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/route_ctl.h>
44 #include <net/route/route_var.h>
45 #include <net/route/nhop.h>
48 #include <netinet/in.h>
49 #include <netinet/in_var.h>
50 #include <netinet/ip.h>
51 #include <netinet/ip_icmp.h>
52 #include <netinet/ip_var.h>
55 rib4_set_nh_pfxflags(u_int fibnum, const struct sockaddr *addr, const struct sockaddr *mask,
56 struct nhop_object *nh)
58 const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr;
59 const struct sockaddr_in *mask4 = (const struct sockaddr_in *)mask;
60 bool is_broadcast = false;
63 nhop_set_pxtype_flag(nh, NHF_HOST);
65 * Backward compatibility:
66 * if the destination is broadcast,
67 * mark route as broadcast.
68 * This behavior was useful when route cloning
69 * was in place, so there was an explicit cloned
70 * route for every broadcasted address.
71 * Currently (2020-04) there is no kernel machinery
72 * to do route cloning, though someone might explicitly
73 * add these routes to support some cases with active-active
74 * load balancing. Given that, retain this support.
76 if (in_broadcast(addr4->sin_addr, nh->nh_ifp))
78 } else if (mask4->sin_addr.s_addr == 0)
79 nhop_set_pxtype_flag(nh, NHF_DEFAULT);
81 nhop_set_pxtype_flag(nh, 0);
83 nhop_set_broadcast(nh, is_broadcast);
89 rib4_augment_nh(u_int fibnum, struct nhop_object *nh)
93 * inherit interface MTU if not set or
94 * check if MTU is too large.
96 if (nh->nh_mtu == 0) {
97 nh->nh_mtu = nh->nh_ifp->if_mtu;
98 } else if (nh->nh_mtu > nh->nh_ifp->if_mtu)
99 nh->nh_mtu = nh->nh_ifp->if_mtu;
101 /* Set nhop type to basic per-AF nhop */
102 if (nhop_get_type(nh) == 0) {
104 if (nh->nh_flags & NHF_GATEWAY)
105 nh_type = NH_TYPE_IPV4_ETHER_NHOP;
107 nh_type = NH_TYPE_IPV4_ETHER_RSLV;
109 nhop_set_type(nh, nh_type);
116 * Initialize our routing tree.
119 in_inithead(uint32_t fibnum)
123 rh = rt_table_init(32, AF_INET, fibnum);
127 rh->rnh_set_nh_pfxflags = rib4_set_nh_pfxflags;
128 rh->rnh_augment_nh = rib4_augment_nh;
135 in_detachhead(struct rib_head *rh)
138 rt_table_destroy(rh);
143 * This zaps old routes when the interface goes down or interface
144 * address is deleted. In the latter case, it deletes static routes
145 * that point to this address. If we don't do this, we may end up
146 * using the old address in the future. The ones we always want to
147 * get rid of are things like ARP entries, since the user might down
148 * the interface, walk over to a completely different network, and
151 struct in_ifadown_arg {
157 in_ifadownkill(const struct rtentry *rt, const struct nhop_object *nh,
160 struct in_ifadown_arg *ap = xap;
162 if (nh->nh_ifa != ap->ifa)
165 if ((nhop_get_rtflags(nh) & RTF_STATIC) != 0 && ap->del == 0)
172 in_ifadown(struct ifaddr *ifa, int delete)
174 struct in_ifadown_arg arg;
176 KASSERT(ifa->ifa_addr->sa_family == AF_INET,
177 ("%s: wrong family", __func__));
182 rib_foreach_table_walk_del(AF_INET, in_ifadownkill, &arg);
183 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */