Java equivalent of an OpenSSL AES CBC encryption

This question has an accepted answer which is a bit old, however this seems to be something that comes up again and again. I have 2 projects were we communicate with 3rd parties and the cipher is OpenSSL AES with a pre-shared key.

I have used the not-yet-common-ssl library. However it appears to be stuck at version 0.3.x and with no releases in almost 2 years, not any mailing list traffic or visible development I have to conclude that this is essentially dead.

Based on some additional stackoverflow questions I did find both Spring Security and Encryptor4j both of which seem to offer some reasonably packaged text encoding. However attempting to get Spring Security’s Encryptors to work at decoding a known encoded text string failed for me, I am guessing that the IV and Key generation used by OpenSSL are simply not supported in the supplied implementation.

By examining the code above, as well as a known working C# and PHP implementation, I was able to come up with a utility class that is currently passing my tests for interoperability. Generally I’d greatly prefer to use a known library, but if there is one I have been unable to locate it. The class (https://gist.github.com/rrsIPOV/4d0f6be7c58173c16e9edf9f97c7d7f2) is as follows:

import groovy.transform.CompileStatic;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.MessageDigest;
import java.security.SecureRandom;
import static java.nio.charset.StandardCharsets.*

/**
* Mimics the OpenSSL AES Cipher options for encrypting and decrypting messages using a shared key (aka password) with symetric ciphers.
*/
@CompileStatic
class OpenSslAes {

/** OpenSSL's magic initial bytes. */
private static final String SALTED_STR = "Salted__";
private static final byte[] SALTED_MAGIC = SALTED_STR.getBytes(US_ASCII);


static String encryptAndURLEncode(String password, String clearText) {
    String encrypted = encrypt(password, clearText);
    return URLEncoder.encode(encrypted, UTF_8.name() );
}

/**
 *
 * @param password  The password / key to encrypt with.
 * @param data      The data to encrypt
 * @return  A base64 encoded string containing the encrypted data.
 */
static String encrypt(String password, String clearText) {
    final byte[] pass = password.getBytes(US_ASCII);
    final byte[] salt = (new SecureRandom()).generateSeed(8);
    final byte[] inBytes = clearText.getBytes(UTF_8);

    final byte[] passAndSalt = array_concat(pass, salt);
    byte[] hash = new byte[0];
    byte[] keyAndIv = new byte[0];
    for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
        final byte[] hashData = array_concat(hash, passAndSalt);
        final MessageDigest md = MessageDigest.getInstance("MD5");
        hash = md.digest(hashData);
        keyAndIv = array_concat(keyAndIv, hash);
    }

    final byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
    final byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
    final SecretKeySpec key = new SecretKeySpec(keyValue, "AES");

    final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
    cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(iv));
    byte[] data = cipher.doFinal(inBytes);
    data =  array_concat(array_concat(SALTED_MAGIC, salt), data);
    return Base64.getEncoder().encodeToString( data );
}

/**
 * @see http://stackoverflow.com/questions/32508961/java-equivalent-of-an-openssl-aes-cbc-encryption  for what looks like a useful answer.  The not-yet-commons-ssl also has an implementation
 * @param password
 * @param source The encrypted data
 * @return
 */
static String decrypt(String password, String source) {
    final byte[] pass = password.getBytes(US_ASCII);

    final byte[] inBytes = Base64.getDecoder().decode(source);

    final byte[] shouldBeMagic = Arrays.copyOfRange(inBytes, 0, SALTED_MAGIC.length);
    if (!Arrays.equals(shouldBeMagic, SALTED_MAGIC)) {
        throw new IllegalArgumentException("Initial bytes from input do not match OpenSSL SALTED_MAGIC salt value.");
    }

    final byte[] salt = Arrays.copyOfRange(inBytes, SALTED_MAGIC.length, SALTED_MAGIC.length + 8);

    final byte[] passAndSalt = array_concat(pass, salt);

    byte[] hash = new byte[0];
    byte[] keyAndIv = new byte[0];
    for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
        final byte[] hashData = array_concat(hash, passAndSalt);
        final MessageDigest md = MessageDigest.getInstance("MD5");
        hash = md.digest(hashData);
        keyAndIv = array_concat(keyAndIv, hash);
    }

    final byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
    final SecretKeySpec key = new SecretKeySpec(keyValue, "AES");

    final byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);

    final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
    cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
    final byte[] clear = cipher.doFinal(inBytes, 16, inBytes.length - 16);
    return new String(clear, UTF_8);
}


private static byte[] array_concat(final byte[] a, final byte[] b) {
    final byte[] c = new byte[a.length + b.length];
    System.arraycopy(a, 0, c, 0, a.length);
    System.arraycopy(b, 0, c, a.length, b.length);
    return c;
}
}