a2080a67ab
Add a new interface, add_device_randomness() for adding data to the random pool that is likely to differ between two devices (or possibly even per boot). This would be things like MAC addresses or serial numbers, or the read-out of the RTC. This does *not* add any actual entropy to the pool, but it initializes the pool to different values for devices that might otherwise be identical and have very little entropy available to them (particularly common in the embedded world). [ Modified by tytso to mix in a timestamp, since there may be some variability caused by the time needed to detect/configure the hardware in question. ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
111 lines
2.4 KiB
C
111 lines
2.4 KiB
C
/*
|
|
* include/linux/random.h
|
|
*
|
|
* Include file for the random number generator.
|
|
*/
|
|
|
|
#ifndef _LINUX_RANDOM_H
|
|
#define _LINUX_RANDOM_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/ioctl.h>
|
|
#include <linux/irqnr.h>
|
|
|
|
/* ioctl()'s for the random number generator */
|
|
|
|
/* Get the entropy count. */
|
|
#define RNDGETENTCNT _IOR( 'R', 0x00, int )
|
|
|
|
/* Add to (or subtract from) the entropy count. (Superuser only.) */
|
|
#define RNDADDTOENTCNT _IOW( 'R', 0x01, int )
|
|
|
|
/* Get the contents of the entropy pool. (Superuser only.) */
|
|
#define RNDGETPOOL _IOR( 'R', 0x02, int [2] )
|
|
|
|
/*
|
|
* Write bytes into the entropy pool and add to the entropy count.
|
|
* (Superuser only.)
|
|
*/
|
|
#define RNDADDENTROPY _IOW( 'R', 0x03, int [2] )
|
|
|
|
/* Clear entropy count to 0. (Superuser only.) */
|
|
#define RNDZAPENTCNT _IO( 'R', 0x04 )
|
|
|
|
/* Clear the entropy pool and associated counters. (Superuser only.) */
|
|
#define RNDCLEARPOOL _IO( 'R', 0x06 )
|
|
|
|
struct rand_pool_info {
|
|
int entropy_count;
|
|
int buf_size;
|
|
__u32 buf[0];
|
|
};
|
|
|
|
struct rnd_state {
|
|
__u32 s1, s2, s3;
|
|
};
|
|
|
|
/* Exported functions */
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
extern void rand_initialize_irq(int irq);
|
|
|
|
extern void add_device_randomness(const void *, unsigned int);
|
|
extern void add_input_randomness(unsigned int type, unsigned int code,
|
|
unsigned int value);
|
|
extern void add_interrupt_randomness(int irq, int irq_flags);
|
|
|
|
extern void get_random_bytes(void *buf, int nbytes);
|
|
void generate_random_uuid(unsigned char uuid_out[16]);
|
|
|
|
#ifndef MODULE
|
|
extern const struct file_operations random_fops, urandom_fops;
|
|
#endif
|
|
|
|
unsigned int get_random_int(void);
|
|
unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
|
|
|
|
u32 random32(void);
|
|
void srandom32(u32 seed);
|
|
|
|
u32 prandom32(struct rnd_state *);
|
|
|
|
/*
|
|
* Handle minimum values for seeds
|
|
*/
|
|
static inline u32 __seed(u32 x, u32 m)
|
|
{
|
|
return (x < m) ? x + m : x;
|
|
}
|
|
|
|
/**
|
|
* prandom32_seed - set seed for prandom32().
|
|
* @state: pointer to state structure to receive the seed.
|
|
* @seed: arbitrary 64-bit value to use as a seed.
|
|
*/
|
|
static inline void prandom32_seed(struct rnd_state *state, u64 seed)
|
|
{
|
|
u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
|
|
|
|
state->s1 = __seed(i, 1);
|
|
state->s2 = __seed(i, 7);
|
|
state->s3 = __seed(i, 15);
|
|
}
|
|
|
|
#ifdef CONFIG_ARCH_RANDOM
|
|
# include <asm/archrandom.h>
|
|
#else
|
|
static inline int arch_get_random_long(unsigned long *v)
|
|
{
|
|
return 0;
|
|
}
|
|
static inline int arch_get_random_int(unsigned int *v)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#endif /* __KERNEL___ */
|
|
|
|
#endif /* _LINUX_RANDOM_H */
|