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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * include/linux/random.h
3 *
4 * Include file for the random number generator.
5 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07006#ifndef _LINUX_RANDOM_H
7#define _LINUX_RANDOM_H
8
David Howells607ca462012-10-13 10:46:48 +01009#include <uapi/linux/random.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
Linus Torvaldsa2080a62012-07-04 11:16:01 -040012extern void add_device_randomness(const void *, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070013extern void add_input_randomness(unsigned int type, unsigned int code,
14 unsigned int value);
Theodore Ts'o775f4b22012-07-02 07:52:16 -040015extern void add_interrupt_randomness(int irq, int irq_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070016
17extern void get_random_bytes(void *buf, int nbytes);
Theodore Ts'oc2557a32012-07-05 10:35:23 -040018extern void get_random_bytes_arch(void *buf, int nbytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -070019void generate_random_uuid(unsigned char uuid_out[16]);
20
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#ifndef MODULE
Arjan van de Ven54047322007-02-12 00:55:28 -080022extern const struct file_operations random_fops, urandom_fops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#endif
24
25unsigned int get_random_int(void);
26unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
27
Akinobu Mita496f2f92012-12-17 16:04:23 -080028u32 prandom_u32(void);
Akinobu Mita6582c662012-12-17 16:04:25 -080029void prandom_bytes(void *buf, int nbytes);
Akinobu Mita496f2f92012-12-17 16:04:23 -080030void prandom_seed(u32 seed);
Stephen Hemmingeraaa248f2006-10-17 00:09:42 -070031
Akinobu Mita496f2f92012-12-17 16:04:23 -080032/*
33 * These macros are preserved for backward compatibility and should be
34 * removed as soon as a transition is finished.
35 */
36#define random32() prandom_u32()
37#define srandom32(seed) prandom_seed(seed)
38
39u32 prandom_u32_state(struct rnd_state *);
Akinobu Mita6582c662012-12-17 16:04:25 -080040void prandom_bytes_state(struct rnd_state *state, void *buf, int nbytes);
Joe Eykholt59601642010-05-26 14:44:13 -070041
42/*
43 * Handle minimum values for seeds
44 */
45static inline u32 __seed(u32 x, u32 m)
46{
47 return (x < m) ? x + m : x;
48}
49
50/**
Akinobu Mita496f2f92012-12-17 16:04:23 -080051 * prandom_seed_state - set seed for prandom_u32_state().
Joe Eykholt59601642010-05-26 14:44:13 -070052 * @state: pointer to state structure to receive the seed.
53 * @seed: arbitrary 64-bit value to use as a seed.
54 */
Akinobu Mita496f2f92012-12-17 16:04:23 -080055static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
Joe Eykholt59601642010-05-26 14:44:13 -070056{
57 u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
58
59 state->s1 = __seed(i, 1);
60 state->s2 = __seed(i, 7);
61 state->s3 = __seed(i, 15);
62}
63
H. Peter Anvin63d77172011-07-31 13:54:50 -070064#ifdef CONFIG_ARCH_RANDOM
65# include <asm/archrandom.h>
66#else
67static inline int arch_get_random_long(unsigned long *v)
68{
69 return 0;
70}
71static inline int arch_get_random_int(unsigned int *v)
72{
73 return 0;
74}
75#endif
76
Tom Herbert055dc212013-01-22 09:49:50 +000077/* Pseudo random number generator from numerical recipes. */
78static inline u32 next_pseudo_random32(u32 seed)
79{
80 return seed * 1664525 + 1013904223;
81}
82
Linus Torvalds1da177e2005-04-16 15:20:36 -070083#endif /* _LINUX_RANDOM_H */