/*-
* Copyright 1994, 1995 Massachusetts Institute of Technology
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that both the above copyright notice and this
* permission notice appear in all copies, that both the above
* copyright notice and this permission notice appear in all
* supporting documentation, and that the name of M.I.T. not be used
* in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission. M.I.T. makes
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
* SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <sys/mbuf.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/route/route_ctl.h>
#include <net/route/route_var.h>
#include <net/route/nhop.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip_var.h>
static int
rib4_preadd(u_int fibnum, const struct sockaddr *addr, const struct sockaddr *mask,
struct nhop_object *nh)
{
const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr;
uint16_t nh_type;
int rt_flags;
/* XXX: RTF_LOCAL && RTF_MULTICAST */
rt_flags = nhop_get_rtflags(nh);
if (rt_flags & RTF_HOST) {
/*
* Backward compatibility:
* if the destination is broadcast,
* mark route as broadcast.
* This behavior was useful when route cloning
* was in place, so there was an explicit cloned
* route for every broadcasted address.
* Currently (2020-04) there is no kernel machinery
* to do route cloning, though someone might explicitly
* add these routes to support some cases with active-active
* load balancing. Given that, retain this support.
*/
if (in_broadcast(addr4->sin_addr, nh->nh_ifp)) {
rt_flags |= RTF_BROADCAST;
nhop_set_rtflags(nh, rt_flags);
nh->nh_flags |= NHF_BROADCAST;
}
}
/*
* Check route MTU:
* inherit interface MTU if not set or
* check if MTU is too large.
*/
if (nh->nh_mtu == 0) {
nh->nh_mtu = nh->nh_ifp->if_mtu;
} else if (nh->nh_mtu > nh->nh_ifp->if_mtu)
nh->nh_mtu = nh->nh_ifp->if_mtu;
/* Ensure that default route nhop has special flag */
const struct sockaddr_in *mask4 = (const struct sockaddr_in *)mask;
if ((rt_flags & RTF_HOST) == 0 && mask4 != NULL &&
mask4->sin_addr.s_addr == 0)
nh->nh_flags |= NHF_DEFAULT;
/* Set nhop type to basic per-AF nhop */
if (nhop_get_type(nh) == 0) {
if (nh->nh_flags & NHF_GATEWAY)
nh_type = NH_TYPE_IPV4_ETHER_NHOP;
else
nh_type = NH_TYPE_IPV4_ETHER_RSLV;
nhop_set_type(nh, nh_type);
}
return (0);
}
/*
* Initialize our routing tree.
*/
struct rib_head *
in_inithead(uint32_t fibnum)
{
struct rib_head *rh;
rh = rt_table_init(32, AF_INET, fibnum);
if (rh == NULL)
return (NULL);
rh->rnh_preadd = rib4_preadd;
return (rh);
}
#ifdef VIMAGE
void
in_detachhead(struct rib_head *rh)
{
rt_table_destroy(rh);
}
#endif
/*
* This zaps old routes when the interface goes down or interface
* address is deleted. In the latter case, it deletes static routes
* that point to this address. If we don't do this, we may end up
* using the old address in the future. The ones we always want to
* get rid of are things like ARP entries, since the user might down
* the interface, walk over to a completely different network, and
* plug back in.
*/
struct in_ifadown_arg {
struct ifaddr *ifa;
int del;
};
static int
in_ifadownkill(const struct rtentry *rt, const struct nhop_object *nh,
void *xap)
{
struct in_ifadown_arg *ap = xap;
if (nh->nh_ifa != ap->ifa)
return (0);
if ((nhop_get_rtflags(nh) & RTF_STATIC) != 0 && ap->del == 0)
return (0);
return (1);
}
void
in_ifadown(struct ifaddr *ifa, int delete)
{
struct in_ifadown_arg arg;
KASSERT(ifa->ifa_addr->sa_family == AF_INET,
("%s: wrong family", __func__));
arg.ifa = ifa;
arg.del = delete;
rib_foreach_table_walk_del(AF_INET, in_ifadownkill, &arg);
ifa->ifa_flags &= ~IFA_ROUTE; /* XXXlocking? */
}
