1 files changed, 50 insertions, 0 deletions
diff --git a/extensions/crypto/01_crypto.js b/extensions/crypto/01_crypto.js
new file mode 100644
index 000000000..dba6b0091
--- /dev/null
+++ b/extensions/crypto/01_crypto.js
@@ -0,0 +1,50 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+"use strict";
+
+((window) => {
+  const core = window.Deno.core;
+
+  function getRandomValues(arrayBufferView) {
+    if (!ArrayBuffer.isView(arrayBufferView)) {
+      throw new TypeError(
+        "Argument 1 does not implement interface ArrayBufferView",
+      );
+    }
+    if (
+      !(
+        arrayBufferView instanceof Int8Array ||
+        arrayBufferView instanceof Uint8Array ||
+        arrayBufferView instanceof Int16Array ||
+        arrayBufferView instanceof Uint16Array ||
+        arrayBufferView instanceof Int32Array ||
+        arrayBufferView instanceof Uint32Array ||
+        arrayBufferView instanceof Uint8ClampedArray
+      )
+    ) {
+      throw new DOMException(
+        "The provided ArrayBufferView is not an integer array type",
+        "TypeMismatchError",
+      );
+    }
+    if (arrayBufferView.byteLength > 65536) {
+      throw new DOMException(
+        `The ArrayBufferView's byte length (${arrayBufferView.byteLength}) exceeds the number of bytes of entropy available via this API (65536)`,
+        "QuotaExceededError",
+      );
+    }
+    const ui8 = new Uint8Array(
+      arrayBufferView.buffer,
+      arrayBufferView.byteOffset,
+      arrayBufferView.byteLength,
+    );
+    core.opSync("op_crypto_get_random_values", null, ui8);
+    return arrayBufferView;
+  }
+
+  window.crypto = {
+    getRandomValues,
+  };
+  window.__bootstrap.crypto = {
+    getRandomValues,
+  };
+})(this);