1 /* $OpenBSD: x509_trs.c,v 1.55 2024/03/26 22:43:42 tb Exp $ */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project 1999.
4 */
5 /* ====================================================================
6 * Copyright (c) 1999 The OpenSSL Project. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * licensing@OpenSSL.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 * acknowledgment:
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59 #include <stdio.h>
60
61 #include <openssl/asn1.h>
62 #include <openssl/objects.h>
63 #include <openssl/x509.h>
64 #include <openssl/x509v3.h>
65
66 #include "x509_internal.h"
67 #include "x509_local.h"
68
69 static int
obj_trust(int id,const X509 * x)70 obj_trust(int id, const X509 *x)
71 {
72 const X509_CERT_AUX *aux;
73 ASN1_OBJECT *obj;
74 int i, nid;
75
76 if ((aux = x->aux) == NULL)
77 return X509_TRUST_UNTRUSTED;
78
79 for (i = 0; i < sk_ASN1_OBJECT_num(aux->reject); i++) {
80 obj = sk_ASN1_OBJECT_value(aux->reject, i);
81 nid = OBJ_obj2nid(obj);
82 if (nid == id || nid == NID_anyExtendedKeyUsage)
83 return X509_TRUST_REJECTED;
84 }
85
86 for (i = 0; i < sk_ASN1_OBJECT_num(aux->trust); i++) {
87 obj = sk_ASN1_OBJECT_value(aux->trust, i);
88 nid = OBJ_obj2nid(obj);
89 if (nid == id || nid == NID_anyExtendedKeyUsage)
90 return X509_TRUST_TRUSTED;
91 }
92
93 return X509_TRUST_UNTRUSTED;
94 }
95
96 static int
trust_compat(int nid,const X509 * x)97 trust_compat(int nid, const X509 *x)
98 {
99 /* Extensions already cached in X509_check_trust(). */
100 if ((x->ex_flags & EXFLAG_SS) != 0)
101 return X509_TRUST_TRUSTED;
102
103 return X509_TRUST_UNTRUSTED;
104 }
105
106 static int
trust_1oidany(int nid,const X509 * x)107 trust_1oidany(int nid, const X509 *x)
108 {
109 /* Inspect the certificate's trust settings if there are any. */
110 if (x->aux != NULL && (x->aux->trust != NULL || x->aux->reject != NULL))
111 return obj_trust(nid, x);
112
113 /* For compatibility we return trusted if the cert is self signed. */
114 return trust_compat(NID_undef, x);
115 }
116
117 static int
trust_1oid(int nid,const X509 * x)118 trust_1oid(int nid, const X509 *x)
119 {
120 if (x->aux != NULL)
121 return obj_trust(nid, x);
122
123 return X509_TRUST_UNTRUSTED;
124 }
125
126 int
X509_check_trust(X509 * x,int trust_id,int flags)127 X509_check_trust(X509 *x, int trust_id, int flags)
128 {
129 int rv;
130
131 if (trust_id == -1)
132 return 1;
133
134 /* Call early so the trust handlers don't need to modify the certs. */
135 if (!x509v3_cache_extensions(x))
136 return X509_TRUST_UNTRUSTED;
137
138 switch (trust_id) {
139 case 0:
140 /*
141 * XXX beck/jsing This enables self signed certs to be trusted
142 * for an unspecified id/trust flag value (this is NOT the
143 * X509_TRUST_DEFAULT), which was the longstanding openssl
144 * behaviour. boringssl does not have this behaviour.
145 *
146 * This should be revisited, but changing the default
147 * "not default" may break things.
148 */
149 rv = obj_trust(NID_anyExtendedKeyUsage, x);
150 if (rv != X509_TRUST_UNTRUSTED)
151 return rv;
152 return trust_compat(NID_undef, x);
153 case X509_TRUST_COMPAT:
154 return trust_compat(NID_undef, x);
155 case X509_TRUST_SSL_CLIENT:
156 return trust_1oidany(NID_client_auth, x);
157 case X509_TRUST_SSL_SERVER:
158 return trust_1oidany(NID_server_auth, x);
159 case X509_TRUST_EMAIL:
160 return trust_1oidany(NID_email_protect, x);
161 case X509_TRUST_OBJECT_SIGN:
162 return trust_1oidany(NID_code_sign, x);
163 case X509_TRUST_OCSP_SIGN:
164 return trust_1oid(NID_OCSP_sign, x);
165 case X509_TRUST_OCSP_REQUEST:
166 return trust_1oid(NID_ad_OCSP, x);
167 case X509_TRUST_TSA:
168 return trust_1oidany(NID_time_stamp, x);
169 default:
170 return obj_trust(trust_id, x);
171 }
172 }
173 LCRYPTO_ALIAS(X509_check_trust);
174