Example usage for java.security KeyStore aliases

List of usage examples for java.security KeyStore aliases

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Introduction

In this page you can find the example usage for java.security KeyStore aliases.

Prototype

public final Enumeration<String> aliases() throws KeyStoreException

Source Link

Document

Lists all the alias names of this keystore.

Usage

From source file:org.adempierelbr.model.MLBRDigitalCertificate.java

/**
 * setCertificate//from  w ww.j av a  2 s.c o  m
 * Set all System.property for webservice connection
 */
public static void setCertificate(Properties ctx, MOrgInfo oi) throws Exception {

    Integer certOrg = (Integer) oi.get_Value("LBR_DC_Org_ID");
    Integer certWS = (Integer) oi.get_Value("LBR_DC_WS_ID");
    MLBRDigitalCertificate dcOrg = new MLBRDigitalCertificate(Env.getCtx(), certOrg, null);
    MLBRDigitalCertificate dcWS = new MLBRDigitalCertificate(Env.getCtx(), certWS, null);

    String orgPassword = dcOrg.getPassword();
    String certType = null;
    InputStream certFileOrg = null;

    if (MLBRDigitalCertificate.LBR_CERTTYPE_PKCS12.equals(dcOrg.getlbr_CertType())) {
        certType = "PKCS12";
        certFileOrg = dcOrg.getAttachment(true).getEntry(0).getInputStream();
        if (certFileOrg == null)
            throw new Exception("Unable to find private key attachment");
    } else if (MLBRDigitalCertificate.LBR_CERTTYPE_PKCS11.equals(dcOrg.getlbr_CertType())) {
        certType = "PKCS11";
        Provider p = new sun.security.pkcs11.SunPKCS11(dcOrg.getConfigurationFile());
        Security.addProvider(p);
    } else
        return; //   Unknown Certificate

    KeyStore ks = KeyStore.getInstance(certType);
    try {
        ks.load(certFileOrg, orgPassword.toCharArray());
    } catch (IOException e) {
        throw new Exception("Incorrect Certificate Password");
    }

    InputStream certFileWS = dcWS.getAttachment(true).getEntry(0).getInputStream();
    if (certFileWS == null) {
        throw new Exception("Unable to find webservices keystore attachment");
    }

    String alias = dcOrg.getAlias();
    if (alias != null && ks.containsAlias(alias) && ks.isKeyEntry(alias))
        ;//   Do Nothing
    else {
        Enumeration<String> aliasesEnum = ks.aliases();
        while (aliasesEnum.hasMoreElements()) {
            alias = (String) aliasesEnum.nextElement();
            if (ks.isKeyEntry(alias))
                break;
        }
    }

    //Erro NFe 3.10
    System.setProperty("sun.security.ssl.allowUnsafeRenegotiation", "true");

    X509Certificate certificate = (X509Certificate) ks.getCertificate(alias);
    PrivateKey privateKey = (PrivateKey) ks.getKey(alias, orgPassword.toCharArray());
    SocketFactoryDinamico socketFactoryDinamico = new SocketFactoryDinamico(certificate, privateKey);
    socketFactoryDinamico.setFileCacerts(certFileWS, dcWS.getPassword());

    Protocol protocol = new Protocol("https", socketFactoryDinamico, 443);
    Protocol.registerProtocol("https", protocol);
}

From source file:org.kse.crypto.x509.X509CertUtil.java

/**
 * Check whether or not a trusted certificate in the supplied KeyStore
 * matches the supplied X.509 certificate.
 *
 * @param cert/*from w w  w .j a  v a 2s.co  m*/
 *            The certificate
 * @param keyStore
 *            The KeyStore
 * @return The alias of the matching certificate in the KeyStore or null if
 *         there is no match
 * @throws CryptoException
 *             If there is a problem establishing trust
 */
public static String matchCertificate(KeyStore keyStore, X509Certificate cert) throws CryptoException {
    try {
        for (Enumeration<String> aliases = keyStore.aliases(); aliases.hasMoreElements();) {
            String alias = aliases.nextElement();
            if (keyStore.isCertificateEntry(alias)) {
                X509Certificate compCert = X509CertUtil.convertCertificate(keyStore.getCertificate(alias));

                if (cert.equals(compCert)) {
                    return alias;
                }
            }
        }
        return null;
    } catch (KeyStoreException ex) {
        throw new CryptoException(res.getString("NoMatchCertificate.exception.message"), ex);
    }
}

