Added support for 128bit encryption in PDF output. Based on work by Michael Rubin.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1154998 13f79535-47bb-0310-9956-ffa450edef68

7 files changed, 699 insertions, 336 deletions

diff --git a/src/java/org/apache/fop/pdf/FileIDGenerator.java b/src/java/org/apache/fop/pdf/FileIDGenerator.java
new file mode 100644
index 000000000..00aad4426
--- /dev/null
+++ b/src/java/org/apache/fop/pdf/FileIDGenerator.java
@@ -0,0 +1,124 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.pdf;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Random;
+
+/**
+ * A class to generate the File Identifier of a PDF document (the ID entry of the file
+ * trailer dictionary).
+ */
+abstract class FileIDGenerator {
+
+    abstract byte[] getOriginalFileID();
+
+    abstract byte[] getUpdatedFileID();
+
+    private static final class RandomFileIDGenerator extends FileIDGenerator {
+
+        private byte[] fileID;
+
+        private RandomFileIDGenerator() {
+            Random random = new Random();
+            fileID = new byte[16];
+            random.nextBytes(fileID);
+        }
+
+        @Override
+        byte[] getOriginalFileID() {
+            return fileID;
+        }
+
+        @Override
+        byte[] getUpdatedFileID() {
+            return fileID;
+        }
+
+    }
+
+    private static final class DigestFileIDGenerator extends FileIDGenerator {
+
+        private byte[] fileID;
+
+        private final PDFDocument document;
+
+        private final MessageDigest digest;
+
+        DigestFileIDGenerator(PDFDocument document) throws NoSuchAlgorithmException {
+            this.document = document;
+            this.digest = MessageDigest.getInstance("MD5");
+        }
+
+        @Override
+        byte[] getOriginalFileID() {
+            if (fileID == null) {
+                generateFileID();
+            }
+            return fileID;
+        }
+
+        @Override
+        byte[] getUpdatedFileID() {
+            return getOriginalFileID();
+        }
+
+        private void generateFileID() {
+            DateFormat df = new SimpleDateFormat("yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'SSS");
+            digest.update(PDFDocument.encode(df.format(new Date())));
+            // Ignoring the filename here for simplicity even though it's recommended
+            // by the PDF spec
+            digest.update(PDFDocument.encode(String.valueOf(document.getCurrentFileSize())));
+            digest.update(document.getInfo().toPDF());
+            fileID = digest.digest();
+        }
+
+    }
+
+    /**
+     * Use this method when the file ID is needed before the document is finalized. The
+     * digest method recommended by the PDF Reference is based, among other things, on the
+     * file size.
+     *
+     * @return an instance that generates a random sequence of bytes for the File
+     * Identifier
+     */
+    static FileIDGenerator getRandomFileIDGenerator() {
+        return new RandomFileIDGenerator();
+    }
+
+    /**
+     * Returns an instance that generates a file ID using the digest method recommended by
+     * the PDF Reference. To properly follow the Reference, the size of the document must
+     * no longer change after this method is called.
+     *
+     * @param document the document whose File Identifier must be generated
+     * @return the generator
+     * @throws NoSuchAlgorithmException if the MD5 Digest algorithm is not available
+     */
+    static FileIDGenerator getDigestFileIDGenerator(PDFDocument document)
+            throws NoSuchAlgorithmException {
+        return new DigestFileIDGenerator(document);
+    }
+}
diff --git a/src/java/org/apache/fop/pdf/PDFDocument.java b/src/java/org/apache/fop/pdf/PDFDocument.java
index 9268ae921..cbca3ea8f 100644
--- a/src/java/org/apache/fop/pdf/PDFDocument.java
+++ b/src/java/org/apache/fop/pdf/PDFDocument.java
@@ -25,10 +25,7 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.UnsupportedEncodingException;
 import java.io.Writer;
-import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
-import java.text.DateFormat;
-import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
@@ -186,6 +183,8 @@ public class PDFDocument {
 
     private boolean encodingOnTheFly = true;
 
+    private FileIDGenerator fileIDGenerator;
+
     /**
      * Creates an empty PDF document.
      *
@@ -513,10 +512,10 @@ public class PDFDocument {
      */
     public void setEncryption(PDFEncryptionParams params) {
         getProfile().verifyEncryptionAllowed();
-        this.encryption = PDFEncryptionManager.newInstance(++this.objectcount, params);
+        fileIDGenerator = FileIDGenerator.getRandomFileIDGenerator();
+        this.encryption = PDFEncryptionManager.newInstance(++this.objectcount, params, this);
         if (this.encryption != null) {
             PDFObject pdfObject = (PDFObject)this.encryption;
-            pdfObject.setDocument(this);
             addTrailerObject(pdfObject);
         } else {
             log.warn(
@@ -979,27 +978,6 @@ public class PDFDocument {
         this.position += bin.length;
     }
 
-    /** @return the "ID" entry for the file trailer */
-    protected String getIDEntry() {
-        try {
-            MessageDigest digest = MessageDigest.getInstance("MD5");
-            DateFormat df = new SimpleDateFormat("yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'SSS");
-            digest.update(encode(df.format(new Date())));
-            //Ignoring the filename here for simplicity even though it's recommended by the PDF spec
-            digest.update(encode(String.valueOf(this.position)));
-            digest.update(getInfo().toPDF());
-            byte[] res = digest.digest();
-            String s = PDFText.toHex(res);
-            return "/ID [" + s + " " + s + "]";
-        } catch (NoSuchAlgorithmException e) {
-            if (getProfile().isIDEntryRequired()) {
-                throw new UnsupportedOperationException("MD5 not available: " + e.getMessage());
-            } else {
-                return ""; //Entry is optional if PDF/A or PDF/X are not active
-            }
-        }
-    }
-
     /**
      * Write the trailer
      *
@@ -1038,7 +1016,9 @@ public class PDFDocument {
         if (this.isEncryptionActive()) {
             pdf.append(this.encryption.getTrailerEntry());
         } else {
-            pdf.append(this.getIDEntry());
+            byte[] fileID = getFileIDGenerator().getOriginalFileID();
+            String fileIDAsString = PDFText.toHex(fileID);
+            pdf.append("/ID [" + fileIDAsString + " " + fileIDAsString + "]");
         }
 
         pdf.append("\n>>\nstartxref\n")
@@ -1089,4 +1069,18 @@ public class PDFDocument {
         return pdfBytes.length;
     }
 
