ptyfs_vnops.c revision 1.62.4.1
1 /* $NetBSD: ptyfs_vnops.c,v 1.62.4.1 2021/08/01 22:42:37 thorpej 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 1.62.4.1 2021/08/01 22:42:37 thorpej 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 int ptyfs_open (void *); 118 int ptyfs_close (void *); 119 int ptyfs_access (void *); 120 int ptyfs_getattr (void *); 121 int ptyfs_setattr (void *); 122 int ptyfs_read (void *); 123 int ptyfs_write (void *); 124 int ptyfs_ioctl (void *); 125 int ptyfs_poll (void *); 126 int ptyfs_kqfilter (void *); 127 int ptyfs_readdir (void *); 128 int ptyfs_reclaim (void *); 129 int ptyfs_inactive (void *); 130 int ptyfs_print (void *); 131 int ptyfs_pathconf (void *); 132 int ptyfs_advlock (void *); 133 134 static int ptyfs_update(struct vnode *, const struct timespec *, 135 const struct timespec *, int); 136 static int ptyfs_chown(struct vnode *, uid_t, gid_t, kauth_cred_t, 137 struct lwp *); 138 static int ptyfs_chmod(struct vnode *, mode_t, kauth_cred_t, struct lwp *); 139 static int atoi(const char *, size_t); 140 141 /* 142 * ptyfs vnode operations. 143 */ 144 int (**ptyfs_vnodeop_p)(void *); 145 const struct vnodeopv_entry_desc ptyfs_vnodeop_entries[] = { 146 { &vop_default_desc, vn_default_error }, 147 { &vop_parsepath_desc, genfs_parsepath }, /* parsepath */ 148 { &vop_lookup_desc, ptyfs_lookup }, /* lookup */ 149 { &vop_create_desc, genfs_eopnotsupp }, /* create */ 150 { &vop_mknod_desc, genfs_eopnotsupp }, /* mknod */ 151 { &vop_open_desc, ptyfs_open }, /* open */ 152 { &vop_close_desc, ptyfs_close }, /* close */ 153 { &vop_access_desc, ptyfs_access }, /* access */ 154 { &vop_accessx_desc, genfs_accessx }, /* accessx */ 155 { &vop_getattr_desc, ptyfs_getattr }, /* getattr */ 156 { &vop_setattr_desc, ptyfs_setattr }, /* setattr */ 157 { &vop_read_desc, ptyfs_read }, /* read */ 158 { &vop_write_desc, ptyfs_write }, /* write */ 159 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */ 160 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */ 161 { &vop_ioctl_desc, ptyfs_ioctl }, /* ioctl */ 162 { &vop_fcntl_desc, genfs_fcntl }, /* fcntl */ 163 { &vop_poll_desc, ptyfs_poll }, /* poll */ 164 { &vop_kqfilter_desc, ptyfs_kqfilter }, /* kqfilter */ 165 { &vop_revoke_desc, genfs_revoke }, /* revoke */ 166 { &vop_mmap_desc, genfs_eopnotsupp }, /* mmap */ 167 { &vop_fsync_desc, genfs_nullop }, /* fsync */ 168 { &vop_seek_desc, genfs_nullop }, /* seek */ 169 { &vop_remove_desc, genfs_eopnotsupp }, /* remove */ 170 { &vop_link_desc, genfs_eopnotsupp }, /* link */ 171 { &vop_rename_desc, genfs_eopnotsupp }, /* rename */ 172 { &vop_mkdir_desc, genfs_eopnotsupp }, /* mkdir */ 173 { &vop_rmdir_desc, genfs_eopnotsupp }, /* rmdir */ 174 { &vop_symlink_desc, genfs_eopnotsupp }, /* symlink */ 175 { &vop_readdir_desc, ptyfs_readdir }, /* readdir */ 176 { &vop_readlink_desc, genfs_eopnotsupp }, /* readlink */ 177 { &vop_abortop_desc, genfs_abortop }, /* abortop */ 178 { &vop_inactive_desc, ptyfs_inactive }, /* inactive */ 179 { &vop_reclaim_desc, ptyfs_reclaim }, /* reclaim */ 180 { &vop_lock_desc, genfs_lock }, /* lock */ 181 { &vop_unlock_desc, genfs_unlock }, /* unlock */ 182 { &vop_bmap_desc, genfs_eopnotsupp }, /* bmap */ 183 { &vop_strategy_desc, genfs_badop }, /* strategy */ 184 { &vop_print_desc, ptyfs_print }, /* print */ 185 { &vop_islocked_desc, genfs_islocked }, /* islocked */ 186 { &vop_pathconf_desc, ptyfs_pathconf }, /* pathconf */ 187 { &vop_advlock_desc, ptyfs_advlock }, /* advlock */ 188 { &vop_bwrite_desc, genfs_eopnotsupp }, /* bwrite */ 189 { &vop_putpages_desc, genfs_null_putpages }, /* putpages */ 190 { NULL, NULL } 191 }; 192 const struct vnodeopv_desc ptyfs_vnodeop_opv_desc = 193 { &ptyfs_vnodeop_p, ptyfs_vnodeop_entries }; 194 195 /* 196 * free any private data and remove the node 197 * from any private lists. 198 */ 199 int 200 ptyfs_reclaim(void *v) 201 { 202 struct vop_reclaim_v2_args /* { 203 struct vnode *a_vp; 204 } */ *ap = v; 205 struct vnode *vp = ap->a_vp; 206 207 VOP_UNLOCK(vp); 208 209 vp->v_data = NULL; 210 return 0; 211 } 212 213 int 214 ptyfs_inactive(void *v) 215 { 216 struct vop_inactive_v2_args /* { 217 struct vnode *a_vp; 218 bool *a_recycle; 219 } */ *ap = v; 220 struct vnode *vp = ap->a_vp; 221 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 222 223 if (ptyfs->ptyfs_type == PTYFSptc) 224 ptyfs_clr_active(vp->v_mount, ptyfs->ptyfs_pty); 225 226 return 0; 227 } 228 229 /* 230 * Return POSIX pathconf information applicable to special devices. 231 */ 232 int 233 ptyfs_pathconf(void *v) 234 { 235 struct vop_pathconf_args /* { 236 struct vnode *a_vp; 237 int a_name; 238 register_t *a_retval; 239 } */ *ap = v; 240 241 switch (ap->a_name) { 242 case _PC_LINK_MAX: 243 *ap->a_retval = LINK_MAX; 244 return 0; 245 case _PC_MAX_CANON: 246 *ap->a_retval = MAX_CANON; 247 return 0; 248 case _PC_MAX_INPUT: 249 *ap->a_retval = MAX_INPUT; 250 return 0; 251 case _PC_PIPE_BUF: 252 *ap->a_retval = PIPE_BUF; 253 return 0; 254 case _PC_CHOWN_RESTRICTED: 255 *ap->a_retval = 1; 256 return 0; 257 case _PC_VDISABLE: 258 *ap->a_retval = _POSIX_VDISABLE; 259 return 0; 260 case _PC_SYNC_IO: 261 *ap->a_retval = 1; 262 return 0; 263 default: 264 return genfs_pathconf(ap); 265 } 266 } 267 268 /* 269 * _print is used for debugging. 270 * just print a readable description 271 * of (vp). 272 */ 273 int 274 ptyfs_print(void *v) 275 { 276 struct vop_print_args /* { 277 struct vnode *a_vp; 278 } */ *ap = v; 279 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 280 281 printf("tag VT_PTYFS, type %d, pty %d\n", 282 ptyfs->ptyfs_type, ptyfs->ptyfs_pty); 283 return 0; 284 } 285 286 /* 287 * support advisory locking on pty nodes 288 */ 289 int 290 ptyfs_advlock(void *v) 291 { 292 struct vop_print_args /* { 293 struct vnode *a_vp; 294 } */ *ap = v; 295 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 296 297 switch (ptyfs->ptyfs_type) { 298 case PTYFSpts: 299 case PTYFSptc: 300 return spec_advlock(v); 301 default: 302 return EOPNOTSUPP; 303 } 304 } 305 306 /* 307 * Invent attributes for ptyfsnode (vp) and store 308 * them in (vap). 309 * Directories lengths are returned as zero since 310 * any real length would require the genuine size 311 * to be computed, and nothing cares anyway. 312 * 313 * this is relatively minimal for ptyfs. 