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So I've read and tried all I could find on the interwebs and I stil can't get my head around this. I'm trying to accomplish something super easy with OpenVPN on my EdgeRouter X that seems impossible with WireGuard for me: Routing all traffic from LAN over the VPN interface and through to the internet.

Both ends connect fine using wg show showing handshakes and all. On one end the EdgeRouter, on the other a Wireguard Server on AWS EC2.

Basic routing plan is/was (worked with OpenVPN):

  • 0.0.0.0/0 goes to eth0 (local ISP)
  • 0.0.0.0/1 goes to wg0 (VPN)
  • 128.0.0.0/1 goes to wg0 (VPN)

Switching the 2 routes to enabled will drop all internet traffic but LAN devices stay accessible. Router can't even ping 1.1.1.1. Disabling the 2 routes brings back traffic instantly.

One odd thing is wg0 Tx spikes to ~80Mbps when I turn both routes on but nothing for Rx. wg show on the AWS server shows not much packets sent/received and router's show increasing Tx packets, no Rx. I feel like I have something wrong with ports on my router. I tried (not shown in config) to port fwd 54321 to wg0 without success.

Here's my EdgeRouter Config Dump:

firewall {
    all-ping enable
    broadcast-ping disable
    ipv6-name WANv6_IN {
        default-action drop
        description "WAN inbound traffic forwarded to LAN"
        enable-default-log
        rule 10 {
            action accept
            description "Allow established/related sessions"
            state {
                established enable
                related enable
            }
        }
        rule 20 {
            action drop
            description "Drop invalid state"
            state {
                invalid enable
            }
        }
    }
    ipv6-name WANv6_LOCAL {
        default-action drop
        description "WAN inbound traffic to the router"
        enable-default-log
        rule 10 {
            action accept
            description "Allow established/related sessions"
            state {
                established enable
                related enable
            }
        }
        rule 20 {
            action drop
            description "Drop invalid state"
            state {
                invalid enable
            }
        }
        rule 30 {
            action accept
            description "Allow IPv6 icmp"
            protocol ipv6-icmp
        }
        rule 40 {
            action accept
            description "allow dhcpv6"
            destination {
                port 546
            }
            protocol udp
            source {
                port 547
            }
        }
    }
    ipv6-receive-redirects disable
    ipv6-src-route disable
    ip-src-route disable
    log-martians enable
    name WAN_IN {
        default-action drop
        description "WAN to internal"
        rule 20 {
            action accept
            description "Allow established/related"
            state {
                established enable
                related enable
            }
        }
        rule 30 {
            action drop
            description "Drop invalid state"
            state {
                invalid enable
            }
        }
    }
    name WAN_LOCAL {
        default-action drop
        description "WAN to router"
        rule 10 {
            action accept
            description "Allow WG"
            destination {
                port 54321
            }
            log disable
            protocol udp
        }
        rule 30 {
            action accept
            description "Allow established/related"
            state {
                established enable
                related enable
            }
        }
        rule 40 {
            action drop
            description "Drop invalid state"
            state {
                invalid enable
            }
        }
    }
    name WG_LOCAL {
        default-action drop
        description "WG to router"
        enable-default-log
        rule 10 {
            action accept
            description "Allow WG Port"
            destination {
                port 54321
            }
            log enable
            protocol udp
        }
    }
    options {
        mss-clamp {
            interface-type wg
            mss 1380
        }
    }
    receive-redirects disable
    send-redirects enable
    source-validation disable
    syn-cookies enable
}
interfaces {
    ethernet eth0 {
        address dhcp
        description Internet
        duplex auto
        firewall {
            in {
                ipv6-name WANv6_IN
                name WAN_IN
            }
            local {
                ipv6-name WANv6_LOCAL
                name WAN_LOCAL
            }
        }
        speed auto
    }
    ethernet eth1 {
        description Switch
        duplex auto
        speed auto
    }
    ethernet eth2 {
        description Wifi
        duplex auto
        speed auto
    }
    ethernet eth3 {
        description Office
        duplex auto
        speed auto
    }
    ethernet eth4 {
        description Local
        disable
        duplex auto
        poe {
            output off
        }
        speed auto
    }
    loopback lo {
    }
    switch switch0 {
        address 10.0.0.1/24
        description Local
        mtu 1500
        switch-port {
            interface eth1 {
            }
            interface eth2 {
            }
            interface eth3 {
            }
            interface eth4 {
            }
            vlan-aware disable
        }
    }
    wireguard wg0 {
        address 10.50.0.2/32
        description "Wireguard VPN"
        listen-port 54321
        mtu 1420
        peer <peer hash> {
            allowed-ips 0.0.0.0/0
            endpoint 1.2.3.4:54321
            persistent-keepalive 25
            preshared-key /config/auth/preshared.key
        }
        private-key /config/auth/priv.key
        route-allowed-ips false
    }
}
port-forward {
    auto-firewall enable
    hairpin-nat enable
    lan-interface switch0
    wan-interface eth0
}
protocols {
    static {
        interface-route 0.0.0.0/1 {
            next-hop-interface wg0 {
                description "All Local to VPN"
            }
        }
        interface-route 128.0.0.0/1 {
            next-hop-interface wg0 {
                description "All Local to VPN"
            }
        }
    }
}
service {
    dhcp-server {
        disabled false
        hostfile-update disable
        shared-network-name LAN {
            authoritative enable
            subnet 10.0.0.0/24 {
                default-router 10.0.0.1
                dns-server 10.0.0.1
                lease 86400
                start 10.0.0.38 {
                    stop 10.0.0.243
                }
            }
        }
        static-arp disable
        use-dnsmasq disable
    }
    dns {
        forwarding {
            cache-size 150
            listen-on switch0
            name-server 1.1.1.1
            name-server 1.0.0.1
        }
    }
    gui {
        http-port 80
        https-port 443
        older-ciphers enable
    }
    nat {
        rule 5010 {
            description "masquerade for WAN"
            outbound-interface eth0
            type masquerade
        }
        rule 5011 {
            description "masquerade for WG"
            log disable
            outbound-interface wg0
            protocol all
            type masquerade
        }
    }
    ssh {
        port 22
        protocol-version v2
    }
    unms {
        disable
    }
}
system {
    analytics-handler {
        send-analytics-report false
    }
    crash-handler {
        send-crash-report false
    }
    host-name my-net
    login {
        user admin {
            authentication {
                encrypted-password <hash>
            }
            level admin
        }
    }
    ntp {
        server 0.ubnt.pool.ntp.org {
        }
        server 1.ubnt.pool.ntp.org {
        }
        server 2.ubnt.pool.ntp.org {
        }
        server 3.ubnt.pool.ntp.org {
        }
    }
    syslog {
        global {
            facility all {
                level notice
            }
            facility protocols {
                level debug
            }
        }
    }
    time-zone America/Montreal
}
traffic-control {
    smart-queue default {
        download {
            ecn enable
            flows 1024
            fq-quantum 1514
            limit 10240
            rate 105mbit
        }
        upload {
            ecn enable
            flows 1024
            fq-quantum 1514
            limit 10240
            rate 35mbit
        }
        wan-interface eth0
    }
}
pycvalade
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1 Answers1

