diff --git a/stubs/crypto.php b/stubs/crypto.php
new file mode 100644
index 0000000..de724f7
--- /dev/null
+++ b/stubs/crypto.php
@@ -0,0 +1,781 @@
+<?php
+
+namespace Crypto{
+
+/**
+ * Class providing cipher algorithms
+ */
+class Cipher {
+    const MODE_ECB = 1;
+    const MODE_CBC = 2;
+    const MODE_CFB = 3;
+    const MODE_OFB = 4;
+    const MODE_CTR = 5;
+    const MODE_GCM = 6;
+    const MODE_CCM = 7;
+    const MODE_XTS = 65537;
+    
+    /**
+     * Returns cipher algorithms
+     * @param bool $aliases
+     * @param string $prefix
+     * @return string
+     */
+    public static function getAlgorithms($aliases = false, $prefix = null) {}
+    
+    /**
+     * Finds out whether algorithm exists
+     * @param string $algorithm
+     * @return bool
+     */
+    public static function hasAlgorithm($algorithm) {}
+    
+    /**
+     * Finds out whether the cipher mode is defined in the used OpenSSL library
+     * @param int $mode
+     * @return bool
+     */
+    public static function hasMode($mode) {}
+    
+    /**
+     * Cipher magic method for calling static methods
+     * @param string $name
+     * @param array $arguments
+     */
+    public static function __callStatic($name, $arguments) {}
+    
+    /**
+     * Cipher constructor
+     * @param string $algorithm
+     * @param int $mode
+     * @param string $key_size
+     */
+    public function __construct($algorithm, $mode = NULL, $key_size = NULL) {}
+    
+    /**
+     * Returns cipher algorithm string
+     * @return string
+     */
+    public function getAlgorithmName() {}
+    
+    /**
+     * Initializes cipher encryption
+     * @param string $key
+     * @param string $iv
+     * @return bool
+     */
+    public function encryptInit($key, $iv = null) {}
+    
+    /**
+     * Updates cipher encryption
+     * @param string $data
+     * @return string
+     */
+    public function encryptUpdate($data) {}
+    
+    /**
+     * Finalizes cipher encryption
+     * @return string
+     */
+    public function encryptFinish() {}
+    
+    /**
+     * Encrypts text to ciphertext
+     * @param string $data
+     * @param string $key
+     * @param string $iv
+     * @return string
+     */
+    public function encrypt($data, $key, $iv = null) {}
+    
+    /**
+     * Initializes cipher decryption
+     * @param string $key
+     * @param string $iv
+     * @return null
+     */
+    public function decryptInit($key, $iv = null) {}
+    
+    /**
+     * Updates cipher decryption
+     * @param string $data
+     * @return string
+     */
+    public function decryptUpdate($data) {}
+    
+    /**
+     * Finalizes cipher decryption
+     * @return string
+     */
+    public function decryptFinish() {}
+    
+    /**
+     * Decrypts ciphertext to decrypted text
+     * @param string $data
+     * @param string $key
+     * @param string $iv
+     * @return string
+     */
+    public function decrypt($data, $key, $iv = null) {}
+    
+    /**
+     * Returns cipher block size
+     * @return int
+     */
+    public function getBlockSize() {}
+    
+    /**
+     * Returns cipher key length
+     * @return int
+     */
+    public function getKeyLength() {}
+    
+    /**
+     * Returns cipher IV length
+     * @return int
+     */
+    public function getIVLength() {}
+    
+    /**
+     * Returns cipher mode
+     * @return int
+     */
+    public function getMode() {}
+    
+    /**
+     * Returns authentication tag
+     * @return string
+     */
+    public function getTag() {}
+    
+    /**
+     * Sets authentication tag
+     * @param string $tag
+     * @return bool
+     */
+    public function setTag($tag) {}
+    
+    /**
+     * Set authentication tag length
+     * @param int $tag_length
+     * @return bool
+     */
+    public function setTagLength($tag_length) {}
+    
+    /**
+     * Sets additional application data for authenticated encryption
+     * @param string $aad
+     * @return bool
+     */
+    public function setAAD($aad) {}
+    
+}
+
+/**
+ * Exception class for cipher errors
+ */
+class CipherException extends \Exception {
+    
+    /**
+     * Cipher '%s' algorithm not found
+     */
+    const ALGORITHM_NOT_FOUND = 1;
+    
+    /**
+     * Cipher static method '%s' not found
