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| author | Sebastien Bacher <seb128@ubuntu.com> | 2019-01-25 11:26:25 +0100 |
|---|---|---|
| committer | Sebastien Bacher <seb128@ubuntu.com> | 2019-01-25 11:26:25 +0100 |
| commit | f54a568880bf47c2ea54c9b30d291156b34d6539 (patch) | |
| tree | aab9bb44b306da7651e8caf38bbab5cfeeb81b7d /shared/systemd/src/basic/random-util.h | |
| parent | e8ac7dacdcf4b38addef4f8ac6ab038f9d29582c (diff) | |
| parent | bbae86d3d2997a853ca0365e8eb7a3ca7489ee09 (diff) | |
Update upstream source from tag 'upstream/1.15.2'
Update to upstream version '1.15.2' with Debian dir b4be4b7cfce96679a31cb9d423107789761e3b49
Diffstat (limited to 'shared/systemd/src/basic/random-util.h')
| -rw-r--r-- | shared/systemd/src/basic/random-util.h | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/shared/systemd/src/basic/random-util.h b/shared/systemd/src/basic/random-util.h new file mode 100644 index 00000000..3e8c288d --- /dev/null +++ b/shared/systemd/src/basic/random-util.h @@ -0,0 +1,33 @@ +/* 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); |