Assinar PDF digitalmente (Usando certificado A1)

JavaC Membro Membro desde: 04/11/2013 14:56:24 Mensagens: 2 Offline

Eu consegui dar uma pequena implementada nessa classe para assinar XML Nfe. Gostaria dentro dessa mesma idéia, assinar documentos PDF. Segue a classe na qual quero me apoiar:

public class AssinarXMLsCertfificadoA1 {  
    private static final String INFINUT = "infInut";  
    private static final String INFCANC = "infCanc";  
    private static final String NFE = "NFe";  
  
    private PrivateKey privateKey;  
    private KeyInfo keyInfo;  
  
    public static void main(String[] args) {  
        try {
        	/* Parâmetros */
            String caminhoDoCertificadoDoCliente = "C:/certificado.pfx";  
            String senhaDoCertificadoDoCliente = "qwer1234";  
			String fileEnviNFe = "C:/teste-NFe.xml";
			String fileCancNFe = "C:/teste-NFe.xml";
			String fileInutNFe = "C:/teste-NFe.xml";
            String arquivoXmlNovo = "C:/teste-NFe-novo.xml";
			String tipo = "1";			
			
			AssinarXMLsCertfificadoA1 assinarXMLsCertfificadoA1 = new AssinarXMLsCertfificadoA1(); 
			
			/* Operação 
			* '1' - NFE 
			* '2' - CANCELAMENTO 
			* '3' - INUTILIZAÇÃO 
			*/  
			
			if (tipo.equals("1")) {
				
				/* Assinando o XML de Lote da NF-e */ 
				String xmlEnviNFe = lerXML(fileEnviNFe);
				
				String xmlEnviNFeAssinado = assinarXMLsCertfificadoA1.assinaEnviNFe(  
						xmlEnviNFe, caminhoDoCertificadoDoCliente, senhaDoCertificadoDoCliente);
				
				saveXml(xmlEnviNFeAssinado, arquivoXmlNovo);
				
			} else if (tipo.equals("2")) {  
				
				/* Assinando o XML de Cancelamento da NF-e */ 
				String xmlCancNFe = lerXML(fileCancNFe); 
				
				String xmlCancNFeAssinado = assinarXMLsCertfificadoA1.assinaCancNFe(  
                    xmlCancNFe, caminhoDoCertificadoDoCliente, senhaDoCertificadoDoCliente);
				
				saveXml(xmlCancNFeAssinado, arquivoXmlNovo);
				
			} else if (tipo.equals("3")) {

/* Assinando o XML de Inutilizacao da NF-e	*/
				String xmlInutNFe = lerXML(fileInutNFe);
				
				String xmlInutNFeAssinado = assinarXMLsCertfificadoA1.assinaInutNFe(  
                    xmlInutNFe, caminhoDoCertificadoDoCliente, senhaDoCertificadoDoCliente);
				
				saveXml(xmlInutNFeAssinado, arquivoXmlNovo);
			}
			
  
        } catch (Exception e) {  
            error("| " + e.toString());  
        }  
    }  
  
    /* Assinatura do XML de Lote da NF-e utilizando Certificado  */
    public String assinaEnviNFe(String xml, String certificado, String senha)  
            throws Exception {
        Document document = documentFactory(xml);
        XMLSignatureFactory signatureFactory = XMLSignatureFactory.getInstance("DOM");  
        ArrayList<Transform> transformList = signatureFactory(signatureFactory);  
        loadCertificates(certificado, senha, signatureFactory);  
        for (int i = 0; i < document.getDocumentElement().getElementsByTagName(NFE).getLength(); i++) {
        	assinarNFe(signatureFactory, transformList, privateKey, keyInfo, document, i);
        }
        return outputXML(document);  
    }  
  
    /* Assinatura do XML de Cancelamento da NF-e utilizando Certificado  */  
    public String assinaCancNFe(String xml, String certificado, String senha) throws Exception {  
        return assinaCancelametoInutilizacao(xml, certificado, senha, INFCANC);  
    }  
  
