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/*
* BIRD Library -- IPv4 Address Manipulation Functions
*
* (c) 1998 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include <stdlib.h>
#include "nest/bird.h"
#include "lib/ip.h"
#include "lib/string.h"
int
ipv4_classify(u32 a)
{
u32 b = a >> 24U;
if (b && b <= 0xdf)
{
if (b == 0x7f)
return IADDR_HOST | SCOPE_HOST;
else if (b == 0x0a ||
(a & 0xffff0000) == 0xc0a80000 ||
(a & 0xfff00000) == 0xac100000)
return IADDR_HOST | SCOPE_SITE;
else
return IADDR_HOST | SCOPE_UNIVERSE;
}
if (b >= 0xe0 && b <= 0xef)
return IADDR_MULTICAST | SCOPE_UNIVERSE;
if (a == 0xffffffff)
return IADDR_BROADCAST | SCOPE_LINK;
return IADDR_INVALID;
}
char *
ip_ntop(ip_addr a, char *b)
{
u32 x = _I(a);
return b + bsprintf(b, "%d.%d.%d.%d",
((x >> 24) & 0xff),
((x >> 16) & 0xff),
((x >> 8) & 0xff),
(x & 0xff));
}
char *
ip_ntox(ip_addr a, char *b)
{
return b + bsprintf(b, "%08x", _I(a));
}
u32
ipv4_class_mask(u32 a)
{
u32 m;
if (a < 0x80000000)
m = 0xff000000;
else if (a < 0xc0000000)
m = 0xffff0000;
else
m = 0xffffff00;
while (a & ~m)
m |= m >> 1;
return m;
}
int
ip_pton(char *a, ip_addr *o)
{
int i;
unsigned long int l;
u32 ia = 0;
i=4;
while (i--)
{
char *d, *c = strchr(a, '.');
if (!c != !i)
return 0;
l = strtoul(a, &d, 10);
if (d != c && *d || l > 255)
return 0;
ia = (ia << 8) | l;
if (c)
c++;
a = c;
}
*o = ipa_from_u32(ia);
return 1;
}
byte *
ipv4_skip_header(byte *pkt, int *len)
{
int l = *len;
int q;
if (l < 20 || (*pkt & 0xf0) != 0x40)
return NULL;
q = (*pkt & 0x0f) * 4;
if (q > l)
return NULL;
*len -= q;
return pkt + q;
}
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