1 /******************************************************************************
2  *
3  *  Copyright (C) 2014 Google, Inc.
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at:
8  *
9  *  http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  ******************************************************************************/
18 
19 #define LOG_TAG "bt_osi_socket"
20 
21 #include <asm/ioctls.h>
22 #include <assert.h>
23 #include <errno.h>
24 #include <netinet/in.h>
25 #include <string.h>
26 #include <sys/ioctl.h>
27 #include <sys/socket.h>
28 #include <sys/types.h>
29 #include <unistd.h>
30 
31 #include "osi/include/allocator.h"
32 #include "osi/include/osi.h"
33 #include "osi/include/log.h"
34 #include "osi/include/reactor.h"
35 #include "osi/include/socket.h"
36 
37 // The IPv4 loopback address: 127.0.0.1
38 static const in_addr_t LOCALHOST_ = 0x7f000001;
39 
40 struct socket_t {
41   int fd;
42   reactor_object_t *reactor_object;
43   socket_cb read_ready;
44   socket_cb write_ready;
45   void *context;                     // Not owned, do not free.
46 };
47 
48 static void internal_read_ready(void *context);
49 static void internal_write_ready(void *context);
50 
socket_new(void)51 socket_t *socket_new(void) {
52   socket_t *ret = (socket_t *)osi_calloc(sizeof(socket_t));
53   if (!ret) {
54     LOG_ERROR("%s unable to allocate memory for socket.", __func__);
55     goto error;
56   }
57 
58   ret->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
59   if (ret->fd == INVALID_FD) {
60     LOG_ERROR("%s unable to create socket: %s", __func__, strerror(errno));
61     goto error;
62   }
63 
64   int enable = 1;
65   if (setsockopt(ret->fd, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(enable)) == -1) {
66     LOG_ERROR("%s unable to set SO_REUSEADDR: %s", __func__, strerror(errno));
67     goto error;
68   }
69 
70   return ret;
71 
72 error:;
73   if (ret)
74     close(ret->fd);
75   osi_free(ret);
76   return NULL;
77 }
78 
socket_new_from_fd(int fd)79 socket_t *socket_new_from_fd(int fd) {
80   assert(fd != INVALID_FD);
81 
82   socket_t *ret = (socket_t *)osi_calloc(sizeof(socket_t));
83   if (!ret) {
84     LOG_ERROR("%s unable to allocate memory for socket.", __func__);
85     return NULL;
86   }
87 
88   ret->fd = fd;
89   return ret;
90 }
91 
socket_free(socket_t * socket)92 void socket_free(socket_t *socket) {
93   if (!socket)
94     return;
95 
96   socket_unregister(socket);
97   close(socket->fd);
98   osi_free(socket);
99 }
100 
socket_listen(const socket_t * socket,port_t port)101 bool socket_listen(const socket_t *socket, port_t port) {
102   assert(socket != NULL);
103 
104   struct sockaddr_in addr;
105   addr.sin_family = AF_INET;
106   addr.sin_addr.s_addr = htonl(LOCALHOST_);
107   addr.sin_port = htons(port);
108   if (bind(socket->fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
109     LOG_ERROR("%s unable to bind socket to port %u: %s", __func__, port, strerror(errno));
110     return false;
111   }
112 
113   if (listen(socket->fd, 10) == -1) {
114     LOG_ERROR("%s unable to listen on port %u: %s", __func__, port, strerror(errno));
115     return false;
116   }
117 
118   return true;
119 }
120 
socket_accept(const socket_t * socket)121 socket_t *socket_accept(const socket_t *socket) {
122   assert(socket != NULL);
123 
124   int fd = accept(socket->fd, NULL, NULL);
125   if (fd == INVALID_FD) {
126     LOG_ERROR("%s unable to accept socket: %s", __func__, strerror(errno));
127     return NULL;
128   }
129 
