feat(std/hash): add sha3 (#5558)

1 files changed, 51 insertions, 0 deletions

diff --git a/std/hash/_sha3/shake.ts b/std/hash/_sha3/shake.ts
new file mode 100644
index 000000000..05c699ea5
--- /dev/null
+++ b/std/hash/_sha3/shake.ts
@@ -0,0 +1,51 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+import { Sponge } from "./sponge.ts";
+import { keccakf } from "./keccakf.ts";
+
+/** Shake128 hash */
+export class Shake128 extends Sponge {
+  /**
+   * Instantiates a new Shake128 hash
+   * @param bitsize length of hash in bits
+   */
+  constructor(bitsize: number) {
+    if (bitsize < 8) {
+      throw new Error("shake128: `bitsize` too small");
+    }
+
+    if (bitsize % 8 !== 0) {
+      throw new Error("shake128: `bitsize` must be multiple of 8");
+    }
+
+    super({
+      bitsize: bitsize,
+      rate: 168,
+      dsbyte: 0x1f,
+      permutator: keccakf,
+    });
+  }
+}
+
+/**
+ * Instantiates a new Shake256 hash
+ * @param bitsize length of hash in bits
+ */
+export class Shake256 extends Sponge {
+  constructor(bitsize: number) {
+    if (bitsize < 8) {
+      throw new Error("shake256: `bitsize` too small");
+    }
+
+    if (bitsize % 8 !== 0) {
+      throw new Error("shake256: `bitsize` must be multiple of 8");
+    }
+
+    super({
+      bitsize: bitsize,
+      rate: 136,
+      dsbyte: 0x1f,
+      permutator: keccakf,
+    });
+  }
+}