New Secruity namespace added

Move Passwords from Check to Security and deprecate old

Add new SymmetricEncryption and CreateKey

CreateKey class just creates keys for the SymmetricEncryption
SymmetricEncryption uses the hex2bin calls to convert the hex key to the
internal binary key

Example:
$key = CreateKey::generateRandomKey();
$encrypted = SymmetricEncryption::encrypt($string, $key);
$decrypted = SymmetricEncryption::decrypt($encrypted, $key);

Above $key must be stored in some secure location (.env file)

www/lib/CoreLibs/Security/SymmetricEncryption.php

@@ -0,0 +1,96 @@
+<?php
+
+/**
+ * very simple symmetric encryption
+ * Better use: https://paragonie.com/project/halite
+ *
+ * current code is just to encrypt and decrypt
+ *
+ * must use a valid encryption key created with
+ * Secruty\CreateKey class
+ */
+
+declare(strict_types=1);
+
+namespace CoreLibs\Security;
+
+use CoreLibs\Security\CreateKey;
+use SodiumException;
+
+class SymmetricEncryption
+{
+	/**
+	 * Encrypt a message
+	 *
+	 * @param  string $message Message to encrypt
+	 * @param  string $key     Encryption key (as hex string)
+	 * @return string
+	 * @throws \RangeException
+	 */
+	public static function encrypt(string $message, string $key): string
+	{
+		try {
+			$key = CreateKey::hex2bin($key);
+		} catch (SodiumException $e) {
+			throw new \Exception('Invalid hex key');
+		}
+		if (mb_strlen($key, '8bit') !== SODIUM_CRYPTO_SECRETBOX_KEYBYTES) {
+			throw new \RangeException(
+				'Key is not the correct size (must be '
+					. 'SODIUM_CRYPTO_SECRETBOX_KEYBYTES bytes long).'
+			);
+		}
+		$nonce = random_bytes(SODIUM_CRYPTO_SECRETBOX_NONCEBYTES);
+
+		$cipher = base64_encode(
+			$nonce
+			. sodium_crypto_secretbox(
+				$message,
+				$nonce,
+				$key
+			)
+		);
+		sodium_memzero($message);
+		sodium_memzero($key);
+		return $cipher;
+	}
+
+	/**
+	 * Decrypt a message
+	 *
+	 * @param  string $encrypted Message encrypted with safeEncrypt()
+	 * @param  string $key       Encryption key (as hex string)
+	 * @return string
+	 * @throws \Exception
+	 */
+	public static function decrypt(string $encrypted, string $key): string
+	{
+		try {
+			$key = CreateKey::hex2bin($key);
+		} catch (SodiumException $e) {
+			throw new \Exception('Invalid hex key');
+		}
+		$decoded = base64_decode($encrypted);
+		$nonce = mb_substr($decoded, 0, SODIUM_CRYPTO_SECRETBOX_NONCEBYTES, '8bit');
+		$ciphertext = mb_substr($decoded, SODIUM_CRYPTO_SECRETBOX_NONCEBYTES, null, '8bit');
+
+		$plain = false;
+		try {
+			$plain = sodium_crypto_secretbox_open(
+				$ciphertext,
+				$nonce,
+				$key
+			);
+		} catch (SodiumException $e) {
+			throw new \Exception('Invalid ciphertext (too short)');
+		}
+		if (!is_string($plain)) {
+			throw new \Exception('Invalid Key');
+		}
+		sodium_memzero($ciphertext);
+		sodium_memzero($key);
+		return $plain;
+	}
+}
+
+// __END__