Firewall problems

znidaxp · October 13, 2024, 10:26am

I have problems with firewall. All other setting are default. One WAN one LAN.

First problem: I set port forwaring and gave it a ipset for src_ip.The connections get through even if the IP in not in allowed list. Sometimes. Restarted router.

Second: I disabled Ping in Traffic rules and can still ping my router. Also tried restaring router in both cases. I disabled all but "Allow-DHCP-Renew" traffic rule. Can still ping in with my phone with LTE connection.

brada4 · October 13, 2024, 10:45am

Ping from LAN is always permitted

Please connect to your OpenWrt device using ssh and copy the output of the following commands and post it here using the "Preformatted text </> " button:

Remember to redact passwords, MAC addresses and any public IP addresses you may have:

ubus call system board
cat /etc/config/network
cat /etc/config/firewall

frollic · October 13, 2024, 11:06am

Doing this from where, connection wise.

znidaxp · October 13, 2024, 2:37pm

I disabled the ipset for now, so it is not implemented, but setup like this I had problems.

root@OpenWrt:~# ubus call system board
{
        "kernel": "5.15.167",
        "hostname": "OpenWrt",
        "system": "ARMv8 Processor rev 4",
        "model": "Xiaomi Mi Router AX3000T (OpenWrt U-Boot layout)",
        "board_name": "xiaomi,mi-router-ax3000t-ubootmod",
        "rootfs_type": "squashfs",
        "release": {
                "distribution": "OpenWrt",
                "version": "23.05.5",
                "revision": "r24106-10cc5fcd00",
                "target": "mediatek/filogic",
                "description": "OpenWrt 23.05.5 r24106-10cc5fcd00"
        }
}

root@OpenWrt:~# cat /etc/config/network

config interface 'loopback'
        option device 'lo'
        option proto 'static'
        option ipaddr '127.0.0.1'
        option netmask '255.0.0.0'

config globals 'globals'
        option ula_prefix 'XXXX::/48'

config device
        option name 'br-lan'
        option type 'bridge'
        list ports 'lan2'
        list ports 'lan3'
        list ports 'lan4'

config interface 'lan'
        option device 'br-lan'
        option proto 'static'
        option ip6assign '60'
        list ipaddr '192.168.XX.254/24'

config device
        option name 'wan'
        option macaddr 'XXXX'
        option ipv6 '0'

config interface 'wan'
        option device 'wan'
        option proto 'dhcp'

config route
        option interface 'lan'
        option target '192.168.0.0/24'
        option gateway '192.168.XX.201'

root@OpenWrt:~# cat /etc/config/firewall

config defaults
        option input 'REJECT'
        option output 'ACCEPT'
        option forward 'REJECT'
        option synflood_protect '1'

config zone
        option name 'lan'
        option input 'ACCEPT'
        option output 'ACCEPT'
        option forward 'ACCEPT'
        list network 'lan'

config zone
        option name 'wan'
        option input 'REJECT'
        option output 'ACCEPT'
        option forward 'REJECT'
        option masq '1'
        option mtu_fix '1'
        list network 'wan'

config rule
        option name 'Allow-DHCP-Renew'
        option src 'wan'
        option proto 'udp'
        option dest_port '68'
        option target 'ACCEPT'
        option family 'ipv4'

config rule
        option name 'Allow-Ping'
        option src 'wan'
        option proto 'icmp'
        option family 'ipv4'
        option target 'ACCEPT'
        list icmp_type 'echo-request'
        option enabled '0'

config rule
        option name 'Allow-IGMP'
        option src 'wan'
        option proto 'igmp'
        option family 'ipv4'
        option target 'ACCEPT'
        option enabled '0'

config rule
        option name 'Allow-DHCPv6'
        option src 'wan'
        option proto 'udp'
        option dest_port '546'
        option family 'ipv6'
        option target 'ACCEPT'
        option enabled '0'

config rule
        option name 'Allow-MLD'
        option src 'wan'
        option proto 'icmp'
        option src_ip 'fe80::/10'
        list icmp_type '130/0'
        list icmp_type '131/0'
        list icmp_type '132/0'
        list icmp_type '143/0'
        option family 'ipv6'
        option target 'ACCEPT'
        option enabled '0'

config rule
        option name 'Allow-ICMPv6-Input'
        option src 'wan'
        option proto 'icmp'
        list icmp_type 'echo-request'
        list icmp_type 'echo-reply'
        list icmp_type 'destination-unreachable'
        list icmp_type 'packet-too-big'
        list icmp_type 'time-exceeded'
        list icmp_type 'bad-header'
        list icmp_type 'unknown-header-type'
        list icmp_type 'router-solicitation'
        list icmp_type 'neighbour-solicitation'
        list icmp_type 'router-advertisement'
        list icmp_type 'neighbour-advertisement'
        option limit '1000/sec'
        option family 'ipv6'
        option target 'ACCEPT'
        option enabled '0'

config rule
        option name 'Allow-ICMPv6-Forward'
        option src 'wan'
        option dest '*'
        option proto 'icmp'
        list icmp_type 'echo-request'
        list icmp_type 'echo-reply'
        list icmp_type 'destination-unreachable'
        list icmp_type 'packet-too-big'
        list icmp_type 'time-exceeded'
        list icmp_type 'bad-header'
        list icmp_type 'unknown-header-type'
        option limit '1000/sec'
        option family 'ipv6'
        option target 'ACCEPT'
        option enabled '0'