From source file:Main.java

public static boolean isCACertificateInstalled(File fileCA, String type, char[] password)
        throws KeyStoreException {

    KeyStore keyStoreCA = null;
    try {/*from   w  w  w. j  a va 2s .  c  o  m*/
        keyStoreCA = KeyStore.getInstance(type/*, "BC"*/);
    } catch (Exception e) {
        e.printStackTrace();
    }

    if (fileCA.exists() && fileCA.canRead()) {
        try {
            FileInputStream fileCert = new FileInputStream(fileCA);
            keyStoreCA.load(fileCert, password);
            fileCert.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (java.security.cert.CertificateException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        Enumeration ex = keyStoreCA.aliases();
        Date exportFilename = null;
        String caAliasValue = "";

        while (ex.hasMoreElements()) {
            String is = (String) ex.nextElement();
            Date lastStoredDate = keyStoreCA.getCreationDate(is);
            if (exportFilename == null || lastStoredDate.after(exportFilename)) {
                exportFilename = lastStoredDate;
                caAliasValue = is;
            }
        }

        try {
            return keyStoreCA.getKey(caAliasValue, password) != null;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (UnrecoverableKeyException e) {
            e.printStackTrace();
        }
    }
    return false;
}

From source file:com.indivica.olis.Driver.java

public static String signData(String data) {
    X509Certificate cert = null;/*from  www .j a v a 2 s.  c  om*/
    PrivateKey priv = null;
    KeyStore keystore = null;
    String pwd = "Olis2011";
    String result = null;
    try {
        Security.addProvider(new BouncyCastleProvider());

        keystore = KeyStore.getInstance("PKCS12", "SunJSSE");
        // Load the keystore
        keystore.load(new FileInputStream(OscarProperties.getInstance().getProperty("olis_keystore")),
                pwd.toCharArray());

        Enumeration e = keystore.aliases();
        String name = "";

        if (e != null) {
            while (e.hasMoreElements()) {
                String n = (String) e.nextElement();
                if (keystore.isKeyEntry(n)) {
                    name = n;
                }
            }
        }

        // Get the private key and the certificate
        priv = (PrivateKey) keystore.getKey(name, pwd.toCharArray());
        cert = (X509Certificate) keystore.getCertificate(name);

        // I'm not sure if this is necessary

        ArrayList<Certificate> certList = new ArrayList<Certificate>();
        certList.add(cert);

        Store certs = new JcaCertStore(certList);

        // Encrypt data
        CMSSignedDataGenerator sgen = new CMSSignedDataGenerator();

        // What digest algorithm i must use? SHA1? MD5? RSA?...
        ContentSigner sha1Signer = new JcaContentSignerBuilder("SHA1withRSA").setProvider("BC").build(priv);
        sgen.addSignerInfoGenerator(new JcaSignerInfoGeneratorBuilder(
                new JcaDigestCalculatorProviderBuilder().setProvider("BC").build()).build(sha1Signer, cert));

        // I'm not sure this is necessary
        sgen.addCertificates(certs);

        // I think that the 2nd parameter need to be false (detached form)
        CMSSignedData csd = sgen.generate(new CMSProcessableByteArray(data.getBytes()), true);

        byte[] signedData = csd.getEncoded();
        byte[] signedDataB64 = Base64.encode(signedData);

        result = new String(signedDataB64);

    } catch (Exception e) {
        MiscUtils.getLogger().error("Can't sign HL7 message for OLIS", e);
    }
    return result;
}

