775 lines
30 KiB
C++
775 lines
30 KiB
C++
// Copyright (c) 2015-2019 The Bitcoin Core developers
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// Copyright (c) 2017 The Zcash developers
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// Distributed under the MIT software license, see the accompanying
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// file COPYING or http://www.opensource.org/licenses/mit-license.php.
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#include <chainparams.h>
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#include <torcontrol.h>
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#include <util/strencodings.h>
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#include <netbase.h>
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#include <net.h>
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#include <util/system.h>
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#include <crypto/hmac_sha256.h>
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#include <vector>
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#include <deque>
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#include <set>
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#include <stdlib.h>
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#include <boost/signals2/signal.hpp>
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#include <boost/algorithm/string/split.hpp>
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#include <boost/algorithm/string/classification.hpp>
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#include <boost/algorithm/string/replace.hpp>
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#include <event2/bufferevent.h>
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#include <event2/buffer.h>
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#include <event2/util.h>
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#include <event2/event.h>
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#include <event2/thread.h>
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/** Default control port */
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const std::string DEFAULT_TOR_CONTROL = "127.0.0.1:9051";
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/** Tor cookie size (from control-spec.txt) */
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static const int TOR_COOKIE_SIZE = 32;
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/** Size of client/server nonce for SAFECOOKIE */
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static const int TOR_NONCE_SIZE = 32;
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/** For computing serverHash in SAFECOOKIE */
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static const std::string TOR_SAFE_SERVERKEY = "Tor safe cookie authentication server-to-controller hash";
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/** For computing clientHash in SAFECOOKIE */
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static const std::string TOR_SAFE_CLIENTKEY = "Tor safe cookie authentication controller-to-server hash";
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/** Exponential backoff configuration - initial timeout in seconds */
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static const float RECONNECT_TIMEOUT_START = 1.0;
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/** Exponential backoff configuration - growth factor */
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static const float RECONNECT_TIMEOUT_EXP = 1.5;
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/** Maximum length for lines received on TorControlConnection.
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* tor-control-spec.txt mentions that there is explicitly no limit defined to line length,
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* this is belt-and-suspenders sanity limit to prevent memory exhaustion.
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*/
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static const int MAX_LINE_LENGTH = 100000;
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/****** Low-level TorControlConnection ********/
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/** Reply from Tor, can be single or multi-line */
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class TorControlReply
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{
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public:
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TorControlReply() { Clear(); }
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int code;
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std::vector<std::string> lines;
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void Clear()
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{
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code = 0;
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lines.clear();
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}
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};
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/** Low-level handling for Tor control connection.
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* Speaks the SMTP-like protocol as defined in torspec/control-spec.txt
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*/
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class TorControlConnection
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{
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public:
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typedef std::function<void(TorControlConnection&)> ConnectionCB;
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typedef std::function<void(TorControlConnection &,const TorControlReply &)> ReplyHandlerCB;
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/** Create a new TorControlConnection.
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*/
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explicit TorControlConnection(struct event_base *base);
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~TorControlConnection();
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/**
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* Connect to a Tor control port.
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* target is address of the form host:port.
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* connected is the handler that is called when connection is successfully established.
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* disconnected is a handler that is called when the connection is broken.
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* Return true on success.
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*/
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bool Connect(const std::string &target, const ConnectionCB& connected, const ConnectionCB& disconnected);
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/**
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* Disconnect from Tor control port.
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*/
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void Disconnect();
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/** Send a command, register a handler for the reply.
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* A trailing CRLF is automatically added.
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* Return true on success.
