Example usage for java.security KeyFactory getInstance

List of usage examples for java.security KeyFactory getInstance

  1. HOME
  2. Java
  3. java
  4. java.security.*
  5. KeyFactory
  6. getInstance

Introduction

In this page you can find the example usage for java.security KeyFactory getInstance.

Prototype

public static KeyFactory getInstance(String algorithm) throws NoSuchAlgorithmException

Source Link

Document

Returns a KeyFactory object that converts public/private keys of the specified algorithm.

Usage

From source file:net.sf.keystore_explorer.crypto.csr.spkac.Spkac.java

private DSAPublicKey decodeDsaPublicKeyFromBitString(DERBitString der, BigInteger p, BigInteger q, BigInteger g)
        throws SpkacException {
    try {// w w  w . jav  a 2 s.  c  om
        BigInteger y = ASN1Integer.getInstance(der.getBytes()).getValue();

        KeyFactory keyFact = KeyFactory.getInstance("DSA");

        return (DSAPublicKey) keyFact.generatePublic(new DSAPublicKeySpec(y, p, q, g));
    } catch (GeneralSecurityException ex) {
        throw new SpkacException(res.getString("NoGenerateDsaPublicKeyFromSpkac.exception.message"), ex);
    } catch (Exception ex) {
        throw new SpkacException(res.getString("NoGenerateDsaPublicKeyFromSpkac.exception.message"), ex);
    }
}

From source file:com.hpe.elderberry.TaxiiConnection.java

/**
 * a convenient way to externally cache the key store is to create it from PEMs using
 * {@link #setPrivateKeyPem(String)} and {@link #setClientCertificatePemChain(List)} then obtaining it with this method and
 * storing it for future use.<p>/*from  w  w w.j  av a2 s .c o  m*/
 * This method attempts to retrieve the key store in the following algorithm:
 * <ul>
 * <li>When it was already loaded or constructed it's returned</li>
 * <li>When it was directly set by {@link #setKeyStore(KeyStore, String)} then this key store is returned</li>
 * <li>When a key store file and password was set by {@link #setKeyStoreFile(File)} and
 * {@link #setKeyStorePassword(String)}, then the key store is loaded from the file and returned</li>
 * <li>When a private key was set by {@link #setPrivateKeyPem(String)} and its certificate chain was set by
 * {@link #setClientCertificatePemChain(List)} then a new key store is created, the private key material and the
 * client certificates are loaded into it, then this new key store is returned</li>
 * </ul>
 *
 * @return the key store
 */
public KeyStore getKeyStore() {
    if (keyStore != null) {
        return keyStore;
    }

    if (keyStoreFile != null) {
        try {
            keyStore = getInstance("JKS");
            keyStore.load(newInputStream(keyStoreFile.toPath()),
                    keyStorePassword == null ? "".toCharArray() : keyStorePassword.toCharArray());
        } catch (Exception e) {
            throw new RuntimeException("a key store file was set, but it could not be read, " + e.getMessage(),
                    e);
        }
    } else if (!isEmpty(privateKeyPem)) {
        try {
            // initialize an empty key store
            keyStore = getInstance("JKS");
            keyStore.load(null);

            // generate a random password for the private key
            keyPassword = randomUUID().toString().toCharArray();

            // load the private key
            byte[] key = parseBase64Binary(privateKeyPem.replaceAll("-+.*-+", ""));
            PrivateKey privateKey = KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(key));
            if (clientCertificatePemChain != null) {
                List<Certificate> chain = addPemsToStore(keyStore, clientCertificatePemChain);
                keyStore.setKeyEntry(randomUUID().toString(), privateKey, keyPassword,
                        chain.toArray(new Certificate[chain.size()]));
            } else {
                keyStore.setKeyEntry(randomUUID().toString(), privateKey, keyPassword, new Certificate[] {});
            }
        } catch (Exception e) {
            throw new RuntimeException("unable to create key store, " + e.getMessage(), e);
        }
    }

    return keyStore;
}

From source file:org.openhab.binding.loxone.internal.core.LxWsSecurityToken.java

private Cipher getRsaCipher(String key) {
    try {//  w  ww.ja  v  a 2 s .co  m
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        String keyString = key.replace("-----BEGIN CERTIFICATE-----", "").replace("-----END CERTIFICATE-----",
                "");
        byte[] keyData = Base64.getDecoder().decode(keyString);
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyData);
        PublicKey publicKey = keyFactory.generatePublic(keySpec);
        logger.debug("[{}] Miniserver public key: {}", debugId, publicKey);
        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.PUBLIC_KEY, publicKey);
        logger.debug("[{}] Initialized RSA public key cipher", debugId);
        return cipher;
    } catch (InvalidKeyException | NoSuchAlgorithmException | NoSuchPaddingException
            | InvalidKeySpecException e) {
        setError(LxOfflineReason.INTERNAL_ERROR, "Exception enabling RSA cipher: " + e.getMessage());
        return null;
    }
}

