=pod =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)> =cut