From source file:nu.yona.app.utils.AppUtils.java

public static boolean checkCACertificate() {
    boolean isCertExist = false;
    try {//w w  w.j  a  v  a 2 s .  com
        KeyStore ks = KeyStore.getInstance("AndroidCAStore");
        if (ks != null) {
            ks.load(null, null);
            Enumeration aliases = ks.aliases();
            if (YonaApplication.getEventChangeManager().getDataState().getUser() != null && YonaApplication
                    .getEventChangeManager().getDataState().getUser().getSslRootCertCN() != null) {
                String caCertName = YonaApplication.getEventChangeManager().getDataState().getUser()
                        .getSslRootCertCN();
                if (!TextUtils.isEmpty(caCertName)) {
                    while (aliases.hasMoreElements()) {
                        String alias = (String) aliases.nextElement();
                        java.security.cert.X509Certificate cert = (java.security.cert.X509Certificate) ks
                                .getCertificate(alias);
                        if (cert.getIssuerDN().getName().contains(caCertName)) {
                            isCertExist = true;
                            break;
                        }
                    }
                }
            }
        }
    } catch (Exception e) {
        reportException(AppUtils.class.getSimpleName(), e, Thread.currentThread());
    }
    return isCertExist;

}

From source file:net.sf.keystore_explorer.crypto.x509.X509CertUtil.java

/**
 * Check whether or not a trusted certificate in the supplied KeyStore
 * matches the supplied X.509 certificate.
 *
 * @param cert//from   w w  w.jav a 2 s  . c o m
 *            The certificate
 * @param keyStore
 *            The KeyStore
 * @return The alias of the matching certificate in the KeyStore or null if
 *         there is no match
 * @throws CryptoException
 *             If there is a problem establishing trust
 */
public static String matchCertificate(KeyStore keyStore, X509Certificate cert) throws CryptoException {
    try {
        for (Enumeration aliases = keyStore.aliases(); aliases.hasMoreElements();) {
            String alias = (String) aliases.nextElement();
            if (keyStore.isCertificateEntry(alias)) {
                X509Certificate compCert = X509CertUtil.convertCertificate(keyStore.getCertificate(alias));

                if (cert.equals(compCert)) {
                    return alias;
                }
            }
        }
        return null;
    } catch (KeyStoreException ex) {
        throw new CryptoException(res.getString("NoMatchCertificate.exception.message"), ex);
    }
}

From source file:org.kse.crypto.x509.X509CertUtil.java

private static List<X509Certificate> extractCertificates(KeyStore keyStore) throws CryptoException {
    try {//  w w  w .  ja  v a2  s  .co  m
        List<X509Certificate> certs = new ArrayList<X509Certificate>();

        for (Enumeration<String> aliases = keyStore.aliases(); aliases.hasMoreElements();) {
            String alias = aliases.nextElement();

            if (keyStore.isCertificateEntry(alias)) {
                certs.add(X509CertUtil.convertCertificate(keyStore.getCertificate(alias)));
            }
        }

        return certs;
    } catch (KeyStoreException ex) {
        throw new CryptoException(res.getString("NoExtractCertificates.exception.message"), ex);
    }
}

From source file:org.apache.taverna.security.credentialmanager.impl.CredentialManagerImplIT.java

/**
 * @throws java.lang.Exception//from w  w  w.j a  v a  2 s  . co m
 */
@BeforeClass
@Ignore
public static void setUpBeforeCLass() throws Exception {

    Security.addProvider(new BouncyCastleProvider());

    // Create some test username and passwords for services
    serviceURI = new URI("http://someservice");
    usernamePassword = new UsernamePassword("testuser", "testpasswd");
    serviceURI2 = new URI("http://someservice2");
    usernamePassword2 = new UsernamePassword("testuser2", "testpasswd2");
    serviceURI3 = new URI("http://someservice3");
    usernamePassword3 = new UsernamePassword("testuser3", "testpasswd3");

    // Load the test private key and its certificate
    File privateKeyCertFile = new File(privateKeyFileURL.getPath());
    KeyStore pkcs12Keystore = java.security.KeyStore.getInstance("PKCS12", "BC"); // We have to use the BC provider here as the certificate chain is not loaded if we use whichever provider is first in Java!!!
    FileInputStream inStream = new FileInputStream(privateKeyCertFile);
    pkcs12Keystore.load(inStream, privateKeyAndPKCS12KeystorePassword.toCharArray());
    // KeyStore pkcs12Keystore = credentialManager.loadPKCS12Keystore(privateKeyCertFile, privateKeyPassword);
    Enumeration<String> aliases = pkcs12Keystore.aliases();
    while (aliases.hasMoreElements()) {
        // The test-private-key-cert.p12 file contains only one private key
        // and corresponding certificate entry
        String alias = aliases.nextElement();
        if (pkcs12Keystore.isKeyEntry(alias)) { // is it a (private) key entry?
            privateKey = pkcs12Keystore.getKey(alias, privateKeyAndPKCS12KeystorePassword.toCharArray());
            privateKeyCertChain = pkcs12Keystore.getCertificateChain(alias);
            break;
        }
    }
    inStream.close();

