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#include <u.h>
#include <libc.h>
#include <ip.h>
/*
* well known IP addresses
*/
uchar IPv4bcast[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff
};
uchar IPv4allsys[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0xe0, 0, 0, 0x01
};
uchar IPv4allrouter[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0xe0, 0, 0, 0x02
};
uchar IPallbits[IPaddrlen] = {
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff
};
uchar IPnoaddr[IPaddrlen];
/*
* prefix of all v4 addresses
*/
uchar v4prefix[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0, 0, 0, 0
};
int
isv4(uchar *ip)
{
return memcmp(ip, v4prefix, IPv4off) == 0;
}
/*
* the following routines are unrolled with no memset's to speed
* up the usual case
*/
void
v4tov6(uchar *v6, uchar *v4)
{
v6[0] = 0;
v6[1] = 0;
v6[2] = 0;
v6[3] = 0;
v6[4] = 0;
v6[5] = 0;
v6[6] = 0;
v6[7] = 0;
v6[8] = 0;
v6[9] = 0;
v6[10] = 0xff;
v6[11] = 0xff;
v6[12] = v4[0];
v6[13] = v4[1];
v6[14] = v4[2];
v6[15] = v4[3];
}
int
v6tov4(uchar *v4, uchar *v6)
{
if(v6[0] == 0
&& v6[1] == 0
&& v6[2] == 0
&& v6[3] == 0
&& v6[4] == 0
&& v6[5] == 0
&& v6[6] == 0
&& v6[7] == 0
&& v6[8] == 0
&& v6[9] == 0
&& v6[10] == 0xff
&& v6[11] == 0xff)
{
v4[0] = v6[12];
v4[1] = v6[13];
v4[2] = v6[14];
v4[3] = v6[15];
return 0;
} else {
memset(v4, 0, 4);
if(memcmp(v6, IPnoaddr, IPaddrlen) == 0)
return 0;
return -1;
}
}
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