Interface PDFDecrypter

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      java.nio.ByteBuffer decryptBuffer​(java.lang.String cryptFilterName, PDFObject streamObj, java.nio.ByteBuffer streamBuf)
      Decrypt a buffer of data
      java.lang.String decryptString​(int objNum, int objGen, java.lang.String inputBasicString)
      Decrypt a basic string.
      boolean isEncryptionPresent()
      Determine whether this actually applies a decryption other than identity decryption.
      boolean isOwnerAuthorised()
      Determine whether the password known by the decrypter indicates that the user is the owner of the document.
    • Method Detail

      • decryptBuffer

        java.nio.ByteBuffer decryptBuffer​(java.lang.String cryptFilterName,
                                          PDFObject streamObj,
                                          java.nio.ByteBuffer streamBuf)
                                   throws PDFParseException
        Decrypt a buffer of data
        Parameters:
        cryptFilterName - the name of the crypt filter, if V4 encryption is being used, where individual crypt filters may be specified for individual streams. If encryption is not using V4 encryption (indicated by V=4 in the Encrypt dictionary) then this must be null. Null may also be specified with V4 encryption to indicate that the default filter should be used.
        streamObj - the object whose stream is being decrypted. The containing object's number and generation contribute to the key used for stream encrypted with the document's default encryption, so this is typically required. Should be null only if a cryptFilterName is specified, as objects with specific stream filters use the general document key, rather than a stream-specific key.
        streamBuf - the buffer to decrypt
        Returns:
        a buffer containing the decrypted stream, positioned at its beginning; will only be the same buffer as streamBuf if the identity decrypter is being used
        Throws:
        PDFParseException - if the named crypt filter does not exist, or if a crypt filter is named when named crypt filters are not supported. Problems due to incorrect passwords are revealed prior to this point.
      • decryptString

        java.lang.String decryptString​(int objNum,
                                       int objGen,
                                       java.lang.String inputBasicString)
                                throws PDFParseException
        Decrypt a basic string.
        Parameters:
        objNum - the object number of the containing object
        objGen - the generation number of the containing object
        inputBasicString - the string to be decrypted
        Returns:
        the decrypted string
        Throws:
        PDFParseException - if the named crypt filter does not exist, or if a crypt filter is named when named crypt filters are not supported. Problems due to incorrect passwords are revealed prior to this point.
      • isOwnerAuthorised

        boolean isOwnerAuthorised()
        Determine whether the password known by the decrypter indicates that the user is the owner of the document. Can be used, in conjunction with isEncryptionPresent() to determine whether any permissions apply.
        Returns:
        whether owner authentication is being used to decrypt the document
      • isEncryptionPresent

        boolean isEncryptionPresent()
        Determine whether this actually applies a decryption other than identity decryption.
        Returns:
        whether encryption is present