314 */ 315 int 316 ptyfs_getattr(void *v) 317 { 318 struct vop_getattr_args /* { 319 struct vnode *a_vp; 320 struct vattr *a_vap; 321 kauth_cred_t a_cred; 322 } */ *ap = v; 323 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 324 struct vattr *vap = ap->a_vap; 325 326 PTYFS_ITIMES(ptyfs, NULL, NULL, NULL); 327 328 /* start by zeroing out the attributes */ 329 vattr_null(vap); 330 331 /* next do all the common fields */ 332 vap->va_type = ap->a_vp->v_type; 333 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0]; 334 vap->va_fileid = ptyfs->ptyfs_fileno; 335 vap->va_gen = 0; 336 vap->va_flags = 0; 337 vap->va_blocksize = PAGE_SIZE; 338 339 vap->va_atime = ptyfs->ptyfs_atime; 340 vap->va_mtime = ptyfs->ptyfs_mtime; 341 vap->va_ctime = ptyfs->ptyfs_ctime; 342 vap->va_birthtime = ptyfs->ptyfs_birthtime; 343 vap->va_mode = ptyfs->ptyfs_mode; 344 vap->va_flags = ptyfs->ptyfs_flags; 345 vap->va_uid = ptyfs->ptyfs_uid; 346 vap->va_gid = ptyfs->ptyfs_gid; 347 348 switch (ptyfs->ptyfs_type) { 349 case PTYFSpts: 350 case PTYFSptc: 351 if (pty_isfree(ptyfs->ptyfs_pty, 1)) 352 return ENOENT; 353 vap->va_bytes = vap->va_size = 0; 354 vap->va_rdev = ap->a_vp->v_rdev; 355 vap->va_nlink = 1; 356 break; 357 case PTYFSroot: 358 vap->va_rdev = 0; 359 vap->va_bytes = vap->va_size = DEV_BSIZE; 360 vap->va_nlink = 2; 361 break; 362 default: 363 return EOPNOTSUPP; 364 } 365 366 return 0; 367 } 368 369 /*ARGSUSED*/ 370 int 371 ptyfs_setattr(void *v) 372 { 373 struct vop_setattr_args /* { 374 struct vnodeop_desc *a_desc; 375 struct vnode *a_vp; 376 struct vattr *a_vap; 377 kauth_cred_t a_cred; 378 } */ *ap = v; 379 struct vnode *vp = ap->a_vp; 380 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 381 struct vattr *vap = ap->a_vap; 382 kauth_cred_t cred = ap->a_cred; 383 struct lwp *l = curlwp; 384 int error; 385 kauth_action_t action = KAUTH_VNODE_WRITE_FLAGS; 386 bool changing_sysflags = false; 387 388 if (vap->va_size != VNOVALSIZE) { 389 switch (ptyfs->ptyfs_type) { 390 case PTYFSroot: 391 return EISDIR; 392 case PTYFSpts: 393 case PTYFSptc: 394 break; 395 default: 396 return EINVAL; 397 } 398 } 399 400 if (vap->va_flags != VNOVALFLAGS) { 401 if (vp->v_mount->mnt_flag & MNT_RDONLY) 402 return EROFS; 403 404 /* Immutable and append-only flags are not supported on ptyfs. */ 405 if (vap->va_flags & (IMMUTABLE | APPEND)) 406 return EINVAL; 407 408 /* Snapshot flag cannot be set or cleared */ 409 if ((vap->va_flags & SF_SNAPSHOT) != (ptyfs->ptyfs_flags & SF_SNAPSHOT)) 410 return EPERM; 411 412 if ((ptyfs->ptyfs_flags & SF_SETTABLE) != (vap->va_flags & SF_SETTABLE)) { 413 changing_sysflags = true; 414 action |= KAUTH_VNODE_WRITE_SYSFLAGS; 415 } 416 417 error = kauth_authorize_vnode(cred, action, vp, NULL, 418 genfs_can_chflags(vp, cred, ptyfs->ptyfs_uid, 419 changing_sysflags)); 420 if (error) 421 return error; 422 423 if (changing_sysflags) { 424 ptyfs->ptyfs_flags = vap->va_flags; 425 } else { 426 ptyfs->ptyfs_flags &= SF_SETTABLE; 427 ptyfs->ptyfs_flags |= (vap->va_flags & UF_SETTABLE); 428 } 429 ptyfs->ptyfs_status |= PTYFS_CHANGE; 430 } 431 432 /* 433 * Go through the fields and update iff not VNOVAL. 434 */ 435 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { 436 if (vp->v_mount->mnt_flag & MNT_RDONLY) 437 return EROFS; 438 error = ptyfs_chown(vp, vap->va_uid, vap->va_gid, cred, l); 439 if (error) 440 return error; 441 } 442 443 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL || 444 vap->va_birthtime.tv_sec != VNOVAL) { 445 if (vp->v_mount->mnt_flag & MNT_RDONLY) 446 return EROFS; 447 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0) 448 return EPERM; 449 error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_TIMES, vp, 450 NULL, genfs_can_chtimes(vp, cred, ptyfs->ptyfs_uid, 451 vap->va_vaflags)); 452 if (error) 453 return (error); 454 if (vap->va_atime.tv_sec != VNOVAL) 455 if (!