/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* acl.c
*
* Copyright (C) 2004, 2008 Oracle. All rights reserved.
*
* CREDITS:
* Lots of code in this file is copy from linux/fs/ext3/acl.c.
* Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License version 2 as published by the Free Software Foundation.
*
* 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.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#define MLOG_MASK_PREFIX ML_INODE
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "alloc.h"
#include "dlmglue.h"
#include "file.h"
#include "ocfs2_fs.h"
#include "xattr.h"
#include "acl.h"
/*
* Convert from xattr value to acl struct.
*/
static struct posix_acl *ocfs2_acl_from_xattr(const void *value, size_t size)
{
int n, count;
struct posix_acl *acl;
if (!value)
return NULL;
if (size < sizeof(struct posix_acl_entry))
return ERR_PTR(-EINVAL);
count = size / sizeof(struct posix_acl_entry);
if (count < 0)
return ERR_PTR(-EINVAL);
if (count == 0)
return NULL;
acl = posix_acl_alloc(count, GFP_NOFS);
if (!acl)
return ERR_PTR(-ENOMEM);
for (n = 0; n < count; n++) {
struct ocfs2_acl_entry *entry =
(struct ocfs2_acl_entry *)value;
acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
acl->a_entries[n].e_id = le32_to_cpu(entry->e_id);
value += sizeof(struct posix_acl_entry);
}
return acl;
}
/*
* Convert acl struct to xattr value.
*/
static void *ocfs2_acl_to_xattr(const struct posix_acl *acl, size_t *size)
{
struct ocfs2_acl_entry *entry = NULL;
char *ocfs2_acl;
size_t n;
*size = acl->a_count * sizeof(struct posix_acl_entry);
ocfs2_acl = kmalloc(*size, GFP_NOFS);
if (!ocfs2_acl)
return ERR_PTR(-ENOMEM);
entry = (struct ocfs2_acl_entry *)ocfs2_acl;
for (n = 0; n < acl->a_count; n++, entry++) {
entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
}
return ocfs2_acl;
}
static struct posix_acl *ocfs2_get_acl_nolock(struct inode *inode,
int type,
struct buffer_head *di_bh)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
int name_index;
char *value = NULL;
struct posix_acl *acl;
int retval;
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return NULL;
switch (type) {
case ACL_TYPE_ACCESS:
name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
break;
case ACL_TYPE_DEFAULT:
name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
break;
default:
return ERR_PTR(-EINVAL);
}
retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, "", NULL, 0);
if (retval > 0) {
value = kmalloc(retval, GFP_NOFS);
if (!value)
return ERR_PTR(-ENOMEM);
retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index,
"", value, retval);
}
if (retval > 0)
acl = ocfs2_acl_from_xattr(value, retval);
else if (retval == -ENODATA || retval == 0)
acl = NULL;
else
acl = ERR_PTR(retval);
kfree(value);
return acl;
}
/*
* Get posix acl.
*/
static struct posix_acl *ocfs2_get_acl(struct inode *inode, int type)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct buffer_head *di_bh = NULL;
struct posix_acl *acl;
int ret;
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return NULL;
ret = ocfs2_inode_lock(inode, &di_bh, 0);
if (ret < 0) {
mlog_errno(ret);
acl = ERR_PTR(ret);
return acl;
}
acl = ocfs2_get_acl_nolock(inode, type, di_bh);
ocfs2_inode_unlock(inode, 0);
brelse(di_bh);
return acl;
}
/*
* Set the access or default ACL of an inode.
