package de.blinkt.openvpn;

import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.Build;
import android.preference.PreferenceManager;
import android.security.KeyChain;
import android.security.KeyChainException;
import android.util.Base64;
import android.widget.Toast;

import de.blinkt.openvpn.core.NativeUtils;
import de.blinkt.openvpn.core.VpnStatus;
import de.blinkt.openvpn.core.OpenVpnService;
import de.blinkt.openvpn.core.X509Utils;
import org.spongycastle.util.io.pem.PemObject;
import org.spongycastle.util.io.pem.PemWriter;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import java.io.*;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.Collection;
import java.util.Locale;
import java.util.UUID;
import java.util.Vector;

public class VpnProfile implements Serializable {
    // Note that this class cannot be moved to core where it belongs since
    // the profile loading depends on it being here
    // The Serializable documentation mentions that class name change are possible
    // but the how is unclear
    //
    transient public static final long MAX_EMBED_FILE_SIZE = 2048*1024; // 2048kB
    // Don't change this, not all parts of the program use this constant
    public static final String EXTRA_PROFILEUUID = "de.blinkt.openvpn.profileUUID";
    public static final String INLINE_TAG = "[[INLINE]]";
    public static final String MINIVPN = "miniopenvpn";
    private static final long serialVersionUID = 7085688938959334563L;
    private static final String OVPNCONFIGFILE = "android.conf";
    public static final int MAXLOGLEVEL = 4;
    public static String DEFAULT_DNS1 = "8.8.8.8";
    public static String DEFAULT_DNS2 = "8.8.4.4";

    public transient String mTransientPW = null;
    public transient String mTransientPCKS12PW = null;


    public static final int TYPE_CERTIFICATES = 0;
    public static final int TYPE_PKCS12 = 1;
    public static final int TYPE_KEYSTORE = 2;
    public static final int TYPE_USERPASS = 3;
    public static final int TYPE_STATICKEYS = 4;
    public static final int TYPE_USERPASS_CERTIFICATES = 5;
    public static final int TYPE_USERPASS_PKCS12 = 6;
    public static final int TYPE_USERPASS_KEYSTORE = 7;
    public static final int X509_VERIFY_TLSREMOTE = 0;
    public static final int X509_VERIFY_TLSREMOTE_COMPAT_NOREMAPPING = 1;
    public static final int X509_VERIFY_TLSREMOTE_DN = 2;
    public static final int X509_VERIFY_TLSREMOTE_RDN = 3;
    public static final int X509_VERIFY_TLSREMOTE_RDN_PREFIX = 4;
    // variable named wrong and should haven beeen transient
    // but needs to keep wrong name to guarante loading of old
    // profiles
    public transient boolean profileDleted = false;
    public int mAuthenticationType = TYPE_KEYSTORE;
    public String mName;
    public String mAlias;
    public String mClientCertFilename;
    public String mTLSAuthDirection = "";
    public String mTLSAuthFilename;
    public String mClientKeyFilename;
    public String mCaFilename;
    public boolean mUseLzo = true;
    public String mServerPort = "1194";
    public boolean mUseUdp = true;
    public String mPKCS12Filename;
    public String mPKCS12Password;
    public boolean mUseTLSAuth = false;
    public String mServerName = "openvpn.blinkt.de";
    public String mDNS1 = DEFAULT_DNS1;
    public String mDNS2 = DEFAULT_DNS2;
    public String mIPv4Address;
    public String mIPv6Address;
    public boolean mOverrideDNS = false;
    public String mSearchDomain = "blinkt.de";
    public boolean mUseDefaultRoute = true;
    public boolean mUsePull = true;
    public String mCustomRoutes;
    public boolean mCheckRemoteCN = false;
    public boolean mExpectTLSCert = true;
    public String mRemoteCN = "";
    public String mPassword = "";
    public String mUsername = "";
    public boolean mRoutenopull = false;
    public boolean mUseRandomHostname = false;
    public boolean mUseFloat = false;
    public boolean mUseCustomConfig = false;
    public String mCustomConfigOptions = "";
    public String mVerb = "1";  //ignored
    public String mCipher = "";
    public boolean mNobind = false;
    public boolean mUseDefaultRoutev6 = true;
    public String mCustomRoutesv6 = "";
    public String mKeyPassword = "";
    public boolean mPersistTun = false;
    public String mConnectRetryMax = "5";
    public String mConnectRetry = "5";
    public boolean mUserEditable = true;
    public String mAuth = "";
    public int mX509AuthType = X509_VERIFY_TLSREMOTE_RDN;
    private transient PrivateKey mPrivateKey;
    // Public attributes, since I got mad with getter/setter
    // set members to default values
    private UUID mUuid;