(vp->v_mount->mnt_flag & MNT_NOATIME)) 456 ptyfs->ptyfs_status |= PTYFS_ACCESS; 457 if (vap->va_mtime.tv_sec != VNOVAL) { 458 ptyfs->ptyfs_status |= PTYFS_CHANGE | PTYFS_MODIFY; 459 if (vp->v_mount->mnt_flag & MNT_RELATIME) 460 ptyfs->ptyfs_status |= PTYFS_ACCESS; 461 } 462 if (vap->va_birthtime.tv_sec != VNOVAL) 463 ptyfs->ptyfs_birthtime = vap->va_birthtime; 464 ptyfs->ptyfs_status |= PTYFS_CHANGE; 465 error = ptyfs_update(vp, &vap->va_atime, &vap->va_mtime, 0); 466 if (error) 467 return error; 468 } 469 if (vap->va_mode != (mode_t)VNOVAL) { 470 if (vp->v_mount->mnt_flag & MNT_RDONLY) 471 return EROFS; 472 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0 && 473 (vap->va_mode & 474 (S_IXUSR|S_IWUSR|S_IXGRP|S_IWGRP|S_IXOTH|S_IWOTH))) 475 return EPERM; 476 error = ptyfs_chmod(vp, vap->va_mode, cred, l); 477 if (error) 478 return error; 479 } 480 VN_KNOTE(vp, NOTE_ATTRIB); 481 return 0; 482 } 483 484 /* 485 * Change the mode on a file. 486 * Inode must be locked before calling. 487 */ 488 static int 489 ptyfs_chmod(struct vnode *vp, mode_t mode, kauth_cred_t cred, struct lwp *l) 490 { 491 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 492 int error; 493 494 error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_SECURITY, vp, 495 NULL, genfs_can_chmod(vp, cred, ptyfs->ptyfs_uid, ptyfs->ptyfs_gid, 496 mode)); 497 if (error) 498 return (error); 499 500 ptyfs->ptyfs_mode &= ~ALLPERMS; 501 ptyfs->ptyfs_mode |= (mode & ALLPERMS); 502 return 0; 503 } 504 505 /* 506 * Perform chown operation on inode ip; 507 * inode must be locked prior to call. 508 */ 509 static int 510 ptyfs_chown(struct vnode *vp, uid_t uid, gid_t gid, kauth_cred_t cred, 511 struct lwp *l) 512 { 513 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 514 int error; 515 516 if (uid == (uid_t)VNOVAL) 517 uid = ptyfs->ptyfs_uid; 518 if (gid == (gid_t)VNOVAL) 519 gid = ptyfs->ptyfs_gid; 520 521 error = kauth_authorize_vnode(cred, KAUTH_VNODE_CHANGE_OWNERSHIP, vp, 522 NULL, genfs_can_chown(vp, cred, ptyfs->ptyfs_uid, ptyfs->ptyfs_gid, 523 uid, gid)); 524 if (error) 525 return (error); 526 527 ptyfs->ptyfs_gid = gid; 528 ptyfs->ptyfs_uid = uid; 529 return 0; 530 } 531 532 /* 533 * implement access checking. 534 * 535 * actually, the check for super-user is slightly 536 * broken since it will allow read access to write-only 537 * objects. this doesn't cause any particular trouble 538 * but does mean that the i/o entry points need to check 539 * that the operation really does make sense. 540 */ 541 int 542 ptyfs_access(void *v) 543 { 544 struct vop_access_args /* { 545 struct vnode *a_vp; 546 accmode_t a_accmode; 547 kauth_cred_t a_cred; 548 } */ *ap = v; 549 struct vattr va; 550 int error; 551 552 if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred)) != 0) 553 return error; 554 555 return kauth_authorize_vnode(ap->a_cred, 556 KAUTH_ACCESS_ACTION(ap->a_accmode, ap->a_vp->v_type, va.va_mode), 557 ap->a_vp, NULL, genfs_can_access(ap->a_vp, ap->a_cred, va.va_uid, 558 va.va_gid, va.va_mode, NULL, ap->a_accmode)); 559 } 560 561 /* 562 * lookup. this is incredibly complicated in the 563 * general case, however for most pseudo-filesystems 564 * very little needs to be done. 565 * 566 * Locking isn't hard here, just poorly documented. 