2 * Copyright 1994, 1995 Massachusetts Institute of Technology
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
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16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
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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>
45 #include <netinet/in.h>
46 #include <netinet/in_var.h>
47 #include <netinet/ip.h>
48 #include <netinet/ip_icmp.h>
49 #include <netinet/ip_var.h>
51 extern int in_inithead(void **head, int off);
53 extern int in_detachhead(void **head, int off);
57 * Do what we need to do when inserting a route.
59 static struct radix_node *
60 in_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
61 struct radix_node *treenodes)
63 struct rtentry *rt = (struct rtentry *)treenodes;
64 struct sockaddr_in *sin = (struct sockaddr_in *)rt_key(rt);
66 RADIX_NODE_HEAD_WLOCK_ASSERT(head);
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)
116 struct radix_node_head *rnh;
118 if (!rn_inithead(head, 32))
122 RADIX_NODE_HEAD_LOCK_INIT(rnh);
124 rnh->rnh_addaddr = in_addroute;
125 if (_in_rt_was_here == 0 ) {
133 in_detachhead(void **head, int off)
141 * This zaps old routes when the interface goes down or interface
142 * address is deleted. In the latter case, it deletes static routes
143 * that point to this address. If we don't do this, we may end up
144 * using the old address in the future. The ones we always want to
145 * get rid of are things like ARP entries, since the user might down
146 * the interface, walk over to a completely different network, and
149 struct in_ifadown_arg {
150 struct radix_node_head *rnh;
156 in_ifadownkill(struct radix_node *rn, void *xap)
158 struct in_ifadown_arg *ap = xap;
159 struct rtentry *rt = (struct rtentry *)rn;
162 if (rt->rt_ifa == ap->ifa &&
163 (ap->del || !(rt->rt_flags & RTF_STATIC))) {
165 * Aquire a reference so that it can later be freed
166 * as the refcount would be 0 here in case of at least
171 * Disconnect it from the tree and permit protocols
174 rt_expunge(ap->rnh, rt);
176 * At this point it is an rttrash node, and in case
177 * the above is the only reference we must free it.
178 * If we do not noone will have a pointer and the
179 * rtentry will be leaked forever.
180 * In case someone else holds a reference, we are
181 * fine as we only decrement the refcount. In that
182 * case if the other entity calls RT_REMREF, we
183 * will still be leaking but at least we tried.
193 in_ifadown(struct ifaddr *ifa, int delete)
195 struct in_ifadown_arg arg;
196 struct radix_node_head *rnh;
199 KASSERT(ifa->ifa_addr->sa_family == AF_INET,
200 ("%s: wrong family", __func__));
202 for ( fibnum = 0; fibnum < rt_numfibs; fibnum++) {
203 rnh = rt_tables_get_rnh(fibnum, AF_INET);
207 RADIX_NODE_HEAD_LOCK(rnh);
208 rnh->rnh_walktree(rnh, in_ifadownkill, &arg);
209 RADIX_NODE_HEAD_UNLOCK(rnh);
210 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */
215 * inet versions of rt functions. These have fib extensions and
216 * for now will just reference the _fib variants.
217 * eventually this order will be reversed,
220 in_rtalloc_ign(struct route *ro, u_long ignflags, u_int fibnum)
222 rtalloc_ign_fib(ro, ignflags, fibnum);
226 in_rtrequest( int req,
227 struct sockaddr *dst,
228 struct sockaddr *gateway,
229 struct sockaddr *netmask,
231 struct rtentry **ret_nrt,
234 return (rtrequest_fib(req, dst, gateway, netmask,
235 flags, ret_nrt, fibnum));
239 in_rtalloc1(struct sockaddr *dst, int report, u_long ignflags, u_int fibnum)
241 return (rtalloc1_fib(dst, report, ignflags, fibnum));
245 in_rtredirect(struct sockaddr *dst,
246 struct sockaddr *gateway,
247 struct sockaddr *netmask,
249 struct sockaddr *src,
252 rtredirect_fib(dst, gateway, netmask, flags, src, fibnum);
256 in_rtalloc(struct route *ro, u_int fibnum)
258 rtalloc_ign_fib(ro, 0UL, fibnum);
262 int in_rt_getifa(struct rt_addrinfo *, u_int fibnum);
263 int in_rtioctl(u_long, caddr_t, u_int);
264 int in_rtrequest1(int, struct rt_addrinfo *, struct rtentry **, u_int);