* bwrite */ 209 { &vop_putpages_desc, ptyfs_putpages }, /* putpages */ 210 { NULL, NULL } 211 }; 212 const struct vnodeopv_desc ptyfs_vnodeop_opv_desc = 213 { &ptyfs_vnodeop_p, ptyfs_vnodeop_entries }; 214 215 /* 216 * free any private data and remove the node 217 * from any private lists. 218 */ 219 int 220 ptyfs_reclaim(void *v) 221 { 222 struct vop_reclaim_args /* { 223 struct vnode *a_vp; 224 } */ *ap = v; 225 struct vnode *vp = ap->a_vp; 226 227 vp->v_data = NULL; 228 return 0; 229 } 230 231 int 232 ptyfs_inactive(void *v) 233 { 234 struct vop_inactive_v2_args /* { 235 struct vnode *a_vp; 236 bool *a_recycle; 237 } */ *ap = v; 238 struct vnode *vp = ap->a_vp; 239 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 240 241 if (ptyfs->ptyfs_type == PTYFSptc) 242 ptyfs_clr_active(vp->v_mount, ptyfs->ptyfs_pty); 243 244 return 0; 245 } 246 247 /* 248 * Return POSIX pathconf information applicable to special devices. 249 */ 250 int 251 ptyfs_pathconf(void *v) 252 { 253 struct vop_pathconf_args /* { 254 struct vnode *a_vp; 255 int a_name; 256 register_t *a_retval; 257 } */ *ap = v; 258 259 switch (ap->a_name) { 260 case _PC_LINK_MAX: 261 *ap->a_retval = LINK_MAX; 262 return 0; 263 case _PC_MAX_CANON: 264 *ap->a_retval = MAX_CANON; 265 return 0; 266 case _PC_MAX_INPUT: 267 *ap->a_retval = MAX_INPUT; 268 return 0; 269 case _PC_PIPE_BUF: 270 *ap->a_retval = PIPE_BUF; 271 return 0; 272 case _PC_CHOWN_RESTRICTED: 273 *ap->a_retval = 1; 274 return 0; 275 case _PC_VDISABLE: 276 *ap->a_retval = _POSIX_VDISABLE; 277 return 0; 278 case _PC_SYNC_IO: 279 *ap->a_retval = 1; 280 return 0; 281 default: 282 return EINVAL; 283 } 284 } 285 286 /* 287 * _print is used for debugging. 288 * just print a readable description 289 * of (vp). 290 */ 291 int 292 ptyfs_print(void *v) 293 { 294 struct vop_print_args /* { 295 struct vnode *a_vp; 296 } */ *ap = v; 297 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 298 299 printf("tag VT_PTYFS, type %d, pty %d\n", 300 ptyfs->ptyfs_type, ptyfs->ptyfs_pty); 301 return 0; 302 } 303 304 /* 305 * support advisory locking on pty nodes 306 */ 307 int 308 ptyfs_advlock(void *v) 309 { 310 struct vop_print_args /* { 311 struct vnode *a_vp; 312 } */ *ap = v; 313 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 314 315 switch (ptyfs->ptyfs_type) { 316 case PTYFSpts: 317 case PTYFSptc: 318 return spec_advlock(v); 319 default: 320 return EOPNOTSUPP; 321 } 322 } 323 324 /* 325 * Invent attributes for ptyfsnode (vp) and store 326 * them in (vap). 327 * Directories lengths are returned as zero since 328 * any real length would require the genuine size 329 * to be computed, and nothing cares anyway. 330 * 331 * this is relatively minimal for ptyfs. 332 */ 333 int 334 ptyfs_getattr(void *v) 335 { 336 struct vop_getattr_args /* { 337 struct vnode *a_vp; 338 struct vattr *a_vap; 339 kauth_cred_t a_cred; 340 } */ *ap = v; 341 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 342 struct vattr *vap = ap->a_vap; 343 344 PTYFS_ITIMES(ptyfs, NULL, NULL, NULL); 345 346 /* start by zeroing out the attributes */ 347 vattr_null(vap); 348 349 /* next do all the common fields */ 350 vap->va_type = ap->a_vp->v_type; 351 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0]; 