patch-2.4.25 linux-2.4.25/fs/xfs/xfs_cap.c

• Lines: 207
• Date: 2004-02-18 05:36:32.000000000 -0800
• Orig file: linux-2.4.24/fs/xfs/xfs_cap.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.24/fs/xfs/xfs_cap.c linux-2.4.25/fs/xfs/xfs_cap.c
@@ -0,0 +1,206 @@
+/*
+ * Copyright (c) 2002 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+
+STATIC int xfs_cap_allow_set(vnode_t *);
+
+
+/*
+ * Test for existence of capability attribute as efficiently as possible.
+ */
+int
+xfs_cap_vhascap(
+	vnode_t		*vp)
+{
+	int		error;
+	int		len = sizeof(xfs_cap_set_t);
+	int		flags = ATTR_KERNOVAL|ATTR_ROOT;
+
+	VOP_ATTR_GET(vp, SGI_CAP_LINUX, NULL, &len, flags, sys_cred, error);
+	return (error == 0);
+}
+
+/*
+ * Convert from extended attribute representation to in-memory for XFS.
+ */
+STATIC int
+posix_cap_xattr_to_xfs(
+	posix_cap_xattr		*src,
+	size_t			size,
+	xfs_cap_set_t		*dest)
+{
+	if (!src || !dest)
+		return EINVAL;
+
+	if (src->c_version != cpu_to_le32(POSIX_CAP_XATTR_VERSION))
+		return EINVAL;
+	if (src->c_abiversion != cpu_to_le32(_LINUX_CAPABILITY_VERSION))
+		return EINVAL;
+
+	if (size < sizeof(posix_cap_xattr))
+		return EINVAL;
+
+	ASSERT(sizeof(dest->cap_effective) == sizeof(src->c_effective));
+
+	dest->cap_effective	= src->c_effective;
+	dest->cap_permitted	= src->c_permitted;
+	dest->cap_inheritable	= src->c_inheritable;
+
+	return 0;
+}
+
+/*
+ * Convert from in-memory XFS to extended attribute representation.
+ */
+STATIC int
+posix_cap_xfs_to_xattr(
+	xfs_cap_set_t		*src,
+	posix_cap_xattr		*xattr_cap,
+	size_t			size)
+{
+	size_t			new_size = posix_cap_xattr_size();
+
+	if (size < new_size)
+		return -ERANGE;
+
+	ASSERT(sizeof(xattr_cap->c_effective) == sizeof(src->cap_effective));
+
+	xattr_cap->c_version	= cpu_to_le32(POSIX_CAP_XATTR_VERSION);
+	xattr_cap->c_abiversion	= cpu_to_le32(_LINUX_CAPABILITY_VERSION);
+	xattr_cap->c_effective	= src->cap_effective;
+	xattr_cap->c_permitted	= src->cap_permitted;
+	xattr_cap->c_inheritable= src->cap_inheritable;
+
+	return new_size;
+}
+
+int
+xfs_cap_vget(
+	vnode_t		*vp,
+	void		*cap,
+	size_t		size)
+{
+	int		error;
+	int		len = sizeof(xfs_cap_set_t);
+	int		flags = ATTR_ROOT;
+	xfs_cap_set_t	xfs_cap = { 0 };
+	posix_cap_xattr	*xattr_cap = cap;
+	char		*data = (char *)&xfs_cap;
+
+	VN_HOLD(vp);
+	if ((error = _MAC_VACCESS(vp, NULL, VREAD)))
+		goto out;
+
+	if (!size) {
+		flags |= ATTR_KERNOVAL;
+		data = NULL;
+	}
+	VOP_ATTR_GET(vp, SGI_CAP_LINUX, data, &len, flags, sys_cred, error);
+	if (error)
+		goto out;
+	ASSERT(len == sizeof(xfs_cap_set_t));
+
+	error = (size)? -posix_cap_xattr_size() :
+			-posix_cap_xfs_to_xattr(&xfs_cap, xattr_cap, size);
+out:
+	VN_RELE(vp);
+	return -error;
+}
+
+int
+xfs_cap_vremove(
+	vnode_t		*vp)
+{
+	int		error;
+
+	VN_HOLD(vp);
+	error = xfs_cap_allow_set(vp);
+	if (!error) {
+		VOP_ATTR_REMOVE(vp, SGI_CAP_LINUX, ATTR_ROOT, sys_cred, error);
+		if (error == ENOATTR)
+			error = 0;	/* 'scool */
+	}
+	VN_RELE(vp);
+	return -error;
+}
+
+int
+xfs_cap_vset(
+	vnode_t			*vp,
+	void			*cap,
+	size_t			size)
+{
+	posix_cap_xattr		*xattr_cap = cap;
+	xfs_cap_set_t		xfs_cap;
+	int			error;
+
+	if (!cap)
+		return -EINVAL;
+
+	error = posix_cap_xattr_to_xfs(xattr_cap, size, &xfs_cap);
+	if (error)
+		return -error;
+
+	VN_HOLD(vp);
+	error = xfs_cap_allow_set(vp);
+	if (error)
+		goto out;
+
+	VOP_ATTR_SET(vp, SGI_CAP_LINUX, (char *)&xfs_cap,
+			sizeof(xfs_cap_set_t), ATTR_ROOT, sys_cred, error);
+out:
+	VN_RELE(vp);
+	return -error;
+}
+
+STATIC int
+xfs_cap_allow_set(
+	vnode_t		*vp)
+{
+	vattr_t		va;
+	int		error;
+
+	if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
+		return EROFS;
+	if (vp->v_inode.i_flags & (S_IMMUTABLE|S_APPEND))
+		return EPERM;
+	if ((error = _MAC_VACCESS(vp, NULL, VWRITE)))
+		return error;
+	va.va_mask = XFS_AT_UID;
+	VOP_GETATTR(vp, &va, 0, NULL, error);
+	if (error)
+		return error;
+	if (va.va_uid != current->fsuid && !capable(CAP_FOWNER))
+		return EPERM;
+	return error;
+}