Exemple #1
0
static __be32
compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
		 const char *name, int namlen, u64 ino)
{
	struct svc_export	*exp;
	struct dentry		*dparent, *dchild;
	__be32 rv = nfserr_noent;

	dparent = cd->fh.fh_dentry;
	exp  = cd->fh.fh_export;

	if (isdotent(name, namlen)) {
		if (namlen == 2) {
			dchild = dget_parent(dparent);
			/* filesystem root - cannot return filehandle for ".." */
			if (dchild == dparent)
				goto out;
		} else
			dchild = dget(dparent);
	} else
		dchild = lookup_one_len_unlocked(name, dparent, namlen);
	if (IS_ERR(dchild))
		return rv;
	if (d_mountpoint(dchild))
		goto out;
	if (d_really_is_negative(dchild))
		goto out;
	if (dchild->d_inode->i_ino != ino)
		goto out;
	rv = fh_compose(fhp, exp, dchild, &cd->fh);
out:
	dput(dchild);
	return rv;
}
/*
 * Look up one component of a pathname.
 * N.B. After this call _both_ fhp and resfh need an fh_put
 *
 * If the lookup would cross a mountpoint, and the mounted filesystem
 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
 * accepted as it stands and the mounted directory is
 * returned. Otherwise the covered directory is returned.
 * NOTE: this mountpoint crossing is not supported properly by all
 *   clients and is explicitly disallowed for NFSv3
 *      NeilBrown <*****@*****.**>
 */
__be32
nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
				unsigned int len, struct svc_fh *resfh)
{
	struct svc_export	*exp;
	struct dentry		*dentry;
	__be32 err;

	err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
	if (err)
		return err;
	err = check_nfsd_access(exp, rqstp);
	if (err)
		goto out;
	/*
	 * Note: we compose the file handle now, but as the
	 * dentry may be negative, it may need to be updated.
	 */
	err = fh_compose(resfh, exp, dentry, fhp);
	if (!err && !dentry->d_inode)
		err = nfserr_noent;
out:
	dput(dentry);
	exp_put(exp);
	return err;
}
Exemple #3
0
static int
encode_entry(struct readdir_cd *cd, const char *name,
	     int namlen, off_t offset, ino_t ino, unsigned int d_type, int plus)
{
	u32		*p = cd->buffer;
	int		buflen, slen, elen;

	if (cd->offset)
		xdr_encode_hyper(cd->offset, (u64) offset);

	/* nfsd_readdir calls us with name == 0 when it wants us to
	 * set the last offset entry. */
	if (name == 0)
		return 0;

	/*
	dprintk("encode_entry(%.*s @%ld%s)\n",
		namlen, name, (long) offset, plus? " plus" : "");
	 */

	/* truncate filename if too long */
	if (namlen > NFS3_MAXNAMLEN)
		namlen = NFS3_MAXNAMLEN;

	slen = XDR_QUADLEN(namlen);
	elen = slen + NFS3_ENTRY_BAGGAGE
		+ (plus? NFS3_ENTRYPLUS_BAGGAGE : 0);
	if ((buflen = cd->buflen - elen) < 0) {
		cd->eob = 1;
		return -EINVAL;
	}
	*p++ = xdr_one;				 /* mark entry present */
	p    = xdr_encode_hyper(p, ino);	 /* file id */
	p    = xdr_encode_array(p, name, namlen);/* name length & name */

	cd->offset = p;			/* remember pointer */
	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);	/* offset of next entry */

	/* throw in readdirplus baggage */
	if (plus) {
		struct svc_fh	fh;
		struct svc_export	*exp;
		struct dentry		*dparent, *dchild;

		dparent = cd->dirfh->fh_dentry;
		exp  = cd->dirfh->fh_export;

		fh_init(&fh, NFS3_FHSIZE);
		if (isdotent(name, namlen)) {
			dchild = dparent;
			if (namlen == 2)
				dchild = dchild->d_parent;
			dchild = dget(dchild);
		} else
			dchild = lookup_one_len(name, dparent,namlen);
		if (IS_ERR(dchild))
			goto noexec;
		if (fh_compose(&fh, exp, dchild, cd->dirfh) != 0 || !dchild->d_inode)
			goto noexec;
		p = encode_post_op_attr(cd->rqstp, p, &fh);
		*p++ = xdr_one; /* yes, a file handle follows */
		p = encode_fh(p, &fh);
		fh_put(&fh);
	}

out:
	cd->buflen = buflen;
	cd->buffer = p;
	return 0;

