blob: 9337d23184deaffcc3b147a70bf70bb8323b868e [file] [log] [blame]
// Copyright 2015 The Weave Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "examples/provider/wifi_manager.h"
#include <arpa/inet.h>
#include <dirent.h>
#include <linux/wireless.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <fstream>
#include <base/bind.h>
#include <weave/provider/task_runner.h>
#include "examples/provider/event_network.h"
#include "examples/provider/ssl_stream.h"
namespace weave {
namespace examples {
namespace {
int ForkCmd(const std::string& path, const std::vector<std::string>& args) {
int pid = fork();
if (pid != 0)
return pid;
std::vector<const char*> args_vector;
args_vector.push_back(path.c_str());
for (auto& i : args)
args_vector.push_back(i.c_str());
args_vector.push_back(nullptr);
execvp(path.c_str(), const_cast<char**>(args_vector.data()));
NOTREACHED();
return 0;
}
int ForkCmdAndWait(const std::string& path,
const std::vector<std::string>& args) {
int pid = ForkCmd(path, args);
int status = 0;
CHECK_EQ(pid, waitpid(pid, &status, 0));
return status;
}
struct DirCloser {
void operator()(DIR* dir) { closedir(dir); }
};
std::string FindWirelessInterface() {
std::string sysfs_net{"/sys/class/net"};
std::unique_ptr<DIR, DirCloser> net_dir{opendir(sysfs_net.c_str())};
CHECK(net_dir);
dirent* iface;
while ((iface = readdir(net_dir.get()))) {
auto path = sysfs_net + "/" + iface->d_name + "/wireless";
std::unique_ptr<DIR, DirCloser> wireless_dir{opendir(path.c_str())};
if (wireless_dir)
return iface->d_name;
}
return "";
}
} // namespace
WifiImpl::WifiImpl(provider::TaskRunner* task_runner, EventNetworkImpl* network)
: task_runner_{task_runner}, network_{network}, iface_{FindWirelessInterface()} {
CHECK(!iface_.empty()) << "WiFi interface not found";
CHECK_EQ(0u, getuid())
<< "\nWiFi manager expects root access to control WiFi capabilities";
StopAccessPoint();
}
WifiImpl::~WifiImpl() {
StopAccessPoint();
}
void WifiImpl::TryToConnect(const std::string& ssid,
const std::string& passphrase,
int pid,
base::Time until,
const DoneCallback& callback) {
if (pid) {
int status = 0;
if (pid == waitpid(pid, &status, WNOWAIT)) {
int sockf_d = socket(AF_INET, SOCK_DGRAM, 0);
CHECK_GE(sockf_d, 0) << strerror(errno);
iwreq wreq = {};
strncpy(wreq.ifr_name, iface_.c_str(), sizeof(wreq.ifr_name));
std::string essid(' ', IW_ESSID_MAX_SIZE + 1);
wreq.u.essid.pointer = &essid[0];
wreq.u.essid.length = essid.size();
CHECK_GE(ioctl(sockf_d, SIOCGIWESSID, &wreq), 0) << strerror(errno);
essid.resize(wreq.u.essid.length);
close(sockf_d);
if (ssid == essid)
return task_runner_->PostDelayedTask(FROM_HERE,
base::Bind(callback, nullptr), {});
pid = 0; // Try again.
}
}
if (pid == 0) {
pid = ForkCmd("nmcli",
{"dev", "wifi", "connect", ssid, "password", passphrase});
}
if (base::Time::Now() >= until) {
ErrorPtr error;
Error::AddTo(&error, FROM_HERE, "timeout",
"Timeout connecting to WiFI network.");
task_runner_->PostDelayedTask(
FROM_HERE, base::Bind(callback, base::Passed(&error)), {});
return;
}
task_runner_->PostDelayedTask(
FROM_HERE,
base::Bind(&WifiImpl::TryToConnect, weak_ptr_factory_.GetWeakPtr(), ssid,
passphrase, pid, until, callback),
base::TimeDelta::FromSeconds(1));
}
void WifiImpl::Connect(const std::string& ssid,
const std::string& passphrase,
const DoneCallback& callback) {
network_->SetSimulateOffline(false);
CHECK(!hostapd_started_);
if (hostapd_started_) {
ErrorPtr error;
Error::AddTo(&error, FROM_HERE, "busy", "Running Access Point.");
task_runner_->PostDelayedTask(
FROM_HERE, base::Bind(callback, base::Passed(&error)), {});
return;
}
TryToConnect(ssid, passphrase, 0,
base::Time::Now() + base::TimeDelta::FromMinutes(1), callback);
}
void WifiImpl::StartAccessPoint(const std::string& ssid) {
if (hostapd_started_)
return;
// Release wifi interface.
CHECK_EQ(0, ForkCmdAndWait("nmcli", {"nm", "wifi", "off"}));
CHECK_EQ(0, ForkCmdAndWait("rfkill", {"unblock", "wlan"}));
sleep(1);
std::string hostapd_conf = "/tmp/weave_hostapd.conf";
{
std::ofstream ofs(hostapd_conf);
ofs << "interface=" << iface_ << std::endl;
ofs << "channel=1" << std::endl;
ofs << "ssid=" << ssid << std::endl;
}
CHECK_EQ(0, ForkCmdAndWait("hostapd", {"-B", "-K", hostapd_conf}));
hostapd_started_ = true;
for (size_t i = 0; i < 10; ++i) {
if (0 == ForkCmdAndWait("ifconfig", {iface_, "192.168.76.1/24"}))
break;
sleep(1);
}
std::string dnsmasq_conf = "/tmp/weave_dnsmasq.conf";
{
std::ofstream ofs(dnsmasq_conf.c_str());
ofs << "port=0" << std::endl;
ofs << "bind-interfaces" << std::endl;
ofs << "log-dhcp" << std::endl;
ofs << "dhcp-range=192.168.76.10,192.168.76.100" << std::endl;
ofs << "interface=" << iface_ << std::endl;
ofs << "dhcp-leasefile=" << dnsmasq_conf << ".leases" << std::endl;
}
CHECK_EQ(0, ForkCmdAndWait("dnsmasq", {"--conf-file=" + dnsmasq_conf}));
}
void WifiImpl::StopAccessPoint() {
base::IgnoreResult(ForkCmdAndWait("pkill", {"-f", "dnsmasq.*/tmp/weave"}));
base::IgnoreResult(ForkCmdAndWait("pkill", {"-f", "hostapd.*/tmp/weave"}));
CHECK_EQ(0, ForkCmdAndWait("nmcli", {"nm", "wifi", "on"}));
hostapd_started_ = false;
}
bool WifiImpl::HasWifiCapability() {
return !FindWirelessInterface().empty();
}
} // namespace examples
} // namespace weave