/* * Copyright (c) 1983 Regents of the University of California. * All rights reserved. The Berkeley software License Agreement * specifies the terms and conditions for redistribution. */ #ifndef lint static char sccsid[] = "@(#)inet.c 5.1 (Berkeley) 06/04/85"; #endif not lint /* * Temporarily, copy these routines from the kernel, * as we need to know about subnets. */ #include "defs.h" extern struct interface *ifnet; /* * Formulate an Internet address from network + host. */ struct in_addr inet_makeaddr(net, host) u_long net, host; { register struct interface *ifp; register u_long mask; u_long addr; if (IN_CLASSA(net)) mask = IN_CLASSA_HOST; else if (IN_CLASSB(net)) mask = IN_CLASSB_HOST; else mask = IN_CLASSC_HOST; for (ifp = ifnet; ifp; ifp = ifp->int_next) if ((ifp->int_netmask & net) == ifp->int_net) { mask = ~ifp->int_subnetmask; break; } addr = net | (host & mask); addr = htonl(addr); return (*(struct in_addr *)&addr); } /* * Return the network number from an internet address. */ inet_netof(in) struct in_addr in; { register u_long i = ntohl(in.s_addr); register u_long net; register struct interface *ifp; if (IN_CLASSA(i)) net = i & IN_CLASSA_NET; else if (IN_CLASSB(i)) net = i & IN_CLASSB_NET; else net = i & IN_CLASSC_NET; /* * Check whether network is a subnet; * if so, return subnet number. */ for (ifp = ifnet; ifp; ifp = ifp->int_next) if ((ifp->int_netmask & net) == ifp->int_net) return (i & ifp->int_subnetmask); return (net); } /* * Return the host portion of an internet address. */ inet_lnaof(in) struct in_addr in; { register u_long i = ntohl(in.s_addr); register u_long net, host; register struct interface *ifp; if (IN_CLASSA(i)) { net = i & IN_CLASSA_NET; host = i & IN_CLASSA_HOST; } else if (IN_CLASSB(i)) { net = i & IN_CLASSB_NET; host = i & IN_CLASSB_HOST; } else { net = i & IN_CLASSC_NET; host = i & IN_CLASSC_HOST; } /* * Check whether network is a subnet; * if so, use the modified interpretation of `host'. */ for (ifp = ifnet; ifp; ifp = ifp->int_next) if ((ifp->int_netmask & net) == ifp->int_net) return (host &~ ifp->int_subnetmask); return (host); }