/* * BIRD Library -- IPv4 Address Manipulation Functions * * (c) 1998 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #include <stdlib.h> #include "nest/bird.h" #include "lib/ip.h" #include "lib/string.h" int ipv4_classify(u32 a) { u32 b = a >> 24U; if (b && b <= 0xdf) { if (b == 0x7f) return IADDR_HOST | SCOPE_HOST; else if (b == 0x0a || (a & 0xffff0000) == 0xc0a80000 || (a & 0xfff00000) == 0xac100000) return IADDR_HOST | SCOPE_SITE; else return IADDR_HOST | SCOPE_UNIVERSE; } if (b >= 0xe0 && b <= 0xef) return IADDR_MULTICAST | SCOPE_UNIVERSE; if (a == 0xffffffff) return IADDR_BROADCAST | SCOPE_LINK; return IADDR_INVALID; } char * ip_ntop(ip_addr a, char *b) { u32 x = _I(a); return b + bsprintf(b, "%d.%d.%d.%d", ((x >> 24) & 0xff), ((x >> 16) & 0xff), ((x >> 8) & 0xff), (x & 0xff)); } char * ip_ntox(ip_addr a, char *b) { return b + bsprintf(b, "%08x", _I(a)); } u32 ipv4_class_mask(u32 a) { u32 m; if (a < 0x80000000) m = 0xff000000; if (a < 0xc0000000) m = 0xffff0000; else m = 0xffffff00; while (a & ~m) m |= m >> 1; return m; } int ip_pton(char *a, ip_addr *o) { int i; unsigned long int l; u32 ia = 0; i=4; while (i--) { char *d, *c = strchr(a, '.'); if (!c != !i) return 0; l = strtoul(a, &d, 10); if (d != c && *d || l > 255) return 0; ia = (ia << 8) | l; if (c) c++; a = c; } *o = ipa_from_u32(ia); return 1; } byte * ipv4_skip_header(byte *pkt, int *len) { int l = *len; int q; if (l < 20 || (*pkt & 0xf0) != 0x40) return NULL; q = (*pkt & 0x0f) * 4; if (q > l) return NULL; *len -= q; return pkt + q; }