352 vap->va_fileid = ptyfs->ptyfs_fileno; 353 vap->va_gen = 0; 354 vap->va_flags = 0; 355 vap->va_blocksize = PAGE_SIZE; 356 357 vap->va_atime = ptyfs->ptyfs_atime; 358 vap->va_mtime = ptyfs->ptyfs_mtime; 359 vap->va_ctime = ptyfs->ptyfs_ctime; 360 vap->va_birthtime = ptyfs->ptyfs_birthtime; 361 vap->va_mode = ptyfs->ptyfs_mode; 362 vap->va_flags = ptyfs->ptyfs_flags; 363 vap->va_uid = ptyfs->ptyfs_uid; 364 vap->va_gid = ptyfs->ptyfs_gid; 365 366 switch (ptyfs->ptyfs_type) { 367 case PTYFSpts: 368 case PTYFSptc: 369 if (pty_isfree(ptyfs->ptyfs_pty, 1)) 370 return ENOENT; 371 vap->va_bytes = vap->va_size = 0; 372 vap->va_rdev = ap->a_vp->v_rdev; 373 vap->va_nlink = 1; 374 break; 375 case PTYFSroot: 376 vap->va_rdev = 0; 377 vap->va_bytes = vap->va_size = DEV_BSIZE; 378 vap->va_nlink = 2; 379 break; 380 default: 381 return EOPNOTSUPP; 382 } 383 384 return 0; 385 } 386 387 /*ARGSUSED*/ 388 int 389 ptyfs_setattr(void *v) 390 { 391 struct vop_setattr_args /* { 392 struct vnodeop_desc *a_desc; 393 struct vnode *a_vp; 394 struct vattr *a_vap; 395 kauth_cred_t a_cred; 396 } */ *ap = v; 397 struct vnode *vp = ap->a_vp; 398 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 399 struct vattr *vap = ap->a_vap; 400 kauth_cred_t cred = ap->a_cred; 401 struct lwp *l = curlwp; 402 int error; 403 kauth_action_t action = KAUTH_VNODE_WRITE_FLAGS; 404 bool changing_sysflags = false; 405 406 if (vap->va_size != VNOVAL) { 407 switch (ptyfs->ptyfs_type) { 408 case PTYFSroot: 409 return EISDIR; 410 case PTYFSpts: 411 case PTYFSptc: 412 break; 413 default: 414 return EINVAL; 415 } 416 } 417 418 if (vap->va_flags != VNOVAL) { 419 if (vp->v_mount->mnt_flag & MNT_RDONLY) 420 return EROFS; 421 422 /* Immutable and append-only flags are not supported on ptyfs. */ 423 if (vap->va_flags & (IMMUTABLE | APPEND)) 424 return EINVAL; 425 426 /* Snapshot flag cannot be set or cleared */ 427 if ((vap->va_flags & SF_SNAPSHOT) != (ptyfs->ptyfs_flags & SF_SNAPSHOT)) 428 return EPERM; 429 430 if ((ptyfs->ptyfs_flags & SF_SETTABLE) != (vap->va_flags & SF_SETTABLE)) { 431 changing_sysflags = true; 432 action |= KAUTH_VNODE_WRITE_SYSFLAGS; 433 } 434 435 error = kauth_authorize_vnode(cred, action, vp, NULL, 436 genfs_can_chflags(cred, vp->v_type, ptyfs->ptyfs_uid, 437 changing_sysflags)); 438 if (error) 439 return error; 440 441 if (changing_sysflags) { 442 ptyfs->ptyfs_flags = vap->va_flags; 443 } else { 444 ptyfs->ptyfs_flags &= SF_SETTABLE; 445 ptyfs->ptyfs_flags |= (vap->va_flags & UF_SETTABLE); 446 } 447 ptyfs->ptyfs_status |= PTYFS_CHANGE; 448 } 449 450 /* 451 * Go through the fields and update iff not VNOVAL. 452 */ 453 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { 454 if (vp->v_mount->mnt_flag & MNT_RDONLY) 455 return EROFS; 456 if (ptyfs->ptyfs_type == PTYFSroot) 457 return EPERM; 458 error = ptyfs_chown(vp, vap->va_uid, vap->va_gid, cred, l); 459 if (error) 460 return error; 461 } 462 463 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL || 464 vap->va_birthtime.tv_sec != VNOVAL) { 465 if (vp->v_mount->mnt_flag & MNT_RDONLY) 466 return EROFS; 467 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0) 468 return EPERM; 469 error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_TIMES, vp, 470 NULL, genfs_can_chtimes(vp, vap->va_vaflags, 471 ptyfs->ptyfs_uid, cred)); 472 if (error) 473 return (error); 474 if (vap->va_atime.tv_sec != VNOVAL) 475 if (!