ptyfs_vnops.c revision 1.62
1 /* $NetBSD: ptyfs_vnops.c,v 1.62 2020/11/27 14:43:57 christos 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 1.62 2020/11/27 14:43:57 christos 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_accessx_desc, genfs_accessx }, /* accessx */ 176 { &vop_getattr_desc, ptyfs_getattr }, /* getattr */ 177 { &vop_setattr_desc, ptyfs_setattr }, /* setattr */ 178 { &vop_read_desc, ptyfs_read }, /* read */ 179 { &vop_write_desc, ptyfs_write }, /* write */ 180 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */ 181 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */ 182 { &vop_ioctl_desc, ptyfs_ioctl }, /* ioctl */ 183 { &vop_fcntl_desc, ptyfs_fcntl }, /* fcntl */ 184 { &vop_poll_desc, ptyfs_poll }, /* poll */ 185 { &vop_kqfilter_desc, ptyfs_kqfilter }, /* kqfilter */ 186 { &vop_revoke_desc, ptyfs_revoke }, /* revoke */ 187 { &vop_mmap_desc, ptyfs_mmap }, /* mmap */ 188 { &vop_fsync_desc, ptyfs_fsync }, /* fsync */ 189 { &vop_seek_desc, ptyfs_seek }, /* seek */ 190 { &vop_remove_desc, ptyfs_remove }, /* remove */ 191 { &vop_link_desc, ptyfs_link }, /* link */ 192 { &vop_rename_desc, ptyfs_rename }, /* rename */ 193 { &vop_mkdir_desc, ptyfs_mkdir }, /* mkdir */ 194 { &vop_rmdir_desc, ptyfs_rmdir }, /* rmdir */ 195 { &vop_symlink_desc, ptyfs_symlink }, /* symlink */ 196 { &vop_readdir_desc, ptyfs_readdir }, /* readdir */ 197 { &vop_readlink_desc, ptyfs_readlink }, /* readlink */ 198 { &vop_abortop_desc, ptyfs_abortop }, /* abortop */ 199 { &vop_inactive_desc, ptyfs_inactive }, /* inactive */ 200 { &vop_reclaim_desc, ptyfs_reclaim }, /* reclaim */ 201 { &vop_lock_desc, ptyfs_lock }, /* lock */ 202 { &vop_unlock_desc, ptyfs_unlock }, /* unlock */ 203 { &vop_bmap_desc, ptyfs_bmap }, /* bmap */ 204 { &vop_strategy_desc, ptyfs_strategy }, /* strategy */ 205 { &vop_print_desc, ptyfs_print }, /* print */ 206 { &vop_islocked_desc, ptyfs_islocked }, /* islocked */ 207 { &vop_pathconf_desc, ptyfs_pathconf }, /* pathconf */ 208 { &vop_advlock_desc, ptyfs_advlock }, /* advlock */ 209 { &vop_bwrite_desc, ptyfs_bwrite }, /* bwrite */ 210 { &vop_putpages_desc, ptyfs_putpages }, /* putpages */ 211 { NULL, NULL } 212 }; 213 const struct vnodeopv_desc ptyfs_vnodeop_opv_desc = 214 { &ptyfs_vnodeop_p, ptyfs_vnodeop_entries }; 215 216 /* 217 * free any private data and remove the node 218 * from any private lists. 219 */ 220 int 221 ptyfs_reclaim(void *v) 222 { 223 struct vop_reclaim_v2_args /* { 224 struct vnode *a_vp; 225 } */ *ap = v; 226 struct vnode *vp = ap->a_vp; 227 228 VOP_UNLOCK(vp); 229 230 vp->v_data = NULL; 231 return 0; 232 } 233 234 int 235 ptyfs_inactive(void *v) 236 { 237 struct vop_inactive_v2_args /* { 238 struct vnode *a_vp; 239 bool *a_recycle; 240 } */ *ap = v; 241 struct vnode *vp = ap->a_vp; 242 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 243 244 if (ptyfs->ptyfs_type == PTYFSptc) 245 ptyfs_clr_active(vp->v_mount, ptyfs->ptyfs_pty); 246 247 return 0; 248 } 249 250 /* 251 * Return POSIX pathconf information applicable to special devices. 