1 /*
2  * Copyright (C) 2016 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 #define LOG_TAG "ShellCallback"
18 
19 #include <unistd.h>
20 #include <fcntl.h>
21 
22 #include <binder/IShellCallback.h>
23 
24 #include <utils/Log.h>
25 #include <binder/Parcel.h>
26 #include <utils/String8.h>
27 
28 namespace android {
29 
30 // ----------------------------------------------------------------------
31 
32 class BpShellCallback : public BpInterface<IShellCallback>
33 {
34 public:
BpShellCallback(const sp<IBinder> & impl)35     explicit BpShellCallback(const sp<IBinder>& impl)
36         : BpInterface<IShellCallback>(impl)
37     {
38     }
39 
openFile(const String16 & path,const String16 & seLinuxContext,const String16 & mode)40     virtual int openFile(const String16& path, const String16& seLinuxContext,
41             const String16& mode) {
42         Parcel data, reply;
43         data.writeInterfaceToken(IShellCallback::getInterfaceDescriptor());
44         data.writeString16(path);
45         data.writeString16(seLinuxContext);
46         data.writeString16(mode);
47         remote()->transact(OP_OPEN_OUTPUT_FILE, data, &reply, 0);
48         reply.readExceptionCode();
49         int fd = reply.readParcelFileDescriptor();
50         return fd >= 0 ? fcntl(fd, F_DUPFD_CLOEXEC, 0) : fd;
51 
52     }
53 };
54 
55 IMPLEMENT_META_INTERFACE(ShellCallback, "com.android.internal.os.IShellCallback")
56 
57 // ----------------------------------------------------------------------
58 
59 // NOLINTNEXTLINE(google-default-arguments)
60 status_t BnShellCallback::onTransact(
61     uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
62 {
63     switch(code) {
64         case OP_OPEN_OUTPUT_FILE: {
65             CHECK_INTERFACE(IShellCallback, data, reply);
66             String16 path(data.readString16());
67             String16 seLinuxContext(data.readString16());
68             String16 mode(data.readString16());
69             int fd = openFile(path, seLinuxContext, mode);
70             if (reply != nullptr) {
71                 reply->writeNoException();
72                 if (fd >= 0) {
73                     reply->writeInt32(1);
74                     reply->writeParcelFileDescriptor(fd, true);
75                 } else {
76                     reply->writeInt32(0);
77                 }
78             } else if (fd >= 0) {
79                 close(fd);
80             }
81             return NO_ERROR;
82         } break;
83         default:
84             return BBinder::onTransact(code, data, reply, flags);
85     }
86 }
87 
88 } // namespace android
89