Extension API enterprise.platformKeys.

chrome/renderer/resources/extensions/enterprise_platform_keys_custom_bindings.js

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Custom binding for the enterprise.platformKeys API.
+

[not at google - send to devlin, 2014/05/02 18:31:56]

could you explain what is going on here? there is a lot of code.

have a look at how the Automation is implemented and documented as an example of
a complex custom bindings system:
-
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/renderer/re...
-
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/renderer/re...
-
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/renderer/re...
-
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/renderer/re...

i would find more structure, comments, type annotations, much easier to follow.

[pneubeck (no reviews), 2014/05/05 20:09:35]

Done.

+var binding = require('binding').Binding.create('enterprise.platformKeys');
+var internalAPI = require('binding')
+                      .Binding.create('enterprise.platformKeysInternal')
+                      .generate();
+
+function intersect(a, b) {
+  var result = [];
+  for (var i = 0; i < a.length; i++) {
+    if (b.indexOf(a[i]) >= 0)
+      result.push(a[i]);
+  }
+  return result;
+};
+
+// Key class definition.
+var Key = function(type, publicKeySpki, algorithm, keyUsages) {
+  privates(this).type_ = type;

[not at google - send to devlin, 2014/05/02 18:31:56]

a nice idiom for privates(..) is to have a "KeyImpl" class (or even just a "Key"
class) and then use utils.expose to cherry-pick just the functions/properties
you want to expose to extensions.

[pneubeck (no reviews), 2014/05/05 20:09:35]

Done.

+  privates(this).spki_ = publicKeySpki;
+  privates(this).algorithm_ = algorithm;
+  privates(this).keyUsages_ = keyUsages;
+};
+
+Object.defineProperty(Key.prototype, 'type', {
+  get: function() {
+    return privates(this).type_;
+  },
+  enumerable : true
+});
+
+// PublicKey class definition.
+var PublicKey = function(publicKeySpki, algorithm, keyUsages) {
+  Key.call(this, "public", publicKeySpki, algorithm, keyUsages);
+};
+PublicKey.prototype.__proto__ = Key.prototype;
+
+Object.defineProperty(PublicKey.prototype, 'extractable', {
+  get: function() {
+    return true;
+  },
+  enumerable : true
+});
+
+// PrivateKey class definition.
+var PrivateKey = function(publicKeySpki, algorithm, keyUsages) {
+  Key.call(this, "private", publicKeySpki, algorithm, keyUsages);
+};
+PrivateKey.prototype.__proto__ = Key.prototype;
+
+Object.defineProperty(PrivateKey.prototype, 'extractable', {
+  get: function() {
+    return false;
+  },
+  enumerable : true
+});
+
+// KeyPair class definition.
+var KeyPair = function(publicKeySpki, algorithm, keyUsages) {
+  privates(this).publicKey_ =
+      new PublicKey(publicKeySpki, algorithm, intersect(["verify"], keyUsages));
+  privates(this).privateKey_ =
+      new PrivateKey(publicKeySpki, algorithm, intersect(["sign"], keyUsages));
+};
+
+Object.defineProperty(KeyPair.prototype, 'publicKey', {
+  get: function() {
+    return privates(this).publicKey_;
+  },
+  enumerable : true
+});
+
+Object.defineProperty(KeyPair.prototype, 'privateKey', {
+  get: function() {
+    return privates(this).privateKey_;
+  },
+  enumerable : true
+});
+
+// SublteCrypto implementation.
+var SubtleCrypto = function(tokenId) {
+  privates(this).tokenId_ = tokenId;
+};
+
+function addCryptoMethod(methodName, func) {
+  SubtleCrypto.prototype[methodName] = function() {
+    var subtleCrypto = this;
+    var args = arguments;
+    return new Promise(function(resolve, reject) {
+      try {
+        var tokenId = privates(subtleCrypto).tokenId_;
+        if (!tokenId)
+          throw new Error('Invalid token object');
+
+        var newArgs = [resolve, reject, tokenId];
+        for (var i = 0; i < args.length; i++) {
+          newArgs.push(args[i]);
+        }
+
+        func.apply(null, newArgs);
+      }
+      catch (error) {

[not at google - send to devlin, 2014/05/02 18:31:56]

are exceptions not automatically propagated to failure handlers in promises?

[pneubeck (no reviews), 2014/05/05 20:09:35]

Indeed they are.

+        reject(error);
+      }
+    });
+  }
+}
+
+// Token class definition.
+var Token = function(tokenId) {
+  privates(this).tokenId_ = tokenId;
+  privates(this).subtleCrypto_ = new SubtleCrypto(tokenId);
+};
+
+Object.defineProperty(Token.prototype, 'id', {
+  get: function() {
+    return privates(this).tokenId_;
+  },
+  enumerable : true
+});
+
+Object.defineProperty(Token.prototype, 'subtleCrypto', {
+  get: function() {
+    return privates(this).subtleCrypto_;
+  },
+  enumerable : true
+});
+
+addCryptoMethod(
+    'generateKey',
+    function(resolve, reject, tokenId, algorithm, extractable, keyUsages) {
+      if (extractable)
+        throw new Error('Extractable keys are not supported.');
+      if (intersect(keyUsages, ["sign", "verify"]).length != keyUsages.length) {
+        throw new Error(
+            'Unsupported keyUsages. Only "sign" and "verify" supported.');
+      }
+      if (algorithm.name != 'RSASSA-PKCS1-v1_5')
+        throw new Error('The algorithm is not supported');
+
+      internalAPI.generateKey(tokenId, function(spki) {
+        if (chrome.runtime.lastError) {
+          reject(chrome.runtime.lastError.message);
+          return;
+        }
+        resolve(new KeyPair(spki, algorithm, keyUsages));
+      });
+    });
+
+addCryptoMethod('sign',
+                function(resolve, reject, tokenId, algorithm, key, dataView) {
+  if (!(key instanceof Key))
+    throw new Error('Invalid key.');
+  if (key.type != "private")
+    throw new Error('Key type not supported.');
+
+  // Create an ArrayBuffer that equals the dataView. Note that dataView.buffer
+  // might contain more data than dataView.
+  var data = dataView.buffer.slice(dataView.byteOffset,
+                                   dataView.byteOffset + dataView.byteLength);
+  internalAPI.sign(tokenId, privates(key).spki_, data, function(signature) {
+    if (chrome.runtime.lastError) {
+      reject(chrome.runtime.lastError.message);
+      return;
+    }
+    resolve(signature);
+  });
+});
+
+addCryptoMethod('exportKey', function(resolve, reject, tokenId, format, key) {
+  if (format != 'spki')
+    throw new Error('Format not supported.');
+  if (!(key instanceof Key))
+    throw new Error('Invalid key.');
+  if (key.type != "public")
+    throw new Error('Key type not supported.');
+
+  resolve(privates(key).spki_);
+});
+
+binding.registerCustomHook(function(api) {
+  var apiFunctions = api.apiFunctions;
+
+  var ret = apiFunctions.setHandleRequest('getTokens', function(callback) {
+    internalAPI.getTokens(function(tokenIds) {
+      callback($Array.map(tokenIds,
+                          function(tokenId) { return new Token(tokenId); }));
+    });
+  });
+});
+
+exports.binding = binding.generate();