- NAME
- SYNOPSIS
- DESCRIPTION
- SEE ALSO
- COPYRIGHT

# 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. An 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 attribute), 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 2003-2021 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.