567 * 568 * If we're looking up ".", just vref the parent & return it. 569 * 570 * If we're looking up "..", unlock the parent, and lock "..". If everything 571 * went ok, try to re-lock the parent. We do this to prevent lock races. 572 * 573 * For anything else, get the needed node. 574 * 575 * We try to exit with the parent locked in error cases. 576 */ 577 int 578 ptyfs_lookup(void *v) 579 { 580 struct vop_lookup_v2_args /* { 581 struct vnode * a_dvp; 582 struct vnode ** a_vpp; 583 struct componentname * a_cnp; 584 } */ *ap = v; 585 struct componentname *cnp = ap->a_cnp; 586 struct vnode **vpp = ap->a_vpp; 587 struct vnode *dvp = ap->a_dvp; 588 const char *pname = cnp->cn_nameptr; 589 struct ptyfsnode *ptyfs; 590 int pty, error; 591 592 *vpp = NULL; 593 594 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 595 return EROFS; 596 597 if (cnp->cn_namelen == 1 && *pname == '.') { 598 *vpp = dvp; 599 vref(dvp); 600 return 0; 601 } 602 603 ptyfs = VTOPTYFS(dvp); 604 switch (ptyfs->ptyfs_type) { 605 case PTYFSroot: 606 /* 607 * Shouldn't get here with .. in the root node. 608 */ 609 if (cnp->cn_flags & ISDOTDOT) 610 return EIO; 611 612 pty = atoi(pname, cnp->cn_namelen); 613 if (pty < 0 || ptyfs_next_active(dvp->v_mount, pty) != pty) 614 break; 615 error = ptyfs_allocvp(dvp->v_mount, vpp, PTYFSpts, pty); 616 if (error) 617 return error; 618 if (ptyfs_next_active(dvp->v_mount, pty) != pty) { 619 vrele(*vpp); 620 *vpp = NULL; 621 return ENOENT; 622 } 623 return 0; 624 625 default: 626 return ENOTDIR; 627 } 628 629 return cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS; 630 } 631 632 /* 633 * readdir returns directory entries from ptyfsnode (vp). 634 * 635 * the strategy here with ptyfs is to generate a single 636 * directory entry at a time (struct dirent) and then 637 * copy that out to userland using uiomove. a more efficent 638 * though more complex implementation, would try to minimize 639 * the number of calls to uiomove(). for ptyfs, this is 640 * hardly worth the added code complexity. 641 * 642 * this should just be done through read() 643 */ 644 int 645 ptyfs_readdir(void *v) 646 { 647 struct vop_readdir_args /* { 648 struct vnode *a_vp; 649 struct uio *a_uio; 650 kauth_cred_t a_cred; 651 int *a_eofflag; 652 off_t **a_cookies; 653 int *a_ncookies; 654 } */ *ap = v; 655 struct uio *uio = ap->a_uio; 656 struct dirent *dp; 657 struct ptyfsnode *ptyfs; 658 off_t i; 659 int error; 660 off_t *cookies = NULL; 661 int ncookies; 662 struct vnode *vp; 663 int n, nc = 0; 664 665 vp = ap->a_vp; 666 ptyfs = VTOPTYFS(vp); 667 668 if (uio->uio_resid < UIO_MX) 669 return EINVAL; 670 if (uio->uio_offset < 0) 671 return EINVAL; 672 673 dp = malloc(sizeof(struct dirent), M_PTYFSTMP, M_WAITOK | M_ZERO); 674 675 error = 0; 676 i = uio->uio_offset; 677 dp->d_reclen = UIO_MX; 678 ncookies = uio->uio_resid / UIO_MX; 679 680 if (ptyfs->ptyfs_type != PTYFSroot) { 681 error = ENOTDIR; 682 