sys/kern/vfs_syscalls.c

   1 /*
   2  * Copyright (c) 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * (c) UNIX System Laboratories, Inc.
   5  * All or some portions of this file are derived from material licensed
   6  * to the University of California by American Telephone and Telegraph
   7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
   8  * the permission of UNIX System Laboratories, Inc.
   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. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)vfs_syscalls.c      8.13 (Berkeley) 4/15/94
  39  * $FreeBSD: src/sys/kern/vfs_syscalls.c,v 1.151.2.18 2003/04/04 20:35:58 tegge Exp $
  40  * $DragonFly: src/sys/kern/vfs_syscalls.c,v 1.135 2008/11/11 00:55:49 pavalos Exp $
  41  */
  42
  43 #include <sys/param.h>
  44 #include <sys/systm.h>
  45 #include <sys/buf.h>
  46 #include <sys/conf.h>
  47 #include <sys/sysent.h>
  48 #include <sys/malloc.h>
  49 #include <sys/mount.h>
  50 #include <sys/mountctl.h>
  51 #include <sys/sysproto.h>
  52 #include <sys/filedesc.h>
  53 #include <sys/kernel.h>
  54 #include <sys/fcntl.h>
  55 #include <sys/file.h>
  56 #include <sys/linker.h>
  57 #include <sys/stat.h>
  58 #include <sys/unistd.h>
  59 #include <sys/vnode.h>
  60 #include <sys/proc.h>
  61 #include <sys/priv.h>
  62 #include <sys/jail.h>
  63 #include <sys/namei.h>
  64 #include <sys/nlookup.h>
  65 #include <sys/dirent.h>
  66 #include <sys/extattr.h>
  67 #include <sys/spinlock.h>
  68 #include <sys/kern_syscall.h>
  69 #include <sys/objcache.h>
  70 #include <sys/sysctl.h>
  71
  72 #include <sys/buf2.h>
  73 #include <sys/file2.h>
  74 #include <sys/spinlock2.h>
  75
  76 #include <vm/vm.h>
  77 #include <vm/vm_object.h>
  78 #include <vm/vm_page.h>
  79
  80 #include <machine/limits.h>
  81 #include <machine/stdarg.h>
  82
  83 #include <vfs/union/union.h>
  84
  85 static void mount_warning(struct mount *mp, const char *ctl, ...);
  86 static int mount_path(struct proc *p, struct mount *mp, char **rb, char **fb);
  87 static int checkvp_chdir (struct vnode *vn, struct thread *td);
  88 static void checkdirs (struct nchandle *old_nch, struct nchandle *new_nch);
  89 static int chroot_refuse_vdir_fds (struct filedesc *fdp);
  90 static int chroot_visible_mnt(struct mount *mp, struct proc *p);
  91 static int getutimes (const struct timeval *, struct timespec *);
  92 static int setfown (struct vnode *, uid_t, gid_t);
  93 static int setfmode (struct vnode *, int);
  94 static int setfflags (struct vnode *, int);
  95 static int setutimes (struct vnode *, struct vattr *,
  96                         const struct timespec *, int);
  97 static int      usermount = 0;  /* if 1, non-root can mount fs. */
  98
  99 int (*union_dircheckp) (struct thread *, struct vnode **, struct file *);
 100
 101 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, "");
 102
 103 /*
 104  * Virtual File System System Calls
 105  */
 106
 107 /*
 108  * Mount a file system.
 109  */
 110 /*
 111  * mount_args(char *type, char *path, int flags, caddr_t data)
 112  */
 113 /* ARGSUSED */
 114 int
 115 sys_mount(struct mount_args *uap)
 116 {
 117         struct thread *td = curthread;
 118         struct proc *p = td->td_proc;
 119         struct vnode *vp;
 120         struct nchandle nch;
 121         struct mount *mp;
 122         struct vfsconf *vfsp;
 123         int error, flag = 0, flag2 = 0;
 124         int hasmount;
 125         struct vattr va;
 126         struct nlookupdata nd;
 127         char fstypename[MFSNAMELEN];
 128         struct ucred *cred = p->p_ucred;
 129
 130         KKASSERT(p);
 131         if (jailed(cred))
 132                 return (EPERM);
 133         if (usermount == 0 && (error = priv_check(td, PRIV_ROOT)))
 134                 return (error);
 135         /*
 136          * Do not allow NFS export by non-root users.
 137          */
 138         if (uap->flags & MNT_EXPORTED) {
 139                 error = priv_check(td, PRIV_ROOT);
 140                 if (error)
 141                         return (error);
 142         }
 143         /*
 144          * Silently enforce MNT_NOSUID and MNT_NODEV for non-root users
 145          */
 146         if (priv_check(td, PRIV_ROOT))
 147                 uap->flags |= MNT_NOSUID | MNT_NODEV;
 148
 149         /*
 150          * Lookup the requested path and extract the nch and vnode.
 151          */
 152         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
 153         if (error == 0) {
 154                 if ((error = nlookup(&nd)) == 0) {
 155                         if (nd.nl_nch.ncp->nc_vp == NULL)
 156                                 error = ENOENT;
 157                 }
 158         }
 159         if (error) {
 160                 nlookup_done(&nd);
 161                 return (error);
 162         }
 163
 164         /*
 165          * Extract the locked+refd ncp and cleanup the nd structure
 166          */
 167         nch = nd.nl_nch;
 168         cache_zero(&nd.nl_nch);
 169         nlookup_done(&nd);
 170
 171         if ((nch.ncp->nc_flag & NCF_ISMOUNTPT) && cache_findmount(&nch))
 172                 hasmount = 1;
 173         else
 174                 hasmount = 0;
 175
 176
 177         /*
 178          * now we have the locked ref'd nch and unreferenced vnode.
 179          */
 180         vp = nch.ncp->nc_vp;
 181         if ((error = vget(vp, LK_EXCLUSIVE)) != 0) {
 182                 cache_put(&nch);
 183                 return (error);
 184         }
 185         cache_unlock(&nch);
 186
 187         /*
 188          * Now we have an unlocked ref'd nch and a locked ref'd vp
 189          */
 190         if (uap->flags & MNT_UPDATE) {
 191                 if ((vp->v_flag & (VROOT|VPFSROOT)) == 0) {
 192                         cache_drop(&nch);
 193                         vput(vp);
 194                         return (EINVAL);
 195                 }
 196                 mp = vp->v_mount;
 197                 flag = mp->mnt_flag;
 198                 flag2 = mp->mnt_kern_flag;
 199                 /*
 200                  * We only allow the filesystem to be reloaded if it
 201                  * is currently mounted read-only.
 202                  */
 203                 if ((uap->flags & MNT_RELOAD) &&
 204                     ((mp->mnt_flag & MNT_RDONLY) == 0)) {
 205                         cache_drop(&nch);
 206                         vput(vp);
 207                         return (EOPNOTSUPP);    /* Needs translation */
 208                 }
 209                 /*
 210                  * Only root, or the user that did the original mount is
 211                  * permitted to update it.
 212                  */
 213                 if (mp->mnt_stat.f_owner != cred->cr_uid &&
 214                     (error = priv_check(td, PRIV_ROOT))) {
 215                         cache_drop(&nch);
 216                         vput(vp);
 217                         return (error);
 218                 }
 219                 if (vfs_busy(mp, LK_NOWAIT)) {
 220                         cache_drop(&nch);
 221                         vput(vp);
 222                         return (EBUSY);
 223                 }
 224                 if ((vp->v_flag & VMOUNT) != 0 || hasmount) {
 225                         cache_drop(&nch);
 226                         vfs_unbusy(mp);
 227                         vput(vp);
 228                         return (EBUSY);
 229                 }
 230                 vp->v_flag |= VMOUNT;
 231                 mp->mnt_flag |=
 232                     uap->flags & (MNT_RELOAD | MNT_FORCE | MNT_UPDATE);
 233                 vn_unlock(vp);
 234                 goto update;
 235         }
 236         /*
 237          * If the user is not root, ensure that they own the directory
 238          * onto which we are attempting to mount.
 239          */
 240         if ((error = VOP_GETATTR(vp, &va)) ||
 241             (va.va_uid != cred->cr_uid && (error = priv_check(td, PRIV_ROOT)))) {
 242                 cache_drop(&nch);
 243                 vput(vp);
 244                 return (error);
 245         }
 246         if ((error = vinvalbuf(vp, V_SAVE, 0, 0)) != 0) {
 247                 cache_drop(&nch);
 248                 vput(vp);
 249                 return (error);
 250         }
 251         if (vp->v_type != VDIR) {
 252                 cache_drop(&nch);
 253                 vput(vp);
 254                 return (ENOTDIR);
 255         }
 256         if (vp->v_mount->mnt_kern_flag & MNTK_NOSTKMNT) {
 257                 cache_drop(&nch);
 258                 vput(vp);
 259                 return (EPERM);
 260         }
 261         if ((error = copyinstr(uap->type, fstypename, MFSNAMELEN, NULL)) != 0) {
 262                 cache_drop(&nch);
 263                 vput(vp);
 264                 return (error);
 265         }
 266         vfsp = vfsconf_find_by_name(fstypename);
 267         if (vfsp == NULL) {
 268                 linker_file_t lf;
 269
 270                 /* Only load modules for root (very important!) */
 271                 if ((error = priv_check(td, PRIV_ROOT)) != 0) {
 272                         cache_drop(&nch);
 273                         vput(vp);
 274                         return error;
 275                 }
 276                 error = linker_load_file(fstypename, &lf, 0);
 277                 if (error || lf == NULL) {
 278                         cache_drop(&nch);
 279                         vput(vp);
 280                         if (lf == NULL)
 281                                 error = ENODEV;
 282                         return error;
 283                 }
 284                 lf->userrefs++;
 285                 /* lookup again, see if the VFS was loaded */
 286                 vfsp = vfsconf_find_by_name(fstypename);
 287                 if (vfsp == NULL) {
 288                         lf->userrefs--;
 289                         linker_file_unload(lf);
 290                         cache_drop(&nch);
 291                         vput(vp);
 292                         return (ENODEV);
 293                 }
 294         }
 295         if ((vp->v_flag & VMOUNT) != 0 || hasmount) {
 296                 cache_drop(&nch);
 297                 vput(vp);
 298                 return (EBUSY);
 299         }
 300         vp->v_flag |= VMOUNT;
 301
 302         /*
 303          * Allocate and initialize the filesystem.
 304          */
 305         mp = kmalloc(sizeof(struct mount), M_MOUNT, M_ZERO|M_WAITOK);
 306         TAILQ_INIT(&mp->mnt_nvnodelist);
 307         TAILQ_INIT(&mp->mnt_reservedvnlist);
 308         TAILQ_INIT(&mp->mnt_jlist);
 309         mp->mnt_nvnodelistsize = 0;
 310         lockinit(&mp->mnt_lock, "vfslock", 0, 0);
 311         vfs_busy(mp, LK_NOWAIT);
 312         mp->mnt_op = vfsp->vfc_vfsops;
 313         mp->mnt_vfc = vfsp;
 314         vfsp->vfc_refcount++;
 315         mp->mnt_stat.f_type = vfsp->vfc_typenum;
 316         mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK;
 317         strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN);
 318         mp->mnt_stat.f_owner = cred->cr_uid;
 319         mp->mnt_iosize_max = DFLTPHYS;
 320         vn_unlock(vp);
 321 update:
 322         /*
 323          * Set the mount level flags.
 324          */
 325         if (uap->flags & MNT_RDONLY)
 326                 mp->mnt_flag |= MNT_RDONLY;
 327         else if (mp->mnt_flag & MNT_RDONLY)
 328                 mp->mnt_kern_flag |= MNTK_WANTRDWR;
 329         mp->mnt_flag &=~ (MNT_NOSUID | MNT_NOEXEC | MNT_NODEV |
 330             MNT_SYNCHRONOUS | MNT_UNION | MNT_ASYNC | MNT_NOATIME |
 331             MNT_NOSYMFOLLOW | MNT_IGNORE |
 332             MNT_NOCLUSTERR | MNT_NOCLUSTERW | MNT_SUIDDIR);
 333         mp->mnt_flag |= uap->flags & (MNT_NOSUID | MNT_NOEXEC |
 334             MNT_NODEV | MNT_SYNCHRONOUS | MNT_UNION | MNT_ASYNC | MNT_FORCE |
 335             MNT_NOSYMFOLLOW | MNT_IGNORE |
 336             MNT_NOATIME | MNT_NOCLUSTERR | MNT_NOCLUSTERW | MNT_SUIDDIR);
 337         /*
 338          * Mount the filesystem.
 339          * XXX The final recipients of VFS_MOUNT just overwrite the ndp they
 340          * get.
 341          */
 342         error = VFS_MOUNT(mp, uap->path, uap->data, cred);
 343         if (mp->mnt_flag & MNT_UPDATE) {
 344                 if (mp->mnt_kern_flag & MNTK_WANTRDWR)
 345                         mp->mnt_flag &= ~MNT_RDONLY;
 346                 mp->mnt_flag &=~ (MNT_UPDATE | MNT_RELOAD | MNT_FORCE);
 347                 mp->mnt_kern_flag &=~ MNTK_WANTRDWR;
 348                 if (error) {
 349                         mp->mnt_flag = flag;
 350                         mp->mnt_kern_flag = flag2;
 351                 }
 352                 vfs_unbusy(mp);
 353                 vp->v_flag &= ~VMOUNT;
 354                 vrele(vp);
 355                 cache_drop(&nch);
 356                 return (error);
 357         }
 358         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
 359         /*
 360          * Put the new filesystem on the mount list after root.  The mount
 361          * point gets its own mnt_ncmountpt (unless the VFS already set one
 362          * up) which represents the root of the mount.  The lookup code
 363          * detects the mount point going forward and checks the root of
 364          * the mount going backwards.
 365          *
 366          * It is not necessary to invalidate or purge the vnode underneath
 367          * because elements under the mount will be given their own glue
 368          * namecache record.
 369          */
 370         if (!error) {
 371                 if (mp->mnt_ncmountpt.ncp == NULL) {
 372                         /*
 373                          * allocate, then unlock, but leave the ref intact
 374                          */
 375                         cache_allocroot(&mp->mnt_ncmountpt, mp, NULL);
 376                         cache_unlock(&mp->mnt_ncmountpt);
 377                 }
 378                 mp->mnt_ncmounton = nch;                /* inherits ref */
 379                 nch.ncp->nc_flag |= NCF_ISMOUNTPT;
 380
 381                 /* XXX get the root of the fs and cache_setvp(mnt_ncmountpt...) */
 382                 vp->v_flag &= ~VMOUNT;
 383                 mountlist_insert(mp, MNTINS_LAST);
 384                 vn_unlock(vp);
 385                 checkdirs(&mp->mnt_ncmounton, &mp->mnt_ncmountpt);
 386                 error = vfs_allocate_syncvnode(mp);
 387                 vfs_unbusy(mp);
 388                 error = VFS_START(mp, 0);
 389                 vrele(vp);
 390         } else {
 391                 vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_coherency_ops);
 392                 vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_journal_ops);
 393                 vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_norm_ops);
 394                 vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_spec_ops);
 395                 vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_fifo_ops);
 396                 vp->v_flag &= ~VMOUNT;
 397                 mp->mnt_vfc->vfc_refcount--;
 398                 vfs_unbusy(mp);
 399                 kfree(mp, M_MOUNT);
 400                 cache_drop(&nch);
 401                 vput(vp);
 402         }
 403         return (error);
 404 }
 405
 406 /*
 407  * Scan all active processes to see if any of them have a current
 408  * or root directory onto which the new filesystem has just been
 409  * mounted. If so, replace them with the new mount point.
 410  *
 411  * The passed ncp is ref'd and locked (from the mount code) and
 412  * must be associated with the vnode representing the root of the
 413  * mount point.
 414  */
 415 struct checkdirs_info {
 416         struct nchandle old_nch;
 417         struct nchandle new_nch;
 418         struct vnode *old_vp;
 419         struct vnode *new_vp;
 420 };
 421
 422 static int checkdirs_callback(struct proc *p, void *data);
 423
 424 static void
 425 checkdirs(struct nchandle *old_nch, struct nchandle *new_nch)
 426 {
 427         struct checkdirs_info info;
 428         struct vnode *olddp;
 429         struct vnode *newdp;
 430         struct mount *mp;
 431
 432         /*
 433          * If the old mount point's vnode has a usecount of 1, it is not
 434          * being held as a descriptor anywhere.
 435          */
 436         olddp = old_nch->ncp->nc_vp;
 437         if (olddp == NULL || olddp->v_sysref.refcnt == 1)
 438                 return;
 439
 440         /*
 441          * Force the root vnode of the new mount point to be resolved
 442          * so we can update any matching processes.
 443          */
 444         mp = new_nch->mount;
 445         if (VFS_ROOT(mp, &newdp))
 446                 panic("mount: lost mount");
 447         cache_setunresolved(new_nch);
 448         cache_setvp(new_nch, newdp);
 449
 450         /*
 451          * Special handling of the root node
 452          */
 453         if (rootvnode == olddp) {
 454                 vref(newdp);
 455                 vfs_cache_setroot(newdp, cache_hold(new_nch));
 456         }
 457
 458         /*
 459          * Pass newdp separately so the callback does not have to access
 460          * it via new_nch->ncp->nc_vp.
 461          */
 462         info.old_nch = *old_nch;
 463         info.new_nch = *new_nch;
 464         info.new_vp = newdp;
 465         allproc_scan(checkdirs_callback, &info);
 466         vput(newdp);
 467 }
 468
 469 /*
 470  * NOTE: callback is not MP safe because the scanned process's filedesc
 471  * structure can be ripped out from under us, amoung other things.
 472  */
 473 static int
 474 checkdirs_callback(struct proc *p, void *data)
 475 {
 476         struct checkdirs_info *info = data;
 477         struct filedesc *fdp;
 478         struct nchandle ncdrop1;
 479         struct nchandle ncdrop2;
 480         struct vnode *vprele1;
 481         struct vnode *vprele2;
 482
 483         if ((fdp = p->p_fd) != NULL) {
 484                 cache_zero(&ncdrop1);
 485                 cache_zero(&ncdrop2);
 486                 vprele1 = NULL;
 487                 vprele2 = NULL;
 488
 489                 /*
 490                  * MPUNSAFE - XXX fdp can be pulled out from under a
 491                  * foreign process.
 492                  *
 493                  * A shared filedesc is ok, we don't have to copy it
 494                  * because we are making this change globally.
