Digital signatures using itext 5.5.5

Question

I upgraded from iText 5.2.1 to iText 5.5.5

I was using PdfStamper along with PdfSignatureApperance to apply digital signatures.

Here is my snippet of code.

PdfStamper stamper = PdfStamper.createSignature(reader, byteArrayOutputStream,'\0');
PdfSignatureAppearance appearance = stamper.getSignatureAppearance();
appearance.setCrypto(key, chain, null, PdfSignatureAppearance.WINCER_SIGNED);

From the above code, there are couple of things which are not present in the current version.

1) In version 5.5.5 of iText I can't find "setCrypto" method of PdfSignatureApperance class.

2) PdfSignatureApperance doesn't consist of WINCER_SIGNED.

If anyone can help me with applying digital signatures with new alternatives.

Thanks.

In the course of the 5.3.x versions iText signing has been fundamentally improved. You might want to download Digital Signatures for PDF documents, A White Paper by Bruno Lowagie (iText Software) on creating and verifying digital PDF signatures using iText to catch up. — mkl

Orden Orden · Accepted Answer · 2018-11-28T16:17:29

In fact since iText 5.3 the signature API has a bit changed and the setCrypto method is not present anymore. I read the white paper of Bruno and here is the code that is working for me:

PdfReader reader = new PdfReader(new FileInputStream(file));
FileOutputStream fout = new FileOutputStream(new File(targetDir, fileName));
PdfStamper stp = PdfStamper.createSignature(reader, fout, '\0');

PdfSignatureAppearance sap = stp.getSignatureAppearance();
sap.setReason(reason);
sap.setLocation("Pleber-Christ");

ExternalDigest digest = new BouncyCastleDigest();
BouncyCastleProvider provider = new BouncyCastleProvider();
ExternalSignature signature = new PrivateKeySignature(key, DigestAlgorithms.SHA256, provider.getName());
MakeSignature.signDetached(sap, digest, signature, chain,   null, null, null, 0, CryptoStandard.CMS);

You have to put bcprov-jdk15on-1.60.jar and bcpkix-jdk15on-1.60.jar in your classpath. You may have to change it a bit to fit your needs.

Digital signatures using itext 5.5.5

1 Answers