| rsc | d709423 | 2003-11-23 18:23:20 +0000 | [diff] [blame] | 1 | #include <u.h> |
| 2 | #include <libc.h> |
| 3 | #include <ip.h> |
| 4 | |
| 5 | /* |
| 6 | * well known IP addresses |
| 7 | */ |
| 8 | uchar IPv4bcast[IPaddrlen] = { |
| 9 | 0, 0, 0, 0, |
| 10 | 0, 0, 0, 0, |
| 11 | 0, 0, 0xff, 0xff, |
| 12 | 0xff, 0xff, 0xff, 0xff |
| 13 | }; |
| 14 | uchar IPv4allsys[IPaddrlen] = { |
| 15 | 0, 0, 0, 0, |
| 16 | 0, 0, 0, 0, |
| 17 | 0, 0, 0xff, 0xff, |
| 18 | 0xe0, 0, 0, 0x01 |
| 19 | }; |
| 20 | uchar IPv4allrouter[IPaddrlen] = { |
| 21 | 0, 0, 0, 0, |
| 22 | 0, 0, 0, 0, |
| 23 | 0, 0, 0xff, 0xff, |
| 24 | 0xe0, 0, 0, 0x02 |
| 25 | }; |
| 26 | uchar IPallbits[IPaddrlen] = { |
| 27 | 0xff, 0xff, 0xff, 0xff, |
| 28 | 0xff, 0xff, 0xff, 0xff, |
| 29 | 0xff, 0xff, 0xff, 0xff, |
| 30 | 0xff, 0xff, 0xff, 0xff |
| 31 | }; |
| 32 | uchar IPnoaddr[IPaddrlen]; |
| 33 | |
| 34 | /* |
| 35 | * prefix of all v4 addresses |
| 36 | */ |
| 37 | uchar v4prefix[IPaddrlen] = { |
| 38 | 0, 0, 0, 0, |
| 39 | 0, 0, 0, 0, |
| 40 | 0, 0, 0xff, 0xff, |
| 41 | 0, 0, 0, 0 |
| 42 | }; |
| 43 | |
| 44 | int |
| 45 | isv4(uchar *ip) |
| 46 | { |
| 47 | return memcmp(ip, v4prefix, IPv4off) == 0; |
| 48 | } |
| 49 | |
| 50 | /* |
| 51 | * the following routines are unrolled with no memset's to speed |
| 52 | * up the usual case |
| 53 | */ |
| 54 | void |
| 55 | v4tov6(uchar *v6, uchar *v4) |
| 56 | { |
| 57 | v6[0] = 0; |
| 58 | v6[1] = 0; |
| 59 | v6[2] = 0; |
| 60 | v6[3] = 0; |
| 61 | v6[4] = 0; |
| 62 | v6[5] = 0; |
| 63 | v6[6] = 0; |
| 64 | v6[7] = 0; |
| 65 | v6[8] = 0; |
| 66 | v6[9] = 0; |
| 67 | v6[10] = 0xff; |
| 68 | v6[11] = 0xff; |
| 69 | v6[12] = v4[0]; |
| 70 | v6[13] = v4[1]; |
| 71 | v6[14] = v4[2]; |
| 72 | v6[15] = v4[3]; |
| 73 | } |
| 74 | |
| 75 | int |
| 76 | v6tov4(uchar *v4, uchar *v6) |
| 77 | { |
| 78 | if(v6[0] == 0 |
| 79 | && v6[1] == 0 |
| 80 | && v6[2] == 0 |
| 81 | && v6[3] == 0 |
| 82 | && v6[4] == 0 |
| 83 | && v6[5] == 0 |
| 84 | && v6[6] == 0 |
| 85 | && v6[7] == 0 |
| 86 | && v6[8] == 0 |
| 87 | && v6[9] == 0 |
| 88 | && v6[10] == 0xff |
| 89 | && v6[11] == 0xff) |
| 90 | { |
| 91 | v4[0] = v6[12]; |
| 92 | v4[1] = v6[13]; |
| 93 | v4[2] = v6[14]; |
| 94 | v4[3] = v6[15]; |
| 95 | return 0; |
| 96 | } else { |
| 97 | memset(v4, 0, 4); |
| 98 | if(memcmp(v6, IPnoaddr, IPaddrlen) == 0) |
| 99 | return 0; |
| 100 | return -1; |
| 101 | } |
| 102 | } |