    /* Assinatura do XML de Inutilizacao de sequenciais da NF-e utilizando */ 
    public String assinaInutNFe(String xml, String certificado, String senha) throws Exception {  
        return assinaCancelametoInutilizacao(xml, certificado, senha, INFINUT);  
    }  
  
    private void assinarNFe(XMLSignatureFactory fac,  
            ArrayList<Transform> transformList, PrivateKey privateKey,  
            KeyInfo ki, Document document, int indexNFe) throws Exception {  
        NodeList elements = document.getElementsByTagName("infNFe");  
        org.w3c.dom.Element el = (org.w3c.dom.Element) elements.item(indexNFe);  
        el.setIdAttribute("Id", true);
        String id = el.getAttribute("Id");    
        Reference ref = fac.newReference("#" + id,  
                fac.newDigestMethod(DigestMethod.SHA1, null), transformList,  
                null, null);  
  
        SignedInfo si = fac.newSignedInfo(fac.newCanonicalizationMethod(  
                CanonicalizationMethod.INCLUSIVE,  
                (C14NMethodParameterSpec) null), fac  
                .newSignatureMethod(SignatureMethod.RSA_SHA1, null),  
                Collections.singletonList(ref));  
  
        XMLSignature signature = fac.newXMLSignature(si, ki);  
  
        DOMSignContext dsc = new DOMSignContext(privateKey,   
                document.getDocumentElement().getElementsByTagName(NFE).item(indexNFe));  
        signature.sign(dsc);  
    }  
  
    private String assinaCancelametoInutilizacao(String xml,  
            String certificado, String senha, String tagCancInut)  
            throws Exception {  
        Document document = documentFactory(xml);  
  
        XMLSignatureFactory signatureFactory = XMLSignatureFactory  
                .getInstance("DOM");  
        ArrayList<Transform> transformList = signatureFactory(signatureFactory);  
        loadCertificates(certificado, senha, signatureFactory);  
  
        NodeList elements = document.getElementsByTagName(tagCancInut);  
        org.w3c.dom.Element el = (org.w3c.dom.Element) elements.item(0);  
        el.setIdAttribute("Id", true);
        String id = el.getAttribute("Id");  
  
        Reference ref = signatureFactory.newReference("#" + id,  
                signatureFactory.newDigestMethod(DigestMethod.SHA1, null),  
                transformList, null, null);  
  
        SignedInfo si = signatureFactory.newSignedInfo(signatureFactory  
                .newCanonicalizationMethod(CanonicalizationMethod.INCLUSIVE,  
                        (C14NMethodParameterSpec) null), signatureFactory  
                .newSignatureMethod(SignatureMethod.RSA_SHA1, null),  
                Collections.singletonList(ref));  
  
        XMLSignature signature = signatureFactory.newXMLSignature(si, keyInfo);  
  
        DOMSignContext dsc = new DOMSignContext(privateKey, document.getFirstChild());  
        signature.sign(dsc);  
  
        return outputXML(document);  
    }
  
    private ArrayList<Transform> signatureFactory(  
            XMLSignatureFactory signatureFactory)  
            throws NoSuchAlgorithmException, InvalidAlgorithmParameterException {  
        ArrayList<Transform> transformList = new ArrayList<Transform>();  
        TransformParameterSpec tps = null;  
        Transform envelopedTransform = signatureFactory.newTransform(  
                Transform.ENVELOPED, tps);  
        Transform c14NTransform = signatureFactory.newTransform(  
                "http://www.w3.org/TR/2001/REC-xml-c14n-20010315", tps);  
  
        transformList.add(envelopedTransform);  
        transformList.add(c14NTransform);  
        return transformList;  
    }  
  
    private Document documentFactory(String xml) throws SAXException,  
            IOException, ParserConfigurationException {  
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();  
        factory.setNamespaceAware(true);  
        Document document = factory.newDocumentBuilder().parse(  
                new ByteArrayInputStream(xml.getBytes()));  
        return document;  
    }  
  
    private void loadCertificates(String certificado, String senha,  
            XMLSignatureFactory signatureFactory) throws Exception {  
  
