Package net.shibboleth.shared.codec

Class Base64Support

java.lang.Object
net.shibboleth.shared.codec.Base64Support
public final class Base64Support extends Object
Helper class for working with Base64.

This helper class specifically addresses that waste of the Apache Codec encode/decode static methods creating new instances of the Base64 for every operation. It also provides the helper method to produce both chunked and unchunked encoded content as strings.

Most importantly this insulates calling code so we can swap in a different Base64 implementation, as commons-codec and many if not most others have a very inconvenient stance on whitespace, which is absolutely necessary to ignore, so changes to the implementation are likely to continue.

As of 9.3, a new system property has been introduced (SANITIZE_WHITESPACE_PROPERTY_NAME) to enable compatibility with newer commons-codec versions being used under this library at the cost of a whitespace removal scan. We do not support use of the library with that version, but the property provides a workaround for that case without incurring additional overhead for the project's own use. A future major update may obviate the need for that workaround.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final boolean
    CHUNKED
    Chunk the encoded data into 76-character lines broken by CRLF characters.
    private static final org.apache.commons.codec.binary.Base64
    CHUNKED_ENCODER
    Encoder used to produce chunked output.
    static final boolean
    sanitize
    Triggers whitespace sanitization of input when decoding, per JSSH-84.
    static final String
    SANITIZE_WHITESPACE_PROPERTY_NAME
    System property name to enable whitespace sanitization on decode for commons-codec 1.23 compatibility.
    static final boolean
    UNCHUNKED
    Do not chunk encoded data.
    private static final org.apache.commons.codec.binary.Base64
    UNCHUNKED_ENCODER
    Encoder used to produce unchunked output.

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    Base64Support()
    Constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    static byte[]
    decode(String data)
    Decodes (un)chunked Base64 encoded data.
    static byte[]
    decodeURLSafe(String data)
    Decodes (un)chunked Base64URL encoded data.
    static String
    encode(byte[] data, boolean chunked)
    Base64 encodes the given binary data.
    static String
    encodeURLSafe(byte[] data)
    Base64URL encodes the given binary data.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • SANITIZE_WHITESPACE_PROPERTY_NAME

      @Nonnull @NotEmpty public static final String SANITIZE_WHITESPACE_PROPERTY_NAME
      System property name to enable whitespace sanitization on decode for commons-codec 1.23 compatibility.
      See Also:

    • CHUNKED

      public static final boolean CHUNKED
      Chunk the encoded data into 76-character lines broken by CRLF characters.
      See Also:

    • UNCHUNKED

      public static final boolean UNCHUNKED
      Do not chunk encoded data.
      See Also:

    • sanitize

      public static final boolean sanitize
      Triggers whitespace sanitization of input when decoding, per JSSH-84.

    • CHUNKED_ENCODER

      @Nonnull private static final org.apache.commons.codec.binary.Base64 CHUNKED_ENCODER
      Encoder used to produce chunked output.

    • UNCHUNKED_ENCODER

      @Nonnull private static final org.apache.commons.codec.binary.Base64 UNCHUNKED_ENCODER
      Encoder used to produce unchunked output.

  • Constructor Details

    • Base64Support

      private Base64Support()
      Constructor.

  • Method Details

    • encode

      @Nonnull public static String encode(@Nonnull byte[] data, boolean chunked) throws EncodingException
      Base64 encodes the given binary data.
      Parameters:
      data - data to encode
      chunked - whether the encoded data should be chunked or not
      Returns:
      the base64 encoded data
      Throws:
      EncodingException - when any Exception is thrown from the underlying encoder, or the output is null.

    • decode

      @Nonnull public static byte[] decode(@Nonnull String data) throws DecodingException
      Decodes (un)chunked Base64 encoded data.
      Parameters:
      data - Base64 encoded data
      Returns:
      the decoded data
      Throws:
      DecodingException - when any Exception is thrown from the underlying decoder, or the output is null.

    • encodeURLSafe

      @Nonnull public static String encodeURLSafe(@Nonnull byte[] data) throws EncodingException
      Base64URL encodes the given binary data.

      This is compliant with RFC 4648, Section 5: "Base 64 Encoding with URL and Filename Safe Alphabet".

      Parameters:
      data - data to encode
      Returns:
      the base64url encoded data
      Throws:
      EncodingException - if the input data can not be encoded as a base64 string.

    • decodeURLSafe

      @Nonnull public static byte[] decodeURLSafe(@Nonnull String data) throws DecodingException
      Decodes (un)chunked Base64URL encoded data.

      This is compliant with RFC 4648, Section 5: "Base 64 Encoding with URL and Filename Safe Alphabet".

      Parameters:
      data - Base64URL encoded data
      Returns:
      the decoded data
      Throws:
      DecodingException - if unable to decode the input data.