]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * include/linux/random.h | |
3 | * | |
4 | * Include file for the random number generator. | |
5 | */ | |
1da177e4 LT |
6 | #ifndef _LINUX_RANDOM_H |
7 | #define _LINUX_RANDOM_H | |
8 | ||
205a525c | 9 | #include <linux/list.h> |
607ca46e | 10 | #include <uapi/linux/random.h> |
1da177e4 | 11 | |
205a525c HX |
12 | struct random_ready_callback { |
13 | struct list_head list; | |
14 | void (*func)(struct random_ready_callback *rdy); | |
15 | struct module *owner; | |
16 | }; | |
17 | ||
a2080a67 | 18 | extern void add_device_randomness(const void *, unsigned int); |
1da177e4 LT |
19 | extern void add_input_randomness(unsigned int type, unsigned int code, |
20 | unsigned int value); | |
775f4b29 | 21 | extern void add_interrupt_randomness(int irq, int irq_flags); |
1da177e4 LT |
22 | |
23 | extern void get_random_bytes(void *buf, int nbytes); | |
205a525c HX |
24 | extern int add_random_ready_callback(struct random_ready_callback *rdy); |
25 | extern void del_random_ready_callback(struct random_ready_callback *rdy); | |
c2557a30 | 26 | extern void get_random_bytes_arch(void *buf, int nbytes); |
1da177e4 | 27 | void generate_random_uuid(unsigned char uuid_out[16]); |
47d06e53 | 28 | extern int random_int_secret_init(void); |
1da177e4 | 29 | |
1da177e4 | 30 | #ifndef MODULE |
54047320 | 31 | extern const struct file_operations random_fops, urandom_fops; |
1da177e4 LT |
32 | #endif |
33 | ||
34 | unsigned int get_random_int(void); | |
35 | unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len); | |
36 | ||
496f2f93 | 37 | u32 prandom_u32(void); |
a98406e2 | 38 | void prandom_bytes(void *buf, size_t nbytes); |
496f2f93 | 39 | void prandom_seed(u32 seed); |
4af712e8 | 40 | void prandom_reseed_late(void); |
aaa248f6 | 41 | |
38e9efcd | 42 | struct rnd_state { |
a98814ce | 43 | __u32 s1, s2, s3, s4; |
38e9efcd DB |
44 | }; |
45 | ||
a98814ce | 46 | u32 prandom_u32_state(struct rnd_state *state); |
a98406e2 | 47 | void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes); |
5960164f | 48 | |
f337db64 DB |
49 | /** |
50 | * prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro) | |
51 | * @ep_ro: right open interval endpoint | |
52 | * | |
53 | * Returns a pseudo-random number that is in interval [0, ep_ro). Note | |
54 | * that the result depends on PRNG being well distributed in [0, ~0U] | |
55 | * u32 space. Here we use maximally equidistributed combined Tausworthe | |
56 | * generator, that is, prandom_u32(). This is useful when requesting a | |
57 | * random index of an array containing ep_ro elements, for example. | |
58 | * | |
59 | * Returns: pseudo-random number in interval [0, ep_ro) | |
60 | */ | |
61 | static inline u32 prandom_u32_max(u32 ep_ro) | |
62 | { | |
63 | return (u32)(((u64) prandom_u32() * ep_ro) >> 32); | |
64 | } | |
65 | ||
5960164f JE |
66 | /* |
67 | * Handle minimum values for seeds | |
68 | */ | |
69 | static inline u32 __seed(u32 x, u32 m) | |
70 | { | |
71 | return (x < m) ? x + m : x; | |
72 | } | |
73 | ||
74 | /** | |
496f2f93 | 75 | * prandom_seed_state - set seed for prandom_u32_state(). |
5960164f JE |
76 | * @state: pointer to state structure to receive the seed. |
77 | * @seed: arbitrary 64-bit value to use as a seed. | |
78 | */ | |
496f2f93 | 79 | static inline void prandom_seed_state(struct rnd_state *state, u64 seed) |
5960164f JE |
80 | { |
81 | u32 i = (seed >> 32) ^ (seed << 10) ^ seed; | |
82 | ||
a98814ce DB |
83 | state->s1 = __seed(i, 2U); |
84 | state->s2 = __seed(i, 8U); | |
85 | state->s3 = __seed(i, 16U); | |
86 | state->s4 = __seed(i, 128U); | |
5960164f JE |
87 | } |
88 | ||
63d77173 PA |
89 | #ifdef CONFIG_ARCH_RANDOM |
90 | # include <asm/archrandom.h> | |
91 | #else | |
92 | static inline int arch_get_random_long(unsigned long *v) | |
93 | { | |
94 | return 0; | |
95 | } | |
96 | static inline int arch_get_random_int(unsigned int *v) | |
97 | { | |
98 | return 0; | |
99 | } | |
7b878d4b PA |
100 | static inline int arch_has_random(void) |
101 | { | |
102 | return 0; | |
103 | } | |
d20f78d2 PA |
104 | static inline int arch_get_random_seed_long(unsigned long *v) |
105 | { | |
106 | return 0; | |
107 | } | |
108 | static inline int arch_get_random_seed_int(unsigned int *v) | |
109 | { | |
110 | return 0; | |
111 | } | |
7b878d4b PA |
112 | static inline int arch_has_random_seed(void) |
113 | { | |
114 | return 0; | |
115 | } | |
63d77173 PA |
116 | #endif |
117 | ||
055dc21a TH |
118 | /* Pseudo random number generator from numerical recipes. */ |
119 | static inline u32 next_pseudo_random32(u32 seed) | |
120 | { | |
121 | return seed * 1664525 + 1013904223; | |
122 | } | |
123 | ||
1da177e4 | 124 | #endif /* _LINUX_RANDOM_H */ |