    // Load the test trusted certificate (belonging to *.Google.com)
    File trustedCertFile = new File(trustedCertficateGoogleFileURL.getPath());
    inStream = new FileInputStream(trustedCertFile);
    CertificateFactory certFactory = CertificateFactory.getInstance("X.509");
    trustedCertficateGoogle = (X509Certificate) certFactory.generateCertificate(inStream);
    try {
        inStream.close();
    } catch (Exception e) {
        // Ignore
    }
    // Load the test trusted certificate (belonging to heater.cs.man.ac.uk)
    File trustedCertFile2 = new File(trustedCertficateHeaterFileURL.getPath());
    inStream = new FileInputStream(trustedCertFile2);
    trustedCertficateHeater = (X509Certificate) certFactory.generateCertificate(inStream);
    try {
        inStream.close();
    } catch (Exception e) {
        // Ignore
    }

    credentialManager = new CredentialManagerImpl();

    //      // The code below sets up the Keystore and Truststore files and loads some data into them
    //      // and saves them into a temp directory. These files can later be used for testing the Credential
    //      // Manager with non-empty keystores.
    //      Random randomGenerator = new Random();
    //      String credentialManagerDirectoryPath = System
    //            .getProperty("java.io.tmpdir")
    //            + System.getProperty("file.separator")
    //            + "taverna-security-"
    //            + randomGenerator.nextInt(1000000);
    //      System.out.println("Credential Manager's directory path: "
    //            + credentialManagerDirectoryPath);
    //      credentialManagerDirectory = new File(credentialManagerDirectoryPath);
    //      credentialManager.setConfigurationDirectoryPath(credentialManagerDirectory);
    //      
    //      // Create the dummy master password provider
    //      masterPasswordProvider = new DummyMasterPasswordProvider();
    //      masterPasswordProvider.setMasterPassword(masterPassword);
    //      List<MasterPasswordProvider> masterPasswordProviders = new ArrayList<MasterPasswordProvider>();
    //      masterPasswordProviders.add(masterPasswordProvider);
    //      credentialManager.setMasterPasswordProviders(masterPasswordProviders);
    //      
    //      // Add some stuff into Credential Manager
    //      credentialManager.addUsernameAndPasswordForService(usernamePassword, serviceURI);
    //      credentialManager.addUsernameAndPasswordForService(usernamePassword2, serviceURI2);
    //      credentialManager.addUsernameAndPasswordForService(usernamePassword3, serviceURI3);
    //      credentialManager.addKeyPair(privateKey, privateKeyCertChain);
    //      credentialManager.addTrustedCertificate(trustedCertficate);

    // Set up a random temp directory and copy the test keystore files 
    // from resources/security
    Random randomGenerator = new Random();
    String credentialManagerDirectoryPath = System.getProperty("java.io.tmpdir")
            + System.getProperty("file.separator") + "taverna-security-" + randomGenerator.nextInt(1000000);
    System.out.println("Credential Manager's directory path: " + credentialManagerDirectoryPath);
    credentialManagerDirectory = new File(credentialManagerDirectoryPath);
    if (!credentialManagerDirectory.exists()) {
        credentialManagerDirectory.mkdir();
    }
    URL keystoreFileURL = CredentialManagerImplIT.class.getResource("/security/t2keystore.ubr");
    File keystoreFile = new File(keystoreFileURL.getPath());
    File keystoreDestFile = new File(credentialManagerDirectory, "taverna-keystore.ubr");
    URL truststroreFileURL = CredentialManagerImplIT.class.getResource("/security/t2truststore.ubr");
    File truststoreFile = new File(truststroreFileURL.getPath());
    File truststoreDestFile = new File(credentialManagerDirectory, "taverna-truststore.ubr");
    FileUtils.copyFile(keystoreFile, keystoreDestFile);
    FileUtils.copyFile(truststoreFile, truststoreDestFile);
    credentialManager.setConfigurationDirectoryPath(credentialManagerDirectory.toPath());

