ufs_vnops.c

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/*	$NetBSD: ufs_vnops.c,v 1.18 1996/05/11 18:28:04 mycroft Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)ufs_vnops.c	8.14 (Berkeley) 10/26/94
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/resourcevar.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/conf.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/dirent.h>
#include <sys/lockf.h>

#include <vm/vm.h>

#include <miscfs/specfs/specdev.h>
#include <miscfs/fifofs/fifo.h>

#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/dir.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>

static int ufs_chmod __P((struct vnode *, int, struct ucred *, struct proc *));
static int ufs_chown
	__P((struct vnode *, uid_t, gid_t, struct ucred *, struct proc *));

union _qcvt {
	int64_t	qcvt;
	int32_t val[2];
};
#define SETHIGH(q, h) { \
	union _qcvt tmp; \
	tmp.qcvt = (q); \
	tmp.val[_QUAD_HIGHWORD] = (h); \
	(q) = tmp.qcvt; \
}
#define SETLOW(q, l) { \
	union _qcvt tmp; \
	tmp.qcvt = (q); \
	tmp.val[_QUAD_LOWWORD] = (l); \
	(q) = tmp.qcvt; \
}

/*
 * Create a regular file
 */
int
ufs_create(v)
	void *v;
{
	struct vop_create_args /* {
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
		struct vattr *a_vap;
	} */ *ap = v;
	return
	    ufs_makeinode(MAKEIMODE(ap->a_vap->va_type, ap->a_vap->va_mode),
			  ap->a_dvp, ap->a_vpp, ap->a_cnp);
}

/*
 * Mknod vnode call
 */
/* ARGSUSED */
int
ufs_mknod(v)
	void *v;
{
	struct vop_mknod_args /* {
		struct vnode *a_dvp;
		struct vnode **a_vpp;
		struct componentname *a_cnp;
		struct vattr *a_vap;
	} */ *ap = v;
	register struct vattr *vap = ap->a_vap;
	register struct vnode **vpp = ap->a_vpp;
	register struct inode *ip;
	int error;

	if ((error =
	    ufs_makeinode(MAKEIMODE(vap->va_type, vap->va_mode),
	    ap->a_dvp, vpp, ap->a_cnp)) != 0)
		return (error);
	ip = VTOI(*vpp);
	ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
	if (vap->va_rdev != VNOVAL) {
		/*
		 * Want to be able to use this to make badblock
		 * inodes, so don't truncate the dev number.
		 */
		ip->i_rdev = vap->va_rdev;
	}
	/*
	 * Remove inode so that it will be reloaded by VFS_VGET and
	 * checked to see if it is an alias of an existing entry in
	 * the inode cache.
	 */
	vput(*vpp);
	(*vpp)->v_type = VNON;
	vgone(*vpp);
	*vpp = 0;
	return (0);
}

/*
 * Open called.
 *
 * Nothing to do.
 */
/* ARGSUSED */
int
ufs_open(v)
	void *v;
{
	struct vop_open_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap = v;

	/*
	 * Files marked append-only must be opened for appending.
	 */
	if ((VTOI(ap->a_vp)->i_flags & APPEND) &&
	    (ap->a_mode & (FWRITE | O_APPEND)) == FWRITE)
		return (EPERM);
	return (0);
}

/*
 * Close called.
 *
 * Update the times on the inode.
 */
/* ARGSUSED */
int
ufs_close(v)
	void *v;
{
	struct vop_close_args /* {
		struct vnode *a_vp;
		int  a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap = v;
	register struct vnode *vp = ap->a_vp;
	register struct inode *ip = VTOI(vp);

	if (vp->v_usecount > 1 && !(ip->i_flag & IN_LOCKED))
		ITIMES(ip, &time, &time);
	return (0);
}

int
ufs_access(v)
	void *v;
{
	struct vop_access_args /* {
		struct vnode *a_vp;
		int  a_mode;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap = v;
	register struct vnode *vp = ap->a_vp;
	register struct inode *ip = VTOI(vp);
	mode_t mode = ap->a_mode;

#ifdef DIAGNOSTIC
	if (!VOP_ISLOCKED(vp)) {
		vprint("ufs_access: not locked", vp);
		panic("ufs_access: not locked");
	}
#endif
#ifdef QUOTA
	if (mode & VWRITE)
		switch (vp->v_type) {
			int error;
		case VDIR:
		case VLNK:
		case VREG:
			if ((error = getinoquota(ip)) != 0)
				return (error);
			break;
		case VBAD:
		case VBLK:
		case VCHR:
		case VSOCK:
		case VFIFO:
		case VNON:
			break;
		}
#endif

