Field Detail

• charset

  protected final Charset charset

  The character set which has been provided to the constructor and is used for encoding entry names and the file comment in the ZIP file .

Constructor Detail

• KeyManagerZipCryptoParameters

  public KeyManagerZipCryptoParameters(ZipDriver driver,
                               FsModel model,
                               Charset charset)

  Constructs new ZIP crypto parameters.

  Parameters:

  driver - the ZIP driver.

  model - the file system model.

  charset - the character set which is used for encoding entry names and the file comment in the ZIP file.

Method Detail

• get

  public <P extends ZipParameters> P get(Class<P> type)

  Returns ZipParameters of the given type or null if not available.

  If type is assignable from WinZipAesParameters, then a KeyManager for AesPbeParameters will get used which is obtained from the provider which has been provided to the constructor.

  Otherwise, null gets returned.

  Specified by:

  get in interface ZipParametersProvider

  Parameters:

  type - the ZipParameters interface class which's implementation is required.

  Returns:

  ZipParameters of the given type or null if not available.

• password

  protected byte[] password(char[] characters,
                String name)

  A template method to derive password bytes from the given password characters and the given entry name. Typically, only the given password characters should get encoded to form the result. Optionally, the given entry name can be mixed into the result for authentication. Note that this would then form a part of the password used for writing or reading encrypted entries, however. A third party which is expected to successfully read or write encrypted entries would have to agree on the same password bytes derivation scheme.

  The implementation in the class KeyManagerZipCryptoParameters ignores the given entry name and just encodes the given password characters using PBEParametersGenerator.PKCS5PasswordToBytes(char[]).

  A reasonable alternative implementation could encode the given password characters using the value of the field charset, which is the character set actually used to encode entry names and comments in the ZIP file, e.g. UTF-8 or CP437.

  Parameters:

  characters - the password characters to encode.

  name - the entry name for optional mixing into the result.

  Returns:

  The derived password bytes.

  See Also:

  Discussion Of Alternative Character Set Encodings, RFC 2898: PKCS #5: Password-Based Cryptography Specification Version 2.0 (IETF et al.)