Class PDEncryption

  • Direct Known Subclasses:
    PDEncryptionDictionary

    public class PDEncryption
    extends java.lang.Object
    This class is a specialized view of the encryption dictionary of a PDF document. It contains a low level dictionary (COSDictionary) and provides the methods to manage its fields. The available fields are the ones who are involved by standard security handler and public key security handler.
    Author:
    Ben Litchfield, Benoit Guillon
    • Field Detail

      • VERSION0_UNDOCUMENTED_UNSUPPORTED

        public static final int VERSION0_UNDOCUMENTED_UNSUPPORTED
        See PDF Reference 1.4 Table 3.13.
        See Also:
        Constant Field Values
      • VERSION1_40_BIT_ALGORITHM

        public static final int VERSION1_40_BIT_ALGORITHM
        See PDF Reference 1.4 Table 3.13.
        See Also:
        Constant Field Values
      • VERSION2_VARIABLE_LENGTH_ALGORITHM

        public static final int VERSION2_VARIABLE_LENGTH_ALGORITHM
        See PDF Reference 1.4 Table 3.13.
        See Also:
        Constant Field Values
      • VERSION3_UNPUBLISHED_ALGORITHM

        public static final int VERSION3_UNPUBLISHED_ALGORITHM
        See PDF Reference 1.4 Table 3.13.
        See Also:
        Constant Field Values
      • VERSION4_SECURITY_HANDLER

        public static final int VERSION4_SECURITY_HANDLER
        See PDF Reference 1.4 Table 3.13.
        See Also:
        Constant Field Values
      • DEFAULT_NAME

        public static final java.lang.String DEFAULT_NAME
        The default security handler.
        See Also:
        Constant Field Values
      • DEFAULT_LENGTH

        public static final int DEFAULT_LENGTH
        The default length for the encryption key.
        See Also:
        Constant Field Values
      • DEFAULT_VERSION

        public static final int DEFAULT_VERSION
        The default version, according to the PDF Reference.
        See Also:
        Constant Field Values
    • Constructor Detail

      • PDEncryption

        public PDEncryption()
        creates a new empty encryption dictionary.
      • PDEncryption

        public PDEncryption​(COSDictionary dictionary)
        creates a new encryption dictionary from the low level dictionary provided.
        Parameters:
        dictionary - a COS encryption dictionary
    • Method Detail

      • getSecurityHandler

        public SecurityHandler getSecurityHandler()
                                           throws java.io.IOException
        Returns the security handler specified in the dictionary's Filter entry.
        Returns:
        a security handler instance
        Throws:
        java.io.IOException - if there is no security handler available which matches the Filter
      • setSecurityHandler

        public void setSecurityHandler​(SecurityHandler securityHandler)
        Sets the security handler used in this encryption dictionary
        Parameters:
        securityHandler - new security handler
      • hasSecurityHandler

        public boolean hasSecurityHandler()
        Returns true if the security handler specified in the dictionary's Filter is available.
        Returns:
        true if the security handler is available
      • getCOSDictionary

        public COSDictionary getCOSDictionary()
        This will get the dictionary associated with this encryption dictionary.
        Returns:
        The COS dictionary that this object wraps.
      • setFilter

        public void setFilter​(java.lang.String filter)
        Sets the filter entry of the encryption dictionary.
        Parameters:
        filter - The filter name.
      • getFilter

        public final java.lang.String getFilter()
        Get the name of the filter.
        Returns:
        The filter name contained in this encryption dictionary.
      • getSubFilter

        public java.lang.String getSubFilter()
        Get the name of the subfilter.
        Returns:
        The subfilter name contained in this encryption dictionary.
      • setSubFilter

        public void setSubFilter​(java.lang.String subfilter)
        Set the subfilter entry of the encryption dictionary.
        Parameters:
        subfilter - The value of the subfilter field.
      • setVersion

        public void setVersion​(int version)
        This will set the V entry of the encryption dictionary.

        See PDF Reference 1.4 Table 3.13.

        Note: This value is used to decrypt the pdf document. If you change this when the document is encrypted then decryption will fail!.
        Parameters:
        version - The new encryption version.
      • getVersion

        public int getVersion()
        This will return the V entry of the encryption dictionary.

        See PDF Reference 1.4 Table 3.13.
        Returns:
        The encryption version to use.
      • setLength

        public void setLength​(int length)
        This will set the number of bits to use for the encryption algorithm.
        Parameters:
        length - The new key length.
      • getLength

        public int getLength()
        This will return the Length entry of the encryption dictionary.

        The length in bits for the encryption algorithm. This will return a multiple of 8.
        Returns:
        The length in bits for the encryption algorithm
      • setRevision

        public void setRevision​(int revision)
        This will set the R entry of the encryption dictionary.

        See PDF Reference 1.4 Table 3.14.

        Note: This value is used to decrypt the pdf document. If you change this when the document is encrypted then decryption will fail!.
        Parameters:
        revision - The new encryption version.
      • getRevision

        public int getRevision()
        This will return the R entry of the encryption dictionary.