1

Did you add the 0.0.0.0/1 and 128.0.0.0/1 to the main route table?

What is the IP of the wireguard server you connected to? if you have those 3 routes, and nothing else, then how is your wireguard client going to reach the remote? If you put everything on the main table, then you must also add a static route that goes out your main interface for the IP of the wireguard server.

Your OpenVPN server is probably pushing a route for the special remote_host which the OpenVPN client resolves to whatever IP that it connected to.

If you set the AllowedIPs = 0.0.0.0/0 in your wireguard configuration, wg-quick actually does some magic for you to handle this that is pretty neat and easy.

These ip rules are added, and an additional route table is added.

$ ip rule
32764:  from all lookup main suppress_prefixlength 0
32765:  not from all fwmark 0xca6c lookup 51820
32766:  from all lookup main

# ip route show table 51820
default dev wg0 scope link

The wireguard will by default add a fwmark to all the packets to the value 51820 (51820 is 0xca6c in hex).

The rule from all lookup main suppress_prefixlength 0 will ignore the default route on your main table..

Traffic directly to the wireguard peer external IP will not be marked with the fwmark so it will use the 32766 and go out the default route.

Anyway the point is, you probably don't need or want the 0.0.0.0/1 and 128.0.0.0/1 with wireguard on Linux. It has better ways of handling redirecting the default gateway then what OpenVPN has out of the box.

Zoredache
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