return ErrNone
}

// doesSignatureMatch - Verify authorization header with calculated header in accordance with
//   - http://docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-authenticating-requests.html
//
// returns ErrNone if signature matches.
func doesSignatureMatch(hashedPayload string, r *http.Request, region string, stype serviceType) APIErrorCode {
	// Copy request.

}

func reqSignatureV4Verify(r *http.Request, region string, stype serviceType) (s3Error APIErrorCode) {
	sha256sum := getContentSha256Cksum(r, stype)
	switch {
	case isRequestSignatureV4(r):
		return doesSignatureMatch(sha256sum, r, region, stype)
	case isRequestPresignedSignatureV4(r):
		return doesPresignedSignatureMatch(sha256sum, r, region, stype)
	default:
		return ErrAccessDenied
	}
}