(vp->v_mount->mnt_flag & MNT_NOATIME)) 476 ptyfs->ptyfs_status |= PTYFS_ACCESS; 477 if (vap->va_mtime.tv_sec != VNOVAL) { 478 ptyfs->ptyfs_status |= PTYFS_CHANGE | PTYFS_MODIFY; 479 if (vp->v_mount->mnt_flag & MNT_RELATIME) 480 ptyfs->ptyfs_status |= PTYFS_ACCESS; 481 } 482 if (vap->va_birthtime.tv_sec != VNOVAL) 483 ptyfs->ptyfs_birthtime = vap->va_birthtime; 484 ptyfs->ptyfs_status |= PTYFS_CHANGE; 485 error = ptyfs_update(vp, &vap->va_atime, &vap->va_mtime, 0); 486 if (error) 487 return error; 488 } 489 if (vap->va_mode != (mode_t)VNOVAL) { 490 if (vp->v_mount->mnt_flag & MNT_RDONLY) 491 return EROFS; 492 if (ptyfs->ptyfs_type == PTYFSroot) 493 return EPERM; 494 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0 && 495 (vap->va_mode & 496 (S_IXUSR|S_IWUSR|S_IXGRP|S_IWGRP|S_IXOTH|S_IWOTH))) 497 return EPERM; 498 error = ptyfs_chmod(vp, vap->va_mode, cred, l); 499 if (error) 500 return error; 501 } 502 VN_KNOTE(vp, NOTE_ATTRIB); 503 return 0; 504 } 505 506 /* 507 * Change the mode on a file. 508 * Inode must be locked before calling. 509 */ 510 static int 511 ptyfs_chmod(struct vnode *vp, mode_t mode, kauth_cred_t cred, struct lwp *l) 512 { 513 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 514 int error; 515 516 error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_SECURITY, vp, 517 NULL, genfs_can_chmod(vp->v_type, cred, ptyfs->ptyfs_uid, 518 ptyfs->ptyfs_gid, mode)); 519 if (error) 520 return (error); 521 522 ptyfs->ptyfs_mode &= ~ALLPERMS; 523 ptyfs->ptyfs_mode |= (mode & ALLPERMS); 524 return 0; 525 } 526 527 /* 528 * Perform chown operation on inode ip; 529 * inode must be locked prior to call. 530 */ 531 static int 532 ptyfs_chown(struct vnode *vp, uid_t uid, gid_t gid, kauth_cred_t cred, 533 struct lwp *l) 534 { 535 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 536 int error; 537 538 if (uid == (uid_t)VNOVAL) 539 uid = ptyfs->ptyfs_uid; 540 if (gid == (gid_t)VNOVAL) 541 gid = ptyfs->ptyfs_gid; 542 543 error = kauth_authorize_vnode(cred, KAUTH_VNODE_CHANGE_OWNERSHIP, vp, 544 NULL, genfs_can_chown(cred, ptyfs->ptyfs_uid, ptyfs->ptyfs_gid, 545 uid, gid)); 546 if (error) 547 return (error); 548 549 ptyfs->ptyfs_gid = gid; 550 ptyfs->ptyfs_uid = uid; 551 return 0; 552 } 553 554 /* 555 * implement access checking. 556 * 557 * actually, the check for super-user is slightly 558 * broken since it will allow read access to write-only 559 * objects. this doesn't cause any particular trouble 560 * but does mean that the i/o entry points need to check 561 * that the operation really does make sense. 562 */ 563 int 564 ptyfs_access(void *v) 565 { 566 struct vop_access_args /* { 567 struct vnode *a_vp; 568 int a_mode; 569 kauth_cred_t a_cred; 570 } */ *ap = v; 571 struct vattr va; 572 int error; 573 574 if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred)) != 0) 575 return error; 576 577 return kauth_authorize_vnode(ap->a_cred, 578 KAUTH_ACCESS_ACTION(ap->a_mode, ap->a_vp->v_type, va.va_mode), 579 ap->a_vp, NULL, genfs_can_access(va.va_type, va.va_mode, va.va_uid, 580 va.va_gid, ap->a_mode, ap->a_cred)); 581 } 582 583 /* 584 * lookup. this is incredibly complicated in the 585 * general case, however for most pseudo-filesystems 586 * very little needs to be done. 587 * 588 * Locking isn't hard here, just poorly documented. 