1/*
2 * Copyright (C) 2011 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 <cutils/log.h>
18#include <cutils/sockets.h>
19
20#ifdef HAVE_ANDROID_OS
21/* For the socket trust (credentials) check */
22#include <private/android_filesystem_config.h>
23#endif
24
25bool socket_peer_is_trusted(int fd)
26{
27#ifdef HAVE_ANDROID_OS
28    struct ucred cr;
29    socklen_t len = sizeof(cr);
30    int n = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &cr, &len);
31
32    if (n != 0) {
33        ALOGE("could not get socket credentials: %s\n", strerror(errno));
34        return false;
35    }
36
37    if ((cr.uid != AID_ROOT) && (cr.uid != AID_SHELL)) {
38        ALOGE("untrusted userid on other end of socket: userid %d\n", cr.uid);
39        return false;
40    }
41#endif
42
43    return true;
44}
45