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*/
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bool Command(const std::string &cmd, const ReplyHandlerCB& reply_handler);
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/** Response handlers for async replies */
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boost::signals2::signal<void(TorControlConnection &,const TorControlReply &)> async_handler;
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private:
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/** Callback when ready for use */
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std::function<void(TorControlConnection&)> connected;
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/** Callback when connection lost */
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std::function<void(TorControlConnection&)> disconnected;
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/** Libevent event base */
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struct event_base *base;
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/** Connection to control socket */
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struct bufferevent *b_conn;
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/** Message being received */
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TorControlReply message;
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/** Response handlers */
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std::deque<ReplyHandlerCB> reply_handlers;
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/** Libevent handlers: internal */
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static void readcb(struct bufferevent *bev, void *ctx);
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static void eventcb(struct bufferevent *bev, short what, void *ctx);
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};
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TorControlConnection::TorControlConnection(struct event_base *_base):
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base(_base), b_conn(nullptr)
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{
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}
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TorControlConnection::~TorControlConnection()
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{
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if (b_conn)
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bufferevent_free(b_conn);
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}
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void TorControlConnection::readcb(struct bufferevent *bev, void *ctx)
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{
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TorControlConnection *self = static_cast<TorControlConnection*>(ctx);
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struct evbuffer *input = bufferevent_get_input(bev);
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size_t n_read_out = 0;
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char *line;
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assert(input);
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// If there is not a whole line to read, evbuffer_readln returns nullptr
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while((line = evbuffer_readln(input, &n_read_out, EVBUFFER_EOL_CRLF)) != nullptr)
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{
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std::string s(line, n_read_out);
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free(line);
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if (s.size() < 4) // Short line
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continue;
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// <status>(-|+| )<data><CRLF>
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self->message.code = atoi(s.substr(0,3));
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self->message.lines.push_back(s.substr(4));
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char ch = s[3]; // '-','+' or ' '
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if (ch == ' ') {
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// Final line, dispatch reply and clean up
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if (self->message.code >= 600) {
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// Dispatch async notifications to async handler
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// Synchronous and asynchronous messages are never interleaved
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self->async_handler(*self, self->message);
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} else {
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if (!self->reply_handlers.empty()) {
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// Invoke reply handler with message
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self->reply_handlers.front()(*self, self->message);
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self->reply_handlers.pop_front();
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} else {
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LogPrint(BCLog::TOR, "tor: Received unexpected sync reply %i\n", self->message.code);
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}
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}
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self->message.Clear();
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}
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}
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// Check for size of buffer - protect against memory exhaustion with very long lines
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// Do this after evbuffer_readln to make sure all full lines have been
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// removed from the buffer. Everything left is an incomplete line.
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if (evbuffer_get_length(input) > MAX_LINE_LENGTH) {
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LogPrintf("tor: Disconnecting because MAX_LINE_LENGTH exceeded\n");
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self->Disconnect();
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}
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}
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void TorControlConnection::eventcb(struct bufferevent *bev, short what, void *ctx)
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{
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TorControlConnection *self = static_cast<TorControlConnection*>(ctx);
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if (what & BEV_EVENT_CONNECTED) {
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LogPrint(BCLog::TOR, "tor: Successfully connected!\n");
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self->connected(*self);
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} else if (what & (BEV_EVENT_EOF|BEV_EVENT_ERROR)) {
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if (what & BEV_EVENT_ERROR) {
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LogPrint(BCLog::TOR, "tor: Error connecting to Tor control socket\n");
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} else {
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LogPrint(BCLog::TOR, "tor: End of stream\n");
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}
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self->Disconnect();
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self->disconnected(*self);
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}
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}
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bool TorControlConnection::Connect(const std::string &target, const ConnectionCB& _connected, const ConnectionCB& _disconnected)
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{
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if (b_conn)
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Disconnect();
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// Parse target address:port
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struct sockaddr_storage connect_to_addr;
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int connect_to_addrlen = sizeof(connect_to_addr);
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if (evutil_parse_sockaddr_port(target.c_str(),
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(struct sockaddr*)&connect_to_addr, &connect_to_addrlen)<0) {
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LogPrintf("tor: Error parsing socket address %s\n", target);
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return false;
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}
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// Create a new socket, set up callbacks and enable notification bits
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b_conn = bufferevent_socket_new(base, -1, BEV_OPT_CLOSE_ON_FREE);
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if (!b_conn)
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return false;
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bufferevent_setcb(b_conn, TorControlConnection::readcb, nullptr, TorControlConnection::eventcb, this);
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bufferevent_enable(b_conn, EV_READ|EV_WRITE);
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this->connected = _connected;
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this->disconnected = _disconnected;
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// Finally, connect to target
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if (bufferevent_socket_connect(b_conn, (struct sockaddr*)&connect_to_addr, connect_to_addrlen) < 0) {
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LogPrintf("tor: Error connecting to address %s\n", target);
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return false;
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}
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return true;
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}
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void TorControlConnection::Disconnect()
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{
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if (b_conn)
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bufferevent_free(b_conn);
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b_conn = nullptr;
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}
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bool TorControlConnection::Command(const std::string &cmd, const ReplyHandlerCB& reply_handler)
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{
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if (!b_conn)
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return false;
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struct evbuffer *buf = bufferevent_get_output(b_conn);
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if (!buf)
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return false;
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evbuffer_add(buf, cmd.data(), cmd.size());
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evbuffer_add(buf, "\r\n", 2);
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reply_handlers.push_back(reply_handler);
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return true;
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}
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/****** General parsing utilities ********/
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/* Split reply line in the form 'AUTH METHODS=...' into a type
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* 'AUTH' and arguments 'METHODS=...'.