    public VpnProfile(String name) {
        mUuid = UUID.randomUUID();
        mName = name;
    }

    public static String openVpnEscape(String unescaped) {
        if (unescaped == null)
            return null;
        String escapedString = unescaped.replace("\\", "\\\\");
        escapedString = escapedString.replace("\"", "\\\"");
        escapedString = escapedString.replace("\n", "\\n");

        if (escapedString.equals(unescaped) && !escapedString.contains(" ") && !escapedString.contains("#"))
            return unescaped;
        else
            return '"' + escapedString + '"';
    }

    public void clearDefaults() {
        mServerName = "unknown";
        mUsePull = false;
        mUseLzo = false;
        mUseDefaultRoute = false;
        mUseDefaultRoutev6 = false;
        mExpectTLSCert = false;
        mPersistTun = false;
    }

    public UUID getUUID() {
        return mUuid;

    }

    public String getName() {
        if (mName==null)
            return "No profile name";
        return mName;
    }

    public String getConfigFile(Context context, boolean configForOvpn3) {

        File cacheDir = context.getCacheDir();
        String cfg = "";

        // Enable managment interface
        cfg += "# Enables connection to GUI\n";
        cfg += "management ";

        cfg += cacheDir.getAbsolutePath() + "/" + "mgmtsocket";
        cfg += " unix\n";
        cfg += "management-client\n";
        // Not needed, see updated man page in 2.3
        //cfg += "management-signal\n";
        cfg += "management-query-passwords\n";
        cfg += "management-hold\n\n";
        cfg += getVersionEnvString(context);

        cfg += "machine-readable-output\n";


        boolean useTLSClient = (mAuthenticationType != TYPE_STATICKEYS);

        if (useTLSClient && mUsePull)
            cfg += "client\n";
        else if (mUsePull)
            cfg += "pull\n";
        else if (useTLSClient)
            cfg += "tls-client\n";


        //cfg += "verb " + mVerb + "\n";
        cfg += "verb " + MAXLOGLEVEL + "\n";

        if (mConnectRetryMax == null) {
            mConnectRetryMax = "5";
        }

        if (!mConnectRetryMax.equals("-1"))
            cfg += "connect-retry-max " + mConnectRetryMax + "\n";

        if (mConnectRetry == null)
            mConnectRetry = "5";


        cfg += "connect-retry " + mConnectRetry + "\n";

        cfg += "resolv-retry 60\n";


        // We cannot use anything else than tun
        cfg += "dev tun\n";

        // Server Address
        cfg += "remote ";
        cfg += mServerName;
        cfg += " ";
        cfg += mServerPort;
        if (mUseUdp)
            cfg += " udp\n";
        else
            cfg += " tcp-client\n";


        switch (mAuthenticationType) {
            case VpnProfile.TYPE_USERPASS_CERTIFICATES:
                cfg += "auth-user-pass\n";
            case VpnProfile.TYPE_CERTIFICATES:
                // Ca
                cfg += insertFileData("ca", mCaFilename);

