Wireguard Multiline Config Value

Question

Is it possible to split a config command over multiple lines instead of one long string?

E.g.

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

When using more commands the line gets very long and unreadable. I would like to split it so that I can use one line per command. Something like:

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

The man page says it's based on the ini format but has no help on this topic.

try it and see. did it work? you have your answer. did it not work? you also have your answer. — cas, May 31 '21 at 04:17
@cas your answer does not make sense. My example was to show what I am looking for. If I knew the correct format I would not have asked. — laktak, May 31 '21 at 09:08
@A.B are you implying it works for you? It's a made up example. No it does not work for me. — laktak, May 31 '21 at 09:12
@A.B I really thought that was clear. I'll keep it in mind next time. — laktak, May 31 '21 at 21:58

A.B · Accepted Answer · 2021-06-01T00:16:14.020

The wg-quick command is a bash script. The loop reading keys (such as the PostUp key) is using read -r which prevents any use of \ to separate lines. But reading this same script shows:

POST_UP=( )

to declare it as an array, and:

          PostUp) POST_UP+=( "$value" ); continue ;;

to add an element to the array.

It's then executed later with (there's an eval command in the function execute_hooks):

execute_hooks "${POST_UP[@]}"

Thus one can split multiple commands (but not arbitrary lines) by using multiple times the same key entry. So OP's example would work like this:

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

Actually the man page already tells it:

• PreUp, PostUp, PreDown, PostDown — script snippets which will be executed by bash(1) before/after setting up/tearing down the interface, most commonly used to configure custom DNS options or firewall rules. The special string `%i' is expanded to INTERFACE. Each one may be specified multiple times, in which case the commands are executed in order.

Wireguard Multiline Config Value

1 Answers1