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* Grammar is implicitly defined in https://spec.torproject.org/control-spec by
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* the server reply formats for PROTOCOLINFO (S3.21) and AUTHCHALLENGE (S3.24).
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*/
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std::pair<std::string,std::string> SplitTorReplyLine(const std::string &s)
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{
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size_t ptr=0;
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std::string type;
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while (ptr < s.size() && s[ptr] != ' ') {
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type.push_back(s[ptr]);
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++ptr;
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}
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if (ptr < s.size())
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++ptr; // skip ' '
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return make_pair(type, s.substr(ptr));
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}
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/** Parse reply arguments in the form 'METHODS=COOKIE,SAFECOOKIE COOKIEFILE=".../control_auth_cookie"'.
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* Returns a map of keys to values, or an empty map if there was an error.
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* Grammar is implicitly defined in https://spec.torproject.org/control-spec by
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* the server reply formats for PROTOCOLINFO (S3.21), AUTHCHALLENGE (S3.24),
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* and ADD_ONION (S3.27). See also sections 2.1 and 2.3.
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*/
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std::map<std::string,std::string> ParseTorReplyMapping(const std::string &s)
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{
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std::map<std::string,std::string> mapping;
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size_t ptr=0;
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while (ptr < s.size()) {
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std::string key, value;
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while (ptr < s.size() && s[ptr] != '=' && s[ptr] != ' ') {
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key.push_back(s[ptr]);
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++ptr;
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}
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if (ptr == s.size()) // unexpected end of line
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return std::map<std::string,std::string>();
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if (s[ptr] == ' ') // The remaining string is an OptArguments
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break;
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++ptr; // skip '='
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if (ptr < s.size() && s[ptr] == '"') { // Quoted string
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++ptr; // skip opening '"'
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bool escape_next = false;
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while (ptr < s.size() && (escape_next || s[ptr] != '"')) {
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// Repeated backslashes must be interpreted as pairs
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escape_next = (s[ptr] == '\\' && !escape_next);
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value.push_back(s[ptr]);
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++ptr;
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}
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if (ptr == s.size()) // unexpected end of line
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return std::map<std::string,std::string>();
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++ptr; // skip closing '"'
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/**
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* Unescape value. Per https://spec.torproject.org/control-spec section 2.1.1:
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*
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* For future-proofing, controller implementors MAY use the following
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* rules to be compatible with buggy Tor implementations and with
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* future ones that implement the spec as intended:
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*
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* Read \n \t \r and \0 ... \377 as C escapes.
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* Treat a backslash followed by any other character as that character.
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*/
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std::string escaped_value;
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for (size_t i = 0; i < value.size(); ++i) {
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if (value[i] == '\\') {
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// This will always be valid, because if the QuotedString
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// ended in an odd number of backslashes, then the parser
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// would already have returned above, due to a missing
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// terminating double-quote.
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++i;
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if (value[i] == 'n') {
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escaped_value.push_back('\n');
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} else if (value[i] == 't') {
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escaped_value.push_back('\t');
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} else if (value[i] == 'r') {
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escaped_value.push_back('\r');
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} else if ('0' <= value[i] && value[i] <= '7') {
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size_t j;
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// Octal escape sequences have a limit of three octal digits,
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// but terminate at the first character that is not a valid
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// octal digit if encountered sooner.
