ptyfs_vnops.c revision 1.8
1 /* $NetBSD: ptyfs_vnops.c,v 1.8 2005/09/12 16:37:13 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 1.8 2005/09/12 16:37:13 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> 99 100 #include <uvm/uvm_extern.h> /* for PAGE_SIZE */ 101 102 #include <machine/reg.h> 103 104 #include <fs/ptyfs/ptyfs.h> 105 #include <miscfs/genfs/genfs.h> 106 #include <miscfs/specfs/specdev.h> 107 108 /* 109 * Vnode Operations. 110 * 111 */ 112 113 int ptyfs_lookup (void *); 114 #define ptyfs_create genfs_eopnotsupp 115 #define ptyfs_mknod genfs_eopnotsupp 116 int ptyfs_open (void *); 117 int ptyfs_close (void *); 118 int ptyfs_access (void *); 119 int ptyfs_getattr (void *); 120 int ptyfs_setattr (void *); 121 int ptyfs_read (void *); 122 int ptyfs_write (void *); 123 #define ptyfs_fcntl genfs_fcntl 124 int ptyfs_ioctl (void *); 125 int ptyfs_poll (void *); 126 int ptyfs_kqfilter (void *); 127 #define ptyfs_revoke genfs_revoke 128 #define ptyfs_mmap genfs_eopnotsupp 129 #define ptyfs_fsync genfs_nullop 130 #define ptyfs_seek genfs_nullop 131 #define ptyfs_remove genfs_eopnotsupp 132 #define ptyfs_link genfs_abortop 133 #define ptyfs_rename genfs_eopnotsupp 134 #define ptyfs_mkdir genfs_eopnotsupp 135 #define ptyfs_rmdir genfs_eopnotsupp 136 #define ptyfs_symlink genfs_abortop 137 int ptyfs_readdir (void *); 138 #define ptyfs_readlink genfs_eopnotsupp 139 #define ptyfs_abortop genfs_abortop 140 int ptyfs_reclaim (void *); 141 #define ptyfs_lock genfs_lock 142 #define ptyfs_unlock genfs_unlock 143 #define ptyfs_bmap genfs_badop 144 #define ptyfs_strategy genfs_badop 145 int ptyfs_print (void *); 146 int ptyfs_pathconf (void *); 147 #define ptyfs_islocked genfs_islocked 148 #define ptyfs_advlock genfs_einval 149 #define ptyfs_blkatoff genfs_eopnotsupp 150 #define ptyfs_valloc genfs_eopnotsupp 151 #define ptyfs_vfree genfs_nullop 152 #define ptyfs_truncate genfs_eopnotsupp 153 int ptyfs_update (void *); 154 #define ptyfs_bwrite genfs_eopnotsupp 155 #define ptyfs_putpages genfs_null_putpages 156 157 static int ptyfs_chown(struct vnode *, uid_t, gid_t, struct ucred *, 158 struct proc *); 159 static int ptyfs_chmod(struct vnode *, mode_t, struct ucred *, struct proc *); 160 static void ptyfs_itimes(struct ptyfsnode *, const struct timespec *, 161 const struct timespec *, const struct timespec *); 162 static int atoi(const char *, size_t); 163 164 extern const struct cdevsw pts_cdevsw, ptc_cdevsw; 165 166 /* 167 * ptyfs vnode operations. 