From source file:org.opensaml.xml.security.SecurityHelper.java

/**
 * Derives the public key from either a DSA or RSA private key.
 * /*  w  ww.j a  v a  2  s .  c om*/
 * @param key the private key to derive the public key from
 * 
 * @return the derived public key
 * 
 * @throws KeyException thrown if the given private key is not a DSA or RSA key or there is a problem generating the
 *             public key
 */
public static PublicKey derivePublicKey(PrivateKey key) throws KeyException {
    KeyFactory factory;
    if (key instanceof DSAPrivateKey) {
        DSAPrivateKey dsaKey = (DSAPrivateKey) key;
        DSAParams keyParams = dsaKey.getParams();
        BigInteger y = keyParams.getQ().modPow(dsaKey.getX(), keyParams.getP());
        DSAPublicKeySpec pubKeySpec = new DSAPublicKeySpec(y, keyParams.getP(), keyParams.getQ(),
                keyParams.getG());

        try {
            factory = KeyFactory.getInstance("DSA");
            return factory.generatePublic(pubKeySpec);
        } catch (GeneralSecurityException e) {
            throw new KeyException("Unable to derive public key from DSA private key", e);
        }
    } else if (key instanceof RSAPrivateCrtKey) {
        RSAPrivateCrtKey rsaKey = (RSAPrivateCrtKey) key;
        RSAPublicKeySpec pubKeySpec = new RSAPublicKeySpec(rsaKey.getModulus(), rsaKey.getPublicExponent());

        try {
            factory = KeyFactory.getInstance("RSA");
            return factory.generatePublic(pubKeySpec);
        } catch (GeneralSecurityException e) {
            throw new KeyException("Unable to derive public key from RSA private key", e);
        }
    } else {
        throw new KeyException("Private key was not a DSA or RSA key");
    }
}

From source file:jef.tools.security.EncrypterUtil.java

/**
 * PKCS8//from   w ww. j  a  v a  2  s  .c o  m
 * 
 * @param f
 * @param algom
 *            
 * @param isPublic
 *            true?false??
 * @return
 */
public static Key loadPKCS8Key(File f, String algom, boolean isPublic) {
    try {
        byte[] keyData = IOUtils.toByteArray(f);
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyData);
        KeyFactory keyFactory = KeyFactory.getInstance(algom);
        Key result = (isPublic) ? keyFactory.generatePublic(keySpec) : keyFactory.generatePrivate(keySpec);
        return result;
    } catch (IOException e) {
        throw new RuntimeException(e);
    } catch (GeneralSecurityException e) {
        throw new RuntimeException(e);
    }
}

From source file:com.linkedin.drelephant.clients.azkaban.AzkabanWorkflowClient.java

/**
 * Decodes the encoded password using the _privateKey
 * @param encodedPassword//w ww. j a v  a2s.  c  o m
 * @param _privateKey
 * @return The decoded password
 * @throws IOException
 * @throws NoSuchAlgorithmException
 * @throws InvalidKeySpecException
 * @throws NoSuchPaddingException
 * @throws InvalidKeyException
 * @throws IllegalBlockSizeException
 * @throws BadPaddingException
 */
private String decodeHeadlessChallenge(String encodedPassword, File _privateKey)
        throws IOException, NoSuchAlgorithmException, InvalidKeySpecException, NoSuchPaddingException,
        InvalidKeyException, IllegalBlockSizeException, BadPaddingException {

    final String RSA = "RSA";
    final String ASCII = "US-ASCII";

    // Read private key from file
    FileInputStream fstream = new FileInputStream(_privateKey);
    byte[] sshPrivateKey = IOUtils.toByteArray(fstream);
    PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(sshPrivateKey);
    KeyFactory kf = KeyFactory.getInstance(RSA);
    PrivateKey privateKey = kf.generatePrivate(keySpec);

    // Init RSA decrypter with private key
    Cipher decryptCipher = Cipher.getInstance(RSA);
    decryptCipher.init(2, privateKey);

