/*
* update pools
*/
static void
add_entropy(FState * st, const uint8 *data, unsigned len)
{
unsigned pos;
uint8 hash[BLOCK];
MD_CTX md;
/* hash given data */
md_init(&md);
md_update(&md, data, len);
md_result(&md, hash);
/*
* Make sure the pool 0 is initialized, then update randomly.
*/
if (st->reseed_count == 0 && st->pool0_bytes < POOL0_FILL)
pos = 0;
else
pos = get_rand_pool(st);
md_update(&st->pool[pos], hash, BLOCK);
if (pos == 0)
st->pool0_bytes += len;
memset(hash, 0, BLOCK);
memset(&md, 0, sizeof(md));
}
/*
* update pools
*/
static void add_entropy(FState *st, const uint8_t *data, unsigned len)
{
unsigned pos;
uint8_t hash[block];
mdCtx md;
/* hash given data */
md_init(&md);
md_update(&md, data, len);
md_result(&md, hash);
/*
* Make sure the pool 0 is initialized, then update randomly.
*/
if (st->reseedCount == 0)
pos = 0;
else
pos = get_rand_pool(st);
md_update(&st->pool[pos], hash, block);
if (pos == 0)
st->pool0Bytes += len;
memset(hash, 0, block);
memset(&md, 0, sizeof(md));
}
/*
* generate new key from all the pools
*/
static void
reseed(FState * st)
{
unsigned k;
unsigned n;
MD_CTX key_md;
unsigned char buf[BLOCK];
/* set pool as empty */
st->pool0_bytes = 0;
/*
* Both #0 and #1 reseed would use only pool 0. Just skip #0 then.
*/
n = ++st->reseed_count;
/*
* The goal: use k-th pool only 1/(2^k) of the time.
*/
md_init(&key_md);
for (k = 0; k < NUM_POOLS; k++)
{
md_result(&st->pool[k], buf);
md_update(&key_md, buf, BLOCK);
if (n & 1 || !n)
break;
n >>= 1;
}
/* add old key into mix too */
md_update(&key_md, st->key, BLOCK);
/* add pid to make output diverse after fork() */
md_update(&key_md, (const unsigned char *)&st->pid, sizeof(st->pid));
/* now we have new key */
md_result(&key_md, st->key);
/* use new key */
ciph_init(&st->ciph, st->key, BLOCK);
memset(&key_md, 0, sizeof(key_md));
memset(buf, 0, BLOCK);
}
/*
* generate new key from all the pools
*/
static void reseed(FState *st)
{
unsigned k;
unsigned n;
mdCtx key_md;
uint8_t buf[block];
/* set pool as empty */
st->pool0Bytes = 0;
/*
* Both #0 and #1 reseed would use only pool 0. Just skip #0 then.
*/
n = ++st->reseedCount;
/*
* The goal: use k-th pool only 1/(2^k) of the time.
*/
md_init(&key_md);
for (k = 0; k < numPools; k++) {
md_result(&st->pool[k], buf);
md_update(&key_md, buf, block);
if (n & 1 || !n)
break;
n >>= 1;
}
/* add old key into mix too */
md_update(&key_md, st->key, block);
/* now we have new key */
md_result(&key_md, st->key);
/* use new key */
ciph_init(&st->ciph, st->key, block);
memset(&key_md, 0, sizeof(key_md));
memset(buf, 0, block);
}