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for (j = 1; j < 3 && (i+j) < value.size() && '0' <= value[i+j] && value[i+j] <= '7'; ++j) {}
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// Tor restricts first digit to 0-3 for three-digit octals.
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// A leading digit of 4-7 would therefore be interpreted as
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// a two-digit octal.
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if (j == 3 && value[i] > '3') {
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j--;
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}
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escaped_value.push_back(strtol(value.substr(i, j).c_str(), nullptr, 8));
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// Account for automatic incrementing at loop end
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i += j - 1;
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} else {
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escaped_value.push_back(value[i]);
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}
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} else {
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escaped_value.push_back(value[i]);
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}
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}
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value = escaped_value;
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} else { // Unquoted value. Note that values can contain '=' at will, just no spaces
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while (ptr < s.size() && s[ptr] != ' ') {
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value.push_back(s[ptr]);
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++ptr;
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}
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}
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if (ptr < s.size() && s[ptr] == ' ')
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++ptr; // skip ' ' after key=value
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mapping[key] = value;
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}
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return mapping;
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}
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/** Read full contents of a file and return them in a std::string.
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* Returns a pair <status, string>.
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* If an error occurred, status will be false, otherwise status will be true and the data will be returned in string.
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*
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* @param maxsize Puts a maximum size limit on the file that is read. If the file is larger than this, truncated data
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* (with len > maxsize) will be returned.
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*/
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static std::pair<bool,std::string> ReadBinaryFile(const fs::path &filename, size_t maxsize=std::numeric_limits<size_t>::max())
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{
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FILE *f = fsbridge::fopen(filename, "rb");
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if (f == nullptr)
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return std::make_pair(false,"");
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std::string retval;
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char buffer[128];
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size_t n;
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while ((n=fread(buffer, 1, sizeof(buffer), f)) > 0) {
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// Check for reading errors so we don't return any data if we couldn't
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// read the entire file (or up to maxsize)
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if (ferror(f)) {
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fclose(f);
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return std::make_pair(false,"");
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}
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retval.append(buffer, buffer+n);
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if (retval.size() > maxsize)
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break;
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}
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fclose(f);
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return std::make_pair(true,retval);
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}
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/** Write contents of std::string to a file.
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* @return true on success.
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*/
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static bool WriteBinaryFile(const fs::path &filename, const std::string &data)
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{
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FILE *f = fsbridge::fopen(filename, "wb");
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if (f == nullptr)
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return false;
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if (fwrite(data.data(), 1, data.size(), f) != data.size()) {
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fclose(f);
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return false;
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}
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fclose(f);
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return true;
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}
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/****** Bitcoin specific TorController implementation ********/
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/** Controller that connects to Tor control socket, authenticate, then create
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* and maintain an ephemeral hidden service.
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*/
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class TorController
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{
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public:
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TorController(struct event_base* base, const std::string& target);
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~TorController();
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/** Get name of file to store private key in */
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fs::path GetPrivateKeyFile();
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/** Reconnect, after getting disconnected */
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void Reconnect();
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private:
