Do a POW (Browser)

This commit is contained in:
Kagami Hiiragi 2015-01-09 16:12:23 +03:00
parent 9407e27529
commit 8c799f4e91
9 changed files with 200 additions and 21 deletions

1
.gitignore vendored
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@ -1,3 +1,4 @@
/node_modules/ /node_modules/
/npm-debug.log /npm-debug.log
/docs/ /docs/
/worker.browserify.js

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@ -1,4 +1,5 @@
node_modules /node_modules/
test* /test*
karma* /karma*
docs /docs/
/worker.browserify.js

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@ -1,5 +1,6 @@
.travis.yml /.travis.yml
.jshint* /.jshint*
karma* /karma*
docs /docs/
jsdoc.json /jsdoc.json
/worker.browserify.js

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@ -1,9 +1,11 @@
process.env.CHROME_BIN = "chromium-browser"; process.env.CHROME_BIN = "chromium-browser";
var allTests = !!process.env.ALL_TESTS; var allTests = !!process.env.ALL_TESTS;
var files = ["test.js"]; var files = ["test.js"];
// Kludgy way to pass a variable to `test.js`.
if (allTests) { if (allTests) {
// Kludgy way to pass a variable to `test.js`.
files.unshift("karma-all-tests.js"); files.unshift("karma-all-tests.js");
// Worker code.
files.push({pattern: "worker.browserify.js", included: false});
}; };
module.exports = function(config) { module.exports = function(config) {
@ -15,7 +17,7 @@ module.exports = function(config) {
// frameworks to use // frameworks to use
// available frameworks: https://npmjs.org/browse/keyword/karma-adapter // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
frameworks: ["mocha", "browserify"], frameworks: ["browserify", "mocha"],
// list of files / patterns to load in the browser // list of files / patterns to load in the browser
@ -73,6 +75,6 @@ module.exports = function(config) {
singleRun: true, singleRun: true,
browserNoActivityTimeout: allTests ? 60000 : 10000, browserNoActivityTimeout: allTests ? 120000 : 10000,
}); });
}; };

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@ -41,3 +41,82 @@ exports.getTarget = function(opts) {
assert(target <= 9007199254740991, "Unsafe target"); assert(target <= 9007199254740991, "Unsafe target");
return target; return target;
}; };
var FAILBACK_POOL_SIZE = 8;
// NOTE(Kagami): We don't use promise shim in Browser implementation
// because it's supported natively in new browsers (see
// <http://caniuse.com/#feat=promises>) and we can use only new browsers
// because of the WebCryptoAPI (see
// <http://caniuse.com/#feat=cryptography>).
exports.doPOW = function(opts) {
// Try to get native cores count then fallback to more or less
// reasonable value. See <https://stackoverflow.com/q/3289465> for
// details.
var poolSize = opts.poolSize || navigator.hardwareConcurrency;
poolSize = poolSize || FAILBACK_POOL_SIZE;
// Check all input params prematurely to not let promise executor or
// worker to fail because of it.
assert(poolSize > 0, "Bad pool size");
assert(opts.workerUrl, "Bad worker URL");
assert(typeof opts.target === "number", "Bad target");
assert(Buffer.isBuffer(opts.initialHash), "Bad initial hash");
var cancel;
var promise = new Promise(function(resolve, reject) {
function terminateAll() {
while (workers.length) {
workers.shift().terminate();
}
}
function onmessage(e) {
terminateAll();
if (e.data >= 0) {
resolve(e.data);
} else {
// It's very unlikely that execution will ever reach this place.
// Currently the only reason why Worker may return value less
// than zero is a 32-bit nonce overflow (see worker
// implementation). It's more than 4G double hashes.
reject();
}
}
function onerror(e) {
// XXX(Kagami): `onerror` events fires in Chrome even after all
// workers were terminated. It doesn't cause wrong behaviour but
// beware that this function may be executed several times.
terminateAll();
reject(e);
}
var workers = [];
var worker;
for (var i = 0; i < poolSize; i++) {
worker = new Worker(opts.workerUrl);
workers.push(worker);
// NOTE(Kagami): There is no race condition here. `onmessage` can
// only be called _after_ this for-loop finishes. See
// <https://stackoverflow.com/a/18192122> for details.
worker.onmessage = onmessage;
worker.onerror = onerror;
worker.postMessage({
num: i,
poolSize: poolSize,
target: opts.target,
initialHash: opts.initialHash,
});
}
cancel = function(e) {
terminateAll();
reject(e);
};
});
// Allow to stop POW via custom function added to the Promise
// instance.
promise.cancel = cancel;
return promise;
};