252 */ 253 int 254 ptyfs_pathconf(void *v) 255 { 256 struct vop_pathconf_args /* { 257 struct vnode *a_vp; 258 int a_name; 259 register_t *a_retval; 260 } */ *ap = v; 261 262 switch (ap->a_name) { 263 case _PC_LINK_MAX: 264 *ap->a_retval = LINK_MAX; 265 return 0; 266 case _PC_MAX_CANON: 267 *ap->a_retval = MAX_CANON; 268 return 0; 269 case _PC_MAX_INPUT: 270 *ap->a_retval = MAX_INPUT; 271 return 0; 272 case _PC_PIPE_BUF: 273 *ap->a_retval = PIPE_BUF; 274 return 0; 275 case _PC_CHOWN_RESTRICTED: 276 *ap->a_retval = 1; 277 return 0; 278 case _PC_VDISABLE: 279 *ap->a_retval = _POSIX_VDISABLE; 280 return 0; 281 case _PC_SYNC_IO: 282 *ap->a_retval = 1; 283 return 0; 284 default: 285 return genfs_pathconf(ap); 286 } 287 } 288 289 /* 290 * _print is used for debugging. 291 * just print a readable description 292 * of (vp). 293 */ 294 int 295 ptyfs_print(void *v) 296 { 297 struct vop_print_args /* { 298 struct vnode *a_vp; 299 } */ *ap = v; 300 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 301 302 printf("tag VT_PTYFS, type %d, pty %d\n", 303 ptyfs->ptyfs_type, ptyfs->ptyfs_pty); 304 return 0; 305 } 306 307 /* 308 * support advisory locking on pty nodes 309 */ 310 int 311 ptyfs_advlock(void *v) 312 { 313 struct vop_print_args /* { 314 struct vnode *a_vp; 315 } */ *ap = v; 316 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 317 318 switch (ptyfs->ptyfs_type) { 319 case PTYFSpts: 320 case PTYFSptc: 321 return spec_advlock(v); 322 default: 323 return EOPNOTSUPP; 324 } 325 } 326 327 /* 328 * Invent attributes for ptyfsnode (vp) and store 329 * them in (vap). 330 * Directories lengths are returned as zero since 331 * any real length would require the genuine size 332 * to be computed, and nothing cares anyway. 333 * 334 * this is relatively minimal for ptyfs. 335 */ 336 int 337 ptyfs_getattr(void *v) 338 { 339 struct vop_getattr_args /* { 340 struct vnode *a_vp; 341 struct vattr *a_vap; 342 kauth_cred_t a_cred; 343 } */ *ap = v; 344 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 345 struct vattr *vap = ap->a_vap; 346 347 PTYFS_ITIMES(ptyfs, NULL, NULL, NULL); 348 349 /* start by zeroing out the attributes */ 350 vattr_null(vap); 351 352 /* next do all the common fields */ 353 vap->va_type = ap->a_vp->v_type; 354 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0]; 355 vap->va_fileid = ptyfs->ptyfs_fileno; 356 vap->va_gen = 0; 357 vap->va_flags = 0; 358 vap->va_blocksize = PAGE_SIZE; 359 360 vap->va_atime = ptyfs->ptyfs_atime; 361 vap->va_mtime = ptyfs->ptyfs_mtime; 362 vap->va_ctime = ptyfs->ptyfs_ctime; 363 vap->va_birthtime = ptyfs->ptyfs_birthtime; 364 vap->va_mode = ptyfs->ptyfs_mode; 365 vap->va_flags = ptyfs->ptyfs_flags; 366 vap->va_uid = ptyfs->ptyfs_uid; 367 vap->va_gid = ptyfs->ptyfs_gid; 368 369 switch (ptyfs->ptyfs_type) { 370 case PTYFSpts: 371 case PTYFSptc: 372 if (pty_isfree(ptyfs->ptyfs_pty, 1)) 373 return ENOENT; 374 vap->va_bytes = vap->va_size = 0; 375 vap->va_rdev = ap->a_vp->v_rdev; 376 vap->va_nlink = 1; 377 break; 378 case PTYFSroot: 379 vap->va_rdev = 0; 380 vap->va_bytes = vap->va_size = DEV_BSIZE; 381 vap->va_nlink = 2; 382 break; 383 default: 384 return EOPNOTSUPP; 385 } 386 387 return 0; 388 } 389 390 /*ARGSUSED*/ 391 int 392 ptyfs_setattr(void *v) 393 { 394 struct vop_setattr_args /* { 395 struct vnodeop_desc *a_desc; 396 struct vnode *a_vp; 397 struct vattr *a_vap; 398 kauth_cred_t a_cred; 399 } */ *ap = v; 400 struct vnode *vp = ap->a_vp; 401 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 402 struct vattr *vap = ap->a_vap; 403 kauth_cred_t cred = ap->a_cred; 404 struct lwp *l = curlwp; 405 int error; 406 kauth_action_t action = KAUTH_VNODE_WRITE_FLAGS; 407 bool changing_sysflags = false; 408 409 if (vap->va_size != VNOVALSIZE) { 410 switch (ptyfs->ptyfs_type) { 411 case PTYFSroot: 412 return EISDIR; 413 case PTYFSpts: 414 case PTYFSptc: 415 break; 416 default: 417 return EINVAL; 418 } 419 } 420 421 if (vap->va_flags != VNOVALFLAGS) { 422 if (vp->v_mount->mnt_flag & MNT_RDONLY) 423 return EROFS; 424 425 /* Immutable and append-only flags are not supported on ptyfs. */ 426 if (vap->va_flags & (IMMUTABLE | APPEND)) 427 return EINVAL; 428 429 /* Snapshot flag cannot be set or cleared */ 430 if ((vap->va_flags & SF_SNAPSHOT) != (ptyfs->ptyfs_flags & SF_SNAPSHOT)) 431 return EPERM; 432 433 if ((ptyfs->ptyfs_flags & SF_SETTABLE) != (vap->va_flags & SF_SETTABLE)) { 434 changing_sysflags = true; 435 action |= KAUTH_VNODE_WRITE_SYSFLAGS; 436 } 437 438 error = kauth_authorize_vnode(cred, action, vp, NULL, 439 genfs_can_chflags(vp, cred, ptyfs->ptyfs_uid, 440 changing_sysflags)); 441 if (error) 442 return error; 443 444 if (changing_sysflags) { 445 ptyfs->ptyfs_flags = vap->va_flags; 446 } else { 447 ptyfs->ptyfs_flags &= SF_SETTABLE; 448 ptyfs->ptyfs_flags |= (vap->va_flags & UF_SETTABLE); 449 } 450 ptyfs->ptyfs_status |= PTYFS_CHANGE; 451 } 452 453 /* 454 * Go through the fields and update iff not VNOVAL. 455 */ 456 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { 457 if (vp->v_mount->mnt_flag & MNT_RDONLY) 458 return EROFS; 459 error = ptyfs_chown(vp, vap->va_uid, vap->va_gid, cred, l); 460 if (error) 461 return error; 462 } 463 464 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL || 465 vap->va_birthtime.tv_sec != VNOVAL) { 466 if (vp->v_mount->mnt_flag & MNT_RDONLY) 467 return EROFS; 468 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0) 469 return EPERM; 470 error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_TIMES, vp, 471 NULL, genfs_can_chtimes(vp, cred, ptyfs->ptyfs_uid, 472 vap->va_vaflags)); 473 if (error) 474 return (error); 475 if (vap->va_atime.tv_sec != VNOVAL) 476 if (!(vp->v_mount->mnt_flag & MNT_NOATIME)) 477 ptyfs->ptyfs_status |= PTYFS_ACCESS; 478 if (vap->va_mtime.tv_sec != VNOVAL) { 479 ptyfs->ptyfs_status |= PTYFS_CHANGE | PTYFS_MODIFY; 480 if (vp->v_mount->mnt_flag & MNT_RELATIME) 481 ptyfs->ptyfs_status |= PTYFS_ACCESS; 482 } 483 if (vap->va_birthtime.tv_sec != VNOVAL) 484 ptyfs->ptyfs_birthtime = vap->va_birthtime; 485 ptyfs->ptyfs_status |= PTYFS_CHANGE; 486 error = ptyfs_update(vp, &vap->va_atime, &vap->va_mtime, 0); 487 if (error) 488 