589 * 590 * If we're looking up ".", just vref the parent & return it. 591 * 592 * If we're looking up "..", unlock the parent, and lock "..". If everything 593 * went ok, try to re-lock the parent. We do this to prevent lock races. 594 * 595 * For anything else, get the needed node. 596 * 597 * We try to exit with the parent locked in error cases. 598 */ 599 int 600 ptyfs_lookup(void *v) 601 { 602 struct vop_lookup_v2_args /* { 603 struct vnode * a_dvp; 604 struct vnode ** a_vpp; 605 struct componentname * a_cnp; 606 } */ *ap = v; 607 struct componentname *cnp = ap->a_cnp; 608 struct vnode **vpp = ap->a_vpp; 609 struct vnode *dvp = ap->a_dvp; 610 const char *pname = cnp->cn_nameptr; 611 struct ptyfsnode *ptyfs; 612 int pty, error; 613 614 *vpp = NULL; 615 616 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 617 return EROFS; 618 619 if (cnp->cn_namelen == 1 && *pname == '.') { 620 *vpp = dvp; 621 vref(dvp); 622 return 0; 623 } 624 625 ptyfs = VTOPTYFS(dvp); 626 switch (ptyfs->ptyfs_type) { 627 case PTYFSroot: 628 /* 629 * Shouldn't get here with .. in the root node. 630 */ 631 if (cnp->cn_flags & ISDOTDOT) 632 return EIO; 633 634 pty = atoi(pname, cnp->cn_namelen); 635 if (pty < 0 || ptyfs_next_active(dvp->v_mount, pty) != pty) 636 break; 637 error = ptyfs_allocvp(dvp->v_mount, vpp, PTYFSpts, pty); 638 if (error) 639 return error; 640 if (ptyfs_next_active(dvp->v_mount, pty) != pty) { 641 vrele(*vpp); 642 *vpp = NULL; 643 return ENOENT; 644 } 645 return 0; 646 647 default: 648 return ENOTDIR; 649 } 650 651 return cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS; 652 } 653 654 /* 655 * readdir returns directory entries from ptyfsnode (vp). 656 * 657 * the strategy here with ptyfs is to generate a single 658 * directory entry at a time (struct dirent) and then 659 * copy that out to userland using uiomove. a more efficent 660 * though more complex implementation, would try to minimize 661 * the number of calls to uiomove(). for ptyfs, this is 662 * hardly worth the added code complexity. 663 * 664 * this should just be done through read() 665 */ 666 int 667 ptyfs_readdir(void *v) 668 { 669 struct vop_readdir_args /* { 670 struct vnode *a_vp; 671 struct uio *a_uio; 672 kauth_cred_t a_cred; 673 int *a_eofflag; 674 off_t **a_cookies; 675 int *a_ncookies; 676 } */ *ap = v; 677 struct uio *uio = ap->a_uio; 678 struct dirent *dp; 679 struct ptyfsnode *ptyfs; 680 off_t i; 681 int error; 682 off_t *cookies = NULL; 683 int ncookies; 684 struct vnode *vp; 685 int n, nc = 0; 686 687 vp = ap->a_vp; 688 ptyfs = VTOPTYFS(vp); 689 690 if (uio->uio_resid < UIO_MX) 691 return EINVAL; 692 if (uio->uio_offset < 0) 693 return EINVAL; 694 695 dp = malloc(sizeof(struct dirent), M_PTYFSTMP, M_WAITOK | M_ZERO); 696 697 error = 0; 698 i = uio->uio_offset; 699 dp->d_reclen = UIO_MX; 700 ncookies = uio->uio_resid / UIO_MX; 701 702 if (ptyfs->ptyfs_type != PTYFSroot) { 703 error = ENOTDIR; 704 goto out; 705 } 706 707 if (i >= npty) 708 goto out; 709 710 if (ap->a_ncookies) { 711 ncookies = min(ncookies, (npty + 2 - i)); 712 cookies = malloc(ncookies * sizeof (off_t), 713 M_TEMP, M_WAITOK); 714 *ap->a_cookies = cookies; 715 } 716 717 for (; i < 2; i++) { 718 /* `.' and/or `..' */ 719 dp->d_fileno = PTYFS_FILENO(0, PTYFSroot); 720 dp->d_namlen = i + 1; 721 (void)memcpy(dp->d_name, "..", dp->d_namlen); 722 dp->d_name[i + 1] = '\0'; 723 dp->d_type = DT_DIR; 724 if ((error = uiomove(dp, UIO_MX, uio)) != 0) 725 goto out; 726 if (cookies) 727 *cookies++ = i + 1; 728 nc++; 729 } 730 while (uio->uio_resid >= UIO_MX) { 731 /* check for used ptys */ 732 n = ptyfs_next_active(vp->v_mount, i - 2); 733 if (n < 0) 734 break; 735 dp->d_fileno = PTYFS_FILENO(n, PTYFSpts); 736 dp->d_namlen = snprintf(dp->d_name, sizeof(dp->d_name), 737 "%lld", (long long)(n)); 738 dp->d_type = DT_CHR; 739 if ((error = uiomove(dp, UIO_MX, uio)) != 0) 740 goto out; 741 i = n + 3; 742 if (cookies) 743 *cookies++ = i; 744 nc++; 745 } 746 747 out: 748 /* not pertinent in error cases */ 749 ncookies = nc; 750 751 if (ap->a_ncookies) { 752 if (error) { 753 if (cookies) 754 free(*ap->a_cookies, M_TEMP); 755 *ap->a_ncookies = 0; 756 *ap->a_cookies = NULL; 757 } else 758 *ap->a_ncookies = ncookies; 759 } 760 uio->uio_offset = i; 761 free(dp, M_PTYFSTMP); 762 return error; 763 } 764 765 int 766 ptyfs_open(void *v) 767 { 768 struct vop_open_args /* { 769 struct vnode *a_vp; 770 int a_mode; 771 kauth_cred_t a_cred; 772 } */ *ap = v; 773 struct vnode *vp = ap->a_vp; 774 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 775 776 switch (ptyfs->ptyfs_type) { 777 case PTYFSpts: 778 case PTYFSptc: 779 return spec_open(v); 780 case PTYFSroot: 781 return 0; 782 default: 783 return EINVAL; 784 } 785 } 786 787 int 788 ptyfs_close(void *v) 789 { 790 struct vop_close_args /* { 791 struct vnode *a_vp; 792 int a_fflag; 793 kauth_cred_t a_cred; 794 } */ *ap = v; 795 struct vnode *vp = ap->a_vp; 796 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 797 798 mutex_enter(vp->v_interlock); 799 if (vp->v_usecount > 1) 800 PTYFS_ITIMES(ptyfs, NULL, NULL, NULL); 801 mutex_exit(vp->v_interlock); 802 803 switch (ptyfs->ptyfs_type) { 804 case PTYFSpts: 805 case PTYFSptc: 806 return spec_close(v); 807 case PTYFSroot: 808 return 0; 809 default: 810 return EINVAL; 811 } 812 } 813 814 int 815 ptyfs_read(void *v) 816 { 817 struct vop_read_args /* { 818 struct vnode *a_vp; 819 struct uio *a_uio; 820 int a_ioflag; 821 kauth_cred_t a_cred; 822 } */ *ap = v; 823 struct timespec ts; 824 struct vnode *vp = ap->a_vp; 825 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 826 int error; 827 828 if (vp->v_type == VDIR) 829 return EISDIR; 830 831 ptyfs->ptyfs_status |= PTYFS_ACCESS; 832 /* hardclock() resolution is good enough for ptyfs */ 833 getnanotime(&ts); 834 (void)ptyfs_update(vp, &ts, &ts, 0); 835 836 switch (ptyfs->ptyfs_type) { 837 case PTYFSpts: 838 case PTYFSptc: 839 VOP_UNLOCK(vp); 840 error = cdev_read(vp->v_rdev, ap->a_uio, ap->a_ioflag); 841 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 842 return error; 843 default: 844 return EOPNOTSUPP; 845 } 846 } 847 848 int 849 ptyfs_write(void *v) 850 { 851 struct vop_write_args /* { 852 struct vnode *a_vp; 853 struct uio *a_uio; 854 int a_ioflag; 