freebsd-skq/usr.bin/netstat/common.h
Alexander V. Chernikov fedeb08b6a Introduce scalable route multipath.
This change is based on the nexthop objects landed in D24232.

The change introduces the concept of nexthop groups.
Each group contains the collection of nexthops with their
 relative weights and a dataplane-optimized structure to enable
 efficient nexthop selection.

Simular to the nexthops, nexthop groups are immutable. Dataplane part
 gets compiled during group creation and is basically an array of
 nexthop pointers, compiled w.r.t their weights.

With this change, `rt_nhop` field of `struct rtentry` contains either
 nexthop or nexthop group. They are distinguished by the presense of
 NHF_MULTIPATH flag.
All dataplane lookup functions returns pointer to the nexthop object,
leaving nexhop groups details inside routing subsystem.

User-visible changes:

The change is intended to be backward-compatible: all non-mpath operations
 should work as before with ROUTE_MPATH and net.route.multipath=1.

All routes now comes with weight, default weight is 1, maximum is 2^24-1.

Current maximum multipath group width is statically set to 64.
 This will become sysctl-tunable in the followup changes.

Using functionality:
* Recompile kernel with ROUTE_MPATH
* set net.route.multipath to 1

route add -6 2001:db8::/32 2001:db8::2 -weight 10
route add -6 2001:db8::/32 2001:db8::3 -weight 20

netstat -6On

Nexthop groups data

Internet6:
GrpIdx  NhIdx     Weight   Slots                                 Gateway     Netif  Refcnt
1         ------- ------- ------- --------------------------------------- ---------       1
              13      10       1                             2001:db8::2     vlan2
              14      20       2                             2001:db8::3     vlan2

Next steps:
* Land outbound hashing for locally-originated routes ( D26523 ).
* Fix net/bird multipath (net/frr seems to work fine)
* Add ROUTE_MPATH to GENERIC
* Set net.route.multipath=1 by default

Tested by:	olivier
Reviewed by:	glebius
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D26449
2020-10-03 10:47:17 +00:00

76 lines
2.5 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1992, 1993
* Regents of the University of California. 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 University 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 REGENTS 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 REGENTS 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.
*
* @(#)netstat.h 8.2 (Berkeley) 1/4/94
* $FreeBSD$
*/
#ifndef _NETSTAT_COMMON_H_
#define _NETSTAT_COMMON_H_
struct bits {
u_long b_mask;
char b_val;
const char *b_name;
};
extern struct bits rt_bits[];
const char *fmt_flags(const struct bits *p, int f);
void print_flags_generic(int flags, const struct bits *pbits,
const char *format, const char *tag_name);
int print_sockaddr(const char *name, struct sockaddr *sa,
struct sockaddr *mask, int flags, int width);
struct ifmap_entry {
char ifname[IFNAMSIZ];
};
struct ifmap_entry *prepare_ifmap(size_t *ifmap_size);
struct rt_msghdr;
struct nhops_map {
uint32_t idx;
struct rt_msghdr *rtm;
};
struct nhops_dump {
void *nh_buf;
struct nhops_map *nh_map;
size_t nh_count;
};
void dump_nhops_sysctl(int fibnum, int af, struct nhops_dump *nd);
struct nhop_map;
void nhop_map_update(struct nhop_map *map, uint32_t idx, char *gw, char *ifname);
#endif