func (e Error) Unwrap() error { return e.cause }

// Error 'error' compatible method.
func (e Error) Error() string {
	if e.msg == "" {
		return "crypto: cause <nil>"
	}
	return e.msg
}

var (
	// ErrInvalidEncryptionMethod indicates that the specified SSE encryption method
	// is not supported.
	ErrInvalidEncryptionMethod = Errorf("The encryption method is not supported")

	if err != nil {
		t.Fatal(err)
	}

	r := &http.Request{
		Proto:  "HTTP/1.0",
		Method: http.MethodPost,
		URL:    u,
	}
	if !guessIsRPCReq(r) {
		t.Fatal("Test shouldn't fail for a possible net/rpc request.")
	}
	r = &http.Request{
		Proto:  "HTTP/1.1",
		Method: http.MethodGet,
	}
	if guessIsRPCReq(r) {
		t.Fatal("Test shouldn't report as net/rpc for a non net/rpc request.")
	}

	return r.NoncurrentVersionTransition.Validate()
}

// GetPrefix - a rule can either have prefix under <rule></rule>, <filter></filter>
// or under <filter><and></and></filter>. This method returns the prefix from the
// location where it is available.
func (r Rule) GetPrefix() string {
	if p := r.Prefix.String(); p != "" {
		return p
	}
	if p := r.Filter.Prefix.String(); p != "" {
		return p

	if err != nil {
		return false
	}
	return mediaType == "multipart/form-data" && r.Method == http.MethodPost
}

// Verify if the request has AWS Streaming Signature Version '4'. This is only valid for 'PUT' operation.
func isRequestSignStreamingV4(r *http.Request) bool {
	return r.Header.Get(xhttp.AmzContentSha256) == streamingContentSHA256 &&
		r.Method == http.MethodPut
}

		Duration:  end.Sub(start),
		Path:      t.Subroute,
		Error:     errString,
		HTTP: &madmin.TraceHTTPStats{
			ReqInfo: madmin.TraceRequestInfo{
				Time:    start,
				Proto:   "grid",
				Method:  "REQ",
				Client:  local,
				Headers: nil,
				Path:    t.Subroute,
				Body:    []byte(body),
			},
			RespInfo: madmin.TraceResponseInfo{
				Time:       end,
				Headers:    nil,

	}

	// Test use case 2: Make 9 disks offline, which leaves less than quorum number of disks
	// in a 16 disk Erasure setup. The original disks are 'replaced' with
	// naughtyDisks that fail after 'f' successful StorageAPI method
	// invocations, where f - [0,2)

	// Create "object" under "bucket".
	_, err = obj.PutObject(ctx, bucket, object, mustGetPutObjReader(t, bytes.NewReader(buf), int64(len(buf)), "", ""), opts)
	if err != nil {

type SignatureDoesNotMatch struct{}

func (e SignatureDoesNotMatch) Error() string {
	return "The request signature we calculated does not match the signature you provided. Check your key and signing method."
}

// StorageFull storage ran out of space.
type StorageFull struct{}

func (e StorageFull) Error() string {
	return "Storage reached its minimum free drive threshold."
}

		Description:    "The request signature we calculated does not match the signature you provided. Check your key and signing method.",
		HTTPStatusCode: http.StatusForbidden,
	},
	ErrMethodNotAllowed: {
		Code:           "MethodNotAllowed",
		Description:    "The specified method is not allowed against this resource.",
		HTTPStatusCode: http.StatusMethodNotAllowed,
	},
	ErrInvalidPart: {

		}
	}
}

// Provides a fully populated http request instance, fails otherwise.
func mustNewRequest(method string, urlStr string, contentLength int64, body io.ReadSeeker, t *testing.T) *http.Request {
	req, err := newTestRequest(method, urlStr, contentLength, body)
	if err != nil {
		t.Fatalf("Unable to initialize new http request %s", err)
	}
	return req
}

func preSignatureV2(cred auth.Credentials, method string, encodedResource string, encodedQuery string, headers http.Header, expires string) string {
	stringToSign := getStringToSignV2(method, encodedResource, encodedQuery, headers, expires)
	return calculateSignatureV2(stringToSign, cred.SecretKey)
}

// Return the signature v2 of a given request.