return error; 489 } 490 if (vap->va_mode != (mode_t)VNOVAL) { 491 if (vp->v_mount->mnt_flag & MNT_RDONLY) 492 return EROFS; 493 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0 && 494 (vap->va_mode & 495 (S_IXUSR|S_IWUSR|S_IXGRP|S_IWGRP|S_IXOTH|S_IWOTH))) 496 return EPERM; 497 error = ptyfs_chmod(vp, vap->va_mode, cred, l); 498 if (error) 499 return error; 500 } 501 VN_KNOTE(vp, NOTE_ATTRIB); 502 return 0; 503 } 504 505 /* 506 * Change the mode on a file. 507 * Inode must be locked before calling. 508 */ 509 static int 510 ptyfs_chmod(struct vnode *vp, mode_t mode, kauth_cred_t cred, struct lwp *l) 511 { 512 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 513 int error; 514 515 error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_SECURITY, vp, 516 NULL, genfs_can_chmod(vp, cred, ptyfs->ptyfs_uid, ptyfs->ptyfs_gid, 517 mode)); 518 if (error) 519 return (error); 520 521 ptyfs->ptyfs_mode &= ~ALLPERMS; 522 ptyfs->ptyfs_mode |= (mode & ALLPERMS); 523 return 0; 524 } 525 526 /* 527 * Perform chown operation on inode ip; 528 * inode must be locked prior to call. 529 */ 530 static int 531 ptyfs_chown(struct vnode *vp, uid_t uid, gid_t gid, kauth_cred_t cred, 532 struct lwp *l) 533 { 534 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 535 int error; 536 537 if (uid == (uid_t)VNOVAL) 538 uid = ptyfs->ptyfs_uid; 539 if (gid == (gid_t)VNOVAL) 540 gid = ptyfs->ptyfs_gid; 541 542 error = kauth_authorize_vnode(cred, KAUTH_VNODE_CHANGE_OWNERSHIP, vp, 543 NULL, genfs_can_chown(vp, cred, ptyfs->ptyfs_uid, ptyfs->ptyfs_gid, 544 uid, gid)); 545 if (error) 546 return (error); 547 548 ptyfs->ptyfs_gid = gid; 549 ptyfs->ptyfs_uid = uid; 550 return 0; 551 } 552 553 /* 554 * implement access checking. 555 * 556 * actually, the check for super-user is slightly 557 * broken since it will allow read access to write-only 558 * objects. this doesn't cause any particular trouble 559 * but does mean that the i/o entry points need to check 560 * that the operation really does make sense. 561 */ 562 int 563 ptyfs_access(void *v) 564 { 565 struct vop_access_args /* { 566 struct vnode *a_vp; 567 accmode_t a_accmode; 568 kauth_cred_t a_cred; 569 } */ *ap = v; 570 struct vattr va; 571 int error; 572 573 if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred)) != 0) 574 return error; 575 576 return kauth_authorize_vnode(ap->a_cred, 577 KAUTH_ACCESS_ACTION(ap->a_accmode, ap->a_vp->v_type, va.va_mode), 578 ap->a_vp, NULL, genfs_can_access(ap->a_vp, ap->a_cred, va.va_uid, 579 va.va_gid, va.va_mode, NULL, ap->a_accmode)); 580 } 581 582 /* 583 * lookup. this is incredibly complicated in the 584 * general case, however for most pseudo-filesystems 585 * very little needs to be done. 586 * 587 * Locking isn't hard here, just poorly documented. 588 * 589 * If we're looking up ".", just vref the parent & return it. 590 * 591 * If we're looking up "..", unlock the parent, and lock "..". If everything 592 * went ok, try to re-lock the parent. We do this to prevent lock races. 