 495                  */
 496                 spin_lock_wr(&fdp->fd_spin);
 497                 if (fdp->fd_ncdir.mount == info->old_nch.mount &&
 498                     fdp->fd_ncdir.ncp == info->old_nch.ncp) {
 499                         vprele1 = fdp->fd_cdir;
 500                         vref(info->new_vp);
 501                         fdp->fd_cdir = info->new_vp;
 502                         ncdrop1 = fdp->fd_ncdir;
 503                         cache_copy(&info->new_nch, &fdp->fd_ncdir);
 504                 }
 505                 if (fdp->fd_nrdir.mount == info->old_nch.mount &&
 506                     fdp->fd_nrdir.ncp == info->old_nch.ncp) {
 507                         vprele2 = fdp->fd_rdir;
 508                         vref(info->new_vp);
 509                         fdp->fd_rdir = info->new_vp;
 510                         ncdrop2 = fdp->fd_nrdir;
 511                         cache_copy(&info->new_nch, &fdp->fd_nrdir);
 512                 }
 513                 spin_unlock_wr(&fdp->fd_spin);
 514                 if (ncdrop1.ncp)
 515                         cache_drop(&ncdrop1);
 516                 if (ncdrop2.ncp)
 517                         cache_drop(&ncdrop2);
 518                 if (vprele1)
 519                         vrele(vprele1);
 520                 if (vprele2)
 521                         vrele(vprele2);
 522         }
 523         return(0);
 524 }
 525
 526 /*
 527  * Unmount a file system.
 528  *
 529  * Note: unmount takes a path to the vnode mounted on as argument,
 530  * not special file (as before).
 531  */
 532 /*
 533  * umount_args(char *path, int flags)
 534  */
 535 /* ARGSUSED */
 536 int
 537 sys_unmount(struct unmount_args *uap)
 538 {
 539         struct thread *td = curthread;
 540         struct proc *p = td->td_proc;
 541         struct mount *mp = NULL;
 542         int error;
 543         struct nlookupdata nd;
 544
 545         KKASSERT(p);
 546         if (p->p_ucred->cr_prison != NULL)
 547                 return (EPERM);
 548         if (usermount == 0 && (error = priv_check(td, PRIV_ROOT)))
 549                 return (error);
 550
 551         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
 552         if (error == 0)
 553                 error = nlookup(&nd);
 554         if (error)
 555                 goto out;
 556
 557         mp = nd.nl_nch.mount;
 558
 559         /*
 560          * Only root, or the user that did the original mount is
 561          * permitted to unmount this filesystem.
 562          */
 563         if ((mp->mnt_stat.f_owner != p->p_ucred->cr_uid) &&
 564             (error = priv_check(td, PRIV_ROOT)))
 565                 goto out;
 566
 567         /*
 568          * Don't allow unmounting the root file system.
 569          */
 570         if (mp->mnt_flag & MNT_ROOTFS) {
 571                 error = EINVAL;
 572                 goto out;
 573         }
 574
 575         /*
 576          * Must be the root of the filesystem
 577          */
 578         if (nd.nl_nch.ncp != mp->mnt_ncmountpt.ncp) {
 579                 error = EINVAL;
 580                 goto out;
 581         }
 582
 583 out:
 584         nlookup_done(&nd);
 585         if (error)
 586                 return (error);
 587         return (dounmount(mp, uap->flags));
 588 }
 589
 590 /*
 591  * Do the actual file system unmount.
 592  */
 593 static int
 594 dounmount_interlock(struct mount *mp)
 595 {
 596         if (mp->mnt_kern_flag & MNTK_UNMOUNT)
 597                 return (EBUSY);
 598         mp->mnt_kern_flag |= MNTK_UNMOUNT;
 599         return(0);
 600 }
 601
 602 int
 603 dounmount(struct mount *mp, int flags)
 604 {
 605         struct namecache *ncp;
 606         struct nchandle nch;
 607         struct vnode *vp;
 608         int error;
 609         int async_flag;
 610         int lflags;
 611         int freeok = 1;
 612
 613         /*
 614          * Exclusive access for unmounting purposes
 615          */
 616         if ((error = mountlist_interlock(dounmount_interlock, mp)) != 0)
 617                 return (error);
 618
 619         /*
 620          * Allow filesystems to detect that a forced unmount is in progress.
 621          */
 622         if (flags & MNT_FORCE)
 623                 mp->mnt_kern_flag |= MNTK_UNMOUNTF;
 624         lflags = LK_EXCLUSIVE | ((flags & MNT_FORCE) ? 0 : LK_NOWAIT);
 625         error = lockmgr(&mp->mnt_lock, lflags);
 626         if (error) {
 627                 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF);
 628                 if (mp->mnt_kern_flag & MNTK_MWAIT)
 629                         wakeup(mp);
 630                 return (error);
 631         }
 632
 633         if (mp->mnt_flag & MNT_EXPUBLIC)
 634                 vfs_setpublicfs(NULL, NULL, NULL);
 635
 636         vfs_msync(mp, MNT_WAIT);
 637         async_flag = mp->mnt_flag & MNT_ASYNC;
 638         mp->mnt_flag &=~ MNT_ASYNC;
 639
 640         /*
 641          * If this filesystem isn't aliasing other filesystems,
 642          * try to invalidate any remaining namecache entries and
 643          * check the count afterwords.
 644          */
 645         if ((mp->mnt_kern_flag & MNTK_NCALIASED) == 0) {
 646                 cache_lock(&mp->mnt_ncmountpt);
 647                 cache_inval(&mp->mnt_ncmountpt, CINV_DESTROY|CINV_CHILDREN);
 648                 cache_unlock(&mp->mnt_ncmountpt);
 649
 650                 if ((ncp = mp->mnt_ncmountpt.ncp) != NULL &&
 651                     (ncp->nc_refs != 1 || TAILQ_FIRST(&ncp->nc_list))) {
 652
 653                         if ((flags & MNT_FORCE) == 0) {
 654                                 error = EBUSY;
 655                                 mount_warning(mp, "Cannot unmount: "
 656                                                   "%d namecache "
 657                                                   "references still "
 658                                                   "present",
 659                                                   ncp->nc_refs - 1);
 660                         } else {
 661                                 mount_warning(mp, "Forced unmount: "
 662                                                   "%d namecache "
 663                                                   "references still "
 664                                                   "present",
 665                                                   ncp->nc_refs - 1);
 666                                 freeok = 0;
 667                         }
 668                 }
 669         }
 670
 671         /*
 672          * nchandle records ref the mount structure.  Expect a count of 1
 673          * (our mount->mnt_ncmountpt).
 674          */
 675         if (mp->mnt_refs != 1) {
 676                 if ((flags & MNT_FORCE) == 0) {
 677                         mount_warning(mp, "Cannot unmount: "
 678                                           "%d process references still "
 679                                           "present", mp->mnt_refs);
 680                         error = EBUSY;
 681                 } else {
 682                         mount_warning(mp, "Forced unmount: "
 683                                           "%d process references still "
 684                                           "present", mp->mnt_refs);
 685                         freeok = 0;
 686                 }
 687         }
 688
 689         /*
 690          * Decomission our special mnt_syncer vnode.  This also stops
 691          * the vnlru code.  If we are unable to unmount we recommission
 692          * the vnode.
 693          */
 694         if (error == 0) {
 695                 if ((vp = mp->mnt_syncer) != NULL) {
 696                         mp->mnt_syncer = NULL;
 697                         vrele(vp);
 698                 }
 699                 if (((mp->mnt_flag & MNT_RDONLY) ||
 700                      (error = VFS_SYNC(mp, MNT_WAIT)) == 0) ||
 701                     (flags & MNT_FORCE)) {
 702                         error = VFS_UNMOUNT(mp, flags);
 703                 }
 704         }
 705         if (error) {
 706                 if (mp->mnt_syncer == NULL)
 707                         vfs_allocate_syncvnode(mp);
 708                 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF);
 709                 mp->mnt_flag |= async_flag;
 710                 lockmgr(&mp->mnt_lock, LK_RELEASE);
 711                 if (mp->mnt_kern_flag & MNTK_MWAIT)
 712                         wakeup(mp);
 713                 return (error);
 714         }
 715         /*
 716          * Clean up any journals still associated with the mount after
 717          * filesystem activity has ceased.
 718          */
 719         journal_remove_all_journals(mp,
 720             ((flags & MNT_FORCE) ? MC_JOURNAL_STOP_IMM : 0));
 721
 722         mountlist_remove(mp);
 723
 724         /*
 725          * Remove any installed vnode ops here so the individual VFSs don't
 726          * have to.
 727          */
 728         vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_coherency_ops);
 729         vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_journal_ops);
 730         vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_norm_ops);
 731         vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_spec_ops);
 732         vfs_rm_vnodeops(mp, NULL, &mp->mnt_vn_fifo_ops);
 733
 734         if (mp->mnt_ncmountpt.ncp != NULL) {
 735                 nch = mp->mnt_ncmountpt;
 736                 cache_zero(&mp->mnt_ncmountpt);
 737                 cache_clrmountpt(&nch);
 738                 cache_drop(&nch);
 739         }
 740         if (mp->mnt_ncmounton.ncp != NULL) {
 741                 nch = mp->mnt_ncmounton;
 742                 cache_zero(&mp->mnt_ncmounton);
 743                 cache_clrmountpt(&nch);
 744                 cache_drop(&nch);
 745         }
 746
 747         mp->mnt_vfc->vfc_refcount--;
 748         if (!TAILQ_EMPTY(&mp->mnt_nvnodelist))
 749                 panic("unmount: dangling vnode");
 750         lockmgr(&mp->mnt_lock, LK_RELEASE);
 751         if (mp->mnt_kern_flag & MNTK_MWAIT)
 752                 wakeup(mp);
 753         if (freeok)
 754                 kfree(mp, M_MOUNT);
 755         return (0);
 756 }
 757
 758 static
 759 void
 760 mount_warning(struct mount *mp, const char *ctl, ...)
 761 {
 762         char *ptr;
 763         char *buf;
 764         __va_list va;
 765
 766         __va_start(va, ctl);
 767         if (cache_fullpath(NULL, &mp->mnt_ncmounton, &ptr, &buf) == 0) {
 768                 kprintf("unmount(%s): ", ptr);
 769                 kvprintf(ctl, va);
 770                 kprintf("\n");
 771                 kfree(buf, M_TEMP);
 772         } else {
 773                 kprintf("unmount(%p", mp);
 774                 if (mp->mnt_ncmounton.ncp && mp->mnt_ncmounton.ncp->nc_name)
 775                         kprintf(",%s", mp->mnt_ncmounton.ncp->nc_name);
 776                 kprintf("): ");
 777                 kvprintf(ctl, va);
 778                 kprintf("\n");
 779         }
 780         __va_end(va);
 781 }
 782
 783 /*
 784  * Shim cache_fullpath() to handle the case where a process is chrooted into
 785  * a subdirectory of a mount.  In this case if the root mount matches the
 786  * process root directory's mount we have to specify the process's root
 787  * directory instead of the mount point, because the mount point might
 788  * be above the root directory.
 789  */
 790 static
 791 int
 792 mount_path(struct proc *p, struct mount *mp, char **rb, char **fb)
 793 {
 794         struct nchandle *nch;
 795
 796         if (p && p->p_fd->fd_nrdir.mount == mp)
 797                 nch = &p->p_fd->fd_nrdir;
 798         else
 799                 nch = &mp->mnt_ncmountpt;
 800         return(cache_fullpath(p, nch, rb, fb));
 801 }
 802
 803 /*
 804  * Sync each mounted filesystem.
 805  */
 806
 807 #ifdef DEBUG
 808 static int syncprt = 0;
 809 SYSCTL_INT(_debug, OID_AUTO, syncprt, CTLFLAG_RW, &syncprt, 0, "");
 810 #endif /* DEBUG */
 811
 812 static int sync_callback(struct mount *mp, void *data);
 813
 814 /* ARGSUSED */
 815 int
 816 sys_sync(struct sync_args *uap)
 817 {
 818         mountlist_scan(sync_callback, NULL, MNTSCAN_FORWARD);
 819 #ifdef DEBUG
 820         /*
 821          * print out buffer pool stat information on each sync() call.
 822          */
 823         if (syncprt)
 824                 vfs_bufstats();
 825 #endif /* DEBUG */
 826         return (0);
 827 }
 828
 829 static
 830 int
 831 sync_callback(struct mount *mp, void *data __unused)
 832 {
 833         int asyncflag;
 834
 835         if ((mp->mnt_flag & MNT_RDONLY) == 0) {
 836                 asyncflag = mp->mnt_flag & MNT_ASYNC;
 837                 mp->mnt_flag &= ~MNT_ASYNC;
 838                 vfs_msync(mp, MNT_NOWAIT);
 839                 VFS_SYNC(mp, MNT_NOWAIT);
 840                 mp->mnt_flag |= asyncflag;
 841         }
 842         return(0);
 843 }
 844
 845 /* XXX PRISON: could be per prison flag */
 846 static int prison_quotas;
 847 #if 0
 848 SYSCTL_INT(_kern_prison, OID_AUTO, quotas, CTLFLAG_RW, &prison_quotas, 0, "");
 849 #endif
 850
 851 /*
 852  *  quotactl_args(char *path, int fcmd, int uid, caddr_t arg)
 853  *
 854  * Change filesystem quotas.
 855  */
 856 /* ARGSUSED */
 857 int
 858 sys_quotactl(struct quotactl_args *uap)
 859 {
 860         struct nlookupdata nd;
 861         struct thread *td;
 862         struct proc *p;
 863         struct mount *mp;
 864         int error;
 865
 866         td = curthread;
 867         p = td->td_proc;
 868         if (p->p_ucred->cr_prison && !prison_quotas)
 869                 return (EPERM);
 870
 871         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
 872         if (error == 0)
 873                 error = nlookup(&nd);
 874         if (error == 0) {
 875                 mp = nd.nl_nch.mount;
 876                 error = VFS_QUOTACTL(mp, uap->cmd, uap->uid,
 877                                     uap->arg, nd.nl_cred);
 878         }
 879         nlookup_done(&nd);
 880         return (error);
 881 }
 882
 883 /*
 884  * mountctl(char *path, int op, int fd, const void *ctl, int ctllen,
 885  *              void *buf, int buflen)
 886  *
 887  * This function operates on a mount point and executes the specified
 888  * operation using the specified control data, and possibly returns data.
 889  *
 890  * The actual number of bytes stored in the result buffer is returned, 0
 891  * if none, otherwise an error is returned.
 892  */
 893 /* ARGSUSED */
 894 int
 895 sys_mountctl(struct mountctl_args *uap)
 896 {
 897         struct thread *td = curthread;
 898         struct proc *p = td->td_proc;
 899         struct file *fp;
 900         void *ctl = NULL;
 901         void *buf = NULL;
 902         char *path = NULL;
 903         int error;
 904
 905         /*
 906          * Sanity and permissions checks.  We must be root.
 907          */
 908         KKASSERT(p);
 909         if (p->p_ucred->cr_prison != NULL)
 910                 return (EPERM);
 911         if ((uap->op != MOUNTCTL_MOUNTFLAGS) &&
 912             (error = priv_check(td, PRIV_ROOT)) != 0)
 913                 return (error);
 914
 915         /*
 916          * Argument length checks
 917          */
 918         if (uap->ctllen < 0 || uap->ctllen > 1024)
 919                 return (EINVAL);
 920         if (uap->buflen < 0 || uap->buflen > 16 * 1024)
 921                 return (EINVAL);
 922         if (uap->path == NULL)
 923                 return (EINVAL);
 924
 925         /*
 926          * Allocate the necessary buffers and copyin data
 927          */
 928         path = objcache_get(namei_oc, M_WAITOK);
 929         error = copyinstr(uap->path, path, MAXPATHLEN, NULL);
 930         if (error)
 931                 goto done;
 932
 933         if (uap->ctllen) {
 934                 ctl = kmalloc(uap->ctllen + 1, M_TEMP, M_WAITOK|M_ZERO);
 935                 error = copyin(uap->ctl, ctl, uap->ctllen);
 936                 if (error)
 937                         goto done;
 938         }
 939         if (uap->buflen)
 940                 buf = kmalloc(uap->buflen + 1, M_TEMP, M_WAITOK|M_ZERO);
 941
 942         /*
 943          * Validate the descriptor
 944          */
 945         if (uap->fd >= 0) {
 946                 fp = holdfp(p->p_fd, uap->fd, -1);
 947                 if (fp == NULL) {
 948                         error = EBADF;
 949                         goto done;
 950                 }
 951         } else {
 952                 fp = NULL;
 953         }
 954
 955         /*
 956          * Execute the internal kernel function and clean up.
 957          */
 958         error = kern_mountctl(path, uap->op, fp, ctl, uap->ctllen, buf, uap->buflen, &uap->sysmsg_result);
 959         if (fp)
 960                 fdrop(fp);
 961         if (error == 0 && uap->sysmsg_result > 0)
 962                 error = copyout(buf, uap->buf, uap->sysmsg_result);
 963 done:
 964         if (path)
 965                 objcache_put(namei_oc, path);
 966         if (ctl)
 967                 kfree(ctl, M_TEMP);
 968         if (buf)
 969                 kfree(buf, M_TEMP);
 970         return (error);
 971 }
 972
 973 /*
 974  * Execute a mount control operation by resolving the path to a mount point
 975  * and calling vop_mountctl().
 976  *
 977  * Use the mount point from the nch instead of the vnode so nullfs mounts
 978  * can properly spike the VOP.
