forsyth20121205-174063a80cc13 years agoHistory
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#include "os.h"#include <mp.h>#include <libsec.h> mpint*egdecrypt(EGpriv *priv, mpint *in, mpint *out){	EGpub *pub = &priv->pub;	mpint *gamma, *delta;	mpint *p = pub->p;	int plen = mpsignif(p)+1;	int shift = ((plen+Dbits-1)/Dbits)*Dbits; 	if(out == nil)		out = mpnew(0);	gamma = mpnew(0);	delta = mpnew(0);	mpright(in, shift, gamma);	mpleft(gamma, shift, delta);	mpsub(in, delta, delta);		mpexp(gamma, priv->secret, p, out);	mpinvert(out, p, gamma);	mpmul(gamma, delta, out);	mpmod(out, p, out);	mpfree(gamma);	mpfree(delta);	return out;}