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 rand_initialize_irq(int irq);
52
53 extern void add_input_randomness(unsigned int type, unsigned int code,
54 unsigned int value);
55 extern void add_interrupt_randomness(int irq);
56
57 extern void get_random_bytes(void *buf, int nbytes);
58 void generate_random_uuid(unsigned char uuid_out[16]);
59
60 extern __u32 secure_ip_id(__be32 daddr);
61 extern u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport);
62 extern u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr,
63 __be16 dport);
64 extern __u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
65 __be16 sport, __be16 dport);
66 extern __u32 secure_tcpv6_sequence_number(__be32 *saddr, __be32 *daddr,
67 __be16 sport, __be16 dport);
68 extern u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr,
69 __be16 sport, __be16 dport);
70
71 #ifndef MODULE
72 extern const struct file_operations random_fops, urandom_fops;
73 #endif
74
75 unsigned int get_random_int(void);
76 unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
77
78 u32 random32(void);
79 void srandom32(u32 seed);
80
81 u32 prandom32(struct rnd_state *);
82
83 /*
84 * Handle minimum values for seeds
85 */
__seed(u32 x,u32 m)86 static inline u32 __seed(u32 x, u32 m)
87 {
88 return (x < m) ? x + m : x;
89 }
90
91 /**
92 * prandom32_seed - set seed for prandom32().
93 * @state: pointer to state structure to receive the seed.
94 * @seed: arbitrary 64-bit value to use as a seed.
95 */
prandom32_seed(struct rnd_state * state,u64 seed)96 static inline void prandom32_seed(struct rnd_state *state, u64 seed)
97 {
98 u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
99
100 state->s1 = __seed(i, 1);
101 state->s2 = __seed(i, 7);
102 state->s3 = __seed(i, 15);
103 }
104
105 #endif /* __KERNEL___ */
106
107 #endif /* _LINUX_RANDOM_H */
108