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>.