 979  */
 980 int
 981 kern_mountctl(const char *path, int op, struct file *fp,
 982                 const void *ctl, int ctllen,
 983                 void *buf, int buflen, int *res)
 984 {
 985         struct vnode *vp;
 986         struct mount *mp;
 987         struct nlookupdata nd;
 988         int error;
 989
 990         *res = 0;
 991         vp = NULL;
 992         error = nlookup_init(&nd, path, UIO_SYSSPACE, NLC_FOLLOW);
 993         if (error == 0)
 994                 error = nlookup(&nd);
 995         if (error == 0)
 996                 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
 997         mp = nd.nl_nch.mount;
 998         nlookup_done(&nd);
 999         if (error)
1000                 return (error);
1001
1002         /*
1003          * Must be the root of the filesystem
1004          */
1005         if ((vp->v_flag & (VROOT|VPFSROOT)) == 0) {
1006                 vput(vp);
1007                 return (EINVAL);
1008         }
1009         error = vop_mountctl(mp->mnt_vn_use_ops, op, fp, ctl, ctllen,
1010                                 buf, buflen, res);
1011         vput(vp);
1012         return (error);
1013 }
1014
1015 int
1016 kern_statfs(struct nlookupdata *nd, struct statfs *buf)
1017 {
1018         struct thread *td = curthread;
1019         struct proc *p = td->td_proc;
1020         struct mount *mp;
1021         struct statfs *sp;
1022         char *fullpath, *freepath;
1023         int error;
1024
1025         if ((error = nlookup(nd)) != 0)
1026                 return (error);
1027         mp = nd->nl_nch.mount;
1028         sp = &mp->mnt_stat;
1029         if ((error = VFS_STATFS(mp, sp, nd->nl_cred)) != 0)
1030                 return (error);
1031
1032         error = mount_path(p, mp, &fullpath, &freepath);
1033         if (error)
1034                 return(error);
1035         bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
1036         strlcpy(sp->f_mntonname, fullpath, sizeof(sp->f_mntonname));
1037         kfree(freepath, M_TEMP);
1038
1039         sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
1040         bcopy(sp, buf, sizeof(*buf));
1041         /* Only root should have access to the fsid's. */
1042         if (priv_check(td, PRIV_ROOT))
1043                 buf->f_fsid.val[0] = buf->f_fsid.val[1] = 0;
1044         return (0);
1045 }
1046
1047 /*
1048  * statfs_args(char *path, struct statfs *buf)
1049  *
1050  * Get filesystem statistics.
1051  */
1052 int
1053 sys_statfs(struct statfs_args *uap)
1054 {
1055         struct nlookupdata nd;
1056         struct statfs buf;
1057         int error;
1058
1059         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
1060         if (error == 0)
1061                 error = kern_statfs(&nd, &buf);
1062         nlookup_done(&nd);
1063         if (error == 0)
1064                 error = copyout(&buf, uap->buf, sizeof(*uap->buf));
1065         return (error);
1066 }
1067
1068 int
1069 kern_fstatfs(int fd, struct statfs *buf)
1070 {
1071         struct thread *td = curthread;
1072         struct proc *p = td->td_proc;
1073         struct file *fp;
1074         struct mount *mp;
1075         struct statfs *sp;
1076         char *fullpath, *freepath;
1077         int error;
1078
1079         KKASSERT(p);
1080         if ((error = holdvnode(p->p_fd, fd, &fp)) != 0)
1081                 return (error);
1082         mp = ((struct vnode *)fp->f_data)->v_mount;
1083         if (mp == NULL) {
1084                 error = EBADF;
1085                 goto done;
1086         }
1087         if (fp->f_cred == NULL) {
1088                 error = EINVAL;
1089                 goto done;
1090         }
1091         sp = &mp->mnt_stat;
1092         if ((error = VFS_STATFS(mp, sp, fp->f_cred)) != 0)
1093                 goto done;
1094
1095         if ((error = mount_path(p, mp, &fullpath, &freepath)) != 0)
1096                 goto done;
1097         bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
1098         strlcpy(sp->f_mntonname, fullpath, sizeof(sp->f_mntonname));
1099         kfree(freepath, M_TEMP);
1100
1101         sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
1102         bcopy(sp, buf, sizeof(*buf));
1103
1104         /* Only root should have access to the fsid's. */
1105         if (priv_check(td, PRIV_ROOT))
1106                 buf->f_fsid.val[0] = buf->f_fsid.val[1] = 0;
1107         error = 0;
1108 done:
1109         fdrop(fp);
1110         return (error);
1111 }
1112
1113 /*
1114  * fstatfs_args(int fd, struct statfs *buf)
1115  *
1116  * Get filesystem statistics.
1117  */
1118 int
1119 sys_fstatfs(struct fstatfs_args *uap)
1120 {
1121         struct statfs buf;
1122         int error;
1123
1124         error = kern_fstatfs(uap->fd, &buf);
1125
1126         if (error == 0)
1127                 error = copyout(&buf, uap->buf, sizeof(*uap->buf));
1128         return (error);
1129 }
1130
1131 int
1132 kern_statvfs(struct nlookupdata *nd, struct statvfs *buf)
1133 {
1134         struct mount *mp;
1135         struct statvfs *sp;
1136         int error;
1137
1138         if ((error = nlookup(nd)) != 0)
1139                 return (error);
1140         mp = nd->nl_nch.mount;
1141         sp = &mp->mnt_vstat;
1142         if ((error = VFS_STATVFS(mp, sp, nd->nl_cred)) != 0)
1143                 return (error);
1144
1145         sp->f_flag = 0;
1146         if (mp->mnt_flag & MNT_RDONLY)
1147                 sp->f_flag |= ST_RDONLY;
1148         if (mp->mnt_flag & MNT_NOSUID)
1149                 sp->f_flag |= ST_NOSUID;
1150         bcopy(sp, buf, sizeof(*buf));
1151         return (0);
1152 }
1153
1154 /*
1155  * statfs_args(char *path, struct statfs *buf)
1156  *
1157  * Get filesystem statistics.
1158  */
1159 int
1160 sys_statvfs(struct statvfs_args *uap)
1161 {
1162         struct nlookupdata nd;
1163         struct statvfs buf;
1164         int error;
1165
1166         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
1167         if (error == 0)
1168                 error = kern_statvfs(&nd, &buf);
1169         nlookup_done(&nd);
1170         if (error == 0)
1171                 error = copyout(&buf, uap->buf, sizeof(*uap->buf));
1172         return (error);
1173 }
1174
1175 int
1176 kern_fstatvfs(int fd, struct statvfs *buf)
1177 {
1178         struct thread *td = curthread;
1179         struct proc *p = td->td_proc;
1180         struct file *fp;
1181         struct mount *mp;
1182         struct statvfs *sp;
1183         int error;
1184
1185         KKASSERT(p);
1186         if ((error = holdvnode(p->p_fd, fd, &fp)) != 0)
1187                 return (error);
1188         mp = ((struct vnode *)fp->f_data)->v_mount;
1189         if (mp == NULL) {
1190                 error = EBADF;
1191                 goto done;
1192         }
1193         if (fp->f_cred == NULL) {
1194                 error = EINVAL;
1195                 goto done;
1196         }
1197         sp = &mp->mnt_vstat;
1198         if ((error = VFS_STATVFS(mp, sp, fp->f_cred)) != 0)
1199                 goto done;
1200
1201         sp->f_flag = 0;
1202         if (mp->mnt_flag & MNT_RDONLY)
1203                 sp->f_flag |= ST_RDONLY;
1204         if (mp->mnt_flag & MNT_NOSUID)
1205                 sp->f_flag |= ST_NOSUID;
1206
1207         bcopy(sp, buf, sizeof(*buf));
1208         error = 0;
1209 done:
1210         fdrop(fp);
1211         return (error);
1212 }
1213
1214 /*
1215  * fstatfs_args(int fd, struct statfs *buf)
1216  *
1217  * Get filesystem statistics.
1218  */
1219 int
1220 sys_fstatvfs(struct fstatvfs_args *uap)
1221 {
1222         struct statvfs buf;
1223         int error;
1224
1225         error = kern_fstatvfs(uap->fd, &buf);
1226
1227         if (error == 0)
1228                 error = copyout(&buf, uap->buf, sizeof(*uap->buf));
1229         return (error);
1230 }
1231
1232 /*
1233  * getfsstat_args(struct statfs *buf, long bufsize, int flags)
1234  *
1235  * Get statistics on all filesystems.
1236  */
1237
1238 struct getfsstat_info {
1239         struct statfs *sfsp;
1240         long count;
1241         long maxcount;
1242         int error;
1243         int flags;
1244         struct proc *p;
1245 };
1246
1247 static int getfsstat_callback(struct mount *, void *);
1248
1249 /* ARGSUSED */
1250 int
1251 sys_getfsstat(struct getfsstat_args *uap)
1252 {
1253         struct thread *td = curthread;
1254         struct proc *p = td->td_proc;
1255         struct getfsstat_info info;
1256
1257         bzero(&info, sizeof(info));
1258
1259         info.maxcount = uap->bufsize / sizeof(struct statfs);
1260         info.sfsp = uap->buf;
1261         info.count = 0;
1262         info.flags = uap->flags;
1263         info.p = p;
1264
1265         mountlist_scan(getfsstat_callback, &info, MNTSCAN_FORWARD);
1266         if (info.sfsp && info.count > info.maxcount)
1267                 uap->sysmsg_result = info.maxcount;
1268         else
1269                 uap->sysmsg_result = info.count;
1270         return (info.error);
1271 }
1272
1273 static int
1274 getfsstat_callback(struct mount *mp, void *data)
1275 {
1276         struct getfsstat_info *info = data;
1277         struct statfs *sp;
1278         char *freepath;
1279         char *fullpath;
1280         int error;
1281
1282         if (info->sfsp && info->count < info->maxcount) {
1283                 if (info->p && !chroot_visible_mnt(mp, info->p))
1284                         return(0);
1285                 sp = &mp->mnt_stat;
1286
1287                 /*
1288                  * If MNT_NOWAIT or MNT_LAZY is specified, do not
1289                  * refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
1290                  * overrides MNT_WAIT.
1291                  */
1292                 if (((info->flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
1293                     (info->flags & MNT_WAIT)) &&
1294                     (error = VFS_STATFS(mp, sp, info->p->p_ucred))) {
1295                         return(0);
1296                 }
1297                 sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
1298
1299                 error = mount_path(info->p, mp, &fullpath, &freepath);
1300                 if (error) {
1301                         info->error = error;
1302                         return(-1);
1303                 }
1304                 bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
1305                 strlcpy(sp->f_mntonname, fullpath, sizeof(sp->f_mntonname));
1306                 kfree(freepath, M_TEMP);
1307
1308                 error = copyout(sp, info->sfsp, sizeof(*sp));
1309                 if (error) {
1310                         info->error = error;
1311                         return (-1);
1312                 }
1313                 ++info->sfsp;
1314         }
1315         info->count++;
1316         return(0);
1317 }
1318
1319 /*
1320  * getvfsstat_args(struct statfs *buf, struct statvfs *vbuf,
1321                    long bufsize, int flags)
1322  *
1323  * Get statistics on all filesystems.
1324  */
1325
1326 struct getvfsstat_info {
1327         struct statfs *sfsp;
1328         struct statvfs *vsfsp;
1329         long count;
1330         long maxcount;
1331         int error;
1332         int flags;
1333         struct proc *p;
1334 };
1335
1336 static int getvfsstat_callback(struct mount *, void *);
1337
1338 /* ARGSUSED */
1339 int
1340 sys_getvfsstat(struct getvfsstat_args *uap)
1341 {
1342         struct thread *td = curthread;
1343         struct proc *p = td->td_proc;
1344         struct getvfsstat_info info;
1345
1346         bzero(&info, sizeof(info));
1347
1348         info.maxcount = uap->vbufsize / sizeof(struct statvfs);
1349         info.sfsp = uap->buf;
1350         info.vsfsp = uap->vbuf;
1351         info.count = 0;
1352         info.flags = uap->flags;
1353         info.p = p;
1354
1355         mountlist_scan(getvfsstat_callback, &info, MNTSCAN_FORWARD);
1356         if (info.vsfsp && info.count > info.maxcount)
1357                 uap->sysmsg_result = info.maxcount;
1358         else
1359                 uap->sysmsg_result = info.count;
1360         return (info.error);
1361 }
1362
1363 static int
1364 getvfsstat_callback(struct mount *mp, void *data)
1365 {
1366         struct getvfsstat_info *info = data;
1367         struct statfs *sp;
1368         struct statvfs *vsp;
1369         char *freepath;
1370         char *fullpath;
1371         int error;
1372
1373         if (info->vsfsp && info->count < info->maxcount) {
1374                 if (info->p && !chroot_visible_mnt(mp, info->p))
1375                         return(0);
1376                 sp = &mp->mnt_stat;
1377                 vsp = &mp->mnt_vstat;
1378
1379                 /*
1380                  * If MNT_NOWAIT or MNT_LAZY is specified, do not
1381                  * refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
1382                  * overrides MNT_WAIT.
1383                  */
1384                 if (((info->flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
1385                     (info->flags & MNT_WAIT)) &&
1386                     (error = VFS_STATFS(mp, sp, info->p->p_ucred))) {
1387                         return(0);
1388                 }
1389                 sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
1390
1391                 if (((info->flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
1392                     (info->flags & MNT_WAIT)) &&
1393                     (error = VFS_STATVFS(mp, vsp, info->p->p_ucred))) {
1394                         return(0);
1395                 }
1396                 vsp->f_flag = 0;
1397                 if (mp->mnt_flag & MNT_RDONLY)
1398                         vsp->f_flag |= ST_RDONLY;
1399                 if (mp->mnt_flag & MNT_NOSUID)
1400                         vsp->f_flag |= ST_NOSUID;
1401
1402                 error = mount_path(info->p, mp, &fullpath, &freepath);
1403                 if (error) {
1404                         info->error = error;
1405                         return(-1);
1406                 }
1407                 bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
1408                 strlcpy(sp->f_mntonname, fullpath, sizeof(sp->f_mntonname));
1409                 kfree(freepath, M_TEMP);
1410
1411                 error = copyout(sp, info->sfsp, sizeof(*sp));
1412                 if (error == 0)
1413                         error = copyout(vsp, info->vsfsp, sizeof(*vsp));
1414                 if (error) {
1415                         info->error = error;
1416                         return (-1);
1417                 }
1418                 ++info->sfsp;
1419                 ++info->vsfsp;
1420         }
1421         info->count++;
1422         return(0);
1423 }
1424
1425
1426 /*
1427  * fchdir_args(int fd)
1428  *
1429  * Change current working directory to a given file descriptor.
1430  */
1431 /* ARGSUSED */
1432 int
1433 sys_fchdir(struct fchdir_args *uap)
1434 {
1435         struct thread *td = curthread;
1436         struct proc *p = td->td_proc;
1437         struct filedesc *fdp = p->p_fd;
1438         struct vnode *vp, *ovp;
1439         struct mount *mp;
1440         struct file *fp;
1441         struct nchandle nch, onch, tnch;
1442         int error;
1443
1444         if ((error = holdvnode(fdp, uap->fd, &fp)) != 0)
1445                 return (error);
1446         vp = (struct vnode *)fp->f_data;
1447         vref(vp);
1448         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1449         if (vp->v_type != VDIR || fp->f_nchandle.ncp == NULL)
1450                 error = ENOTDIR;
1451         else
1452                 error = VOP_ACCESS(vp, VEXEC, p->p_ucred);
1453         if (error) {
1454                 vput(vp);
1455                 fdrop(fp);
1456                 return (error);
1457         }
1458         cache_copy(&fp->f_nchandle, &nch);
1459
1460         /*
1461          * If the ncp has become a mount point, traverse through
1462          * the mount point.
1463          */
1464
1465         while (!error && (nch.ncp->nc_flag & NCF_ISMOUNTPT) &&
1466                (mp = cache_findmount(&nch)) != NULL
1467         ) {
1468                 error = nlookup_mp(mp, &tnch);
1469                 if (error == 0) {
1470                         cache_unlock(&tnch);    /* leave ref intact */
1471                         vput(vp);
1472                         vp = tnch.ncp->nc_vp;
1473                         error = vget(vp, LK_SHARED);
1474                         KKASSERT(error == 0);
1475                         cache_drop(&nch);
1476                         nch = tnch;
1477                 }
1478         }
1479         if (error == 0) {
1480                 ovp = fdp->fd_cdir;
1481                 onch = fdp->fd_ncdir;
1482                 vn_unlock(vp);          /* leave ref intact */
1483                 fdp->fd_cdir = vp;
1484                 fdp->fd_ncdir = nch;
1485                 cache_drop(&onch);
1486                 vrele(ovp);
1487         } else {
1488                 cache_drop(&nch);
1489                 vput(vp);
1490         }
1491         fdrop(fp);
1492         return (error);
1493 }
1494
1495 int
1496 kern_chdir(struct nlookupdata *nd)
1497 {
1498         struct thread *td = curthread;
1499         struct proc *p = td->td_proc;
1500         struct filedesc *fdp = p->p_fd;
1501         struct vnode *vp, *ovp;
1502         struct nchandle onch;
1503         int error;
1504
1505         if ((error = nlookup(nd)) != 0)
1506                 return (error);
1507         if ((vp = nd->nl_nch.ncp->nc_vp) == NULL)
1508                 return (ENOENT);
1509         if ((error = vget(vp, LK_SHARED)) != 0)
1510                 return (error);
1511
1512         error = checkvp_chdir(vp, td);
1513         vn_unlock(vp);
1514         if (error == 0) {
1515                 ovp = fdp->fd_cdir;
1516                 onch = fdp->fd_ncdir;
1517                 cache_unlock(&nd->nl_nch);      /* leave reference intact */
1518                 fdp->fd_ncdir = nd->nl_nch;
1519                 fdp->fd_cdir = vp;
1520                 cache_drop(&onch);
1521                 vrele(ovp);
1522                 cache_zero(&nd->nl_nch);
1523         } else {
1524                 vrele(vp);
1525         }
1526         return (error);
1527 }
1528
1529 /*
1530  * chdir_args(char *path)
1531  *
1532  * Change current working directory (``.'').
1533  */
1534 int
1535 sys_chdir(struct chdir_args *uap)
1536 {
1537         struct nlookupdata nd;
1538         int error;
1539
1540         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
1541         if (error == 0)
1542                 error = kern_chdir(&nd);
1543         nlookup_done(&nd);
1544         return (error);
1545 }
1546
1547 /*
1548  * Helper function for raised chroot(2) security function:  Refuse if
1549  * any filedescriptors are open directories.
1550  */
1551 static int
1552 chroot_refuse_vdir_fds(struct filedesc *fdp)
1553 {
1554         struct vnode *vp;
1555         struct file *fp;
1556         int error;
1557         int fd;
1558
1559         for (fd = 0; fd < fdp->fd_nfiles ; fd++) {
1560                 if ((error = holdvnode(fdp, fd, &fp)) != 0)
1561                         continue;
1562                 vp = (struct vnode *)fp->f_data;
1563                 if (vp->v_type != VDIR) {
1564                         fdrop(fp);
1565                         continue;
1566                 }
1567                 fdrop(fp);
1568                 return(EPERM);
1569         }
1570         return (0);
1571 }
1572
1573 /*
1574  * This sysctl determines if we will allow a process to chroot(2) if it
1575  * has a directory open:
1576  *      0: disallowed for all processes.
