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 "opt_mpath.h"
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/sysctl.h>
39 #include <sys/socket.h>
43 #include <net/if_var.h>
44 #include <net/route.h>
45 #include <net/route/route_ctl.h>
46 #include <net/route/route_var.h>
47 #include <net/route/nhop.h>
48 #include <net/route/shared.h>
51 #include <netinet/in.h>
52 #include <netinet/in_var.h>
53 #include <netinet/ip.h>
54 #include <netinet/ip_icmp.h>
55 #include <netinet/ip_var.h>
59 rib4_preadd(u_int fibnum, const struct sockaddr *addr, const struct sockaddr *mask,
60 struct nhop_object *nh)
62 const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr;
66 /* XXX: RTF_LOCAL && RTF_MULTICAST */
68 rt_flags = nhop_get_rtflags(nh);
70 if (rt_flags & RTF_HOST) {
73 * Backward compatibility:
74 * if the destination is broadcast,
75 * mark route as broadcast.
76 * This behavior was useful when route cloning
77 * was in place, so there was an explicit cloned
78 * route for every broadcasted address.
79 * Currently (2020-04) there is no kernel machinery
80 * to do route cloning, though someone might explicitly
81 * add these routes to support some cases with active-active
82 * load balancing. Given that, retain this support.
84 if (in_broadcast(addr4->sin_addr, nh->nh_ifp)) {
85 rt_flags |= RTF_BROADCAST;
86 nhop_set_rtflags(nh, rt_flags);
87 nh->nh_flags |= NHF_BROADCAST;
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 /* Ensure that default route nhop has special flag */
102 const struct sockaddr_in *mask4 = (const struct sockaddr_in *)mask;
103 if ((rt_flags & RTF_HOST) == 0 && mask4 != NULL &&
104 mask4->sin_addr.s_addr == 0)
105 nh->nh_flags |= NHF_DEFAULT;
107 /* Set nhop type to basic per-AF nhop */
108 if (nhop_get_type(nh) == 0) {
109 if (nh->nh_flags & NHF_GATEWAY)
110 nh_type = NH_TYPE_IPV4_ETHER_NHOP;
112 nh_type = NH_TYPE_IPV4_ETHER_RSLV;
114 nhop_set_type(nh, nh_type);
121 * Initialize our routing tree.
124 in_inithead(uint32_t fibnum)
128 rh = rt_table_init(32, AF_INET, fibnum);
132 rh->rnh_preadd = rib4_preadd;
134 rt_mpath_init_rnh(rh);
142 in_detachhead(struct rib_head *rh)
145 rt_table_destroy(rh);
150 * This zaps old routes when the interface goes down or interface
151 * address is deleted. In the latter case, it deletes static routes
152 * that point to this address. If we don't do this, we may end up
153 * using the old address in the future. The ones we always want to
154 * get rid of are things like ARP entries, since the user might down
155 * the interface, walk over to a completely different network, and
158 struct in_ifadown_arg {
164 in_ifadownkill(const struct rtentry *rt, const struct nhop_object *nh,
167 struct in_ifadown_arg *ap = xap;
169 if (nh->nh_ifa != ap->ifa)
172 if ((nhop_get_rtflags(nh) & RTF_STATIC) != 0 && ap->del == 0)
179 in_ifadown(struct ifaddr *ifa, int delete)
181 struct in_ifadown_arg arg;
183 KASSERT(ifa->ifa_addr->sa_family == AF_INET,
184 ("%s: wrong family", __func__));
189 rt_foreach_fib_walk_del(AF_INET, in_ifadownkill, &arg);
190 ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */