}
	// Set the body to generate signature mismatch.
	helloReader := bytes.NewReader([]byte("Hello, World"))
	request.ContentLength = helloReader.Size()
	request.Body = io.NopCloser(helloReader)
	c.Assert(err, nil)

	// execute the HTTP request.
	response, err = s.client.Do(request)
	c.Assert(err, nil)
	if s.signer == signerV4 {