1/* Signature verification with an asymmetric key
 2 *
 3 * See Documentation/security/asymmetric-keys.txt
 4 *
 5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
 6 * Written by David Howells (dhowells@redhat.com)
 7 *
 8 * This program is free software; you can redistribute it and/or
 9 * modify it under the terms of the GNU General Public Licence
10 * as published by the Free Software Foundation; either version
11 * 2 of the Licence, or (at your option) any later version.
12 */
13
 
14#include <keys/asymmetric-subtype.h>
15#include <linux/module.h>
16#include <linux/err.h>
 
 
17#include <crypto/public_key.h>
 
18#include "asymmetric_keys.h"
19
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
20/**
21 * verify_signature - Initiate the use of an asymmetric key to verify a signature
22 * @key: The asymmetric key to verify against
23 * @sig: The signature to check
24 *
25 * Returns 0 if successful or else an error.
26 */
27int verify_signature(const struct key *key,
28		     const struct public_key_signature *sig)
29{
30	const struct asymmetric_key_subtype *subtype;
31	int ret;
32
33	pr_devel("==>%s()\n", __func__);
34
35	if (key->type != &key_type_asymmetric)
36		return -EINVAL;
37	subtype = asymmetric_key_subtype(key);
38	if (!subtype ||
39	    !key->payload.data)
40		return -EINVAL;
41	if (!subtype->verify_signature)
42		return -ENOTSUPP;
43
44	ret = subtype->verify_signature(key, sig);
45
46	pr_devel("<==%s() = %d\n", __func__, ret);
47	return ret;
48}
49EXPORT_SYMBOL_GPL(verify_signature);

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/* Signature verification with an asymmetric key
 3 *
 4 * See Documentation/crypto/asymmetric-keys.rst
 5 *
 6 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
 7 * Written by David Howells (dhowells@redhat.com)
 
 
 
 
 
 8 */
 9
10#define pr_fmt(fmt) "SIG: "fmt
11#include <keys/asymmetric-subtype.h>
12#include <linux/export.h>
13#include <linux/err.h>
14#include <linux/slab.h>
15#include <linux/keyctl.h>
16#include <crypto/public_key.h>
17#include <keys/user-type.h>
18#include "asymmetric_keys.h"
19
20/*
21 * Destroy a public key signature.
22 */
23void public_key_signature_free(struct public_key_signature *sig)
24{
25	int i;
26
27	if (sig) {
28		for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++)
29			kfree(sig->auth_ids[i]);
30		kfree(sig->s);
31		kfree(sig->digest);
32		kfree(sig);
33	}
34}
35EXPORT_SYMBOL_GPL(public_key_signature_free);
36
37/**
38 * query_asymmetric_key - Get information about an asymmetric key.
39 * @params: Various parameters.
40 * @info: Where to put the information.
41 */
42int query_asymmetric_key(const struct kernel_pkey_params *params,
43			 struct kernel_pkey_query *info)
44{
45	const struct asymmetric_key_subtype *subtype;
46	struct key *key = params->key;
47	int ret;
48
49	pr_devel("==>%s()\n", __func__);
50
51	if (key->type != &key_type_asymmetric)
52		return -EINVAL;
53	subtype = asymmetric_key_subtype(key);
54	if (!subtype ||
55	    !key->payload.data[0])
56		return -EINVAL;
57	if (!subtype->query)
58		return -ENOTSUPP;
59
60	ret = subtype->query(params, info);
61
62	pr_devel("<==%s() = %d\n", __func__, ret);
63	return ret;
64}
65EXPORT_SYMBOL_GPL(query_asymmetric_key);
66
67/**
68 * verify_signature - Initiate the use of an asymmetric key to verify a signature
69 * @key: The asymmetric key to verify against
70 * @sig: The signature to check
71 *
72 * Returns 0 if successful or else an error.
73 */
74int verify_signature(const struct key *key,
75		     const struct public_key_signature *sig)
76{
77	const struct asymmetric_key_subtype *subtype;
78	int ret;
79
80	pr_devel("==>%s()\n", __func__);
81
82	if (key->type != &key_type_asymmetric)
83		return -EINVAL;
84	subtype = asymmetric_key_subtype(key);
85	if (!subtype ||
86	    !key->payload.data[0])
87		return -EINVAL;
88	if (!subtype->verify_signature)
89		return -ENOTSUPP;
90
91	ret = subtype->verify_signature(key, sig);
92
93	pr_devel("<==%s() = %d\n", __func__, ret);
94	return ret;
95}
96EXPORT_SYMBOL_GPL(verify_signature);