        InputStream entrada = new FileInputStream(certificado);  
        KeyStore ks = KeyStore.getInstance("pkcs12");  
        try {  
            ks.load(entrada, senha.toCharArray());  
        } catch (IOException e) {  
            throw new Exception("Senha do Certificado Digital incorreta ou Certificado inválido.");  
        }  
  
        KeyStore.PrivateKeyEntry pkEntry = null;  
        Enumeration<String> aliasesEnum = ks.aliases();  
        while (aliasesEnum.hasMoreElements()) {  
            String alias = (String) aliasesEnum.nextElement();  
            if (ks.isKeyEntry(alias)) {  
                pkEntry = (KeyStore.PrivateKeyEntry) ks.getEntry(alias,  
                        new KeyStore.PasswordProtection(senha.toCharArray()));  
                privateKey = pkEntry.getPrivateKey();  
                break;  
            }  
        }  
  
        X509Certificate cert = (X509Certificate) pkEntry.getCertificate();  
  
        KeyInfoFactory keyInfoFactory = signatureFactory.getKeyInfoFactory();  
        List<X509Certificate> x509Content = new ArrayList<X509Certificate>();  
  
        x509Content.add(cert);  
        X509Data x509Data = keyInfoFactory.newX509Data(x509Content);  
        keyInfo = keyInfoFactory.newKeyInfo(Collections.singletonList(x509Data));  
    }  
  
    private String outputXML(Document doc) throws TransformerException {  
        ByteArrayOutputStream os = new ByteArrayOutputStream();  
        TransformerFactory tf = TransformerFactory.newInstance();  
        Transformer trans = tf.newTransformer();  
        trans.transform(new DOMSource(doc), new StreamResult(os));  
        String xml = os.toString();  
        if ((xml != null) && (!"".equals(xml))) {  
            xml = xml.replaceAll("\\r\\n", "");  
            xml = xml.replaceAll(" standalone=\"no\"", "");  
        }  
        
        return xml;  
    }  
  
    private static String lerXML(String fileXML) throws IOException {  
        String linha = "";  
        StringBuilder xml = new StringBuilder();  
  
        BufferedReader in = new BufferedReader(new InputStreamReader(  
                new FileInputStream(fileXML)));  
        while ((linha = in.readLine()) != null) {  
            xml.append(linha);  
        }  
        in.close();  
  
        return xml.toString();  
    }  
  
	private static void saveXml(String xmlEnviNFeAssinado, String arquivoXmlNovo) throws IOException {
	    Writer file = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(arquivoXmlNovo),"ISO-8859-1"));  
	    file.write(xmlEnviNFeAssinado);  
	    file.close();  
	    
	    JOptionPane.showMessageDialog(null,"XML ''"+ arquivoXmlNovo +"'' assinado com sucesso!");
    }
    
    private static void error(String error) {  
        System.out.println("| ERROR: " + error);
        JOptionPane.showMessageDialog(null,"Erro ao assinar XML. Erro: " + error);
    }

private static void info(String info) {  
        System.out.println("| INFO: " + info);  
    }  
}

I ae pessoal, alguém ai com algum exemplo para assinar PDF com A1?

Moderador Membro desde: 11/03/2014 10:10:20 Mensagens: 447 Offline

Como assim "Assinar PDF" ?

tiagoberga wrote:Como assim "Assinar PDF" ?

