/* Internal function to return processed entropy from the PRNG */
int
read_random_real(void *buf, int count)
{
static int cur = 0;
static int gate = 1;
static u_char genval[KEYSIZE];
size_t tomove;
int i;
int retval;
/* The reseed task must not be jumped on */
mtx_lock(&random_reseed_mtx);
if (gate) {
generator_gate();
random_state.outputblocks = 0;
gate = 0;
}
if (count > 0 && (size_t)count >= sizeof(random_state.counter)) {
retval = 0;
for (i = 0; i < count; i += (int)sizeof(random_state.counter)) {
random_state.counter[0]++;
yarrow_encrypt(&random_state.key, random_state.counter,
genval);
tomove = min(count - i, sizeof(random_state.counter));
memcpy((char *)buf + i, genval, tomove);
if (++random_state.outputblocks >=
random_state.gengateinterval) {
generator_gate();
random_state.outputblocks = 0;
}
retval += (int)tomove;
}
}
else {
if (!cur) {
random_state.counter[0]++;
yarrow_encrypt(&random_state.key, random_state.counter,
genval);
memcpy(buf, genval, (size_t)count);
cur = (int)sizeof(random_state.counter) - count;
if (++random_state.outputblocks >=
random_state.gengateinterval) {
generator_gate();
random_state.outputblocks = 0;
}
retval = count;
}
else {
retval = cur < count ? cur : count;
memcpy(buf,
&genval[(int)sizeof(random_state.counter) - cur],
(size_t)retval);
cur -= retval;
}
}
mtx_unlock(&random_reseed_mtx);
return retval;
}
/* Internal function to return processed entropy from the PRNG */
int
random_yarrow_read(void *buf, int count)
{
static int cur = 0;
static int gate = 1;
static uint8_t genval[KEYSIZE];
size_t tomove;
int i;
int retval;
/* Check for final read request */
if (buf == NULL && count == 0)
return (0);
/* The reseed task must not be jumped on */
mtx_lock(&random_reseed_mtx);
if (gate) {
generator_gate();
random_state.outputblocks = 0;
gate = 0;
}
if (count > 0 && (size_t)count >= BLOCKSIZE) {
retval = 0;
for (i = 0; i < count; i += BLOCKSIZE) {
increment_counter();
randomdev_encrypt(&random_state.key, random_state.counter.byte, genval, BLOCKSIZE);
tomove = MIN(count - i, BLOCKSIZE);
memcpy((char *)buf + i, genval, tomove);
if (++random_state.outputblocks >= random_state.gengateinterval) {
generator_gate();
random_state.outputblocks = 0;
}
retval += (int)tomove;
cur = 0;
}
}
else {
if (!cur) {
increment_counter();
randomdev_encrypt(&random_state.key, random_state.counter.byte, genval, BLOCKSIZE);
memcpy(buf, genval, (size_t)count);
cur = BLOCKSIZE - count;
if (++random_state.outputblocks >= random_state.gengateinterval) {
generator_gate();
random_state.outputblocks = 0;
}
retval = count;
}
else {
retval = MIN(cur, count);
memcpy(buf, &genval[BLOCKSIZE - cur], (size_t)retval);
cur -= retval;
}
}
mtx_unlock(&random_reseed_mtx);
return (retval);
}