        See PDF Reference 1.4 Table 3.14.
        Returns:
        The encryption revision to use.
      • setOwnerKey

        public void setOwnerKey​(byte[] o)
                         throws java.io.IOException
        This will set the O entry in the standard encryption dictionary.
        Parameters:
        o - A 32 byte array or null if there is no owner key.
        Throws:
        java.io.IOException - If there is an error setting the data.
      • getOwnerKey

        public byte[] getOwnerKey()
                           throws java.io.IOException
        This will get the O entry in the standard encryption dictionary.
        Returns:
        A 32 byte array or null if there is no owner key.
        Throws:
        java.io.IOException - If there is an error accessing the data.
      • setUserKey

        public void setUserKey​(byte[] u)
                        throws java.io.IOException
        This will set the U entry in the standard encryption dictionary.
        Parameters:
        u - A 32 byte array.
        Throws:
        java.io.IOException - If there is an error setting the data.
      • getUserKey

        public byte[] getUserKey()
                          throws java.io.IOException
        This will get the U entry in the standard encryption dictionary.
        Returns:
        A 32 byte array or null if there is no user key.
        Throws:
        java.io.IOException - If there is an error accessing the data.
      • setOwnerEncryptionKey

        public void setOwnerEncryptionKey​(byte[] oe)
                                   throws java.io.IOException
        This will set the OE entry in the standard encryption dictionary.
        Parameters:
        oe - A 32 byte array or null if there is no owner encryption key.
        Throws:
        java.io.IOException - If there is an error setting the data.
      • getOwnerEncryptionKey

        public byte[] getOwnerEncryptionKey()
                                     throws java.io.IOException
        This will get the OE entry in the standard encryption dictionary.
        Returns:
        A 32 byte array or null if there is no owner encryption key.
        Throws:
        java.io.IOException - If there is an error accessing the data.
      • setUserEncryptionKey

        public void setUserEncryptionKey​(byte[] ue)
                                  throws java.io.IOException
        This will set the UE entry in the standard encryption dictionary.
        Parameters:
        ue - A 32 byte array or null if there is no user encryption key.
        Throws:
        java.io.IOException - If there is an error setting the data.
      • getUserEncryptionKey

        public byte[] getUserEncryptionKey()
                                    throws java.io.IOException
        This will get the UE entry in the standard encryption dictionary.
        Returns:
        A 32 byte array or null if there is no user encryption key.
        Throws:
        java.io.IOException - If there is an error accessing the data.
      • setPermissions

        public void setPermissions​(int permissions)
        This will set the permissions bit mask.
        Parameters:
        permissions - The new permissions bit mask
      • getPermissions

        public int getPermissions()
        This will get the permissions bit mask.
        Returns:
        The permissions bit mask.
      • isEncryptMetaData

        public boolean isEncryptMetaData()
        Will get the EncryptMetaData dictionary info.
        Returns:
        true if EncryptMetaData is explicitly set to false (the default is true)
      • setRecipients

        public void setRecipients​(byte[][] recipients)
                           throws java.io.IOException
        This will set the Recipients field of the dictionary. This field contains an array of string.
        Parameters:
        recipients - the array of bytes arrays to put in the Recipients field.
        Throws:
        java.io.IOException - If there is an error setting the data.
      • getRecipientsLength

        public int getRecipientsLength()
        Returns the number of recipients contained in the Recipients field of the dictionary.
        Returns:
        the number of recipients contained in the Recipients field.
      • getRecipientStringAt

        public COSString getRecipientStringAt​(int i)
        returns the COSString contained in the Recipients field at position i.
        Parameters:
        i - the position in the Recipients field array.
        Returns:
        a COSString object containing information about the recipient number i.
      • getStdCryptFilterDictionary

        public PDCryptFilterDictionary getStdCryptFilterDictionary()
        Returns the standard crypt filter.
        Returns:
        the standard crypt filter if available.
      • getCryptFilterDictionary

        public PDCryptFilterDictionary getCryptFilterDictionary​(COSName cryptFilterName)
        Returns the crypt filter with the given name.
        Parameters:
        cryptFilterName - the name of the crypt filter
        Returns:
        the crypt filter with the given name if available
      • setCryptFilterDictionary

        public void setCryptFilterDictionary​(COSName cryptFilterName,
                                             PDCryptFilterDictionary cryptFilterDictionary)
        Sets the crypt filter with the given name.
        Parameters:
        cryptFilterName - the name of the crypt filter
        cryptFilterDictionary - the crypt filter to set
      • setStdCryptFilterDictionary

        public void setStdCryptFilterDictionary​(PDCryptFilterDictionary cryptFilterDictionary)
        Sets the standard crypt filter.
        Parameters:
        cryptFilterDictionary - the standard crypt filter to set
      • getStreamFilterName

        public COSName getStreamFilterName()
        Returns the name of the filter which is used for de/encrypting streams. Default value is "Identity".
        Returns:
        the name of the filter
      • setStreamFilterName

        public void setStreamFilterName​(COSName streamFilterName)
        Sets the name of the filter which is used for de/encrypting streams.
        Parameters:
        streamFilterName - the name of the filter
      • getStringFilterName

        public COSName getStringFilterName()
        Returns the name of the filter which is used for de/encrypting strings. Default value is "Identity".
        Returns:
        the name of the filter
      • setStringFilterName

        public void setStringFilterName​(COSName stringFilterName)
        Sets the name of the filter which is used for de/encrypting strings.
        Parameters:
        stringFilterName - the name of the filter
      • setPerms

        public void setPerms​(byte[] perms)
                      throws java.io.IOException
        Set the Perms entry in the encryption dictionary.
        Parameters:
        perms - A 16 byte array.
        Throws:
        java.io.IOException - If there is an error setting the data.
      • getPerms

        public byte[] getPerms()
                        throws java.io.IOException
        Get the Perms entry in the encryption dictionary.
        Returns:
        A 16 byte array or null if there is no Perms entry.
        Throws:
        java.io.IOException - If there is an error accessing the data.
      • removeV45filters

        public void removeV45filters()
        remove CF, StmF, and StrF entries. This is to be called if V is not 4 or 5.