How to add multiple interfaces to trusted zone using firewalld command?

Question

I am adding a particular interface as an trusted zone using below command

firewall-cmd --zone=trusted --change-interface=eth0

Now suppose I have multiple interfaces(like eth0, eth1, bond0, bond1) and I want to add all of them once, by executing the above command written in a bash script.

What will be the syntax and command for adding all the interfaces by executing above command once?

Answer 1

This will get all the device names and then proceed to run the command for every interface.

for i in $( ifconfig -a | sed 's/[ \t].*//;/^\(lo\|\)$/d' ); do
    firewall-cmd --zone=trusted --change-interface=$i
    echo "Added $i to trusted\n"
done

Answer 2

Assuming you are on a Linux system with the ip command (but not the busybox variant of it), we may ask it for the addr information in JSON format using ip -j addr.

From that result, we may use the JSON processor jq to extract the interface name and create shell code that we can evaluate:

eval "$(
    ip -j addr |
    jq -r 'map(
        ["firewall-cmd", "--zone=trusted", "--change-interface=" + .ifname],
        ["printf", "added %s to trusted\\n", .ifname] | @sh )[]'
)"

On an Ubuntu virtual machine I have, this would evaluate the following commands:

'firewall-cmd' '--zone=trusted' '--change-interface=lo'
'printf' 'added %s to trusted\n' 'lo'
'firewall-cmd' '--zone=trusted' '--change-interface=enp0s3'
'printf' 'added %s to trusted\n' 'enp0s3'
'firewall-cmd' '--zone=trusted' '--change-interface=enp0s8'
'printf' 'added %s to trusted\n' 'enp0s8'
'firewall-cmd' '--zone=trusted' '--change-interface=docker0'
'printf' 'added %s to trusted\n' 'docker0'

Or, we can make a more traditional shell loop that iterates over only the interface names:

ip -j addr | jq -r 'map(.ifname)[]' |
while IFS= read -r ifn; do
    firewall-cmd --zone=trusted --change-interface="$ifn"
    printf 'added %s to trusted\n' "$ifn"
done

Answer 3

This avoids the complex and unexplained sed syntax from the previous answer

devlist=`netstat -i |cut -f1 -d' '`
for dev in ${devlist}; do
  echo "Adding $dev to trusted"
  firewall-cmd --zone=trusted --change-interface=$dev
done