Thanks for the interest, i resolved with EC_POINT_invert(). EC-Elgamal work fine :)
Il giorno ven, 04/07/2008 alle 11.56 -0600, Bill Colvin ha scritto: > Pietro: OpenSSL seems to provide add, double, invert and multiply > routines for EC points. There does not seem to be an explicit routine > for subtract in the include files. > > The book "Implementing Eliptic Curve Cryptography" by Michael Rosing has > routines esub and poly_esub for doing a subtraction of two EC points > depending on the type of underlying curve. Essentially these routines > first perform a negation of the subtrahend followed by an addition. > > Bill > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Pietro Albano > Sent: July 4, 2008 10:17 AM > To: openssl-users@openssl.org > Subject: Subtract betwen two EC_POINT > > Hi all, > I'm newby on openssl coding, I developing Elgamal chiper , i need > subtract two EC_POINT who can help me? > > ______________________________________________________________________ > OpenSSL Project http://www.openssl.org > User Support Mailing List openssl-users@openssl.org > Automated List Manager [EMAIL PROTECTED] > ______________________________________________________________________ > OpenSSL Project http://www.openssl.org > User Support Mailing List openssl-users@openssl.org > Automated List Manager [EMAIL PROTECTED] ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager [EMAIL PROTECTED]
