/*
* fs/cifs/cifsacl.c
*
* Copyright (C) International Business Machines Corp., 2007,2008
* Author(s): Steve French (sfrench@us.ibm.com)
*
* Contains the routines for mapping CIFS/NTFS ACLs
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/keyctl.h>
#include <linux/key-type.h>
#include <keys/user-type.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsacl.h"
#include "cifsproto.h"
#include "cifs_debug.h"
/* security id for everyone/world system group */
static const struct cifs_sid sid_everyone = {
1, 1, {0, 0, 0, 0, 0, 1}, {0} };
/* security id for Authenticated Users system group */
static const struct cifs_sid sid_authusers = {
1, 1, {0, 0, 0, 0, 0, 5}, {__constant_cpu_to_le32(11)} };
/* group users */
static const struct cifs_sid sid_user = {1, 2 , {0, 0, 0, 0, 0, 5}, {} };
static const struct cred *root_cred;
static int
cifs_idmap_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
{
char *payload;
/*
* If the payload is less than or equal to the size of a pointer, then
* an allocation here is wasteful. Just copy the data directly to the
* payload.value union member instead.
*
* With this however, you must check the datalen before trying to
* dereference payload.data!
*/
if (prep->datalen <= sizeof(key->payload)) {
key->payload.value = 0;
memcpy(&key->payload.value, prep->data, prep->datalen);
key->datalen = prep->datalen;
return 0;
}
payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL);
if (!payload)
return -ENOMEM;
key->payload.data = payload;
key->datalen = prep->datalen;
return 0;
}
static inline void
cifs_idmap_key_destroy(struct key *key)
{
if (key->datalen > sizeof(key->payload))
kfree(key->payload.data);
}
static struct key_type cifs_idmap_key_type = {
.name = "cifs.idmap",
.instantiate = cifs_idmap_key_instantiate,
.destroy = cifs_idmap_key_destroy,
.describe = user_describe,
};
static char *
sid_to_key_str(struct cifs_sid *sidptr, unsigned int type)
{
int i, len;
unsigned int saval;
char *sidstr, *strptr;
unsigned long long id_auth_val;
/* 3 bytes for prefix */
sidstr = kmalloc(3 + SID_STRING_BASE_SIZE +
(SID_STRING_SUBAUTH_SIZE * sidptr->num_subauth),
GFP_KERNEL);
if (!sidstr)
return sidstr;
strptr = sidstr;
len = sprintf(strptr, "%cs:S-%hhu", type == SIDOWNER ? 'o' : 'g',
sidptr->revision);
strptr += len;
/* The authority field is a single 48-bit number */
id_auth_val = (unsigned long long)sidptr->authority[5];
id_auth_val |= (unsigned long long)sidptr->authority[4] << 8;
id_auth_val |= (unsigned long long)sidptr->authority[