1 /*
2 * include/linux/random.h
3 *
4 * Include file for the random number generator.
5 */
6
7 #ifndef _LINUX_RANDOM_H
8 #define _LINUX_RANDOM_H
9
10 #include <linux/types.h>
11 #include <linux/ioctl.h>
12 #include <linux/irqnr.h>
13
14 /* ioctl()'s for the random number generator */
15
16 /* Get the entropy count. */
17 #define RNDGETENTCNT _IOR( 'R', 0x00, int )
18
19 /* Add to (or subtract from) the entropy count. (Superuser only.) */
20 #define RNDADDTOENTCNT _IOW( 'R', 0x01, int )
21
22 /* Get the contents of the entropy pool. (Superuser only.) */
23 #define RNDGETPOOL _IOR( 'R', 0x02, int [2] )
24
25 /*
26 * Write bytes into the entropy pool and add to the entropy count.
27 * (Superuser only.)
28 */
29 #define RNDADDENTROPY _IOW( 'R', 0x03, int [2] )
30
31 /* Clear entropy count to 0. (Superuser only.) */
32 #define RNDZAPENTCNT _IO( 'R', 0x04 )
33
34 /* Clear the entropy pool and associated counters. (Superuser only.) */
35 #define RNDCLEARPOOL _IO( 'R', 0x06 )
36
37 struct rand_pool_info {
38 int entropy_count;
39 int buf_size;
40 __u32 buf[0];
41 };
42
43 struct rnd_state {
44 __u32 s1, s2, s3;
45 };
46
47 /* Exported functions */
48
49 #ifdef __KERNEL__
50
51 extern void add_device_randomness(const void *, unsigned int);
52 extern void add_input_randomness(unsigned int type, unsigned int code,
53 unsigned int value);
54 extern void add_interrupt_randomness(int irq, int irq_flags);
55
56 extern void get_random_bytes(void *buf, int nbytes);
57 extern void get_random_bytes_arch(void *buf, int nbytes);
58 void generate_random_uuid(unsigned char uuid_out[16]);
59 extern int random_int_secret_init(void);
60
61 #ifndef MODULE
62 extern const struct file_operations random_fops, urandom_fops;
63 #endif
64
65 unsigned int get_random_int(void);
66 unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
67
68 u32 random32(void);
69 void srandom32(u32 seed);
70
71 u32 prandom32(struct rnd_state *);
72
73 /*
74 * Handle minimum values for seeds
75 */
__seed(u32 x,u32 m)76 static inline u32 __seed(u32 x, u32 m)
77 {
78 return (x < m) ? x + m : x;
79 }
80
81 /**
82 * prandom32_seed - set seed for prandom32().
83 * @state: pointer to state structure to receive the seed.
84 * @seed: arbitrary 64-bit value to use as a seed.
85 */
prandom32_seed(struct rnd_state * state,u64 seed)86 static inline void prandom32_seed(struct rnd_state *state, u64 seed)
87 {
88 u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
89
90 state->s1 = __seed(i, 2);
91 state->s2 = __seed(i, 8);
92 state->s3 = __seed(i, 16);
93 }
94
95 #ifdef CONFIG_ARCH_RANDOM
96 # include <asm/archrandom.h>
97 #else
arch_get_random_long(unsigned long * v)98 static inline int arch_get_random_long(unsigned long *v)
99 {
100 return 0;
101 }
arch_get_random_int(unsigned int * v)102 static inline int arch_get_random_int(unsigned int *v)
103 {
104 return 0;
105 }
106 #endif
107
108 #endif /* __KERNEL___ */
109
110 #endif /* _LINUX_RANDOM_H */
111