(Android™) openssl enc decrypt

Demonstrates how to decrypt a file that was encrypted using "openssl enc".

This example shows how to decrypt what was created using this openssl command:

openssl enc -e -aes-256-cbc -in hamlet.xml -out hamlet.enc -pass file:./secret.txt

This example shows how to do this:

openssl enc -d -aes-256-cbc -in hamlet.enc -out hamlet_dec.xml -pass file:./secret.txt

Note: This example requires Chilkat v9.5.0.71 or later.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

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

    CkCrypt2 crypt = new CkCrypt2();

    // Use aes-256-cbc
    crypt.put_CryptAlgorithm("aes");
    crypt.put_CipherMode("cbc");
    crypt.put_KeyLength(256);

    // We'll need to set the hash algorithm to either MD5 or SHA256.
    // openssl version 1.0.* or earlier used MD5 by default
    // openssl version 1.1.* uses SHA-256 for the password to secret key derivation.

    // For example, if openssl 1.1.0 was used, we should do this:
    crypt.put_HashAlgorithm("sha256");

    // This example assumes openssl 1.0.2 was used to encrypt what we're now decrypting:
    crypt.put_HashAlgorithm("md5");

    // The openssl command we are duplicating is:
    // 
    //    openssl enc -d -aes-256-cbc -in hamlet.enc -out hamlet_dec.xml -pass file:./secret.txt
    // 
    // The file secret.txt contains the word "secret".  We could write code to load the contents
    // of secret.txt, but instead we'll just do this:
    crypt.SetSecretKeyViaPassword("secret");

    // Load the file to be decrypted.
    CkBinData fileData = new CkBinData();
    boolean success = fileData.LoadFile("qa_data/openssl_enc/hamlet.enc");

    // Decrypt
    success = crypt.DecryptBd(fileData);

    // Save the decrypted output.
    success = fileData.WriteFile("qa_output/hamlet_dec.xml");

    Log.i(TAG, "success = " + String.valueOf(success));

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}