org.sejda.sambox.pdmodel.encryption

Class SecurityHandler

java.lang.Object

org.sejda.sambox.pdmodel.encryption.SecurityHandler

Direct Known Subclasses:

PublicKeySecurityHandler, StandardSecurityHandler

public abstract class SecurityHandler
extends Object

A security handler as described in the PDF specifications. A security handler is responsible of documents protection.

Author:

Ben Litchfield, Benoit Guillon, Manuel Kasper

Field Summary

Fields

Modifier and Type	Field and Description
protected int	keyLength The length of the secret key used to encrypt the document.

Constructor Summary

Constructors

Constructor and Description
SecurityHandler()

Method Summary

Modifier and Type	Method and Description
void	decrypt(COSBase obj, long objNum, long genNum) This will dispatch to the correct method.
protected void	decryptDataRC4(byte[] finalKey, byte[] input, OutputStream output) Encrypt or decrypt data with RC4.
protected void	decryptDataRC4(byte[] finalKey, InputStream input, OutputStream output) Encrypt or decrypt data with RC4.
void	decryptStream(COSStream stream, long objNum, long genNum) This will decrypt a stream.
AccessPermission	getCurrentAccessPermission() Returns the access permissions that were computed during document decryption.
byte[]	getEncryptionKey()
int	getKeyLength() Getter of the property keyLength.
abstract boolean	hasProtectionPolicy() Returns whether a protection policy has been set.
boolean	isAES() True if AES is used for encryption and decryption.
abstract void	prepareForDecryption(PDEncryption encryption, COSArray documentIDArray, DecryptionMaterial decryptionMaterial) Prepares everything to decrypt the document.
void	setAES(boolean aesValue) Set to true if AES for encryption and decryption should be used.
void	setCurrentAccessPermission(AccessPermission currentAccessPermission) Sets the access permissions.
protected void	setDecryptMetadata(boolean decryptMetadata) Set wether to decrypt meta data.
protected void	setEncryptionKey(byte[] encryptionKey)
void	setKeyLength(int keyLen) Setter of the property keyLength.
protected void	setStreamFilterName(COSName streamFilterName) Set the stream filter name.
protected void	setStringFilterName(COSName stringFilterName) Set the string filter name.

Methods inherited from class java.lang.Object

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

Field Detail

keyLength

protected int keyLength

The length of the secret key used to encrypt the document.

Constructor Detail

SecurityHandler

public SecurityHandler()

Method Detail

setDecryptMetadata

protected void setDecryptMetadata(boolean decryptMetadata)

Set wether to decrypt meta data.

Parameters:

decryptMetadata - true if meta data has to be decrypted.

setStringFilterName

protected void setStringFilterName(COSName stringFilterName)

Set the string filter name.

Parameters:

stringFilterName - the string filter name.

setStreamFilterName

protected void setStreamFilterName(COSName streamFilterName)

Set the stream filter name.

Parameters:

streamFilterName - the stream filter name.

prepareForDecryption

public abstract void prepareForDecryption(PDEncryption encryption,
                                          COSArray documentIDArray,
                                          DecryptionMaterial decryptionMaterial)
                                   throws IOException

Prepares everything to decrypt the document.

Parameters:

encryption - encryption dictionary, can be retrieved via PDDocument.getEncryption()

documentIDArray - document id which is returned via COSDocument.getDocumentID()

decryptionMaterial - Information used to decrypt the document.

Throws:

IOException - If there is an error accessing data.

decryptDataRC4

protected void decryptDataRC4(byte[] finalKey,
                              InputStream input,
                              OutputStream output)
                       throws IOException

Encrypt or decrypt data with RC4.

Parameters:

finalKey - The final key obtained with via calcFinalKey(long, long).

input - The data to encrypt.

output - The output to write the encrypted data to.

Throws:

IOException - If there is an error reading the data.

decryptDataRC4

protected void decryptDataRC4(byte[] finalKey,
                              byte[] input,
                              OutputStream output)
                       throws IOException

Encrypt or decrypt data with RC4.

Parameters:

finalKey - The final key obtained with via calcFinalKey(long, long).

input - The data to encrypt.

output - The output to write the encrypted data to.

Throws:

IOException - If there is an error reading the data.

decrypt

public void decrypt(COSBase obj,
                    long objNum,
                    long genNum)
             throws IOException

This will dispatch to the correct method.

Parameters:

obj - The object to decrypt.

objNum - The object number.

genNum - The object generation Number.

Throws:

IOException - If there is an error getting the stream data.

decryptStream

public void decryptStream(COSStream stream,
                          long objNum,
                          long genNum)
                   throws IOException

This will decrypt a stream.

Parameters:

stream - The stream to decrypt.

objNum - The object number.

genNum - The object generation number.

Throws:

IOException - If there is an error getting the stream data.

getKeyLength

public int getKeyLength()

Getter of the property keyLength.

Returns:

Returns the keyLength.

setKeyLength

public void setKeyLength(int keyLen)

Setter of the property keyLength.

Parameters:

keyLen - The keyLength to set.

setCurrentAccessPermission

public void setCurrentAccessPermission(AccessPermission currentAccessPermission)

Sets the access permissions.

Parameters:

currentAccessPermission - The access permissions to be set.

getCurrentAccessPermission

public AccessPermission getCurrentAccessPermission()

Returns the access permissions that were computed during document decryption. The returned object is in read only mode.

Returns:

the access permissions or null if the document was not decrypted.

isAES

public boolean isAES()

True if AES is used for encryption and decryption.

Returns:

true if AEs is used

setAES

public void setAES(boolean aesValue)

Set to true if AES for encryption and decryption should be used.

Parameters:

aesValue - if true AES will be used

getEncryptionKey

public byte[] getEncryptionKey()

setEncryptionKey

protected void setEncryptionKey(byte[] encryptionKey)

hasProtectionPolicy

public abstract boolean hasProtectionPolicy()

Returns whether a protection policy has been set.

Returns:

true if a protection policy has been set.