doc/man3/X509_get_extension_flags.pod - third_party/openssl - Git at Google

 =pod

 =head1 NAME

 X509_get0_subject_key_id,
 X509_get0_authority_key_id,
 X509_get0_authority_issuer,
 X509_get0_authority_serial,
 X509_get_pathlen,
 X509_get_extension_flags,
 X509_get_key_usage,
 X509_get_extended_key_usage,
 X509_set_proxy_flag,
 X509_set_proxy_pathlen,
 X509_get_proxy_pathlen - retrieve certificate extension data

 =head1 SYNOPSIS

  #include <openssl/x509v3.h>

  long X509_get_pathlen(X509 *x);
  uint32_t X509_get_extension_flags(X509 *x);
  uint32_t X509_get_key_usage(X509 *x);
  uint32_t X509_get_extended_key_usage(X509 *x);
  const ASN1_OCTET_STRING *X509_get0_subject_key_id(X509 *x);
  const ASN1_OCTET_STRING *X509_get0_authority_key_id(X509 *x);
  const GENERAL_NAMES *X509_get0_authority_issuer(X509 *x);
  const ASN1_INTEGER *X509_get0_authority_serial(X509 *x);
  void X509_set_proxy_flag(X509 *x);
  void X509_set_proxy_pathlen(int l);
  long X509_get_proxy_pathlen(X509 *x);

 =head1 DESCRIPTION

 These functions retrieve information related to commonly used certificate extensions.

 X509_get_pathlen() retrieves the path length extension from a certificate.
 This extension is used to limit the length of a cert chain that may be
 issued from that CA.

 X509_get_extension_flags() retrieves general information about a certificate,
 it will return one or more of the following flags ored together.

 =over 4

 =item B<EXFLAG_V1>

 The certificate is an obsolete version 1 certificate.

 =item B<EXFLAG_BCONS>

 The certificate contains a basic constraints extension.

 =item B<EXFLAG_CA>

 The certificate contains basic constraints and asserts the CA flag.

 =item B<EXFLAG_PROXY>

 The certificate is a valid proxy certificate.

 =item B<EXFLAG_SI>

 The certificate is self issued (that is subject and issuer names match).

 =item B<EXFLAG_SS>

 The subject and issuer names match and extension values imply it is self
 signed.

 =item B<EXFLAG_FRESHEST>

 The freshest CRL extension is present in the certificate.

 =item B<EXFLAG_CRITICAL>

 The certificate contains an unhandled critical extension.

 =item B<EXFLAG_INVALID>

 Some certificate extension values are invalid or inconsistent.
 The certificate should be rejected.
 This bit may also be raised after an out-of-memory error while
 processing the X509 object, so it may not be related to the processed
 ASN1 object itself.

 =item B<EXFLAG_NO_FINGERPRINT>

 Failed to compute the internal SHA1 hash value of the certificate or CRL.
 This may be due to malloc failure or because no SHA1 implementation was found.

 =item B<EXFLAG_INVALID_POLICY>

 The NID_certificate_policies certificate extension is invalid or
 inconsistent. The certificate should be rejected.
 This bit may also be raised after an out-of-memory error while
 processing the X509 object, so it may not be related to the processed
 ASN1 object itself.

 =item B<EXFLAG_KUSAGE>

 The certificate contains a key usage extension. The value can be retrieved
 using X509_get_key_usage().

 =item B<EXFLAG_XKUSAGE>

 The certificate contains an extended key usage extension. The value can be
 retrieved using X509_get_extended_key_usage().

 =back

 X509_get_key_usage() returns the value of the key usage extension.  If key
 usage is present will return zero or more of the flags:
 B<KU_DIGITAL_SIGNATURE>, B<KU_NON_REPUDIATION>, B<KU_KEY_ENCIPHERMENT>,
 B<KU_DATA_ENCIPHERMENT>, B<KU_KEY_AGREEMENT>, B<KU_KEY_CERT_SIGN>,
 B<KU_CRL_SIGN>, B<KU_ENCIPHER_ONLY> or B<KU_DECIPHER_ONLY> corresponding to
 individual key usage bits. If key usage is absent then B<UINT32_MAX> is
 returned.

