WSL2-Linux-Kernel/fs/jfs/acl.c

212 строки
4.6 KiB
C

/*
* Copyright (C) International Business Machines Corp., 2002-2004
* Copyright (C) Andreas Gruenbacher, 2001
* Copyright (C) Linus Torvalds, 1991, 1992
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/posix_acl_xattr.h>
#include "jfs_incore.h"
#include "jfs_txnmgr.h"
#include "jfs_xattr.h"
#include "jfs_acl.h"
static struct posix_acl *jfs_get_acl(struct inode *inode, int type)
{
struct posix_acl *acl;
char *ea_name;
int size;
char *value = NULL;
acl = get_cached_acl(inode, type);
if (acl != ACL_NOT_CACHED)
return acl;
switch(type) {
case ACL_TYPE_ACCESS:
ea_name = POSIX_ACL_XATTR_ACCESS;
break;
case ACL_TYPE_DEFAULT:
ea_name = POSIX_ACL_XATTR_DEFAULT;
break;
default:
return ERR_PTR(-EINVAL);
}
size = __jfs_getxattr(inode, ea_name, NULL, 0);
if (size > 0) {
value = kmalloc(size, GFP_KERNEL);
if (!value)
return ERR_PTR(-ENOMEM);
size = __jfs_getxattr(inode, ea_name, value, size);
}
if (size < 0) {
if (size == -ENODATA)
acl = NULL;
else
acl = ERR_PTR(size);
} else {
acl = posix_acl_from_xattr(value, size);
}
kfree(value);
if (!IS_ERR(acl))
set_cached_acl(inode, type, acl);
return acl;
}
static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
struct posix_acl *acl)
{
char *ea_name;
int rc;
int size = 0;
char *value = NULL;
if (S_ISLNK(inode->i_mode))
return -EOPNOTSUPP;
switch(type) {
case ACL_TYPE_ACCESS:
ea_name = POSIX_ACL_XATTR_ACCESS;
break;
case ACL_TYPE_DEFAULT:
ea_name = POSIX_ACL_XATTR_DEFAULT;
if (!S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
break;
default:
return -EINVAL;
}
if (acl) {
size = posix_acl_xattr_size(acl->a_count);
value = kmalloc(size, GFP_KERNEL);
if (!value)
return -ENOMEM;
rc = posix_acl_to_xattr(acl, value, size);
if (rc < 0)
goto out;
}
rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
out:
kfree(value);
if (!rc)
set_cached_acl(inode, type, acl);
return rc;
}
int jfs_check_acl(struct inode *inode, int mask, unsigned int flags)
{
struct posix_acl *acl;
if (flags & IPERM_FLAG_RCU)
return -ECHILD;
acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
int error = posix_acl_permission(inode, acl, mask);
posix_acl_release(acl);
return error;
}
return -EAGAIN;
}
int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
{
struct posix_acl *acl = NULL;
struct posix_acl *clone;
mode_t mode;
int rc = 0;
if (S_ISLNK(inode->i_mode))
return 0;
acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
if (S_ISDIR(inode->i_mode)) {
rc = jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, acl);
if (rc)
goto cleanup;
}
clone = posix_acl_clone(acl, GFP_KERNEL);
if (!clone) {
rc = -ENOMEM;
goto cleanup;
}
mode = inode->i_mode;
rc = posix_acl_create_masq(clone, &mode);
if (rc >= 0) {
inode->i_mode = mode;
if (rc > 0)
rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS,
clone);
}
posix_acl_release(clone);
cleanup:
posix_acl_release(acl);
} else
inode->i_mode &= ~current_umask();
JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
inode->i_mode;
return rc;
}
int jfs_acl_chmod(struct inode *inode)
{
struct posix_acl *acl, *clone;
int rc;
if (S_ISLNK(inode->i_mode))
return -EOPNOTSUPP;
acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl) || !acl)
return PTR_ERR(acl);
clone = posix_acl_clone(acl, GFP_KERNEL);
posix_acl_release(acl);
if (!clone)
return -ENOMEM;
rc = posix_acl_chmod_masq(clone, inode->i_mode);
if (!rc) {
tid_t tid = txBegin(inode->i_sb, 0);
mutex_lock(&JFS_IP(inode)->commit_mutex);
rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, clone);
if (!rc)
rc = txCommit(tid, 1, &inode, 0);
txEnd(tid);
mutex_unlock(&JFS_IP(inode)->commit_mutex);
}
posix_acl_release(clone);
return rc;
}