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struct event_base* base;
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std::string target;
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TorControlConnection conn;
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std::string private_key;
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std::string service_id;
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bool reconnect;
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struct event *reconnect_ev;
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float reconnect_timeout;
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CService service;
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/** Cookie for SAFECOOKIE auth */
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std::vector<uint8_t> cookie;
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/** ClientNonce for SAFECOOKIE auth */
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std::vector<uint8_t> clientNonce;
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/** Callback for ADD_ONION result */
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void add_onion_cb(TorControlConnection& conn, const TorControlReply& reply);
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/** Callback for AUTHENTICATE result */
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void auth_cb(TorControlConnection& conn, const TorControlReply& reply);
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/** Callback for AUTHCHALLENGE result */
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void authchallenge_cb(TorControlConnection& conn, const TorControlReply& reply);
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/** Callback for PROTOCOLINFO result */
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void protocolinfo_cb(TorControlConnection& conn, const TorControlReply& reply);
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/** Callback after successful connection */
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void connected_cb(TorControlConnection& conn);
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/** Callback after connection lost or failed connection attempt */
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void disconnected_cb(TorControlConnection& conn);
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/** Callback for reconnect timer */
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static void reconnect_cb(evutil_socket_t fd, short what, void *arg);
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};
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TorController::TorController(struct event_base* _base, const std::string& _target):
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base(_base),
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target(_target), conn(base), reconnect(true), reconnect_ev(0),
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reconnect_timeout(RECONNECT_TIMEOUT_START)
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{
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reconnect_ev = event_new(base, -1, 0, reconnect_cb, this);
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if (!reconnect_ev)
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LogPrintf("tor: Failed to create event for reconnection: out of memory?\n");
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// Start connection attempts immediately
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if (!conn.Connect(_target, std::bind(&TorController::connected_cb, this, std::placeholders::_1),
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std::bind(&TorController::disconnected_cb, this, std::placeholders::_1) )) {
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LogPrintf("tor: Initiating connection to Tor control port %s failed\n", _target);
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}
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// Read service private key if cached
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std::pair<bool,std::string> pkf = ReadBinaryFile(GetPrivateKeyFile());
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if (pkf.first) {
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LogPrint(BCLog::TOR, "tor: Reading cached private key from %s\n", GetPrivateKeyFile().string());
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private_key = pkf.second;
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}
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}
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TorController::~TorController()
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{
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if (reconnect_ev) {
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event_free(reconnect_ev);
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reconnect_ev = nullptr;
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}
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|
if (service.IsValid()) {
|
|
RemoveLocal(service);
|
|
}
|
|
}
|
|
|
|
void TorController::add_onion_cb(TorControlConnection& _conn, const TorControlReply& reply)
|
|
{
|
|
if (reply.code == 250) {
|
|
LogPrint(BCLog::TOR, "tor: ADD_ONION successful\n");
|
|
for (const std::string &s : reply.lines) {
|
|
std::map<std::string,std::string> m = ParseTorReplyMapping(s);
|
|
std::map<std::string,std::string>::iterator i;
|
|
if ((i = m.find("ServiceID")) != m.end())
|
|
service_id = i->second;
|
|
if ((i = m.find("PrivateKey")) != m.end())
|
|
private_key = i->second;
|
|
}
|
|
if (service_id.empty()) {
|
|
LogPrintf("tor: Error parsing ADD_ONION parameters:\n");
|
|
for (const std::string &s : reply.lines) {
|
|
LogPrintf(" %s\n", SanitizeString(s));
|
|
}
|
|
return;
|
|
}
|
|
service = LookupNumeric(std::string(service_id+".onion"), Params().GetDefaultPort());
|
|
LogPrintf("tor: Got service ID %s, advertising service %s\n", service_id, service.ToString());
|
|
if (WriteBinaryFile(GetPrivateKeyFile(), private_key)) {
|
|
LogPrint(BCLog::TOR, "tor: Cached service private key to %s\n", GetPrivateKeyFile().string());
|
|
} else {
|
|
LogPrintf("tor: Error writing service private key to %s\n", GetPrivateKeyFile().string());
|
|
}
|
|
AddLocal(service, LOCAL_MANUAL);
|
|
// ... onion requested - keep connection open
|
|
} else if (reply.code == 510) { // 510 Unrecognized command
|
|
LogPrintf("tor: Add onion failed with unrecognized command (You probably need to upgrade Tor)\n");
|
|
} else {
|
|
LogPrintf("tor: Add onion failed; error code %d\n", reply.code);
|
|
}
|
|
}
|
|
|
|
void TorController::auth_cb(TorControlConnection& _conn, const TorControlReply& reply)
|
|
{
|
|
if (reply.code == 250) {
|
|
LogPrint(BCLog::TOR, "tor: Authentication successful\n");
|
|
|
|
// 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", "") == "") {
|
|
CService resolved(LookupNumeric("127.0.0.1", 9050));
|
|
proxyType addrOnion = proxyType(resolved, true);
|
|
SetProxy(NET_ONION, addrOnion);
|
|
SetReachable(NET_ONION, true);
|
|
}
|
|
|
|
// Finally - now create the service
|
|
if (private_key.empty()) // No private key, generate one
|
|
private_key = "NEW:RSA1024"; // Explicitly request RSA1024 - see issue #9214
|
|
// Request hidden service, redirect port.