	/* If immutable bit set, nobody gets to write it. */
	if ((mode & VWRITE) && (ip->i_flags & IMMUTABLE))
		return (EPERM);

	return (vaccess(ip->i_mode, ip->i_uid, ip->i_gid, mode, ap->a_cred));
}

/* ARGSUSED */
int
ufs_getattr(v)
	void *v;
{
	struct vop_getattr_args /* {
		struct vnode *a_vp;
		struct vattr *a_vap;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap = v;
	register struct vnode *vp = ap->a_vp;
	register struct inode *ip = VTOI(vp);
	register struct vattr *vap = ap->a_vap;

	ITIMES(ip, &time, &time);
	/*
	 * Copy from inode table
	 */
	vap->va_fsid = ip->i_dev;
	vap->va_fileid = ip->i_number;
	vap->va_mode = ip->i_mode & ~IFMT;
	vap->va_nlink = ip->i_nlink;
	vap->va_uid = ip->i_uid;
	vap->va_gid = ip->i_gid;
	vap->va_rdev = (dev_t)ip->i_rdev;
	vap->va_size = ip->i_din.di_size;
	vap->va_atime.tv_sec = ip->i_atime;
	vap->va_atime.tv_nsec = ip->i_atimensec;
	vap->va_mtime.tv_sec = ip->i_mtime;
	vap->va_mtime.tv_nsec = ip->i_mtimensec;
	vap->va_ctime.tv_sec = ip->i_ctime;
	vap->va_ctime.tv_nsec = ip->i_ctimensec;
	vap->va_flags = ip->i_flags;
	vap->va_gen = ip->i_gen;
	/* this doesn't belong here */
	if (vp->v_type == VBLK)
		vap->va_blocksize = BLKDEV_IOSIZE;
	else if (vp->v_type == VCHR)
		vap->va_blocksize = MAXBSIZE;
	else
		vap->va_blocksize = vp->v_mount->mnt_stat.f_iosize;
	vap->va_bytes = dbtob(ip->i_blocks);
	vap->va_type = vp->v_type;
	vap->va_filerev = ip->i_modrev;
	return (0);
}

/*
 * Set attribute vnode op. called from several syscalls
 */
int
ufs_setattr(v)
	void *v;
{
	struct vop_setattr_args /* {
		struct vnode *a_vp;
		struct vattr *a_vap;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap = v;
	register struct vattr *vap = ap->a_vap;
	register struct vnode *vp = ap->a_vp;
	register struct inode *ip = VTOI(vp);
	register struct ucred *cred = ap->a_cred;
	register struct proc *p = ap->a_p;
	int error;

	/*
	 * Check for unsettable attributes.
	 */
	if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
	    (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
	    (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
	    ((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
		return (EINVAL);
	}
	if (vap->va_flags != VNOVAL) {
		if (cred->cr_uid != ip->i_uid &&
		    (error = suser(cred, &p->p_acflag)))
			return (error);
		if (cred->cr_uid == 0) {
			if ((ip->i_flags & (SF_IMMUTABLE | SF_APPEND)) &&
			    securelevel > 0)
				return (EPERM);
			ip->i_flags = vap->va_flags;
		} else {
			if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND))
				return (EPERM);
			ip->i_flags &= SF_SETTABLE;
			ip->i_flags |= (vap->va_flags & UF_SETTABLE);
		}
		ip->i_flag |= IN_CHANGE;
		if (vap->va_flags & (IMMUTABLE | APPEND))
			return (0);
	}
	if (ip->i_flags & (IMMUTABLE | APPEND))
		return (EPERM);
	/*
	 * Go through the fields and update iff not VNOVAL.
	 */
	if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
		error = ufs_chown(vp, vap->va_uid, vap->va_gid, cred, p);
		if (error)
			return (error);
	}
	if (vap->va_size != VNOVAL) {
		if (vp->v_type == VDIR)
			return (EISDIR);
		error = VOP_TRUNCATE(vp, vap->va_size, 0, cred, p);
		if (error)
			return (error);
	}
	ip = VTOI(vp);
	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
		if (cred->cr_uid != ip->i_uid &&
		    (error = suser(cred, &p->p_acflag)) &&
		    ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || 
		    (error = VOP_ACCESS(vp, VWRITE, cred, p))))
			return (error);
		if (vap->va_atime.tv_sec != VNOVAL)
			ip->i_flag |= IN_ACCESS;
		if (vap->va_mtime.tv_sec != VNOVAL)
			ip->i_flag |= IN_CHANGE | IN_UPDATE;
		error = VOP_UPDATE(vp, &vap->va_atime, &vap->va_mtime, 1);
		if (error)
			return (error);
	}
	error = 0;
	if (vap->va_mode != (mode_t)VNOVAL)
		error = ufs_chmod(vp, (int)vap->va_mode, cred, p);
	return (error);
}