    // Create the dummy master password provider
    masterPasswordProvider = new DummyMasterPasswordProvider();
    masterPasswordProvider.setMasterPassword(masterPassword);
    List<MasterPasswordProvider> masterPasswordProviders = new ArrayList<MasterPasswordProvider>();
    masterPasswordProviders.add(masterPasswordProvider);
    credentialManager.setMasterPasswordProviders(masterPasswordProviders);

    // Set an empty list for trust confirmation providers
    credentialManager.setTrustConfirmationProviders(new ArrayList<TrustConfirmationProvider>());

    keystoreChangedObserver = new Observer<KeystoreChangedEvent>() {
        @Override
        public void notify(Observable<KeystoreChangedEvent> sender, KeystoreChangedEvent message)
                throws Exception {
            // TODO Auto-generated method stub
        }
    };
    credentialManager.addObserver(keystoreChangedObserver);
}

From source file:net.sf.taverna.t2.security.credentialmanager.impl.CredentialManagerImplIT.java

/**
 * @throws java.lang.Exception//ww w.ja v a 2  s  . c  o  m
 */
@BeforeClass
@Ignore
public static void setUpBeforeCLass() throws Exception {

    Security.addProvider(new BouncyCastleProvider());

    // Create some test username and passwords for services
    serviceURI = new URI("http://someservice");
    usernamePassword = new UsernamePassword("testuser", "testpasswd");
    serviceURI2 = new URI("http://someservice2");
    usernamePassword2 = new UsernamePassword("testuser2", "testpasswd2");
    serviceURI3 = new URI("http://someservice3");
    usernamePassword3 = new UsernamePassword("testuser3", "testpasswd3");

    // Load the test private key and its certificate
    File privateKeyCertFile = new File(privateKeyFileURL.getPath());
    KeyStore pkcs12Keystore = java.security.KeyStore.getInstance("PKCS12", "BC"); // We have to use the BC provider here as the certificate chain is not loaded if we use whichever provider is first in Java!!!
    FileInputStream inStream = new FileInputStream(privateKeyCertFile);
    pkcs12Keystore.load(inStream, privateKeyAndPKCS12KeystorePassword.toCharArray());
    // KeyStore pkcs12Keystore = credentialManager.loadPKCS12Keystore(privateKeyCertFile, privateKeyPassword);
    Enumeration<String> aliases = pkcs12Keystore.aliases();
    while (aliases.hasMoreElements()) {
        // The test-private-key-cert.p12 file contains only one private key
        // and corresponding certificate entry
        String alias = aliases.nextElement();
        if (pkcs12Keystore.isKeyEntry(alias)) { // is it a (private) key entry?
            privateKey = pkcs12Keystore.getKey(alias, privateKeyAndPKCS12KeystorePassword.toCharArray());
            privateKeyCertChain = pkcs12Keystore.getCertificateChain(alias);
            break;
        }
    }
    inStream.close();

    // Load the test trusted certificate (belonging to *.Google.com)
    File trustedCertFile = new File(trustedCertficateGoogleFileURL.getPath());
    inStream = new FileInputStream(trustedCertFile);
    CertificateFactory certFactory = CertificateFactory.getInstance("X.509");
    trustedCertficateGoogle = (X509Certificate) certFactory.generateCertificate(inStream);
    try {
        inStream.close();
    } catch (Exception e) {
        // Ignore
    }
    // Load the test trusted certificate (belonging to heater.cs.man.ac.uk)
    File trustedCertFile2 = new File(trustedCertficateHeaterFileURL.getPath());
    inStream = new FileInputStream(trustedCertFile2);
    trustedCertficateHeater = (X509Certificate) certFactory.generateCertificate(inStream);
    try {
        inStream.close();
    } catch (Exception e) {
        // Ignore
    }

    credentialManager = new CredentialManagerImpl();