 X509_get_extended_key_usage() returns the value of the extended key usage
 extension. If extended key usage is present it will return zero or more of the
 flags: B<XKU_SSL_SERVER>, B<XKU_SSL_CLIENT>, B<XKU_SMIME>, B<XKU_CODE_SIGN>
 B<XKU_OCSP_SIGN>, B<XKU_TIMESTAMP>, B<XKU_DVCS> or B<XKU_ANYEKU>. These
 correspond to the OIDs B<id-kp-serverAuth>, B<id-kp-clientAuth>,
 B<id-kp-emailProtection>, B<id-kp-codeSigning>, B<id-kp-OCSPSigning>,
 B<id-kp-timeStamping>, B<id-kp-dvcs> and B<anyExtendedKeyUsage> respectively.
 Additionally B<XKU_SGC> is set if either Netscape or Microsoft SGC OIDs are
 present.

 X509_get0_subject_key_id() returns an internal pointer to the subject key
 identifier of B<x> as an B<ASN1_OCTET_STRING> or B<NULL> if the extension
 is not present or cannot be parsed.

 X509_get0_authority_key_id() returns an internal pointer to the authority key
 identifier of B<x> as an B<ASN1_OCTET_STRING> or B<NULL> if the extension
 is not present or cannot be parsed.

 X509_get0_authority_issuer() returns an internal pointer to the authority
 certificate issuer of B<x> as a stack of B<GENERAL_NAME> structures or
 B<NULL> if the extension is not present or cannot be parsed.

 X509_get0_authority_serial() returns an internal pointer to the authority
 certificate serial number of B<x> as an B<ASN1_INTEGER> or B<NULL> if the
 extension is not present or cannot be parsed.

 X509_set_proxy_flag() marks the certificate with the B<EXFLAG_PROXY> flag.
 This is for the users who need to mark non-RFC3820 proxy certificates as
 such, as OpenSSL only detects RFC3820 compliant ones.

 X509_set_proxy_pathlen() sets the proxy certificate path length for the given
 certificate B<x>.  This is for the users who need to mark non-RFC3820 proxy
 certificates as such, as OpenSSL only detects RFC3820 compliant ones.

 X509_get_proxy_pathlen() returns the proxy certificate path length for the
 given certificate B<x> if it is a proxy certificate.

 =head1 NOTES

 The value of the flags correspond to extension values which are cached
 in the B<X509> structure. If the flags returned do not provide sufficient
 information an application should examine extension values directly
 for example using X509_get_ext_d2i().

 If the key usage or extended key usage extension is absent then typically usage
 is unrestricted. For this reason X509_get_key_usage() and
 X509_get_extended_key_usage() return B<UINT32_MAX> when the corresponding
 extension is absent. Applications can additionally check the return value of
 X509_get_extension_flags() and take appropriate action is an extension is
 absent.

 If X509_get0_subject_key_id() returns B<NULL> then the extension may be
 absent or malformed. Applications can determine the precise reason using
 X509_get_ext_d2i().

 =head1 RETURN VALUES

 X509_get_pathlen() returns the path length value, or -1 if the extension
 is not present.

 X509_get_extension_flags(), X509_get_key_usage() and
 X509_get_extended_key_usage() return sets of flags corresponding to the
 certificate extension values.

 X509_get0_subject_key_id() returns the subject key identifier as a
 pointer to an B<ASN1_OCTET_STRING> structure or B<NULL> if the extension
 is absent or an error occurred during parsing.

 X509_get_proxy_pathlen() returns the path length value if the given
 certificate is a proxy one and has a path length set, and -1 otherwise.

 =head1 SEE ALSO

 L<X509_check_purpose(3)>

 =head1 HISTORY

 X509_get_pathlen(), X509_set_proxy_flag(), X509_set_proxy_pathlen() and
 X509_get_proxy_pathlen() were added in OpenSSL 1.1.0.

 =head1 COPYRIGHT

 Copyright 2015-2021 The OpenSSL Project Authors. All Rights Reserved.

 Licensed under the Apache License 2.0 (the "License").  You may not use
 this file except in compliance with the License.  You can obtain a copy
 in the file LICENSE in the source distribution or at
 L<https://www.openssl.org/source/license.html>.

