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#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "rnd.h"
#include "die.h"
#include "ioexact.h"
#include "ioops.h"
static int fdw = -1;
static void randombytes_weak(unsigned char *x, size_t xlen)
{
int ret;
if (fdw == -1) {
for (;;) {
fdw = open(LOW_ENTROPY_SOURCE, O_RDONLY);
if (fdw != -1)
break;
sleep(1);
}
}
while (xlen > 0) {
if (xlen < 1048576)
ret = xlen;
else
ret = 1048576;
ret = read(fdw, x, ret);
if (ret < 1) {
sleep(1);
continue;
}
x += ret;
xlen -= ret;
}
}
static void randombytes_strong(unsigned char *x, size_t xlen)
{
int fds, ret;
fds = open_or_die(HIG_ENTROPY_SOURCE, O_RDONLY);
ret = read_exact(fds, x, xlen, 0);
if (ret != (int) xlen)
panic("Error reading from entropy source!\n");
close(fds);
}
int secrand(void)
{
int ret;
randombytes_weak((void *) &ret, sizeof(ret));
return ret;
}
void gen_key_bytes(unsigned char *area, size_t len)
{
randombytes_strong(area, len);
}
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