CryptNote is an encryption app for Windows, Android and Linux alleged by Turkey to be used by "FETÖ" - http://www.aksam.com.tr/guncel/fetonun-yeni-haberlesme-agi-cryptnote-desifre-edildi/haber-639566

cryptnote.py

"""
Cryptnote encryption algorithim
"""
import hashlib
import base64
from binascii import unhexlify

from Crypto.Cipher import AES

"""
public OpensslAes128PasswordEncrypter(String password, String charset) throws NoSuchAlgorithmException, NoSuchPaddingException {
    this.charset = charset;
    byte[] iv = makeIvFromPassword(password);
    byte[] key = makeKeyFromPassword(password);
    this.paramSpec = new IvParameterSpec(iv);
    this.keySpec = new SecretKeySpec(key, "AES");
    this.cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
}

private byte[] makeKeyFromPassword(String password) throws NoSuchAlgorithmException {
    String sha = StringUtil.encode("SHA", password).substring(0, 16);
    String keyString = "";
    for (int i = 0; i < 16; i++) {
        keyString = keyString + "0" + sha.substring(i, i + 1);
    }
    return StringUtil.hexStringToByteArray(keyString);
}

private byte[] makeIvFromPassword(String password) throws NoSuchAlgorithmException {
    String md5 = StringUtil.encode("MD5", password).substring(0, 16);
    String ivString = "";
    for (int i = 0; i < 16; i++) {
        ivString = ivString + "0" + md5.substring(i, i + 1);
    }
    return StringUtil.hexStringToByteArray(ivString);
}

public static String encode(String messageDigest, String string)
    throws NoSuchAlgorithmException {
        byte[] plainText = string.getBytes();
        MessageDigest md = MessageDigest.getInstance(messageDigest);
        md.reset();
        md.update(plainText);
        byte[] encodedPassword = md.digest();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < encodedPassword.length; i++) {
            if ((encodedPassword[i] & 0xFF) < 16) {
                sb.append("0");
            }
            sb.append(Long.toString(encodedPassword[i] & 0xFF, 16));
        }
        return sb.toString();
    }
}
"""

def pkcs5_pad(s):
    return s + (16 - len(s) % 16) * chr(16 - len(s) % 16)

def pkcs5_unpad(s):
    return s[0:-ord(s[-1])]


def makeKey(digest, password):
    # Cryptnote only uses 16 hex digests, 64 bit key!!!
    # Every four bits padded with 0000 to make a "128 bit"
    # key from 64 bits of key material.
    sha_hex = stringEncode(digest, password)[0:16]
    keystring = [("0" + byte) for byte in sha_hex]
    return unhexlify("".join(keystring))

def makeKeyFromPassword(password):
    return makeKey("sha1", password)

def makeIVFromPassword(password):
    return makeKey("md5", password)


def stringEncode(messageDigest, plainText):
    md = hashlib.new(messageDigest)
    md.update(plainText.encode("utf-8"))
    return md.hexdigest()

def get_cipher(password):
    key = makeKeyFromPassword(password)
    iv = makeIVFromPassword(password)
    return AES.new(key, AES.MODE_CBC, iv)

def encrypt(password, message):
    cipher = get_cipher(password)
    encrypted = base64.encodestring(cipher.encrypt(pkcs5_pad(data)))
    return "\n".join(["---- BEGIN CRYPTNOTE CONTENT ----",
                      encrypted.rstrip("\n"),
                      "---- END CRYPTNOTE CONTENT ----"])

def decrypt(password, message):
    data = base64.b64decode("".join(message.splitlines()[1:-1]))
    cipher = get_cipher(password)
    return pkcs5_unpad(cipher.decrypt(data))


if __name__ == "__main__":
    password = "password"
    encrypted = """---- BEGIN CRYPTNOTE CONTENT ----
    oZQa5Qe/ndieWsj1k8l81d1jRy0REL63rbup1Hb5b4E=
    ---- END CRYPTNOTE CONTENT ----"""

    print(decrypt(password, encrypted))

    data = " A new message"
    print(encrypt(password, data))