/* SPDX-License-Identifier: LGPL-2.1+ */
#pragma once
-/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
-int acquire_random_bytes(void *p, size_t n, bool high_quality_required);
-void pseudorandom_bytes(void *p, size_t n);
-void random_bytes(void *p, size_t n);
+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_MAY_FAIL = 1 << 2, /* If we can't get any randomness at all, return early with -ENODATA */
+ RANDOM_ALLOW_RDRAND = 1 << 3, /* Allow usage of the CPU RNG */
+ RANDOM_ALLOW_INSECURE = 1 << 4, /* Allow usage of GRND_INSECURE flag to kernel's getrandom() API */
+} RandomFlags;
+
+int genuine_random_bytes(void *p, size_t n, RandomFlags flags); /* returns "genuine" randomness, optionally filled up with 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) {
random_bytes(&u, sizeof(u));
return u;
}
+
+int rdrand(unsigned long *ret);
+
+/* Some limits on the pool sizes when we deal with the kernel random pool */
+#define RANDOM_POOL_SIZE_MIN 512U
+#define RANDOM_POOL_SIZE_MAX (10U*1024U*1024U)
+
+size_t random_pool_size(void);
+
+int random_write_entropy(int fd, const void *seed, size_t size, bool credit);