407 lines
8.7 KiB
C
407 lines
8.7 KiB
C
/*
|
|
* Generic address resultion entity
|
|
*
|
|
* Authors:
|
|
* net_random Alan Cox
|
|
* net_ratelimit Andi Kleen
|
|
* in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
|
|
*
|
|
* Created by Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/inet.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/net.h>
|
|
#include <linux/string.h>
|
|
#include <linux/types.h>
|
|
#include <linux/random.h>
|
|
#include <linux/percpu.h>
|
|
#include <linux/init.h>
|
|
|
|
#include <asm/byteorder.h>
|
|
#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;
|
|
|
|
/*
|
|
* All net warning printk()s should be guarded by this function.
|
|
*/
|
|
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.
|
|
* This is outside of net/ipv4/ because various code that uses IP addresses
|
|
* is otherwise not dependent on the TCP/IP stack.
|
|
*/
|
|
|
|
__be32 in_aton(const char *str)
|
|
{
|
|
unsigned long l;
|
|
unsigned int val;
|
|
int i;
|
|
|
|
l = 0;
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
l <<= 8;
|
|
if (*str != '\0')
|
|
{
|
|
val = 0;
|
|
while (*str != '\0' && *str != '.' && *str != '\n')
|
|
{
|
|
val *= 10;
|
|
val += *str - '0';
|
|
str++;
|
|
}
|
|
l |= val;
|
|
if (*str != '\0')
|
|
str++;
|
|
}
|
|
}
|
|
return(htonl(l));
|
|
}
|
|
|
|
EXPORT_SYMBOL(in_aton);
|
|
|
|
#define IN6PTON_XDIGIT 0x00010000
|
|
#define IN6PTON_DIGIT 0x00020000
|
|
#define IN6PTON_COLON_MASK 0x00700000
|
|
#define IN6PTON_COLON_1 0x00100000 /* single : requested */
|
|
#define IN6PTON_COLON_2 0x00200000 /* second : requested */
|
|
#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
|
|
#define IN6PTON_DOT 0x00800000 /* . */
|
|
#define IN6PTON_DELIM 0x10000000
|
|
#define IN6PTON_NULL 0x20000000 /* first/tail */
|
|
#define IN6PTON_UNKNOWN 0x40000000
|
|
|
|
static inline int digit2bin(char c, char delim)
|
|
{
|
|
if (c == delim || c == '\0')
|
|
return IN6PTON_DELIM;
|
|
if (c == '.')
|
|
return IN6PTON_DOT;
|
|
if (c >= '0' && c <= '9')
|
|
return (IN6PTON_DIGIT | (c - '0'));
|
|
return IN6PTON_UNKNOWN;
|
|
}
|
|
|
|
static inline int xdigit2bin(char c, char delim)
|
|
{
|
|
if (c == delim || c == '\0')
|
|
return IN6PTON_DELIM;
|
|
if (c == ':')
|
|
return IN6PTON_COLON_MASK;
|
|
if (c == '.')
|
|
return IN6PTON_DOT;
|
|
if (c >= '0' && c <= '9')
|
|
return (IN6PTON_XDIGIT | IN6PTON_DIGIT| (c - '0'));
|
|
if (c >= 'a' && c <= 'f')
|
|
return (IN6PTON_XDIGIT | (c - 'a' + 10));
|
|
if (c >= 'A' && c <= 'F')
|
|
return (IN6PTON_XDIGIT | (c - 'A' + 10));
|
|
return IN6PTON_UNKNOWN;
|
|
}
|
|
|
|
int in4_pton(const char *src, int srclen,
|
|
u8 *dst,
|
|
char delim, const char **end)
|
|
{
|
|
const char *s;
|
|
u8 *d;
|
|
u8 dbuf[4];
|
|
int ret = 0;
|
|
int i;
|
|
int w = 0;
|
|
|
|
if (srclen < 0)
|
|
srclen = strlen(src);
|
|
s = src;
|
|
d = dbuf;
|
|
i = 0;
|
|
while(1) {
|
|
int c;
|
|
c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
|
|
if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM))) {
|
|
goto out;
|
|
}
|
|