+    long getCurrentFileSize() {
+        return position;
+    }
+
+    FileIDGenerator getFileIDGenerator() {
+        if (fileIDGenerator == null) {
+            try {
+                fileIDGenerator = FileIDGenerator.getDigestFileIDGenerator(this);
+            } catch (NoSuchAlgorithmException e) {
+                fileIDGenerator = FileIDGenerator.getRandomFileIDGenerator();
+            }
+        }
+        return fileIDGenerator;
+    }
 }
diff --git a/src/java/org/apache/fop/pdf/PDFEncryption.java b/src/java/org/apache/fop/pdf/PDFEncryption.java
index 5852df157..277cf0a94 100644
--- a/src/java/org/apache/fop/pdf/PDFEncryption.java
+++ b/src/java/org/apache/fop/pdf/PDFEncryption.java
@@ -25,18 +25,6 @@ package org.apache.fop.pdf;
 public interface PDFEncryption {
 
     /**
-     * Returns the encryption parameters.
-     * @return the encryption parameters
-     */
-    PDFEncryptionParams getParams();
-
-    /**
-     * Sets the encryption parameters.
-     * @param params The parameterss to set
-     */
-    void setParams(PDFEncryptionParams params);
-
-    /**
      * Adds a PDFFilter to the PDFStream object
      * @param stream the stream to add an encryption filter to
      */
diff --git a/src/java/org/apache/fop/pdf/PDFEncryptionJCE.java b/src/java/org/apache/fop/pdf/PDFEncryptionJCE.java
index 269f0639d..c9b9c58ba 100644
--- a/src/java/org/apache/fop/pdf/PDFEncryptionJCE.java
+++ b/src/java/org/apache/fop/pdf/PDFEncryptionJCE.java
@@ -19,13 +19,12 @@
 
 package org.apache.fop.pdf;
 
-// Java
 import java.io.IOException;
 import java.io.OutputStream;
 import java.security.InvalidKeyException;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
-import java.util.Random;
+import java.util.Arrays;
 
 import javax.crypto.BadPaddingException;
 import javax.crypto.Cipher;
@@ -35,310 +34,427 @@ import javax.crypto.NoSuchPaddingException;
 import javax.crypto.spec.SecretKeySpec;
 
 /**
- * class representing a /Filter /Standard object.
- *
+ * An implementation of the Standard Security Handler.
  */
-public class PDFEncryptionJCE extends PDFObject implements PDFEncryption {
+public final class PDFEncryptionJCE extends PDFObject implements PDFEncryption {
 
-    private class EncryptionFilter extends PDFFilter {
-        private PDFEncryptionJCE encryption;
-        private int number;
-        private int generation;
+    private final MessageDigest digest;
 
-        /**
-         * The constructor for the internal PDFEncryptionJCE filter
-         * @param encryption The encryption object to use
-         * @param number The number of the object to be encrypted
-         * @param generation The generation of the object to be encrypted
-         */
-        public EncryptionFilter(PDFEncryptionJCE encryption,
-                                int number, int generation) {
-            super();
-            this.encryption = encryption;
-            this.number  = number;
-            this.generation = generation;
-            log.debug("new encryption filter for number "
-                + number + " and generation " + generation);
+    private byte[] encryptionKey;
+
+    private String encryptionDictionary;
+
+    private class EncryptionInitializer {
+
+        private final PDFEncryptionParams encryptionParams;
+
+        private int encryptionLength;
+
+        private int version;
+
+        private int revision;
+
+        EncryptionInitializer(PDFEncryptionParams params) {
+            this.encryptionParams = new PDFEncryptionParams(params);
         }
 
