GH-238 document signing

core/core-awt/src/main/java/module-info.java

@@ -30,10 +30,14 @@
     exports org.icepdf.core.pobjects;
     exports org.icepdf.core.pobjects.acroform;
     exports org.icepdf.core.pobjects.acroform.signature;
+    exports org.icepdf.core.pobjects.acroform.signature.appearance;
     exports org.icepdf.core.pobjects.acroform.signature.certificates;
     exports org.icepdf.core.pobjects.acroform.signature.exceptions;
+    exports org.icepdf.core.pobjects.acroform.signature.handlers;
+    exports org.icepdf.core.pobjects.acroform.signature.utils;
     exports org.icepdf.core.pobjects.actions;
     exports org.icepdf.core.pobjects.annotations;
+    exports org.icepdf.core.pobjects.annotations.utils;
     exports org.icepdf.core.pobjects.fonts;
     exports org.icepdf.core.pobjects.graphics;
     exports org.icepdf.core.pobjects.graphics.commands;

core/core-awt/src/main/java/org/icepdf/core/pobjects/Catalog.java

@@ -35,7 +35,7 @@
  * class for convenience, but can also be accessed via the {@link PTrailer} class.
  * Useful information about the document can be extracted from the Catalog
  * Dictionary, such as PDF version information and Viewer Preferences.  All
- * Catalog dictionary properties can be accesed via the getEntries method.
+ * Catalog dictionary properties can be accessed via the getEntries method.
  * See section 3.6.1 of the PDF Reference version 1.6 for more information on
  * the properties available in the Catalog Object. </p>
  *
@@ -415,6 +415,23 @@ public InteractiveForm getInteractiveForm() {
         return interactiveForm;
     }
 
+    /**
+     * Gets the interactive form object that contains the form widgets for the given PDF.  This method should be
+     * called before adding new widgets.
+     *
+     * @return The interactive form object if it exists, if null a new dictionary is inserted into the document.
+     */
+    public InteractiveForm getOrCreateInteractiveForm() {
+        if (interactiveForm == null) {
+            interactiveForm = new InteractiveForm(library, new DictionaryEntries());
+            StateManager stateManager = library.getStateManager();
+            this.entries.put(ACRO_FORM_KEY, interactiveForm);
+            stateManager.addChange(new PObject(this, this.getPObjectReference()));
+            return interactiveForm;
+        }
+        return interactiveForm;
+    }
+
     /**
      * Returns a summary of the Catalog dictionary values.
      *

core/core-awt/src/main/java/org/icepdf/core/pobjects/Document.java

@@ -649,7 +649,7 @@ public long saveToOutputStream(OutputStream out, WriteMode writeMode) throws IOE
      *                       There are two possible entries, SCREEN and PRINT each with configurable
      *                       rendering hints settings.
      * @param pageBoundary   Constant specifying the page boundary to use when
-     *                       painting the page content. Typically use Page.BOUNDARY_CROPBOX.
+     *                       painting the page content. Typically, use Page.BOUNDARY_CROPBOX.
      * @param userRotation   Rotation factor, in degrees, to be applied to the rendered page.
      *                       Arbitrary rotations are not currently supported for this method,
      *                       so only the following values are valid: 0.0f, 90.0f, 180.0f, 270.0f.

core/core-awt/src/main/java/org/icepdf/core/pobjects/Form.java

@@ -18,6 +18,7 @@
 import org.icepdf.core.pobjects.graphics.ExtGState;
 import org.icepdf.core.pobjects.graphics.GraphicsState;
 import org.icepdf.core.pobjects.graphics.Shapes;
+import org.icepdf.core.pobjects.graphics.images.ImageStream;
 import org.icepdf.core.util.Library;
 import org.icepdf.core.util.parser.content.ContentParser;
 import org.icepdf.core.util.updater.callbacks.ContentStreamCallback;
@@ -28,6 +29,10 @@
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import static org.icepdf.core.pobjects.Resources.FONT_KEY;
+import static org.icepdf.core.pobjects.Resources.XOBJECT_KEY;
+import static org.icepdf.core.pobjects.annotations.FreeTextAnnotation.EMBEDDED_FONT_NAME;
+
 /**
  * Form XObject class. Not currently part of the public api.
  * <br>
@@ -140,7 +145,7 @@ private static AffineTransform getAffineTransform(List v) {
 