Boa tarde Tiago,

Voltando ao assunto preciso desenvolver algo parecido com isso:

http://www.qualisoft.com.br/produto-desksigner.asp?gclid=CjwKEAiAi52mBRDkq5bX0vq1-RQSJAAq_7IG2rpSnClpfcGgcxDtQvCra05zOVqqDY-b3ZVtY81RGBoCcVXw_wcB

Moderador Membro desde: 11/03/2014 10:10:20 Mensagens: 447 Offline

caramba, tardelli13 nunca ouvi falar nisso cara, conseguiu encontrar alguma coisa?

Encontrei, da pra fazer usando as bibliotecas do IText - http://itextpdf.com/

assim que conseguir desenvolver um bom exemplo eu posto aqui

Conseguiu implementar o exemplo? Estou com a mesma necessidade.

Obrigado desde já.

JavaC Membro Membro desde: 01/03/2016 14:09:53 Mensagens: 1 Offline

tardelli13 Você conseguiu um exemplo?

Consegui fazer utilizando o iText irei postar o exemplo.

JavaC Membro Membro desde: 12/04/2016 12:16:42 Mensagens: 3 Offline

Olá jeroqueiroz, por gentileza você tem como disponibilizar como você assinou o pdf com o certificado A1?

Esta é minha classe de testes para assinatura de PDF a qual montei os métodos que precisei. Tudo que utilizei esta nela.

Ela é uma classe do livro iText in Action o qual usei como base para construir minha assinatura.

import java.io.*;
import java.security.*;
import java.security.cert.Certificate;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Properties;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import com.itextpdf.text.*;
import com.itextpdf.text.pdf.*;

public class Signatures {

/** The resulting PDF */
	// public static String ORIGINAL = "/Users/jeremias/Downloads/hello.pdf";
	public static String ORIGINAL = "/Users/jeremias/Downloads/YouTube.pdf";
	/** The resulting PDF */
	// public static String SIGNED1 = "/Users/jeremias/Downloads/signature_1.pdf";
	public static String SIGNED1 = "/Users/jeremias/Downloads/signature_1.pdf";
	/** The resulting PDF */
	public static String SIGNED2 = "r/Users/jeremias/Downloads/signature_2.pdf";
	/** Info after verification of a signed PDF */
	public static String VERIFICATION = "/Users/jeremias/Downloads/verify.txt";
	/** The resulting PDF */
	public static String REVISION = "/Users/jeremias/Downloads/revision_1.pdf";

/**
	 * A properties file that is PRIVATE. You should make your own properties file and adapt this line.
	 */
	// TODO public static String PATH = "/home/jeremias/Downloads/key.properties";
	/** Some properties used when signing. */
	public static Properties properties = new Properties();
	/** One of the resources. */
	public static final String RESOURCE = "resources/img/logo.gif";

/**
	 * Creates a PDF document.
	 *
	 * @param filename
	 *            the path to the new PDF document
	 * @throws DocumentException
	 * @throws IOException
	 */
	public void createPdf(String filename) throws IOException, DocumentException {
		Document document = new Document();
		PdfWriter.getInstance(document, new FileOutputStream(filename));
		document.open();
		document.add(new Paragraph("Hello World!"));
		document.close();
	}

/**
	 * Manipulates a PDF file src with the file dest as result
	 *
	 * @param src
	 *            the original PDF
	 * @param dest
	 *            the resulting PDF
	 * @throws IOException
	 * @throws DocumentException
	 * @throws GeneralSecurityException
	 */
	public void signPdfFirstTime(String src, String dest) throws IOException, DocumentException, GeneralSecurityException {
		// TODO properties.getProperty("PRIVATE");
		String path = "/Users/jeremias/Downloads/adigital.pfx";
		String keystore_password = "12345"; // TODO properties.getProperty("PASSWORD");
		String key_password = "12345"; // TODO properties.getProperty("PASSWORD");
		KeyStore ks = KeyStore.getInstance("pkcs12", "BC");
		ks.load(new FileInputStream(path), keystore_password.toCharArray());
		String alias = ks.aliases().nextElement();
		PrivateKey key = (PrivateKey) ks.getKey(alias, key_password.toCharArray());
		Certificate[] chain = ks.getCertificateChain(alias);
		PdfReader reader = new PdfReader(src);
		FileOutputStream os = new FileOutputStream(dest);
		PdfStamper stamper = PdfStamper.createSignature(reader, os, '\0');

