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#include "os.h"
#include <libsec.h>
static void
init(Chachastate *cs)
{
ulong seed[11];
int i;
for(i=0; i<nelem(seed); i++)
seed[i] = truerand();
setupChachastate(cs, (uchar*)&seed[0], 32, (uchar*)&seed[8], 12, 20);
memset(seed, 0, sizeof(seed));
}
static void
fill(Chachastate *cs, uchar *p, int n)
{
Chachastate c;
c = *cs;
chacha_encrypt((uchar*)&cs->input[4], 32, &c);
if(++cs->input[13] == 0)
if(++cs->input[14] == 0)
++cs->input[15];
chacha_encrypt(p, n, &c);
memset(&c, 0, sizeof(c));
}
void
genrandom(uchar *p, int n)
{
static QLock lk;
static Chachastate cs;
qlock(&lk);
if(cs.rounds == 0)
init(&cs);
cs.input[4] ^= getpid(); /* fork protection */
fill(&cs, p, n);
qunlock(&lk);
}
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