+     */
+    const STATIC_METHOD_NOT_FOUND = 2;
+    
+    /**
+     * Cipher static method %s can accept max two arguments
+     */
+    const STATIC_METHOD_TOO_MANY_ARGS = 3;
+    
+    /**
+     * Cipher mode not found
+     */
+    const MODE_NOT_FOUND = 4;
+    
+    /**
+     * Cipher mode %s is not available in installed OpenSSL library
+     */
+    const MODE_NOT_AVAILABLE = 5;
+    
+    /**
+     * The authentication is not supported for %s cipher mode
+     */
+    const AUTHENTICATION_NOT_SUPPORTED = 6;
+    
+    /**
+     * Invalid length of key for cipher '%s' algorithm (required length: %d)
+     */
+    const KEY_LENGTH_INVALID = 7;
+    
+    /**
+     * Invalid length of initial vector for cipher '%s' algorithm (required length: %d)
+     */
+    const IV_LENGTH_INVALID = 8;
+    
+    /**
+     * AAD setter has to be called before encryption or decryption
+     */
+    const AAD_SETTER_FORBIDDEN = 9;
+    
+    /**
+     * AAD setter failed
+     */
+    const AAD_SETTER_FAILED = 10;
+    
+    /**
+     * AAD length can't exceed max integer length
+     */
+    const AAD_LENGTH_HIGH = 11;
+    
+    /**
+     * Tag getter has to be called after encryption
+     */
+    const TAG_GETTER_FORBIDDEN = 12;
+    
+    /**
+     * Tag setter has to be called before decryption
+     */
+    const TAG_SETTER_FORBIDDEN = 13;
+    
+    /**
+     * Tag getter failed
+     */
+    const TAG_GETTER_FAILED = 14;
+    
+    /**
+     * Tag setter failed
+     */
+    const TAG_SETTER_FAILED = 15;
+    
+    /**
+     * Tag length setter has to be called before encryption
+     */
+    const TAG_LENGTH_SETTER_FORBIDDEN = 16;
+    
+    /**
+     * Tag length can't be lower than 32 bits (4 characters)
+     */
+    const TAG_LENGTH_LOW = 17;
+    
+    /**
+     * Tag length can't exceed 128 bits (16 characters)
+     */
+    const TAG_LENGTH_HIGH = 18;
+    
+    /**
+     * Tag verification failed
+     */
+    const TAG_VERIFY_FAILED = 19;
+    
+    /**
+     * Initialization of cipher algorithm failed
+     */
+    const INIT_ALG_FAILED = 20;
+    
+    /**
+     * Initialization of cipher context failed
+     */
+    const INIT_CTX_FAILED = 21;
+    
+    /**
+     * Cipher object is already used for decryption
+     */
+    const INIT_ENCRYPT_FORBIDDEN = 22;
+    
+    /**
+     * Cipher object is already used for encryption
+     */
+    const INIT_DECRYPT_FORBIDDEN = 23;
+    
+    /**
+     * Updating of cipher failed
+     */
+    const UPDATE_FAILED = 24;
+    
+    /**
+     * Cipher object is not initialized for encryption
+     */
+    const UPDATE_ENCRYPT_FORBIDDEN = 25;
+    
+    /**
+     * Cipher object is not initialized for decryption
+     */
+    const UPDATE_DECRYPT_FORBIDDEN = 26;
+    
+    /**
+     * Finalizing of cipher failed
+     */
+    const FINISH_FAILED = 27;
+    
+    /**
+     * Cipher object is not initialized for encryption
+     */
+    const FINISH_ENCRYPT_FORBIDDEN = 28;
+    
+    /**
+     * Cipher object is not initialized for decryption
+     */
+    const FINISH_DECRYPT_FORBIDDEN = 29;
+    
+    /**
+     * Input data length can't exceed max integer length
+     */
+    const INPUT_DATA_LENGTH_HIGH = 30;
+    
+}
+
+/**
+ * Class providing hash algorithms
+ */
+class Hash {
+    /**
+     * Returns hash algorithms
+     * @param bool $aliases
+     * @param string $prefix
+     * @return string
+     */
+    public static function getAlgorithms($aliases = false, $prefix = null) {}
+    
+    /**
+     * Finds out whether algorithm exists
+     * @param string $algorithm
+     * @return bool
+     */
+    public static function hasAlgorithm($algorithm) {}
+    
+    /**
+     * Hash magic method for calling static methods
+     * @param string $name
+     * @param array $arguments
+     */
+    public static function __callStatic($name, $arguments) {}
+    
+    /**
+     * Hash constructor
+     * @param string $algorithm
+     */
+    public function __construct($algorithm) {}
+    
+    /**
+     * Returns hash algorithm string
+     * @return string
+     */
+    public function getAlgorithmName() {}
+    
+    /**
+     * Updates hash
+     * @param string $data
+     * @return null
+     */
+    public function update($data) {}