593 * 594 * For anything else, get the needed node. 595 * 596 * We try to exit with the parent locked in error cases. 597 */ 598 int 599 ptyfs_lookup(void *v) 600 { 601 struct vop_lookup_v2_args /* { 602 struct vnode * a_dvp; 603 struct vnode ** a_vpp; 604 struct componentname * a_cnp; 605 } */ *ap = v; 606 struct componentname *cnp = ap->a_cnp; 607 struct vnode **vpp = ap->a_vpp; 608 struct vnode *dvp = ap->a_dvp; 609 const char *pname = cnp->cn_nameptr; 610 struct ptyfsnode *ptyfs; 611 int pty, error; 612 613 *vpp = NULL; 614 615 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 616 return EROFS; 617 618 if (cnp->cn_namelen == 1 && *pname == '.') { 619 *vpp = dvp; 620 vref(dvp); 621 return 0; 622 } 623 624 ptyfs = VTOPTYFS(dvp); 625 switch (ptyfs->ptyfs_type) { 626 case PTYFSroot: 627 /* 628 * Shouldn't get here with .. in the root node. 629 */ 630 if (cnp->cn_flags & ISDOTDOT) 631 return EIO; 632 633 pty = atoi(pname, cnp->cn_namelen); 634 if (pty < 0 || ptyfs_next_active(dvp->v_mount, pty) != pty) 635 break; 636 error = ptyfs_allocvp(dvp->v_mount, vpp, PTYFSpts, pty); 637 if (error) 638 return error; 639 if (ptyfs_next_active(dvp->v_mount, pty) != pty) { 640 vrele(*vpp); 641 *vpp = NULL; 642 return ENOENT; 643 } 644 return 0; 645 646 default: 647 return ENOTDIR; 648 } 649 650 return cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS; 651 } 652 653 /* 654 * readdir returns directory entries from ptyfsnode (vp). 655 * 656 * the strategy here with ptyfs is to generate a single 657 * directory entry at a time (struct dirent) and then 658 * copy that out to userland using uiomove. a more efficent 659 * though more complex implementation, would try to minimize 660 * the number of calls to uiomove(). for ptyfs, this is 661 * hardly worth the added code complexity. 662 * 663 * this should just be done through read() 664 */ 665 int 666 ptyfs_readdir(void *v) 667 { 668 struct vop_readdir_args /* { 669 struct vnode *a_vp; 670 struct uio *a_uio; 671 kauth_cred_t a_cred; 672 int *a_eofflag; 673 off_t **a_cookies; 674 int *a_ncookies; 675 } */ *ap = v; 676 struct uio *uio = ap->a_uio; 677 struct dirent *dp; 678 struct ptyfsnode *ptyfs; 679 off_t i; 680 int error; 681 off_t *cookies = NULL; 682 int ncookies; 683 struct vnode *vp; 684 int n, nc = 0; 685 686 vp = ap->a_vp; 687 ptyfs = VTOPTYFS(vp); 688 689 if (uio->uio_resid < UIO_MX) 690 return EINVAL; 691 if (uio->uio_offset < 0) 692 return EINVAL; 693 694 dp = malloc(sizeof(struct dirent), M_PTYFSTMP, M_WAITOK | M_ZERO); 695 696 error = 0; 697 i = uio->uio_offset; 698 dp->d_reclen = UIO_MX; 699 ncookies = uio->uio_resid / UIO_MX; 700 701 if (ptyfs->ptyfs_type != PTYFSroot) { 702 error = ENOTDIR; 703 goto out; 704 } 705 706 if (i >= npty) 707 goto out; 708 709 if (ap->a_ncookies) { 710 ncookies = uimin(ncookies, (npty + 2 - i)); 711 cookies = malloc(ncookies * sizeof (off_t), 712 M_TEMP, M_WAITOK); 713 *ap->a_cookies = cookies; 714 } 715 716 for (; i < 2; i++) { 717 /* `.' and/or `..' */ 718 dp->d_fileno = PTYFS_FILENO(PTYFSroot, 0); 719 dp->d_namlen = i + 1; 720 (void)memcpy(dp->d_name, "..", dp->d_namlen); 