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8021q: fix a potential memory leak
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1da177e4
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1/*
2 * include/linux/random.h
3 *
4 * Include file for the random number generator.
5 */
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6#ifndef _LINUX_RANDOM_H
7#define _LINUX_RANDOM_H
8
607ca46e 9#include <uapi/linux/random.h>
1da177e4 10
a2080a67 11extern void add_device_randomness(const void *, unsigned int);
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12extern void add_input_randomness(unsigned int type, unsigned int code,
13 unsigned int value);
775f4b29 14extern void add_interrupt_randomness(int irq, int irq_flags);
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15
16extern void get_random_bytes(void *buf, int nbytes);
c2557a30 17extern void get_random_bytes_arch(void *buf, int nbytes);
1da177e4 18void generate_random_uuid(unsigned char uuid_out[16]);
47d06e53 19extern int random_int_secret_init(void);
1da177e4 20
1da177e4 21#ifndef MODULE
54047320 22extern const struct file_operations random_fops, urandom_fops;
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23#endif
24
25unsigned int get_random_int(void);
26unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);
27
496f2f93 28u32 prandom_u32(void);
6582c665 29void prandom_bytes(void *buf, int nbytes);
496f2f93 30void prandom_seed(u32 seed);
4af712e8 31void prandom_reseed_late(void);
aaa248f6 32
38e9efcd 33struct rnd_state {
a98814ce 34 __u32 s1, s2, s3, s4;
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35};
36
a98814ce 37u32 prandom_u32_state(struct rnd_state *state);
6582c665 38void prandom_bytes_state(struct rnd_state *state, void *buf, int nbytes);
5960164f 39
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40/**
41 * prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro)
42 * @ep_ro: right open interval endpoint
43 *
44 * Returns a pseudo-random number that is in interval [0, ep_ro). Note
45 * that the result depends on PRNG being well distributed in [0, ~0U]
46 * u32 space. Here we use maximally equidistributed combined Tausworthe
47 * generator, that is, prandom_u32(). This is useful when requesting a
48 * random index of an array containing ep_ro elements, for example.
49 *
50 * Returns: pseudo-random number in interval [0, ep_ro)
51 */
52static inline u32 prandom_u32_max(u32 ep_ro)
53{
54 return (u32)(((u64) prandom_u32() * ep_ro) >> 32);
55}
56
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57/*
58 * Handle minimum values for seeds
59 */
60static inline u32 __seed(u32 x, u32 m)
61{
62 return (x < m) ? x + m : x;
63}
64
65/**
496f2f93 66 * prandom_seed_state - set seed for prandom_u32_state().
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67 * @state: pointer to state structure to receive the seed.
68 * @seed: arbitrary 64-bit value to use as a seed.
69 */
496f2f93 70static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
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71{
72 u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
73
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74 state->s1 = __seed(i, 2U);
75 state->s2 = __seed(i, 8U);
76 state->s3 = __seed(i, 16U);
77 state->s4 = __seed(i, 128U);
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78}
79
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80#ifdef CONFIG_ARCH_RANDOM
81# include <asm/archrandom.h>
82#else
83static inline int arch_get_random_long(unsigned long *v)
84{
85 return 0;
86}
87static inline int arch_get_random_int(unsigned int *v)
88{
89 return 0;
90}
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91static inline int arch_has_random(void)
92{
93 return 0;
94}
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95static inline int arch_get_random_seed_long(unsigned long *v)
96{
97 return 0;
98}
99static inline int arch_get_random_seed_int(unsigned int *v)
100{
101 return 0;
102}
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103static inline int arch_has_random_seed(void)
104{
105 return 0;
106}
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107#endif
108
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109/* Pseudo random number generator from numerical recipes. */
110static inline u32 next_pseudo_random32(u32 seed)
111{
112 return seed * 1664525 + 1013904223;
113}
114
1da177e4 115#endif /* _LINUX_RANDOM_H */