+        void init() {
+            encryptionLength = encryptionParams.getEncryptionLengthInBits();
+            determineEncryptionAlgorithm();
+            int permissions = Permission.computePermissions(encryptionParams);
+            EncryptionSettings encryptionSettings = new EncryptionSettings(
+                    encryptionLength, permissions,
+                    encryptionParams.getUserPassword(), encryptionParams.getOwnerPassword());
+            InitializationEngine initializationEngine = (revision == 2)
+                    ? new Rev2Engine(encryptionSettings)
+                    : new Rev3Engine(encryptionSettings);
+            initializationEngine.run();
+            encryptionDictionary = createEncryptionDictionary(getObjectID(), permissions,
+                    initializationEngine.oValue, initializationEngine.uValue);
+        }
+
+        private void determineEncryptionAlgorithm() {
+            if (isVersion1Revision2Algorithm()) {
+                version = 1;
+                revision = 2;
+            } else {
+                version = 2;
+                revision = 3;
+            }
+        }
+
+        private boolean isVersion1Revision2Algorithm() {
+            return encryptionLength == 40
+                    && encryptionParams.isAllowFillInForms()
+                    && encryptionParams.isAllowAccessContent()
+                    && encryptionParams.isAllowAssembleDocument()
+                    && encryptionParams.isAllowPrintHq();
+        }
+
+        private String createEncryptionDictionary(final String objectId, final int permissions,
+                final byte[] oValue, final byte[] uValue) {
+            return objectId
+                    + "<< /Filter /Standard\n"
+                    + "/V " + version + "\n"
+                    + "/R " + revision + "\n"
+                    + "/Length " + encryptionLength + "\n"
+                    + "/P "  + permissions + "\n"
+                    + "/O " + PDFText.toHex(oValue) + "\n"
+                    + "/U " + PDFText.toHex(uValue) + "\n"
+                    + ">>\n"
+                    + "endobj\n";
+        }
+
+    }
+
+    private static enum Permission {
+
+        PRINT(3),
+        EDIT_CONTENT(4),
+        COPY_CONTENT(5),
+        EDIT_ANNOTATIONS(6),
+        FILL_IN_FORMS(9),
+        ACCESS_CONTENT(10),
+        ASSEMBLE_DOCUMENT(11),
+        PRINT_HQ(12);
+
+        private final int mask;
+
         /**
-         * Return a PDF string representation of the filter. In this
-         * case no filter name is passed.
-         * @return The filter name, blank in this case
+         * Creates a new permission.
+         *
+         * @param bit bit position for this permission, 1-based to match the PDF Reference
          */
-        public String getName() {
-            return "";
+        private Permission(int bit) {
+            mask = 1 << (bit - 1);
+        }
+
+        private int removeFrom(int permissions) {
+            return permissions - mask;
+        }
+
+        static int computePermissions(PDFEncryptionParams encryptionParams) {
+            int permissions = -4;
+
+            if (!encryptionParams.isAllowPrint()) {
+                permissions = PRINT.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowCopyContent()) {
+                permissions = COPY_CONTENT.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowEditContent()) {
+                permissions = EDIT_CONTENT.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowEditAnnotations()) {
+                permissions = EDIT_ANNOTATIONS.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowFillInForms()) {
+                permissions = FILL_IN_FORMS.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowAccessContent()) {
+                permissions = ACCESS_CONTENT.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowAssembleDocument()) {
+                permissions = ASSEMBLE_DOCUMENT.removeFrom(permissions);
+            }
+            if (!encryptionParams.isAllowPrintHq()) {
+                permissions = PRINT_HQ.removeFrom(permissions);
+            }
+            return permissions;
+        }
+    }
+
+    private static final class EncryptionSettings {
+
+        final int encryptionLength; // CSOK: VisibilityModifier
+
+        final int permissions; // CSOK: VisibilityModifier
+
+        final String userPassword; // CSOK: VisibilityModifier
+
+        final String ownerPassword; // CSOK: VisibilityModifier
+
+        EncryptionSettings(int encryptionLength, int permissions,
+                String userPassword, String ownerPassword) {
+            this.encryptionLength = encryptionLength;
+            this.permissions = permissions;
+            this.userPassword = userPassword;
+            this.ownerPassword = ownerPassword;
+        }
+
+    }
+
+    private abstract class InitializationEngine {
+
+        /** Padding for passwords. */
+        protected final byte[] padding = new byte[] {
+                (byte) 0x28, (byte) 0xBF, (byte) 0x4E, (byte) 0x5E,
+                (byte) 0x4E, (byte) 0x75, (byte) 0x8A, (byte) 0x41,
+                (byte) 0x64, (byte) 0x00, (byte) 0x4E, (byte) 0x56,
+                (byte) 0xFF, (byte) 0xFA, (byte) 0x01, (byte) 0x08,
+                (byte) 0x2E, (byte) 0x2E, (byte) 0x00, (byte) 0xB6,
+                (byte) 0xD0, (byte) 0x68, (byte) 0x3E, (byte) 0x80,
+                (byte) 0x2F, (byte) 0x0C, (byte) 0xA9, (byte) 0xFE,
+                (byte) 0x64, (byte) 0x53, (byte) 0x69, (byte) 0x7A};
+
+        protected final int encryptionLengthInBytes;
+
+        private final int permissions;
+
+        private byte[] oValue;
+
+        private byte[] uValue;
+
+        private final byte[] preparedUserPassword;
+
+        protected final String ownerPassword;
+
+        InitializationEngine(EncryptionSettings encryptionSettings) {
+            this.encryptionLengthInBytes = encryptionSettings.encryptionLength / 8;
+            this.permissions = encryptionSettings.permissions;
+            this.preparedUserPassword = preparePassword(encryptionSettings.userPassword);
+            this.ownerPassword = encryptionSettings.ownerPassword;
+        }
+
+        void run() {
+            oValue = computeOValue();
+            createEncryptionKey();
+            uValue = computeUValue();
         }
 
         /**
-         * Return a parameter dictionary for this filter, or null
-         * @return The parameter dictionary. In this case, null.
+         * Applies Algorithm 3.3 Page 79 of the PDF 1.4 Reference.
+         *
+         * @return the O value
          */
-        public PDFObject getDecodeParms() {
-            return null;
+        private byte[] computeOValue() {
+            // Step 1
+            byte[] md5Input = prepareMD5Input();
+            // Step 2
+            digest.reset();
+            byte[] hash = digest.digest(md5Input);
+            // Step 3
+            hash = computeOValueStep3(hash);
+            // Step 4
+            byte[] key = new byte[encryptionLengthInBytes];
+            System.arraycopy(hash, 0, key, 0, encryptionLengthInBytes);
+            // Steps 5, 6
+            byte[] encryptionResult = encryptWithKey(key, preparedUserPassword);
+            // Step 7
+            encryptionResult = computeOValueStep7(key, encryptionResult);
+            // Step 8
+            return encryptionResult;
         }
 
