mirror of
https://gitea.blesmrt.net/mikaela/shell-things.git
synced 2024-11-22 19:29:22 +01:00
38 lines
1.1 KiB
Bash
Executable File
38 lines
1.1 KiB
Bash
Executable File
#!/usr/bin/env bash
|
|
set -x
|
|
|
|
# Require root or exit
|
|
if [ "$(id -u)" != "0" ]; then
|
|
echo "This script requires root. (And the 3 nameserver IPs as arguments)" 1>&2
|
|
exit 1
|
|
fi
|
|
|
|
# Three arguments or quit.
|
|
if [ $# -ne 3 ]; then
|
|
echo "This script requires three arguments that will be passed as nameservers."
|
|
exit 1
|
|
fi
|
|
|
|
# In case I am behind the /etc/resolv.conf, it's immutable and read-only,
|
|
# which won't allow it to be rewritten.
|
|
chattr -V -i /etc/resolv.conf
|
|
chmod -v +w /etc/resolv.conf
|
|
# Or it's a symlink to e.g. /run/systemd/resolve/stub-resolv.conf
|
|
rm -v /etc/resolv.conf
|
|
|
|
# No trust-ad here as chances are these resolvers are unencrypted and the
|
|
# path to them isn't trusted.
|
|
# tee -p = operate in a more appropriate MODE with pipes.
|
|
printf "nameserver %b\nnameserver %b\nnameserver %b\nsearch .\noptions timeout:2 attempts:2 rotate edns0\n" "$1" "$2" "$3" | tee -p /etc/resolv.conf
|
|
|
|
# Remove all other permissions than everyone reading resolv.conf
|
|
chmod -v a=r /etc/resolv.conf
|
|
# Make resolv.conf immutable again so it's pretty sure nothing else edits it.
|
|
chattr -V +i /etc/resolv.conf
|
|
|
|
# Let's just see it's ok
|
|
ls -l /etc/resolv.conf
|
|
cat /etc/resolv.conf
|
|
|
|
set +x
|