diff options
Diffstat (limited to 'src/libip/ipaux.c')
| -rw-r--r-- | src/libip/ipaux.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/src/libip/ipaux.c b/src/libip/ipaux.c new file mode 100644 index 00000000..215b37ee --- /dev/null +++ b/src/libip/ipaux.c @@ -0,0 +1,102 @@ +#include <u.h> +#include <libc.h> +#include <ip.h> + +/* + * well known IP addresses + */ +uchar IPv4bcast[IPaddrlen] = { + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff +}; +uchar IPv4allsys[IPaddrlen] = { + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0xff, 0xff, + 0xe0, 0, 0, 0x01 +}; +uchar IPv4allrouter[IPaddrlen] = { + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0xff, 0xff, + 0xe0, 0, 0, 0x02 +}; +uchar IPallbits[IPaddrlen] = { + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff +}; +uchar IPnoaddr[IPaddrlen]; + +/* + * prefix of all v4 addresses + */ +uchar v4prefix[IPaddrlen] = { + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0xff, 0xff, + 0, 0, 0, 0 +}; + +int +isv4(uchar *ip) +{ + return memcmp(ip, v4prefix, IPv4off) == 0; +} + +/* + * the following routines are unrolled with no memset's to speed + * up the usual case + */ +void +v4tov6(uchar *v6, uchar *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(uchar *v4, uchar *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; + } +} |