6f48921cd5
The previous formatting did not immediately stabilize, and the resulting formatting is somewhat arbitrary. Manually inserting linebreaks seems to make more sense.
71 lines
1.5 KiB
C
71 lines
1.5 KiB
C
/**
|
|
* WARNING
|
|
*
|
|
* This file generates a PREDICTABLE and NOT AT ALL RANDOM sequence of bytes.
|
|
*
|
|
* Its purpose is to support our testing suite and it MUST NOT be used in any
|
|
* scenario where you are expecting actual cryptography to happen.
|
|
*/
|
|
|
|
#include "randombytes.h"
|
|
#include <stdint.h>
|
|
|
|
static uint32_t seed[32] = {3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9, 3,
|
|
2, 3, 8, 4, 6, 2, 6, 4, 3, 3, 8, 3, 2, 7, 9, 5};
|
|
static uint32_t in[12];
|
|
static uint32_t out[8];
|
|
static int32_t outleft = 0;
|
|
|
|
#define ROTATE(x, b) (((x) << (b)) | ((x) >> (32 - (b))))
|
|
#define MUSH(i, b) x = t[i] += (((x ^ seed[i]) + sum) ^ ROTATE(x, b));
|
|
|
|
static void surf(void) {
|
|
uint32_t t[12];
|
|
uint32_t x;
|
|
uint32_t sum = 0;
|
|
int32_t r;
|
|
int32_t i;
|
|
int32_t loop;
|
|
|
|
for (i = 0; i < 12; ++i)
|
|
t[i] = in[i] ^ seed[12 + i];
|
|
for (i = 0; i < 8; ++i)
|
|
out[i] = seed[24 + i];
|
|
x = t[11];
|
|
for (loop = 0; loop < 2; ++loop) {
|
|
for (r = 0; r < 16; ++r) {
|
|
sum += 0x9e3779b9;
|
|
MUSH(0, 5)
|
|
MUSH(1, 7)
|
|
MUSH(2, 9)
|
|
MUSH(3, 13)
|
|
MUSH(4, 5)
|
|
MUSH(5, 7)
|
|
MUSH(6, 9)
|
|
MUSH(7, 13)
|
|
MUSH(8, 5)
|
|
MUSH(9, 7)
|
|
MUSH(10, 9)
|
|
MUSH(11, 13)
|
|
}
|
|
for (i = 0; i < 8; ++i)
|
|
out[i] ^= t[i + 4];
|
|
}
|
|
}
|
|
|
|
void randombytes(uint8_t *x, uint64_t xlen) {
|
|
while (xlen > 0) {
|
|
if (!outleft) {
|
|
if (!++in[0])
|
|
if (!++in[1])
|
|
if (!++in[2])
|
|
++in[3];
|
|
surf();
|
|
outleft = 8;
|
|
}
|
|
*x = out[--outleft];
|
|
++x;
|
|
--xlen;
|
|
}
|
|
}
|