         /**
-         * {@inheritDoc}
+         * Applies Algorithm 3.2 Page 78 of the PDF 1.4 Reference.
          */
-        public OutputStream applyFilter(OutputStream out) throws IOException {
-            return new CipherOutputStream(out,
-                    encryption.initCipher(number, generation));
+        private void createEncryptionKey() {
+            // Steps 1, 2
+            digest.reset();
+            digest.update(preparedUserPassword);
+            // Step 3
+            digest.update(oValue);
+            // Step 4
+            digest.update((byte) (permissions >>> 0));
+            digest.update((byte) (permissions >>> 8));
+            digest.update((byte) (permissions >>> 16));
+            digest.update((byte) (permissions >>> 24));
+            // Step 5
+            digest.update(getDocumentSafely().getFileIDGenerator().getOriginalFileID());
+            byte[] hash = digest.digest();
+            // Step 6
+            hash = createEncryptionKeyStep6(hash);
+            // Step 7
+            encryptionKey = new byte[encryptionLengthInBytes];
+            System.arraycopy(hash, 0, encryptionKey, 0, encryptionLengthInBytes);
         }
 
-    }
+        protected abstract byte[] computeUValue();
 
-    private static final char [] PAD
-                             = {0x28, 0xBF, 0x4E, 0x5E, 0x4E, 0x75, 0x8A, 0x41,
-                                0x64, 0x00, 0x4E, 0x56, 0xFF, 0xFA, 0x01, 0x08,
-                                0x2E, 0x2E, 0x00, 0xB6, 0xD0, 0x68, 0x3E, 0x80,
-                                0x2F, 0x0C, 0xA9, 0xFE, 0x64, 0x53, 0x69, 0x7A};
-
-    /** Value of PRINT permission */
-    public static final int PERMISSION_PRINT            =  4;
-    /** Value of content editting permission */
-    public static final int PERMISSION_EDIT_CONTENT     =  8;
-    /** Value of content extraction permission */
-    public static final int PERMISSION_COPY_CONTENT     = 16;
-    /** Value of annotation editting permission */
-    public static final int PERMISSION_EDIT_ANNOTATIONS = 32;
-
-    // Encryption tools
-    private MessageDigest digest = null;
-    //private Cipher cipher = null;
-    private Random random = new Random();
-    // Control attributes
-    private PDFEncryptionParams params;
-    // Output attributes
-    private byte[] fileID = null;
-    private byte[] encryptionKey = null;
-    private String dictionary = null;
+        /**
+         * Adds padding to the password as directed in page 78 of the PDF 1.4 Reference.
+         *
+         * @param password the password
+         * @return the password with additional padding if necessary
+         */
+        private byte[] preparePassword(String password) {
+            int finalLength = 32;
+            byte[] preparedPassword = new byte[finalLength];
+            byte[] passwordBytes = password.getBytes();
+            System.arraycopy(passwordBytes, 0, preparedPassword, 0, passwordBytes.length);
+            System.arraycopy(padding, 0, preparedPassword, passwordBytes.length,
+                    finalLength - passwordBytes.length);
+            return preparedPassword;
+        }
 
-    /**
-     * Create a /Filter /Standard object.
-     *
-     * @param objnum the object's number
-     */
-    public PDFEncryptionJCE(int objnum) {
-        /* generic creation of object */
-        super();
-        setObjectNumber(objnum);
-        try {
-            digest = MessageDigest.getInstance("MD5");
-            //cipher = Cipher.getInstance("RC4");
-        } catch (NoSuchAlgorithmException e) {
-            throw new UnsupportedOperationException(e.getMessage());
-        /*} catch (NoSuchPaddingException e) {
-            throw new UnsupportedOperationException(e.getMessage());*/
+        private byte[] prepareMD5Input() {
+            if (ownerPassword.length() != 0) {
+                return preparePassword(ownerPassword);
+            } else {
+                return preparedUserPassword;
+            }
         }
-    }
 
-    /**
-     * Local factory method.
-     * @param objnum PDF object number for the encryption object
-     * @param params PDF encryption parameters
-     * @return PDFEncryption the newly created PDFEncryption object
-     */
-    public static PDFEncryption make(int objnum, PDFEncryptionParams params) {
-        PDFEncryptionJCE impl = new PDFEncryptionJCE(objnum);
-        impl.setParams(params);
-        impl.init();
-        return impl;
-    }
+        protected abstract byte[] computeOValueStep3(byte[] hash);
 
+        protected abstract byte[] computeOValueStep7(byte[] key, byte[] encryptionResult);
 
-    /**
-     * Returns the encryption parameters.
-     * @return the encryption parameters
-     */
-    public PDFEncryptionParams getParams() {
-        return this.params;
-    }
+        protected abstract byte[] createEncryptionKeyStep6(byte[] hash);
 
-    /**
-     * Sets the encryption parameters.
-     * @param params The parameterss to set
-     */
-    public void setParams(PDFEncryptionParams params) {
-        this.params = params;
     }
 
-    // Internal procedures
+    private class Rev2Engine extends InitializationEngine {
 
-    private byte[] prepPassword(String password) {
-        byte[] obuffer = new byte[32];
-        byte[] pbuffer = password.getBytes();
+        Rev2Engine(EncryptionSettings encryptionSettings) {
+            super(encryptionSettings);
+        }
 
-        int i = 0;
-        int j = 0;
+        @Override
+        protected byte[] computeOValueStep3(byte[] hash) {
+            return hash;
+        }
 