/*
 * Change the mode on a file.
 * Inode must be locked before calling.
 */
static int
ufs_chmod(vp, mode, cred, p)
	register struct vnode *vp;
	register int mode;
	register struct ucred *cred;
	struct proc *p;
{
	register struct inode *ip = VTOI(vp);
	int error;

	if (cred->cr_uid != ip->i_uid &&
	    (error = suser(cred, &p->p_acflag)))
		return (error);
	if (cred->cr_uid) {
		if (vp->v_type != VDIR && (mode & S_ISTXT))
			return (EFTYPE);
		if (!groupmember(ip->i_gid, cred) && (mode & ISGID))
			return (EPERM);
	}
	ip->i_mode &= ~ALLPERMS;
	ip->i_mode |= (mode & ALLPERMS);
	ip->i_flag |= IN_CHANGE;
	if ((vp->v_flag & VTEXT) && (ip->i_mode & S_ISTXT) == 0)
		(void) vnode_pager_uncache(vp);
	return (0);
}

/*
 * Perform chown operation on inode ip;
 * inode must be locked prior to call.
 */
static int
ufs_chown(vp, uid, gid, cred, p)
	register struct vnode *vp;
	uid_t uid;
	gid_t gid;
	struct ucred *cred;
	struct proc *p;
{
	register struct inode *ip = VTOI(vp);
	uid_t ouid;
	gid_t ogid;
	int error = 0;
#ifdef QUOTA
	register int i;
	long change;
#endif

	if (uid == (uid_t)VNOVAL)
		uid = ip->i_uid;
	if (gid == (gid_t)VNOVAL)
		gid = ip->i_gid;
	/*
	 * If we don't own the file, are trying to change the owner
	 * of the file, or are not a member of the target group,
	 * the caller must be superuser or the call fails.
	 */
	if ((cred->cr_uid != ip->i_uid || uid != ip->i_uid ||
	    (gid != ip->i_gid && !groupmember((gid_t)gid, cred))) &&
	    (error = suser(cred, &p->p_acflag)))
		return (error);
	ogid = ip->i_gid;
	ouid = ip->i_uid;
#ifdef QUOTA
	if ((error = getinoquota(ip)) != 0)
		return (error);
	if (ouid == uid) {
		dqrele(vp, ip->i_dquot[USRQUOTA]);
		ip->i_dquot[USRQUOTA] = NODQUOT;
	}
	if (ogid == gid) {
		dqrele(vp, ip->i_dquot[GRPQUOTA]);
		ip->i_dquot[GRPQUOTA] = NODQUOT;
	}
	change = ip->i_blocks;
	(void) chkdq(ip, -change, cred, CHOWN);
	(void) chkiq(ip, -1, cred, CHOWN);
	for (i = 0; i < MAXQUOTAS; i++) {
		dqrele(vp, ip->i_dquot[i]);
		ip->i_dquot[i] = NODQUOT;
	}
#endif
	ip->i_gid = gid;
	ip->i_uid = uid;
#ifdef QUOTA
	if ((error = getinoquota(ip)) == 0) {
		if (ouid == uid) {
			dqrele(vp, ip->i_dquot[USRQUOTA]);
			ip->i_dquot[USRQUOTA] = NODQUOT;
		}
		if (ogid == gid) {
			dqrele(vp, ip->i_dquot[GRPQUOTA]);
			ip->i_dquot[GRPQUOTA] = NODQUOT;
		}
		if ((error = chkdq(ip, change, cred, CHOWN)) == 0) {
			if ((error = chkiq(ip, 1, cred, CHOWN)) == 0)
				goto good;
			else
				(void) chkdq(ip, -change, cred, CHOWN|FORCE);
		}
		for (i = 0; i < MAXQUOTAS; i++) {
			dqrele(vp, ip->i_dquot[i]);
			ip->i_dquot[i] = NODQUOT;
		}
	}
	ip->i_gid = ogid;
	ip->i_uid = ouid;
	if (getinoquota(ip) == 0) {
		if (ouid == uid) {
			dqrele(vp, ip->i_dquot[USRQUOTA]);
			ip->i_dquot[USRQUOTA] = NODQUOT;
		}
		if (ogid == gid) {
			dqrele(vp, ip->i_dquot[GRPQUOTA]);
			ip->i_dquot[GRPQUOTA] = NODQUOT;
		}
		(void) chkdq(ip, change, cred, FORCE|CHOWN);
		(void) chkiq(ip, 1, cred, FORCE|CHOWN);
		(void) getinoquota(ip);
	}
	return (error);
good:
	if (getinoquota(ip))
		panic("chown: lost quota");
#endif /* QUOTA */
	if (ouid != uid || ogid != gid)
		ip->i_flag |= IN_CHANGE;
	if (ouid != uid && cred->cr_uid != 0)
		ip->i_mode &= ~ISUID;
	if (ogid != gid && cred->cr_uid != 0)