Overview | Package | Class | Use | Tree | Deprecated | Index | Help
PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD

## org.apache.poi.poifs.crypt
Class Decryptor

    java.lang.Object
      org.apache.poi.poifs.crypt.Decryptor

All Implemented Interfaces:
  java.lang.Cloneable

Direct Known Subclasses:
  AgileDecryptor, BinaryRC4Decryptor, CryptoAPIDecryptor, StandardDecryptor, XORDecryptor

    public abstract class Decryptor

extends java.lang.Object
implements java.lang.Cloneable

Field Summary
`static java.lang.String` | `DEFAULT_PASSWORD`
`static java.lang.String` | `DEFAULT_POIFS_ENTRY`
`protected EncryptionInfo` | `encryptionInfo`

Constructor Summary
`protected` | `Decryptor()`

Method Summary
`Decryptor` | `clone()`
`protected int` | `getBlockSizeInBytes()`
`abstract java.io.InputStream` | `getDataStream(DirectoryNode dir)` Return a stream with decrypted data.
`java.io.InputStream` | `getDataStream(java.io.InputStream stream, int size, int initialPos)` Wraps a stream for decryption
`java.io.InputStream` | `getDataStream(NPOIFSFileSystem fs)`
`java.io.InputStream` | `getDataStream(OPOIFSFileSystem fs)`
`java.io.InputStream` | `getDataStream(POIFSFileSystem fs)`
`EncryptionInfo` | `getEncryptionInfo()`
`static Decryptor` | `getInstance(EncryptionInfo info)`
`byte[]` | `getIntegrityHmacKey()`
`byte[]` | `getIntegrityHmacValue()`
`protected int` | `getKeySizeInBytes()`
`abstract long` | `getLength()` Returns the length of the encrypted data that can be safely read with `getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode)`.
`javax.crypto.SecretKey` | `getSecretKey()`
`byte[]` | `getVerifier()`
`javax.crypto.Cipher` | `initCipherForBlock(javax.crypto.Cipher cipher, int block)` Initializes a cipher object for a given block index for encryption
`void` | `setChunkSize(int chunkSize)` Sets the chunk size of the data stream.
`void` | `setEncryptionInfo(EncryptionInfo encryptionInfo)`
`protected void` | `setIntegrityHmacKey(byte[] integrityHmacKey)`
`protected void` | `setIntegrityHmacValue(byte[] integrityHmacValue)`
`protected void` | `setSecretKey(javax.crypto.SecretKey secretKey)`
`protected void` | `setVerifier(byte[] verifier)`
`abstract boolean` | `verifyPassword(java.lang.String password)`

Methods inherited from class java.lang.Object
`equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### DEFAULT_PASSWORD

    public static final java.lang.String DEFAULT_PASSWORD

See Also:
  Constant Field Values

### DEFAULT_POIFS_ENTRY

    public static final java.lang.String DEFAULT_POIFS_ENTRY

See Also:
  Constant Field Values

### encryptionInfo

    protected EncryptionInfo encryptionInfo

Constructor Detail

### Decryptor

    protected Decryptor()

Method Detail

### getDataStream

    public abstract java.io.InputStream getDataStream(DirectoryNode dir)
                                               throws java.io.IOException,
                                                      java.security.GeneralSecurityException

  Return a stream with decrypted data.

  Use `getLength()` to get the size of that data that can be safely read from the stream. Just reading to the end of the input stream is not sufficient because there are normally padding bytes that must be discarded

  Parameters:
    `dir` - the node to read from
  Returns:
    decrypted stream
  Throws:
    `java.io.IOException`
    `java.security.GeneralSecurityException`

### getDataStream

    public java.io.InputStream getDataStream(java.io.InputStream stream,
                                             int size,
                                             int initialPos)
                                      throws java.io.IOException,
                                             java.security.GeneralSecurityException

  Wraps a stream for decryption

  As we are handling streams and don't know the total length beforehand, it's the callers duty to care for the length of the entries.

