oauth3.js/oauth3.crypto.js

296 lines
11 KiB
JavaScript

;(function (exports) {
'use strict';
var OAUTH3 = exports.OAUTH3 = exports.OAUTH3 || require('./oauth3.core.js').OAUTH3;
OAUTH3.crypto = {};
try {
OAUTH3.crypto.core = require('./oauth3.node.crypto');
} catch (error) {
OAUTH3.crypto.core = {};
OAUTH3.crypto.core.ready = false;
var finishBeforeReady = [];
var deferedCalls = [];
// We don't currently have a fallback method for this function, so we assign
// it directly to the core object instead of the webCrypto object.
OAUTH3.crypto.core.randomBytes = function (size) {
var buf = OAUTH3._browser.window.crypto.getRandomValues(new Uint8Array(size));
return OAUTH3.PromiseA.resolve(buf);
};
var webCrypto = {};
var deferCryptoCall = function(name) {
return function() {
var args = arguments;
return new OAUTH3.PromiseA(function(resolve, reject) {
deferedCalls.push(function(){
try {
webCrypto[name].apply(webCrypto, args)
.then(function(result){
resolve(result);
});
} catch(e) {
reject(e);
}
});
});
};
};
OAUTH3.crypto.core.sha256 = deferCryptoCall("sha256");
webCrypto.sha256 = function (buf) {
return OAUTH3._browser.window.crypto.subtle.digest({name: 'SHA-256'}, buf);
};
OAUTH3.crypto.core.pbkdf2 = deferCryptoCall("pbkdf2");
webCrypto.pbkdf2 = function (password, salt) {
return OAUTH3._browser.window.crypto.subtle.importKey('raw', OAUTH3._binStr.binStrToBuffer(password), {name: 'PBKDF2'}, false, ['deriveKey'])
.then(function (key) {
var opts = {name: 'PBKDF2', salt: salt, iterations: 8192, hash: {name: 'SHA-256'}};
return OAUTH3._browser.window.crypto.subtle.deriveKey(opts, key, {name: 'AES-GCM', length: 128}, true, ['encrypt', 'decrypt']);
})
.then(function (key) {
return OAUTH3._browser.window.crypto.subtle.exportKey('raw', key);
});
};
OAUTH3.crypto.core.encrypt = deferCryptoCall("encrypt");
webCrypto.encrypt = function (rawKey, iv, data) {
return OAUTH3._browser.window.crypto.subtle.importKey('raw', rawKey, {name: 'AES-GCM'}, false, ['encrypt'])
.then(function (key) {
return OAUTH3._browser.window.crypto.subtle.encrypt({name: 'AES-GCM', iv: iv}, key, data);
});
};
OAUTH3.crypto.core.decrypt = deferCryptoCall("decrypt");
webCrypto.decrypt = function (rawKey, iv, data) {
return OAUTH3._browser.window.crypto.subtle.importKey('raw', rawKey, {name: 'AES-GCM'}, false, ['decrypt'])
.then(function (key) {
return OAUTH3._browser.window.crypto.subtle.decrypt({name: 'AES-GCM', iv: iv}, key, data);
});
};
OAUTH3.crypto.core.genEcdsaKeyPair = deferCryptoCall("genEcdsaKeyPair");
webCrypto.genEcdsaKeyPair = function () {
return OAUTH3._browser.window.crypto.subtle.generateKey({name: 'ECDSA', namedCurve: 'P-256'}, true, ['sign', 'verify'])
.then(function (keyPair) {
return OAUTH3.PromiseA.all([
OAUTH3._browser.window.crypto.subtle.exportKey('jwk', keyPair.privateKey)
, OAUTH3._browser.window.crypto.subtle.exportKey('jwk', keyPair.publicKey)
]);
}).then(function (jwkPair) {
return { privateKey: jwkPair[0], publicKey: jwkPair[1] };
});
};
OAUTH3.crypto.core.sign = deferCryptoCall("sign");
webCrypto.sign = function (jwk, msg) {
return OAUTH3._browser.window.crypto.subtle.importKey('jwk', jwk, {name: 'ECDSA', namedCurve: jwk.crv}, false, ['sign'])
.then(function (key) {
return OAUTH3._browser.window.crypto.subtle.sign({name: 'ECDSA', hash: {name: 'SHA-256'}}, key, msg);
})
.then(function (sig) {
return new Uint8Array(sig);
});
};
OAUTH3.crypto.core.verify = deferCryptoCall("verify");
webCrypto.verify = function (jwk, msg, signature) {
// If the JWK has properties that should only exist on the private key or is missing
// "verify" in the key_ops, importing in as a public key won't work.
