2 * Copyright 1994, 1995 Massachusetts Institute of Technology
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5 * its documentation for any purpose and without fee is hereby
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30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/sysctl.h>
37 #include <sys/socket.h>
41 #include <net/if_var.h>
42 #include <net/route.h>
43 #include <net/route_var.h>
46 #include <netinet/in.h>
47 #include <netinet/in_var.h>
48 #include <netinet/ip.h>
49 #include <netinet/ip_icmp.h>
50 #include <netinet/ip_var.h>
52 extern int in_inithead(void **head, int off);
54 extern int in_detachhead(void **head, int off);
58 * Do what we need to do when inserting a route.
60 static struct radix_node *
61 in_addroute(void *v_arg, void *n_arg, struct radix_head *head,
62 struct radix_node *treenodes)
64 struct rtentry *rt = (struct rtentry *)treenodes;
65 struct sockaddr_in *sin = (struct sockaddr_in *)rt_key(rt);
68 * A little bit of help for both IP output and input:
69 * For host routes, we make sure that RTF_BROADCAST
70 * is set for anything that looks like a broadcast address.
71 * This way, we can avoid an expensive call to in_broadcast()
72 * in ip_output() most of the time (because the route passed
73 * to ip_output() is almost always a host route).
75 * We also do the same for local addresses, with the thought
76 * that this might one day be used to speed up ip_input().
78 * We also mark routes to multicast addresses as such, because
79 * it's easy to do and might be useful (but this is much more
80 * dubious since it's so easy to inspect the address).
82 if (rt->rt_flags & RTF_HOST) {
83 if (in_broadcast(sin->sin_addr, rt->rt_ifp)) {
84 rt->rt_flags |= RTF_BROADCAST;
85 } else if (satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr ==
86 sin->sin_addr.s_addr) {
87 rt->rt_flags |= RTF_LOCAL;
90 if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
91 rt->rt_flags |= RTF_MULTICAST;
93 if (rt->rt_ifp != NULL) {
97 * inherit interface MTU if not set or
98 * check if MTU is too large.
100 if (rt->rt_mtu == 0) {
101 rt->rt_mtu = rt->rt_ifp->if_mtu;
102 } else if (rt->rt_mtu > rt->rt_ifp->if_mtu)
103 rt->rt_mtu = rt->rt_ifp->if_mtu;
106 return (rn_addroute(v_arg, n_arg, head, treenodes));
109 static int _in_rt_was_here;
111 * Initialize our routing tree.
114 in_inithead(void **head, int off)
118 rh = rt_table_init(32);
122 rh->rnh_addaddr = in_addroute;
125 if (_in_rt_was_here == 0 ) {
133 in_detachhead(void **head, int off)
136 rt_table_destroy((struct rib_head *)(*head));
142 * This zaps old routes when the interface goes down or interface
143 * address is deleted. In the latter case, it deletes static routes
144 * that point to this address. If we don't do this, we may end up
145 * using the old address in the future. The ones we always want to
146 * get rid of are things like ARP entries, since the user might down
147 * the interface, walk over to a completely different network, and
150 struct in_ifadown_arg {
156 in_ifadownkill(const struct rtentry *rt, void *xap)
158 struct in_ifadown_arg *ap = xap;
160 if (rt->rt_ifa != ap->ifa)
163 if ((rt->rt_flags & RTF_STATIC) != 0 && ap->del == 0)
170 in_ifadown(struct ifaddr *ifa, int delete)
172 struct in_ifadown_arg arg;
174 KASSERT(ifa->ifa_addr->sa_family == AF_INET,
175 ("%s: wrong family", __func__));
180 rt_foreach_fib_walk_del(AF_INET, in_ifadownkill, &arg);
181 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */
185 * inet versions of rt functions. These have fib extensions and
186 * for now will just reference the _fib variants.
187 * eventually this order will be reversed,
190 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum)
192 rtalloc_ign_fib(ro, ignflags, fibnum);
196 in_rtredirect(struct sockaddr *dst,
197 struct sockaddr *gateway,
198 struct sockaddr *netmask,
200 struct sockaddr *src,
203 rtredirect_fib(dst, gateway, netmask, flags, src, fibnum);