1X509_GET_EXTENSION_FLAGS(3) OpenSSL X509_GET_EXTENSION_FLAGS(3)
2
6 X509_get0_subject_key_id, X509_get0_authority_key_id, X509_get_pathlen,
7 X509_get_extension_flags, X509_get_key_usage,
8 X509_get_extended_key_usage, X509_set_proxy_flag,
9 X509_set_proxy_pathlen, X509_get_proxy_pathlen - retrieve certificate
10 extension data
11
13 #include <openssl/x509v3.h>
14 long X509_get_pathlen(X509 *x);
16 uint32_t X509_get_extension_flags(X509 *x);
17 uint32_t X509_get_key_usage(X509 *x);
18 uint32_t X509_get_extended_key_usage(X509 *x);
19 const ASN1_OCTET_STRING *X509_get0_subject_key_id(X509 *x);
20 const ASN1_OCTET_STRING *X509_get0_authority_key_id(X509 *x);
21 void X509_set_proxy_flag(X509 *x);
22 void X509_set_proxy_pathlen(int l);
23 long X509_get_proxy_pathlen(X509 *x);
24
26 These functions retrieve information related to commonly used
27 certificate extensions.
28 X509_get_pathlen() retrieves the path length extension from a
30 certificate. This extension is used to limit the length of a cert
31 chain that may be issued from that CA.
32 X509_get_extension_flags() retrieves general information about a
34 certificate, it will return one or more of the following flags ored
35 together.
36 EXFLAG_V1
38 The certificate is an obsolete version 1 certificate.
39 EXFLAG_BCONS
41 The certificate contains a basic constraints extension.
42 EXFLAG_CA
44 The certificate contains basic constraints and asserts the CA flag.
45 EXFLAG_PROXY
47 The certificate is a valid proxy certificate.
48 EXFLAG_SI
50 The certificate is self issued (that is subject and issuer names
51 match).
52 EXFLAG_SS
54 The subject and issuer names match and extension values imply it is
55 self signed.
56 EXFLAG_FRESHEST
58 The freshest CRL extension is present in the certificate.
59 EXFLAG_CRITICAL
61 The certificate contains an unhandled critical extension.
62 EXFLAG_INVALID
64 Some certificate extension values are invalid or inconsistent. The
65 certificate should be rejected.
66 EXFLAG_KUSAGE
68 The certificate contains a key usage extension. The value can be
69 retrieved using X509_get_key_usage().
70 EXFLAG_XKUSAGE
72 The certificate contains an extended key usage extension. The value
73 can be retrieved using X509_get_extended_key_usage().
74 X509_get_key_usage() returns the value of the key usage extension. If
76 key usage is present will return zero or more of the flags:
77 KU_DIGITAL_SIGNATURE, KU_NON_REPUDIATION, KU_KEY_ENCIPHERMENT,
78 KU_DATA_ENCIPHERMENT, KU_KEY_AGREEMENT, KU_KEY_CERT_SIGN, KU_CRL_SIGN,
79 KU_ENCIPHER_ONLY or KU_DECIPHER_ONLY corresponding to individual key
80 usage bits. If key usage is absent then UINT32_MAX is returned.
81 X509_get_extended_key_usage() returns the value of the extended key
83 usage extension. If extended key usage is present it will return zero
84 or more of the flags: XKU_SSL_SERVER, XKU_SSL_CLIENT, XKU_SMIME,
85 XKU_CODE_SIGN XKU_OCSP_SIGN, XKU_TIMESTAMP, XKU_DVCS or XKU_ANYEKU.
86 These correspond to the OIDs id-kp-serverAuth, id-kp-clientAuth, id-kp-
87 emailProtection, id-kp-codeSigning, id-kp-OCSPSigning, id-kp-
88 timeStamping, id-kp-dvcs and anyExtendedKeyUsage respectively.
89 Additionally XKU_SGC is set if either Netscape or Microsoft SGC OIDs
90 are present.
91 X509_get0_subject_key_id() returns an internal pointer to the subject
93 key identifier of x as an ASN1_OCTET_STRING or NULL if the extension is
94 not present or cannot be parsed.
95 X509_get0_authority_key_id() returns an internal pointer to the
97 authority key identifier of x as an ASN1_OCTET_STRING or NULL if the
98 extension is not present or cannot be parsed.
99 X509_set_proxy_flag() marks the certificate with the EXFLAG_PROXY flag.
101 This is for the users who need to mark non-RFC3820 proxy certificates
102 as such, as OpenSSL only detects RFC3820 compliant ones.
103 X509_set_proxy_pathlen() sets the proxy certificate path length for the
105 given certificate x. This is for the users who need to mark
106 non-RFC3820 proxy certificates as such, as OpenSSL only detects RFC3820
107 compliant ones.
108 X509_get_proxy_pathlen() returns the proxy certificate path length for
110 the given certificate x if it is a proxy certificate.
111
113 The value of the flags correspond to extension values which are cached
114 in the X509 structure. If the flags returned do not provide sufficient
115 information an application should examine extension values directly for
116 example using X509_get_ext_d2i().
117 If the key usage or extended key usage extension is absent then
119 typically usage is unrestricted. For this reason X509_get_key_usage()
120 and X509_get_extended_key_usage() return UINT32_MAX when the
121 corresponding extension is absent. Applications can additionally check
122 the return value of X509_get_extension_flags() and take appropriate
123 action is an extension is absent.
124 If X509_get0_subject_key_id() returns NULL then the extension may be
126 absent or malformed. Applications can determine the precise reason
127 using X509_get_ext_d2i().
128
130 X509_get_pathlen() returns the path length value, or -1 if the
131 extension is not present.
132 X509_get_extension_flags(), X509_get_key_usage() and
134 X509_get_extended_key_usage() return sets of flags corresponding to the
135 certificate extension values.
136 X509_get0_subject_key_id() returns the subject key identifier as a
138 pointer to an ASN1_OCTET_STRING structure or NULL if the extension is
139 absent or an error occurred during parsing.
140 X509_get_proxy_pathlen() returns the path length value if the given
142 certificate is a proxy one and has a path length set, and -1 otherwise.
143
145 X509_check_purpose(3)
146
148 X509_get_pathlen(), X509_set_proxy_flag(), X509_set_proxy_pathlen() and
149 X509_get_proxy_pathlen() were added in OpenSSL 1.1.0.
150
152 Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.
153 Licensed under the OpenSSL license (the "License"). You may not use
155 this file except in compliance with the License. You can obtain a copy
156 in the file LICENSE in the source distribution or at
157 <https://www.openssl.org/source/license.html>.
1581.1.1c 2019-05-28 X509_GET_EXTENSION_FLAGS(3)