if (jwk.hasOwnProperty('d') || jwk.hasOwnProperty('key_ops')) {
jwk = JSON.parse(JSON.stringify(jwk));
delete jwk.d;
delete jwk.key_ops;
}
return OAUTH3._browser.window.crypto.subtle.importKey('jwk', jwk, {name: 'ECDSA', namedCurve: jwk.crv}, false, ['verify'])
.then(function (key) {
return OAUTH3._browser.window.crypto.subtle.verify({name: 'ECDSA', hash: {name: 'SHA-256'}}, key, signature, msg);
});
};
function checkWebCrypto() {
/* global OAUTH3_crypto_fallback */
var loadFallback = function() {
var prom;
loadFallback = function () { return prom; };
prom = new OAUTH3.PromiseA(function (resolve) {
var body = document.getElementsByTagName('body')[0];
var script = document.createElement('script');
script.type = 'text/javascript';
script.onload = resolve;
script.onreadystatechange = function () {
if (this.readyState === 'complete' || this.readyState === 'loaded') {
resolve();
}
};
script.src = '/assets/oauth3.org/oauth3.crypto.fallback.js';
body.appendChild(script);
});
return prom;
};
function checkException(name, func) {
return OAUTH3.PromiseA.resolve().then(func)
.then(function () {
OAUTH3.crypto.core[name] = webCrypto[name];
}, function (err) {
console.warn('error with WebCrypto', name, '- using fallback', err);
return loadFallback().then(function () {
OAUTH3.crypto.core[name] = OAUTH3_crypto_fallback[name];
});
});
}
function checkResult(name, expected, func) {
finishBeforeReady.push(checkException(name, function () {
return func()
.then(function (result) {
if (typeof expected === typeof result) {
return result;
}
return OAUTH3._base64.bufferToUrlSafe(result);
})
.then(function (result) {
if (result !== expected) {
throw new Error("result ("+result+") doesn't match expectation ("+expected+")");
}
});
}));
}
var zeroBuf = new Uint8Array([0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]);
var dataBuf = OAUTH3._base64.urlSafeToBuffer('1234567890abcdefghijklmn');
var keyBuf = OAUTH3._base64.urlSafeToBuffer('l_Aeoqk6ePjwjCYrlHrgrg');
var encBuf = OAUTH3._base64.urlSafeToBuffer('Ji_gEtcNElUONSR4Mf9S75davXjh_6-oQN9AgO5UF8rERw');
checkResult('sha256', 'BwMveUm2V1axuERvUoxM4dScgNl9yKhER9a6p80GXj4', function () {
return webCrypto.sha256(dataBuf);
});
checkResult('pbkdf2', OAUTH3._base64.bufferToUrlSafe(keyBuf), function () {
return webCrypto.pbkdf2('password', zeroBuf);
});
checkResult('encrypt', OAUTH3._base64.bufferToUrlSafe(encBuf), function () {
return webCrypto.encrypt(keyBuf, zeroBuf.slice(0, 12), dataBuf);
});
checkResult('decrypt', OAUTH3._base64.bufferToUrlSafe(dataBuf), function () {
return webCrypto.decrypt(keyBuf, zeroBuf.slice(0, 12), encBuf);
});
var jwk = {
kty: "EC"
, crv: "P-256"
, d: "ChXx7ea5YtEltCufA8CVb0lQv3glcCfcSpEgdedgIP0"
, x: "Akt5ZDbytcKS5UQMURvGb_UIMS4qFctDwrX8bX22ato"
, y: "cV7nhpWNT1FeRIbdold4jLtgsEpZBFcNy3p2E5mqvto"
};
var sig = OAUTH3._base64.urlSafeToBuffer('nc3F8qeP8OXpfqPD9tTcFQg0Wfp37RTAppLPIKE1ZupR_8Aba64hNExwd1dOk802OFQxaECPDZCkKe7WA9RXAg');
checkResult('verify', true, function() {
return webCrypto.verify(jwk, dataBuf, sig);
});
// The results of these functions are less predictable, so we can't check their return value.
