--- /dev/null
+package be.nikiroo.utils;
+
+import java.io.IOException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+
+import javax.crypto.BadPaddingException;
+import javax.crypto.Cipher;
+import javax.crypto.IllegalBlockSizeException;
+import javax.crypto.NoSuchPaddingException;
+import javax.crypto.SecretKey;
+import javax.crypto.spec.SecretKeySpec;
+
+/**
+ * Small utility class to do AES encryption/decryption.
+ * <p>
+ * Do not assume it is actually secure until you checked the code...
+ *
+ * @author niki
+ */
+public class CryptUtils {
+ private Cipher ecipher;
+ private Cipher dcipher;
+
+ /**
+ * Small and leazy way to initialize a 128 bits key with {@link CryptUtils}.
+ * <p>
+ * <b>Some</b> part of the key will be used to generate a 128 bits key and
+ * initialize the {@link CryptUtils}; even NULL will generate something.
+ * <p>
+ * <b>This is most probably not secure. Do not use if you actually care
+ * about security.</b>
+ *
+ * @param key
+ * the {@link String} to use as a base for the key, can be NULL
+ */
+ public CryptUtils(String key) {
+ try {
+ init(key2key(key));
+ } catch (InvalidKeyException e) {
+ // We made sure that the key is correct, so nothing here
+ e.printStackTrace();
+ }
+ }
+
+ /**
+ * Create a new instance of {@link CryptUtils} with the given 128 bytes key.
+ * <p>
+ * The key <b>must</b> be exactly 128 bytes long.
+ *
+ * @param bytes32
+ * the 128 bits (32 bytes) of the key
+ *
+ * @throws InvalidKeyException
+ * if the key is not an array of 128 bytes
+ */
+ public CryptUtils(byte[] bytes32) throws InvalidKeyException {
+ init(bytes32);
+ }
+
+ /**
+ * This method required an array of 128 bytes.
+ *
+ * @param bytes32
+ * the array, which <b>must</b> be of 128 bits (32 bytes)
+ *
+ * @throws InvalidKeyException
+ * if the key is not an array of 128 bits (32 bytes)
+ */
+ private void init(byte[] bytes32) throws InvalidKeyException {
+ if (bytes32 == null || bytes32.length != 32) {
+ throw new InvalidKeyException(
+ "The size of the key must be of 128 bits (32 bytes), it is: "
+ + (bytes32 == null ? "null" : "" + bytes32.length)
+ + " bytes");
+ }
+
+ SecretKey key = new SecretKeySpec(bytes32, "AES");
+ try {
+ ecipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
+ dcipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
+ ecipher.init(Cipher.ENCRYPT_MODE, key);
+ dcipher.init(Cipher.DECRYPT_MODE, key);
+ } catch (NoSuchAlgorithmException e) {
+ // Every implementation of the Java platform is required to support
+ // this standard Cipher transformation with 128 bits keys
+ e.printStackTrace();
+ } catch (NoSuchPaddingException e) {
+ // Every implementation of the Java platform is required to support
+ // this standard Cipher transformation with 128 bits keys
+ e.printStackTrace();
+ } catch (InvalidKeyException e) {
+ // Every implementation of the Java platform is required to support
+ // this standard Cipher transformation with 128 bits keys
+ e.printStackTrace();
+ }
+ }
+
+ /**
+ * Encrypt the data.
+ *
+ * @param data
+ * the data to encrypt
+ *
+ * @return the encrypted data
+ *
+ * @throws IOException
+ * in case of I/O error (i.e., the data is not what you assumed
+ * it was)
+ */
+ public byte[] encrypt(byte[] data) throws IOException {
+ try {
+ return ecipher.doFinal(data);
+ } catch (IllegalBlockSizeException e) {
+ throw new IOException(e);
+ } catch (BadPaddingException e) {
+ throw new IOException(e);
+ }
+ }
+
+ /**
+ * Encrypt the data.