-        while (i < obuffer.length && i < pbuffer.length) {
-            obuffer[i] = pbuffer[i];
-            i++;
+        @Override
+        protected byte[] computeOValueStep7(byte[] key, byte[] encryptionResult) {
+            return encryptionResult;
         }
-        while (i < obuffer.length) {
-            obuffer[i++] = (byte) PAD[j++];
+
+        @Override
+        protected byte[] createEncryptionKeyStep6(byte[] hash) {
+            return hash;
+        }
+
+        @Override
+        protected byte[] computeUValue() {
+            return encryptWithKey(encryptionKey, padding);
         }
 
-        return obuffer;
     }
 
-    /**
-     * Returns the document file ID
-     * @return The file ID
-     */
-    public byte[] getFileID() {
-        if (fileID == null) {
-            fileID = new byte[16];
-            random.nextBytes(fileID);
+    private class Rev3Engine extends InitializationEngine {
+
+        Rev3Engine(EncryptionSettings encryptionSettings) {
+            super(encryptionSettings);
         }
 
-        return fileID;
-    }
+        @Override
+        protected byte[] computeOValueStep3(byte[] hash) {
+            for (int i = 0; i < 50; i++) {
+                hash = digest.digest(hash);
+            }
+            return hash;
+        }
 
-    /**
-     * This method returns the indexed file ID
-     * @param index The index to access the file ID
-     * @return The file ID
-     */
-    public String getFileID(int index) {
-        if (index == 1) {
-            return PDFText.toHex(getFileID());
+        @Override
+        protected byte[] computeOValueStep7(byte[] key, byte[] encryptionResult) {
+            return xorKeyAndEncrypt19Times(key, encryptionResult);
         }
 
-        byte[] id = new byte[16];
-        random.nextBytes(id);
-        return PDFText.toHex(id);
-    }
+        @Override
+        protected byte[] createEncryptionKeyStep6(byte[] hash) {
+            for (int i = 0; i < 50; i++) {
+                digest.update(hash, 0, encryptionLengthInBytes);
+                hash = digest.digest();
+            }
+            return hash;
+        }
 
-    private byte[] encryptWithKey(byte[] data, byte[] key) {
-        try {
-            final Cipher c = initCipher(key);
-            return c.doFinal(data);
-        } catch (IllegalBlockSizeException e) {
-            throw new IllegalStateException(e.getMessage());
-        } catch (BadPaddingException e) {
-            throw new IllegalStateException(e.getMessage());
+        @Override
+        protected byte[] computeUValue() {
+            // Step 1 is encryptionKey
+            // Step 2
+            digest.reset();
+            digest.update(padding);
+            // Step 3
+            digest.update(getDocumentSafely().getFileIDGenerator().getOriginalFileID());
+            // Step 4
+            byte[] encryptionResult = encryptWithKey(encryptionKey, digest.digest());
+            // Step 5
+            encryptionResult = xorKeyAndEncrypt19Times(encryptionKey, encryptionResult);
+            // Step 6
+            byte[] uValue = new byte[32];
+            System.arraycopy(encryptionResult, 0, uValue, 0, 16);
+            // Add the arbitrary padding
+            Arrays.fill(uValue, 16, 32, (byte) 0);
+            return uValue;
         }
-    }
 
-    private Cipher initCipher(byte[] key) {
-        try {
-            Cipher c = Cipher.getInstance("RC4");
-            SecretKeySpec keyspec = new SecretKeySpec(key, "RC4");
-            c.init(Cipher.ENCRYPT_MODE, keyspec);
-            return c;
-        } catch (InvalidKeyException e) {
-            throw new IllegalStateException(e.getMessage());
-        } catch (NoSuchAlgorithmException e) {
-            throw new UnsupportedOperationException(e.getMessage());
-        } catch (NoSuchPaddingException e) {
-            throw new UnsupportedOperationException(e.getMessage());
+        private byte[] xorKeyAndEncrypt19Times(byte[] key, byte[] input) {
+            byte[] result = input;
+            byte[] encryptionKey = new byte[key.length];
+            for (int i = 1; i <= 19; i++) {
+                for (int j = 0; j < key.length; j++) {
+                    encryptionKey[j] = (byte) (key[j] ^ i);
+                }
+                result = encryptWithKey(encryptionKey, result);
+            }
+            return result;
         }
-    }
 
-    private Cipher initCipher(int number, int generation) {
-        byte[] hash = calcHash(number, generation);
-        int size = hash.length;
-        hash = digest.digest(hash);
-        byte[] key = calcKey(hash, size);
-        return initCipher(key);
     }
 
-    private byte[] encryptWithHash(byte[] data, byte[] hash, int size) {
-        hash = digest.digest(hash);
+    private class EncryptionFilter extends PDFFilter {
 
-        byte[] key = calcKey(hash, size);
+        private int streamNumber;
 
-        return encryptWithKey(data, key);
-    }
+        private int streamGeneration;
 
-    private byte[] calcKey(byte[] hash, int size) {
-        byte[] key = new byte[size];
+        EncryptionFilter(int streamNumber, int streamGeneration) {
+            this.streamNumber  = streamNumber;
+            this.streamGeneration = streamGeneration;
+        }
 
-        for (int i = 0; i < size; i++) {
-            key[i] = hash[i];
+        /**
+         * Returns a PDF string representation of this filter.
+         *
+         * @return the empty string
+         */
+        public String getName() {
+            return "";
         }
-        return key;
+
+        /**
+         * Returns a parameter dictionary for this filter.
+         *
+         * @return null, this filter has no parameters
+         */
+        public PDFObject getDecodeParms() {
+            return null;
+        }
+
+        /** {@inheritDoc} */
+        public OutputStream applyFilter(OutputStream out) throws IOException {
+            byte[] key = createEncryptionKey(streamNumber, streamGeneration);
+            Cipher cipher = initCipher(key);
+            return new CipherOutputStream(out, cipher);
+        }
+
     }
 
