int dmarc_process();
uschar *dmarc_exim_expand_query(int);
uschar *dmarc_exim_expand_defaults(int);
-uschar *dmarc_auth_results_header(header_line *,uschar *);
-#define DMARC_AR_HEADER US"Authentication-Results:"
#define DMARC_VERIFY_STATUS 1
#define DMARC_HIST_OK 1