torcontrol: Launch a private Tor instance when not already running

This commit is contained in:
Luke Dashjr 2019-02-15 20:15:43 +00:00
parent 47e5e7678b
commit aa6834d0a0
3 changed files with 175 additions and 12 deletions

View File

@ -512,6 +512,11 @@ void SetupServerArgs(ArgsManager& argsman)
argsman.AddArg("-timeout=<n>", strprintf("Specify socket connection timeout in milliseconds. If an initial attempt to connect is unsuccessful after this amount of time, drop it (minimum: 1, default: %d)", DEFAULT_CONNECT_TIMEOUT), ArgsManager::ALLOW_ANY, OptionsCategory::CONNECTION);
argsman.AddArg("-peertimeout=<n>", strprintf("Specify a p2p connection timeout delay in seconds. After connecting to a peer, wait this amount of time before considering disconnection based on inactivity (minimum: 1, default: %d)", DEFAULT_PEER_CONNECT_TIMEOUT), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CONNECTION);
argsman.AddArg("-torcontrol=<ip>:<port>", strprintf("Tor control host and port to use if onion listening enabled (default: %s). If no port is specified, the default port of %i will be used.", DEFAULT_TOR_CONTROL, DEFAULT_TOR_CONTROL_PORT), ArgsManager::ALLOW_ANY, OptionsCategory::CONNECTION);
#ifdef HAVE_BOOST_PROCESS
argsman.AddArg("-torexecute=<command>", strprintf("Tor command to use if not already running (default: %s)", DEFAULT_TOR_EXECUTE), ArgsManager::ALLOW_ANY, OptionsCategory::CONNECTION);
#else
hidden_args.emplace_back("-torexecute=<command>");
#endif
argsman.AddArg("-torpassword=<pass>", "Tor control port password (default: empty)", ArgsManager::ALLOW_ANY | ArgsManager::SENSITIVE, OptionsCategory::CONNECTION);
#ifdef USE_UPNP
#if USE_UPNP

