1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.server.firewall;
18
19import android.content.ComponentName;
20import android.content.Intent;
21import org.xmlpull.v1.XmlPullParser;
22import org.xmlpull.v1.XmlPullParserException;
23
24import java.io.IOException;
25
26class SenderPermissionFilter implements Filter {
27    private static final String ATTR_NAME = "name";
28
29    private final String mPermission;
30
31    private SenderPermissionFilter(String permission) {
32        mPermission = permission;
33    }
34
35    @Override
36    public boolean matches(IntentFirewall ifw, ComponentName resolvedComponent, Intent intent,
37            int callerUid, int callerPid, String resolvedType, int receivingUid) {
38        // We assume the component is exported here. If the component is not exported, then
39        // ActivityManager would only resolve to this component for callers from the same uid.
40        // In this case, it doesn't matter whether the component is exported or not.
41        return ifw.checkComponentPermission(mPermission, callerPid, callerUid, receivingUid,
42                true);
43    }
44
45    public static final FilterFactory FACTORY = new FilterFactory("sender-permission") {
46        @Override
47        public Filter newFilter(XmlPullParser parser)
48                throws IOException, XmlPullParserException {
49            String permission = parser.getAttributeValue(null, ATTR_NAME);
50            if (permission == null) {
51                throw new XmlPullParserException("Permission name must be specified.",
52                        parser, null);
53            }
54            return new SenderPermissionFilter(permission);
55        }
56    };
57}
58