     /**
      * As of the PDF 1.2 specification, a resource entry is not required for
-     * a XObject and thus it needs to point to the parent resource to enable
+     * a XObject, thus it needs to point to the parent resource to enable
      * to correctly load the content stream.
      *
      * @param parentResource parent objects resourse when available.
@@ -212,6 +217,64 @@ public void setResources(Resources resources) {
         entries.put(RESOURCES_KEY, resources.getEntries());
     }
 
+    /**
+     * Add a Font resource to this Form's resource dictionary.  This is intended for new object only, can't guarantee
+     * this method will work as expected on an existing object.
+     *
+     * @param fontDictionary font dictionary to add as a resource
+     */
+    public void addFontResource(DictionaryEntries fontDictionary) {
+        StateManager stateManager = library.getStateManager();
+        org.icepdf.core.pobjects.fonts.Font newFont;
+        Resources formResources = getResources();
+        DictionaryEntries fontsDictionary = formResources.getFonts();
+        if (fontsDictionary == null) {
+            fontsDictionary = new DictionaryEntries();
+            formResources.entries.put(FONT_KEY, fontsDictionary);
+        }
+        if (formResources.getFont(EMBEDDED_FONT_NAME) == null) {
+            // set up a new font resource
+            newFont = new org.icepdf.core.pobjects.fonts.zfont.SimpleFont(library, fontDictionary);
+            newFont.setPObjectReference(stateManager.getNewReferenceNumber());
+            // create font entry
+            fontsDictionary.put(EMBEDDED_FONT_NAME, newFont.getPObjectReference());
+            // sync font resources with form object.
+            entries.put(RESOURCES_KEY, formResources.entries);
+        } else {
+            // reuse previously defined 'common' annotation font
+            newFont = formResources.getFont(EMBEDDED_FONT_NAME);
+            Reference reference = newFont.getPObjectReference();
+            newFont = new org.icepdf.core.pobjects.fonts.zfont.SimpleFont(library, fontDictionary);
+            newFont.setPObjectReference(reference);
+        }
+
+        // update hard reference to state manager and weak library reference.
+        stateManager.addChange(new PObject(newFont, newFont.getPObjectReference()), isNew);
+        library.addObject(newFont, newFont.getPObjectReference());
+        // make sure the form changes get picked up as well
+        stateManager.addChange(new PObject(this, getPObjectReference()), isNew);
+    }
+
+    /**
+     * Add an ImageStream to this Form's resource dictionary.  This is intended for new object only, can't guarantee
+     * this method will work as expected on an existing object.
+     *
+     * @param imageName   named image
+     * @param imageStream corresponding ImageStream data
+     */
+    public void addImageResource(Name imageName, ImageStream imageStream) {
+        Resources formResources = getResources();
+        DictionaryEntries xObjectsDictionary = formResources.getXObjects();
+        if (xObjectsDictionary == null) {
+            xObjectsDictionary = new DictionaryEntries();
+            formResources.entries.put(XOBJECT_KEY, xObjectsDictionary);
+        }
+        // sync form resources with form object.
+        entries.put(RESOURCES_KEY, formResources.entries);
+        xObjectsDictionary.put(imageName, imageStream.getPObjectReference());
+        StateManager stateManager = library.getStateManager();
+        stateManager.addChange(new PObject(this, getPObjectReference()), isNew);
+    }
 
     /**
      * Gets the shapes that where parsed from the content stream.

