updated-packages

vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Reader/Xls/RC4.php

@@ -0,0 +1,61 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Reader\Xls;
+
+class RC4
+{
+    // Context
+    protected $s = [];
+
+    protected $i = 0;
+
+    protected $j = 0;
+
+    /**
+     * RC4 stream decryption/encryption constrcutor.
+     *
+     * @param string $key Encryption key/passphrase
+     */
+    public function __construct($key)
+    {
+        $len = strlen($key);
+
+        for ($this->i = 0; $this->i < 256; ++$this->i) {
+            $this->s[$this->i] = $this->i;
+        }
+
+        $this->j = 0;
+        for ($this->i = 0; $this->i < 256; ++$this->i) {
+            $this->j = ($this->j + $this->s[$this->i] + ord($key[$this->i % $len])) % 256;
+            $t = $this->s[$this->i];
+            $this->s[$this->i] = $this->s[$this->j];
+            $this->s[$this->j] = $t;
+        }
+        $this->i = $this->j = 0;
+    }
+
+    /**
+     * Symmetric decryption/encryption function.
+     *
+     * @param string $data Data to encrypt/decrypt
+     *
+     * @return string
+     */
+    public function RC4($data)
+    {
+        $len = strlen($data);
+        for ($c = 0; $c < $len; ++$c) {
+            $this->i = ($this->i + 1) % 256;
+            $this->j = ($this->j + $this->s[$this->i]) % 256;
+            $t = $this->s[$this->i];
+            $this->s[$this->i] = $this->s[$this->j];
+            $this->s[$this->j] = $t;
+
+            $t = ($this->s[$this->i] + $this->s[$this->j]) % 256;
+
+            $data[$c] = chr(ord($data[$c]) ^ $this->s[$t]);
+        }
+
+        return $data;
+    }
+}