1577  *      1: allowed for processes that were not already chroot(2)'ed.
1578  *      2: allowed for all processes.
1579  */
1580
1581 static int chroot_allow_open_directories = 1;
1582
1583 SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW,
1584      &chroot_allow_open_directories, 0, "");
1585
1586 /*
1587  * chroot to the specified namecache entry.  We obtain the vp from the
1588  * namecache data.  The passed ncp must be locked and referenced and will
1589  * remain locked and referenced on return.
1590  */
1591 int
1592 kern_chroot(struct nchandle *nch)
1593 {
1594         struct thread *td = curthread;
1595         struct proc *p = td->td_proc;
1596         struct filedesc *fdp = p->p_fd;
1597         struct vnode *vp;
1598         int error;
1599
1600         /*
1601          * Only privileged user can chroot
1602          */
1603         error = priv_check_cred(p->p_ucred, PRIV_VFS_CHROOT, 0);
1604         if (error)
1605                 return (error);
1606
1607         /*
1608          * Disallow open directory descriptors (fchdir() breakouts).
1609          */
1610         if (chroot_allow_open_directories == 0 ||
1611            (chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) {
1612                 if ((error = chroot_refuse_vdir_fds(fdp)) != 0)
1613                         return (error);
1614         }
1615         if ((vp = nch->ncp->nc_vp) == NULL)
1616                 return (ENOENT);
1617
1618         if ((error = vget(vp, LK_SHARED)) != 0)
1619                 return (error);
1620
1621         /*
1622          * Check the validity of vp as a directory to change to and
1623          * associate it with rdir/jdir.
1624          */
1625         error = checkvp_chdir(vp, td);
1626         vn_unlock(vp);                  /* leave reference intact */
1627         if (error == 0) {
1628                 vrele(fdp->fd_rdir);
1629                 fdp->fd_rdir = vp;      /* reference inherited by fd_rdir */
1630                 cache_drop(&fdp->fd_nrdir);
1631                 cache_copy(nch, &fdp->fd_nrdir);
1632                 if (fdp->fd_jdir == NULL) {
1633                         fdp->fd_jdir = vp;
1634                         vref(fdp->fd_jdir);
1635                         cache_copy(nch, &fdp->fd_njdir);
1636                 }
1637         } else {
1638                 vrele(vp);
1639         }
1640         return (error);
1641 }
1642
1643 /*
1644  * chroot_args(char *path)
1645  *
1646  * Change notion of root (``/'') directory.
1647  */
1648 /* ARGSUSED */
1649 int
1650 sys_chroot(struct chroot_args *uap)
1651 {
1652         struct thread *td = curthread;
1653         struct nlookupdata nd;
1654         int error;
1655
1656         KKASSERT(td->td_proc);
1657         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
1658         if (error) {
1659                 nlookup_done(&nd);
1660                 return(error);
1661         }
1662         nd.nl_flags |= NLC_EXEC;
1663         error = nlookup(&nd);
1664         if (error == 0)
1665                 error = kern_chroot(&nd.nl_nch);
1666         nlookup_done(&nd);
1667         return(error);
1668 }
1669
1670 /*
1671  * Common routine for chroot and chdir.  Given a locked, referenced vnode,
1672  * determine whether it is legal to chdir to the vnode.  The vnode's state
1673  * is not changed by this call.
1674  */
1675 int
1676 checkvp_chdir(struct vnode *vp, struct thread *td)
1677 {
1678         int error;
1679
1680         if (vp->v_type != VDIR)
1681                 error = ENOTDIR;
1682         else
1683                 error = VOP_ACCESS(vp, VEXEC, td->td_proc->p_ucred);
1684         return (error);
1685 }
1686
1687 int
1688 kern_open(struct nlookupdata *nd, int oflags, int mode, int *res)
1689 {
1690         struct thread *td = curthread;
1691         struct proc *p = td->td_proc;
1692         struct lwp *lp = td->td_lwp;
1693         struct filedesc *fdp = p->p_fd;
1694         int cmode, flags;
1695         struct file *nfp;
1696         struct file *fp;
1697         struct vnode *vp;
1698         int type, indx, error;
1699         struct flock lf;
1700
1701         if ((oflags & O_ACCMODE) == O_ACCMODE)
1702                 return (EINVAL);
1703         flags = FFLAGS(oflags);
1704         error = falloc(p, &nfp, NULL);
1705         if (error)
1706                 return (error);
1707         fp = nfp;
1708         cmode = ((mode &~ fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT;
1709
1710         /*
1711          * XXX p_dupfd is a real mess.  It allows a device to return a
1712          * file descriptor to be duplicated rather then doing the open
1713          * itself.
1714          */
1715         lp->lwp_dupfd = -1;
1716
1717         /*
1718          * Call vn_open() to do the lookup and assign the vnode to the
1719          * file pointer.  vn_open() does not change the ref count on fp
1720          * and the vnode, on success, will be inherited by the file pointer
1721          * and unlocked.
1722          */
1723         nd->nl_flags |= NLC_LOCKVP;
1724         error = vn_open(nd, fp, flags, cmode);
1725         nlookup_done(nd);
1726         if (error) {
1727                 /*
1728                  * handle special fdopen() case.  bleh.  dupfdopen() is
1729                  * responsible for dropping the old contents of ofiles[indx]
1730                  * if it succeeds.
1731                  *
1732                  * Note that fsetfd() will add a ref to fp which represents
1733                  * the fd_files[] assignment.  We must still drop our
1734                  * reference.
1735                  */
1736                 if ((error == ENODEV || error == ENXIO) && lp->lwp_dupfd >= 0) {
1737                         if (fdalloc(p, 0, &indx) == 0) {
1738                                 error = dupfdopen(p, indx, lp->lwp_dupfd, flags, error);
1739                                 if (error == 0) {
1740                                         *res = indx;
1741                                         fdrop(fp);      /* our ref */
1742                                         return (0);
1743                                 }
1744                                 fsetfd(p, NULL, indx);
1745                         }
1746                 }
1747                 fdrop(fp);      /* our ref */
1748                 if (error == ERESTART)
1749                         error = EINTR;
1750                 return (error);
1751         }
1752
1753         /*
1754          * ref the vnode for ourselves so it can't be ripped out from under
1755          * is.  XXX need an ND flag to request that the vnode be returned
1756          * anyway.
1757          *
1758          * Reserve a file descriptor but do not assign it until the open
1759          * succeeds.
1760          */
1761         vp = (struct vnode *)fp->f_data;
1762         vref(vp);
1763         if ((error = fdalloc(p, 0, &indx)) != 0) {
1764                 fdrop(fp);
1765                 vrele(vp);
1766                 return (error);
1767         }
1768
1769         /*
1770          * If no error occurs the vp will have been assigned to the file
1771          * pointer.
1772          */
1773         lp->lwp_dupfd = 0;
1774
1775         if (flags & (O_EXLOCK | O_SHLOCK)) {
1776                 lf.l_whence = SEEK_SET;
1777                 lf.l_start = 0;
1778                 lf.l_len = 0;
1779                 if (flags & O_EXLOCK)
1780                         lf.l_type = F_WRLCK;
1781                 else
1782                         lf.l_type = F_RDLCK;
1783                 if (flags & FNONBLOCK)
1784                         type = 0;
1785                 else
1786                         type = F_WAIT;
1787
1788                 if ((error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type)) != 0) {
1789                         /*
1790                          * lock request failed.  Clean up the reserved
1791                          * descriptor.
1792                          */
1793                         vrele(vp);
1794                         fsetfd(p, NULL, indx);
1795                         fdrop(fp);
1796                         return (error);
1797                 }
1798                 fp->f_flag |= FHASLOCK;
1799         }
1800 #if 0
1801         /*
1802          * Assert that all regular file vnodes were created with a object.
1803          */
1804         KASSERT(vp->v_type != VREG || vp->v_object != NULL,
1805                 ("open: regular file has no backing object after vn_open"));
1806 #endif
1807
1808         vrele(vp);
1809
1810         /*
1811          * release our private reference, leaving the one associated with the
1812          * descriptor table intact.
1813          */
1814         fsetfd(p, fp, indx);
1815         fdrop(fp);
1816         *res = indx;
1817         return (0);
1818 }
1819
1820 /*
1821  * open_args(char *path, int flags, int mode)
1822  *
1823  * Check permissions, allocate an open file structure,
1824  * and call the device open routine if any.
1825  */
1826 int
1827 sys_open(struct open_args *uap)
1828 {
1829         struct nlookupdata nd;
1830         int error;
1831
1832         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
1833         if (error == 0) {
1834                 error = kern_open(&nd, uap->flags,
1835                                     uap->mode, &uap->sysmsg_result);
1836         }
1837         nlookup_done(&nd);
1838         return (error);
1839 }
1840
1841 /*
1842  * openat_args(int fd, char *path, int flags, int mode)
1843  */
1844 int
1845 sys_openat(struct openat_args *uap)
1846 {
1847         struct nlookupdata nd;
1848         int error;
1849         struct file *fp;
1850
1851         error = nlookup_init_at(&nd, &fp, uap->fd, uap->path, UIO_USERSPACE, 0);
1852         if (error == 0) {
1853                 error = kern_open(&nd, uap->flags, uap->mode,
1854                                         &uap->sysmsg_result);
1855         }
1856         nlookup_done_at(&nd, fp);
1857         return (error);
1858 }
1859
1860 int
1861 kern_mknod(struct nlookupdata *nd, int mode, int rmajor, int rminor)
1862 {
1863         struct thread *td = curthread;
1864         struct proc *p = td->td_proc;
1865         struct vnode *vp;
1866         struct vattr vattr;
1867         int error;
1868         int whiteout = 0;
1869
1870         KKASSERT(p);
1871
1872         VATTR_NULL(&vattr);
1873         vattr.va_mode = (mode & ALLPERMS) &~ p->p_fd->fd_cmask;
1874         vattr.va_rmajor = rmajor;
1875         vattr.va_rminor = rminor;
1876
1877         switch (mode & S_IFMT) {
1878         case S_IFMT:    /* used by badsect to flag bad sectors */
1879                 error = priv_check_cred(p->p_ucred, PRIV_VFS_MKNOD_BAD, 0);
1880                 vattr.va_type = VBAD;
1881                 break;
1882         case S_IFCHR:
1883                 error = priv_check(td, PRIV_VFS_MKNOD_DEV);
1884                 vattr.va_type = VCHR;
1885                 break;
1886         case S_IFBLK:
1887                 error = priv_check(td, PRIV_VFS_MKNOD_DEV);
1888                 vattr.va_type = VBLK;
1889                 break;
1890         case S_IFWHT:
1891                 error = priv_check_cred(p->p_ucred, PRIV_VFS_MKNOD_WHT, 0);
1892                 whiteout = 1;
1893                 break;
1894         case S_IFDIR:   /* special directories support for HAMMER */
1895                 error = priv_check_cred(p->p_ucred, PRIV_VFS_MKNOD_DIR, 0);
1896                 vattr.va_type = VDIR;
1897                 break;
1898         default:
1899                 error = EINVAL;
1900                 break;
1901         }
1902
1903         if (error)
1904                 return (error);
1905
1906         bwillinode(1);
1907         nd->nl_flags |= NLC_CREATE | NLC_REFDVP;
1908         if ((error = nlookup(nd)) != 0)
1909                 return (error);
1910         if (nd->nl_nch.ncp->nc_vp)
1911                 return (EEXIST);
1912         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
1913                 return (error);
1914
1915         if (whiteout) {
1916                 error = VOP_NWHITEOUT(&nd->nl_nch, nd->nl_dvp,
1917                                       nd->nl_cred, NAMEI_CREATE);
1918         } else {
1919                 vp = NULL;
1920                 error = VOP_NMKNOD(&nd->nl_nch, nd->nl_dvp,
1921                                    &vp, nd->nl_cred, &vattr);
1922                 if (error == 0)
1923                         vput(vp);
1924         }
1925         return (error);
1926 }
1927
1928 /*
1929  * mknod_args(char *path, int mode, int dev)
1930  *
1931  * Create a special file.
1932  */
1933 int
1934 sys_mknod(struct mknod_args *uap)
1935 {
1936         struct nlookupdata nd;
1937         int error;
1938
1939         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
1940         if (error == 0) {
1941                 error = kern_mknod(&nd, uap->mode,
1942                                    umajor(uap->dev), uminor(uap->dev));
1943         }
1944         nlookup_done(&nd);
1945         return (error);
1946 }
1947
1948 int
1949 kern_mkfifo(struct nlookupdata *nd, int mode)
1950 {
1951         struct thread *td = curthread;
1952         struct proc *p = td->td_proc;
1953         struct vattr vattr;
1954         struct vnode *vp;
1955         int error;
1956
1957         bwillinode(1);
1958
1959         nd->nl_flags |= NLC_CREATE | NLC_REFDVP;
1960         if ((error = nlookup(nd)) != 0)
1961                 return (error);
1962         if (nd->nl_nch.ncp->nc_vp)
1963                 return (EEXIST);
1964         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
1965                 return (error);
1966
1967         VATTR_NULL(&vattr);
1968         vattr.va_type = VFIFO;
1969         vattr.va_mode = (mode & ALLPERMS) &~ p->p_fd->fd_cmask;
1970         vp = NULL;
1971         error = VOP_NMKNOD(&nd->nl_nch, nd->nl_dvp, &vp, nd->nl_cred, &vattr);
1972         if (error == 0)
1973                 vput(vp);
1974         return (error);
1975 }
1976
1977 /*
1978  * mkfifo_args(char *path, int mode)
1979  *
1980  * Create a named pipe.
1981  */
1982 int
1983 sys_mkfifo(struct mkfifo_args *uap)
1984 {
1985         struct nlookupdata nd;
1986         int error;
1987
1988         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
1989         if (error == 0)
1990                 error = kern_mkfifo(&nd, uap->mode);
1991         nlookup_done(&nd);
1992         return (error);
1993 }
1994
1995 static int hardlink_check_uid = 0;
1996 SYSCTL_INT(_security, OID_AUTO, hardlink_check_uid, CTLFLAG_RW,
1997     &hardlink_check_uid, 0,
1998     "Unprivileged processes cannot create hard links to files owned by other "
1999     "users");
2000 static int hardlink_check_gid = 0;
2001 SYSCTL_INT(_security, OID_AUTO, hardlink_check_gid, CTLFLAG_RW,
2002     &hardlink_check_gid, 0,
2003     "Unprivileged processes cannot create hard links to files owned by other "
2004     "groups");
2005
2006 static int
2007 can_hardlink(struct vnode *vp, struct thread *td, struct ucred *cred)
2008 {
2009         struct vattr va;
2010         int error;
2011
2012         /*
2013          * Shortcut if disabled
2014          */
2015         if (hardlink_check_uid == 0 && hardlink_check_gid == 0)
2016                 return (0);
2017
2018         /*
2019          * Privileged user can always hardlink
2020          */
2021         if (priv_check_cred(cred, PRIV_VFS_LINK, 0) == 0)
2022                 return (0);
2023
2024         /*
2025          * Otherwise only if the originating file is owned by the
2026          * same user or group.  Note that any group is allowed if
2027          * the file is owned by the caller.
2028          */
2029         error = VOP_GETATTR(vp, &va);
2030         if (error != 0)
2031                 return (error);
2032
2033         if (hardlink_check_uid) {
2034                 if (cred->cr_uid != va.va_uid)
2035                         return (EPERM);
2036         }
2037
2038         if (hardlink_check_gid) {
2039                 if (cred->cr_uid != va.va_uid && !groupmember(va.va_gid, cred))
2040                         return (EPERM);
2041         }
2042
2043         return (0);
2044 }
2045
2046 int
2047 kern_link(struct nlookupdata *nd, struct nlookupdata *linknd)
2048 {
2049         struct thread *td = curthread;
2050         struct vnode *vp;
2051         int error;
2052
2053         /*
2054          * Lookup the source and obtained a locked vnode.
2055          *
2056          * You may only hardlink a file which you have write permission
2057          * on or which you own.
2058          *
2059          * XXX relookup on vget failure / race ?
2060          */
2061         bwillinode(1);
2062         nd->nl_flags |= NLC_WRITE | NLC_OWN | NLC_HLINK;
2063         if ((error = nlookup(nd)) != 0)
2064                 return (error);
2065         vp = nd->nl_nch.ncp->nc_vp;
2066         KKASSERT(vp != NULL);
2067         if (vp->v_type == VDIR)
2068                 return (EPERM);         /* POSIX */
2069         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
2070                 return (error);
2071         if ((error = vget(vp, LK_EXCLUSIVE)) != 0)
2072                 return (error);
2073
2074         /*
2075          * Unlock the source so we can lookup the target without deadlocking
2076          * (XXX vp is locked already, possible other deadlock?).  The target
2077          * must not exist.
2078          */
2079         KKASSERT(nd->nl_flags & NLC_NCPISLOCKED);
2080         nd->nl_flags &= ~NLC_NCPISLOCKED;
2081         cache_unlock(&nd->nl_nch);
2082
2083         linknd->nl_flags |= NLC_CREATE | NLC_REFDVP;
2084         if ((error = nlookup(linknd)) != 0) {
2085                 vput(vp);
2086                 return (error);
2087         }
2088         if (linknd->nl_nch.ncp->nc_vp) {
2089                 vput(vp);
2090                 return (EEXIST);
2091         }
2092
2093         /*
2094          * Finally run the new API VOP.
2095          */
2096         error = can_hardlink(vp, td, td->td_proc->p_ucred);
2097         if (error == 0) {
2098                 error = VOP_NLINK(&linknd->nl_nch, linknd->nl_dvp,
2099                                   vp, linknd->nl_cred);
2100         }
2101         vput(vp);
2102         return (error);
2103 }
2104
2105 /*
2106  * link_args(char *path, char *link)
2107  *
2108  * Make a hard file link.
