Add a public IP to an AWS security group and schedule automatic removal

register-ip-with-ec2.sh

#!/usr/bin/env bash

# You need to set some vars somewhere:
# SECURTITY_GROUP=<your_security_group_id>
# on mac you need to enable running the `at` command:
# $ sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.atrun.plist

current_ip=$(curl -s http://checkip.amazonaws.com/)

echo "Current IP: ${current_ip}"

current_ip="${current_ip}/32"
for existing_ip in $(aws ec2 describe-security-groups --group-ids $SECURITY_GROUP | jq -r '.SecurityGroups[0].IpPermissions[1].IpRanges[] | .CidrIp'); do
    if [[ $existing_ip == "$current_ip" ]]; then
        echo "IP already registered, bailing"
        exit
    fi
done

echo "What location are you at?"
read location_description

echo "IP: $current_ip; LOCATION: $location_description" >> ~/.aws_added_ips

echo "IP doesn't exist, adding as ${current_ip}"
aws ec2 authorize-security-group-ingress --group-id $SECURITY_GROUP --protocol tcp --port 22 --cidr $current_ip

echo "Scheduling removal at 5:00pm"

at 5:00 PM <<COMMAND
aws ec2 revoke-security-group-ingress --group-id $SECURITY_GROUP --protocol tcp --port 22 --cidr $current_ip
COMMAND