721 dp->d_name[i + 1] = '\0'; 722 dp->d_type = DT_DIR; 723 if ((error = uiomove(dp, UIO_MX, uio)) != 0) 724 goto out; 725 if (cookies) 726 *cookies++ = i + 1; 727 nc++; 728 } 729 while (uio->uio_resid >= UIO_MX) { 730 /* check for used ptys */ 731 n = ptyfs_next_active(vp->v_mount, i - 2); 732 if (n < 0) 733 break; 734 dp->d_fileno = PTYFS_FILENO(PTYFSpts, n); 735 dp->d_namlen = snprintf(dp->d_name, sizeof(dp->d_name), 736 "%lld", (long long)(n)); 737 dp->d_type = DT_CHR; 738 if ((error = uiomove(dp, UIO_MX, uio)) != 0) 739 goto out; 740 i = n + 3; 741 if (cookies) 742 *cookies++ = i; 743 nc++; 744 } 745 746 out: 747 /* not pertinent in error cases */ 748 ncookies = nc; 749 750 if (ap->a_ncookies) { 751 if (error) { 752 if (cookies) 753 free(*ap->a_cookies, M_TEMP); 754 *ap->a_ncookies = 0; 755 *ap->a_cookies = NULL; 756 } else 757 *ap->a_ncookies = ncookies; 758 } 759 uio->uio_offset = i; 760 free(dp, M_PTYFSTMP); 761 return error; 762 } 763 764 int 765 ptyfs_open(void *v) 766 { 767 struct vop_open_args /* { 768 struct vnode *a_vp; 769 int a_mode; 770 kauth_cred_t a_cred; 771 } */ *ap = v; 772 struct vnode *vp = ap->a_vp; 773 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 774 775 switch (ptyfs->ptyfs_type) { 776 case PTYFSpts: 777 case PTYFSptc: 778 return spec_open(v); 779 case PTYFSroot: 780 return 0; 781 default: 782 return EINVAL; 783 } 784 } 785 786 int 787 ptyfs_close(void *v) 788 { 789 struct vop_close_args /* { 790 struct vnode *a_vp; 791 int a_fflag; 792 kauth_cred_t a_cred; 793 } */ *ap = v; 794 struct vnode *vp = ap->a_vp; 795 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 796 797 mutex_enter(vp->v_interlock); 798 if (vrefcnt(vp) > 1) 799 PTYFS_ITIMES(ptyfs, NULL, NULL, NULL); 800 mutex_exit(vp->v_interlock); 801 802 switch (ptyfs->ptyfs_type) { 803 case PTYFSpts: 804 case PTYFSptc: 805 return spec_close(v); 806 case PTYFSroot: 807 return 0; 808 default: 809 return EINVAL; 810 } 811 } 812 813 int 814 ptyfs_read(void *v) 815 { 816 struct vop_read_args /* { 817 struct vnode *a_vp; 818 struct uio *a_uio; 819 int a_ioflag; 820 kauth_cred_t a_cred; 821 } */ *ap = v; 822 struct timespec ts; 823 struct vnode *vp = ap->a_vp; 824 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 825 int error; 826 827 if (vp->v_type == VDIR) 828 return EISDIR; 829 830 ptyfs->ptyfs_status |= PTYFS_ACCESS; 831 /* hardclock() resolution is good enough for ptyfs */ 832 getnanotime(&ts); 833 (void)ptyfs_update(vp, &ts, &ts, 0); 834 835 switch (ptyfs->ptyfs_type) { 836 case PTYFSpts: 837 case PTYFSptc: 838 VOP_UNLOCK(vp); 839 error = cdev_read(vp->v_rdev, ap->a_uio, ap->a_ioflag); 840 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 841 return error; 842 default: 843 return EOPNOTSUPP; 844 } 845 } 846 847 int 848 ptyfs_write(void *v) 849 { 850 struct vop_write_args /* { 851 struct vnode *a_vp; 852 struct uio *a_uio; 853 int a_ioflag; 854 kauth_cred_t a_cred; 855 } */ *ap = v; 856 struct timespec ts; 857 struct vnode *vp = ap->a_vp; 858 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 859 int error; 