include/linux/random.h

   1 /*
   2  * include/linux/random.h
   3  *
   4  * Include file for the random number generator.
   5  */
   6 #ifndef _LINUX_RANDOM_H
   7 #define _LINUX_RANDOM_H
   8
   9 #include <uapi/linux/random.h>
  10
  11
  12 extern void add_device_randomness(const void *, unsigned int);
  13 extern void add_input_randomness(unsigned int type, unsigned int code,
  14                                  unsigned int value);
  15 extern void add_interrupt_randomness(int irq, int irq_flags);
  16
  17 extern void get_random_bytes(void *buf, int nbytes);
  18 extern void get_random_bytes_arch(void *buf, int nbytes);
  19 void generate_random_uuid(unsigned char uuid_out[16]);
  20 extern int random_int_secret_init(void);
  21
  22 #ifndef MODULE
  23 extern const struct file_operations random_fops, urandom_fops;
  24 #endif
  25
  26 unsigned int get_random_int(void);
  27 unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
  28
  29 u32 prandom_u32(void);
  30 void prandom_bytes(void *buf, int nbytes);
  31 void prandom_seed(u32 seed);
  32 void prandom_reseed_late(void);
  33
  34 struct rnd_state {
  35         __u32 s1, s2, s3, s4;
  36 };
  37
  38 u32 prandom_u32_state(struct rnd_state *state);
  39 void prandom_bytes_state(struct rnd_state *state, void *buf, int nbytes);
  40
  41 /*
  42  * Handle minimum values for seeds
  43  */
  44 static inline u32 __seed(u32 x, u32 m)
  45 {
  46         return (x < m) ? x + m : x;
  47 }
  48
  49 /**
  50  * prandom_seed_state - set seed for prandom_u32_state().
  51  * @state: pointer to state structure to receive the seed.
  52  * @seed: arbitrary 64-bit value to use as a seed.
  53  */
  54 static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
  55 {
  56         u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
  57
  58         state->s1 = __seed(i,   2U);
  59         state->s2 = __seed(i,   8U);
  60         state->s3 = __seed(i,  16U);
  61         state->s4 = __seed(i, 128U);
  62 }
  63
  64 #ifdef CONFIG_ARCH_RANDOM
  65 # include <asm/archrandom.h>
  66 #else
  67 static inline int arch_get_random_long(unsigned long *v)
  68 {
  69         return 0;
  70 }
  71 static inline int arch_get_random_int(unsigned int *v)
  72 {
  73         return 0;
  74 }
  75 #endif
  76
  77 /* Pseudo random number generator from numerical recipes. */
  78 static inline u32 next_pseudo_random32(u32 seed)
  79 {
  80         return seed * 1664525 + 1013904223;
  81 }
  82
  83 #endif /* _LINUX_RANDOM_H */