    // Convert base 64 password string to raw bytes
    byte[] rawBytes = org.apache.commons.codec.binary.Base64.decodeBase64(encodedPassword.getBytes(ASCII));

    // Decrypt the encoded raw bytes using decrypter
    byte[] decodedBytes = decryptCipher.doFinal(rawBytes);

    // Return decoded bytes as string
    return new String(decodedBytes, ASCII);
}

From source file:com.jrummyapps.busybox.signing.ZipSigner.java

/** Read a PKCS 8 format private key. */
private static PrivateKey readPrivateKey(InputStream file) throws IOException, GeneralSecurityException {
    final DataInputStream input = new DataInputStream(file);
    try {/* w ww .  jav  a 2s . co  m*/
        byte[] bytes = new byte[10000];
        int nBytesTotal = 0, nBytes;
        while ((nBytes = input.read(bytes, nBytesTotal, 10000 - nBytesTotal)) != -1) {
            nBytesTotal += nBytes;
        }

        final byte[] bytes2 = new byte[nBytesTotal];
        System.arraycopy(bytes, 0, bytes2, 0, nBytesTotal);
        bytes = bytes2;

        KeySpec spec = decryptPrivateKey(bytes);
        if (spec == null) {
            spec = new PKCS8EncodedKeySpec(bytes);
        }

        try {
            return KeyFactory.getInstance("RSA").generatePrivate(spec);
        } catch (final InvalidKeySpecException ex) {
            return KeyFactory.getInstance("DSA").generatePrivate(spec);
        }
    } finally {
        input.close();
    }
}

From source file:net.sourceforge.msscodefactory.cfasterisk.v2_4.CFAsteriskSMWar.CFAsteriskSMWarAddDeviceHtml.java

/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 *//*w  ww . j a va2s . c  o m*/
protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    final String S_ProcName = "doPost";

    ICFAsteriskSchemaObj schemaObj;
    HttpSession sess = request.getSession(false);
    if (sess == null) {
        sess = request.getSession(true);
        schemaObj = new CFAsteriskSchemaPooledObj();
        sess.setAttribute("SchemaObj", schemaObj);
    } else {
        schemaObj = (ICFAsteriskSchemaObj) sess.getAttribute("SchemaObj");
        if (schemaObj == null) {
            response.sendRedirect("CFAsteriskSMWarLoginHtml");
            return;
        }
    }

    CFSecurityAuthorization auth = schemaObj.getAuthorization();
    if (auth == null) {
        response.sendRedirect("CFAsteriskSMWarLoginHtml");
        return;
    }

    ICFSecuritySecUserObj secUser = null;
    ICFSecurityClusterObj secCluster = null;
    String clusterDescription = "";

    ICFAsteriskSchema dbSchema = null;
    try {
        dbSchema = (ICFAsteriskSchema) CFAsteriskSchemaPool.getSchemaPool().getInstance();
        schemaObj.setBackingStore(dbSchema);
        schemaObj.beginTransaction();

        secUser = schemaObj.getSecUserTableObj().readSecUserByIdIdx(auth.getSecUserId());

        secCluster = schemaObj.getClusterTableObj().readClusterByIdIdx(auth.getSecClusterId());
        if (secCluster == null) {
            throw CFLib.getDefaultExceptionFactory().newNullArgumentException(getClass(), S_ProcName, 0,
                    "secCluster");
        }
        clusterDescription = secCluster.getRequiredDescription();

        String deviceName = request.getParameter("DeviceName");
        if ((deviceName == null) || (deviceName.length() <= 0)) {
            response.setContentType("text/html");
            PrintWriter out = response.getWriter();
            out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\">");
            out.println("<HTML>");
            out.println("<BODY>");
            out.println("<form method=\"post\" formaction=\"CFAsteriskSMWarAddDeviceHtml\">");
            out.println("<H1 style=\"text-align:center\">" + clusterDescription + " Security Manager</H1>");
            out.println("<H2 style=\"text-align:center\">ERROR</H2>");
            out.println("<p style=\"text-align:center\">Device Name must be specified.");
            out.println("<H2 style=\"text-align:center\">Add new device for "
                    + secUser.getRequiredEMailAddress() + "</H2>");
            out.println("<p>");
            out.println("<table style=\"width:90%\">");
            out.println(
                    "<tr><th style=\"text-align:left\">Device Name:</th><td><input type=\"text\" name=\"DeviceName\"/></td></tr>");
            out.println(
                    "<tr><th style=\"text-align:left\">Public Key:</th><td><textarea name=\"PublicKey\" cols=\"60\" rows=\"10\"></textarea></td></tr>");
            out.println("</table>");
            out.println(
                    "<p style=\"text-align:center\"><button type=\"submit\" name=\"Ok\"\">Add Device</button>&nbsp;&nbsp;&nbsp;&nbsp;<button type=\"button\" name=\"Cancel\"\" onclick=\"window.location.href='CFAsteriskSMWarSecurityMainHtml'\">Cancel</button>");
            out.println("</form>");
            out.println("</BODY>");
            out.println("</HTML>");
            return;
        }