+    
+    /**
+     * Return hash digest in raw foramt
+     * @return string
+     */
+    public function digest() {}
+    
+    /**
+     * Return hash digest in hex format
+     * @return string
+     */
+    public function hexdigest() {}
+    
+    /**
+     * Returns hash block size
+     * @return int
+     */
+    public function getBlockSize() {}
+    
+    /**
+     * Returns hash size
+     * @return int
+     */
+    public function getSize() {}
+    
+}
+
+/**
+ * Exception class for hash errors
+ */
+class HashException extends \Exception {
+    
+    /**
+     * Hash algorithm '%s' not found
+     */
+    const HASH_ALGORITHM_NOT_FOUND = 1;
+    
+    /**
+     * Hash static method '%s' not found
+     */
+    const STATIC_METHOD_NOT_FOUND = 2;
+    
+    /**
+     * Hash static method %s can accept max one argument
+     */
+    const STATIC_METHOD_TOO_MANY_ARGS = 3;
+    
+    /**
+     * Initialization of hash failed
+     */
+    const INIT_FAILED = 4;
+    
+    /**
+     * Updating of hash context failed
+     */
+    const UPDATE_FAILED = 5;
+    
+    /**
+     * Creating of hash digest failed
+     */
+    const DIGEST_FAILED = 6;
+    
+    /**
+     * Input data length can't exceed max integer length
+     */
+    const INPUT_DATA_LENGTH_HIGH = 7;
+    
+}
+
+/**
+ * Abstract class for MAC subclasses
+ */
+abstract class MAC extends Hash {
+    /**
+     * Create a MAC (used by MAC subclasses - HMAC and CMAC)
+     * @param string $algorithm
+     * @param string $key
+     */
+    public function __construct($algorithm, $key) {}
+    
+}
+
+/**
+ * Exception class for MAC errors
+ */
+class MACException extends HashException {
+    
+    /**
+     * MAC algorithm '%s' not found
+     */
+    const MAC_ALGORITHM_NOT_FOUND = 1;
+    
+    /**
+     * The key length for MAC is invalid
+     */
+    const KEY_LENGTH_INVALID = 2;
+    
+}
+
+/**
+ * Class providing HMAC functionality
+ */
+class HMAC extends MAC {
+}
+
+/**
+ * Class providing CMAC functionality
+ */
+class CMAC extends MAC {
+}
+
+/**
+ * Abstract class for KDF subclasses
+ */
+abstract class KDF {
+    /**
+     * KDF constructor
+     * @param int $length
+     * @param string $salt
+     */
+    public function __construct($length, $salt = NULL) {}
+    
+    /**
+     * Get key length
+     * @return int
+     */
+    public function getLength() {}
+    
+    /**
+     * Set key length
+     * @param int $length
+     * @return bool
+     */
+    public function setLength($length) {}
+    
+    /**
+     * Get salt
+     * @return string
+     */
+    public function getSalt() {}
+    
+    /**
+     * Set salt
+     * @param string $salt
+     * @return bool
+     */
+    public function setSalt($salt) {}
+    
+}
+
+/**
+ * Exception class for KDF errors
+ */
+class KDFException {
+    
+    /**
+     * The key lenght is too low
+     */
+    const KEY_LENGTH_LOW = 1;
+    
+    /**
+     * The key lenght is too high
+     */
+    const KEY_LENGTH_HIGH = 2;
+    
+    /**
+     * The salt is too long
+     */
+    const SALT_LENGTH_HIGH = 3;
+    
+    /**
+     * The password is too long
+     */
+    const PASSWORD_LENGTH_INVALID = 4;
+    
+    /**
+     * KDF derivation failed
+     */
+    const DERIVATION_FAILED = 5;
+    
+}
+
+/**
+ * Class providing PBKDF2 functionality
+ */
+class PBKDF2 extends KDF {
+    /**
+     * KDF constructor
+     * @param string $hashAlgorithm
+     * @param int $length
+     * @param string $salt
+     * @param int $iterations
+     */
+    public function __construct($hashAlgorithm, $length, $salt = NULL, $iterations = 1000) {}
+    
+    /**
+     * Deriver hash for password
+     * @param string $password
+     * @return string
+     */
+    public function derive($password) {}
+    
+    /**
+     * Get iterations
+     * @return int
+     */
+    public function getIterations() {}
+    
+    /**
+     * Set iterations
+     * @param int $iterations
+     * @return bool
+     */
+    public function setIterations($iterations) {}
+    
+    /**
+     * Get hash algorithm
+     * @return string
+     */
+    public function getHashAlgorithm() {}
+    
+    /**
+     * Set hash algorithm
+     * @param string $hashAlgorithm
+     * @return bool
+     */
