Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* Signature verification with an asymmetric key
3 *
4 * See Documentation/crypto/asymmetric-keys.txt
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 aymmetric 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 * encrypt_blob - Encrypt data using an asymmetric key
69 * @params: Various parameters
70 * @data: Data blob to be encrypted, length params->data_len
71 * @enc: Encrypted data buffer, length params->enc_len
72 *
73 * Encrypt the specified data blob using the private key specified by
74 * params->key. The encrypted data is wrapped in an encoding if
75 * params->encoding is specified (eg. "pkcs1").
76 *
77 * Returns the length of the data placed in the encrypted data buffer or an
78 * error.
79 */
80int encrypt_blob(struct kernel_pkey_params *params,
81 const void *data, void *enc)
82{
83 params->op = kernel_pkey_encrypt;
84 return asymmetric_key_eds_op(params, data, enc);
85}
86EXPORT_SYMBOL_GPL(encrypt_blob);
87
88/**
89 * decrypt_blob - Decrypt data using an asymmetric key
90 * @params: Various parameters
91 * @enc: Encrypted data to be decrypted, length params->enc_len
92 * @data: Decrypted data buffer, length params->data_len
93 *
94 * Decrypt the specified data blob using the private key specified by
95 * params->key. The decrypted data is wrapped in an encoding if
96 * params->encoding is specified (eg. "pkcs1").
97 *
98 * Returns the length of the data placed in the decrypted data buffer or an
99 * error.
100 */
101int decrypt_blob(struct kernel_pkey_params *params,
102 const void *enc, void *data)
103{
104 params->op = kernel_pkey_decrypt;
105 return asymmetric_key_eds_op(params, enc, data);
106}
107EXPORT_SYMBOL_GPL(decrypt_blob);
108
109/**
110 * create_signature - Sign some data using an asymmetric key
111 * @params: Various parameters
112 * @data: Data blob to be signed, length params->data_len
113 * @enc: Signature buffer, length params->enc_len
114 *
115 * Sign the specified data blob using the private key specified by params->key.
116 * The signature is wrapped in an encoding if params->encoding is specified
117 * (eg. "pkcs1"). If the encoding needs to know the digest type, this can be
118 * passed through params->hash_algo (eg. "sha1").
119 *
120 * Returns the length of the data placed in the signature buffer or an error.
121 */
122int create_signature(struct kernel_pkey_params *params,
123 const void *data, void *enc)
124{
125 params->op = kernel_pkey_sign;
126 return asymmetric_key_eds_op(params, data, enc);
127}
128EXPORT_SYMBOL_GPL(create_signature);
129
130/**
131 * verify_signature - Initiate the use of an asymmetric key to verify a signature
132 * @key: The asymmetric key to verify against
133 * @sig: The signature to check
134 *
135 * Returns 0 if successful or else an error.
136 */
137int verify_signature(const struct key *key,
138 const struct public_key_signature *sig)
139{
140 const struct asymmetric_key_subtype *subtype;
141 int ret;
142
143 pr_devel("==>%s()\n", __func__);
144
145 if (key->type != &key_type_asymmetric)
146 return -EINVAL;
147 subtype = asymmetric_key_subtype(key);
148 if (!subtype ||
149 !key->payload.data[0])
150 return -EINVAL;
151 if (!subtype->verify_signature)
152 return -ENOTSUPP;
153
154 ret = subtype->verify_signature(key, sig);
155
156 pr_devel("<==%s() = %d\n", __func__, ret);
157 return ret;
158}
159EXPORT_SYMBOL_GPL(verify_signature);
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#define pr_fmt(fmt) "SIG: "fmt
15#include <keys/asymmetric-subtype.h>
16#include <linux/export.h>
17#include <linux/err.h>
18#include <linux/slab.h>
19#include <crypto/public_key.h>
20#include "asymmetric_keys.h"
21
22/*
23 * Destroy a public key signature.
24 */
25void public_key_signature_free(struct public_key_signature *sig)
26{
27 int i;
28
29 if (sig) {
30 for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++)
31 kfree(sig->auth_ids[i]);
32 kfree(sig->s);
33 kfree(sig->digest);
34 kfree(sig);
35 }
36}
37EXPORT_SYMBOL_GPL(public_key_signature_free);
38
39/**
40 * verify_signature - Initiate the use of an asymmetric key to verify a signature
41 * @key: The asymmetric key to verify against
42 * @sig: The signature to check
43 *
44 * Returns 0 if successful or else an error.
45 */
46int verify_signature(const struct key *key,
47 const struct public_key_signature *sig)
48{
49 const struct asymmetric_key_subtype *subtype;
50 int ret;
51
52 pr_devel("==>%s()\n", __func__);
53
54 if (key->type != &key_type_asymmetric)
55 return -EINVAL;
56 subtype = asymmetric_key_subtype(key);
57 if (!subtype ||
58 !key->payload.data[0])
59 return -EINVAL;
60 if (!subtype->verify_signature)
61 return -ENOTSUPP;
62
63 ret = subtype->verify_signature(key, sig);
64
65 pr_devel("<==%s() = %d\n", __func__, ret);
66 return ret;
67}
68EXPORT_SYMBOL_GPL(verify_signature);