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x509(3ssl)


NAME

   x509 - X.509 certificate handling

SYNOPSIS

    #include <openssl/x509.h>

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.

   X509_..., d2i_X509_... and i2d_X509_... handle X.509 certificates, with
   some exceptions, shown below.

   X509_CRL_..., d2i_X509_CRL_... and i2d_X509_CRL_...  handle X.509 CRLs.

   X509_REQ_..., d2i_X509_REQ_... and i2d_X509_REQ_...  handle PKCS#10
   certificate requests.

   X509_NAME_... handle certificate names.

   X509_ATTRIBUTE_... handle certificate attributes.

   X509_EXTENSION_... 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), crypto(3), x509v3(3)



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