A document that has a very rough description of the X509

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=head1 NAME

x509 - X.509 certificate handling

=head1 SYNOPSIS

 #include <openssl/x509.h>

=head1 DESCRIPTION

A 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.

B<X509_>I<...>, B<d2i_X509_>I<...> and B<i2d_X509_>I<...> handle X.509

certificates, with some exceptions, shown below.

B<X509_CRL_>I<...>, B<d2i_X509_CRL_>I<...> and B<i2d_X509_CRL_>I<...>

handle X.509 CRLs.

B<X509_REQ_>I<...>, B<d2i_X509_REQ_>I<...> and B<i2d_X509_REQ_>I<...>

handle PKCS#10 certificate requests.

B<X509_NAME_>I<...> handle certificate names.

B<X509_ATTRIBUTE_>I<...> handle certificate attributes.

B<X509_EXTENSION_>I<...> handle certificate extensions.

=head1 SEE ALSO

L<X509_NAME_ENTRY_get_object(3)|X509_NAME_ENTRY_get_object(3)>,

L<X509_NAME_add_entry_by_txt(3)|X509_NAME_add_entry_by_txt(3)>,

L<X509_NAME_add_entry_by_NID(3)|X509_NAME_add_entry_by_NID(3)>,

L<X509_NAME_print_ex(3)|X509_NAME_print_ex(3)>,

L<X509_NAME_new(3)|X509_NAME_new(3)>,

L<d2i_X509(3)|d2i_X509(3)>,

L<d2i_X509_ALGOR(3)|d2i_X509_ALGOR(3)>,

L<d2i_X509_CRL(3)|d2i_X509_CRL(3)>,

L<d2i_X509_NAME(3)|d2i_X509_NAME(3)>,

L<d2i_X509_REQ(3)|d2i_X509_REQ(3)>,

L<d2i_X509_SIG(3)|d2i_X509_SIG(3)>,

L<crypto(3)|crypto(3)>,

L<x509v3(3)|x509v3(3)>

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