        ICFSecuritySecDeviceObj secDev = schemaObj.getSecDeviceTableObj()
                .readSecDeviceByIdIdx(secUser.getRequiredSecUserId(), deviceName);
        if (secDev != null) {
            response.setContentType("text/html");
            PrintWriter out = response.getWriter();
            out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\">");
            out.println("<HTML>");
            out.println("<BODY>");
            out.println("<form method=\"post\" formaction=\"CFAsteriskSMWarAddDeviceHtml\">");
            out.println("<H1 style=\"text-align:center\">" + clusterDescription + " Security Manager</H1>");
            out.println("<H2 style=\"text-align:center\">ERROR</H2>");
            out.println("<p style=\"text-align:center\">Device Name \"" + deviceName + "\" already in use.");
            out.println("<H2 style=\"text-align:center\">Add new device for "
                    + secUser.getRequiredEMailAddress() + "</H2>");
            out.println("<p>");
            out.println("<table style=\"width:90%\">");
            out.println(
                    "<tr><th style=\"text-align:left\">Device Name:</th><td><input type=\"text\" name=\"DeviceName\"/></td></tr>");
            out.println(
                    "<tr><th style=\"text-align:left\">Public Key:</th><td><textarea name=\"PublicKey\" cols=\"60\" rows=\"10\"></textarea></td></tr>");
            out.println("</table>");
            out.println(
                    "<p style=\"text-align:center\"><button type=\"submit\" name=\"Ok\"\">Add Device</button>&nbsp;&nbsp;&nbsp;&nbsp;<button type=\"button\" name=\"Cancel\"\" onclick=\"window.location.href='CFAsteriskSMWarSecurityMainHtml'\">Cancel</button>");
            out.println("</form>");
            out.println("</BODY>");
            out.println("</HTML>");
            return;
        }

        String publicKey = request.getParameter("PublicKey");
        if ((publicKey == null) || (publicKey.length() <= 0)) {
            response.setContentType("text/html");
            PrintWriter out = response.getWriter();
            out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\">");
            out.println("<HTML>");
            out.println("<BODY>");
            out.println("<form method=\"post\" formaction=\"CFAsteriskSMWarAddDeviceHtml\">");
            out.println("<H1 style=\"text-align:center\">" + clusterDescription + " Security Manager</H1>");
            out.println("<p style=\"text-align:center\">Public Key must be specified.");
            out.println("<H2 style=\"text-align:center\">Add new device for "
                    + secUser.getRequiredEMailAddress() + "</H2>");
            out.println("<p>");
            out.println("<table style=\"width:90%\">");
            out.println(
                    "<tr><th style=\"text-align:left\">Device Name:</th><td><input type=\"text\" name=\"DeviceName\"/></td></tr>");
            out.println(
                    "<tr><th style=\"text-align:left\">Public Key:</th><td><textarea name=\"PublicKey\" cols=\"60\" rows=\"10\"></textarea></td></tr>");
            out.println("</table>");
            out.println(
                    "<p style=\"text-align:center\"><button type=\"submit\" name=\"Ok\"\">Add Device</button>&nbsp;&nbsp;&nbsp;&nbsp;<button type=\"button\" name=\"Cancel\"\" onclick=\"window.location.href='CFAsteriskSMWarSecurityMainHtml'\">Cancel</button>");
            out.println("</form>");
            out.println("</BODY>");
            out.println("</HTML>");
            return;
        }

        byte wrapped[] = Base64.decodeBase64(publicKey);

        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(wrapped);
        KeyFactory kf = KeyFactory.getInstance("RSA");
        if (kf == null) {
            throw CFLib.getDefaultExceptionFactory().newNullArgumentException(getClass(), S_ProcName, 0, "kf");
        }

