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30 #include <sys/cdefs.h>
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
34 #include <sys/sysctl.h>
35 #include <sys/socket.h>
39 #include <net/if_var.h>
40 #include <net/if_private.h>
41 #include <net/route.h>
42 #include <net/route/route_ctl.h>
43 #include <net/route/route_var.h>
44 #include <net/route/nhop.h>
47 #include <netinet/in.h>
48 #include <netinet/in_var.h>
49 #include <netinet/ip.h>
50 #include <netinet/ip_icmp.h>
51 #include <netinet/ip_var.h>
54 rib4_set_nh_pfxflags(u_int fibnum, const struct sockaddr *addr, const struct sockaddr *mask,
55 struct nhop_object *nh)
57 const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr;
58 const struct sockaddr_in *mask4 = (const struct sockaddr_in *)mask;
59 bool is_broadcast = false;
62 nhop_set_pxtype_flag(nh, NHF_HOST);
64 * Backward compatibility:
65 * if the destination is broadcast,
66 * mark route as broadcast.
67 * This behavior was useful when route cloning
68 * was in place, so there was an explicit cloned
69 * route for every broadcasted address.
70 * Currently (2020-04) there is no kernel machinery
71 * to do route cloning, though someone might explicitly
72 * add these routes to support some cases with active-active
73 * load balancing. Given that, retain this support.
75 if (in_broadcast(addr4->sin_addr, nh->nh_ifp))
77 } else if (mask4->sin_addr.s_addr == 0)
78 nhop_set_pxtype_flag(nh, NHF_DEFAULT);
80 nhop_set_pxtype_flag(nh, 0);
82 nhop_set_broadcast(nh, is_broadcast);
88 rib4_augment_nh(u_int fibnum, struct nhop_object *nh)
92 * inherit interface MTU if not set or
93 * check if MTU is too large.
95 if (nh->nh_mtu == 0) {
96 nh->nh_mtu = nh->nh_ifp->if_mtu;
97 } else if (nh->nh_mtu > nh->nh_ifp->if_mtu)
98 nh->nh_mtu = nh->nh_ifp->if_mtu;
100 /* Set nhop type to basic per-AF nhop */
101 if (nhop_get_type(nh) == 0) {
103 if (nh->nh_flags & NHF_GATEWAY)
104 nh_type = NH_TYPE_IPV4_ETHER_NHOP;
106 nh_type = NH_TYPE_IPV4_ETHER_RSLV;
108 nhop_set_type(nh, nh_type);
115 * Initialize our routing tree.
118 in_inithead(uint32_t fibnum)
122 rh = rt_table_init(32, AF_INET, fibnum);
126 rh->rnh_set_nh_pfxflags = rib4_set_nh_pfxflags;
127 rh->rnh_augment_nh = rib4_augment_nh;
134 in_detachhead(struct rib_head *rh)
137 rt_table_destroy(rh);
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, const struct nhop_object *nh,
159 struct in_ifadown_arg *ap = xap;
161 if (nh->nh_ifa != ap->ifa)
164 if ((nhop_get_rtflags(nh) & RTF_STATIC) != 0 && ap->del == 0)
171 in_ifadown(struct ifaddr *ifa, int delete)
173 struct in_ifadown_arg arg;
175 KASSERT(ifa->ifa_addr->sa_family == AF_INET,
176 ("%s: wrong family", __func__));
181 rib_foreach_table_walk_del(AF_INET, in_ifadownkill, &arg);
182 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */