}
	return authTypeUnknown
}

func validateAdminSignature(ctx context.Context, r *http.Request, region string) (auth.Credentials, bool, APIErrorCode) {
	var cred auth.Credentials
	var owner bool
	s3Err := ErrAccessDenied
	if _, ok := r.Header[xhttp.AmzContentSha256]; ok &&
		getRequestAuthType(r) == authTypeSigned {

		// Get credential information from the request.
		cred, owner, s3Err = getReqAccessKeyV4(r, region, serviceS3)

			ConditionValues: getConditionValues(r, "", cred),
			IsOwner:         owner,
			Claims:          cred.Claims,
		}) {
			writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAccessDenied), r.URL)
			return
		}
	} else {
		if !globalIAMSys.IsAllowed(policy.Args{
			AccountName:     cred.AccessKey,
			Groups:          cred.Groups,
			Action:          policy.ListServiceAccountsAdminAction,

		ConditionValues: getConditionValues(r, "", cred),
		IsOwner:         owner,
		Claims:          cred.Claims,
		DenyOnly:        checkDenyOnly,
	}) {
		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAccessDenied), r.URL)
		return
	}

	userInfo, err := globalIAMSys.GetUserInfo(ctx, name)
	if err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	if s3Error != ErrNone && s3Error != ErrAccessDenied {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
		return
	}

	// Anonymous users, should be rejected.
	if cred.AccessKey == "" {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrAccessDenied), r.URL)
		return
	}

	// If etcd, dns federation configured list buckets from etcd.

//go:generate stringer -type=APIErrorCode -trimprefix=Err $GOFILE

// Error codes, non exhaustive list - http://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html
const (
	ErrNone APIErrorCode = iota
	ErrAccessDenied
	ErrBadDigest
	ErrEntityTooSmall
	ErrEntityTooLarge
	ErrPolicyTooLarge
	ErrIncompleteBody
	ErrInternalError
	ErrInvalidAccessKeyID
	ErrAccessKeyDisabled
	ErrInvalidArgument
	ErrInvalidBucketName

//
// The test works in 2 steps, here is the description of the steps.
//
//	STEP 1: Call the handler with the unsigned HTTP request (anonReq), assert for the `ErrAccessDenied` error response.
func ExecObjectLayerAPIAnonTest(t *testing.T, obj ObjectLayer, testName, bucketName, objectName, instanceType string, apiRouter http.Handler,
	anonReq *http.Request, bucketPolicy *policy.BucketPolicy,
) {

				if reader != nil && proxy.Proxy && perr == nil {
					gr = reader
				}
			}
		}
		if reader == nil || !proxy.Proxy {
			// validate if the request indeed was authorized, if it wasn't we need to return "ErrAccessDenied"
			// instead of any namespace related error.
			if s3Error := authorizeRequest(ctx, r, policy.GetObjectAction); s3Error != ErrNone {
				writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
				return