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@ -3,9 +3,11 @@
* @see {@link https://bitmessage.org/wiki/Proof_of_work} * @see {@link https://bitmessage.org/wiki/Proof_of_work}
* @module bitmessage/pow * @module bitmessage/pow
*/ */
// TODO(Kagami): Find a way how to document object params properly.
"use strict"; "use strict";
var objectAssign = Object.assign || require("object-assign");
var bmcrypto = require("./crypto"); var bmcrypto = require("./crypto");
var platform = require("./platform"); var platform = require("./platform");
@ -17,7 +19,6 @@ var DEFAULT_EXTRA_BYTES = 1000;
* @param {Object} opts - Target options * @param {Object} opts - Target options
* @return {number} Target. * @return {number} Target.
*/ */
// TODO(Kagami): Find a way how to document object params properly.
// Just a wrapper around platform-specific implementation. // Just a wrapper around platform-specific implementation.
exports.getTarget = function(opts) { exports.getTarget = function(opts) {
var payloadLength = opts.payloadLength || opts.payload.length; var payloadLength = opts.payloadLength || opts.payload.length;
@ -75,3 +76,20 @@ exports.check = function(opts) {
return trialLo <= targetLo; return trialLo <= targetLo;
} }
}; };
/**
* Do a POW.
* @param {Object} opts - Proof of work options
* @return {Promise.<Buffer>} A promise that contains computed nonce for
* the given target when fulfilled.
*/
exports.do = function(opts) {
var initialHash;
if (opts.payload) {
initialHash = bmcrypto.sha512(opts.payload);
} else {
initialHash = opts.initialHash;
}
opts = objectAssign({}, opts, {initialHash: initialHash});
return platform.doPOW(opts);
};

65
lib/worker.browser.js Normal file
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@ -0,0 +1,65 @@
/**
* Web Worker routines for Browser platform.
*/
"use strict";
// NOTE(Kagami): In order to use it you need to create separate
// browserify bundle for this file, place it somewhere in your HTTP
// server assets path (under the same origin with your application code)
// and then pass appropriate `workerUrl` value to the function that
// spawns workers.
// You may also try to pass object URL instead. See
// <http://mdn.io/worker.worker>, <https://stackoverflow.com/q/10343913>
// for details.
// XXX(Kagami): This is rather unpleasent that we use different SHA-2
// implementations for main library code and for worker code (we use
// `sha.js` here because it's faster). Though worker code lays in
// separate file so it shouldn't result in any download overhead.
var createHash = require("sha.js");
function sha512(buf) {
return createHash("sha512").update(buf).digest();
}
function pow(opts) {
var nonce = opts.num;
var poolSize = opts.poolSize;
var message = new Buffer(72);
message.fill(0);
Buffer(opts.initialHash).copy(message, 8);
var targetHi = Math.floor(opts.target / 4294967296);
var targetLo = opts.target % 4294967296;
var digest, trialHi, trialLo;
while (true) {
// uint32_t overflow. There is no much need to fix it since 4G
// double hashes would we computed too long anyway in a Browser.
if (nonce > 4294967295) {
return -1;
}
message.writeUInt32BE(nonce, 4, true);
digest = sha512(sha512(message));
trialHi = digest.readUInt32BE(0, true);
if (trialHi > targetHi) {
nonce += poolSize;
} else if (trialHi === targetHi) {
trialLo = digest.readUInt32BE(4, true);
if (trialLo > targetLo) {
nonce += poolSize;
} else {
return nonce;
}
} else {
return nonce;
}
}
}
onmessage = function(e) { // jshint ignore:line
var nonce = pow(e.data);
postMessage(nonce); // jshint ignore:line
};

