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# $OpenBSD: bgpd.conf,v 1.11 2018/08/28 17:52:16 job Exp $
# example bgpd configuration file, see bgpd.conf(5)
# define our own ASN as a macro
ASN="65001"
# global configuration
AS $ASN
router-id 192.0.2.1
# Generate routes for the networks our ASN will originate.
# The communities (read 'tags') are later used to match on what
# is announced to EBGP neighbors
network 192.0.2.0/24 set large-community $ASN:1:1
network 2001:db8:abcd::/48 set large-community $ASN:1:1
# list of networks that may be originated by our ASN
prefix-set mynetworks { \
192.0.2.0/24 \
2001:db8:abcd::/48 \
}
# this prefix-set is used to protect against accepting
# hijacks of our own originated address space
prefix-set mynetworks_orlonger { \
192.0.2.0/24 or-longer \
2001:db8:abcd::/48 or-longer \
}
# assume simple network with 3 routers in IBGP full mesh
group "ibgp mesh v4" {
remote-as $ASN
# use loopback for IBGP sessions, assume its distributed in OSPF
local-address 192.0.2.1
neighbor 192.0.2.2 # router 2 ipv4
neighbor 192.0.2.3 # router 3 ipv4
}
# define the IPv6 IBGP sessions
group "ibgp mesh v6" {
remote-as $ASN
local-address 2001:db8:abcd::1
neighbor 2001:db8:abcd::2 # router 2 ipv6
neighbor 2001:db8:abcd::3 # router 3 ipv6
}
# upstream providers
group "upstreams" {
neighbor 203.0.113.1 {
remote-as 65002
descr "IPv4 Transit Provider A"
}
neighbor 198.51.100.0 {
remote-as 65123
descr "IPv4 Transit provider B"
}
neighbor 2001:db8:666::2 {
remote-as 65123
descr "IPv6 Transit provider B"
}
}
## rules section
# uncomment the following two lines to accept a default route from upstreams
#allow from group upstreams prefix 0.0.0.0/0
#allow from group upstreams prefix ::/0
### for simple BGP setups, no editing below this line is required ###
# Outbound EBGP: only allow self originated networks to ebgp peers
# Don't leak any routes from upstream or peering sessions. This is done
# by checking for routes that are tagged with the large-community $ASN:1:1
allow to ebgp prefix-set mynetworks large-community $ASN:1:1
# deny more-specifics of our own originated prefixes
deny quick from ebgp prefix-set mynetworks_orlonger
# IBGP: allow all updates to and from our IBGP neighbors
allow from ibgp
allow to ibgp
# Scrub normal and large communities relevant to our ASN from EBGP neighbors
# https://tools.ietf.org/html/rfc7454#section-11
match from ebgp set { community delete $ASN:* }
match from ebgp set { large-community delete $ASN:*:* }
# filter out prefixes longer than 24 or shorter than 8 bits for IPv4
# and longer than 48 or shorter than 16 bits for IPv6.
allow from any inet prefixlen 8 - 24
allow from any inet6 prefixlen 16 - 48
# Honor requests to gracefully shutdown BGP sessions
# https://tools.ietf.org/html/rfc8326
match from any community GRACEFUL_SHUTDOWN set { localpref 0 }
# See http://bgpfilterguide.nlnog.net/guides/bogon_prefixes/ for
# an elaboration why each prefix is a bogon
prefix-set bogons { \
0.0.0.0/8 or-longer, 10.0.0.0/8 or-longer, \
100.64.0.0/10 or-longer, 127.0.0.0/8 or-longer, \
169.254.0.0/16 or-longer, 172.16.0.0/12 or-longer, \
192.0.2.0/24 or-longer, 192.88.99.0/24 or-longer, \
192.168.0.0/16 or-longer, 198.18.0.0/15 or-longer, \
198.51.100.0/24 or-longer, 203.0.113.0/24 or-longer, \
224.0.0.0/4 or-longer, 240.0.0.0/4 or-longer, \
::/8 or-longer, 0100::/64 or-longer, \
2001:2::/48 or-longer, 2001:10::/28 or-longer, \
2001:db8::/32 or-longer, 2002::/16 or-longer, \
3ffe::/16 or-longer, fc00::/7 or-longer, \
fe80::/10 or-longer, fec0::/10 or-longer, \
ff00::/8 or-longer \
}
# use above prefix-set to reject the bogons
deny quick from any prefix-set bogons
# filter bogon AS numbers
# see http://bgpfilterguide.nlnog.net/guides/bogon_asns/ for more
# information why these ASNs are bogons.
deny quick from any AS 23456
deny quick from any AS 64496 - 131071
deny quick from any AS 4200000000 - 4294967295
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