feat: add sha3 hash

std/hash/_sha3/keccak.ts

@@ -0,0 +1,52 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+import { Sponge } from "./Sponge.ts";
+import { keccakf } from "./keccakf.ts";
+
+/** Keccak-224 hash */
+export class Keccak224 extends Sponge {
+  constructor() {
+    super({
+      bitsize: 224,
+      rate: 144,
+      dsbyte: 1,
+      permutator: keccakf,
+    });
+  }
+}
+
+/** Keccak-256 hash */
+export class Keccak256 extends Sponge {
+  constructor() {
+    super({
+      bitsize: 256,
+      rate: 136,
+      dsbyte: 1,
+      permutator: keccakf,
+    });
+  }
+}
+
+/** Keccak-384 hash */
+export class Keccak384 extends Sponge {
+  constructor() {
+    super({
+      bitsize: 384,
+      rate: 104,
+      dsbyte: 1,
+      permutator: keccakf,
+    });
+  }
+}
+
+/** Keccak-512 hash */
+export class Keccak512 extends Sponge {
+  constructor() {
+    super({
+      bitsize: 512,
+      rate: 72,
+      dsbyte: 1,
+      permutator: keccakf,
+    });
+  }
+}