torcontrol improvements and fixes

- Force AUTHCOOKIE size to be 32 bytes: This provides protection against
  an attack where a process pretends to be Tor and uses the cookie
  authentication method to nab arbitrary files such as the
  wallet
- torcontrol logging
- fix cookie auth
- add HASHEDPASSWORD auth, fix fd leak when fwrite() fails
- better error reporting when cookie file is not ok
- better init/shutdown flow
- stop advertizing service when disconnected from tor control port
- COOKIE->SAFECOOKIE auth

src/init.cpp

@@ -160,6 +160,7 @@ void Interrupt(boost::thread_group& threadGroup)
     InterruptHTTPRPC();
     InterruptRPC();
     InterruptREST();
+    InterruptTorControl();
     threadGroup.interrupt_all();
 }
 
@@ -362,6 +363,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-seednode=<ip>", _("Connect to a node to retrieve peer addresses, and disconnect"));
     strUsage += HelpMessageOpt("-timeout=<n>", strprintf(_("Specify connection timeout in milliseconds (minimum: 1, default: %d)"), DEFAULT_CONNECT_TIMEOUT));
     strUsage += HelpMessageOpt("-torcontrol=<ip>:<port>", strprintf(_("Tor control port to use if onion listening enabled (default: %s)"), DEFAULT_TOR_CONTROL));
+    strUsage += HelpMessageOpt("-torpassword=<pass>", _("Tor control port password (default: empty)"));
 #ifdef USE_UPNP
 #if USE_UPNP
     strUsage += HelpMessageOpt("-upnp", _("Use UPnP to map the listening port (default: 1 when listening and no -proxy)"));