168 */ 169 int (**ptyfs_vnodeop_p)(void *); 170 const struct vnodeopv_entry_desc ptyfs_vnodeop_entries[] = { 171 { &vop_default_desc, vn_default_error }, 172 { &vop_lookup_desc, ptyfs_lookup }, /* lookup */ 173 { &vop_create_desc, ptyfs_create }, /* create */ 174 { &vop_mknod_desc, ptyfs_mknod }, /* mknod */ 175 { &vop_open_desc, ptyfs_open }, /* open */ 176 { &vop_close_desc, ptyfs_close }, /* close */ 177 { &vop_access_desc, ptyfs_access }, /* access */ 178 { &vop_getattr_desc, ptyfs_getattr }, /* getattr */ 179 { &vop_setattr_desc, ptyfs_setattr }, /* setattr */ 180 { &vop_read_desc, ptyfs_read }, /* read */ 181 { &vop_write_desc, ptyfs_write }, /* write */ 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, spec_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_blkatoff_desc, ptyfs_blkatoff }, /* blkatoff */ 210 { &vop_valloc_desc, ptyfs_valloc }, /* valloc */ 211 { &vop_vfree_desc, ptyfs_vfree }, /* vfree */ 212 { &vop_truncate_desc, ptyfs_truncate }, /* truncate */ 213 { &vop_update_desc, ptyfs_update }, /* update */ 214 { &vop_bwrite_desc, ptyfs_bwrite }, /* bwrite */ 215 { &vop_putpages_desc, ptyfs_putpages }, /* putpages */ 216 { NULL, NULL } 217 }; 218 const struct vnodeopv_desc ptyfs_vnodeop_opv_desc = 219 { &ptyfs_vnodeop_p, ptyfs_vnodeop_entries }; 220 221 /* 222 * _reclaim is called when getnewvnode() 223 * wants to make use of an entry on the vnode 224 * free list. at this time the filesystem needs 225 * to free any private data and remove the node 226 * from any private lists. 227 */ 228 int 229 ptyfs_reclaim(void *v) 230 { 231 struct vop_reclaim_args /* { 232 struct vnode *a_vp; 233 } */ *ap = v; 234 return ptyfs_freevp(ap->a_vp); 235 } 236 237 /* 238 * Return POSIX pathconf information applicable to special devices. 239 */ 240 int 241 ptyfs_pathconf(void *v) 242 { 243 struct vop_pathconf_args /* { 244 struct vnode *a_vp; 245 int a_name; 246 register_t *a_retval; 247 } */ *ap = v; 248 249 switch (ap->a_name) { 250 case _PC_LINK_MAX: 251 *ap->a_retval = LINK_MAX; 252 return 0; 253 case _PC_MAX_CANON: 254 *ap->a_retval = MAX_CANON; 255 return 0; 256 case _PC_MAX_INPUT: 257 *ap->a_retval = MAX_INPUT; 258 return 0; 259 case _PC_PIPE_BUF: 260 *ap->a_retval = PIPE_BUF; 261 return 0; 262 case _PC_CHOWN_RESTRICTED: 263 *ap->a_retval = 1; 264 return 0; 265 case _PC_VDISABLE: 266 *ap->a_retval = _POSIX_VDISABLE; 267 return 0; 268 case _PC_SYNC_IO: 269 *ap->a_retval = 1; 270 return 0; 271 default: 272 return EINVAL; 273 } 274 } 275 276 /* 277 * _print is used for debugging. 278 * just print a readable description 279 * of (vp). 280 */ 281 int 282 ptyfs_print(void *v) 283 { 284 struct vop_print_args /* { 285 struct vnode *a_vp; 286 } */ *ap = v; 287 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 288 289 printf("tag VT_PTYFS, type %d, pty %d\n", 290 ptyfs->ptyfs_type, ptyfs->ptyfs_pty); 291 return 0; 292 } 293 294 /* 295 * Invent attributes for ptyfsnode (vp) and store 296 * them in (vap). 297 * Directories lengths are returned as zero since 298 * any real length would require the genuine size 299 * to be computed, and nothing cares anyway. 300 * 301 * this is relatively minimal for ptyfs. 