 =cut
	=pod

	=head1 NAME

	X509_get0_subject_key_id,
	X509_get0_authority_key_id,
	X509_get0_authority_issuer,
	X509_get0_authority_serial,
	X509_get_pathlen,
	X509_get_extension_flags,
	X509_get_key_usage,
	X509_get_extended_key_usage,
	X509_set_proxy_flag,
	X509_set_proxy_pathlen,
	X509_get_proxy_pathlen - retrieve certificate extension data

	=head1 SYNOPSIS

	#include <openssl/x509v3.h>

	long X509_get_pathlen(X509 *x);
	uint32_t X509_get_extension_flags(X509 *x);
	uint32_t X509_get_key_usage(X509 *x);
	uint32_t X509_get_extended_key_usage(X509 *x);
	const ASN1_OCTET_STRING X509_get0_subject_key_id(X509 x);
	const ASN1_OCTET_STRING X509_get0_authority_key_id(X509 x);
	const GENERAL_NAMES X509_get0_authority_issuer(X509 x);
	const ASN1_INTEGER X509_get0_authority_serial(X509 x);
	void X509_set_proxy_flag(X509 *x);
	void X509_set_proxy_pathlen(int l);
	long X509_get_proxy_pathlen(X509 *x);

	=head1 DESCRIPTION

	These functions retrieve information related to commonly used certificate extensions.

	X509_get_pathlen() retrieves the path length extension from a certificate.
	This extension is used to limit the length of a cert chain that may be
	issued from that CA.

	X509_get_extension_flags() retrieves general information about a certificate,
	it will return one or more of the following flags ored together.

	=over 4

	=item B<EXFLAG_V1>

	The certificate is an obsolete version 1 certificate.

	=item B<EXFLAG_BCONS>

	The certificate contains a basic constraints extension.

	=item B<EXFLAG_CA>

	The certificate contains basic constraints and asserts the CA flag.

	=item B<EXFLAG_PROXY>

	The certificate is a valid proxy certificate.

	=item B<EXFLAG_SI>

	The certificate is self issued (that is subject and issuer names match).

	=item B<EXFLAG_SS>

	The subject and issuer names match and extension values imply it is self
	signed.

	=item B<EXFLAG_FRESHEST>

	The freshest CRL extension is present in the certificate.

	=item B<EXFLAG_CRITICAL>

	The certificate contains an unhandled critical extension.

	=item B<EXFLAG_INVALID>

	Some certificate extension values are invalid or inconsistent.
	The certificate should be rejected.
	This bit may also be raised after an out-of-memory error while
	processing the X509 object, so it may not be related to the processed
	ASN1 object itself.

	=item B<EXFLAG_NO_FINGERPRINT>

	Failed to compute the internal SHA1 hash value of the certificate or CRL.
	This may be due to malloc failure or because no SHA1 implementation was found.

	=item B<EXFLAG_INVALID_POLICY>

	The NID_certificate_policies certificate extension is invalid or
	inconsistent. The certificate should be rejected.
	This bit may also be raised after an out-of-memory error while
	processing the X509 object, so it may not be related to the processed
	ASN1 object itself.

	=item B<EXFLAG_KUSAGE>

	The certificate contains a key usage extension. The value can be retrieved
	using X509_get_key_usage().

	=item B<EXFLAG_XKUSAGE>

	The certificate contains an extended key usage extension. The value can be
	retrieved using X509_get_extended_key_usage().

	=back

	X509_get_key_usage() returns the value of the key usage extension. If key
	usage is present will return zero or more of the flags:
	B<KU_DIGITAL_SIGNATURE>, B<KU_NON_REPUDIATION>, B<KU_KEY_ENCIPHERMENT>,
	B<KU_DATA_ENCIPHERMENT>, B<KU_KEY_AGREEMENT>, B<KU_KEY_CERT_SIGN>,
	B<KU_CRL_SIGN>, B<KU_ENCIPHER_ONLY> or B<KU_DECIPHER_ONLY> corresponding to
	individual key usage bits. If key usage is absent then B<UINT32_MAX> is
	returned.

