#include <machine/rtems-bsd-kernel-space.h>
/* $KAME: radix_mpath.c,v 1.17 2004/11/08 10:29:39 itojun Exp $ */
/*
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (C) 2001 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS 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.
* THE AUTHORS DO NOT GUARANTEE THAT THIS SOFTWARE DOES NOT INFRINGE
* ANY OTHERS' INTELLECTUAL PROPERTIES. IN NO EVENT SHALL THE AUTHORS
* BE LIABLE FOR ANY INFRINGEMENT OF ANY OTHERS' INTELLECTUAL
* PROPERTIES.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <rtems/bsd/local/opt_inet.h>
#include <rtems/bsd/local/opt_inet6.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/domain.h>
#include <sys/syslog.h>
#include <net/radix.h>
#include <net/radix_mpath.h>
#include <sys/rmlock.h>
#include <net/route.h>
#include <net/route_var.h>
#include <net/if.h>
#include <net/if_var.h>
/*
* give some jitter to hash, to avoid synchronization between routers
*/
static uint32_t hashjitter;
int
rt_mpath_capable(struct rib_head *rnh)
{
return rnh->rnh_multipath;
}
int
rn_mpath_capable(struct radix_head *rh)
{
return (rt_mpath_capable((struct rib_head *)rh));
}
struct radix_node *
rn_mpath_next(struct radix_node *rn)
{
struct radix_node *next;
if (!rn->rn_dupedkey)
return NULL;
next = rn->rn_dupedkey;
if (rn->rn_mask == next->rn_mask)
return next;
else
return NULL;
}
#ifndef __rtems__
uint32_t
#else /* __rtems__ */
u_int32_t
#endif /* __rtems__ */
rn_mpath_count(struct radix_node *rn)
{
uint32_t i = 0;
struct rtentry *rt;
while (rn != NULL) {
rt = (struct rtentry *)rn;
i += rt->rt_weight;
rn = rn_mpath_next(rn);
}
return (i);
}
struct rtentry *
rt_mpath_matchgate(struct rtentry *rt, struct sockaddr *gate)
{
struct radix_node *rn;
if (!gate || !rt->rt_gateway)
return NULL;
/* beyond here, we use rn as the master copy */
rn = (struct radix_node *)rt;
do {
rt = (struct rtentry *)rn;
/*
* we are removing an address alias that has
* the same prefix as another address
* we need to compare the interface address because
* rt_gateway is a special sockadd_dl structure
*/
if (rt->rt_gateway->sa_family == AF_LINK) {
if (!memcmp(rt->rt_ifa->ifa_addr, gate, gate->sa_len))
break;
}
/*
* Check for other options:
* 1) Routes with 'real' IPv4/IPv6 gateway
* 2) Loopback host routes (another AF_LINK/sockadd_dl check)
* */
if (rt->rt_gateway->sa_len == gate->sa_len &&
!memcmp(rt->rt_gateway, gate, gate->sa_len))
break;
} while ((rn = rn_mpath_next(rn)) != NULL);
return (struct rtentry *)rn;
}
/*
* go through the chain and unlink "rt" from the list
* the caller will free "rt"
*/
int
rt_mpath_deldup(struct rtentry *headrt, struct rtentry *rt)
{
struct radix_node *t, *tt;
if (!headrt || !rt)
return (0);
t = (struct radix_node *)headrt;
tt = rn_mpath_next(t);
while (tt) {
if (tt == (struct radix_node *)rt) {
t->rn_dupedkey = tt->rn_dupedkey;
tt->rn_dupedkey = NULL;
tt->rn_flags &= ~RNF_ACTIVE;
tt[1].rn_flags &= ~RNF_ACTIVE;
return (1);
}
t = tt;
tt = rn_mpath_next((struct radix_node *)t);
}
return (0);
}
/*
* check if we have the same key/mask/gateway on the table already.
