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-rw-r--r--vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Reader/Xls/RC4.php61
1 files changed, 61 insertions, 0 deletions
diff --git a/vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Reader/Xls/RC4.php b/vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Reader/Xls/RC4.php
new file mode 100644
index 0000000..af17f12
--- /dev/null
+++ b/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;
+ }
+}