2109  */
2110 int
2111 sys_link(struct link_args *uap)
2112 {
2113         struct nlookupdata nd, linknd;
2114         int error;
2115
2116         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2117         if (error == 0) {
2118                 error = nlookup_init(&linknd, uap->link, UIO_USERSPACE, 0);
2119                 if (error == 0)
2120                         error = kern_link(&nd, &linknd);
2121                 nlookup_done(&linknd);
2122         }
2123         nlookup_done(&nd);
2124         return (error);
2125 }
2126
2127 int
2128 kern_symlink(struct nlookupdata *nd, char *path, int mode)
2129 {
2130         struct vattr vattr;
2131         struct vnode *vp;
2132         struct vnode *dvp;
2133         int error;
2134
2135         bwillinode(1);
2136         nd->nl_flags |= NLC_CREATE | NLC_REFDVP;
2137         if ((error = nlookup(nd)) != 0)
2138                 return (error);
2139         if (nd->nl_nch.ncp->nc_vp)
2140                 return (EEXIST);
2141         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
2142                 return (error);
2143         dvp = nd->nl_dvp;
2144         VATTR_NULL(&vattr);
2145         vattr.va_mode = mode;
2146         error = VOP_NSYMLINK(&nd->nl_nch, dvp, &vp, nd->nl_cred, &vattr, path);
2147         if (error == 0)
2148                 vput(vp);
2149         return (error);
2150 }
2151
2152 /*
2153  * symlink(char *path, char *link)
2154  *
2155  * Make a symbolic link.
2156  */
2157 int
2158 sys_symlink(struct symlink_args *uap)
2159 {
2160         struct thread *td = curthread;
2161         struct nlookupdata nd;
2162         char *path;
2163         int error;
2164         int mode;
2165
2166         path = objcache_get(namei_oc, M_WAITOK);
2167         error = copyinstr(uap->path, path, MAXPATHLEN, NULL);
2168         if (error == 0) {
2169                 error = nlookup_init(&nd, uap->link, UIO_USERSPACE, 0);
2170                 if (error == 0) {
2171                         mode = ACCESSPERMS & ~td->td_proc->p_fd->fd_cmask;
2172                         error = kern_symlink(&nd, path, mode);
2173                 }
2174                 nlookup_done(&nd);
2175         }
2176         objcache_put(namei_oc, path);
2177         return (error);
2178 }
2179
2180 /*
2181  * undelete_args(char *path)
2182  *
2183  * Delete a whiteout from the filesystem.
2184  */
2185 /* ARGSUSED */
2186 int
2187 sys_undelete(struct undelete_args *uap)
2188 {
2189         struct nlookupdata nd;
2190         int error;
2191
2192         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2193         bwillinode(1);
2194         nd.nl_flags |= NLC_DELETE | NLC_REFDVP;
2195         if (error == 0)
2196                 error = nlookup(&nd);
2197         if (error == 0)
2198                 error = ncp_writechk(&nd.nl_nch);
2199         if (error == 0) {
2200                 error = VOP_NWHITEOUT(&nd.nl_nch, nd.nl_dvp, nd.nl_cred,
2201                                       NAMEI_DELETE);
2202         }
2203         nlookup_done(&nd);
2204         return (error);
2205 }
2206
2207 int
2208 kern_unlink(struct nlookupdata *nd)
2209 {
2210         int error;
2211
2212         bwillinode(1);
2213         nd->nl_flags |= NLC_DELETE | NLC_REFDVP;
2214         if ((error = nlookup(nd)) != 0)
2215                 return (error);
2216         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
2217                 return (error);
2218         error = VOP_NREMOVE(&nd->nl_nch, nd->nl_dvp, nd->nl_cred);
2219         return (error);
2220 }
2221
2222 /*
2223  * unlink_args(char *path)
2224  *
2225  * Delete a name from the filesystem.
2226  */
2227 int
2228 sys_unlink(struct unlink_args *uap)
2229 {
2230         struct nlookupdata nd;
2231         int error;
2232
2233         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2234         if (error == 0)
2235                 error = kern_unlink(&nd);
2236         nlookup_done(&nd);
2237         return (error);
2238 }
2239
2240
2241 /*
2242  * unlinkat_args(int fd, char *path, int flags)
2243  *
2244  * Delete the file or directory entry pointed to by fd/path.
2245  */
2246 int
2247 sys_unlinkat(struct unlinkat_args *uap)
2248 {
2249         struct nlookupdata nd;
2250         struct file *fp;
2251         int error;
2252
2253         if (uap->flags & ~AT_REMOVEDIR)
2254                 return (EINVAL);
2255
2256         error = nlookup_init_at(&nd, &fp, uap->fd, uap->path, UIO_USERSPACE, 0);
2257         if (error == 0) {
2258                 if (uap->flags & AT_REMOVEDIR)
2259                         error = kern_rmdir(&nd);
2260                 else
2261                         error = kern_unlink(&nd);
2262         }
2263         nlookup_done_at(&nd, fp);
2264         return (error);
2265 }
2266
2267 int
2268 kern_lseek(int fd, off_t offset, int whence, off_t *res)
2269 {
2270         struct thread *td = curthread;
2271         struct proc *p = td->td_proc;
2272         struct file *fp;
2273         struct vnode *vp;
2274         struct vattr vattr;
2275         off_t new_offset;
2276         int error;
2277
2278         fp = holdfp(p->p_fd, fd, -1);
2279         if (fp == NULL)
2280                 return (EBADF);
2281         if (fp->f_type != DTYPE_VNODE) {
2282                 error = ESPIPE;
2283                 goto done;
2284         }
2285         vp = (struct vnode *)fp->f_data;
2286
2287         switch (whence) {
2288         case L_INCR:
2289                 new_offset = fp->f_offset + offset;
2290                 error = 0;
2291                 break;
2292         case L_XTND:
2293                 error = VOP_GETATTR(vp, &vattr);
2294                 new_offset = offset + vattr.va_size;
2295                 break;
2296         case L_SET:
2297                 new_offset = offset;
2298                 error = 0;
2299                 break;
2300         default:
2301                 new_offset = 0;
2302                 error = EINVAL;
2303                 break;
2304         }
2305
2306         /*
2307          * Validate the seek position.  Negative offsets are not allowed
2308          * for regular files or directories.
2309          *
2310          * Normally we would also not want to allow negative offsets for
2311          * character and block-special devices.  However kvm addresses
2312          * on 64 bit architectures might appear to be negative and must
2313          * be allowed.
2314          */
2315         if (error == 0) {
2316                 if (new_offset < 0 &&
2317                     (vp->v_type == VREG || vp->v_type == VDIR)) {
2318                         error = EINVAL;
2319                 } else {
2320                         fp->f_offset = new_offset;
2321                 }
2322         }
2323         *res = fp->f_offset;
2324 done:
2325         fdrop(fp);
2326         return (error);
2327 }
2328
2329 /*
2330  * lseek_args(int fd, int pad, off_t offset, int whence)
2331  *
2332  * Reposition read/write file offset.
2333  */
2334 int
2335 sys_lseek(struct lseek_args *uap)
2336 {
2337         int error;
2338
2339         error = kern_lseek(uap->fd, uap->offset, uap->whence,
2340                            &uap->sysmsg_offset);
2341
2342         return (error);
2343 }
2344
2345 /*
2346  * Check if current process can access given file.  amode is a bitmask of *_OK
2347  * access bits.  flags is a bitmask of AT_* flags.
2348  */
2349 int
2350 kern_access(struct nlookupdata *nd, int amode, int flags)
2351 {
2352         struct vnode *vp;
2353         int error, mode;
2354
2355         if (flags & ~AT_EACCESS)
2356                 return (EINVAL);
2357         if ((error = nlookup(nd)) != 0)
2358                 return (error);
2359 retry:
2360         error = cache_vget(&nd->nl_nch, nd->nl_cred, LK_EXCLUSIVE, &vp);
2361         if (error)
2362                 return (error);
2363
2364         /* Flags == 0 means only check for existence. */
2365         if (amode) {
2366                 mode = 0;
2367                 if (amode & R_OK)
2368                         mode |= VREAD;
2369                 if (amode & W_OK)
2370                         mode |= VWRITE;
2371                 if (amode & X_OK)
2372                         mode |= VEXEC;
2373                 if ((mode & VWRITE) == 0 ||
2374                     (error = vn_writechk(vp, &nd->nl_nch)) == 0)
2375                         error = VOP_ACCESS_FLAGS(vp, mode, flags, nd->nl_cred);
2376
2377                 /*
2378                  * If the file handle is stale we have to re-resolve the
2379                  * entry.  This is a hack at the moment.
2380                  */
2381                 if (error == ESTALE) {
2382                         vput(vp);
2383                         cache_setunresolved(&nd->nl_nch);
2384                         error = cache_resolve(&nd->nl_nch, nd->nl_cred);
2385                         if (error == 0) {
2386                                 vp = NULL;
2387                                 goto retry;
2388                         }
2389                         return(error);
2390                 }
2391         }
2392         vput(vp);
2393         return (error);
2394 }
2395
2396 /*
2397  * access_args(char *path, int flags)
2398  *
2399  * Check access permissions.
2400  */
2401 int
2402 sys_access(struct access_args *uap)
2403 {
2404         struct nlookupdata nd;
2405         int error;
2406
2407         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2408         if (error == 0)
2409                 error = kern_access(&nd, uap->flags, 0);
2410         nlookup_done(&nd);
2411         return (error);
2412 }
2413
2414
2415 /*
2416  * faccessat_args(int fd, char *path, int amode, int flags)
2417  *
2418  * Check access permissions.
2419  */
2420 int
2421 sys_faccessat(struct faccessat_args *uap)
2422 {
2423         struct nlookupdata nd;
2424         struct file *fp;
2425         int error;
2426
2427         error = nlookup_init_at(&nd, &fp, uap->fd, uap->path, UIO_USERSPACE,
2428                                 NLC_FOLLOW);
2429         if (error == 0)
2430                 error = kern_access(&nd, uap->amode, uap->flags);
2431         nlookup_done_at(&nd, fp);
2432         return (error);
2433 }
2434
2435
2436 int
2437 kern_stat(struct nlookupdata *nd, struct stat *st)
2438 {
2439         int error;
2440         struct vnode *vp;
2441         thread_t td;
2442
2443         if ((error = nlookup(nd)) != 0)
2444                 return (error);
2445 again:
2446         if ((vp = nd->nl_nch.ncp->nc_vp) == NULL)
2447                 return (ENOENT);
2448
2449         td = curthread;
2450         if ((error = vget(vp, LK_SHARED)) != 0)
2451                 return (error);
2452         error = vn_stat(vp, st, nd->nl_cred);
2453
2454         /*
2455          * If the file handle is stale we have to re-resolve the entry.  This
2456          * is a hack at the moment.
2457          */
2458         if (error == ESTALE) {
2459                 vput(vp);
2460                 cache_setunresolved(&nd->nl_nch);
2461                 error = cache_resolve(&nd->nl_nch, nd->nl_cred);
2462                 if (error == 0)
2463                         goto again;
2464         } else {
2465                 vput(vp);
2466         }
2467         return (error);
2468 }
2469
2470 /*
2471  * stat_args(char *path, struct stat *ub)
2472  *
2473  * Get file status; this version follows links.
2474  */
2475 int
2476 sys_stat(struct stat_args *uap)
2477 {
2478         struct nlookupdata nd;
2479         struct stat st;
2480         int error;
2481
2482         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2483         if (error == 0) {
2484                 error = kern_stat(&nd, &st);
2485                 if (error == 0)
2486                         error = copyout(&st, uap->ub, sizeof(*uap->ub));
2487         }
2488         nlookup_done(&nd);
2489         return (error);
2490 }
2491
2492 /*
2493  * lstat_args(char *path, struct stat *ub)
2494  *
2495  * Get file status; this version does not follow links.
2496  */
2497 int
2498 sys_lstat(struct lstat_args *uap)
2499 {
2500         struct nlookupdata nd;
2501         struct stat st;
2502         int error;
2503
2504         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2505         if (error == 0) {
2506                 error = kern_stat(&nd, &st);
2507                 if (error == 0)
2508                         error = copyout(&st, uap->ub, sizeof(*uap->ub));
2509         }
2510         nlookup_done(&nd);
2511         return (error);
2512 }
2513
2514 /*
2515  * fstatat_args(int fd, char *path, struct stat *sb, int flags)
2516  *
2517  * Get status of file pointed to by fd/path.
2518  */
2519 int
2520 sys_fstatat(struct fstatat_args *uap)
2521 {
2522         struct nlookupdata nd;
2523         struct stat st;
2524         int error;
2525         int flags;
2526         struct file *fp;
2527
2528         if (uap->flags & ~AT_SYMLINK_NOFOLLOW)
2529                 return (EINVAL);
2530
2531         flags = (uap->flags & AT_SYMLINK_NOFOLLOW) ? 0 : NLC_FOLLOW;
2532
2533         error = nlookup_init_at(&nd, &fp, uap->fd, uap->path,
2534                                 UIO_USERSPACE, flags);
2535         if (error == 0) {
2536                 error = kern_stat(&nd, &st);
2537                 if (error == 0)
2538                         error = copyout(&st, uap->sb, sizeof(*uap->sb));
2539         }
2540         nlookup_done_at(&nd, fp);
2541         return (error);
2542 }
2543
2544 /*
2545  * pathconf_Args(char *path, int name)
2546  *
2547  * Get configurable pathname variables.
2548  */
2549 /* ARGSUSED */
2550 int
2551 sys_pathconf(struct pathconf_args *uap)
2552 {
2553         struct nlookupdata nd;
2554         struct vnode *vp;
2555         int error;
2556
2557         vp = NULL;
2558         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2559         if (error == 0)
2560                 error = nlookup(&nd);
2561         if (error == 0)
2562                 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
2563         nlookup_done(&nd);
2564         if (error == 0) {
2565                 error = VOP_PATHCONF(vp, uap->name, &uap->sysmsg_reg);
2566                 vput(vp);
2567         }
2568         return (error);
2569 }
2570
2571 /*
2572  * XXX: daver
2573  * kern_readlink isn't properly split yet.  There is a copyin burried
2574  * in VOP_READLINK().
2575  */
2576 int
2577 kern_readlink(struct nlookupdata *nd, char *buf, int count, int *res)
2578 {
2579         struct thread *td = curthread;
2580         struct proc *p = td->td_proc;
2581         struct vnode *vp;
2582         struct iovec aiov;
2583         struct uio auio;
2584         int error;
2585
2586         if ((error = nlookup(nd)) != 0)
2587                 return (error);
2588         error = cache_vget(&nd->nl_nch, nd->nl_cred, LK_EXCLUSIVE, &vp);
2589         if (error)
2590                 return (error);
2591         if (vp->v_type != VLNK) {
2592                 error = EINVAL;
2593         } else {
2594                 aiov.iov_base = buf;
2595                 aiov.iov_len = count;
2596                 auio.uio_iov = &aiov;
2597                 auio.uio_iovcnt = 1;
2598                 auio.uio_offset = 0;
2599                 auio.uio_rw = UIO_READ;
2600                 auio.uio_segflg = UIO_USERSPACE;
2601                 auio.uio_td = td;
2602                 auio.uio_resid = count;
2603                 error = VOP_READLINK(vp, &auio, p->p_ucred);
2604         }
2605         vput(vp);
2606         *res = count - auio.uio_resid;
2607         return (error);
2608 }
2609
2610 /*
2611  * readlink_args(char *path, char *buf, int count)
2612  *
2613  * Return target name of a symbolic link.
2614  */
2615 int
2616 sys_readlink(struct readlink_args *uap)
2617 {
2618         struct nlookupdata nd;
2619         int error;
2620
2621         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2622         if (error == 0) {
2623                 error = kern_readlink(&nd, uap->buf, uap->count,
2624                                         &uap->sysmsg_result);
2625         }
2626         nlookup_done(&nd);
2627         return (error);
2628 }
2629
2630 static int
2631 setfflags(struct vnode *vp, int flags)
2632 {
2633         struct thread *td = curthread;
2634         struct proc *p = td->td_proc;
2635         int error;
2636         struct vattr vattr;
2637
2638         /*
2639          * Prevent non-root users from setting flags on devices.  When
2640          * a device is reused, users can retain ownership of the device
2641          * if they are allowed to set flags and programs assume that
2642          * chown can't fail when done as root.
2643          */
2644         if ((vp->v_type == VCHR || vp->v_type == VBLK) &&
2645             ((error = priv_check_cred(p->p_ucred, PRIV_VFS_CHFLAGS_DEV, 0)) != 0))
2646                 return (error);
2647
2648         /*
2649          * note: vget is required for any operation that might mod the vnode
2650          * so VINACTIVE is properly cleared.
2651          */
2652         if ((error = vget(vp, LK_EXCLUSIVE)) == 0) {
2653                 VATTR_NULL(&vattr);
2654                 vattr.va_flags = flags;
2655                 error = VOP_SETATTR(vp, &vattr, p->p_ucred);
2656                 vput(vp);
2657         }
2658         return (error);
2659 }
2660
2661 /*
2662  * chflags(char *path, int flags)
2663  *
2664  * Change flags of a file given a path name.
2665  */
2666 /* ARGSUSED */
2667 int
2668 sys_chflags(struct chflags_args *uap)
2669 {
2670         struct nlookupdata nd;
2671         struct vnode *vp;
2672         int error;
2673
2674         vp = NULL;
2675         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2676         if (error == 0)
2677                 error = nlookup(&nd);
2678         if (error == 0)
2679                 error = ncp_writechk(&nd.nl_nch);
2680         if (error == 0)
2681                 error = cache_vref(&nd.nl_nch, nd.nl_cred, &vp);
2682         nlookup_done(&nd);
2683         if (error == 0) {
2684                 error = setfflags(vp, uap->flags);
2685                 vrele(vp);
2686         }
2687         return (error);
2688 }
2689
2690 /*
2691  * lchflags(char *path, int flags)
2692  *
2693  * Change flags of a file given a path name, but don't follow symlinks.
2694  */
2695 /* ARGSUSED */
2696 int
2697 sys_lchflags(struct lchflags_args *uap)
2698 {
2699         struct nlookupdata nd;
2700         struct vnode *vp;
2701         int error;
2702
2703         vp = NULL;
2704         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2705         if (error == 0)
2706                 error = nlookup(&nd);
2707         if (error == 0)
2708                 error = ncp_writechk(&nd.nl_nch);
2709         if (error == 0)
2710                 error = cache_vref(&nd.nl_nch, nd.nl_cred, &vp);
2711         nlookup_done(&nd);
2712         if (error == 0) {
2713                 error = setfflags(vp, uap->flags);
2714                 vrele(vp);
2715         }
2716         return (error);
2717 }
2718
2719 /*
2720  * fchflags_args(int fd, int flags)
2721  *
2722  * Change flags of a file given a file descriptor.
