NAME

       gnutls_certificate_set_retrieve_function2 - API function

SYNOPSIS

       #include <gnutls/abstract.h>

       void           gnutls_certificate_set_retrieve_function2(gnutls_certificate_credentials_t           cred,
       gnutls_certificate_retrieve_function2 * func);

ARGUMENTS

       gnutls_certificate_credentials_t cred
                   is a gnutls_certificate_credentials_t type.

       gnutls_certificate_retrieve_function2 * func
                   is the callback function

DESCRIPTION

       This function sets a callback to be called in order to  retrieve  the  certificate  to  be  used  in  the
       handshake. The callback will take control only if a certificate is requested by the peer.

       The  callback's function prototype is: int (*callback)(gnutls_session_t, const gnutls_datum_t* req_ca_dn,
       int nreqs, const gnutls_pk_algorithm_t* pk_algos, int pk_algos_length, gnutls_pcert_st** pcert,  unsigned
       int *pcert_length, gnutls_privkey_t * pkey);

        req_ca_dn  is  only  used  in  X.509  certificates.   Contains  a list with the CA names that the server
       considers trusted.  This is a hint and typically the client should send a certificate that is  signed  by
       one  of  these  CAs. These names, when available, are DER encoded. To get a more meaningful value use the
       function gnutls_x509_rdn_get().

        pk_algos contains a list with server's acceptable  public  key  algorithms.   The  certificate  returned
       should support the server's given algorithms.

        pcert should contain a single certificate and public key or a list of them.

        pcert_length is the size of the previous list.

        pkey is the private key.

       If  the  callback  function is provided then gnutls will call it, in the handshake, after the certificate
       request message has been received.  All the provided by the callback  values  will  not  be  released  or
       modified by gnutls.

       In server side pk_algos and req_ca_dn are NULL.

       The  callback  function  should  set  the  certificate  list  to  be sent, and return 0 on success. If no
       certificate was selected then the number of certificates should be set to zero. The value (-1)  indicates
       error  and  the  handshake  will  be  terminated.  If  both certificates are set in the credentials and a
       callback is available, the callback takes predence.

SINCE

       3.0

REPORTING BUGS

       Report bugs to <bugs@gnutls.org>.
       Home page: http://www.gnutls.org

COPYRIGHT

       Copyright © 2001-2022 Free Software Foundation, Inc., and others.
       Copying and distribution of this file, with or without modification, are permitted in any medium  without
       royalty provided the copyright notice and this notice are preserved.

SEE ALSO

       The  full  documentation  for  gnutls  is  maintained as a Texinfo manual.  If the /usr/share/doc/gnutls/
       directory does not contain the HTML form visit

       http://www.gnutls.org/manual/