* Assume @rt rt_key host bits are cleared according to @netmask
*/
int
rt_mpath_conflict(struct rib_head *rnh, struct rtentry *rt,
struct sockaddr *netmask)
{
struct radix_node *rn, *rn1;
struct rtentry *rt1;
rn = (struct radix_node *)rt;
rn1 = rnh->rnh_lookup(rt_key(rt), netmask, &rnh->head);
if (!rn1 || rn1->rn_flags & RNF_ROOT)
return (0);
/* key/mask are the same. compare gateway for all multipaths */
do {
rt1 = (struct rtentry *)rn1;
/* sanity: no use in comparing the same thing */
if (rn1 == rn)
continue;
if (rt1->rt_gateway->sa_family == AF_LINK) {
if (rt1->rt_ifa->ifa_addr->sa_len != rt->rt_ifa->ifa_addr->sa_len ||
bcmp(rt1->rt_ifa->ifa_addr, rt->rt_ifa->ifa_addr,
rt1->rt_ifa->ifa_addr->sa_len))
continue;
} else {
if (rt1->rt_gateway->sa_len != rt->rt_gateway->sa_len ||
bcmp(rt1->rt_gateway, rt->rt_gateway,
rt1->rt_gateway->sa_len))
continue;
}
/* all key/mask/gateway are the same. conflicting entry. */
return (EEXIST);
} while ((rn1 = rn_mpath_next(rn1)) != NULL);
return (0);
}
static struct rtentry *
rt_mpath_selectrte(struct rtentry *rte, uint32_t hash)
{
struct radix_node *rn0, *rn;
uint32_t total_weight;
struct rtentry *rt;
int64_t weight;
/* beyond here, we use rn as the master copy */
rn0 = rn = (struct radix_node *)rte;
rt = rte;
/* gw selection by Modulo-N Hash (RFC2991) XXX need improvement? */
total_weight = rn_mpath_count(rn0);
hash += hashjitter;
hash %= total_weight;
for (weight = abs((int32_t)hash);
rt != NULL && weight >= rt->rt_weight;
weight -= (rt == NULL) ? 0 : rt->rt_weight) {
/* stay within the multipath routes */
if (rn->rn_dupedkey && rn->rn_mask != rn->rn_dupedkey->rn_mask)
break;
rn = rn->rn_dupedkey;
rt = (struct rtentry *)rn;
}
return (rt);
}
struct rtentry *
rt_mpath_select(struct rtentry *rte, uint32_t hash)
{
if (rn_mpath_next((struct radix_node *)rte) == NULL)
return (rte);
return (rt_mpath_selectrte(rte, hash));
}
void
rtalloc_mpath_fib(struct route *ro, uint32_t hash, u_int fibnum)
{
struct rtentry *rt;
/*
* XXX we don't attempt to lookup cached route again; what should
* be done for sendto(3) case?
*/
if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP)
&& RT_LINK_IS_UP(ro->ro_rt->rt_ifp))
return;
ro->ro_rt = rtalloc1_fib(&ro->ro_dst, 1, 0, fibnum);
/* if the route does not exist or it is not multipath, don't care */
if (ro->ro_rt == NULL)
return;
if (rn_mpath_next((struct radix_node *)ro->ro_rt) == NULL) {
RT_UNLOCK(ro->ro_rt);
return;
}
rt = rt_mpath_selectrte(ro->ro_rt, hash);
/* XXX try filling rt_gwroute and avoid unreachable gw */
/* gw selection has failed - there must be only zero weight routes */
if (!rt) {
RT_UNLOCK(ro->ro_rt);
ro->ro_rt = NULL;
return;
}
if (ro->ro_rt != rt) {
RTFREE_LOCKED(ro->ro_rt);
ro->ro_rt = rt;
RT_LOCK(ro->ro_rt);
RT_ADDREF(ro->ro_rt);
}
RT_UNLOCK(ro->ro_rt);
}
extern int in6_inithead(void **head, int off);
extern int in_inithead(void **head, int off);
#ifdef INET
int
rn4_mpath_inithead(void **head, int off)
{
struct rib_head *rnh;
hashjitter = arc4random();
if (in_inithead(head, off) == 1) {
rnh = (struct rib_head *)*head;
rnh->rnh_multipath = 1;
return 1;
} else
return 0;
}
#endif
#ifdef INET6
int
rn6_mpath_inithead(void **head, int off)
{
struct rib_head *rnh;
hashjitter = arc4random();
if (in6_inithead(head, off) == 1) {
rnh = (struct rib_head *)*head;
rnh->rnh_multipath = 1;
return 1;
} else
return 0;
}
#endif
