Block off commands on a server for certain user groups.

This feature adds two new options to gerrit.config file: upload and
receive with the allowGroup attribute, that restrict to some specific
groups the ability to run upload/receive commands on the server.

[sp: All bugs are mine, I refactored the code a bit from the original]

Change-Id: Ibd31bd11234e429f8b0201bbb03099f737281f21
Signed-off-by: Shawn O. Pearce <sop@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/config/GitReceivePackGroupsProvider.java

@@ -0,0 +1,42 @@
+// Copyright (C) 2010 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License
+
+package com.google.gerrit.server.config;
+
+import com.google.gerrit.reviewdb.AccountGroup;
+import com.google.gerrit.reviewdb.ReviewDb;
+import com.google.gwtorm.client.SchemaFactory;
+import com.google.inject.Inject;
+
+import org.eclipse.jgit.lib.Config;
+
+import java.util.Collections;
+import java.util.HashSet;
+
+public class GitReceivePackGroupsProvider extends GroupSetProvider {
+  @Inject
+  public GitReceivePackGroupsProvider(@GerritServerConfig Config config,
+      AuthConfig authConfig, SchemaFactory<ReviewDb> db) {
+    super(config, db, "receive", null, "allowGroup");
+
+    // If no group was set, default to "registered users"
+    //
+    if (groupIds.isEmpty()) {
+      HashSet<AccountGroup.Id> all = new HashSet<AccountGroup.Id>();
+      all.addAll(authConfig.getRegisteredGroups());
+      all.removeAll(authConfig.getAnonymousGroups());
+      groupIds = Collections.unmodifiableSet(all);
+    }
+  }
+}