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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// Copyright 2014-2017 browserify-aes contributors. All rights reserved. MIT license.// Copyright 2013 Maxwell Krohn. All rights reserved. MIT license.// Copyright 2009-2013 Jeff Mott. All rights reserved. MIT license.// Copyright 2009-2015, Emily Stark, Mike Hamburg and Dan Boneh at Stanford University. All rights reserved.
// deno-lint-ignore-file no-var
import { Buffer } from "../../../buffer.ts";
var ZEROES = Buffer.alloc(16, 0);
function toArray(buf) { return [ buf.readUInt32BE(0), buf.readUInt32BE(4), buf.readUInt32BE(8), buf.readUInt32BE(12), ];}
function fromArray(out) { var buf = Buffer.allocUnsafe(16); buf.writeUInt32BE(out[0] >>> 0, 0); buf.writeUInt32BE(out[1] >>> 0, 4); buf.writeUInt32BE(out[2] >>> 0, 8); buf.writeUInt32BE(out[3] >>> 0, 12); return buf;}
export function GHASH(key) { this.h = key; this.state = Buffer.alloc(16, 0); this.cache = Buffer.allocUnsafe(0);}
// from http://bitwiseshiftleft.github.io/sjcl/doc/symbols/src/core_gcm.js.html// by Juho Vähä-HerttuaGHASH.prototype.ghash = function (block) { var i = -1; while (++i < block.length) { this.state[i] ^= block[i]; } this._multiply();};
GHASH.prototype._multiply = function () { var Vi = toArray(this.h); var Zi = [0, 0, 0, 0]; var j, xi, lsbVi; var i = -1; while (++i < 128) { xi = (this.state[~~(i / 8)] & (1 << (7 - (i % 8)))) !== 0; if (xi) { // Z_i+1 = Z_i ^ V_i Zi[0] ^= Vi[0]; Zi[1] ^= Vi[1]; Zi[2] ^= Vi[2]; Zi[3] ^= Vi[3]; }
// Store the value of LSB(V_i) lsbVi = (Vi[3] & 1) !== 0;
// V_i+1 = V_i >> 1 for (j = 3; j > 0; j--) { Vi[j] = (Vi[j] >>> 1) | ((Vi[j - 1] & 1) << 31); } Vi[0] = Vi[0] >>> 1;
// If LSB(V_i) is 1, V_i+1 = (V_i >> 1) ^ R if (lsbVi) { Vi[0] = Vi[0] ^ (0xe1 << 24); } } this.state = fromArray(Zi);};
GHASH.prototype.update = function (buf) { this.cache = Buffer.concat([this.cache, buf]); var chunk; while (this.cache.length >= 16) { chunk = this.cache.slice(0, 16); this.cache = this.cache.slice(16); this.ghash(chunk); }};
GHASH.prototype.final = function (abl, bl) { if (this.cache.length) { this.ghash(Buffer.concat([this.cache, ZEROES], 16)); }
this.ghash(fromArray([0, abl, 0, bl])); return this.state;};