34 lines
1.4 KiB
C
34 lines
1.4 KiB
C
/* SPDX-License-Identifier: LGPL-2.1+ */
|
|
#pragma once
|
|
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
typedef enum RandomFlags {
|
|
RANDOM_EXTEND_WITH_PSEUDO = 1 << 0, /* If we can't get enough genuine randomness, but some, fill up the rest with pseudo-randomness */
|
|
RANDOM_BLOCK = 1 << 1, /* Rather block than return crap randomness (only if the kernel supports that) */
|
|
RANDOM_DONT_DRAIN = 1 << 2, /* If we can't get any randomness at all, return early with -EAGAIN */
|
|
RANDOM_ALLOW_RDRAND = 1 << 3, /* Allow usage of the CPU RNG */
|
|
} RandomFlags;
|
|
|
|
int genuine_random_bytes(void *p, size_t n, RandomFlags flags); /* returns "genuine" randomness, optionally filled upwith pseudo random, if not enough is available */
|
|
void pseudo_random_bytes(void *p, size_t n); /* returns only pseudo-randommess (but possibly seeded from something better) */
|
|
void random_bytes(void *p, size_t n); /* returns genuine randomness if cheaply available, and pseudo randomness if not. */
|
|
|
|
void initialize_srand(void);
|
|
|
|
static inline uint64_t random_u64(void) {
|
|
uint64_t u;
|
|
random_bytes(&u, sizeof(u));
|
|
return u;
|
|
}
|
|
|
|
static inline uint32_t random_u32(void) {
|
|
uint32_t u;
|
|
random_bytes(&u, sizeof(u));
|
|
return u;
|
|
}
|
|
|
|
int rdrand(unsigned long *ret);
|