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@ -7,11 +7,12 @@
"./lib/platform.js": "./lib/platform.browser.js" "./lib/platform.js": "./lib/platform.browser.js"
}, },
"scripts": { "scripts": {
"test": "ALL_TESTS=1 mocha && ALL_TESTS=1 xvfb-run -a karma start && jshint .", "test": "ALL_TESTS=1 mocha && ALL_TESTS=1 npm run -s kc && ALL_TESTS=1 npm run -s kf && jshint .",
"m": "mocha", "m": "mocha",
"k": "xvfb-run -a karma start", "k": "npm run -s w && xvfb-run -a karma start",
"kc": "xvfb-run -a karma start --browsers Chromium", "kc": "npm run -s w && xvfb-run -a karma start --browsers Chromium",
"kf": "xvfb-run -a karma start --browsers Firefox", "kf": "npm run -s w && xvfb-run -a karma start --browsers Firefox",
"w": "browserify lib/worker.browser.js > worker.browserify.js",
"j": "jshint .", "j": "jshint .",
"d": "jsdoc -c jsdoc.json", "d": "jsdoc -c jsdoc.json",
"mv-docs": "rm -rf docs && jsdoc -c jsdoc.json && D=`mktemp -d` && mv docs \"$D\" && git checkout gh-pages && rm -rf docs && mv \"$D/docs\" . && rm -rf \"$D\"" "mv-docs": "rm -rf docs && jsdoc -c jsdoc.json && D=`mktemp -d` && mv docs \"$D\" && git checkout gh-pages && rm -rf docs && mv \"$D/docs\" . && rm -rf \"$D\""
@ -33,14 +34,15 @@
}, },
"homepage": "https://github.com/bitchan/bitmessage", "homepage": "https://github.com/bitchan/bitmessage",
"devDependencies": { "devDependencies": {
"browserify": "^8.1.0",
"chai": "*", "chai": "*",
"jsdoc": "^3.3.0-alpha13", "jsdoc": "^3.3.0-alpha13",
"jshint": "*", "jshint": "*",
"karma": "^0.12.28", "karma": "^0.12.31",
"karma-browserify": "^1.0.1", "karma-browserify": "^2.0.0",
"karma-chrome-launcher": "^0.1.7", "karma-chrome-launcher": "^0.1.7",
"karma-cli": "~0.0.4", "karma-cli": "~0.0.4",
"karma-firefox-launcher": "^0.1.3", "karma-firefox-launcher": "^0.1.4",
"karma-mocha": "^0.1.10", "karma-mocha": "^0.1.10",
"karma-mocha-reporter": "^0.3.1", "karma-mocha-reporter": "^0.3.1",
"mocha": "*" "mocha": "*"

12
test.js
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@ -278,6 +278,16 @@ describe("POW", function() {
expect(POW.check({nonce: 3122437, target: 4864647698763, initialHash: Buffer("8ff2d685db89a0af2e3dbfd3f700ae96ef4d9a1eac72fd778bbb368c7510cddda349e03207e1c4965bd95c6f7265e8f1a481a08afab3874eaafb9ade09a10880", "hex")})).to.be.true; expect(POW.check({nonce: 3122437, target: 4864647698763, initialHash: Buffer("8ff2d685db89a0af2e3dbfd3f700ae96ef4d9a1eac72fd778bbb368c7510cddda349e03207e1c4965bd95c6f7265e8f1a481a08afab3874eaafb9ade09a10880", "hex")})).to.be.true;
expect(POW.check({nonce: 3122436, target: 4864647698763, initialHash: Buffer("8ff2d685db89a0af2e3dbfd3f700ae96ef4d9a1eac72fd778bbb368c7510cddda349e03207e1c4965bd95c6f7265e8f1a481a08afab3874eaafb9ade09a10880", "hex")})).to.be.false; expect(POW.check({nonce: 3122436, target: 4864647698763, initialHash: Buffer("8ff2d685db89a0af2e3dbfd3f700ae96ef4d9a1eac72fd778bbb368c7510cddda349e03207e1c4965bd95c6f7265e8f1a481a08afab3874eaafb9ade09a10880", "hex")})).to.be.false;
}); });
if (allTests && typeof window !== "undefined") {
it("should do a POW", function() {
this.timeout(120000);
return POW.do({workerUrl: "/base/worker.browserify.js", target: 10693764680411, initialHash: Buffer("8ff2d685db89a0af2e3dbfd3f700ae96ef4d9a1eac72fd778bbb368c7510cddda349e03207e1c4965bd95c6f7265e8f1a481a08afab3874eaafb9ade09a10880", "hex")})
.then(function(nonce) {
expect(nonce).to.equal(2373146);
});
});
}
}); });
describe("High-level classes", function() { describe("High-level classes", function() {
@ -317,7 +327,7 @@ describe("High-level classes", function() {
// very slow. This need to be fixed. // very slow. This need to be fixed.
if (allTests && typeof window === "undefined") { if (allTests && typeof window === "undefined") {
it("should allow to generate shorter address", function() { it("should allow to generate shorter address", function() {
this.timeout(60000); this.timeout(120000);
var addr = Address.fromRandom({ripelen: 18}); var addr = Address.fromRandom({ripelen: 18});
var ripe = addr.getRipe({short: true}); var ripe = addr.getRipe({short: true});
expect(ripe.length).to.be.at.most(18); expect(ripe.length).to.be.at.most(18);