conterm/libip/classmask.c

87 lines
1.9 KiB
C

#include <u.h>
#include <libc.h>
#include <ip.h>
static uchar classmask[4][16] = {
0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0x00,0x00,0x00,
0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0x00,0x00,0x00,
0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0x00,0x00,
0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0x00,
};
static uchar v6loopback[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0x01
};
static uchar v6linklocal[IPaddrlen] = {
0xfe, 0x80, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0
};
static uchar v6linklocalmask[IPaddrlen] = {
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0, 0, 0, 0,
0, 0, 0, 0
};
static int v6llpreflen = 8; /* link-local prefix length in bytes */
static uchar v6multicast[IPaddrlen] = {
0xff, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0
};
static uchar v6multicastmask[IPaddrlen] = {
0xff, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0
};
static int v6mcpreflen = 1; /* multicast prefix length */
static uchar v6solicitednode[IPaddrlen] = {
0xff, 0x02, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0x01,
0xff, 0, 0, 0
};
static uchar v6solicitednodemask[IPaddrlen] = {
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0x0, 0x0, 0x0
};
static int v6snpreflen = 13;
uchar*
defmask(uchar *ip)
{
if(isv4(ip))
return classmask[ip[IPv4off]>>6];
else {
if(ipcmp(ip, v6loopback) == 0)
return IPallbits;
else if(memcmp(ip, v6linklocal, v6llpreflen) == 0)
return v6linklocalmask;
else if(memcmp(ip, v6solicitednode, v6snpreflen) == 0)
return v6solicitednodemask;
else if(memcmp(ip, v6multicast, v6mcpreflen) == 0)
return v6multicastmask;
return IPallbits;
}
}
void
maskip(uchar *from, uchar *mask, uchar *to)
{
int i;
for(i = 0; i < IPaddrlen; i++)
to[i] = from[i] & mask[i];
}