302 */ 303 int 304 ptyfs_getattr(void *v) 305 { 306 struct vop_getattr_args /* { 307 struct vnode *a_vp; 308 struct vattr *a_vap; 309 struct ucred *a_cred; 310 struct proc *a_p; 311 } */ *ap = v; 312 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 313 struct vattr *vap = ap->a_vap; 314 315 ptyfs_itimes(ptyfs, NULL, NULL, NULL); 316 317 /* start by zeroing out the attributes */ 318 VATTR_NULL(vap); 319 320 /* next do all the common fields */ 321 vap->va_type = ap->a_vp->v_type; 322 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsidx.__fsid_val[0]; 323 vap->va_fileid = ptyfs->ptyfs_fileno; 324 vap->va_gen = 0; 325 vap->va_flags = 0; 326 vap->va_nlink = 1; 327 vap->va_blocksize = PAGE_SIZE; 328 329 vap->va_atime = ptyfs->ptyfs_atime; 330 vap->va_mtime = ptyfs->ptyfs_mtime; 331 vap->va_ctime = ptyfs->ptyfs_ctime; 332 vap->va_birthtime = ptyfs->ptyfs_birthtime; 333 vap->va_mode = ptyfs->ptyfs_mode; 334 vap->va_flags = ptyfs->ptyfs_flags; 335 vap->va_uid = ptyfs->ptyfs_uid; 336 vap->va_gid = ptyfs->ptyfs_gid; 337 338 switch (ptyfs->ptyfs_type) { 339 case PTYFSpts: 340 case PTYFSptc: 341 if (pty_isfree(ptyfs->ptyfs_pty, 1)) 342 return ENOENT; 343 vap->va_bytes = vap->va_size = 0; 344 vap->va_rdev = ap->a_vp->v_rdev; 345 break; 346 case PTYFSroot: 347 vap->va_rdev = 0; 348 vap->va_bytes = vap->va_size = DEV_BSIZE; 349 break; 350 351 default: 352 return EOPNOTSUPP; 353 } 354 355 return 0; 356 } 357 358 /*ARGSUSED*/ 359 int 360 ptyfs_setattr(void *v) 361 { 362 struct vop_setattr_args /* { 363 struct vnodeop_desc *a_desc; 364 struct vnode *a_vp; 365 struct vattr *a_vap; 366 struct ucred *a_cred; 367 struct proc *a_p; 368 } */ *ap = v; 369 struct vnode *vp = ap->a_vp; 370 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 371 struct vattr *vap = ap->a_vap; 372 struct ucred *cred = ap->a_cred; 373 struct proc *p = ap->a_p; 374 int error; 375 376 if (vap->va_size != VNOVAL) { 377 switch (ptyfs->ptyfs_type) { 378 case PTYFSroot: 379 return EISDIR; 380 case PTYFSpts: 381 case PTYFSptc: 382 break; 383 default: 384 return EINVAL; 385 } 386 } 387 388 if (vap->va_flags != VNOVAL) { 389 if (vp->v_mount->mnt_flag & MNT_RDONLY) 390 return EROFS; 391 if (cred->cr_uid != ptyfs->ptyfs_uid && 392 (error = suser(cred, &p->p_acflag)) != 0) 393 return error; 394 if (cred->cr_uid == 0) { 395 if ((ptyfs->ptyfs_flags & (SF_IMMUTABLE | SF_APPEND)) && 396 securelevel > 0) 397 return EPERM; 398 /* Snapshot flag cannot be set or cleared */ 399 if ((vap->va_flags & SF_SNAPSHOT) != 400 (ptyfs->ptyfs_flags & SF_SNAPSHOT)) 401 return EPERM; 402 ptyfs->ptyfs_flags = vap->va_flags; 403 } else { 404 if ((ptyfs->ptyfs_flags & (SF_IMMUTABLE | SF_APPEND)) || 405 (vap->va_flags & UF_SETTABLE) != vap->va_flags) 406 return EPERM; 407 if ((ptyfs->ptyfs_flags & SF_SETTABLE) != 408 (vap->va_flags & SF_SETTABLE)) 409 return EPERM; 410 ptyfs->ptyfs_flags &= SF_SETTABLE; 411 ptyfs->ptyfs_flags |= (vap->va_flags & UF_SETTABLE); 412 } 413 ptyfs->ptyfs_flag |= PTYFS_CHANGE; 414 if (vap->va_flags & (IMMUTABLE | APPEND)) 415 return 0; 416 } 417 if (ptyfs->ptyfs_flags & (IMMUTABLE | APPEND)) 418 return EPERM; 419 /* 420 * Go through the fields and update iff not VNOVAL. 