PdfSignatureAppearance appearance = stamper.getSignatureAppearance();
		appearance.setCrypto(key, chain, null, PdfSignatureAppearance.WINCER_SIGNED);
		// appearance.setImage(Image.getInstance(RESOURCE));
		appearance.setReason("Assinatura Digital.");
		appearance.setLocation("Sistema Doc Digital");
		appearance.setSignDate(Calendar.getInstance());
		// appearance.setVisibleSignature(new Rectangle(250, 732, 144, 780), 1, "first");
		appearance.setVisibleSignature(new Rectangle(10, 0, 300, 30), 1, "Inicio");
		stamper.close();
	}

/**
	 * Manipulates a PDF file src with the file dest as result
	 *
	 * @param src
	 *            the original PDF
	 * @param dest
	 *            the resulting PDF
	 * @throws IOException
	 * @throws DocumentException
	 * @throws GeneralSecurityException
	 */
	public void signPdfSecondTime(String src, String dest) throws IOException, DocumentException, GeneralSecurityException {
		String path = "resources/encryption/.keystore";
		String keystore_password = "f00b4r";
		String key_password = "f1lmf3st";
		String alias = "foobar";
		KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
		ks.load(new FileInputStream(path), keystore_password.toCharArray());
		PrivateKey key = (PrivateKey) ks.getKey(alias, key_password.toCharArray());
		Certificate[] chain = ks.getCertificateChain(alias);
		PdfReader reader = new PdfReader(src);
		FileOutputStream os = new FileOutputStream(dest);
		PdfStamper stamper = PdfStamper.createSignature(reader, os, '\0', null, true);
		PdfSignatureAppearance appearance = stamper.getSignatureAppearance();
		appearance.setCrypto(key, chain, null, PdfSignatureAppearance.WINCER_SIGNED);
		appearance.setReason("I'm approving this.");
		appearance.setLocation("Foobar");
		appearance.setVisibleSignature(new Rectangle(160, 732, 232, 780), 1, "second");
		stamper.close();

}

/**
	 * Verifies the signatures of a PDF we've signed twice.
	 *
	 * @throws GeneralSecurityException
	 * @throws IOException
	 */
	public void verifySignatures() throws GeneralSecurityException, IOException {
		KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
		ks.load(null, null);
		CertificateFactory cf = CertificateFactory.getInstance("X509");
		FileInputStream is1 = new FileInputStream(properties.getProperty("ROOTCERT"));
		X509Certificate cert1 = (X509Certificate) cf.generateCertificate(is1);
		ks.setCertificateEntry("cacert", cert1);
		FileInputStream is2 = new FileInputStream("resources/encryption/digitaldocs.cer");
		X509Certificate cert2 = (X509Certificate) cf.generateCertificate(is2);
		ks.setCertificateEntry("digitaldocs", cert2);

PrintWriter out = new PrintWriter(new FileOutputStream(VERIFICATION));
		PdfReader reader = new PdfReader(SIGNED2);
		AcroFields af = reader.getAcroFields();
		ArrayList<String> names = af.getSignatureNames();
		for (String name : names) {
			out.println("Signature name: " + name);
			out.println("Signature covers whole document: " + af.signatureCoversWholeDocument(name));
			out.println("Document revision: " + af.getRevision(name) + " of " + af.getTotalRevisions());
			PdfPKCS7 pk = af.verifySignature(name);
			Calendar cal = pk.getSignDate();
			Certificate[] pkc = pk.getCertificates();
			out.println("Subject: " + PdfPKCS7.getSubjectFields(pk.getSigningCertificate()));
			out.println("Revision modified: " + !pk.verify());
			Object fails[] = PdfPKCS7.verifyCertificates(pkc, ks, null, cal);
			if (fails == null) {
				out.println("Certificates verified against the KeyStore");
			} else {
				out.println("Certificate failed: " + fails[1]);
			}
		}
		out.flush();
		out.close();
	}