        PublicKey decodedPublicKey = kf.generatePublic(x509KeySpec);
        if (decodedPublicKey == null) {
            response.setContentType("text/html");
            PrintWriter out = response.getWriter();
            out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\">");
            out.println("<HTML>");
            out.println("<BODY>");
            out.println("<form method=\"post\" formaction=\"CFAsteriskSMWarAddDeviceHtml\">");
            out.println("<H1 style=\"text-align:center\">" + clusterDescription + " Security Manager</H1>");
            out.println("<p style=\"text-align:center\">Public Key must be a valid RSA 2048 Key.");
            out.println("<H2 style=\"text-align:center\">Add new device for "
                    + secUser.getRequiredEMailAddress() + "</H2>");
            out.println("<p>");
            out.println("<table style=\"width:90%\">");
            out.println(
                    "<tr><th style=\"text-align:left\">Device Name:</th><td><input type=\"text\" name=\"DeviceName\"/></td></tr>");
            out.println(
                    "<tr><th style=\"text-align:left\">Public Key:</th><td><textarea name=\"PublicKey\" cols=\"60\" rows=\"10\"></textarea></td></tr>");
            out.println("</table>");
            out.println(
                    "<p style=\"text-align:center\"><button type=\"submit\" name=\"Ok\"\">Add Device</button>&nbsp;&nbsp;&nbsp;&nbsp;<button type=\"button\" name=\"Cancel\"\" onclick=\"window.location.href='CFAsteriskSMWarSecurityMainHtml'\">Cancel</button>");
            out.println("</form>");
            out.println("</BODY>");
            out.println("</HTML>");
            return;
        }

        ICFSecurityClusterObj systemCluster = schemaObj.getClusterTableObj()
                .readClusterByUDomainNameIdx("system");
        ICFSecurityTenantObj systemTenant = schemaObj.getTenantTableObj()
                .readTenantByUNameIdx(systemCluster.getRequiredId(), "system");
        ICFSecuritySecUserObj systemUser = schemaObj.getSecUserTableObj().readSecUserByULoginIdx("system");
        ICFSecuritySecSessionObj systemSession = schemaObj.getSecSessionTableObj().newInstance();
        ICFSecuritySecSessionEditObj editSystemSession = (ICFSecuritySecSessionEditObj) systemSession
                .beginEdit();
        editSystemSession.setRequiredContainerSecUser(systemUser);
        editSystemSession.setRequiredStart(Calendar.getInstance());
        systemSession = editSystemSession.create();
        editSystemSession.endEdit();

        CFSecurityAuthorization secAuth = new CFSecurityAuthorization();
        secAuth.setSecCluster(systemCluster);
        secAuth.setSecTenant(systemTenant);
        secAuth.setSecSession(systemSession);
        schemaObj.setAuthorization(secAuth);

        secDev = schemaObj.getSecDeviceTableObj().newInstance();
        ICFSecuritySecDeviceEditObj editDev = secDev.beginEdit();
        editDev.setRequiredContainerSecUser(secUser);
        editDev.setRequiredDevName(deviceName);
        editDev.setOptionalPubKey(publicKey);
        secDev = editDev.create();
        editDev.endEdit();

        if (null == secUser.getOptionalLookupDefDev()) {
            ICFSecuritySecUserEditObj editSecUser = secUser.beginEdit();
            editSecUser.setOptionalLookupDefDev(secDev);
            editSecUser.update();
            editSecUser.endEdit();
        }

        editSystemSession = (ICFSecuritySecSessionEditObj) systemSession.beginEdit();
        editSystemSession.setOptionalFinish(Calendar.getInstance());
        editSystemSession.update();
        editSystemSession.endEdit();

        schemaObj.commit();

        schemaObj.setAuthorization(auth);

        response.sendRedirect("CFAsteriskSMWarSecurityMainHtml");

