Implement chrome.platformKeys.getKeyPair().

chrome/renderer/resources/extensions/platform_keys/get_public_key.js

+// Copyright 2015 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.
+
+var internalAPI = require('platformKeys.internalAPI');
+
+var normalizeAlgorithm =
+    requireNative('platform_keys_natives').NormalizeAlgorithm;
+
+function combineAlgorithms(algorithm, importParams) {
+  if (importParams.name === undefined) {
+    importParams.name = algorithm.name;
+  }
+
+  // Verify whether importParams.hash equals
+  //   { name: 'none' }
+  if (importParams.hash &&
+      importParams.hash.name.toLowerCase() === 'none') {
+    if (Object.keys(importParams.hash).length != 1 ||
+        Object.keys(importParams).length != 2) {
+      // 'name' must be the only hash property in this case.
+      throw new Error('A required parameter was missing or out-of-range');
+    }
+    importParams.hash.name = 'none';
+  } else {
+    // Otherwise apply WebCrypto's algorithm normalization.
+    importParams = normalizeAlgorithm(importParams, 'ImportKey');
+    if (!importParams) {
+      //    throw CreateSyntaxError();
+      throw new Error('A required parameter was missing or out-of-range');
+    }
+  }
+
+  if (algorithm.publicExponent) {
+    algorithm.publicExponent = new Uint8Array(algorithm.publicExponent);

[Ryan Sleevi, 2015/02/03 01:44:50]

BUG? The point of WebCrypto is to ensure the import params match. Is this really
correct here?

[pneubeck (no reviews), 2015/02/03 20:15:00]

added a comment explaining that this only fixes the type of the publicExponent
returned by the internal API.

regarding whether the import params match the key properties:
I currently don't check for any match and instead overwrite the import params
with the params that I read from the SPKI.

+  }
+
+  for (var key in importParams) {
+    algorithm[key] = importParams[key];
+  }
+
+  return algorithm;
+}
+
+function getPublicKey(cert, importParams, callback) {
+  internalAPI.getPublicKey(cert, function(publicKey, algorithm) {
+    var combinedAlgorithm = combineAlgorithms(algorithm, importParams);
+    callback(publicKey, combinedAlgorithm);
+  });
+}
+
+exports.getPublicKey = getPublicKey;