421 */ 422 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { 423 if (vp->v_mount->mnt_flag & MNT_RDONLY) 424 return EROFS; 425 if (ptyfs->ptyfs_type == PTYFSroot) 426 return EPERM; 427 error = ptyfs_chown(vp, vap->va_uid, vap->va_gid, cred, p); 428 if (error) 429 return error; 430 } 431 432 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL || 433 vap->va_birthtime.tv_sec != VNOVAL) { 434 if (vp->v_mount->mnt_flag & MNT_RDONLY) 435 return EROFS; 436 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0) 437 return EPERM; 438 if (cred->cr_uid != ptyfs->ptyfs_uid && 439 (error = suser(cred, &p->p_acflag)) && 440 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || 441 (error = VOP_ACCESS(vp, VWRITE, cred, p)) != 0)) 442 return (error); 443 if (vap->va_atime.tv_sec != VNOVAL) 444 if (!(vp->v_mount->mnt_flag & MNT_NOATIME)) 445 ptyfs->ptyfs_flag |= PTYFS_ACCESS; 446 if (vap->va_mtime.tv_sec != VNOVAL) 447 ptyfs->ptyfs_flag |= PTYFS_CHANGE | PTYFS_MODIFY; 448 if (vap->va_birthtime.tv_sec != VNOVAL) 449 ptyfs->ptyfs_birthtime = vap->va_birthtime; 450 ptyfs->ptyfs_flag |= PTYFS_CHANGE; 451 error = VOP_UPDATE(vp, &vap->va_atime, &vap->va_mtime, 0); 452 if (error) 453 return error; 454 } 455 if (vap->va_mode != (mode_t)VNOVAL) { 456 if (vp->v_mount->mnt_flag & MNT_RDONLY) 457 return EROFS; 458 if (ptyfs->ptyfs_type == PTYFSroot) 459 return EPERM; 460 if ((ptyfs->ptyfs_flags & SF_SNAPSHOT) != 0 && 461 (vap->va_mode & 462 (S_IXUSR|S_IWUSR|S_IXGRP|S_IWGRP|S_IXOTH|S_IWOTH))) 463 return EPERM; 464 error = ptyfs_chmod(vp, vap->va_mode, cred, p); 465 if (error) 466 return error; 467 } 468 VN_KNOTE(vp, NOTE_ATTRIB); 469 return 0; 470 } 471 472 /* 473 * Change the mode on a file. 474 * Inode must be locked before calling. 475 */ 476 static int 477 ptyfs_chmod(struct vnode *vp, mode_t mode, struct ucred *cred, struct proc *p) 478 { 479 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 480 int error; 481 482 if (cred->cr_uid != ptyfs->ptyfs_uid && 483 (error = suser(cred, &p->p_acflag)) != 0) 484 return error; 485 ptyfs->ptyfs_mode &= ~ALLPERMS; 486 ptyfs->ptyfs_mode |= (mode & ALLPERMS); 487 return 0; 488 } 489 490 /* 491 * Perform chown operation on inode ip; 492 * inode must be locked prior to call. 493 */ 494 static int 495 ptyfs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred, 496 struct proc *p) 497 { 498 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 499 int error; 500 501 if (uid == (uid_t)VNOVAL) 502 uid = ptyfs->ptyfs_uid; 503 if (gid == (gid_t)VNOVAL) 504 gid = ptyfs->ptyfs_gid; 505 /* 506 * If we don't own the file, are trying to change the owner 507 * of the file, or are not a member of the target group, 508 * the caller's credentials must imply super-user privilege 509 * or the call fails. 