860 861 ptyfs->ptyfs_status |= PTYFS_MODIFY; 862 getnanotime(&ts); 863 (void)ptyfs_update(vp, &ts, &ts, 0); 864 865 switch (ptyfs->ptyfs_type) { 866 case PTYFSpts: 867 case PTYFSptc: 868 VOP_UNLOCK(vp); 869 error = cdev_write(vp->v_rdev, ap->a_uio, ap->a_ioflag); 870 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 871 return error; 872 default: 873 return EOPNOTSUPP; 874 } 875 } 876 877 int 878 ptyfs_ioctl(void *v) 879 { 880 struct vop_ioctl_args /* { 881 struct vnode *a_vp; 882 u_long a_command; 883 void *a_data; 884 int a_fflag; 885 kauth_cred_t a_cred; 886 } */ *ap = v; 887 struct vnode *vp = ap->a_vp; 888 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 889 890 switch (ptyfs->ptyfs_type) { 891 case PTYFSpts: 892 case PTYFSptc: 893 return cdev_ioctl(vp->v_rdev, ap->a_command, 894 ap->a_data, ap->a_fflag, curlwp); 895 default: 896 return EOPNOTSUPP; 897 } 898 } 899 900 int 901 ptyfs_poll(void *v) 902 { 903 struct vop_poll_args /* { 904 struct vnode *a_vp; 905 int a_events; 906 } */ *ap = v; 907 struct vnode *vp = ap->a_vp; 908 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 909 910 switch (ptyfs->ptyfs_type) { 911 case PTYFSpts: 912 case PTYFSptc: 913 return cdev_poll(vp->v_rdev, ap->a_events, curlwp); 914 default: 915 return genfs_poll(v); 916 } 917 } 918 919 int 920 ptyfs_kqfilter(void *v) 921 { 922 struct vop_kqfilter_args /* { 923 struct vnode *a_vp; 924 struct knote *a_kn; 925 } */ *ap = v; 926 struct vnode *vp = ap->a_vp; 927 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 928 929 switch (ptyfs->ptyfs_type) { 930 case PTYFSpts: 931 case PTYFSptc: 932 return cdev_kqfilter(vp->v_rdev, ap->a_kn); 933 default: 934 return genfs_kqfilter(v); 935 } 936 } 937 938 static int 939 ptyfs_update(struct vnode *vp, const struct timespec *acc, 940 const struct timespec *mod, int flags) 941 { 942 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 943 944 if (vp->v_mount->mnt_flag & MNT_RDONLY) 945 return 0; 946 947 PTYFS_ITIMES(ptyfs, acc, mod, NULL); 948 return 0; 949 } 950 951 void 952 ptyfs_itimes(struct ptyfsnode *ptyfs, const struct timespec *acc, 953 const struct timespec *mod, const struct timespec *cre) 954 { 955 struct timespec now; 956 957 KASSERT(ptyfs->ptyfs_status & (PTYFS_ACCESS|PTYFS_CHANGE|PTYFS_MODIFY)); 958 959 getnanotime(&now); 960 if (ptyfs->ptyfs_status & PTYFS_ACCESS) { 961 if (acc == NULL) 962 acc = &now; 963 ptyfs->ptyfs_atime = *acc; 964 } 965 if (ptyfs->ptyfs_status & PTYFS_MODIFY) { 966 if (mod == NULL) 967 mod = &now; 968 ptyfs->ptyfs_mtime = *mod; 969 } 970 if (ptyfs->ptyfs_status & PTYFS_CHANGE) { 971 if (cre == NULL) 972 cre = &now; 973 ptyfs->ptyfs_ctime = *cre; 974 } 975 ptyfs->ptyfs_status &= ~(PTYFS_ACCESS|PTYFS_CHANGE|PTYFS_MODIFY); 976 } 977 978 /* 979 * convert decimal ascii to int 980 */ 981 static int 982 atoi(const char *b, size_t len) 983 { 984 int p = 0; 985 986 while (len--) { 987 char c = *b++; 988 if (c < '0' || c > '9') 989 return -1; 990 p = 10 * p + (c - '0'); 991 } 992 993 return p; 994 } 995
Indexes created Fri Sep 26 08:10:20 GMT 2025