2723  */
2724 /* ARGSUSED */
2725 int
2726 sys_fchflags(struct fchflags_args *uap)
2727 {
2728         struct thread *td = curthread;
2729         struct proc *p = td->td_proc;
2730         struct file *fp;
2731         int error;
2732
2733         if ((error = holdvnode(p->p_fd, uap->fd, &fp)) != 0)
2734                 return (error);
2735         if (fp->f_nchandle.ncp)
2736                 error = ncp_writechk(&fp->f_nchandle);
2737         if (error == 0)
2738                 error = setfflags((struct vnode *) fp->f_data, uap->flags);
2739         fdrop(fp);
2740         return (error);
2741 }
2742
2743 static int
2744 setfmode(struct vnode *vp, int mode)
2745 {
2746         struct thread *td = curthread;
2747         struct proc *p = td->td_proc;
2748         int error;
2749         struct vattr vattr;
2750
2751         /*
2752          * note: vget is required for any operation that might mod the vnode
2753          * so VINACTIVE is properly cleared.
2754          */
2755         if ((error = vget(vp, LK_EXCLUSIVE)) == 0) {
2756                 VATTR_NULL(&vattr);
2757                 vattr.va_mode = mode & ALLPERMS;
2758                 error = VOP_SETATTR(vp, &vattr, p->p_ucred);
2759                 vput(vp);
2760         }
2761         return error;
2762 }
2763
2764 int
2765 kern_chmod(struct nlookupdata *nd, int mode)
2766 {
2767         struct vnode *vp;
2768         int error;
2769
2770         if ((error = nlookup(nd)) != 0)
2771                 return (error);
2772         if ((error = cache_vref(&nd->nl_nch, nd->nl_cred, &vp)) != 0)
2773                 return (error);
2774         if ((error = ncp_writechk(&nd->nl_nch)) == 0)
2775                 error = setfmode(vp, mode);
2776         vrele(vp);
2777         return (error);
2778 }
2779
2780 /*
2781  * chmod_args(char *path, int mode)
2782  *
2783  * Change mode of a file given path name.
2784  */
2785 /* ARGSUSED */
2786 int
2787 sys_chmod(struct chmod_args *uap)
2788 {
2789         struct nlookupdata nd;
2790         int error;
2791
2792         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2793         if (error == 0)
2794                 error = kern_chmod(&nd, uap->mode);
2795         nlookup_done(&nd);
2796         return (error);
2797 }
2798
2799 /*
2800  * lchmod_args(char *path, int mode)
2801  *
2802  * Change mode of a file given path name (don't follow links.)
2803  */
2804 /* ARGSUSED */
2805 int
2806 sys_lchmod(struct lchmod_args *uap)
2807 {
2808         struct nlookupdata nd;
2809         int error;
2810
2811         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2812         if (error == 0)
2813                 error = kern_chmod(&nd, uap->mode);
2814         nlookup_done(&nd);
2815         return (error);
2816 }
2817
2818 /*
2819  * fchmod_args(int fd, int mode)
2820  *
2821  * Change mode of a file given a file descriptor.
2822  */
2823 /* ARGSUSED */
2824 int
2825 sys_fchmod(struct fchmod_args *uap)
2826 {
2827         struct thread *td = curthread;
2828         struct proc *p = td->td_proc;
2829         struct file *fp;
2830         int error;
2831
2832         if ((error = holdvnode(p->p_fd, uap->fd, &fp)) != 0)
2833                 return (error);
2834         if (fp->f_nchandle.ncp)
2835                 error = ncp_writechk(&fp->f_nchandle);
2836         if (error == 0)
2837                 error = setfmode((struct vnode *)fp->f_data, uap->mode);
2838         fdrop(fp);
2839         return (error);
2840 }
2841
2842 /*
2843  * fchmodat_args(char *path, int mode)
2844  *
2845  * Change mode of a file pointed to by fd/path.
2846  */
2847 int
2848 sys_fchmodat(struct fchmodat_args *uap)
2849 {
2850         struct nlookupdata nd;
2851         struct file *fp;
2852         int error;
2853         int flags;
2854
2855         if (uap->flags & ~AT_SYMLINK_NOFOLLOW)
2856                 return (EINVAL);
2857         flags = (uap->flags & AT_SYMLINK_NOFOLLOW) ? 0 : NLC_FOLLOW;
2858
2859         error = nlookup_init_at(&nd, &fp, uap->fd, uap->path,
2860                                 UIO_USERSPACE, flags);
2861         if (error == 0)
2862                 error = kern_chmod(&nd, uap->mode);
2863         nlookup_done_at(&nd, fp);
2864         return (error);
2865 }
2866
2867 static int
2868 setfown(struct vnode *vp, uid_t uid, gid_t gid)
2869 {
2870         struct thread *td = curthread;
2871         struct proc *p = td->td_proc;
2872         int error;
2873         struct vattr vattr;
2874
2875         /*
2876          * note: vget is required for any operation that might mod the vnode
2877          * so VINACTIVE is properly cleared.
2878          */
2879         if ((error = vget(vp, LK_EXCLUSIVE)) == 0) {
2880                 VATTR_NULL(&vattr);
2881                 vattr.va_uid = uid;
2882                 vattr.va_gid = gid;
2883                 error = VOP_SETATTR(vp, &vattr, p->p_ucred);
2884                 vput(vp);
2885         }
2886         return error;
2887 }
2888
2889 int
2890 kern_chown(struct nlookupdata *nd, int uid, int gid)
2891 {
2892         struct vnode *vp;
2893         int error;
2894
2895         if ((error = nlookup(nd)) != 0)
2896                 return (error);
2897         if ((error = cache_vref(&nd->nl_nch, nd->nl_cred, &vp)) != 0)
2898                 return (error);
2899         if ((error = ncp_writechk(&nd->nl_nch)) == 0)
2900                 error = setfown(vp, uid, gid);
2901         vrele(vp);
2902         return (error);
2903 }
2904
2905 /*
2906  * chown(char *path, int uid, int gid)
2907  *
2908  * Set ownership given a path name.
2909  */
2910 int
2911 sys_chown(struct chown_args *uap)
2912 {
2913         struct nlookupdata nd;
2914         int error;
2915
2916         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
2917         if (error == 0)
2918                 error = kern_chown(&nd, uap->uid, uap->gid);
2919         nlookup_done(&nd);
2920         return (error);
2921 }
2922
2923 /*
2924  * lchown_args(char *path, int uid, int gid)
2925  *
2926  * Set ownership given a path name, do not cross symlinks.
2927  */
2928 int
2929 sys_lchown(struct lchown_args *uap)
2930 {
2931         struct nlookupdata nd;
2932         int error;
2933
2934         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
2935         if (error == 0)
2936                 error = kern_chown(&nd, uap->uid, uap->gid);
2937         nlookup_done(&nd);
2938         return (error);
2939 }
2940
2941 /*
2942  * fchown_args(int fd, int uid, int gid)
2943  *
2944  * Set ownership given a file descriptor.
2945  */
2946 /* ARGSUSED */
2947 int
2948 sys_fchown(struct fchown_args *uap)
2949 {
2950         struct thread *td = curthread;
2951         struct proc *p = td->td_proc;
2952         struct file *fp;
2953         int error;
2954
2955         if ((error = holdvnode(p->p_fd, uap->fd, &fp)) != 0)
2956                 return (error);
2957         if (fp->f_nchandle.ncp)
2958                 error = ncp_writechk(&fp->f_nchandle);
2959         if (error == 0)
2960                 error = setfown((struct vnode *)fp->f_data, uap->uid, uap->gid);
2961         fdrop(fp);
2962         return (error);
2963 }
2964
2965 /*
2966  * fchownat(int fd, char *path, int uid, int gid, int flags)
2967  *
2968  * Set ownership of file pointed to by fd/path.
2969  */
2970 int
2971 sys_fchownat(struct fchownat_args *uap)
2972 {
2973         struct nlookupdata nd;
2974         struct file *fp;
2975         int error;
2976         int flags;
2977
2978         if (uap->flags & ~AT_SYMLINK_NOFOLLOW)
2979                 return (EINVAL);
2980         flags = (uap->flags & AT_SYMLINK_NOFOLLOW) ? 0 : NLC_FOLLOW;
2981
2982         error = nlookup_init_at(&nd, &fp, uap->fd, uap->path,
2983                                 UIO_USERSPACE, flags);
2984         if (error == 0)
2985                 error = kern_chown(&nd, uap->uid, uap->gid);
2986         nlookup_done_at(&nd, fp);
2987         return (error);
2988 }
2989
2990
2991 static int
2992 getutimes(const struct timeval *tvp, struct timespec *tsp)
2993 {
2994         struct timeval tv[2];
2995
2996         if (tvp == NULL) {
2997                 microtime(&tv[0]);
2998                 TIMEVAL_TO_TIMESPEC(&tv[0], &tsp[0]);
2999                 tsp[1] = tsp[0];
3000         } else {
3001                 TIMEVAL_TO_TIMESPEC(&tvp[0], &tsp[0]);
3002                 TIMEVAL_TO_TIMESPEC(&tvp[1], &tsp[1]);
3003         }
3004         return 0;
3005 }
3006
3007 static int
3008 setutimes(struct vnode *vp, struct vattr *vattr,
3009           const struct timespec *ts, int nullflag)
3010 {
3011         struct thread *td = curthread;
3012         struct proc *p = td->td_proc;
3013         int error;
3014
3015         VATTR_NULL(vattr);
3016         vattr->va_atime = ts[0];
3017         vattr->va_mtime = ts[1];
3018         if (nullflag)
3019                 vattr->va_vaflags |= VA_UTIMES_NULL;
3020         error = VOP_SETATTR(vp, vattr, p->p_ucred);
3021
3022         return error;
3023 }
3024
3025 int
3026 kern_utimes(struct nlookupdata *nd, struct timeval *tptr)
3027 {
3028         struct timespec ts[2];
3029         struct vnode *vp;
3030         struct vattr vattr;
3031         int error;
3032
3033         if ((error = getutimes(tptr, ts)) != 0)
3034                 return (error);
3035
3036         /*
3037          * NOTE: utimes() succeeds for the owner even if the file
3038          * is not user-writable.
3039          */
3040         nd->nl_flags |= NLC_OWN | NLC_WRITE;
3041
3042         if ((error = nlookup(nd)) != 0)
3043                 return (error);
3044         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
3045                 return (error);
3046         if ((error = cache_vref(&nd->nl_nch, nd->nl_cred, &vp)) != 0)
3047                 return (error);
3048
3049         /*
3050          * note: vget is required for any operation that might mod the vnode
3051          * so VINACTIVE is properly cleared.
3052          */
3053         if ((error = vn_writechk(vp, &nd->nl_nch)) == 0) {
3054                 error = vget(vp, LK_EXCLUSIVE);
3055                 if (error == 0) {
3056                         error = setutimes(vp, &vattr, ts, (tptr == NULL));
3057                         vput(vp);
3058                 }
3059         }
3060         vrele(vp);
3061         return (error);
3062 }
3063
3064 /*
3065  * utimes_args(char *path, struct timeval *tptr)
3066  *
3067  * Set the access and modification times of a file.
3068  */
3069 int
3070 sys_utimes(struct utimes_args *uap)
3071 {
3072         struct timeval tv[2];
3073         struct nlookupdata nd;
3074         int error;
3075
3076         if (uap->tptr) {
3077                 error = copyin(uap->tptr, tv, sizeof(tv));
3078                 if (error)
3079                         return (error);
3080         }
3081         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
3082         if (error == 0)
3083                 error = kern_utimes(&nd, uap->tptr ? tv : NULL);
3084         nlookup_done(&nd);
3085         return (error);
3086 }
3087
3088 /*
3089  * lutimes_args(char *path, struct timeval *tptr)
3090  *
3091  * Set the access and modification times of a file.
3092  */
3093 int
3094 sys_lutimes(struct lutimes_args *uap)
3095 {
3096         struct timeval tv[2];
3097         struct nlookupdata nd;
3098         int error;
3099
3100         if (uap->tptr) {
3101                 error = copyin(uap->tptr, tv, sizeof(tv));
3102                 if (error)
3103                         return (error);
3104         }
3105         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
3106         if (error == 0)
3107                 error = kern_utimes(&nd, uap->tptr ? tv : NULL);
3108         nlookup_done(&nd);
3109         return (error);
3110 }
3111
3112 /*
3113  * Set utimes on a file descriptor.  The creds used to open the
3114  * file are used to determine whether the operation is allowed
3115  * or not.
3116  */
3117 int
3118 kern_futimes(int fd, struct timeval *tptr)
3119 {
3120         struct thread *td = curthread;
3121         struct proc *p = td->td_proc;
3122         struct timespec ts[2];
3123         struct file *fp;
3124         struct vnode *vp;
3125         struct vattr vattr;
3126         int error;
3127
3128         error = getutimes(tptr, ts);
3129         if (error)
3130                 return (error);
3131         if ((error = holdvnode(p->p_fd, fd, &fp)) != 0)
3132                 return (error);
3133         if (fp->f_nchandle.ncp)
3134                 error = ncp_writechk(&fp->f_nchandle);
3135         if (error == 0) {
3136                 vp = fp->f_data;
3137                 error = vget(vp, LK_EXCLUSIVE);
3138                 if (error == 0) {
3139                         error = VOP_GETATTR(vp, &vattr);
3140                         if (error == 0) {
3141                                 error = naccess_va(&vattr, NLC_OWN | NLC_WRITE,
3142                                                    fp->f_cred);
3143                         }
3144                         if (error == 0) {
3145                                 error = setutimes(vp, &vattr, ts,
3146                                                   (tptr == NULL));
3147                         }
3148                         vput(vp);
3149                 }
3150         }
3151         fdrop(fp);
3152         return (error);
3153 }
3154
3155 /*
3156  * futimes_args(int fd, struct timeval *tptr)
3157  *
3158  * Set the access and modification times of a file.
3159  */
3160 int
3161 sys_futimes(struct futimes_args *uap)
3162 {
3163         struct timeval tv[2];
3164         int error;
3165
3166         if (uap->tptr) {
3167                 error = copyin(uap->tptr, tv, sizeof(tv));
3168                 if (error)
3169                         return (error);
3170         }
3171
3172         error = kern_futimes(uap->fd, uap->tptr ? tv : NULL);
3173
3174         return (error);
3175 }
3176
3177 int
3178 kern_truncate(struct nlookupdata *nd, off_t length)
3179 {
3180         struct vnode *vp;
3181         struct vattr vattr;
3182         int error;
3183
3184         if (length < 0)
3185                 return(EINVAL);
3186         nd->nl_flags |= NLC_WRITE | NLC_TRUNCATE;
3187         if ((error = nlookup(nd)) != 0)
3188                 return (error);
3189         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
3190                 return (error);
3191         if ((error = cache_vref(&nd->nl_nch, nd->nl_cred, &vp)) != 0)
3192                 return (error);
3193         if ((error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY)) != 0) {
3194                 vrele(vp);
3195                 return (error);
3196         }
3197         if (vp->v_type == VDIR) {
3198                 error = EISDIR;
3199         } else if ((error = vn_writechk(vp, &nd->nl_nch)) == 0) {
3200                 VATTR_NULL(&vattr);
3201                 vattr.va_size = length;
3202                 error = VOP_SETATTR(vp, &vattr, nd->nl_cred);
3203         }
3204         vput(vp);
3205         return (error);
3206 }
3207
3208 /*
3209  * truncate(char *path, int pad, off_t length)
3210  *
3211  * Truncate a file given its path name.
3212  */
3213 int
3214 sys_truncate(struct truncate_args *uap)
3215 {
3216         struct nlookupdata nd;
3217         int error;
3218
3219         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
3220         if (error == 0)
3221                 error = kern_truncate(&nd, uap->length);
3222         nlookup_done(&nd);
3223         return error;
3224 }
3225
3226 int
3227 kern_ftruncate(int fd, off_t length)
3228 {
3229         struct thread *td = curthread;
3230         struct proc *p = td->td_proc;
3231         struct vattr vattr;
3232         struct vnode *vp;
3233         struct file *fp;
3234         int error;
3235
3236         if (length < 0)
3237                 return(EINVAL);
3238         if ((error = holdvnode(p->p_fd, fd, &fp)) != 0)
3239                 return (error);
3240         if (fp->f_nchandle.ncp) {
3241                 error = ncp_writechk(&fp->f_nchandle);
3242                 if (error)
3243                         goto done;
3244         }
3245         if ((fp->f_flag & FWRITE) == 0) {
3246                 error = EINVAL;
3247                 goto done;
3248         }
3249         if (fp->f_flag & FAPPENDONLY) { /* inode was set s/uapnd */
3250                 error = EINVAL;
3251                 goto done;
3252         }
3253         vp = (struct vnode *)fp->f_data;
3254         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3255         if (vp->v_type == VDIR) {
3256                 error = EISDIR;
3257         } else if ((error = vn_writechk(vp, NULL)) == 0) {
3258                 VATTR_NULL(&vattr);
3259                 vattr.va_size = length;
3260                 error = VOP_SETATTR(vp, &vattr, fp->f_cred);
3261         }
3262         vn_unlock(vp);
3263 done:
3264         fdrop(fp);
3265         return (error);
3266 }
3267
3268 /*
3269  * ftruncate_args(int fd, int pad, off_t length)
3270  *
3271  * Truncate a file given a file descriptor.
3272  */
3273 int
3274 sys_ftruncate(struct ftruncate_args *uap)
3275 {
3276         int error;
3277
3278         error = kern_ftruncate(uap->fd, uap->length);
3279
3280         return (error);
3281 }
3282
3283 /*
3284  * fsync(int fd)
3285  *
3286  * Sync an open file.
3287  */
3288 /* ARGSUSED */
3289 int
3290 sys_fsync(struct fsync_args *uap)
3291 {
3292         struct thread *td = curthread;
3293         struct proc *p = td->td_proc;
3294         struct vnode *vp;
3295         struct file *fp;
3296         vm_object_t obj;
3297         int error;
3298
3299         if ((error = holdvnode(p->p_fd, uap->fd, &fp)) != 0)
3300                 return (error);
3301         vp = (struct vnode *)fp->f_data;
3302         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3303         if ((obj = vp->v_object) != NULL)
3304                 vm_object_page_clean(obj, 0, 0, 0);
3305         error = VOP_FSYNC(vp, MNT_WAIT, VOP_FSYNC_SYSCALL);
3306         if (error == 0 && vp->v_mount)
3307                 error = buf_fsync(vp);
3308         vn_unlock(vp);
3309         fdrop(fp);
3310         return (error);
3311 }
3312
3313 int
3314 kern_rename(struct nlookupdata *fromnd, struct nlookupdata *tond)
3315 {
3316         struct nchandle fnchd;
3317         struct nchandle tnchd;
3318         struct namecache *ncp;
3319         struct vnode *fdvp;
3320         struct vnode *tdvp;
3321         struct mount *mp;
3322         int error;
3323
3324         bwillinode(1);
3325         fromnd->nl_flags |= NLC_REFDVP | NLC_RENAME_SRC;
3326         if ((error = nlookup(fromnd)) != 0)
3327                 return (error);
3328         if ((fnchd.ncp = fromnd->nl_nch.ncp->nc_parent) == NULL)
3329                 return (ENOENT);
3330         fnchd.mount = fromnd->nl_nch.mount;
3331         cache_hold(&fnchd);
3332
3333         /*
3334          * unlock the source nch so we can lookup the target nch without
3335          * deadlocking.  The target may or may not exist so we do not check
3336          * for a target vp like kern_mkdir() and other creation functions do.