noexec:
	*p++ = 0;
	*p++ = 0;
	goto out;
}
Exemple #4
0
/*
 * Look up one component of a pathname.
 * N.B. After this call _both_ fhp and resfh need an fh_put
 *
 * If the lookup would cross a mountpoint, and the mounted filesystem
 * is exported to the client with NFSEXP_CROSSMNT, then the lookup is
 * accepted as it stands and the mounted directory is
 * returned. Otherwise the covered directory is returned.
 * NOTE: this mountpoint crossing is not supported properly by all
 *   clients and is explicitly disallowed for NFSv3
 *      NeilBrown <*****@*****.**>
 */
int
nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
					int len, struct svc_fh *resfh)
{
	struct svc_export	*exp;
	struct dentry		*dparent;
	struct dentry		*dentry;
	int			err;

	dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);

	/* Obtain dentry and export. */
	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC);
	if (err)
		goto out;

	dparent = fhp->fh_dentry;
	exp  = fhp->fh_export;

	err = nfserr_acces;

	/* Lookup the name, but don't follow links */
	if (isdotent(name, len)) {
		if (len==1)
			dentry = dget(dparent);
		else  { /* must be ".." */
			/* checking mountpoint crossing is very different when stepping up */
			if (dparent == exp->ex_dentry) {
				if (!EX_CROSSMNT(exp))
					dentry = dget(dparent); /* .. == . just like at / */
				else
				{
					struct svc_export *exp2 = NULL;
					struct dentry *dp;
					struct vfsmount *mnt = mntget(exp->ex_mnt);
					dentry = dget(dparent);
					while(follow_up(&mnt, &dentry))
						;
					dp = dget(dentry->d_parent);
					dput(dentry);
					dentry = dp;
					for ( ; exp2 == NULL && dp->d_parent != dp;
					      dp=dp->d_parent)
						exp2 = exp_get(exp->ex_client, dp->d_inode->i_dev, dp->d_inode->i_ino);
					if (exp2==NULL) {
						dput(dentry);
						dentry = dget(dparent);
					} else {
						exp = exp2;
					}
					mntput(mnt);
				}
			} else
				dentry = dget(dparent->d_parent);
		}
	} else {
		fh_lock(fhp);
		dentry = lookup_one_len(name, dparent, len);
		err = PTR_ERR(dentry);
		if (IS_ERR(dentry))
			goto out_nfserr;
		/*
		 * check if we have crossed a mount point ...
		 */
		if (d_mountpoint(dentry)) {
			struct svc_export *exp2 = NULL;
			struct vfsmount *mnt = mntget(exp->ex_mnt);
			struct dentry *mounts = dget(dentry);
			while (follow_down(&mnt,&mounts)&&d_mountpoint(mounts))
				;
			exp2 = exp_get(rqstp->rq_client,
				       mounts->d_inode->i_dev,
				       mounts->d_inode->i_ino);
			if (exp2 && EX_CROSSMNT(exp2)) {
				/* successfully crossed mount point */
				exp = exp2;
				dput(dentry);
				dentry = mounts;
			} else
				dput(mounts);
			mntput(mnt);
		}
	}
	/*
	 * Note: we compose the file handle now, but as the
	 * dentry may be negative, it may need to be updated.
	 */
	err = fh_compose(resfh, exp, dentry, fhp);
	if (!err && !dentry->d_inode)
		err = nfserr_noent;
out:
	return err;

out_nfserr:
	err = nfserrno(err);
	goto out;
}
Exemple #5
0
/*
 * Look up one component of a pathname.
 * N.B. After this call _both_ fhp and resfh need an fh_put
 *
 * If the lookup would cross a mountpoint, and the mounted filesystem
 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
 * accepted as it stands and the mounted directory is
 * returned. Otherwise the covered directory is returned.
 * NOTE: this mountpoint crossing is not supported properly by all
 *   clients and is explicitly disallowed for NFSv3
 *      NeilBrown <*****@*****.**>
 */
int
nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
					int len, struct svc_fh *resfh)
{
	struct svc_export	*exp;
	struct dentry		*dparent;
	struct dentry		*dentry;
	int			err;

	dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);

	/* Obtain dentry and export. */
	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC);
	if (err)
		return err;

	dparent = fhp->fh_dentry;
	exp  = fhp->fh_export;
	exp_get(exp);

	err = nfserr_acces;

