1 #include "os.h"
2 #include <mp.h>
3 #include <libsec.h>
4 
5 /*  generate a probable prime.  accuracy is the miller-rabin interations */
6 void
7 genprime(mpint *p, int n, int accuracy)
8 {
9 	mpdigit x;
10 
11 	/* generate n random bits with high and low bits set */
12 	mpbits(p, n);
13 	genrandom((uchar*)p->p, (n+7)/8);
14 	p->top = (n+Dbits-1)/Dbits;
15 	x = 1;
16 	x <<= ((n-1)%Dbits);
17 	p->p[p->top-1] &= (x-1);
18 	p->p[p->top-1] |= x;
19 	p->p[0] |= 1;
20 
21 	/* keep icrementing till it looks prime */
22 	for(;;){
23 		if(probably_prime(p, accuracy))
24 			break;
25 		mpadd(p, mptwo, p);
26 	}
27 }