Provided by: openssl_1.1.1-1ubuntu2.1~18.04.23_amd64 

NAME
x509 - X.509 certificate handling
SYNOPSIS
#include <openssl/x509.h>
DESCRIPTION
An X.509 certificate is a structured grouping of information about an individual, a device, or anything
one can imagine. A X.509 CRL (certificate revocation list) is a tool to help determine if a certificate
is still valid. The exact definition of those can be found in the X.509 document from ITU-T, or in
RFC3280 from PKIX. In OpenSSL, the type X509 is used to express such a certificate, and the type
X509_CRL is used to express a CRL.
A related structure is a certificate request, defined in PKCS#10 from RSA Security, Inc, also reflected
in RFC2896. In OpenSSL, the type X509_REQ is used to express such a certificate request.
To handle some complex parts of a certificate, there are the types X509_NAME (to express a certificate
name), X509_ATTRIBUTE (to express a certificate attributes), X509_EXTENSION (to express a certificate
extension) and a few more.
Finally, there's the supertype X509_INFO, which can contain a CRL, a certificate and a corresponding
private key.
X509_XXX, d2i_X509_XXX, and i2d_X509_XXX functions handle X.509 certificates, with some exceptions, shown
below.
X509_CRL_XXX, d2i_X509_CRL_XXX, and i2d_X509_CRL_XXX functions handle X.509 CRLs.
X509_REQ_XXX, d2i_X509_REQ_XXX, and i2d_X509_REQ_XXX functions handle PKCS#10 certificate requests.
X509_NAME_XXX functions handle certificate names.
X509_ATTRIBUTE_XXX functions handle certificate attributes.
X509_EXTENSION_XXX functions handle certificate extensions.
SEE ALSO
X509_NAME_ENTRY_get_object(3), X509_NAME_add_entry_by_txt(3), X509_NAME_add_entry_by_NID(3),
X509_NAME_print_ex(3), X509_NAME_new(3), d2i_X509(3), d2i_X509_ALGOR(3), d2i_X509_CRL(3),
d2i_X509_NAME(3), d2i_X509_REQ(3), d2i_X509_SIG(3), X509v3(3), crypto(7)
COPYRIGHT
Copyright 2003-2017 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (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
<https://www.openssl.org/source/license.html>.
1.1.1 2023-05-24 X509(7SSL)