/* -*-c-*-
*
- * $Id: share.c,v 1.6 2001/02/03 16:05:41 mdw Exp $
+ * $Id: share.c,v 1.7 2004/04/08 01:36:15 mdw Exp $
*
* Shamir's secret sharing
*
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: share.c,v $
- * Revision 1.6 2001/02/03 16:05:41 mdw
- * Now @mp_drop@ checks its argument is non-NULL before attempting to free
- * it. Note that the macro version @MP_DROP@ doesn't do this.
- *
- * Revision 1.5 2000/12/06 20:30:10 mdw
- * Change secret sharing interface: present the secret at share
- * construction time.
- *
- * Revision 1.4 2000/10/08 12:16:17 mdw
- * Use @MP_EQ@ instead of @MP_CMP@.
- *
- * Revision 1.3 2000/06/24 18:29:05 mdw
- * Interface change: allow shares to be extracted from a context on demand,
- * rather than building them all up-front.
- *
- * Revision 1.2 2000/06/18 23:05:19 mdw
- * Minor performance tweak: use Barrett reduction rather than Montgomery.
- * Fast secret sharing isn't done here, though: see `gfshare' instead.
- *
- * Revision 1.1 2000/06/17 12:09:38 mdw
- * Shamir's secret sharing system.
- *
- */
-
/*----- Header files ------------------------------------------------------*/
#include <stdio.h>
m = mp_sub(m, &ii, &jj);
m = mp_sub(m, s->p, m);
}
- mp_gcd(0, 0, &m, s->p, m);
+ m = mp_modinv(m, m, s->p);
c = mp_mul(c, c, &jj);
c = mpbarrett_reduce(&mb, c, c);
c = mp_mul(c, c, m);