[PATCH] rename net_random to random32

Make net_random() more widely available by calling it random32

akpm: hopefully this will permit the removal of carta_random32.  That needs
confirmation from Stephane - this code looks somewhat more computationally
expensive, and has a different (ie: callee-stateful) interface.

[akpm@osdl.org: lots of build fixes, cleanups]
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Stephane Eranian <eranian@hpl.hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Stephen Hemminger 2006-10-17 00:09:42 -07:00 committed by Linus Torvalds
parent 0187f879ee
commit aaa248f6c9
6 changed files with 150 additions and 122 deletions

View File

@ -19,6 +19,7 @@
#define _LINUX_NET_H
#include <linux/wait.h>
#include <linux/random.h>
#include <asm/socket.h>
struct poll_table_struct;
@ -193,9 +194,9 @@ extern int sock_map_fd(struct socket *sock);
extern struct socket *sockfd_lookup(int fd, int *err);
#define sockfd_put(sock) fput(sock->file)
extern int net_ratelimit(void);
extern unsigned long net_random(void);
extern void net_srandom(unsigned long);
extern void net_random_init(void);
#define net_random() random32()
#define net_srandom(seed) srandom32(seed)
extern int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
struct kvec *vec, size_t num, size_t len);

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@ -69,6 +69,9 @@ extern struct file_operations random_fops, urandom_fops;
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);
#endif /* __KERNEL___ */
#endif /* _LINUX_RANDOM_H */

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@ -12,7 +12,7 @@ lib-$(CONFIG_SMP) += cpumask.o
lib-y += kobject.o kref.o kobject_uevent.o klist.o
obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o
obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o random32.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG

142
lib/random32.c Normal file
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@ -0,0 +1,142 @@
/*
This is a maximally equidistributed combined Tausworthe generator
based on code from GNU Scientific Library 1.5 (30 Jun 2004)
x_n = (s1_n ^ s2_n ^ s3_n)
s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19))
s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25))
s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11))
The period of this generator is about 2^88.
From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe
Generators", Mathematics of Computation, 65, 213 (1996), 203--213.
This is available on the net from L'Ecuyer's home page,
http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps
There is an erratum in the paper "Tables of Maximally
Equidistributed Combined LFSR Generators", Mathematics of
Computation, 68, 225 (1999), 261--269:
http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
... the k_j most significant bits of z_j must be non-
zero, for each j. (Note: this restriction also applies to the
computer code given in [4], but was mistakenly not mentioned in
that paper.)
This affects the seeding procedure by imposing the requirement
s1 > 1, s2 > 7, s3 > 15.
*/
#include <linux/types.h>
#include <linux/percpu.h>
#include <linux/module.h>
#include <linux/random.h>
struct rnd_state {
u32 s1, s2, s3;
};
static DEFINE_PER_CPU(struct rnd_state, net_rand_state);
static u32 __random32(struct rnd_state *state)
{
#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
return (state->s1 ^ state->s2 ^ state->s3);
}
static void __set_random32(struct rnd_state *state, unsigned long s)
{
if (s == 0)
s = 1; /* default seed is 1 */
#define LCG(n) (69069 * n)
state->s1 = LCG(s);
state->s2 = LCG(state->s1);
state->s3 = LCG(state->s2);
/* "warm it up" */
__random32(state);
__random32(state);
__random32(state);
__random32(state);
__random32(state);
__random32(state);
}
/**
* random32 - pseudo random number generator
*
* A 32 bit pseudo-random number is generated using a fast
* algorithm suitable for simulation. This algorithm is NOT
* considered safe for cryptographic use.
*/
u32 random32(void)
{
unsigned long r;
struct rnd_state *state = &get_cpu_var(net_rand_state);
r = __random32(state);
put_cpu_var(state);
return r;
}
EXPORT_SYMBOL(random32);
/**
* srandom32 - add entropy to pseudo random number generator
* @seed: seed value
*
* Add some additional seeding to the random32() pool.
* Note: this pool is per cpu so it only affects current CPU.
*/
void srandom32(u32 entropy)
{
struct rnd_state *state = &get_cpu_var(net_rand_state);
__set_random32(state, state->s1 ^ entropy);
put_cpu_var(state);
}
EXPORT_SYMBOL(srandom32);
/*
* Generate some initially weak seeding values to allow
* to start the random32() engine.
*/
static int __init random32_init(void)
{
int i;
for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state,i);
__set_random32(state, i + jiffies);
}
return 0;
}
core_initcall(random32_init);
/*
* Generate better values after random number generator
* is fully initalized.
*/
static int __init random32_reseed(void)
{
int i;
unsigned long seed;
for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state,i);
get_random_bytes(&seed, sizeof(seed));
__set_random32(state, seed);
}
return 0;
}
late_initcall(random32_reseed);