if (c & (IN6PTON_DOT | IN6PTON_DELIM)) {
|
|
if (w == 0)
|
|
goto out;
|
|
*d++ = w & 0xff;
|
|
w = 0;
|
|
i++;
|
|
if (c & IN6PTON_DELIM) {
|
|
if (i != 4)
|
|
goto out;
|
|
break;
|
|
}
|
|
goto cont;
|
|
}
|
|
w = (w * 10) + c;
|
|
if ((w & 0xffff) > 255) {
|
|
goto out;
|
|
}
|
|
cont:
|
|
if (i >= 4)
|
|
goto out;
|
|
s++;
|
|
srclen--;
|
|
}
|
|
ret = 1;
|
|
memcpy(dst, dbuf, sizeof(dbuf));
|
|
out:
|
|
if (end)
|
|
*end = s;
|
|
return ret;
|
|
}
|
|
|
|
EXPORT_SYMBOL(in4_pton);
|
|
|
|
int in6_pton(const char *src, int srclen,
|
|
u8 *dst,
|
|
char delim, const char **end)
|
|
{
|
|
const char *s, *tok = NULL;
|
|
u8 *d, *dc = NULL;
|
|
u8 dbuf[16];
|
|
int ret = 0;
|
|
int i;
|
|
int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
|
|
int w = 0;
|
|
|
|
memset(dbuf, 0, sizeof(dbuf));
|
|
|
|
s = src;
|
|
d = dbuf;
|
|
if (srclen < 0)
|
|
srclen = strlen(src);
|
|
|
|
while (1) {
|
|
int c;
|
|
|
|
c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
|
|
if (!(c & state))
|
|
goto out;
|
|
if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
|
|
/* process one 16-bit word */
|
|
if (!(state & IN6PTON_NULL)) {
|
|
*d++ = (w >> 8) & 0xff;
|
|
*d++ = w & 0xff;
|
|
}
|
|
w = 0;
|
|
if (c & IN6PTON_DELIM) {
|
|
/* We've processed last word */
|
|
break;
|
|
}
|
|
/*
|
|
* COLON_1 => XDIGIT
|
|
* COLON_2 => XDIGIT|DELIM
|
|
* COLON_1_2 => COLON_2
|
|
*/
|
|
switch (state & IN6PTON_COLON_MASK) {
|
|
case IN6PTON_COLON_2:
|
|
dc = d;
|
|
state = IN6PTON_XDIGIT | IN6PTON_DELIM;
|
|
if (dc - dbuf >= sizeof(dbuf))
|
|
state |= IN6PTON_NULL;
|
|
break;
|
|
case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
|
|
state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
|
|
break;
|
|
case IN6PTON_COLON_1:
|
|
state = IN6PTON_XDIGIT;
|
|
break;
|
|
case IN6PTON_COLON_1_2:
|
|
state = IN6PTON_COLON_2;
|
|
break;
|
|
default:
|
|
state = 0;
|
|
}
|
|
tok = s + 1;
|
|
goto cont;
|
|
}
|
|
|
|
if (c & IN6PTON_DOT) {
|
|
ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
|
|
if (ret > 0) {
|
|
d += 4;
|
|
break;
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
w = (w << 4) | (0xff & c);
|
|
state = IN6PTON_COLON_1 | IN6PTON_DELIM;
|
|
if (!(w & 0xf000)) {
|
|
state |= IN6PTON_XDIGIT;
|
|
}
|
|
if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
|
|
state |= IN6PTON_COLON_1_2;
|
|
state &= ~IN6PTON_DELIM;
|
|
}
|
|
if (d + 2 >= dbuf + sizeof(dbuf)) {
|
|
state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
|
|
}
|
|
cont:
|
|
if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
|
|
d + 4 == dbuf + sizeof(dbuf)) {
|
|
state |= IN6PTON_DOT;
|
|
}
|
|
if (d >= dbuf + sizeof(dbuf)) {
|
|
state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
|
|
}
|
|
s++;
|
|
srclen--;
|
|
}
|
|
|
|
i = 15; d--;
|
|
|
|
if (dc) {
|
|
while(d >= dc)
|
|
dst[i--] = *d--;
|
|
while(i >= dc - dbuf)
|
|
dst[i--] = 0;
|
|
while(i >= 0)
|
|
dst[i--] = *d--;
|
|
} else
|
|
memcpy(dst, dbuf, sizeof(dbuf));
|
|
|
|
ret = 1;
|
|
out:
|
|
if (end)
|
|
*end = s;
|
|
return ret;
|
|
}
|
|
|
|
EXPORT_SYMBOL(in6_pton);
|