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#include <string.h>
#include "kernelrandombytes.h"
#include "crypto_rng.h"
#include "randombytes.h"
unsigned long long randombytes_calls = 0;
unsigned long long randombytes_bytes = 0;
static unsigned int init = 0;
static unsigned char g[crypto_rng_KEYBYTES];
static unsigned char r[crypto_rng_OUTPUTBYTES];
unsigned long long pos = crypto_rng_OUTPUTBYTES;
void randombytes(unsigned char *x,unsigned long long xlen)
{
randombytes_calls += 1;
randombytes_bytes += xlen;
if (!init) {
kernelrandombytes(g,sizeof g);
init = 1;
}
#ifdef SIMPLE
while (xlen > 0) {
if (pos == crypto_rng_OUTPUTBYTES) {
crypto_rng(r,g,g);
pos = 0;
}
*x++ = r[pos]; xlen -= 1;
r[pos++] = 0;
}
#else /* same output but optimizing copies */
while (xlen > 0) {
unsigned long long ready;
if (pos == crypto_rng_OUTPUTBYTES) {
while (xlen > crypto_rng_OUTPUTBYTES) {
crypto_rng(x,g,g);
x += crypto_rng_OUTPUTBYTES;
xlen -= crypto_rng_OUTPUTBYTES;
}
if (xlen == 0) return;
crypto_rng(r,g,g);
pos = 0;
}
ready = crypto_rng_OUTPUTBYTES - pos;
if (xlen <= ready) ready = xlen;
memcpy(x,r + pos,ready);
memset(r + pos,0,ready);
x += ready;
xlen -= ready;
pos += ready;
}
#endif
}
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