MWCryptHash.php

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<?php
class MWCryptHash {
    protected static $algo = null;
 
    protected static $hashLength = [
        'binary' => null,
        'hex' => null,
    ];
 
    public static function hashAlgo() {
        if ( self::$algo !== null ) {
            return self::$algo;
        }
 
        $algos = hash_hmac_algos();
        $preference = [ 'whirlpool', 'sha256' ];
 
        foreach ( $preference as $algorithm ) {
            if ( in_array( $algorithm, $algos, true ) ) {
                self::$algo = $algorithm;
                return self::$algo;
            }
        }
 
        throw new DomainException( 'Could not find an acceptable hashing function.' );
    }
 
    public static function hashLength( $raw = true ) {
        $key = $raw ? 'binary' : 'hex';
        if ( self::$hashLength[$key] === null ) {
            self::$hashLength[$key] = strlen( self::hash( '', $raw ) );
        }
 
        // @phan-suppress-next-line PhanTypeMismatchReturnNullable False positive
        return self::$hashLength[$key];
    }
 
    public static function hash( $data, $raw = true ) {
        return hash( self::hashAlgo(), $data, $raw );
    }
 
    public static function hmac( $data, $key, $raw = true ) {
        if ( !is_string( $key ) ) {
            // hash_hmac tolerates non-string (would return null with warning)
            throw new InvalidArgumentException( 'Invalid key type: ' . gettype( $key ) );
        }
        return hash_hmac( self::hashAlgo(), $data, $key, $raw );
    }
 
}