1 d7094239 2003-11-23 devnull #include <u.h>
  2 d7094239 2003-11-23 devnull #include <libc.h>
  3 d7094239 2003-11-23 devnull #include <ip.h>
  4 d7094239 2003-11-23 devnull 
  5 d7094239 2003-11-23 devnull /*
  6 d7094239 2003-11-23 devnull  *  well known IP addresses
  7 d7094239 2003-11-23 devnull  */
  8 d7094239 2003-11-23 devnull uchar IPv4bcast[IPaddrlen] = {
  9 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 10 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 11 d7094239 2003-11-23 devnull 	0, 0, 0xff, 0xff,
 12 d7094239 2003-11-23 devnull 	0xff, 0xff, 0xff, 0xff
 13 d7094239 2003-11-23 devnull };
 14 d7094239 2003-11-23 devnull uchar IPv4allsys[IPaddrlen] = {
 15 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 16 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 17 d7094239 2003-11-23 devnull 	0, 0, 0xff, 0xff,
 18 d7094239 2003-11-23 devnull 	0xe0, 0, 0, 0x01
 19 d7094239 2003-11-23 devnull };
 20 d7094239 2003-11-23 devnull uchar IPv4allrouter[IPaddrlen] = {
 21 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 22 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 23 d7094239 2003-11-23 devnull 	0, 0, 0xff, 0xff,
 24 d7094239 2003-11-23 devnull 	0xe0, 0, 0, 0x02
 25 d7094239 2003-11-23 devnull };
 26 d7094239 2003-11-23 devnull uchar IPallbits[IPaddrlen] = {
 27 d7094239 2003-11-23 devnull 	0xff, 0xff, 0xff, 0xff,
 28 d7094239 2003-11-23 devnull 	0xff, 0xff, 0xff, 0xff,
 29 d7094239 2003-11-23 devnull 	0xff, 0xff, 0xff, 0xff,
 30 d7094239 2003-11-23 devnull 	0xff, 0xff, 0xff, 0xff
 31 d7094239 2003-11-23 devnull };
 32 d7094239 2003-11-23 devnull uchar IPnoaddr[IPaddrlen];
 33 d7094239 2003-11-23 devnull 
 34 d7094239 2003-11-23 devnull /*
 35 d7094239 2003-11-23 devnull  *  prefix of all v4 addresses
 36 d7094239 2003-11-23 devnull  */
 37 d7094239 2003-11-23 devnull uchar v4prefix[IPaddrlen] = {
 38 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 39 d7094239 2003-11-23 devnull 	0, 0, 0, 0,
 40 d7094239 2003-11-23 devnull 	0, 0, 0xff, 0xff,
 41 d7094239 2003-11-23 devnull 	0, 0, 0, 0
 42 d7094239 2003-11-23 devnull };
 43 d7094239 2003-11-23 devnull 
 44 d7094239 2003-11-23 devnull int
 45 d7094239 2003-11-23 devnull isv4(uchar *ip)
 46 d7094239 2003-11-23 devnull {
 47 d7094239 2003-11-23 devnull 	return memcmp(ip, v4prefix, IPv4off) == 0;
 48 d7094239 2003-11-23 devnull }
 49 d7094239 2003-11-23 devnull 
 50 d7094239 2003-11-23 devnull /*
 51 d7094239 2003-11-23 devnull  *  the following routines are unrolled with no memset's to speed
 52 d7094239 2003-11-23 devnull  *  up the usual case
 53 d7094239 2003-11-23 devnull  */
 54 d7094239 2003-11-23 devnull void
 55 d7094239 2003-11-23 devnull v4tov6(uchar *v6, uchar *v4)
 56 d7094239 2003-11-23 devnull {
 57 d7094239 2003-11-23 devnull 	v6[0] = 0;
 58 d7094239 2003-11-23 devnull 	v6[1] = 0;
 59 d7094239 2003-11-23 devnull 	v6[2] = 0;
 60 d7094239 2003-11-23 devnull 	v6[3] = 0;
 61 d7094239 2003-11-23 devnull 	v6[4] = 0;
 62 d7094239 2003-11-23 devnull 	v6[5] = 0;
 63 d7094239 2003-11-23 devnull 	v6[6] = 0;
 64 d7094239 2003-11-23 devnull 	v6[7] = 0;
 65 d7094239 2003-11-23 devnull 	v6[8] = 0;
 66 d7094239 2003-11-23 devnull 	v6[9] = 0;
 67 d7094239 2003-11-23 devnull 	v6[10] = 0xff;
 68 d7094239 2003-11-23 devnull 	v6[11] = 0xff;
 69 d7094239 2003-11-23 devnull 	v6[12] = v4[0];
 70 d7094239 2003-11-23 devnull 	v6[13] = v4[1];
 71 d7094239 2003-11-23 devnull 	v6[14] = v4[2];
 72 d7094239 2003-11-23 devnull 	v6[15] = v4[3];
 73 d7094239 2003-11-23 devnull }
 74 d7094239 2003-11-23 devnull 
 75 d7094239 2003-11-23 devnull int
 76 d7094239 2003-11-23 devnull v6tov4(uchar *v4, uchar *v6)
 77 d7094239 2003-11-23 devnull {
 78 d7094239 2003-11-23 devnull 	if(v6[0] == 0
 79 d7094239 2003-11-23 devnull 	&& v6[1] == 0
 80 d7094239 2003-11-23 devnull 	&& v6[2] == 0
 81 d7094239 2003-11-23 devnull 	&& v6[3] == 0
 82 d7094239 2003-11-23 devnull 	&& v6[4] == 0
 83 d7094239 2003-11-23 devnull 	&& v6[5] == 0
 84 d7094239 2003-11-23 devnull 	&& v6[6] == 0
 85 d7094239 2003-11-23 devnull 	&& v6[7] == 0
 86 d7094239 2003-11-23 devnull 	&& v6[8] == 0
 87 d7094239 2003-11-23 devnull 	&& v6[9] == 0
 88 d7094239 2003-11-23 devnull 	&& v6[10] == 0xff
 89 d7094239 2003-11-23 devnull 	&& v6[11] == 0xff)
 90 d7094239 2003-11-23 devnull 	{
 91 d7094239 2003-11-23 devnull 		v4[0] = v6[12];
 92 d7094239 2003-11-23 devnull 		v4[1] = v6[13];
 93 d7094239 2003-11-23 devnull 		v4[2] = v6[14];
 94 d7094239 2003-11-23 devnull 		v4[3] = v6[15];
 95 d7094239 2003-11-23 devnull 		return 0;
 96 d7094239 2003-11-23 devnull 	} else {
 97 d7094239 2003-11-23 devnull 		memset(v4, 0, 4);
 98 d7094239 2003-11-23 devnull 		if(memcmp(v6, IPnoaddr, IPaddrlen) == 0)
 99 d7094239 2003-11-23 devnull 			return 0;
100 d7094239 2003-11-23 devnull 		return -1;
101 d7094239 2003-11-23 devnull 	}
102 d7094239 2003-11-23 devnull }