func doesPresignedSignatureMatch(hashedPayload string, r *http.Request, region string, stype serviceType) APIErrorCode {
	// Copy request
	req := *r

	// Parse request query string.
	pSignValues, err := parsePreSignV4(req.Form, region, stype)
	if err != ErrNone {
		return err
	}

	cred, _, s3Err := checkKeyValid(r, pSignValues.Credential.accessKey)
	if s3Err != ErrNone {
		return s3Err
	}