855 kauth_cred_t a_cred; 856 } */ *ap = v; 857 struct timespec ts; 858 struct vnode *vp = ap->a_vp; 859 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 860 int error; 861 862 ptyfs->ptyfs_status |= PTYFS_MODIFY; 863 getnanotime(&ts); 864 (void)ptyfs_update(vp, &ts, &ts, 0); 865 866 switch (ptyfs->ptyfs_type) { 867 case PTYFSpts: 868 case PTYFSptc: 869 VOP_UNLOCK(vp); 870 error = cdev_write(vp->v_rdev, ap->a_uio, ap->a_ioflag); 871 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 872 return error; 873 default: 874 return EOPNOTSUPP; 875 } 876 } 877 878 int 879 ptyfs_ioctl(void *v) 880 { 881 struct vop_ioctl_args /* { 882 struct vnode *a_vp; 883 u_long a_command; 884 void *a_data; 885 int a_fflag; 886 kauth_cred_t a_cred; 887 } */ *ap = v; 888 struct vnode *vp = ap->a_vp; 889 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 890 891 switch (ptyfs->ptyfs_type) { 892 case PTYFSpts: 893 case PTYFSptc: 894 return cdev_ioctl(vp->v_rdev, ap->a_command, 895 ap->a_data, ap->a_fflag, curlwp); 896 default: 897 return EOPNOTSUPP; 898 } 899 } 900 901 int 902 ptyfs_poll(void *v) 903 { 904 struct vop_poll_args /* { 905 struct vnode *a_vp; 906 int a_events; 907 } */ *ap = v; 908 struct vnode *vp = ap->a_vp; 909 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 910 911 switch (ptyfs->ptyfs_type) { 912 case PTYFSpts: 913 case PTYFSptc: 914 return cdev_poll(vp->v_rdev, ap->a_events, curlwp); 915 default: 916 return genfs_poll(v); 917 } 918 } 919 920 int 921 ptyfs_kqfilter(void *v) 922 { 923 struct vop_kqfilter_args /* { 924 struct vnode *a_vp; 925 struct knote *a_kn; 926 } */ *ap = v; 927 struct vnode *vp = ap->a_vp; 928 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 929 930 switch (ptyfs->ptyfs_type) { 931 case PTYFSpts: 932 case PTYFSptc: 933 return cdev_kqfilter(vp->v_rdev, ap->a_kn); 934 default: 935 return genfs_kqfilter(v); 936 } 937 } 938 939 static int 940 ptyfs_update(struct vnode *vp, const struct timespec *acc, 941 const struct timespec *mod, int flags) 942 { 943 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 944 945 if (vp->v_mount->mnt_flag & MNT_RDONLY) 946 return 0; 947 948 PTYFS_ITIMES(ptyfs, acc, mod, NULL); 949 return 0; 950 } 951 952 void 953 ptyfs_itimes(struct ptyfsnode *ptyfs, const struct timespec *acc, 954 const struct timespec *mod, const struct timespec *cre) 955 { 956 struct timespec now; 957 958 KASSERT(ptyfs->ptyfs_status & (PTYFS_ACCESS|PTYFS_CHANGE|PTYFS_MODIFY)); 959 960 getnanotime(&now); 961 if (ptyfs->ptyfs_status & PTYFS_ACCESS) { 962 if (acc == NULL) 963 acc = &now; 964 ptyfs->ptyfs_atime = *acc; 965 } 966 if (ptyfs->ptyfs_status & PTYFS_MODIFY) { 967 if (mod == NULL) 968 mod = &now; 969 ptyfs->ptyfs_mtime = *mod; 970 } 971 if (ptyfs->ptyfs_status & PTYFS_CHANGE) { 972 if (cre == NULL) 973 cre = &now; 974 ptyfs->ptyfs_ctime = *cre; 975 } 976 ptyfs->ptyfs_status &= ~(PTYFS_ACCESS|PTYFS_CHANGE|PTYFS_MODIFY); 977 } 978 979 /* 980 * convert decimal ascii to int 981 */ 982 static int 983 atoi(const char *b, size_t len) 984 { 985 int p = 0; 986 987 while (len--) { 988 char c = *b++; 989 if (c < '0' || c > '9') 990 return -1; 991 p = 10 * p + (c - '0'); 992 } 993 994 return p; 995 } 996
Indexes created Mon Sep 29 21:09:56 GMT 2025