+ *
+ * @param data
+ * the data to encrypt
+ *
+ * @return the encrypted data
+ *
+ * @throws IOException
+ * in case of I/O error (i.e., the data is not what you assumed
+ * it was)
+ */
+ public byte[] encrypt(String data) throws IOException {
+ return encrypt(data.getBytes("UTF8"));
+ }
+
+ /**
+ * Encrypt the data, then encode it into Base64.
+ *
+ * @param data
+ * the data to encrypt
+ * @param zip
+ * TRUE to also compress the data in GZIP format; remember that
+ * compressed and not-compressed content are different; you need
+ * to know which is which when decoding
+ *
+ * @return the encrypted data, encoded in Base64
+ *
+ * @throws IOException
+ * in case of I/O error (i.e., the data is not what you assumed
+ * it was)
+ */
+ public String encrypt64(String data, boolean zip) throws IOException {
+ return encrypt64(data.getBytes("UTF8"), zip);
+ }
+
+ /**
+ * Encrypt the data, then encode it into Base64.
+ *
+ * @param data
+ * the data to encrypt
+ * @param zip
+ * TRUE to also compress the data in GZIP format; remember that
+ * compressed and not-compressed content are different; you need
+ * to know which is which when decoding
+ *
+ * @return the encrypted data, encoded in Base64
+ *
+ * @throws IOException
+ * in case of I/O error (i.e., the data is not what you assumed
+ * it was)
+ */
+ public String encrypt64(byte[] data, boolean zip) throws IOException {
+ return StringUtils.base64(encrypt(data), zip);
+ }
+
+ /**
+ * Decode the data which is assumed to be encrypted with the same utilities.
+ *
+ * @param data
+ * the encrypted data to decode
+ *
+ * @return the original, decoded data
+ *
+ * @throws IOException
+ * in case of I/O error
+ */
+ public byte[] decrypt(byte[] data) throws IOException {
+ try {
+ return dcipher.doFinal(data);
+ } catch (IllegalBlockSizeException e) {
+ throw new IOException(e);
+ } catch (BadPaddingException e) {
+ throw new IOException(e);
+ }
+ }
+
+ /**
+ * Decode the data which is assumed to be encrypted with the same utilities
+ * and is a Base64 encoded value.
+ *
+ * @param data
+ * the encrypted data to decode in Base64 format
+ * @param zip
+ * TRUE to also uncompress the data from a GZIP format
+ * automatically; if set to FALSE, zipped data can be returned
+ *
+ * @return the original, decoded data
+ *
+ * @throws IOException
+ * in case of I/O error
+ */
+ public byte[] decrypt64(String data, boolean zip) throws IOException {
+ return decrypt(StringUtils.unbase64(data, zip));
+ }
+
+ /**
+ * Decode the data which is assumed to be encrypted with the same utilities
+ * and is a Base64 encoded value, then convert it into a String (this method
+ * assumes the data <b>was</b> indeed a UTF-8 encoded {@link String}).
+ *
+ * @param data
+ * the encrypted data to decode in Base64 format
+ * @param zip
+ * TRUE to also uncompress the data from a GZIP format
+ * automatically; if set to FALSE, zipped data can be returned
+ *
+ * @return the original, decoded data
+ *
+ * @throws IOException
+ * in case of I/O error
+ */
+ public String decrypt64s(String data, boolean zip) throws IOException {
+ return new String(decrypt(StringUtils.unbase64(data, zip)), "UTF-8");
+ }
+
+ /**
+ * This is probably <b>NOT</b> secure!
+ *
+ * @param input
+ * some {@link String} input
+ *
+ * @return a 128 bits key computed from the given input
+ */
+ static private byte[] key2key(String input) {
+ return StringUtils.getMd5Hash(input).getBytes();
+ }
+}
git://git.nikiroo.be / nikiroo-utils.git / commitdiff