1 files changed, 119 insertions, 0 deletions
diff --git a/vendor/paragonie/sodium_compat/src/Core/ChaCha20/Ctx.php b/vendor/paragonie/sodium_compat/src/Core/ChaCha20/Ctx.php
new file mode 100644
index 0000000..47a42b7
--- /dev/null
+++ b/vendor/paragonie/sodium_compat/src/Core/ChaCha20/Ctx.php
@@ -0,0 +1,119 @@
+<?php
+
+if (class_exists('ParagonIE_Sodium_Core_ChaCha20_Ctx', false)) {
+    return;
+}
+
+/**
+ * Class ParagonIE_Sodium_Core_ChaCha20_Ctx
+ */
+class ParagonIE_Sodium_Core_ChaCha20_Ctx extends ParagonIE_Sodium_Core_Util implements ArrayAccess
+{
+    /**
+     * @var SplFixedArray internally, <int, int>
+     */
+    protected $container;
+
+    /**
+     * ParagonIE_Sodium_Core_ChaCha20_Ctx constructor.
+     *
+     * @internal You should not use this directly from another application
+     *
+     * @param string $key     ChaCha20 key.
+     * @param string $iv      Initialization Vector (a.k.a. nonce).
+     * @param string $counter The initial counter value.
+     *                        Defaults to 8 0x00 bytes.
+     * @throws InvalidArgumentException
+     * @throws TypeError
+     */
+    public function __construct($key = '', $iv = '', $counter = '')
+    {
+        if (self::strlen($key) !== 32) {
+            throw new InvalidArgumentException('ChaCha20 expects a 256-bit key.');
+        }
+        if (self::strlen($iv) !== 8) {
+            throw new InvalidArgumentException('ChaCha20 expects a 64-bit nonce.');
+        }
+        $this->container = new SplFixedArray(16);
+
+        /* "expand 32-byte k" as per ChaCha20 spec */
+        $this->container[0]  = 0x61707865;
+        $this->container[1]  = 0x3320646e;
+        $this->container[2]  = 0x79622d32;
+        $this->container[3]  = 0x6b206574;
+        $this->container[4]  = self::load_4(self::substr($key, 0, 4));
+        $this->container[5]  = self::load_4(self::substr($key, 4, 4));
+        $this->container[6]  = self::load_4(self::substr($key, 8, 4));
+        $this->container[7]  = self::load_4(self::substr($key, 12, 4));
+        $this->container[8]  = self::load_4(self::substr($key, 16, 4));
+        $this->container[9]  = self::load_4(self::substr($key, 20, 4));
+        $this->container[10] = self::load_4(self::substr($key, 24, 4));
+        $this->container[11] = self::load_4(self::substr($key, 28, 4));
+
+        if (empty($counter)) {
+            $this->container[12] = 0;
+            $this->container[13] = 0;
+        } else {
+            $this->container[12] = self::load_4(self::substr($counter, 0, 4));
+            $this->container[13] = self::load_4(self::substr($counter, 4, 4));
+        }
+        $this->container[14] = self::load_4(self::substr($iv, 0, 4));
+        $this->container[15] = self::load_4(self::substr($iv, 4, 4));
+    }
+
+    /**
+     * @internal You should not use this directly from another application
+     *
+     * @param int $offset
+     * @param int $value
+     * @return void
+     * @psalm-suppress MixedArrayOffset
+     */
+    public function offsetSet($offset, $value)
+    {
+        if (!is_int($offset)) {
+            throw new InvalidArgumentException('Expected an integer');
+        }
+        if (!is_int($value)) {
+            throw new InvalidArgumentException('Expected an integer');
+        }
+        $this->container[$offset] = $value;
+    }
+
+    /**
+     * @internal You should not use this directly from another application
+     *
+     * @param int $offset
+     * @return bool
+     */
+    public function offsetExists($offset)
+    {
+        return isset($this->container[$offset]);
+    }
+
+    /**
+     * @internal You should not use this directly from another application
+     *
+     * @param int $offset
+     * @return void
+     * @psalm-suppress MixedArrayOffset
+     */
+    public function offsetUnset($offset)
+    {
+        unset($this->container[$offset]);
+    }
+
+    /**
+     * @internal You should not use this directly from another application
+     *
+     * @param int $offset
+     * @return mixed|null
+     * @psalm-suppress MixedArrayOffset
+     */
+    public function offsetGet($offset)
+    {
+        return isset($this->container[$offset])
+            ? $this->container[$offset]
+            : null;
+    }
+}