1 /* 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 32 typedef int socklen_t; 33 typedef SOCKET cutils_socket_t; 34 35 #else 36 37 #include <sys/socket.h> 38 #include <netinet/in.h> 39 40 typedef 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 49 extern "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 */ 57 int 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 */ 88 cutils_socket_t socket_network_client(const char* host, int port, int type); 89 int socket_network_client_timeout(const char* host, int port, int type, 90 int timeout, int* getaddrinfo_error); 91 int socket_local_server(const char* name, int namespaceId, int type); 92 int socket_local_server_bind(int s, const char* name, int namespaceId); 93 int socket_local_client_connect(int fd, const char *name, int namespaceId, 94 int type); 95 int socket_local_client(const char* name, int namespaceId, int type); 96 cutils_socket_t socket_inaddr_any_server(int port, int type); 97 98 /* 99 * Closes a cutils_socket_t. Windows doesn't allow calling close() on a socket 100 * so this is a cross-platform way to close a cutils_socket_t. 101 * 102 * Returns 0 on success. 103 */ 104 int socket_close(cutils_socket_t sock); 105 106 /* 107 * Sets socket receive timeout using SO_RCVTIMEO. Setting |timeout_ms| to 0 108 * disables receive timeouts. 109 * 110 * Return 0 on success. 111 */ 112 int socket_set_receive_timeout(cutils_socket_t sock, int timeout_ms); 113 114 /* 115 * Returns the local port the socket is bound to or -1 on error. 116 */ 117 int socket_get_local_port(cutils_socket_t sock); 118 119 /* 120 * Sends to a socket from multiple buffers; wraps writev() on Unix or WSASend() 121 * on Windows. This can give significant speedup compared to calling send() 122 * multiple times. 123 * 124 * Example usage: 125 * cutils_socket_buffer_t buffers[2] = { {data0, len0}, {data1, len1} }; 126 * socket_send_buffers(sock, buffers, 2); 127 * 128 * If you try to pass more than SOCKET_SEND_BUFFERS_MAX_BUFFERS buffers into 129 * this function it will return -1 without sending anything. 130 * 131 * Returns the number of bytes written or -1 on error. 132 */ 133 typedef struct { 134 const void* data; 135 size_t length; 136 } cutils_socket_buffer_t; 137 138 #define SOCKET_SEND_BUFFERS_MAX_BUFFERS 16 139 140 ssize_t socket_send_buffers(cutils_socket_t sock, 141 const cutils_socket_buffer_t* buffers, 142 size_t num_buffers); 143 144 /* 145 * socket_peer_is_trusted - Takes a socket which is presumed to be a 146 * connected local socket (e.g. AF_LOCAL) and returns whether the peer 147 * (the userid that owns the process on the other end of that socket) 148 * is one of the two trusted userids, root or shell. 149 * 150 * Note: This only works as advertised on the Android OS and always 151 * just returns true when called on other operating systems. 152 */ 153 extern bool socket_peer_is_trusted(int fd); 154 155 #ifdef __cplusplus 156 } 157 #endif 158 159 #endif /* __CUTILS_SOCKETS_H */ 160