goto out; 683 } 684 685 if (i >= npty) 686 goto out; 687 688 if (ap->a_ncookies) { 689 ncookies = uimin(ncookies, (npty + 2 - i)); 690 cookies = malloc(ncookies * sizeof (off_t), 691 M_TEMP, M_WAITOK); 692 *ap->a_cookies = cookies; 693 } 694 695 for (; i < 2; i++) { 696 /* `.' and/or `..' */ 697 dp->d_fileno = PTYFS_FILENO(PTYFSroot, 0); 698 dp->d_namlen = i + 1; 699 (void)memcpy(dp->d_name, "..", dp->d_namlen); 700 dp->d_name[i + 1] = '\0'; 701 dp->d_type = DT_DIR; 702 if ((error = uiomove(dp, UIO_MX, uio)) != 0) 703 goto out; 704 if (cookies) 705 *cookies++ = i + 1; 706 nc++; 707 } 708 while (uio->uio_resid >= UIO_MX) { 709 /* check for used ptys */ 710 n = ptyfs_next_active(vp->v_mount, i - 2); 711 if (n < 0) 712 break; 713 dp->d_fileno = PTYFS_FILENO(PTYFSpts, n); 714 dp->d_namlen = snprintf(dp->d_name, sizeof(dp->d_name), 715 "%lld", (long long)(n)); 716 dp->d_type = DT_CHR; 717 if ((error = uiomove(dp, UIO_MX, uio)) != 0) 718 goto out; 719 i = n + 3; 720 if (cookies) 721 *cookies++ = i; 722 nc++; 723 } 724 725 out: 726 /* not pertinent in error cases */ 727 ncookies = nc; 728 729 if (ap->a_ncookies) { 730 if (error) { 731 if (cookies) 732 free(*ap->a_cookies, M_TEMP); 733 *ap->a_ncookies = 0; 734 *ap->a_cookies = NULL; 735 } else 736 *ap->a_ncookies = ncookies; 737 } 738 uio->uio_offset = i; 739 free(dp, M_PTYFSTMP); 740 return error; 741 } 742 743 int 744 ptyfs_open(void *v) 745 { 746 struct vop_open_args /* { 747 struct vnode *a_vp; 748 int a_mode; 749 kauth_cred_t a_cred; 750 } */ *ap = v; 751 struct vnode *vp = ap->a_vp; 752 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 753 754 switch (ptyfs->ptyfs_type) { 755 case PTYFSpts: 756 case PTYFSptc: 757 return spec_open(v); 758 case PTYFSroot: 759 return 0; 760 default: 761 return EINVAL; 762 } 763 } 764 765 int 766 ptyfs_close(void *v) 767 { 768 struct vop_close_args /* { 769 struct vnode *a_vp; 770 int a_fflag; 771 kauth_cred_t a_cred; 772 } */ *ap = v; 773 struct vnode *vp = ap->a_vp; 774 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 775 776 mutex_enter(vp->v_interlock); 777 if (vrefcnt(vp) > 1) 778 PTYFS_ITIMES(ptyfs, NULL, NULL, NULL); 779 mutex_exit(vp->v_interlock); 780 781 switch (ptyfs->ptyfs_type) { 782 case PTYFSpts: 783 case PTYFSptc: 784 return spec_close(v); 785 case PTYFSroot: 786 return 0; 787 default: 788 return EINVAL; 789 } 790 } 791 792 int 793 ptyfs_read(void *v) 794 { 795 struct vop_read_args /* { 796 struct vnode *a_vp; 797 struct uio *a_uio; 798 int a_ioflag; 799 kauth_cred_t a_cred; 800 } */ *ap = v; 801 struct timespec ts; 802 struct vnode *vp = ap->a_vp; 803 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 804 int error; 805 806 if (vp->v_type == VDIR) 807 return EISDIR; 808 809 ptyfs->ptyfs_status |= PTYFS_ACCESS; 810 /* hardclock() resolution is good enough for ptyfs */ 811 getnanotime(&ts); 812 (void)ptyfs_update(vp, &ts, &ts, 0); 813 814 switch (ptyfs->ptyfs_type) { 815 case PTYFSpts: 816 case PTYFSptc: 817 VOP_UNLOCK(vp); 818 error = cdev_read(vp->v_rdev, ap->a_uio, ap->a_ioflag); 819 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 820 return error; 821 default: 822 return EOPNOTSUPP; 823 } 824 } 825 826 int 827 ptyfs_write(void *v) 828 { 829 struct vop_write_args /* { 830 struct vnode *a_vp; 831 