AWS::SQS::QueuePolicy:

Properties: 
  PolicyDocument: |
    {
      "Id"          => "MyQueuePolicy",
      "Version"     => "2012-10-17",
      "Statement"   => [ {
        "Sid"       => "Allow-User-SendMessage",
        "Effect"    => "Allow",
        "Principal" => {
          "AWS"     => "arn:aws:iam::123456789012:user/myapp"
        },
        "Action"    => [ "sqs:SendMessage" ],
        "Resource"  => "*"
        } ]
    }
  Queues: |
    [
      "The URLs of the queues to which you want to add the policy. You can use the Ref function to specify an AWS::SQS::Queue resource."
    ]