blob: 7a352a1d8fc2c9aa666a29dcec891e8a6d8746e4 [file] [log] [blame]
San Mehat9d10b342010-01-18 09:51:02 -08001/*
2 * Copyright (C) 2008 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 <stdlib.h>
18#include <errno.h>
19#include <sys/socket.h>
20#include <sys/stat.h>
21#include <fcntl.h>
22#include <netinet/in.h>
23#include <arpa/inet.h>
24
25#define LOG_TAG "TetherController"
26#include <cutils/log.h>
27
28
29#include "TetherController.h"
30
31TetherController::TetherController() {
32 mInterfaces = new InterfaceCollection();
33 mDnsForwarders = new NetAddressCollection();
34 mDaemonFd = -1;
35 mDaemonPid = 0;
36}
37
38TetherController::~TetherController() {
39 InterfaceCollection::iterator it;
40
41 for (it = mInterfaces->begin(); it != mInterfaces->end(); ++it) {
42 free(*it);
43 }
44 mInterfaces->clear();
45
46 mDnsForwarders->clear();
47}
48
49int TetherController::setIpFwdEnabled(bool enable) {
50
51 LOGD("Setting IP forward enable = %d", enable);
52 int fd = open("/proc/sys/net/ipv4/ip_forward", O_WRONLY);
53 if (fd < 0) {
54 LOGE("Failed to open ip_forward (%s)", strerror(errno));
55 return -1;
56 }
57
58 if (write(fd, (enable ? "1" : "0"), 1) != 1) {
59 LOGE("Failed to write ip_forward (%s)", strerror(errno));
60 return -1;
61 }
62 close(fd);
63 return 0;
64}
65
66bool TetherController::getIpFwdEnabled() {
67 int fd = open("/proc/sys/net/ipv4/ip_forward", O_RDONLY);
68
69 if (fd < 0) {
70 LOGE("Failed to open ip_forward (%s)", strerror(errno));
71 return false;
72 }
73
74 char enabled;
75 if (read(fd, &enabled, 1) != 1) {
76 LOGE("Failed to read ip_forward (%s)", strerror(errno));
77 return -1;
78 }
79
80 close(fd);
81
82 return (enabled == '1' ? true : false);
83}
84
85int TetherController::startTethering(struct in_addr dhcpStart, struct in_addr dhcpEnd) {
86
87 if (mDaemonPid != 0) {
88 LOGE("Tethering already started");
89 errno = EBUSY;
90 return -1;
91 }
92
93 LOGD("Starting tethering services");
94
95 pid_t pid;
96 int pipefd[2];
97
98 if (pipe(pipefd) < 0) {
99 LOGE("pipe failed (%s)", strerror(errno));
100 return -1;
101 }
102
103 /*
104 * TODO: Create a monitoring thread to handle and restart
105 * the daemon if it exits prematurely
106 */
107 if ((pid = fork()) < 0) {
108 LOGE("fork failed (%s)", strerror(errno));
109 close(pipefd[0]);
110 close(pipefd[1]);
111 return -1;
112 }
113
114 if (!pid) {
115 close(pipefd[1]);
116 if (pipefd[0] != STDIN_FILENO) {
117 if (dup2(pipefd[0], STDIN_FILENO) != STDIN_FILENO) {
118 LOGE("dup2 failed (%s)", strerror(errno));
119 return -1;
120 }
121 close(pipefd[0]);
122 }
123 char *start = strdup(inet_ntoa(dhcpStart));
124 char *end = strdup(inet_ntoa(dhcpEnd));
125 char *range;
126
127 asprintf(&range, "--dhcp-range=%s,%s,1h", start, end);
128
129 if (execl("/system/bin/dnsmasq", "/system/bin/dnsmasq", "--no-daemon", "--no-resolv",
130 "--no-poll", "--no-hosts", range, (char *) NULL)) {
131 LOGE("execl failed (%s)", strerror(errno));
132 }
133 LOGE("Should never get here!");
134 return 0;
135 } else {
136 close(pipefd[0]);
137 mDaemonPid = pid;
138 mDaemonFd = pipefd[1];
139 LOGD("Tethering services running");
140 }
141
142 return 0;
143}
144
145int TetherController::stopTethering() {
146
147 if (mDaemonPid == 0) {
148 LOGE("Tethering already stopped");
149 return 0;
150 }
151
152 LOGD("Stopping tethering services");
153
154 kill(mDaemonPid, SIGTERM);
155 mDaemonPid = 0;
156 close(mDaemonFd);
157 mDaemonFd = -1;
158 return 0;
159}
160
161bool TetherController::isTetheringStarted() {
162 return (mDaemonPid == 0 ? false : true);
163}
164
165int TetherController::setDnsForwarders(char **servers, int numServers) {
166 int i;
167 char daemonCmd[1024];
168
169 strcpy(daemonCmd, "update_dns");
170
171 mDnsForwarders->clear();
172 for (i = 0; i < numServers; i++) {
173 LOGD("setDnsForwarders(%d = '%s')", i, servers[i]);
174
175 struct in_addr a;
176
177 if (!inet_aton(servers[i], &a)) {
178 LOGE("Failed to parse DNS server '%s'", servers[i]);
179 mDnsForwarders->clear();
180 return -1;
181 }
182 strcat(daemonCmd, ":");
183 strcat(daemonCmd, servers[i]);
184 mDnsForwarders->push_back(a);
185 }
186
187 if (mDaemonFd != -1) {
188 LOGD("Sending update msg to dnsmasq [%s]", daemonCmd);
189 if (write(mDaemonFd, daemonCmd, strlen(daemonCmd) +1) < 0) {
190 LOGE("Failed to send update command to dnsmasq (%s)", strerror(errno));
191 mDnsForwarders->clear();
192 return -1;
193 }
194 }
195 return 0;
196}
197
198NetAddressCollection *TetherController::getDnsForwarders() {
199 return mDnsForwarders;
200}
201
202int TetherController::tetherInterface(const char *interface) {
203 mInterfaces->push_back(strdup(interface));
204 return 0;
205}
206
207int TetherController::untetherInterface(const char *interface) {
208 InterfaceCollection::iterator it;
209
210 for (it = mInterfaces->begin(); it != mInterfaces->end(); ++it) {
211 if (!strcmp(interface, *it)) {
212 free(*it);
213 mInterfaces->erase(it);
214 return 0;
215 }
216 }
217 errno = ENOENT;
218 return -1;
219}
220
221InterfaceCollection *TetherController::getTetheredInterfaceList() {
222 return mInterfaces;
223}
224