1651f8383e66a32741d78f485c714ced345db7b3dVijay Venkatraman/*
2 * Copyright (C) 2006 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#ifndef __CUTILS_SOCKETS_H
18#define __CUTILS_SOCKETS_H
19
20#include <errno.h>
21#include <limits.h>
22#include <stdio.h>
23#include <stdlib.h>
24#include <string.h>
25#include <stdbool.h>
26
27#if defined(_WIN32)
28
29#include <winsock2.h>
30#include <ws2tcpip.h>
31
32typedef int  socklen_t;
33typedef SOCKET cutils_socket_t;
34
35#else
36
37#include <sys/socket.h>
38#include <netinet/in.h>
39
40typedef int cutils_socket_t;
41#define INVALID_SOCKET (-1)
42
43#endif
44
45#define ANDROID_SOCKET_ENV_PREFIX	"ANDROID_SOCKET_"
46#define ANDROID_SOCKET_DIR		"/dev/socket"
47
48#ifdef __cplusplus
49extern "C" {
50#endif
51
52/*
53 * android_get_control_socket - simple helper function to get the file
54 * descriptor of our init-managed Unix domain socket. `name' is the name of the
55 * socket, as given in init.rc. Returns -1 on error.
56 */
57int android_get_control_socket(const char* name);
58
59/*
60 * See also android.os.LocalSocketAddress.Namespace
61 */
62// Linux "abstract" (non-filesystem) namespace
63#define ANDROID_SOCKET_NAMESPACE_ABSTRACT 0
64// Android "reserved" (/dev/socket) namespace
65#define ANDROID_SOCKET_NAMESPACE_RESERVED 1
66// Normal filesystem namespace
67#define ANDROID_SOCKET_NAMESPACE_FILESYSTEM 2
68
69/*
70 * Functions to create sockets for some common usages.
71 *
72 * All these functions are implemented for Unix, but only a few are implemented
73 * for Windows. Those which are can be identified by the cutils_socket_t
74 * return type. The idea is to be able to use this return value with the
75 * standard Unix socket functions on any platform.
76 *
77 * On Unix the returned cutils_socket_t is a standard int file descriptor and
78 * can always be used as normal with all file descriptor functions.
79 *
80 * On Windows utils_socket_t is an unsigned int pointer, and is only valid
81 * with functions that specifically take a socket, e.g. send(), sendto(),
82 * recv(), and recvfrom(). General file descriptor functions such as read(),
83 * write(), and close() will not work with utils_socket_t and will require
84 * special handling.
85 *
86 * These functions return INVALID_SOCKET (-1) on failure for all platforms.
87 */
88cutils_socket_t socket_network_client(const char* host, int port, int type);
89int socket_network_client_timeout(const char* host, int port, int type,
90                                  int timeout, int* getaddrinfo_error);
91int socket_loopback_server(int port, int type);
92int socket_loopback_server6(int port, int type);
93int socket_local_server(const char* name, int namespaceId, int type);
94int socket_local_server_bind(int s, const char* name, int namespaceId);
95int socket_local_client_connect(int fd, const char *name, int namespaceId,
96                                int type);
97int socket_local_client(const char* name, int namespaceId, int type);
98cutils_socket_t socket_inaddr_any_server(int port, int type);
99
100/*
101 * Closes a cutils_socket_t. Windows doesn't allow calling close() on a socket
102 * so this is a cross-platform way to close a cutils_socket_t.
103 *
104 * Returns 0 on success.
105 */
106int socket_close(cutils_socket_t sock);
107
108/*
109 * Sets socket receive timeout using SO_RCVTIMEO. Setting |timeout_ms| to 0
110 * disables receive timeouts.
111 *
112 * Return 0 on success.
113 */
114int socket_set_receive_timeout(cutils_socket_t sock, int timeout_ms);
115
116/*
117 * Returns the local port the socket is bound to or -1 on error.
118 */
119int socket_get_local_port(cutils_socket_t sock);
120
121/*
122 * Sends to a socket from multiple buffers; wraps writev() on Unix or WSASend()
123 * on Windows. This can give significant speedup compared to calling send()
124 * multiple times.
125 *
126 * Example usage:
127 *   cutils_socket_buffer_t buffers[2] = { {data0, len0}, {data1, len1} };
128 *   socket_send_buffers(sock, buffers, 2);
129 *
130 * If you try to pass more than SOCKET_SEND_BUFFERS_MAX_BUFFERS buffers into
131 * this function it will return -1 without sending anything.
132 *
133 * Returns the number of bytes written or -1 on error.
134 */
135typedef struct {
136  const void* data;
137  size_t length;
138} cutils_socket_buffer_t;
139
140#define SOCKET_SEND_BUFFERS_MAX_BUFFERS 16
141
142ssize_t socket_send_buffers(cutils_socket_t sock,
143                            const cutils_socket_buffer_t* buffers,
144                            size_t num_buffers);
145
146/*
147 * socket_peer_is_trusted - Takes a socket which is presumed to be a
148 * connected local socket (e.g. AF_LOCAL) and returns whether the peer
149 * (the userid that owns the process on the other end of that socket)
150 * is one of the two trusted userids, root or shell.
151 *
152 * Note: This only works as advertised on the Android OS and always
153 * just returns true when called on other operating systems.
154 */
155extern bool socket_peer_is_trusted(int fd);
156
157#ifdef __cplusplus
158}
159#endif
160
161#endif /* __CUTILS_SOCKETS_H */
162