510 */ 511 if ((cred->cr_uid != ptyfs->ptyfs_uid || uid != ptyfs->ptyfs_uid || 512 (gid != ptyfs->ptyfs_gid && 513 !(cred->cr_gid == gid || groupmember((gid_t)gid, cred)))) && 514 ((error = suser(cred, &p->p_acflag)) != 0)) 515 return error; 516 517 ptyfs->ptyfs_gid = gid; 518 ptyfs->ptyfs_uid = uid; 519 return 0; 520 } 521 522 /* 523 * implement access checking. 524 * 525 * actually, the check for super-user is slightly 526 * broken since it will allow read access to write-only 527 * objects. this doesn't cause any particular trouble 528 * but does mean that the i/o entry points need to check 529 * that the operation really does make sense. 530 */ 531 int 532 ptyfs_access(void *v) 533 { 534 struct vop_access_args /* { 535 struct vnode *a_vp; 536 int a_mode; 537 struct ucred *a_cred; 538 struct proc *a_p; 539 } */ *ap = v; 540 struct vattr va; 541 int error; 542 543 if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred, ap->a_p)) != 0) 544 return error; 545 546 return vaccess(va.va_type, va.va_mode, 547 va.va_uid, va.va_gid, ap->a_mode, ap->a_cred); 548 } 549 550 /* 551 * lookup. this is incredibly complicated in the 552 * general case, however for most pseudo-filesystems 553 * very little needs to be done. 554 * 555 * Locking isn't hard here, just poorly documented. 556 * 557 * If we're looking up ".", just vref the parent & return it. 558 * 559 * If we're looking up "..", unlock the parent, and lock "..". If everything 560 * went ok, and we're on the last component and the caller requested the 561 * parent locked, try to re-lock the parent. We do this to prevent lock 562 * races. 563 * 564 * For anything else, get the needed node. Then unlock the parent if not 565 * the last component or not LOCKPARENT (i.e. if we wouldn't re-lock the 566 * parent in the .. case). 567 * 568 * We try to exit with the parent locked in error cases. 569 */ 570 int 571 ptyfs_lookup(void *v) 572 { 573 struct vop_lookup_args /* { 574 struct vnode * a_dvp; 575 struct vnode ** a_vpp; 576 struct componentname * a_cnp; 577 } */ *ap = v; 578 struct componentname *cnp = ap->a_cnp; 579 struct vnode **vpp = ap->a_vpp; 580 struct vnode *dvp = ap->a_dvp; 581 const char *pname = cnp->cn_nameptr; 582 struct ptyfsnode *ptyfs; 583 int pty, error, wantpunlock; 584 585 *vpp = NULL; 586 cnp->cn_flags &= ~PDIRUNLOCK; 587 588 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 589 return EROFS; 590 591 if (cnp->cn_namelen == 1 && *pname == '.') { 592 *vpp = dvp; 593 VREF(dvp); 594 return 0; 595 } 596 597 wantpunlock = ~cnp->cn_flags & (LOCKPARENT | ISLASTCN); 598 ptyfs = VTOPTYFS(dvp); 599 switch (ptyfs->ptyfs_type) { 600 case PTYFSroot: 601 /* 602 * Shouldn't get here with .. in the root node. 603 */ 604 if (cnp->cn_flags & ISDOTDOT) 605 return EIO; 606 607 pty = atoi(pname, cnp->cn_namelen); 608 609 if (pty < 0 || pty >= npty || pty_isfree(pty, 1)) 610 break; 611 612 error = ptyfs_allocvp(dvp->v_mount, vpp, PTYFSpts, pty, 613 curproc); 614 if (error == 0 && wantpunlock) { 615 VOP_UNLOCK(dvp, 0); 616 cnp->cn_flags |= PDIRUNLOCK; 617 } 618 return error; 619 620 default: 621 return ENOTDIR; 622 } 623 624 return cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS; 625 } 626 627 /* 628 * readdir returns directory entries from ptyfsnode (vp). 