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 struct epoch_tracker et;
87 bcast = in_broadcast(sin->sin_addr, rt->rt_ifp);
90 rt->rt_flags |= RTF_BROADCAST;
91 else if (satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr ==
93 rt->rt_flags |= RTF_LOCAL;
95 if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
96 rt->rt_flags |= RTF_MULTICAST;
98 if (rt->rt_ifp != NULL) {
102 * inherit interface MTU if not set or
103 * check if MTU is too large.
105 if (rt->rt_mtu == 0) {
106 rt->rt_mtu = rt->rt_ifp->if_mtu;
107 } else if (rt->rt_mtu > rt->rt_ifp->if_mtu)
108 rt->rt_mtu = rt->rt_ifp->if_mtu;
111 return (rn_addroute(v_arg, n_arg, head, treenodes));
114 static int _in_rt_was_here;
116 * Initialize our routing tree.
119 in_inithead(void **head, int off)
123 rh = rt_table_init(32);
127 rh->rnh_addaddr = in_addroute;
130 if (_in_rt_was_here == 0 ) {
138 in_detachhead(void **head, int off)
141 rt_table_destroy((struct rib_head *)(*head));
147 * This zaps old routes when the interface goes down or interface
148 * address is deleted. In the latter case, it deletes static routes
149 * that point to this address. If we don't do this, we may end up
150 * using the old address in the future. The ones we always want to
151 * get rid of are things like ARP entries, since the user might down
152 * the interface, walk over to a completely different network, and
155 struct in_ifadown_arg {
161 in_ifadownkill(const struct rtentry *rt, void *xap)
163 struct in_ifadown_arg *ap = xap;
165 if (rt->rt_ifa != ap->ifa)
168 if ((rt->rt_flags & RTF_STATIC) != 0 && ap->del == 0)
175 in_ifadown(struct ifaddr *ifa, int delete)
177 struct in_ifadown_arg arg;
179 KASSERT(ifa->ifa_addr->sa_family == AF_INET,
180 ("%s: wrong family", __func__));
185 rt_foreach_fib_walk_del(AF_INET, in_ifadownkill, &arg);
186 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */
190 * inet versions of rt functions. These have fib extensions and
191 * for now will just reference the _fib variants.
192 * eventually this order will be reversed,
195 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum)
197 rtalloc_ign_fib(ro, ignflags, fibnum);
201 in_rtredirect(struct sockaddr *dst,
202 struct sockaddr *gateway,
203 struct sockaddr *netmask,
205 struct sockaddr *src,
208 rtredirect_fib(dst, gateway, netmask, flags, src, fibnum);