View File

@ -3502,8 +3502,6 @@ static int __init net_dev_init(void)
BUG_ON(!dev_boot_phase);
net_random_init();
if (dev_proc_init())
goto out;

View File

@ -30,119 +30,6 @@
#include <asm/system.h>
#include <asm/uaccess.h>
/*
This is a maximally equidistributed combined Tausworthe generator
based on code from GNU Scientific Library 1.5 (30 Jun 2004)
x_n = (s1_n ^ s2_n ^ s3_n)
s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19))
s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25))
s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11))
The period of this generator is about 2^88.
From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe
Generators", Mathematics of Computation, 65, 213 (1996), 203--213.
This is available on the net from L'Ecuyer's home page,
http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps
There is an erratum in the paper "Tables of Maximally
Equidistributed Combined LFSR Generators", Mathematics of
Computation, 68, 225 (1999), 261--269:
http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
... the k_j most significant bits of z_j must be non-
zero, for each j. (Note: this restriction also applies to the
computer code given in [4], but was mistakenly not mentioned in
that paper.)
This affects the seeding procedure by imposing the requirement
s1 > 1, s2 > 7, s3 > 15.
*/
struct nrnd_state {
u32 s1, s2, s3;
};
static DEFINE_PER_CPU(struct nrnd_state, net_rand_state);
static u32 __net_random(struct nrnd_state *state)
{
#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
return (state->s1 ^ state->s2 ^ state->s3);
}
static void __net_srandom(struct nrnd_state *state, unsigned long s)
{
if (s == 0)
s = 1; /* default seed is 1 */
#define LCG(n) (69069 * n)
state->s1 = LCG(s);
state->s2 = LCG(state->s1);
state->s3 = LCG(state->s2);
/* "warm it up" */
__net_random(state);
__net_random(state);
__net_random(state);
__net_random(state);
__net_random(state);
__net_random(state);
}
unsigned long net_random(void)
{
unsigned long r;
struct nrnd_state *state = &get_cpu_var(net_rand_state);
r = __net_random(state);
put_cpu_var(state);
return r;
}
void net_srandom(unsigned long entropy)
{
struct nrnd_state *state = &get_cpu_var(net_rand_state);
__net_srandom(state, state->s1^entropy);
put_cpu_var(state);
}
void __init net_random_init(void)
{
int i;
for_each_possible_cpu(i) {
struct nrnd_state *state = &per_cpu(net_rand_state,i);
__net_srandom(state, i+jiffies);
}
}
static int net_random_reseed(void)
{
int i;
unsigned long seed;
for_each_possible_cpu(i) {
struct nrnd_state *state = &per_cpu(net_rand_state,i);
get_random_bytes(&seed, sizeof(seed));
__net_srandom(state, seed);
}
return 0;
}
late_initcall(net_random_reseed);
int net_msg_cost = 5*HZ;
int net_msg_burst = 10;
@ -153,10 +40,7 @@ int net_ratelimit(void)
{
return __printk_ratelimit(net_msg_cost, net_msg_burst);
}
EXPORT_SYMBOL(net_random);
EXPORT_SYMBOL(net_ratelimit);
EXPORT_SYMBOL(net_srandom);
/*
* Convert an ASCII string to binary IP.