struct uio *a_uio; 832 int a_ioflag; 833 kauth_cred_t a_cred; 834 } */ *ap = v; 835 struct timespec ts; 836 struct vnode *vp = ap->a_vp; 837 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 838 int error; 839 840 ptyfs->ptyfs_status |= PTYFS_MODIFY; 841 getnanotime(&ts); 842 (void)ptyfs_update(vp, &ts, &ts, 0); 843 844 switch (ptyfs->ptyfs_type) { 845 case PTYFSpts: 846 case PTYFSptc: 847 VOP_UNLOCK(vp); 848 error = cdev_write(vp->v_rdev, ap->a_uio, ap->a_ioflag); 849 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 850 return error; 851 default: 852 return EOPNOTSUPP; 853 } 854 } 855 856 int 857 ptyfs_ioctl(void *v) 858 { 859 struct vop_ioctl_args /* { 860 struct vnode *a_vp; 861 u_long a_command; 862 void *a_data; 863 int a_fflag; 864 kauth_cred_t a_cred; 865 } */ *ap = v; 866 struct vnode *vp = ap->a_vp; 867 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 868 869 switch (ptyfs->ptyfs_type) { 870 case PTYFSpts: 871 case PTYFSptc: 872 return cdev_ioctl(vp->v_rdev, ap->a_command, 873 ap->a_data, ap->a_fflag, curlwp); 874 default: 875 return EOPNOTSUPP; 876 } 877 } 878 879 int 880 ptyfs_poll(void *v) 881 { 882 struct vop_poll_args /* { 883 struct vnode *a_vp; 884 int a_events; 885 } */ *ap = v; 886 struct vnode *vp = ap->a_vp; 887 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 888 889 switch (ptyfs->ptyfs_type) { 890 case PTYFSpts: 891 case PTYFSptc: 892 return cdev_poll(vp->v_rdev, ap->a_events, curlwp); 893 default: 894 return genfs_poll(v); 895 } 896 } 897 898 int 899 ptyfs_kqfilter(void *v) 900 { 901 struct vop_kqfilter_args /* { 902 struct vnode *a_vp; 903 struct knote *a_kn; 904 } */ *ap = v; 905 struct vnode *vp = ap->a_vp; 906 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 907 908 switch (ptyfs->ptyfs_type) { 909 case PTYFSpts: 910 case PTYFSptc: 911 return cdev_kqfilter(vp->v_rdev, ap->a_kn); 912 default: 913 return genfs_kqfilter(v); 914 } 915 } 916 917 static int 918 ptyfs_update(struct vnode *vp, const struct timespec *acc, 919 const struct timespec *mod, int flags) 920 { 921 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 922 923 if (vp->v_mount->mnt_flag & MNT_RDONLY) 924 return 0; 925 926 PTYFS_ITIMES(ptyfs, acc, mod, NULL); 927 return 0; 928 } 929 930 void 931 ptyfs_itimes(struct ptyfsnode *ptyfs, const struct timespec *acc, 932 const struct timespec *mod, const struct timespec *cre) 933 { 934 struct timespec now; 935 936 KASSERT(ptyfs->ptyfs_status & (PTYFS_ACCESS|PTYFS_CHANGE|PTYFS_MODIFY)); 937 938 getnanotime(&now); 939 if (ptyfs->ptyfs_status & PTYFS_ACCESS) { 940 if (acc == NULL) 941 acc = &now; 942 ptyfs->ptyfs_atime = *acc; 943 } 944 if (ptyfs->ptyfs_status & PTYFS_MODIFY) { 945 if (mod == NULL) 946 mod = &now; 947 ptyfs->ptyfs_mtime = *mod; 948 } 949 if (ptyfs->ptyfs_status & PTYFS_CHANGE) { 950 if (cre == NULL) 951 cre = &now; 952 ptyfs->ptyfs_ctime = *cre; 953 } 954 ptyfs->ptyfs_status &= ~(PTYFS_ACCESS|PTYFS_CHANGE|PTYFS_MODIFY); 955 } 956 957 /* 958 * convert decimal ascii to int 959 */ 960 static int 961 atoi(const char *b, size_t len) 962 { 963 int p = 0; 964 965 while (len--) { 966 char c = *b++; 967 if (c < '0' || c > '9') 968 return -1; 969 p = 10 * p + (c - '0'); 970 } 971 972 return p; 973 } 974
Indexes created Wed Oct 22 13:09:56 GMT 2025