-    /**
-     * This method initializes the encryption algorithms and values
-     */
-    public void init() {
-        // Generate the owner value
-        byte[] oValue;
-        if (params.getOwnerPassword().length() > 0) {
-            oValue = encryptWithHash(
-                    prepPassword(params.getUserPassword()),
-                    prepPassword(params.getOwnerPassword()), 5);
-        } else {
-            oValue = encryptWithHash(
-                    prepPassword(params.getUserPassword()),
-                    prepPassword(params.getUserPassword()), 5);
-        }
-
-        // Generate permissions value
-        int permissions = -4;
-
-        if (!params.isAllowPrint()) {
-            permissions -= PERMISSION_PRINT;
-        }
-        if (!params.isAllowCopyContent()) {
-            permissions -= PERMISSION_COPY_CONTENT;
-        }
-        if (!params.isAllowEditContent()) {
-            permissions -= PERMISSION_EDIT_CONTENT;
-        }
-        if (!params.isAllowEditAnnotations()) {
-            permissions -= PERMISSION_EDIT_ANNOTATIONS;
-        }
-
-        // Create the encrption key
-        digest.update(prepPassword(params.getUserPassword()));
-        digest.update(oValue);
-        digest.update((byte) (permissions >>> 0));
-        digest.update((byte) (permissions >>> 8));
-        digest.update((byte) (permissions >>> 16));
-        digest.update((byte) (permissions >>> 24));
-        digest.update(getFileID());
-
-        byte [] hash = digest.digest();
-        this.encryptionKey = new byte[5];
-
-        for (int i = 0; i < 5; i++) {
-            this.encryptionKey[i] = hash[i];
-        }
-
-        // Create the user value
-        byte[] uValue = encryptWithKey(prepPassword(""), this.encryptionKey);
-
-        // Create the dictionary
-        this.dictionary = getObjectID()
-                        + "<< /Filter /Standard\n"
-                        + "/V 1\n"
-                        + "/R 2\n"
-                        + "/Length 40\n"
-                        + "/P "  + permissions + "\n"
-                        + "/O " + PDFText.toHex(oValue) + "\n"
-                        + "/U " + PDFText.toHex(uValue) + "\n"
-                        + ">>\n"
-                        + "endobj\n";
+    private PDFEncryptionJCE(int objectNumber, PDFEncryptionParams params, PDFDocument pdf) {
+        setObjectNumber(objectNumber);
+        try {
+            digest = MessageDigest.getInstance("MD5");
+        } catch (NoSuchAlgorithmException e) {
+            throw new UnsupportedOperationException(e.getMessage());
+        }
+        setDocument(pdf);
+        EncryptionInitializer encryptionInitializer = new EncryptionInitializer(params);
+        encryptionInitializer.init();
     }
 
     /**
-     * This method encrypts the passed data using the generated keys.
-     * @param data The data to be encrypted
-     * @param number The block number
-     * @param generation The block generation
-     * @return The encrypted data
+     * Creates and returns an encryption object.
+     *
+     * @param objectNumber the object number for the encryption dictionary
+     * @param params the encryption parameters
+     * @param pdf the PDF document to be encrypted
+     * @return the newly created encryption object
      */
-    public byte[] encryptData(byte[] data, int number, int generation) {
-        if (this.encryptionKey == null) {
-            throw new IllegalStateException("PDF Encryption has not been initialized");
-        }
-        byte[] hash = calcHash(number, generation);
-        return encryptWithHash(data, hash, hash.length);
+    public static PDFEncryption make(
+            int objectNumber, PDFEncryptionParams params, PDFDocument pdf) {
+        return new PDFEncryptionJCE(objectNumber, params, pdf);
     }
 
     /** {@inheritDoc} */
@@ -350,63 +466,95 @@ public class PDFEncryptionJCE extends PDFObject implements PDFEncryption {
         if (o == null) {
             throw new IllegalStateException("No object number could be obtained for a PDF object");
         }
-        return encryptData(data, o.getObjectNumber(), o.getGeneration());
+        byte[] key = createEncryptionKey(o.getObjectNumber(), o.getGeneration());
+        return encryptWithKey(key, data);
     }
 
-    private byte[] calcHash(int number, int generation) {
-        byte[] hash = new byte[this.encryptionKey.length + 5];
-
-        int i = 0;
-        while (i < this.encryptionKey.length) {
-            hash[i] = this.encryptionKey[i]; i++;
-        }
-
-        hash[i++] = (byte) (number >>> 0);
-        hash[i++] = (byte) (number >>> 8);
-        hash[i++] = (byte) (number >>> 16);
-        hash[i++] = (byte) (generation >>> 0);
-        hash[i++] = (byte) (generation >>> 8);
-        return hash;
-    }
-
-    /**
-     * Creates PDFFilter for the encryption object
-     * @param number The object number
-     * @param generation The objects generation
-     * @return The resulting filter
-     */
-    public PDFFilter makeFilter(int number, int generation) {
-        return new EncryptionFilter(this, number, generation);
-    }
-
-    /**
-     * Adds a PDFFilter to the PDFStream object
-     * @param stream the stream to add an encryption filter to
-     */
+    /** {@inheritDoc} */
     public void applyFilter(AbstractPDFStream stream) {
         stream.getFilterList().addFilter(
-                this.makeFilter(stream.getObjectNumber(), stream.getGeneration()));
+                new EncryptionFilter(stream.getObjectNumber(), stream.getGeneration()));
     }
 