                // Client Cert + Key
                cfg += insertFileData("key", mClientKeyFilename);
                cfg += insertFileData("cert", mClientCertFilename);

                break;
            case VpnProfile.TYPE_USERPASS_PKCS12:
                cfg += "auth-user-pass\n";
            case VpnProfile.TYPE_PKCS12:
                cfg += insertFileData("pkcs12", mPKCS12Filename);
                break;

            case VpnProfile.TYPE_USERPASS_KEYSTORE:
                cfg += "auth-user-pass\n";
            case VpnProfile.TYPE_KEYSTORE:
                if (!configForOvpn3) {
                    String[] ks = getKeyStoreCertificates(context);
                    cfg += "### From Keystore ####\n";
                    if (ks != null) {
                        cfg += "<ca>\n" + ks[0] + "\n</ca>\n";
                        if (ks[1] != null)
                            cfg += "<extra-certs>\n" + ks[1] + "\n</extra-certs>\n";
                        cfg += "<cert>\n" + ks[2] + "\n</cert>\n";
                        cfg += "management-external-key\n";
                    } else {
                        cfg += context.getString(R.string.keychain_access) + "\n";
                        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN)
                            if (!mAlias.matches("^[a-zA-Z0-9]$"))
                                cfg += context.getString(R.string.jelly_keystore_alphanumeric_bug) + "\n";
                    }
                }
                break;
            case VpnProfile.TYPE_USERPASS:
                cfg += "auth-user-pass\n";
                cfg += insertFileData("ca", mCaFilename);
        }

        if (mUseLzo) {
            cfg += "comp-lzo\n";
        }

        if (mUseTLSAuth) {
            if (mAuthenticationType == TYPE_STATICKEYS)
                cfg += insertFileData("secret", mTLSAuthFilename);
            else
                cfg += insertFileData("tls-auth", mTLSAuthFilename);

            if (nonNull(mTLSAuthDirection)) {
                cfg += "key-direction ";
                cfg += mTLSAuthDirection;
                cfg += "\n";
            }

        }

        if (!mUsePull) {
            if (nonNull(mIPv4Address))
                cfg += "ifconfig " + cidrToIPAndNetmask(mIPv4Address) + "\n";

            if (nonNull(mIPv6Address))
                cfg += "ifconfig-ipv6 " + mIPv6Address + "\n";
        }

        if (mUsePull && mRoutenopull)
            cfg += "route-nopull\n";

        String routes = "";
        int numroutes = 0;
        if (mUseDefaultRoute)
            routes += "route 0.0.0.0 0.0.0.0\n";
        else
            for (String route : getCustomRoutes()) {
                routes += "route " + route + "\n";
                numroutes++;
            }


        if (mUseDefaultRoutev6)
            cfg += "route-ipv6 ::/0\n";
        else
            for (String route : getCustomRoutesv6()) {
                routes += "route-ipv6 " + route + "\n";
                numroutes++;
            }

        // Round number to next 100
        if (numroutes > 90) {
            numroutes = ((numroutes / 100) + 1) * 100;
            cfg += "# Alot of routes are set, increase max-routes\n";
            cfg += "max-routes " + numroutes + "\n";
        }
        cfg += routes;

        if (mOverrideDNS || !mUsePull) {
            if (nonNull(mDNS1))
                cfg += "dhcp-option DNS " + mDNS1 + "\n";
            if (nonNull(mDNS2))
                cfg += "dhcp-option DNS " + mDNS2 + "\n";
            if (nonNull(mSearchDomain))
                cfg += "dhcp-option DOMAIN " + mSearchDomain + "\n";

        }

        if (mNobind)
            cfg += "nobind\n";


        // Authentication
        if (mCheckRemoteCN) {
            if (mRemoteCN == null || mRemoteCN.equals(""))
                cfg += "verify-x509-name " + mServerName + " name\n";
            else
                switch (mX509AuthType) {

