var rawStdEncoding = StdEncoding.WithPadding(NoPadding)
	type test struct {
		enc  *Encoding
		n    int
		want int64
	}
	tests := []test{
		{StdEncoding, 0, 0},
		{StdEncoding, 1, 8},
		{StdEncoding, 2, 8},
		{StdEncoding, 3, 8},
		{StdEncoding, 4, 8},
		{StdEncoding, 5, 8},
		{StdEncoding, 6, 16},
		{StdEncoding, 10, 16},
		{StdEncoding, 11, 24},
		{rawStdEncoding, 0, 0},

			MetaIV: base64.StdEncoding.EncodeToString(append([]byte{1}, make([]byte, 31)...)), MetaAlgorithm: SealAlgorithm,
			MetaSealedKeyS3: base64.StdEncoding.EncodeToString(append([]byte{1}, make([]byte, 63)...)), MetaKeyID: "key-1",
			MetaDataEncryptionKey: base64.StdEncoding.EncodeToString(make([]byte, 48)),
		},
		DataKey: make([]byte, 48), KeyID: "key-1", SealedKey: SealedKey{Algorithm: SealAlgorithm, Key: [64]byte{1}, IV: [32]byte{1}},

		return ChecksumMismatch{
			Want: fmt.Sprintf("%s-%d", c.Encoded, c.WantParts),
			Got:  fmt.Sprintf("%s-%d", base64.StdEncoding.EncodeToString(sum), parts),
		}
	}

	if !bytes.Equal(sum, c.Raw) {
		return ChecksumMismatch{
			Want: c.Encoded,
			Got:  base64.StdEncoding.EncodeToString(sum),
		}
	}
	return nil
}

// AsMap returns the
func (c *Checksum) AsMap() map[string]string {

	// 2-byte footer.
	maxContentLen = maxEncodedWordLen - len("=?UTF-8?q?") - len("?=")
)

var maxBase64Len = base64.StdEncoding.DecodedLen(maxContentLen)

// bEncode encodes s using base64 encoding and writes it to buf.
func (e WordEncoder) bEncode(buf *strings.Builder, charset, s string) {
	w := base64.NewEncoder(base64.StdEncoding, buf)
	// If the charset is not UTF-8 or if the content is short, do not bother
	// splitting the encoded-word.

	// as Base64 encoding of a value is not unique:
	// For example "aGVsbG8=" and "aGVsbG8=\r" will result in the same byte slice.
	signature1, err := base64.StdEncoding.DecodeString(sig1)
	if err != nil {
		return false
	}
	signature2, err := base64.StdEncoding.DecodeString(sig2)
	if err != nil {
		return false
	}
	return subtle.ConstantTimeCompare(signature1, signature2) == 1
}

// Return canonical headers.

	if *requireAnyClientCertificate {
		cfg.ClientAuth = RequireAnyClientCert
	}
	if *verifyPeer {
		cfg.ClientAuth = VerifyClientCertIfGiven
	}

	if *echConfigListB64 != "" {
		echConfigList, err := base64.StdEncoding.DecodeString(*echConfigListB64)
		if err != nil {
			log.Fatalf("parse ech-config-list err: %s", err)
		}
		cfg.EncryptedClientHelloConfigList = echConfigList
		cfg.MinVersion = VersionTLS13
	}

	{"Basic " + base64.StdEncoding.EncodeToString([]byte(":")), "", "", true},
	{"Basic" + base64.StdEncoding.EncodeToString([]byte("Aladdin:open sesame")), "", "", false},
	{base64.StdEncoding.EncodeToString([]byte("Aladdin:open sesame")), "", "", false},
	{"Basic ", "", "", false},
	{"Basic Aladdin:open sesame", "", "", false},
	{`Digest username="Aladdin"`, "", "", false},

		frame[0] = num
		copy(frame[1:], data)
		if err := websocket.Message.Send(conn.ws, frame); err != nil {
			return 0, err
		}
	case base64Codec:
		frame := string('0'+num) + base64.StdEncoding.EncodeToString(data)
		if err := websocket.Message.Send(conn.ws, frame); err != nil {
			return 0, err
		}
	}
	return len(data), nil
}

// websocketChannel represents a channel in a connection

		case e.decodeMap[encoder[i]] != invalidIndex:
			panic("encoding alphabet includes duplicate symbols")
		}
		e.decodeMap[encoder[i]] = uint8(i)
	}
	return e
}

// StdEncoding is the standard base32 encoding, as defined in RFC 4648.
var StdEncoding = NewEncoding("ABCDEFGHIJKLMNOPQRSTUVWXYZ234567")

// HexEncoding is the “Extended Hex Alphabet” defined in RFC 4648.
// It is typically used in DNS.

			}
			return x509.ParseCertificate(block.Bytes)
		}
		block = nextBlock
	}
}

func x509CertSignature(cert *x509.Certificate) string {
	return base64.StdEncoding.EncodeToString(cert.Signature)
}

func certFileSignature(certFile, keyFile string) (string, error) {
	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
	if err != nil {
		return "", err
	}