mirror of
https://gitlab.nic.cz/labs/bird.git
synced 2024-12-22 01:31:55 +00:00
112 lines
1.8 KiB
C
112 lines
1.8 KiB
C
/*
|
|
* 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 <string.h>
|
|
#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;
|
|
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,j;
|
|
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;
|
|
}
|