Package org.apache.commons.compress.archivers.zip

Class PKWareExtraHeader

java.lang.Object

org.apache.commons.compress.archivers.zip.PKWareExtraHeader

All Implemented Interfaces:

ZipExtraField

Direct Known Subclasses:

X0014_X509Certificates, X0015_CertificateIdForFile, X0016_CertificateIdForCentralDirectory, X0017_StrongEncryptionHeader, X0019_EncryptionRecipientCertificateList

public abstract class PKWareExtraHeader
extends Object
implements ZipExtraField

Base class for all PKWare strong crypto extra headers.

This base class acts as a marker so you know you can ignore all extra fields that extend this class if you are not interested in the meta data of PKWare strong encryption.

Algorithm IDs - integer identifier of the encryption algorithm from the following range

• 0x6601 - DES
• 0x6602 - RC2 (version needed to extract < 5.2)
• 0x6603 - 3DES 168
• 0x6609 - 3DES 112
• 0x660E - AES 128
• 0x660F - AES 192
• 0x6610 - AES 256
• 0x6702 - RC2 (version needed to extract >= 5.2)
• 0x6720 - Blowfish
• 0x6721 - Twofish
• 0x6801 - RC4
• 0xFFFF - Unknown algorithm

Hash Algorithms - integer identifier of the hash algorithm from the following range

• 0x0000 - none
• 0x0001 - CRC32
• 0x8003 - MD5
• 0x8004 - SHA1
• 0x8007 - RIPEMD160
• 0x800C - SHA256
• 0x800D - SHA384
• 0x800E - SHA512

Since:

1.11

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	PKWareExtraHeader.EncryptionAlgorithm	Encryption algorithm.
static enum	PKWareExtraHeader.HashAlgorithm	Hash Algorithm

Field Summary

Fields inherited from interface org.apache.commons.compress.archivers.zip.ZipExtraField

EXTRAFIELD_HEADER_SIZE

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PKWareExtraHeader(ZipShort headerId)

Method Summary

Modifier and Type	Method	Description
protected final void	assertMinimalLength(int minimum, int length)
byte[]	getCentralDirectoryData()	Gets the central data.
ZipShort	getCentralDirectoryLength()	Gets the central data length.
ZipShort	getHeaderId()	Gets the header id.
byte[]	getLocalFileDataData()	Gets the local data.
ZipShort	getLocalFileDataLength()	Gets the length of the local data.
void	parseFromCentralDirectoryData(byte[] data, int offset, int length)	Populate data from this array as if it was in central directory data.
void	parseFromLocalFileData(byte[] data, int offset, int length)	Populate data from this array as if it was in local file data.
void	setCentralDirectoryData(byte[] data)	Sets the extra field data in central directory.
void	setLocalFileDataData(byte[] data)	Sets the extra field data in the local file data - without Header-ID or length specifier.

Methods inherited from class java.lang.Object

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

Constructor Details

PKWareExtraHeader

protected PKWareExtraHeader(ZipShort headerId)

Method Details

assertMinimalLength

protected final void assertMinimalLength(int minimum,
 int length)
                                  throws ZipException

Throws:

ZipException

getCentralDirectoryData

public byte[] getCentralDirectoryData()

Gets the central data.

Specified by:

getCentralDirectoryData in interface ZipExtraField

Returns:

the central data if present, else return the local file data

getCentralDirectoryLength

public ZipShort getCentralDirectoryLength()

Gets the central data length. If there is no central data, get the local file data length.

Specified by:

getCentralDirectoryLength in interface ZipExtraField

Returns:

the central data length

getHeaderId

public ZipShort getHeaderId()

Gets the header id.

Specified by:

getHeaderId in interface ZipExtraField

Returns:

the header id

getLocalFileDataData

public byte[] getLocalFileDataData()

Gets the local data.

Specified by:

getLocalFileDataData in interface ZipExtraField

Returns:

the local data

getLocalFileDataLength

public ZipShort getLocalFileDataLength()

Gets the length of the local data.

Specified by:

getLocalFileDataLength in interface ZipExtraField

Returns:

the length of the local data

parseFromCentralDirectoryData

public void parseFromCentralDirectoryData(byte[] data,
 int offset,
 int length)
                                   throws ZipException

Description copied from interface: ZipExtraField

Populate data from this array as if it was in central directory data.

Specified by:

parseFromCentralDirectoryData in interface ZipExtraField

Parameters:

data - the array of bytes.

offset - the source location in the data array.

length - the number of bytes to use in the data array.

Throws:

ZipException - on error

See Also:

• ZipExtraField.parseFromCentralDirectoryData(byte[], int, int)

parseFromLocalFileData

public void parseFromLocalFileData(byte[] data,
 int offset,
 int length)
                            throws ZipException

Description copied from interface: ZipExtraField

Populate data from this array as if it was in local file data.

Specified by:

parseFromLocalFileData in interface ZipExtraField

Parameters:

data - the array of bytes.

offset - the source location in the data array.

length - the number of bytes to use in the data array.

Throws:

ZipException - on error

See Also:

• ZipExtraField.parseFromLocalFileData(byte[], int, int)

setCentralDirectoryData

public void setCentralDirectoryData(byte[] data)

Sets the extra field data in central directory.

Parameters:

data - the data to use

setLocalFileDataData

public void setLocalFileDataData(byte[] data)

Sets the extra field data in the local file data - without Header-ID or length specifier.

Parameters:

data - the field data to use