Android使用KeyStore对数据进行加密的示例代码

publicString encryptString(String needEncryptWord, String alias) {

    if(!"".equals(alias)&&!"".equals(needEncryptWord)){

      if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {

        initKeyStore(alias);

      }

      String encryptStr="";

      byte[] vals=null;

      try{

        KeyStore.PrivateKeyEntry privateKeyEntry = (KeyStore.PrivateKeyEntry)keyStore.getEntry(alias,null);

//      RSAPublicKey publicKey = (RSAPublicKey) privateKeyEntry.getCertificate().getPublicKey();

        if(needEncryptWord.isEmpty()) {

//        Toast.makeText(this, "Enter text in the 'Initial Text' widget", Toast.LENGTH_LONG).show();

          returnencryptStr;

        }

//      Cipher inCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "AndroidOpenSSL");

        Cipher inCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");

//      inCipher.init(Cipher.ENCRYPT_MODE, publicKey);

        inCipher.init(Cipher.ENCRYPT_MODE, privateKeyEntry.getCertificate().getPublicKey());

        ByteArrayOutputStream outputStream =newByteArrayOutputStream();

        CipherOutputStream cipherOutputStream =newCipherOutputStream(

            outputStream, inCipher);

        cipherOutputStream.write(needEncryptWord.getBytes("UTF-8"));

        cipherOutputStream.close();

        vals = outputStream.toByteArray();

      }catch(Exception e) {

        e.printStackTrace();

      }

      returnBase64.encodeToString(vals, Base64.DEFAULT);

    }

    return"";

  }

publicString decryptString(String needDecryptWord, String alias) {

    if(!"".equals(alias)&&!"".equals(needDecryptWord)){

      if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {

        initKeyStore(alias);

      }

      String decryptStr="";

      try{

        KeyStore.PrivateKeyEntry privateKeyEntry = (KeyStore.PrivateKeyEntry)keyStore.getEntry(alias,null);

//      RSAPrivateKey privateKey = (RSAPrivateKey) privateKeyEntry.getPrivateKey();

//      Cipher output = Cipher.getInstance("RSA/ECB/PKCS1Padding", "AndroidOpenSSL");

        Cipher output = Cipher.getInstance("RSA/ECB/PKCS1Padding");

//      output.init(Cipher.DECRYPT_MODE, privateKey);

        output.init(Cipher.DECRYPT_MODE, privateKeyEntry.getPrivateKey());

        CipherInputStream cipherInputStream =newCipherInputStream(

            newByteArrayInputStream(Base64.decode(needDecryptWord, Base64.DEFAULT)), output);

        ArrayListvalues =newArrayList<>();

        intnextByte;

        while((nextByte = cipherInputStream.read()) != -1) {

          values.add((byte)nextByte);

        }

        byte[] bytes =newbyte[values.size()];

        for(inti =0; i < bytes.length; i++) {

          bytes[i] = values.get(i).byteValue();

        }

        decryptStr =newString(bytes,0, bytes.length,"UTF-8");

      }catch(Exception e) {

        e.printStackTrace();

      }

      returndecryptStr;

    }

    return"";

  }