if payload != req.Header.Get(xhttp.AmzContentSha256) {
		return cred, "", "", time.Time{}, ErrContentSHA256Mismatch
	}

	// Extract all the signed headers along with its values.
	extractedSignedHeaders, errCode := extractSignedHeaders(signV4Values.SignedHeaders, r)
	if errCode != ErrNone {
		return cred, "", "", time.Time{}, errCode
	}

	cred, _, errCode = checkKeyValid(r, signV4Values.Credential.accessKey)
	if errCode != ErrNone {