    } catch (InvalidKeySpecException e) {
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\">");
        out.println("<HTML>");
        out.println("<BODY>");
        out.println("<form method=\"post\" formaction=\"CFAsteriskSMWarAddDeviceHtml\">");
        out.println("<H1 style=\"text-align:center\">" + clusterDescription + " Security Manager</H1>");
        out.println("<p style=\"text-align:center\">Public Key must be a valid RSA 2048 Key.");
        out.println("<H2 style=\"text-align:center\">Add new device for " + secUser.getRequiredEMailAddress()
                + "</H2>");
        out.println("<p>");
        out.println("<table style=\"width:90%\">");
        out.println(
                "<tr><th style=\"text-align:left\">Device Name:</th><td><input type=\"text\" name=\"DeviceName\"/></td></tr>");
        out.println(
                "<tr><th style=\"text-align:left\">Public Key:</th><td><textarea name=\"PublicKey\" cols=\"60\" rows=\"10\"></textarea></td></tr>");
        out.println("</table>");
        out.println(
                "<p style=\"text-align:center\"><button type=\"submit\" name=\"Ok\"\">Add Device</button>&nbsp;&nbsp;&nbsp;&nbsp;<button type=\"button\" name=\"Cancel\"\" onclick=\"window.location.href='CFAsteriskSMWarSecurityMainHtml'\">Cancel</button>");
        out.println("</form>");
        out.println("</BODY>");
        out.println("</HTML>");
    } catch (NoSuchAlgorithmException e) {
        throw CFLib.getDefaultExceptionFactory().newRuntimeException(getClass(), S_ProcName,
                "Caught NoSuchAlgorithmException -- " + e.getMessage(), e);
    } catch (RuntimeException e) {
        throw CFLib.getDefaultExceptionFactory().newRuntimeException(getClass(), S_ProcName,
                "Caught RuntimeException -- " + e.getMessage(), e);
    } finally {
        schemaObj.setAuthorization(auth);
        if (dbSchema != null) {
            try {
                if (schemaObj.isTransactionOpen()) {
                    schemaObj.rollback();
                }
            } catch (RuntimeException e) {
            }
            schemaObj.setBackingStore(null);
            CFAsteriskSchemaPool.getSchemaPool().releaseInstance(dbSchema);
        }
    }
}

From source file:org.opendatakit.survey.android.utilities.EncryptionUtils.java

/**
 * Retrieve the encryption information for this row.
 * //from   w  ww .j  a va 2  s. c om
 * @param appName
 * @param tableId
 * @param xmlBase64RsaPublicKey
 * @param instanceId
 * @return
 */
public static EncryptedFormInformation getEncryptedFormInformation(String appName, String tableId,
        String xmlBase64RsaPublicKey, String instanceId) {

    // fetch the form information
    String base64RsaPublicKey = xmlBase64RsaPublicKey;
    PublicKey pk;
    Base64Wrapper wrapper;

    if (base64RsaPublicKey == null || base64RsaPublicKey.length() == 0) {
        return null; // this is legitimately not an encrypted form
    }

    // submission must have an OpenRosa metadata block with a non-null
    // instanceID value.
    if (instanceId == null) {
        WebLogger.getLogger(appName).e(t, "No OpenRosa metadata block or no instanceId defined in that block");
        return null;
    }

    int version = android.os.Build.VERSION.SDK_INT;
    if (version < 8) {
        WebLogger.getLogger(appName).e(t, "Phone does not support encryption.");
        return null; // save unencrypted
    }

    // this constructor will throw an exception if we are not
    // running on version 8 or above (if Base64 is not found).
    try {
        wrapper = new Base64Wrapper();
    } catch (ClassNotFoundException e) {
        WebLogger.getLogger(appName).e(t, "Phone does not have Base64 class but API level is " + version);
        WebLogger.getLogger(appName).printStackTrace(e);
        return null; // save unencrypted
    }

    // OK -- Base64 decode (requires API Version 8 or higher)
    byte[] publicKey = wrapper.decode(base64RsaPublicKey);
    X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKey);
    KeyFactory kf;
    try {
        kf = KeyFactory.getInstance(RSA_ALGORITHM);
    } catch (NoSuchAlgorithmException e) {
        WebLogger.getLogger(appName).e(t, "Phone does not support RSA encryption.");
        WebLogger.getLogger(appName).printStackTrace(e);
        return null;
    }
    try {
        pk = kf.generatePublic(publicKeySpec);
    } catch (InvalidKeySpecException e) {
        WebLogger.getLogger(appName).printStackTrace(e);
        WebLogger.getLogger(appName).e(t, "Invalid RSA public key.");
        return null;
    }
    return new EncryptedFormInformation(appName, tableId, xmlBase64RsaPublicKey, instanceId, pk, wrapper);
}

From source file:com.trsst.Common.java

/**
 * Converts a X509-encoded EC key to a PublicKey.
 *//*w  ww  .j a va  2s  .c o  m*/
public static PublicKey toPublicKeyFromX509(String stored) throws GeneralSecurityException {
    KeyFactory factory = KeyFactory.getInstance("EC");
    byte[] data = Base64.decodeBase64(stored);
    X509EncodedKeySpec spec = new X509EncodedKeySpec(data);
    return factory.generatePublic(spec);

}