core/core-awt/src/main/java/org/icepdf/core/pobjects/HexStringObject.java

@@ -67,6 +67,21 @@ public static HexStringObject createHexString(String literalstring) {
         return new HexStringObject(hexString.toString());
     }
 
+    public static String encodeHexString(byte[] byteArray) {
+        StringBuffer hexStringBuffer = new StringBuffer();
+        for (int i = 0; i < byteArray.length; i++) {
+            hexStringBuffer.append(byteToHex(byteArray[i]));
+        }
+        return hexStringBuffer.toString();
+    }
+
+    private static String byteToHex(byte num) {
+        char[] hexDigits = new char[2];
+        hexDigits[0] = Character.forDigit((num >> 4) & 0xF, 16);
+        hexDigits[1] = Character.forDigit((num & 0xF), 16);
+        return new String(hexDigits);
+    }
+
     /**
      * Encodes the given contents string into a 4 byte hex string.  This allows us to easily account for
      * mixed encoding of 2-byte and 4 byte string content.
@@ -281,7 +296,8 @@ private static StringBuilder normalizeHex(StringBuilder hex, int step) {
         if (step == 2) {
             // pre append 0's to uneven length, be careful as the 0020 isn't the same as 2000
             if (length % 2 != 0) {
-                hex = new StringBuilder("0").append(hex);
+                // this was done for variable byte font encoding,  this seems risky to preappend, pulling
+                hex = hex.append("0");//new StringBuilder("0").append(hex);
             }
         }
         if (step == 4) {

core/core-awt/src/main/java/org/icepdf/core/pobjects/Resources.java

@@ -51,8 +51,8 @@ private static synchronized int getUniqueId() {
     private static final Logger logger =
             Logger.getLogger(Resources.class.toString());
 
-    final DictionaryEntries fonts;
-    final DictionaryEntries xobjects;
+    DictionaryEntries fonts;
+    DictionaryEntries xobjects;
     final DictionaryEntries colorspaces;
     final DictionaryEntries patterns;
     final DictionaryEntries shading;
@@ -71,6 +71,9 @@ public Resources(Library l, DictionaryEntries h) {
     }
 
     public DictionaryEntries getFonts() {
+        if (fonts == null) {
+            fonts = library.getDictionary(entries, FONT_KEY);
+        }
         return fonts;
     }
 
@@ -213,6 +216,9 @@ public Object getXObject(Name s) {
     }
 
     public DictionaryEntries getXObjects() {
+        if (xobjects == null) {
+            xobjects = library.getDictionary(entries, XOBJECT_KEY);
+        }
         return xobjects;
     }
 

core/core-awt/src/main/java/org/icepdf/core/pobjects/StateManager.java

@@ -43,6 +43,7 @@ public class StateManager {
     private final CrossReferenceRoot crossReferenceRoot;
 
     private final AtomicInteger nextReferenceNumber;
+    private final AtomicInteger nextImageNumber;
 
     // snapshot of currently saved changes
     private Map<Reference, StateManager.Change> savedChangesSnapshot = new HashMap<>();
@@ -61,6 +62,8 @@ public StateManager(CrossReferenceRoot crossReferenceRoot) {
         // thus the next available number.
         nextReferenceNumber = new AtomicInteger();
         nextReferenceNumber.set(this.crossReferenceRoot.getNextAvailableReferenceNumber());
+        // named image reference count
+        nextImageNumber = new AtomicInteger((int) (Math.random() * 1000));
     }
 
     /**
@@ -75,6 +78,17 @@ public Reference getNewReferenceNumber() {
         return new Reference(nextReferenceNumber.getAndIncrement(), 0);
     }
 
+    /**
+     * Gets an image number to be used when generating image references.  The initial value is randomly
+     * generated and incremented for each addition image added to the document.  There should be very little
+     * chance that signature would have the same name.
+     *
+     * @return unique image number for building images names
+     */
+    public int getNextImageNumber() {
+        return nextImageNumber.getAndIncrement();
+    }
+
     /**
      * Add a new PObject containing changed data to the cache.
      *
@@ -206,6 +220,12 @@ public CrossReferenceRoot getCrossReferenceRoot() {
         return crossReferenceRoot;
     }
 
