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Java

Duplicate OpensSSL to Create Signature using Cert and Key Files

See more OpenSSL Examples

This example duplicates the following:
openssl smime –sign -in something.xml -out something.der -signer mycert.crt -inkey cert.key -outform der –nodetach

Note: Although "smime" is the OpenSSL command, it's not actually producing S/MIME. The arguments "-outform der -binary" indicates that the output is binary DER (i.e. the PKCS7 binary signature). The input can be any type of file: XML, PDF, JPG, ... *anything*...

Chilkat Java Downloads

Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2 crypt = new CkCrypt2();

    // Load the cert and private key from separate files.
    CkCert cert = new CkCert();
    success = cert.LoadFromFile("myCert.crt");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

    CkBinData bd = new CkBinData();
    success = bd.LoadFile("cert.key");
    CkPrivateKey privkey = new CkPrivateKey();
    // Load from any format private key.
    // If the file does not need a password, the 2nd arg is ignored.
    success = privkey.LoadAnyFormat(bd,"password_if_needed");
    if (success != true) {
        System.out.println(privkey.lastErrorText());
        return;
        }

    success = crypt.SetSigningCert2(cert,privkey);
    if (success != true) {
        System.out.println(crypt.lastErrorText());
        return;
        }

    // Create the opaque signature (PKCS7 binary DER that contains both the signature and original file data).
    success = crypt.CreateP7M("qa_data/infile.anything","qa_output/outfile.der");
    if (success != true) {
        System.out.println(crypt.lastErrorText());
        return;
        }

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