1 #include <u.h>
2 #include <libc.h>
3 #include <ip.h>
4
5 static uchar classmask[4][16] = {
6 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0x00,0x00,0x00,
7 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0x00,0x00,0x00,
8 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0x00,0x00,
9 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0x00,
10 };
11
12 static uchar v6loopback[IPaddrlen] = {
13 0, 0, 0, 0,
14 0, 0, 0, 0,
15 0, 0, 0, 0,
16 0, 0, 0, 0x01
17 };
18
19 static uchar v6linklocal[IPaddrlen] = {
20 0xfe, 0x80, 0, 0,
21 0, 0, 0, 0,
22 0, 0, 0, 0,
23 0, 0, 0, 0
24 };
25 static uchar v6linklocalmask[IPaddrlen] = {
26 0xff, 0xff, 0xff, 0xff,
27 0xff, 0xff, 0xff, 0xff,
28 0, 0, 0, 0,
29 0, 0, 0, 0
30 };
31 static int v6llpreflen = 8; /* link-local prefix length in bytes */
32
33 static uchar v6multicast[IPaddrlen] = {
34 0xff, 0, 0, 0,
35 0, 0, 0, 0,
36 0, 0, 0, 0,
37 0, 0, 0, 0
38 };
39 static uchar v6multicastmask[IPaddrlen] = {
40 0xff, 0, 0, 0,
41 0, 0, 0, 0,
42 0, 0, 0, 0,
43 0, 0, 0, 0
44 };
45 static int v6mcpreflen = 1; /* multicast prefix length */
46
47 static uchar v6solicitednode[IPaddrlen] = {
48 0xff, 0x02, 0, 0,
49 0, 0, 0, 0,
50 0, 0, 0, 0x01,
51 0xff, 0, 0, 0
52 };
53 static uchar v6solicitednodemask[IPaddrlen] = {
54 0xff, 0xff, 0xff, 0xff,
55 0xff, 0xff, 0xff, 0xff,
56 0xff, 0xff, 0xff, 0xff,
57 0xff, 0x0, 0x0, 0x0
58 };
59 static int v6snpreflen = 13;
60
61 uchar*
defmask(uchar * ip)62 defmask(uchar *ip)
63 {
64 if(isv4(ip))
65 return classmask[ip[IPv4off]>>6];
66 else {
67 if(ipcmp(ip, v6loopback) == 0)
68 return IPallbits;
69 else if(memcmp(ip, v6linklocal, v6llpreflen) == 0)
70 return v6linklocalmask;
71 else if(memcmp(ip, v6solicitednode, v6snpreflen) == 0)
72 return v6solicitednodemask;
73 else if(memcmp(ip, v6multicast, v6mcpreflen) == 0)
74 return v6multicastmask;
75 return IPallbits;
76 }
77 }
78
79 void
maskip(uchar * from,uchar * mask,uchar * to)80 maskip(uchar *from, uchar *mask, uchar *to)
81 {
82 int i;
83
84 for(i = 0; i < IPaddrlen; i++)
85 to[i] = from[i] & mask[i];
86 }
87