AWS::EC2::NetworkAclEntry:
  Properties:
    CidrBlock: "\"172.16.0.0/24\""
    Egress: "\"true|false\""
    Icmp: |
      { "Code" => "-1|Integer", "Type" => "-1|Integer|http://www.iana.org/assignments/icmp-parameters/icmp-parameters.xhtml"}
    NetworkAclId: "\"String\""
    PortRange: |
      { "From" => "Integer", "To" => "Integer" }
    Protocol: "\"http://www.iana.org/assignments/protocol-numbers/protocol-numbers.xhtml\""
    RuleAction: "\"allow|deny\""
    RuleNumber: 100