629 * 630 * the strategy here with ptyfs is to generate a single 631 * directory entry at a time (struct dirent) and then 632 * copy that out to userland using uiomove. a more efficent 633 * though more complex implementation, would try to minimize 634 * the number of calls to uiomove(). for ptyfs, this is 635 * hardly worth the added code complexity. 636 * 637 * this should just be done through read() 638 */ 639 int 640 ptyfs_readdir(void *v) 641 { 642 struct vop_readdir_args /* { 643 struct vnode *a_vp; 644 struct uio *a_uio; 645 struct ucred *a_cred; 646 int *a_eofflag; 647 off_t **a_cookies; 648 int *a_ncookies; 649 } */ *ap = v; 650 struct uio *uio = ap->a_uio; 651 struct dirent d; 652 struct ptyfsnode *ptyfs; 653 off_t i; 654 int error; 655 off_t *cookies = NULL; 656 int ncookies; 657 struct vnode *vp; 658 int nc = 0; 659 660 vp = ap->a_vp; 661 ptyfs = VTOPTYFS(vp); 662 663 if (uio->uio_resid < UIO_MX) 664 return EINVAL; 665 if (uio->uio_offset < 0) 666 return EINVAL; 667 668 error = 0; 669 i = uio->uio_offset; 670 (void)memset(&d, 0, sizeof(d)); 671 d.d_reclen = UIO_MX; 672 ncookies = uio->uio_resid / UIO_MX; 673 674 switch (ptyfs->ptyfs_type) { 675 case PTYFSroot: /* root */ 676 677 if (i >= npty) 678 return 0; 679 680 if (ap->a_ncookies) { 681 ncookies = min(ncookies, (npty + 2 - i)); 682 cookies = malloc(ncookies * sizeof (off_t), 683 M_TEMP, M_WAITOK); 684 *ap->a_cookies = cookies; 685 } 686 687 for (; i < 2; i++) { 688 switch (i) { 689 case 0: /* `.' */ 690 case 1: /* `..' */ 691 d.d_fileno = PTYFS_FILENO(0, PTYFSroot); 692 d.d_namlen = i + 1; 693 (void)memcpy(d.d_name, "..", d.d_namlen); 694 d.d_name[i + 1] = '\0'; 695 d.d_type = DT_DIR; 696 break; 697 } 698 if ((error = uiomove(&d, UIO_MX, uio)) != 0) 699 break; 700 if (cookies) 701 *cookies++ = i + 1; 702 nc++; 703 } 704 if (error) { 705 ncookies = nc; 706 break; 707 } 708 for (; uio->uio_resid >= UIO_MX && i < npty; i++) { 709 /* check for used ptys */ 710 if (pty_isfree(i - 2, 1)) 711 continue; 712 713 d.d_fileno = PTYFS_FILENO(i - 2, PTYFSpts); 714 d.d_namlen = snprintf(d.d_name, sizeof(d.d_name), 715 "%lld", (long long)(i - 2)); 716 d.d_type = DT_CHR; 717 if ((error = uiomove(&d, UIO_MX, uio)) != 0) 718 break; 719 if (cookies) 720 *cookies++ = i + 1; 721 nc++; 722 } 723 ncookies = nc; 724 break; 725 726 default: 727 error = ENOTDIR; 728 break; 729 } 730 731 if (ap->a_ncookies) { 732 if (error) { 733 if (cookies) 734 free(*ap->a_cookies, M_TEMP); 735 *ap->a_ncookies = 0; 736 *ap->a_cookies = NULL; 737 } else 738 *ap->a_ncookies = ncookies; 739 } 