*/
static int ocfs2_set_acl(handle_t *handle,
struct inode *inode,
struct buffer_head *di_bh,
int type,
struct posix_acl *acl,
struct ocfs2_alloc_context *meta_ac,
struct ocfs2_alloc_context *data_ac)
{
int name_index;
void *value = NULL;
size_t size = 0;
int ret;
if (S_ISLNK(inode->i_mode))
return -EOPNOTSUPP;
switch (type) {
case ACL_TYPE_ACCESS:
name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
if (acl) {
mode_t mode = inode->i_mode;
ret = posix_acl_equiv_mode(acl, &mode);
if (ret < 0)
return ret;
else {
inode->i_mode = mode;
if (ret == 0)
acl = NULL;
}
}
break;
case ACL_TYPE_DEFAULT:
name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
if (!S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
break;
default:
return -EINVAL;
}
if (acl) {
value = ocfs2_acl_to_xattr(acl, &size);
if (IS_ERR(value))
return (int)PTR_ERR(value);
}
if (handle)
ret = ocfs2_xattr_set_handle(handle, inode, di_bh, name_index,
"", value, size, 0,
meta_ac, data_ac);
else
ret = ocfs2_xattr_set(inode, name_index, "", value, size, 0);
kfree(value);
return ret;
}
int ocfs2_check_acl(struct inode *inode, int mask)
{
struct posix_acl *acl = ocfs2_get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
int ret = posix_acl_permission(inode, acl, mask);
posix_acl_release(acl);
return ret;
}
return -EAGAIN;
}
static size_t ocfs2_xattr_list_acl_access(struct inode *inode,
char *list,
size_t list_len,
const char *name,
size_t name_len)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return 0;
if (list && size <= list_len)
memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
return size;
}
static size_t ocfs2_xattr_list_acl_default(struct inode *inode,
char *list,
size_t list_len,
const char *name,
size_t name_len)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return 0;
if (list && size <= list_len)
memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
return size;
}
static int ocfs2_xattr_get_acl(struct inode *inode,
int type,
void *buffer,
size_t size)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct posix_acl *acl;
int ret;
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return -EOPNOTSUPP;
acl = ocfs2_get_acl(inode, type);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl == NULL)
return -ENODATA;
ret = posix_acl_to_xattr(acl, buffer, size);
posix_acl_release(acl);
return ret;
}
static int ocfs2_xattr_get_acl_access(struct inode *inode,
const char *name,
void *buffer,
size_t size)
{
if (strcmp(name, "") != 0)
return -EINVAL;
return ocfs2_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
}
static int ocfs2_xattr_get_acl_default(struct inode *inode,
const char *name,
void *buffer,
size_t size)
{
if (strcmp(name, "") != 0)
return -EINVAL;
return ocfs2_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
}
static int ocfs2_xattr_set_acl(struct inode *inode,
int type,
const void *value,
size_t size)
{
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct posix_acl *acl;
int ret = 0;
if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
return -EOPNOTSUPP;
if (!is_owner_or_cap(inode))
return -EPERM;
if (value) {
acl = posix_acl_from_xattr(value, size);
if (IS_ERR(acl))
return PTR_ERR(acl);
else if (acl) {
ret = posix_acl_valid(acl);
if (ret)
goto cleanup;
}
} else
acl = NULL;
ret = ocfs2_set_acl(NULL, inode, NULL, type, acl, NULL, NULL);
cleanup:
posix_acl_release(acl);
return ret;
}
static int ocfs2_xattr_set_acl_access(struct inode *inode,
const char *name,
const void *value,
size_t size,
int flags)
{
if (strcmp(name, "") != 0)
return -EINVAL;
return ocfs2_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
}
static int ocfs2_xattr_set_acl_default(struct inode *inode,
const char *name,
const void *value,
size_t size,
int flags)
{
if (strcmp(name, "") != 0)
return -EINVAL;
return ocfs2_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
}
struct xattr_handler ocfs2_xattr_acl_access_handler = {
.prefix = POSIX_ACL_XATTR_ACCESS,
.list = ocfs2_xattr_list_acl_access,
.get = ocfs2_xattr_get_acl_access,
.set = ocfs2_xattr_set_acl_access,
};
struct xattr_handler ocfs2_xattr_acl_default_handler = {
.prefix = POSIX_ACL_XATTR_DEFAULT,
.list = ocfs2_xattr_list_acl_default,
.get = ocfs2_xattr_get_acl_default,
.set = ocfs2_xattr_set_acl_default,
};
