src/command_parse.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2014, 2018-2020 Sadie Powell <sadie@witchery.services>
   5  *   Copyright (C) 2012-2016, 2018 Attila Molnar <attilamolnar@hush.com>
   6  *   Copyright (C) 2012 Robby <robby@chatbelgie.be>
   7  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   8  *   Copyright (C) 2007-2009 Robin Burchell <robin+git@viroteck.net>
   9  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
  10  *   Copyright (C) 2005-2008, 2010 Craig Edwards <brain@inspircd.org>
  11  *
  12  * This file is part of InspIRCd.  InspIRCd is free software: you can
  13  * redistribute it and/or modify it under the terms of the GNU General Public
  14  * License as published by the Free Software Foundation, version 2.
  15  *
  16  * This program is distributed in the hope that it will be useful, but WITHOUT
  17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25
  26 #include "inspircd.h"
  27
  28 bool InspIRCd::PassCompare(Extensible* ex, const std::string& data, const std::string& input, const std::string& hashtype)
  29 {
  30         ModResult res;
  31         FIRST_MOD_RESULT(OnPassCompare, res, (ex, data, input, hashtype));
  32
  33         /* Module matched */
  34         if (res == MOD_RES_ALLOW)
  35                 return true;
  36
  37         /* Module explicitly didnt match */
  38         if (res == MOD_RES_DENY)
  39                 return false;
  40
  41         /* We dont handle any hash types except for plaintext - Thanks tra26 */
  42         if (!hashtype.empty() && !stdalgo::string::equalsci(hashtype, "plaintext"))
  43                 return false;
  44
  45         return TimingSafeCompare(data, input);
  46 }
  47
  48 bool CommandParser::LoopCall(User* user, Command* handler, const CommandBase::Params& parameters, unsigned int splithere, int extra, bool usemax)
  49 {
  50         if (splithere >= parameters.size())
  51                 return false;
  52
  53         /* First check if we have more than one item in the list, if we don't we return false here and the handler
  54          * which called us just carries on as it was.
  55          */
  56         if (parameters[splithere].find(',') == std::string::npos)
  57                 return false;
  58
  59         /** Some lame ircds will weed out dupes using some shitty O(n^2) algorithm.
  60          * By using std::set (thanks for the idea w00t) we can cut this down a ton.
  61          * ...VOOODOOOO!
  62          *
  63          * Only check for duplicates if there is one list (allow them in JOIN).
  64          */
  65         insp::flat_set<std::string, irc::insensitive_swo> dupes;
  66         bool check_dupes = (extra < 0);
  67
  68         /* Create two sepstreams, if we have only one list, then initialize the second sepstream with
  69          * an empty string. The second parameter of the constructor of the sepstream tells whether
  70          * or not to allow empty tokens.
  71          * We allow empty keys, so "JOIN #a,#b ,bkey" will be interpreted as "JOIN #a", "JOIN #b bkey"
  72          */
  73         irc::commasepstream items1(parameters[splithere]);
  74         irc::commasepstream items2(extra >= 0 ? parameters[extra] : "", true);
  75         std::string item;
  76         unsigned int max = 0;
  77         LocalUser* localuser = IS_LOCAL(user);
  78
  79         /* Attempt to iterate these lists and call the command handler
  80          * for every parameter or parameter pair until there are no more
  81          * left to parse.
  82          */
  83         CommandBase::Params splitparams(parameters);
  84         while (items1.GetToken(item) && (!usemax || max++ < ServerInstance->Config->MaxTargets))
  85         {
  86                 if ((!check_dupes) || (dupes.insert(item).second))
  87                 {
  88                         splitparams[splithere] = item;
  89
  90                         if (extra >= 0)
  91                         {
  92                                 // If we have two lists then get the next item from the second list.
  93                                 // In case it runs out of elements then 'item' will be an empty string.
  94                                 items2.GetToken(item);
  95                                 splitparams[extra] = item;
  96                         }
  97
  98                         CmdResult result = handler->Handle(user, splitparams);
  99                         if (localuser)
 100                         {
 101                                 // Run the OnPostCommand hook with the last parameter being true to indicate
 102                                 // that the event is being called in a loop.