+    public function setHashAlgorithm($hashAlgorithm) {}
+    
+}
+
+/**
+ * Exception class for PBKDF2 errors
+ */
+class PBKDF2Exception extends KDFException {
+    
+    /**
+     * Hash algorithm '%s' not found
+     */
+    const HASH_ALGORITHM_NOT_FOUND = 1;
+    
+    /**
+     * Iterations count is too high
+     */
+    const ITERATIONS_HIGH = 2;
+    
+}
+
+/**
+ * Class for base64 encoding and docoding
+ */
+class Base64 {
+    /**
+     * Encodes string $data to base64 encoding
+     * @param string $data
+     * @return string
+     */
+    public function encode($data) {}
+    
+    /**
+     * Decodes base64 string $data to raw encoding
+     * @param string $data
+     * @return string
+     */
+    public function decode($data) {}
+    
+    /**
+     * Base64 constructor
+     */
+    public function __construct() {}
+    
+    /**
+     * Encodes block of characters from $data and saves the reminder of the last block
+     * to the encoding context
+     * @param string $data
+     */
+    public function encodeUpdate($data) {}
+    
+    /**
+     * Encodes characters that left in the encoding context
+     */
+    public function encodeFinish() {}
+    
+    /**
+     * Decodes block of characters from $data and saves the reminder of the last block
+     * to the encoding context
+     * @param string $data
+     */
+    public function decodeUpdate($data) {}
+    
+    /**
+     * Decodes characters that left in the encoding context
+     */
+    public function decodeFinish() {}
+    
+}
+
+/**
+ * Exception class for base64 errors
+ */
+class Base64Exception extends \Exception {
+    
+    /**
+     * The object is already used for decoding
+     */
+    const ENCODE_UPDATE_FORBIDDEN = 1;
+    
+    /**
+     * The object has not been intialized for encoding
+     */
+    const ENCODE_FINISH_FORBIDDEN = 2;
+    
+    /**
+     * The object is already used for encoding
+     */
+    const DECODE_UPDATE_FORBIDDEN = 3;
+    
+    /**
+     * The object has not been intialized for decoding
+     */
+    const DECODE_FINISH_FORBIDDEN = 4;
+    
+    /**
+     * Base64 decoded string does not contain valid characters
+     */
+    const DECODE_UPDATE_FAILED = 5;
+    
+    /**
+     * Input data length can't exceed max integer length
+     */
+    const INPUT_DATA_LENGTH_HIGH = 6;
+    
+}
+
+/**
+ * Class for generating random numbers
+ */
+class Rand {
+    /**
+     * Generates pseudo random bytes
+     * @param int $num
+     * @param bool $must_be_strong
+     * @param bool $returned_strong_result
+     * @return string
+     */
+    public static function generate($num, $must_be_strong = true, &$returned_strong_result = true) {}
+    
+    /**
+     * Mixes bytes in $buf into PRNG state
+     * @param string $buf
+     * @param float $entropy
+     * @return null
+     */
+    public static function seed($buf, $entropy = (float) strlen($buf)) {}
+    
+    /**
+     * Cleans up PRNG state
+     * @return null
+     */
+    public static function cleanup() {}
+    
+    /**
+     * Reads a number of bytes from file $filename and adds them to the PRNG. If
+     * max_bytes is non-negative, up to to max_bytes are read; if $max_bytes is
+     * negative, the complete file is read
+     * @param string $filename
+     * @param int $max_bytes
+     * @return int
+     */
+    public static function loadFile($filename, $max_bytes = -1) {}
+    
+    /**
+     * Writes a number of random bytes (currently 1024) to file $filename which can be
+     * used to initializethe PRNG by calling Crypto\Rand::loadFile() in a later session
+     * @param string $filename
+     * @return int
+     */
+    public static function writeFile($filename) {}
+    
+}
+
+/**
+ * Exception class for rand errors
+ */
+class RandException extends \Exception {
+    
+    /**
+     * The PRNG state is not yet unpredictable
+     */
+    const GENERATE_PREDICTABLE = 1;
+    
+    /**
+     * The bytes written were generated without appropriate seed
+     */
+    const FILE_WRITE_PREDICTABLE = 2;
+    
+    /**
+     * The requested number of bytes is too high
+     */
+    const REQUESTED_BYTES_NUMBER_TOO_HIGH = 3;
+    
+    /**
+     * The supplied seed length is too high
+     */
+    const SEED_LENGTH_TOO_HIGH = 4;
+    
+}
+}