3337          *
3338          * The source and target directories are ref'd and rechecked after
3339          * everything is relocked to determine if the source or target file
3340          * has been renamed.
3341          */
3342         KKASSERT(fromnd->nl_flags & NLC_NCPISLOCKED);
3343         fromnd->nl_flags &= ~NLC_NCPISLOCKED;
3344         cache_unlock(&fromnd->nl_nch);
3345
3346         tond->nl_flags |= NLC_RENAME_DST | NLC_REFDVP;
3347         if ((error = nlookup(tond)) != 0) {
3348                 cache_drop(&fnchd);
3349                 return (error);
3350         }
3351         if ((tnchd.ncp = tond->nl_nch.ncp->nc_parent) == NULL) {
3352                 cache_drop(&fnchd);
3353                 return (ENOENT);
3354         }
3355         tnchd.mount = tond->nl_nch.mount;
3356         cache_hold(&tnchd);
3357
3358         /*
3359          * If the source and target are the same there is nothing to do
3360          */
3361         if (fromnd->nl_nch.ncp == tond->nl_nch.ncp) {
3362                 cache_drop(&fnchd);
3363                 cache_drop(&tnchd);
3364                 return (0);
3365         }
3366
3367         /*
3368          * Mount points cannot be renamed or overwritten
3369          */
3370         if ((fromnd->nl_nch.ncp->nc_flag | tond->nl_nch.ncp->nc_flag) &
3371             NCF_ISMOUNTPT
3372         ) {
3373                 cache_drop(&fnchd);
3374                 cache_drop(&tnchd);
3375                 return (EINVAL);
3376         }
3377
3378         /*
3379          * relock the source ncp.  NOTE AFTER RELOCKING: the source ncp
3380          * may have become invalid while it was unlocked, nc_vp and nc_mount
3381          * could be NULL.
3382          */
3383         if (cache_lock_nonblock(&fromnd->nl_nch) == 0) {
3384                 cache_resolve(&fromnd->nl_nch, fromnd->nl_cred);
3385         } else if (fromnd->nl_nch.ncp > tond->nl_nch.ncp) {
3386                 cache_lock(&fromnd->nl_nch);
3387                 cache_resolve(&fromnd->nl_nch, fromnd->nl_cred);
3388         } else {
3389                 cache_unlock(&tond->nl_nch);
3390                 cache_lock(&fromnd->nl_nch);
3391                 cache_resolve(&fromnd->nl_nch, fromnd->nl_cred);
3392                 cache_lock(&tond->nl_nch);
3393                 cache_resolve(&tond->nl_nch, tond->nl_cred);
3394         }
3395         fromnd->nl_flags |= NLC_NCPISLOCKED;
3396
3397         /*
3398          * make sure the parent directories linkages are the same
3399          */
3400         if (fnchd.ncp != fromnd->nl_nch.ncp->nc_parent ||
3401             tnchd.ncp != tond->nl_nch.ncp->nc_parent) {
3402                 cache_drop(&fnchd);
3403                 cache_drop(&tnchd);
3404                 return (ENOENT);
3405         }
3406
3407         /*
3408          * Both the source and target must be within the same filesystem and
3409          * in the same filesystem as their parent directories within the
3410          * namecache topology.
3411          *
3412          * NOTE: fromnd's nc_mount or nc_vp could be NULL.
3413          */
3414         mp = fnchd.mount;
3415         if (mp != tnchd.mount || mp != fromnd->nl_nch.mount ||
3416             mp != tond->nl_nch.mount) {
3417                 cache_drop(&fnchd);
3418                 cache_drop(&tnchd);
3419                 return (EXDEV);
3420         }
3421
3422         /*
3423          * Make sure the mount point is writable
3424          */
3425         if ((error = ncp_writechk(&tond->nl_nch)) != 0) {
3426                 cache_drop(&fnchd);
3427                 cache_drop(&tnchd);
3428                 return (error);
3429         }
3430
3431         /*
3432          * If the target exists and either the source or target is a directory,
3433          * then both must be directories.
3434          *
3435          * Due to relocking of the source, fromnd->nl_nch.ncp->nc_vp might h
3436          * have become NULL.
3437          */
3438         if (tond->nl_nch.ncp->nc_vp) {
3439                 if (fromnd->nl_nch.ncp->nc_vp == NULL) {
3440                         error = ENOENT;
3441                 } else if (fromnd->nl_nch.ncp->nc_vp->v_type == VDIR) {
3442                         if (tond->nl_nch.ncp->nc_vp->v_type != VDIR)
3443                                 error = ENOTDIR;
3444                 } else if (tond->nl_nch.ncp->nc_vp->v_type == VDIR) {
3445                         error = EISDIR;
3446                 }
3447         }
3448
3449         /*
3450          * You cannot rename a source into itself or a subdirectory of itself.
3451          * We check this by travsersing the target directory upwards looking
3452          * for a match against the source.
3453          */
3454         if (error == 0) {
3455                 for (ncp = tnchd.ncp; ncp; ncp = ncp->nc_parent) {
3456                         if (fromnd->nl_nch.ncp == ncp) {
3457                                 error = EINVAL;
3458                                 break;
3459                         }
3460                 }
3461         }
3462
3463         cache_drop(&fnchd);
3464         cache_drop(&tnchd);
3465
3466         /*
3467          * Even though the namespaces are different, they may still represent
3468          * hardlinks to the same file.  The filesystem might have a hard time
3469          * with this so we issue a NREMOVE of the source instead of a NRENAME
3470          * when we detect the situation.
3471          */
3472         if (error == 0) {
3473                 fdvp = fromnd->nl_dvp;
3474                 tdvp = tond->nl_dvp;
3475                 if (fdvp == NULL || tdvp == NULL) {
3476                         error = EPERM;
3477                 } else if (fromnd->nl_nch.ncp->nc_vp == tond->nl_nch.ncp->nc_vp) {
3478                         error = VOP_NREMOVE(&fromnd->nl_nch, fdvp,
3479                                             fromnd->nl_cred);
3480                 } else {
3481                         error = VOP_NRENAME(&fromnd->nl_nch, &tond->nl_nch,
3482                                             fdvp, tdvp, tond->nl_cred);
3483                 }
3484         }
3485         return (error);
3486 }
3487
3488 /*
3489  * rename_args(char *from, char *to)
3490  *
3491  * Rename files.  Source and destination must either both be directories,
3492  * or both not be directories.  If target is a directory, it must be empty.
3493  */
3494 int
3495 sys_rename(struct rename_args *uap)
3496 {
3497         struct nlookupdata fromnd, tond;
3498         int error;
3499
3500         error = nlookup_init(&fromnd, uap->from, UIO_USERSPACE, 0);
3501         if (error == 0) {
3502                 error = nlookup_init(&tond, uap->to, UIO_USERSPACE, 0);
3503                 if (error == 0)
3504                         error = kern_rename(&fromnd, &tond);
3505                 nlookup_done(&tond);
3506         }
3507         nlookup_done(&fromnd);
3508         return (error);
3509 }
3510
3511 int
3512 kern_mkdir(struct nlookupdata *nd, int mode)
3513 {
3514         struct thread *td = curthread;
3515         struct proc *p = td->td_proc;
3516         struct vnode *vp;
3517         struct vattr vattr;
3518         int error;
3519
3520         bwillinode(1);
3521         nd->nl_flags |= NLC_WILLBEDIR | NLC_CREATE | NLC_REFDVP;
3522         if ((error = nlookup(nd)) != 0)
3523                 return (error);
3524
3525         if (nd->nl_nch.ncp->nc_vp)
3526                 return (EEXIST);
3527         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
3528                 return (error);
3529         VATTR_NULL(&vattr);
3530         vattr.va_type = VDIR;
3531         vattr.va_mode = (mode & ACCESSPERMS) &~ p->p_fd->fd_cmask;
3532
3533         vp = NULL;
3534         error = VOP_NMKDIR(&nd->nl_nch, nd->nl_dvp, &vp, p->p_ucred, &vattr);
3535         if (error == 0)
3536                 vput(vp);
3537         return (error);
3538 }
3539
3540 /*
3541  * mkdir_args(char *path, int mode)
3542  *
3543  * Make a directory file.
3544  */
3545 /* ARGSUSED */
3546 int
3547 sys_mkdir(struct mkdir_args *uap)
3548 {
3549         struct nlookupdata nd;
3550         int error;
3551
3552         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
3553         if (error == 0)
3554                 error = kern_mkdir(&nd, uap->mode);
3555         nlookup_done(&nd);
3556         return (error);
3557 }
3558
3559 int
3560 kern_rmdir(struct nlookupdata *nd)
3561 {
3562         int error;
3563
3564         bwillinode(1);
3565         nd->nl_flags |= NLC_DELETE | NLC_REFDVP;
3566         if ((error = nlookup(nd)) != 0)
3567                 return (error);
3568
3569         /*
3570          * Do not allow directories representing mount points to be
3571          * deleted, even if empty.  Check write perms on mount point
3572          * in case the vnode is aliased (aka nullfs).
3573          */
3574         if (nd->nl_nch.ncp->nc_flag & (NCF_ISMOUNTPT))
3575                 return (EINVAL);
3576         if ((error = ncp_writechk(&nd->nl_nch)) != 0)
3577                 return (error);
3578         error = VOP_NRMDIR(&nd->nl_nch, nd->nl_dvp, nd->nl_cred);
3579         return (error);
3580 }
3581
3582 /*
3583  * rmdir_args(char *path)
3584  *
3585  * Remove a directory file.
3586  */
3587 /* ARGSUSED */
3588 int
3589 sys_rmdir(struct rmdir_args *uap)
3590 {
3591         struct nlookupdata nd;
3592         int error;
3593
3594         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, 0);
3595         if (error == 0)
3596                 error = kern_rmdir(&nd);
3597         nlookup_done(&nd);
3598         return (error);
3599 }
3600
3601 int
3602 kern_getdirentries(int fd, char *buf, u_int count, long *basep, int *res,
3603     enum uio_seg direction)
3604 {
3605         struct thread *td = curthread;
3606         struct proc *p = td->td_proc;
3607         struct vnode *vp;
3608         struct file *fp;
3609         struct uio auio;
3610         struct iovec aiov;
3611         off_t loff;
3612         int error, eofflag;
3613
3614         if ((error = holdvnode(p->p_fd, fd, &fp)) != 0)
3615                 return (error);
3616         if ((fp->f_flag & FREAD) == 0) {
3617                 error = EBADF;
3618                 goto done;
3619         }
3620         vp = (struct vnode *)fp->f_data;
3621 unionread:
3622         if (vp->v_type != VDIR) {
3623                 error = EINVAL;
3624                 goto done;
3625         }
3626         aiov.iov_base = buf;
3627         aiov.iov_len = count;
3628         auio.uio_iov = &aiov;
3629         auio.uio_iovcnt = 1;
3630         auio.uio_rw = UIO_READ;
3631         auio.uio_segflg = direction;
3632         auio.uio_td = td;
3633         auio.uio_resid = count;
3634         loff = auio.uio_offset = fp->f_offset;
3635         error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, NULL, NULL);
3636         fp->f_offset = auio.uio_offset;
3637         if (error)
3638                 goto done;
3639         if (count == auio.uio_resid) {
3640                 if (union_dircheckp) {
3641                         error = union_dircheckp(td, &vp, fp);
3642                         if (error == -1)
3643                                 goto unionread;
3644                         if (error)
3645                                 goto done;
3646                 }
3647 #if 0
3648                 if ((vp->v_flag & VROOT) &&
3649                     (vp->v_mount->mnt_flag & MNT_UNION)) {
3650                         struct vnode *tvp = vp;
3651                         vp = vp->v_mount->mnt_vnodecovered;
3652                         vref(vp);
3653                         fp->f_data = vp;
3654                         fp->f_offset = 0;
3655                         vrele(tvp);
3656                         goto unionread;
3657                 }
3658 #endif
3659         }
3660
3661         /*
3662          * WARNING!  *basep may not be wide enough to accomodate the
3663          * seek offset.   XXX should we hack this to return the upper 32 bits
3664          * for offsets greater then 4G?
3665          */
3666         if (basep) {
3667                 *basep = (long)loff;
3668         }
3669         *res = count - auio.uio_resid;
3670 done:
3671         fdrop(fp);
3672         return (error);
3673 }
3674
3675 /*
3676  * getdirentries_args(int fd, char *buf, u_int conut, long *basep)
3677  *
3678  * Read a block of directory entries in a file system independent format.
3679  */
3680 int
3681 sys_getdirentries(struct getdirentries_args *uap)
3682 {
3683         long base;
3684         int error;
3685
3686         error = kern_getdirentries(uap->fd, uap->buf, uap->count, &base,
3687                                    &uap->sysmsg_result, UIO_USERSPACE);
3688
3689         if (error == 0 && uap->basep)
3690                 error = copyout(&base, uap->basep, sizeof(*uap->basep));
3691         return (error);
3692 }
3693
3694 /*
3695  * getdents_args(int fd, char *buf, size_t count)
3696  */
3697 int
3698 sys_getdents(struct getdents_args *uap)
3699 {
3700         int error;
3701
3702         error = kern_getdirentries(uap->fd, uap->buf, uap->count, NULL,
3703             &uap->sysmsg_result, UIO_USERSPACE);
3704
3705         return (error);
3706 }
3707
3708 /*
3709  * umask(int newmask)
3710  *
3711  * Set the mode mask for creation of filesystem nodes.
3712  *
3713  * MP SAFE
3714  */
3715 int
3716 sys_umask(struct umask_args *uap)
3717 {
3718         struct thread *td = curthread;
3719         struct proc *p = td->td_proc;
3720         struct filedesc *fdp;
3721
3722         fdp = p->p_fd;
3723         uap->sysmsg_result = fdp->fd_cmask;
3724         fdp->fd_cmask = uap->newmask & ALLPERMS;
3725         return (0);
3726 }
3727
3728 /*
3729  * revoke(char *path)
3730  *
3731  * Void all references to file by ripping underlying filesystem
3732  * away from vnode.
3733  */
3734 /* ARGSUSED */
3735 int
3736 sys_revoke(struct revoke_args *uap)
3737 {
3738         struct nlookupdata nd;
3739         struct vattr vattr;
3740         struct vnode *vp;
3741         struct ucred *cred;
3742         int error;
3743
3744         vp = NULL;
3745         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
3746         if (error == 0)
3747                 error = nlookup(&nd);
3748         if (error == 0)
3749                 error = cache_vref(&nd.nl_nch, nd.nl_cred, &vp);
3750         cred = crhold(nd.nl_cred);
3751         nlookup_done(&nd);
3752         if (error == 0) {
3753                 if (error == 0)
3754                         error = VOP_GETATTR(vp, &vattr);
3755                 if (error == 0 && cred->cr_uid != vattr.va_uid)
3756                         error = priv_check_cred(cred, PRIV_VFS_REVOKE, 0);
3757                 if (error == 0 && (vp->v_type == VCHR || vp->v_type == VBLK)) {
3758                         if (vcount(vp) > 0)
3759                                 error = vrevoke(vp, cred);
3760                 } else if (error == 0) {
3761                         error = vrevoke(vp, cred);
3762                 }
3763                 vrele(vp);
3764         }
3765         if (cred)
3766                 crfree(cred);
3767         return (error);
3768 }
3769
3770 /*
3771  * getfh_args(char *fname, fhandle_t *fhp)
3772  *
3773  * Get (NFS) file handle
3774  *
3775  * NOTE: We use the fsid of the covering mount, even if it is a nullfs
3776  * mount.  This allows nullfs mounts to be explicitly exported.
3777  *
3778  * WARNING: nullfs mounts of HAMMER PFS ROOTs are safe.
3779  *
3780  *          nullfs mounts of subdirectories are not safe.  That is, it will
3781  *          work, but you do not really have protection against access to
3782  *          the related parent directories.
3783  */
3784 int
3785 sys_getfh(struct getfh_args *uap)
3786 {
3787         struct thread *td = curthread;
3788         struct nlookupdata nd;
3789         fhandle_t fh;
3790         struct vnode *vp;
3791         struct mount *mp;
3792         int error;
3793
3794         /*
3795          * Must be super user
3796          */
3797         if ((error = priv_check(td, PRIV_ROOT)) != 0)
3798                 return (error);
3799
3800         vp = NULL;
3801         error = nlookup_init(&nd, uap->fname, UIO_USERSPACE, NLC_FOLLOW);
3802         if (error == 0)
3803                 error = nlookup(&nd);
3804         if (error == 0)
3805                 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
3806         mp = nd.nl_nch.mount;
3807         nlookup_done(&nd);
3808         if (error == 0) {
3809                 bzero(&fh, sizeof(fh));
3810                 fh.fh_fsid = mp->mnt_stat.f_fsid;
3811                 error = VFS_VPTOFH(vp, &fh.fh_fid);
3812                 vput(vp);
3813                 if (error == 0)
3814                         error = copyout(&fh, uap->fhp, sizeof(fh));
3815         }
3816         return (error);
3817 }
3818
3819 /*
3820  * fhopen_args(const struct fhandle *u_fhp, int flags)
3821  *
3822  * syscall for the rpc.lockd to use to translate a NFS file handle into
3823  * an open descriptor.
3824  *
3825  * warning: do not remove the priv_check() call or this becomes one giant
3826  * security hole.