  Parameters:
    `stream` - the stream to be wrapped
    `initialPos` - initial/current byte position within the stream
  Returns:
    decrypted stream
  Throws:
    `java.io.IOException`
    `java.security.GeneralSecurityException`

### setChunkSize

    public void setChunkSize(int chunkSize)

  Sets the chunk size of the data stream. Needs to be set before the data stream is requested. When not set, the implementation uses method specific default values

  Parameters:
    `chunkSize` - the chunk size, i.e. the block size with the same encryption key

### initCipherForBlock

    public javax.crypto.Cipher initCipherForBlock(javax.crypto.Cipher cipher,
                                                  int block)
                                           throws java.security.GeneralSecurityException

  Initializes a cipher object for a given block index for encryption

  Parameters:
    `cipher` - may be null, otherwise the given instance is reset to the new block index
    `block` - the block index, e.g. the persist/slide id (hslf)
  Returns:
    a new cipher object, if cipher was null, otherwise the reinitialized cipher
  Throws:
    `java.security.GeneralSecurityException`

### verifyPassword

    public abstract boolean verifyPassword(java.lang.String password)
                                    throws java.security.GeneralSecurityException

  Throws:
    `java.security.GeneralSecurityException`

### getLength

    public abstract long getLength()

  Returns the length of the encrypted data that can be safely read with `getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode)`. Just reading to the end of the input stream is not sufficient because there are normally padding bytes that must be discarded

  The length variable is initialized in `getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode)`, an attempt to call getLength() prior to getDataStream() will result in IllegalStateException.

  Returns:
    length of the encrypted data
  Throws:
    `java.lang.IllegalStateException` - if `getDataStream(org.apache.poi.poifs.filesystem.DirectoryNode)` was not called

### getInstance

    public static Decryptor getInstance(EncryptionInfo info)

### getDataStream

    public java.io.InputStream getDataStream(NPOIFSFileSystem fs)
                                      throws java.io.IOException,
                                             java.security.GeneralSecurityException

  Throws:
    `java.io.IOException`
    `java.security.GeneralSecurityException`

### getDataStream

    public java.io.InputStream getDataStream(OPOIFSFileSystem fs)
                                      throws java.io.IOException,
                                             java.security.GeneralSecurityException

  Throws:
    `java.io.IOException`
    `java.security.GeneralSecurityException`

### getDataStream

    public java.io.InputStream getDataStream(POIFSFileSystem fs)
                                      throws java.io.IOException,
                                             java.security.GeneralSecurityException

  Throws:
    `java.io.IOException`
    `java.security.GeneralSecurityException`

### getVerifier

    public byte[] getVerifier()

### getSecretKey

    public javax.crypto.SecretKey getSecretKey()

### getIntegrityHmacKey

    public byte[] getIntegrityHmacKey()

### getIntegrityHmacValue

    public byte[] getIntegrityHmacValue()

### setSecretKey

    protected void setSecretKey(javax.crypto.SecretKey secretKey)

### setVerifier

    protected void setVerifier(byte[] verifier)

### setIntegrityHmacKey

    protected void setIntegrityHmacKey(byte[] integrityHmacKey)

### setIntegrityHmacValue

    protected void setIntegrityHmacValue(byte[] integrityHmacValue)

### getBlockSizeInBytes

    protected int getBlockSizeInBytes()

### getKeySizeInBytes

    protected int getKeySizeInBytes()

### getEncryptionInfo

    public EncryptionInfo getEncryptionInfo()

### setEncryptionInfo

    public void setEncryptionInfo(EncryptionInfo encryptionInfo)

### clone

    public Decryptor clone()
                    throws java.lang.CloneNotSupportedException

  Overrides:
    `clone` in class `java.lang.Object`
  Throws:
    `java.lang.CloneNotSupportedException`

Overview | Package | Class | Use | Tree | Deprecated | Index | Help
PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD

Copyright 2017 The Apache Software Foundation or its licensors, as applicable.