                    // 2.2 style x509 checks
                    case X509_VERIFY_TLSREMOTE_COMPAT_NOREMAPPING:
                        cfg += "compat-names no-remapping\n";
                    case X509_VERIFY_TLSREMOTE:
                        cfg += "tls-remote " + openVpnEscape(mRemoteCN) + "\n";
                        break;

                    case X509_VERIFY_TLSREMOTE_RDN:
                        cfg += "verify-x509-name " + openVpnEscape(mRemoteCN) + " name\n";
                        break;

                    case X509_VERIFY_TLSREMOTE_RDN_PREFIX:
                        cfg += "verify-x509-name " + openVpnEscape(mRemoteCN) + " name-prefix\n";
                        break;

                    case X509_VERIFY_TLSREMOTE_DN:
                        cfg += "verify-x509-name " + openVpnEscape(mRemoteCN) + "\n";
                        break;
                }
        }
        if (mExpectTLSCert)
            cfg += "remote-cert-tls server\n";


        if (nonNull(mCipher)) {
            cfg += "cipher " + mCipher + "\n";
        }

        if (nonNull(mAuth)) {
            cfg += "auth " + mAuth + "\n";
        }

        // Obscure Settings dialog
        if (mUseRandomHostname)
            cfg += "#my favorite options :)\nremote-random-hostname\n";

        if (mUseFloat)
            cfg += "float\n";

        if (mPersistTun) {
            cfg += "persist-tun\n";
            cfg += "# persist-tun also enables pre resolving to avoid DNS resolve problem\n";
            cfg += "preresolve\n";
        }

        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
        boolean usesystemproxy = prefs.getBoolean("usesystemproxy", true);
        if (usesystemproxy) {
            cfg += "# Use system proxy setting\n";
            cfg += "management-query-proxy\n";
        }


        if (mUseCustomConfig) {
            cfg += "# Custom configuration options\n";
            cfg += "# You are on your on own here :)\n";
            cfg += mCustomConfigOptions;
            cfg += "\n";

        }


        return cfg;
    }

    private String getVersionEnvString(Context c) {
        String version = "unknown";
        try {
            PackageInfo packageinfo = c.getPackageManager().getPackageInfo(c.getPackageName(), 0);
            version = packageinfo.versionName;
        } catch (PackageManager.NameNotFoundException e) {
            VpnStatus.logException(e);
        }
        return String.format(Locale.US, "setenv IV_OPENVPN_GUI_VERSION \"%s %s\"\n", c.getPackageName(), version);

    }

    //! Put inline data inline and other data as normal escaped filename
    private String insertFileData(String cfgentry, String filedata) {
        if (filedata == null) {
            // TODO: generate good error
            return String.format("%s %s\n", cfgentry, "missing");
        } else if (filedata.startsWith(VpnProfile.INLINE_TAG)) {
            String datawoheader = filedata.substring(VpnProfile.INLINE_TAG.length());
            return String.format(Locale.ENGLISH, "<%s>\n%s\n</%s>\n", cfgentry, datawoheader, cfgentry);
        } else {
            return String.format(Locale.ENGLISH, "%s %s\n", cfgentry, openVpnEscape(filedata));
        }
    }

    private boolean nonNull(String val) {
        if (val == null || val.equals(""))
            return false;
        else
            return true;
    }

    private Collection<String> getCustomRoutes() {
        Vector<String> cidrRoutes = new Vector<String>();
        if (mCustomRoutes == null) {
            // No routes set, return empty vector
            return cidrRoutes;
        }
        for (String route : mCustomRoutes.split("[\n \t]")) {
            if (!route.equals("")) {
                String cidrroute = cidrToIPAndNetmask(route);
                if (cidrroute == null)
                    return null;

                cidrRoutes.add(cidrroute);
            }
        }

        return cidrRoutes;
    }

    private Collection<String> getCustomRoutesv6() {
        Vector<String> cidrRoutes = new Vector<String>();
        if (mCustomRoutesv6 == null) {
            // No routes set, return empty vector
            return cidrRoutes;
        }
        for (String route : mCustomRoutesv6.split("[\n \t]")) {
            if (!route.equals("")) {
                cidrRoutes.add(route);
            }
        }

        return cidrRoutes;
    }

    private String cidrToIPAndNetmask(String route) {
        String[] parts = route.split("/");