|
|
// Note that the 'virtual' port is always the default port to avoid decloaking nodes using other ports.
|
|
_conn.Command(strprintf("ADD_ONION %s Port=%i,127.0.0.1:%i", private_key, Params().GetDefaultPort(), GetListenPort()),
|
|
std::bind(&TorController::add_onion_cb, this, std::placeholders::_1, std::placeholders::_2));
|
|
} else {
|
|
LogPrintf("tor: Authentication failed\n");
|
|
}
|
|
}
|
|
|
|
/** Compute Tor SAFECOOKIE response.
|
|
*
|
|
* ServerHash is computed as:
|
|
* HMAC-SHA256("Tor safe cookie authentication server-to-controller hash",
|
|
* CookieString | ClientNonce | ServerNonce)
|
|
* (with the HMAC key as its first argument)
|
|
*
|
|
* After a controller sends a successful AUTHCHALLENGE command, the
|
|
* next command sent on the connection must be an AUTHENTICATE command,
|
|
* and the only authentication string which that AUTHENTICATE command
|
|
* will accept is:
|
|
*
|
|
* HMAC-SHA256("Tor safe cookie authentication controller-to-server hash",
|
|
* CookieString | ClientNonce | ServerNonce)
|
|
*
|
|
*/
|
|
static std::vector<uint8_t> ComputeResponse(const std::string &key, const std::vector<uint8_t> &cookie, const std::vector<uint8_t> &clientNonce, const std::vector<uint8_t> &serverNonce)
|
|
{
|
|
CHMAC_SHA256 computeHash((const uint8_t*)key.data(), key.size());
|
|
std::vector<uint8_t> computedHash(CHMAC_SHA256::OUTPUT_SIZE, 0);
|
|
computeHash.Write(cookie.data(), cookie.size());
|
|
computeHash.Write(clientNonce.data(), clientNonce.size());
|
|
computeHash.Write(serverNonce.data(), serverNonce.size());
|
|
computeHash.Finalize(computedHash.data());
|
|
return computedHash;
|
|
}
|
|
|
|
void TorController::authchallenge_cb(TorControlConnection& _conn, const TorControlReply& reply)
|
|
{
|
|
if (reply.code == 250) {
|
|
LogPrint(BCLog::TOR, "tor: SAFECOOKIE authentication challenge successful\n");
|
|
std::pair<std::string,std::string> l = SplitTorReplyLine(reply.lines[0]);
|
|
if (l.first == "AUTHCHALLENGE") {
|
|
std::map<std::string,std::string> m = ParseTorReplyMapping(l.second);
|
|
if (m.empty()) {
|
|
LogPrintf("tor: Error parsing AUTHCHALLENGE parameters: %s\n", SanitizeString(l.second));
|
|
return;
|
|
}
|
|
std::vector<uint8_t> serverHash = ParseHex(m["SERVERHASH"]);
|
|
std::vector<uint8_t> serverNonce = ParseHex(m["SERVERNONCE"]);
|
|
LogPrint(BCLog::TOR, "tor: AUTHCHALLENGE ServerHash %s ServerNonce %s\n", HexStr(serverHash), HexStr(serverNonce));
|
|
if (serverNonce.size() != 32) {
|
|
LogPrintf("tor: ServerNonce is not 32 bytes, as required by spec\n");
|
|
return;
|
|
}
|
|
|
|
std::vector<uint8_t> computedServerHash = ComputeResponse(TOR_SAFE_SERVERKEY, cookie, clientNonce, serverNonce);
|
|
if (computedServerHash != serverHash) {
|
|
LogPrintf("tor: ServerHash %s does not match expected ServerHash %s\n", HexStr(serverHash), HexStr(computedServerHash));
|
|
return;
|
|
}
|
|
|
|
std::vector<uint8_t> computedClientHash = ComputeResponse(TOR_SAFE_CLIENTKEY, cookie, clientNonce, serverNonce);
|
|
_conn.Command("AUTHENTICATE " + HexStr(computedClientHash), std::bind(&TorController::auth_cb, this, std::placeholders::_1, std::placeholders::_2));
|
|
