gnutls_hpke_open(3)                 gnutls                 gnutls_hpke_open(3)

NAME
       gnutls_hpke_open - API function

SYNOPSIS
       #include <gnutls/hpke.h>

       int gnutls_hpke_open(gnutls_hpke_context_t ctx, const gnutls_datum_t *
       aad, const gnutls_datum_t * ciphertext, gnutls_datum_t * plaintext);

ARGUMENTS
       gnutls_hpke_context_t ctx
                   The HPKE context to use for opening.

       const gnutls_datum_t * aad
                   The associated data (AAD) that was authenticated during
                   sealing.

       const gnutls_datum_t * ciphertext
                   The ciphertext received from the sender.

       gnutls_datum_t * plaintext
                   A pointer to a gnutls_datum_t structure where the resulting
                   plaintext will be stored.

DESCRIPTION
       This function performs the opening operation of HPKE. It takes the
       ciphertext received from the sender and uses the keys and nonces set up
       in the HPKE context (after decapsulation) to decrypt the ciphertext and
       verify the authentication tag. If the decryption and authentication are
       successful, the resulting plaintext is stored in
        plaintext . If the decryption or authentication fails, the function
       securely erases any allocated plaintext and returns an error code.

       This function can be used multiple times with the same HPKE context,
       but the decapsulation function (gnutls_hpke_decap()) must be called
       once before the first call to this function.

        aad should be the same AAD that was provided to gnutls_hpke_seal() on
       the sender's side.

        ciphertext should be the same ciphertext that was generated by
       gnutls_hpke_seal() on the sender's side.

       The function will allocate memory for the  plaintext , and the caller
       is responsible for freeing this memory using gnutls_free() when it is
       no longer needed.

RETURNS
       0 on success, or a negative error code on failure

SINCE
       3.8.13

REPORTING BUGS
       Report bugs to <bugs@gnutls.org>.
       Home page: https://www.gnutls.org


COPYRIGHT
       Copyright (C) 2001-2023 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

       https://www.gnutls.org/manual/

gnutls                              3.8.13                 gnutls_hpke_open(3)