finishBeforeReady.push(checkException('genEcdsaKeyPair', function () {
return webCrypto.genEcdsaKeyPair();
}));
finishBeforeReady.push(checkException('sign', function () {
return webCrypto.sign(jwk, dataBuf);
}));
OAUTH3.PromiseA.all(finishBeforeReady)
.then(function(results) {
OAUTH3.crypto.core.ready = true;
deferedCalls.forEach(function(request) {
request();
});
});
}
checkWebCrypto();
}
OAUTH3.crypto.thumbprintJwk = function (jwk) {
var keys;
if (jwk.kty === 'EC') {
keys = ['crv', 'x', 'y'];
} else if (jwk.kty === 'RSA') {
keys = ['e', 'n'];
} else if (jwk.kty === 'oct') {
keys = ['k'];
} else {
return OAUTH3.PromiseA.reject(new Error('invalid JWK key type ' + jwk.kty));
}
keys.push('kty');
keys.sort();
var missing = keys.filter(function (name) { return !jwk.hasOwnProperty(name); });
if (missing.length > 0) {
return OAUTH3.PromiseA.reject(new Error('JWK of type '+jwk.kty+' missing fields ' + missing));
}
// I'm not actually 100% sure this behavior is guaranteed, but when we use an array as the
// replacer argument the keys are always in the order they appeared in the array.
var jwkStr = JSON.stringify(jwk, keys);
return OAUTH3.crypto.core.sha256(OAUTH3._binStr.binStrToBuffer(jwkStr))
.then(OAUTH3._base64.bufferToUrlSafe);
};
OAUTH3.crypto.createKeyPair = function () {
// TODO: maybe support other types of key pairs, not just ECDSA P-256
return OAUTH3.crypto.core.genEcdsaKeyPair().then(function (keyPair) {
return OAUTH3.crypto.thumbprintJwk(keyPair.publicKey).then(function (kid) {
keyPair.privateKey.alg = keyPair.publicKey.alg = 'ES256';
keyPair.privateKey.kid = keyPair.publicKey.kid = kid;
return keyPair;
});
});
};
OAUTH3.crypto.encryptKeyPair = function (keyPair, password) {
var saltProm = OAUTH3.crypto.core.randomBytes(16);
var kekProm = saltProm.then(function (salt) {
return OAUTH3.crypto.core.pbkdf2(password, salt);
});
return OAUTH3.PromiseA.all([
kekProm
, saltProm
, OAUTH3.crypto.core.randomBytes(12)
, ]).then(function (results) {
var kek = results[0];
var salt = results[1];
var ecdsaIv = results[2];
var privKeyBuf = OAUTH3._binStr.binStrToBuffer(JSON.stringify(keyPair.privateKey));
return OAUTH3.crypto.core.encrypt(kek, ecdsaIv, privKeyBuf).then(function (encrypted) {
return {
publicKey: keyPair.publicKey
, privateKey: OAUTH3._base64.bufferToUrlSafe(encrypted)
, salt: OAUTH3._base64.bufferToUrlSafe(salt)
, ecdsaIv: OAUTH3._base64.bufferToUrlSafe(ecdsaIv)
, };
});
});
};
OAUTH3.crypto.decryptKeyPair = function (storedObj, password) {
var salt = OAUTH3._base64.urlSafeToBuffer(storedObj.salt);
var encJwk = OAUTH3._base64.urlSafeToBuffer(storedObj.privateKey);
var iv = OAUTH3._base64.urlSafeToBuffer(storedObj.ecdsaIv);
return OAUTH3.crypto.core.pbkdf2(password, salt)
.then(function (key) {
return OAUTH3.crypto.core.decrypt(key, iv, encJwk);
})
.then(OAUTH3._binStr.bufferToBinStr)
.then(JSON.parse)
.then(function (privateKey) {
return {
privateKey: privateKey
, publicKey: storedObj.publicKey
, };
});
};
}('undefined' !== typeof exports ? exports : window));