} else {
|
|
LogPrintf("tor: Invalid reply to AUTHCHALLENGE\n");
|
|
}
|
|
} else {
|
|
LogPrintf("tor: SAFECOOKIE authentication challenge failed\n");
|
|
}
|
|
}
|
|
|
|
void TorController::protocolinfo_cb(TorControlConnection& _conn, const TorControlReply& reply)
|
|
{
|
|
if (reply.code == 250) {
|
|
std::set<std::string> methods;
|
|
std::string cookiefile;
|
|
/*
|
|
* 250-AUTH METHODS=COOKIE,SAFECOOKIE COOKIEFILE="/home/x/.tor/control_auth_cookie"
|
|
* 250-AUTH METHODS=NULL
|
|
* 250-AUTH METHODS=HASHEDPASSWORD
|
|
*/
|
|
for (const std::string &s : reply.lines) {
|
|
std::pair<std::string,std::string> l = SplitTorReplyLine(s);
|
|
if (l.first == "AUTH") {
|
|
std::map<std::string,std::string> m = ParseTorReplyMapping(l.second);
|
|
std::map<std::string,std::string>::iterator i;
|
|
if ((i = m.find("METHODS")) != m.end())
|
|
boost::split(methods, i->second, boost::is_any_of(","));
|
|
if ((i = m.find("COOKIEFILE")) != m.end())
|
|
cookiefile = i->second;
|
|
} else if (l.first == "VERSION") {
|
|
std::map<std::string,std::string> m = ParseTorReplyMapping(l.second);
|
|
std::map<std::string,std::string>::iterator i;
|
|
if ((i = m.find("Tor")) != m.end()) {
|
|
LogPrint(BCLog::TOR, "tor: Connected to Tor version %s\n", i->second);
|
|
}
|
|
}
|
|
}
|
|
for (const std::string &s : methods) {
|
|
LogPrint(BCLog::TOR, "tor: Supported authentication method: %s\n", s);
|
|
}
|
|
// Prefer NULL, otherwise SAFECOOKIE. If a password is provided, use HASHEDPASSWORD
|
|
/* Authentication:
|
|
* cookie: hex-encoded ~/.tor/control_auth_cookie
|
|
* password: "password"
|
|
*/
|
|
std::string torpassword = gArgs.GetArg("-torpassword", "");
|
|
if (!torpassword.empty()) {
|
|
if (methods.count("HASHEDPASSWORD")) {
|
|
LogPrint(BCLog::TOR, "tor: Using HASHEDPASSWORD authentication\n");
|
|
boost::replace_all(torpassword, "\"", "\\\"");
|
|
_conn.Command("AUTHENTICATE \"" + torpassword + "\"", std::bind(&TorController::auth_cb, this, std::placeholders::_1, std::placeholders::_2));
|
|
} else {
|
|
LogPrintf("tor: Password provided with -torpassword, but HASHEDPASSWORD authentication is not available\n");
|
|
}
|
|
} else if (methods.count("NULL")) {
|
|
LogPrint(BCLog::TOR, "tor: Using NULL authentication\n");
|
|
_conn.Command("AUTHENTICATE", std::bind(&TorController::auth_cb, this, std::placeholders::_1, std::placeholders::_2));
|
|
} else if (methods.count("SAFECOOKIE")) {
|
|
// Cookie: hexdump -e '32/1 "%02x""\n"' ~/.tor/control_auth_cookie
|
|
LogPrint(BCLog::TOR, "tor: Using SAFECOOKIE authentication, reading cookie authentication from %s\n", cookiefile);
|
|
std::pair<bool,std::string> status_cookie = ReadBinaryFile(cookiefile, TOR_COOKIE_SIZE);
|
|
if (status_cookie.first && status_cookie.second.size() == TOR_COOKIE_SIZE) {
|
|
// _conn.Command("AUTHENTICATE " + HexStr(status_cookie.second), std::bind(&TorController::auth_cb, this, std::placeholders::_1, std::placeholders::_2));
|
|
cookie = std::vector<uint8_t>(status_cookie.second.begin(), status_cookie.second.end());
|
|
clientNonce = std::vector<uint8_t>(TOR_NONCE_SIZE, 0);
|
|
GetRandBytes(clientNonce.data(), TOR_NONCE_SIZE);
|
|
