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.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.Properties;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfStamper;
import com.itextpdf.text.pdf.PdfWriter;
public class EncryptWithCertificate {
/** The resulting PDF */
public static String RESULT1 = "c:/results/part1/chapter01/certificate_encryption.pdf";
/** The resulting PDF */
public static String RESULT2 = "c:/results/part1/chapter01/certificate_decrypted.pdf";
/** The resulting PDF */
public static String RESULT3 = "c:/results/part1/chapter01/certificate_encrypted.pdf";
/**
* A properties file that is PRIVATE.
* You should make your own properties file and adapt this line.
*/
public static String PATH = "c:/home/blowagie/key.properties";
/** Some properties used when signing. */
public static Properties properties = new Properties();
/**
* Creates a PDF that is encrypted using two different public certificates.
* @param filename the path to the resulting PDF file
* @throws IOException
* @throws DocumentException
* @throws GeneralSecurityException
*/
public void createPdf(String filename)
throws IOException, DocumentException, GeneralSecurityException {
// step 1
Document document = new Document();
// step 2
PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(RESULT1));
Certificate cert1 = getPublicCertificate("c:/resources/encryption/foobar.cer");
Certificate cert2 = getPublicCertificate(properties.getProperty("PUBLIC"));
writer.setEncryption(new Certificate[]{cert1, cert2},
new int[]{PdfWriter.ALLOW_PRINTING, PdfWriter.ALLOW_COPY}, PdfWriter.ENCRYPTION_AES_128);
// step 3
document.open();
// step 4
document.add(new Paragraph("Hello World!"));
// step 5
document.close();
}
/**
* Gets a public certificate from a certificate file.
* @param path the path to the certificate
* @return a Certificate object
* @throws IOException
* @throws CertificateException
*/
public Certificate getPublicCertificate(String path)
throws IOException, CertificateException {
FileInputStream is = new FileInputStream(path);
CertificateFactory cf = CertificateFactory.getInstance("X.509");
X509Certificate cert = (X509Certificate) cf.generateCertificate(is);
return cert;
}
/**
* Gets a private key from a KeyStore.
* @return a PrivateKey object
* @throws GeneralSecurityException
* @throws IOException
*/
public PrivateKey getPrivateKey() throws GeneralSecurityException, IOException {
String path = "c:/resources/encryption/.keystore";
KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
ks.load(new FileInputStream(path), "f00b4r".toCharArray());
PrivateKey pk = (PrivateKey)ks.getKey("foobar", "f1lmf3st".toCharArray());
return pk;
}
/**
* Decrypts a PDF that was encrypted using a certificate
* @param src The encrypted PDF
* @param dest The decrypted PDF
* @throws IOException
* @throws DocumentException
* @throws GeneralSecurityException
*/
public void decryptPdf(String src, String dest)
throws IOException, DocumentException, GeneralSecurityException {
PdfReader reader = new PdfReader(src,
getPublicCertificate("c:/resources/encryption/foobar.cer"), getPrivateKey(), "BC");
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
stamper.close();
}
/**
* Encrypts a PDF using a public certificate.
* @param src The original PDF document
* @param dest The encrypted PDF document
* @throws IOException
* @throws DocumentException
* @throws CertificateException
*/
public void encryptPdf(String src, String dest)
throws IOException, DocumentException, CertificateException {
PdfReader reader = new PdfReader(src);
PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(dest));
Certificate cert = getPublicCertificate("c:/resources/encryption/foobar.cer");
stamper.setEncryption(new Certificate[]{cert},
new int[]{PdfWriter.ALLOW_PRINTING}, PdfWriter.ENCRYPTION_AES_128);
stamper.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());
properties.load(new FileInputStream(PATH));
EncryptWithCertificate hello = new EncryptWithCertificate();
hello.createPdf(RESULT1);
hello.decryptPdf(RESULT1, RESULT2);
hello.encryptPdf(RESULT2, RESULT3);
}
}
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