740 uio->uio_offset = i; 741 return error; 742 } 743 744 int 745 ptyfs_open(void *v) 746 { 747 struct vop_open_args /* { 748 struct vnode *a_vp; 749 int a_mode; 750 struct ucred *a_cred; 751 struct proc *a_p; 752 } */ *ap = v; 753 struct vnode *vp = ap->a_vp; 754 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 755 756 ptyfs->ptyfs_flag |= PTYFS_CHANGE|PTYFS_ACCESS; 757 switch (ptyfs->ptyfs_type) { 758 case PTYFSpts: 759 case PTYFSptc: 760 return spec_open(v); 761 case PTYFSroot: 762 return 0; 763 default: 764 return EINVAL; 765 } 766 } 767 768 int 769 ptyfs_close(void *v) 770 { 771 struct vop_close_args /* { 772 struct vnode *a_vp; 773 int a_fflag; 774 struct ucred *a_cred; 775 struct proc *a_p; 776 } */ *ap = v; 777 struct vnode *vp = ap->a_vp; 778 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 779 780 simple_lock(&vp->v_interlock); 781 if (vp->v_usecount > 1) 782 ptyfs_itimes(ptyfs, NULL, NULL, NULL); 783 simple_unlock(&vp->v_interlock); 784 785 switch (ptyfs->ptyfs_type) { 786 case PTYFSpts: 787 case PTYFSptc: 788 return spec_close(v); 789 case PTYFSroot: 790 return 0; 791 default: 792 return EINVAL; 793 } 794 } 795 796 int 797 ptyfs_read(void *v) 798 { 799 struct vop_read_args /* { 800 struct vnode *a_vp; 801 struct uio *a_uio; 802 int a_ioflag; 803 struct ucred *a_cred; 804 } */ *ap = v; 805 struct vnode *vp = ap->a_vp; 806 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 807 int error; 808 809 ptyfs->ptyfs_flag |= PTYFS_ACCESS; 810 switch (ptyfs->ptyfs_type) { 811 case PTYFSpts: 812 VOP_UNLOCK(vp, 0); 813 error = (*pts_cdevsw.d_read)(vp->v_rdev, ap->a_uio, 814 ap->a_ioflag); 815 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 816 return error; 817 case PTYFSptc: 818 VOP_UNLOCK(vp, 0); 819 error = (*ptc_cdevsw.d_read)(vp->v_rdev, ap->a_uio, 820 ap->a_ioflag); 821 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 822 return error; 823 default: 824 return EOPNOTSUPP; 825 } 826 } 827 828 int 829 ptyfs_write(void *v) 830 { 831 struct vop_write_args /* { 832 struct vnode *a_vp; 833 struct uio *a_uio; 834 int a_ioflag; 835 struct ucred *a_cred; 836 } */ *ap = v; 837 int error; 838 struct vnode *vp = ap->a_vp; 839 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 840 841 ptyfs->ptyfs_flag |= PTYFS_MODIFY; 842 switch (ptyfs->ptyfs_type) { 843 case PTYFSpts: 844 VOP_UNLOCK(vp, 0); 845 error = (*pts_cdevsw.d_write)(vp->v_rdev, ap->a_uio, 846 ap->a_ioflag); 847 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 848 return error; 849 case PTYFSptc: 850 VOP_UNLOCK(vp, 0); 851 error = (*ptc_cdevsw.d_write)(vp->v_rdev, ap->a_uio, 852 ap->a_ioflag); 853 vn_lock(vp, LK_RETRY|LK_EXCLUSIVE); 854 return error; 855 default: 856 return EOPNOTSUPP; 857 } 858 } 859 860 int 861 ptyfs_ioctl(void *v) 862 { 863 struct vop_ioctl_args /* { 864 struct vnode *a_vp; 865 u_long a_command; 866 void *a_data; 867 int a_fflag; 868 struct ucred *a_cred; 