1/*
2 * Copyright (C) 2009 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
17#include <stdint.h>
18#include <utils/Log.h>
19#include <binder/IPCThreadState.h>
20#include <binder/IServiceManager.h>
21#include <binder/Permission.h>
22
23namespace android {
24// ---------------------------------------------------------------------------
25
26Permission::Permission(char const* name)
27    : mPermissionName(name), mPid(getpid())
28{
29}
30
31Permission::Permission(const String16& name)
32    : mPermissionName(name), mPid(getpid())
33{
34}
35
36Permission::Permission(const Permission& rhs)
37    : mPermissionName(rhs.mPermissionName),
38    mGranted(rhs.mGranted),
39    mPid(rhs.mPid)
40{
41}
42
43Permission::~Permission()
44{
45}
46
47bool Permission::operator < (const Permission& rhs) const
48{
49    return mPermissionName < rhs.mPermissionName;
50}
51
52bool Permission::checkCalling() const
53{
54    IPCThreadState* ipcState = IPCThreadState::self();
55    pid_t pid = ipcState->getCallingPid();
56    uid_t uid = ipcState->getCallingUid();
57    return doCheckPermission(pid, uid);
58}
59
60bool Permission::check(pid_t pid, uid_t uid) const
61{
62    return doCheckPermission(pid, uid);
63}
64
65bool Permission::doCheckPermission(pid_t pid, uid_t uid) const
66{
67    if ((uid == 0) || (pid == mPid)) {
68        // root and ourselves is always okay
69        return true;
70    } else {
71        // see if we already granted this permission for this uid
72        Mutex::Autolock _l(mLock);
73        if (mGranted.indexOf(uid) >= 0)
74            return true;
75    }
76
77    bool granted = checkPermission(mPermissionName, pid, uid);
78    if (granted) {
79        Mutex::Autolock _l(mLock);
80        // no need to check again, the old item will be replaced if it is
81        // already there.
82        mGranted.add(uid);
83    }
84    return granted;
85}
86
87// ---------------------------------------------------------------------------
88}; // namespace android
89