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Java

Duplicate openssl smime -decrypt -in some_file.dat.enc -binary -inform DER -inkey private.key -out some_file.dat

See more OpenSSL Examples

Demonstrates how to decrypt binary DER that was encrypted using the following openssl command:
openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

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.

    // Duplicates the following openssl command:
    // openssl smime -decrypt -in hello.txt.enc -binary -inform DER -inkey private.key -out hello.txt

    CkCert cert = new CkCert();
    success = cert.LoadFromFile("qa_data/openssl/EE.cer");
    if (success == false) {
        System.out.println(cert.lastErrorText());
        return;
        }

    CkBinData bd = new CkBinData();
    success = bd.LoadFile("qa_data/openssl/EE.key");
    // Assuming success..

    CkPrivateKey privKey = new CkPrivateKey();
    success = privKey.LoadAnyFormat(bd,"");
    if (success == false) {
        System.out.println(privKey.lastErrorText());
        return;
        }

    CkCrypt2 crypt = new CkCrypt2();
    success = crypt.SetDecryptCert2(cert,privKey);
    if (success == false) {
        System.out.println(crypt.lastErrorText());
        return;
        }

    crypt.put_CryptAlgorithm("PKI");
    success = crypt.CkDecryptFile("qa_data/openssl/hello.txt.enc","qa_output/hello.txt");
    if (success == false) {
        System.out.println(crypt.lastErrorText());
        return;
        }

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