1 0fc65b37 2004-03-21 devnull #include "os.h"
 2 0fc65b37 2004-03-21 devnull #include <mp.h>
 3 0fc65b37 2004-03-21 devnull #include <libsec.h>
 4 0fc65b37 2004-03-21 devnull 
 5 0fc65b37 2004-03-21 devnull mpint*
 6 0fc65b37 2004-03-21 devnull egencrypt(EGpub *pub, mpint *in, mpint *out)
 7 0fc65b37 2004-03-21 devnull {
 8 0fc65b37 2004-03-21 devnull 	mpint *m, *k, *gamma, *delta, *pm1;
 9 0fc65b37 2004-03-21 devnull 	mpint *p = pub->p, *alpha = pub->alpha;
10 0fc65b37 2004-03-21 devnull 	int plen = mpsignif(p);
11 0fc65b37 2004-03-21 devnull 	int shift = ((plen+Dbits)/Dbits)*Dbits;
12 cbeb0b26 2006-04-01 devnull 	/* in libcrypt version, (int)(LENGTH(pub->p)*sizeof(NumType)*CHARBITS); */
13 0fc65b37 2004-03-21 devnull 
14 0fc65b37 2004-03-21 devnull 	if(out == nil)
15 0fc65b37 2004-03-21 devnull 		out = mpnew(0);
16 0fc65b37 2004-03-21 devnull 	pm1 = mpnew(0);
17 0fc65b37 2004-03-21 devnull 	m = mpnew(0);
18 0fc65b37 2004-03-21 devnull 	gamma = mpnew(0);
19 0fc65b37 2004-03-21 devnull 	delta = mpnew(0);
20 0fc65b37 2004-03-21 devnull 	mpmod(in, p, m);
21 0fc65b37 2004-03-21 devnull 	while(1){
22 0fc65b37 2004-03-21 devnull 		k = mprand(plen, genrandom, nil);
23 0fc65b37 2004-03-21 devnull 		if((mpcmp(mpone, k) <= 0) && (mpcmp(k, pm1) < 0))
24 0fc65b37 2004-03-21 devnull 			break;
25 0fc65b37 2004-03-21 devnull 	}
26 0fc65b37 2004-03-21 devnull 	mpexp(alpha, k, p, gamma);
27 0fc65b37 2004-03-21 devnull 	mpexp(pub->key, k, p, delta);
28 0fc65b37 2004-03-21 devnull 	mpmul(m, delta, delta);
29 0fc65b37 2004-03-21 devnull 	mpmod(delta, p, delta);
30 0fc65b37 2004-03-21 devnull 	mpleft(gamma, shift, out);
31 0fc65b37 2004-03-21 devnull 	mpadd(delta, out, out);
32 0fc65b37 2004-03-21 devnull 	mpfree(pm1);
33 0fc65b37 2004-03-21 devnull 	mpfree(m);
34 0fc65b37 2004-03-21 devnull 	mpfree(k);
35 0fc65b37 2004-03-21 devnull 	mpfree(gamma);
36 0fc65b37 2004-03-21 devnull 	mpfree(delta);
37 0fc65b37 2004-03-21 devnull 	return out;
38 0fc65b37 2004-03-21 devnull }