     /**
-     * Represent the object in PDF
+     *  Prepares the encryption dictionary for output to a PDF file.
      *
-     * @return the PDF
+     *  @return the encryption dictionary as a byte array
      */
     public byte[] toPDF() {
-        if (this.dictionary == null) {
-            throw new IllegalStateException("PDF Encryption has not been initialized");
+        assert encryptionDictionary != null;
+        return encode(this.encryptionDictionary);
+    }
+
+    /** {@inheritDoc} */
+    public String getTrailerEntry() {
+        PDFDocument doc = getDocumentSafely();
+        FileIDGenerator gen = doc.getFileIDGenerator();
+        return "/Encrypt " + getObjectNumber() + " "
+                    + getGeneration() + " R\n"
+                    + "/ID["
+                    + PDFText.toHex(gen.getOriginalFileID())
+                    + PDFText.toHex(gen.getUpdatedFileID())
+                    + "]\n";
+    }
+
+    private static byte[] encryptWithKey(byte[] key, byte[] data) {
+        try {
+            final Cipher c = initCipher(key);
+            return c.doFinal(data);
+        } catch (IllegalBlockSizeException e) {
+            throw new IllegalStateException(e.getMessage());
+        } catch (BadPaddingException e) {
+            throw new IllegalStateException(e.getMessage());
         }
+    }
 
-        return encode(this.dictionary);
+    private static Cipher initCipher(byte[] key) {
+        try {
+            Cipher c = Cipher.getInstance("RC4");
+            SecretKeySpec keyspec = new SecretKeySpec(key, "RC4");
+            c.init(Cipher.ENCRYPT_MODE, keyspec);
+            return c;
+        } catch (InvalidKeyException e) {
+            throw new IllegalStateException(e);
+        } catch (NoSuchAlgorithmException e) {
+            throw new UnsupportedOperationException(e);
+        } catch (NoSuchPaddingException e) {
+            throw new UnsupportedOperationException(e);
+        }
     }
 
     /**
-     * {@inheritDoc}
+     * Applies Algorithm 3.1 from the PDF 1.4 Reference.
+     *
+     * @param objectNumber the object number
+     * @param generationNumber the generation number
+     * @return the key to use for encryption
      */
-    public String getTrailerEntry() {
-        return "/Encrypt " + getObjectNumber() + " "
-                    + getGeneration() + " R\n"
-                    + "/ID[" + getFileID(1) + getFileID(2) + "]\n";
+    private byte[] createEncryptionKey(int objectNumber, int generationNumber) {
+        // Step 1 passed in
+        // Step 2
+        byte[] md5Input = prepareMD5Input(objectNumber, generationNumber);
+        // Step 3
+        digest.reset();
+        byte[] hash = digest.digest(md5Input);
+        // Step 4
+        int keyLength = Math.min(16, md5Input.length);
+        byte[] key = new byte[keyLength];
+        System.arraycopy(hash, 0, key, 0, keyLength);
+        return key;
     }
+
+    private byte[] prepareMD5Input(int objectNumber, int generationNumber) {
+        byte[] md5Input = new byte[encryptionKey.length + 5];
+        System.arraycopy(encryptionKey, 0, md5Input, 0, encryptionKey.length);
+        int i = encryptionKey.length;
+        md5Input[i++] = (byte) (objectNumber >>> 0);
+        md5Input[i++] = (byte) (objectNumber >>> 8);
+        md5Input[i++] = (byte) (objectNumber >>> 16);
+        md5Input[i++] = (byte) (generationNumber >>> 0);
+        md5Input[i++] = (byte) (generationNumber >>> 8);
+        return md5Input;
+    }
+
 }
diff --git a/src/java/org/apache/fop/pdf/PDFEncryptionManager.java b/src/java/org/apache/fop/pdf/PDFEncryptionManager.java
index 3f5ae2a3d..6e57b1518 100644
--- a/src/java/org/apache/fop/pdf/PDFEncryptionManager.java
+++ b/src/java/org/apache/fop/pdf/PDFEncryptionManager.java
@@ -109,16 +109,18 @@ public final class PDFEncryptionManager {
      * Creates a new PDFEncryption instance if PDF encryption is available.
      * @param objnum PDF object number
      * @param params PDF encryption parameters
+     * @param pdf the PDF document to encrypt
      * @return PDFEncryption the newly created instance, null if PDF encryption
      * is unavailable.
      */
-    public static PDFEncryption newInstance(int objnum, PDFEncryptionParams params) {
+    public static PDFEncryption newInstance(int objnum, PDFEncryptionParams params,
+            PDFDocument pdf) {
         try {
-            Class clazz = Class.forName("org.apache.fop.pdf.PDFEncryptionJCE");
+            Class<?> clazz = Class.forName("org.apache.fop.pdf.PDFEncryptionJCE");
             Method makeMethod = clazz.getMethod("make",
-                        new Class[] {int.class, PDFEncryptionParams.class});
+                        new Class[] {int.class, PDFEncryptionParams.class, PDFDocument.class});
             Object obj = makeMethod.invoke(null,
-                        new Object[] {new Integer(objnum), params});
+                        new Object[] {new Integer(objnum), params, pdf});
             return (PDFEncryption)obj;
         } catch (ClassNotFoundException e) {
             if (checkAvailableAlgorithms()) {
diff --git a/src/java/org/apache/fop/pdf/PDFEncryptionParams.java b/src/java/org/apache/fop/pdf/PDFEncryptionParams.java
index 9cc502c42..71dccd867 100644
--- a/src/java/org/apache/fop/pdf/PDFEncryptionParams.java
+++ b/src/java/org/apache/fop/pdf/PDFEncryptionParams.java
@@ -26,10 +26,17 @@ public class PDFEncryptionParams {
 
     private String userPassword = ""; //May not be null
     private String ownerPassword = ""; //May not be null
+
     private boolean allowPrint = true;
     private boolean allowCopyContent = true;
     private boolean allowEditContent = true;
     private boolean allowEditAnnotations = true;
+    private boolean allowFillInForms = true;
+    private boolean allowAccessContent = true;
+    private boolean allowAssembleDocument = true;
+    private boolean allowPrintHq = true;
+
+    private int encryptionLengthInBits = 40;
 