130   socket_t *ret = (socket_t *)osi_calloc(sizeof(socket_t));
131   if (!ret) {
132     close(fd);
133     LOG_ERROR("%s unable to allocate memory for socket.", __func__);
134     return NULL;
135   }
136 
137   ret->fd = fd;
138   return ret;
139 }
140 
socket_read(const socket_t * socket,void * buf,size_t count)141 ssize_t socket_read(const socket_t *socket, void *buf, size_t count) {
142   assert(socket != NULL);
143   assert(buf != NULL);
144 
145   return recv(socket->fd, buf, count, MSG_DONTWAIT);
146 }
147 
socket_write(const socket_t * socket,const void * buf,size_t count)148 ssize_t socket_write(const socket_t *socket, const void *buf, size_t count) {
149   assert(socket != NULL);
150   assert(buf != NULL);
151 
152   return send(socket->fd, buf, count, MSG_DONTWAIT);
153 }
154 
socket_write_and_transfer_fd(const socket_t * socket,const void * buf,size_t count,int fd)155 ssize_t socket_write_and_transfer_fd(const socket_t *socket, const void *buf, size_t count, int fd) {
156   assert(socket != NULL);
157   assert(buf != NULL);
158 
159   if (fd == INVALID_FD)
160     return socket_write(socket, buf, count);
161 
162   struct msghdr msg;
163   struct iovec iov;
164   char control_buf[CMSG_SPACE(sizeof(int))];
165 
166   iov.iov_base = (void *)buf;
167   iov.iov_len = count;
168 
169   msg.msg_iov = &iov;
170   msg.msg_iovlen = 1;
171   msg.msg_control = control_buf;
172   msg.msg_controllen = sizeof(control_buf);
173   msg.msg_name = NULL;
174   msg.msg_namelen = 0;
175 
176   struct cmsghdr *header = CMSG_FIRSTHDR(&msg);
177   header->cmsg_level = SOL_SOCKET;
178   header->cmsg_type = SCM_RIGHTS;
179   header->cmsg_len = CMSG_LEN(sizeof(int));
180   *(int *)CMSG_DATA(header) = fd;
181 
182   ssize_t ret = sendmsg(socket->fd, &msg, MSG_DONTWAIT);
183   close(fd);
184   return ret;
185 }
186 
socket_bytes_available(const socket_t * socket)187 ssize_t socket_bytes_available(const socket_t *socket) {
188   assert(socket != NULL);
189 
190   int size = 0;
191   if (ioctl(socket->fd, FIONREAD, &size) == -1)
192     return -1;
193   return size;
194 }
195 
socket_register(socket_t * socket,reactor_t * reactor,void * context,socket_cb read_cb,socket_cb write_cb)196 void socket_register(socket_t *socket, reactor_t *reactor, void *context, socket_cb read_cb, socket_cb write_cb) {
197   assert(socket != NULL);
198 
199   // Make sure the socket isn't currently registered.
200   socket_unregister(socket);
201 
202   socket->read_ready = read_cb;
203   socket->write_ready = write_cb;
204   socket->context = context;
205 
206   void (*read_fn)(void *) = (read_cb != NULL) ? internal_read_ready : NULL;
207   void (*write_fn)(void *) = (write_cb != NULL) ? internal_write_ready : NULL;
208 
209   socket->reactor_object = reactor_register(reactor, socket->fd, socket, read_fn, write_fn);
210 }
211 
socket_unregister(socket_t * socket)212 void socket_unregister(socket_t *socket) {
213   assert(socket != NULL);
214 
215   if (socket->reactor_object)
216     reactor_unregister(socket->reactor_object);
217   socket->reactor_object = NULL;
218 }
219 
internal_read_ready(void * context)220 static void internal_read_ready(void *context) {
221   assert(context != NULL);
222 
223   socket_t *socket = (void *)context;
224   socket->read_ready(socket, socket->context);
225 }
226 
internal_write_ready(void * context)227 static void internal_write_ready(void *context) {
228   assert(context != NULL);
229 
230   socket_t *socket = (void *)context;
231   socket->write_ready(socket, socket->context);
232 }
233