Java

Create CMS Signed File (PDF) with Multiple Signing Certificates

See more Digital Signatures Examples

Demonstrates how to sign a file by adding multiple signatures (multiple certificates). This example signs a PDF file to produce an output file that is a CMS signature wrapping the original PDF. (Note: This is different than modifying a PDF by injecting a signature into the PDF file format.)

Note: This example requires Chilkat v9.5.0.83 or greater.

Chilkat2 Java

import com.chilkatsoft.chilkat2.Cert;
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Crypt2;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example assumes the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        Crypt2 crypt = new Crypt2();

        // ------------ This example requires Chilkat v9.5.0.83 or greater.

        Cert cert1 = new Cert();
        try {
            cert1.loadPfxFile("qa_data/pfx/cert_test123.pfx", "test123");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        Cert cert2 = new Cert();
        try {
            cert2.loadPfxFile("qa_data/pfx/test_secret.pfx", "secret");

            // ------------ This example requires Chilkat v9.5.0.83 or greater.

            // Tell the crypt component to use both certificates for signing.
            // When we create the signature, it will be signed by both certificates.
            crypt.addSigningCert(cert1);

            crypt.addSigningCert(cert2);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // The CadesEnabled property applies to all methods that create PKCS7 signatures.
        // To create a CAdES-BES signature, set this property equal to true.
        crypt.setCadesEnabled(true);

        crypt.setHashAlgorithm("sha256");

        // We can sign any type of file, creating a .p7s as output.
        // The .p7s contains the signature and also embeds the data of the file that is signed.
        String inFile = "qa_data/pdf/sample.pdf";
        String p7sFile = "qa_output/sample.pdf.p7s";

        // Create the CAdES-BES attached signature, which contains the original data.
        // Note: Chilkat's function naming is not accurate.  CreateP7M creates a PKCS7 signature where the signed file
        // is contained within the signature.  CreateP7S creates a detached PKCS7 signature where the signed file
        // is NOT contained within the signature.  We want the data to be contained in the signature, therefore
        // we call CreateP7M even though we are naming our output file .p7s.
        try {
            crypt.createP7M(inFile, p7sFile);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Verify the .p7s file and extract the original file from the .p7s.
        String extractedToFilePath = "qa_output/sample.pdf";
        try {
            crypt.verifyP7M(p7sFile, extractedToFilePath);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Success!");
    }
}