     /**
      * Creates a new instance.
@@ -61,6 +68,25 @@ public class PDFEncryptionParams {
     }
 
     /**
+     * Creates a copy of the given encryption parameters.
+     *
+     * @param source source encryption parameters
+     */
+    public PDFEncryptionParams(PDFEncryptionParams source) {
+        setUserPassword(source.getUserPassword());
+        setOwnerPassword(source.getOwnerPassword());
+        setAllowPrint(source.isAllowPrint());
+        setAllowCopyContent(source.isAllowCopyContent());
+        setAllowEditContent(source.isAllowEditContent());
+        setAllowEditAnnotations(source.isAllowEditAnnotations());
+        setAllowAssembleDocument(source.isAllowAssembleDocument());
+        setAllowAccessContent(source.isAllowAccessContent());
+        setAllowFillInForms(source.isAllowFillInForms());
+        setAllowPrintHq(source.isAllowPrintHq());
+        setEncryptionLengthInBits(source.getEncryptionLengthInBits());
+    }
+
+    /**
      * Indicates whether copying content is allowed.
      * @return true if copying is allowed
      */
@@ -93,6 +119,38 @@ public class PDFEncryptionParams {
     }
 
     /**
+     * Indicates whether revision 3 filling in forms is allowed.
+     * @return true if revision 3 filling in forms is allowed
+     */
+    public boolean isAllowFillInForms() {
+        return allowFillInForms;
+    }
+
+    /**
+     * Indicates whether revision 3 extracting text and graphics is allowed.
+     * @return true if revision 3 extracting text and graphics is allowed
+     */
+    public boolean isAllowAccessContent() {
+        return allowAccessContent;
+    }
+
+    /**
+     * Indicates whether revision 3 assembling document is allowed.
+     * @return true if revision 3 assembling document is allowed
+     */
+    public boolean isAllowAssembleDocument() {
+        return allowAssembleDocument;
+    }
+
+    /**
+     * Indicates whether revision 3 printing to high quality is allowed.
+     * @return true if revision 3 printing to high quality is allowed
+     */
+    public boolean isAllowPrintHq() {
+        return allowPrintHq;
+    }
+
+    /**
      * Returns the owner password.
      * @return the owner password, an empty string if no password applies
      */
@@ -133,7 +191,7 @@ public class PDFEncryptionParams {
     }
 
     /**
-     * Sets the persmission for printing.
+     * Sets the permission for printing.
      * @param allowPrint true if printing is allowed
      */
     public void setAllowPrint(boolean allowPrint) {
@@ -141,6 +199,38 @@ public class PDFEncryptionParams {
     }
 
     /**
+     * Sets whether revision 3 filling in forms is allowed.
+     * @param allowFillInForms true if revision 3 filling in forms is allowed.
+     */
+    public void setAllowFillInForms(boolean allowFillInForms) {
+        this.allowFillInForms = allowFillInForms;
+    }
+
+    /**
+     * Sets whether revision 3 extracting text and graphics is allowed.
+     * @param allowAccessContent true if revision 3 extracting text and graphics is allowed
+     */
+    public void setAllowAccessContent(boolean allowAccessContent) {
+        this.allowAccessContent = allowAccessContent;
+    }
+
+    /**
+     * Sets whether revision 3 assembling document is allowed.
+     * @param allowAssembleDocument true if revision 3 assembling document is allowed
+     */
+    public void setAllowAssembleDocument(boolean allowAssembleDocument) {
+        this.allowAssembleDocument = allowAssembleDocument;
+    }
+
+    /**
+     * Sets whether revision 3 printing to high quality is allowed.
+     * @param allowPrintHq true if revision 3 printing to high quality is allowed
+     */
+    public void setAllowPrintHq(boolean allowPrintHq) {
+        this.allowPrintHq = allowPrintHq;
+    }
+
+    /**
      * Sets the owner password.
      * @param ownerPassword The owner password to set, null or an empty String
      * if no password is applicable
@@ -166,4 +256,21 @@ public class PDFEncryptionParams {
         }
     }
 
+    /**
+     * Returns the encryption length.
+     * @return the encryption length
+     */
+    public int getEncryptionLengthInBits() {
+        return encryptionLengthInBits;
+    }
+
+    /**
+     * Sets the encryption length.
+     *
+     * @param encryptionLength the encryption length
+     */
+    public void setEncryptionLengthInBits(int encryptionLength) {
+        this.encryptionLengthInBits = encryptionLength;
+    }
+
 }
diff --git a/src/java/org/apache/fop/pdf/PDFObject.java b/src/java/org/apache/fop/pdf/PDFObject.java
index 09b8673a8..6dd0c800f 100644
--- a/src/java/org/apache/fop/pdf/PDFObject.java
+++ b/src/java/org/apache/fop/pdf/PDFObject.java
@@ -112,7 +112,7 @@ public abstract class PDFObject implements PDFWritable {
     }
 
     /**
-     * Returns the object's generation.
+     * Returns this object's generation.
      * @return the PDF Object generation
      */
     public int getGeneration() {