aws-get-ip-for-region.sh

#!/bin/bash

################################################################
# This is a script that pulls a list of IPs from AWS
# published IP list, then parses it looking for a 
# specific region and service.
#
# Dependencies:
# This script needs:
#   * Internet access
#   * ./jq installed. jq is a lightweight and flexible 
#     command-line JSON processor. Available for multiple 
#     platforms via the public website: 
#     https://stedolan.github.io/jq/download/
#
# Usage:
# Run the script with no arguments to get syntax.
#
# Release Notes:
#   * 2020-01-07 [email protected] - Initial creation.
#
################################################################

# Helper Functions

# Prints the syntax of the command
print-syntax() {
  echo ""
  echo "Syntax: $0 [aws-region-code] [aws-service-code]"
  echo "Valid values: "
  echo "  aws-region-code: ap-east-1 | ap-northeast-1 | ap-northeast-2 | ap-northeast-3 | ap-south-1 | ap-southeast-1 | ap-southeast-2 | ca-central-1 | cn-north-1 | cn-northwest-1 | eu-central-1 | eu-north-1 | eu-west-1 | eu-west-2 | eu-west-3 | me-south-1 | sa-east-1 | us-east-1 | us-east-2 | us-gov-east-1 | us-gov-west-1 | us-west-1 | us-west-2 | GLOBAL"
  echo "  aws-service-code: AMAZON | AMAZON_CONNECT | API_GATEWAY | CLOUD9 | CLOUDFRONT | CODEBUILD | DYNAMODB | EC2 | EC2_INSTANCE_CONNECT | GLOBALACCELERATOR | ROUTE53 | ROUTE53_HEALTHCHECKS | S3"
  echo "All parameters are case-sensitive."
}

# Output the tool's banner.
echo ""
echo "AWS IP Address Fetch Tool by [email protected]"

# Sanity - we need the region!
if [ -z "$1" ] || [ -z "$2" ]; then
  print-syntax
  exit
fi

# Set useful variables
AWS_REGION_CODE=$1
AWS_SERVICE_CODE=$2
IP_LOCAL_FILE=ip-ranges.json
CURRENT_PATH=$(pwd)
TIMESTAMP=$(date)

# Pull the current list from AWS using CURL
echo "Retrieving list of IPs from AWS into \"${CURRENT_PATH}/${IP_LOCAL_FILE}\""
curl --silent --output "${CURRENT_PATH}/${IP_LOCAL_FILE}" https://ip-ranges.amazonaws.com/ip-ranges.json

# Extract just the info we need, IP for the passed in region using the jq parser
echo "As of ${TIMESTAMP}, the IP Ranges for the region: \"$AWS_REGION_CODE\" and service: \"$AWS_SERVICE_CODE\" are:"
jq -r ".prefixes[] | select(.region==\"${AWS_REGION_CODE}\" and .service==\"${AWS_SERVICE_CODE}\") | .ip_prefix" < ${CURRENT_PATH}/${IP_LOCAL_FILE}