+/*
+ * ip_check_options - check that any IP-related options are OK,
+ * and assign appropriate defaults.
+ */
+static void
+ip_check_options()
+{
+ struct hostent *hp;
+ u_int32_t local;
+ ipcp_options *wo = &ipcp_wantoptions[0];
+
+ /*
+ * Default our local IP address based on our hostname.
+ * If local IP address already given, don't bother.
+ */
+ if (wo->ouraddr == 0 && !disable_defaultip) {
+ /*
+ * Look up our hostname (possibly with domain name appended)
+ * and take the first IP address as our local IP address.
+ * If there isn't an IP address for our hostname, too bad.
+ */
+ wo->accept_local = 1; /* don't insist on this default value */
+ if ((hp = gethostbyname(hostname)) != NULL) {
+ local = *(u_int32_t *)hp->h_addr;
+ if (local != 0 && !bad_ip_adrs(local))
+ wo->ouraddr = local;
+ }
+ }
+
+ if (demand && wo->hisaddr == 0) {
+ option_error("remote IP address required for demand-dialling\n");
+ exit(1);
+ }
+#if 0
+ if (demand && wo->accept_remote) {
+ option_error("ipcp-accept-remote is incompatible with demand\n");
+ exit(1);
+ }
+#endif
+}
+
+
+/*
+ * ip_demand_conf - configure the interface as though
+ * IPCP were up, for use with dial-on-demand.
+ */
+static int
+ip_demand_conf(u)
+ int u;
+{
+ ipcp_options *wo = &ipcp_wantoptions[u];
+
+ if (!sifaddr(u, wo->ouraddr, wo->hisaddr, GetMask(wo->ouraddr)))
+ return 0;
+ if (!sifup(u))
+ return 0;
+ if (!sifnpmode(u, PPP_IP, NPMODE_QUEUE))
+ return 0;
+ if (wo->default_route)
+ if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr))
+ default_route_set[u] = 1;
+ if (wo->proxy_arp)
+ if (sifproxyarp(u, wo->hisaddr))
+ proxy_arp_set[u] = 1;
+
+ syslog(LOG_NOTICE, "local IP address %s", ip_ntoa(wo->ouraddr));
+ syslog(LOG_NOTICE, "remote IP address %s", ip_ntoa(wo->hisaddr));
+
+ return 1;
+}
+
+