jehanne/sys/src/lib/ip/ipaux.c

112 lines
1.9 KiB
C

/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <u.h>
#include <lib9.h>
#include <ip.h>
/*
* well known IP addresses
*/
uint8_t IPv4bcast[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff
};
uint8_t IPv4allsys[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0xe0, 0, 0, 0x01
};
uint8_t IPv4allrouter[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0xe0, 0, 0, 0x02
};
uint8_t IPallbits[IPaddrlen] = {
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff
};
uint8_t IPnoaddr[IPaddrlen];
/*
* prefix of all v4 addresses
*/
uint8_t v4prefix[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
0, 0, 0, 0
};
int
isv4(uint8_t *ip)
{
return memcmp(ip, v4prefix, IPv4off) == 0;
}
/*
* the following routines are unrolled with no memset's to speed
* up the usual case
*/
void
v4tov6(uint8_t *v6, uint8_t *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(uint8_t *v4, uint8_t *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;
}
}