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/sockets.h>
18
19#include <sys/uio.h>
20
21#include <log/log.h>
22
23#if defined(__ANDROID__)
24/* For the socket trust (credentials) check */
25#include <private/android_filesystem_config.h>
26#define __android_unused
27#else
28#define __android_unused __attribute__((__unused__))
29#endif
30
31bool socket_peer_is_trusted(int fd __android_unused) {
32#if defined(__ANDROID__)
33    ucred cr;
34    socklen_t len = sizeof(cr);
35    int n = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &cr, &len);
36
37    if (n != 0) {
38        ALOGE("could not get socket credentials: %s\n", strerror(errno));
39        return false;
40    }
41
42    if ((cr.uid != AID_ROOT) && (cr.uid != AID_SHELL)) {
43        ALOGE("untrusted userid on other end of socket: userid %d\n", cr.uid);
44        return false;
45    }
46#endif
47
48    return true;
49}
50
51int socket_close(int sock) {
52    return close(sock);
53}
54
55int socket_set_receive_timeout(cutils_socket_t sock, int timeout_ms) {
56    timeval tv;
57    tv.tv_sec = timeout_ms / 1000;
58    tv.tv_usec = (timeout_ms % 1000) * 1000;
59    return setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
60}
61
62ssize_t socket_send_buffers(cutils_socket_t sock,
63                            const cutils_socket_buffer_t* buffers,
64                            size_t num_buffers) {
65    if (num_buffers > SOCKET_SEND_BUFFERS_MAX_BUFFERS) {
66        return -1;
67    }
68
69    iovec iovec_buffers[SOCKET_SEND_BUFFERS_MAX_BUFFERS];
70    for (size_t i = 0; i < num_buffers; ++i) {
71        // It's safe to cast away const here; iovec declares non-const
72        // void* because it's used for both send and receive, but since
73        // we're only sending, the data won't be modified.
74        iovec_buffers[i].iov_base = const_cast<void*>(buffers[i].data);
75        iovec_buffers[i].iov_len = buffers[i].length;
76    }
77
78    return writev(sock, iovec_buffers, num_buffers);
79}
80