platformKeys: Add policy and corporate key tagging.

components/policy/resources/policy_templates.json

 {
 # policy_templates.json - Metafile for policy templates
 #
 # The content of this file is evaluated as a Python expression.
 #
 # This file is used as input to generate the following policy templates:
 # ADM, ADMX+ADML, MCX/plist and html documentation.
 #
 # Policy templates are user interface definitions or documents about the
 # policies that can be used to configure Chrome. Each policy is a name-value
@@ skipping 105 matching lines @@
 #   templates and documentation. The policy definition list that Chrome sees
 #   will include policies marked with 'future'. If a WIP policy isn't meant to
 #   be seen by the policy providers either, the 'supported_on' key should be set
 #   to an empty list.
 #
 # IDs:
 #   Since a Protocol Buffer definition is generated from this file, unique and
 #   persistent IDs for all fields (but not for groups!) are needed. These are
 #   specified by the 'id' keys of each policy. NEVER CHANGE EXISTING IDs,
 #   because doing so would break the deployed wire format!
-#   For your editing convenience: highest ID currently used: 301
+#   For your editing convenience: highest ID currently used: 302
 #
 # Placeholders:
 #   The following placeholder strings are automatically substituted:
 #     $1 -> Google Chrome / Chromium
 #     $2 -> Google Chrome OS / Chromium OS
 #     $3 -> Google Chrome Frame / Chromium Frame
 #     $6 is reserved for doc_writer
 #
 # Device Policy:
 #   An additional flag device_only (optional, defaults to False) indicates
@@ skipping 7221 matching lines @@
       'features': {
         'dynamic_refresh': False,
         'per_profile': False,
       },
       'example_value': True,
       'id': 301,
       'caption': '''Allows QUIC protocol''',
       'desc': '''If this policy is set to true or not set usage of QUIC protocol in <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> is allowed.
       If this policy is set to false usage of QUIC protocol is disallowed.''',
     },
+    {
+      'name': 'KeyPermissions',
+      'type': 'dict',
+      'schema': {
+        'type': 'object',
+        'additionalProperties': {
+          'type': 'object',
+          'properties': {
+            'allowCorporateKeyUsage': {
+              'description': '''If set to true, this extension can use all keys, that are designated for corporate usage, to sign arbitrary data. If set to false, it cannot access any such keys and the user cannot grant such permission either.''',
+              'type': 'boolean',
+            },
+          },
+        },
+      },
+      'supported_on': ['chrome_os:45-'],
+      'features': {
+        'dynamic_refresh': True,
+        'per_profile': True,
+      },
+      'example_value': {
+        'extension1': {
+          'allowCorporateKeyUsage': 'true'
+        },
+        'extension2': {
+          'allowCorporateKeyUsage': 'false'
+        }
+      },
+      'id': 302,
+      'caption': 'Key Permissions',
+      'desc': '''Grants usage of platform keys by extensions.

[bartfab (slow), 2015/06/17 09:57:40]

Nit 1: s/usage of/acces to/
Nit 2: s/platform/corportate platform/
Nit 3: s/by/to/

[pneubeck (no reviews), 2015/06/17 13:00:36]

Done.

 
+      By default an extension cannot use a private key managed by the platform for signing data, which is equivalent to setting allowCorporateKeyUsage to false for that extension. A user cannot circumvent that restriction.
+
+      Only if allowCorporateKeyUsage is set to true for an extension, it can use any platform key marked for corporate usage to sign arbitrary data. This permission should only be granted if the extension is trusted to secure access to the key against attackers.''',
+    },

[bartfab (slow), 2015/06/17 09:57:40]

If you do decide to add a bit of explanation, I think it would be easiest to
phrase this description the other way around:

1. Describe what "corporate key" means.
2. State the default (no access).
3. Indicate that this policy can grant access.

[pneubeck (no reviews), 2015/06/17 13:00:36]

Done.

   ],
   'messages': {
     # Messages that are not associated to any policies.
     'win_supported_winxpsp2': {
       'desc': '''A label specifying the oldest possible compatible version of Windows. This text will appear right next to a label containing the text 'Supported on:'.''',
       'text': '''Microsoft Windows XP SP2 or later'''
     },
     'mac_chrome_preferences': {
       'desc': '''A text indicating in Mac OS X Workgroup Manager, that currently the preferences of Chromium are being edited''',
       'text': '''<ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> preferences'''
@@ skipping 105 matching lines @@
       'desc': '''Text appended in parentheses next to the policies top-level container to indicate that those policies are of the Recommended level''',
       'text': 'Default Settings (users can override)',
     },
     'doc_complex_policies_on_windows': {
       'desc': '''Text pointing the user to a help article for complex policies on Windows''',
       'text': '''encoded as a JSON string, for details see <ph name="COMPLEX_POLICIES_URL">http://www.chromium.org/administrators/complex-policies-on-windows<ex>http://www.chromium.org/administrators/complex-policies-on-windows</ex></ph>''',
     },
   },
   'placeholders': [],
 }