 103                                 item.clear();
 104                                 FOREACH_MOD(OnPostCommand, (handler, splitparams, localuser, result, true));
 105                         }
 106                 }
 107         }
 108
 109         return true;
 110 }
 111
 112 Command* CommandParser::GetHandler(const std::string &commandname)
 113 {
 114         CommandMap::iterator n = cmdlist.find(commandname);
 115         if (n != cmdlist.end())
 116                 return n->second;
 117
 118         return NULL;
 119 }
 120
 121 // calls a handler function for a command
 122
 123 CmdResult CommandParser::CallHandler(const std::string& commandname, const CommandBase::Params& parameters, User* user, Command** cmd)
 124 {
 125         CommandMap::iterator n = cmdlist.find(commandname);
 126
 127         if (n != cmdlist.end())
 128         {
 129                 if ((!parameters.empty()) && (parameters.back().empty()) && (!n->second->allow_empty_last_param))
 130                         return CMD_INVALID;
 131
 132                 if (parameters.size() >= n->second->min_params)
 133                 {
 134                         bool bOkay = false;
 135
 136                         if (IS_LOCAL(user) && n->second->flags_needed)
 137                         {
 138                                 /* if user is local, and flags are needed .. */
 139
 140                                 if (user->IsModeSet(n->second->flags_needed))
 141                                 {
 142                                         /* if user has the flags, and now has the permissions, go ahead */
 143                                         if (user->HasCommandPermission(commandname))
 144                                                 bOkay = true;
 145                                 }
 146                         }
 147                         else
 148                         {
 149                                 /* remote or no flags required anyway */
 150                                 bOkay = true;
 151                         }
 152
 153                         if (bOkay)
 154                         {
 155                                 if (cmd)
 156                                         *cmd = n->second;
 157
 158                                 ClientProtocol::TagMap tags;
 159                                 return n->second->Handle(user, CommandBase::Params(parameters, tags));
 160                         }
 161                 }
 162         }
 163         return CMD_INVALID;
 164 }
 165
 166 void CommandParser::ProcessCommand(LocalUser* user, std::string& command, CommandBase::Params& command_p)
 167 {
 168         /* find the command, check it exists */
 169         Command* handler = GetHandler(command);
 170
 171         // Penalty to give if the command fails before the handler is executed
 172         unsigned int failpenalty = 0;
 173
 174         /* Modify the user's penalty regardless of whether or not the command exists */
 175         if (!user->HasPrivPermission("users/flood/no-throttle"))
 176         {
 177                 // If it *doesn't* exist, give it a slightly heftier penalty than normal to deter flooding us crap
 178                 unsigned int penalty = (handler ? handler->Penalty * 1000 : 2000);
 179                 user->CommandFloodPenalty += penalty;
 180
 181                 // Increase their penalty later if we fail and the command has 0 penalty by default (i.e. in Command::Penalty) to
 182                 // throttle sending ERR_* from the command parser. If the command does have a non-zero penalty then this is not
 183                 // needed because we've increased their penalty above.
 184                 if (penalty == 0)
 185                         failpenalty = 1000;
 186         }
 187
 188         if (!handler)
 189         {
 190                 ModResult MOD_RESULT;
 191                 FIRST_MOD_RESULT(OnPreCommand, MOD_RESULT, (command, command_p, user, false));
 192                 if (MOD_RESULT == MOD_RES_DENY)
 193                 {
 194                         FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 195                         return;
 196                 }
 197
 198                 /*
 199                  * This double lookup is in case a module (abbreviation) wishes to change a command.
 200                  * Sure, the double lookup is a bit painful, but bear in mind this only happens for unknowns anyway.
 201                  *
 202                  * Thanks dz for making me actually understand why this is necessary!
 203                  * -- w00t
 204                  */
 205                 handler = GetHandler(command);
 206                 if (!handler)
 207                 {
 208                         if (user->registered == REG_ALL)
 209                                 user->WriteNumeric(ERR_UNKNOWNCOMMAND, command, "Unknown command");
 210
 211                         ServerInstance->stats.Unknown++;
 212                         FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 213                         return;
 214                 }
 215         }
 216
 217         // If we were given more parameters than max_params then append the excess parameter(s)
 218         // to command_p[maxparams-1], i.e. to the last param that is still allowed
 219         if (handler->max_params && command_p.size() > handler->max_params)
 220         {
 221                 /*
 222                  * command_p input (assuming max_params 1):
 223                  *      this
 224                  *      is
 225                  *      a
 226                  *      test
 227                  */
 228
 229                 // Iterator to the last parameter that will be kept
 230                 const CommandBase::Params::iterator lastkeep = command_p.begin() + (handler->max_params - 1);
 231                 // Iterator to the first excess parameter
 232                 const CommandBase::Params::iterator firstexcess = lastkeep + 1;
 233
 234                 // Append all excess parameter(s) to the last parameter, separated by spaces
 235                 for (CommandBase::Params::const_iterator i = firstexcess; i != command_p.end(); ++i)
 236                 {
 237                         lastkeep->push_back(' ');
 238                         lastkeep->append(*i);
 239                 }
 240
 241                 // Erase the excess parameter(s)
 242                 command_p.erase(firstexcess, command_p.end());
 243         }
 244
 245         /*
 246          * We call OnPreCommand here separately if the command exists, so the magic above can
 247          * truncate to max_params if necessary. -- w00t
 248          */
 249         ModResult MOD_RESULT;
 250         FIRST_MOD_RESULT(OnPreCommand, MOD_RESULT, (command, command_p, user, false));
