blob: 87e8ff67ae1158e5bf7040a92579c8a4c40fa86c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
// SPDX-License-Identifier: GPL-2.0+
/*
* X509 helper functions
*
* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/err.h>
#include <crypto/public_key.h>
#include <crypto/x509_parser.h>
/*
* Check for self-signedness in an X.509 cert and if found, check the signature
* immediately if we can.
*/
int x509_check_for_self_signed(struct x509_certificate *cert)
{
int ret = 0;
if (cert->raw_subject_size != cert->raw_issuer_size ||
memcmp(cert->raw_subject, cert->raw_issuer,
cert->raw_issuer_size))
goto not_self_signed;
if (cert->sig->auth_ids[0] || cert->sig->auth_ids[1]) {
/*
* If the AKID is present it may have one or two parts. If
* both are supplied, both must match.
*/
bool a = asymmetric_key_id_same(cert->skid,
cert->sig->auth_ids[1]);
bool b = asymmetric_key_id_same(cert->id,
cert->sig->auth_ids[0]);
if (!a && !b)
goto not_self_signed;
ret = -EKEYREJECTED;
if (((a && !b) || (b && !a)) &&
cert->sig->auth_ids[0] && cert->sig->auth_ids[1])
goto out;
}
ret = -EKEYREJECTED;
if (strcmp(cert->pub->pkey_algo, cert->sig->pkey_algo))
goto out;
ret = public_key_verify_signature(cert->pub, cert->sig);
if (ret == -ENOPKG) {
cert->unsupported_sig = true;
goto not_self_signed;
}
if (ret < 0)
goto out;
pr_devel("Cert Self-signature verified");
cert->self_signed = true;
out:
return ret;
not_self_signed:
return 0;
}
|