3827  */
3828 int
3829 sys_fhopen(struct fhopen_args *uap)
3830 {
3831         struct thread *td = curthread;
3832         struct proc *p = td->td_proc;
3833         struct mount *mp;
3834         struct vnode *vp;
3835         struct fhandle fhp;
3836         struct vattr vat;
3837         struct vattr *vap = &vat;
3838         struct flock lf;
3839         int fmode, mode, error, type;
3840         struct file *nfp;
3841         struct file *fp;
3842         int indx;
3843
3844         /*
3845          * Must be super user
3846          */
3847         error = priv_check(td, PRIV_ROOT);
3848         if (error)
3849                 return (error);
3850
3851         fmode = FFLAGS(uap->flags);
3852         /* why not allow a non-read/write open for our lockd? */
3853         if (((fmode & (FREAD | FWRITE)) == 0) || (fmode & O_CREAT))
3854                 return (EINVAL);
3855         error = copyin(uap->u_fhp, &fhp, sizeof(fhp));
3856         if (error)
3857                 return(error);
3858         /* find the mount point */
3859         mp = vfs_getvfs(&fhp.fh_fsid);
3860         if (mp == NULL)
3861                 return (ESTALE);
3862         /* now give me my vnode, it gets returned to me locked */
3863         error = VFS_FHTOVP(mp, NULL, &fhp.fh_fid, &vp);
3864         if (error)
3865                 return (error);
3866         /*
3867          * from now on we have to make sure not
3868          * to forget about the vnode
3869          * any error that causes an abort must vput(vp)
3870          * just set error = err and 'goto bad;'.
3871          */
3872
3873         /*
3874          * from vn_open
3875          */
3876         if (vp->v_type == VLNK) {
3877                 error = EMLINK;
3878                 goto bad;
3879         }
3880         if (vp->v_type == VSOCK) {
3881                 error = EOPNOTSUPP;
3882                 goto bad;
3883         }
3884         mode = 0;
3885         if (fmode & (FWRITE | O_TRUNC)) {
3886                 if (vp->v_type == VDIR) {
3887                         error = EISDIR;
3888                         goto bad;
3889                 }
3890                 error = vn_writechk(vp, NULL);
3891                 if (error)
3892                         goto bad;
3893                 mode |= VWRITE;
3894         }
3895         if (fmode & FREAD)
3896                 mode |= VREAD;
3897         if (mode) {
3898                 error = VOP_ACCESS(vp, mode, p->p_ucred);
3899                 if (error)
3900                         goto bad;
3901         }
3902         if (fmode & O_TRUNC) {
3903                 vn_unlock(vp);                          /* XXX */
3904                 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);   /* XXX */
3905                 VATTR_NULL(vap);
3906                 vap->va_size = 0;
3907                 error = VOP_SETATTR(vp, vap, p->p_ucred);
3908                 if (error)
3909                         goto bad;
3910         }
3911
3912         /*
3913          * VOP_OPEN needs the file pointer so it can potentially override
3914          * it.
3915          *
3916          * WARNING! no f_nchandle will be associated when fhopen()ing a
3917          * directory.  XXX
3918          */
3919         if ((error = falloc(p, &nfp, &indx)) != 0)
3920                 goto bad;
3921         fp = nfp;
3922
3923         error = VOP_OPEN(vp, fmode, p->p_ucred, fp);
3924         if (error) {
3925                 /*
3926                  * setting f_ops this way prevents VOP_CLOSE from being
3927                  * called or fdrop() releasing the vp from v_data.   Since
3928                  * the VOP_OPEN failed we don't want to VOP_CLOSE.
3929                  */
3930                 fp->f_ops = &badfileops;
3931                 fp->f_data = NULL;
3932                 goto bad_drop;
3933         }
3934
3935         /*
3936          * The fp is given its own reference, we still have our ref and lock.
3937          *
3938          * Assert that all regular files must be created with a VM object.
3939          */
3940         if (vp->v_type == VREG && vp->v_object == NULL) {
3941                 kprintf("fhopen: regular file did not have VM object: %p\n", vp);
3942                 goto bad_drop;
3943         }
3944
3945         /*
3946          * The open was successful.  Handle any locking requirements.
3947          */
3948         if (fmode & (O_EXLOCK | O_SHLOCK)) {
3949                 lf.l_whence = SEEK_SET;
3950                 lf.l_start = 0;
3951                 lf.l_len = 0;
3952                 if (fmode & O_EXLOCK)
3953                         lf.l_type = F_WRLCK;
3954                 else
3955                         lf.l_type = F_RDLCK;
3956                 if (fmode & FNONBLOCK)
3957                         type = 0;
3958                 else
3959                         type = F_WAIT;
3960                 vn_unlock(vp);
3961                 if ((error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type)) != 0) {
3962                         /*
3963                          * release our private reference.
3964                          */
3965                         fsetfd(p, NULL, indx);
3966                         fdrop(fp);
3967                         vrele(vp);
3968                         return (error);
3969                 }
3970                 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3971                 fp->f_flag |= FHASLOCK;
3972         }
3973
3974         /*
3975          * Clean up.  Associate the file pointer with the previously
3976          * reserved descriptor and return it.
3977          */
3978         vput(vp);
3979         fsetfd(p, fp, indx);
3980         fdrop(fp);
3981         uap->sysmsg_result = indx;
3982         return (0);
3983
3984 bad_drop:
3985         fsetfd(p, NULL, indx);
3986         fdrop(fp);
3987 bad:
3988         vput(vp);
3989         return (error);
3990 }
3991
3992 /*
3993  * fhstat_args(struct fhandle *u_fhp, struct stat *sb)
3994  */
3995 int
3996 sys_fhstat(struct fhstat_args *uap)
3997 {
3998         struct thread *td = curthread;
3999         struct stat sb;
4000         fhandle_t fh;
4001         struct mount *mp;
4002         struct vnode *vp;
4003         int error;
4004
4005         /*
4006          * Must be super user
4007          */
4008         error = priv_check(td, PRIV_ROOT);
4009         if (error)
4010                 return (error);
4011
4012         error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
4013         if (error)
4014                 return (error);
4015
4016         if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL)
4017                 return (ESTALE);
4018         if ((error = VFS_FHTOVP(mp, NULL, &fh.fh_fid, &vp)))
4019                 return (error);
4020         error = vn_stat(vp, &sb, td->td_proc->p_ucred);
4021         vput(vp);
4022         if (error)
4023                 return (error);
4024         error = copyout(&sb, uap->sb, sizeof(sb));
4025         return (error);
4026 }
4027
4028 /*
4029  * fhstatfs_args(struct fhandle *u_fhp, struct statfs *buf)
4030  */
4031 int
4032 sys_fhstatfs(struct fhstatfs_args *uap)
4033 {
4034         struct thread *td = curthread;
4035         struct proc *p = td->td_proc;
4036         struct statfs *sp;
4037         struct mount *mp;
4038         struct vnode *vp;
4039         struct statfs sb;
4040         char *fullpath, *freepath;
4041         fhandle_t fh;
4042         int error;
4043
4044         /*
4045          * Must be super user
4046          */
4047         if ((error = priv_check(td, PRIV_ROOT)))
4048                 return (error);
4049
4050         if ((error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t))) != 0)
4051                 return (error);
4052
4053         if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL)
4054                 return (ESTALE);
4055
4056         if (p != NULL && !chroot_visible_mnt(mp, p))
4057                 return (ESTALE);
4058
4059         if ((error = VFS_FHTOVP(mp, NULL, &fh.fh_fid, &vp)))
4060                 return (error);
4061         mp = vp->v_mount;
4062         sp = &mp->mnt_stat;
4063         vput(vp);
4064         if ((error = VFS_STATFS(mp, sp, p->p_ucred)) != 0)
4065                 return (error);
4066
4067         error = mount_path(p, mp, &fullpath, &freepath);
4068         if (error)
4069                 return(error);
4070         bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
4071         strlcpy(sp->f_mntonname, fullpath, sizeof(sp->f_mntonname));
4072         kfree(freepath, M_TEMP);
4073
4074         sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
4075         if (priv_check(td, PRIV_ROOT)) {
4076                 bcopy(sp, &sb, sizeof(sb));
4077                 sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
4078                 sp = &sb;
4079         }
4080         return (copyout(sp, uap->buf, sizeof(*sp)));
4081 }
4082
4083 /*
4084  * fhstatvfs_args(struct fhandle *u_fhp, struct statvfs *buf)
4085  */
4086 int
4087 sys_fhstatvfs(struct fhstatvfs_args *uap)
4088 {
4089         struct thread *td = curthread;
4090         struct proc *p = td->td_proc;
4091         struct statvfs *sp;
4092         struct mount *mp;
4093         struct vnode *vp;
4094         fhandle_t fh;
4095         int error;
4096
4097         /*
4098          * Must be super user
4099          */
4100         if ((error = priv_check(td, PRIV_ROOT)))
4101                 return (error);
4102
4103         if ((error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t))) != 0)
4104                 return (error);
4105
4106         if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL)
4107                 return (ESTALE);
4108
4109         if (p != NULL && !chroot_visible_mnt(mp, p))
4110                 return (ESTALE);
4111
4112         if ((error = VFS_FHTOVP(mp, NULL, &fh.fh_fid, &vp)))
4113                 return (error);
4114         mp = vp->v_mount;
4115         sp = &mp->mnt_vstat;
4116         vput(vp);
4117         if ((error = VFS_STATVFS(mp, sp, p->p_ucred)) != 0)
4118                 return (error);
4119
4120         sp->f_flag = 0;
4121         if (mp->mnt_flag & MNT_RDONLY)
4122                 sp->f_flag |= ST_RDONLY;
4123         if (mp->mnt_flag & MNT_NOSUID)
4124                 sp->f_flag |= ST_NOSUID;
4125
4126         return (copyout(sp, uap->buf, sizeof(*sp)));
4127 }
4128
4129
4130 /*
4131  * Syscall to push extended attribute configuration information into the
4132  * VFS.  Accepts a path, which it converts to a mountpoint, as well as
4133  * a command (int cmd), and attribute name and misc data.  For now, the
4134  * attribute name is left in userspace for consumption by the VFS_op.
4135  * It will probably be changed to be copied into sysspace by the
4136  * syscall in the future, once issues with various consumers of the
4137  * attribute code have raised their hands.
4138  *
4139  * Currently this is used only by UFS Extended Attributes.
4140  */
4141 int
4142 sys_extattrctl(struct extattrctl_args *uap)
4143 {
4144         struct nlookupdata nd;
4145         struct mount *mp;
4146         struct vnode *vp;
4147         int error;
4148
4149         vp = NULL;
4150         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
4151         if (error == 0)
4152                 error = nlookup(&nd);
4153         if (error == 0) {
4154                 mp = nd.nl_nch.mount;
4155                 error = VFS_EXTATTRCTL(mp, uap->cmd,
4156                                 uap->attrname, uap->arg,
4157                                 nd.nl_cred);
4158         }
4159         nlookup_done(&nd);
4160         return (error);
4161 }
4162
4163 /*
4164  * Syscall to set a named extended attribute on a file or directory.
4165  * Accepts attribute name, and a uio structure pointing to the data to set.
4166  * The uio is consumed in the style of writev().  The real work happens
4167  * in VOP_SETEXTATTR().
4168  */
4169 int
4170 sys_extattr_set_file(struct extattr_set_file_args *uap)
4171 {
4172         char attrname[EXTATTR_MAXNAMELEN];
4173         struct iovec aiov[UIO_SMALLIOV];
4174         struct iovec *needfree;
4175         struct nlookupdata nd;
4176         struct iovec *iov;
4177         struct vnode *vp;
4178         struct uio auio;
4179         u_int iovlen;
4180         u_int cnt;
4181         int error;
4182         int i;
4183
4184         error = copyin(uap->attrname, attrname, EXTATTR_MAXNAMELEN);
4185         if (error)
4186                 return (error);
4187
4188         vp = NULL;
4189         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
4190         if (error == 0)
4191                 error = nlookup(&nd);
4192         if (error == 0)
4193                 error = ncp_writechk(&nd.nl_nch);
4194         if (error == 0)
4195                 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
4196         if (error) {
4197                 nlookup_done(&nd);
4198                 return (error);
4199         }
4200
4201         needfree = NULL;
4202         iovlen = uap->iovcnt * sizeof(struct iovec);
4203         if (uap->iovcnt > UIO_SMALLIOV) {
4204                 if (uap->iovcnt > UIO_MAXIOV) {
4205                         error = EINVAL;
4206                         goto done;
4207                 }
4208                 MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK);
4209                 needfree = iov;
4210         } else {
4211                 iov = aiov;
4212         }
4213         auio.uio_iov = iov;
4214         auio.uio_iovcnt = uap->iovcnt;
4215         auio.uio_rw = UIO_WRITE;
4216         auio.uio_segflg = UIO_USERSPACE;
4217         auio.uio_td = nd.nl_td;
4218         auio.uio_offset = 0;
4219         if ((error = copyin(uap->iovp, iov, iovlen)))
4220                 goto done;
4221         auio.uio_resid = 0;
4222         for (i = 0; i < uap->iovcnt; i++) {
4223                 if (iov->iov_len > LONG_MAX - auio.uio_resid) {
4224                         error = EINVAL;
4225                         goto done;
4226                 }
4227                 auio.uio_resid += iov->iov_len;
4228                 iov++;
4229         }
4230         cnt = auio.uio_resid;
4231         error = VOP_SETEXTATTR(vp, attrname, &auio, nd.nl_cred);
4232         cnt -= auio.uio_resid;
4233         uap->sysmsg_result = cnt;
4234 done:
4235         vput(vp);
4236         nlookup_done(&nd);
4237         if (needfree)
4238                 FREE(needfree, M_IOV);
4239         return (error);
4240 }
4241
4242 /*
4243  * Syscall to get a named extended attribute on a file or directory.
4244  * Accepts attribute name, and a uio structure pointing to a buffer for the
4245  * data.  The uio is consumed in the style of readv().  The real work
4246  * happens in VOP_GETEXTATTR();
4247  */
4248 int
4249 sys_extattr_get_file(struct extattr_get_file_args *uap)
4250 {
4251         char attrname[EXTATTR_MAXNAMELEN];
4252         struct iovec aiov[UIO_SMALLIOV];
4253         struct iovec *needfree;
4254         struct nlookupdata nd;
4255         struct iovec *iov;
4256         struct vnode *vp;
4257         struct uio auio;
4258         u_int iovlen;
4259         u_int cnt;
4260         int error;
4261         int i;
4262
4263         error = copyin(uap->attrname, attrname, EXTATTR_MAXNAMELEN);
4264         if (error)
4265                 return (error);
4266
4267         vp = NULL;
4268         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
4269         if (error == 0)
4270                 error = nlookup(&nd);
4271         if (error == 0)
4272                 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
4273         if (error) {
4274                 nlookup_done(&nd);
4275                 return (error);
4276         }
4277
4278         iovlen = uap->iovcnt * sizeof (struct iovec);
4279         needfree = NULL;
4280         if (uap->iovcnt > UIO_SMALLIOV) {
4281                 if (uap->iovcnt > UIO_MAXIOV) {
4282                         error = EINVAL;
4283                         goto done;
4284                 }
4285                 MALLOC(iov, struct iovec *, iovlen, M_IOV, M_WAITOK);
4286                 needfree = iov;
4287         } else {
4288                 iov = aiov;
4289         }
4290         auio.uio_iov = iov;
4291         auio.uio_iovcnt = uap->iovcnt;
4292         auio.uio_rw = UIO_READ;
4293         auio.uio_segflg = UIO_USERSPACE;
4294         auio.uio_td = nd.nl_td;
4295         auio.uio_offset = 0;
4296         if ((error = copyin(uap->iovp, iov, iovlen)))
4297                 goto done;
4298         auio.uio_resid = 0;
4299         for (i = 0; i < uap->iovcnt; i++) {
4300                 if (iov->iov_len > LONG_MAX - auio.uio_resid) {
4301                         error = EINVAL;
4302                         goto done;
4303                 }
4304                 auio.uio_resid += iov->iov_len;
4305                 iov++;
4306         }
4307         cnt = auio.uio_resid;
4308         error = VOP_GETEXTATTR(vp, attrname, &auio, nd.nl_cred);
4309         cnt -= auio.uio_resid;
4310         uap->sysmsg_result = cnt;
4311 done:
4312         vput(vp);
4313         nlookup_done(&nd);
4314         if (needfree)
4315                 FREE(needfree, M_IOV);
4316         return(error);
4317 }
4318
4319 /*
4320  * Syscall to delete a named extended attribute from a file or directory.
4321  * Accepts attribute name.  The real work happens in VOP_SETEXTATTR().
4322  */
4323 int
4324 sys_extattr_delete_file(struct extattr_delete_file_args *uap)
4325 {
4326         char attrname[EXTATTR_MAXNAMELEN];
4327         struct nlookupdata nd;
4328         struct vnode *vp;
4329         int error;
4330
4331         error = copyin(uap->attrname, attrname, EXTATTR_MAXNAMELEN);
4332         if (error)
4333                 return(error);
4334
4335         vp = NULL;
4336         error = nlookup_init(&nd, uap->path, UIO_USERSPACE, NLC_FOLLOW);
4337         if (error == 0)
4338                 error = nlookup(&nd);
4339         if (error == 0)
4340                 error = ncp_writechk(&nd.nl_nch);
4341         if (error == 0)
4342                 error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
4343         if (error) {
4344                 nlookup_done(&nd);
4345                 return (error);
4346         }
4347
4348         error = VOP_SETEXTATTR(vp, attrname, NULL, nd.nl_cred);
4349         vput(vp);
4350         nlookup_done(&nd);
4351         return(error);
4352 }
4353
4354 /*
4355  * Determine if the mount is visible to the process.
4356  */
4357 static int
4358 chroot_visible_mnt(struct mount *mp, struct proc *p)
4359 {
4360         struct nchandle nch;
4361
4362         /*
4363          * Traverse from the mount point upwards.  If we hit the process
4364          * root then the mount point is visible to the process.
4365          */
4366         nch = mp->mnt_ncmountpt;
4367         while (nch.ncp) {
4368                 if (nch.mount == p->p_fd->fd_nrdir.mount &&
4369                     nch.ncp == p->p_fd->fd_nrdir.ncp) {
4370                         return(1);
4371                 }
4372                 if (nch.ncp == nch.mount->mnt_ncmountpt.ncp) {
4373                         nch = nch.mount->mnt_ncmounton;
4374                 } else {
4375                         nch.ncp = nch.ncp->nc_parent;
4376                 }
4377         }
4378
4379         /*
4380          * If the mount point is not visible to the process, but the
4381          * process root is in a subdirectory of the mount, return
4382          * TRUE anyway.
4383          */
4384         if (p->p_fd->fd_nrdir.mount == mp)
4385                 return(1);
4386
4387         return(0);
4388 }
4389