 251         if (MOD_RESULT == MOD_RES_DENY)
 252         {
 253                 FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 254                 return;
 255         }
 256
 257         /* activity resets the ping pending timer */
 258         user->nextping = ServerInstance->Time() + user->MyClass->GetPingTime();
 259
 260         if (handler->flags_needed)
 261         {
 262                 if (!user->IsModeSet(handler->flags_needed))
 263                 {
 264                         user->CommandFloodPenalty += failpenalty;
 265                         user->WriteNumeric(ERR_NOPRIVILEGES, "Permission Denied - You do not have the required operator privileges");
 266                         FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 267                         return;
 268                 }
 269
 270                 if (!user->HasCommandPermission(command))
 271                 {
 272                         user->CommandFloodPenalty += failpenalty;
 273                         user->WriteNumeric(ERR_NOPRIVILEGES, InspIRCd::Format("Permission Denied - Oper type %s does not have access to command %s",
 274                                 user->oper->name.c_str(), command.c_str()));
 275                         FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 276                         return;
 277                 }
 278         }
 279
 280         if ((!command_p.empty()) && (command_p.back().empty()) && (!handler->allow_empty_last_param))
 281                 command_p.pop_back();
 282
 283         if (command_p.size() < handler->min_params)
 284         {
 285                 user->CommandFloodPenalty += failpenalty;
 286                 handler->TellNotEnoughParameters(user, command_p);
 287                 FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 288                 return;
 289         }
 290
 291         if ((user->registered != REG_ALL) && (!handler->works_before_reg))
 292         {
 293                 user->CommandFloodPenalty += failpenalty;
 294                 handler->TellNotRegistered(user, command_p);
 295                 FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 296         }
 297         else
 298         {
 299                 /* passed all checks.. first, do the (ugly) stats counters. */
 300                 handler->use_count++;
 301
 302                 /* module calls too */
 303                 FIRST_MOD_RESULT(OnPreCommand, MOD_RESULT, (command, command_p, user, true));
 304                 if (MOD_RESULT == MOD_RES_DENY)
 305                 {
 306                         FOREACH_MOD(OnCommandBlocked, (command, command_p, user));
 307                         return;
 308                 }
 309
 310                 /*
 311                  * WARNING: be careful, the user may be deleted soon
 312                  */
 313                 CmdResult result = handler->Handle(user, command_p);
 314
 315                 FOREACH_MOD(OnPostCommand, (handler, command_p, user, result, false));
 316         }
 317 }
 318
 319 void CommandParser::RemoveCommand(Command* x)
 320 {
 321         CommandMap::iterator n = cmdlist.find(x->name);
 322         if (n != cmdlist.end() && n->second == x)
 323                 cmdlist.erase(n);
 324 }
 325
 326 void CommandParser::ProcessBuffer(LocalUser* user, const std::string& buffer)
 327 {
 328         ClientProtocol::ParseOutput parseoutput;
 329         if (!user->serializer->Parse(user, buffer, parseoutput))
 330                 return;
 331
 332         std::string& command = parseoutput.cmd;
 333         std::transform(command.begin(), command.end(), command.begin(), ::toupper);
 334
 335         CommandBase::Params parameters(parseoutput.params, parseoutput.tags);
 336         ProcessCommand(user, command, parameters);
 337 }
 338
 339 bool CommandParser::AddCommand(Command *f)
 340 {
 341         /* create the command and push it onto the table */
 342         if (cmdlist.find(f->name) == cmdlist.end())
 343         {
 344                 cmdlist[f->name] = f;
 345                 return true;
 346         }
 347         return false;
 348 }
 349
 350 CommandParser::CommandParser()
 351 {
 352 }
 353
 354 std::string CommandParser::TranslateUIDs(const std::vector<TranslateType>& to, const CommandBase::Params& source, bool prefix_final, CommandBase* custom_translator)
 355 {
 356         std::vector<TranslateType>::const_iterator types = to.begin();
 357         std::string dest;
 358
 359         for (unsigned int i = 0; i < source.size(); i++)
 360         {
 361                 TranslateType t = TR_TEXT;
 362                 // They might supply less translation types than parameters,
 363                 // in that case pretend that all remaining types are TR_TEXT
 364                 if (types != to.end())
 365                 {
 366                         t = *types;
 367                         types++;
 368                 }
 369
 370                 bool last = (i == (source.size() - 1));
 371                 if (prefix_final && last)
 372                         dest.push_back(':');
 373
 374                 TranslateSingleParam(t, source[i], dest, custom_translator, i);
 375
 376                 if (!last)
 377                         dest.push_back(' ');
 378         }
 379
 380         return dest;
 381 }
 382
 383 void CommandParser::TranslateSingleParam(TranslateType to, const std::string& item, std::string& dest, CommandBase* custom_translator, unsigned int paramnumber)
 384 {
 385         switch (to)
 386         {
 387                 case TR_NICK:
 388                 {
 389                         /* Translate single nickname */
 390                         User* user = ServerInstance->FindNick(item);
 391                         if (user)
 392                                 dest.append(user->uuid);
 393                         else
 394                                 dest.append(item);
 395                         break;
 396                 }
 397                 case TR_CUSTOM:
 398                 {
 399                         if (custom_translator)
 400                         {
 401                                 std::string translated = item;
 402                                 custom_translator->EncodeParameter(translated, paramnumber);
 403                                 dest.append(translated);
 404                                 break;
 405                         }
 406                         // If no custom translator was given, fall through
 407                 }
 408                 /*@fallthrough@*/
 409                 default:
 410                         /* Do nothing */
 411                         dest.append(item);
 412                 break;
 413         }
 414 }