ead85fe415
Having metadata such as fibnum or vnet in the struct rib_head is handy as it eases building functionality in the routing space. This change is required to properly bring back route redirect support. Reviewed by: bz MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D23047
328 lines
8.2 KiB
C
328 lines
8.2 KiB
C
/* $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 "opt_inet.h"
|
|
#include "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;
|
|
}
|
|
|
|
uint32_t
|
|
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, u_int fibnum);
|
|
extern int in_inithead(void **head, int off, u_int fibnum);
|
|
|
|
#ifdef INET
|
|
int
|
|
rn4_mpath_inithead(void **head, int off, u_int fibnum)
|
|
{
|
|
struct rib_head *rnh;
|
|
|
|
hashjitter = arc4random();
|
|
if (in_inithead(head, off, fibnum) == 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, u_int fibnum)
|
|
{
|
|
struct rib_head *rnh;
|
|
|
|
hashjitter = arc4random();
|
|
if (in6_inithead(head, off, fibnum) == 1) {
|
|
rnh = (struct rib_head *)*head;
|
|
rnh->rnh_multipath = 1;
|
|
return 1;
|
|
} else
|
|
return 0;
|
|
}
|
|
|
|
#endif
|