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 cbeb0b26 2006-04-01 devnull /*  generate a probable prime.  accuracy is the miller-rabin interations */
 6 0fc65b37 2004-03-21 devnull void
 7 0fc65b37 2004-03-21 devnull genprime(mpint *p, int n, int accuracy)
 8 0fc65b37 2004-03-21 devnull {
 9 0fc65b37 2004-03-21 devnull 	mpdigit x;
10 0fc65b37 2004-03-21 devnull 
11 cbeb0b26 2006-04-01 devnull 	/* generate n random bits with high and low bits set */
12 0fc65b37 2004-03-21 devnull 	mpbits(p, n);
13 0fc65b37 2004-03-21 devnull 	genrandom((uchar*)p->p, (n+7)/8);
14 0fc65b37 2004-03-21 devnull 	p->top = (n+Dbits-1)/Dbits;
15 0fc65b37 2004-03-21 devnull 	x = 1;
16 0fc65b37 2004-03-21 devnull 	x <<= ((n-1)%Dbits);
17 0fc65b37 2004-03-21 devnull 	p->p[p->top-1] &= (x-1);
18 0fc65b37 2004-03-21 devnull 	p->p[p->top-1] |= x;
19 0fc65b37 2004-03-21 devnull 	p->p[0] |= 1;
20 0fc65b37 2004-03-21 devnull 
21 cbeb0b26 2006-04-01 devnull 	/* keep icrementing till it looks prime */
22 0fc65b37 2004-03-21 devnull 	for(;;){
23 0fc65b37 2004-03-21 devnull 		if(probably_prime(p, accuracy))
24 0fc65b37 2004-03-21 devnull 			break;
25 0fc65b37 2004-03-21 devnull 		mpadd(p, mptwo, p);
26 0fc65b37 2004-03-21 devnull 	}
27 0fc65b37 2004-03-21 devnull }