NAME

       gnutls_prf_rfc5705 - API function

SYNOPSIS

       #include <gnutls/gnutls.h>

       int  gnutls_prf_rfc5705(gnutls_session_t  session,  size_t label_size, const char * label,
       size_t context_size, const char * context, size_t outsize, char * out);

ARGUMENTS

       gnutls_session_t session
                   is a gnutls_session_t type.

       size_t label_size
                   length of the  label variable.

       const char * label
                   label used in PRF computation, typically a short string.

       size_t context_size
                   length of the  extra variable.

       const char * context
                   optional extra data to seed the PRF with.

       size_t outsize
                   size of pre-allocated output buffer to hold the output.

       char * out  pre-allocated buffer to hold the generated data.

DESCRIPTION

       Applies the TLS Pseudo-Random-Function (PRF) on the master secret and the  provided  data,
       seeded with the client and server random fields, as specified in RFC5705.

       The  label variable usually contains a string denoting the purpose for the generated data.
       The  server_random_first indicates whether the client random field or  the  server  random
       field  should  be  first  in the seed.  Non-zero indicates that the server random field is
       first, 0 that the client random field is first.

       The  context variable can be used  to  add  more  data  to  the  seed,  after  the  random
       variables.  It can be used to make sure the generated output is strongly connected to some
       additional data (e.g., a string used in user authentication).

       The output is placed in  out , which must be pre-allocated.

       Note that, to provide the RFC5705 context, the  contect variable must be non-null.

RETURNS

       GNUTLS_E_SUCCESS on success, or an error code.

SINCE

       3.4.4

REPORTING BUGS

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

COPYRIGHT

       Copyright © 2001-2021 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/