	X509_get_extended_key_usage() returns the value of the extended key usage
	extension. If extended key usage is present it will return zero or more of the
	flags: B<XKU_SSL_SERVER>, B<XKU_SSL_CLIENT>, B<XKU_SMIME>, B<XKU_CODE_SIGN>
	B<XKU_OCSP_SIGN>, B<XKU_TIMESTAMP>, B<XKU_DVCS> or B<XKU_ANYEKU>. These
	correspond to the OIDs B<id-kp-serverAuth>, B<id-kp-clientAuth>,
	B<id-kp-emailProtection>, B<id-kp-codeSigning>, B<id-kp-OCSPSigning>,
	B<id-kp-timeStamping>, B<id-kp-dvcs> and B<anyExtendedKeyUsage> respectively.
	Additionally B<XKU_SGC> is set if either Netscape or Microsoft SGC OIDs are
	present.

	X509_get0_subject_key_id() returns an internal pointer to the subject key
	identifier of B<x> as an B<ASN1_OCTET_STRING> or B<NULL> if the extension
	is not present or cannot be parsed.

	X509_get0_authority_key_id() returns an internal pointer to the authority key
	identifier of B<x> as an B<ASN1_OCTET_STRING> or B<NULL> if the extension
	is not present or cannot be parsed.

	X509_get0_authority_issuer() returns an internal pointer to the authority
	certificate issuer of B<x> as a stack of B<GENERAL_NAME> structures or
	B<NULL> if the extension is not present or cannot be parsed.

	X509_get0_authority_serial() returns an internal pointer to the authority
	certificate serial number of B<x> as an B<ASN1_INTEGER> or B<NULL> if the
	extension is not present or cannot be parsed.

	X509_set_proxy_flag() marks the certificate with the B<EXFLAG_PROXY> flag.
	This is for the users who need to mark non-RFC3820 proxy certificates as
	such, as OpenSSL only detects RFC3820 compliant ones.

	X509_set_proxy_pathlen() sets the proxy certificate path length for the given
	certificate B<x>. This is for the users who need to mark non-RFC3820 proxy
	certificates as such, as OpenSSL only detects RFC3820 compliant ones.

	X509_get_proxy_pathlen() returns the proxy certificate path length for the
	given certificate B<x> if it is a proxy certificate.

	=head1 NOTES

	The value of the flags correspond to extension values which are cached
	in the B<X509> structure. If the flags returned do not provide sufficient
	information an application should examine extension values directly
	for example using X509_get_ext_d2i().

	If the key usage or extended key usage extension is absent then typically usage
	is unrestricted. For this reason X509_get_key_usage() and
	X509_get_extended_key_usage() return B<UINT32_MAX> when the corresponding
	extension is absent. Applications can additionally check the return value of
	X509_get_extension_flags() and take appropriate action is an extension is
	absent.

	If X509_get0_subject_key_id() returns B<NULL> then the extension may be
	absent or malformed. Applications can determine the precise reason using
	X509_get_ext_d2i().

	=head1 RETURN VALUES

	X509_get_pathlen() returns the path length value, or -1 if the extension
	is not present.

	X509_get_extension_flags(), X509_get_key_usage() and
	X509_get_extended_key_usage() return sets of flags corresponding to the
	certificate extension values.

	X509_get0_subject_key_id() returns the subject key identifier as a
	pointer to an B<ASN1_OCTET_STRING> structure or B<NULL> if the extension
	is absent or an error occurred during parsing.

	X509_get_proxy_pathlen() returns the path length value if the given
	certificate is a proxy one and has a path length set, and -1 otherwise.

	=head1 SEE ALSO

	L<X509_check_purpose(3)>

	=head1 HISTORY

	X509_get_pathlen(), X509_set_proxy_flag(), X509_set_proxy_pathlen() and
	X509_get_proxy_pathlen() were added in OpenSSL 1.1.0.

	=head1 COPYRIGHT

	Copyright 2015-2021 The OpenSSL Project Authors. All Rights Reserved.

	Licensed under the Apache License 2.0 (the "License"). You may not use
	this file except in compliance with the License. You can obtain a copy
	in the file LICENSE in the source distribution or at
	L<https://www.openssl.org/source/license.html>.

	=cut