/**
	 * Extracts the first revision of a PDF we've signed twice.
	 *
	 * @throws IOException
	 */
	public void extractFirstRevision() throws IOException {
		PdfReader reader = new PdfReader(SIGNED2);
		AcroFields af = reader.getAcroFields();
		FileOutputStream os = new FileOutputStream(REVISION);
		byte bb[] = new byte[1028];
		InputStream ip = af.extractRevision("first");
		int n = 0;
		while ((n = ip.read(bb)) > 0) {
			os.write(bb, 0, n);
		}
		os.close();
		ip.close();
	}

/**
	 * Main method.
	 *
	 * @param args
	 *            no arguments needed
	 * @throws DocumentException
	 * @throws IOException
	 * @throws GeneralSecurityException
	 */
	public static void main(String[] args) throws IOException, DocumentException, GeneralSecurityException {
		Security.addProvider(new BouncyCastleProvider());
		// TODO properties.load(new FileInputStream(PATH));
		Signatures signatures = new Signatures();
		// signatures.createPdf(ORIGINAL);
		// signatures.signPdfFirstTime(ORIGINAL, SIGNED1);
		// signatures.signPdfSecondTime(SIGNED1, SIGNED2);
		// signatures.verifySignatures();
		// signatures.extractFirstRevision();
		signatures.assinarPdfTodasPaginas("/Users/jeremias/Downloads/YouTube.pdf", "/Users/jeremias/Downloads/Manual_Ass.pdf");
	}

public void assinarPdfTodasPaginas(String src, String dest) throws IOException, DocumentException, GeneralSecurityException {

String path = "/Users/jeremias/Documents/DEVELOPMENT/PROJETOS/NotaFiscalEletronica/CERTIFICADOS/adigital.p12";
		String keystore_password = "123456";
		String key_password = "123456";
		// KeyStore ks = KeyStore.getInstance("pkcs12", "BC");
		// ks.load(new FileInputStream(path), keystore_password.toCharArray());

KeyStore ks = KeyStore.getInstance("PKCS12");
		ks.load(new ByteArrayInputStream(getBytesFromInputStream(new FileInputStream(path))), keystore_password.toCharArray());
		String alias = ks.aliases().nextElement();
		PrivateKey key = (PrivateKey) ks.getKey(alias, key_password.toCharArray());
		Certificate[] chain = ks.getCertificateChain(alias);

// Get the first time signed pdf
		PdfReader reader = new PdfReader(src);
		ByteArrayOutputStream out = new ByteArrayOutputStream();

reader = new PdfReader(reader);
		// work with new revision each time
		PdfStamper stp1 = new PdfStamper(reader, out, '\3', true);

PdfFormField sig = PdfFormField.createSignature(stp1.getWriter());
		sig.setWidget(new Rectangle(10, 0, 300, 30), null);
		sig.setFlags(PdfAnnotation.FLAGS_PRINT);
		sig.put(PdfName.DA, new PdfString("/Helv 0 Tf 0 g"));
		sig.setFieldName("Signature4");
		sig.setPage(1);

// Attached the blank signature field to the existing document
		// stp1.addAnnotation(sig, 1);
		// stp1.addAnnotation(sig, 2);
		for (int p = 1; p <= reader.getNumberOfPages(); p++) {
			stp1.addAnnotation(sig, p);
		}

stp1.close();
		out.close();

FileOutputStream fout = new FileOutputStream(dest);

reader = new PdfReader(out.toByteArray());