_conn.Command("AUTHCHALLENGE SAFECOOKIE " + HexStr(clientNonce), std::bind(&TorController::authchallenge_cb, this, std::placeholders::_1, std::placeholders::_2));
|
|
} else {
|
|
if (status_cookie.first) {
|
|
LogPrintf("tor: Authentication cookie %s is not exactly %i bytes, as is required by the spec\n", cookiefile, TOR_COOKIE_SIZE);
|
|
} else {
|
|
LogPrintf("tor: Authentication cookie %s could not be opened (check permissions)\n", cookiefile);
|
|
}
|
|
}
|
|
} else if (methods.count("HASHEDPASSWORD")) {
|
|
LogPrintf("tor: The only supported authentication mechanism left is password, but no password provided with -torpassword\n");
|
|
} else {
|
|
LogPrintf("tor: No supported authentication method\n");
|
|
}
|
|
} else {
|
|
LogPrintf("tor: Requesting protocol info failed\n");
|
|
}
|
|
}
|
|
|
|
void TorController::connected_cb(TorControlConnection& _conn)
|
|
{
|
|
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");
|
|
}
|
|
|
|
void TorController::disconnected_cb(TorControlConnection& _conn)
|
|
{
|
|
// Stop advertising service when disconnected
|
|
if (service.IsValid())
|
|
RemoveLocal(service);
|
|
service = CService();
|
|
if (!reconnect)
|
|
return;
|
|
|
|
LogPrint(BCLog::TOR, "tor: Not connected to Tor control port %s, trying to reconnect\n", target);
|
|
|
|
// Single-shot timer for reconnect. Use exponential backoff.
|
|
struct timeval time = MillisToTimeval(int64_t(reconnect_timeout * 1000.0));
|
|
if (reconnect_ev)
|
|
event_add(reconnect_ev, &time);
|
|
reconnect_timeout *= RECONNECT_TIMEOUT_EXP;
|
|
}
|
|
|
|
void TorController::Reconnect()
|
|
{
|
|
/* Try to reconnect and reestablish if we get booted - for example, Tor
|
|
* may be restarting.
|
|
*/
|
|
if (!conn.Connect(target, 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", target);
|
|
}
|
|
}
|
|
|
|
fs::path TorController::GetPrivateKeyFile()
|
|
{
|
|
return GetDataDir() / "onion_private_key";
|
|
}
|
|
|
|
void TorController::reconnect_cb(evutil_socket_t fd, short what, void *arg)
|
|
{
|
|
TorController *self = static_cast<TorController*>(arg);
|
|
self->Reconnect();
|
|
}
|
|
|
|
/****** Thread ********/
|
|
static struct event_base *gBase;
|
|
static std::thread torControlThread;
|
|
|
|
static void TorControlThread()
|
|
{
|
|
TorController ctrl(gBase, gArgs.GetArg("-torcontrol", DEFAULT_TOR_CONTROL));
|
|
|
|
event_base_dispatch(gBase);
|
|
}
|
|
|
|
void StartTorControl()
|
|
{
|
|
assert(!gBase);
|
|
#ifdef WIN32
|
|
evthread_use_windows_threads();
|
|
#else
|
|
evthread_use_pthreads();
|
|
#endif
|
|
gBase = event_base_new();
|
|
if (!gBase) {
|
|
LogPrintf("tor: Unable to create event_base\n");
|
|
return;
|
|
}
|
|
|
|
torControlThread = std::thread(std::bind(&TraceThread<void (*)()>, "torcontrol", &TorControlThread));
|
|
}
|
|
|
|
void InterruptTorControl()
|
|
{
|
|
if (gBase) {
|
|
LogPrintf("tor: Thread interrupt\n");
|
|
event_base_once(gBase, -1, EV_TIMEOUT, [](evutil_socket_t, short, void*) {
|
|
event_base_loopbreak(gBase);
|
|
}, nullptr, nullptr);
|
|
}
|
|
}
|
|
|
|
void StopTorControl()
|
|
{
|
|
if (gBase) {
|
|
torControlThread.join();
|
|
event_base_free(gBase);
|
|
gBase = nullptr;
|
|
}
|
|
}
|