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#include "os.h"
#include <mp.h>
#include <libsec.h>
mpint*
egencrypt(EGpub *pub, mpint *in, mpint *out)
{
mpint *m, *k, *gamma, *delta, *pm1;
mpint *p = pub->p, *alpha = pub->alpha;
int plen = mpsignif(p);
int shift = ((plen+Dbits)/Dbits)*Dbits;
/* in libcrypt version, (int)(LENGTH(pub->p)*sizeof(NumType)*CHARBITS); */
if(out == nil)
out = mpnew(0);
pm1 = mpnew(0);
m = mpnew(0);
gamma = mpnew(0);
delta = mpnew(0);
mpmod(in, p, m);
while(1){
k = mprand(plen, genrandom, nil);
if((mpcmp(mpone, k) <= 0) && (mpcmp(k, pm1) < 0))
break;
}
mpexp(alpha, k, p, gamma);
mpexp(pub->key, k, p, delta);
mpmul(m, delta, delta);
mpmod(delta, p, delta);
mpleft(gamma, shift, out);
mpadd(delta, out, out);
mpfree(pm1);
mpfree(m);
mpfree(k);
mpfree(gamma);
mpfree(delta);
return out;
}
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