this post was submitted on 16 Aug 2024
15 points (94.1% liked)

Linux

47345 readers
1260 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS
 

I installed WireGuard on my host and set this configuration /etc/wireguard/wg0.conf:

[Interface]
Address = 10.0.0.1/24
ListenPort = 51820
PrivateKey = [REDACTED]
PostUp = iptables -A FORWARD -i %i -j ACCEPT; iptables -t nat -A POSTROUTING -o ens3 -j MASQUERADE
PostDown = iptables -D FORWARD -i %i -j ACCEPT; iptables -t nat -D POSTROUTING -o ens3 -j MASQUERADE


[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.2/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.3/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.4/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.5/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.6/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.7/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.8/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.9/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.10/32

[Peer]
PublicKey = [REDACTED]
PresharedKey = [REDACTED]
AllowedIPs = 10.0.0.11/32

Nmap scan when wg0 is down:

Starting Nmap 7.93 ( https://nmap.org ) at 2024-08-16 03:26 CDT
Host is up (0.050s latency).
Not shown: 998 closed tcp ports (conn-refused)
PORT    STATE    SERVICE
22/tcp  open     ssh
179/tcp filtered bgp

Nmap done: 1 IP address (1 host up) scanned in 1.93 seconds

Nmap scan when wg0 is up:

Starting Nmap 7.93 ( https://nmap.org ) at 2024-08-16 03:27 CDT
All 1000 scanned ports are in ignored states.
Not shown: 1000 filtered tcp ports (no-response)

Nmap done: 1 IP address (1 host up) scanned in 201.43 seconds

I also cannot connect to host via ssh. How to fix this issue?

Upd. Fixed my changing server WireGuard IP to 10.0.1.1. 10.0.0.1 was already taken

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 0 points 1 month ago* (last edited 1 month ago) (1 children)

That's exactly what it does. Easy to see if OP new how to read their route tables.

Here's another: https://serverfault.com/questions/1102455/wireguard-policy-based-routing

[–] [email protected] 1 points 1 month ago (1 children)

What are you trying to say? That reply also shows AllowedIPs set to a /32 on the server side.

[–] [email protected] 0 points 1 month ago (2 children)

For Peers. There's no other route in OPs post. Like they said, when wg0 goes up, he can't reach anything else. All that happens is this interface comes out, changes the routing tables and forwarding, but doesn't go anywhere. It needs to be routed to the existing default gateway of the host. All this does is blackhole to the wg0 interface.

[–] atzanteol 1 points 1 month ago (1 children)

What "other route" are you expecting to see? My configuration looks very similar to OPs though I have an extra iptables entry in PostUp:

PostUp   = iptables -A FORWARD -i wg0 -j ACCEPT; iptables -A FORWARD -o wg0 -j ACCEPT; iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE; iptables -t nat -A POSTROUTING -o wg0 -j MASQUERADE

Is that what you mean?

[–] [email protected] 2 points 1 month ago* (last edited 1 month ago)

Thanks for help. Everything is fixed, read post update

[–] [email protected] 1 points 1 month ago (1 children)

Like I said in another thread on this post, I'm pretty sure that's because they are forwarding input but not output in the PostUp rules. Setting a /32 in AllowedIPs works fine for me.

[–] [email protected] 2 points 1 month ago* (last edited 1 month ago) (1 children)

Thanks for help. Everything is fixed, read post update

[–] [email protected] 1 points 1 month ago (1 children)

Oh yeah, can't use the same IP range as your LAN, that will lead to problems. :D Glad it's fixed.

Out of curiosity, does forwarding work now without the output (-o) command in PostUp?

[–] [email protected] 1 points 1 month ago

I left PostUp as is and didn't try removing -o))