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@ -26,8 +26,10 @@
#include <algorithm>
#include <cassert>
#include <chrono>
#include <cstdlib>
#include <deque>
#include <fstream>
#include <functional>
#include <map>
#include <optional>
@ -36,6 +38,27 @@
#include <utility>
#include <vector>
#ifdef HAVE_BOOST_PROCESS
// Boost 1.77 requires the following workaround.
// See: https://github.com/boostorg/process/issues/213
#include <algorithm>
#if defined(WIN32) && !defined(__kernel_entry)
// Boost 1.71-1.77 requires the following workaround for compatibility with mingw-w64 compiler.
// See: https://github.com/bitcoin/bitcoin/pull/22348
#define __kernel_entry
#endif
#if defined(__GNUC__)
// Boost 1.78 requires the following workaround.
// See: https://github.com/boostorg/process/issues/235
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wnarrowing"
#endif
#include <boost/process.hpp>
#if defined(__GNUC__)
#pragma GCC diagnostic pop
#endif
#endif
#include <event2/buffer.h>
#include <event2/bufferevent.h>
#include <event2/event.h>
@ -44,6 +67,7 @@
/** Default control ip and port */
const std::string DEFAULT_TOR_CONTROL = "127.0.0.1:" + ToString(DEFAULT_TOR_CONTROL_PORT);
const std::string DEFAULT_TOR_EXECUTE = "tor";
/** Tor cookie size (from control-spec.txt) */
static const int TOR_COOKIE_SIZE = 32;
/** Size of client/server nonce for SAFECOOKIE */
@ -76,6 +100,10 @@ TorControlConnection::~TorControlConnection()
bufferevent_free(b_conn);
}
void TorControlConnection::IgnoreReplyHandler(TorControlConnection &a, const TorControlReply &b)
{
}
void TorControlConnection::readcb(struct bufferevent *bev, void *ctx)
{
TorControlConnection *self = static_cast<TorControlConnection*>(ctx);
@ -314,18 +342,20 @@ std::map<std::string,std::string> ParseTorReplyMapping(const std::string &s)
return mapping;
}
TorController::TorController(struct event_base* _base, const std::string& tor_control_center, const CService& target):
TorController::TorController(struct event_base* _base, const std::string& tor_control_center, const CService& target, const std::string& execute):
base(_base),
m_tor_control_center(tor_control_center), conn(base), reconnect(true), reconnect_timeout(RECONNECT_TIMEOUT_START),
m_connect_tor_control_center(tor_control_center), conn(base), reconnect(true), reconnect_timeout(RECONNECT_TIMEOUT_START),
m_execute(execute),
m_target(target)
{
reconnect_ev = event_new(base, -1, 0, reconnect_cb, this);
if (!reconnect_ev)
LogPrintf("tor: Failed to create event for reconnection: out of memory?\n");
// Start connection attempts immediately
if (!conn.Connect(m_tor_control_center, std::bind(&TorController::connected_cb, this, std::placeholders::_1),
m_current_tor_control_center = tor_control_center;
if (!conn.Connect(m_current_tor_control_center, std::bind(&TorController::connected_cb, this, std::placeholders::_1),
std::bind(&TorController::disconnected_cb, this, std::placeholders::_1) )) {
LogPrintf("tor: Initiating connection to Tor control port %s failed\n", m_tor_control_center);
LogPrintf("tor: Initiating connection to Tor control port %s failed\n", m_current_tor_control_center);
}
// Read service private key if cached
std::pair<bool,std::string> pkf = ReadBinaryFile(GetPrivateKeyFile());
@ -344,6 +374,12 @@ TorController::~TorController()
if (service.IsValid()) {
RemoveLocal(service);
}
#ifdef HAVE_BOOST_PROCESS
if (m_process) {
conn.Command("SIGNAL SHUTDOWN");
delete m_process;
}
#endif
}
void TorController::get_socks_cb(TorControlConnection& _conn, const TorControlReply& reply)
@ -453,9 +489,20 @@ void TorController::auth_cb(TorControlConnection& _conn, const TorControlReply&
if (reply.code == 250) {
LogPrint(BCLog::TOR, "Authentication successful\n");
#ifdef HAVE_BOOST_PROCESS
if (m_process) {
_conn.Command("TAKEOWNERSHIP");
}
#endif
// Now that we know Tor is running setup the proxy for onion addresses
// if -onion isn't set to something else.
if (gArgs.GetArg("-onion", "") == "") {
// NOTE: Our own private Tor doesn't do SOCKS, so don't configure it
if (gArgs.GetArg("-onion", "") == ""
#ifdef HAVE_BOOST_PROCESS
&& !m_process
#endif
) {
_conn.Command("GETINFO net/listeners/socks", std::bind(&TorController::get_socks_cb, this, std::placeholders::_1, std::placeholders::_2));
}
@ -612,22 +659,91 @@ void TorController::protocolinfo_cb(TorControlConnection& _conn, const TorContro
void TorController::connected_cb(TorControlConnection& _conn)
{
m_try_exec = false;
reconnect_timeout = RECONNECT_TIMEOUT_START;
// First send a PROTOCOLINFO command to figure out what authentication is expected
if (!_conn.Command("PROTOCOLINFO 1", std::bind(&TorController::protocolinfo_cb, this, std::placeholders::_1, std::placeholders::_2)))
LogPrintf("tor: Error sending initial protocolinfo command\n");
}
std::string TorController::LaunchTor()
{
#ifdef HAVE_BOOST_PROCESS
fs::path tor_datadir = gArgs.GetDataDirNet() / "tor";
const fs::path controlport_env_filepath = tor_datadir / "controlport.env";
fs::remove(controlport_env_filepath); // may throw exceptions
if (m_process) {
m_process->terminate();
delete m_process;
m_process = nullptr;
}
boost::process::opstream in;
try {
m_process = new boost::process::child(m_execute + " -f -", boost::process::std_in < in);
} catch (...) {
LogPrint(BCLog::TOR, "tor: Failed to execute Tor process\n");
throw;
}
in << "SOCKSPort 0" << std::endl;
in << "DataDirectory " << fs::PathToString(tor_datadir) << std::endl;
in << "ControlPort auto" << std::endl;
in << "ControlPortWriteToFile " << fs::PathToString(controlport_env_filepath) << std::endl;
in << "CookieAuthentication 1" << std::endl;
in.pipe().close();
while (!fs::exists(controlport_env_filepath)) {
if (!m_process->running()) {
LogPrint(BCLog::TOR, "tor: Tor process died before making control port file\n");
throw std::runtime_error("tor process died");
}
std::this_thread::sleep_for(std::chrono::seconds(1));
}
std::ifstream controlport_file(controlport_env_filepath);
std::string portline;
controlport_file >> portline;
if (portline.compare(0, 5, "PORT=")) {
LogPrint(BCLog::TOR, "tor: Unrecognized control port line in file\n");
m_process->terminate();
delete m_process;
m_process = nullptr;
throw std::runtime_error("port line unrecognized");
}
return portline.substr(5);
#else
throw std::runtime_error("not supported");
#endif
}
void TorController::disconnected_cb(TorControlConnection& _conn)
{
// Stop advertising service when disconnected
if (service.IsValid())
RemoveLocal(service);
service = CService();
#ifdef HAVE_BOOST_PROCESS
if (m_try_exec && !m_execute.empty()) {
LogPrint(BCLog::TOR, "tor: Not connected to Tor control port %s, trying to launch via %s\n", m_current_tor_control_center, m_execute);
try {
m_current_tor_control_center = LaunchTor();
Reconnect();
return;
} catch (...) {
// fall through to normal reconnect logic
}
}
#endif
if (!reconnect)
return;
LogPrint(BCLog::TOR, "Not connected to Tor control port %s, trying to reconnect\n", m_tor_control_center);
LogPrint(BCLog::TOR, "Not connected to Tor control port %s, trying to reconnect in %s seconds\n", m_current_tor_control_center, reconnect_timeout);
m_current_tor_control_center = m_connect_tor_control_center;
m_try_exec = true; // if this fails
// Single-shot timer for reconnect. Use exponential backoff.
struct timeval time = MillisToTimeval(int64_t(reconnect_timeout * 1000.0));
@ -641,9 +757,9 @@ void TorController::Reconnect()
/* Try to reconnect and reestablish if we get booted - for example, Tor
* may be restarting.
*/
if (!conn.Connect(m_tor_control_center, std::bind(&TorController::connected_cb, this, std::placeholders::_1),
if (!conn.Connect(m_current_tor_control_center, std::bind(&TorController::connected_cb, this, std::placeholders::_1),
std::bind(&TorController::disconnected_cb, this, std::placeholders::_1) )) {
LogPrintf("tor: Re-initiating connection to Tor control port %s failed\n", m_tor_control_center);
LogPrintf("tor: Re-initiating connection to Tor control port %s failed\n", m_current_tor_control_center);
}
}
@ -664,7 +780,17 @@ static std::thread torControlThread;
static void TorControlThread(CService onion_service_target)
{
TorController ctrl(gBase, gArgs.GetArg("-torcontrol", DEFAULT_TOR_CONTROL), onion_service_target);
#ifdef HAVE_BOOST_PROCESS
std::string execute_command = gArgs.GetArg("-torexecute", DEFAULT_TOR_EXECUTE);
if (execute_command == "1") {
execute_command = DEFAULT_TOR_EXECUTE;
} else if (execute_command == "0") {
execute_command.clear();
}
#else
const std::string execute_command;
#endif
TorController ctrl(gBase, gArgs.GetArg("-torcontrol", DEFAULT_TOR_CONTROL), onion_service_target, execute_command);
event_base_dispatch(gBase);
}

