1*8ccd4a63SDavid du Colombier #include "os.h"
2*8ccd4a63SDavid du Colombier #include <mp.h>
3*8ccd4a63SDavid du Colombier #include <libsec.h>
4*8ccd4a63SDavid du Colombier
5*8ccd4a63SDavid du Colombier mpint*
egencrypt(EGpub * pub,mpint * in,mpint * out)6*8ccd4a63SDavid du Colombier egencrypt(EGpub *pub, mpint *in, mpint *out)
7*8ccd4a63SDavid du Colombier {
8*8ccd4a63SDavid du Colombier mpint *m, *k, *gamma, *delta, *pm1;
9*8ccd4a63SDavid du Colombier mpint *p = pub->p, *alpha = pub->alpha;
10*8ccd4a63SDavid du Colombier int plen = mpsignif(p);
11*8ccd4a63SDavid du Colombier int shift = ((plen+Dbits)/Dbits)*Dbits;
12*8ccd4a63SDavid du Colombier // in libcrypt version, (int)(LENGTH(pub->p)*sizeof(NumType)*CHARBITS);
13*8ccd4a63SDavid du Colombier
14*8ccd4a63SDavid du Colombier if(out == nil)
15*8ccd4a63SDavid du Colombier out = mpnew(0);
16*8ccd4a63SDavid du Colombier pm1 = mpnew(0);
17*8ccd4a63SDavid du Colombier m = mpnew(0);
18*8ccd4a63SDavid du Colombier gamma = mpnew(0);
19*8ccd4a63SDavid du Colombier delta = mpnew(0);
20*8ccd4a63SDavid du Colombier mpmod(in, p, m);
21*8ccd4a63SDavid du Colombier while(1){
22*8ccd4a63SDavid du Colombier k = mprand(plen, genrandom, nil);
23*8ccd4a63SDavid du Colombier if((mpcmp(mpone, k) <= 0) && (mpcmp(k, pm1) < 0))
24*8ccd4a63SDavid du Colombier break;
25*8ccd4a63SDavid du Colombier }
26*8ccd4a63SDavid du Colombier mpexp(alpha, k, p, gamma);
27*8ccd4a63SDavid du Colombier mpexp(pub->key, k, p, delta);
28*8ccd4a63SDavid du Colombier mpmul(m, delta, delta);
29*8ccd4a63SDavid du Colombier mpmod(delta, p, delta);
30*8ccd4a63SDavid du Colombier mpleft(gamma, shift, out);
31*8ccd4a63SDavid du Colombier mpadd(delta, out, out);
32*8ccd4a63SDavid du Colombier mpfree(pm1);
33*8ccd4a63SDavid du Colombier mpfree(m);
34*8ccd4a63SDavid du Colombier mpfree(k);
35*8ccd4a63SDavid du Colombier mpfree(gamma);
36*8ccd4a63SDavid du Colombier mpfree(delta);
37*8ccd4a63SDavid du Colombier return out;
38*8ccd4a63SDavid du Colombier }
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