Inspect digital signatures
getn2fromsig
JAVA
JAVA
/*
* Example written by Bruno Lowagie.
*/
package sandbox.security;
import com.itextpdf.text.pdf.AcroFields;
import com.itextpdf.text.pdf.AcroFields.Item;
import com.itextpdf.text.pdf.PRStream;
import com.itextpdf.text.pdf.PdfDictionary;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfStream;
import java.io.IOException;
/**
*
* @author Bruno Lowagie (iText Software)
*/
public class GetN2fromSig {
public static final String SRC = "resources/pdfs/signature_n2.pdf";
public static void main(String[] args) throws IOException {
PdfReader reader = new PdfReader(SRC);
AcroFields fields = reader.getAcroFields();
Item item = fields.getFieldItem("Signature1");
PdfDictionary widget = item.getWidget(0);
PdfDictionary ap = widget.getAsDict(PdfName.AP);
PdfStream normal = ap.getAsStream(PdfName.N);
PdfDictionary resources = normal.getAsDict(PdfName.RESOURCES);
PdfDictionary xobject = resources.getAsDict(PdfName.XOBJECT);
PdfStream frm = xobject.getAsStream(PdfName.FRM);
PdfDictionary res = frm.getAsDict(PdfName.RESOURCES);
PdfDictionary xobj = res.getAsDict(PdfName.XOBJECT);
PRStream n2 = (PRStream) xobj.getAsStream(PdfName.N2);
byte[] stream = PdfReader.getStreamBytes(n2);
System.out.println(new String(stream));
}
}