+    /**
+     * Checks to see if any redaction annotations are present in the changes.  This is used to determine if
+     * the document has redactions that need to be burned in.
+     *
+     * @return true if redactions are present, false otherwise.
+     */
     public boolean hasRedactions() {
         if (changes.isEmpty()) return false;
         Collection<Change> changesValues = changes.values();

core/core-awt/src/main/java/org/icepdf/core/pobjects/acroform/DocMDPTransferParam.java

@@ -90,6 +90,10 @@ public int getPermissions() {
      * @return always returns 1.2 as a name.
      */
     public Name getVersion() {
+        return DocMDPTransferParam.getDocMDPVersion();
+    }
+
+    public static Name getDocMDPVersion() {
         return new Name("1.2");
     }
 

core/core-awt/src/main/java/org/icepdf/core/pobjects/acroform/InteractiveForm.java

@@ -16,11 +16,13 @@
 package org.icepdf.core.pobjects.acroform;
 
 import org.icepdf.core.pobjects.*;
+import org.icepdf.core.pobjects.annotations.AbstractWidgetAnnotation;
 import org.icepdf.core.pobjects.annotations.SignatureWidgetAnnotation;
 import org.icepdf.core.util.Library;
 import org.icepdf.core.util.Utils;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.logging.Logger;
 
@@ -206,6 +208,36 @@ public synchronized void init() {
         }
     }
 
+    public void addField(Object field) {
+        if (!(field instanceof AbstractWidgetAnnotation)) {
+            throw new IllegalStateException("Field must be an AbstractWidgetAnnotation");
+        }
+        if (fields == null) {
+            fields = new ArrayList<>();
+            fields.add(field);
+            entries.put(FIELDS_KEY,
+                    new ArrayList<>(Arrays.asList(((AbstractWidgetAnnotation) field).getPObjectReference())));
+        } else {
+            fields.add(field);
+            List<Reference> fieldReferences = (List<Reference>) library.getObject(entries, FIELDS_KEY);
+            fieldReferences.add(((AbstractWidgetAnnotation) field).getPObjectReference());
+        }
+        // mark the catalog as changed, this object is always contained in the catalog as a dictionary, it
+        // should never be an indirect reference.
+        Catalog catalog = library.getCatalog();
+        StateManager stateManager = library.getStateManager();
+        stateManager.addChange(new PObject(catalog, catalog.getPObjectReference()));
+    }
+
+    public void removeField(AbstractWidgetAnnotation field) {
+        if (fields != null) {
+            fields.remove(field);
+            List<Reference> fieldReferences = (List<Reference>) library.getObject(entries, FIELDS_KEY);
+            fieldReferences.remove((field).getPObjectReference());
+        }
+    }
+
+
     /**
      * Gets the fields associated with this form.
      *
@@ -216,7 +248,8 @@ public ArrayList<Object> getFields() {
     }
 
     /**
-     * Gets the signature fields associated with this form.  A new array that references the forms signature annotations.
+     * Gets the signature fields associated with this form.  A new array that references the forms signature
+     * annotations.
      * If no fields are found an empty list is returned.
      *
      * @return a list of form signature objects.
@@ -351,7 +384,8 @@ public String getDefaultVariableTextDAField() {
     /**
      * Ges the default variable text quadding rule.
      *
-     * @return integer represented by VariableTextFieldDictionary.QUADDING_LEFT_JUSTIFIED, VariableTextFieldDictionary.QUADDING_CENTERED or
+     * @return integer represented by VariableTextFieldDictionary.QUADDING_LEFT_JUSTIFIED,
+     * VariableTextFieldDictionary.QUADDING_CENTERED or
      * VariableTextFieldDictionary.QUADDING_RIGHT_JUSTIFIED.
      */
     public int getDefaultVariableTextQField() {