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@ -8,9 +8,31 @@
#ifndef BITCOIN_TORCONTROL_H
#define BITCOIN_TORCONTROL_H
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <netaddress.h>
#include <util/fs.h>
#ifdef HAVE_BOOST_PROCESS
#if defined(WIN32) && !defined(__kernel_entry)
// A workaround for boost 1.71 incompatibility with mingw-w64 compiler.
// For details see https://github.com/bitcoin/bitcoin/pull/22348.
#define __kernel_entry
#endif
#if defined(__GNUC__)
// Boost 1.78 requires the following workaround.
// See: https://github.com/boostorg/process/issues/235
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wnarrowing"
#endif
#include <boost/process.hpp>
#if defined(__GNUC__)
#pragma GCC diagnostic pop
#endif
#endif
#include <event2/util.h>
#include <cstdint>
@ -21,6 +43,7 @@
constexpr int DEFAULT_TOR_CONTROL_PORT = 9051;
extern const std::string DEFAULT_TOR_CONTROL;
extern const std::string DEFAULT_TOR_EXECUTE;
static const bool DEFAULT_LISTEN_ONION = true;
void StartTorControl(CService onion_service_target);
@ -53,6 +76,7 @@ class TorControlConnection
public:
typedef std::function<void(TorControlConnection&)> ConnectionCB;
typedef std::function<void(TorControlConnection &,const TorControlReply &)> ReplyHandlerCB;
static void IgnoreReplyHandler(TorControlConnection &, const TorControlReply &);
/** Create a new TorControlConnection.
*/
@ -77,7 +101,7 @@ public:
* A trailing CRLF is automatically added.
* Return true on success.
*/
bool Command(const std::string &cmd, const ReplyHandlerCB& reply_handler);
bool Command(const std::string &cmd, const ReplyHandlerCB& reply_handler = IgnoreReplyHandler);
private:
/** Callback when ready for use */
@ -106,7 +130,7 @@ private:
class TorController
{
public:
TorController(struct event_base* base, const std::string& tor_control_center, const CService& target);
TorController(struct event_base* base, const std::string& tor_control_center, const CService& target, const std::string& execute);
TorController() : conn{nullptr} {
// Used for testing only.
}
@ -119,13 +143,19 @@ public:
void Reconnect();
private:
struct event_base* base;
const std::string m_tor_control_center;
const std::string m_connect_tor_control_center;
std::string m_current_tor_control_center;
TorControlConnection conn;
std::string private_key;
std::string service_id;
bool m_try_exec{true};
bool reconnect;
struct event *reconnect_ev = nullptr;
float reconnect_timeout;
std::string m_execute{DEFAULT_TOR_EXECUTE};
#ifdef HAVE_BOOST_PROCESS
boost::process::child *m_process{nullptr};
#endif
CService service;
const CService m_target;
/** Cookie for SAFECOOKIE auth */
@ -151,6 +181,8 @@ public:
/** Callback for reconnect timer */
static void reconnect_cb(evutil_socket_t fd, short what, void *arg);
std::string LaunchTor();
};
#endif // BITCOIN_TORCONTROL_H