derive access key to smtp secret v4

smtp.rb

require 'openssl'
require 'base64'

def aws_iam_smtp_password_generator(key, region)
      # The values of the following variables should always stay the same.
      date = "11111111"
      service = "ses"
      terminal = "aws4_request"
      message = "SendRawEmail"
      version_in_bytes = "\x04"

      k_date = OpenSSL::HMAC.digest('sha256', "AWS4" + key, date)
      k_region = OpenSSL::HMAC.digest('sha256', k_date, region)
      k_service = OpenSSL::HMAC.digest('sha256', k_region, service)
      k_terminal = OpenSSL::HMAC.digest('sha256', k_service, terminal)
      k_message = OpenSSL::HMAC.digest('sha256', k_terminal, message)
      signature_and_version = version_in_bytes + k_message
      smtp_password = Base64.encode64(signature_and_version)

      smtp_password.to_s.strip
end


print aws_iam_smtp_password_generator('<YOUR_IAM_SECRET_HERE>', "<YOUR_AWS_REGION_HERE>")