// Fill the new signature fields in the correct pdf revision
		PdfStamper stp = PdfStamper.createSignature(reader, fout, '\3', null, true);
		PdfSignatureAppearance sap = stp.getSignatureAppearance();
		sap.setCrypto(key, chain, null, PdfSignatureAppearance.WINCER_SIGNED);

sap.setReason("RAZON");
		sap.setLocation("UBICACION");
		sap.setSignDate(Calendar.getInstance());

// sap.setLayer2Text("Texto");
		// sap.setAcro6Layers(true);
		// Set visible signature field
		sap.setVisibleSignature("Signature4");

// Close PdfStamper and output
		stp.close();
		fout.close();
	}

public static byte[] getBytesFromInputStream(InputStream is) throws IOException {
		try (ByteArrayOutputStream os = new ByteArrayOutputStream();) {
			byte[] buffer = new byte[0xFFFF];

for (int len; (len = is.read(buffer)) != -1;) {
				os.write(buffer, 0, len);
			}
			os.flush();
			return os.toByteArray();
		}
	}

}

JavaC Membro Membro desde: 12/04/2016 12:16:42 Mensagens: 3 Offline

Vou testar, muito obrigado!

JavaC Membro Membro desde: 12/04/2016 12:16:42 Mensagens: 3 Offline

Olá bom dia,
implementei da forma como você falou, mas estou recebendo uma exception que acredito que seja por causa das versões das bibliotecas que estou utilizando. Esses erros tem haver com as veroes das libs? Quais as versões das bibliotecas que você utilizou em seu projeto?
meu codigo:

package testeassinaturas;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.Security;
import java.security.cert.Certificate;
import java.util.Calendar;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import com.itextpdf.text.DocumentException;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfSignatureAppearance;
import com.itextpdf.text.pdf.PdfStamper;

public class Signatures {
	
	
	
    public static String ORIGINAL = "/home/ricardo/text.pdf";  
    public static String SIGNED1 = "/home/ricardo/signature_1.pdf";  
    
    
    
    public void signPdfFirstTime(String src, String dest) throws IOException, DocumentException, GeneralSecurityException {  
        String path = "/home/ricardo/Downloads/Associacao.pfx";  
        String keystore_password = "associacao"; 
        String key_password = "associacao";
        KeyStore ks = KeyStore.getInstance("pkcs12", "BC");  
        
        ks.load(new FileInputStream(path), keystore_password.toCharArray());  
        String alias = ks.aliases().nextElement();  
        PrivateKey key = (PrivateKey) ks.getKey(alias, key_password.toCharArray()); 
        Certificate[] chain = ks.getCertificateChain(alias); 
        PdfReader reader = new PdfReader(src);  
        FileOutputStream os = new FileOutputStream(dest);  
        PdfStamper stamper = PdfStamper.createSignature(reader, os, '\0',null,true);  
        PdfSignatureAppearance appearance = stamper.getSignatureAppearance();  
        appearance.setCrypto(key, chain, null, PdfSignatureAppearance.WINCER_SIGNED);   
        appearance.setReason("Assinatura Digital.");  
        appearance.setLocation("Sistema Doc Digital");  
        appearance.setSignDate(Calendar.getInstance());  
        appearance.setVisibleSignature(new com.itextpdf.text.Rectangle(10, 0, 300, 30), 1, "Inicio");  
        stamper.close();  
    }  
    
    
    public static void main(String[] args) {
		try {
			
	        Security.addProvider(new BouncyCastleProvider());  
			Signatures signatures = new Signatures();
			signatures.signPdfFirstTime(ORIGINAL, SIGNED1);
		} catch (IOException | DocumentException | GeneralSecurityException e) {
	
			e.printStackTrace();
		}
	}
}

A exception que estou recebendo é

estou utilizando iText 5.0.6
bcpkix-jdk15on-1.50.jar
bcprov-jdk15on-1.50.jar

Segue anexo.

Esta cpkix-jdk15on-1.50.jar não consta no Projeto.