	/* Lookup the name, but don't follow links */
	if (isdotent(name, len)) {
		if (len==1)
			dentry = dget(dparent);
		else if (dparent != exp->ex_dentry) {
			dentry = dget_parent(dparent);
		} else  if (!EX_NOHIDE(exp))
			dentry = dget(dparent); /* .. == . just like at / */
		else {
			/* checking mountpoint crossing is very different when stepping up */
			struct svc_export *exp2 = NULL;
			struct dentry *dp;
			struct vfsmount *mnt = mntget(exp->ex_mnt);
			dentry = dget(dparent);
			while(dentry == mnt->mnt_root && follow_up(&mnt, &dentry))
				;
			dp = dget_parent(dentry);
			dput(dentry);
			dentry = dp;

			exp2 = exp_parent(exp->ex_client, mnt, dentry,
					  &rqstp->rq_chandle);
			if (IS_ERR(exp2)) {
				err = PTR_ERR(exp2);
				dput(dentry);
				mntput(mnt);
				goto out_nfserr;
			}
			if (!exp2) {
				dput(dentry);
				dentry = dget(dparent);
			} else {
				exp_put(exp);
				exp = exp2;
			}
			mntput(mnt);
		}
	} else {
		fh_lock(fhp);
		dentry = lookup_one_len(name, dparent, len);
		err = PTR_ERR(dentry);
		if (IS_ERR(dentry))
			goto out_nfserr;
		/*
		 * check if we have crossed a mount point ...
		 */
		if (d_mountpoint(dentry)) {
			if ((err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
				dput(dentry);
				goto out_nfserr;
			}
		}
	}
	/*
	 * Note: we compose the file handle now, but as the
	 * dentry may be negative, it may need to be updated.
	 */
	err = fh_compose(resfh, exp, dentry, fhp);
	if (!err && !dentry->d_inode)
		err = nfserr_noent;
	dput(dentry);
out:
	exp_put(exp);
	return err;

out_nfserr:
	err = nfserrno(err);
	goto out;
}
Exemple #6
0
/*
 * Create a symlink and look up its inode
 * N.B. After this call _both_ fhp and resfhp need an fh_put
 */
int
nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
				char *fname, int flen,
				char *path,  int plen,
				struct svc_fh *resfhp)
{
	struct dentry	*dentry, *dnew;
	struct inode	*dirp;
	int		err;

	err = nfserr_noent;
	if (!flen || !plen)
		goto out;

	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
	if (err)
		goto out;
	dentry = fhp->fh_dentry;

	err = nfserr_perm;
	if (nfsd_iscovered(dentry, fhp->fh_export))
		goto out;
	dirp = dentry->d_inode;
	if (!dirp->i_op	|| !dirp->i_op->symlink)
		goto out;

	dnew = lookup_dentry(fname, dget(dentry), 0);
	err = PTR_ERR(dnew);
	if (IS_ERR(dnew))
		goto out_nfserr;

	/*
	 * Lock the parent before checking for existence
	 */
	err = fh_lock_parent(fhp, dnew);
	if (err)
		goto out_compose;

	err = nfserr_exist;
	if (!dnew->d_inode) {
		DQUOT_INIT(dirp);
		err = dirp->i_op->symlink(dirp, dnew, path);
		DQUOT_DROP(dirp);
		if (!err) {
			if (EX_ISSYNC(fhp->fh_export))
				write_inode_now(dirp);
		} else
			err = nfserrno(-err);
	}
	fh_unlock(fhp);

	/* Compose the fh so the dentry will be freed ... */
out_compose:
	fh_compose(resfhp, fhp->fh_export, dnew);
out:
	return err;

out_nfserr:
	err = nfserrno(-err);
	goto out;
}
Exemple #7
0
/*
 * Create a file (regular, directory, device, fifo); UNIX sockets 
 * not yet implemented.
 * If the response fh has been verified, the parent directory should
 * already be locked. Note that the parent directory is left locked.
 *
 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
 */
int
nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
		char *fname, int flen, struct iattr *iap,
		int type, dev_t rdev, struct svc_fh *resfhp)
{
	struct dentry	*dentry, *dchild;
	struct inode	*dirp;
	nfsd_dirop_t	opfunc = NULL;
	int		err;

	err = nfserr_perm;
	if (!flen)
		goto out;
	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
	if (err)
		goto out;

	dentry = fhp->fh_dentry;
	dirp = dentry->d_inode;