        // No /xx, assume /32 as netmask
        if (parts.length == 1)
            parts = (route + "/32").split("/");

        if (parts.length != 2)
            return null;
        int len;
        try {
            len = Integer.parseInt(parts[1]);
        } catch (NumberFormatException ne) {
            return null;
        }
        if (len < 0 || len > 32)
            return null;


        long nm = 0xffffffffl;
        nm = (nm << (32 - len)) & 0xffffffffl;

        String netmask = String.format(Locale.ENGLISH, "%d.%d.%d.%d", (nm & 0xff000000) >> 24, (nm & 0xff0000) >> 16, (nm & 0xff00) >> 8, nm & 0xff);
        return parts[0] + "  " + netmask;
    }

    private String[] buildOpenvpnArgv(File cacheDir) {
        Vector<String> args = new Vector<String>();

        // Add fixed paramenters
        //args.add("/data/data/de.blinkt.openvpn/lib/openvpn");
        args.add(cacheDir.getAbsolutePath() + "/" + VpnProfile.MINIVPN);

        args.add("--config");
        args.add(cacheDir.getAbsolutePath() + "/" + OVPNCONFIGFILE);


        return args.toArray(new String[args.size()]);
    }

    public Intent prepareIntent(Context context) {
        String prefix = context.getPackageName();

        Intent intent = new Intent(context, OpenVpnService.class);

        if (mAuthenticationType == VpnProfile.TYPE_KEYSTORE || mAuthenticationType == VpnProfile.TYPE_USERPASS_KEYSTORE) {
            if (getKeyStoreCertificates(context) == null)
                return null;
        }

        intent.putExtra(prefix + ".ARGV", buildOpenvpnArgv(context.getCacheDir()));
        intent.putExtra(prefix + ".profileUUID", mUuid.toString());

        ApplicationInfo info = context.getApplicationInfo();
        intent.putExtra(prefix + ".nativelib", info.nativeLibraryDir);

        try {
            FileWriter cfg = new FileWriter(context.getCacheDir().getAbsolutePath() + "/" + OVPNCONFIGFILE);
            cfg.write(getConfigFile(context, false));
            cfg.flush();
            cfg.close();
        } catch (IOException e) {
            VpnStatus.logException(e);
        }

        return intent;
    }

    String[] getKeyStoreCertificates(Context context) {
        return getKeyStoreCertificates(context, 5);
    }

    class NoCertReturnedException extends Exception {
        public NoCertReturnedException (String msg) {
            super(msg);
        }
    }

    synchronized String[] getKeyStoreCertificates(Context context,int tries) {
        PrivateKey privateKey = null;
        X509Certificate[] cachain;
        Exception exp=null;
        try {
            privateKey = KeyChain.getPrivateKey(context, mAlias);
            mPrivateKey = privateKey;

            String keystoreChain = null;


            cachain = KeyChain.getCertificateChain(context, mAlias);
            if(cachain == null)
                throw new NoCertReturnedException("No certificate returned from Keystore");

            if (cachain.length <= 1 && !nonNull(mCaFilename)) {
                VpnStatus.logMessage(VpnStatus.LogLevel.ERROR, "", context.getString(R.string.keychain_nocacert));
            } else {
                StringWriter ksStringWriter = new StringWriter();

                PemWriter pw = new PemWriter(ksStringWriter);
                for (int i = 1; i < cachain.length; i++) {
                    X509Certificate cert = cachain[i];
                    pw.writeObject(new PemObject("CERTIFICATE", cert.getEncoded()));
                }
                pw.close();
                keystoreChain = ksStringWriter.toString();
            }


            String caout = null;
            if (nonNull(mCaFilename)) {
                try {
                    Certificate cacert = X509Utils.getCertificateFromFile(mCaFilename);
                    StringWriter caoutWriter = new StringWriter();
                    PemWriter pw = new PemWriter(caoutWriter);

                    pw.writeObject(new PemObject("CERTIFICATE", cacert.getEncoded()));
                    pw.close();
                    caout= caoutWriter.toString();

                } catch (Exception e) {
                    VpnStatus.logError("Could not read CA certificate" + e.getLocalizedMessage());
                }
            }