    //      // The code below sets up the Keystore and Truststore files and loads some data into them
    //      // and saves them into a temp directory. These files can later be used for testing the Credential
    //      // Manager with non-empty keystores.
    //      Random randomGenerator = new Random();
    //      String credentialManagerDirectoryPath = System
    //            .getProperty("java.io.tmpdir")
    //            + System.getProperty("file.separator")
    //            + "taverna-security-"
    //            + randomGenerator.nextInt(1000000);
    //      System.out.println("Credential Manager's directory path: "
    //            + credentialManagerDirectoryPath);
    //      credentialManagerDirectory = new File(credentialManagerDirectoryPath);
    //      credentialManager.setConfigurationDirectoryPath(credentialManagerDirectory);
    //      
    //      // Create the dummy master password provider
    //      masterPasswordProvider = new DummyMasterPasswordProvider();
    //      masterPasswordProvider.setMasterPassword(masterPassword);
    //      List<MasterPasswordProvider> masterPasswordProviders = new ArrayList<MasterPasswordProvider>();
    //      masterPasswordProviders.add(masterPasswordProvider);
    //      credentialManager.setMasterPasswordProviders(masterPasswordProviders);
    //      
    //      // Add some stuff into Credential Manager
    //      credentialManager.addUsernameAndPasswordForService(usernamePassword, serviceURI);
    //      credentialManager.addUsernameAndPasswordForService(usernamePassword2, serviceURI2);
    //      credentialManager.addUsernameAndPasswordForService(usernamePassword3, serviceURI3);
    //      credentialManager.addKeyPair(privateKey, privateKeyCertChain);
    //      credentialManager.addTrustedCertificate(trustedCertficate);

    // Set up a random temp directory and copy the test keystore files 
    // from resources/security
    Random randomGenerator = new Random();
    String credentialManagerDirectoryPath = System.getProperty("java.io.tmpdir")
            + System.getProperty("file.separator") + "taverna-security-" + randomGenerator.nextInt(1000000);
    System.out.println("Credential Manager's directory path: " + credentialManagerDirectoryPath);
    credentialManagerDirectory = new File(credentialManagerDirectoryPath);
    if (!credentialManagerDirectory.exists()) {
        credentialManagerDirectory.mkdir();
    }
    URL keystoreFileURL = CredentialManagerImplIT.class.getResource("/security/t2keystore.ubr");
    File keystoreFile = new File(keystoreFileURL.getPath());
    File keystoreDestFile = new File(credentialManagerDirectory, "taverna-keystore.ubr");
    URL truststroreFileURL = CredentialManagerImplIT.class.getResource("/security/t2truststore.ubr");
    File truststoreFile = new File(truststroreFileURL.getPath());
    File truststoreDestFile = new File(credentialManagerDirectory, "taverna-truststore.ubr");
    FileUtils.copyFile(keystoreFile, keystoreDestFile);
    FileUtils.copyFile(truststoreFile, truststoreDestFile);
    credentialManager.setConfigurationDirectoryPath(credentialManagerDirectory);

    // Create the dummy master password provider
    masterPasswordProvider = new DummyMasterPasswordProvider();
    masterPasswordProvider.setMasterPassword(masterPassword);
    List<MasterPasswordProvider> masterPasswordProviders = new ArrayList<MasterPasswordProvider>();
    masterPasswordProviders.add(masterPasswordProvider);
    credentialManager.setMasterPasswordProviders(masterPasswordProviders);

    // Set an empty list for trust confirmation providers
    credentialManager.setTrustConfirmationProviders(new ArrayList<TrustConfirmationProvider>());

    keystoreChangedObserver = new Observer<KeystoreChangedEvent>() {
        @Override
        public void notify(Observable<KeystoreChangedEvent> sender, KeystoreChangedEvent message)
                throws Exception {
            // TODO Auto-generated method stub
        }
    };
    credentialManager.addObserver(keystoreChangedObserver);
}

From source file:com.ah.ui.actions.home.clientManagement.service.CertificateGenSV.java

public static X509Certificate ananysisP12(InputStream in, char[] keyStorePassword)
        throws KeyStoreException, NoSuchAlgorithmException, CertificateException, IOException {
    KeyStore keyStore = KeyStore.getInstance("PKCS12");
    keyStore.load(in, keyStorePassword);
    in.close();/*from  w  ww  .ja  v a2s  . c o  m*/
    Enumeration<String> enums = keyStore.aliases();
    if (enums.hasMoreElements()) {
        String keyAlis = enums.nextElement();
        X509Certificate certificate = (X509Certificate) keyStore.getCertificate(keyAlis);
        return certificate;
    }
    return null;
}