1 /*
2  * Copyright (C) 2020 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 #pragma once
18 
19 #include <android/binder_ibinder.h>
20 
21 #if !defined(__ANDROID_APEX__) && !defined(__ANDROID_VNDK__)
22 #include <binder/IBinder.h>
23 #endif
24 
25 __BEGIN_DECLS
26 
27 /**
28  * Makes calls to AIBinder_getCallingSid work if the kernel supports it. This
29  * must be called on a local binder server before it is sent out to any othe
30  * process. If this is a remote binder, it will abort. If the kernel doesn't
31  * support this feature, you'll always get null from AIBinder_getCallingSid.
32  *
33  * \param binder local server binder to request security contexts on
34  */
35 void AIBinder_setRequestingSid(AIBinder* binder, bool requestingSid) __INTRODUCED_IN(31);
36 
37 /**
38  * Returns the selinux context of the callee.
39  *
40  * In order for this to work, the following conditions must be met:
41  * - The kernel must be new enough to support this feature.
42  * - The server must have called AIBinder_setRequestingSid.
43  * - The callee must be a remote process.
44  *
45  * \return security context or null if unavailable. The lifetime of this context
46  * is the lifetime of the transaction.
47  */
48 __attribute__((warn_unused_result)) const char* AIBinder_getCallingSid() __INTRODUCED_IN(31);
49 
50 __END_DECLS
51 
52 #if !defined(__ANDROID_APEX__) && !defined(__ANDROID_VNDK__)
53 
54 /**
55  * Get libbinder version of binder from AIBinder.
56  *
57  * WARNING: function calls to a local object on the other side of this function
58  * will parcel. When converting between binders, keep in mind it is not as
59  * efficient as a direct function call.
60  *
61  * \param binder binder with ownership retained by the client
62  * \return platform binder object
63  */
64 android::sp<android::IBinder> AIBinder_toPlatformBinder(AIBinder* binder);
65 
66 /**
67  * Get libbinder_ndk version of binder from platform binder.
68  *
69  * WARNING: function calls to a local object on the other side of this function
70  * will parcel. When converting between binders, keep in mind it is not as
71  * efficient as a direct function call.
72  *
73  * \param binder platform binder which may be from anywhere (doesn't have to be
74  * created with libbinder_ndK)
75  * \return binder with one reference count of ownership given to the client. See
76  * AIBinder_decStrong
77  */
78 AIBinder* AIBinder_fromPlatformBinder(const android::sp<android::IBinder>& binder);
79 
80 #endif
81