            StringWriter certout = new StringWriter();


            if (cachain.length >= 1) {
                X509Certificate usercert = cachain[0];

                PemWriter upw = new PemWriter(certout);
                upw.writeObject(new PemObject("CERTIFICATE", usercert.getEncoded()));
                upw.close();

            }
            String user = certout.toString();


            String ca, extra;
            if(caout==null) {
                ca =keystoreChain;
                extra=null;
            } else {
                ca = caout;
                extra=keystoreChain;
            }

            return new String[]{ca, extra, user};
        } catch (InterruptedException e) {
            exp=e;
        } catch (FileNotFoundException e) {
            exp=e;
        } catch (CertificateException e) {
            exp=e;
        } catch (IOException e) {
            exp=e;
        } catch (KeyChainException e) {
            exp=e;
        } catch (NoCertReturnedException e) {
            exp =e;
        } catch (IllegalArgumentException e) {
            exp =e;
        } catch (AssertionError e) {
            if (tries ==0)
                return null;
            VpnStatus.logError(String.format("Failure getting Keystore Keys (%s), retrying",e.getLocalizedMessage()));
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e1) {
                VpnStatus.logException(e1);
            }
            return getKeyStoreCertificates(context, tries-1);
        }
        if (exp != null) {
            exp.printStackTrace();
            VpnStatus.logError(R.string.keyChainAccessError, exp.getLocalizedMessage());

            VpnStatus.logError(R.string.keychain_access);
            if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN) {
                if (!mAlias.matches("^[a-zA-Z0-9]$")) {
                    VpnStatus.logError(R.string.jelly_keystore_alphanumeric_bug);
                }
            }
        }
        return null;
    }

    //! Return an error if somethign is wrong
    public int checkProfile(Context context) {
        if (mAuthenticationType == TYPE_KEYSTORE || mAuthenticationType == TYPE_USERPASS_KEYSTORE) {
            if (mAlias == null)
                return R.string.no_keystore_cert_selected;
        }

        if (!mUsePull) {
            if (mIPv4Address == null || cidrToIPAndNetmask(mIPv4Address) == null)
                return R.string.ipv4_format_error;
        }
        if (!mUseDefaultRoute && getCustomRoutes() == null)
            return R.string.custom_route_format_error;

        // Everything okay
        return R.string.no_error_found;

    }

    //! Openvpn asks for a "Private Key", this should be pkcs12 key
    //
    public String getPasswordPrivateKey() {
        if (mTransientPCKS12PW != null) {
            String pwcopy = mTransientPCKS12PW;
            mTransientPCKS12PW = null;
            return pwcopy;
        }
        switch (mAuthenticationType) {
            case TYPE_PKCS12:
            case TYPE_USERPASS_PKCS12:
                return mPKCS12Password;

            case TYPE_CERTIFICATES:
            case TYPE_USERPASS_CERTIFICATES:
                return mKeyPassword;

            case TYPE_USERPASS:
            case TYPE_STATICKEYS:
            default:
                return null;
        }
    }

    boolean isUserPWAuth() {
        switch (mAuthenticationType) {
            case TYPE_USERPASS:
            case TYPE_USERPASS_CERTIFICATES:
            case TYPE_USERPASS_KEYSTORE:
            case TYPE_USERPASS_PKCS12:
                return true;
            default:
                return false;

        }
    }

    public boolean requireTLSKeyPassword() {
        if (!nonNull(mClientKeyFilename))
            return false;

        String data = "";
        if (mClientKeyFilename.startsWith(INLINE_TAG))
            data = mClientKeyFilename;
        else {
            char[] buf = new char[2048];
            FileReader fr;
            try {
                fr = new FileReader(mClientKeyFilename);
                int len = fr.read(buf);
                while (len > 0) {
                    data += new String(buf, 0, len);
                    len = fr.read(buf);
                }
                fr.close();
            } catch (FileNotFoundException e) {
                return false;
            } catch (IOException e) {
                return false;
            }