config rule
        option name 'Allow-IPSec-ESP'
        option src 'wan'
        option dest 'lan'
        option proto 'esp'
        option target 'ACCEPT'
        option enabled '0'

config rule
        option name 'Allow-ISAKMP'
        option src 'wan'
        option dest 'lan'
        option dest_port '500'
        option proto 'udp'
        option target 'ACCEPT'
        option enabled '0'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'caddy 80'
        option src 'wan'
        option src_dport '80'
        option dest_ip '192.168.XX.203'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'caddy 443'
        option src 'wan'
        option src_dport '443'
        option dest_ip '192.168.XX.203'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'caddy hassio'
        option src 'wan'
        option src_dport 'XXXXX'
        option dest_ip '192.168.XX.203'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'XXX IN'
        list proto 'tcp'
        option src 'wan'
        option src_dport 'XXXX'
        option dest_ip '192.168.XX.204'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'XXX OUT'
        list proto 'tcp'
        option src 'wan'
        option src_dport 'XXXX'
        option dest_ip '192.168.XX.204'
        option enabled '0'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'wg c2v'
        list proto 'udp'
        option src 'wan'
        option src_dport '51821'
        option dest_ip '192.168.XX.201'

config redirect
        option dest 'lan'
        option target 'DNAT'
        option name 'wg'
        list proto 'udp'
        option src 'wan'
        option src_dport '51820'
        option dest_ip '192.168.XX.201'

config forwarding
        option src 'lan'
        option dest 'wan'

config ipset
        option name 'allowed_ips_wg'
        option family 'ipv4'
        list match 'src_ip'
        list entry 'X.X.X.X'
        list entry 'X.X.X.X'

znidaxp · October 13, 2024, 2:38pm

Connection is a LTE connection from my phone, with Wifi off. It has my mobile carrier IP. And I ping my home IP. I guess a port is still open.

psherman · October 13, 2024, 2:56pm

There is a high probability that one or both of the following apply to your connection wrt IPv4:

you are behind NAT/CG-NAT from the carrier. This would mean that your phone wouldn’t have a public IPv4 address and therefore would not be reachable for inbound connections
Your phone likely applies a NAT layer of its own, providing an RFC1918 address to the downstream device (your router). This would require that you have a means of port forwarding though the phone. I don’t know if most phones have this capability exposed (I’ve never seen it on iOS, not sure about Android).

What are the first two octets of your openwrt wan (in bold: aaa.bbb.ccc.ddd):

ifstatus wan | grep address

znidaxp · October 13, 2024, 3:21pm

I guess I didnt tell all the info. My ISP modem has DMZ (192.168.100.X) for a OpenWRT WAN port. So all ports forward to OpenWRT.

I try to ping my home IP from my phone, not the other way around. I understand I cant ping CGNAT IP.

Problem is I CAN ping my home IP from anywhere, but this setting is disabled on OpenWRT.

brada4 · October 13, 2024, 3:28pm

No, it is not how it works.
Check with PC to mobile then via openwrt:

znidaxp · October 13, 2024, 3:38pm

I don't understand how this apply to my problem. Problem is I CAN ping my home IP from anywhere, but this setting is disabled on OpenWRT(option Allow-Ping is off). This was not possible with my old router (FreshTomato).

frollic · October 13, 2024, 3:51pm

Question is, are you really pinging your WAN IP, or the carriers/ISPs public end point IP ?

znidaxp · October 13, 2024, 4:06pm

I will have to unplug OpenWRT and see. Maybe ISP router is responding. I was thinking since I DMZ my OpenWRT only router will respond.

frollic · October 13, 2024, 4:28pm

If you answer @psherman's question from 2h ago, we'll know.

znidaxp · October 13, 2024, 5:05pm

OpenWRT WAN: 192.168.100.X which is DMZ on ISP Router.

PS: I have tried unpluging OpenWRT. I guess ISP router is responding to Ping requests.

What about my first problem: Is it possible that if the connection is established before ipset is enabled it ignores those connections? I tried rebooting the router.

frollic · October 13, 2024, 5:08pm

That's not your public IP though, Openwrt has nothing to do with it.

brada4 · October 13, 2024, 5:31pm

You can not open public port if you are fronted by ISP router with another nat.
Can you show nat type with pc behind provider's router? If it is 4th type there is no hope.

znidaxp · October 14, 2024, 8:51am

Type: Port Restricted Cone.

The only problem left is with ipset. With ping it was the ISP modem that was responding.

brada4 · October 14, 2024, 9:07am

Please provide complete answers. There is no actionable info in ur onelines

znidaxp · October 14, 2024, 6:22pm

The ping part of the question has been resolved. It was a reponse from ISP modem and not OpenWRT router. My bad, I thought DMZing a device meant ping requsts will also be forwarded. If I understand correctly IGMP is not forwarded. You learn every day.

PS: I have figure out the first part also. If the connection is already established (in my case Wireguard connection) and the ipset list is changed to exclude that IP the connection must first be killed (router restart helps but there is probably better solution).

Sorry for my post, I didn't research enough on my own and posted this too fast.

system · October 24, 2024, 6:22pm

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