/** Generate a pseudo-random number.
* This uses the #localkey structure plus current time as input to
* MD5, feeding most of the MD5 output back to #localkey and using one
* output words as the pseudo-random output.
* @return A 32-bit pseudo-random number.
*/
unsigned int ircrandom(void)
{
struct timeval tv;
char usec[3];
/* Add some randomness to the pool. */
gettimeofday(&tv, 0);
usec[0] = tv.tv_usec;
usec[1] = tv.tv_usec >> 8;
usec[2] = tv.tv_usec >> 16;
random_add_entropy(usec, 3);
/* Perform MD5 step. */
localkey.buf[0] = 0x67452301;
localkey.buf[1] = 0xefcdab89;
localkey.buf[2] = 0x98badcfe;
localkey.buf[3] = 0x10325476;
MD5Transform(localkey.buf, (uint32*)localkey.in);
/* Feed back 12 bytes of hash value into randomness pool. */
random_add_entropy((char*)localkey.buf, 12);
/* Return the final word of hash, which should not provide any
* useful insight into current pool contents. */
return localkey.buf[3];
}
/*ARGSUSED*/
static int
rnd_write(dev_t dev, struct uio *uiop, cred_t *credp)
{
int error;
uint8_t buf[WRITEBUFSIZE];
size_t bytes;
minor_t devno;
devno = getminor(dev);
while (uiop->uio_resid > 0) {
bytes = min(sizeof (buf), uiop->uio_resid);
/* See comments in rnd_read() */
uiop->uio_loffset = 0;
if ((error = uiomove(buf, bytes, UIO_WRITE, uiop)) != 0)
return (error);
switch (devno) {
case DEVRANDOM:
if ((error = random_add_entropy(buf, bytes, 0)) != 0)
return (error);
break;
case DEVURANDOM:
if ((error = random_add_pseudo_entropy(buf, bytes,
0)) != 0)
return (error);
break;
default:
return (ENXIO);
}
}
return (0);
}
static void event_handler(switch_event_t *event)
{
char *buf;
if (switch_event_serialize(event, &buf, SWITCH_TRUE) == SWITCH_STATUS_SUCCESS) {
random_add_entropy(rfd, buf, strlen(buf));
free(buf);
}
}
/** Seed the PRNG with a string.
* @param[in] from Client setting the seed (may be NULL).
* @param[in] fields Input arguments (fields[0] is used).
* @param[in] count Number of input arguments.
* @return Non-zero on success, zero on error.
*/
int
random_seed_set(struct Client* from, const char* const* fields, int count)
{
if (count < 1) {
if (from) /* send an error */
return need_more_params(from, "SET");
else {
log_write(LS_CONFIG, L_ERROR, 0, "Not enough fields in F line");
return 0;
}
}
random_add_entropy(fields[0], strlen(fields[0]));
return 1;
}