869 struct proc *a_p; 870 } */ *ap = v; 871 struct vnode *vp = ap->a_vp; 872 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 873 874 switch (ptyfs->ptyfs_type) { 875 case PTYFSpts: 876 return (*pts_cdevsw.d_ioctl)(vp->v_rdev, ap->a_command, 877 ap->a_data, ap->a_fflag, ap->a_p); 878 case PTYFSptc: 879 return (*ptc_cdevsw.d_ioctl)(vp->v_rdev, ap->a_command, 880 ap->a_data, ap->a_fflag, ap->a_p); 881 default: 882 return EOPNOTSUPP; 883 } 884 } 885 886 int 887 ptyfs_poll(void *v) 888 { 889 struct vop_poll_args /* { 890 struct vnode *a_vp; 891 int a_events; 892 struct proc *a_p; 893 } */ *ap = v; 894 struct vnode *vp = ap->a_vp; 895 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 896 897 switch (ptyfs->ptyfs_type) { 898 case PTYFSpts: 899 return (*pts_cdevsw.d_poll)(vp->v_rdev, ap->a_events, ap->a_p); 900 case PTYFSptc: 901 return (*ptc_cdevsw.d_poll)(vp->v_rdev, ap->a_events, ap->a_p); 902 default: 903 return genfs_poll(v); 904 } 905 } 906 907 int 908 ptyfs_kqfilter(void *v) 909 { 910 struct vop_kqfilter_args /* { 911 struct vnode *a_vp; 912 struct knote *a_kn; 913 } */ *ap = v; 914 struct vnode *vp = ap->a_vp; 915 struct ptyfsnode *ptyfs = VTOPTYFS(vp); 916 917 switch (ptyfs->ptyfs_type) { 918 case PTYFSpts: 919 return (*pts_cdevsw.d_kqfilter)(vp->v_rdev, ap->a_kn); 920 case PTYFSptc: 921 return (*ptc_cdevsw.d_kqfilter)(vp->v_rdev, ap->a_kn); 922 default: 923 return genfs_kqfilter(v); 924 } 925 } 926 927 int 928 ptyfs_update(v) 929 void *v; 930 { 931 struct vop_update_args /* { 932 struct vnode *a_vp; 933 struct timespec *a_access; 934 struct timespec *a_modify; 935 int a_flags; 936 } */ *ap = v; 937 struct ptyfsnode *ptyfs = VTOPTYFS(ap->a_vp); 938 939 if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) 940 return 0; 941 942 ptyfs_itimes(ptyfs, ap->a_access, ap->a_modify, NULL); 943 return 0; 944 } 945 946 void 947 ptyfs_itimes(struct ptyfsnode *ptyfs, const struct timespec *acc, 948 const struct timespec *mod, const struct timespec *cre) 949 { 950 struct timespec *ts = NULL, tsb; 951 952 if (ptyfs->ptyfs_flag & (PTYFS_ACCESS|PTYFS_MODIFY)) { 953 if (acc == NULL) 954 acc = ts == NULL ? (ts = nanotime(&tsb)) : ts; 955 ptyfs->ptyfs_atime = *acc; 956 } 957 if (ptyfs->ptyfs_flag & PTYFS_MODIFY) { 958 if (mod == NULL) 959 mod = ts == NULL ? (ts = nanotime(&tsb)) : ts; 960 ptyfs->ptyfs_mtime = *mod; 961 } 962 if (ptyfs->ptyfs_flag & PTYFS_CHANGE) { 963 if (cre == NULL) 964 cre = ts == NULL ? (ts = nanotime(&tsb)) : ts; 965 ptyfs->ptyfs_atime = *cre; 966 } 967 ptyfs->ptyfs_flag &= ~(PTYFS_ACCESS | PTYFS_CHANGE | PTYFS_MODIFY); 968 } 969 970 /* 971 * convert decimal ascii to int 972 */ 973 static int 974 atoi(const char *b, size_t len) 975 { 976 int p = 0; 977 978 while (len--) { 979 char c = *b++; 980 if (c < '0' || c > '9') 981 return -1; 982 p = 10 * p + (c - '0'); 983 } 984 985 return p; 986 } 987
Indexes created Fri Sep 26 20:09:58 GMT 2025