1/*
2 * Copyright (C) 2010 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.am;
18
19import android.content.Intent;
20import android.os.Binder;
21import android.os.IBinder;
22import android.util.ArraySet;
23import android.util.proto.ProtoOutputStream;
24
25import com.google.android.collect.Sets;
26
27import java.io.PrintWriter;
28import java.util.Iterator;
29
30final class UriPermissionOwner {
31    final ActivityManagerService service;
32    final Object owner;
33
34    Binder externalToken;
35
36    private ArraySet<UriPermission> mReadPerms;
37    private ArraySet<UriPermission> mWritePerms;
38
39    class ExternalToken extends Binder {
40        UriPermissionOwner getOwner() {
41            return UriPermissionOwner.this;
42        }
43    }
44
45    UriPermissionOwner(ActivityManagerService service, Object owner) {
46        this.service = service;
47        this.owner = owner;
48    }
49
50    Binder getExternalTokenLocked() {
51        if (externalToken == null) {
52            externalToken = new ExternalToken();
53        }
54        return externalToken;
55    }
56
57    static UriPermissionOwner fromExternalToken(IBinder token) {
58        if (token instanceof ExternalToken) {
59            return ((ExternalToken)token).getOwner();
60        }
61        return null;
62    }
63
64    void removeUriPermissionsLocked() {
65        removeUriPermissionsLocked(Intent.FLAG_GRANT_READ_URI_PERMISSION
66                | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
67    }
68
69    void removeUriPermissionsLocked(int mode) {
70        removeUriPermissionLocked(null, mode);
71    }
72
73    void removeUriPermissionLocked(ActivityManagerService.GrantUri grantUri, int mode) {
74        if ((mode & Intent.FLAG_GRANT_READ_URI_PERMISSION) != 0
75                && mReadPerms != null) {
76            Iterator<UriPermission> it = mReadPerms.iterator();
77            while (it.hasNext()) {
78                UriPermission perm = it.next();
79                if (grantUri == null || grantUri.equals(perm.uri)) {
80                    perm.removeReadOwner(this);
81                    service.removeUriPermissionIfNeededLocked(perm);
82                    it.remove();
83                }
84            }
85            if (mReadPerms.isEmpty()) {
86                mReadPerms = null;
87            }
88        }
89        if ((mode & Intent.FLAG_GRANT_WRITE_URI_PERMISSION) != 0
90                && mWritePerms != null) {
91            Iterator<UriPermission> it = mWritePerms.iterator();
92            while (it.hasNext()) {
93                UriPermission perm = it.next();
94                if (grantUri == null || grantUri.equals(perm.uri)) {
95                    perm.removeWriteOwner(this);
96                    service.removeUriPermissionIfNeededLocked(perm);
97                    it.remove();
98                }
99            }
100            if (mWritePerms.isEmpty()) {
101                mWritePerms = null;
102            }
103        }
104    }
105
106    public void addReadPermission(UriPermission perm) {
107        if (mReadPerms == null) {
108            mReadPerms = Sets.newArraySet();
109        }
110        mReadPerms.add(perm);
111    }
112
113    public void addWritePermission(UriPermission perm) {
114        if (mWritePerms == null) {
115            mWritePerms = Sets.newArraySet();
116        }
117        mWritePerms.add(perm);
118    }
119
120    public void removeReadPermission(UriPermission perm) {
121        mReadPerms.remove(perm);
122        if (mReadPerms.isEmpty()) {
123            mReadPerms = null;
124        }
125    }
126
127    public void removeWritePermission(UriPermission perm) {
128        mWritePerms.remove(perm);
129        if (mWritePerms.isEmpty()) {
130            mWritePerms = null;
131        }
132    }
133
134    public void dump(PrintWriter pw, String prefix) {
135        if (mReadPerms != null) {
136            pw.print(prefix); pw.print("readUriPermissions="); pw.println(mReadPerms);
137        }
138        if (mWritePerms != null) {
139            pw.print(prefix); pw.print("writeUriPermissions="); pw.println(mWritePerms);
140        }
141    }
142
143    public void writeToProto(ProtoOutputStream proto, long fieldId) {
144        long token = proto.start(fieldId);
145        proto.write(UriPermissionOwnerProto.OWNER, owner.toString());
146        if (mReadPerms != null) {
147            synchronized (mReadPerms) {
148                for (UriPermission p : mReadPerms) {
149                    p.uri.writeToProto(proto, UriPermissionOwnerProto.READ_PERMS);
150                }
151            }
152        }
153        if (mWritePerms != null) {
154            synchronized (mWritePerms) {
155                for (UriPermission p : mWritePerms) {
156                    p.uri.writeToProto(proto, UriPermissionOwnerProto.WRITE_PERMS);
157                }
158            }
159        }
160        proto.end(token);
161    }
162
163    @Override
164    public String toString() {
165        return owner.toString();
166    }
167}
168