1/*
2 * Copyright (C) 2010 IBM Corporation
3 * Copyright (C) 2010 Politecnico di Torino, Italy
4 *                    TORSEC group -- http://security.polito.it
5 *
6 * Authors:
7 * Mimi Zohar <zohar@us.ibm.com>
8 * Roberto Sassu <roberto.sassu@polito.it>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation, version 2 of the License.
13 *
14 * See Documentation/security/keys-trusted-encrypted.txt
15 */
16
17#include <linux/uaccess.h>
18#include <linux/module.h>
19#include <linux/err.h>
20#include <keys/trusted-type.h>
21#include <keys/encrypted-type.h>
22#include "encrypted.h"
23
24/*
25 * request_trusted_key - request the trusted key
26 *
27 * Trusted keys are sealed to PCRs and other metadata. Although userspace
28 * manages both trusted/encrypted key-types, like the encrypted key type
29 * data, trusted key type data is not visible decrypted from userspace.
30 */
31struct key *request_trusted_key(const char *trusted_desc,
32				u8 **master_key, size_t *master_keylen)
33{
34	struct trusted_key_payload *tpayload;
35	struct key *tkey;
36
37	tkey = request_key(&key_type_trusted, trusted_desc, NULL);
38	if (IS_ERR(tkey))
39		goto error;
40
41	down_read(&tkey->sem);
42	tpayload = tkey->payload.data;
43	*master_key = tpayload->key;
44	*master_keylen = tpayload->key_len;
45error:
46	return tkey;
47}
48