	err = nfserr_notdir;
	if(!dirp->i_op || !dirp->i_op->lookup)
		goto out;
	/*
	 * Check whether the response file handle has been verified yet.
	 * If it has, the parent directory should already be locked.
	 */
	if (!resfhp->fh_dverified) {
		dchild = lookup_dentry(fname, dget(dentry), 0);
		err = PTR_ERR(dchild);
		if (IS_ERR(dchild))
			goto out_nfserr;
		fh_compose(resfhp, fhp->fh_export, dchild);
		/* Lock the parent and check for errors ... */
		err = fh_lock_parent(fhp, dchild);
		if (err)
			goto out;
	} else {
		dchild = resfhp->fh_dentry;
		if (!fhp->fh_locked)
			printk(KERN_ERR
				"nfsd_create: parent %s/%s not locked!\n",
				dentry->d_parent->d_name.name,
				dentry->d_name.name);
	}
	/*
	 * Make sure the child dentry is still negative ...
	 */
	err = nfserr_exist;
	if (dchild->d_inode) {
		printk(KERN_WARNING
			"nfsd_create: dentry %s/%s not negative!\n",
			dentry->d_name.name, dchild->d_name.name);
		goto out; 
	}

	/*
	 * Get the dir op function pointer.
	 */
	err = nfserr_perm;
	switch (type) {
	case S_IFREG:
		opfunc = (nfsd_dirop_t) dirp->i_op->create;
		break;
	case S_IFDIR:
		opfunc = (nfsd_dirop_t) dirp->i_op->mkdir;
		break;
	case S_IFCHR:
	case S_IFBLK:
		/* The client is _NOT_ required to do security enforcement */
		if(!capable(CAP_SYS_ADMIN))
		{
			err = -EPERM;
			goto out;
		}
	case S_IFIFO:
	case S_IFSOCK:
		opfunc = dirp->i_op->mknod;
		break;
	}
	if (!opfunc)
		goto out;

	if (!(iap->ia_valid & ATTR_MODE))
		iap->ia_mode = 0;

	/*
	 * Call the dir op function to create the object.
	 */
	DQUOT_INIT(dirp);
	err = opfunc(dirp, dchild, iap->ia_mode, rdev);
	DQUOT_DROP(dirp);
	if (err < 0)
		goto out_nfserr;

	if (EX_ISSYNC(fhp->fh_export))
		write_inode_now(dirp);

	/*
	 * Update the file handle to get the new inode info.
	 */
	fh_update(resfhp);

	/* Set file attributes. Mode has already been set and
	 * setting uid/gid works only for root. Irix appears to
	 * send along the gid when it tries to implement setgid
	 * directories via NFS.
	 */
	err = 0;
	if ((iap->ia_valid &= (ATTR_UID|ATTR_GID|ATTR_MODE)) != 0)
		err = nfsd_setattr(rqstp, resfhp, iap);
out:
	return err;

out_nfserr:
	err = nfserrno(-err);
	goto out;
}
Exemple #8
0
/*
 * Look up one component of a pathname.
 * N.B. After this call _both_ fhp and resfh need an fh_put
 */
int
nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
					int len, struct svc_fh *resfh)
{
	struct svc_export	*exp;
	struct dentry		*dparent, *dchild;
	int			err;

	dprintk("nfsd: nfsd_lookup(fh %p, %s)\n", SVCFH_DENTRY(fhp), name);

	/* Obtain dentry and export. */
	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC);
	if (err)
		goto out;

	dparent = fhp->fh_dentry;
	exp  = fhp->fh_export;

#if 0
	err = nfsd_permission(exp, dparent, MAY_EXEC);
	if (err)
		goto out;
#endif
	err = nfserr_noent;
	if (fs_off_limits(dparent->d_sb))
		goto out;
	err = nfserr_acces;
	if (nfsd_iscovered(dparent, exp))
		goto out;

	/* Lookup the name, but don't follow links */
	dchild = lookup_dentry(name, dget(dparent), 0);
	if (IS_ERR(dchild))
		goto out_nfserr;
	/*
	 * check if we have crossed a mount point ...
	 */
	if (dchild->d_sb != dparent->d_sb) {
		struct dentry *tdentry;
		tdentry = dchild->d_covers;
		if (tdentry == dchild)
			goto out_dput;
	        dput(dchild);
		dchild = dget(tdentry);
	        if (dchild->d_sb != dparent->d_sb) {
printk("nfsd_lookup: %s/%s crossed mount point!\n", dparent->d_name.name, dchild->d_name.name);
			goto out_dput;
		}
	}

	/*
	 * Note: we compose the file handle now, but as the
	 * dentry may be negative, it may need to be updated.
	 */
	fh_compose(resfh, exp, dchild);
	err = nfserr_noent;
	if (dchild->d_inode)
		err = 0;
out:
	return err;

out_nfserr:
	err = nfserrno(-PTR_ERR(dchild));
	goto out;
out_dput:
	dput(dchild);
	err = nfserr_acces;
	goto out;
}