ec2.rb

#
# Author:: Tim Dysinger (<tim@dysinger.net>)
# Author:: Benjamin Black (<bb@opscode.com>)
# Author:: Christopher Brown (<cb@opscode.com>)
# Copyright:: Copyright (c) 2009 Opscode, Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

require 'ohai/mixin/ec2_metadata'
require 'base64'

Ohai.plugin(:EC2) do
  include Ohai::Mixin::Ec2Metadata

  provides "ec2"

  depends "network/interfaces"

  def has_ec2_mac?
    network[:interfaces].values.each do |iface|
      unless iface[:arp].nil?
        if iface[:arp].value?("fe:ff:ff:ff:ff:ff")
          Ohai::Log.debug("has_ec2_mac? == true")
          return true
        end
      end
    end
    Ohai::Log.debug("has_ec2_mac? == false")
    false
  end

  def looks_like_ec2?
    # Try non-blocking connect so we don't "block" if
    # the Xen environment is *not* EC2
    hint?('ec2') || has_ec2_mac? && can_metadata_connect?(Ohai::Mixin::Ec2Metadata::EC2_METADATA_ADDR,80)
  end

  collect_data do
    if looks_like_ec2?
      Ohai::Log.debug("looks_like_ec2? == true")
      ec2 Mash.new
      fetch_metadata.each do |k, v|
        # fetch_metadata returns IAM security credentials, including the IAM user's
        # secret access key. We'd rather not have ohai send this information
        # to the server.
        # http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AESDG-chapter-instancedata.html#instancedata-data-categories
        next if k == 'iam' && !hint?('iam')
        ec2[k] = v
      end
      ec2[:userdata] = self.fetch_userdata
      #ASCII-8BIT is equivalent to BINARY in this case
      if ec2[:userdata].encoding.to_s == "ASCII-8BIT"
        Ohai::Log.debug("Binary UserData Found. Storing in base64")
        ec2[:userdata] = Base64.encode64(ec2[:userdata])
      end
    else
      Ohai::Log.debug("looks_like_ec2? == false")
      false
    end
  end
end