        }

        if (data.contains("Proc-Type: 4,ENCRYPTED"))
            return true;
        else if (data.contains("-----BEGIN ENCRYPTED PRIVATE KEY-----"))
            return true;
        else
            return false;
    }

    public int needUserPWInput() {
        if ((mAuthenticationType == TYPE_PKCS12 || mAuthenticationType == TYPE_USERPASS_PKCS12) &&
                (mPKCS12Password == null || mPKCS12Password.equals(""))) {
            if (mTransientPCKS12PW == null)
                return R.string.pkcs12_file_encryption_key;
        }

        if (mAuthenticationType == TYPE_CERTIFICATES || mAuthenticationType == TYPE_USERPASS_CERTIFICATES) {
            if (requireTLSKeyPassword() && !nonNull(mKeyPassword))
                if (mTransientPCKS12PW == null) {
                    return R.string.private_key_password;
                }
        }

        if (isUserPWAuth() && !(nonNull(mUsername) && (nonNull(mPassword) || mTransientPW != null))) {
            return R.string.password;
        }
        return 0;
    }

    public String getPasswordAuth() {
        if (mTransientPW != null) {
            String pwcopy = mTransientPW;
            mTransientPW = null;
            return pwcopy;
        } else {
            return mPassword;
        }
    }

    // Used by the Array Adapter
    @Override
    public String toString() {
        return mName;
    }

    public String getUUIDString() {
        return mUuid.toString();
    }

    public PrivateKey getKeystoreKey() {
        return mPrivateKey;
    }

    public String getSignedData(String b64data) {
        PrivateKey privkey = getKeystoreKey();
        Exception err;

        byte[] data = Base64.decode(b64data, Base64.DEFAULT);

        // The Jelly Bean *evil* Hack
        // 4.2 implements the RSA/ECB/PKCS1PADDING in the OpenSSLprovider
        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN) {
            return processSignJellyBeans(privkey, data);
        }


        try {


            Cipher rsasinger = Cipher.getInstance("RSA/ECB/PKCS1PADDING");

            rsasinger.init(Cipher.ENCRYPT_MODE, privkey);

            byte[] signed_bytes = rsasinger.doFinal(data);
            return Base64.encodeToString(signed_bytes, Base64.NO_WRAP);

        } catch (NoSuchAlgorithmException e) {
            err = e;
        } catch (InvalidKeyException e) {
            err = e;
        } catch (NoSuchPaddingException e) {
            err = e;
        } catch (IllegalBlockSizeException e) {
            err = e;
        } catch (BadPaddingException e) {
            err = e;
        }

        VpnStatus.logError(R.string.error_rsa_sign, err.getClass().toString(), err.getLocalizedMessage());

        return null;

    }

    private String processSignJellyBeans(PrivateKey privkey, byte[] data) {
        Exception err;
        try {
            Method getKey = privkey.getClass().getSuperclass().getDeclaredMethod("getOpenSSLKey");
            getKey.setAccessible(true);

            // Real object type is OpenSSLKey
            Object opensslkey = getKey.invoke(privkey);

            getKey.setAccessible(false);

            Method getPkeyContext = opensslkey.getClass().getDeclaredMethod("getPkeyContext");

            // integer pointer to EVP_pkey
            getPkeyContext.setAccessible(true);
            int pkey = (Integer) getPkeyContext.invoke(opensslkey);
            getPkeyContext.setAccessible(false);

            // 112 with TLS 1.2 (172 back with 4.3), 36 with TLS 1.0
            byte[] signed_bytes = NativeUtils.rsasign(data, pkey);
            return Base64.encodeToString(signed_bytes, Base64.NO_WRAP);

        } catch (NoSuchMethodException e) {
            err = e;
        } catch (IllegalArgumentException e) {
            err = e;
        } catch (IllegalAccessException e) {
            err = e;
        } catch (InvocationTargetException e) {
            err = e;
        } catch (InvalidKeyException e) {
            err = e;
        }
        VpnStatus.logError(R.string.error_rsa_sign, err.getClass().toString(), err.getLocalizedMessage());

        return null;

    }


}