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 */ 84