NAME

     fido_cred_exclude, fido_cred_empty_exclude_list — manage exclude lists in a FIDO2 credential

SYNOPSIS

     #include <fido.h>

     int
     fido_cred_exclude(fido_cred_t *cred, const unsigned char *ptr, size_t len);

     int
     fido_cred_empty_exclude_list(fido_cred_t *cred);

DESCRIPTION

     The fido_cred_exclude() function adds ptr to the list of credentials excluded by cred, where
     ptr points to a credential ID of len bytes.  A copy of ptr is made, and no references to the
     passed pointer are kept.  If fido_cred_exclude() fails, the existing list of excluded
     credentials is preserved.

     If fido_cred_exclude returns success and cred is later passed to fido_dev_make_cred(3) on a
     device that contains the credential denoted by ptr, then fido_dev_make_cred(3) will fail.

     For the format of a FIDO2 credential ID, please refer to the Web Authentication (webauthn)
     standard.

     The fido_cred_empty_exclude_list() function empties the list of credentials excluded by
     cred.

RETURN VALUES

     The error codes returned by fido_cred_exclude() and fido_cred_empty_exclude_list() are
     defined in <fido/err.h>.  On success, FIDO_OK is returned.

SEE ALSO

     fido_cred_new(3), fido_cred_set_authdata(3), fido_dev_make_cred(3)